DE102019126439A1 - Working equipment, in particular wheel loaders - Google Patents

Abstract

The invention relates to an implement, in particular a wheel loader, with a hydraulic circuit and a lifting frame with Z-kinematics. The lifting frame comprises a lifting arm, which can be pivoted about a horizontal pivot axis, and a deflection lever which is articulated to a connecting part and which is articulated to the lifting arm so as to be pivotable about a horizontal pivot axis. The lifting frame also includes an attachment to which an attachment can be reversibly mounted and which is articulated to the front end of the lifting arm spaced from the pivot axis and to the connecting part so as to be pivotable about two parallel pivot axes. The attachment has a hydraulic coupling part which can be automatically reversibly coupled by attaching an attachment to the attachment with an attachment-side hydraulic coupling part, thereby producing a hydraulic supply for the attachment. The hydraulic coupling part is connected to the hydraulic circuit via at least two hydraulic lines, the hydraulic lines being designed to be flexible, at least in sections. According to the invention, the hydraulic lines are attached to the reversing lever via a first suspension which is rotatably connected to the reversing lever about a horizontal axis of rotation.

Description

The present invention relates to an implement, in particular a wheel loader, according to the preamble of claim 1.

With many implements it is customary to use quick coupling systems for the quick and uncomplicated attachment of hydraulically operated implements, which are equipped with a hydraulic coupling through which a hydraulic connection can be automatically established between the hydraulic consumer or consumers of the attachment and the hydraulic system of the implement during attachment . Such a fully automatic hydraulic quick coupling system is for hydraulic excavators, for example in the EP 1 239 087 A1 disclosed.

Hydraulic couplings can also be used for work equipment with a lifting frame with Z-kinematics, as is often used in wheel loaders, in order to be able to attach a hydraulically operated work device or tool, such as a high-tip shovel, to the lifting frame quickly and easily.

An example of such a wheel loader 1 known from the prior art is shown in FIG 1 shown. The wheel loader 1 has a hydraulic circuit and a chassis 2 which, in this example, comprises a rear carriage and a front carriage connected to this via an articulated joint. A lifting frame 10 with Z-kinematics is attached to the front end of the vehicle, and a wheel loader shovel 60 is pivotably mounted at its front end. The lifting frame 10 comprises a lifting arm 12, which can be pivoted by means of two hydraulic lifting cylinders 5 and is H-shaped in plan view, with a cross tube 18 forming the H-web. A deflection lever 14 is articulated on the lifting arm 12 and can be pivoted by means of a hydraulic tilting cylinder 6. The deflection lever 14 is articulated to a connecting part 16 (also called a connecting strap) at the front end (ie, facing away from the chassis). The lifting frame 10 further comprises an attachment frame 20, on which an attachment 60 (in this example the wheel loader shovel 60) can be reversibly mounted. The scaffolding 20 is articulated to the front end of the lifting arm 12 and to the end of the connecting part 16 facing away from the deflecting arm 14 about two parallel horizontal axes and can be pivoted by pivoting the deflecting lever 14 relative to the lifting arm 12 by means of the tilting cylinder 6. A hydraulic coupling for producing a hydraulic supply to the attachment 60 can be arranged on the attachment frame 20. The scaffolding can also be a quick coupler.

This special kinematics and the movement paths of the individual components that result when the mast moves have an effect on the hydraulic lines to be laid from the hydraulic circuit of the implement to the front attachment or a hydraulic coupling located there, and therefore represent a challenge for the integration of a fully automatic hydraulic coupling device. In particular, due to the large angular ranges of the reversing lever and the scaffolding that can be traversed, sufficiently long hydraulic lines must be available.

The hydraulic lines are typically brought up to the front end of the lifting arm or to the connecting strap by means of fixed suspensions or fastenings along the lifting arm and / or the reversing lever, since the latter is pivoted to a lesser extent than the scaffolding. This makes additional hydraulic hoses and connections necessary so that the hydraulic lines can be brought up to and connected to the attachment in a segmented manner, which increases the costs, the maintenance effort and the risk of leaks.

In addition, the hydraulic hoses must be made long enough so that sufficient hose length is available even in extreme positions of the lifting frame, in particular when the attachment frame or attachment is pivoted completely in and out. This results in hose bulges in less extreme positions that can protrude into the work area and require additional, complex protective measures such as steel hose coils. The hoses' necessarily exposed position in such a case also reduces their service life. The use of pivotable hydraulic connections such as swivel screw connections on the hydraulic coupling is also disadvantageous, since this increases the costs, the maintenance effort and the risk of leaks.

Against this background, the present invention is based on the object of providing an implement with a lifting frame with Z-kinematics, which enables a fast and fully automatic hydraulic connection of an attachment to the hydraulic circuit of the implement. The hydraulic line system of the working device required for this should be constructed simply and inexpensively and should be characterized by a low risk of leakage.

According to the invention, this object is achieved by a working device with the features of claim 1. Accordingly, the working device according to the invention, which is in particular a wheel loader, a hydraulic circuit and a mast with Z-kinematics. The lifting frame comprises a lifting arm, which can be pivoted about a horizontal pivot axis, and a deflection lever which is articulated to a connecting part and which is articulated to the lifting arm so as to be pivotable about a horizontal pivot axis. The lifting arm can preferably be pivoted by means of at least one lifting cylinder and the deflection lever by means of at least one tilting cylinder.

The lifting frame also includes an attachment to which an attachment can be reversibly mounted and which is articulated to the front end of the lifting arm spaced from the pivot axis and to the connecting part so as to be pivotable about two parallel pivot axes. The attachment has a hydraulic coupling part which can be automatically reversibly coupled by attaching an attachment to the attachment with an attachment-side hydraulic coupling part, thereby producing a hydraulic supply for the attachment. The hydraulic coupling part is connected to the hydraulic circuit of the working device via at least two hydraulic lines, the hydraulic lines being designed to be flexible, at least in sections.

According to the invention, the hydraulic lines are attached to the reversing lever via a first suspension which is rotatably connected to the reversing lever about a horizontal axis of rotation.

