US3541898A - Ratchet wrench - Google Patents

Description

Nov. 24, 1970 M. M. MURATA RATCHET WRENCH Filed Aug. 30, 1968 m m w N I MAE/6 M, MMQA United States Patent 3,541,898 RATCHET WRENCH Mark M. Murata, Kaneohe, Hawaii (Box 275, FPO, Seattle, Wash. 98766) Filed Aug. 30, 1968, Ser. No. 756,491 Int. Cl. B25b 13/28 US. Cl. 81-111 2 Claims ABSTRACT OF THE DISCLOSURE An adjustable ratchet wrench consisting of a housing in which a first wrench jaw is slidably-mounted and is gearingly-engaged by a manually-operated adjusting worm journalled in the housing. A second jaw is pivoted to the housing and is biased toward the first jaw by a fiat spring. A handle is pivoted to the housing and has a drive notch engageable with a drive lug on the inner end of the pivoted second jaw. In one direction of rotation the handle rigidly interlocks with the drive lug and holds the pivoted jaw rigidly in parallel relation to the first jaw. In the opposite direction of rotation of the handle, the pivoted jaw can yield against the tension of the spring to allow the jaws to slip from one set of opposed flat surfaces of an object between the jaws to the next adjacent set of opposed fiat surfaces of the object, thereby providing a ratchet action.

This invention relates to wrenches, and more particularly to wrenches of the open-end adjustable-jaw type.

A main object of the invention is to provide a novel and improved adjustable open-end wrench having ratchet action, the wrench being relatively simple in construction, being easy to operate, and being especially useful in turning nuts or bolt-heads in locations Where space is very limited.

A further object of the invention is to provide an improved adjustable ratchet-type open-end wrench which is inexpensive to manufacture, which is rugged in construction, which is compact in size, and which is very easy to manipulate.

A still further object of the invention is to provide an improved open-end ratchet wrench which involves only a few parts, which has a wide range of adjustment, and which provides a reliable gripping action, while at the same time, being arranged so that it can perform with ratchet action, thereby enabling nuts, boltheads, or similar objects to be rotated by the Wrench in limited space without the necessity of completely disengaging the jaws of the wrench from the object during its rotation.

Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawing, wherein:

FIG. 1 is a top plan view of an improved ratchet wrench constructed in accordance with the present invention.

FIG. 2 is a side elevational view of the ratchet wrench of FIG. 1, shown in locking engagement with a nut.

FIG. 3 is a bottom view of the ratchet wrench of FIGS. 1 and 2.

FIG. 4 is a fragmentary side elevational view of the ratchet wrench of FIGS. 1, 2 and 3, with the handle thereof operated so as to provide a ratchet action, namely, so as to allow the jaws of the wrench to slip around the nut engaged thereby from one set of opposed flat surfaces thereof to the next adjacent set.

Referring to the drawing, 11 generally designates an improved adjustable ratchet wrench constructed in accordance with the present invention. The wrench 11 comprises a main housing portion 12 formed with an upstanding post element 13 and formed below said post ice element with a rectangular aperture 14. Journalled vertically in said aperture, as viewed in FIG. 2, is a knurled Worm member 15, the worm member 15 being rotatablymounted on a shaft element 16 secured in the housing and. extending vertically and substantially centrally through the square aperture 14.

The housing 12 is provided with the rear web portion 17 of reduced thickness terminating in the apertured end lug 18. Designated at 19 is a handle which is formed at its forward end with the recess 20 in which the lug 18 is received, being pivotally-connected to the forward end portion 21 of the handle by a transverse rivet 22. The recess 20 is suitably-shaped so that handle 19 is freely rotatable relative to lug 18.

Designated at 23 is a first wrench jaw which is formed with a vertical key member 24 slidably-engaged in a correspondingly-shaped keyway 25 formed in the housing 12 and extending parallel to the axis of the worm member 15. Thus, as shown in FIG. 2, the main body of the jaw 23 projects forwardly from and is substantially perpendicular to the housing 12, namely, projects perpendicular to the key member 24. Key member 24 is slidably-received inside the post member 13.

Key member 24 is formed with rack teeth 26 which meshingly engage with the worm member 15 so that rotation of the worm member moves the key member 24 in the keyway 25 and correspondingly moves the main jaw body 23.

A second jaw, designated at 27, is pivoted to the reduced portion 17 of housing 12 by a transverse rivet 28 and normally extends substantially parallel to the first jaw 23. The pivoted jaw 27 is provided with an upwardlytapering aperture 29 receiving the post member 13, the aperture 29 being suitably-tapered to allow a definite amount of pivoting of the jaw 27, for example, from the position shown in FIG. 2 to the position shown in FIG. 4, as will be presently described. A flat spring 30 has a main, relatively wide supporting portion engaged in the top end portion of aperture 14 between the top end of worm member 15 and the top wall of the aperture and has a reduced portion 31 extending through a notch 32 to engage against the edge of the inner end portion of pivoted jaw 27.

