JP2000205668A - Air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem of shortage of heating capacity which occurs as a working fluid in a heating circuit is released to a cooling circuit, and another problem of worsened energy efficiency which does as the working fluid is released uselessly outside a heating circuit, and, moreover, to quickly achieve a counter measure against an abnormally high pressure when a delivery pressure rises sharply. SOLUTION: There are arranged a compressor 101, a cooling circuit, a heating circuit and delivery capacity altering means 301 and 401, and the compressor 101 has an intake part 115 and a delivery part 120. A working fluid is released to a drive chamber 110 from the delivery part 120 to reduce the delivery capacity, and the delivery capacity altering means 301 and 401 separately make the delivery part 115 communicate with the drive chamber 110. The capacity altering means 301 for cooling combines with the capacity altering means 401 for heating to release the working fluid to the drive chamber 110 from the delivery part 120, when a delivery pressure Pd of the working fluid reaches a high pressure state during the operation of the heating circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner having a cooling circuit and a heating circuit which operate by using a working fluid compressed by a compressor, and more particularly, to a method for reliably and rapidly detecting an abnormally high discharge pressure of a working fluid. The present invention relates to an air conditioner for suppressing air pollution.

[0002]

2. Description of the Related Art An example of this type of air conditioner is disclosed in Japanese Unexamined Patent Publication No.
No. 9630. As shown in FIG. 1, this air conditioner includes a compressor 1, a cooling circuit 51, a heating circuit 52, and a control device 83. The cooling circuit 51
The compressor 1 includes a condenser 55 provided on a path from a discharge part D to a suction part S of the compressor 1, a first expansion valve 57, and a heat exchanger 59. -The high-pressure working fluid is supplied to the compressor 1 via the above devices.
And this cycle is repeated. Heating circuit 52
Is composed of a bypass passage 52a from the discharge part D of the compressor 1 to the heat exchanger 59, a second expansion valve 63 provided on the bypass passage 52a, and the heat exchanger 59, The high-temperature and high-pressure working fluid discharged from the machine 1 is sucked into the compressor 1 via the second expansion valve 63 and the heat exchanger 59 without being sent to the condenser 55, and this cycle is repeated. The heating circuit 52 is generally called a hot gas bypass heater. Switching between the cooling circuit 51 and the heating circuit 52 is performed by switching valves 53a and 53.
The opening / closing operation is performed by the controller 83.

In this type of air conditioner, when the heating circuit 52 is operated, the discharge pressure of the working fluid is higher than when the cooling circuit 51 is selected. Therefore, during the operation of the heating circuit 52, the discharge pressure tends to be abnormally high due to, for example, a temporary increase in the rotation speed of the compressor 1. Therefore, in the related art, a working fluid discharge passage 91 further provided with a pressure relief valve 93 is provided. The working fluid discharge passage 91 includes a heating circuit 52 and a cooling circuit 5.
The pressure relief valve 93 is opened to discharge the working fluid to the cooling circuit 51 side when the discharge pressure of the working fluid becomes abnormally high during the operation of the heating circuit 52. This prior art includes a cooling circuit 51 and a heating circuit 5.
Paying attention to the fact that 2 is selectively selected by the switching valves 53a and 53b, when the discharge pressure becomes abnormally high during the operation of the heating circuit 52, the working fluid is discharged to the unused cooling circuit 51 side. By doing so, abnormal high pressure is not applied to the heating circuit 52.

[0004]

Focusing on the fact that the discharge pressure of the working fluid decreases when the discharge capacity of the compressor decreases, the cooling disclosed in Japanese Patent Application Laid-Open No. 7-19630 is disclosed. An air conditioner having a heating circuit and a heating circuit is disclosed in Japanese Patent Application Laid-Open No. H10-472.
Japanese Patent Application Laid-Open No. 7-19630 discloses a technique for countermeasures against abnormally high discharge pressure during heating circuit operation in Japanese Patent Application Laid-Open No. 7-19630.
That is, the working fluid in the heating circuit is discharged to the cooling circuit and the heating capacity is insufficient, and the energy efficiency is low because the working fluid that is caused to work by the compressor and is discharged to a high pressure is wasted. It is expected that such problems can be solved. In other words, in the variable displacement compressor, the discharge pressure can be reduced by reducing the amount of work, so there is no need to discharge the working fluid to an unused cooling circuit as a measure against abnormally high pressure, and to drive the pressurized working fluid. Although the energy is released into the chamber, the energy is slightly reduced, but there is no waste of discharging the working fluid out of the circuit.

However, the above-described countermeasures against abnormally high pressure by the variable displacement compressor include "opening the capacity control valve to discharge the working fluid from the discharge section to the drive chamber" and "discharge by increasing the pressure in the drive chamber by the discharge." The discharge time of the working fluid is reduced per unit time of the working fluid discharged into the drive chamber. It largely depends on the amount of release, and a predetermined time is required from the start of release until the discharge pressure decreases. For this reason, when the discharge pressure rises rapidly in a short time, the countermeasures against abnormal high pressure cannot be made in time, and the discharge pressure may temporarily exceed the reference value. Particularly, in the hot gas bypass heater, the allowable range between the reference value and the upper limit value is narrow because a higher pressure is used than in the cooling circuit in order to secure the heating capacity,
Even if the discharge pressure temporarily exceeds the upper limit, problems such as damage to circuit components can easily occur, so even if the discharge pressure rises rapidly in a short time, quickly and reliably take measures against abnormal high pressure. Need to take.

The present invention is directed to an air conditioner disclosed in Japanese Patent Application Laid-Open No. 7-19630 by applying a discharge capacity control technique of a conventional variable displacement compressor to an air conditioner having a hot gas bypass heater circuit. The problem of the abnormal high pressure countermeasure technology, that is, the problem that the working fluid in the hot gas bypass heater circuit is released to the cooling circuit and the heating capacity is insufficient, and the working fluid that has been pressurized to high pressure by causing the compressor to work. It solves the problem that energy efficiency is poor due to wasteful discharge outside the heating circuit, and furthermore, a conventional variable displacement compressor is used for an air conditioner equipped with a hot gas bypass heater circuit and a cooling circuit. It is said that there is a problem that may occur in the case, that is, when the discharge pressure rises rapidly, measures against abnormally high pressure of the hot gas bypass heater circuit may be delayed. It is an object of the present invention to solve together the problem.

[0007]

Means for solving the above problems are described in the inventions described in the respective claims.

In the air conditioner of the first aspect, a so-called variable capacity compressor is used as a drive source for operating the cooling circuit and the heating circuit. Further, a so-called hot gas bypass heater is used in a heating circuit in the present air conditioner. In the hot gas bypass heater, it is preferable to provide a decompression device such as an expansion valve in a bypass from the discharge section to the heat exchanger. In this variable displacement compressor, a drive means capable of reducing the discharge capacity by increasing the pressure in the drive chamber is used. When the discharge capacity decreases, the discharge pressure of the working fluid decreases. Conversely, when the discharge capacity increases, the discharge pressure of the working fluid increases. The present air conditioner is configured to increase the pressure in the drive room by discharging a high-pressure working fluid from the discharge section to the drive room.