Due to the rotatable mounting of the first suspension on the reversing lever, the hydraulic lines can be optimally aligned in every position of the mast. As a result, there is no need to provide excessive hydraulic line lengths, which in certain positions can lead to bulges that are disruptive or even protrude into the work area. Instead, the entire lift and tilt area can be passed through without protruding or highly tensile hydraulic lines, which protects the hydraulic lines and extends their service life.

Furthermore, the rotatable first suspension according to the invention enables a direct connection of several hydraulic lines to a fully automatic hydraulic quick coupling, in the present case to the hydraulic coupling part, which considerably simplifies and accelerates the attachment process of the attachment. Because one of the suspensions of the hydraulic lines is designed to be rotatable, the hydraulic lines can be connected to the hydraulic coupling part via fixed connections, which is more cost-effective and less prone to leakage than pivotable hydraulic connections such as rotary screw connections. The rotatability of the first suspension, on the other hand, does not affect the hydraulic lines fastened in it or through it or connected to it, since there is no movement of individual hydraulic line sections relative to one another, but a movement or alignment of the hydraulic lines relative to the lifting frame.

In addition, the flexible hydraulic guide according to the invention is independent of the specific quick-release or hydraulic coupling system used, since only the hydraulic connections on the coupling side may need to be adapted. Furthermore, the implement according to the invention manages with fewer hydraulic line suspensions or fastenings, which reduces the costs and the maintenance effort. Finally, the hydraulic line guide according to the invention is also suitable for large line or hose diameters, since sharp bends are avoided and the hydraulic lines automatically adapt to the position of the mast.

Advantageous embodiments of the invention emerge from the subclaims and the following description.

The hydraulic coupling parts preferably form a hydraulic coupling, as shown in FIG EP 1 239 087 A1 is revealed.

In one embodiment it is provided that the lifting arm is H-shaped in plan view and has a cross tube forming the H web, the deflection lever preferably being articulated like a rocker to a cheek formed on the cross tube.

In a further embodiment it is provided that the first suspension is arranged in the area of the pivot axis of the reversing lever, the axis of rotation preferably coinciding with the pivot axis of the reversing lever. In the latter case, the first suspension can be mounted on the deflection pin, which forms the pivot axis of the deflection lever, the first suspension being rotatable relative to the deflection pin. By placing the first suspension in the area of the deflection bolt, the hydraulic lines can optimally adapt to the movement of the mast, while the attachment point formed by the first suspension is ideally located between the hydraulic coupling part and other possible fixed attachment points of the hydraulic lines on the lift arm in the direction of its pivot axis. In particular, half the length of the reversing lever in both directions can be regarded as the “area” in the context of this invention. An area within a few centimeters, eg 10-15 cm, around the deflection bolt can also be regarded as an “area”. But it is also conceivable that there are mast geometries are, in which an attachment of the first suspension at another point of the reversing lever is advantageous, for example outside of the previously defined area.

In a further embodiment it is provided that the hydraulic coupling part has fixed or fixed hydraulic connections to which the hydraulic lines are connected, the hydraulic connections assuming a predetermined angle with respect to the hydraulic coupling part. Such fixed hydraulic connections are stable and inexpensive and can be used here due to the adaptability of the alignment of the hydraulic hoses by means of the first suspension, whereby the fixed hydraulic connections can have a certain degree of flexibility or tolerances, for example through the use of spring elements. The angle of the hydraulic connections to the rear surface of the hydraulic coupling part or to the plane running through the pivot axes of the scaffolding is preferably 90 °, but can also have other values and a certain tolerance of a few degrees, for example. This can also depend on the exact geometry of the mast.

In a further embodiment it is provided that the hydraulic lines are fastened to the lifting arm via a second suspension which is firmly connected to the lifting arm, the second suspension preferably being fastened or mounted on the cross tube. Alternatively, the second suspension can also be arranged on the inside of the outer struts of the H-shaped lifting arm. The fixed second suspension is easy and inexpensive to implement, for example as a simple hose clamp or pipeline. The adaptability of the hydraulic lines to the position of the mast is already ensured by the rotatable first suspension.

In a further embodiment it is provided that the hydraulic lines between the hydraulic coupling part and the second suspension are connected to the mast only by means of the first suspension, with preferably no further movable, ie in particular rotatable, suspensions for fastening the hydraulic lines on the mast apart from the first suspension are provided. The first suspension is sufficient to ensure that the alignment of the hydraulic lines can be optimally adjusted. This means that further fastenings or suspensions for the hydraulic lines can be dispensed with, which reduces the costs and complexity of the hydraulic line routing.

In a further embodiment it is provided that the first suspension forms a mounting angle with the vertical which remains essentially constant when the deflection lever or the attachment scaffold is moved and the lifting arm is stationary at the same time. The mounting angle is defined here in particular by the angle between the vertical and that plane which contains the axis of rotation of the first suspension and runs vertically through the hydraulic lines at the point that is closest to the axis of rotation. This level is referred to below as the “first auxiliary level”.

The mounting angle depends on the position of the lift arm and the length of the hydraulic lines. In a configuration in which a first line section or hydraulic hose is used between the hydraulic coupling part and the first suspension per hydraulic line and a second line section or hydraulic hose is used between the first and second suspension, which are connected to one another via corresponding hydraulic connections of the first suspension, the mounting angle depends on the respective lengths of the pipe sections or hydraulic hoses. In a configuration in which continuous hydraulic lines are used, which are only held or clamped by the first suspension, the mounting angle depends on the lengths of the line sections on both sides of the first suspension. The mounting bracket can thus be optimally adapted to the geometry of the mast by selecting the lengths of the line sections or hydraulic hoses accordingly. This gives the hydraulic line guide according to the invention a high degree of flexibility.

