TRACTOR AND GROUND WORKING IMPLEMENT

Abstract: A loader (20) has a mast (22) which is releasably attach­ able to the front end of a tractor (10) by forward and rear­ ward mounting structures (34, 26, 34a). These forward mount­ ing structures comprise mounts (62, 62a) on the tractor (10) and mounts (84, 148) on the mast (22) which come into engagement on the mast (22) being swung upwardly about the rearward mounting structures (26). The associated mounts (62, 84 and 62a, 148) have co-operating guide faces which direct the mast mounts (84, 148) into abutment with a stop (68, 180) on the tractor mounts (62, 62a) which limits up­ ward movement. The mast (22) is prevented from downward swinging movement by a cam in the form of an eccentric cylinder (110, 110a) arranged on either mast mount (84, 148). The cam (110, 110a) can be turned to engage a cavity (78, 78a) in the associated tractor mount (62, 62a) to stop such movement. The mast mounts (84, 148) include a parking stand (36, 36a) and are detachable from the mast (22). The loader can then easily be marketed with or without the locking feature and the parking stand (36, 36a).

Description: This invention relates to a tractor and ground working implement having an implement supporting mast releasably attachable to the front end of the tractor by a forward and rearward mounting structure on either side, the forward structures each comprising a mount on the tractor and a mount engageable therewith on the mast, the tractor mount having an abutment limiting upward movement of the mast mount. Numerous systems exist for attaching a ground working implement in the form of a front end loader to the frame of a tractor. To maintain the versatility of the tractor, the front end loader must be easily and quickly removable from and installable on the tractor. Many of these systems require the operator to leave the tractor cab several times during mounting or dismounting of the loader. Some types of loader mounts utilize loose pins or separate parking stands which must be stored between operations and which may be lost or misplaced. Although numerous systems are available which eliminate separate pins, connectors and parking stands, many of these are complex, bulky or difficult to mount or adjust. The connecting structure is usually made an integral part of the overall loader structure so that a substantial loader redsign effort is necessary to eliminate the optional quick mount or an integral parking stand arrangement. For example, a farmer who maintains his loader on the tractor year round does not want the added expense of a quick mount system with a parking stand. In US-A-3,991,890 a tractor and loader are described with the features referred to in the opening paragraph of the present specification and have a mount system with an integral parking stand. The procedure for attaching the loader to the tractor is somewhat complex. In brief, the tractor is driven against the forward mast mounts so that it abuts them, boom arms of the loader are pivoted until the mast mounts are aligned with supports serving as the tractor mounts, and then the tractor has to be driven forward to cause the rearward mounting structure to become engaged and the mast mounts to become supported on the tractor mounts. The present invention enables this procedure to be simplified. According to the present invention the mast is swingable about the rearward mounting structures upwardly to engage and downwardly to disengage the mast mounts from the tractor mounts, a said mount of each forward structure has a cam which can be turned between a non-operative recessed position enabling movement of the mast and a projecting position, and the other said mount of each forward structure is formed to receive the cam when in the projecting position so as to prevent disengaging downward movement of the mast mount. Thus the movement of the mast is one of swinging about the rearward mounting structure, and the cam can be turned into a projecting position in which it prevents downward disengagement of the mast mounts, and therefore movement of the tractor to slide the mast into full engagement with the tractor is not needed. The cam is preferably remotely operated from the operator's station so the tractor driver does not need to dismount. Embodiments of the invention will now be described with reference to the accompanying diagrammatic drawings in which: Fig. 1 is a side view of a tractor with a loader attached thereto; Fig. 2 is an enlarged perspective view of the forward end of a mast structure on the loader of Fig. 1; Fig. 3 is an enlarged front perspective view of one embodiment of a forward mounting frame, connected to the front end of the tractor; Fig. 4 is a front enlarged view of one embodiment of the invention, partially in section, showing the forward end of a mast arm in the raised position with a cam actuated to latch the mast arm to the tractor frame; Fig. 5 is a view similar to Fig. 4 but showing the cam in the released position with the forward end of the mast arm below the upward-most rocked position; Fig. 6 is a front enlarged view of a second embodiment of the latching structure; Fig. 7 is a view taken substantially along lines 7-7 of Fig. 6; Fig. 8 is a view taken substantially along lines 8-8 of Fig. 6; Fig. 9 is a front view similar to Fig. 6 but showing the cam in the released position with the forward end of the mast arm below the upwardmost rocked position; and Fig. 10 is a view taken substantially along lines 10-10 of Fig. 