[0009] The reduction of the suction pressure tends to be a problem especially when the cooling circuit is operated. This is because if the suction pressure is too low, frost may form on the heat exchanger in the cooling circuit. on the other hand,
During operation of the heating circuit, frost formation in the heat exchanger does not pose a problem, so that it is not necessary to take measures for abnormally low suction pressure. On the other hand, an increase in the discharge pressure tends to be a problem particularly during the operation of the heating circuit. In the heating circuit, the operating pressure is set high to ensure the heating capacity, so the range between the normal operating pressure and the upper limit pressure of the circuit is narrow, and even if the discharge pressure slightly increases from the set pressure, the upper limit pressure is reached. Since the hot gas bypass heater has a configuration in which a bypass circuit is provided in the cooling circuit to form a heating circuit, the circuit capacity is small, and the degree of increase in the discharge pressure is likely to be sharp. This is because it is necessary to strictly take measures against abnormally high discharge pressure. On the other hand, when the cooling circuit is activated, a lower operating pressure is used than when the heating circuit is activated. It is not necessary to take strict measures against abnormally high discharge pressure such as hot gas bypass heaters.

In this air conditioner, when the suction pressure of the working fluid becomes a predetermined low pressure state during the operation of the cooling circuit, the first
The capacity changing means communicates the discharge section with the drive chamber. As a result, the working fluid is discharged from the discharge section on the high pressure side to the drive chamber on the low pressure side, and the pressure in the drive chamber increases. Then, the discharge capacity decreases and the suction pressure of the working fluid increases. This effectively prevents problems such as frost formation in the heat exchanger provided in the cooling circuit. On the other hand, when the discharge pressure of the working fluid reaches a predetermined high pressure state during the operation of the heating circuit, the discharge unit and the drive chamber are connected via both the first capacity change means and the second capacity change means arranged in parallel. And communicate with. That is, the working fluid is discharged from the discharge unit to the drive chamber via the two paths as a measure against abnormal high pressure when the heating circuit is operated, and the discharge capacity is reduced. Therefore, the discharge time is shortened as compared with the case where the working fluid is discharged to the drive chamber via one path, so that the time required for reducing the discharge capacity and the discharge pressure can be shortened. . As a result, even if the discharge pressure rises rapidly within a short period of time, it is possible to quickly and reliably take measures against abnormal high pressure. Here, the first capacity changing means is configured to include a valve for eliminating an abnormally low suction pressure state during the operation of the cooling circuit, that is, a low pressure control valve (suction pressure control valve) for the cooling circuit, and the second capacity changing means has a second configuration. It is preferable that the capacity changing means has a configuration that includes a valve for eliminating an abnormally high discharge pressure state when the heating circuit is operated, that is, a high-pressure control valve (discharge pressure control valve) for the heating circuit. In this case, if the suction pressure becomes abnormally low when the cooling circuit is activated, the low pressure control valve is opened to release the working fluid from the discharge section to the drive chamber, and when the discharge pressure becomes abnormally high when the heating circuit is activated. Utilizes not only the high-pressure control valve but also the low-pressure control valve, and can eliminate the abnormally high pressure state of the discharge pressure more quickly than when only the high-pressure control valve is used.

According to the air conditioner of the second aspect, the first capacity changing means is provided when the suction pressure of the working fluid becomes a predetermined low pressure state when the cooling circuit is operated, and when the heating circuit is operated. Opens when a predetermined high pressure state is reached
With a valve. The second displacement changing means has a second valve that opens when the discharge pressure of the working fluid reaches a predetermined high pressure state during the operation of the heating circuit. When the suction pressure becomes abnormally low during the operation of the cooling circuit, the first valve is opened, so that the discharge unit and the drive chamber are connected. As a result, the working fluid is discharged from the high-pressure side discharge section to the low-pressure side drive chamber via the first capacity changing means. As a result, the discharge capacity is reduced and the suction pressure of the working fluid is increased. The abnormally low suction pressure state at the time is eliminated. Also, when the discharge pressure becomes abnormally high during the heating circuit operation, both the first and second valves are opened, so that the discharge unit and the drive chamber are connected. As a result, the working fluid is discharged from the high-pressure side discharge section to the low-pressure side drive chamber via both the first and second volume changing means, and as a result, the discharge capacity decreases and the discharge pressure of the working fluid decreases. . In this case, the working fluid is discharged to the drive chamber through two paths, so that the discharge capacity and the discharge pressure are rapidly reduced.
Therefore, even if the discharge pressure suddenly rises in a short time, there is no possibility that the countermeasure against abnormal high pressure will be delayed.

[0012] In the air conditioner according to the third aspect, in the air conditioner according to the second aspect, the first and second valves are disposed in the housing of the compressor, so that the structure of the entire apparatus can be simplified. .

According to a fourth aspect of the present invention, in the air conditioner of the second or third aspect, the reference valve opening pressure of the first and second valves can be changed. That is, by appropriately setting the valve opening reference pressure of each valve with respect to the discharge pressure or the suction pressure of the working fluid, the first pressure during the operation of the cooling / heating circuit
And the opening and closing of the second valve can be controlled according to the relationship with the pressure of the working fluid.

According to a fifth aspect of the present invention, in the air conditioner of the fourth aspect, the first valve opens when the suction pressure falls below the valve opening reference pressure, and the second valve opens when the discharge pressure exceeds the valve opening reference pressure. It is configured to open. By the way, the valve opening reference pressure of the first valve when the cooling circuit is activated is set as the lower limit reference value of the suction pressure when the cooling circuit is activated. That is, when the suction pressure of the working fluid is higher than the lower limit reference value, the suction pressure is not in an abnormally low pressure state, and the first valve does not satisfy the valve opening condition and is not opened. Conversely, if the suction pressure becomes lower than the lower reference value, it means that an abnormally low suction pressure state has occurred. In this case, the first valve satisfies the valve opening reference pressure and opens. Will be. As a result, the working fluid is discharged from the discharge section on the high pressure side to the drive chamber on the low pressure side via the first valve, the discharge capacity is reduced, the suction pressure is increased, and an abnormally low pressure state of the working fluid is avoided. Will be.

The reference valve opening pressure of the second valve during the operation of the cooling circuit is set higher than the upper limit reference value of the discharge pressure during the operation of the cooling circuit. That is, the discharge pressure does not always satisfy the valve opening reference pressure of the second valve during the operation of the cooling circuit, and the second valve is always closed during the operation of the cooling circuit. Therefore, the pressure increase in the drive chamber during the operation of the cooling circuit is performed only through the first valve.