It is also possible to configure the hydraulic lines, i.e., as described above, in particular the lengths of the line pieces or hydraulic hoses, in which the angle of the previously defined first auxiliary plane to the longitudinal axis of the lifting arm, also referred to as the relative mounting angle, for any movement of the lifting frame, that is, the lifting arm and / or the reversing lever, remains essentially constant. The relative mounting angle can be between 10 and 80 °, preferably between 30 and 60 °. In the case of a non-linear geometry of the lifting arm, its longitudinal axis can be defined differently to determine the relative mounting angle. For example, the longitudinal axis of the lifting arm can be defined as the line lying in a plan view centrally between the side struts of the lifting arm and running within the plane that intersects the pivoting axis of the lifting arm and the lower pivoting axis of the scaffolding. Depending on the configuration / geometry of the lift arm, other definitions can also be useful here.

The above term “essentially constant” means that the Mounting angle (or the relative mounting angle) is of course not completely fixed, but is subject to a certain fluctuation or variation depending on the position of the lifting frame, which, however, is significantly less than the entire angular range of the reversing lever or scaffolding. In addition, the mounting angle set for a specific lifting arm position and for a specific selection of the lengths of the hydraulic hoses and / or arrangements of the suspensions can also vary slightly due to certain tolerances, for example material and / or manufacturing tolerances.

In a further embodiment it is provided that the variation of the mounting angle with a movement of the reversing lever or scaffolding and at the same time stationary lifting arm is less than 20 °, preferably less than 10 °, and particularly preferably less than 5 °. In a particularly preferred exemplary embodiment, the variation is less than 3 °. These values can also apply to the previously defined relative mounting angle. A variation of more than 10 ° can occur in particular when the first suspension is arranged outside the reversing lever, that is, when the axis of rotation of the first suspension does not coincide with the pivot axis of the reversing lever.

In a further embodiment it is provided that the hydraulic lines comprise flexible hoses which are arranged between hydraulic connections and / or hydraulic connections. In the context of the present invention, the combinations of hydraulic hoses, connections and connections can then be referred to as hydraulic lines. The hydraulic lines can be designed overall (that is to say especially in the area between the hydraulic coupling part and the second suspension) as continuous hydraulic hoses which are connected to hydraulic connections of the hydraulic coupling part. Alternatively, the hydraulic lines per line can be composed of several hose pieces, which are connected to one another, for example, by hydraulic connections. Bulkhead screw connections can be used for this.

In a further embodiment it is provided that the first suspension has hydraulic connections, the hydraulic lines between the hydraulic coupling part and the first suspension being designed as flexible hydraulic hoses and being connected to the hydraulic connections. The hydraulic connections themselves are firmly attached to the first suspension and have first connections which preferably extend in the direction of the hydraulic coupling part. The latter feature means in particular that the first connections of the hydraulic connections, when considering a plane that intersects the longitudinal axis of the lifting arm perpendicularly and contains the axis of rotation of the first suspension (hereinafter referred to as "second auxiliary plane"), point to that side of this plane, on which the hydraulic coupling part is located.

In a further embodiment it is provided that the hydraulic lines between the first and the second suspension are designed as flexible hydraulic hoses and are connected to the hydraulic connections. For this purpose, the hydraulic connections have second connections, which preferably extend in the direction of the second suspension. This in turn means that the second connections point to that side of the second auxiliary plane on which the second suspension is located.

In a configuration in which the hydraulic lines between the hydraulic coupling part and the second suspension are designed as continuous hydraulic hoses, the hydraulic connections are preferably hose feedthroughs, whereby the end regions of the hose feedthroughs on both sides can be viewed as connections in the sense described above. In a configuration in which the hydraulic lines between the hydraulic coupling part and the first suspension on the one hand and between the first and second suspension on the other hand are designed as separate hydraulic hose pieces, the hydraulic connections have actual connections on both sides of the first suspension to which the hydraulic hose pieces are connected. These are preferably bulkhead screw connections. However, it is also conceivable that a combination of hydraulic connection with actual connections and hose clamps can be used, for example with several different hydraulic lines.

In both cases, the second suspension can comprise a hose clamp or be designed as such, which represents a particularly simple design. Alternatively or additionally, hydraulic connections with connections to which the hydraulic hoses are connected can also be used here.

In a further embodiment it is provided that the hydraulic connections pointing in the direction of the hydraulic coupling part and / or the second suspension are angled, in particular are angled downwards in the direction of the lifting arm, so that the hydraulic hoses are independent of the movement of the lifting frame at a predetermined angle with the first Suspension are connected. In particular, it is the previously described connections of the hydraulic connections that are angled. But you can also do this accordingly angled hose feed-throughs are used. As a result, the end regions of the hydraulic hoses adjoining the connections always assume a certain angle to the first auxiliary plane, which angle corresponds to the angle of the connections of the hydraulic connections. The angle can be 45 °, for example.

The angled hydraulic connections ensure that when the mast moves, no uncontrolled bulges of the hydraulic hoses can arise, in particular in the area between the hydraulic coupling part and the first suspension. If the angle is not specified by the hydraulic connections, an uncontrollable and irreversible bulging of the hydraulic hoses can occur in this area, especially near the first suspension. Such an undesired change of direction can occur spontaneously or, for example, be caused by a pressure surge in a hydraulic line. This can damage the hydraulic hoses, for example through contact with nearby components, and cause chafing and kinks.

In a further embodiment it is provided that the hydraulic hoses in the area of the hydraulic connections of the first suspension have a curvature with a constant sign regardless of the movement of the mast. In particular, the hydraulic hoses in the area of the first suspension have a bulge pointing downwards or towards the lifting arm, which points in the same direction regardless of the movement of the lifting frame and thus always a rectified (i.e. negative or positive - depending on the definition or viewing direction) Has curvature, the amount of which, however, depends on the position of the mast. “Curvature” means, in particular, the mathematical curvature in a side view of the working device or the hydraulic hoses.

In contrast, the hydraulic hoses in the area of the hydraulic connections of the hydraulic coupling part preferably have a curvature, the sign of which varies with the movement of the mast. This means that the hydraulic hoses, depending on the position, in particular of the scaffolding, bend away from the hydraulic connection of the hydraulic coupling part upwards or downwards. For example, the hydraulic hoses curve downward in the case of an attached wheel loader shovel inclined downwards and upward in the direction of the first suspension with a wheel loader shovel pivoted upward. As a result, the spatial routing of the hydraulic hoses is always defined and there are no unwanted changes in direction.

