EP3399106A1 - Quick swap coupling for fixing an attachment - Google Patents

Abstract

The invention relates to a quick-change coupling (11) for fastening an attachment to an excavator arm with a receiving and fastening device (13), a fixed first insertion opening (16) which is formed or fixed to a first end of the receiving and fastening device (13) , and a movable closing element (19) arranged on the receiving and fastening device (13) and having a second insertion opening which can be moved from an open position in which an attachment can be coupled or uncoupled to a closing position in which the Holding bolts of the implement through the insertion openings (16) are engaged and clamped. The closing element (19) is biased in the open position and lockable.

Description

The invention relates to a quick-change coupling for attaching an attachment to an excavator arm according to the preamble of claim 1 and a method for biasing and relaxing a closing element of a quick-change coupling according to the preamble of claim 15.

State of the art

Quick-change couplings are known from the prior art, which allow the quick attachment, detachment and replacement of an attachment to an arm of an excavator. For example, an excavator bucket having a certain width can be quickly exchanged for another bucket having a larger or smaller width on the excavator arm.

All existing quick-change couplings have a sliding closure hook or a sliding closure element. The locking hook comprises one of the two retaining bolts of the attachment in a closed position when the attachment is coupled to the excavator arm. If the attachment is to be disconnected, the locking hook is moved to an open position.

For fully automatic quick-change couplings, the locking hook is driven by means of an actuator. The actuator can be operated pneumatically, hydraulically or electrically. This allows the attachment to be coupled to and uncoupled from the excavator arm without the operator having to get out of the cab. The actuator can be controlled via a control provided in the cab. These fully automatic quick couplings are characterized by a high ease of use, but are relatively expensive to purchase.

Mechanical quick-change couplings must be operated directly manually. The operator must therefore manually connect to the uncoupling and uncoupling the hook in the open position or in the closed position and lock the locking hook in the closed position. The mechanical quick-change couplings are cheaper to purchase than those described in the last paragraph Quick-change couplings. In addition, the maintenance and installation costs are lower. However, the attachment and disconnection of an attachment is tedious and therefore time consuming.

In the EP 2 055 842 A2 is a semi-automatic coupling for an excavator bucket on an excavator described. On a rotating body, a 5-step hole is provided. A sled can be moved by springs. Together with the carriage, two coupling pins and a pin are moved. The pin can lock in the 5 paragraphs and thereby secure the coupling pins in different extended positions. The rotary body is biased by a spring means and fixedly connected to a cam. If the bucket is hung with the bolt in the claw, so presses a retaining means of the bucket on a release pin. The trigger pin releases the rotating body from the biased position, causing the carriage to disengage and the coupling pins to fix the bucket to the coupling. With a removable tool, a pivot pin is rotated, which is firmly connected to the cam and the rotary body. By turning the rotary body of the bolt is linearly displaced and biased in the open position of the coupling. A metered relaxation of the carriage when no bucket is coupled to the coupling, is not possible or only with great effort and risk.

In the GB 2 412 361 A is also described a semi-automatic coupling in which a closure element is biased by a spring. A retaining element with a release element holds the closure element in the open pretensioned position. A retaining bolt of a bucket presses the release element and thereby the closure element is released and closes the clutch without securing against accidental opening. The coupling is clamped with a manually operated lever.

The WO 94/25689 describes a coupling for fixing an attachment to an excavator arm, which is hydraulically or manually operated. A base joint directs a closure part, through which closure part the coupling can be opened and closed. The base joint includes an intermediate arm, a projecting arm and an activation arm. The intermediate arm, which is pivotally connected to the other arms and the closure part, is designed as a pressure cylinder. The impression cylinder comprises a cylinder rod and a compression spring. In the Closure position, the closure part is biased by the pressure cylinder and the base joint is in a dead center position in which it can not be pressed. On the projecting arm, a handle is arranged, with which the base joint is rotatable about an axis of rotation and thereby the closure part between the closed position and the open position is manually displaceable. A hydraulic activation cylinder is articulated on the activation arm, by means of which the base joint can likewise be rotated and the closure part can be opened and closed from the driver's cab.

