QUICK COUPLING

Abstract: Quick coupling device for implement carrying machines (6, 7) such as loading machines and excavators. The device comprises an implement holder (1) carried by the implement and a suspension plate (5) carried by the machine, which cooperate for removable attachment of the implement (16) to the machine (6, 7). According to the invention the suspension plate (5) is provided with wedge shaped, preferably conic suspension elements (8), and the implement holder (1) is provided with suspension recesses (2) having the corresponding shape, so that the narrow ends of the suspension elements can be guided into the broad opening of the corresponding recesses (2) when the suspension plate is lifted upwards. The device is also provided with means (9), preferably hydraulic piston/cylinder units, for locking the suspension elements (8) in the corresponding recesses (2) while at the same time clamping the suspension plate (5) against the implement holder (1).

Description: Quick coupling. The present invention relates to a new type of quick coupling device for connecting and disconnecting an implement to an implement carrying machine. Examples of such machines are various types of construction machinery such as excavators, earth movers, loading machines, etc. Buckets, bulldozer blades, lifting forks, crane jibs, concrete pumping equipment, etc. can be mentioned as examples of implements which can be coupled to such machines. It should, however, be underlined that the invention is not limited to these especially mentioned implements and machines, but it can be applied in ail such cases when there is a need of coupling a working implement to a machine. In known devices of the indicated type the coupling usually takes place by hanging a yoke shaped top portion of the implement or implement holder over the top edge of a suspension plate on the machine, the locking between the two parts taking place by means of laterally acting pistons. These coupling devices have several drawbacks. For example, a very close fitting is required in the coupling, and the coupling procedure is time consuming - one could here not really talk about a quick coupling. Further, the known coupling devices leave much to desire as regards the stability of the coupling, % which is of decisive importance for making it possible to use the implement in the intended manner;. In particular, the known coupling devices are sensitive to wear which rapidly reduces the coupling stability. This in turn leads to great demands for maintainance and repair, which are comparatively time consuming and complex due to the design of the devices. There is thus a need of a simple and efficient device, which makes it possible to rapidly couple an implement to (and from) an implement carrying machine. It is an object of the invention to solve this problem and to provide a quick coupling device of the indicated type, which steadily locks the implement to the machine practically independent of the degree of wear of the coupling device, and which only requires little maintainance and repair. The subject matter of the invention is thus a device for the quick coupling of an implement to and from an implement carrying machine. The device is of the type which comprises an implement holder carried by the implement and a suspension plate carried by the machine, which cooperate for removable attachment of the implement to the machine. In accordance with the invention the suspension plate is provided with at least one suspension element having upwardly tapered cross- sectional shape, and the implement holder is provided with at least one suspension recess having corresponding upwardly tapered shape as the suspension element or elements. The suspension elements and recesses are so arranged that the suspension elements can be guided into the corresponding recesses when the suspension plate is moved upwards. In accordance with the invention the device is further provided with means for lockingly pressing the suspension elements into the corresponding suspension recesses while at the same time securing the suspension plate against the implement holder. Although the suspension elements on the suspension plate, for example, can have the shape of one or more elongate fillets (with corresponding suspension recesses in the implement holder) they preferably have the shape of a truncated cone, in which case the suspension recesses, of course, are shaped corresponding- ly. In this preferred embodiment at least two such suspension elements are utilized, preferably being mirror symmetrically located in relation to the vertical axis of the suspension plate. . The suspension elements are at their broader base portions preferably so designed that they are again tapered below the base portion, so that the suspension elements upon wear freely can further penetrate the respective suspension recesses. These recesses are in a corresponding manner provided with a free play at their upper, narrower end portion, so that further penetration of the suspension elements into the recesses is not hindered upon wear. For larger loading machines such a free play at the lower portion of the suspension elements and at the top portion of the suspension recesses respectively is suitably at least about 10 mm, for example 10 to 30 mm. The locking devices for pressing the suspension elements into the corresponding suspension recesses and securingly pressing the suspension plate against the implement holder preferably comprises one or more piston/cylinder units, which are carried by the suspension plate and cooperate with corresponding stop means provided on the implement holder. These stop means are preferably designed as half wedge-shaped locking recesses, into which corresponding "half wedges" on the piston/cylinder unit can be inserted. Upon insertion of the half wedges into the locking recesses by means of the piston/cylinder units, the same will press the suspension elements into the corresponding suspension recesses while at the same time pressing the suspension plate against the implement