In a further embodiment it is provided that the hydraulic lines in the area between the hydraulic coupling part and the first suspension are located above a lower edge of the working device, regardless of the position of the lifting frame. The lower edge is in particular the lower edge of the attachment scaffolding, which can also be a lower edge of an attachment. This ensures that the hydraulic lines never touch the ground or protrude into the working area of the implement and can thus be damaged. The smallest distance between the hydraulic lines and the floor, which is also referred to as slack, is the smallest in particular with a lowered lifting arm and a tipped-in scaffold or attachment. The sag is preferably greater than 5 cm, particularly preferably greater than 10 cm, in order to have a sufficient safety distance from the floor.

In a further embodiment it is provided that the attachment has two hydraulic coupling parts, which can be automatically reversibly coupled by attaching an attachment to the attachment with two attachment-side hydraulic coupling parts, thereby producing a hydraulic supply for the attachment. A hydraulic supply by means of two hydraulic coupling parts can be advantageous, for example, in the case of an attachment with several hydraulic consumers, such as a high-tip shovel with a hydraulic hold-down device. Each hydraulic coupling part is connected via at least two hydraulic lines to a separate or a common hydraulic circuit of the implement in order to supply the different consumers of the attachment. When the hydraulic coupling parts are connected to a common hydraulic circuit, the supply of the individual consumers can be controlled via hydraulic valves in the hydraulic circuit.

A separate first suspension and a separate second suspension are preferably provided for each hydraulic coupling part, which are arranged in particular in a plan view of the lifting frame on opposite sides of the longitudinal axis of the lifting arm, i.e. to the right and left of it but at the same height. It can be provided that the axes of rotation of the two first suspensions coincide and furthermore preferably coincide with the pivot axis of the reversing lever.

All of the embodiments described above apply to such an arrangement of a plurality of hydraulic coupling parts, each with a plurality of first and possibly second suspensions. With each of the hydraulic coupling parts, a different number of hydraulic lines with possibly different shapes or Diameters and possibly different material properties such as stiffnesses. For example, one of the hydraulic coupling parts can be connected to two and the other of the hydraulic coupling parts to three hydraulic lines. In the latter case, the three hydraulic lines are held by the associated first and the associated second suspension. Each of the hydraulic couplings is preferably formed by a hydraulic coupling block, as shown in FIG EP 1 239 087 A1 is revealed.

In a further embodiment it is provided that the swivel axes of the scaffold simultaneously represent the locking axes for locking the add-on device, i.e. the add-on device is connected to the scaffold and locked via the swivel axes. This results in a connection between the attachment and scaffolding without a front dimension or mounting height, which increases the maximum load capacity of the implement. In particular, the scaffolding is a quick coupler without front dimensions, i.e. without mounting height. The combination of quick coupler without front dimensions and fully automatic hydraulic quick coupling is only made possible or significantly facilitated by the flexible hydraulic line routing according to the invention.

• 1: ein Beispiel eines aus dem Stand der Technik bekannten Radladers in einer perspektivischen Ansicht;
• 2: das Hubgerüst des erfindungsgemäßen Arbeitsgeräts gemäß einem Ausführungsbeispiel in einer ersten Stellung in einer schematischen Seitenansicht;
• 3: das Hubgerüst gemäß 2 in einer zweiten Stellung;
• 4: das Hubgerüst gemäß 2 in einer dritten Stellung;
• 5: eine schematische Visualisierung des Montagewinkels und der Varianz des Montagewinkels;
• 6: den Umlenkhebel samt erster Aufhängung des erfindungsgemäßen Arbeitsgeräts gemäß einem Ausführungsbeispiel in einer perspektivischen Explosionsansicht;
• 7: das Hubgerüst des erfindungsgemäßen Arbeitsgeräts gemäß einem Ausführungsbeispiel in einer seitlichen Querschnittsansicht;
• 8: das Hubgerüst gemäß 7 in einer Draufsicht;
• 9: eine Vergrößerung der Hydraulikkupplung des Ausführungsbeispiels gemäß 7 in einer seitlichen Querschnittsansicht;
• 10: das Hubgerüst gemäß 7 in einer weiteren Stellung mit aufgerichtetem Hubarm; und
• 11: das Hubgerüst gemäß 7 in einer weiteren Stellung mit abgesenktem Hubarm.

Further features, details and advantages of the invention emerge from the exemplary embodiments explained with reference to the figures. Show it:

• 1 : an example of a wheel loader known from the prior art in a perspective view;
• 2 : the mast of the working device according to the invention according to an embodiment in a first position in a schematic side view;
• 3 : the mast according to 2 in a second position;
• 4th : the mast according to 2 in a third position;
• 5 : a schematic visualization of the mounting angle and the variance of the mounting angle;
• 6th : the reversing lever together with the first suspension of the implement according to the invention according to an embodiment in a perspective exploded view;
• 7th : the mast of the working device according to the invention according to an embodiment in a lateral cross-sectional view;
• 8th : the mast according to 7th in a plan view;
• 9 : an enlargement of the hydraulic coupling of the embodiment according to FIG 7th in a side cross-sectional view;
• 10 : the mast according to 7th in another position with the lift arm raised; and
• 11 : the mast according to 7th in another position with the lift arm lowered.

The 1 shows a wheel loader 1 known from the prior art with a lifting frame in Z-kinematics according to the preamble of claim 1, the hydraulic coupling and the hydraulic lines not being shown here. The 1 was already described at the beginning, so that a repetitive description can be dispensed with at this point. The exemplary embodiments of the implement according to the invention described below are based on a wheel loader 1, as shown in FIG 1 is shown. However, it can also be any other work device with a lifting frame in Z-kinematics.

