EP2844937A1

EP2844937A1 - System having a process chamber for workpieces

Info

Publication number: EP2844937A1
Application number: EP13720886.4A
Authority: EP
Inventors: Dietmar Wieland; Oliver Iglauer; Christof KNÜSEL; Marius Winkler
Original assignee: Duerr Systems AG
Current assignee: Duerr Systems AG
Priority date: 2012-05-02
Filing date: 2013-04-26
Publication date: 2015-03-11
Anticipated expiration: 2033-04-26
Also published as: EP2844937B1; PT3336467T; US9423179B2; US20150121720A1; EP3336467A1; BR112014024884B1; CN104583699B; DE102012207312A1; WO2013164285A1; EP2844937B2; CN104583699A; IN2014DN07532A; TR201820376T4; PL3336467T3; ES2705601T3; EP3336467B1

Abstract

The invention relates to a system (1), comprising a process chamber (5), which comprises an interior (39) having an accommodating region (15) for workpieces (3). The process chamber (5) has an opening (12, 14) for supplying or removing workpieces (3). The process chamber (5) is formed with a device (17, 9, 25, 29, 33, 37, 35) for blowing gaseous fluid into the interior (39), which device has at least one nozzle (17, 19) or orifice for producing a fluid flow curtain (21, 23) between the opening (12, 14) and the accommodating region (15) for workpieces (3). The process chamber (5) has an apparatus (74) for supplying fresh air, by means of which fresh air can be introduced into the accommodating region (15) on a side of the fluid flow curtain (21, 23) facing away from the opening (12, 14).

Description

The invention relates to a system with a process chamber, which has an interior space with a workpiece receiving area and with an opening for the supply or removal of workpieces, and with a device for injecting gaseous fluid into the process chamber Interior comprising at least one nozzle or orifice for creating a fluid flow curtain between the opening and the workpiece receiving area.

Such a system is known from WO 2010/122121 A1.

In car body varnishing and coating shops, drying systems are used for drying freshly painted or corrosion-protected vehicle bodies. These systems have a process chamber designed as a dryer tunnel, into which hot air is blown. There is a drying zone in the dryer tunnel. The drying zone is a receiving area for workpieces in the form of vehicle bodies. To dry the vehicle bodies, they are moved on a conveyor through the dryer tunnel. The lacquer layer or coating of the vehicle bodies to be dried can be adversely affected by impurities, in particular dust particles. Furthermore, gaseous fluid and heat can escape from the interior through an opening for feeding workpieces.

The object of the invention is to provide a system with a process chamber which has an interior space with a receiving area for workpieces, which can be at least partially opened, in which simple means an efficient thermal separation of this interior from the environment is possible and at at the same time a sufficient fresh air supply for the receiving area can be ensured. This object is achieved by a plant of the type mentioned above, which has a device for supplying fresh air into the process can, with the on a side facing away from the opening of the fluid flow curtain into the receiving area fresh air can be introduced.

The term fresh air is understood to mean, in particular, pre-compressed, heated and / or mechanically and / or mechanically cleaned and / or dried air with a filter whose state parameters are set as required. Fresh air can z. B. also be processed exhaust air from a process chamber. In addition, fresh air can also be the exhaust gas from a heat engine or internal combustion engine. By supplying fresh air into the receiving area of the process chamber, it is possible to ensure that the solvent content of the air inside the process chamber does not exceed threshold values when drying workpieces above which drying processes are impaired and above which combustible solvents of paints, varnishes, adhesives and / or coatings can cause explosions because an explosion limit is exceeded.

The invention is based on the idea that at least one airlock of a process chamber in a drying plant fulfills a double task: fresh air supplied in the airlocks, which generates a fresh air curtain, can on the one hand serve to separate the interior fluidically and / or thermally from the environment. On the other hand, it can be achieved with the fresh air of the fresh air curtain that the solvent released during drying processes in the process chamber is sufficiently diluted by feeding this fresh air into the process chamber. Since the first task is load-independent and the second load-dependent, the inventors propose to separate this double task of the airlocks. It should be a guided in the process chamber volume flow can be reduced or increased in fluid according to the utilization of the process can. In particular, fresh air and / or recirculated exhaust air come into consideration as fluids. If a fresh air stream supplied to the process chamber of a drying plant is heated to a dryer temperature, adapting the fresh air volume flow to the load allows a temporary lowering of the fresh air volume flow below its maximum value and thus a lowering of the energy consumption.

The device for supplying fresh air in the system preferably contains at least one line communicating with the receiving area, which has an opening for the intake of fresh air and which has a flow control device. The flow control device may, for. B. include a throttle and / or an adjustable blower. The system may in particular comprise a device for circulating gaseous fluid in the receiving area through a recirculating air line system communicating with the receiving area, which is guided out of the receiving area by a device for tempering, in particular for heating gaseous fluid. The process chamber supplied fresh air can be z. B. before or behind a heat exchanger in the device for tempering in the recirculation system can be fed. However, it is also possible to feed the fresh air into a line section of the recirculating air line system, through which circulating air from the process chamber is passed to the temperature control device or through the circulating air, which is conditioned in the temperature control device, into the process chamber.

The system may also include means for supplying fresh air into the receiving area, which has at least one conduit with an opening for the intake of fresh air, which is connected to the circulating air duct system. In this case, a circulating air blower can be used at low cost alternately or at the same time for the promotion of fresh air. In The flow control system is optionally provided with a flow control device, wherein the flow control device is advantageously arranged in a flow channel or a return channel of the recirculation system. In the recirculating air duct system, a heat exchanger and / or a heater are further optionally provided, wherein the heat exchanger preferably transfers heat from an exhaust gas stream into a fresh air stream within the device for supplying fresh air into the receiving area and wherein a heating device preferably z. B. is connected to a solar thermal system and / or with a gas burner.

The line with the opening for the intake of fresh air can in particular lead into a flow channel or return channel within the circulating air duct system. The plant may also include means for supplying fresh air into the receiving area, which has at least one conduit with an opening for the intake of fresh air, which is connected directly to the process chamber. The flow control device is preferably part of a (higher-level) control or regulating circuit, which supplies the receiving area with conditioned fluid, in particular with fresh air and possibly recirculated, treated exhaust air. The flow control device can be directly or indirectly connected to a control or regulating circuit which contains a device for detecting a state parameter of the process chamber and controls or regulates the amount of introduced into the receiving area fresh air by means of the flow control device.

The process chamber in the plant may include means for monitoring an operation of the process chamber designed to detect a condition parameter from the group indicated below: i. Carbon content and / or solvent content of the atmosphere in the receiving area;

ii. Number and / or weight and / or type and / or size of the surface of workpieces arranged in the receiving area;

iii. Number and / or weight and / or type and / or size of the surface of the receiving area per unit time supplied workpieces;

iv. Temperature of the exhaust air of a burner in a device for tempering circulating air;

v. Temperature difference of gaseous fluid taken from the receiving area and returned to the receiving area;

vi. Temperature difference of gaseous fluid from the receiving region, which is supplied to a combustion chamber of a burner in a device for tempering circulating air, and of exhaust air from the combustion chamber of the burner;

vii. Amount of heat per unit time, which is supplied to the process chamber. The process chamber in the plant can also be designed with a receiving area, which is subdivided into a first receiving area and a further receiving area, wherein the device for injecting gaseous fluid into the interior creates a fluid flow curtain between the first receiving area and the further receiving area.

The apparatus for injecting gaseous fluid into the interior of the process chamber includes at least one nozzle or at least one orifice for creating a fluid flow curtain between the opening and the workpiece receiving area. The at least one nozzle or at least one aperture preferably serves as an outlet opening for air heated above ambient temperature and / or compressed over ambient pressure (or a correspondingly processed inert gas such as CO ₂ or N ₂ ). The process chamber can, for. B. contain gaseous fluid whose temperature T is above 100 ° C and / or for which a temperature difference to the environment of the process chamber is more than 50 ° C. In one exemplary embodiment, fluid is flowed in approximately perpendicularly from top to bottom into the process chamber. In a further preferred embodiment, the fluid flowing in through the nozzle has a temperature which is higher or lower by more than 20 ° C. than the (approximately stationary) fluid contained in the process chamber. In the following, reference will be made primarily to a rigid or adjustable nozzle geometry, wherein the invention can also be implemented with one or more simple diaphragms.

The interior of the process chamber is preferably designed tunnel-shaped. He has a floor and a ceiling. Since the at least one nozzle is designed as a slot nozzle with a substantially rectangular outlet cross-section, the gaseous fluid can be supplied via the ceiling of the interior with a flow direction oblique with respect to the bottom, such that they face toward the bottom or the inlet opening - The side of the fluid flow curtain forms a flow roll of air, which is at least partially mixed with injected fluid.

One idea of the invention is, in particular, that the fluid flow curtain can be produced with a reduced expenditure of energy when the gaseous fluid injected into the interior via the at least one nozzle is guided on a guide contour which projects into the interior space. It is particularly advantageous if this guide contour can be pivoted. This makes it possible to adjust the fluid flow curtain with respect to the horizontal. Preferably, an angle between 80 ° and 50 ° is set between outflow direction and horizontal. When this angle is set between the outflow direction and the horizontal, the fluid flow curtain generates a flow roll on its lower side, which is in the direction of flow, which faces towards the bottom or to an opening. The fluid flow of the fluid flow curtain pushes against the gaseous fluid that is in the region of the bottom of the process chamber. The fluid flow of the fluid flow curtain overlaps and mixes with fluid exiting the process chamber in the region of the bottom. In particular, can be achieved by the pivoting of the lead contour that workpieces are not affected when entering the process chamber or at the exit.

