US2715955A - Reversible ratchet device for wrenches - Google Patents

Description

Aug. 23, 1955 A. P. STONE REVERSIBLE RATCHET DEVICE FOR WRENCHES Filed May 13, 1950 INVENTOR ARTHUR P. STONE ATTORNEY United States Patent REVERSIBLE PQXTCHET DEVICE FOR W'RENCHES Arthur P. Stone, Akron, fihio, assignor to The Wright Tool and Forge Company, Barberton, Ohio, a corporation of Ohio Application IVIay 13, 195% Serial No. 161,790

6 Ciairns.

tively large sizes due to having a large number of parts a and requiring substantial space for connectively mounting the pawls.

One object of the present invention is to provide an improved ratchet mechanism w ich makes possible the provision of a ratchet wrench of lightweight construction capable of withstanding relatively heavy loads as compared with prior art wrenches of similar sizes.

Another object of the invention is to provide a ratchet wrench of the character described which is of reiatively simple construction, having a minimum number of parts, and which may be economically manufactured by use of automatic machinery.

Another object of the invention is to provide a ratchet wrench mechanism of the character described, which is relatively easy to assemble in production, and similarly easy to take apart and reassemble as for cleaning or repairing purposes.

Another object of the invention is to provide a ratchet wrench of the character described, in which the reversing mechanism is positive in action and not subject to accidental reversal as by jarring in use.

These and other objects of the invention will be manifest from the following brief description and the accompanying rawings.

Of the accompanying drawings:

Figure l is a top plan view of a ratchet wrench embodying the features of the invention.

Figure 2 is a fragmentary cross-section, on an enlarged scale through the head portion of the wrench and taken substantially on the line 22 of Figure 1.

Figure 3 is a horizontal cross-section, on the same scale, taken substantially on the line 3-3 of Figure 2.

Figure 4 is a similar horizontal cross-section, but taken on the line 44 of Figure 2.

Figure 5 is a transverse cross-section on the same scale, taken substantially on the line 55 of Figure 3.

Figure 6 is an explosion view of the essential parts of the ratchet wrench mechanism shown in Figures 1 to 5.

Referring to the drawing generally, there is illustrated the ratchet wrench 1G, embodying the features of the invention for turning various sized wrench sockets of known type, one such wrench socket being indicated at 11 in chain-dotted lines in Figure 2. The Wrench includes a head portion 12, having an opening 13 therethrough between opposite flat sides 14 and 15 thereof, and having an integral handle 16 extending from the same at right angles to the axis of the opening. A reversible ratchet mechanism 17, on which the socket 11 is relatively nonrotatably attachable, is mounted in said opening 13 to be turned with the head in reverse directions of operation of the same for turning the socket in a manner to be described later.

The reversing ratchet mechanism 17 may include a shank member 18 received within the opening 13 of the head 12, and having an annular retaining shoulder or flange 19 rotatably seated in a recessed annular seat 2i) in one fiat face of the head, the shank being retained on the head by means of a disc-like plate 22 rotatably seated in an annular recessed seat portion 22:: in the opposite face 14 of the head and secured to the shank by means of a pair of screws 23, 23 received through the shank and through inwardly extending spaced portions 24 and 25 thereof against the inner end of which the plate 22 is engaged. The shank portions or protuberances 24 and 25 are shown as being in the form of two segments of a cylinder defining a bifurcation of the shank having cylindrical surfaces 26 and 27 in spaced relation to the circumferentially spaced teeth 28 completely around the periphery of the opening 13. The portions 24 and 25 define a central space 29 within the opening 13 and communicating with said toothed periphery at substantially diametrically opposite sides of the opening, (see Figure 3). A pair of spaced oppositely disposed pawls 31 and 32 each have elongated round end portions pivotally received in transversely semi-circular sockets 33 and 34, in an inwardly presented face of the protuberance 24, and also have stern extensions 35 and 37 pivotally received in suitable bores in the shank outwardly of the juncture of the protuberance with the flanged part of the shank, the pawls being located at opposite sides of a cylindrical indexing stem 38 freely received through an aperture 41a in the plate 22 and extended freely through the space 29 between the protuberances to be rotatably received in a bore 39 in the outer part of shank 18. The inner face of the segment or protuberance 24 may be recessed at 46 for rotatable engagement of stem 38 therewith. A narrow space, however, is provided between stem 38 and the other protuberances 25 for free reception of an arcuate, relatively stiff spring-wire link 42, pivotally hooked at its opposite ends to the spaced pawls 31 and 32. The link 42, may be of non-flexible material or structure because it is desired to swing both pawls in either of opposite directions in unison, as will be described later.