The 2-4 show schematic side views of the front part of the implement according to the invention 1 as longitudinal sections through the mast 10 in three different positions of the mast 10 . The means of the lifting cylinder 5 (not shown here) pivotable lifting arm 12th is on the front end of the implement 1 around a horizontal pivot axis A. pivotably articulated. The reversing lever 14th is to one on the cross tube 18th trained cheek 19th around a horizontal pivot axis B. pivotably articulated. The scaffolding 20th is at both the front end of the lift arm 12th around a horizontal pivot axis C. as well as at the front end of the connecting part 16 around a horizontal pivot axis D. pivotably articulated. The swivel axes A. , B. , C. and D. as well as the cross tube 18th run parallel to each other. With the reference number 4th is one of the front wheels of the implement 1 designated. By actuating the tilt cylinder 6th becomes the reversing lever 14th around the pivot axis B. pivoted, which in turn due to the coupling through the connecting part 16 the scaffolding 20th and thus also the attachment 60 around the pivot axis C. is pivoted or tilted.

The scaffolding 20th is designed as a quick coupling part of a quick change device, by means of which an attachment 60 (in the present embodiment a wheel loader shovel) can be mounted reversibly quickly and easily. This is on the attachment 60 a quick coupling part on the attachment side is mounted, which is connected to the quick coupling part or scaffolding on the implement side 20th is engageable and lockable. The quick coupling part or scaffolding 20th has no front dimensions or no mounting height, whereby the swivel axes C. and D. at the same time for fastening and locking the attachment tool 60 serve. In contrast, a quick coupler with a mounting height or front dimension would mean that the swivel axes C. and D. of the scaffolding 20th and the locking axes on which the attachment tool 60 can be fastened, fall apart, that is, are spaced apart. However, this results in a larger lever arm, which has a negative impact on the maximum load capacity of the implement 10 affects.

To help you assemble the attachment 60 quick and easy hydraulic supply to the attachment 60 to be able to produce (for example when using a high-tip shovel as an attachment 60 ), is on the scaffolding 20th a hydraulic coupling part 22nd arranged, which during the assembly of the attachment 60 with a corresponding hydraulic coupling part on the attachment side 21 cooperates. This is when attaching the attachment 60 a hydraulic connection established fully automatically. The hydraulic coupling part is for this purpose 22nd via several hydraulic lines 50 with the hydraulic circuit of the implement 1 connected.

The hydraulic coupling part 22nd has hydraulic connections for this 24 on which flexible first hydraulic hoses 52 are connected. The hydraulic connections 24 are fixed to the hydraulic coupling part 22nd connected and take to its rear wall or to one through the pivot axes C. and D. extending plane a fixed angle of, for example, 90 °. The first hydraulic hoses 52 are at the other end via a first suspension 30th on the reversing lever 14th attached to achieve flexible and defined hose routing.

In particular, the two hydraulic coupling parts or halves 21, 22 couple out of a circular movement due to a corresponding circular movement when the attachment is connected 60 to the scaffolding or the quick coupler 20th . This is the case, for example, with a hydraulic coupling, such as that shown in FIG EP 1 239 087 A1 is described. In such a case, it can be advantageous with regard to the coupling that occurs from a circular movement if the fixed hydraulic connections 24 have a certain angular tolerance, for example 90 ° ± a few degrees. This can be done, for example, with flexible elements such as springs. As an alternative or in addition, it can be provided that after the end of the circular movement in the coupling, the two hydraulic coupling parts 21 , 22nd are brought together linearly, for example by means of an actuator.

The first suspension 30th is around an axis of rotation E. rotatable on the reversing lever 14th stored, the axis of rotation E. with the pivot axis B. coincides. For this is the first suspension 30th on the pivot axis B. forming reversing pin of the reversing lever 14th attached and freely rotatable relative to this (see 6th ). The first suspension 30th has hydraulic connections 32 , 34 on that are on both sides of the in the 2-4 drawn first auxiliary level H extend. The one on the side of the hydraulic coupling part 22nd arranged sections of the hydraulic connections are designated by 32 and the sections arranged on the other side by 34. In this embodiment the hydraulic connections are 32 , 34 designed as bulkhead fittings and therefore have on each side of the plane H connections 32 , 34 on. The first hydraulic hoses 52 are to the connections 32 the hydraulic connections 32 , 34 connected.

To the opposite connections 34 the hydraulic connections 32 , 34 are second flexible hydraulic hoses 54 connected, which up to a second suspension 40 run over which the second hydraulic hoses 54 firmly to the lift arm 12th are connected. The second suspension 40 is fixed, ie immobile on the outside of the cross tube 18th of the lift arm 12th mounted, in this embodiment in the upper part of the pivot axis A. facing area of the cross tube 18th . Starting from the second suspension 40 are the hydraulic lines 50 to not specified here and in the 2-4 with the hydraulic circuit of the implement indicated by means of two parallel lines 1 connected. About the placement of the second suspension 40 can (apart from the hose lengths used) in particular the courses of the first and second hydraulic hoses 52 , 54 as well as the position, ie in particular the mounting bracket, of the first suspension 30th influence. In other words, the second hydraulic hoses hold 54 the first suspension 30th or the first hydraulic hoses 52 in the desired position.

The connections of the hydraulic connections 32 , 34 , ie the protruding ends of the bulkhead screw connections are opposite the first auxiliary level H (i.e. in the 2-4 down towards the lift arm 12th ) angled, for example by 45 °. This will determine the direction in which the hydraulic hoses 52 , 54 in the area of the first suspension 30th run, predetermined so that there are no unwanted or uncontrolled bulges or evertings of the hydraulic hoses 52 , 54 , especially the first hydraulic hoses 52 , can come. Such an unwanted and potentially irreversible eversion 53 of the first hydraulic hoses 52 is in the 4th shown. Alternatively, the hydraulic connections 32 , 34 straight and the ends or connections of the hydraulic hoses 52 , 54 be angled.