It is particularly advantageous if a wall is arranged on the side facing the opening of the guide contour, which defines a diffuser with the guide contour, which contains a mixing chamber. With respect to the mean flow direction of the gaseous fluid from the at least one nozzle, the diffuser is designed asymmetrically. The mixing chamber in the diffuser is located on the upstream side of the fluid flow from the nozzle facing downwardly. The mixing chamber is positioned in the diffuser such that fluid is mixed with air from the region of the opening on a side of the fluid flow curtain facing the opening (i.e., outwardly of the interior of the process chamber). The air is sucked here by the flowing through the nozzle or the aperture, gaseous fluid into the roll.

The wall may have one or more openings for the passage of circulated air from the region of the opening.

By forming an auxiliary chamber acting as a "dead space" for gaseous fluid on a side of the guide contour facing away from the mixing chamber, it is possible to ensure that the flow of gaseous fluid emerging from the nozzle or orifice along the guide contour without a flow demolition is performed. In the "dead space", preference is given to lower flow velocities than outside the dead space.The arrangement of an additional guide vane in the mixing chamber makes it possible to bring large amounts of fluid out of the flow roll into the fluid flow curtain.

By an end wall is arranged on the side facing the input opening of the guide vane, which defines a retaining space with the guide contour, circulated air from the region of the inlet opening, which is directed in the region of the guide vane in an edge region of the interior, before escaping into the open be withheld.

The end wall conveniently has one or more openings for the passage of circulated air from the area of the inlet opening. The at least one nozzle may include means for adjusting the flow rate of fluid passing through the nozzle. By providing a plurality of nozzles with means for adjusting the flow rate of fluid passing through the nozzle, the fluid flow curtain between the input aperture and the workpiece receiving area can be set differently in different sections.

The device for injecting gaseous fluid may include a heater for heating the gaseous fluid. This makes it possible to ensure that in the region of openings of the process chamber no condensate, z. B. condensation occurs. The process chamber is suitable for use in a drying and / or curing plant. In particular, the process chamber can be integrated into a paint shop. In the process chamber, the fluid flow curtain is created with gaseous fluid which is pressurized and passed through a nozzle. In this case, in the adjacent to the nozzle mixing chamber air from the region of an opening of the process chamber admixed with the gaseous fluid flowing out of the nozzle. The guided through the nozzle gaseous fluid is guided along a boundary defining the mixing chamber along. This guide contour separates the mixing chamber from an auxiliary chamber, which acts as a dead space for gaseous fluid, arranged adjacently thereto.

In particular, the process chamber may be operated to throttle or interrupt a stream of gaseous fluid passed through a nozzle for creating a fluid flow curtain between the opening and the workpiece receiving area and / or changing the direction of the fluid flow curtain when a workpiece is moved through the opening. This ensures that the fluid flow curtain does not damage the surface of the coating of workpieces being moved in and out of the process chamber.

In the following the invention will be explained in more detail with reference to the embodiments schematically illustrated in the drawing. Show it:

1 shows a first drying system for vehicle bodies.

2 shows a longitudinal section of a lock of the drying plant.

3 shows a three-dimensional view of the lock;

4 shows the flow conditions for air in the region of the lock; a longitudinal section of another lock for a drying plant; 6 and Fig. 7 and Fig. 8 sections further longitudinal sections of alternative embodiments for locks in a drying plant;

9 shows a cross section of a dryer tunnel in a drying plant;

10 shows a longitudinal section of another lock;

Fig. 1 1 a second drying system for vehicle bodies; and

FIGS. 12 to 19 further alternative arrangements for drying workpieces.

The plant 1 shown in Fig. 1 for drying z. B. metallic workpieces is designed especially for vehicle body 3. The plant 1 comprises a drying chamber 5 designed as a process chamber. Through the drying tunnel 5, the vehicle bodies 3, which are mounted on skids 7, can be moved by means of a conveying device 9. The conveyor has an electric drive 10. The dryer tunnel 5 is lined with sheet metal. It has an entrance lock 1 1 with an inlet opening 12 and an exit lock 13 with an outlet opening 14. The dryer tunnel 5 comprises a drying zone 15 which lies between the entrance lock 1 1 and the exit lock 13. The drying zone 15 is a receiving area for workpieces. The drying zone 15 is preferably designed such that about fifteen vehicle bodies 3 freshly coated with a paint and / or a solvent can be dried more or less simultaneously. For this purpose, the drying section 15 z. B. with the length L = 40 m, a clear width b with 1, 40 m <b <2.70 m and a clear height h with 2.00 m <h <2.60 m designed. In a particularly preferred embodiment results in a pitch of 5.2 m, thirty units per hour and 0.5 hr. Dwell a tunnel length of 78 m (width b outside: 3 m to 4.6 m, height h outside: 2.8 m to 3.3 m). By means of a device 70 for the provision of conditioned gaseous fluid is fed into the drying section 15 fluid for drying. The device 70 preferably contains a circulating-air line system 72 communicating with the drying zone 15. The circulating-air line system 72 communicates with the receiving area 15 and has a feed channel 75 acting as a recirculating suck-back channel and contains a return channel 77 which serves as a recirculation return channel for the recirculation of the circulated air. The Umluftleitungssys- system 72 is guided by a heater 63. In the device 70 there is a fan 61, with which the air is blown to dry. With the device 70, the air in the drying zone 15 can be maintained in a circulating air operating condition at a defined temperature. The system 1 further preferably contains a device 74 and, alternatively or additionally, a device 74 'for the supply of fluid in the form of optionally also conditioned fresh air. The device 74, 74 'has a conduit 76, 76' with an opening 78, 78 'for the intake of fresh air. In the line 76, 76 'there is a flow control device 80, 80', which is designed as a throttle valve. The line 76, 76 'is advantageously connected to the recirculation system 72.

In order to remove solvent evaporating from the fluid atmosphere in the dryer tunnel 5 from paint, adhesives or coatings of the vehicle bodies 3, there is a line 65 or even several lines for exhaust air in the system 1, via the air loaded with solvent from the dryer tunnel 5 to a cleaning reactor 67 can be supplied.

In the entrance lock 1 1 and the exit lock 13 of the dryer tunnel 5 there is in each case a nozzle 17, 19 for generating a fluid flow curtain 21, 23. The nozzles 17, 19 are operated via a compressor for fresh air 25, 27 through a ceiling 6 of the drying nertunnels 5 arranged chamber 29, 31 supplied with fresh air. The nozzles 17, 19 preferably have a narrow slot-shaped opening 33, 35, which extends substantially over the width of the dryer tunnel 5 or over the width of the inlet or outlet openings 12, 14. The slot-shaped opening 33, 35 of the nozzles 17, 19 opens into the interior 39 of the dryer tunnel 5. The fluid flowing out of the nozzles 17, 19 is guided via a diffuser 16, 18 into the interior of the dryer tunnel 5. The diffuser 16, 18 extends in front of the nozzles 17, 19 across the width of the inlet or outlet opening 12, 14. The diffuser 16, 18 is designed asymmetrically with respect to the direction of the fluid flow curtain 21, 23 and is characterized by a baffle with a Leitkontur 21 1 and an end wall 215 limited. The fluid flowing out of the nozzles 17, 19 is guided at the guide contour 21 1 of the guide plate into the interior of the dryer tunnel. For an advantageously possible detection of the temperature T of the fluid 39 supplied to the interior 39 via the nozzles 17, 19, a temperature sensor 69, 71 is located on the guide contour 21 1.

The fluid flow curtain 21, 23 preferably extends at an angle of 50 ° <α <80 ° with respect to the horizontal 37. It is directed into the inner space 39 of the dryer tunnel 5. The fluid flow flowing out of the nozzles 17, 19 widens up to the bottom 41 of the dryer tunnel 5. With increasing distance from the opening 33, 35 of the nozzles 17, 19, the velocity of the flow of the fluid flow curtain 21, 23 forming fresh air decreases as gaseous fluid. The fluid flow curtain 21, 23 separates the gas atmosphere in the interior 39 of the dryer tunnel 5 from the ambient air 42. By means of a control device 45, 47, the fluid flow emerging from the nozzles 17, 19 is set to a predetermined shape. For detecting the concentration of solvent in the gas atmosphere of the dryer tunnel 5, a solvent sensor 73 is arranged in the drying zone 15. Alternatively or additionally, such a solvent sensor in be arranged the exhaust duct 65. The gaseous fluid supplied to the nozzles 17, 19 in the form of air is preheated in a heating device 43, 44 to a desired process temperature T _so n, which is preferably in a temperature range of 160 ° C. <T _so n -S 250 ° C. By the fluid flow curtain 21, 23 consists of fresh air, it can be ensured that a lower explosion limit for organic solvents in the drying zone 15 of the dryer tunnel 5 is not exceeded. The preheating of the supplied fluid causes in the entrance lock 1 1 and the exit lock 13 of the dryer tunnel 5 no condensate is formed.

