US2914979A

US2914979A - Open-end wrench ratchetable on workpiece

Info

Publication number: US2914979A
Application number: US597031A
Authority: US
Inventors: Abraham S Weinstein
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-07-10
Filing date: 1956-07-10
Publication date: 1959-12-01
Anticipated expiration: 1976-12-01

Description

Dec. 1, 1959 A. s. WElNSTElN 2,914,979

OPEN-END WRENCH RATCHETABLE 0N WORKPIECE Filed July 10, 1956 1N VEN TOR.

443%! %Mm m WRENCH RATCHETABLE N WORKPIECE 'AbrahamS. Weinstein, Broo'liline, Mass. Application July 10,1956, Serial No. 597,031

3, Claims. (Cl. 81-111) OPEN-END The present invention relates to an improved structure in a ratchet wrench.

In the art of manufacturing wrenches there is a constant desire to improve the structure of wrenches 'so that they will operate more efficiently and permit the operator greater control over the elements with which the wrench is being used.

.In the present invention a ratchet wrench is it provided which permits the operator, while hold.ng the wrench in one hand, to selectively tighten or-clamp the wrench to a nut or alternately to release the jaws of the wrench from around the nut so as to rotate the wrench to a new and more desired position.

The present invention also provides a ratchet wrench structure inwhich retaining plates are provided to prevent the wrench from slipping from the nut,

The present invention also provides a ratchetable so designed as to permit a substantial application of torque to a nut being ti'ghtened, a;minimum amount of forcebeing required from the operator to prevent ratcheting of the jaws.

In the present invention the control of the jaws is maintained through thumb pressure in such a way as to be quite convenient for operation of the-wrench.

Further, in'the present invention the jaws are so constructed as to permit their ready adjustment-fornuts of different sizes, with each jaw being formed with teeth adapted to clamp a nut every 30. The jaws are also slightly spring-tensionedtowards one another when they 'are' not rigidly clamped in position so as to permit a nominal amount of holding force to be applied by the jaws to a nut. This slight spring-tensioning force is superseded 'by' the action of the lever mechanism which blocks one of the jaws in position. Further, under the arrangement of the present invention, when the operator applies thumb pressure to the blocking mechanism, the spring-closed jaws will be held against opening movement by a substantial force, thus providing in addition to a blocking action on one of the jaws, apositive gripping or clamping effect on the nut.

These objects of the present invention are attained in a structure which provides a pair of jaws at either end of the unit with bothsets of jaws being operable by a single actuator. In this structure the entire mecha nism is contained 'within a very fiat and compact strucwrench in which the jaws are controlled by a lever action Patented Dec. 1, 1959 ice ing the jaws in the positions that they would assume on an oversized nut, and showing the jaw-blocking mechanism in retracted position.

In the embodiment of the present invention, as illustrated in Figures 1, 2 and 3, there are provided two opposing face plates 1 and 2 between which the operating mechanism for the jaws of the present invention are substantially entirely located. Two

pairsof jaws

3 and 4 and 5 and 6 project outwardly from the areas between the ends of the plates 1 and 2. As this wrench is symmetrical on either side of its center line, the description hereinafter will refer only to one side of the structure;

but it should be understood that it is descriptive of both sides with the exception that the jaws of one side may be adapted to grip a nut of different size than the jaws of the other side.

The jaw 3 is formed with an inner serrated portion 7 adapted to cooperate with a serrated or toothed portion 8 of the jaw 4 to grip a nut 9 at selected positions, preferably 30' apart. The jaw 3 is pivoted between the plates 1 and2 by a pin 11 which is suitably anchored at either end inthe plates 1 andZ. If desired, this pin 11, as well as the other pins hereinafter referred to, may be formed of a screw or threaded pin which threads suitably into each of the plates 1 and 2 to act as a pivot or support. The jaw 3 has an inwardly extending lever arm 12 which terminates in a concave surface 13 and which is somewhat laterally offset from the exposed portion of the jaw. I V

