US3724298A

US3724298A - Reversible ratchet-type wrench

Info

Publication number: US3724298A
Application number: US00137188A
Authority: US
Inventors: J Howard
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-04-26
Filing date: 1971-04-26
Publication date: 1973-04-03
Anticipated expiration: 1990-04-03

Abstract

A reversible ratchet-type wrench provided with a ratchet wheel and a pawl with two sets of teeth selectively engageable with the ratchet wheel. The pawl is also provided with two substantially flat surfaces which are on opposite sides of an angular projection that is located opposite the pivot which supports the pawl. The pawl is tilted on its pivot when the handle of the wrench is rotated through a predetermined relatively wide angle so that one of the two sets of teeth of the pawl engage the ratchet wheel depending upon the direction in which it is desired to turn the wrench. A spring-urged ball is supported by the handle in engagement with said angular projection of the pawl to provide a snap action in tilting the pawl after the handle is turned a certain amount whereby positive engagement of the selected set of teeth of the pawl with the ratchet wheel is obtained.

Description

United States Patent mi 11 3,724,298 Howard 1 Apr. 3, 1973 REVERSIBLE RATCH E'I -TYPE Primary Examiner-Robert Riordon WRENCH [76] Inventor: Joseph A. Howard, 22616 Summit Road, Los Gatos, Calif. 95030 [22] Filed: Apr. 26, 1971 {21] Appl. No.: 137,188

[52] US. Cl ..81/63 [51] Int. Cl. ..B25b 13/46 [58] Field of Search ..81/63, 63.1, 63.2, 62, 61; 145/74 [56] References Cited UNITED STATES PATENTS 754,012 3/1904 Reams ..81/63 1,926,103 9/1933 Kems ..81/63 2,686,446 8/1954 Livermont 81/63 UX 2,711,111 6/1955 Brame ..81/63 X 3,140,625 7/1964 Pannozzo ..81/63 Assistant Examiner-Roscoe V. Parker Attorney-Allen & Chromy [57] ABSTRACT A reversible ratchet-type wrench provided with a ratchet wheel'and a pawl with two sets of teeth selectively engageable with the ratchet wheel. The pawl is also provided with two substantially flat surfaces which are on opposite sides of an angular projection that is located opposite the pivot which supports the pawl. The pawl is tilted on its pivot when the handle of the wrench is rotated through a predetermined relatively wide angle so that one of the two sets of teeth of the'pawl engage the ratchet wheel depending upon the direction in which it is desired to turn the wrench. A spring-urged ball is supported by the handle in engagement with said angular projection of the pawl to provide a snap action in tilting the pawl after the handle is turned a certain amount whereby positive engagement of the selected set of teeth of the pawl with the ratchet wheel is obtained.

4 Claims, 8 Drawing Figures PATENTEBAPR3 I973 3,724,298

: 2| FIG.8

i; l2l6 2221 I9 JOSEPH A. HOWARD IO FIG] |8c 8 11421422 ATTORN S REVERSIBLE RATCHET-TYPE WRENCH DESCRIPTION OF THE INVENTION tively large angle, said pawl also being provided with an angular projection that is adapted to be engaged by a spring-urged ball supported by.the handle, said springurged ball providing a snap action to said pawl when said ball shifts from one side of the projection to the other after said pawl is rotated on its pivot by the turning of the handle so that the direction of the wrench may be reversed.

Other and further objects of this invention will be ap-- parent to those skilled in the art to which it relates fromthe following specification, claims and drawing.

lnaccordance with this invention there is provided an improved reversible ratchet-type wrench which may be reversed simply by turning the handle thereof through a predetermined angle. This angle is substantially greater than the small angular turning'of the handle that inadvertently takes place when the wrench is being used to tighten or loosen an object such as'a nut or bolt. This wrench is also provided with a snap action that comes into play when the direction of the wrench is being reversed. This snap action is provided by a spring-urged ball that is pressed against a triangular projection provided to the pawl which engages the ratchet wheel of the wrench. Thus when the pawl is being turned on its pivot by turning the handle the spring-urged ball traverses the inclined surfaces of the triangular projection and when it passes the apex thereof it provides the snap action which shifts the pawl on its pivot disengaging one set of teeth from the ratchet wheel and positively engaging the other set therewith. 1

