US3541899A

US3541899A - Quickly adjustable end wrench

Info

Publication number: US3541899A
Application number: US706357A
Authority: US
Inventors: James H Tanner
Original assignee: KOERPER ENG ASSOCIATES Inc
Current assignee: KOERPER ENG ASSOCIATES Inc
Priority date: 1968-02-19
Filing date: 1968-02-19
Publication date: 1970-11-24
Anticipated expiration: 1987-11-24

Description

Nov. 24, 1970 J. H. TANNER QUICKLY ADJUSTABLE END WRENCH I Filed Feb. 19, 1968 United States Patent 3,541,899 QUICKLY ADJUSTABLE END WRENCH James H. Tanner, Milwaukee, Wis., assignor to Koerper Engineering Associates, Inc., Milwaukee, Wis., a corporation of Wisconsin Filed Feb. 19, 1968, Ser. No. 706,357 Int. Cl. B25b 13/16 US. Cl. 81165 Claims ABSTRACT OF THE DISCLOSURE Adjustment of the movable wrench jaw is effected by means of a slide movable along the handle to rotate a helical shaft that is gear connected with a worm which actuates the jaw. The front end portion of the helical shaft is a reduced diameter journal engaged by a split bearing comprising an inner bearing member and a press fitted complementary outer bearing member. The gear on the helical shaft reacts against the split bearing to take rearward thrust; a thrust washer on the rear of the journal portion takes forward thrust.

This invention relates to adjustable end wrenches and relates more especially to the type of end wrench that has a longitudinally movable slide on its handle which cooperates with a helical shaft to effect rapid adjustment of the movable jaw of the wrench.

The best known type of adjustable end wrench has a worm that is confined to rotation in its head portion with its thread meshingly engaged with a toothed shank on the movable jaw of the wrench. Adjustment of the movable jaw is effected by manipulation of the worm, and is therefore a rather slow and awkward procedure.

The patent literature discloses a number of proposals for facilitating the adjustment of the movable jaw of such a wrench, usually by means of a slide that is constrained to lengthwise motion along the handle of the wrench and which cooperates with a helical shaft that extends lengthwise in the handle and is rotated by the slide as the slide moves back and forth. The helical shaft has a connection with the movable jaw of the wrench whereby adjusting motion is imparted to that jaw in consequence of slide motion. See, for example, Patents Nos. 1,306,020, 2,648,- 244, and 2,795,987.

In spite of the obvious deficiencies of the common worm-actuated wrench and the numerous proposals for end wrenches that can be quickly and easily adjusted, the slide actuated wrench has not met with commercial favor.

A critical examination of the prior suggestions indicates that the reason none of them has been accepted is simply that none of them Would have provided a truly acceptable tool. On many of the prior art wrenches the handle was so Wide and thick as to be clumsy to hold and ethetically unsatisfactory. In most cases the actuating mechanism comprised so many small and complex parts as to make high cost inevitable. Often, too, the mechanism was of such nature as to include parts which were necessarily rather delicate and which therefore could not be expected to have a long useful life; and often this disadvantage was compounded with complicated assembly procedures that not only made for a high initial price but militated against the making of repairs by any but a skilled mechanic.

With these considerations in mind, it is a general object of the present invention to provide a quickly adjustable open end wrench of the type having a slide that is movable longitudinally along its handle for effecting adjusting actuation of its movable jaw, and which wrench is very low in first cost by reason of having few and 3,541,899 Patented Nov. 24, I970 simple parts that can be quickly and easily made and assembled, and is easy to maintain by reason of the fact that its parts are inherently sturdy and its disassembly and reassembly can be accomplished by a person equipped with no more than a screwdriver and a minimum of mechanical skill.

Another and very important general object of this invention is to provide an adjustable wrench of the character described that is well balanced, comfortable and esthetically satisfactory at the same time that it is simple, dependable and inexpensive.

Another and more specific object of this invention is to provide actuating means for a wrench of the character described comprising a unitary helical shaft, a slide, and a very simple, inexpensive and easily assembled means for constraining the helical shaft to rotation.

With these observations and objects in mind, the manner in which the invention achieves its purpose will be appreciated from the following description and the accompanying drawing. This disclosure is intended merely to exemplify the invention. The invention is not limited to the particular structure disclosed, and changes can be made therein which lie within the scope of the appended claims without departing from the invention.

The drawing illustrates one complete example of t e physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

FIG. 1 is a plan view of an adjustable end wrench of this invention with portions broken away;

FIG. 2 is a longitudinal sectional view taken on the plane of the line 22 in FIG. 1;

FIG. 3 is a cross sectional view taken on the plane of the line 3-3 in FIG. 2; and

FIG. 4 is a cross sectional view taken on the plane of the line 44 in FIG. 2.

Referring now to the accompanying drawings, the numeral 5 designates generally the body or frame of the wrench of this invention, which has an elongated handle portion 6 and a wider head portion 7 at the front end of the handle portion. A fixed jaw 8 is formed integrally with the body and projects forwardly from its head portion while a movable jaw 9 is mounted on the head portion for sliding motion toward and from the fixed jaw.