Object of the invention

From the disadvantages of the described prior art, the object initiating the present invention results in the further development of a generic mechanical quick-change coupling in that the coupling of an attachment is simplified and at the same time the operating safety is improved.

description

According to the prior art, a quick-change coupling for attaching an attachment to an excavator arm comprises a receiving and fastening device and a fixed first insertion opening which is formed or fixed to a first end of the receiving and fastening device. Further, the quick-change coupling comprises a arranged on the receiving and fastening device, movable closing element with a second insertion opening, which can be moved from an open position in which an attachment can be coupled or disconnected, in a closed position in which the retaining bolts of the attachment through the insertion openings are engaged and clamped.

The closing element is biased in the open position and lockable. The closing element does not have to be moved manually from the open position to the closed position, but moves automatically by relaxing the preload in the closed position as soon as the closing element is unlocked. The present quick-change coupling is therefore semiautomatic, resulting in a simplification of the operation and leading to a quick coupling process of an implement. Furthermore, the quick-change coupling is free of hydraulic or pneumatic actuators, making the quick-change coupling is particularly reliable and low maintenance.

The solution of the problem is achieved in a quick-change coupling in that on the receiving and fastening device, a control lever is movably arranged, which has formed a first hand approach, whereby he is operable with the first hand of the user of the clutch and which operating lever, the closing element in the Open and locked in the closed position and unlocked and that the clutch comprises a clamping lever with a second hand approach, whereby the clamping lever with the second hand of the user is operated simultaneously with the operating lever for biasing and relaxing the closing element. Since the user of the clutch must use both hands to move the closing element in the open position and bias, the clutch is particularly safe and injury in the operation of the clutch, especially hand injuries are excluded. Since both hands are inevitably used in safe places of the clutch, no hand can be in a place where it could be injured.

In the context of this patent application is to be understood by a hand approach, an area on the operating lever and the clamping lever, which allows the operation of the operating lever and the clamping lever with one of the hands or one or more fingers of the user. Such a hand attachment can therefore be a handle or a hook. It is also conceivable that the hand attachment is an extension of the lever or the lever has an area which can be attacked by the user so that the operating lever or the clamping lever can be moved in a direction provided.

The operating lever makes it possible to secure the closing element in the open and in the closed position. As a result, the quick-change coupling is reliably protected against malfunctions, which can lead to accidents in the worst case. The unlocking of the closing element is done by manual intervention or by further displacement from the open position with the help of the second retaining bolt or a clamping lever. Since other forms of unlocking are not possible, the quick-change coupling works very easily and safely.

In a particularly preferred embodiment of the invention, the operating lever between a first position in which the operating lever locks the closing element in the closed position, a second position in which the closing element between the closing position and the oven position is movable and a third position in which the operating lever, the closing element locked in the open position, movable. The closing element can only be moved to the open position when the operating lever is in the second position. The pivoting in the second position can only be done by a conscious manual intervention. In addition, a spring element presses the closing element in the closed position. The closing element is therefore double-protected against accidental opening in a surprisingly simple manner. Unintentional release of the attachment from the quick-change coupling is reliably excluded.

As it has proven expedient if the operating lever between the receiving and fastening device and the closing element is arranged and is rotatably hinged to the receiving and fastening device. The control lever is accordingly well protected against dirt and mechanical damage. The twisting of the operating lever up to a stop is intuitive to implement. Accordingly simple and error-prone is the operation of the operating lever.

In a further particularly preferred embodiment of the invention, a sliding guide is provided on the operating lever, which cooperates with a guide element arranged on the closing element, which engages in the slotted guide. Both the control lever and the closing element are positively guided and the mobility of the operating lever and the closing element are interdependent. As a result, the closing element can only be transferred from the closed position into the open position if the operating staff moves the operating lever and the tensioning lever successively and in a coordinated manner. The quick-change coupling is repeatedly protected against malfunction by simple mechanical means.

