Reversible ratchet wrench

March 19, 1940. h. a. rhinevault 2,193,984

REVERSIBLE RATCHET WRENCH Filed April 16, 1937

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Patented Mar. 19, 1940

2,193,984

UNITED STATES PATENT OFFICE

2,193,984

REVERSIBLE RATCHET WRENCH

Harry A. Rhinevault, Chicago, III., assignor to Armstrong Bros. Tool Co., Chicago, Ill., .a corporation of Illinois

Application April 16, 1937, Serial No. 137,154

Claims. (Cl. 192—43.2)

This invention relates to improvements in reversible ratchet wrenches adapted for loosening or tightening nuts or bolts, and more particularly concerns wrenches of this type having a selec5 tively reversible action enabling the transmission of force to the work in opposite directions without shifting of the work-engaging position.

One object of the present invention is to improve the construction and efficiency of reversible 10 ratchet wrenches by the provision of a novel ratchet reversing mechanism.

Another object is to improve the ratchet reversing mechanism for wrenches of this type, whereby to increase the ease with which reversal 15 may be effected, to avoid objectionable wear and thereby the possibility of slipping or impairment of power, and to distribute the strains in use uniformly throughout the coacting parts of the wrench.

More specifically stated, an object of the invention resides in the provision of a ratchet wrench having a pair of oppositely acting plunger type pawls which are adapted to be rendered selectively operable, and which are constructed to present exceptionally large contact areas both to the body of the tool and to the ratchet so as to enable effectual transmission of great force without tmduly straining any part of the assembly.

A further Object is to provide new and im30 proved means readily operable to render either of said pawls inactive.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawing in 35 which:

Figure 1 is a perspective view of a wrench embodying the features of the invention.

Figs. 2 and 3 are two enlarged fragmentary plan views of, the wrench with the top cover re40 moved, and illustrating the ratchet drive mechanism respectively adapted for operation in reverse directions.

Fig. 4 is a longitudinal sectional view taken substantially along the line 4—4 of Fig. 3.

pig. 5 is an enlarged perspective view of various detailed parts of the mechanism.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawing and will herein. ⁵⁰ describe in detail, the preferred embodiment, but it is to be understood that I do not thereby intend to limit the invention, to the specific form disclosed, but intend to cover all modifications and __ alternative constructions falling within the spirit 55 and scope of the invention as expressed in the appended claims.

Referring more particularly to the drawing, the invention is illustrated as embodied in a ratchet wrench comprising a flat elongated body ί 0 hav- 5 ing a handle !I at one end. Preferably, the body IQ and the handle II are formed as a one-piece forging.

The body 18 is hollow for .housing the operating mechanism. One face of the body is closed 10 and serves as a base wall 12 and the opposite face of the body is open. Within the inner edge of the later face is formed a shoulder 13 to receive a removable cover or closure plate 14.

Internally the forward end of the body defines 15 a substantially circular recess 15 to receive a ratchet wheel 11 having suitable ratchet teeth 18 on its periphery. These teeth are uniformly spaced, and preferably ars symmetrical and Vshaped in form with oppositely disposed faces 19 20 and 20 of identical pitch.

Projecting axially from one side of the ratchet wheel through an opening 21 in the cover plate 14. is a trunnion 22. On its opposite side the wheel has an enlarged trunnion 23 which extends 25 into an opening 24 in the base wall 12. It will be evident that the openings 21 and 24 afford a suitable bearing for the respective trunnions and that the cover plate 14 serves to hold the ratchet wheel in position within the recess 15. Driving ,30 means of suitable form adapted for releasable engagement with a bolt or nut to be driven or loosened is associated with the ratchet wheel 17. In the present instance, this means is shown in the form of a square stud or plug 25' adapted for 35 driving engagement with a suitable replaceable socket tool 25 (Fig. 1).

Rearwardly from the ratchet recess 15, the hollow head 19 defines a second slightly, shallower recess 27. Between the, recesses is a narrow ₄₀transverse wall 23 which contacts the inside of the cover plate. Formed in the wall 28 is a pair of identical passageways 29 and 30 which connect the two recesses. As shown, the passages are formed equidistant from the longitudinal 45 center line of the head 10. Each passage has an inner short bearing surface 31 formed at the end of the land portion of the wall 28, In spaced parallel opposition to the short surface is a long outer bearing surface 32 which is formed on the 55 interior wall of the housing. This long bearing surface may be tangentially disposed with respect to diametrically opposite sides of the ratchet wheel 17 (Figs. 2 and 3).

The passages 29 and 38 provide guideways for ₅₅

2,193,984 alternately active ratchet holding means such as reciprocable pawls 33 and 34. Both pawls may be of generally elongated flattened form, and they are preferably identical as to shape so 5 as to be interchangeable. Each pawl has opposite parallel bearing faces 35 and 36 slidably engageable with the bearing surfaces 3f and 32, respectively, of its guideway.