A knob 43 of the stem 38, outwardly of the plate 22, facilitates rotation of the indexing stem 38 between two i stop positions determined by stop means to be described later. In one such position, a ball 44 of a spring-pressed detent 45 engages one of the pawls 31 to urge the same into engagement of a toothed outer end thereof with a series of complemental teeth 28 of the wrench head, while the other pawl 32 is maintained out of mesh with the teeth 28 by the spring link 42 (see Figure 3). Conversely in the other stop position of the stem the yielding detent ball 44 will urge the pawl 32 into meshing engagement with the teeth 28, and link 42 will at the same time urge pawl 31 out of engagement with said teeth. The teeth of the pawls are arranged so that in the respective positions of meshing engagement thereof with respect to the teeth 28, the shank is rotatable with the head 12 in one direction or the other. With rotation of the head in the opposite directions for each said position of the pawls, the same will be dragged over the teeth 28, thereby permitting rotation of the head 12 relative of the shank 18. An arcuate groove 45 is provided in the recess for a ready passage of the ball 44 and thereby to facilitate free rotative movement of stem 38 from one said stop position to the other.

The previously referred-to stop means for the indexing mechanism may constitute a pin 46 extended from a reduced cylindrical neck portion 47 in the stem 38, the pin being engageable at substantially diametricallyopposite points with arcuately spaced stop shoulders 43 and 49 (see Figure 4) provided by enlarging the opening 41a in the plate 22 through which the stem is rotatablyreceived.

' Neck portion 47 has rotational bearing engagement with the smaller semi-circular portion of opening 41, and the enlargement 41a thereof facilitates the assembly of the stern 38, shank 18, plate 22 and the associated parts thereof in the interlo cked-relationship best illustrated in Figures 2, 3 and .4, wherein the stem 38 is rotatably retained against axial movement with respect to the shank,

'by the plate 22 complementally engaging within the groove defined by the reduced neck portion. Said stop shoulders 48 and 49 are each located on radial lines from the center'of the stem, at angles to, each other slightly .greater than 180 degrees, so that in either said stop position of pin 46 against said shoulders the ball, while having urged the respective pawl into meshing engagement with the teeth 28, will be stopped against an inclined inner fiat face 31a of the pawl, as best shown in Figure 3 said inclined face thereby serving as a yieldingly releasable stop means for preventing accidental reverse rotation of the 2 for tightening the nut, the indexing knob 43' is set toen- 'gage the pin 46-with stop shoulders 49, in which con'di-' tion the pawl'31 is urged into meshing engagement with the teeth 28 on head 12, against the yielding pressure of the spring-pressed ball 44 as best shown in Figures 2, 3,

V '4 and 5, the pawl 31 being yieldingly retained in this relative position'as described above, and pawl 32 being held out of engagement with the teeth 28 by the springlink 42. The nut may then be tightened by alternately turning the wrench head by means of handle 10 in opposite directions, the clockwise rotation thereby through engagement of pawl 31 with the teeth 28 being efiective to turn the" shank 18, socket 11 and the nut (not shown),

' [and reverse or counter-clockwise rotation of the head merely drags the pawl 31 over the teeth 28 to advance the pawl for reengagernent'of the same with the teeth for further clockwise rotation of the shank.

7 Conversely the tool is set for loosening a nut by turning the knob 43 in a counter-clockwise direction relatively of the shank 18 as viewed in Figures 1, 3 and 4, against the action of the spring-pressed ball 44, until the pin 46 engages'stop shoulder 48andthe ball44 engages the inner face 32a of pawl 32 in an inclined'position of the same, as described above, in which pawl 32 is yieldingly held in meshing engagement with the'teeth 28. In this engaged position of pawl 32, the pawl 31 is maintained out of engagement with teeth 28 by the link 42: Operation of the tool is otherwise the same as before except that the pawl 32 drives the shank 18 in counter-clockwise direction.

