This invention relates to devices for use with equipment having a loader bucket, and, more particularly, to a clamp-on fork lift attachment which may be secured to the blade portion of the loader bucket allowing the equipment to function as a fork lift.
Fork lifts are commonplace in industry and widely used for moving objects resting on pallets and for other purposes. Equipment of this type generally includes a motorized truck having a vertically oriented carriage along which two spaced forks or tines are moveable in and up and down direction. The tines may also be moved toward and away from the truck to assist with the manipulation of loads placed on the tines.
While dedicated fork lifts of the type described above are effective and useful in a variety of applications, they are not always available on job sites and many do not have the size or lifting capacity to handle larger loads. One solution to this problem has been suggested, for example, in U.S. Pat. Nos. 6,022,184; 4,274,798 and 3,325,023. These patents disclose fork lift attachments which may be temporarily clamped onto the blade portion of the loader bucket found on equipment such as backhoe loaders and front end loaders. Generally, fork lift attachments comprise two tines which are spaced from one another and clamped onto the substantially planar blade portion of the loader bucket immediately rearward from its cutting edge. Each tine has a lower bearing surface that extends beneath the blade portion of the loader bucket and a screw-type clamp that contacts the top surface of the blade such that the blade is sandwiched between the clamp and lower bearing surface. The backhoe loader, front end loader or other piece of equipment with a loader bucket is thus temporarily converted to a fork lift and may be employed to lift and manipulate objects in the manner of a dedicated fork lift.
This invention is directed to a clamp-on fork lift attachment which may be temporarily secured to the blade portion of a loader bucket used on equipment such as backhoe loaders and front end loaders.
In one presently preferred embodiment, the attachment of this invention may include a pair of spaced tines each having a lifting plate mounted at the forward end, a leveling indicator mounted at the rearward end and a clamping device with a tie-down element. The lifting plate and tie-down element provide structure where chains, cable, rope or the like may be attached to secure or stabilize objects placed on the tines, and/or to assist in lifting items with the tines. The leveling indicator is mounted in a position on each tine so that it extends beneath the blade portion of the loader bucket and assists in maintaining the tines in a parallel, level orientation relative to the loader bucket.
The attachment of this invention may also include a stabilizer bar which connects between the two tines clamped onto the loader bucket. The stabilizer bar may include telescoping structure allowing it to adjust to different spacings between the tines, as required. Further, the stabilizer bar functions to add rigidity to the tines and resist flexing of one tine relative to the other under the application of load.
The structure, operation and advantages of the presently preferred embodiment of this invention will become further apparent upon consideration of the following description, taken in conjunction with the accompanying drawings, wherein:
Referring now to the drawings, the clamp-on fork lift attachment 10 of this invention comprises a first tine 12 having a first clamping mechanism 14, a second tine 16 having a second clamping mechanism 18 and a stabilizer bar 20 which may be connected between the first and second clamping mechanisms 14, 18 of tines 12, 16. The attachment 10 may be mounted to the blade portion 22 of a loader bucket 24, illustrated schematically in
As best seen in
In one presently preferred embodiment, the tine 12 is formed from generally rectangular-shaped tube stock having a forward end 26, a rearward end 28, an upper surface 30, a lower surface 32 and a hollow interior 34. A lifting plate 36 is mounted at the forward end 26 of tine 12. The lifting plate 36 has a base 38, a leg section 40 and an end section 42 extending between the base 38 and leg section 40. Although the lifting plate 36 may be fabricated in separate pieces which are welded together, it is preferred that a single plate be bent such that the end section 42 is substantially perpendicular to the base 38 and the leg section 40 extends at an angle from the top of the end section 42 into contact with or at least immediately adjacent to the upper surface of the base 38. A cavity 44 is formed between the base 38 and leg section 40, and an aperture 46 may be formed in the base 38 which is spaced from the cavity 44. The cavity 44 and aperture 46 may receive a chain, cable, rope or other means of attachment for lifting an object which is not resting on the tines 12, 16, or for tying down a load on the tines 12, 16 so that it does not shift or fall off. Preferably, the lifting plate 36 is secured to the forward end 26 of tine 12 by welding the end section 42 thereto.
A leveling indicator 48 is preferably mounted to the rearward end 28 of tine 12, as best seen in
The clamping mechanism 14 includes a vertical support 54 mounted at its bottom end to the upper surface 30 of tine 12 near rearward end 28. A first arm 56 is welded along one side edge of the vertical support 54, and a second arm 58 attaches to its opposite side edge so that the arms 56, 58 are laterally spaced from one another and extend in a direction toward the rearward end 28 of tine 12. At least a portion of each arm 56, 58 rests atop the upper surface 30 of tine 12 and may be welded thereto. An upper guide bracket 60 and a lower guide bracket 62 are connected between the arms 56, 58. The upper guide bracket 60 is formed with an opening 64 that vertically aligns with an internally threaded nut 66 secured to the lower guide bracket 62. A threaded rod 68 may be inserted through the opening 64 in the upper guide bracket 60 and into threaded engagement with the nut 66 in the lower guide bracket 62, as shown in
In one presently preferred embodiment, a tie-down element 76 is mounted to the upper end of the vertical support 54 of clamping mechanism 14. The tie-down element 76 includes a ring 78 and an extension 80 which is spaced from the ring 78 forming a slot 82 between them. The ring 78, extension 80 and slot 82 provide points of attachment for a chain, cable, rope of the like which may be used to secure items placed on the tines 12, 16 or other purposes. Additionally, a rod 84 is connected between and near the bottom portion of the arms 56, 58 of clamping mechanism 14, for purposes to become apparent below.
Referring now to
Referring now to
The second tine 16 may be mounted to the loader bucket 24 in the same manner as tine 12 discussed above. When both tines 12, 16 are in position, the stabilizer bar 20 may be connected between them. The coupler 98 of end tube 88 of stabilizer bar 20 may be mounted to the clamping mechanism 14 of tine 12 by placing the vertical support 54 between the side plates 102, 104 and in engagement with connector plate 106. The ends of side plates 102, 104 clear the vertical support 54, and a pin 114 may be inserted into their aligning bores 103, 105 to secure the coupler 98 in place. The same procedure is employed in mounting the coupler 100 to the clamping mechanism 18 of the other tine 16. As noted above, the end tubes 88 and 90 telescope within center tube 86 so that the overall length of stabilizer bar 20 may be varied, depending on the spacing between tines 12 and 16, e.g. from a retracted position shown in
It is contemplated that the installation of attachment 10 described above may be varied if sufficient manpower is available. The stabilizer bar 20 may be mounted to the clamping devices 14, 18 of respective tines 12, 16 first, in the same manner noted above, and then the entire assembly may be moved into position for mounting to the blade portion 22 of loader bucket 24. This would avoid the potential issue of misalignment between the bores 92, 94 in the center tube 86, and one of the bores 96 in each of the end tubes 88, 90, which could occur if the tines 12, 16, when individually mounted to loader bucket 24, are not spaced from one another at the appropriate distance.
While the invention has been described with reference to a preferred embodiment, it should be understood by those skilled in the art that various changes may be made and equivalents substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. For example, while one preferred embodiment of the present invention is a clamp-on fork lift attachment comprising two tines each mounted to the blade portion of a loader bucket with a space between them, it is contemplated that a single tine could be employed to form the attachment herein under circumstances such as when an object is to be lifted using a cable, chain rope or the like connected to the lifting plate and/or tie-down element of this invention. As such, the clamp-on fork lift attachment is considered to include at least one tine.
Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.