US2457646A - Lifting tongs - Google Patents

Description

LIFTING TONGS FiledvMay 16, 1946 INVENTOR. UZ Tgivwl Zag/@res Patented Dec. 28, 1948 UNITED STATES PATENT OFFICE n LIFTING TONGS Anthony IWilmot Dali'eres, Lafayette, La. Application May 16, 1946, `Sel'll N0. 670,165

z claims. l

The present invention relates to improvements in lifting tongs and more particularly relates to lifting tongs more suitable to the handling of cement blocks of lthat type having Iair passages therethrough It has been my observation that the greatest drawback to the popular use of cement blocks for building purposes is |the difllculty in handling blocks 8 x 8 x 16'l and blocks 12" X 8" x 16" weighing thirty-two to iifty pounds. These cement blocks usually have three hollow squares or air passages therethrough which afford convenient channels to admit the jaws of my improved tongs.

An object of the .invention is to provide improved lifting tongs constructed Iand arrangedA to enable the worker to line up the block as it is being set on the mortar and to do so with ease and convenience.

A further object of the invention is it@ provide an improved lifting tongs in which provision is made for extending the length of the tongs to accommodate blocks of various sizes and heavier and larger objects,

A further object of the invention resides in providing yan improved lifting itongs in which a single lifting movement pressure is exerted on the grips or jaws, it being only necessary to release the gripping handle to d-isengage the tongs Whereupon the ltong-s can be removed from the work by grasping a crossbar 'through which the jaws are not disturbed but may remain in their open position.

A still further object of the invention is to provide an improved lifting tongs useful not only in connection with cement blocks but also for lifting bullions, metal blocks, ingots or the like. i

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims lappended hereto.

In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views, n

Figure 1 is :a ltop plan view of an improved lifting tongs constructed in accordance with the present invention;

Figure 2 is a side elevation of the improved tongs;

Figure 3 is a vertical longitudinal section taken f through the `tongs on the line 3-3 and showing the same in open posi-tion Figure 4 is a horizontal line 4-4 in Figure 2, and f Figure 5 is avertical section of a, detail of in Figure 1 section taken on the gripping jaw .taken on the line 5-5 in Figure l. Referring more particularly to the drawings I0 designates .a fixed `legand I I a movable leg which is in eil'ec-t a lever of the first class inasmuch as the same is pivoted centrally by a bolt or fulcrum pin 'I4' to an adjustable clip within a U-shaped bearing I5 which is adjustably carried by a cross bar I2. f

The'immovable leg I0 is secured to the cross bar I 2 as -by a bolt or other appropriate fastening I3.- This bolt I3 may have a square or other straight line shank, as indicated in Figure 3 to llt a complementally shaped hole in the fixed leg I0 in order to prevent relative rotation of the fixed-leg III upon the cross bar I2; or the free ends of the cross bar I2, as shown in Figure 4 may be bent or toed in or clinched upon the outer side of the fixed leg `Ill to bind the two members I0 and I2 into a non-rotary relationship. This `clinched condition is shown at 36 in Figure 4.

As shown to best advantage in Figure 4, the cross bar I2 ls preferably made from strap metal returned upon itself -to provide the two spaced parallel arms, the free ends of which flank the Afixed leg I0 and receive the bolt I3 while the yoke 33 of the cross bar I2 is perforated .to receive the threaded shank I 6 which projects from and supports the fulcrum bearing I5. Lock nuts I1 and I8 run upon the screw I5 at opposite sides of the'yoke 33 serve to bind the same in adjusted position.

The upper ends of the legs I0 and II .are coupled together by a toggle lever consisting of, la main member I9 which is preferably of tubular form in order to afford a convenient hand grip, this Vmember extending substantially the entire length of the distance between the upper ends of the legs I0 and II land being pivoted at 25 to the upper end of the movable leg II and Iat 24 to the inferior toggle mem-ber 23. This latter member is pivoted at 26 to the upper end of the fixed leg III Aand operates in a slot2'I which is formed only through the top wall of the tubular member I9. It will be observed that the center fulcrum 24 of the-toggle lever is considerably closer` tothe fixed leg I 0 than to the lever leg I I.

As shown more particularly in Figure l the inferior toggle member 23 may be formed of strap metal bent upon itself with ktwo side branches in substantial contact through the majority of vitsvlength where it is received through the slot 21 of the handle memberv I9, but such branchesl diverge at their free ends in order to encompass the upper end of the xed leg I0 to Is in a vertical direction whereby to provide two "f end extensions 20 and 2| adapted to slidably engage opposite sides of the lever` leg II. These extensions 20 and 2| are provided with horizontally registering series of perforations 22 adaptedto be brought into alignment with the pivot bolt 25 for the purpose of selectively shortening or elongating the toggle lever. y

The lower ends of the legs Ill and II carry the grippers or jaws which preferably comprise rub-v ber or other resilient blocks 32 held in retaining frames II which are bolted to cross bars 30 carried by the legs III and II. The bolts are shown at $5 and their heads are preferably countersunk in the material o! the rubber blocks l2 so as not to scratch or mar the surfaces of the blocks or other work to be gripped and lifted.

It will be apparent from the drawings that these rubber blocks 32 are deeper than the frames II In which they are mounted, or in other words substantial masses of the bodies of these blocks Il project inwardly beyond the anges of the frames 3l, which allows of considerable compression of the rubber blocks 32 in the act of gripping the blocks or other work.

