US2500047A - Adjustable clamp truck - Google Patents

Description

March 7, 1950 H. L. SMITH ADJUSTABLE CLAMP .TRUCK 2 Sheets-Sheet l Filed 001;. l, 1947 March 7, l950 H. L. SMITH ADJUSTABLE CLAMP TRUCK 2 Sheets-Sheet 2 Filed Oct. l, 1947 INVNTOR.

' A fr0/@N5 Y Patented Mar. 7, 1950 ADJUSTABLE CLAMP TRUCK Henry .L Smith,"learwater,: Fla., assigner to Food Machinery and Chemical Corporatioma corporation of Delaware Application October 1, 1947,'1Serial No. 777,314

4 Claims. (Cl. 214-655) This invention relates to the 1 art of .clamp trucks and particularly to such trucks which are adjustable to loads varying in width.

It is .an object of Vthis linvention to provide .a novelv adjustable clamp truck, having an overriding toggle locking the truck. in clamping position, with a novel means for adjusting the truck 'to handling boxes varying in length so thatrwhen thus locked it will t a boX of a particular length ing outwardly from them'embers mand having guidelugs I1 thereon.

. Thefmembers I3, I., I5 and I8 are recessed rinto .the ,front faces of vthe side members I2l and are held in placebo/.metal straps i8 whichare bolted to the front :faces of 'the 4side members.

.Bearing plates (I9 are also recessed into Athe lower ends of the side members TIZandsecured :thereto by 'the same bolts whichattach the straps in accordance with the adjustment of the truck. 10 .'18, to thesemembers.

Another objectof the invention is to p-rovide :Provided on the members I2 are blocksr 25 in a toggle locking clamp truck with a mechanism lWhichfis Xed a shaft 23, carriage Wheels 2I1befor adjusting the space between the jaws, when `ing cmounted on this shaft -just inside the these are in clamping relation, which is relatively blocks' 25. simple to operate and which is universal in the l5 Shaft .25 also carries a pedal bracket-,23 on degree of adjustment, that is: which can beset which ispivotally mounted a clamping'pedal 29. anywhere between the maximum and minimum .'-Provided onthe crossemembers I3 and I4 are limits of the adjustment. bearings 35. and `Idliriwl'iioh is journalled'a'shaft The manner of accomplishing Athe foregoing 31 having a smooth portion 38 and a threaded objects as well as further objects and advantages .portion 39. Collars All prevent vertical shifting will be made manifest in the iollowing'descripof .the shaltl'gin the bearings and36. VAThe .tion taken in connection with the accompanying shaft'3'l ,is adapted tobe rotated by a handle 4l ydrawings in which: mounted on its upper end.

Fig. 1 is a front elevational view of a preferred Laterally shiftable through the openings embodiment of the hand truck of this invenformed betweenthe members `I5 and I6. bearing tion with the truck adjusted for a minimum "plates I9, and straps I8, are box clamping jaws separation vof the jaws and showing the latter'in 42, these having arms 43 bent forwardly thereclamping position. from, with boxvgrippingteeth 44 extending. in-

.Fig. 2 is a side elevational View of Fig. 1. lwardly, froml outer loweriedges of these s arms.

Fig. 3 .isan enlarged vertical sectional view 3o These jaws 42 .lie ,ushvwith the, cross-members taken on the line 3 3 of' Fig. 1 and illustrating I5 and 16. the adjusting screw and guide shaft of the clamp- Disposed parallel zwith the shaft 3l, and 1. on ing mechanism. foppositesidesthereof, are pairs ofguide bars -45 Fig. 4 is a fragmentary front elevational View :which arezsecured to the front and-rear faces similar to the lowerportion of Fig. 1 and show- 35 of the cross'members Id and I5 so'thatthe bars ing the same adjustment of vthe truck with the of eachpairareparallel. clamping mechanismactuated to extend. the jaws PiVOIed al1-.their .IOWGI eHdS'OIl the ljws 42..:are preliminary to a clamping operation. .levers 46each. of fthese comprising a bar-Which Fig. 5 is a view similar tothelower portion of :lies flushl against thepcross-member rI5 vand one Fig. 1 with the mechanism adjusted to the maxi- 40 Vof the-.jaws 42. mum spacing of the jaws in clamping position. Slideable on the, smooth shaft portion g 33 gis Fig. 6 is a view similar to Fig. 5 showing the .a slideblock 5I) while the threaded'portion'fSBzis jaws expanded in readiness to receive a load be- Screwed :into a. screw block 5I. The block. lillrhas tween the jaws. verticalkerfsiin which iare pivoted links; Ithe Fig. 7 is an enlarged horizontal cross-sectional 45 outer ends'o'f which `are pivotally connected 4to View taken on'the line I-I of Fig. 5. the upperl ends offthe levers 46. The blocklhas Fig. 8 isa similar-view taken on the line 8-18 vertical kerfs in which are pivoted linksipthe of Fig. 5. outer ends of which are pivoted at fulcrumipoints Referring speCiCally to the drawings, the l5t to the levers lI-E. The slide block 5l) has a jaw clamp truck It, shown therein as embodying the A50 `opening'peclal E0 which is connected by alink` 6I invention, includes a carriage frame Il having to the upper end of the Clamping pedal 2g handle side members l2 which are rigidly connected and held in spaced relation by an upper Operation cross-member I3, a middle cross-member I4 and In Fig. 1, the slide block 50 is in its uppermost lower cross-members I5 and I6, the latter extend- 55 position to which it was elevated by the operafor depressing the foot pedal 29. This separates the upper ends of the levers 46 and shifts the jaws 42 inwardly into their innermost box clamping position.

