US3290969A

US3290969A - Reversible ratchet wrench having linear sliding manually actuated pawls

Info

Publication number: US3290969A
Application number: US353493A
Authority: US
Inventors: Clifford A Bergquist; John A Over
Original assignee: PENDLETON TOOL IND Inc
Current assignee: PENDLETON TOOL IND Inc
Priority date: 1964-03-20
Filing date: 1964-03-20
Publication date: 1966-12-13
Anticipated expiration: 1983-12-13
Also published as: GB1088087A

Description

1966 c. A. BERGQUIST ETAL REVERSIBLE RATCHET WRENCH HAVING LINEAR SLIDING MANUALLY ACTUATED PAWIJS Filed March 20, 1964 @IFFOIQD A. Baa E0019; Johw A. @VE

INVENTOR-S.

United States Patent 3,290,969 REVERSIBLE RATCHET WRENCH HAVING LINEAR SLIDING MANUALLY ACTUATED PAWLS Clifiord A. Bergquist, Monterey Park, and John A. Over, Arcadia, Calift, assignors t0 Pendleton Tool Industries, Inc., Los Angeles, Calif., a corporation of Delaware Filed Mar. 20, 1964, Ser. No. 353,493 4 Claims. (Cl. 8163.1)

The present invention relates generally to hand tools and especially to ratchet wrenches and the like having in ternal pawl means shiftable between two operational positions to obtain a torque drive in a selected one of two directions.

Some designs of such wrenches involve springs actuating the pawls. The springs are at times unsatisfactory because they fail to operate properly, either through breakage or loss of strength. Replacements for the springs are often very difiicult to secure.

Other designs of tools of this character are unsatisfactory as they are complex, have small breakableparts, are hard to disassemble for cleaning and maintenance, and then reassemble.

Thus it is a general object of the present invention to provide a simplified form of pawl shifting mechanism for a wrench or the like, that is strong, reliable in operation, and economical to manufacture.

It is also an object of the invention to provide a new and improved design for the driven member and the pawl actuating means carried thereby permitting easy assembly and disassembly without special tools.

A further object is to provide a new and novel design for the driven member and the pawl actuator in which these members are confined to operational movements while mounted within the wrench handle.

The above objects of the present invention are achieved in a ratchet wrench of the type comprising a driving head having a handle by which the wrench is manipulated; a driven body rotatable within a circular opening in the head and including a work-engaging member, normally integral with the body; andpawl means carried by the body and movable relative thereto between two operative positions in each of which the pawl means engage the driving head to establish a torque transmitting relation between the head and the body in one direction of drive and ratchet in the opposite direction. By selecting one of the two operative positions to be occupied by the pawl means, the torque transmitting relation can be established for either selected direction of torque drive by the handle relative to the body, a ratchet relation being effected for i the reverse direction whereby the handle may be moved repeatedly back and forth through short arcs in order to advance a driven tool.

The invention more particularly comprehends a pawl actuator which is angularly movable relative to the body in order to shift the pawl means from one position to the other, said angular movement of the actuator being limited by engagement of the pawl means with the body at each of said two positions; and locking means comprising interengaging elements on the body and on the pawl actuator holdingthe body and actuator against relative axial displacement, said interengaging elements being disengageable upon angular movement of the actuator beyond the normal range of movement required to shift the pawl means between said two positions.

How the above objects and advantages of the present invention, as well as others not specifically mentioned, are attained will be better understood by reference to the following description and to the annexed drawing, in which:

3,299,969 Patented Dec. 13, 1966 FIG. 1 is a perspective of a ratchet wrench embodying the present invention;

FIG. 2 is an exploded view of the ratchet wrench comprising the present invention, with a portion of the handle broken away;

FIG. 3 is a plan view of the head of the ratchet wrench with the pawl actuator disc removed;

FIG. 4 is a section through the head of the wrench taken on two different axial planes, as on the line 44 in FIG. 3;

FIG. 5 is a bottom plan view of the pawl actuator disc; and

FIG. 6 is a plan view of the driven body and pawl means removed from the wrench head, showing the possible extra range of movement of the pawls when out of the head.

Referring now to the drawing, there is shown in FIG. l a perspective of the entire wrench, indicated generally at 19. The wrench includes a generally circular head 11 to which is attached handle 12. As may be seen by reference to FIGS. 2 and 4, the head 11 is a hollow member having a cylindrical opening passing through the head.