9; Referring to Fig. 1, there is shown a tractor 10 supported by rear wheels 12 and front wheels 14 for forward movement (F) over the ground. The tractor 10 includes a main frame 16 supporting a front end loader indicated generally at 20. The loader 20 is generally symmetrical about an upright, fore-and-aft extending plane, and includes a mast 22 having rear upright mast posts 24 with lower ends supported on rear support or mounting structure 26 connected to the tractor frame 16. A forwardly extending mast arm 28 is connected at its aft end to the mast post 24 and extends forwardly and downwardly therefrom to a forward end 32. The forward end 32 is releasably secured to the tractor frame 16 by front support or mounting structure 34 to be described in detail below. A parking stand 36 includes side legs 38 extending downwardly from the respective forward mast ends 32 and a bight portion 42 connects the lower ends of the side legs 38. The loader 20 includes a boom 46 having rear boom arms 48 pivotally connected to the upper ends of the mast posts 24. A forward boom arm 52 extends downwardly from each arm 48 to a lower end which pivotally connects a bucket 56 or other earth engaging implement. A lift cylinder 58 is connected between each mast post 24 and the associated rear boom arm 48. A bucket cylinder 60 is connected between the forward end of the boom arm 48 and the bucket 56. The cylinders 58 and 60 are connected to conventional hydraulic circuitry (not shown) for operating the boom 46 and the bucket 56 and for rocking the loader 20 between a mounted position (Fig. 1) and a parked position (not shown) wherein the parking stand 36 rests on the ground. During mounting and dismounting of the loader 20, the lower ends of the mast posts 24 rest on the corresponding rear supports 26 and are pivoted about the rear supports 26 by actuating the cylinder 58 and/or the cylinder 60. Preferably, the rear support 26 is of the type shown and described in our co-pending applications EP-A- 0299377 and 0299378 (filed on the same day). The rear support 26 automatically locks and firmly secures the mast 22 to the tractor frame as the mast is rotated in the clockwise direction (as viewed in Fig. 1) from a parked position wherein the parking stand 36 is in contact with the ground. The front support structure 34 includes a front mounting frame or tractor mount 62 connected to the forward end of the tractor frame 16 by bolts 64. The frame 62 extends outwardly and upwardly from the frame 16 to an upper end supporting a stop member 68 which is connected to the frame by a bolt 70. A pad 72 which angles upwardly in the forward direction is welded to the frame 62 below the stop member 68. An upright plate 74 is connected to the aft end of the pad 72 to define a cavity or cam receiving area indicated generally at 78 extending inwardly from the outermost surface of the mounting frame 62. Locking structure or mast mount 84 which includes the parking stand 36 is connected to the forward end 32 of the mast arm 28 and includes an inwardly opening, channel-shaped member 86. The lower end of the channel-shaped member 86 is connected to the side leg 38 of the parking stand 36. An upright guide member 88 is connected between the sides of the member 86 and is offset above the upper end of the side leg 38 to define an opening 92. The locking structure 84 is connected to the end 32 by a pair of bolts 94 extending through the end 32 and threaded into the guide member 88. The guide member 88 extends upwardly from the bolt area 94 to an upper end which is notched at 96 to define a groove between the guide member 88 and the inside surface of the mast end 32. The lower end of the stop member 68 includes complementary structure for receiving the grooved end of the guide member 88 as the mast 22 is rotated upwardly about the rear supports 26. The bottom surface 98 of the stop member 68 angles upwardly at an approximately 45 degree angle from the outside edge to a vertical wall 102 which defines a notch 106 between the stop member 68 and the outermost surface of the frame 62. As the mast 22 is raised, the angled surface 98 guides the projection at the top of the guide member 88 into the notch 106. The guide member 88 then bottoms against the stop member 68 as the mast 22 reaches the mounted position. The guide member 88 and stop member 68 cooperate to prevent lateral movement and vertical movement of the mast arm 28. To lock the mast arm (28) to the tractor frame and to prevent downward and forward movement of the mast arm with respect to the frame, a wedge operated cam 110 is pivotally secured to the channel-shaped member 86 adjacent the opening 92 for rocking into the cavity or cam-receiving area 78 (Fig. 4). A wedge 112 is slidably mounted against the bight portion of the member 86 for urging the cam 110 into the cavity 78 and for maintaining the cam within the cavity while the loader 20 is mounted on the tractor 10. As shown in Figs. 4 and 5, the cam 110 is a cylindrical member and is pivotally connected to the sides of the channel-shaped member 86 by a pivot pin 116 at a location offset above the cylindrical axis of the cam 110. In the unlocked position (Fig. 5) the cam 110 is generally contained within the channel-shaped member 86 to permit free movement of the forward end 32 of the mast arm to and from the mounted position. In the unlocked position, the cam 110 is offset slightly from the bight portion of the channel-shaped member 86. The wedge 112 is slidably secured against the bight portion