AU1257301A - A quick coupler assembly - Google Patents

Description

WO 01/34916 PCT/AUUU/01375 1 A QUICK COUPLER ASSEMBLY TECHNICAL FIELD This invention relates to an assembly for coupling or hitching implements to heavy machinery. In particular, the present invention is 5 directed towards a quick coupler assembly. BACKGROUND ART Implements conventionally fitted to heavy machinery include those suitable for loading, working or carrying loads such as a bucket, dipper bucket, fork lift unit, hydraulic shovel, grader or drill unit. Conventionally, the 10 implements are fitted to the heavy machinery by manually inserting large cast steel pins through holes in plates formed on the implements and in the operating arm of the machinery. This is a time consuming and tedious process. The operator must also alight from the controls or employ the services of an assistant. 15 To rectify this, quick coupler or quick hitch assemblies have been proposed. These assemblies normally enable the connection of the implement to the heavy machinery to be effected automatically by the operator, that is, without the need to alight from the controls of the machinery. None however is completely satisfactory for one reason or another. Other 20 types of quick coupler or hitch assemblies have a hydraulically activated hook. A significant disadvantage of this coupler is that if the hydraulic pressure drops and/or there is a break in one of the hydraulic lines, the implement may become detached. Conventional quick hitch or coupler assemblies are mounted to 25 the operating arms of heavy machinery by inserting pins through holes in the operating arms of the machinery and holes in plates on the rear of a quick hitch or coupler. In other words, these types of assemblies are an "add on" to the vehicle frame. This may affect the balance and operating dimensions of the machinery and arm. For example, bucket lifting or digging forces are 30 proportional to such factors as the length of the operating arms, bucket angle, and the like. Generally, the dimensions of operating arms of heavy WO 01/34916 PCT/AUOU/01375 2 machinery, the location of pivot points and bucket angles are calculated by the manufacturer to optimize operation. Addition of a quick coupler or hitch to the operating arm alters these dimensions, which may adversely affecting operation of the machinery. 5 It is therefore and object of the present invention to provide an assembly for mounting an implement to an operating arm of heavy machinery which may at least partially overcome the above disadvantages or provide the public with a useful choice. DISCLOSURE OF THE INVENTION 10 According to a first broad form of the invention there is provided an assembly for attaching a hydraulic arm of heavy duty machinery to an implement having a pair of outwardly extending connector brackets, the assembly having a body and at least one connecting pin for connecting the body to the hydraulic arm, wherein the at least one connecting pin is also 15 engagable with the connector brackets such that when the assembly is connected to the hydraulic arm, the at least one connecting pin can engage the implement. The assembly may be used to coupler or hitch any suitable type of implement. Such implements include, but are not limited to multi-purpose 20 buckets, hydraulic shovels, rippers or drill units. The assembly can be mounted to the hydraulic arm of any type of heavy machinery suitable for operating such implements and includes excavators, back-hoes, bull dozers, front-end loaders, tractors, graders and hydraulic shovels. The at least one connecting pin typically connects the hydraulic 25 arm and assembly by passing through respective pinholes on the arm and assembly body. Hydraulic arms of heavy machinery typically have a main arm and a secondary tilting arm. The tilting arm has a hydraulic cylinder, which can be actuated to tilt or pivot an implement about a pivot point. When there 30 is no coupler or hitch fitted to the arm, the implement pivots about the connection point between the arm and implement. Where a conventional coupler or hitch is fitted, the implement pivots about the connection point WO 01/34916 FC'I/AUUU/Ul17t 3 between the implement and the hitch or coupler. However, with the assembly of the present invention, the connecting pin connects both the assembly and the implement to the arm such that the point about which the implement pivots, remains at the end of the arm, where the manufacturer designed it to 5 be. The assembly may have a single connecting pin, which can extend through respective pin holes in the arm and assembly body. In a preferred embodiment of the present invention, the connector pin(s) can be actuated to move between an implement engaging position and an implement 10 release position. Typically the connecting pin(s) is actuated by a hydraulic ram. The assembly may be connected to the main hydraulic system of the machinery. Typically the connector brackets of the implement house pin holes through which the connection pin(s) can pass. Preferably, the assembly has two connector pins 15 Typically, the assembly includes indicating means to indicate to an operator in a cabin that the connecting pin(s) are in the engagement or release positions. The assembly may include at least one pair of parallel load transmitting plates, which include the pin holes through which the connecting 20 pin(s) passes. The number of load transmitting plates is typically dependant upon the type of linkage, the size of the machinery and the loads and/or use to which the implement may be subjected in use. For a typical three point linkage arm having two main arms and a secondary arm, the assembly typically includes two pairs of parallel load transmitting plates, each pair of 25 plates supporting a pin, each pin connecting the assembly to a respective main arm. The assembly typically includes a further means for engaging the assembly to an implement. Any suitable type of engagement means may be used, such as those used on conventional quick hitches or couplers. 30 Typical methods for engagement include hook members s located on either the assembly or implement engagable with projections such as bars, pins or lugs located on the other of the implement or assembly.

