WO2007137350A1

WO2007137350A1 - Automatic locking device

Info

Publication number: WO2007137350A1
Application number: PCT/AU2007/000744
Authority: WO
Inventors: Daniel Webb; Tim Smith; Colin O'shaughnessy; Craig Healey; John Healey
Original assignee: Challenge Implements Holdings Pty Limited
Priority date: 2006-05-31
Filing date: 2007-05-29
Publication date: 2007-12-06

Abstract

An automatic locking device for attaching a first member to a second member, said device including: a receiving structure provided on said second member, said receiving structure including a first angled surface; a mounting structure provided on said first member and adapted to engage said receiving structure for releasably attaching the first member to the second member; said mounting structure including a second angled surface; said second angled surface being adapted to cooperate with said first angled surface; pivoting engagement means for pivotably engaging the mounting structure and the receiving structure, said engagement means having a pivot axis for providing pivoting movement of the mounting structure and the receiving structure between an engaged position and a disengaged position; cam means for releasably locking the mounting structure and the receiving structure in said engaged position, said cam means being movable between a locked condition and an unlocked condition; latching means for releasably locking said cam means in said locked condition, said latching means being operably connected to said cam means, said latching means being movable between a latching position and a release position, said latching means being biased toward the latching position; whereby engagement of said first member and said second member will cause the latching means to move said cam means to said locked condition.

Description

Automatic Locking Device

Field of the invention

[001] The present invention relates generally to a device for releasably attaching a first member to a second member. More particularly, the present invention relates to a device for releasably attaching a front loader to a vehicle frame or an implement to a front or rear end loader or other vehicular attachment.

Background of the invention

[002] Front loaders, also called front end loaders, bucket loaders, scoop loaders etc, are well known in the art. Although the design of front loaders can significantly differ, certain components are common to all front loaders. Thus one of the main components of a front loader is one or more movable arms adapted to lift and move material.

[003] To this end, a front loader is typically provided with a tilting bucket connected to the one or more movable arms. The bucket can be replaced with other devices or tools. For example, many front loaders can mount forks to lift heavy pallets or shipping containers.

[004] Any reference herein to known prior art does not, unless the contrary indication appears, constitute an admission that such prior art is commonly known by those skilled in the art to which the invention relates, at the priority date of this application.

Summary of the invention

[005] The present invention provides an automatic locking device for attaching a first member to a second member, said device including: a receiving structure provided on said second member, said receiving structure including a first angled surface; a mounting structure provided on said first member and adapted to engage said receiving structure for releasably attaching the first member to the second member; said mounting structure including a second angled surface; said second angled surface being adapted to cooperate with said first angled surface; pivoting engagement means for pivotably engaging the mounting structure and the receiving structure, said engagement means having a pivot axis for providing pivoting movement of the mounting structure and the receiving structure between an engaged position and a disengaged position; cam means for releasably locking the mounting structure and the receiving structure in said engaged position, said cam means being movable between a locked condition and an unlocked condition; latching means for releasably locking said cam means in said locked condition, said latching means being operably connected to said cam means, said latching means being movable between a latching position and a release position, said latching means being biased toward the latching position; whereby engagement of said first member and said second member will cause the latching means to move said cam means to said locked condition.

[006] Said latching means can include a lock member.

[007] The mounting structure can further include engagement means; said engagement means being adapted to releasably engage said lock member.

[008] The arrangement can be such that during pivoting movement of said mounting structure and the receiving structure to their engaged position, the first angled surface contacts the second angled surface causing movement of the biased latching means to its latching position wherein the cam means releasably couples the mounting structure to the receiving structure, and wherein the lock member engages the engagement means provided on the mounting structure thereby releasably locking the cam means in its locked condition; and whereafter movement of the latch means to its release position unlocks the cam means and allows pivoting movement between the mounting structure and the receiving structure from their engaged position to their disengaged position.

[009] The cam means can include an off-centre cam.

[010] The cam means can include means for positive engagement between the mounting structure and the receiving structure.

[011] The receiving structure can include at least one recess, said recess being adapted to engage a complementary member of said mounting structure.

[012] The recess can include a U-shaped opening.

[013] The recess can be provided with a bearing, said bearing being configured to receive a complementary member provided on the mounting structure.

[014] The complementary member can include pin means. [015] The complementary member can include cam means.

[016] The receiving structure can include a concave portion upon a corresponding transverse pin of the mounting structure will be resting when the receiving structure and the mounting structure are in an engaged position.

[017] The receiving structure can further include a centering guide for aiding an operator in positioning the receiving structure in a predetermined position laterally with respect to the mounting structure. [018] The receiving structure can include a plate and a tab member protruding from a side of the plate in a direction generally perpendicular to the plate, said tab member providing said first angled surface.

[019] The first angular surface can be configured to align with and impinge against said second angular surface provided on the mounting structure to thereby automatically trigger locking action.

[020] The tab member can be adapted to engage a corresponding recess provided on the mounting structure.