The actuating mechanism for the movable jaw 9 comprises a worm 10 that is confined to rotation in an upwardly opening recess 11 in the head portion with its thread meshingly engaging a toothed shank 12 on the movable jaw that projects into said recess. The actuating mechanism further comprises a helical shaft 13 that extend lengthwise in a longitudinal upwardly opening groove 14 in the handle portion of the body, a slide 15 that is constrained to motion back and forth along the handle and which is so connected with the helical shaft that motion of the slide is translated into rotation of the helical shaft, and a bevel gear 16 fixed on the front end of the shaft and meshing with a pinion 17 coaxially fixed on the worm, for transmitting shaft rotation to the worm.

The body 5 comprises a unitary casting or drop forging having its handle portion 6 formed with a U-shaped cross section that defines the groove 14. The upwardly opening recess 11 in the head portion of the body opens at its rear to the front end of the groove 14 in the handle portion, and it is of sufficient depth so that the worm 10 is entirely received therein. The recess opens to the front of the body and to one side thereof through a slot 19 in which the shank portion 12 of the movable jaw 9 is slidably received.

The worm 10 has its axis oblique to the centerline of the handle portion and parallel to the path of motion of the movable jaw. The pinion 17 is preferably formed integrally with the worm and is at the end of it that is nearer the handle. At its pinion end the worm also has a coaxial and integral conical trunnion portion that is received in a conical well in the head portion. A screw 21 is threaded into a hole in the body that is coaxial with said well, and it has a conical tip that is received in a coaxial well in the other end of the worm to cooperate with the trunnion portion 20 in constraining the Worm to rotation.

The pinion 17 serves as a stop that cooperates with the end tooth on the shank portion 12 of the movable jaw to define the limt of spreading adjustment of that jaw.

The handle portion 6 of the body is reinforced by an elongated plate 22 which is welded to it along most of its length, at opposite sides of the groove 14. The plate 22 has a medial longitudinal slot 23 therein through which the groove 14 opens outwardly, and the marginal edge portions of the plate at each side of its slot 23, which partway overlie the mouth of the groove 14, provide ways 24 upon which the slide 15 is guided for fore-and-aft motion. The slot 23 is widened somewhat at its rear end to provide a bay 25 through which the slide is insertable.

The helical shaft 13 is formed of twisted stock having a rectangular cross section. Near its front end, however, it has a reduced diameter journal portion 26, and its front extremity is peened or swaged to provide a rivet-like head 27 by which the bevel gear 16 is non-rotatably secured on the front end of the journal portion.

The slide 15 is preferably made of nylon or the like. It has an outer ridged or knurled button portion 28 by which it can be manipulated back and forth along the handle and an inner yoke portion 29 that straddles the helical shaft in close sliding engagement with opposite surfaces thereof. A narrow neck portion 30 connects the button and yoke portions of the slide and cooperates with them in defining opposite grooves in which are received the ways 24 that comprise portions of the plate 22.

The helical shaft is rotatably journaled in a split hearing that comprises an inner bearing member 31 and an outer bearing member 32, both received in the rear portion of the recess 11 in the body. Both bearing members are made of molded nylon or a similar material that provides a self-lubricating bearing surface and is substantially hard but somewhat resilient. Each of the bearing members has a longitudinal groove of semicircular cross section, and the bearing members are assembled with these grooves opening toward one another to receive the journal portion 26 of the helical shaft. The two bearing members have coplanar front faces 33 and 34 and coplanar rear faces 35 and 36, said faces being normal to the shaft axis.

The inner bearing member 31 fits closely, but not necessarily tightly, in the bottom of the recess 11. The outer bearing member 32, however, is confined in the recess under lateral compression by means of a pair of tangs 37 which are integral with the body and which project into the recess from the side surfaces thereof. As the outer bearing member is forced downwardly into the recess, the tangs 37 bite into its side surfaces so that it is compressively confined against outward displacement by the tangs and is also held by them against fore-and-aft displacement.

The rear face of the bevel gear 16 directly abuts the coplanar front faces 33 and 34 of the two bearing members and thus cooperates with the bearing members to prevent rearward displacement of the shaft. A thrust washer 38 is confined between the helical portion of the shaft and the coplanar rear faces 35 and 36 of the two bearing mem bers to prevent forward displacement of the shaft. The inner bearing member 31 is of course con-fined against foreand-aft displacement by means of the bevel gear 16 and thrust washer 38, which respectively maintain its front face 34 and rear face 36 coplanar with the front and rear faces of the outer bearing member.

Inasmuch as the helical shaft 13 is supported only by the bearing members, and these are located rearwardly adjacent to the meshing bevel gear and pinon, no problems of shaft and bearing alignment are presented by the actuating mechanism in the wrench of this invention.