Further details and features of this invention will be set forth in the following specification, claims and drawing, in which, briefly:

FIG. 1 is a side view of one embodiment of this reversible ratchet-type wrench;

FIG. 2 is a sectional view taken along the line 2-2 of FIG. 1;

FIG. 3 is an enlarged sectional view of the head of the wrench shown in FIG. 1 and 2;

FIG. 4 is a side view of another embodiment of this reversible ratchet-type wrench;

FIG. 5 is a view taken along the line 5-5 of FIG. 4 partially exploded;

FIG. 6 is a sectional view taken along the line 6-6 of FIG. 1 of a portion of the head of the wrench showing how the ratchet wheel is assembled therewith;

FIG. 7 is a sectional view taken along the line 7-7 of FIG. 5; and

FIG. 8 is a sectional view along the line 88 of FIG.

Referring to the drawing in detail, reference numeral 10 designates the head of the wrench which is provided with a cavity for receiving the ratchet wheel 11 and the pawl 12. The ratchet wheel 11 is provided with a square work-engaging member 11a which is pressed into the ratchet wheel. The member 11a is provided with a shoulder 1112 that engages the head 10 and forms one bearing for the wheel. The member 11c which is in the form of a thick washer is pressed on the end portion 1 1d and engages the head 10 to form the other bearing for member 11a. The ratchet wheel 11 is assembled with the head 10 and the member 11a is pressed into member 11b, wheel 11 and member lie to hold these. parts assembled with the head.

The pawl 12 is supported in the head 10 by a pivot pin 13 which extends therethrough and into holes formed in both sides of the head. Two sets of

teetch

14 and 15 are provided to opposite end portions of the pawl 12 and these sets of teeth are adapted to engage the teeth of the ratchet wheel 11 selectively. The triangular projection 16 is provided to the pawl 12 opposite the pivot pin 13. The head 10 is provided with a hole for receiving the end portion 17 of the handle 18. Fortion 17 is provided with a groove 19 which is adapted to engage the pin 20 to hold the handle portion 17 assembled with the head 10. v

' A cam 21 is formed on the inner end of the portion 17 and this cam is adapted to engageone or the other of the substantially

flat surfaces

22 and 23 of the pawl 12. Pins 10a are provided in the head 10 as shown in FIG. 8 to engage ,the cam 21 and limit the rotation thereof to less than one revolution. Thus when the handle 18 is rotated on its axis the pawl 12 is turned on its pivot 13 and one or the other of the two sets of teeth 14-15 is brought into engagement with the ratchet wheel 11 so that the wrench may be used to turn the work engaging member either clockwise or counterclockwise. When the pawl 12 is turned on its pivot one of the inclined surfaces of the projection 16 is traversed by the spring-urged ball 24 and when the ball 24 crosses the apex of this projection the pawl is subjected to a snap action so that the selected teeth thereof firmly engage the ratchet wheel.

Another embodiment of this invention is shown in FIGS. 4 and 5 and the parts of this embodiment which are the same or similar to the parts of the embodiments shown in FIGS. 1, 2 and 3 are designated by the same reference numerals. In the embodiment shown in FIGS. 4 and 5 the handle of the wrench is made in two

parts

18a and 18b. The part 18a is hollow and is rotatably supported on the inner part 18b which is provided with an end portion 18!: that is pressed into the head. The tubular handle member 18a is rotatably supported on the inner member 18b and a screw 18d is provided threaded into the outer end of the inner member 18b to hold the outer handle member assembled on member 18b. Shoulders 18e are provided on the end of the member 18b and a pin 18f is attached to the member 18a to engage the shoulders 18e and limit the rotation of member 18 a on the inner member 18b.