The relatively wide main body portion of the leaf spring 30 is held in place by the worm shaft 16 which extends through an aperture in the leaf spring, whereby the worm element 15 acts as a holding means to maintain the wide main body of the leaf spring 30 against the top wall of the rectangular notch 14, the transverse inner edge of spring 30 being substantially in abutment with the vertical wall of the aperture 14 at the upper left corner thereof, as viewed in FIG. 2, to prevent the spring from rotating. The projecting portion 31 of the spring is arcuately-bowed and acts against end lug portion 34 of jaw 27 so as to bias jaw 27 in a counterclockwise direction, as viewed in FIG. 2. The spring portion 31 is yieldable, however, whereby the jaw 27 may be, at times, allowed to rotate, for example, from the position of FIG. 2 to the position of FIG. 4 in a manner presently to be described.

The reduced forward end portion 21 of handle 19 is formed with a curved notch 35 generally corresponding in shape to the lug 34 and being adapted to interengage therewith, at times, in the manner illustrated in FIG. 2.

Thus, this relatively close interengagement is obtainable by rotating the handle 19 in a clockwise direction, around the pivotal axis defined by rivet 22. When the handle 19 is rotated in the opposite direction, namely, in a counterclockwise direction, as illustrated in FIG. 4, notch 35 disengages from lug 34 and lever 27 is free to rotate within the limits permitted by engagement of post member 13 in aperture 29 and against the biasing force of the leaf spring element 31.

In operation, assuming that the wrench is to be used to tighten a nut, shown at 40 in FIG. 2, under conditions where only a limited amount of rotary movement of the wrench is permitted, for example, in a relatively constricted space, the jaws 27 and 23 are first engaged on the opposite side faces of the nut 40 in the manner illustrated in FIG. 2, the worm 15 being used to move the lower jaw 23 into engagement with one face of the nut while the opposite jaw 27 is in engagement with an opposite face thereof. Under these conditions, the lug 34 is lockingly-seated in the notch 35. The handle 19 is then rotated in a clockwise direction as far as permitted in the working space. Jaw 27 is rigidly-held parallel to jaw 23 under these conditions because of the locking engagement of lug 34 in recess 35. When the limit of clockwise rotation of the handle 19 is reached, the handle is rotated in a counterclockwise direction, as shown in FIG. 4, whereupon notch 35 disengages from lug 34 allowing the jaws to slip around the nut 40 in a counterclockwise direction, for example, to the position shown in FIG. 4, against the spring force of the fiat spring 31. The counterclockwise rotation of handle 19 may be continued beyond the point shown in FIG. 4 to move the jaws 27 and 23 into engagement with the next adjacent set of opposed flat nut faces. Thereupon, the handle 19 may be rotated in a clockwise direction, pro viding the locked condition of the jaws illustrated in FIG. 2, namely, wherein lug 34 lockingly-seats in notch 35, with spring 31 restored to its normal configuration of FIG. 2. The above-described process may then be repeated.

To reverse the above process, namely, to loosen a nut, or similar object, the position of the wrench is reversed from that illustrated in FIG. 2 and the same procedure as described above is used.

While a specific embodiment of an improved adjustable ratchet wrench has been disclosed in the foregoing description, it will be understood that various modifications within the spirit of the invention may occur to those skilled in the art. Therefore, it is intended that no limitations be placed on the invention except as defined by the scope of the appended claims.

What is claimed is:

1. An adjustable ratchet wrench comprising a main housing formed with an opening, a worm element journaled in said opening, a first movable jaw slidably-engaged in said housing and projecting forwardly therefrom, rack bar means on the first jaw meshingly-engaged with said worm element, whereby said first jaw is slidably-adjusted responsive to rotation of said worm element, a handle pivoted to said housing and extending rearwardly therefrom, a second jaw pivoted to said housing and extending substantially parallel to said first jaw, a rear lug on said second jaw, said handle being formed with a detent notch at its forward end to lockingly-engage said lug when the handle is rotated in one direction relative to the housing and being disengageable from the lug responsive to rotation of the handle in the opposite direction relative to the housing, spring means acting between the housing and the second jaw biasing said lug toward locking engagement with said detent notch, and means limiting rotation of said second jaw relative to the housing, wherein said rotation-limiting means comprises a post element on the housing, said second jaw being formed with an aperture receiving said post element, the aperture being sufficiently large to allow limited rotation of the second jaw relative to the post element, wherein said post element extends parallel to the axis of rotation of the worm element, wherein the rack bar means is slidably-received substantially axially in the post element, wherein said spring means comprises a leaf spring secured to said housing and engaging said lug, and wherein said aperture has end walls flaring in the direction of the first jaw.

2. The adjustable ratchet wrench of claim 1, and wherein said opening is substantially rectangular and said worm element has its ends closely adjacent the opposite walls of said opening, said leaf spring being secured between an end of the worm element and an adjacent wall of said opening.

References Cited UNITED STATES PATENTS 1,183,371 5/1916 Ginsburg 8l-l1l X 1,358,241 11/1920 Parker 81-91 1,929,133 10/1933 Worth 8l1ll X 2,471,537 5/1949 Norman 81-91 OTHELL M. SIMPSON, Primary Examiner

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