[021] The mounting structure can include a first and a second mounting plate, said plates being disposed in a spaced parallel relationship.

[022] The mounting structure can further include a connecting element in the form of a transverse mounting pin, said pin extending between said plates.

[023] The pivoting engagement means can include a transversely mounted pin provided on said mounting structure.

[024] Each side plate can be provided with an aperture extending transversely therethrough for rotatably receiving a cam shaft.

[025] The locking device can include torsion spring means for normally biasing said latching means toward the latching position.

[026] The torsion spring means can be tensioned between a mounting plate and said cam means.

[027] The latching means can be mounted on said cam shaft for movement toward and away from said mounting plate.

[028] The locking device can include compression spring means for normally biasing said latching means toward said mounting plate.

[029] The compression spring means can be disposed between the latching means and a handle provided on said mounting means.

[030] The locking device can include compression spring means for normally biasing said latching means toward the latching position.

[031] The locking device can include compression spring means for normally biasing said latching means toward the release position. [032] The locking device can include compression spring means for normally biasing said lock member toward a locked position in registry with either an aperture or a recess provided on said mounting plate.

[033] The engagement means can include an aperture formed in said mounting plate, said aperture being adapted to releasably engage said lock member.

[034] The engagement means can include a recess formed in said mounting plate, said recess being adapted to releasably engage said lock member.

[035] The lock member can include said second angular surface.

[036] The automatic locking device can further include a release handle, said handle being operative to move said latching means to said release position.

[037] The release handle can be attached to the cam shaft to assist in rotating said latching means against said torsion spring means.

[038] The handle can be mounted on said cam shaft for movement toward and away from said latching means.

[039] The latching means can include a projection extending in a direction generally perpendicular to the release handle and said handle can include a complementary aperture, said complementary aperture being adapted to receive said projection, the arrangement being such that when the mounting structure and the receiving structure are in a locked condition, a compression spring disposed between the latching means and the release handle biases the release handle outwardly thereby disengaging the projection and the complementary aperture; and whereafter the lock member is moved to an unlatched position by an operator, the projection can be positioned in registry with the complementary aperture to thereby enable the operation of the release handle.

[040] The handle and the latching means can be integrally formed.

[041] The handle can provide a portion for grasping by a user on either side of its centre of rotation.

[042] The handle and the latching means are mounted on the cam shaft so as to be able to pivot laterally with respect to the rotation axis of said cam shaft.

[043] A recess can be provided in the handle to allow said handle to pivot with respect to said cam shaft. [044] The automatic locking device can further include a flag member for indicating that the cam means is in said locked condition.

[045] The automatic locking device can further include a flag member for indicating that the cam means is in said unlocked condition.

[046] A wear member can be provided on a surface of second member for a portion of said latch member to make sliding contact.

[047] The wear member can include an indication of the locking or unlocking direction of rotation of said latching means.

[048] The present invention also provides a method for releasably attaching a first member to a second member, said second member being provided with a receiving structure, said first member being provided with a mounting structure, said method including the steps of: pivotably engaging the mounting structure and the receiving structure, and using cam means for releasably locking the mounting structure and the receiving structure in an engaged position.

[049] The present invention further provides a method for releasably attaching a first member to a second member, said method including the steps of: providing a receiving structure on said second member; providing a mounting structure on said first member; providing pivoting engagement means for pivotably engaging the mounting structure and the receiving structure, said engagement means having a pivot axis for providing pivoting movement of the mounting structure and the receiving structure between an engaged position and a disengaged position; providing cam means for releasably locking the mounting structure and the receiving structure in said engaged position; and triggering said locking action by actuator means on said receiving structure and or said mounting structure.

[050] The cam means can include an off-centre cam.

[051] The cam means can include means for positive engagement between the mounting structure and the receiving structure.

[052] The method can further include actuator means provided on said receiving structure and or said mounting structure, said actuator means adapted to trigger said locking action.

[053] In the method or device described above the first member can be a vehicular attachment means, and said second member can be a vehicle. Alternatively the first member can be an implement, and said second member can be a vehicular attachment means. [054] The vehicular attachment means mentioned in the previous paragraph can be a front end loader, a rear end loader, a side loader or any appropriate means which needs attachment to a vehicle or to which an implement has to be attached.