The reference valve opening pressure of the first valve during the operation of the heating circuit is set lower than the lower limit reference value of the suction pressure of the working fluid during the operation of the heating circuit. Therefore, during operation of the heating circuit, the first valve is in principle closed. The reference valve opening pressure of the second valve is an upper limit reference value of the discharge pressure during the operation of the heating circuit. When the discharge pressure during the operation of the heating circuit is within the reference value, the second valve is closed. Is closed. On the other hand, when the discharge pressure of the working fluid reaches a predetermined high pressure state (abnormal high pressure state) during the operation of the heating circuit, both the first and second valves are opened.
Specifically, when the discharge pressure is in an abnormally high pressure state, the setting is changed so that the valve opening reference pressure of the first valve is increased, so that the first valve is opened. As a mode of the change, for example, the first
It is preferable to change the valve opening reference pressure of the valve to a value higher than the suction pressure when the discharge pressure is abnormally high. This is to ensure that the first valve is opened. Further, since the valve opening reference pressure of the second valve is set to the upper limit reference value of the discharge pressure at the time of operating the heating circuit, the discharge pressure under the abnormally high pressure state is actually higher than the upper limit reference value. When the discharge pressure becomes abnormally high, the second valve is opened. Therefore, when the discharge pressure of the working fluid becomes abnormally high during the operation of the heating circuit, both the first and second valves are opened. As a result, the working fluid is discharged from the discharge unit to the drive chamber via both the first and second volume changing means.
The discharge capacity is reduced and the discharge pressure is reduced quickly. Therefore, even if the discharge pressure suddenly rises in a short time, there is no possibility that the countermeasure against abnormal high pressure will be delayed.

In the air conditioner according to the sixth aspect, the valve opening reference pressure of the first and second valves in the air conditioner according to the fourth or fifth aspect is such that a solenoid provided for each valve is energized or de-energized. This will be changed as appropriate.

In the air conditioner according to claim 7, the second valve in the air conditioner according to claim 2 or 3 is configured to be opened by a differential pressure between the discharge pressure of the working fluid and a pressure other than the discharge pressure. ing. As the pressure other than the discharge pressure, for example, a pressure in a driving chamber, a suction pressure, an atmospheric pressure, a vacuum pressure, or the like can be adopted. In particular, it is preferable to use a pressure difference from the pressure inside the air conditioner because the device can be simplified. Specifically, the second valve is configured to be opened and closed by the differential pressure between the discharge pressure and the pressure in the drive chamber or by the differential pressure between the discharge pressure and the suction pressure. The pressure is preferably controlled by a differential pressure between the discharge pressure as the side pressure and the driving chamber pressure or the suction pressure as the low pressure side pressure.

According to an eighth aspect of the present invention, there is provided the air conditioner according to the seventh aspect, wherein a second path is provided in a path from the discharge section to the drive room.
A pilot valve is provided upstream of the valve body. This pilot valve is always closed when the cooling circuit is operating. That is, the working fluid is not sent to the second valve during the operation of the cooling circuit in order to prevent the second valve from inadvertently opening and interfering with the first capacity changing unit that is performing the capacity control. Is to do so. On the other hand, since the pilot valve is always open when the heating circuit operates, the working fluid is
And the second valve which is in charge of the capacity control when the heating circuit is activated.

According to a ninth aspect of the present invention, the pilot valve in the eighth aspect of the present invention is configured to open and close the pilot valve through energization or non-excitation of a solenoid, thereby realizing a timing for opening and closing the pilot valve and a reliable opening and closing operation. can do.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an air conditioner according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 2, the present air conditioner 100 is generally configured by a cooling circuit 151, a heating circuit 152, and a variable displacement compressor 101 which is a driving source of both circuits. Note that the capacity changing means, which is one of the components of the present invention, is not shown in FIG. 2 showing the general configuration of the air conditioner 100. The structure and operation of the capacity changing means will be described later in detail. This air conditioner 100
In the present embodiment, the air conditioner is configured as an in-vehicle air conditioner, and a drive shaft 125 of the variable displacement compressor 101 is connected to and driven by an engine 170 of the vehicle.

The cooling circuit 151 includes the variable displacement compressor 10
The first expansion valve 157 and the condenser 155 disposed on the path 151a from the discharge part D to the suction part S of the variable displacement compressor 101 operate by using the high-pressure working fluid compressed in Step 1. It has a heat exchanger 159 and an accumulator 161. Heat exchanger 159 is commonly referred to as an evaporator.

The heating circuit 152 includes the variable displacement compressor 10
It operates using the high-temperature and high-pressure working fluid compressed in step 1,
Second expansion valve 16 arranged on bypass passage 152a for guiding the working fluid discharged from discharge section D to heat exchanger 159
3, the heat exchanger 159, and the accumulator 161. That is, the heating circuit 152 is connected to the cooling circuit 151.
Is used as a part of the components. The heating circuit 152 having such a structure is commonly called a hot gas bypass heater.

The heat exchanger 159 is juxtaposed with the hot water heater 171. Cooling hot water from the engine 170 is circulated in the hot water heater 171 via a pipe 173.
In FIG. 2, a first on-off valve 153a and a second on-off valve 153b
Is a switching valve for selectively operating either the cooling circuit 151 or the heating circuit 152.

When the cooling circuit 151 operates, the working fluid which has been compressed by the variable capacity compressor 101 and has become high temperature and high pressure is sent to the condenser 155, where the heat of the high temperature working fluid is discarded to the outside. Liquefy. Next, the working fluid is decompressed by the first expansion valve 157 and
It is sent to 59, where it takes external heat and gasifies. The gasified working fluid is returned to the variable displacement compressor 101 via the accumulator 161 and is recirculated. When the heating circuit 152 operates, the variable displacement compressor 10
The working fluid that has been compressed at 1 and has become high temperature and high pressure is decompressed by the second expansion valve 163 and sent to the heat exchanger 159, where it releases heat to the outside. During the cycle of the heating circuit 152, the working fluid always circulates in a gaseous state through the heating circuit 152.

In the present embodiment, the heating circuit 152 is positioned as an auxiliary heating device. That is, the heat generated by the heat exchanger 159 during the operation of the heating circuit 152 is used as an auxiliary heating heat source for the hot water heater 171 described above. The heating circuit 152 is used, for example, at the time of starting the engine 170 or in a low-temperature environment such as when the outside air temperature is -20 ° C., for example, when the cooling water of the engine 170 does not have enough heat for heating.