The jaw 4 is pivoted between the plates 1 and 2 by a pin 14 at the inner end of the jaw. An opening in the jaw at 15 is provided with a series of stepped projections 16. These stepped projections 16 are adapted to successively engage-a tooth 17 of a locking member 18 so that the jaw 4 may be selectiveiy positioned in any one of three different positions, each at a different distance from the jaw 3. The locking member 18 projects through an elongate slot 19 in the plate 2, the elongate axis of saidslot forming an acute angle with a line passing through the apexes of said stepped projections 16, and is provided with an accessible serrated surface 20 for selective movement of the jaw 4. The jaw 4 is maintained in' the particular position selected by a spring member 21 which has free ends extending outwardly from 'a portion turned about a pin 22 to engage the jaw 4 attwo different positions as illustrated.

A blocking or latching lever 25 is pivotally positioned on a pin 26 and tapers inwardly to an end 27. The tapered end 27 is positioned and shaped to engage the concave surface 13 upon pivoting of the lever 25. When the end 27 engages the concave surface 13, the jaw 3 which has been moved by an outer leg of a spring 29 to its innermost position as indicated by the dotted line '28 is blocked in such position. This lever 25 is normally maintained in a retracted position as shown in full lines in Figure 3, bythe action of an inner leg of the spring 29 which also maintains the jaw 3 in the position 23 illustrated in Figure 3. This spring 29 is anchored by spaced pins 30 and 31 which swingably support the outer and inner legs for continuous contact at their free ends, respectively with the lever section 12 of the jaw 3 and with the side of the lever 25.

When the lever 25 moves into engagement with the surface 13, it acts against the tension of the inner legs of the spring 29. The outer leg of the spring 29, however, continuously biases the jaw 3 to a'nut-gripping position so that when the lever 25 is moved against the concave surface 13, the jaw 3 will be blocked in such position. When the lever 25 is disengaged from the surface 13 and is in the retracted position indicated in full lines in Figure 3, the jaw 3 is free for limited movement about the pin 11 against the tension of the outer leg of the spring 29,

thus permitting a nut between the jaws, during a reverse movement of the wrench to move the jaw 3 to its outermost position indicated at 35. Because the jaw 3 may be moved by a nut when the lever 25 is disengaged, the jaws 3 and 4 may rotate a nut 9 step-by-step without removal of the nut from between the jaws, each reverse swing of the wrench being permitted by the simple expedient of releasing the lever 25.

The lever 25 is in turn controlled by a second lever element 37 which is pivoted at 38. This lever element 37 has'a surface 39 engageable with that side of the lever 25 opposite the inner leg of the spring 29. The lever 37 has an arcuate surface 40 and a tongue section 41 substantially complementary to a side portion of a finger-controlled member 42. This finger-controlled member 42 is positioned between the plates 1 and 2 with a portion 43 projecting outwardly therefrom and adapted to be engaged by a thumb or finger. The member 42 is mounted for slidable longitudinal movement by

pins

44 and 45 which respectively are mounted in an open-end slot 46 and a closed slot 47. Thus, when the member 42 ismoved inwardly by the operator from the position illustrated in solid outline in Figure 3 to a position indicated by the dotted outline 49, the lever arm 37 will be moved in such a manner as to cause the lever 25 to engage the surface 13, thus blocking the jaw 3 in any closed position to which it has been moved by the spring 29, such as its innermost position at 28. It will be observed that because of the lever proportioning, a very slight amount of thumb or finger pressure on the member 42 is required to rigidly hold the jaw 3 in a latched position.

If there were a nut 9 positioned between the jaws 3 and 4, it is clear that the spring 29 would close the jaws thereon, and that squeezing the member 42 would block the jaw 3 against opening movement and would thus secure the jaws 3 and 4 about the nut. When a reverse movement of the wrench is desired so as to obtain a fresh grip on the nut, the operator need only release the pressure on the member 42 to permit the inner leg of the spring 29 to automatically move the lever 25 to its retracted position, whereupon the jaw 3 is free to be pivoted by the nut against the jaws-closing tension of the outer leg of the spring 29 upon the reverse swing of the wrench around the nut.

