US 1854513 A
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Description (OCR text may contain errors)
APM 19, i932. 1 A. HUMMEL 4 n REVERSIBLE RA'.I'C'HF'I'` WRENCH Filed March 29, 1950 l INVENToR.
sil- LuzsAJY u me! 7 ATTORNK Patented Apr. 19, 1932 UNITED sTATEs -PATENT OFFICEI LOUIS A. HUMMEL, F MILWAUKEE, WISCONSIN, ASSIGNOR, BY MESNE ASSIGNMENTS, TO SNAP-ON TOOLS, INC., 0F KENOSHA, WISCONSIN, A CORPORATION 0F DELAWARE REVERSIBLE RATCHET WRENCH Application led March 29, 1930. Serial N0. 439,873.
This invention relates to ratchet devices and more particularly to reversible ratchets for wrenches, although certain features thereof may be employed with equal advan tige for other purposes.
It contemplates more especially the provision of an improved ratchet device capable of instantaneous adjustment to enable reversal without withdrawal or change in position of its application for nut turning or other purposes.
With known ratcheting devices, it is necessary to withdraw the wrench or lever from registry with the nut to permit the reversed application thereof so that turning in an opposite direction may be effected. Then too, several sets of pawls have been resorted to in effecting reversal by independent adjusted engagement; however, such expedients in their known form have not proven entirely satisfactory owing to the intricate construction thereof which is not conducive vto dependable and rapid operation.
This invention contemplates a` function substantially similarto that; performed by the invention described in the assignees copending application serially numbered 423,- 7 96 and filed January 27, 1930; however, the structure is greatly simplified and the oper- A ation rendered more dependable for 'conven-.
ient manipulation. This is an important factor in ratchet wrenches owing to the fact i that they are employed in restricted locations where their manipulation is diicult and v adjustments found inconvenient. The primary variants from the copending structure` consist in a far lessexpensive device which is an important commercial consideration v from the standpoint of production costs, although the-operation is improved to the eX- tent of imparting greater dependability over a long period of time without necessary replacements.
One object f the present invention is to simplify the construction and improve the operation of devices of the character mentioned.
Another object is to provide an inexpensive ratchet which is readily reversible and 5 dependable in operation.
. trative embodiment of the present invention.
Still another object is to provide a ratchet having a unitary adjustment for effecting reversal without withdrawing the device from turning registry.
A further object is the provision of a ratchet having a unitary exteriorly accessible adjustment to control the ratcheting direct1on.
A still further object is the provision of a rotary pawl capable of engagement with a ratchet in different positions to effect ratcheting reversal.
Still a further object is to provide novel spring means of inexpensive construction for maintaining the ratchet device in predetermined adjustment for selective directional operation.
Other objects and advantages will appear from the following description of an illus- In the drawings:
Figure 1 is a view in lelevation of a device embodying features of the present invention, parts thereof being broken away to clarify .the showing.
Figure 2 is a fragmentary side'view'in elevation of the device shown in Figure 1, it being shown in partial section taken substan- Ytially along line II--II of Figure 1.
Y Figure 3 is a fragmentary view of the 8'0 wrench head with the pawl in a position opposite to that shown in Figure 1 Figure 4 is a view similar to Figure 3 with the pawl shown in its neutral position.
Figure 5 is a side view in elevation of the spring employed as a means of maintaining the pawl inl adjusted position. v Figure 6 vis a front view in elevation of the spring shown in Figure-5.
Figure 7 is a perspectiveview of the pawl shown in Figures 1 to 4. 1
The structure selected for illustration comprises a body 10 which is suitably recessed to define a circular chamber 11A for the reception of a revoluble member 12. The member 95 12 is retained within the recess 11 of the body 10 by means of a face plate 13 which con'` forms in contour therewith for attachment by j means of suitable fasteners 14, in this instance four. The confronting external 'surfaces of 100.
aligned bores 16 in communication with the -interior thereof, thereby rota-tively receiving the corresponding shaped hubs 17 of the revoluble member 12 journalled therein.
In order to impart rotation to the revoluble member 12 responsive to oscillatory movement of the body 10, the periphery thereof is provided with radially extending ratchet teeth 18 cut or otherwise formed for extension therefrom. As shown, a circular recess 19 is provided in the body 10 to communicate with the chamber 11, it being in longitudinal'alignment therewith to receive a correspondingly shaped pawl- 20 journalled for rotation therein with the periphery thereof partially disposed in the chamber-11. To this end, the pawl 20 has integral axial aligned hubs 21 received in correspondingly shaped bores 22 provided in the body 10 and closure j plate 13. A knob 22 having the stem 23 thereof pressed in a somewhat smaller aperture 24 provided axially within a pawl hub 21 to establish fixed connection therewith, constitutes a manual rotary adjustment for the pawl 20. To enable ratcheting of the revoluble member 12 in opposed directions by rotary adjustment of the knob 22,', the pawl 20 has the periphery thereof. interrupted to define oo nfronting pawl/ teeth 25 and 26. The pawl teeth 25 and 26 are complemental to the ratchet teeth 18 for independent meshing engagement therewith depending upon the rotary position of the pawl 20 which is adjusted by the knob 22 to control the directional rotation of the revoluble member or ratchet wheel 12. The pawl teeth 25 and 26 are suiiiciently spaced to enable the desired rotary throw of the head 10 for ratcheting purposes without interference withl the inactive pawl tooth, thereby partially rotating the pawl 20 about its axis responsive thereto -until the next successive ratchet tooth 18 is engaged.