In order to ensure that the explosion limit is maintained in the drying zone 15, fresh air can be introduced via the device 74 or 74 'into the drying section 15 if necessary. For adjusting the amount of fresh air supplied via the device 74 or 74 'into the dryer tunnel 5, the control device 45 is connected to the flow control device 80. With the control device 45 via the line 76 and 76 'supplied fresh air is set to a predetermined value. The adjustment of the fresh air supply takes place as a function of the detected by means of a sensor 49, 51 as Prozesskammer- operating state parameter number per unit time by the drying zone 15 of the dryer tunnel 5 moving vehicle bodies and / or due to the signals of the temperature sensors 69, 71 and / or the solvent sensor 73rd and / or one or more other process chamber operating state parameters that allow statements about the composition of the gas atmosphere in the dryer tunnel 5 and thus the determination of the fresh air requirement when operating the dryer tunnel 5. The fresh air supply is adjusted so that when operating the system 1, the so-called lower explosion limit of the composition of the gas atmosphere in the dryer tunnel 5 is not exceeded. In order to detect process chamber operating state parameters, in a modified embodiment of the system 1, as an alternative to the sensor 49, a light barrier may also be provided for determining the number of vehicle bodies moved through the dryer tunnel 5 per unit of time. Alternatively or in addition to the sensor 49, it is also possible to equip the system with a measuring device with which the weight of the vehicle bodies 3 supplied to the dryer tunnel 5 can be determined and / or a device with which the size of the surface coating provided surface of the vehicle bodies 3 can be detected. In addition, the system 1 can also be equipped with a device for detecting a workpieces, z. B. the vehicle body 3 or even on a Skid 7 attached digital codes, eg. B. a bar code, the digital information about the size and nature of a workpiece, z. B. on a vehicle body 3 applied surface coating or on a particular type of workpiece contains.

In a system according to the invention, the determination of the fresh air requirement of the process chamber, in particular of a dryer tunnel for motor vehicle bodies, can be based on a predefined type of workpiece z. B. be carried out as follows:

About a mass detection device and a piece number detection device, the mass and number of existing in the process chamber or located on the way into the process chamber workpieces is determined. For each measured value of the mass of a workpiece taking into account expected fluctuations, which comes into consideration due to the treated in the plant workpieces, a workpiece type is stored in the control device 45 thereby. From the determined in the controller 45 type of workpiece can be in the controller 45 then close to the size of the painted surface of this workpiece. From the relevant value for the size of the surface can then a fresh air requirement of the Prozesskannnner be set on the discharged from this surface amount of solvent, which is necessary for z. B. the proportion of combustible solvent in the gas atmosphere of the process chamber 15 remains below the explosion limit.

According to the invention, in particular, the mass of a workpiece determined with the mass detection device is then applied to a specific workpiece, ie. H. closed a certain workpiece type. For the specific workpiece is then applied to this paint or coating amount, and then assumed from this assumed paint or coating amount to a in the applied to the workpiece paint or the coating disposed thereon solvent amount. In combination with the number of pieces in the process chamber in question, a total amount of solvent can then be determined, which is introduced into the process chamber during the drying of workpieces. From this, the fresh air requirement for the process chamber can then be determined in order to operate it below the explosion limit.

It should be noted that a device for detecting the mass and quantity of workpieces according to the invention z. B. may be formed as a weighing device with which the number of weighing operations is detected. In order to take into account the thermal inertia of the overall system, it is advantageous to provide a device for detecting a workpiece parameter in front of the process chamber. In the remaining time to the entrance of a workpiece in the process chamber can then z. B. on the amount of introduced into the process chamber fresh air in the process chamber, a desired process temperature and / or a desired composition of the gas atmosphere can be adjusted. It should also be noted that the thermal inertia of a plant described above is essentially determined by the heat capacity of the process chamber and the size of the air supplied to these and discharged from this.

By connecting the above-mentioned devices to the control device 45, it is possible to control the composition of the gas atmosphere by adjusting the fresh air supply according to the requirements of the vehicle bodies 3 arranged in the dryer tunnel 5, taking into account, in particular, the solvent content in the surface coating of the vehicle bodies 3 to regulate.

The system 1 can thus z. B. operated in the following operating conditions:

Operating state 1:

With the fluid flow curtain 21, 23 in the input and output locks 1 1, 13 a constant fresh air volume flow is supplied, which ensures not only a sufficient seal of the interior 39, but also a sufficient dilution of a Losemittelgehalts in the atmosphere of the drying zone 15th The dryer tunnel 5 is loaded here independently of capacity with the volume flow that is required for the supplied at full capacity solvent. Operating state 2:

With the fluid flow curtain 21, 23, a constant fresh air volume flow is supplied to the inlet and outlet locks 1 1, 13, which ensures a sufficient sealing of the interior 39. In order to ensure a sufficient dilution of the solvent content in the atmosphere of the drying zone 15, additional fresh air is supplied by the device 74. The amount of fresh air supplied with the device 74 is adjusted by the controller 45 and changes with the Utilization of the plant 1. If the drying zone 15 more fresh air is supplied, must be removed from the dryer tunnel 5 at the same time a corresponding amount of exhaust air via the line 65 so that the system 1 is in equilibrium and in the dryer tunnel 5 no excess or negative pressures.

FIG. 2 is a sectional view of the entrance lock 1 1 of the drying installation 1 from FIG. 1. The nozzle 17 in the entrance lock 1 1 is a slot nozzle. The nozzle 17 is supplied with the fresh air heated in the heating device 44 via a pipeline 201. The pipeline 201 opens into a chamber 203. In the chamber 203, the fresh air is passed via air filter 205 and an obliquely arranged housing plate 206 to the nozzle 17. In the lock 1 1 there is a baffle 207. The baffle 207 is fixedly connected to the housing plate 206. The baffle 207 and the housing plate 206 can be pivoted in the lock 1 1 about an axis of rotation 208 in the direction of the arrow 214. The pivoting of the baffle 207 with the housing plate 206 opens access to the filter 205 so that maintenance work can be performed there. The nozzle 17 has a slot-shaped opening 209. The slot-shaped opening 209 of the nozzle 17 is set back in relation to the ceiling 6 of the dryer tunnel 5. This makes it possible to avoid impairments and damage to a not yet dried coating of vehicle bodies, which are moved through the entry lock 11 into the dryer tunnel 5, even at high flow speeds of a fluid flow leaving the nozzle 17. Important for the avoidance of such damage is a comparatively large distance of the opening 209 of the nozzle 17 from the bottom 41 of the dryer tunnel 5. This can be achieved by a recessed arrangement of the nozzle 17 in the drying tunnel 5. This ensures that the momentum of the gaseous fluid flowing out of the nozzle 17 is weakened so far already in the middle of the dryer tunnel that corresponding coatings of vehicle bodies 3 by the fluid flow curtain 21 can not be damaged. The fluid flow 210 emerging from the opening 209 of the nozzle 17 is guided into the interior of the dryer tunnel 5 along the contour 21 1 of a guide plate 207 acting as a guide wing. The length L of the contour 21 1 of the baffle 207 preferably corresponds to 20 to 40 times the slot width B of the nozzle opening 209th

There is an end wall 215 on the side of the contour 21 1 facing the inlet opening 213 of the dryer tunnel 5. The end wall 215 extends over the width of the lock 11. The end wall 215 delimits the diffuser 16 with the contour 21 1, a ridge element 212 and the contour 21 1 of the baffle 207. The diffuser 16 is made asymmetrical with respect to the main flow plane 202 of the fluid flowing out of the nozzle 17. The main flow plane 202 and the contour of the baffle 21 1 are at an angle φ to each other. The portion of the diffuser 16 located on the side facing the end wall 215 of the plane 204 symmetrical with respect to the contour of the baffle 21 1 with respect to the main flow plane 202 and including the angle 2φ with the contour of the baffle 21 1 acts as one Mixing chamber 217 for gaseous fluid 219. The mixing chamber 217 is placed back relative to the cover 6 of the dryer tunnel 5. The diffuser 16 with the mixing chamber 217 is located in the lock 1 1 above the inlet opening 213. The mixing chamber 217 is adjacent to the inlet opening 213. The baffle with the contour 21 1 separates the mixing chamber 217 from a secondary chamber 216. The secondary chamber 216 opens into the interior 39 of the dryer tunnel 5. The secondary chamber 216 forms a dead space for air from the dryer tunnel 5. The on the back of the baffle With the guide contour 21 1 formed secondary chamber causes the fluid flow 210 is guided on the Leitkontur 21 1 due to the Coanda effect without stall.

Fig. 3 is a three-dimensional view of the entrance lock 1 1 of Fig. 2. The slot-shaped opening 209 of the nozzle 17 extends over the The slot-shaped opening 209 of the nozzle 17 is so narrow that the fluid flow emerging from the nozzle 17 forms a fluid flow curtain over a wide flow range with different outlet speeds. This fluid flow in particular prevents entry of dirt particles 301 from the surroundings of the drying installation 1 shown in FIG. 1 into the interior of the dryer tunnel 5.