Due to the free rotation of the first suspension 30th , the fixed hydraulic connections 24 at the Hydraulic coupling part 22nd , the angled design of the hydraulic connections 32 , 34 as well as the one on the cross tube 18th fixed second suspension 40 a flexible hydraulic hose guide is created that enables multiple hydraulic lines 50 to connect to a fully automatic hydraulic coupling, to reduce the number of fastenings required, to provide a defined and therefore gentle hose routing and to get by without moving hydraulic couplings or connections or swivel screw connections that are at risk of leaks. Depending on the position or movement of the mast 10 the freely rotatable first suspension aligns itself 30th automatically so that there is always enough hose length available without kinks or excessively small radii of curvature in the hydraulic hoses 52 , 54 comes. In addition, the controlled movement of the hydraulic hose gives the operator a better view of the working area of the implement 1 as the hydraulic lines 50 do not protrude so much into the work area.

To illustrate this flexible adaptability of the hydraulic guide according to the invention, they show 2-4 the mast 10 in three different positions in which the lift arm 12th remains in a lowered position and the scaffolding 20th or attachment 60 by pivoting the reversing lever 14th is tilted into different positions. As can be seen, the angle of the first auxiliary plane remains H relative to the vertical V , which can also be used as a mounting bracket α is referred to, essentially the same. The rotation of the bell crank 14th is therefore due to the rotatably mounted first suspension 30th balanced.

The mounting bracket α depends on the lift / tilt position of the lift arm 12th as well as the hose lengths of the hydraulic hoses 52 and 54 and adjusts itself for a certain position of the lift arm 12th depending on the selected hose lengths to a certain value α a. This results in a certain tolerance in the selected length of the first hydraulic hoses 52 , which in the 4th is denoted by the reference symbol x. This tolerance can be approx. 20% of the hose length of the first hydraulic hoses 52 be. In addition, the length of the second hydraulic hose 54 can be varied. By varying the lengths of the first and / or second hydraulic hoses 52 , 54 the mounting bracket a can be flexibly adapted to the circumstances.

During operation, ie when the mast moves 10 , the mounting angle a varies only a few degrees, as in the 5 is illustrated. Here is the compared to the total movable angular range of the scaffolding 20th or reversing lever 14th very small variation Δα of the mounting angle a, which can only be a few degrees (for example approx. 5 ° or 3 °) when the scaffolding is pivoted 20th shown. Reasons for the variation Δα can also be fluctuating material parameters (diameter, stiffness, etc.) as well as hose lengths. In particular, the mounting bracket a points at the tilting-in and tilting-out end positions of the attachment 60 or scaffolding 20th the greatest deviations.

During the mounting bracket a only with respect to a certain position of the lifting arm 12th (such as the one in the 2-4 shown lowered position) remains essentially constant, changes the above-described relative mounting angle, which with respect to the lifting arm 12th , d .H. whose longitudinal axis is defined, essentially not independent of the lifting arm position.

As a result of the hydraulic hose routing according to the invention, the sign of the curvature of the first hydraulic hoses remains 52 in the area of hydraulic connections 32 the first suspension 30th constant. So is in the 2-4 to see that the first hydraulic hoses 52 in every position to the left in the direction of the scaffolding 20th bend. In contrast, the sign of the curvature changes in the area of the fixed hydraulic connections 24 on the hydraulic coupling part 22nd . In the 2 and 3 the first hydraulic hoses bend 52 to the left or up towards the lower edge of the lift arm 12th while in the 4th , in which the wheel loader bucket 60 is fully dumped, to the right toward the top of the lift arm 12th bend. The first hydraulic hoses run in this position 52 S-shaped, so they change the sign of curvature. In the positions of 2 and 3 the sign of the curvature remains the same.

The optimized hose routing also prevents the hydraulic hoses 52 in a lowered position of the mast 10 touch the ground. This is particularly the case when the attachment tips over 60 with the lift arm lowered 12th problematic. This position is in the 3 shown. As can be seen, there is minimal slack due to the flexible hose routing d (ie safety distance to the ground). That slack d is preferably at least 8-10 cm. Preferably there is a variance of approx. 20% of the hose length of the first hydraulic hoses 52 to an equal slack d .

It can be provided that in addition to the first and the second suspension 30th , 40 no further fastening of the hydraulic lines 50 on the mast 10 is located. Alternatively, a further fixed attachment of the hydraulic lines can be used 50 between the second suspension 40 and the chassis 2 on the lift arm 12th be arranged, in particular on an inside of the H-shaped lifting arm 12th . The second hydraulic hoses can be used for this 54 extend up to this further fastening, whereby they extend from the second suspension, which is designed, for example, as a hose clamp 40 be held and fixed.

Instead of separate, ie separate, first and second hydraulic hoses 52 , 54 to be provided, which via angled bulkhead screw connections 32 , 34 are connected to one another, continuous hydraulic hoses can also be used, with the hydraulic connections 32 , 34 are then preferably designed as angled hose ducts or holders. This also allows the necessary direction to be specified for the continuous hydraulic hoses.

In the 6th is an embodiment of the first suspension 30th Shown as an exploded view showing the hydraulic connections 32 , 34 are formed by bulkhead screw connections, which in one opposite the reversing lever 14th rotatably mounted retaining plate 36 are attached. In the embodiment shown here, the bulkhead screw connections are not 32 , 34 but the ends of the hydraulic hoses (not shown) 52 , 54 angled. The bulkhead fittings are accordingly 32 , 34 just trained here.

The attachment of the retaining plate 36 takes place here by means of a screw connection in the center of the lever bolt, which is the pivot axis B. of the reversing lever 14th forms. The central element is a screw connection or screw 38 , which are then provided with a washer or washer on an outer screw head and by one on the retaining plate 36 attached bracket 37 is passed through. The holding plate 34 is provided with several (here two) through-holes into which the bulkhead screw connections 32 , 34 are screwed in or framed. The number of bulkhead fittings 32 , 34 depends on the number of hydraulic lines to be attached 50 . At the protruding ends of the bulkhead screw connections 32 , 34 the hydraulic hoses, which are angled at the ends, in particular 52 , 54 screwed on. The screw connection 38 is fixed to the reversing bolt, with the reversing lever 14th another mother 39 the screw connection 38 countered and another washer or washer is attached. Thus, the bracket 37 due to the arrangement of the shims on both sides and the locked screw connection opposite the reversing lever 14th or deflection bolts remain movable.