WO 01/34916 PCT/AUOO/01375 4 Typical implements such as buckets or the like have a lower region adapted to be located closest to a ground surface and an upper region. Typically the at least one connecting pin engages the lower region of the bracket and the further implement attachment means engages the upper 5 region of the implement. Typically the assembly includes projections which in use can engage hook members extending from the upper region of the implement. Typically each of the outwardly extending connector brackets of the implement has a hook member located in an upper region thereof. Typically, the assembly includes locating means for locating the 10 implement relative to the assembly during engagement of the implement so as to correctly align the connector pin(s) with the implement. In one form the locating means includes a pair of opposed projections such as bump stops which can hold the implement in the desired position relative to the assembly during the attachment procedure. 15 Secondary tilting arms of hydraulic arms of heavy machinery are conventionally attached to the couplers or hitches by a pin passing through holes in a coupler or hitch and the hydraulic arm. In practice, this method of attachment can result in large stresses being placed on the connecting pin and coupler or hitch. This is particularly the case if the implement is subjected 20 to excessive loads. It is often difficult for an operator to detect whether overloading has occurred and it may be difficult to avoid damage to the coupler or hitch. One method of strengthening the attachment between the secondary arm and a hitch or coupler is to provide a pair of secondary arms, as for example in a four point linkage hydraulic arm. However, the cost of a 25 four point linkage as compared to a three point linkage arm can be considerable. Other attempts at solving this problem have concentrated on providing reinforcement about the attachment point. This increases the complexity and cost of the assembly. According to a further broad form of the invention, there is 30 provided an assembly for attaching an implement to a hydraulic arm of heavy duty machinery having a main arm and a secondary arm, the assembly having a body, a first attachment means for attaching the assembly to the WO 01/34916 PCT/AUUU/01375 5 main arm and a second attachment means for attaching the assembly to the secondary arm, the second attachment means including a connecting arm having a first end pivotally connected to the body and a second end attachable to the secondary arm. 5 With conventional quick coupler assemblies, stresses occur at the attachment point between the implement and the secondary arm. By providing a connecting arm for connecting the assembly to the secondary arm, the point at which the main stress occurs is located at the pivotal connection point between the connecting arm and the body of the assembly. 10 This enables the assembly to be constructed such that the connection between the body and connecting arm is stronger or more robust than conventional link pins, which connect a secondary arm to a coupler. The other end of the connecting arm may be attached to the secondary arm by a conventional link pin. 15 Typically the first attachment means when attached to the main arm can also attach the assembly to the implement as described in the first broad form of the invention in which at least one connecting pin connects the assembly to both the implement and the hydraulic arm. The assembly of either form of the invention can be readily 20 connected to the existing arms of a vehicle. When connected, the assembly becomes part of the vehicle frame and need not be removed. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective top view of a preferred assembly of the present invention, 25 Figure 2 is a perspective bottom view of the assembly of Figure 1, Figure 3 is an exploded view of the assembly of Figure 1, Figure 4 is a perspective view of a further preferred assembly of the invention, 30 Figure 5 is the assembly of Figure 4 with the connecting arm removed, WO 01/34916 PC'1/AUUIUIi/:) 6 Figure 6 is an exploded view of the connecting arm of the apparatus of Figure 4, Figure 7 is a schematic view of the assembly of Figure 1 attached to a hydraulic arm of a loader, 5 Figure 8 is a side view of an implement mounted to the hydraulic arm of a front end loader using the assembly of Figure 1; Figure 9 is a rear view of an implement mounted to the hydraulic arm of a front end loader using the assembly of Figure 1 and Figure 10 is a front view of an implement mounted to the 10 hydraulic arm of a front end loader using the assembly of Figure 1; DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION Figure 1 illustrates a preferred assembly 11 of the present invention, which