US2688269A - Reciprocatory plunger type ratchet wrench - Google Patents

Description

Sept 154 W. 1F. LUDWHG RECIPROCATORY P-LUNGER TYPE RATCHET WRENCH Filed Jan. 18, 1952 INVENTOR rf. www@ Mmmm ATTORNEY Patented Sept. 7, 1954 RECIPROCATORY PLUNGER TYPE RATCHET WRENCH William F. Ludwig, Parma, Ohio Application January 18, 1952, Serial No. 267,057

The present invention relates to improvements in a reciprocatory plunger type ratchet wrench and has for an object the provision of an improved device of this kind which is especially adapted for starting screws and nuts in the direction of their tightened positions in places where it is hard or impossible to reach `by hand or with conventional tools.

Another object of the present invention is to provide an improved wrench which is capable of being used to tighten nuts, screws or the like by reciprocating the wrench without removing it from the head of the nut or screws.

A further object of the present invention is to provide an improved structure in which the nut holder and ratchet are made integral and are detachably mounted on the body portion of the wrench so that nut holders of various sizes and shapes may be selectively mounted on the body of the wrench and in the event the teeth of the ratchet become worn or broken a new holder and ratchet unit may be substituted for the old one.

The present invention aims to provide an im proved wrench of this character which comprises relatively few parts, is economical to manufacture, has a minimum of working parts and is compact.

With the foregoing and other objects in view, the invention will be hereinafter more fully described and more particularly pointed out in the appended claims.

In the drawings, in which the same parts are denoted by the same reference numerals throughout the several views,

Figure 1 is a perspective view of an improved wrench constructed in accordance with the present invention,

Figure 2 is an exploded perspective view of the body and the plunger shaft of the improved wrench,

Figure 3 is a longitudinal sectional view taken on the line 3-3 of Figure 1, and

Figure 4 is a sectional view taken on the line 4-4 of Figure 1.

Referring more particularly to the drawings, I indicates the main body portion of the wrench which may be substantially T-shaped, the arms II of which may be formed integral with the body I0 or may be secured to one end thereof as by welding or the like. The opposite end portion of the body I0 may be of slightly greater width than the major portion of the body and is provided with an opening I2.

A combined nut holder and ratchet member,

2 Claims. (Cl. 81-61) generally indicated at I3, is adapted to be detachably mounted on the enlarged end portion of the body Ill and comprises a cup shaped nut holder I4 and ratchet teeth I5. The nut holder I4 may be of any desired size or configuration for receiving the head I6 of a screw I1 or the like. In the present illustration the cup shaped nut holder I4 is hexagonal in shape so as to accommodate the similarly shaped head I6 of the screw Il. The ratchet teeth I5 are formed on the outer face of the cup shaped nut holder I4 adjacent the closed end I8 thereof and may be formed integrally therewith or fixed thereto in any suitable manner. The closed end I8 of the nut holder I4 has an opening I9 therethrough which is adapted to be brought into registry with the opening I2 of the body IIl when the member I3 is mounted on the bodyl I0.

A bolt 20 extends through the aligned openings I2 and I9 and its threaded end portion 2| extends beyond the body I0 to receive a friction washer 22 and a nut 23 which when screwed home will bind the washer 22 between itself and the body Il] and will draw the head 23 of the bolt 20 against the inner face of the bottom I8 of the nut holder I4. The head 23 of the bolt 20 may be provided with a kerf 24 for receiving a screw driver or the like for facilitating the tightening of the bolt 20 and the nut 23.

A combined plunger shaft and pawl member, generally indicated at 25, comprises an intermediate shank 26, guide stem 2l and a pawl 28. The guide stem 21 is provided by reducing the width of one end portion of the member 25 which will form shoulders 29. The guide stem 21 is adapted to be slidably received by a slot 30 which is formed in a guide 3| carried by the intermediate portion of the arms Il. The guide 3l extends from the upper edge of the arms II towards the body Ill and extends therebeyond. The shank 26 is provided with an elongated slot 32 which has a sliding engagement with a guide stud 33 which is threadedly received by an opening 34 in the body I0.

A thumb knob 35 is mounted on the free end portion of the stem 2l and its upper surface may be concave to afford a purchase for the thumb of the user of the wrench. A coil spring 36 encircles the guide stem 2'I and has its opposite ends abutting the guide 3| and the knob 35 for normally urging the pawl 28 in a direction away from the ratchet teeth I5. A at spring 3'I has one end portion frictionally held by the lingers 38, 39 and 40 which may be formed integrally with o r fixed inrany suitable manner on one edge of the body portion I0. The end lingers 3 38 and 4G are in substantial alignment longitudinally of the body I and the intermediate finger 39 is inwardly laterally offset from the iingers 38 and 40.

The end portion of the spring 31 which is retained by the iingers has its inner face engaging the outer face of the intermediate finger 39 and its outer face engaging the inner faces of the end fingers 38 and 43. This arrangement is suflicient so that the spring 31 will be frictionally held in position by the lingers, but, if desirable, the spring may be secured to the iingers by welding or in any other suitable manner.

The edge portion of the shank 26 adjacent the iingers 38, 39 and 4U is cut away to accommodate the fingers and the spring 3i and the free end portion of the spring 3l bears against the edge of the cut away portion of the shank 26 adjacent the pawl 28 for urging the nose of the pawl into firm engagement with the teeth of the ratchet. A substantially U-shaped retaining member 4I has its side 42 secured to the outer face of the body I0 opposite to the cut away portion of the shank 2B. The connecting portion 43 of the member 4I extends across the edges of the body I0 and shank 23 opposite to the fingers and the other side 44 of the member 4I overlies and is spaced from the inner face of the body I0 and engages the shank 25 adjacent the pawl 28.