by a bracket 118 and includes a lower tapered end 122 adapted to urge the cam 110 inwardly as the wedge 112 is moved downwardly (Fig. 4). The upper end of the wedge 112 is secured to a cable 126 which in turn is supported at one end by a bracket 128 connected to the upper end of the member 86. The cable 126 is enclosed in a sheath 132 and extends upwardly and rearwardly along the mast 22 to a location adjacent an operator station 134 on the tractor 10. A knob 136 is connected to the operator end of the cable 126 so that the cable may be extended and retracted to rotate the cam 110 between its locked and unlocked positions. A knob lock 137 (Fig. 2) prevents movement of the cable to lock the wedge 112 against upward movement during loader operations. A mechanical linkage may be substituted for the cable 126 to provide remote control of the wedge 112. As best seen in Figs. 2, 4 and 5, a substantial portion of the locking structure 84 is part of an assembly common with the parking stand 36. Therefore, if a purchaser of a loader 20 does not wish to have the parking stand feature and the latch feature, the forward end 32 of the mast arm 28 may be connected directly to front support structure by inserting bolts through the forward end 32 (at the location where the bolts 94 are located as shown in Fig. 2) and through corresponding holes in a simplified mounting frame (not shown) connected to the forward end of the tractor frame 16. In operation, assuming that the loader 20 is supported on the parking stand 36 and the bucket 56 with the mast posts 24 raised above the ground, the tractor 10 is first driven forwardly until the rear support 26 is below the mast post 24. The cylinders 58 are then operated to lower the posts 24 onto the supports 26. Continued retraction of the cylinders 58 rotates the mast arms 28 upwardly and the locking structure 84 approaches the mounting frame 62 (Fig. 5). The wedge 112 is in the retracted position to permit free movement of the structure 84 relative to the frame 62. Continued retraction of the cylinders 58 causes the guide member 88 to move against the lower surface 98 of the stop member 68. The upper projection of the guide member 88 is thereby guided into the notch 106, and the stop member 68 prevents further upward rotation of the mast arms 28 once the cam 110 is located adjacent the cavity 78. At this point, the operator pushes the knob 136 to slide the wedge 112 against the cam 110, which rotates the cam in the clockwise direction (Fig. 4) into the cavity to lock the mast arm in position. Therefore, once the hydraulic lines are connected to the loader 20, the operator can attach the loader without leaving his tractor seat. To detach the loader from the tractor, the operator pulls back on the knob 136 to slide the wedge 112 away from the cam 110. The cam is therefore free to rotate about the pivot 116 away from the cavity 78 thereby permitting the locking structure 84 to move downwardly with respect to the front mounting frame 62. The operator extends the cylinders 58 to move the parking stand 36 downwardly into engagement with the ground. Continued extension of the cylinders lifts the mast posts 24 from the respective rear supports 26 so that the loader 20 rests on the bucket 56 and the parking stand 36. The operator then disconnects the hydraulic lines and backs the tractor 10 away from the loader 20. In the embodiment shown in Figs. 6-10, the front support structure 34a includes a guide member 88a connected to the front mounting frame 62a. Mating bracket structure 148 which is connected to the forward end 32a by a bolt 150 includes a parking stand 36a which has side legs 38a. A bight portion (not shown) connects the lower ends of the side legs 38a. Each side leg 38a angles outwardly at location 152 and extends upwardly at 154 to define the outermost wall of the mounting structure 148. A plate 156 is welded to the location 152 and to the outer wall 154. An angle 158 is welded to the aft edge of the wall 154 and extends inwardly therefrom to a forwardly directed flange 160 (Fig. 7) which is slidably received within a notch 164 located in the member 88a adjacent the outer face of the mounting frame 62a. A cylindrically shaped cam 110a is journalled for rotation on a pin 116a which extends through the plate 156 and the angle 158 (Fig. 7). A sleeve 170 is positioned over the pin 116a between the angle 158 and the cam 110a. A cam receiving area or cavity 78a is located in the guide member 88a. A cable bracket 128a is connected to the upper end of the wall 154 and supports a cable 126a which is routed along the loader to a position adjacent the operator's station 134 as shown in Fig. 1. A wedge 112a is slidably mounted within the bracket structure 148 adjacent the inside surface of the wall 154. The wedge 112a is connected to the cable 126a for movement between a locking position (Fig. 6) wherein the cam 110a is urged into the cavity 78a and a release position (Fig. 9) wherein the wedge 112a is slid upwardly by the cable 126a to a location wherein the cam 110a is free to rotate outwardly toward the wall 154 away from the cavity 78a. A U-shaped spring clip 174 includes an upper bight portion located above the top surface of the wedge 112a. The lower portion of the clip 174 is bent inwardly toward the cam 110a and includes projections 176 which are inserted into corresponding holes in the cam 110a which are offset downwardly and outwardly from the axis of the pin 116a. As the wedge 112a is lifted (Fig. 9) the top of the wedge