USRE17597E - By byron jackson - Google Patents

Description

Feb. 18, 1930. a. ADAMS MULTIPLE SI ZE TONGS Original Filed Nov. 11, 1924 2 Sheets-Sheet l Inventor fiflertflaams dereas ea y Byron .flssg'yzzee Feb. 18, 1930. R. ADAMS MULTIPLE SIZE TONGS Original Filed Nov. 11, 1924 Z'Sheets-Sheet 2 M5. deceased Reieaued Feb. 18, 1930 UNITED STATES PATENT OFFI ROBERT ADAMS, DECEASED, LATE OF LOS ANGIE-LES, CALIFORNIA, BY BYRON JACKSON COL, ASSIGNEE, OF LOS ANGELES, CALIFORNIA Original in, 1,652,551,

MULTIPLE-SIZE 'IONGS This invention has to do with tongs that are adaptable to work of different sizes; and the general object of the invention is to make such tongs have a work gripping or contacting surface that will give a good, broad and comparatively flat engagement with different sizes of work.

Heretofore, in tongs that have been adjustable or, in some manner, applicable to take pipe or other work of different sizes, the work engaging members have been so formed on their work enga 'ng surfaces that it has been impossible to o tain a good contact with more than one size' of pipe. For instance, in tongs where the work 1s enclrcled by several interconnected jaws or segments; those jaws or segments have commonly been formed or bored to have arcuate surfaces of a certain diameter, and that would accordingly fit flatly only upon a single diameter of work. On work of all other diameters there has thus been practically only a point or line of contact of each segment or jaw with the work.

This invention comprises primarily the formation ofwork engaging surfaces in such a manner as to give a comparatively broad "and flat engagement with any size --of work to which the tongs are adapted. In explaining the invention, in the following description, it is applied specifically to that type of tongs known as the Wilson tongs, which are largely used in oil well work. Thus the invention is explained as applied to such tongs as are set out in the patents to Elihu C. Wilson, Patent No. 1,561,963, dated November 17, 1925, and Patent No. 1,575,141, dated March 3, 1926, and the patent to BobertAdams, Patent No. 1,647,977, dated N vember 8, 1927. But it will be understood that the explanation of the invention as applied to such specific type of tongs is not to be taken as a limitation upon the invention i self. v

For the purposes of the description, there is shown in the accompanying drawings such tongs with the invention applied thereto, and in these drawings:

Figure 1 is a plan showing the tongs close about a smaller pipe;

dated December 13, 1927, Serial No. 749,126,11led November 11, 1924. Application for reissue filed December 10, 1929. Serial No. 413,131.

Fig. 2 is a plan, with parts in section, showing the tongs closed about a larger pipe;

Fig. 3 is a plan, with parts in section, showing the tongs equipped with reducing bushings, and applied to the larger size of pipe that it will take when equipped with such bushings;

Fig. 4 is a detailed section on line 44 of 3;

Fig. 5 is a more or less diagrammatic section showing more clearly the. formation of the work engaging surfaces; and

Fig. 6 is a diagram showing a modified form of work engaging face.

. The specific type of tongs, shown in the drawings involve a lever handle 10 with a plurality of pipe encircling segments or aws, so pivoted to the handle that movement of the handle constricts the jaws about the work. Thus, for instance, the handle has two pivots at 11 and 12, to which the jaws 13 and 14 are connected, and these two jaws 13 and 14 carry two outer jaws 15 and 16 pivoted to them at pivots 17 and 18. One' of the outer jaws carries the spring pressed latch 19, whose latchin shoulder 20 is adapted to engage either 0 two lug shoulders 21 and 22 on the other outer aw 16. By the latch thus engaging either of the shoulders, and also by vided with pipe engaging surfaces of two curvatures. Thus, for instance as on the jaw 15, it will be noted that the curvature between the two dash lines aa and bb,j is a curvature corresponding to that of the smaller pipe P, whereas the curvature from line aa and line bb to the ends of the jaw is a curvature corresponding to that of the larger size pipe or collar C. These two curvatures are, in practice, formed as follows: The tongs are first set in the position shown in Fig. 2, that ioo is, in a position to encircle the larger size pipe or collar, and then the inner faces of the jaws are bored out to a diameter equal to that of the larger size pipe or collar. In this COIldltion the jaws have but a single curvature, the jaws having curved faces that would then fit flatly upon the larger size pipe or collar' throughout the lengths of the jaws. Then the tongs are put into the position shown 1n Fig. 1, that being the position they assume when surrounding the smaller size pipe P. In this position they are bored to a diameter I equal to the smaller size pipe, but in so boring it will be notedthat the cutting tool does not cut into each jaw throughout the length 7 of its face, but only cuts into the central part of each jaw so that there is then in the center of each, jaw a curved face of a curvature correspoi'idlng to that of the smaller size pipe, leaving intact the two endfaces of each jaw that have curvatures corresponding to the curvature of the'larger size pipe or collar. Thus, when the tongs are applied to the smaller size pipe, the jaws each seat on the pipe flatly throughout those portions of their faces that are of the smaller diameter curvature; while, when the tongs are applied to the larger size pipe or collar, they contact and seat flatly throughout those portions that have curvatures on the larger. diameter.