It will be seen particularly from Figure 6 that the improved wrench includes relatively few parts, which for 1 the most part may be economically produced by use of "automatic machinery. The wrench, moreover, may be quickly assembled or taken apart for production, or repair, or other purposes. The arcuate link' 42 among 7 other things makes possible provision of a compact tool which is relatively powerful as compared with similar tools of the same weight and size;

Modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims. 7

What is claimedis:

1. A' reversible ratchet device of the character de-t scribed comprising a headthavingan openingjtherein, a

member relatively rotatably mounted on said head to, be

teeth on the inner periphery thereof, separate laterally oppositely disposed pawls pivotally mounted on said part for driving engagement with said spaced teeth in opposite directions of relative rotation of the member in said head, a link pivotally connected at opposite ends thereof to the respective said pawls to extend unobstructedly between the same and to be freely movable laterally, whereby through said link said pawls are swingable in unison in either 'direction laterally, an element mountedin said member to be rotatable about said axis, and indexing means operable upon relative rotation of the element in either of opposite directions with respect to said rotatable member and in cluding a portion carried by said element engageable with a corresponding said pawl to urge the same outwardly into driving engagement with said teeth while said con necting link correspondingly urges the other pawl inwardly out of driving engagement with the teeth.

2. A reversible ratchet device of the character described comprising a head having an opening therein,

a member relatively rotatably mounted on said head to be rotatable about an axis and having a part received in said opening, said opening having circumferentially spaced teeth on the inner periphery thereof separate laterally oppositely disposed pawls pivotally mounted on said part for driving engagementfwith said spaced teeth in opposite directions of relative rotation 'of, the

.member in said head, a link pivotally connected at opposite ends thereof to the respective said pawls to eX-' tend unobstructedly between the same and to be freely movable laterally, whereby said pawls are swingable in unison in either direction, an element shiftably mounted in said member to be rotatable about said pressed detent engageable with a corresponding said pawl to urge the same outwardly into driving engagement with said teeth while said' connecting link urges the other pawl inwardly out of driving engagement with the teeth, said head having annular seats' on opposite I sides thereof, said member including separable parts having annular parts relatively rotatably seating in said seats, and means being provided for securing said separable portions together.

3. A reversible ratchet device of the character de-,

scribed comprising a head having an opening therethrough and peripheral seat portions at opposite sides of said head, a member including a shank received within said opening and having an annular retaining shoulder rotatably' engaging one said seat, and a retaining element, secured to said shank and 'rotatably engaging the other said seat for retaining the member against axial movement on the head, said opening having circumferentially spaced teeth on the periphery thereof, said shank having thereon spaced axially ine wardly extending portions defining a central space within said opening and communicating with said toothed periphery at substantially diametrically opposed portions thereof, separate oppositely disposed pawls pivotally mounted on said shank to extend within said central space at laterally opposite sides of the axis of rotation of said member for selective driving engagement with said spaced teeth in opposite directions of rotation of said shank relatively of said head, a link pivotally connected at opposite ends to the respective ber to extend iHtOt said central space between said pawls, said'stem having an outward protuberance there--.

on manually operable to turn the same with respect to said member, and spring-pressed detentmeans on said stem engageable with one or other of said pawls upon manual rotation of the stem relatively of said member for urging said one pawl outwardly into driving engagement with said teeth while said link urges the other pawl inwardly out of engagement with the teeth.

4. A ratchet device as set forth in claim 3, said element being a plate, means being provided for releasably securing said plate to said inwardly extending shank portions, said plate having a recess through which said stem is received, said recess being at least partially enlarged to define arcuately spaced stop shoulders, said stem having a projection therefrom engageable with said shoulders in stop positions in their respective toothengaging positions of said pawls.

5. A ratchet device as set forth in claim 3, said link being of relatively stifli elongated material arched around said stem within said central space in an area thereof between the stem and adjacent said inwardly extending portion.

6. A ratchet device as set forth in claim 3, said element being a plate, means being provided for releasably securing said plate to said inwardly extending shank portions, said plate having a recess through which said stem is received, said recess being at least partially enlarged to define arcuately spaced stop shoulders, said stem having a projection therefrom engageable with one or other of said shoulders in opposite stop positions corresponding to the respective opposite toothengaging positions of said pawls, said detent means being a spring-pressed ball projecting from said stem, the pivotal points of said pawls being at opposite sides of said stem, one of said inwardly extending portions of the shank having an arcuate track yieldingly retaining said ball inwardly retracted in said stem in all positions of rotation between said stop opposite positions of said stem.

References Cited in the file of this patent UNITED STATES PATENTS 192,018 Rose June 12, 1877 801,954 Wood Oct. 17, 1905 1,424,045 Sprague July 25, 1922 2,020,883 Gagne Nov. 12, 1935 2,154,649 Wishinsky Apr. 18, 1939 2,188,846 Rueb Jan. 30, 1940 2,202,402 Rueb May 28, 1940 2,407,558 Kress Sept. 10, 1946 2,507,889 Cofling May 16, 1950 2,508,568 Ellison May 23, 1950 2,620,051 Kaplan Dec. 2, 1952

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