Around the periphery of one portion of .this opening in the wrench head there is arranged a series of axially extending, circumferentially spaced serrations or teeth 14 which are preferably formed integrally with the wrench head. Just above the teeth 14, as viewed in FIG. 2, the wrench head is counterbored to provide an upper cylindrical section 15 of larger diameter, thus providing a shoulder 16 at one end of the teeth and between the two sections of the bore of different diameters.

Wrench head 11 is the driving member of the wrench, While the inner driven member is body 20 which is located within the opening in the wrench head. The body 20 is provided with shank 21 which is a work-engaging member and is normally adapted to receive a socket or other fitting or adapter which receives a nut, screwhead, or the like.

Body 20 has an upper end portion 22 of relatively enlarged diameter, the projecting underside of which provides a shoulder which engages shoulder 16 on the head to form a thrust bearing that serves to limit in one direction the travel of the body into the wrench head. The body and parts attached to it, as will become apparent, are held in assembled position within the wrench head by snap ring 23 which fits within a groove 24 cut in the body at such a position that the ring also engages the underside of the wrench head, as may be seen in FIG. 4.

Extending axially into the body from the upper end thereof are two slots 25 which are parallel to each other and are located, respectively, at opposite sides of the axis of rotation of body 20. As may be seen particularly in FIG. 3, the two slots 25 extend entirely across the body and thus are open at both ends.

Slidably disposed in each slot 25 is a pawl 26. Each pawl 26 is symmetrical about a median transverse plane and thus may be described as double-ended. That is, at each end of each pawl, there are formed teeth 27 which are engageable with teeth 14 on the wrench head. Each pawl 26 is shorter than the slot 25 in which it slides so that the teeth at only one end of the pawl can engage the teeth on the head at any given time.

Each pawl 26 is slidable longitudinally within its associated slot 25 between two terminal positions since travel of the pawl is limited by engagement of a toothed end face with teeth 14 on the wrench head. At each of these terminal or operative positions, the pawl means provided by the two individual pawls 26 provide a torquetransmitting connection between the wrench head and the inner body that drives the inner body to rotate it with the wrench head. The shape of the teeth on the pawl and on the wrench head is such that for one relative direction of rotation of the wrench head with respect to the body, the meshing teeth drivingly engage each other to establish this torque-transmitting relation; but for the opposite direction of rotation, the teeth on the pawl and on the wrench cam the pawl inwardly to establish a ratchet relation so that the wrench head turns independently of the body. Thus when the two pawls are disposed at opposite ends of their associated slots as shown in FIG. 3, the pawl means are adapted to transmit clockwise torque from the wrench head to the body and thus to work-engaging member 21. When the pawls are shifted to the other ends of their associated slots, they are then conditioned for transmission of torque in the opposite direction of rotation of handle 12, that is, counterclockwise rotation of the wrench head with the body and work-engaging member 21.

At the end of teeth 14 removed from shoulder 16, there is set into the body a bearing ring 29 (FIG. 4) which is preferably a press fit in the body. This ring engages the periphery of body 20 near the lower end thereof to locate the body centrally of the opening in handle 10. This bearing cooperate with the similar radial bearing provided at the other end of body 20 by the periphery of body section 22 engaging the surrounding inner surface of wrench head 11. These two bearings keep the driven bodyin the desired axial alignment with respect to the driving head 11 and prevent damaging contact of the body with the surrounding teeth 14.

It is preferable to provide detent means which resiliently hold the two pawls in either of these terminal driving positions. Such detent means comprise a helical coil spring 30 mounted in a transverse bore 31 in that central portion of the body disposed between the two slots 25. At each end of spring 30 is a ball 32 which is urged by the spring into one of two angular notches 34 in the inner face of the pawl. The detent means tend to hold the pawls in their terminal positions; but yield upon application of a slight endwise force to the pawls to shift them from either terminal position to the other.

To effect this shifting of the pawls between terminal operative positions, there is provided pawl actuator means in the form of disc 40 which is mounted for angular movement relative to and concentric with inner body 20. As may be seen in FIG. 2, the upper end of body 20 is provided with a generally circular recess which opens to and is above slots 25; and actuator 40 has a reduced diameter body portion 40a adapted to fit in this recess.