Brief description of the drawings

[055] An embodiment or embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[056] Figure 1 is a side elevation view of a front loader attached to a vehicle frame by an automatic locking device;

[057] Figure 2 is a schematic cross-sectional view of the automatic locking device of Figure 1;

[058] Figure 3 is a fragmentary side view of a bottom post of the automatic locking device of Figure 1;

[059] Figure 4 is a fragmentary perspective view of the bottom post of Figure 3;

[060] Figure 5 is a perspective view of the automatic locking device of Figure 1 shown in an unlocked condition;

[061] Figure 6 is a perspective view of the automatic locking device of Figure 1 shown in a locked condition;

[062] Figure 7 is a rear view of the automatic locking device of Figure 6;

[063] Figure 8 is a fragmentary perspective view of a top post of the automatic locking device of Figure 1, showing a lock member in an unlocked condition;

[064] Figure 9 is a fragmentary perspective view of the bottom portion of the top post of Figure 8, showing the lock member in a locked condition;

[065] Figure 10 is a perspective view of a lock indicator of the automatic locking device of Figure 1, showing the locking device in an unlocked condition;

[066] Figure 11 is a perspective view of the lock indicator of Figure 10, showing the locking device in a locked position;

[067] Figure 12 illustrates the manner in which an angular tab of the bottom post impinges on the lock member of the top post when the front loader of Figure 1 is about to be attached to a vehicle frame; [068] Figure 13 illustrates pivoting engagement of the top post and the bottom post of the locking device of Figure 1 ;

[069] Figures 14 is a fragmentary perspective front view of an alternative bottom post;

[070] Figure 15 is fragmentary perspective rear view of the bottom post of Figure 14;

[071 ] Figure 16 is a side view of a casting of the bottom post of Figure 14;

[072] Figure 17 is a front view of the casting of Figurelό;

[073] Figure 18 is an underneath perspective view of a modified automatic locking device;

[074] Figure 19 is a perspective view of the device of figure 18 in a locked condition; and

[075] Figure 20 is a sectioned perspective view of the device of figures 18 and 19 in an unlocked condition.

Detailed description of the embodiment or embodiments

[076] Illustrated in Figure 1 is a front loader 10 removably attached to a vehicle frame

(not shown). To this end, the vehicle frame is provided with a post support member 12 projecting outwardly of the vehicle frame, and a front end loader bottom post 14 is erected on the support member 12.

[077] As illustrated in figures 1 and 2, it can be seen that attached to the front end loader bottom post 14 is a front end loader top post 16, in a releasable or removable manner. The top post 16 includes three pivot pins: a lift cylinder pivot pin 26, a boom pivot pin 28, and a link pivot pin 30.

[078] Thus, pivotably extending from pivot 28 at an intermediate forward location of top post 16 is a boom 18. A lift cylinder 22 extends between pivot pin 26 at the lower forward end top post 16 and the boom 18. Extending between the link pivot 30 and a generally triangular plate 25 (which is pivotally attached by its lower pivot as is best seen in Figurel) is a linkage 32. An implement cylinder 24 extends between the pivoted distal end 20 of the boom 18 and the triangular plate 25. An implement (not illustrated) can be attached to the pivoted distal end 20 of the boom 18.

[079] The pivots 26, 28 and 30 preferably are of hollow construction to allow for greasing nipples and passage to conduct grease to location where such grease will be needed for the protection of wear surfaces. Further these pivots preferably have a D-shaped end to be received in D-shaped apertures in side plate 66.2 (see figure 12) to prevent rotation of these pivots in use.. Figure [080] Referring to Figures 3 and 4, the bottom post 14 includes a plate member 34 having a plurality of recesses 36, 38, 40, and 52 formed therein.

[081] The recess 36 is provided with a U-shaped bearing 42. The bearing 42 forms an alignment slot dimensioned and configured to receive a corresponding mounting pin 44 on the top post 16.

[082] The recess 38 is sized and shaped to receive a centering guide 46 which is subsequently welded therein for aiding an operator in positioning the bottom post 14 in a predetermined position laterally with respect to the top post 16.

[083] The lock recess 40 includes a concave portion 41 and a planar surface 43.

Similarly to recess 36, the lock recess 40 is provided with a bearing 48. The bearing 48 is dimensioned and configured to receive a cam pin 50 of the top post 16.

[084] As best illustrated in Figures 2 to 4, the bottom post 14 has a shallow bearing recess 52 against which a corresponding bearing pin 54 of the top post 16 will be resting when the top post 16 and the bottom post 14 are assembled and locked together.

[085] Protruding from a side of the bottom post 14 in a direction perpendicular thereto is an angular tab 56. The angular tab 56 includes upper and lower generally horizontal surfaces 60 and an actuation surface 57. The purpose of the angular tab 56 is twofold. First, the angular tab 56 includes the vertical actuation surface 57 (which is oriented at an angle approximately 45 degrees to the side face of the post 14) configured to align with and impinge against a lock member 62 (see figure 5) to automatically disengage the lock member 62 from a slot 58, during mounting of the top post 16 to the bottom post 14. As a result, the cam pin 50 assumes its locked condition. Secondly, the tab 56 is adapted to engage a corresponding slot 58 in the to post 16 thereby providing a surface against which the lock member 62 bears when the top post 16 and the bottom post 14 are about to be disengaged.

[086] Illustrated in Figs. 5 to 9 and 12 is the top post 16 with a locking device 64 attached thereto.