Next, referring to FIG.
The structure of No. 1 will be described. A drive chamber 110 is formed inside the variable displacement compressor 101, and the drive chamber 1
The swash plate 130 is supported by the drive shaft 125 in the inside 10.
The swash plate 130 is supported by the drive shaft 125,
And rotates with the rotation of the drive shaft 125 in a state of being inclined with respect to. Further, the inclination angle of the swash plate 130 with respect to the drive shaft 125 is variable. Hereinafter, approaching a state orthogonal to the drive shaft 125 is referred to as “stand up of the swash plate 130”, and approaching horizontal in the illustrated state. "The swash plate 130 sleeps."

The swash plate 130 is connected at its peripheral edge to the head of the piston 135 via a movable shoe 131. A total of six pistons 135 are arranged around the drive shaft 125 (only one piston is shown in the figure), and are inserted into the six cylinder bores 109 so as to be slidable in the left-right direction in the figure. 6 cylinder bores 1
09 is fixed by a housing 101a of the variable displacement compressor 101 in the circumferential direction.

As shown, when the swash plate 130 tilts and rotates together with the drive shaft 125, the peripheral edge of the swash plate 130 slides relative to the fixed piston 135 in the circumferential direction. When the peripheral edge of the swash plate 130 inclined to the piston side is located corresponding to the piston 135 (FIG. 1 shows this state), the piston 135 is inserted deepest into the cylinder bore 109. When the peripheral edge of the swash plate 130 that is inclined most to the opposite side of the piston (the peripheral edge shown in the lower part of FIG. 3) is located corresponding to the piston 135 (the drive shaft 125 is rotated 180 degrees from the state of FIG. 3). (Corresponding to the case of rotation), the piston 135 is drawn out most from the cylinder bore 109. When the drive shaft 125 makes one rotation, each piston 135 makes one reciprocation in the left-right direction in each cylinder bore 109.

The bottom of each cylinder bore 109 has a suction hole 1
18a and a discharge hole 123a are provided, and the suction valve 118 corresponds to the suction hole 118a, and the discharge valve 123 corresponds to the discharge hole 123a. Each suction hole 118
a communicates with the suction chamber 115, and each discharge hole 123 a communicates with the discharge chamber 120. Piston 1 by swash plate 130
When 35 moves to the left in the figure, the working fluid is
16 to suction chamber 115, suction hole 118a, suction valve 118
Through the cylinder bore 109. Then
When the piston 135 moves rightward in the figure by the swash plate 130, the sucked working fluid is compressed to a high pressure state, and the discharge hole 123a, the discharge valve 123, the discharge chamber 120
Is discharged from the discharge port 121 via the

The displacement of the variable displacement compressor 101 is determined by the stroke of the piston 135. The stroke amount of the piston 135 is determined by the inclination angle of the swash plate 130. The more the swash plate 130 lies, the greater the stroke amount of the piston 135, and the larger the displacement of the variable displacement compressor 101. Conversely, the swash plate 130
, The stroke amount of the piston 135 becomes smaller, and the displacement of the variable displacement compressor 101 becomes smaller.

The inclination angle of the swash plate 130 is
, That is, the difference between the pressure in the drive chamber 110 and the pressure in the cylinder bore 109. In the present embodiment, the differential pressure is adjusted by increasing or decreasing the pressure in the drive chamber 110. When reducing the discharge capacity, the high-pressure working fluid in the discharge chamber 120 is supplied to the drive chamber 1
10 to increase the pressure in the drive chamber 110. Then, the swash plate 130 rises, the stroke amount of the piston 135 decreases, and the discharge capacity decreases. Conversely, when the capacity is to be increased, the working fluid in the discharge chamber 120 is prevented from being discharged to the drive chamber 110. Then, the swash plate 130 lies down, the stroke amount of the piston 135 increases, and the discharge capacity increases.

In this embodiment, as shown in FIG. 3, two capacity changing means are provided for discharging the high-pressure working fluid from the discharge chamber 120 to the drive chamber 110. One is a cooling capacity changing means 301 and the other is a heating capacity changing means 401. Cooling capacity change means 3
01 corresponds to the “first capacity changing means” in the present invention, and the heating capacity changing means 401 corresponds to the “second capacity changing means” in the present invention.

The cooling capacity changing means 301 generally includes a cooling capacity changing valve 303, a first cooling capacity changing passage 321 that connects the discharge chamber 120 and the cooling capacity changing valve 303, The cooling capacity changing valve 303 and the second cooling capacity changing passage 322 that connects the drive chamber 110 are provided. The heating capacity changing means 401 includes a heating capacity change valve 403, a first heating capacity change passage 421 that connects the discharge chamber 120 and the heating capacity change valve 403, and a heating capacity. A second heating capacity change passage 422 that connects the change valve 403 and the drive chamber 110 is provided. The drive chamber 110 and the suction chamber 115 are connected by a pressure reducing passage 501, and a throttle is provided on the pressure reducing passage 501 (not shown).

The first and second cooling capacity change passages 32
Numerals 1 and 322 are connected to a cooling capacity change valve 303, and both are brought into a state of communication or non-communication by a valve body 305. The valve body 305 is connected to a bellows 315 that controls opening and closing of the valve body 305 based on a suction pressure Ps detected through a suction pressure detection passage 313, and is connected to a plunger 307 of a solenoid 309 through a connection member 311. Are linked. The solenoid 309 is
Energized or de-energized by energizing the plunger 30
7 is energized. That is, the valve body 305
When s reaches a predetermined pressure, it is opened by the bellows 315, and the valve opening reference pressure can be changed by appropriately adjusting the urging force of the solenoid 309 on the plunger 307. The energization of the solenoid 309 is performed by a control means (not shown). The energization signal is supplied from the control means (which monitors a change in the discharge pressure Pd of the working fluid as described later). The valve reference pressure can be changed. Also,
The energization is cut off to eliminate the biasing force, and the bellows 31 is forcibly forced off.
5 can also open the valve.

The first heating capacity change passage 421 is provided with a first compartment 405 formed in the heating capacity change valve 403.
Connected to. Therefore, the pressure in the first compartment 405 is the discharge pressure Pd of the working fluid. The second heating capacity change passage 422 is connected to a second compartment 407 formed in the heating capacity change valve 403. Therefore, the second compartment 4
The pressure in 07 is the pressure Pc in the drive chamber 110. The first and second compartments 405 and 407 are brought into a state of communication or non-communication by the valve body 409. The valve body 409 is closed by a spring 409a in the valve closing direction (FIG. 3).
In the right direction), and the pressure (discharge pressure) Pd in the first compartment 405 is increased in the second compartment 40.
When the pressure becomes a predetermined value as compared with the pressure Pc in the driving chamber 7 (pressure in the driving chamber), the combined force of the pressure Pc in the second compartment 407 and the urging force of the spring 409a is overcome. (In FIG. 3, the valve element 409 moves to the left). Further, the valve body 409 is connected to the connecting member 411.
Through a plunger 413 of the solenoid 415. The solenoid 415 applies an urging force to the plunger 413 by excitation or non-excitation by energization. That is, the valve body 409 is connected to the discharge pressure Pd and the drive chamber 110.
The valve is configured as a differential pressure valve that is opened by a differential pressure with the internal pressure Pc.
Can be changed by appropriately adjusting the biasing force on the plunger 413. Alternatively, by cutting off the power supply to the solenoid 415, a high urging force is applied to the plunger 413 by the spring 409a so that the valve body 409 is always closed regardless of the magnitude of the discharge pressure Pd.

