US2740311A - Expanding jaw screw extractor - Google Patents

Description

April 3, 1956 T. c. TEDE, 2,740,311

EXPANDING JAW SCREW EXTRACTOR Filed July 21, 1 954 Zij 1L @529 2f l@ 19 "$2 5 1/0 N j Z2 l l. l, 337W i gg IN V EN TOR.

nite States arent EXPANDING JAW SCREW EXTRACTOR Thomas C. Tedei, Franklin Park, Ill.

Application July 21, 1954, Serial No. 444,718

3 Claims. (Cl. 81-72) This invention relates, in general, to screw appliers and extractors, and more particularly to a tool for removing the embedded parts of pipes, pipe nipples, bushings, solder bushings, broken pipe threads, and other parts, such, for example, as plumbing and steam litting parts which have had their heads or outer portions broken or twisted without leaving a projection suliiciently long to enable removal in the usual manner.

The tool of the present invention is also adapted for use by mechanics, tool and die men, and elsewhere, as desired, for removing and/ or applying other parts.

Devices of the character to which the present invention relates have usually consisted of a tapered operating portion provided with helical ribs for engagement with the metal or other material of the part to he extracted and disposed reversely with respect to the threads of said part with intermediate iutes or grooves therebetween. These tools have been open to objections; in the first place, one such tool has been adapted for use with only one size of pipe, pipe itting, nipple, bushing or other threaded part. Therefore, for example, for seven or eight sizes of pipes, pipe tittings, nipples, bushings or the like, a corresponding number of such tools have been required. This increases the cost and introduces complications in selecting and accommodating the various sizes of tools to the various sizes of pipes, pipe ittings, nipples, bushings and the like.

In the second place, the strength of the aforementioned type of tools has not always been suiiicient to enable them to resist the torsional stresses incident to normal use.

One of the main objects of the present invention is to provide an improved form of tool of the character described which is adapted for use with a relatively large number of dierent sizes of pipes, pipe fittings, nipples, bushings and the like and which may be more positive and certain in action as well as stronger than prior tools of the aforementioned character.

Another object is to provide a tool with which more force may be applied to the pipe, pipe tting, nipple, bushing or the like for removing the same from the part into which it is screwed.

Another object is to provide a tool of this character which is less expensive for a plurality of pipes, pipe iittings, nipples, bushings and the like of diterent sizes and which is of simple and practical construction, eliicient, easy and reliable in operation, relatively inexpensive to manufacture, and well adapted for the intended purpose.

Further objects and advantages of the invention will appear from the following detailed description taken in connection with the accompanying drawing showing one embodiment of the invention, it being understood that the invention is limited only within the scope of the appended claims and not to the particular embodiment selected for illustration.

In the drawing:

Figure l is a side elevational view of my improved extractor partially broken away and in section showing the jaws in closed position in full lines and with one jaw shown in dotted lines in its open or separated position with respect to the other jaw;

Figure 2 is a top planview taken on theline 2 2 of Figure l;

Figure 3 is a bottom plan view taken on theline 3 3 of Figure 1; t

Figure 4 is a fragmentary view of the left hand end of the device as shown in Figure l with the jaws separated and showing the manner in which the edges at the angles or corners of the stepped portions for one size of pipe, pipe fitting, nipple, bushing or other threaded part bite into the interior of such part for removing the same from a part into which it is screwed; and

Figure 5 is an end view taken on theline 5 5 of Figure l showing in dotted lines the jaws separated into engagement with the part to be removed and a wrench applied to the sides of the jaws intermediate the ends thereof for turning same to remove the threaded part.

Referring now to the drawing, the embodiment of the invention therein illustrated comprises a pair ofjaws 1 and 2 each in the form of flat bar having opposite atparallel sides 6 6, and intermediate liat top andbottom surfaces 7 7 normal or at right angles to thesides 6 6.

At the left hand end of the device as shown in Figure l, the jaws l and 2 have steppedportions 8 8, 9 9, and 1li-10 and at the right hand end the jaws have stepped portions 11-11, 12 12, 13 13, and 14 14. The stepped portions afford diiferent size portions of substantially polygonal configuration for entry into ditferent sizes of pipes, pipe fittings, nipples, bushings or other threaded parts. For example, the stepped part 14-14 may enter a tubular or hollow threaded part of 3/s internal diameter whereas thestepped portions 13 13, 12 12, 11 11, 10 10, 9 9, and 8 3 may enter tubular or hollow threaded parts of 1/2, 3A, 1", 1%", 11/2, and 1% internal diameter and the top andbottom surfaces 7 7 may enter a tubular or hollow threaded part of a larger internal diameter. The foregoing sizes and the number of different size parts with which the tool may be used are merely illustrative and the invention is not in any way limited to the sizes or the number of different size parts with which the tool may be employed` Taking,I for example, thesteppedl portions 8 8 which are shown in Figure 4 entered into a pipe, pipe fitting, nipple, bushing or other threadedpart 15, these steppedportions 8 8 are of substantially polygonal configuration withedges 16 at the corners or angles thereof for biting engagement with the part l5 to be extracted. The other stepped portions and the intermediate portions of thejaws 1 and 2 are of similar polygonal conliguration but of different sizes and have similar edges at the corners or angles thereof for biting engagement with parts of dierent sizes.