[087] The top post 16 includes a pair of spaced side plates 66.1 and 66.2. Extending between the side plates 66.1 and 66.2 are two connecting elements, with the top connecting elements being the mounting pin 44 and the bottom element being the bearing pin 54, each pin having a horizontal axis. The pins 44 and 54 can be welded or otherwise fixed to the side plates 66.1 and 66.2. As mentioned previously in this specification, the mounting pin 44 and the bearing pin 54 are adapted to releasably engage the slot 36 and the concave surface 52 respectively to thereby form a complementary portion of the top post 16 to which the bottom post 14 can be connected.

[088] As best shown in Figure 7, the side plates 66.1 and 66.2 are spaced from each other by a greater distance than the width of the centering guide 46 so that the guide 46 will centre the top post 14 as the posts 14 and 16 are brought together.

[089] Each side plate 66.1 and 66.2 is provided with an aperture (not shown) extending transversely therethrough for rotatably receiving a stepped shaft 68. The shaft 68 includes the cam pin 50 and an enlarged diameter portion 70. The enlarged diameter portion 70 carries a torsion spring 72. The cam pin 50 is in the form of an off-centre cam having a planar surface 51. When rotated in the recess 41, the outer peripheral surface of the off-centre cam provides means for positive engagement between the posts 14 and 16 whereby the posts 14 and 16 will not readily rattle or move with respect to each other. It will be appreciated by those skilled in the art that other suitable shafts could be used as a substitute to an off centre cam, however, such alternatives may not restrain the posts 14 and 16 with respect to each other as effectively as an off-centre cam.

[090] The torsion spring 72 is tensioned between the side plate 66.1 and the enlarged diameter portion 70 of the shaft 68 so that it rotatably urges or biases the cam pin 50 towards a locked condition wherein the passage of the cam pin 50 to or from the lock recess 40 is blocked, as is illustrated in Figure 2, thereby locking the cam pin 50 in the lock recess 40.

[091] As illustrated in Figure 9, when the top post 16 and the bottom post 14 are in their locked condition, the lock member 62 of a latch 73 engages an aperture 74 formed in the side plate 66.1 of the top post 16. As shown in Figures 10 and 11, an arrow-shaped flag member 84 attached to the shaft 68, and located on the outside surface of plate 66.2, indicates that the cam . pin 50 is in a locked condition, by pointing to an "open lock" shaped silhouetted aperture 90.

[092] The latch 73 is mounted to the shaft 68 so that as the latch 73 rotates so does the cam pin 50. To effect this the latch 73 has a shaped aperture to receive the complementary shape of the shaft 68 passing through the latch 73. The latch 73 also has a sliding pivot leg 73.1, which will slide over the surface of the plate 66.1. The pivot leg 73.1 is utilised to allow for a more positive movement of the lock member 62 into the slot 58 and aperture 74, under the bias provided by the compression spring 78. The pivot leg 73.1 also assists by providing a fulcrum or pivot when an operator needs to move the lock member 62 out of aperture 74. The latch 73 is moveable to an unlocked condition by means of a release handle 76 coupled to the shaft 68 and to the locked condition by the torsion spring 72. [093] Protruding from the latch 73 in a horizontal direction is a projection 80 adapted to be received in a complementary aperture 82 formed in the release handle 76. When the top post 16 and the bottom post 14 are in a locked condition, a compression spring 78 disposed between the latch 73 and the release handle 76 biases the latch 73 away from the release handle 76. The release handle 76 is rotatably secured to the end of the shaft 68.

[094] The lock member 62 is disengaged from the aperture 74 by an operator pulling the lock member 62 out therefrom, and simultaneously the projection 80 is received in the aperture 82 by pushing the release handle 76 against the bias of the compression spring 78. This enables the release handle 76 to be able to motivate the latch 73 so that the cam pin 50 can be then driven to an unlocked condition by rotating the release handle 76 clockwise in Figure 2, 5, 6 or 9. As illustrated in Figure 10, the flag member 84 indicates that the cam pin 50 and shaft 68 are in an unlocked position.

[095] The automatic locking device described above operates as follows. The automatic locking device is mounted to the top post 16, with the lock member 62 being in an unlocked condition as shown in Figure 8 (referred to as "the release position").

[096] In attaching the top post 16 to the bottom post 14, the boom 18 of the front loader

10 and the top post 16 attached thereto are first positioned so that the mounting pin 44 of the top post 16 is positioned in the complementary recess 42 of the bottom post 16. The top post 16 is then pivoted relative to the bottom post 14 so that the pins 50 and 54 engage the respective recesses 41 and 52. To facilitate the lateral alignment of the top and bottom posts, the operator uses the centering tab 46.

[097] The pivotal movement of the posts 14 and 16 is achieved as shown in Figs. 12 and

13. The top post 16 and the bottom post 14 are then engaged so as to allow pivoting movement about a pivot axis defined by the transverse pin 44. The weight of the top post 16 causes the top post 16 to swing about the pin 44 toward the bottom post 14.