Conveniently, the guide element in the slide guide can be locked when the operating lever is in the third position. The biased in the open position closing element can not press the operating lever from the third position to the second position, since the guide element, preferably a pin, is pressed into a recess of the slide guide by the bias. The locking can be only cancel when a specific operation is performed. Preferably, the unlocking of the operating lever is canceled in the third position when the closing element is moved beyond the open position out against the closing position. This shift can be done by the second retaining bolt or the clamping lever. Accidental opening of the closing element can be reliably prevented by providing the specially shaped link guide in a surprisingly simple manner.

The invention is also preferably characterized in that the slotted guide is essentially a Z-shaped recess. The specially shaped recess allows the operating lever to move from the first position to the second position during manual pivoting. Only after moving the closing element in the open position, the operating lever can be further pivoted to the third position. The inevitably stepwise to be carried over transfer of the closing element from the closed position to the open position can be achieved by simple mechanical means and at the same time leads to a particularly safe quick-change coupling.

In a further particularly preferred embodiment of the invention, the operating lever is biased in the third position. This makes it possible that the operating lever can pivot from the third position automatically in the second and first position and releases the closing element after its release in the third position. The closing element can therefore automatically slide from the open position into the closed position. Another advantage of operating lever preload is that manual operation of the control lever must be deliberate against resistance.

Conveniently, the operating lever is pivotally connected to a first end of a rod and a second end of the rod is passed through a arranged on the receiving device transverse web. The pole fulfills two tasks in a surprisingly simple way. After being biased, it pushes the operating lever from the third position to the second and first position. It also fulfills a control function, as it visualizes in which position the closing element is located. If the closing element is in the open position, the second end of the bar protrudes from the crossbar and is visible. In the closing position of the closing element, the second end of the rod is withdrawn and invisible. Carry the second end a signal color, so it is also recognizable from the cab of the excavator when it protrudes from the crossbar.

Preferably, the first end of the rod is circular in shape and is received in a formed on the operating lever Gelenkpan. This form of joint connection is particularly low. Additional holding means can be dispensed with, since the joint connection is limited by a plate of the receiving device and the closing element. The distance between the plate and the closing element is determined by the height of the operating lever and is not increased by the articulated connection between the rod and the operating lever.

The bias of the rod is preferably achieved in that on the rod, a spring is plugged, which is compressible between a projection provided on the rod and the cross bar.

In a further preferred embodiment of the invention, the clamping lever is removable from the coupling and on the receiving and fastening device, a passage opening is provided, in which a clamping lever for moving the closing element from the closed position into the open position against the bias is suspended. The shorter end of the L-shaped clamping lever protrudes through the passage opening and can move the closing element in the open position. Preferably retaining grooves are provided on the longitudinal sides of the passage opening, which receive a transverse axis of the clamping lever and on which the transverse axis can rotate and support.

In a further particularly preferred embodiment of the invention, the closing element is displaceable beyond the open position counter to the direction of the closing position, whereby the operating lever can move automatically from the third position to the second position. This form of unlocking the closing element leads to a surprisingly simple way to automatically connect an attachment to the quick-change coupling. If the excavator arm is positioned such that the attachment rotates about the first retaining bolt in the direction of the quick-change coupling, the second retaining bolt presses the closing element in the direction described above. As a result, the closing element is unlocked. The operating lever is automatically pressed into the first position and the closing element automatically in the Closing position pressed, since both the operating lever and the closing element are biased. The closing element engages the second retaining pin, whereby the attachment is coupled to the quick-change coupling.

Conveniently, a through-opening is provided on the receiving and fastening device, through which the operating lever between the first, the second and the third position is movable. The access opening is preferably provided on a plate on which the operating lever is attached. The plate projects beyond the control lever, which protects it, in particular from being bent or broken off.

It proves to be advantageous if the closing element is preloaded with a spring element in the open position. The spring element automatically moves the closing element into the closed position when the closing element is released from the operating lever. In the closed position, the closing element is held by the spring element and is additionally locked by the operating lever in the first position. It can also be provided several spring elements. Suitable are coil springs, gas springs or other elastic springs.

Conveniently, the spring element is connected to the closing element and the crosspiece. The cross bar provides sufficient space and stability, so that the spring element can support.

Another aspect of the invention relates to a method for biasing and relaxing a closure member of a quick-change coupling as described above. A user of the clutch moves with his first hand a cocking lever, whereby the closing element is moved from a closed position to an open position, in which open position, the closing element is biased and locked.