4 shows with arrows the flow conditions for air in the entrance lock 1 1 in the plane of a longitudinal section of the dryer tunnel 5 from FIG. 1. The drying air supplied to the dryer tunnel 5 via the slot-shaped nozzle 17 causes a fluid flow curtain 401 on the outlet side of the nozzle 17. Starting from the opening 209 of the nozzle 17, the fluid flow curtain 401 extends from fresh air flowing in the direction of the arrows 402 in the form of a curved lobe 403 to the bottom 41 of the entrance lock 11. The lobe 403 has in the height H of the center of the entrance sluice 1 1 has a thickness D, which is determined by the width B of the opening 209 of the nozzle 17. On the side of the fluid flow curtain 401 facing the inlet opening 213 of the dryer tunnel 5, the fresh air flowing out of the nozzle 17 generates a flow roller 407 of air. In the flow roll 407, the air flows around a center 409 in a flow direction indicated by the arrows 406. The air in the region of the center 409 is substantially stationary. The air circulated in the flow roll 407 is at least partially mixed with the fresh air blown in via the nozzle 17. The flow roll 407 extends from the bottom 41 to the ceiling 6 of the entrance lock 1 first

From the baffle 21 1 on the one hand and the face plate 215, which is arranged on the facing to the input opening 213 side of the baffle 21 1, on the other hand, a diffuser 16 is formed. In this case, the diffuser 16 preferably absorbs part of the air circulated in the flow roller 407 within its mixing chamber 217. In the mixing chamber 217, this becomes Air entrained in a part of the flowing from the opening 209 of the nozzle 17 gaseous fluid in the manner of a Ventu effect and added. This increases the volume flow of the fluid flow curtain 401 in the area of the arrows 402. The volume flow of the fluid flow curtain 401 can thus consist of 30% or more of gaseous fluid which is supplied to the fluid flow flowing out of the nozzle 17 via the mixing chamber 217. As a result, even with a comparatively small amount of injected fresh air, a fluid flow curtain 401 extending to the bottom 41 of the dryer tunnel 5 can be produced.

The air from the mixing chamber 217 is returned to the flow roll 407 in this way. As a result of this process, only a small proportion of the gaseous fluid supplied via the nozzle 17 into the interior 39 of the dryer tunnel 5 leaves through the opening 213 of the lock 11 of the dryer tunnel 5. The flowing from the nozzle 17 gaseous fluid thus passes for the most part in accordance with the direction of the arrows 408 in the interior of the dryer tunnel 5. By means of the gaseous fluid flowing from the nozzle 17 is in the region of the opening 213 of the lock 1 1 a barrier in the Flow roll 407 circulated air generated. This barrier causes a thermal separation of the interior 39 of the dryer tunnel 5 from the outside area. In addition, this barrier also prevents the entry of dust and dirt particles into the interior 39 of the dryer tunnel 5. FIG. 5 shows a modified embodiment of a lock 501 for a drying installation. The lock 501 has a nozzle 503 for supplying fresh air with a modified compared to the lock 1 1 of FIG. 1 nozzle geometry. The nozzle 503 is a dual-chamber nozzle. The nozzle 503 has a slot-shaped nozzle opening 505 and a slot-shaped nozzle opening 507, which extends in each case over the entire width of the ceiling 509 of the entrance lock 501. The nozzle 503 comprises a pivotable control flap 51 1. The control flap 51 1 is closed by means of a not further showed spindle drive movable. For moving the control flap but also an adjusting mechanism with shaft or a cable is suitable. By pivoting the control flap 51 1, the fresh air supplied to the nozzle 503 through the chamber 513 can be selectively directed either through the nozzle opening 507, the nozzle opening 509, or through the nozzle openings 507, 509. This makes it possible to meter the air flow emerging from the nozzle openings 507, 509. For example, it is possible by means of the control flap 51 1 to vary the air flow from the nozzle 503 according to the position of vehicle bodies in the region of the inlet opening of a dryer tunnel. With this measure it can be achieved that a paint layer applied to a vehicle body is not impaired by the fluid flow formed by the fresh air from the nozzle 503. In addition, the thickness D of the fluid flow curtain and thus the quantity and / or the speed of the fresh air fed into the interior of the dryer tunnel can be adjusted with the control flap 51 1.

In a modified embodiment of the entrance lock 501, a nozzle with a plurality of nozzle openings and with a plurality of control valves can be provided to set a fresh air flow for a dryer tunnel.

Fig. 6 shows a portion of an alternative embodiment for a lock 601 having a nozzle 603 for forming an air curtain in the entry or exit area of a drying plant.

The nozzle 603 in the lock 601 is associated with a guide plate 605 which acts as a guide wing and which is preferably pivotably arranged. The baffle optionally has an at least partially curved outer contour. In particular, it extends over the entire width of the nozzle 603. The pivotable baffle 605 at the opening 607 of the nozzle 603 is pivotally mounted on the ceiling 608 of the lock 601 at a pivot 615. The pivotable guide plate 605 protrudes into the interior 61 1 of the lock 601. The length L of the contour of the guide plate 605 corresponds to approximately 20 to 40 times the slot width B of the nozzle opening. The swiveling baffle 605 opposite, in turn, an end wall 609 is disposed in the lock 601. The pivotable guide plate 605 and the end wall 609, together with a ridge element 612, also here define a diffuser with a mixing chamber 613. Due to the pivotability of the guide plate 605, the geometry of the diffuser and the mixing chamber 613 in the lock 601 can be changed. For pivoting the guide plate 605 is associated with a not shown actuator. By pivoting the baffle 605 according to the double arrow 617, it is possible to set an angle β with respect to the horizontal 616 and thus the direction of a generated with gaseous fluid from the nozzle 603 fluid flow curtain in the lock 601. By pivoting the guide plate 605 is displaced, on which the gaseous fluid flowing from the nozzle 607 is guided. As a result, it is possible to change the shape of the flow roll, which is formed on the side of the guide plate 605 facing the opening 619 of the lock 601 due to the fluid flowing out of the nozzle 603. By the baffle 605 is pivoted to the ceiling 608 of the lock 601, a comparatively shallow flow of gaseous fluid into the lock can be effected. By moving the guide plate 605 up and down, the flow direction of the fluid flowing out of the nozzle can be adapted to the position and geometry of vehicle bodies, which are moved through the lock 601 into the interior of the dryer tunnel. Thus, it can be achieved that the fluid flowing out of the nozzle is not deflected by the vehicle bodies to the opening 619 and a paint coat applied to vehicle bodies which is to be dried in the drying tunnel will not be blown and will not be damaged in the drying tunnel.

FIG. 7 shows a portion of another alternative embodiment for a lock 701 having a nozzle 703 for receiving in the inlet or outlet a drying system to form an air curtain. The nozzle 703 opens into a diffuser section, which adjoins the narrowed cross section of the nozzle and thus widens the flow cross section for the fluid. The nozzle 703 with subsequent diffuser section thus has a flow channel 704, the cross section of which extends toward the interior 71 1 of the lock 701 into a volume acting as a diffuser, in which a mixing chamber 713 is located.

Incidentally, the construction of the lock 701 corresponds to that of the lock 601 from FIG. 6. Corresponding assemblies of the lock 601 and 701 are therefore identified in FIG. 7 with reference numerals increased by 100 compared to FIG. Unlike the end wall 609 of the lock 601 in FIG. 6, the lock 701 has an end wall 709 with one or more inlet openings for ambient air. Preferably, the end wall 709 openings in the form of a sieve-like perforation. This measure also makes it possible to draw in air from an upper region 721 in the vicinity of the lock 701. The thus sucked into the lock 701 air is preferably mixed with air from a flow roll, which forms at the opening of the lock. Subsequently, the sucked air and a part of the air from the flow roll are mixed into the fluid flow emerging from the diffuser.

Fig. 8 shows a portion of another alternative embodiment for a lock 801 having an aperture 803 having an aperture 804 for forming an air curtain in the entry or exit area of a dryer. The construction of the lock 801 corresponds to that of the lock 701 from FIG. 7. Corresponding assemblies of the lock 701 and 801 are therefore identified in FIG. 8 with reference numerals increased by 100 compared to FIG. The end wall 809, the ridge member 812 and the baffle 805 also define a diffuser that includes a mixing chamber. Unlike the end wall 709 of the lock 701 in Fig. 7, the end wall 809 of the lock 801 with a recess 816 executed. This measure also makes it possible to take in air from an upper region 821 of the vicinity of the lock 801 into the flow roll generated by the orifice 803 at the opening of the lock.

9 shows a cross section of an entrance or exit lock 901 of a dryer tunnel 900 in a drying installation with a vehicle body 912. The lock 901 has slot-shaped nozzles 903, 905, 907 which are located on the ceiling 910 of the lock 901. The nozzles 903, 905, 907 can be acted upon by a device for supplying fresh air, not shown, with a fresh air stream 909. In the lock 901 there are control valves, by means of which the fresh air stream 909 can be divided into different channels 91 1, 913 and 915 for the separate pressurization of the nozzles 903, 905 and 907 with fresh air.

This measure allows the setting of a fluid flow curtain 917 at the openings of a dryer tunnel, which corresponds to the passage of workpieces, for. B. vehicle bodies over the width B of the opening can be set differently.

10 shows a longitudinal section of another lock 101 1 for a dryer tunnel in a plant for drying metallic workpieces. According to Fig. 4, the flow conditions for air in the lock 101 1 are also indicated here by arrows. The fresh air supplied to the dryer tunnel via the slot-shaped nozzle 1017 causes a fluid flow curtain 1401 on the exit side of the nozzle 1017.