[098] During this pivoting movement of the top post 16 relative to the bottom post 14, the front surface of the angular tab 56 of the bottom post 14 contacts the lock member 62 causing the latter to move outwardly relative to the side plate 66.1 This movement disengages the lock member 62 from the slot 58.

[099] Once clear of the side plate 66.1, then under the action of the torsion spring 72, the spring loaded off-centre cam pin 50 pivots counter clockwise in Figure 2 toward its locked condition till the latch 73 is brought into a locking engagement with the aperture 74 in the side plate 66.1 (referred to as "the latching position"), as is shown in Figure2. [0100] The lock member 62 of the latch 73 is pushed by the compression spring 78 into the aperture 74 thereby preventing the latch 73 from rotating past its latching position during the counter clockwise movement of the lock member 62 over the side plate 66.1. As a result, the cam pin 50 cannot be turned to an unlocked position unless the operator pulls the lock member 62 out of the aperture 74 by means of the latch 73, against the biasing force exerted by the compression spring 78, and turns the cam pin 50 to an unlocked position. During use, the aperture 74 also prevents the latch 73 moving to the unlocked or partially locked condition

[0101] The flag member 84 indicates that the automatic locking device is in a locked position by pointing to a lock silhouetted aperture 92, as is shown in Figure 11.

[0102] In detaching the top post 16 from the bottom post 14, the operator pulls the lock member 62 out of the aperture 74. When the lock member 62 is disengaged from the aperture 74 by the operator, the projection 80 is pushed into the aperture 82, and the operation of the release handle 76 is thereby enabled. The cam pin 50 can be then driven to an unlocked condition by rotating the release handle 76 clockwise till the compression spring 78 pushes the lock member 62 onto the angular tab 56 located in the slot 58 as shown in Figure 5. This is done preparatory to the posts 14 and 16 being separated.

[0103] As illustrated in Figure 10, the flag member 84 indicates that the cam pin 50 is in an unlocked condition, and the top post 16 and the bottom post 14 can be disengaged. When the top post 16 is fully detached, the lock member 62 is moved to its release position, i.e. the position where it bears against an upper surface of the slot 58 and is locked against rotation by the action of the torsion spring 72, as is illustrated in Figure 8. Activating the lift cylinder 22 moves the pin 54 and the cam shaft 50 out of the bottom post 16.

[0104] Illustrated in Figures 14 to 17 is a modified bottom post 140. The construction of the bottom post 140 is similar to the bottom post 14, and like parts having like functions have been like numbered.

[0105] The bottom post 140 is a two-part construction including a casting 100 welded to a plate member 110.

[0106] Similarly to the bottom post of Figs. 1 to 7 and Figs. 10 to 13, the casting 100 includes a plate member 34 having a plurality of recesses 36, 40, and 52 formed therein.

[0107] The recess 36 is provided with a bearing 42 dimensioned and configured to receive a corresponding mounting pin 44 on the top post 16. [0108] The lock recess 40 includes a planar surface 43 and a concave portion 41 provided with a bearing 48 dimensioned and configured to receive a cam pin 50 of the top post 16.

[0109] The casting 100 has a shallow bearing recess 52 against which a corresponding bearing pin 54 of the top post 16 will rest when the top post 16 and the bottom post 140 are assembled and locked together.

[0110] The casting 100 further includes an angular tab 56 and a centering guide 460, the functions of which are identical to those described earlier in this specification.

[0111] The two-part construction of the bottom post 140 provides a more efficient means, both in speed and cost, to manufacture a bottom post as an alternative to the bottom post 14. hi addition, the bottom locating pin 54 has a bigger bearing area 52 (from 32mm wide to 70mm). Also because the casting is machined the mating areas will be exact fits which means greater load bearing area on both of the locating pins 44, 54 and the cam pin 50.

[0112] Illustrated in figures 18 to 20 is a modified locking device similar to that illustrated in figures 5 to 12, with the differences being described in detail below. As there are many similarities like parts in the device of figures 18 to 20 are like numbered to the device of figures 5 to 12.

[0113] The handle 76 and the latch 73 are integrally cast in the device of figures 18 to 20, with the handle 76 being joined to the latch 73 by a cylindrical housing 76.2, having a tapered recess 76.3 therein, as is best illustrated in figure 20, which is closed off by a polymeric cap 79 (see figure 18) having upper and lower lugs 79.1 and 79.2 which engage recesses 76.8 and 76.9 in the housing 76.2. The handle 76 is opposed by an opposite handle 76.1, which allows an operator to use two hands to operate the device.