According to the invention, the user operates simultaneously with his second hand a movable on the clutch operating lever, the operating lever releases the movement of the closing element in the open position by its corresponding movement and by further movement of the operating lever, the closing element is locked in the open position. This procedure ensures that the user of the coupling must place both hands in safe positions. It is therefore impossible that the user injured during the operation of the clutch on the hands. In a further particularly preferred embodiment of the invention, the closing element is moved from the open position to the closed position on the one hand by an attachment, which is coupled to the clutch, the locking of the operating lever by moving the closing element opens and on the other hand, the user of the coupling the clamping lever with its first Hand operated and the operating lever simultaneously operated with his second hand, whereby the closing element is moved in doses from the open position to the closed position.

The coupling allows the closing element to be released if the clutch is not in operation for a longer period. The manually performed relaxation process of the closing element can be dosed, since the user can counteract with the tensioning lever abrupt relaxation after loosening the lock. The lifting of the locking of the closing element in the preloaded open position is canceled by appropriate rotation of the operating lever.

Figur 1:

eine Draufsicht auf eine halbautomatische Schnellwechselkupplung zum Befestigen eines Anbaugeräts an einem Baggerarm mit einem Schliesselement in einer Schliessposition und einem Bedienhebel in einer ersten Position;

Figur 2:

eine Seitenansicht der Schnellwechselkupplung aus Figur 1;

Figur 3:

eine axonometrische Ansicht der Schnellwechselkupplung aus Figur 1;

Figur 4:

eine Draufsicht auf die Schnellwechselkupplung mit dem Bedienhebel in einer zweiten Position;

Figur 5:

eine Draufsicht auf die Schnellwechselkupplung mit dem Bedienhebel in der zweiten Position und dem Schliesselement in einer Offenposition;

Figur 6:

eine Seitenansicht der Schnellwechselkupplung aus Figur 5

Figur 7:

eine Draufsicht auf die Schnellwechselkupplung mit dem Bedienhebel in einer dritten Position und dem Schliesselement in der Offenposition und

Figur 8:

eine axonometrische Ansicht der Schnellwechselkupplung aus Figur 6.

Further advantages and features will become apparent from the following description of an embodiment of the invention with reference to the schematic representations. It shows in not to scale representation:

FIG. 1:

a plan view of a semi-automatic quick-change coupling for attaching an attachment to an excavator with a closing element in a closed position and a control lever in a first position;

FIG. 2:

a side view of the quick-change coupling FIG. 1 ;

FIG. 3:

an axonometric view of the quick-change coupling FIG. 1 ;

FIG. 4:

a plan view of the quick-change coupling with the operating lever in a second position;

FIG. 5:

a plan view of the quick-change coupling with the operating lever in the second position and the closing element in an open position;

FIG. 6:

a side view of the quick-change coupling FIG. 5

FIG. 7:

a plan view of the quick-change coupling with the operating lever in a third position and the closing element in the open position and

FIG. 8:

an axonometric view of the quick-change coupling FIG. 6 ,

In the FIGS. 1 to 8 a quick-change coupling is shown in various coupling positions, which is generally designated by the reference numeral 11. The quick-change coupling 11 comprises a receiving and fastening device, wherein in the figures, only the receiving device 13 is shown. The fastening device serves for the articulated fastening of the quick-change coupling 11 to an excavator arm. The receiving device 13 comprises a first and second jaw 15a, 15b in which a first retaining bolt of an attachment, such as an excavator bucket, is receivable. The claws 15a, 15b form a first insertion opening 16, in which the first retaining bolt is held. The receiving device 13 also includes a plate 17, on the longitudinal sides of the claws 15a, 15b are attached. For reasons of clarity, the plate 17 is shown transparent in the figures.

Between the jaws 15a, 15b, a closing element 19 is slidably disposed. The closing element 19 is guided in mutually facing grooves 21a, 21b ( FIG. 3 . 6 . 8th ). The closing element 19 is arranged along the grooves 21a, 21b between an open position (FIG. Figures 1 - 4 ) and a closing position ( FIGS. 5 to 8 ) displaceable. At the closing element 19, a second insertion opening 23 is provided. In the open position, an attachment can be connected or disconnected. In the closed position, the second retaining pin of the attachment is also held on the receiving device 13 by the retaining bolts are engaged and clamped by the insertion openings 16,23.