It will, of course, be readily understood that the scheme of curvatilres here described is not limited necessarily to curvatures of I only two diameters, as it will be obvious that in tongs applicable to three or more different diameters of work, the jaw faces may be bored or'otherwise surfaced to have curvatures on those three or more different diameters. However, as theinvention .is here described as applied to a tongs applicable to two differ- .ent sizes of work, the jaws are shown with two different curvatures.

'The tongs shown in these drawings may be adapted to take other different sizes of work by the use of bushings B such as shown in Figs. 3 and 4. These bushings may be made easily attachable to and detachable from the tongs as, for instance, by being held in place by cap screws 30, and they are curved at their back faces to seat back against the face curvatures of the jaws. For instance, a simple way of making the bushings is to make the curvature of their back faces the same as the smaller diameter curvature of the jaws. The front or inner faces of those bushings may also have surfaces of multiple curvature, in

this case faces of double curvature. For instance,'in these bushings the curvature between the two lines a-a and b-b may be the curvature to take a smaller size pipe P as is indicated in Fig. 5, while the curvature between said lines aa and bb and the ends of the bushings may be such as to, take a larger size pipe or a collar C, as is shown in Fig. 3.

The bushings thus enable thetongs tobe used on dpipes or collars of various difierent sizes, an

of course, several sets of bushings of different thicknesses may be applied and used in connection with a given set of tongs. But another advantage of the bushin is in thls: that by theuse of such bushings t e tongs may be made to accurately fit upon a pipe of a diameter very slightly different from the pipe which the tongs will fit without the bushings. In a tongs of the kind here illustrated, it is advantageous to have the two lug shoulders 21 and 22 spaced apart by a substantial distance in order to make the latch shoulder always drop over and engage with the correct lug shoulder when the tongs are applied to a pipe without the necessity of the correct shoulder being selected by the operator. Tongs of the character herein shown are made to be automatic in their application to a plpe,

.as is set out in the Adams patent hereinbe-. forementioned. '.In' such operation of the tongs the handle 10 is'thrown around in the direction indicated by-thearrow in Fig. 1, until it contacts with the By holding the handle in this position, jaw 13 is prevented from backing away from the pipe and the stop action of stop lug 36 on jaw 13 and lug 37 on jaw 15 limits the-amount by which jaw 15 can back away from thepipe. With the parts in this position it is only stop 35 on jaw 13;

necessary to swing the jaw 16 around to closplied to the larger size pipe or collar. Consequently, in a tongs of this type, it may be somewhat diflicult to have the tongs applicable to pipes of different sizes where the difference in size is comparatively slight. But by the use of bushings it will be seen that, for instance, the larger size pipe or collar which may betaken by the tongs equipped with bushings may be very nearly the size of the smaller size pipe that may be taken by the tongs not equipped with bushings; and that in each case the tongs makes very good contact with the pipe or collar, as the case may be.

Fig. 5 shows, more or less diagrammatically, the different curvatures of the work gripping surfaces. Here the difference in curvatures is made clear and it is made clear how only surfaces of one curvature will contact and grip with a pipe of a given diameter, and that a flat contact is had over a considerable area. In Fig. 5 a smaller size pipe is shown and it will be seen that it is gripped over the area between the lines aa and bb.

This area on the bushing B (and likewise the corresponding area on the jaw) has a cylindric curvature with a center at the point a. The surfaces at the ends of the bushing and jaw are of a cylindric curvature whose center is at the point 0 The small sized pipe will engage only the curved surface be tween lines a-"a and b-b. Similarly the larger sized pipe will engage only the curved surfaces outside those two lines, clearing the curved surface of shorter radius. This is because the short radius surface lies outside the curvature (prolonged) of the large radiussurfaces, as will readily be seen from the drawings.