Starting from an opening 1209 of the nozzle 1017, the fluid flow curtain 1401 extends (preferably from fresh air flowing in the direction of the arrows 1402) in the form of a more or less curved lug 1403 in the direction of a bottom 1041 of the lock 101 1. On a side facing the input opening 1213 of the lock 101 1 side of the fluid flow curtain 1401, the fresh air flowing out of the nozzle 1017 generates a flow roll 1407 of air. In the flow roll 1407, the air flows around a center 1409 with a direction of flow indicated by the arrows 1406. The air in the region of the center 1409 is essentially unobstructed. The air circulated in the flow roll 1407 is at least partially mixed with the fresh air blown through the nozzle 1017. The flow roll 1407 extends from the bottom 1041 to the ceiling 1006 of the entrance lock 101 1. The lock 101 1 has on the side facing the input opening 1213 side of an opening 1009 of the nozzle 1017 of a guide contour having baffle 121 1 an arc-shaped ridge wall 1215. The baffle 121 1 and the ridge wall 1215 limit and surround sections a diffuser 1210 with In the embodiment according to FIG. 10, a flow guide element 1218 in the form of a "flow wing" is positioned in the diffuser 1210, which, like the opening 1009 of the nozzle 1017, preferably over the entire width of the lock 101 1 The baffle 121 1 separates the diffuser 1210 from a secondary chamber 1216. The secondary chamber 1216 acts as dead space for air having lower flow velocities than the rest of the lock (except for the actually negligible center of rotation 1409 of the flow roll).

At the bottom 1041 of the lock 101 1, a silhouette wall 1220 is arranged in the region of the opening 1213. Silhouettenwandung 1220 serves in particular as a flow barrier or as a bottom-side flow guide. The silhouette wall 1220 is preferably made of spring steel or other temperature and / or corrosion resistant steels. The silhouette wall 1220 can be pivoted about a (horizontal) axis 1222 according to the arrow 1224. According to the invention, the mixing chamber 1217 absorbs a small part of the air circulated in the flow roll 1407. In the mixing chamber 1217, this air is guided by the flow vane 1218 due to a Venturi effect to the gaseous fluid flowing out of the opening 1209 of the nozzle 17. It is entrained by the gaseous fluid. This increases the volume flow of the fluid flow curtain 1401 in the area of the arrows 1402. The volume flow of the fluid flow curtain 1401 can thus consist to a large extent of gaseous fluid which is supplied to the fluid flow from the nozzle 1017 via the mixing chamber 1217. As a result, even with a comparatively small amount of fresh air blown in, a fluid flow curtain 1401 extending as far as the bottom 1041 of the dryer tunnel can be produced.

The air from the mixing chamber 1217 is in this way fed back to the flow roller 1407. As a result of this process, only a small portion of the gaseous fluid supplied via the nozzle 1017 into the interior 1039 of the dryer tunnel leaves through the opening 1213 of the lock 101 1 of the dryer tunnel. The gaseous fluid flowing out of the nozzle 1017 thus passes for the most part in the direction of the arrows 1408 into the interior of the dryer tunnel. By means of the gaseous fluid flowing out of the nozzle 1017, a barrier is created in the region of the opening 1213 of the lock 101 1 with air circulated in the flow roller 1407, which thermally separates the interior 1039 of the dryer tunnel from the outside area and, moreover, also an entry of dust and dust Dirt particles in the dryer tunnel prevents. The silhouette wall 1220 at the bottom 1041 of the lock 101 1 causes the flow roll 1407 to be comparatively narrow. Only when a workpiece is moved into the drying tunnel is the silhouette wall corresponding to the arrow 1220 briefly folded in the direction of the bottom 1041. It should be noted that alternatively or additionally, a foldable silhouette wall corresponding to the silhouette wall 1220 can also be arranged in the upper region of the entry opening. The installation 2001 for drying vehicle bodies 2003 shown in FIG. 11 has a process chamber in the form of a dryer tunnel 2005. The dryer tunnel 2005 is designed with an inlet lock 201 1, an intermediate lock 2012 and an outlet lock 2013. In the dryer tunnel 2005, the intermediate lock 2012 separates a first drying section 2015a from a further drying section 2015b as receiving areas for the motor vehicle bodies, which is adjoined as a further receiving area for motor vehicle bodies by a holding zone 2016, which is arranged in front of the outlet lock 2013.

The structure of the locks 201 1 and 2013 corresponds to the structure of the entrance or exit lock 1 1, 13 in the plant 1 shown in FIG. 1 for drying. In at least one lock 201 1, 2013, there is a nozzle 2014 for generating a fluid flow curtain 2021 of fresh air, which is directed obliquely into the interior of the dryer tunnel 2005. One or more nozzles 2014 are combined with a diffuser 2018, in particular the diffuser is located adjacent to the nozzle outlet and is formed asymmetrically to a main flow plane through the associated nozzle. By means of an asymmetric diffuser at the nozzles of the inlet and outlet locks 201 1, 2013 can be generated on a side facing the opening 2015, 2017 of the dryer tunnel 2005 side of the fluid flow curtain in each case a flow roll of air, on the one hand from a line 2019 via the nozzles 2014 injected fluid and ambient air at the openings 2015, 2017 consists. The intermediate lock 2012 has a nozzle 2009, which generates a fluid flow curtain 2020.

A modified embodiment of the plant 2001 can also be carried out without asymmetric diffusers in the nozzles, such as when the tightness of the locks reduced demands are made. For example, a mechanical closing of the corresponding locks can be provided. The plant 2001 contains a heating device 2023 designed as a device for the thermal exhaust air purification with a line 2025 for supplying hot clean gas from the drying tunnel 2005 and a heat exchanger 2027, which serves for heating exhaust air from the drying tunnel 2005. The exhaust air heated out of the dryer tunnel 2005 in the heat exchanger 2027 can be combusted in a combustion chamber 2029 of the heater 2023 with or without the addition of additional fuel.

The heater 2023 supplies heat to a plurality of heat transfer devices 2031, 2033, 2035, 2037 through a hot gas line 2036 acting as a clean gas line. The heat transfer devices 2031, 2033 and 2035 are coupled in a row one behind the other to the hot gas line 2036. The heat transfer devices 2031, 2033, 2035 are preferably carried out largely similar. The device 2037 includes an air / air heat exchanger and is coupled as the last of the heat transfer devices to the hot gas line 2036. The device 2037 is used for the temperature control of the fresh air, which is led to the nozzles 2014 for the generation of the fluid flow curtain 2021 from fresh air. The devices 2031, 2033 and 2035 each contain a heat exchanger 2039 connected to the hot gas line 2036 with a hot gas line 2038 and are designed for circulating circulating air in the drying sections 2015a, 2015b and in the holding zone 2016. In the heat exchangers 2039, the circulating air is tempered by a recirculating air duct system 2041 communicating with the receiving areas 2015a, 2015b and 2016 with a recirculation return duct 2041a for extracting circulating air from the drying tunnel 2005 and a circulating air supply duct 2041b for introducing circulating air into the drying tunnel 2005 is led.

In the 2001 annex there are facilities 2043 for the supply of additional fresh air to the receiving areas of the dryer tunnel 2005. Directions 2043 have conduits 2045 communicating with a containment area in the dryer tunnel 2005 and including a flow control device 2047 configured as a throttle. It should be noted that the flow control device 2047 may alternatively or additionally also be equipped with a blower. Fresh air is supplied to the devices 2031, 2033, 2035 via the lines 2045 when the fresh air supplied through the nozzles 2014 to the dryer tunnel 2005 is insufficient to cover the fresh air requirement within the dryer tunnel.

The plant 2001 contains a control device 2046. The control device 2046 is connected to a first device 2051 for detecting a state parameter of the drying chamber 2005 acting as a process chamber in the plant 2001. In the device 2051, adjustment of the butterfly valves 2052, 2055 in the lines 2038 for passing hot gas through the heat exchangers 2039 and adjustment of the butterfly valves 2047 in the lines 2045 for supplying fresh air by means of potentiometers or limit switches are detected. From this, it is possible to determine a quantity of fluid supplied to the drying tunnel 2005 per unit of time using the devices 2031, 2033, 2035 and 2037. In this way, optionally, a quantity of heat supplied with the fluid can again be ascertained if the fluid temperatures are measured via temperature sensors assigned via the lines of a circulating-air line system 2041 and a line 2045.

In addition, the control device 2046 is connected to a second device 2053 for detecting a state parameter of the drying chamber 2005 acting as a process chamber in the installation 2001. The device 2053 is designed as a body counting device with which the number of motor vehicle bodies 2003 moved per time unit into the drying tunnel 2005 and thus the quantity of the motor vehicle bodies 2003 arranged in the drying tunnel 2005 can be determined. The controller 2046 is also connected to a temperature sensor 2007 for detecting the hot gas temperature T _A in the hot gas line 2036. The temperature sensor 2007 is used for measuring the temperature of the flowing through the hot gas line 2036 hot gas outlet side of the heat transfer device 2037, with the hot gas from the plant 2001 is released as pure gas to the environment (clean gas above-roof temperature).

The control circuit 2046 is connected to a control module 2056 for adjusting the rotational speed of a fan 2057 arranged in the conduit 2025 and another control module 2059 for adjusting the rotational speed of a fan 2061, which is used to draw fresh air into the conduit 2019 serves a fluid curtain 2021 producing nozzles 2009 in the dryer tunnel 2005.