On the underside of the plate 17, an operating lever 25 is rotatably disposed about a first joint 27. The operating lever 25 is arranged between the plate 17 and the closing elements 19.

The operating lever 25 has a first and a second end 29, 31. The first end is formed as a first hand lug in the form of a hook 33. Thus, the operation of the operating lever 25 is facilitated because the operator can place a finger on the hook 33 and the operating lever 25 can rotate counterclockwise.

At the second end 31, a slotted guide 35 is provided, which has the shape of a Z's. The slide guide thus has a first and second crossbar 37,39, which are mutually arranged at the ends of a longitudinal beam 41. The slotted guide 35 cooperates with a guide element. The guide element is preferably a pin 43, which is fastened to the closing element 19 and projects into the slotted guide 35.

With the operating lever 35, a rod 45 is pivotally connected. The first end of the rod is formed as a second hinge 47. Preferably, the first end of the rod 45 is circular in shape and is received in a formed on the operating lever Gelenkpan 46. This form of joint connection is particularly low. Additional holding means can be dispensed with since the second hinge 47 is bounded by the plate 17 and the closing element 19. The distance between the plate 17 and the closing element 19 is predetermined by the height of the operating lever 25 and is not increased by the second hinge 47.

The rod 45 has following the first end a bend 48, which is adapted to the outer contour of the operating lever 25. As a result, the rod 45 can bear on the operating lever 25 when it is in the first position and the position change of the operating lever 25 is not in the way.

The second end 51 of the rod 45 is guided on a transverse web 49 by the rod 45 is inserted through a first passage opening 53 of the transverse web 49.

The transverse web 49 serves as a support for two spring elements 55, which are arranged between the transverse web 49 and the closing element 19. The ends of the spring elements 55 are fastened to the transverse web 49 or to the closing element 19. The spring elements 55 may be gas springs, coil springs or other elastic elements with a sufficient restoring force.

On the rod 45, a first projection 57 is formed. On the rod 45, a spring 59 is attached, which is compressible between the first projection 57 and the cross bar 49.

On the plate 17, a second elongated passage opening 61 is provided. Retaining grooves 63a, 63b are formed on the longitudinal sides of the second through-opening 61. In the second passage opening 61 can be an L-shaped clamping lever 60 with a transverse axis 62 and a second hand lug 64 in the form of a handle. The transverse axis 62 can be received in the retaining grooves 63a, 63b, whereby the clamping lever is rotatable about the transverse axis. The tensioning lever protrudes with its shorter end through the second passage opening 61.

On the plate 17, a through-opening 65 is provided. Through the access opening 65 of the hook 33 of the operating lever 25 is reached. The plate 17 projects beyond the hook 33, whereby the operating lever 25 is protected, in particular against being bent or broken off.

The following paragraphs describe the operation of the quick-change coupling 11:
First, the quick-change coupling 11 must be pre-tensioned for coupling an implement or uncoupling the attached implement. For this purpose, the clamping lever is inserted into the second passage opening 61. If the tension lever is pressed down, its shorter end presses against the spring pressure of the spring elements 55, the closing elements 19 from the closed position to the open position.

Due to the shape of the slotted guide 35 and their interaction with the pin 43, the operating lever 25 can be pivoted between a first, a second and a third position.

In the FIGS. 1 and 3 It is shown that the operating lever 25 is in the first position. In this position, the pin 43 is received in the first crossbar 37. Since the pin 43 is fixedly connected to the closing element 19, the closing element 19 is locked in the first position of the operating lever 25 and can not be moved from the closed position. This is important so that an attached to the quick-change coupling 11 attachment can not be accidentally disconnected from the clutch 11.