holder. In this manner an extremely good locking of the implement to the suspension plate in ail directions is obtained, and this locking remains as efficient even when the various suspension details are subjected to normal wear. A few suitable embodiments of the invention will now be described in more detail with reference to the enclosed drawings, in which Fig. la is a schematic side elevation view showing the principle of the implement holder according to the invention, Fig. lb is a schematic half perspective view showing the principle of the suspension plate according to the invention, Fig. 2 is a rear view of a first embodiment of the suspension plate according to the invention, Fig. 3 is a rear view of a second embodiment of the suspension plate according to the invention, Fig. 4 is a schematic partial view illustrating the interconnection of a suspension plate and an implement holder according to the invention, Fig. 5 is a partial view taken along the arrows A-A of Fig. 2 and schematically showing a preferred embodiment of the suspension elements of the device according to the invention, , Figs. 6 and 7 are part views from above (taken according to the arrows B-B in Fig. 2) and in side elevation respectively, showing a preferred embodiment of the locking means in the device according to the invention, and Fig. 8 is a schematic side elevation view showing an implement holder according to the invention attached to an excavator.. The implement holder shown in Fig. la comprises a vertical holder plate la having a top piece lb projecting therefrom. A conic suspension recess 2 is provided in the top piece lb. The implement holder 1 is at its lower portion provided with stop means 3 having a "half" wedge-shaped locking recess, which is illustrated by the dashed line . The implement holder shown in Fig. la is intended to cooperate with the suspension plate 5 shown in Fig. lb. Fig. lb schematically shows how the plate 5 is intended to be connected to a load arm 6 and a rocker arm 7 on the vehicle intended to use the implement attached to the implement holder I. At the top of the suspension plate 5 there are two (or more) firmly secured suspension elements 8, each of which in the shown embodiment having the shape of a truncated cone. This truncated cone has a corresponding inclination and dimensions as the suspension recesses 2 in the top piece lb of the implement holder 1. The suspension plate 5 further carries a piston/cylinder unit 9, which preferably is hydraulic and connected to the hydraulic system of the carrier vehicle. The piston/cylinder units are preferably controlled by means of suitable control means (not shown) located in connection to the driver's seat in the carrier vehicle. The cylinder part 10 of the piston/cylinder unit is in suitable manner attached to the suspension plate 5, whereas its piston part 11 is connected to a locking bolt 13, preferably by means of a suitable connecting piece 12. The free end 13a of the locking bolt 13 is designed as a locking wedge fitting into the locking recess of the implement holder 1. The locking bolt 13 is preferably held in the proper position on the suspension plate 5 by means of a guide sleeve 14. At the locking bolt 13 the suspension plate 5 is provided with an opening 15, through which the stop piece 3 (having the locking recess 4) of the implement holder 1 is intended to pass. The quick coupling device according to the invention essentially operates in the following manner. When an implement, for example the bucket 16 shown in Fig. 8, is to be coupled to the machine, the load arms 6 and rocker arms 7 of the implement carrying machine are operated such that the suspension cones 8 on the suspension plate 5 from below are moved towards the corresponding suspension recesses 2 in the top piece lb of the implement holder. As soon as the narrow top portion of the conic suspension elements has entered the broad bottom portion of the conic suspension recesses 2, an automatic guiding to the correct position takes place because of the conic shape of the two elements. In this manner wide margins of error are permitted in the adjustment between the suspension plate 5 and the implement holder 1. Therefore, the operator can make a rough positioning of the suspension plate in relation to the implement holder from the driver's seat of the machine, whereas the fine adjustment takes place automatically because of the conic shape of the suspension details. At the same time as the suspension cones 8 are inserted into the recesses 2, the stop piece 3 of the implement holder 1 will be inserted through the opening 15 of the suspension plate , so that the locking recesses 4 will be located on the opposite side of the suspension plate 5 (compare Fig. 7). The final locking of the implement holder 1 (and consequently of the implement 16) on the suspension plate 5 (and consequently on the carrying machine) takes place by actuation of the piston/cylinder unit 9. In the starting position said unit is in the position shown in Fig. lb, the locking bolt 13a essentially being in a retracted position above the opening 15 so that the stop piece 3 freely can be passed through said opening. When the suspension cones 8 have been fitted into the suspension recesses 2, the piston/cylinder unit 9 is actuated so as to expell the piston 11 from the cylinder 10. The locking wedge 13a will then enter the correspondingly shaped locking recess , the suspension cones 8 being lockingly pressed into the suspension recesses 2. Because of the wedge shape of the locking bolt 13a and the corresponding locking recess , the suspension plate 5 will at the same time be lockingly pressed against the holder plate la (see also Fig. 7). In this manner an extremely stable locking is obtained between the suspension plate 5 and the implement holder 1 in all directions. It is to be noticed that this locking effect will be essentially uneffected by the wear of the suspension details 2, 8 and the locking details , 13a, since upon such wear the suspension cones 8 only will be OMPI IFO pressed further