US2507368A - Lifting tongs for concrete blocks - Google Patents

Description

May 9, 1950 G. CARLSON 2,507,368

LIFTING ToNGs FoR CONCRETE BLOCKS Filed Feb. 24, 1947 (5l/STAP CARLSON Gi/5?@ I FFF@ ATTOENEYS Patented May 9, 1950 LIF'IING TONGS EUR CONCRETE BLOCKS .Gustaf 'Carlson, Minneapolis, ,Minn., fassignor to Arko Tool d: Die-Company, Minneapolis, Minn., fa partnership composed of .Gustaf -Carlson-and Gilbert H. V4Holmnson Appncanoarepmary 24, 1947, sei-iai No. Y730,241

(creci- 106) fl-Claims. :l

This invention `Irelates to new 'and useful Aimprovements'in lifting tongs, and more particularly to'such devices adapted vfor lifting concrete -blocks in -the building trade-although itis .to'be understood that Ythey may be utilized vforiliitin'g other-articles, where applicable.

`Prefabricated Lconcrete blocks are .now commonly used A,in the buildin-g art 1in the construction Lo'fioundations and building walls. These blocks are iusually "placed one upon another .in horizontal ftiers .with sa Llayer :or mortar :being Vinterposedbetween adjacent'blocks to firmly bind them ltogether and lto prevent leakage .between theblocks. VV-In'the constructionfof a walhalthin layer of mortar is usually placed .upon the rows of blocks as they 4are successively/laid in the vwall and as themortar-is comparatively soft, the 4concrete "blocks mustbe 'carefully laid into place 1in 'the Wall so as not to disrupt the layer of mortar placed Von the previously 'laid iblocks. 'In 'other words, to obtain a good joint beiaveen adjacent blocks, leach block as it is laid into place, should A*be 'held in Ia horizontal lposition -so that .its ibut- 'tom vface will engage `the mortar Ysubstantially over its entire ar-ea, and at the same Vtime the '-block'is -gently shoved into contact with the mortar applied vto the adjacentendof the previously laid 'block in `a given tier, whereby :the layers of mortar rbetween the horizontal and upright faces of adjacent blocks "will besubstantiallyvuniform v`in thickness. '-It is rather zdiihcult .to handie concrete blocks by hand, particularly the larger sizes,'and it fis, therefore, the purpcsel-of this invention to provide a Vsimple-device adapted to be used by a stone mason for other workman 'to grasp concrete `"blocks, lwhereby -the operation of constructing a wall loi concrete 'blocks imay b'e greatly'facilitated.

The novel 'tongs 4herein Y'disclused is :showncompris'in'g a supporting shaft lhaving 'two sets aci jaws pivotally mounted thereon, vone set at each end of the shaft. The :handle Yportions of sait] ,pairs of jaws are so designedtha'tthe-y may -readily be grasped 'by one 'han-'d whereby Vwhen the composite device is used-to grasp aconcrete block Y or .other article, the jaws will 'engage the block with uniform pressurawhereby they may readily expeditiously place the blocks in position in a wall without danger of vdisrupting `:the layers of mortar applied to the 'previously laid blocks.

It iis, therefore, an object of the presen-t invention Y"to provide a 4simple and inexpensive li-ft- `'ing device jfor (concrete blocks, and the like, whereby a stone mason `orworkman may :quickly and with a minimum yof effort, 4pick 'up `the fcon- 255 crete blocks and pla-ce ythem in proper position in fa wall `without disrupting the layer of mortar placed between adjacent blocks, thereby 'mak- 'ing'it possible to construct a concrete block wall in a comparatively short period of time and vwith the assurance that the joints between adjacent blocks will be substantially weatherproof.

`A further object of the invention is to provide a lifting device of the class described comprising spaced-apart pairs of jaws, andthe corresponding jaws of Aeach pair'of jaws being 'connected together Vby suitable `tie rods which cooperate to provide a handle which may be vreadilygrasped 'by 'the hand of an operator, thereby to simultaneously manipulate al1 of said jaws to grasp a concrete block or other article to facilitate moving `it from one place to another.

A further object is to provide a device of the class described comprising a supporting Yshaft having a pair of jaws mounted at each .end thereof, and the jaws of each pair of ljaws being .provided with means cooperating to provide an operating handle which may be readily grasped by a mason or workman, and means being yprovided whereby the spacing ibetween said pairs of jaws may be varied in a direction lengthwise of the supporting shaft, thereby to adapt the device for liftingblocks or articles of different sizes.