With one hand, the operator can pivot the operating lever 25 by means of the hook 33 in the second position and thereby unlock the closing element 19 ( FIG. 4 ). The operating lever 25 is in the second position when the pin 43 is at the transition from the first crossbar 37 to the longitudinal beam 41. The operating lever 25 can be turned counterclockwise against the pressure of the spring 59. The spring pressure causes the operating lever 25 automatically rotates clockwise when it allows the slide guide 35.

With the other hand, the operator can push the clamping lever down whereby the closing element 19 is pressed from the closed position to the open position. In this case, the pressure of the spring elements 55 must be overcome and these are compressed or biased in the open position. The pin 43 can slide during the transition from the closed position to the open position and vice versa along the longitudinal beam 41 of the slotted guide 35 ( FIG. 5 ).

In order for the closing element 19 to remain in the preloaded open position, it must be locked. For this purpose, the operating lever 25 is further counterclockwise to rotate in the third position until the pin 43 abuts the end of the second crossbar 39 of the slotted guide 35.

If the operating lever 25 is relieved, the pin 43 is pressed by the bias of the spring elements 55 in the end of the second crossbar 39. As a result, the operating lever 25 locks the closing element 19 in the open position. At the transition between the longitudinal beam 41 and the second crossbar 39, a second projection 67 is formed which reliably holds the pin 43 in the end of the second crossbar 39. This ensures that the pin 43 is not pressed into the longitudinal beam 41 by the bias of the closing element.

The bias of the operating lever 25 in the third position caused by the spring 59 allows the operating lever 25 is automatically shifted back to the first position when the closing element 19 is automatically closed.

In addition to the return of the operating lever 25, the rod 45 has another function. It performs a control function by indicating to the operator whether the quick-change coupling is open or closed. If the second end 51 of the rod 45 protrudes from the transverse web 49 and is visible, then the closing element 19 is in the open position. If the second end 51 is not visible, then the closing element 19 is in the closed position.

For automatically coupling an attachment, the first retaining bolt is to be received in the claws 15a, 15b. Then the excavator arm is to be moved so that the second retaining pin presses the closing element 19 from the open position slightly backwards against the closed position. As a result, the pin 43 loses contact with the slotted guide and the operating lever snaps by its bias in the second position. As a result, the closing element is unlocked and is pressed by the spring elements 55 in the closed position. In the closed position, the second retaining bolt is received in the second insertion opening 23. The pin 43 is in the closed position, the rod 45 can press the operating lever 25 by the bias of the spring 59 in the first position. As a result, the closing element 19 is automatically locked in the closed position by the operating lever 25.

If the quick-change coupling 11 is not used for a long period of time, then the closing element 19 can be transferred into the closed position with the aid of the clamping lever and thereby relaxed, without an attachment being coupled. For this purpose, the closing element 19 is to be pressed with the clamping lever beyond the open position. As a result, the operating lever is released and can be rotated by its bias from the third position to the second position. Then, with the help of the clamping lever, the closing element 19 can be metered into the closed position.

The invention discloses a semi-automatic quick-change coupling 11. The biasing or uncoupling of the attachment is done manually by means of a clamping lever. The attachment is coupled automatically without the operator having to get out of the cab of the excavator. The snapping of the second retaining bolt of the attachment in the second insertion opening 23 is made possible by the bias of the closing element 19 in the open position. The user of the coupling 11 must use both hands in order to bias the closing element 19 and dosed to relax. The operation of the clutch 11 is therefore very safe and hand injuries are avoided.

Legend:

11

Quick-change coupling

13

cradle

15a, 15b

First and second claw

16

First insertion opening

17

plate

19

closing element

21a, 21b

groove

23

Second insertion opening

25

operating lever

27

First joint

29

First end of the control lever

31

Second end of the control lever

33

First hand approach, hook

35

link guide

37

First crossbeam

39

Second crossbeam

41

stringers

43

Pen, guide element

45

pole

47

Second joint, first end of the rod

48

bending

49

crosspiece

51

Second end of the rod

53

First passage opening

55

spring elements

57

First advantage

59

feather

60

clamping lever

61

Second passage opening

62

transverse axis

63a, 63b

retaining

64

Second hand approach, grip

65

Through opening

67

Second advantage

Claims (16)