Pawl actuator 40 and the two pawls 26 are drivingly interconnected by any suitable design of interfitting configurations, a typical and preferred form of which includes the two pins 41 on actuator 40 and the centrally located slots 42 in the pawls. Slots 42 are recessed into the upper face of each of the pawls and extend transversely of the pawls, preferably being open at their ends. The two pins 41 are located in diametrically spaced positions on the underside of actuator disc 40. Thus when actuator disc 40 is within the recessed upper end of body 20, as shown in FIG. 4, a pin 41 extends downwardly into slot 42 of each of the two pawls. The pins and the pawls can be engaged and disengaged by relative axial movement of the actuator and the body with the pawls in it.

On its upper or outside face, the pawl actuator is provided with a handle 44 by which the actuator may be manually turned. This causes Pins 41 to engage the side faces of slots 42 and shift the pawls longitudinally within their respective slots 25. It will be apparent that the angular movement of the pawl actuator is limited at each end of its travel by engagement of the pawls with the head of the wrench.

Actuator 40 enters the center circular recess in the upper end of body 20 by movement in an axial direction relative to the body. In order to hold the parts in the assembled position shown in FIG. 4, locking means are provided holding the body and actuator against relative axial displacement in a direction to separate these two parts. Such locking means comprise interengaging elements on the body and on the pawl actuator which throughout the normal range of travel of the actuator are eiiective to hold the actuator against axial removal from the body.

The interengaging elements of these locking means comprise a pair a of diametrically disposed lugs 50 of the actuator disc, as may be seen in FIG. 5. These lugs 5t) project radially outward from the cylindrical portion 40a of the disc which fits Within the cylindrical recess in the upper end of body 20. As may be seen particularly in FIG. 2, the wall around the central recess in the body is under cut to provide a groove 52 of a diameter to receive the two lugs 50. Above the groove is created an overhanging shoulder 53 which engages the lugs to hold the actuator and body against relative axial displacement.

Groove 52 is not continuous since it is intersected by slots 25, cutting the groove into sections. The effect is to provide diametrically opposite overhanging shoulders 53 each engaged by a lug 50. The sections of the groove between slots 25 open at their ends into the slots 25; and advantage is taken of this to enable disengagement of lugs 50 from shoulders 53. The normal range of angular movement of the pawl actuator while keeping the lugs under the shoulder is indicated by the angle 55 in FIG. 6. When the range of pawl movement is not limited by engagement with the body, as will be explained, the actuator may be turned through an additional angle 56, indicated in FIG. 6, at either side of the normal range 55, to bring the lugs 50 into slots 25.

When snap ring 23 is pried out of groove 24 and removed from the head, the assembly consisting chiefly of body 20, pawl actuator 40, and the two pawls 26 carried by the body may be lifted, as a unit, axially out of the cylindrical opening in wrench head 11. Since the pawls are now no longer confined endwise by the wrench head, they are able to slide within slots 25 beyond their terminal operational positions which, as shown in FIG. 3, were determined by contact of the pawls with the surrounding wrench head. The pawls can now move to extended positions as shown in FIG. 6 which are beyond their normal range of movement when confined by the wrench head. The pawl actuator likewise now may be rotated angularly through a greater range of movement than before, by the amount of angle 56, in order to bring the pawls to the position shown in FIG. 6. In this position, lugs 50 are no longer confined against axial movement by downwardly facing shoulders 53 but are now positioned in slots 25; and now actuator 40 can be lifted axially relative to body 20 to disengage the pawl actuator from the body and from the pawls. This same movement removes pins 41 from the slots in the pawls. The pawls can now be removed from the head. Likewise the detent means can be removed, quickly and completely disassembling the wrench without requiring any tools. The separable parts are those shown in FIG. 2. Of course, the wrench can be re-assembled by reversing the sequence of operations. I

From the foregoing description, it will become evident that various changes in the detailed arrangement and construction of the parts comprising the improved ratchet wrench may be made without departing from the spirit and scope of theinvention. Accordingly, it is to be understood that the foregoing description is considered as being illustrative of, rather than limitative upon, the invention as defined by the appended claims.