Other objects of the invention reside in the simple and inexpensive construction of the tongs whereby they may be manufactured in quantity production at low cost; in the provision of such a device which comprises coacting pairs of jaws adapted simultaneously to engage and grasp an .object lwhenthe handle of said jaws is grasped by a workman; in "the means embodied inY said device whereby all fof the jaws ythereoi will grip the hlock `or article with uniform pressure to assure a 'positive grip on the block; :and in the provision :of such a device which is lextremely eihcient and :practical fin operation, and by the vue of which the operation of Asuccessively laying concrete blocks kin `a wall is Agreatly facilitated.

--Otherfobjectsof the `invention will appear from thefo'llowing description and the accompanying drawings and will 'be pointed vout inthe :annexed claims.

vIn 'the accompaniyng drawings there `has lbeen disclosed :a vstructures Adesigned vto carry out vthe various objects of the invention, but it is to be understood kthat the .invention .iis not confined Ito the exact features shown,-as'variouschanges may f'be made 'within the scope fof the v`claims which In the drawings:

Figure 1 is a perspective view of the device showing the jaws opened as if to grasp a block or other object;

Figure 2 is a view showing a conventional concrete block in longitudinal section, with my improved lifting tongs applied to each end thereof, the tongs at the left being shown with the jaws open;

Figure 3 is a detail sectional view on the line 3-3 of Figure 2, showing the jaws adjusted for a large block;

Figure 4 is an end view of Figure 2 showing only a portion of the concrete block;

Figure 5 is a view corresponding to Figure 3, but showing the jaws positioned for engaging a relatively smaller concrete block; and

Figure 6 is an end view of Figure 5.

The novel tongs herein disclosed are shown comprising spaced apart pairs of tongs, generally designated by the numerals 2 and 3. The tong 2 is shown comprising complemental jaws 4 and 5 having bearing portions 6 and l, respectively, which are shown pivotally mounted on a reduced terminal 8 of a suitable supporting shaft 9. The reduced terminal Il is further reduced to provide a threaded end portion Il adapted to receive a wing nut I2, or other suitable nut, for pivotally retaining the jaws It and 5 on the terminal portion 8 of the shaft 9.

The jaws 4 and 5 are provided with operating levers I3 and M, respectively, which have their upper ends suitably secured to the adjacent ends of a pair of tie rods I5 and I6, as Ibest shown in Figure l. The tie rods I5 and i5 have reduced threaded end portions Il received in suitable apertures provided in the upper ends of the levers I3 and i4 adapted to receive suitable nuts I8 whereby the levers may be secured to the tie rods I5 and I6.

The tongs 3 at the opposite end of the supporting shaft 9 are shown comprising complemental jaws I9 and 2i which are similar to the jaws 4 and 5, and have operating levers 22 and 23, respectively, as shown in Figure 1. The upper ends of the levers 22 and 23 are secured to the oiset ends of the rods I5 and I6 in a manner similar to the levers I3 and I4 of the opposite ends thereof whereby the jaws oi the two pairs of tongs 2 and `3 are operatively connected together for simultaneous operation. The levers 22 and 23 are pivotally mounted on the supporting shaft 9 in a manner similar to the levers i3 and Il! at the opposite end thereof.

The connections between the tie rods I5 and I6 and the levers I'3, M, 22 and 23 are preferably such that when the device is grippingly engaged with a concrete block, as shown at the right hand end of Figure 2, all of the jaws 4, 5, I9 and 2l will grip the block with uniform pressure, even though the surfaces of the block which are engaged by the jaws may be more or less uneven. Such uniform gripping action of the jaws may readily be obtained by making the connection between the rods I5 and I6 and the levers slightly loose, the nuts I3, however, being inseparably secured to their respective rod ends I1.

One of the important features of the present invention resides in the arrangement of the jaws with relation to their respective operating levers. By reference to Figure 3, it will be noted that the jaws 4 and 5 are disposed in a plane 1 -a, spaced outwardly from the median plane b-b of the bearing portions 6 and l of the jaws. In like manner, the jaws I9 and 2| are disposed in a plane a-a spaced outwardly from the median plane b-b of the bearing portions of said jaws. By this arrangement it will be noted that the spacing s between the two pairs of jaws is relatively greater than the spacing s between the operating levers of the two pairs of jaws.

By so osetting the jaws from their respective operating levers, the lifting tongs are readily adaptable for handling building blocks of diiferent sizes by simply interchanging the jaws at the two ends of the supporting shaft il, as will be understood by reference to Figures 3 and 5.