In the use of the device, Figure ashows the open position oi the jaws in which the movable lever leg II has been rocked out oi its vertical position by the downward collapse or breaking of the toggle lever I9, 23. In this position the jaws l2 are open and in readiness to be inserted into the passages of a block or upon the sides of any other article. In lowering the device to a block or other object the same will be supported by the cross bar I2. After the jaws 32 have arrived at a proper position for gripping the internal walls o! the cement block or the side walls o! any article, the hand of the operator is transferred from the cross bar I2 to the tubular handle I9, by which act alone the jaws 32 are automatically closed upon the object by a shift of weight. In other words when the weight o! the device is transferred from the cross bar I2 to the handle Il the weight of the device will tend to cause the tongs as a whole to fall while the handle I! remains stationary in the hand of the operator; the net eiIect of which is to tend to straighten the handle from the condition of Figure 3 to that o! Figure 2, accompanied by the approach oi.' the lower end of the lever leg I I to the lower end of the fixed lever leg I0. The Weight of the device descends until the stop 31 encounters the lower edge of the inferior toggle member 23 at which point the jaws are completely closed and the toggle lever is held in a. toggle lock position with the pivots 24, 25 and 26 in substantial horizontal alignment. The togglo lock can therefore not be broken by any force tending to spread apart the jaws 32.y Just before the toggle lock finally closes the inner portions o1 the rubber blocks 32 begin to be compressed and the final upward closing movement of the toggle lever` I9, 23 is to compress these rubber blocks 32 upon the object. The reaction due to the inherent elasticity o! the blocks which tends to force the lower ends oi' the legs III and Il 4 apart encounters the toggle lock across the aligned pivots 24, 25 and 26. This serves to bind the toggle lock tighter in that it cannot jog loose and fall down to the position of Figure 3 casually or accidentally or in other words until it is directly and positively pushed down by the conscious act of the operator when he desires to withdraw the tongs from the block or other work. It will be noted from Figure 5 that the heads o! the blocks 35 are embedded in the rubber blocks s2 in substantial spaced relation from the inner walls of the rubber jaws 32 which grip the object in order to allow for adequate compression of the inner portions of these rubber blocks 32 without bringing the bolt heads 35 into contact with the surface of the work.

By loosening the lock nuts Il and I8, the screw I6 may be pushed in vor out with respect to the yoke 33 oi' the cross bar I2 and thus shift the fulcrum support I5 toward or from the fixed leg Ill. `After adjustment the lock nuts Il and I8 are retightened against the yoke 33. By such adjustment the movable leg jaw may be shifted toward or from its companion jaw carried by the fixed leg I@ and thus the span of the device may be increased or diminished to compensate for different distances between the walls of the article to be gripped. This adjustment is also eilicacious in determining the .amount ol' compression to which the rubber blocks are to be subjected.

The series of apertures 22 also provide for the adjustment of the toggle lever in its connection with the upper end 0f the lever leg II. This permits the handle or toggle lever as to its distance between the pivots 25 and 26 to be lengthened or shortened. This latter adjustment may accompany ii desired any adjustment eiected in the fulcrum support I5 by means of the screw I6 and the look nuts I1 and I8. Either adjustment may be made independently to suit various conditions. Both adjustments will probably be found desirable where attempt is made to preserve the parallel relationship between the inner faces of the two rubber blocks 32 when the same are in the closed position oi Figure 2.

Although both legs I0 and II might oe made pivoted, it is preferred that the leg- ID be sta tionary with respect to the other elements of the device, particularly where its use in connection with cement blocks is concerned inasmuch as the straight leg I0 is always more easily inserted downwardly through the vertical air passage in the hollow cem-ent block while a diagonally disposed pivoted leg II (see its position in Figure 3) is more diillcult to insert into such air passage of the cement block. Thus by having one straight leg IIJ and only one diagonal leg it is much easier to assemble the tongs to the cement block than if both the legs were diagonally disposed into open position of the tongs.

In handling the ordinary cement block on the outer edge very frequently the fingers are mashed against the block already set. To avoid this the block is usually lowered to the mortar about 1" or 11/2 to the set block and is then pushed against the block that is set. Quite a bit 0I' mortar is thereby pushed into the openings in the block below, and necessarily the block is lowered from 1/8 to 1A because of the loss of mortar on the underside of the block being laid. With these tongs thatgrpin the middle, the block can be laid within 1/2" of the other block and need not be moved at all.

It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the folowing claims.

I claim:

1. A lifting tongs comprising a pair of legs having jaws at one end, a bar connecting intermediate portions of the legs, a fulcrum on the bar on which one leg is pivoted, and a toggle lever comprising a tubular handle member having :a slot at one end of its upper portion and a stop below the slot, said tubular member pivoted to one leg, and an inferi-or toggle member pivoted to the other leg and to the tubular member within said slot and adapted to encounter said stop in the locked position of the toggle lever.

2. A lifting tongs comprising a pair of legs having jaws at one end, a bar connecting inter- REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 661,033 Brownfield Nov. 6, 1900 705,416 Martin et al July 22, 1902 806,672 Hunziker Dec. 5, 1905 1,014,079 McKay et al Jan. 9, 1912 20 1,212,822 Schlepp Jan. 16, 1917 1,413,225 I-Iemstreet Apr. 18, 1922

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