05/490080

09/30/1975

07/19/1974

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Palmer Filter Equipment Co. (Fairview, PA)

192/44

81/59.100, 81/63.100

B25B13/46; F16D41/08; B25B13/00; F16D41/00

192/44,72 81/59.1,63.1

Herrmann, Allan D.

STATEMENT OF INVENTION

This invention relates to clutches and, more particularly, to a specific type of clutches for wrenches.

OBJECTS OF THE INVENTION

It is an object of the invention to provide an improved clutch.

Another object of the invention is to provide an improved wrench handle .

Another object is to provide a one-way clutch that is simple in construction, economical to manufacture, and simple and efficient to use.

With the above and other objects in view, the present invention consists of the combination and arrangement of parts hereinafter more fully described, illustrated in the accompanying drawings and more particularly pointed out in the appended claims, it being understood that changes may be made in the form, size, proportions, and minor details of construction without departing from the spirit or sacrificing any of the advantages of the invention.

REFERENCE TO PRIOR ART

This invention is an improvement over U.S. Pat. Nos. 2,707,540 and 3,019,872 to Harry C. Morris.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a preferred embodiment of the invention, showing the clutch used in a wrench , the clutch being disengaged .

FIG. 2 is a cross sectional view taken on line 2--2 of FIG. 1 , but with the cap of the wrench turned to engage the clutch .

FIG. 3 is a cross sectional view taken on line 3--3 of FIG. 1.

FIG. 4 is a top view of FIG. 5 , and as indicated by line 4--4 of FIG. 3 shows the underside of the cap and star wheel of the wrench .

FIG. 5 is a partial cross sectional view taken on line 5--5 of FIG. 4 and showing the cap and star wheel inverted with respect to FIGS. 2 and 3 .

FIG. 6 is a partial cross sectional view taken on line 6--6 of FIG. 4.

FIG. 7 is a cross sectional view taken on top view of the wrench with the cap, locking balls and button removed, and with the star wheel and clutch actuating spring partly broken away, showing the clutch shoes and rollers at the level indicated by line 7--7 of FIG. 3.

FIG. 8 is a bottom top view of the shank shown in FIG. 9.

FIG. 9 is a side view of the shank as shown in FIG. 8.

FIG. 10 is an enlarged a perspective view of the a press-in washer and that forms part of the cap, and of the clutch actuating spring ring , inverted with respect to FIGS. 2 and 3 .

DETAILED DESCRIPTION OF THE DRAWINGS

The clutch according to the invention is shown in a preferred embodiment in use in a ratchet type wrench for use by mechanics. The wrench is indicated generally at 10, having a drive means by way of a handle 12 , and is made up of the major components , which include the shank 18, cap 27, reversing star wheel 28, shoes 16, cam roller members 19, and clutch actuating spring 31. The wrench body 14 which has an internal cylindrical surface 15 which can be frictionally engage engaged by the outer cylindrical surface surfaces of shoes 16. The body 14 has an internal peripheral groove 37, which receives a spring washer 40 47 . The spring washer 40 47 engages the rim 38 on the shank and holds the shank 18 in place in the body. The shank rests against the shoulders shoulder 11 in the body and freely rotates can rotate between the shoulders shoulder 11 and the washer 47. The corners 56 of the shank, between the cam surfaces 20, are rounded on a radius slightly less than the inside diameter of the shoes 17, so that the shank can rotate relative to the arcuate shoes .

The shank 18 has the .[♂]. socket wrench receiving male member 41, which may be inserted into a suitable socket wrench of a type familiar to those skilled in the art, and a detent ball 42 in hole 71 in the male member urged outward by spring 43 will hold the socket in place. Spring 43 abuts against shoulder 70 in male member 41.

The shank 18 has a round stem 21 that is in the form of a cylinder integrally attached to integral with the cam portion 56 of shank 18. The cam portion 56 is generally square and has the flat cam surfaces 20 on each of its four sides, and these cam surfaces 20 can engage the rollers 19 which in turn can engage the ends 17 of shoes 16 and urge the shoes outward into engagement with surface 15.