In assembling the wrench, the plate 22 is welded to the body and the helical shaft unit is separately assembled, the thrust washer 38 being first slipped onto its journal portion 26 and the bevel gear 16 then being secured to the front of the shaft by peening its end portion to form the head 27. The movable jaw 9 is slid into its slot 19 in the body, the worm 10 is inserted into the recess 11, and the screw 21 is engaged with the worm to hold the worm in place. The pinion 17 on the worm holds the movable jaw 9 against displacement off of the body, as pointed out above. The movable jaw is set in its widest open position of adjustment for the next assembly step.

The inner bearing member 31 is inserted into the recess 11, and the slide 15 is inserted into the bay 25 in the plate 22 and moved a little distance forward into the groove 23 proper. The helical shaft 13 is then inserted through the slot 23 in the plate and is engaged one turn with the slide, after which the bevel gear :16 is brought into meshing engagement with the pinion 17, establishing the journal portion 26 of the shaft in the longitudinal groove in the inner bearing member. The outer bearing member 32 is then pressed into place between the tangs 37.

Preferably a cover plate 39 closes the recess 11 to keep dirt and the like out of the bearing members, worm, pinion and bevel gear. The cover plate can fit into a shallow depression 40 in the top surface of the head portion of the body that is shaped to fit it, so that its outer surface is substantially flush with the top surface of the plate 22. Bosses 41 project from the inner surface of the cover plate through closely fitting holes in the body, and the cover plate is detachably secured to the body by means of screws 42 that are threaded into these bosses and have their heads engaging the bottom surface of the body.

To disassemble the wrench for repairs, it is only necessary to remove the cover plate and pry out the outer bearing member with a screwdriver or the like, after which the actuating mechanism is readily removable.

From the foregoing description taken with the accompanying drawing it will be apparent that this invention provides an adjustable end wrench of the type that can be quickly and easily adjusted by means of a slide that is movable lengthwise along its handle, which wrench is attractive, inexpensive and sturdy, comprises a few simple and easily made parts that can be quickly assembled by relatively unskilled labor, and can be completely disassembled for repair.

What is claimed as my invention is:

1. In an adjustable end wrench of the type comprising a body having a head portion on which there is a. relatively fixed jaw and in which there is a recess that opens to the top of the body and having a handle portion projecting rearwardly from the head portion and in which there is a lengthwise extending upwardly opening groove that communicates at its front end with said recess, a movable jaw slidably mounted on said head portion and having a toothed shank in said recess, a worm in said recess constrained to rotation with its thread meshing with the toothed shank and on which a pinion is coaxially fixed, a shaft in said groove having a helical portion, a slide constrained to motion longitudinally of the handle portion and having a part engaging the helical portion of the shaft for translating slide motion into shaft rotation, and a gear coaxially connected with the shaft at its front end and meshing with said pinion, said wrench being characterized by:

(A) the shaft having a coaxial journal portion at its front, rearwardly adjacent to the gear and of smaller diameter than the gear;

(B) an axial thrust bearing element on the shaft at the rear of the journal portion;

(C) inner and outer bearing members in said recess in the body, each having a semicircular groove in which the journal portion of the shaft is received, and which cooperate to define a bearing therefor, the bearing members being of a self-lubricating, substantially hard but resilient material and the inner bearing member being in the bottom portion of said recess and having a substantially loose fit therein;

(D) a pair of opposite tangs on the body which project into said recess and bite into opposite sides of the outer bearing member to compressively confine it against outward displacement and hold it against fore-and-aft displacement, and such confinement of the outer bearing member confining the inner bearing member against outward displacement; and

(B) said inner and outer bearing members having coplanar front and rear surfaces which are respectively engaged by the rear face of the gear and the front face of said thrust bearing element to preclude axial displacement of the shaft and confine the inner bearing member against axial displacement.

2. The adjustable end wrench of claim 1 further characterized by:

(A) said journal portion of the shaft being of smaller diameter than the helical portion of the shaft rear- Wardly adjacent thereto; and

(B) said axial thrust bearing element comprising a washer confined between the rear faces of the bearing members and the front end of the helical portion of the shaft.

3. The adjustable end wrench of claim 1 further characterized by:

(A) the handle portion of said body being substan- 6 tially U-shaped in cross-section to define said groove; and

(B) a plate extending lengthwise along the handle portion of the body and secured thereto along opposite sides of said groove,

(1) said plate having a lengthwise extending slot which is narrower than said groove,

(2) the portions of said plate which project inwardly across the mouth of said groove providing ways for the slide, and

(3) the slot in the plate having an enlarged rear end portion through which the slide is insertable for engagement with said ways.

4. The adjustable end wrench of claim 3 further characterized by:

a cover plate removably secured to the head portion of the body and closing asid recess.

5. The adjustable end wrench of claim 1 wherein the helical portion of said shaft and the journal portion thereof are integral parts of a unitary shaft element, further characterized by:

said gear being secured to the shaft by means of a swaged-over front end portion of the shaft element.

References Cited UNITED STATES PATENTS 3,125,911 3/1964 Schlote 81-172 X 2,795,987 6/1957 Schlote 81-165 2,753,748 7/1956 Schlote 81165 1,664,880 4/1928 Flintermann 308 X 278,404 5/1883 Crowell 30858 X JAMES L. JONES, JR., Primary Examiner