Next, the operation of the present air conditioner will be described.
As described above, when the cooling circuit 151 shown in FIG. 2 is operated, the working fluid that has been compressed by the variable capacity compressor 101 and has become high temperature and high pressure is supplied to the condenser 155 and the first expansion valve 1.
The refrigerant is returned to the variable capacity compressor 101 via the heat exchanger 57, the heat exchanger 159 and the accumulator 161, and is recirculated. When the heating circuit 152 is operating, the variable displacement compressor 10
The working fluid compressed to a high pressure in step 1
The refrigerant is returned to the variable displacement compressor 101 via the second expansion valve 163, the heat exchanger 159, and the accumulator 161 on the 52a and recirculated.

Regarding the control of the discharge capacity, first, the cooling circuit 15
1 (see FIG. 2) will be described. Cooling circuit 15
At the time of one operation, the capacity control is performed using the cooling capacity changing means 301 described above, and the heating capacity changing means 401 is not used. Therefore, the energization of the solenoid 309 is appropriately adjusted for the cooling capacity change valve 303, and the suction pressure P of the working fluid is adjusted.
The valve opening reference pressure of the valve body 305 is set so that the valve body 305 opens when s reaches a predetermined reference value. The reference value relating to the suction pressure Ps is set to the lower limit value of the suction pressure at which frost does not occur in the heat exchanger 159 (see FIG. 2). That is, when the suction pressure Ps falls below the allowable lower limit, it is determined that the suction pressure Ps has entered an abnormally low pressure state, and the cooling capacity changing means 30 is determined.
1 is started. on the other hand,
The heating capacity change valve 403 is always closed during the operation of the cooling circuit so that capacity control is not performed via the heating capacity change means 401. Specifically, the solenoid 415
Is appropriately adjusted, and the valve opening reference pressure of the heating capacity change valve 403 is set higher than the upper limit of the discharge pressure Pd of the working fluid during the operation of the cooling circuit. In other words, the discharge pressure Pd of the working fluid during the operation of the cooling circuit is always lower than the reference valve opening pressure.
03 is not satisfied, the heating capacity change valve 403
Is always closed during the operation of the cooling circuit. Alternatively, a high biasing force is applied to the plunger 413 by the spring 409a such that the valve 409 is always closed regardless of the magnitude of the discharge pressure Pd by cutting off the current supply to the solenoid 415.

During the operation of the cooling circuit, if the suction pressure Ps of the working fluid is not in the abnormally low pressure state, the cooling capacity change valve 3
Since the valve opening condition of 03 is not satisfied, the cooling capacity change valve 303 is closed. Of course, the discharge pressure of the working fluid during the operation of the cooling circuit does not satisfy the opening condition of the heating capacity change valve 403 (or the valve body 409 is forcibly closed by adjusting the energization to the solenoid 415). The heating capacity change valve 403 is closed. As a result, when the suction pressure Ps of the working fluid is not in the abnormally low pressure state, the working fluid is not discharged from the discharge chamber 120 to the drive chamber 110, and the capacity control is not performed.

On the other hand, if the suction pressure Ps of the working fluid becomes abnormally low during the operation of the cooling circuit, the opening condition of the cooling capacity change valve 303 is satisfied (the suction pressure Ps becomes a predetermined low pressure state). , The cooling capacity change valve 303 is opened. Of course, the discharge pressure of the working fluid during the operation of the cooling circuit does not satisfy the opening condition of the heating capacity change valve 403 (or the valve body 409 is forcibly closed by adjusting the energization to the solenoid 415). , Heating capacity change valve 40
3 is closed. As a result, the valve body 305 of the cooling capacity change valve 303 moves in the valve opening direction, and the first and second cooling capacity change passages 321 and 322 are communicated. Then, the working fluid is discharged from the high pressure side discharge chamber 120 to the drive chamber 110 via the first cooling capacity change passage 321, the cooling capacity change valve 303, and the second cooling capacity change path 322. Will be. As a result, "the pressure Pc in the drive chamber 110 increases", "the swash plate 130 stands up (the inclination angle of the swash plate 130 decreases)", "the stroke of the piston 135 decreases", and "the discharge capacity decreases". Through a series of actions, the suction pressure Ps of the working fluid increases, and the abnormally low suction pressure Ps state is suppressed. Although the drive chamber 110 communicates with the suction chamber 115 via the pressure reducing passage 501, the suction pressure P
The working fluid is prevented from escaping from the drive chamber 110 to the suction chamber 115 before the abnormal low pressure countermeasure in s is completed.

The working fluid in the drive chamber 110 is sent little by little to the suction chamber 115 via the decompression passage 501, and is sent again to the cylinder bore 109 to be compressed, and then to the cooling circuit again via the discharge chamber 120 and the discharge port 121. Will be discharged.

Next, the capacity control during the operation of the heating circuit 152 (see FIG. 2) will be described. When the heating circuit 152 is operating, a countermeasure against abnormally high discharge pressure is performed by using the cooling capacity changing means 301 together with the heating capacity changing means 401. First, regarding the heating capacity change valve 403, the energization to the solenoid 415 is appropriately adjusted, and the valve opening criterion of the valve 409 is opened so that the valve 409 is opened when the discharge pressure Pd of the working fluid reaches a predetermined reference value. Set pressure. Discharge pressure Pd
The reference value related to is set to the upper limit value of the discharge pressure so as not to apply an excessively high pressure to the heating circuit 152. That is, when the discharge pressure Pd exceeds the allowable upper limit, it is determined that the discharge pressure Pd has reached an abnormally high pressure state, and the heating capacity changing unit 40
1 is started. on the other hand,
The cooling capacity change valve 303 is configured to be closed when the discharge pressure Pd of the working fluid is not in the abnormally high pressure state during the heating circuit operation, and to be opened when the discharge pressure Pd is in the abnormally high pressure state. I do. Specifically, when the heating circuit is operated steadily (that is, when the discharge pressure of the working fluid changes below the upper limit allowable value during the operation of the heating circuit), the power supply to the solenoid 309 is appropriately adjusted. , Cooling capacity change valve 30
The valve opening reference pressure of No. 3 is set to the suction pressure P of the working fluid during the operation of the heating circuit.
It is set lower than the lower limit of s. As a result, during the steady operation of the heating circuit, the valve opening reference pressure of the cooling capacity change valve 303 is not satisfied, and the cooling capacity change valve 403 is closed. Alternatively, by energizing the solenoid 309, a high urging force is applied to the plunger 307 such that the valve body 305 is always closed regardless of the magnitude of the suction pressure Ps.