into the corresponding suspension recesses 2 and the locking bolt 13a be pressed further into the corresponding locking recess as the details are being worn. A prerequisite for enabling the suspension cones 8 and the locking bolts 5 13a to be pressed further into the corresponding recesses upon wear is, of course, that such a further pressing insertion can take place essentially unhindered. In other words, the suspension cones 8 and the suspension recesses 2 (as well as the locking bolts 13a and the locking recesses ) should be designed such that they can be moved freely further into the recesses and freely receive further 10 penetration of the cones respectively. A preferred way of achieving this is illustrated in Fig. 4, which shows a suspension cone 8 inserted into a suspension recess 2 in unworn condition. The desired "wear margin" of the recess 2 is provided simply by an extension 2a of the conic recess 2. A play a_ between the bottom portion of the top piece lb and the top portion of the suspension plate 5 15 makes possible free penetration of the suspenion cone 8 into the recess 2 (2a) upon wear. In, for example, heavier loading machines the play a ought to be of the order of 10 to 30 mm. The suspension cones 8 can in a corresponding manner as for conic recesses 2 at their bottoms be provided with an extension of the conic shape, but according to a preferred embodiment the suspension elements 8 20 are designed as "double cones", i.e. at their bottom portions merging into a second, downwardly tapered conic portion 8a. In i.a. this embodiment the cones themselves are exchangeable, which makes possible a very quick and simple change of suspension cones 8 when needed. The suspension elements 8 may with their conic portions 8a be attached in holders 17 by means of suitable bolt joints 25 18 or the like (see Fig. 5). The holders 17 are rigidly secured to the suspension plate 5, preferably welded on the same, and they are provided with conic attachment recesses 19, corresponding to the shape of the portion 8a. Upon wear of the suspension elements 8 the same can thus in a simple manner be exchanged by loosening the bolt joint 18 and attaching a new suspension element 8. A 30 further advantage of this design is that it is possible to compensate for wear of the portions 8a, 19 in corresponding manner as for the suspension cones 8 and the corresponding recesses 2a by tightening the bolt joint 18. Figs. 6 and 7 illustrate a preferred embodiment of the locking recesses 4 and the corresponding locking wedges 13a. In this embodiment these elements 35 have the corresponding shape as the suspension cones 8 and the suspension recesses 2 respectively, with the exception that the locking details only have "half" conic shape, i.e. the shape of truncated cones which are severed essentially along their diameter plane. This embodiment of the locking elements offers the corresponding advantages as the preferred embodiment with conic suspension elements 8 and conic locking recesses 2 as regards fitting margin for the locking wedges 13 into the recesses h, insensitivity to wear, rigid locking in all directions, etc. It should, however, be underlined that the locking elements and 13a are not limited to this preferred embodiment, but the invention is also intended to comprise all other wedge shapes, which provide for pressing of the locking elements 8 into the recesses 2 and at the same time clamp the suspension plate 5 against the implement holder 1. Fig. 2 shows a preferred embodiment of a suspension plate in a quick coupling in accordance with the invention, primarily intended for heavier loading machines and the like. In this embodiment the device comprises two piston/- cy Under units 9 (preferably hydraulic), which are located symmetrically at the sides of the suspension plate 5. The hydraulic cylinders 10 are firmly secured to the suspension plate 5 in any suitable manner, e.g. by means of attachment brackets 20. The hydralic piston 11 is provided with a yoke portion 12a, which via a shaft 12c is journalled on an intermediate piece 12b connected to the lock bolt 13 (compare Fig. 7). In the shown case the suspension plate 5 is provided with three suspension cones 8, which are arranged mirror symmetrically in relation to the vertical centre line 9 of the device. The suspension elements 8 are designed as described with reference to Fig. 5. The suspension plate 5 is further provided with two mountings 6a for attachment of the suspension plate to the load arm of the relevant carrier machine and with two upper mountings 7a for attachment to the rocker arm of the machine. The implement holder 1 is correspondingly provided with three similarly located suspension recesses and two stop pieces arranged to pass through the respective openings 15 of the suspension plate 5. Fig. 3, finally, shows an alternative embodiment of a suspension plate for a quick coupling according to the invention, which is especially intended for coupling of relatively light weight implements, for example a bucket (compare Fig. 8 ) to an excavator. Since the forces in this case are not as great, it is often sufficient with one single centrally arranged piston/cylinder unit 9 and two suspension cones 8, which are symmetrically arranged and located in the vicinity of the sides of the suspension plate 5. The suspension cones 8 and the piston/cylinder units 9 are designed and operate fully in analogy with the earlier described embodiment. Fig. 3, however, illustrates an alternative attachment of the piston/cylinder unit 9 to the plate 5. In this embodiment the suspension plate 5 is provided with an attachment bracket 20a, which is secured, preferably welded, to the suspension plate, and which carries the cylinder part 10 of the piston/cylinder unit 9 by means of a shaft 21 passing through the attachment yoke. The invention is, of course, not restricted to the embodiments described above and especially shown in the drawings, but many modifications and variations are possible with the general inventive idea, as it appears from the subsequent claims.