A pair of

spacer blocks

51 and 52 are secured by

pins

53, 54, 55 and 56 between the plates 1 and 2 and afford a certain amount of protection to the mechanism from external sources. The plates 1 and 2 may also be supported in spaced relations with one another by a pin 57 located between the jaws 3 and 4. Secured to the outside of plate 2 at one end and to plate 1 at the other end are duplicate locating members 60 and 61. The member 60 is pivotally secured to the plate 2 by the same pin 11 supporting the jaw 3 and is pivotally rotatable about this pin 11. This member has two

legs

62 and 63 angularly positioned to one another and extending from its pivoted section. The leg or section 63 is adapted to be pivoted over the open portion between the jaws 3 and 4 and is adapted to be secured either in this position or in a position in which the leg 63 is located entirely over the plate 2 by the engagement of a boss 64 with openings 65 and 66 respectively in the plate 2. Thus, by moving the member 62 so the boss 64 engages the hole 65, the leg 63 may overlap the nut 9 and thus prevent the wrench from accidentally slipping from the nut 9 at least in a direction in which the member 62 is moved towards the nut 9. For this purpose the element or member 62 should have some degree of resilience to permit the boss 64 to move into or out of the openings 65 and 66.

It should be noted that the jaws of the wrench are particularly adapted to grip worn bolts with a continuously applied substantial pressure. This action is obtained 4 through the continuous closing pressure applied to the jaw 3 by the outer leg of the spring 29, and to the latch1n g action of the lever system. When the member 42 1s squeezed to a jaw-blocking position, the jaws are not limited to a single-sized gap as is the case with the conventional wrench, but rather will press closely against a bolthead or nut regardless of any differences in size caused by manufacturing tolerances, wear, etc.

In this connection itis to be noted that the lever 25 to effect blocking action on the jaw 3 will make contact with the surface 13 at a position which depends on the size of a nut embraced by the jaws.

Having now described my invention, I claim:

1. A ratchet wrench comprising. a pair of jaws, one of said jaws having a lever-arm extension, means supporting said jaws, said one jaw being pivotally supported, an actuating member mounted for slidable movement and having a projecting surface, a lever system comprising a pair of pivotally mounted interacting levers, one of said levers having a portion operatively engageable by said surface and the other of said levers having a portion adapted to be pivoted into blocking engagement with said extension, spring means engaging said extension and said other lever and normally maintaning said other lever in a nonengaged position and said one jaw tensioned toward the other of said pair of jaws, said arm extension and said other lever having adjacent ends adapted to describe intersecting arcs when free to pivot, and said arm extens on being provided with a concave surface angularly intersecting the are described by said other lever, whereby when said other lever is actuated, said spring-closed jaw will be blocked in the position to which it has been moved by said spring.

2. A ratchet wrench comprising a pair of jaws, one of said jaws having a lever-arm extension, means supporting said jaws, said one jaw being pivotally supported, an actuating membermounted for slidable movement and having a projecting surface, a lever system comprising a pair of pivotally mounted interacting levers, one of said levers having a portion operatively engageable by said surface and the other of said levers having a portion adapted to be pivoted into blocking engagement with said extension, and spring means engaging said extension and said other lever and normally maintaining said other lever in a nonengaged position, and said one jaw tensioned towards the other of said pair of jaws, said spring means comprising an elongated spring mounted intermediate its ends, one end bearing against said other lever and the other end against said extension.

3. A ratchet wrench comprising, a pair of jaws, one of said jaws having a lever-arm extension, means supporting said jaws, a lever having a portion adapted to be pivoted into blocking engagement with said extension, spring means engaging said extension and said lever and normally maintaining said lever in a non-engaged position and said other jaw tensioned toward said one jaw, said arm extension and said lever having adjacent ends adapted to describe intersecting arcs when free to pivot, said arm extension being provided with a concave surface angularly intersecting the are described by said lever, whereby when said lever is actuated, said spring closed jaw will be blocked in position to which it has been moved by said spring, and means for actuating said lever.

References Cited in the file of this patent UNITED STATES PATENTS 1,716,382 Nickerson June 11, 1 2,426,191 Feiring Aug. 26, 1947 FOREIGN PATENTS 3,886 (heat Britain Aug. 15, 1882