In Figure 3 the jaws are positioned for handling relatively wide concrete blocks, whereas in Figure 5 the jaws of the two pairs of tongs 2 and 3 have been interchanged to decrease the spacing s between the two sets of jaws for handling relatively smaller concrete blocks, as will be readily understood.

To interchange the jaws, as above described, it is only necessary to remove the nuts I8 from the tie rods I5 anl I6, and the wing nuts l2 of the supporting shaft 9. rI'he entire device may then be readily taken apart after which the two sets of jaws may be interchanged, as will be understood by reference to Figures 3 to 6, inclusive. rI'he oisetting of the jaws from their respective levers is such that the same supporting shaft and tie rods I5 and IE may be utilized regardless of whether the tool is adjusted for handling large blocks or small blocks, it being understood that the spacing s between the operating levers of each pair of jaws or tongs is always constant.

The tongs are preferably used as indicated in Figure 2. That is, the operator when handling large blocks will grasp the block at each end thereof with two separate pairs of tongs, one for each hand. The tongs are usually engaged with the cross ribs or members 25 and 2S provided at the ends of the block, as shown in Figure 2, and as is well known in concrete block construction. The shape of the jaws in relation to the operating levers is such that the firmer the operator grasps the tie rod handles I5 and I5, the tighter the jaws will grip the wall portions 25 and 26 of the concrete block, whereby the operator may readily and conveniently slip the block into proper position in the wall Without danger of distorting or disrupting the soft mortar upon which the block is to be placed.

It will be apparent to those skilled in the art that I have accomplished at least the principal objects of my invention, and it will also be apparent to those skilled in the art that the embodiments herein described may be variously changed and modified without departing from the spirit of the invention, and that the invention is capable o uses and has advantages not herein speciically described; hence it will be appreciated that the herein disclosed embodiments are illustrative only, and that my invention is not limited thereto.

I claim as my invention:

1. In a device for lifting concrete blocks of different sizes, a supporting shaft, a pair of levers pivotally mounted on each end of said shaft, each lever having a work-engaging jaw, and the jaws of each pair of levers being laterally offset from their respective levers and disposed in a common plane, tie rods connecting together the corresponding levers of said pairs of jaws and cooperating to provide a lifting handle whereby'the jaws may be conveniently manipulated to grasp a concrete block, and means whereby the two pairs of jaws may be interchanged on the supporting shaft to vary the spacing between said pairs of jaws to adapt the device for handling concrete blocks of different sizes.

2. In a device for lifting concrete blocks of different sizes, a supporting shaft, a pair of levers pivotally mounted on each end of said shaft, each lever having a work-engaging jaw, and the jaws of each pair of levers being laterally offset from their respective levers and disposed in a common plane, tie rods connecting together the corresponding levers of said pairs of jaws and cooperating to provide a lifting handle whereby all of said jaws may be conveniently manipulated to grasp a concrete block, and said rods having movable connections with their respective levers whereby all of said jaws will grasp the block with uniform pressure.

3. In a device for lifting concrete blocks of different sizes, a supporting shaft, a pair of levers pivotally mounted on each end of said shaft, each lever having a work-engaging jaw, and the jaws of each pair of levers being laterally offset from their respective levers and disposed in a common plane, tie rods connecting together the corresponding levers of said pairs of jaws and cooperating to provide a lifting handle whereby all of said jaws may be simultaneously operated to grasp a concrete block, means whereby the two pairs of jaws may be interchanged on the supporting shaft to vary the spacing between said pairs of jaws to adapt the device for handling concrete blocks of different sizes, and said rods having movable connections with their respective levers whereby al1 of said jaws will grasp the block with uniform pressure.

4. In a device for lifting conventional concrete blocks each comprising opposed side walls connected together by a plurality of cross walls, a'. supporting shaft, a pair of levers pivotally mounted on each end of said shaft and having tie rods connecting together the upper ends; thereof and cooperating to provide a handle for' actuating the levers, each pair of levers being. provided at their lower ends with work-engaging jaws which are oiset from their respective levers the saine direction, whereby the jaws of said of levers may be spaced apart to engage a cross wall of a concrete block adjacent the sidey wails thereof, and means whereby the jaws may be reversed to vary the spacing therebetween whereby the device may be utilized for transporting concrete blocks of different sizes.

GUSTAF CARLSON.,

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

UNITED STATES PATENTS Number Nai'ne Date 74,514 Davidge Feb. 18, 1868 905,010 Simmons Nov. 24, 1908 1,974,255 Behrendt Sept. 18, 1934 FOREIGN PATENTS Number Country Date 168,592 Switzerland 1934

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