[0114] The recess 76.3 is tapered and houses the compression spring 78, as well as a washer 78.1 and machine screw 78.2 which secures the washer 78.1 to the cam pin 50, and compresses the compression spring between the inside face of the washer 78.1 and an inboard rim of the recess 76.3. As the end of the cam pin 50 does not translate relative to the plates 66.1 and 66.2, the compression spring 78 biases the latch 73, so as to force the lock member 62 into slot 58. As the latch 73 has a sliding pivot leg 73.1 the housing 76.2 will effectively rotate laterally relative to the cam pin 50, and this rotation will move the outer tip of the handle 76.1 towards the plate 66.1, while the outer tip of handle 76 will move away from plate 66.1. This rotation is allowed by means of the tapered recess 76.3, which will allow rotation until such time as the compression spring 78 has fully compressed on one side, thus preventing any further rotation in that direction, or alternatively until the side wall of the recess 76.3 engages the sides of the coils of the compression spring 78. As a further alternative a larger washer 78.1 could be used to provide a stop to limit this rotation.

[0115] While a tapered recess 76.3 is illustrated and preferred, a sufficiently large enough cylindrical recess will operate satisfactorily as well, but this will generally result in a greater cost in both extra weight and expense.

[0116] Through the base of the housing 76.2 is an aperture 76.4, of which only the top edge is visible in figure 20. The aperture 76.4 is preferably of the same shape as the cam pin 50 and its planar surface 51, but it can be of a complementary or matching shape, but needs to be able to engage the cam pin 50 so as to be able to rotate it.

[0117] As with the device of figures 5 to 12, to move the device of figures 18 to 20 from the unlocked to the locked condition requires the engagement of the device with a bottom post 14, which will force lock member 62 out of slot 58, and then the anti clockwise bias of torsion spring 72, will automatically move the lock member 62 into the aperture 74, which is best viewed in figure 18.

[0118] To unlock the locking device and to arm it ready for the next time the top post 16 and bottom post 14 are combined, the operator will place one hand on the handle 76 and another on handle 76.1, and this time the handle 76.1 will move away from the side plate 66.1, while handle 76 will move towards plate 66.1. This angular displacement or rotation is allowed by the provision of the tapered recess 76.3 in the housing 76.2.

[0119] Unlike the device of figures 5 to 12, the device of figures 18 to 20 does not require an operator to manually grab or hook the latch 73 to bring the lock member 62 out of the aperture 74. This tends to make the device of figures 18 to 20 safer and easier to use, and further, the latch 73 below the lock member 62 has an extensive surface area which allows the latch 73 to act as a finger or thumb guard, thus further protecting the operator.

[0120] A further difference between the devices of figs 5 to 12 and figures 18 to 20 is that the sliding pivot leg 73.1, as is best visible in figure 18, is provided with a larger elongated contact surface to make contact with a wear plate 77 which is described below. The contact surface being flat or parallel to the wear plate 77, means that the handles 76 and 76.1 will be braced against rotation around the longitudinal axis of those handles. This means that an operator will effectively be only able to rotate the handles 76 and 76.1 around the rotation axis of the cam pin 50, and to rotate the handles laterally of the cam pin 50 towards or away from the plate 66.1. [0121] Another difference is the fitting of the polymeric wear plate 77 having a wear surface 77.1, over which the rotating pivot point 73.1 and the lock member 62 can move. The wear plate 77 includes indicia or cut outs 77.2 in an "unlocked lock" silhouette and 77.3 in a "locked lock" silhouette, with a double headed arrow 77.4 to indicate the respective lock and unlock directions.

[0122] The wear plate 77 can be attached to the outboard face of the side plate 66.1, by any appropriate method including adhering, or self tapping screws or as in the present case, a series of four lugs 77.6 which in the case of the one in figure 18, sits flush with the edge of the aperture 74, while another sits flush with the edge 58.1 of slot 58. In order to sit flush, recesses of the thickness of the lugs 77.6 are cut into the respective edges when the slot 58 and aperture 74 are formed.

[0123] Further, in the vicinity of respectively diametrically opposed locations to the edges of slot 58 and the aperture 74, two lugs pass through openings formed in the plate 66.2. Each of the lugs 77.6 extend across the width of the plate 66.2 as illustrated in figure 18 and engage, by means of a perpendicular flange at the end of the lugs, the inboard face of the plate 66.2 thereby securely holding the wear plate 77 in position on the plate 66.2, and preventing any relative rotation or movement when the pivot 73.1 and lock member 62 slide over it during rotation.

[0124] The wear plate 77 assists to also reduce friction between the pivot leg 73.1 and the plate 66.1. If desired, further friction reduction means, such as rollers at the base of the pivot leg 73.1 can be provided, but this will add additional cost and parts to the current system.

[0125] In order to provide as much rigidity to the handle 76 as possible, due to the required length of the handle, a reinforcing piece 76.5 is provided. Whilst the housing 76.2 can be made larger and thus not requiring such a reinforcing piece, to make the housing 76.2 too large, thereby removing the need for a reinforcing piece 76.5, risks adding a large amount of weight and thus a greater amount of inertia for its operation.