If it were desired to' make these surfaces adaptable to another and still smaller size of pipe, a surface of another curvature would, for instance, be made as indicated by the dotted lines 8 having a center, for instance, at the point 0 Carried to an ultimate conclusion, this provision of surfaces of different curvatures on the faces of the jaws or segments amounts to the pipe gripping face of any one jaw having a varying curvature. In other words, it amounts to the jaw, for instance, having a face of a curvature thatvaries from point to point along its length. If the curvature from end to end of the jaw constantly varied, in strict theory there would be, of course, but a line of contact with each individual size of pipe. But, if the variation in curvature is not very great, in practice, due to resilient compressibility of the materials of the jaws and pipe, this theoretical line of contact isexpanded into a small surface of contact. Thus, for instance, the jaw may be equipped with an inner face, such as illustrated in Fig. 6. Here, for instance, the inner face F may be parabolic in contour and the curvature, saat the points p, may be on a diameter of 6 while the curvature at the center point 1) may be, for instance, on a diameter of 5 A pipe of 6 diameter would theoretically contact at the two points 11, while a pipe of 5" diameter would contact at the point p; but the variation in curvature being small, the theoretic lines of contact are expanded into small areas of contact by reason of resilient compressibility of the materials. a

However, the specifically preferred form of gripping surfacethat involves a plurality of surfaces of different curvature, the curvature of each individual surface being uniform; as has been first explained in this description. In such an arrangement, if it is desired to use toothed dies, such as are com-' monly inset into tong jaws, those toothed dies are inset into one or more of the jaws at the points of change of curvature in their surfaces. This, for instance, is illustrated at D in Figs. 1 and 5. In such position it will be What is claimed is:

1. In a tongs, the combination of a plurality of work gripping aws adapted collectively to surround and grip work of differentsizes, the jaws having substantially similar work engaging faces and each jaw having work engaging surfaces of two different curvatures, and means selectively to interconnect the jaws either in position such that their surfaces of lesser curvature lie substantially in a single circular periphery or in position such that their surfaces of greater curvature lie substantially in a single smaller circular periphery.

2. In a. tongs, the combination of a plurality-of work-gripping jaws adapted collectively to surround and grip work of different sizes, the jaws having substantially similar work engaging faces and each jaw having work engaging surfaces of two different circular curvatures, the surface of greater curvature lying outside the curvature, prolonged, of the surface of lesser curvature, and means selectively to interconnect the jaws either in position such that their surfaces of lesser curvature lie substantially in a single circular periphery or in position such that their surfaces of greater curvature lie sub-' stantially in a single smaller circular periphery.

3. In a tongs, the combination of a plurality of work gripping jaws adapted collectively to surround and grip work of different sizes, thejaws having substantially similar work engaging faces and each jaw having work engaging surfaces of two different curvatures, and means selectively to interconnect the jaws either in position such that their surfaces of lesser curvature lie substantially 1n a slngle circular periphery or in position such that their surfaces of greater curvature ing between adjacent ends of two adjacentaws. I

4. In a tongs, the combination of a plu-* rality of work gripping jaws adapted collectively to surround and grip work of different sizes, the jaws having substantially similar work engaging faces andeach jaw having work engaging surfaces of two different circular curvatures, the surface .of greater curvature lying outside the curvature, prolonged, of the surface of lesser curvature, and means selectively to interconnect'the jaws either in position such that their surfaces of lesser curvature lie substantially in a single circular periphery or in position "such that their surfaces of greater curvature lie substantially in a single smaller. circular periphery, said means embodying a multiple step latch device mounted upon and operating between adjacent ends of two adjacent jaws.

5. In a tongs, the combination of a plurality of work gripping jaws adapted collectively to surround and grip work of different sizes, one of said jaws having a work-engaging surface of a plurality of differentcurvatures, and of which a surface of greater curvature lies outside the curvature, prolonged, of a surface of lesser curvature; and means selectively to interconnect the jaws either in position that such surface of lesser curvature 1o lies substantially in a single circular peripherg with the work engaglng surfaces of the ot er jaws, or in a poslition that such surface 5 of greater curvature ies substantially in a single smaller circular periphery with the work engaging surfaces of the other 'aws.

6. In a tongs, the combination 0 a, Inralityof work gripping jaws adapted co ectively to surround and ip work of difl'erent sizes, one of said jaws living a work engag- :0 ing surface of a plurality of different-curvatures, and of which a surface of greater curvature lies outside the curvature, prolonged of a surface of lesser curvature; and means selectively to interconnect the jaws either in position that such surface of lesser curvature lies substantially in a single circular peripherlyl with the work engaging surfaces of the ot er jaws, or in a position that such surface of greater curvature lies" substantially in a single smaller circular periphery 'with the work engagin surfaces of the other jaws, said means emlrodying a multiple step latch 1 device mounted upon and operating between adjacent ends of two adj acent jaws and hav- YF ing latch steps equal in number to the number of said different work en agin curvatures.

Signed this 21st da 0 Octo e'r,'192 9. [It s.] BYR N JACKSON C0 By. W. W. WILSON,

Vice President, For Robert Adams, Deceased and as A8- signeeof the Entire Right, iz'tle, and Interest.

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