The head 10 of the embodiment shown in FIGS. 5 and 7' is provided with recesses for receiving the

pins

30 and 31 which cooperate with the cam 21a that is provided to the tubular handlemember 18a. Cam 21a engages the

pins

30 and 31 selectively and presses the pin 3 engaged against .the pawl 12. Thus when the cam 21a engages the pin 30 it causes this pin to engage the surface 22 of the pawl 12 and tilt this pawl on its pivot 13 so that the teeth 14 engage the ratchet wheel 11 so that the wrench may be used to turn the work-engaging member 11a in the clockwise direction. On the other hand, when the handle member 180 is turned about half a turn the cam 21a engages the pin 31 and causes this pin to engage the surface 23 of the pawl 12, the pawl is tilted on its pivot 13 and the teeth 15 thereof are brought into engagement with the ratchet wheel 11. At the same time the teeth 14 of the pawl are disengaged from the ratchet wheel so that the wrench is adjusted to turn the work-engaging member 11a in counterclockwise direction.

The embodiment shown in FIG. is also provided with a spring-urged ball 24 which is adapted to engage I the triangular projection 16 of the pawl 12 to produce the desired snap action when the pawl is being shifted on its pivot 13.

While I have shown and described a preferred form of the invention, it will be apparent that the invention can be varied and modified from the form shown so that the scope thereof should be limited only by the proper scope of the claims appended hereto.

Whatl claim is:

1. In a reversible ratchet-type wrench the combination of a head, a handle attached to said head, said handle being rotatable with respect to said head, a ratchet wheel mounted for rotation on the head, a pawl cooperating with said ratchet wheel, said pawl having two sets of teeth on .one side thereof, means selectively causing either of said sets of teeth to engage said ratchet wheel whereby said ratchet wheel may be turned in either direction selectively, said head having a cavity, pivot means supporting said pawl in said cavity, said pawl having an angular projection extending therefrom on the opposite side thereof, said angular projection having substantially flat surfaces onopposite sides thereof, said first mentioned means comprising means engaging said substantially flat surfaces selectively when-said handle is rotated with respect to said head, said last mentioned means rotating said pawl on said pivot means when said handle is rotated thereby selecting which of said two sets of teeth engage said ratchet wheel, spring-urged means supported by said handle engaging said angular projection to provide snap action in turning said pawl after turning of said pawl is started by turning of said handle.

2. In a reversible ratchet-type wrench, the combination as set forth in claim 1, further characterized in that said handle comprises a sleeve, a rod fixedly attached to said head, said sleeve being rotatable on said rod, and said first mentioned means includes a cam attached to said sleeve.

3. In a reversible ratchet-type wrench, the combination as set forth in claim 1, further characterized in that said surface engaging means comprises a cam attached tosaid handle engaging said substantially flat surfaces selectively.

I said cam to-turn said pawl on the pivot thereof.

Claims

1. In a reversible ratchet-type wrench the combination of a head, a handle attached to said head, said handle being rotatable with respect to said head, a ratchet wheel mounted for rotation on the head, a pawl cooperating with said ratchet wheel, said pawl having two sets of teeth on one side thereof, means selectively causing either of said sets of teeth to engage said ratchet wheel whereby said ratchet wheel may be turned in either direction selectively, said head having a cavity, pivot means supporting said pawl in said cavity, said pawl having an angular projection extending therefrom on the opposite side thereof, said angular projection having substantially flat surfaces on opposite sides thereof, said first mentioned means comprising means engaging said substantially flat surfaces selectively when said handle is rotated with respect to said head, said last mentioned means rotating said pawl on said pivot means when said handle is rotated thereby selecting which of said two sets of teeth engage said ratchet wheel, spring-urged means supported by said handle engaging said angular projection to provide snap action in turning said pawl after turning of said pawl is started by turning of said handle.

3. In a reversible ratchet-type wrench, the combination as set forth in claim 1, further characterized in that said surface engaging means comprises a cam attached to said handle engaging said substantially flat surfaces selectively.

4. In a reversible ratchet-type wrench, the combination as set forth in claim 2, further characterized in that said surface engaging means comprises pins slidable in said head and positioned to be engaged selectively by said cam to turn said pawl on the pivot thereof.