Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
  • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
  • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
  • B66F9/075—Constructional features or details
  • B66F9/12—Platforms; Forks; Other load supporting or gripping members
  • B66F9/14—Platforms; Forks; Other load supporting or gripping members laterally movable, e.g. swingable, for slewing or transverse movements
  • B66F9/142—Movements of forks either individually or relative to each other
  • B66F9/143—Movements of forks relative to each other - symmetric
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
  • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
  • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
  • B66F9/075—Constructional features or details
  • B66F9/12—Platforms; Forks; Other load supporting or gripping members
  • B66F9/14—Platforms; Forks; Other load supporting or gripping members laterally movable, e.g. swingable, for slewing or transverse movements
  • B66F9/147—Whole unit including fork support moves relative to mast
  • B66F9/148—Whole unit including fork support moves sideways

Definitions

• This invention relates generally to a carriage assembly having a laterally shiftable fork structure and more particularly to such an assembly mounted to a mast structure of a lift truck.
• carriage assemblies which have a side shifter, that is, a frame which shifts laterally relative to the mast assembly and carries the forks with it, it is particularly important to have clear forward and downward vision for the lift truck operator, since this allows the operator to visually follow lateral movement and downward tilting of the forks and associated load.
• a side shifter that is, a frame which shifts laterally relative to the mast assembly and carries the forks with it
• a load lifting apparatus has a mast assembly and a carriage assembly.
• the carriage assembly has an upper member and a lower member and is mounted to and translatable along the mast assembly.
• a side shifter having upper and lower bars, is mounted to and laterally translatable along the upper and lower members.
• a generally "L" shaped tine has a generally vertical leg and a generally horizontal leg. Means are provided for mounting a top end portion of the vertical leg to transfer substantially only horizontal forces to the upper bar. Means are also provided for mounting the bottom end portion of the leg to transfer vertical forces to the lower bar. Further, means are provided for maintaining the lower bar from moving laterally away from the lower member, said means being free from interference with relative longitudinal movement between the lower bar and lower member.
• a structure as set out above has the advantage that all vertical forces are taken up by the lower portion of the carriage assembly. As a result, the upper portion of the carriage assembly can be relatively small. This allows relatively free forward and downward view for an operator of a lift truck which has such a carriage assembly.
• the ability of the assembly to lift a load is improved since the effective lever arm, from the load on the tines to the lower portion of the carriage assembly, is shorter than the effective lever arm in prior art structures (from the load to the upper portion of the carriage assembly).
• side shifting is provided. Also, a close fit can be maintained between the lower member and the lower bar and apparatus can be provided which keeps the tine from rotating away from the side shifter and which can be easily removed to replace or repair damaged tines, or to mount tines of specialized shapes and/or sizes.
• Figure 1 illustrates, in perspective view, one embodiment of the present invention as mounted to a conventional lift truck
• Figure 2 illustrates, in side sectional partial view, the embodiment of Fig. 1 in further detail
• Figure 3A illustrates, in partial perspective view, taken looking downwardly and rightwardly from in front and to the left of the truck, a detail in the structure of the embodiment of Figure 1;
• Figure 3B illustrates, in partial perspective exploded view, a portion of the structure shown in Figure 3A;
• Figure 4 illustrates a view taken along the line IV-IV of Figure 2.
• Figure 5 illustrates a view taken along the line V-V of Figure 2.
• FIG 1 illustrates a load lifting apparatus or lift truck 10 having a generally vertically oriented mast structure 12 having a frontward facing or fore portion 14.
• a carriage assembly 16 is mounted to the mast structure 12 for movement vertically up and down along the fore portion 14 thereof.
• the carriage assembly 16 includes a roller bracket 17, seen best in Figures 4 and 5, which rolls within movable uprights 18 on rollers 19a and 19b.
• An upper generally horizontal member 20 and a lower generally horizontal member 22 are each connected to the roller bracket 17.