Quick change coupling (11) for attaching an attachment to a construction machine, preferably on an excavator with a receiving and fastening device (13), - A fixed first insertion opening (16) which is formed or fixed to a first end of the receiving and fastening device (13), and - One on the receiving and fastening device (13) arranged, movable closing element (19) having a second insertion opening (23), which can be moved from an open position in which an attachment can be connected or disconnected, in a closed position in the retaining bolts of the attachment are engaged and clamped by the insertion openings (16, 23), the closure element (19) being biased and lockable in the open position, characterized,
in that on the receiving and fastening device (13) an operating lever (25) is movably arranged, which has a first hand attachment (33), whereby it can be operated with the first hand of the user of the coupling (11) and which operating lever (25) the closing element (19) in the open and in the closed position locked and unlocked and
in that the coupling (11) comprises a tensioning lever (60) with a second hand attachment (64), whereby the tensioning lever (60) can be operated simultaneously with the operating lever (25) for pretensioning and for relaxing the closing element (19) with the second hand of the user is. Coupling according to claim 1, characterized in that the operating lever (25) between a first position in which the operating lever (25) locks the closing element (19) in the closed position, a second position in which the closing element (19) between the closing position and the Oven position is movable and a third position in which the operating lever (25) locks the closing element in the open position, is movable. Coupling according to claim 1 or 2, characterized in that the operating lever (25) between the receiving and fastening device (13) and the closing element (19) is arranged and is rotatably hinged to the receiving and fastening device (13). Coupling according to one of the preceding claims, characterized in that on the operating lever (25) has a slotted guide (35) is provided which cooperates with a on the closing element (25) arranged guide element (43) which engages in the slotted guide (35). Coupling according to claim 4, characterized in that the guide element (43) in the slotted guide (35) can be latched when the operating lever (25) is in the third position. Coupling according to claim 4 or 5, characterized in that the slide guide (35) is substantially a Z-shaped recess. Coupling according to one of claims 2 to 6, characterized in that the operating lever (25) is biased in the third position. Coupling according to one of the preceding claims, characterized in that the operating lever (25) is pivotally connected to a first end (47) of a rod (45) and a second end (51) of the rod (45) by a on the receiving device (13 ) arranged transverse web (49) is passed. Coupling according to claim 8, characterized in that on the rod (45) a spring (59) is fitted, which between a on the rod (45) provided projection (57) and the transverse web (49) is compressible. Coupling according to one of the preceding claims, characterized in that the clamping lever of the coupling (11) is removable and on the receiving and fastening device (13) has a passage opening (61) is provided, in which the clamping lever for displacing the closing element (19) from the closed position in the open position against the bias voltage can be suspended. Coupling according to one of claims 2 to 10, characterized in that the closing element (19) beyond the open position against the direction of the closing position is displaced, whereby the operating lever (25) can move automatically from the third position to the second position. Coupling according to one of claims 2 to 11, characterized in that on the receiving and fastening device (13) has a passage opening (65) is provided, through which the operating lever (25) between the first, the second and the third position is movable. Coupling according to one of the preceding claims, characterized in that the closing element (19) with a spring element (55) is biased in the open position. Coupling according to claim 13, characterized in that the spring element (55) with the closing element (19) and the transverse web (49) is connected. Method for pretensioning and relaxing a closing element (19) of a quick-change coupling (11) according to one of the preceding claims
a user of the clutch with his first hand moves a clamping lever (60), whereby the closing element (19) is moved from a closed position to an open position, in which open position, the closing element (19) is biased and locked
characterized,
that the user at the same time with his second hand operated on the clutch (11) movably arranged operating lever (25), wherein the operating lever (25) by its corresponding movement releases the movement of the closing element (19) in the open position and
by a further movement of the operating lever (25), the closing element (19) is locked in the open position. A method according to claim 15, characterized in that the closing element (19) is moved from the open position to the closed position
on the one hand, by an attachment which is coupled to the coupling (11), the locking of the operating lever (25) by moving the closing element (19) opens and
on the other hand, the user of the clutch (11) operates the clamping lever (60) with his first hand and the operating lever (25) operated simultaneously with his second hand, whereby the closing element is moved in doses from the open position to the closed position.

Images