The 7-8 show the mast 10 and the hydraulic hose guide according to the invention based on a specific exemplary embodiment, wherein the 8th a top view of the lift arm 12th and the 7th a side view along the in the 8th with a2 designated section shows. The hydraulic lines 50 between the second suspension 40 and the hydraulic circuit of the implement 1 are not shown for reasons of clarity.

Only a single hydraulic coupling or hydraulic coupling part has been mentioned above 22nd and the hydraulic lines connected to it 50 (to which the corresponding hydraulic connections 24 , Hydraulic connections 32 , 34 and hydraulic hoses 52 , 54 count). As in particular in the 8th can be seen, this hydraulic arrangement can be on one side of the bell crank 14th be arranged (in the 8th is this from the cab 3 seen from the left side). It can of course be on the other side (i.e. in the 8th the right side) a second hydraulic coupling with corresponding hydraulic lines 50 be provided. The number and material properties (such as diameter, rigidity, etc.) of the hydraulic lines 50 the second hydraulic coupling can be different from those of the first hydraulic lines 50 be. The first and second suspensions 30th , 40 are in this case preferably on the opposite side of the reversing lever 14th arranged, so mirror-symmetrical to the longitudinal axis of the mast 10 or lifting arm 12th or reversing lever 14th . Both hydraulic coupling parts 22nd can be connected to a separate or a shared hydraulic circuit of the implement 1 be connected. This can be done, for example, with an attachment 60 can be used with several hydraulic consumers (such as a high-tip shovel with hydraulic hold-down device). As hydraulic lines 50 can be connected to the first hydraulic coupling part 22nd for example an inlet and a return and to the second hydraulic coupling part 22nd an inlet, a return and a leakage oil line must be connected. However, other arrangements are also conceivable in which more than two hydraulic couplings and corresponding hydraulic lines 50 and suspensions 30th , 40 come into use.

In the 9 is finally the area marked with the reference symbol a1 7th shown enlarged, which the connected hydraulic coupling with the implement-side and attachment-side hydraulic coupling parts 21 , 22nd shows. It can be seen that the hydraulic clutch in this exemplary embodiment is a suspension 23 as well as a linear guide, so that a precisely fitting, fault-free and leak-free, fully automatic coupling of the hydraulic coupling halves 21 , 22nd is guaranteed when the quick coupling parts are brought together. Regarding the details of this hydraulic coupling is explicitly referred to the disclosure of EP 1 239 087 A1 referenced.

In the 10 and 11 is that already in 7th illustrated mast 10 shown in two different positions, both in the position of the reversing lever 14th as well as in the position of the lift arm 12th distinguish. In the 10 is the lift arm 12th in a raised position with the lifting cylinder extended 5 and retracted tilt cylinder 6th so that the wheel loader bucket 60 is pivoted down. In the 11 is the lift arm 12th however, by retracting the lifting cylinder 5 fully lowered while the tilt cylinder 6th is extended so that the wheel loader bucket 60 is pivoted upwards.

The respective auxiliary level is in both figures H drawn in, their angle to the vertical V (not shown here) the mounting bracket α defined for the respective mast position. As previously described, the mounting bracket remains α for a certain (held) position of the lift arm 12th when the reversing lever moves 14th essentially constant. However, the mounting angle changes α with one movement of the lift arm 12th so that there are different positions of the lift arm 12th different mounting angles α surrender.

This results in the mast 10 a maximum angular range that the mounting bracket α when the mast moves 10 can drive through. This angle range is determined by the minimum and maximum mounting angles amin and α _max in the extreme positions of the mast 10 defined and depends on the geometry of the mast 10 and the hydraulic hose suspension, so in particular the positions of the first and second suspension 30th , 40 and / or the lengths of the first and second hydraulic hoses used 52 , 54 , from. The amount of this angular range lα _max - α _min | can for example be between 80 ° and 120 ° or between 90 ° and 110 °. Within this angular range there is in turn that for a certain fixed position of the lifting arm 12th a mounting bracket α adjusts the movement of only the reversing lever 14th remains essentially constant, that is to say varies in particular by only a few degrees Δα.

In the 10 and 11 it can be seen that the angle between the first auxiliary plane H and the longitudinal axis of the lift arm 12th (not shown), the so-called relative mounting angle, is essentially constant for both mast positions. The longitudinal axis of the non-linear lifting arm can be defined as the line that passes through the pivot axes A. and C. runs and seen from above in the middle between the side struts of the lift arm 12th runs.

In the 10 and 11 is also easy to see that the curvature of the first hydraulic hoses 52 in the area of the fixed hydraulic connections 24 Depending on the mast position, the sign changes (in the 10 are the first hydraulic hoses 52 down and in the 11 upwards from the fixed hydraulic connections 24 curved away), while the sign of the hose curvature in the area of the first suspension 30th remains the same (in both figures the first hydraulic hoses bend 52 to the left of the first suspension 30th path). It can also be seen that in the 11 The extreme mast position shown with the wheel loader shovel pivoted upwards 60 and lift arm fully lowered 12th the first hydraulic hoses 52 not over the lower edge of the wheel loader bucket 60 protrude into the work area.

List of reference symbols

1

Working device

2

Vehicle frame

3

Driver's cab

4th

wheel

5

Lifting cylinder

6th

Tilt cylinder

10

Mast

12th

Lift arm

14th

Reversing lever

16

Connecting part

18th

Cross tube

19th

cheek

20th

Scaffolding

21

Hydraulic coupling part (on the attachment side)

22nd

Hydraulic coupling part (on the implement side)

23

feather

24

Hydraulic connections

30th

First suspension

32

Hydraulic connection

34

Hydraulic connection

36

Retaining plate

37

bracket

38

Screw connection / screw

39

mother

40

Second suspension

50

Hydraulic lines

52

First hydraulic hoses

53

Uncontrolled bulging of the first hydraulic hoses

54

Second hydraulic hoses

60

Attachment

A.

Swivel axis lift arm

B.

Swivel axis pivot lever

C.