• a chain assembly 23 pulls the carriage assembly 16 upwardly along the movable uprights 18 as they are raised by cylinders 25.
• the tines 34, 36 are preferably shifted laterally on the side shifter 24 by cylinders 37a and 37b, respectively.
• the tines 34 and 36 are substantially identical. Generally, the tines 34 and 36 each have a generally vertical leg 38 having a top portion 40 and a bottom portion 42. The tines 34 and 36 also have a generally horizontal leg 44. The generally vertical leg 38 and the generally horizontal leg 44 are joined together at an apex 46. The generally vertical leg 38 is positioned generally parallel to the mast structure 12 with the apex 46 aligned downwardly and joining the bottom portion 42 and the horizontal leg 44. The generally horizontal leg 44 is positioned to extend generally perpendicularly away from the fore portion 14.
• means 52 are provided for mounting the top end portion 40 of the vertical leg 38 to transfer substantially only horizontal forces to the upper bar 26 of the side shifter 24.
• the means 52 includes a plate 54 attached to extend downwardly from the upper, generally horizontal member 20, preferably to the height of the upper bar 26. Since only horizontal forces are taken up by the upper member 20, it need not be bulky or extend far vertically. Thus, forward vision past the upper member 20 is relatively unobstructed.
• An extension 56 of the vertical leg 38 of the tine 36 extends upwardly therefrom adjacent the mast structure 12.
• Appropriate bearing plates 60 and 62 are positioned respectively between the plate 54 and the member 58 and between the member 58 and the extension 56.
• the bearing plates 60, 62 are a plastic material such as UHMW polyethylene.
• Means 64 is additionally provided for mounting the bottom end portion 42 of the vertical leg 38 to transfer vertical forces which are exerted downwardly upon the horizontal tine 44 to the lower bar 28 of the side shifter 24. Such forces are then transferred, in a manner which will shortly be apparent, to the lower member 22, and from there, via the roller bracket 18, to the mast structure 12.
• a pair of arms 66 are carried by the tines 34 and 36 and extend toward the mast structure 12.
• the arms 66 are positioned and of a construction sufficient to extend to a position above a top 67 of the lower bar 28.
• An appropriate bearing plate 68 preferably of a plastic material, is attached to a bottom 69 of each of the arms 66 and provides sliding contact between the lower bar 28 and the bracket 66.
• Means 71 is provided for maintaining the lower bar 28 from moving laterally away from the lower member 22, while allowing relative longitudinal movement between lower bar 28 and lower member 22.
• a generally horizontal channel 70 is provided which extends longitudinally along the lower bar 28.
• the channel 70 is formed by an "L" shaped bar 72 and the lower bar 28, the “L” shaped bar 72 being attached to the lower bar 28.
• the channel 70 opens upwardly.
• a pair of brackets 74 are connected to the roller bracket 18 and have a finger 76 which extends downwardly into the channel 70.
• Means 78 is provided for laterally adjusting the position of the fingers 76 within the channel 70.
• the means 78 includes a plurality of bolts 80 which fit within laterally extending slots 82 in the brackets 18. To adjust the lateral positions of the fingers 76, one simply backs off the bolts 80 and slides the brackets 74 leftwardly or rightwardly as desired up to the limits of movement provided by the slots 82. Thereafter, the bolts 80 are simply tightened in place. This assures snug positioning of the side shifter 24 adjacent the lower member 22. Play is thus reduced while side shifting can take place. The side shifter 24 is also prevented from coming off.
• Retaining means 84 is provided for retaining the bottom portion 42 of the generally vertical leg 38 of the tine 36 adjacent the lower bar 28.
• the particular retaining means 84 illustrated includes a structure 86 attached, by a retainer, such as a bolt 88, to the tine 36 adjacent its apex 46, and more particularly attached to the bottom portion 42 of the vertical leg 38 of the tine 36.
• a retainer such as a bolt 88
• a ridge 89 which extends downwardly from a bottom 90 of the lower bar 28, the ridge 89 having one side 91 which faces away from the tine 36.
• the structure 86 is connected to the tine 36 in such a manner that it extends upwardly past the ridge 88 to adjacent the one side 91 of the ridge 89 and the bottom 90 of the lower bar 28.
• the structure 86 can be removed by removing the bolt 88 whereby the tine 36 can be readily removed.
• a first bearing structure 92 is attached to and extends along either the lower bar 28 or the lower member 22 and is in sliding contact with the other thereof.
• the first bearing structure 92 is positioned to transfer forces downwardly from the lower bar 28 to the lower member 22.