[0126] It will be noted in figures 8 and 9 that the cam pin 50 has its planar surface 51 extending wholly between the inside surfaces of the plates 66.1 and 66.2. By contrast, in order to maintain the strength of the pin to an optimum extent, by minimising the extent of surface 51, in the embodiment of figures 18 to 20 the planar surface 51 extends a lesser distance because the pin 50 has, protruding into the space between the plates 66.1 and 66.2, a cylindrical boss 50.1 which passes through he plate 66.2 and a similar boss ( not illustrated) which passes through the plate 66.1. [0127] The device described above thus provides a device wherein a front end loader is automatically locked to the vehicle frame by means of a spring loaded lock member. The continual bias provided by the torsion spring 72 ensures that even if the handle or latch were accidentally contacted or bumped during use, the cam pin 50 is biased to the locked condition.

[0128] Where ever it is used, the word "comprising" is to be understood in its "open" sense, that is, in the sense of "including", and thus not limited to its "closed" sense, that is the sense of "consisting only of. A corresponding meaning is to be attributed to the corresponding words "comprise", "comprised" and "comprises" where they appear.

[0129] It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text. All of these different combinations constitute various alternative aspects of the invention.

[0130] While particular embodiments of this invention have been described, it will be evident to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments and examples are therefore to be considered in all respects as illustrative and not restrictive, and all modifications which would be obvious to those skilled in the art are therefore intended to be embraced therein.

Claims

1. An automatic locking device for attaching a first member to a second member, said device including:

• a receiving structure provided on said second member, said receiving structure including a first angled surface;

• a mounting structure provided on said first member and adapted to engage said receiving structure for releasably attaching the first member to the second member; said mounting structure including a second angled surface; said second angled surface being adapted to cooperate with said first angled surface;

• pivoting engagement means for pivotably engaging the mounting structure and the receiving structure, said engagement means having a pivot axis for providing pivoting movement of the mounting structure and the receiving structure between an engaged position and a disengaged position;

• cam means for releasably locking the mounting structure and the receiving structure in said engaged position, said cam means being movable between a locked condition and an unlocked condition;

• latching means for releasably locking said cam means in said locked condition, said latching means being operably connected to said cam means, said latching means being movable between a latching position and a release position, said latching means being biased toward the latching position; whereby engagement of said first member and said second member will cause the latching means to move said cam means to said locked condition.

2. An automatic locking device as claimed in claim 1 wherein said latching means includes a lock member.

3. An automatic locking device as claimed in claim 2 further including engagement means provided on said mounting structure; said engagement means being adapted to releasably engage said lock member.

4. An automatic locking device as claimed in claim 3 wherein during pivoting movement of said mounting structure and the receiving structure to their engaged position, the first angled surface contacts the second angled surface causing movement of the biased latching means to its latching position wherein the cam means releasably couples the mounting structure to the receiving structure, and wherein the lock member engages the engagement means provided on the mounting structure thereby releasably locking the cam means in its locked condition; and whereafter movement of the latch means to its release position unlocks the cam means and allows pivoting movement between the mounting structure and the receiving structure from their engaged position to their disengaged position.

5. An automatic locking device as claimed in any one of claims 1 to 4 wherein said cam means includes means for positive engagement between the mounting structure and the receiving structure.

6. An automatic locking device as claimed in any one of claims 1 to 5 wherein said cam means includes an off-centre cam.

7. An automatic locking device as claimed in any one of claims 1 to 6 wherein receiving structure includes at least one recess, said recess being adapted to engage a complementary member of said mounting structure.

8. An automatic locking device as claimed in claim 7 wherein said recess includes an U- shaped opening.

9. An automatic locking device as claimed in claims 7 or 8 wherein said recess is provided with a bearing, said bearing being configured to receive said complementary member provided on the mounting structure.

10. An automatic locking device as claimed in any one of claims 7 to 9 wherein said complementary member includes pin means.

11. An automatic locking device as claimed in any one of claims 7 to 10 wherein said complementary member includes cam means.

12. An automatic locking device as claimed in any one of claims 7 to 9, 11 wherein said complementary member includes cam means, said cam means having a planar surface provided on an outer peripheral surface of the cam means.

13. An automatic locking device as claimed in any one of claims 1 to 12 wherein said receiving structure includes a concave portion upon a corresponding transverse pin of the mounting structure will be resting when the receiving structure and the mounting structure are in an engaged position.

14. An automatic locking device as claimed in any one of claims 1 to 13 wherein said receiving structure further includes a centering guide for aiding an operator in positioning the receiving structure in a predetermined position laterally with respect to the mounting structure.

15. An automatic locking device as claimed in any one of claims 1 to 14 wherein said receiving structure includes a plate and a tab member protruding from a side of the plate in a direction generally perpendicular to the plate, said tab member providing said first angled surface.

16. An automatic locking device as claimed in claim 15 wherein said tab member is adapted to engage a corresponding tab receiving recess provided on the mounting structure.

17. An automatic locking device as claimed in any one of claims 1 to 16 wherein said mounting structure includes a first and a second mounting plate, said plates being disposed in a spaced parallel relationship.

