US2097594A - Reversible ratchet wrench - Google Patents

Description

Nov. 2, 1937. w. c. KRESS 2,0971594 REVERSIBLE RATCHET WRENCH Filed May 18, 1936 R X 16w ATTORNE Patented Nov. 2, 1937 UNITED STATES 2.097.594 7 REVERSIBLE RA'rcHETj WRENCH V a Willard C. Kres's, Kenmore, N. Y, assignor to J. H. Williams & Co.,-BufEalo, N. Y., a corporation of New York Application May 18,1936, SerialNo. 80,386 V Claims.

This invention relates to reversible ratchet wrenches, and although it may be embodied in both large and small wrenches it is nevertheless particularly suited for use in large ratchet 5 wrenches adaptable for use in heavy construction work.

Wrenches used in such work are subjected to severe strains and they must consequently be of very rugged construction. In ratchet type wrenches for use on heavy work it is essential, not only that the working parts be sufficiently strong to withstand such strains, but that the wrench be sufficienly small that it may be used for tightening nuts and bolts in restricted corners as well as in easily accessible places.

An important object of this invention is the provision of a ratchet wrench wherein the load, incident to the turning of a socket, is carried by two or more gear teeth instead of by a single tooth, the said load being imposed upon each of said teeth through a plurality of pawls in such a way that backlash is eliminated. Another object of the invention is to provide easily removablesockets, for engaging a nut or bolt, having integrally formed therewith a ratchet Wheel adapted to be engaged by the pawls as aforesaid, whereby, even if one or more teeth in a ratchet wheel on one socket should be broken under extreme conditions, the wrench is never- 30 theless immediately available for use with other sockets.

Other objects and advantages of my invention will be apparent from the following specifica tion and from the accompanying drawing, wherein:

Figure 1 is a plan view of my improved wrench with the cover plate removed and a portion broken away to clearly illustrate the arrangement 40 ratchet wheel.

' Fig. 2 is a central longitudinal cross-section on the line 2-2 of Fig. 1.

Fig. 3 is a side elevation of a removable socket.

Fig. 4 is a plan view of the cover plate.

The drawing shows only the ratchet end of the wrench, the handle being elongated and extended beyond the broken portion toward the right of each of Figs. 1 and 2, as may be well understood. The wrench may preferably comprise a flattened ratchet head ll] formed at one end of a steel bar, said head being of suflicient width and thickness to accommodate the several parts hereinafter referred to. A bore ll extends completely through the ratchet head I 0 at one end thereof to receive a'ratchet wheel l2 formed of the several pawls and their coaction with the integrally upon a rotatable element] [3, which element also has an integral nut-engaging socket l4 suitably shaped to engage and turn nuts and bolts. A pawl chamber I5 is located/in the ratchet head, adjacent the bore ll,'and carries "6 within it inner pawls l6 and I1, and two outer pawls l8, all of which are adaptedto engagejthe teeth of the-ratchet wheel I Z to rotate the socket l4.

invention I have utilized pawls of the clapper type which are preferred in wrenches intended for use in construction work. It is important that pawls invariably work freely and become seated j properly within the teeth of the ratchet wheel, "and where, as in construction work, a certain amount of grit, mud, etc.,'is encountered, which may find its Way into-the mechanism, clapper type pawls are little affected by such adverse conditions for the reason that they contact the body of the Wrench over a relatively small area and as a result there is a minimum of friction which might tend to impair the free functioning of the pawls. While other types of pawls may be utilized within my invention they are less desirable for the reason that they engage-"the. Wrench body over a larger area and, consequently, are more likely to stick and fail to function under 7 conditions encountered in actual practice;

The pawls are arranged in sets, the inner'pawl'ilo l6 and one of the outer pawls l8 being'adapted to work on one side of the ratchet wheel, and the inner pawl l1 and the other outer pawl l8 being adapted to work upon the other side of the ratchet wheel. The pawls l6 and 'l! work about a common pivotal point at the center of the wrench, the pivot end .of pawl l6 being bifurcated to provide jaws Ilia within which is disposed a tongue Ila. of the pawl H. The jaws Ilia and the tongue Ila areboth substantially circular in cross-sec- 40 tion and of similar diameters, whereby theymay seat Within a centrally located bore l9 which extends partly through the ratchet head and communicates with the pawl chamber l5 at the latters most remote point from the ratchet wheel.