The flow control devices 2047 in the means 2043 for supplying fresh air and the speed of the fan 2057 are then determined by means of the control circuit 2046 as a function of the value determined by means 2051 for the amount of heat supplied to the dryer tunnel 2005 per unit time and the number determined by means 2053 set in 2003 arranged in the interior of the dryer tunnel 2005 bodies.

By means of the fan 2061, so much fresh air is always supplied into the line 2019 that the locks 201 1, 2012 and 2013 are sealed by means of the fluid flow curtain 2021 generated with the nozzles 2009.

It should be noted that the control device 2046 can basically also be designed as a control loop. In addition, it should be noted that the supply of fresh air by the heat transfer devices 2031, 2033, 2035 into the dryer tunnel 2005 can also be controlled by a control device 2046 which has one or more of the following supplied measured variables as process chamber operating state parameters for the plant 2001:

Release of solvent into the atmosphere in the receiving areas of the dryer tunnel 2005;

Total carbon content in the receiving areas of the dryer tunnel 2005;

Number of bodies arranged in the receiving areas of the drying tunnel;

Temperature of the hot gas generated by the heater 2023 in the hot gas line 2036 behind the device 2037 in front of an exhaust chimney;

Temperature difference of the circulating air before and after the devices 2031, 2033 and 2035;

Temperature difference of exhaust air from the dryer tunnel, which is supplied to an exhaust gas purification system, and exhaust air, which exits the exhaust gas purification system through an exhaust air chimney;

The weight of a body or the size of a body surface covered with paint, in order to deduce an amount of solvent. It is advantageous if a plurality of measured variables are combined in the control device 2046 as a state parameter (process chamber operating state parameter). So z. B. also detected by the temperature sensor 2007 clean gas above-roof temperature as primary measure and an adjustment of the throttle 2052, 2055 for adjusting the hot gas flow in the hot gas lines 2036, 2038 (clean gas flap position) as a secondary measure be recorded. The primary measured variable serves to determine a fresh air - exhaust air volume flow and the secondary measured variable of the verification, confirmation and / or, if necessary, correction of this fresh air-exhaust air volume flow.

After determining the fresh air-exhaust air volume flow through the clean gas-above-roof temperature then z. B. a review of this Current based on the secondary measured variable. For example, the variable fresh air volume flow is kept constant or increased until the positions of all clean gas flap positions are again below a predetermined value, when the position of the clean gas flap positions exceeds said predetermined value, which depends on the overall system and between 50 % and 100% opening degree can be. In particular, it can be ensured with such a combination of several measured variables that a sufficient amount of heat is contained in the dryer tunnel 2005 of the plant 2001.

The attachment 2001 can be operated in particular as follows:

In a first operating mode, which corresponds to a load state A of the system 2001 of, for example, A <50% based on the maximum possible capacity of workpieces in the process chamber designed as a dryer tunnel, a constant fresh air volume flow through the locks 201 1, 2012 and / or fed in 2013. An additional supply of fresh air via the lines 2045 into the process chamber does not necessarily have to take place here.

In a second operating mode, which corresponds to a load state A of the system 2001 of, for example, 51% <A <90% with respect to the maximum possible capacity of workpieces in the process chamber designed as a dryer tunnel, a constant fresh air volume flow is achieved via the locks 201 1, Fed in 2012 and / or 2013. At the same time, additional fresh air is introduced into the process chamber by opening flow control devices 2047 configured as throttle valves in the lines 2045 via the heat exchanger devices 2031, 2033, 2035 and / or 2037.

In a third operating mode, which corresponds to a state of utilization of the plant 2001 of, for example, 91% <A <100% with respect to the maximum possible capacity. In the heat exchanger devices 2013, 2033, 2035 and / or 2037, a constant fresh air volume flow is supplied via the locks 201 1, 2012 and / or 2013, and the flow in the heat transfer devices 2013, 2033, 2035 and / or 2037 supplied additional fresh air by additional with respect to the second mode opening of the flow control devices 2047 further increased.

It should be noted that the system 2001 can also be operated in other operating modes in which the flow control devices 2047 in the lines 2045 have a different opening position with respect to the aforementioned operating modes. In particular, a stepless change in the operating mode of the plant 2001 is basically possible.

In particular, it should be noted that the feeding of fresh air into the drying tunnel 2005 in the plant 2001 can also take place at other locations than are shown in FIG. 11:

In an alternative embodiment of the plant 2001 z. B. provided that in the receiving areas 2015a, 2015b, 2016 of the dryer tunnel 2005 circulating air and / or fresh air through openings in the wall, in the ceiling and / or in the bottom of the dryer tunnel 2005 is supplied. The feeding of fresh air into the circulating air duct system 2041 can also be carried out in a device 2001 described above, also in relation to the flow direction of the circulating air, before or after a heat exchanger 2039 in a heat transfer device 2031, 2033, 2035. It should also be noted that the supply of fresh air is possible both inside a heat transfer device 2031, 2033, 2035 and outside of a heat transfer device 2031, 2033, 2035 in a recirculation return duct 2041 a or recirculation return duct of a recirculating air duct system 2041. In order to set a defined volume flow for the fresh air, a fan can also be arranged in the line 2045 for fresh air. In addition, it is possible that the fresh air on the side facing the interior of the dryer tunnel 2005 side of a fluid flow curtain 2021 in a lock 201 1, 2013, 2015 of the plant 2001 is supplied.

In order to explain the above-mentioned alternative embodiments of the installation 2001, further drying installations according to the invention are described below with reference to FIGS. 12 to 19:

FIG. 12 shows a further installation 2001 'for drying vehicle bodies 2003, which fundamentally corresponds in its construction to the installation 2001 from FIG. Insofar as the assemblies in the plant 2001 of FIG. 11 and in the plant 2001 'of FIG. 12 are identical, they have the same reference numerals in FIG. 11 and FIG. In the plant 2001 ', the line 2045 for supplying fresh air into the recirculating air system 2041 via a branch 2045a and a branch 2045b in the heat transfer device 2037 is connected to the line 2019 for supplying fresh air to the nozzles 2009. Through the line branch 2045a, it is possible to feed fresh air drawn in by means of the fan 2061 into the line 2045, which was heated in the heat exchanger 2039 of the heat transfer device 2031 with heat from the clean gas guided in the hot gas line 2036. Alternatively or additionally, fresh air can also be conveyed through the line branch 2045b in the heat transfer device 2037 into the line 2019 by means of the fan 2061 into the line 2045. In this case, the fresh air conveyed by means of the fan 2061 is then not or only partially guided through the heat exchanger 2039 in the heat transfer device 2037. The guided in the line 2019 fresh air is introduced in the plant 2001 'in the heat transfer devices 2031, 2033 and 2035 so that it passes through the arranged in the heat transfer devices 2031, 2033 and 2035 heat exchanger in the dryer tunnel 2005.

The introduced into the heat transfer devices 2031, 2033 and 2035 fresh air from the line 2045 can thus be heated with heat from the guided in the hot gas line 2036 clean gas. In the line section 2019a of the system 200Γ a flow measuring device 2062 is arranged. The flow meter 2062 controls an actuator in a flow control device 2048. Thus, it can be ensured in the system 200Γ that for different speeds of the fan 2061 the nozzles 2009, 2014 for generating a fluid flow curtain 2020, 2021 are supplied with a constant fresh air flow. In line 2045, a flow meter 2063 is arranged. The flow meter 2063 is for determining the amount of fresh air fed into the conduit 2045 by means of the fan 2061.

In the system 200Γ, fresh air flow fed into the line 2045 via the flow control device 2048 is set as a function of the number of bodies 2003 arranged within the dryer tunnel 2005 as determined by the device 2053.

The flow measuring devices 2062, 2063 determine the amount of fresh air fed into the line 2019, 2045 by means of the fan 2061 by detecting the pressure drop at a diaphragm arranged in the line section with the flow meter 2062, 2063. It should be noted that the flow meter 2062, 2063 for detecting the flow of fresh air may alternatively include a magnetic inductive sensor, an ultrasonic measuring unit or an impeller. 13 shows a further installation "for drying, the construction of which is essentially identical to the construction of the installation 2001 described above." As far as the assemblies are functionally identical in the installations shown in FIG. 12 and FIG. these have the same numbers in FIG. 12 and FIG. 12 as reference numerals.

In contrast to the system 2001 'of FIG. 12, in the installation 2001 ", the fresh air is fed to the heat exchanger 2039 on the outlet side through the line 2045 for the supply of fresh air in the heat transfer devices 2031, 2033 and 2035 Heat exchanger 2039 of a heat transfer device 2031, 2033, 2035 is then heated only by a feed channel 2041 a supplied circulating air from the dryer tunnel 2005.

14 and 15 show further installations 2001 "" and 2001 "" for drying, the construction of which corresponds to the structure of the installation described with reference to Figures 12 and 13. Functionally identical subassemblies in these installations again have the same characteristics In the system 200V ^" fresh air is introduced via the line 2045 outside the heat transfer devices 2031, 2033 and 2035 in the return air return passage 2041 b of the line system. In the plant 2001 ^"" , the line 2045 for supplying fresh air into the drying tunnel 2005 is connected to a recirculation return suction channel 2041 a of the line system 2041, through which the recirculated air from the drying tunnel 2005 into a heat transfer device 2031, 2033 and 2035 is performed.