The block 5l4 is adjusted as shown in Fig. 1 when it is desired to handle a stack of boxes, the length of which equal the distance here shown between the inner faces of the arms 43 of the jaws 42.` No boxes are shown in Fig. 1 as they would hide the mechanism. If the truck I were so adjusted and then operated on such a stack, the teeth 44 would be driven along the top surface of the floor beneath the ends of the lowermost box of the stack. The operator would then continue to press his foot on the pedal 29, while pulling backward vigorously on the upper ends of the handle members I2 so as to lift the stack and balance this on the wheels 2l while trucking it to a desired destination.

The stack is set down by reversing the steps of the process by which it was picked up. The operator then tromps on the pedal B which depresses the slide block and swings the upper ends of the levers 46 inwardly into the position in which these are shown in Fig. 4.

This expands the jaws 42, releasing the stack and permitting the truck to be withdrawn from about the stack.

When the jaws have been shifted inwardly (as shown in Fig. to grip and support a stack of boxes so that this may be carried from place to place on the truck l0, it is to be noted that the slide block 50 has been lifted so as to overthrow the toggle (comprised by the links 53) past the line connecting the pivots at which these links are joined to the upper ends of the levers 56. This prevents accidental expansion of the jaws 42 while a load is being carried on the truck i0.

The adjustment of the truck I0 for handling boxes of any particular length, between the minimum and maximum lengths indicated in Figs. l and 5, is accomplished by rotating the shaft 31 by the handle 4l. The action of the threads on the threaded portion 39 of the shaft 31 moves the block 50 up or down which varies the spacing between the fulcrum points 56 of the levers 46. As this distance increases the distance between the jaw arms 43 increases both for their expanded and clamping positions.

A particular advantage of the truck I0 is that merely by rotation of the handle 4l, the truck may be adjusted to fit any particular length of box in between the maximum and the minimum sizes the truck is adapted for handling.

It is also helpful that this adjustment may be made while the truck is resting close to a stack just before the operator undertakes to pick the stack up with the truck. As he rotates the handle 4| he may look downwardly at the stack and compare its width with the space between the arms 43 while the pedal 29 is depressed. When this spacing of the arms 43 is exactly equal to the length of the boxes of the stack, the operator then merely depresses the pedal 60 and proceeds to pick up the stack in the manner above described.

I claim:

1. In a clamp truck the combination of: a wheeled carriage frame; a pair of box clamping jaws mounted on said frame for movement inwardly from expanded position to clamping position and return; a pair of upright levers the lower ends 0f which connect with said jaws; a vertical shaft lying substantially in the plane of said levers and between these; means for rotatably mounting said shaft on said frame; threads on a portion of said shaft, said shaft also having a smooth portion; a slide block slideable on said smooth portion of said shaft; links pivotally connected to said slide block and to upper ends of said levers; a screw block into which the threads of said shaft are screwed; links pivotally connecting at their inner ends with said screw block at their outer ends with said levers at fulcrum points on the latter; means for shifting said slide block on said shaft to rock said levers about said fulcrum points to expand or retract said jaws on said truck; and means to rotate said shaft to alter the spacing of said fulcrum points.

2. A combination as in claim 1 in which vertical guide bars are provided in pairs for guiding said links and blocks in their various movements.

3. A combination as in claim 2 in which said slide block and screw block have kerfs into which said links extend and in which said links are pivoted to said blocks; said pairs of guide bars being spaced apart substantially the width of said slide blocks, the bars in each pair being spaced substantially the thickness of said links.

4. In a clamp truck the combination of z a frame comprising a pair of handle side members; a pair of wheels rotatably journalled on said side members; at least three cross-members rigidly uniting said frame side members; a pair of box clamping jaws slideably mounted on the lower of said cross-members; bearing means provided on two of said cross-members; a shaft journalled in said bearing means, said shaft having a threaded portion and a smooth portion; a screw block into which said threaded portion screws; a slide block slideably receiving said smooth portion of said shaft; two levers, the lower ends of which are pivotally connected respectively to said jaws; links connecting said screw block to said levers at fulcrum points thereon; links connecting said slide block to other points on said levers; means for vertically moving said slide block on said shaft to shift said jaws inwardly and outwardly between expanded and box clamping positions; guides for guiding said clamping jaws along rectilinear paths; and means for rotating said shaft to move said screw block to various adjusted positions on the shaft to alter the distance said fulcrum points are separated.

HENRY L. SMITH.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2 024,267 Bartlett Dec. 17, 1935 2,109,305 Stine Feb. 22, 1938 2,316,614 Pierce Apr. 13, 1943 2-,328 224 Moorehead Aug. 31, 1943 2,367,752 Broome Jan. 23, 1945

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