The pawls I8 are pivoted similarly Withinsimilar bores 20 communicating with the pawl cham'-' ber on each side of the Wrench, the pivoted ends of these pawls likewise bein'g subst antially circular in cross-section to permit them to 'work Within said bores. I The pawls I6 and I! are similar except with regard to their pivoted ends, which have already been described. They are adapted at their free ends to engage theiratchet wheel onopposite sides,

In the embodiment employed to illustrate this 10 whereby each is adapted to turn the socket M in an opposite direction. The pawls l8 are arranged to function similarly to the pawls 16, I1, and to engage teeth on the ratchet wheel which are adjacent to the teeth engaged by said latter pawls.

Means are provided for compressing and holding the several pawls into engagement with the ratchet wheel. These means are similar on each side of the wrench and may comprise a helical compression spring 33, one end of each of which is disposed within a seat Na. in the outer side of a pawl 18, and the other end of which presses against the side wall of the pawl chamber IS. The inner pawls l6 and I1 are somewhat broadened at their free ends, as at I62) and Nb, to afford means by which the said pawls-and the outer pawls l8 may be suitably spaced apart and by which the pressure of the helical springs 33 may be transmitted through the pawls l8 to the pawls l6 and I1, whereby both pawls on each side of the wrench may work together and in a proper relationship. The portions at 16b and Ill) are rounded, as shown, so that they may easily work upon the inner surfaces of the pawls 18.

Means are provided for selectively adjusting the mechanism so that the pawls on either or both sides of the ratchet wheel may be disengaged therefrom, this means, in the invention as disclosed herein, comprising a shifter plate 2! formed of a sheet of metal which is substantially semicircular in shape and may turn about a machine screw 22 which holds said plate and a cover plate 23 in place. Theshifter plate has a cam 24 fixed on the under side thereof to engage and urge outwardly, either or both the inner pawls l6, I1, and the coacting outer pawls I8. The shifter plate may be turned by a tongue 25 thereon which protrudes beyond the edge of the'cover plate and may be manually moved betwen an extreme position atone side of the wrench, as in Fig. 1, and a similar extreme position at the other side of the wrench, to selectively disengage the pawls in either side of the wrench. When the tongue 25 is disposed in a central position, all pawls are disengaged to permit the ratchet wheel 12 to be inserted into or removed'from the bore l I.

It will be seen from the drawing and from the foregoing description that the end surface of the free end of a pawl is in and moves in substantially the same plane as the plane of the tooth surface of the ratchet wheel which receives the compressive load transmitted through the pawl to effect rotation of said wheel. Thus the relative positioning of said-tooth surface and the pivot point of the pawl may remain substantially constant during the movement of the pawl between its initial engagement and its complete seating with respect to the said tooth surface of the ratchet wheel, the result beingthat there is no backlash inthe seating of such a single pawl with relation to the ratchet wheel.

Where, as in the present invention, it is desired to augment the strength of a wrench to enable it to handle heavy work, two or more pawls may be advantageously provided to simultaneous ly coact with a similar number of teeth on the ratchet wheel'to turn the latter in either direction, but it is obvious that to achieve, for each pawl, a coaction similar to that referred to in the preceding paragraph the pivotal points of the several pawls must be different with respect to the teeth at two or more peripheral points on said wheel.