• vertical forces which are transferred from the tines 34 and 36 to the lower bar 28 are further transferred via the "L" shaped member 72 to the lower member 22, which is located below the "L" shaped member 72.
• the first bearing structure 92 is a longitudinally extending bar, preferably of an organic polymeric material such as ultra high molecular weight polyethylene, with the bar having an "L" shaped cross-section with a horizontal leg 93 of the "L” being held between a top surface 94 of the lower member 22 and the bar 72 (which is attached to the lower bar 28 and which, as has previously been mentioned, serves to define, the horizontal channel 70).
• the first bearing structure 92 is attached to the lower member 22 and is in sliding contact with the lower bar 28.
• the lower member 22 is shorter than the lower bar 28.
• a second bearing structure 96 is attached to and extends along a respective one of the lower bar 28 and the lower member 22 and is in sliding contact with a respective other thereof.
• the second bearing structure 96 is positioned to transfer forces upwardly from the lower bar 28 to the lower member 22.
• the second bearing structure 96 is attached to the lower member 22. That member is somewhat shorter than is the lower bar 28.
• the second bearing structure 96 is of the same shape as the first bearing structure 92 and of the same material thereof.
• the bearing plates 60, 62 and 68 are also generally of this same material.
• a member 98 which may be attached to or may be integral with the lower bar 28, extends therefrom to below the lower member 22.
• the second bearing structure 96 is attached with a generally horizontal leg 99 thereof in sliding contact between the member 98 and a bottom 100 of the lower member 22.
• a generally vertical leg 101 of the first bearing structure 92 and a generally vertical leg 103 of the second bearing structure 96 are vertically oriented between the lower member 22 and the lower bar 88 and are preferably in sliding contact with the lower member 28 and attached to the lower member 22.
• shim means 102 Adverting particularly to Figures 3A and 3B, there is illustrated therein shim means 102 which serves for providing tight sliding contact between the second bearing structure 96 and the bottom 100 of the bar 98.
• an "L" shaped member 104 is positioned with a longer leg 106 thereof between the lower member 22 and the horizontal leg 99 of the second bearing structure 96.
• the "L" shaped member 104 having a longer leg 106 of a proper thickness to assure good contacting relation between the bar 98 and the horizontal leg of the second bearing structure 96 can be selected at assembly.
• the shim means 102 could be positioned between the first bearing structure 92 and the top surface 94 of the lower member 22.
• the horizontal leg 93 of the first bearing structure 92 serves to transfer forces downwardly from the lower bar 28 to the lower, member 22 and the horizontal leg 99 of the second bearing structure 96 serves to transfer forces upwardly from the lower bar 28 to the lower member 22.
• the vertical legs 101, 103 of the first bearing structure 92 and the second bearing structure 96 serve as means 108 for providing sliding contact between the lower bar 28 and the lower member 22 for transferring forces generally horizontally inwardly from the lower bar 28 to the lower member 22.
• An apparatus as described above is particularly useful with a lift truck wherein loads may be shifted sidewardly relative to a mast assembly and wherein the forks may be shifted sidewardly independently.
• the overall weight of the device can be reduced, since the bottom portion of the carriage is nearer the position on the forks, where loads are borne than is the upper portion of the carriage. As a result, it is not required to be as strong (and heavy) as are the upper portions of prior art carriages. Adjustments are provided so that a close fitting construction is maintained, even if manufacturing tolerances are relatively large.

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• Engineering & Computer Science (AREA)
• Transportation (AREA)
• Structural Engineering (AREA)
• Civil Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Geology (AREA)
• Mechanical Engineering (AREA)
• Forklifts And Lifting Vehicles (AREA)

Priority Applications (6)

Applications Claiming Priority (2)

Publications (1)

Family

ID=22154560

Family Applications (1)

Country Status (5)

Cited By (5)

Families Citing this family (2)

Citations (2)

Family Cites Families (5)

• 1980
  • 1980-09-22 WO PCT/US1980/001265 patent/WO1982000997A1/en active IP Right Grant
  • 1980-09-22 DE DE8181901011T patent/DE3071512D1/de not_active Expired
  • 1980-09-22 EP EP81901011A patent/EP0060245B1/en not_active Expired
• 1981
  • 1981-06-18 NO NO812077A patent/NO150756C/no unknown
  • 1981-09-09 JP JP1981133174U patent/JPS5771197U/ja active Pending

Patent Citations (2)

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