US 2193984 A
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Description (OCR text may contain errors)
March 19, 1940- H. A. RHINEVAULT REVERSIBLE RATCHET WRENCH Filed April 16, 1937 Patented Mar. 19, 1940 REVERSIBLE RATCHET WRENCH Harry A. Rhinevault, Chicago, Ill., ass'ignor to Armstrong Bros. Tool 00., Chicago, 111., ,a corporation of Illinois Application April 16, 1937, Serial No. 137,154
7 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 selectively 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 efiiciency of reversible 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 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 unduly straining any part of the assembly.
A further object is to provide new and improved means readily operable to render either of said pawls inactive. I Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawing in 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 removed, 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 l-A of Fig. 3.
Fig. 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 describe in detail, the preferred embodiment, but it is to be understood that I do not thereby intend to limit the inventionvto the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit .nect the two recesses.
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 fiat elongated body Ill having a handle l l at one end. Preferably, the body It and the handle H are formed as a one-piece forging.
The body It is hollow for housing the operating mechanism. One face of the body is closed 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 R3 to receive a removable cover or closure plate M.
Internally the forward end of the body defines a substantially circular recess it to receive a ratchet wheel H having suitable ratchet teeth ill on its periphery. These teeth are uniformly spaced, and preferably are symmetrical and V- shaped in form with oppositely disposed faces 49 and ill! of identical pitch.
Projecting axially from one side of the ratchet wheel through an opening 2| in the cover plate it is a trunnion 22. On its opposite side the wheel has an enlarged trunnion 23 which extends into an opening 2c in the base wall l2. It will be evident that the openings 2i and Z4 afiord a suite able bearing for the respective trunnions and that the cover plate It serves to hold the ratchet T OF'FlQE W Wheel in position within the recess 15. Driving :30
driving engagement with a suitable replaceable socket tool 25 (Fig. 1).
Rearwardly from the ratchet recess l5, the hollow head. It defines a second slightly, shallower recess 27. Between the recesses is a narrow transverse wall 23 which contacts the inside of the cover-plate. Formed in the wall 28 is a pair of identical passageways 2t and 36 which con- As shown, the passages are formed equidistant from the longitudinal center line of the head it. Each passage has an inner short bearing surface 34 formed at the end of the land portion of the wall 28. ln spaced parallel opposition to the short surface is a long outer bearing surface 32 which is formed on the interior'wall of the housing. This long bearing surface may be tangentially disposed with respect to diametrically opposite sides of the ratchet wheel ll (Figs. '2 and 3).
The passages 29 and 38! provide guideways for 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 as to be interchangeable. Each pawl has opposite parallel bearing faces and 36 slidably engageable with the bearing surfaces 3| and 32, respectively, of its guideway.
At its forward end each of the pawls is equipped with an inwardly facing, offset shoulder 31 adapted for engagement with a tooth I8 of the ratchet. The relationship of the shoulder 31 to the inner bearing face 35 of the pawl is such, moreover that both will simultaneously engage with adjacent teeth of the ratchet. As a result, the bearing face 35 and the shoulder 31 of the pawl 33 will engage with the faces I9 of the ratchet teeth as seen in Fig. 2 to hold the ratchet I! and the body 10 against relative movement except as indicated by the arrow. Engagement in similar manner between the bearing face 35 and the shoulder 31 of the pawl 34 and the faces 20 of the ratchet teeth will hold the ratchet wheel and the body against relative movement 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 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 great power is transmitted through the wrench.
To permit movement of the ratchet teeth I8 past the forward end of the active pawl without driving engagement during the idle or reverse stroke of the wrench in the selected direction, 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 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 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 4| in the peripheral wall of the chamber 21.
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 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 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 diameter mounted on the wall I2 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 21, with the upper end abutting the underside of an overlying offset portion 45 of the cover plate [4.