It should be noted that in a modified embodiment of the system 200Γ ^" of Fig. 14 or 2001 ^"" of Fig. 15 may also be provided fresh air from a line 2045 both in a recirculation return duct 2041 a and a recirculation return duct 2041 b a Umluftleitungssys- feed in 2041. If the fresh air is fed to a recirculation return duct 2041 b, however, it must be ensured that the fresh air in question is heated. The installation 3001 for drying vehicle bodies 3003 shown in FIG. 16 has a plurality of temperature sensors 3070, 3072, 3074 and 3076 as means for detecting a condition parameter of a dryer tunnel 3005 acting as a process chamber. Insofar as the assemblies in the installation 3001 belong to the assemblies in the system 1, are functionally indicated in FIG. 12 with numbers increased by the number 1000 in relation to FIG. 11, as reference symbols.

The temperature sensors 3070, 3072, 3074 and 3076 are connected to the controller 3046. The temperature sensor 3070 is disposed in the hot gas line 3026 between the heater 3023 and the heat transfer device 3031. The temperature sensor 3072 is located in an end portion of the hot gas duct 3026 from which the clean gas flowing through the hot gas duct 3026 enters the environmental atmosphere. The temperature sensors 3070, 3072 are used for determining the heat emitted by the clean gas flowing through the hot gas line 3026 into the dryer tunnel 3005 by determining the difference Δ mittels _Η = T _I -T ₂ by means of these temperature sensors. The temperature sensors 3074 and 3076 determine the difference between the temperatures ΔΤυ: = T ₃ -T from circulating air flowing out of the dryer tunnel 3005 in the recirculating return suction channel 3041 a and fresh air mixed with fresh air, which is conducted through the recirculating air supply channel 3041 b into the dryer tunnel 3005.

The control device 3046 controls the rotational speed of the fan 3057 in the conduit 3025 and the adjustment of the flow control devices 3047 for adjusting the amount of fresh air fed into the conduit system 3041 as a function of the temperature difference ΔΤ _Η , ΔΤυ detected by the temperature sensors 3070, 3072, 3074 and 3076 , Alternatively to this For example, the controller 3046 may also be implemented as a control loop that controls the speed of the fan 3057 in the conduit 3025 and the adjustment of the flow controller 3047 based on the signal from the temperature sensors 3070, 3072, 3074 and 3076.

The system 4001 for drying vehicle bodies 4003 shown in FIG. 17 has as its means for detecting a condition parameter of a dryer tunnel 4005 acting as a process chamber a scale 4078 for determining the mass of vehicle bodies 4003 fed to the dryer tunnel 4005 of the system 4001 correspond to the modules in the system 2001 of FIG. 1 1 functionally, these are in FIG. 13 with respect to FIG. 1 1 increased by the number 2000 numbers identified as reference numerals. Here, the controller 4046 controls the rotational speed of the fan 4057 in the conduit 4025 and the adjustment of the flow control devices 4047 for adjusting the amount of fresh air fed into the piping 4041 depending on the mass of the vehicle bodies 4003 supplied to the dryer tunnel 4005 by the balance 4078.

FIG. 18 shows a system 5001 for drying vehicle bodies 5003. Insofar as the modules in the system 5001 functionally correspond to the modules in the system 2001 from FIG. 11, these are shown in FIG. 17 with reference to FIG 1 numbers increased by the number 3000 identified as reference numerals. In the system 5001, the line 5045 for supplying fresh air in the heat transfer device 5037 receives fresh air, which can be heated by means of the heat exchanger 5039 with heat from clean gas guided in the hot gas line 5026. The fresh air from the line 5045 is introduced in the system 5005 in the locks 501 1, 5012 and 5013 of the dryer tunnel. FIG. 19 shows a system 6001 for drying vehicle bodies 6003. Insofar as the modules in the system 6001 functionally correspond to the modules in the system 6001 from FIG. 19, these are shown in FIG. 19 with reference to FIG the number 1000 increased numbers indicated as reference numerals. In the plant 6001, the fresh air from the line 6045 is introduced into the drying sections 6015a, 6015b and the holding zone 6016 of the dryer tunnel 6005.

Further modifications and further developments of a system according to the invention can result inter alia by combining various features of the above-described advantageous embodiments.

In summary, the following preferred features of the invention are to be noted: A process chamber 5, 2005 has an interior 39 with a receiving area 15, 2015a, 2015b, 2016 for workpieces 3, 2003. The process chamber 5, 2005 has an opening 12, 14, 2015, 2017 for the supply or removal of workpieces 3, 2003. The process chamber 5, 2005 is formed with a device 17, 19, 25, 29, 33, 37, 35, 2014 for the injection of gaseous fluid into the interior 39, the at least one Nozzle 17, 19, 2014 or aperture 803 for generating a fluid flow curtain 21, 23, 2021 between the opening 12, 14, 2015, 2017 and the receiving area 15, 2015a, 2015b for workpieces 3, 2003 has. The process chamber 5, 2005 has a device 74, 2043 for supplying fresh air, with the on a side facing away from the opening 12, 14, 2015, 2017 side of the fluid flow curtain 21, 23, 2021 introduced into the receiving area 15, 2015a, 2015b fresh air can be. LIST OF REFERENCE NUMBERS

1 plant

3 vehicle body

5 drying tunnel, process can

6 ceiling

7 Skid

9 conveyor

10 drive

1 1 entrance lock

12 inlet opening

13 exit lock

14 outlet opening

15 drying section, drying zone

16, 18 diffuser

17, 19 nozzle

17, 19, device

21, 23 Fluid curtain

25, 27 fresh air

29, 31 chamber

33, 35 opening

37 horizontal

39 interior

41 soil

42 ambient air

43, 44 heating device

45, 47 control device

49, 51 sensor

61 fan

74, 74 Facility

63 heating device

69, 71 Temperature sensor 70 establishment

72 recirculation system

73 solvent sensor

74 establishment

75 flow channel

76, 76 'line

77 return channel

78, 78 'opening

80, 80 'flow control device 201 piping

202 main flow level

203 chamber

204 level

205 air filter

206 housing plate

207 baffle

208 axis of rotation

209 opening

210 fluid flow

21 1 Guiding contour, contour, guide plate

213 entrance opening

215 front wall, front plate

216 secondary chamber

217 mixing chamber

219 fluid

401 fluid flow curtain, fluid present

402 arrow

403 club

406 arrow

407 flow roll

408 arrow

409 center 501 lock, entrance lock

503 nozzle

505 nozzle opening

507 nozzle opening

509 ceiling

507, 509 nozzle openings

51 1 control flap

601 lock

603 nozzle

605 baffle

607 opening, nozzle

608 ceiling

609 front wall

61 1 the interior

612 ridge element

613 mixing chamber

615 swivel joint

616 horizontal

617 double arrow

619 opening

701 lock

703 nozzle

704 flow channel

709 front wall

71 1 the interior

713 mixing chamber

721 area

801 lock

803 aperture

804 opening

805 baffle

809 front wall 812 ridge element

816 recess

821 area

900 drying tunnels

901 lock, exit lock

903, 905, 907 nozzle

909 fresh air flow

910 ceiling

91 1, 913, 915 channel

917 fluid flow curtain

006 ceiling

1009 opening

101 1 lock, entrance lock

1017 nozzle

1039 interior

1041 floor

1209 opening

1210 diffuser

121 1 baffle

1213 opening, entrance opening

1215 ridge wall

1216 secondary chamber

1217 mixing chamber

1218 flow guide, flow wing

1220 silhouette wall, arrow

1222 axis

1224 arrow

1401 fluid curtain

1402 arrow

1403 club

1406 arrow

1407 flow roll 1408 arrow

1409 center, center of rotation

2001, 2001 ', 2001 ",

2001 "', 2001" "attachment

2003 vehicle body, workpiece

2005 drying tunnel, process can

2007 temperature sensor

2009 nozzle

201 1, 2012, 2013, 2015 lock

2014 nozzle

2015a, 2015b drying section, reception area

2015, 2017 opening

2016 holding zone

2018 diffuser

2019 management

2019a line section

2020 fluid flow curtain

2021 fluid flow curtain

2023 heating device

2025 line

2027 heat exchanger

2029 combustion chamber

2031, 2033, 2035 heat transfer device

2036, 2038 hot gas line

2037 heat transfer device

2039 heat exchanger

2041 recirculation system

2041 a Recirculation intake duct

2041 b Recirculation air supply duct

2043 establishment

2045 line

2045a, 2045b line branch 2046 taxation

2047, 2048 Flow control device 2049 control circuit

2051, 2053 establishment

2052, 2055 throttle

2056, 2059 control module

2057, 2061 fan

2062, 2063 Flowmeter 3001 System

3003 vehicle body, workpiece 3005 drying tunnel, process can 3023 heating device

3025, 3045 pipe

3026 hot gas line

3031 heat transfer device

3041 pipe system

3041 a Recirculation intake duct

3041 b Recirculation air duct

3046 control device

3047 throttle valves

3057 fan

3070, 3072, 3074 and 3076 temperature sensor

4001 plant

4003 vehicle body, workpiece 4005 dryer tunnel, process can

4025, 4045 line

4041 pipe system

4046 control device

4047 throttle

4057 fan

4078 Libra

5001 plant 5003 vehicle body, workpiece

501 1, 5012 and lock

5036 hot gas line

5037 heat transfer device

5039 heat exchanger

5041 pipe system

5041 a Recirculation intake duct

5045 line

6001 plant

6005 drying tunnel

6015a, 6015b Drying section 6045 pipe

Claims

claims

1 . Installation (1, 2001) with a process chamber (5, 2005), which has an interior (39) with a receiving area (15, 2015a, 2015b, 2016) for workpieces (3, 2003) and which has an opening (12, 14, 2015

2017) for the supply or removal of workpieces (3, 2003), and with a device (17, 19, 25, 29, 33, 37, 35, 2014) for the injection of gaseous fluid into the interior (39) comprising at least one nozzle (17, 19, 2014) or aperture (803) for creating a flow idler curtain (21, 23, 2021) between the opening (12, 14, 2015,

2017) and the receiving area (15, 2015a, 2015b) for workpieces (3, 2003), characterized by means (74, 2043) for supplying fresh air, with which on one of the opening (12, 14, 2015, 2017 ) on the opposite side of the fluid idstromvorhangs (21, 23, 2021) in the receiving area (15, 2015a, 2015b) fresh air can be introduced.