Swivel axis attachment scaffold

d

Slack

D.

Swivel axis attachment scaffold

E.

Axis of rotation first suspension

H

First auxiliary level

V

vertical

α

Mounting bracket

αmin

Minimal mounting angle

αmax

Maximum mounting angle

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 1239087 A1 [0002, 0016, 0039, 0047, 0064]

Claims (16)

Work device (1), in particular a wheel loader, with a hydraulic circuit and a lifting frame (10) with Z-kinematics, the lifting frame (10) having a lifting arm (12) that can be pivoted about a horizontal pivot axis (A) and one on the lifting arm (12) a horizontal pivot axis (B) pivotably articulated deflection lever (14) which is articulated to a connecting part (16), and an attachment frame (20) to which an attachment (60) can be reversibly mounted and which is connected to that of the pivot axis (A) spaced front end of the lifting arm (12) and is articulated to the connecting part (16) pivotably about two parallel pivot axes (C, D), wherein the scaffold (20) has a hydraulic coupling part (22), which by adding an attachment (60 ) to the scaffolding (20) with an attachment-side hydraulic coupling part (21) automatically reversible and thereby a hydraulic supply of the attachment (60) can be produced, and the hydraulic coupling part (22) via whom at least two at least partially flexible hydraulic lines (50) are connected to the hydraulic circuit, characterized in that the hydraulic lines (50) on the reversing lever (14) via a first suspension (30) rotatably connected to the reversing lever (14) about a horizontal axis of rotation (E) ) are attached. Tool (1) after Claim 1 , characterized in that the lifting arm (12) is H-shaped and has a cross tube (18) forming the H web, the deflection lever (14) preferably being hinged to a rocker-like cheek formed on the cross tube (14). Tool (1) after Claim 1 or 2 , characterized in that the first suspension (30) is arranged in the area of the pivot axis (B) of the reversing lever (14), the rotation axis (E) preferably coinciding with the pivot axis (B) of the reversing lever (14). Work device (1) according to one of the preceding claims, characterized in that the hydraulic coupling part (22) has fixed hydraulic connections (24) to which the hydraulic lines (50) are connected, the hydraulic connections (24) at a predetermined angle in relation to the hydraulic coupling part ( 22), the angle preferably being 90 °. Work device (1) according to one of the preceding claims, characterized in that the hydraulic lines (50) are attached to the lifting arm (12) via a second suspension (40) firmly connected to the lifting arm (12), the second suspension (40) preferably is attached to the cross tube (18). Tool (1) after Claim 5 , characterized in that the hydraulic lines (50) between the hydraulic coupling part (22) and the second suspension (40) are only connected to the mast (10) by means of the first suspension (30), preferably on the mast (10) apart from the first suspension (30) no further movable suspensions for fastening the hydraulic lines (50) are provided. Tool (1) according to one of the preceding claims, characterized in that the first suspension (30) forms a mounting angle (a) with the vertical which remains essentially constant when the reversing lever (14) is moved and the lifting arm (12) is stationary at the same time . Tool (1) after Claim 7 , characterized in that the variation of the mounting angle (a) when the reversing lever (14) is moved and the lifting arm (12) is stationary at the same time is less than 20 °, preferably less than 10 °, and particularly preferably less than 5 °. Work device (1) according to one of the preceding claims, characterized in that the hydraulic lines (50) comprise flexible hydraulic hoses (52, 54) which are arranged between hydraulic connections (24) and / or hydraulic connections (32, 34). Tool (1) after Claim 9 , characterized in that the first suspension (30) has hydraulic connections (32, 34), the hydraulic lines (50) between the hydraulic coupling part (22) and the first suspension (30) being designed as flexible hydraulic hoses (52) and connected to the hydraulic connections ( 32) are connected, the hydraulic connections (32) preferably being hose ducts or bulkhead screw connections. Implement (1) according to the Claims 5 and 10 , characterized in that the hydraulic lines (50) between the first and second suspension (30, 40) are designed as flexible hydraulic hoses (54) and are connected to the hydraulic connections (34), the second suspension (40) preferably comprising a hose clamp . Tool (1) after Claim 10 or 11 , characterized in that the hydraulic connections (32, 34) pointing in the direction of the hydraulic coupling part (22) and / or the second suspension (40) are angled, in particular are angled in the direction of the lifting arm (12), so that the hydraulic hoses (52, 54 ) are connected to the first suspension (30) independently of the movement of the mast (10) at a predetermined angle. Implement (1) according to one of the Claims 10 to 12th , characterized in that the hydraulic hoses (52) in the area of the hydraulic connections (32) of the first suspension (30) have a curvature with a constant sign regardless of the movement of the lifting frame (10), the hydraulic hoses (52) in the area of the hydraulic connections ( 24) of the hydraulic coupling part (22) preferably have a curvature, the sign of which varies with the movement of the lifting frame (10). Work device (1) according to one of the preceding claims, characterized in that the hydraulic lines (50) in the area between the hydraulic coupling part (22) and the first suspension (30) are above a lower edge of the work device (1) regardless of the position of the mast (10) , wherein the lower edge of the implement (1) is in particular the lower edge of the scaffolding (20) or an attachment (60). Work device (1) according to one of the preceding claims, characterized in that the attachment (20) has two hydraulic coupling parts (22) which can be automatically reversibly coupled by attaching an attachment (60) to the attachment (20) with two hydraulic coupling parts (21) on the attachment and thereby a hydraulic supply of the attachment (60) can be produced, with each hydraulic coupling part (22) being connected via at least two hydraulic lines (50) to a separate or a common hydraulic circuit, with preferably a separate first suspension (30) for each hydraulic coupling part (22) and a separate second suspension (40) is provided, which is arranged in particular in a plan view of the lifting frame (10) on opposite sides of the longitudinal axis of the lifting arm. Work device (1) according to one of the preceding claims, characterized in that the pivot axes (C, D) of the attachment scaffold (20) simultaneously represent the locking axes for locking the attachment (60), wherein the attachment (20) is in particular a quick coupler without front dimensions .

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