A screw bolt 41 is extended through the offset portion 45 and the sleeve 44 into threaded engagement with the base wall [2. Thus, the single screw 41 serves to hold the cover plate M as well as the sleeve 44 in position.
The periphery of the sleeve 44 projects into the path of reciprocation of the heel portion 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 position. 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 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 l1. At the same time, the heel 43 of the pawl 34 is in engagement 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 49 coacts with the forward face of the 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 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, 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.
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 5| in the cover plate and is received between 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 olfset portion 45 of the cover plate I 4. Thus, manual 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 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 standardized 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.
I claim as my invention:
1. In combination in a ratchet wrench of the character described, a body having a rotatable toothed ratchet, a reciprocable pawl having resilient means for urging the same into engagement at one end with the teeth of said ratchet to hold the latter against rotation relative to said body in one direction, the opposite end of said pawl having a laterally projecting heel portion, a hollow cylindrical member, an element extending into said member to maintain the latter in 76 position for rotation upon a fixed axis adjacent to said pawl and with its periphery located for engagement in one rotary position with said heel portion to hold said pawl away from said ratchet, said member having a recess therein for receiving said heel portion in another relative rotary position thereof to permit movement of the pawl into engagement with said ratchet, and means held in position by said element for rotating said member to force a side defining said recess rearwardly against said heel to retract the pawl.
2. In combination in a reversible ratchet wrench of the character described a recessed body having a reversibly rotatable ,toothed ratchet wheel mounted therein, mechanism including a pair of separately movable pawls arranged to coact with said ratchet wheel to hold the same respectively against rotation in opposite directions relative to said body, a hollow cylindrical selector adapted for relatively shifting said pawls to release said ratchet alternately for movement in said opposite directions, a plate coactive with said body for enclosing said ratchet and said pawls, and a securing element for fastening said plate in position and serving as an axle for said selector.
3. In combination in a reversible ratchet wrench of the character described, a. hollow body ,having a toothed ratchet reversibly movable the same, removable closure means closing said.
body, and a single screw for securing said closure means in place and for maintaining said element and said actuating means in operative relation.
4. In combination in a reversible ratchet wrench of the character described, a body having a recess opening toward one side thereof, a toothed rotatable ratchet within said recess, mechanism coactive with said ratchet selectively operable for alternately releasing said ratchet for rotation in opposite directions, an elongated pivotal member forming part of said reversing mechanism projecting from said recess, a closure plate coacting with said one side of said body and having an offset portion to receive said member, said plate having a slot opening rearwardly from said offset portion, and actuating means extending from said member and projecting through said slot for pivoting said member.
5. A reversible ratchet wrench comprising, in combination, a body including a head having a recess, a toothed ratchet wheel mounted in said recess, a pair of pawls mounted for longitudinal reciprocation relative to the teeth of said wheel, a tubular selector member coacting with said pawls and projecting from said recess, a plate having an offset portion to receive the projecting portion of said selector member and coacting with said head to close said recess, means for actuating said selector member projecting therefrom through said plate, and an attachment screw passing through said offset portion and said selector member to maintain the same in assembled relation.
6. .In combination in a reversible ratchet wrench, a body having a recess, a toothed ratchet wheel mounted within said recess, a pair of pawls located to control rotary movement of said ratchet wheel in opposite directions, heels upon said pawls, means for actuating said pawls including a sleeve-like selector member having a longitudinal slot and adapted in, one position relative to said pawls to engage the heel of one of said pawls to hold such pawl away from said ratchet wheel while permitting the heel of the other pawl to enter said slot so that the latter pawl may move into engagement with said ratchet wheel, and in another position to reverse the relation of said pawls to said ratchet wheel, a plate for closing said recess, and a securing element passing through said plate and through said selector member to maintain the latter in operative position relative to said pawls.
7. In combination in a reversible ratchet wrench, a body, a toothed ratchet wheel sup- HARRY A. RHINEVAULT.