contacts the bight portion on the clip 174 and urges the clip upwardly to pull the cam 110a toward the wall 154. The wedge 112a is free to slide downwardly from the bight portion of the clip 174 when the wedge is moved toward the locking position (Fig. 6). The member 88a includes a stop indicated generally at 180 located above and to one side of the cavity 78a. A threaded projection 182 extends outwardly from the member 88a and an adjusting bolt 184 is threaded through the projection. A locking nut 186 is tightened against the projection 182 to secure the bolt 184 in the preselected adjusted position. As the forward end 32a of the mast is raised into position, the lower end of the bolt 184 contacts the bracket structure 148 to prevent upward movement of the mast beyond the location wherein the cam 110a is aligned with the cavity 78a (Fig. 6). In operation, the mast 22 is rotated about the rear supports 26. As the forward end of the mast 32a approaches the mounted position, the flange 160 of the angle 158 is guided into the notch 164. The operator continues to raise the forward end 32a until the bracket structure 148 contacts the stop 180. The operator from his tractor seat then moves the knob on the operator end of the cable 126a to force the wedge 112a against the cam 110a. The wedge 112a forces the cam 110a into the cavity 78a (Fig. 6) to lock the forward end 32a of the mast in position on the tractor frame 16. To remove the loader from the tractor frame, the operator pulls the knob of the cable 126a to slide the wedge 112a upwardly away from the cam 110a (Fig. 9). The spring clip 174 pulls the cam 110a from the cavity 78a (Fig. 9) so that the forward end of the mast 32a is free to move downwardly away from the member 88a. As best seen in Figs. 6 and 8, the mating bracket structure 148 and the parking stand 36a may be removed from the forward end 32a simply by removing the bolt 150, which connects the bracket structure 148 to a cylindrical member 190 welded to the bottom of the end 32a. Therefore, if a farmer does not wish to have the parking stand and remotely operable locking feature, he may connect the end 32a directly to a simplified bracket (not shown) mounted on the tractor frame 16.

Claims: 1. A tractor and ground working implement having an implement supporting mast (22) releasably attachable to the front end of the tractor (10) by a forward and rearward mounting structure (34, 26, 34a) on either side, the forward structures (34, 34a) each comprising a mount (62, 62a) on the tractor (10) and a mount (84, 148) engageable therewith on the mast (22), the tractor mount (62, 62a) having an abutment (68, 180) limiting upward movement of the mast mount (84, 148) characterized in that the mast (22) is swingable about the rearward mounting structures (26) upwardly to engage and downwardly to disengage the mast mounts (84, 148) from the tractor mounts (62, 62a), a said mount (84, 148) of each forward structure (34, 34a) has a cam (110, 110a) which can be turned between a non-operative recessed position enabling movement of the mast (22) and a projecting position, and the other said mount (62, 62a) of each forward structure is formed to receive the cam (110, 110a) when in the projecting position so as to prevent disengaging downward movement of the mast mount (84, 148). 2. A tractor and ground working implement according to claim 1 characterized in that the said mount which has the cam (110, 110a) is the mast mount (84, 148). 3. A tractor and ground working implement according to claim 1 or 2 characterized in that the cam (110, 110a) is operatively connected to a remote control (126, 132, 136, 126a) workable by an operator of the tractor (10). 4. A tractor and ground working implement according to claim 3 characterized in that the remote control (126, 132, 136) is operatively connected to the cam (110) by a wedge (112) movable by the control (126, 132, 136) against the cam (110) to turn it. 5. A tractor and ground working implement according to claim 3 or 4 characterized in that the remote control comprises a cable (126). 6. A tractor and ground working implement according to claims 3 and 5 characterized in that the cable (126a) is connected to the cam (110a) by a spring clip (174). 7. A tractor and ground working implement according to any preceding claim characterized in that the cam comprises a cylindrical member (110, 110a) pivotable about an axis offset from the axis of the cylinder. 8. A tractor and ground working implement according to any preceding claim characterized in that the mast mounts (84, 148) are removably attachable to the mast (22). 9. A tractor and ground working implement according to claim 8 characterized in that the mast mounts (84, 148) include a parking stand (36, 36a) and are removably attachable as a unit to the mast (22). 10. A tractor and ground working implement according to any preceding claim in which the tractor mounts (62, 62a) have outwardly facing guide surfaces and the mast mounts (84, 148) have corresponding inwardly facing guide surfaces in contact therewith when the mounts (62, 62a, 84, 148) are in engagement, so as to prevent lateral movement of the mast mounts (84, 148). 11. A tractor and ground working implement according to any preceding claim characterized in that the cam (110) when in the projecting position is sandwiched between the two mounts (62, 84).

Inventors: FRIESEN, HENRY, TISCHLER, FREDRICK GORGE
Applicants: DEERE & COMPANY
Application year: 1988
Main classification: E02F3
IPC codes: E02F3