To maintain the awl 20stationary and in adjusted positions or the desired directional ratcheting, a wire 27 o f spring steel or other suitably tempered material possessing an inherent spring is, in this instance, shaped to define orA simulate a question mark comprising a shank 28 with its circularly curved body 29 in continuity therewith. vAlthough the spring 27 may take anothei form, this partlcular shape serves very effectively lin that a transversely disposed extension 30 bent from the shank 28 may be pivotally anchored in an aperture 31 provided in the wrench body 10. In consequence thereof, the-spring 27 is pivotally confined betweenthe surface of the wrench head 10 and the cover plate 13 for oscillatory movement in a plane adjacent to the face of the pawl 20. As shown, the
circularly curved body 29 of the spring 27 terminates ina transversely disposed extension 32 in parallelism with the extension 30 and offset from the longitudinal median line thereof for resilient engagement with the cutout portion 33 defined by the interrupted periphery of the pawl 20 occasioned by the formation of the pawl teeth 25 and 26 thereon. f 1
With the -arrangement of parts above described, any suitable device for turning may be detachably or otherwise associated with therevoluble member 12. In the present embodiment a polygonal spindle 34 extends axially through and/or from the` revoluble member 12, it being preferably though not essentially provided with a spring impelled detent 35 of standard construction so that wrench sockets or other appliances may be detachably associated therewith. lThe manual pawl ladjusting knob 22 may be provided with suitable indicia 36, in this instance directional on7 and off indicators. Movement of the pawl 20 in a clockwise direction (viewed from Figure 1) will cause the pawl tooth 26 to engage the ratchet teeth 18 for rotating the revoluble member 12 in a correspending direction to tighten or turn on a right hand threaded member. Opposite pawl adjustment indicated by directional indicator off places the pawl tooth 25 in engagement with the ratchet teeth 18 to remove a correspondingly threaded member -or fastener, thereby enabling the ratchet to function in opposed directions with but a single and dupabl pawl easily adjusted for the purpose set ort This occurs in that the directional tooth for turning of the pawl 20, thereby requiring the rotationin unison of the wrench head 10 with the revoluble member 12, to impart a turning couple thereto for nut turning or vother purposes through the medium ofthe spindle 34 attached thereto for axial projection therefrom. l
With the return of the handle 37l which preferably though not essentially constitutes an integral extension of the wrench body 10, a forced reaction normal to surface (b) of either tooth 25 or 26, tends to impart rotary movement to the pawl 20 to the extent'that there is a partial rotary transfer thereof sufficient to remove the engaged tooth 25 or .2G-with the ratchet teeth 18 of the revoluble member 12, thereby momentarily allowing the pawl 20 to ride over the' ratchet teeth 18 until a successive engagement isfefl'ected responsive tothe association of the'handle37. For this purpose, the spring 27 yields to an extent suiiicient to permit the displacement of the pawl for temporary tooth disengagement until the succeeding ratchet tooth 18 `is engaged responsive to a change in the direction movement of thehandle 37 The particular succeeding ratchet tooth 18 which is engaged by the tooth or 26 of the pawl 20 varies with the extent to which the wrench handle 37 isl swung, and any angle of ratcheting may be resorted to for nut turning or other purposes, this being limited by the pitch of the ratchet teeth'18 which constitutes the smallest ratcheting angle.
It will thus be apparent that the spring 27 serves to impart an urge to the pawl 20 in one direction or the othei` depending upon the position of the latter. This is effected owing to the fact that the spring extension 32 bears against the surface (b) of the tooth 25 or 26 to maintainthe other tooth in engagement with the ratchet teeth 18. It will be observed that this takes place in that the spring '27 is displaceable laterally on` both sides of the longitudinal medianline along its point of pivotal anchor to the wrench body 10 owing to the lodgement of the eX- `tension 30 thereof in the aperture 31. In
short, the adjustment of the pawl 20 to transfer the ratchet engagement of the tooth 25 to the tooth 26 or v1ce versa shifts the point of contact between the spring extension 32 of the pawl 2O from one tooth to the other said ratchet-wheel, thereby transmitting the toothed reaction in diametral line with the curved body portions of said pawl, and a permanently curved wire spring pivotally anchored in said head portion for lodgement of the free end thereof between said teeth to maintain the adjusted position of said pawl.
2.v In a ratchet wrench, the combination with a wrench body havinga head portion,
a ratchet wheel journalled for rotary movement in said wrench head, there being a substantiallv circular recess in said wrench body for communication with said ratchet wheel, a pawl having diametral curved bearing outlines in a circumference conforming to said circular recess for conning rotation therein, an interrupted periphery on said pawl to define opposed teeth movable with -said pawl into and out of engagement with so that the disengaged pawl tooth serves as .i
a stop for the free extremity 27 which imparts an urge to the pawl 20 in the direction of the tooth engagement thereof. The spring 27 is, therefore, effective to maintain the pawl 20- in its adjusted lpositions, it being fer of the pawl 2() to its neutral position (Figure 4) coincident with the disengagement of both ratchet teeth 25 and 26 with the ratchet teeth 18 is thus held by the spring 27 in that the free extremity 32 thereof is disposed centrally within the cutout portion 33 to maintain this position.
Various changes may bevmade in the embodiment of the invention herein specifically described without departing from or sacriiicing any of the advantages of the invention as defined in the appended claims.
1. In a ratchet wrench, the combination with a wrench body having a head portion provided with communicating circular recesses, a toothed ratchet-wheel journalled in' one of said recesses, a pawl having diametrically disposed cylindrically curved body journalled for circular movement in the other recess, said pawl to form oppositely directed teeth engageable with said ratchet-wheel, means for circularly swinging said pawl about the curved portions thereof with oneor the other of said teeth into operative engagement with 32 of the spring worthy of note that the transan interrupted periphery on