In the operation of the device the proper sized and shaped member I3 is secured to the body portion I0 by bolt 23 and nut 23. The head I6 of the screw I'I will now be inserted in the nut holder I4 and the screw may be brought into registry with the threaded opening of the machineinto which it is desired to insert the screw. This may be accomplished regardless of the location of the screw opening since the body I and the shank 26 are relatively narrow and elongated. The operator will place his thumb on the concave surface of the knob 35 and his iirst two fingers in engagement with the arms I I on the edges thereof remote from the knob 35. By pressing on the knob with his thumb the member 25 will be moved longitudinally of the member I3 against the action of the coil spring 35 so that the pawl 28 which is in engagement With one of the teeth I5 will cause the nut holder I4 to rotate one step in a direction which will cause tightening movement of the screw I'I.

The movement of the member under the pressure of the thumb will be limited by the end 0f the slot 32 which is adjacent the knob 35 engaging the stud 33. Lateral shifting of the shank 26 so that the pawl 28 may clear the next tooth I5 of the ratchet is permitted since the shank 26 is cut away at a point opposite to the retaining member 4I. There is sunicient loose play between the slot 30 and the guide stem 21 and the slot 32 and stud 33 so that the shank 28 can pivot about the stud 33 during the lateral shifting of the shank. Upon release of the thumb from the knob 35 the spring 36 will return the member 25 to its original position. The shoulders 29 will engage the inner face of the guide 3| and the end wall of the slot 32 remote from the shoulders 29 will abut the stud 33 and restrict the movement of the member 25 under the influence of the spring 36. The parts will then be in position for another partial rotation of the nut holder I4 by the pawl 28. The member 25 will be guided in its movement by the guide 3| and the retaining member 4I and the flat spring 31 will constantly urge the nose of the pawl 28 into iirm engagement with the teeth of the ratchet I5. By

repeating the movement of the member 25 the screw I1 may be easily screwed down tight.

It will also be noted that the device may be used in the form of a ratchet wrench for tightening screw I'I or the like Without removing the nut holder I4 from the head I5 of the screw. During this operation the friction washer 22 and the pawl 28 will cooperate to prevent relative movement between the member I3 and the body I0 so that the swinging movement imparted to the body IIJ by the operator will be communicated to the nut holder I4 and hence to the screw II, during the tightening movement of the wrench. In other Words, the entire wrench is swung by the hand of the operator about the longitudinal axis of the screw during the tightening movement of the device and on the non-tightening return stroke the pawl 28 is free to click over the ratchet teeth I5 so that the body ID and plunger shaft 25 will swing about the longitudinal axis of the screw I1 and move with respect to the nut holder I4 to their original positions.

On the return or non-working swinging movement of the body ID the resistance of the screw to being unscrewed will overcome the frictional resistance of the washer 22 and the pawl 28 will ride over the teeth of the ratchet I5 so that the body I0 may be moved relative to the nut holder This wrench is adapted to be used on nuts, screws and the like on any kind of machinery and is especially adaptable for use on typewriters and adding machines.

It is obvious that various changes and modifications may be made in the details of construction and design of the above speciiically described embodiment of this invention without departing from the spirit thereof, such changes and modiiications being restricted only by the scope of the following claims.

What I claim is:

1. A wrench comprising a body portion, an integral nut holder and ratchet detachably and rotatably mounted on said body portion, an integral plunger shaft and pawl member mounted for longitudinal reciprocating and lateral sliding movement on said body portion and comprising a pawl engaging said ratchet and a shank, guide means for guiding said plunger shaft, a plurality of fingers on said body portion adjacent said pawl, and resilient means held by said fingers and bearing against said pawl to urge the pawl into firm engagement with said ratchet, said guide means having a portion engaging said shank to prevent separation of the Shank and body portion and to prevent escape of the pawl from the ratchet.

2. A wrench comprising a body portion, an integral nut holder and ratchet detachably and rotatably mounted on said body portion, an integral plunger shaft and pawl member mounted for longitudinal reciprocating and lateral sliding movement on said body portion and comprising a pawl engaging said ratchet and a shank, longitudinally spaced apart guides on said body portion for supporting and guiding said plunger shaft, a guide stem at one end of said plunger shaft of less width than said shank to provide shoulders on said shank, one of said guides having a slot for slidably receiving therethrough said stem, a thumb knob on the free end of said stem for receiving the thumb of an operator for moving said plunger shaft to cause the pawl to rotate the ratchet and nut holder, a coil spring embracing said stem and confined between said knob and the slotted guide for returning said plunger 5 shaft to its initial position after being moved by the use of the thumb knob, said shoulders engaging said slotted guide to limit the return movement of said plunger shaft under the influence of said spring, a plurality of lingers on said body portion adjacent the other of said guides and said paWl, and a fiat spring having one end portion frictionally held by said ngers and its opposite end portion bearing against said pawl to urge the paWl into rm engagement with said ratchet, said other guide having a portion engaging said shank to prevent separation of the shank and body portion and to prevent escape of the pawl from the ratchet.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date King Dec. 27, 1898 Hutt et a1. July 10, 1900 Bennett Sept. 18, 1906 McEwen June 27, 1916 Helbling June 2, 1931 Rose Sept. 4, 1934 Dalquist Feb. 20, 1940

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