is in the form of a quick coupler. The coupler has two pairs 15 12, 13 of parallel load transmitting plates. The outer plates 12a, 13a have lugs 14, 15 and bump stops 8, 9 extending therefrom. Pins 16, 17 are located at the lower section of the coupler. The pins 16, 17 are actuated by a hydraulic ram 7. The ram 7 is protected from dirt and dust by housing 18. The ram 7 can be seen more clearly in Figure 3. Apertures 19, 20 are located 20 in the respective outer plate 12a, 13a of the plate pairs 12, 13. The ram can be actuated to move pins 16, 17 between a retracted position (as shown in Figures 1 and 2) and an engagement position in which the ends of the pins 16, 17 extend thorough apertures 19, 20. Pointers 21, 22 extend from housing 18. The pointers 21, 22 25 are connected to ram 7 as shown in Figure 3. The pointers 21, 22 move as the ram 7 withdraws or extends pins 16, 17. This enables an operator at the controls of a heavy machinery vehicle to determine whether the pins are withdrawn or extended by observing the direction in which the pointers are pointing. 30 The coupler has a T shaped connecting arm 30 with an elongated cylindrical end portion. The end portion of the connecting arm is pivotally connected to the inner 12b, 13b of the pairs of load transmitting WO 01/34916 PCT/AUUU/01375 7 plates by spigots 31, 32, which engage opposite ends of the end portion. The other end 33 of arm 30 has an aperture 34 through which a link pin may pass to connect the arm 30 to a secondary arm of a heavy machinery vehicle. The arm 30 has reinforcing ribs 35, 36. It can be seen that the connection 5 between the arm and the body of the coupler 30 can be constructed such that it is much stronger than a conventional link pin connection between a coupler and a secondary tilt arm. Figures 4 and 5 illustrate a further preferred quick coupler 61 of the present invention. The coupler 61 is similar to that illustrated in figure 1 10 and the same reference numerals have been used to indicate like features. The connecting arm 30 of coupler 61 is connected to the coupler by means of a retainer pin 62 (more clearly seen in Figure 5 in which the coupler is shown without the connecting arm fitted thereto). The retainer pin 62 extends between load transmitting plates 12b, 13b. 15 The retainer pin 62 is secured in position by lock pin 63, which engages tongue 64 of pin 62. The other end of the retainer pin is secured by nut 65. Pin adapters 66, 67 are optionally placed at either end of pin 62 during assembly. The coupler operates off the normal hydraulic system of the 20 hydraulic arm to which it is mounted. Figure 7 is a schematic view of the coupler 11 attached to an arm 40 of a front end loader. The arm 40 has two main lifting arms 41, 42. The arms 41, 42 each have apertures 43, 44 through which pins 16, 17 pass to connect the arms 41, 42 to the coupler 11. The arm has a secondary tilt 25 arm 45, which is pivotally attached to connecting arm 30. Figures 8, 9 and 10 illustrate the coupler 11 and arm 40 of a loader mounted to a bucket 50. The bucket has a pair of parallel connecting brackets or ears 49, 51. The ears 49, 51 each have an upper hook 52 and a lower pin hole 53. Each ear 49, 51 has small recess 54 intermediate the hook 30 52 and pin hole 53. In use this recess abuts bump stops 89 on the coupler. The bucket 50 is mounted to the coupler 11 by driving the vehicle up to the rear of the bucket 50 until lugs 14, 15 engage the hooks 52 WO 01/34916 PCT/AU00/01375 8 on the bucket ears 49, 51. The main loader arms 42, 41 are then raised slightly so as to lift the bucket 50. When this happens bump stops 8, 9 abut recesses 54. This serves to locate apertures 53 adjacent pins 16, 17. The ram 7 can then be activated to insert drive pins 16, 17 through the holes 53 in 5 the bucket ears 49, 51. The pointers 20, 21 will indicate as to whether the pins have been engaged with the bucket ears. It can be seen that the assembly of the invention allows an implement to be hitched or coupled to a hydraulic arm of heavy machinery quickly and efficiently. 10 The implement will also remain securely hitched or coupled, even if there is a drop in hydraulic pressure in the hydraulic arm. Further, the pivot point of the implement with respect to the hydraulic arm is unaffected by the apparatus. This is in contrast to conventional hitches and couplers, which offset the pivot point from the arm. 15 Still further, the provision of a connecting arm for attachment to a secondary tilt arm provides a much stronger attachment than conventional link pins. Whilst the above has been given by way of illustrative example of the invention, many modifications and variations may be made thereto without departing from the broad scope and ambit of the invention as herein 20 set forth.