2. Plant according to claim 1, characterized in that the means (74, 2043) for supplying fresh air at least one with the receiving area (15, 2015a, 2015b) communicating line (78, 2045) containing an opening for the suction of fresh air and has a flow control device (80, 2047).

Installation according to claim 2, characterized in that the flow control device comprises a throttle valve (80, 2047) and / or an adjustable blower.

Installation according to one of claims 1 to 3, characterized by a device (70, 2031, 2033, 2035) for the circulation of gaseous Fluid in the receiving area (15, 2015a, 2015b) by a with the receiving area (15, 2015a, 2015b) communicating Umluftleitungssystem (72, 2041) by a means (2031, 2033) for the tempering, in particular for the heating of gaseous Fluid from the receiving area (15, 2015a, 2015b) is guided.

Installation according to claim 4, characterized in that the device (74, 2043) for supplying fresh air into the receiving area (15, 2015a, 2015b) comprises at least one conduit (76, 2045) with an opening (78) for the intake of fresh air which is connected to the circulating air system (72, 2041) and which comprises a flow control device (80).

Installation according to claim 5, characterized in that the flow control device comprises a throttle valve (80, 2047) and / or an adjustable blower.

Installation according to claim 5 or 6, characterized in that the line (76) opens with the opening (80) for the suction of fresh air in a recirculating return duct (77) in the circulating air duct system (72).

Installation according to one of Claims 2, 3, 5, 6 or 7, characterized in that the flow control device (80, 2047) is connected to a control circuit (45, 2049) which receives the signal from a device (49, 69, 73, 2051) for detecting a state parame- ter of the process chamber (5, 2005), and the amount of fresh air introduced into the receiving area (15) via the means for supplying fresh air by means of the flow control means (80, 2047) depending on controls or regulates at least one detected state parameter. Installation according to claim 8, characterized in that the device (2051) is designed for detecting a state parameter of the process chamber (5, 2005) from the group indicated below: i. Carbon content and / or solvent content of the atmosphere in the reception area (2015a, 2015b, 2016);

ii. Number and / or weight and / or type and / or size of the surface of workpieces arranged in the receiving area (2003);

iii. Number and / or weight and / or type and / or size of the surface of workpieces supplied per unit time (2003);

iv. Temperature of the exhaust air from the combustion chamber (2029) of a burner in a device for tempering circulating air;

v. Temperature difference of gaseous fluid taken from the receiving area (2015a) and returned to the receiving area (2015a);

vi. Temperature difference of gaseous fluid from the receiving area (2015a) supplied to a combustion chamber (2029) of a burner in a means for controlling circulating air and exhaust air from the combustion chamber (2029) of the burner;

vii. Amount of heat per unit time, which is the process chamber (2005) supplied.

Installation according to one of claims 1 to 9, characterized in that the receiving area in a first receiving area (2015a) and a further receiving area (2015b) is divided and the device (2014) for the injection of gaseous fluid into the interior of the fluid flow curtain (2021 ) is generated between the first receiving area (2015a) and the further receiving area (2015b).

1 1. Installation according to one of claims 1 to 10, characterized in that the interior (39) is designed tunnel-shaped and has a bottom (41) and a ceiling (6), wherein the at least one nozzle (17, 19) or aperture (803) has a slit shape which obliquely slices the gaseous fluid over the ceiling (6) with respect to the floor (41)

Flow direction (402) in the interior (39) feeds, and in the interior (39) supplied gaseous fluid on the opening (12, 14) facing side of the fluid flow curtain (21, 23) generates a flow roller (407) made of air at least partially mixed with injected fluid.

12. Plant according to claim 1 1, characterized in that in the interior (39) supplied gaseous fluid is fresh air. 13. Plant according to claim 1 1 or claim 12, characterized in that the at least one nozzle (17, 19) or aperture (803) in the interior (39) injected gaseous fluid through a diffuser (16, 21 16) in the interior (39) is guided. 14. Plant according to claim 13, characterized in that the guide contour (606) on a pivotable guide vanes (605) is formed.

15. Plant according to claim 13 or 14, characterized in that on the side facing the opening (213, 1213) side of the guide contour (21 1, 121 1) has a wall (215, 1215) is arranged with the Leitkontur

(21 1, 121 1) defines a diffuser (16, 18) with a mixing chamber (217, 1217) in which fluid from the flow roll (407, 1407) is mixed with air from the region of the opening (213, 1213). 16. Plant according to claim 15, characterized in that from the mixing chamber (407, 1407) mixed fluid from the through the nozzle (17, 19, 1017) or the aperture (803) flowing, gaseous fluid in the interior (39, 1039) is sucked.

Plant according to claim 15 or 16, characterized in that the wall (709, 809) has one or more openings (816) for the passage of circulated air from the region of the opening (213).

18. Plant according to one of claims 15 to 17, characterized marked, that on one of the mixing chamber (217) facing away from the

Guiding contour (21 1) acting as a dead space for gaseous fluid secondary chamber (216) is formed.

19. Plant according to one of claims 15 to 18, characterized marked, that in the mixing chamber (1217) a guide vanes (1218) is arranged, which is supplied with gaseous fluid from the flow roll (1407) and the fluid from the flow roll (1407) returns to the fluid flow curtain (1401). 20. Plant according to one of claims 1 to 19, characterized in that the at least one nozzle (503) has a device (51 1) for adjusting the through the nozzle (503) passing through flow rate for fluid and / or that a plurality of nozzles (50 903, 905, 907) are provided with means for adjusting the flow rate of fluid passing through the nozzle to set the fluid flow curtain between the input port and the workpiece receiving area (912) differently in different sections. 21. Installation according to one of claims 1 to 20, characterized in that for controlling a flow formed in the interior space (1039). idströmung a pivotable flow barrier (1220) is provided.

22. Plant according to one of claims 1 to 21, characterized in that the device for the injection of gaseous fluid has a heater (43, 44) for heating the gaseous fluid.

23. Plant according to one of claims 1 to 22, which is designed as a drying and / or curing plant and / or paint shop.

24. A method of operating a plant according to one of claims 1 to 22, wherein for generating the fluid flow curtain (21, 23, 2021) pressurized gaseous fluid through the nozzle (17, 19) or aperture (803) is guided and in which in one to the nozzle (17,

19) adjacent mixing chamber (217) air from the region of an opening (213) or the interior (39) of the process chamber (5) from the nozzle (17, 19) flowing gaseous fluid is mixed.

25. The method according to claim 24, characterized in that the through the nozzle (17, 19) guided gaseous fluid at a mixing chamber (217) limiting guide contour (21 1) is guided along, which in particular the mixing chamber (217) of a Dead space for gaseous fluid acting adjacent this adjoining secondary chamber (216) separates.

A method of operating a plant as claimed in claim 23 or 24, wherein a flow of gaseous fluid through the nozzle (17, 19) or orifice (803) is provided for creating a fluid flow curtain (21, 23) between the orifice (12, 23). 14) and the receiving area (15) for workpieces (3) is throttled or interrupted and / or in which the Direction of the fluid flow curtain (21, 23) is changed when a workpiece (3) through the opening (12, 14) is moved.

27. The method according to any one of claims 24 to 26, wherein the fluid idstromvorhang (21, 23, 2021) with an averaged over a

Period of constant amount of fresh air is generated, which is passed through the nozzle (17, 19) or the diaphragm (803), and in which the means (74, 2043) for supplying fresh air into the interior (39) in the period a variable amount of fresh air is supplied, which is controlled or regulated as a function of a process chamber operating state parameter from the group indicated below: i. Carbon content and / or solvent content of the atmosphere in the reception area (2015a, 2015b, 2016);

ii. Number and / or weight of workpieces arranged in the receiving area (2003);

iii. Number and / or weight of workpieces supplied per unit time (2003);

iv. Temperature of the exhaust air from the combustion chamber (2029) of a burner in a device for tempering circulating air; v. Temperature difference of gaseous fluid taken from the receiving area (2015a) and returned to the receiving area (2015a);

vii. Amount of heat per unit of time, which is fed to the process chamber (2005).