As for the heating capacity change valve 403,
When the heating circuit is operated steadily, that is, when the discharge pressure Pd of the working fluid is not in an abnormally high pressure state during the operation of the heating circuit, the opening condition of the heating capacity change valve 403 is not satisfied. The capacity change valve 403 is closed.
As a result, the discharge pressure P of the working fluid during the operation of the heating circuit
When d is not in an abnormally high pressure state, the working fluid is in the discharge chamber 1
No discharge from the drive chamber 110 to the drive chamber 110 is performed, and no capacity control is performed.

Next, a description will be given of the displacement control when the discharge pressure Pd of the working fluid becomes abnormally high during the operation of the heating circuit. First, as for the heating capacity change valve 403, the discharge pressure Pd of the working fluid becomes equal to or higher than the valve opening reference pressure and the valve opening condition is satisfied, and the heating capacity change valve 403 is opened. On the other hand, for the cooling capacity change valve 303, the valve opening reference pressure is changed by the following procedure. First, a control unit (not shown) monitors the transition of the discharge pressure Pd of the working fluid during the operation of the heating circuit.
Exceeds a predetermined upper limit reference pressure, the control unit issues a valve opening reference pressure change command signal to the cooling capacity change valve 303. As a result, the condition for energizing the solenoid 309 is changed, the urging force applied to the plunger 307 is changed as appropriate, and the valve opening set value of the valve body 305 is changed. When the heating circuit is operated constantly, the cooling capacity change valve 30
3 is the suction pressure P of the working fluid during the operation of the heating circuit.
Although it was set lower than the lower limit value of s, if the discharge pressure Pd is in an abnormally high pressure state, the valve opening reference pressure is increased to open the cooling capacity change valve 303. For example, the valve opening reference pressure is changed to a value exceeding the upper limit value of the working range of the working fluid suction pressure Ps during the heating circuit operation, or the energization of the solenoid is stopped to eliminate the urging force on the plunger 307, thereby reducing the suction pressure. The valve body 305 is forcibly opened regardless of the value of Ps.

When the discharge pressure Pd of the working fluid becomes abnormally high during the operation of the heating circuit through the above operation, both the cooling and heating capacity change valves 303 and 403 are opened, First and second cooling capacity change passages 32
1,322 and the first and second heating capacity change passages 42
The two discharge paths 1 and 422 are in communication with each other, and the working fluid is discharged from the discharge chamber 120 to the drive chamber 110 via the two discharge paths. As a result of the working fluid being discharged not only through the heating capacity change passage but also through the cooling capacity change passage, the discharge chamber 120
The amount of working fluid released per unit time to zero is greater than that discharged through only one path,
A boost within zero will be achieved quickly.

When both the cooling capacity change valve 303 and the heating capacity change valve 403 are opened, the working fluid is discharged from the discharge chamber 12.
0 to the driving room 110, the result is that “the driving room 110
The pressure Pc in the swash plate 130 rises "
0), the stroke of the piston 135 decreases, and the discharge capacity decreases, the discharge pressure Pd of the working fluid decreases, and the abnormally high discharge pressure Pd state is suppressed. Will be done. The driving room 110
Is communicated with the suction chamber 115 through the pressure reducing passage 501, but due to the restriction provided in the pressure reducing passage 501, the working fluid flows from the drive chamber 110 to the suction chamber 115 before the abnormally high pressure countermeasure of the discharge pressure Pd is completed. Is prevented from running away.

The working fluid in the driving chamber 110 is sent little by little to the suction chamber 115 via the decompression passage 501, and is sent again to the cylinder bore 109 to be compressed, and then to the heating circuit via the discharge chamber 120 and the discharge port 121. Will be discharged.

The cooling capacity changing means 301 and the heating capacity changing means 401 are independent of each other. Originally, the former is in charge of an abnormally low pressure of the working fluid suction pressure Ps during the operation of the cooling circuit. Is configured to take measures against abnormally high pressure of the discharge pressure of the working fluid at the time of operating the heating circuit.
In the present embodiment, the heating capacity change valve 4 is used as a countermeasure against abnormally high discharge pressure of the working fluid at the time of operating the heating circuit.
01 as well as the cooling capacity change valve 301, the working fluid is discharged from the discharge chamber 120 to the drive chamber 11 as quickly as possible.
It releases to zero.

According to the air conditioner according to the present embodiment, the working fluid once pressurized by the variable capacity compressor 101 is discharged to the drive chamber 110, so that the energy efficiency is somewhat deteriorated. The discharge capacity is reduced depending on the amount, the suction pressure is increased, and the discharge pressure is reduced. Since the working fluid is not thrown out of the heating circuit 152, no extreme energy loss occurs.
Further, a situation in which the working fluid for operating the heating circuit 152 runs short does not occur. That is, according to the present embodiment, in an air conditioner including a heating circuit that is a hot gas bypass heater, the working fluid in the heating circuit is discharged to the cooling circuit in order to suppress an abnormally high pressure state during the heating operation. In other words, there is no problem that the heating capacity is insufficient and that the working fluid which is caused to work by the compressor and is pressurized to a high pressure is wastefully discharged to the outside of the heating circuit, resulting in extremely low energy efficiency.

In addition, as a measure against abnormally high discharge pressure Pd,
Not only the heating capacity change valve 401 but also the cooling capacity change valve 3
01 is also used to connect the discharge chamber 120 and the drive chamber 110 via two paths.
The working fluid can be quickly released to the discharge pressure Pd, so that a countermeasure against abnormally high discharge pressure Pd can be taken reliably and quickly.

(First Modification of the Present Embodiment) FIG. 4 shows a first modification of the present embodiment. This is a modified example in which the configuration of the heating capacity changing unit 401 is different. As shown in FIG. 4, in the variable displacement compressor 701 according to the present modification, the heating displacement changing means 601 is used.
However, the pilot passage 621 (corresponding to the first heating capacity change passage 421 of the above embodiment),
It comprises a pilot valve 619, a heating capacity change valve 603, and a second heating capacity change passage 422.
The discharge chamber 120 is connected to the pilot valve 619 through the first pilot passage 621a. Pilot valve 6
Reference numeral 19 is connected to the first compartment 605 of the heating capacity change valve 603 through the second pilot passage 621b. The heating capacity change valve 603 further includes a second compartment 6
07 is formed, and the second compartment 607 is connected to the drive room 110 via the second heating capacity change passage 422. A valve body 609 is arranged between the first compartment 605 and the second compartment 607. The valve element 609 is usually
Valve closing direction by spring 609a (right direction in FIG. 4)
To the first and second compartments 605, 6
07 is in a non-communication state. The valve element 609 has a configuration as a differential pressure valve that is opened by a differential pressure between the pressure in the first compartment 605 and the pressure in the second compartment 607.
Normally, the pilot valve 619 is configured so that the first and second pilot passages 621a and 621b are not in communication with each other, and can move in the valve opening direction by energizing the solenoid 615. When moving in the valve opening direction, the first and second pilot passages 621a, 621
b is in a communication state.