Employing this principle in my present invention I have succeeded in gaining the advantage of the simultaneous functioning of two or more teeth of the ratchet wheel, while substantially eliminating backlash which is very objectionable in long wrenches adapted for use in construction work. The ratchet wheel 12 may easily be inserted into the bore ll, when the pawls are adjusted to a retracted or inoperative position, and has an annular ring 25, integrally formed therewith, which, when the ratchet wheel is completely seated within said bore, extends outside of the latter and is encircled by a collar 21 which rotatably seats upon the ratchet head l0 and within an annular groove 28 therein. Set screws 29 are threaded laterally through the ring 26 and seat within recesses 3E3 in the collar 21 to secure the rotatable member l3 against unintentional displacement of the latter from within the ratchet head. The collar 2'! is provided with an interiorly protruding portion 3! which fits within a groove 32 in the ring 26 and permits the said collar to be set into place inonly one position relatively to said ring and the set screws 29 and recesses 30 are so disposed that they register properly when the collar has been set into place. This arrangement greatly facilitates the assembling of the complete wrench for use.

The rotatable member I3 is open throughout it axial length so that the wrench may be used to turn nuts upon any length of bolt.

It will be understood that, although I have only described and illustrated one embodiment of my invention, it may nevertheless be used in numerous ways and with many modifications Without departing from the spirit of the invention as defined in the following claims.

What I claim is:

1. A. reversible ratchet wrench comprising a body, arotatable ratchet wheel having a single set of teeth, and a plurality of single-arm pawls disposed at opposite sides of a central longitudinal axis of the wrench, each of said pawls being pivoted at one end thereof on said body and having a ratchet-wheel engaging portion at the.other end thereof, said pawls, further, being disposed to work in a common plane whereby to coact with the single set of teeth of the ratchet wheel, a plurality of said pawls on each of said opposite sides of said axis being pivoted at separate pivot points and being adapted to simultaneously coact similarly with separate teeth on the ratchet wheel, the pawls on opposite sides of said axis being adapted to selectively coact oppositely with the ratchet wheel whereby to permit selective turning of the ratchet wheel, with the body, in either of opposite directions.

2. A ratchet wrench comprising a body portion. a ratchet wheel mounted thereon, a plurality of coacting pawls pivoted on said body portion and adapted to move, substantially in unison, into engagement with the ratchet wheel, a spring coacting with the outer side of one of said pawls and the latter coacting with another of said pawls whereby a plurality of pawls receive the tension of the said spring andare thereby urged into a position where they may engage said ratchet wheel.

3. A ratchet wrench comprising a body portion, a ratchet wheel mounted thereon, a springpressed outer pawl and an inner pawl in engagement with and coacting with said outer pawl, both said pawls being pivoted on said body portion and being adapted to move, substantially in unison into engagement with the ratchet wheel, and manually operable means engaging said inner pawl'for actuating both pawls to move them to a disengaged position relatively to the ratchet wheel.

4. A reversible ratchet wrench comprising a body portion, a ratchet Wheel mounted thereon, two clapper type outer pawls pivoted at points at each side of a central longitudinal axis of the wrench, two independently operable clapper type inner pawls pivoted at a common point on such axis, one outer and one inner pawl at each side of said axis being adapted to simultaneously and similarly coact with the ratchet wheel and to move in substantial unison into and out of operative engagement therewith, spring means adapted to urge each outer pawl and the coacting.

inner pawls into positions wherein they may engage said wheel, and centrally located means for manually actuating said inner pawls to move them and the outer pawls to positions wherein they may be out of engagement with said wheel.

5. A reversible ratchet wrench comprising a body portion, a ratchet wheel mounted thereon, two clapper type outer pawls pivoted at points at each side of a central longitudinal axis of the wrench, two clapper type inner pawls pivoted inwardly of the pivot points of said outer pawls,

an outer and an inner pawl at each side of said 7 axis coacting to permit them to be moved in substantial unison into and out of an engaged position relatively to the ratchet wheel, spring means WILLARD o. VKRESS.

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