At its forward end each of the pawls is ₁₀ equipped with an inwardly facing, offset shoulder 37 adapted for engagement with a tooth 18 of the ratchet. The relationship of the shoulder 37 to the inner bearing face 35 of the pawl is such, moreover that both will simultaneously en15 gage with adjacent teeth of the ratchet. As a result, the bearing face 35 and the shoulder 37 of the pawl 33 will engage with the faces 19 of the ratchet teeth as seen in Fig. 2 to hold the ratchet 17 and the body 10 against relative move20 ment except as indicated by the arrow. Engagement in similar manner between the bearing face 35 and the shoulder 37 of the pawl 34 and the faces 20 of the ratchet teeth will hold the ratchet wheel and the body against relative movement 25 except as shown by the arrow in Fig. 3. In either event a heavy force may be applied effectively by the pawls against the ratchet teeth to rotate the nut or bolt selectively in either direction. The large aggregate contacting areas between the 30 ratchet teeth and the pawls, and the substantial backing afforded by the outer surfaces 32 of the guideways 29, 30 coacting with the faces 36 of the pawls, avoid undue wear and unequal strain upon any of the coacting parts even though 35 great power is transmitted through the wrench.

To permit movement of the ratchet teeth 18 past the forward end of the active pawl without driving engagement during the idle or reverse stroke of the wrench in the selected direction, 40 each pawl is provided at its forward end with a transverse abutment face 38 adapted to be acted on by the teeth with a force directed generally longitudinally of the guideways 29, 30. This face 38 may be biased slightly in the direction of the 45 cam action of the teeth 18 thereon.

Coactive with each of the pawls for urging the same into engagement with the ratchet is a yieldable means of suitable character. As shown, helical compression springs 39 seat at their forward 50 ends within shallow axial recesses or sockets 40 (Fig. 2) in the rear ends of the respective pawls and at their rearward ends within suitably located recesses 41 in the peripheral wall of the chamber 27.

In the use of the tool, either of the pawls 33 or 34 is allowed to engage the ratchet while the other pawl is retracted and held inactive by forcing the same rearwardly against its spring 39. For this purpose, each of the pawls is provided 00 in its inner longitudinal side with an elongated clearance recess 42 defining a laterally projecting heel portion 43 at the rear end. Adapted for selective engagement with the heel portions 43 of the pawls is a reversibly acting means operable 65 to retract and hold either pawl in its inoperative position while permitting the other pawl to move into operative engagement with the ratchet. Herein the selector means is shown as a cylindrical tumbler member or sleeve 44 of suitable di70 ameter mounted on the wall 12 for rotation between the opposed recesses 42.

The sleeve 44 may be of a length to project slightly beyond the open side of the chamber 27, with the upper end abutting the underside of an ₇5 overlying offset portion 45 of the cover plate 14.

A screw bolt 47 is extended through the offset portion 45 and the sleeve 44 into threaded engagement with the base wall 12. Thus, the single screw 47 serves to hold the cover plate 14 as well as the sleeve 44 in position. 5

The periphery of the sleeve 44 projects into the path of reciprocation of the heel portions 43 of the pawls, and is adapted in different positions of adjustment to engage the forward edges thereof to hold either of the pawls in the inactive po- io sition. To permit movement of either selected pawl into its operative position, the selector sleeve has a longitudinal recess, such as a slot, notch or groove 49 preferably with radially disposed sides to receive one or the other of the heel 15 portions 43. Thus, by reference to Fig. 2, it will be seen that when the heel 43 of the pawl 33 is within the groove 49 this pawl is in its operative relation to the ratchet wheel 17. At the same time, the heel 43 of the pawl 34 is in en- 20 gagement with the periphery of the selector sleeve 44, whereby the latter pawl is held in its inactive position. Upon rotation of the selector sleeve in a counterclockwise direction one side of the notch 4S coacts with the forward face of the 25 heel 43 of the pawl 33 to move this pawl rearwardly toward inactive position until ultimately the forward edge of the heel engages the periphery of the sleeve. Continued rotation of the selector sleeve 44 in this direction causes the 30 notch 49 thereof to receive the heel 43 of the pawl 34 thereby permitting forward movement of the latter into active position as shown in Fig. 3. It will be evident that when the selector sleeve 44 is rotated clockwise from the position of Fig. 3, 35 the foregoing action will be reversed to bring the parts into the relative positions of Fig. 2. As a result, the position of either pawl is determinable by the location of the groove 49 relative to the heel portion thereof. ₄₀

For convenient manual operation of the reversing mechanism, an arm or lever 50 is associated with the selector sleeve 44. As shown, the lever 50 projects through a rearwardly opening arcuate slot 51 in the cover plate and is received between 45 the sides of the groove 49 in the sleeve. On the inner end of the lever 50 is an annulus 52 which is seated in an annular recess 53 in the end of the sleeve 44 and is held in assembly by the offset portion 45 of the cover plate 14. Thus, man- _soual actuation of the lever in opposite directions will effect rotation of the sleeve correspondingly.

From the foregoing, it will be apparent that the present invention has a number of important advantages and refinements, among which may 55 be mentioned the simplified arrangement of parts ° wherein a single element serves as an axis about which operation of the reversing mechanism is centered and also as the securing means for all of the removable parts of the wrench; the stand- ₆₀ardized structure of the several parts which facilitates manufacture and assembly of the tool; and the sturdy construction and smooth, efficient operation of the novel reversing mechanism.