Claims: CLAIMS 1. A device for quick coupling of an implement (16) to and from a implement carrying machine (6, 7) such as a loading machine, an excavator or th like, comprising an implement holder (1) carried by the implement (16) and suspension plate (5) carried by the machine, which cooperate for removabl attachment of the implement (16) to the machine (6, 7), characterized in th the suspension plate (5) is provided with at least one suspension element ( having upwardly tapered cross-sectional shape, and in that the implement holde (1) is provided with at least one suspension recess (2) having the correspondin upwardly tapered shape as said suspension element (8), said suspension elemen (8) and suspension recess (2) being arranged such that the narrow ends of th suspension element or elements (8) can be guided into the broad opening of th corresponding recesses (2) when the suspension plate is lifted upwards, the devic also being provided with means (9) for locking said suspension elements (8) in th corresponding recesses (2) while clamping the suspension plate (5) against th implement holder (1). 2. A device according to claim 1, characterized in that the suspensio • elements comprise at least two elements (8) having the shape of a truncate cone, and in that a suspension recess (2) having the corresponding conic shap corresponds to each such suspension element. 3. A device according to claim 1 or 2, characterized in that the means ( for locking said suspension elements (8) in said suspension recesses (2) compris at least one stop means (3, 4) provided on the implement holder (1) and at leas one corresponding expansion device (9-13) which is provided on the suspensio plate (5) and can be expanded so as to make contact with the corresponding sto means (3, 4) while pressing said suspension elements (8) into the correspondin suspension recesses (2). 4. A device according to claim 3, characterized in that said expansio device comprises at least one hydraulic, hydropneumatic or pneumatic piston/ cylϊnder unit (9). 5. A device according to claim 3 or 4, characterized in that each of sai stop means (3) comprises a wedge shaped locking recess (4), which is tapere from the end facing the suspension recesses (2), and in that each expansio device comprises a locking wedge (13a) having the corresponding wedge shape a said locking recess (4), so that upon pressing of the locking wedge (13a) into th locking recess (4) the suspension plate (5) is clamped against the implemen holder (1) at the same time as the suspension elements (8) are pressed into th OM corresponding suspension recesses. 6. A device according to claim 5, characterized in that the locking recesses (4) and the corresponding locking wedge (13a) have the shape of a half a truncated cone, i.e. a truncated cone which is severed along the diameter plane. 7. A device according to any one of the preceding claims, characterized in that the suspension elements (8) are removably attached to the suspension plate (5). 8. A device according to claim 7, characterized in that the suspension elements (8) are provided with attachment portions (8a) having the sha ~ pe of truncated cones of opposite conicity, and in that the conic attachment portions (8a) are removably attached in corresponding conic recesses (19) provided on the suspension plate. 9. A device according to any one of the preceding claims, characterized in that the suspension elements (8) are unhindered to penetrate into an efficient locking position within the suspension recesses (2) upon wear of the suspension elements and/or of the corresponding suspension recesses. 10. A device according to claim 9, characterized in that the unhindered penetration of the suspension elements (8) into the corresponding suspension recesses (2) is obtained by the latter being deeper (2a) than the depth of penetration of the suspension elements (8) in unworn condition, and in that there is a free play (a) between the suspension plate (5) and the suspension recesses, said play permitting further penetration of the suspension elements (8) into the suspension recesses (2, 2a). O PI r. W1PO .

Inventors: GREN J
Applicants: GREN J
Application year: 1981
Main classification: E02F3
IPC codes: E02F3