What is claimed is:

1. A ratchet wrench, comprising:

a driving head having a handle;

a driven body rotatable within the head and includin a work-engaging member;

pawl means carried by the body and movable between two positions in each of which the pawl means engage the driving head to establish a torque transmitting relation between the head and the body in one direction of torque drive by the head and ratchet in the opposite direction;

a pawl actuator angularly movable to shift the pawl means from one position to the other, said angular movement normally being limited by said engagement of the pawl means and with the driving head;

a pair of diametrically disposed, arcuate shaped, over- 2. A ratchet wrench, comprising: a driving head having a handle; a driven body rotatable within the head and including a work-engaging member;

said body having a pair of parallel slots extending across the body and disposed respectively at opposite sides of the axis of rotation of the body;

a double-ended pawl in each of said slots and movable therein between two limiting positions in each of which the pawl engages the head to transmit torque to the body in one direction of torque drive by the head and ratchets in the opposite direction;

pawl actuator engaging both pawls and angularly movable to shift the two pawls simultaneously between said positions, the normal range of movement of the actuator being limited by said engagement of the pawls with the driving head;

and locking means comprising interengaging elements on the body and on the pawl actuator holding the body and actuator against relative axial displacement within the range of travel of the actuator when shifting the pawl means between said two positions, said elements being disengageable upon angular movement of the actuator relative to the body beyond the normal range of movement required to shift the pawls between said two positions.

3. A ratchet wrench as in claim 4 in. which the locking means comprise shoulder means on the body and outwardly extending lugs on the pawl actuator engaging the shoulder means to hold the actuator against axial displacement relative to the body,

and in which the pawls are free to move in said slots beyond said positions when the body is out of the head, permitting the actuator to rotate beyond said normal range to a position at which the lugs are beyond the shoulder means and in said slots freeing the actuator for axial displacement relative to the body.

4. A ratchet wrench as in claim 1 in which the body has at least one straight slot open at the ends and at one side;

and in which the pawl means includes at least one pawl movable in the slot to move into said positions engaging the driving head in response to said normal range of travel of the actuator;

said pawl being movable in the slot beyond the head engaging positions when unrestrained by the head.

References Cited by the Examiner UNITED STATES PATENTS 1,929,310 10/ 1933 Greve 220-40 2,744,432 5/ 1956 Rueb 81--62 2,799,194 7/1957 Hall 81--63 2,982,161 5/1961 Angquist et a1. 81-60 WILLIAM FELDMAN, Primary Examiner.

WEIDENFELD, Assistant Eq cam il er,

Claims

1. A RATCHET WRENCH, COMPRISING: A DRIVING HEAD HAVING A HANDLE; A DRVEN BODY BODY ROTATABLE WITHIN THE HEAD AND INCLUDING A WORK-ENGAGING MEMBER; PAWL MEANS CARRIED BY THE BODY AND MOVABLE BETWEEN TWO POSITIONS IN EACH OF WHICH THE PAWL MEANS ENGAGE THE DRIVING HEAD TO ESTABLISH A TORQUE TRANSMITTING RELATION BETWEEN THE HEAD AND THE BODY IN ONE DIRECTION OF TORQUE DRIVE BY THE HEAD AND RATCHET IN THE OPPOSITE DIRECTION; A PAWL ACTUATOR ANGULARLY MOVABLE TO SHIFT THE PAWL MEANS FROM ONE POSITION TO THE OTHER, SAID ANGULAR MOVEMENT NORMALLY BEING LIMITED BY SAID ENGAGEMENT OF THE PAWL MEANS AND WITH THE DRIVING HEAD; A PAIR OF DIAMETRICALLY DISPOSED, ARCUATE SHAPED, OVERHANGING SHOULDERS ON THE BODY: AND A PAIR OF RADIALLY PROJECTING LUGS ON THE ACTUATOR AT DIAMETRICALLY SPACED POSITIONS ENGAGEABLE WITH SAID SHOULDERS TO HOLD THE BODY AND PAWL ACTUATOR AGAINST AXIAL DISPLACEMENT; SAID LUGS BEING MOVABLE BEYOND AND OUT OF ENGAGEMENT WITH THE SHOULDERS BY SAID ANGULAR MOVEMENT OF THE ACTUATOR BEYOND THAT MOVEMENT REQUIRED TO SHIFT THE PAWL MEANS BETWEEN SAID TWO POSITIONS.