Means operable to separate thejaws 1 and 2 to expand theedges 16 of the polygonal stepped portions into biting engagement with the interior of the threaded part and to permit the jaws l and 2 to be closed or contracted for insertion and removal of the stepped portion from the part to be inserted or extracted comprises a pair ofscrews 1S 18 having screwed or threaded engagement inopenings 19 19 which open transversely through the jaw 1. rl`he outer ends of thescrews 13 18 have kerfs orpolygonal sockets 21 for engagement therein, for example, of an Allen wrench for screwing the screws 1S inwardly or outwardly with'respect to the jaw 1. The innertapered ends 22 of thescrews 18 are adapted by engagement with thesurface 23 of thejaw 2 to separate this jaw from the jaw l to open position as shown in Figure 4 and in dotted lines in Figures l and 5. This expands theedges 16 of the stepped portions with great force into biting engagement with the interior of thepart 15. Then, for example, with a flat crescent wrench or other suitable wrench applied to the fiat sides of the intermediate portions of the patented Apr. 3, 1956t jaws 1 and 2 as shown at 22 in Figure 5 these jaws are turned about the axis of the stepped portions` to` screw the part into or from the part with which it has threaded engagement.

The opposed' jaw surfaces at 23- are preferably oiset laterally from the opposed end surfaces 245 totorm on the jaw 2 a tenori-likelateral projection 25 which is guided for sliding movement in a mortis-like cavity 2.6 in the jaw 1. The ends of the tenen-like projection by cooperation with the jaw 1 at the ends of the mortis-like cavity 26 maintain the jaws properly related and take such end thrusts as may be imposed.

Guide pins 28-28 have tight pressed ht or are otherwise lixedly secured at 29 in openings in the jaw 1 and ex-` tend loosely throughopenings 30 in thejaw 2 and guide this latter jaw in its opening` and closing movements.

Separation of thejaw 2 from the jaw` 1 is limitedl by engagement of the head31 ota pin 32 with the inner end 33 of a socket 3:4-n thejaw 2. When the jaws are closed, the outer end of thehead 31 is substantially tlush with thebottom surface 7 of thejaw 2. The pin 32 extends loosely through an opening in theljaw 2 for sliding movement of this latter jaw thereon. The opposite end of the pin 32 is further reduced and screwed at 35 intoy a threaded opening in the jaw 1. Thehead 31 of the pin 32 has a kerf orpolygonal socket 36 for engagement therein, for example, of an Allen wrench for screwing the threaded end of the pin 32 into the jaw 1.

Thejaws 1 and 2 according to the present invention are adapted'to be cut from steel bars, for example, by a drop forging operation or they may be machined to shape if desired. Upon completion of the jaws, they are preferably tempered in an oilV tempering bath to case harden the jaws. The guide pins, stop pin, andscrews 18 may also be case hardened.

The use of flat bars facilitates forming the jaws and these bars provide thesharp edges 16 at the corners of the polygonal shaped stepped portions whichprovide-effective and improved biting engagement with the part to be inserted or extracted when the jaws are opened with powerful force by thescrews 18. The tool is quickly adaptable to pipes, pipe iittings, nipples, bushings and the like of dierent sizesv and for such part of any size the tool is engaged therewith expeditiously and with great force for effective and certain action.

The embodiment of' the invention shown in the drawing is for illustrative purposes only and it is to be expressly understood that said drawing and the accompanying speciication are not to be construed as a definition of the limits or scope of the invention, reference being had to the appended claims for that purpose.

I claim:

l. A screw extractor comprising a pair of tlat jaws rectangular-shaped in transverse section and having coplanar flat sides arranged to be gripped by a wrench for turning said jaws about the longitudinal axis thereof, said jaws having at one end stepped down portions affording different size portions rectangularl'shaped in transverse section for entry into externally threaded tubular parts of diterl jaw to guide said other jaw in its movement away from' and toward said one jaw, and a stop pin carried by said one jaw and extending into an opening in said other` jaw and provided with an enlarged head engageable with said other jaw to limit separation of said other jaw from Ysaid one jaw. j j'j 2. A screw extractor accordingto claim l wherein one of the jaws has a tenon-like projection having sliding movement in amortise-like cavity'in the other jaw to maintain said jaws in alignment and take such longitudinal thrusts as may be imposed on said'jaws;

3. A screwl extractorA comprising a'pair of flat jaws rectangular-shaped in transverse section and having, coplanar at. sides arranged to be gripped by'a wrench for turning said jaws` about the longitudinal axis thereof, said jaws having at one end stepped down portions altording different size portionsl rectangular-shaped in transverse section forentry into externally threaded-tubular parts ofl dierent sizes and having angular edges forinternal engagement with the tubularpart', screwl meanscarried by one of said jaws for engagement endwise'with the adjacent surface of the other jaw to separate said other jaw from said one jaw and thereby expand. said angular edges of said stepped down portionsinto bitingengagement withv the interior of said tubular part, and pin means carried by said one jaw and extending into openings'in said'other jaw to guide said other jaw in its movement away from and toward said one jaw and to limit separation of said other jaw from said one jaw.

References Citedin the le of this patent UNITED STATES PATENTS 195,186 Tyner Sept. 1l, 11877 1,501,889 j Mick July 15, 1924V 1,816,997 Brown Aug. 4, l93l 2,251,730 Caldwell Aug. 5, 194i FOREIGN PATENTS t 'j 118,578l sweden Apr. 8, 1947 594,111 Great Britain Nov. 3, 1947

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