Claims (14)

1. An assembly for attaching a hydraulic arm of heavy duty machinery to an implement having a pair of outwardly extending connector brackets, the 5 assembly having a body and at least one connecting pin for connecting the body to the hydraulic arm, wherein the at least one connecting pin is also engagable with said connector brackets such that when the assembly is connected to the hydraulic arm, the at least one connecting pin can engage the implement. 10

2. The assembly of claim 1, which includes a hydraulic ram for moving the at least one connecting pin between an implement engaging position and an implement release position.

3. The assembly of claim 2, which further includes indicating means to indicate when the at least one connecting pin has engaged the implement. 15

4. The assembly of claim 1, having two pairs of parallel load transmitting plates, each pair of plates having a connecting pin associated therewith.

5. The assembly of claim 1, which includes a further means for engaging the implement.

6. The assembly of claim 5 for attachment to an implement having a lower 20 region adapted to be located closest to a ground surface and an upper region, wherein the at least one connecting pin engages the lower region and the further engaging means engages the upper region.

7. The assembly of claim 6, wherein the further engagement means includes a pair of lugs which can engage hook members on the implement. 25

8. The assembly of claim 7, which includes locating means for locating the assembly relative to the implement during engagement so as to correctly align the at least one connector pin with the connector brackets. WO 01/34916 PCT/AUUUIU1375 10

9. The assembly of claim 1, for attaching an hydraulic arm to an implement, the hydraulic arm having a main arm and a secondary tilt arm, wherein the assembly further includes a connecting arm having a first end pivotally connected to the body and a second end attachable to the secondary 5 arm.

10. A hydraulic arm for heavy machinery having the assembly of claim 1 attached thereto.

11. An assembly for attaching an implement to a hydraulic arm of heavy duty machinery having a main arm and a secondary arm, the assembly 10 having a body, a first attachment means for attaching the assembly to the main arm and a second attachment means for attaching the assembly to the secondary arm, the second attachment means including a connecting arm having a first end pivotally connected to the body and a second end attachable to the secondary arm. 15

12. The assembly of claim 11, wherein the assembly includes a pair of load transmitting plates and the first end is elongate and extends between the plates so as to be supported thereby.

13. The assembly of claim 12, which includes a retaining pin extending between the load transmitting plates and the first end has a bore through 20 which the retaining pin can pass.

14. A hydraulic arm of heavy machinery having the assembly of Claim 11 attached thereto. 25