Other structures, for example, the structure of the variable displacement compressor itself and the structure of the cooling capacity changing means 301 are the same as those of the above-described embodiment of the present invention, and the detailed description is omitted for convenience.

In the present modified example, during the operation of the cooling circuit, a measure for abnormally low suction pressure of the working fluid is taken only by the cooling capacity changing means 301, so that the heating capacity changing means 601 supplies the working fluid to the discharge chamber. 120 to drive room 110
Must not be released. In the case of the heating capacity change valve 403 in the above-described embodiment, in addition to the basic configuration as the differential pressure valve, the valve opening reference pressure can be appropriately changed by using the biasing force of the solenoid 415. Such a problem can be prevented. However, when the heating capacity change valve 601 is simply configured as a differential pressure valve that is opened and closed only by the differential pressure of two pressures as in the present modification, the differential pressure cannot be externally controlled, The heating capacity change valve 603 having the structure of the differential pressure valve may be opened carelessly during the operation of the cooling circuit, and may interfere with the capacity control by the cooling capacity change means 301. Therefore, during the operation of the cooling circuit, the pilot valve 61
9 is forcibly closed (the state shown in FIG. 4), and the pilot passage 621 is brought into a non-communication state. That is, during the operation of the cooling circuit, the pilot valve 619 is always closed to prevent the working fluid from being discharged from the discharge chamber 120 to the drive chamber 110 via the heating capacity changing means 601. The function of the cooling capacity changing means 301 during the operation of the cooling circuit is the same as that of the above-described embodiment, and a detailed description is omitted for convenience.

On the other hand, during the operation of the heating circuit, the working fluid is supplied from the discharge chamber 120 to the heating capacity changing valve 60 in order to take measures against abnormally high pressure of the working fluid by the heating capacity changing means 601.
It is necessary to open the pilot valve 619 so that it can be sent to 3. Therefore, the solenoid 615 is energized and excited to open the pilot valve 619. As a result, the pilot passage 621 is in a communicating state, and the working fluid is sent from the discharge chamber to the first compartment 605. As a result, the pressure in the first compartment 605 is set to the discharge pressure Pd,
It acts on the valve body 609 together with the pressure Pc in the drive chamber 110 guided into the second compartment 607 via the second heating capacity change passage 422.

If the discharge pressure Pd of the working fluid is not in the predetermined high pressure state during the operation of the heating circuit, that is, if it is not in the abnormally high pressure state, the discharge pressure Pd in the first compartment 605
Does not overcome the resultant force of the biasing force of the spring 609a in the valve closing direction and the pressure Pc in the second compartment 607, and the heating capacity change valve 603 is closed. Further, as in the above-described embodiment of the present invention, when the discharge pressure Pd of the working fluid is not at the predetermined high pressure state during the operation of the heating circuit, the cooling capacity change valve 303 is closed. Therefore, the working fluid is not discharged from the discharge chamber 120 to the drive chamber 110, and the capacity control is not performed.

When the discharge pressure Pd of the working fluid reaches a predetermined high pressure state during the operation of the heating circuit, that is, when the discharge pressure Pd reaches an abnormally high pressure state, the discharge pressure Pd in the first compartment 605 is increased by the spring 609a. Of the valve 6 against the resultant force of the urging force in the valve closing direction and the pressure Pc in the second compartment 607.
09 in the valve opening direction, and the heating capacity change valve 603 is opened. The control means (not shown) controls the discharge pressure Pd of the working fluid.
When the discharge pressure Pd exceeds the upper limit reference value, the energizing condition of the solenoid 309 is changed and the cooling capacity change valve 303 is opened. Cooling capacity change valve 303
Since a specific method for opening the valve is the same as that in the above-described embodiment, detailed description thereof will be omitted. When the discharge pressure Pd of the working fluid becomes abnormally high during the heating circuit operation, not only the heating capacity change valve 403 but also the cooling capacity change valve 3
As a result, the high-pressure working fluid in the discharge chamber 120 flows through the pilot passage 621-the heating capacity change valve 603-.
The drive room 11 via the second heating capacity change passage 422
0 and the first cooling capacity change passage 3
It is discharged to the drive room 110 via 21-cooling capacity change valve 303-second cooling capacity change passage 322. As a result of the pressure increase in the drive chamber 110 due to the release, a countermeasure against an abnormally high discharge pressure Pd is taken by the same operation as described in the above embodiment.

(Second Modification of the Present Embodiment) A second modification of the present embodiment is shown in FIG. This is a modification in which the structure of the heating capacity changing unit 601 is further changed from the first modification. In this modified example, the pilot valve arranged upstream of the heating capacity changing means configured as a differential pressure valve that does not perform external control is omitted. Although related to what has been described in the first modification, a differential pressure valve which is opened and closed simply by a differential pressure between the discharge pressure Pd of the working fluid and a pressure other than the discharge pressure Pd without performing external control is used for heating. When used for the capacity change valve 403, the following problems can be considered. During the operation of the cooling circuit, a countermeasure against abnormal low pressure of the suction pressure of the working fluid is taken only by the cooling capacity changing means 301.
Although it is necessary to close the cooling capacity change valve 603 so as not to release it from 0 to the drive chamber 110, since the opening condition of the heating capacity change valve 603 depends on the pressure difference between the two pressures and cannot be externally controlled, the cooling circuit There is a problem that the door may be opened carelessly during operation.

For this reason, in the first modification, the above problem is prevented by disposing the pilot valve 619 on the upstream side and forcibly closing the pilot valve 619. On the other hand, in the second modified example, the pilot valve 619 is omitted from the configuration of the first modified example. As a reason, if the heating capacity changing means is configured only with a simple differential pressure valve that cannot perform external control, and the differential pressure valve is opened during the operation of the cooling circuit,
The pressure in the drive chamber 110 is increased, and the discharge capacity is reduced. As a result, the discharge pressure Pd of the working fluid is reduced. Initially, the differential pressure valve is opened by the high discharge pressure Pd, but with such a decrease in the discharge pressure Pd, the valve is no longer maintained in the open state, and the differential pressure valve is eventually closed.
Actual failures are considered to be few. Therefore, the present inventors also propose a modification example in which the pilot valve is omitted and the heating capacity changing unit is configured with only a simple differential pressure valve that cannot perform external control.