18. An automatic locking device as claimed in claim 17 further including a connecting element in the form of a transverse mounting pin, said pin extending between said plates.

19. An automatic locking device as claimed in any one of claims 1 to 18 wherein said pivoting engagement means includes a transversely mounted pin provided on said mounting structure.

20. An automatic locking device as claimed in claim 18 or 19 wherein each side plate is provided with an aperture extending transversely therethrough for rotatably receiving a cam shaft.

21. An automatic locking device as claimed in any one of claims 1 to 20, said locking device including torsion spring means for normally biasing said latching means toward the latching position.

22. An automatic locking device as claimed in claim 21 wherein said torsion spring means are tensioned between a mounting plate and said cam means.

23. An automatic locking device as claimed in claim 21 or 22 wherein said latching means are mounted on said cam shaft for movement toward and away from said mounting plate.

24. An automatic locking device as claimed in any one of claims 21 to 23, said locking device including compression spring means for normally biasing said latching means toward said mounting plate.

25. An automatic locking device as claimed in claim 245 wherein said compression spring means is disposed between the latching means and a handle provided on said mounting means.

26. An automatic locking device as claimed in any one of claims 1 to 25, said locking device including compression spring means for normally biasing said latching means toward the latching position.

27. An automatic locking device as claimed in any one of claims 18 to 26, said locking device including compression spring means for normally biasing said lock member toward a locked position in registry with either an aperture or a recess provided on said mounting plate.

28. An automatic locking device as claimed in any one of claims 18 to 27 wherein said engagement means includes an aperture formed in said mounting plate and wherein said latching means includes said lock member, said aperture being adapted to releasably engage said lock member.

29. An automatic locking device as claimed in any one of claims 18 to 28 wherein said engagement means includes a recess formed in said mounting plate and wherein said latching means includes said lock member, said recess being adapted to releasably engage said lock member.

30. An automatic locking device as claimed in any one of claims 2 to 29 wherein said lock member includes said second angular surface.

31. An automatic locking device as claimed in any one of claims 1 to 30 further including a release handle, said handle being operative to move said latching means to said release position.

32. An automatic locking device as claimed in claim 31 wherein said release handle is attached to the cam shaft to assist in rotating said latching means against said torsion spring means.

33. An automatic locking device as claimed in claim 32 wherein said latching means includes a projection extending in a direction generally perpendicular to the release handle and wherein said handle includes a complementary aperture, said complementary aperture being adapted to receive said projection, the arrangement being such that when the mounting structure and the receiving structure are in a locked condition, a compression spring disposed between the latching means and the release handle biases the release handle outwardly thereby disengaging the projection and the complementary aperture; and whereafter the lock member is moved to an unlatched position by an operator, the projection can be positioned in registry with the complementary aperture to thereby enable the operation of the release handle.

34. An automatic locking device as claimed in any one of claims 1 to 33, wherein said handle and said latching means are integrally formed.

35. An automatic locking device as claimed in claim 34, wherein said handle provides a portion for grasping by a user on either side of its centre of rotation.

36. An automatic locking device as claimed in claim 34 or 35, wherein said handle and said latching means are mounted on said cam shaft so as to be able to pivot laterally with respect to the rotation axis of said cam shaft.

37. An automatic locking device as claimed in claim 36 wherein a recess is provided in said handle to allow said handle to pivot with respect to said cam shaft.

38. An automatic locking device as claimed in any one of claims 1 to 37 further including a flag member for indicating that the cam means is in said unlocked or locked condition.

39. An automatic locking device as claimed in any one of the preceding claims wherein a wear member is provided on a surface of second member for a portion of said latch member to make sliding contact.

40. An automatic locking device as claimed in claim 42 wherein said wear member includes an indication of the locking or unlocking direction of rotation of said latching means.

41. A method for releasably attaching a first member to a second member, said method including the steps of:

• providing a receiving structure on said second member,

• providing a mounting structure on said first member,

• providing pivoting engagement means for pivotably engaging the mounting structure and the receiving structure, said engagement means having a pivot axis for providing pivoting movement of the mounting structure and the receiving structure between an engaged position and a disengaged position;

• providing cam means for releasably locking the mounting structure and the receiving structure in said engaged position; and

• and triggering said locking action by actuator means on said receiving structure and or said mounting structure.

42. A method as claimed in claim 41 wherein said cam means includes means for positive engagement between the mounting structure and the receiving structure.

43. A method as claimed in claim 41 or 42 wherein said cam means includes an off-centre cam.

44. An automatic locking device or method as claimed in any one of the preceding claims wherein said first member is a vehicular attachment means, and said second member is a vehicle.

45. An automatic locking device or method as claimed in any one of claims 1 to 43 wherein said first member is an implement, and said second member is a vehicular attachment means.

46. A device or method as claimed in claim 44 or 45 wherein said vehicular attachment means is a front end loader, a rear end loader, a side loader or any appropriate means which needs attachment to a vehicle or to which an implement has to be attached.