As shown in FIG. 5, in the variable displacement compressor 800 according to this modification, the heating capacity changing means 801 includes a first heating capacity changing passage 821, a heating capacity changing valve 803, and a second heating capacity changing valve 803. The heating capacity change passage 422 of FIG. Again, the pilot valve is omitted. A first compartment 805 and a second compartment 807 are provided in the heating capacity change valve 803, and the first compartment 805 is connected to the discharge chamber 120 via the first heating capacity change passage 821. The second compartment 807 is in communication with the drive room 110 via the second heating capacity change passage 422. The detailed operation is the same as that of the first modified example described above, and the description is omitted for convenience. The cooling capacity changing means 301 and other configurations are the same as those in the above-described embodiment and the first modified example, and the detailed description is omitted.

In the present embodiment and each of the modifications, the cooling capacity changing means and the heating capacity changing means are both provided inside the variable capacity compressor. However, all or all of them are provided. A part may be provided outside the variable displacement compressor. Further, the number of pistons of the variable displacement compressor may be changed, or the pistons may be arranged on both sides of the swash plate instead of one side.

[0061]

The present invention is directed to an air conditioner disclosed in Japanese Patent Application Laid-Open No. 7-19630 by applying a discharge capacity control technique of a conventional variable displacement compressor to an air conditioner having a hot gas bypass heater circuit. The problem of the technology for countermeasures against abnormal high pressure in the device, that is, the problem that the working fluid in the hot gas bypass heater circuit is released to the cooling circuit and the heating capacity is insufficient, and the operation that the compressor works to increase the pressure to high pressure The problem of poor energy efficiency due to wasteful discharge of fluid out of the heating circuit is solved, and a conventional variable displacement compressor is added to an air conditioner equipped with a hot gas bypass heater circuit and a cooling circuit. There is a problem that may occur in the use of the hot gas bypass heater circuit. It was to be solved in conjunction with the problem that that.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing the structure of a conventional air conditioner.

FIG. 2 is a sectional view schematically showing a structure of an air conditioner according to the present embodiment.

FIG. 3 is a cross-sectional view illustrating a detailed structure of a variable displacement compressor and a capacity changing unit in the air conditioner according to the present embodiment.

FIG. 4 is a diagram showing a first modification according to the present embodiment.

FIG. 5 is a diagram showing a second modification according to the present embodiment.

[Explanation of symbols]

 101 Variable displacement compressor 110 Drive chamber 115 Suction chamber 120 Discharge chamber 125 Drive shaft 130 Swash plate 135 Piston 301 Cooling capacity changing means 303 Cooling capacity changing valve 321 First cooling capacity changing passage 322 Second cooling capacity Change passage 401 Heating capacity change means 403 Heating capacity change valve 405 First compartment 407 Second compartment 421 First heating capacity change passage 422 Second heating capacity change passage 619 Pilot valve 621 Pilot passage

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Naoya Yokomachi 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Tatsuya Koide 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture F term in Toyota Industries Corporation (reference) 3L092 AA02 AA05 AA11 BA05 BA08 BA27 DA01 DA03 EA03 EA05 FA23

Claims (9)

[Claims] 1. A compressor having a compressor, a cooling circuit, a heating circuit, and a capacity changing means, wherein the compressor has a suction part for sucking a working fluid, and a discharge part for discharging a compressed working fluid. A driving unit that is provided in the driving chamber and reduces the discharge capacity when the pressure in the driving chamber increases.The cooling circuit includes a capacitor disposed on a path from the discharge unit to the suction unit. A heat exchanger disposed downstream of the condenser, the heating circuit includes a bypass from the discharge section to the heat exchanger, and the heat exchanger; and the capacity changing unit includes: A first and a second capacity changing means for making the discharge unit and the driving chamber communicate with each other, wherein the first and the second capacity changing means communicate the discharging unit with the driving chamber; Being arranged in parallel in the passage, The first displacement changing means is provided when the suction pressure of the working fluid becomes a predetermined low pressure state during the operation of the cooling circuit, and when the discharge pressure of the working fluid becomes a predetermined high pressure state during the operation of the heating circuit. The discharge unit and the drive chamber are in communication with each other, and the second capacity changing unit is configured to, when the discharge pressure of the working fluid becomes the predetermined high pressure state during the heating circuit operation, cause the discharge unit and the drive chamber to communicate with each other. An air conditioner wherein the drive room is in communication. 2. The air-conditioning apparatus according to claim 1, wherein the first capacity changing unit is configured to operate when the suction pressure of the working fluid becomes a predetermined low pressure state during the operation of the cooling circuit and the heating circuit. A first valve that is opened when the discharge pressure of the working fluid reaches a predetermined high pressure state during operation, wherein the second capacity changing unit is configured to set the discharge pressure of the working fluid to the predetermined pressure during the heating circuit operation. An air conditioner having a second valve that opens when a high pressure state is reached. 3. The air conditioner according to claim 2, wherein the first valve and the second valve are provided in a housing of the compressor. 4. The air conditioner according to claim 2, wherein the first valve and the second valve have a variable valve opening reference pressure. . 5. The air conditioner according to claim 4, wherein the first valve opens when the suction pressure of the working fluid falls below a valve opening reference pressure, and the second valve opens the discharge pressure of the working fluid. When the cooling circuit operates, the valve opening reference pressure of the first valve is set to a lower reference value of the suction pressure of the working fluid during the cooling circuit operation. The reference valve opening pressure of the second valve is set to be higher than the upper limit reference value of the discharge pressure of the working fluid during the operation of the cooling circuit, and the reference valve opening pressure of the first valve is set to the heating circuit during the operation of the heating circuit. The first valve is opened so that the first valve is opened when the discharge pressure of the working fluid at the time of operating the heating circuit is set to a predetermined high pressure state while being set lower than the lower reference value of the suction pressure of the working fluid at the time of operation. The reference pressure is changed to a higher setting, and the opening of the second valve is changed. Reference pressure is the air conditioning apparatus characterized by being the upper limit reference value of the discharge pressure in the heating circuit operation. 6. The air conditioner according to claim 4 or 5, wherein the reference valve opening pressure of the first valve and the second valve is determined by energizing or deactivating a solenoid provided for each valve. An air conditioner characterized by being changed via excitation. 7. The air conditioner according to claim 2, wherein the second valve is opened by a differential pressure between a discharge pressure of a working fluid and a pressure other than the discharge pressure. An air conditioner characterized by the following. 8. The air conditioner according to claim 7, wherein said second displacement changing means is a pilot provided upstream of said second valve in a path from said discharge section to said drive chamber. An air conditioner, further comprising a valve, wherein the pilot valve is always closed when the cooling circuit is activated, and is always opened when the heating circuit is activated. 9. The air conditioner according to claim 8, wherein the pilot valve is opened and closed via energization or non-excitation of a solenoid.