The wrench is assembled by placing the shank 18 into the drum body 14 with the rim 38 resting in the counterbore against the shoulder 11 as shown in FIGS. 3 and 4. The snap spring washer 47 is then snapped into the groove 37 so that the shank can freely rotate between the counterbore shoulder 11 and the washer. The shoes 16 are then placed inside the cylindrical surface 15 resting on surface 39 of the shank, and the cams cam roller members 19 are placed between the inclined bevelled ends 17 of the shoes. The star wheel 28 is then laid over top of the shoes 16 and the cam roller members 19 in the position shown in the upper end part of FIG. 7 with the points 29 of the star wheel disposed between the ends 17 of the shoes and overlying the cam roller members 19. It will be noted that the shoes have an arcuate offset 49 cut in them which to receive the outer curved periphery of the star wheel. The star wheel has the upwardly extending lugs 30, within the circular locus of which receive the spring 31 is disposed and locate it in position.].. It will be noted that spring 31 is in the form of a circle ring or annulus with the spaced apart, outwardly extending ends 32. The outwardly extending ends 32 overlie the outer ends of turn outwardly between a pair of the lugs 30 and are received in groove opening 52 in flange 53 of washer 51 which is pressed into a groove 54 at the underside of the cap and forms a rigid part of the cap 27. The ring-shaped spring 21, caged within lugs 30, is also housed in an annular recess at the underside of cap 27, above star wheel 28 as viewed in FIGS. 3 and 4. The A spring washer 23 is disposed in snapped into a groove 60 in shank 18. This washer 23 overlies the well bottom 61 of cap 27 and holds the cap 27 in place. The cap 27 has a groove cut in the underside of it which receives pressed-in washer 51 and the ends 32 of the spring are received in the groove 52 in upturned flange 53 of washer 51.

The groove 33 limits ends of the opening 52 limit the movement of the ends 32 of the annular spring 31 and forces force the spring to rotate together with the cap when the cap is rotated. When the cap is rotated, one end of the opening 52 engages and moves a first end 32 of the spring 31, and the other end 32 of the spring is pressed against an upturned lug 30 of the star wheel 28. When the cap is rotated in the opposite direction, the other end of the opening 52 engages said other end 32 of the spring and the first end of the spring is pressed against a star wheel lug 30. Thus, the star wheel 28 is forced to rotate with the cap by the ends 32 of the spring which engage the lugs 30.

The button 25 is received in a central bore 55 in stem 21 at the end 44 of the shank 18. The corners adjacent the cams 20 are rounded off at 56 on the radius slightly less than the inside diameter of the shoes 17, so that the shank may rotate freely inside the shoes. A spring 24 is supported inside the bore 57 in the button 25, and this spring urges the button outward.

The stem 21 has a radial hole 33 in it, in which the locking balls 26 are received. These locking balls 26 may move into the large peripheral recess 34 in the button 25 when the button is in the depressed position, that is, pushed downward, and when the button 25 is moved held upward by spring 24, the locking balls 26 are received in the shallow peripheral recess 35 in the button 25 .

The hole A central bore 59 in the cap 27 , coaxial with the shank 18, receives the shank stem 21, and the stem 21 has a peripheral groove 60 which receives the spring washer 23 which rests against the shoulder 61 in the cap and holds the cap on the shank surface of bore 59 has a first pair of diametrically opposed grooves or recesses 62 and a second pair of diametrically opposed grooves or recesses 63. The locking balls 26 may move into either of the two circumferentially spaced pairs of grooves 62 or 63, depending on the position to which the cap 27 is rotated relative to the shank. Thus, when the cap is rotated with the button 25 in the depressed position and the balls 26 in the deep peripheral recess 34 of the button so that a ball 26 is lined up the stem recesses 33 containing the balls 26 can be aligned with one of the pairs of recesses or grooves 62 or 63, the ball balls may move outward and allow the button 25 to jump up urged by the spring 24 so that the ball rests balls rest in the shallow groove 35, as shown in FIG. 2. Thus, the cap 27 will be restrained to rotate with fixed to the shank 18 , and the spring 31 will be forced to rotate with the shank since its ends are received in the groove 51 .

OPERATION OF THE PREFERRED EMBODIMENT

Assume that the button 25 has been depressed, the positioning balls 35 are in the large button recess 34 so that the cap is not fixed to the shank 18, and the cap is turned to a position where the balls 35 are midway between grooves 62, 63 in the cap. The button cannot pop up because the balls 35 cannot move radially out of the large button recess 34. The ring-like spring 32, which is housed in and rotatable with the cap, is in a neutral position as shown in FIG. 7, as is the star wheel 28 whose points 29 are between successive clutch shoes 16. The rollers 19 are also in neutral positions between the clutch shoes.

Now suppose that the cap is rotated counterclockwise as viewed from the top while the shank 18 is held manually or otherwise against rotation. As viewed in FIG. 7, the right hand end 32 of spring 31 is pushed counterclockwise by the adjacent end of opening 52 in flange 53 of washer 51 of the cap, causing the left hand end 32 of the spring to push counterclockwise the adjacent upstanding lug 30 of star wheel 28. Star wheel 28 is thus resiliently pressed to rotate counterclockwise, and its points 29 engage ends of the shoes 16, shifting the shoes counterclockwise until the opposite bevelled ends 17 of the shoes press the rollers 19 against the cam surfaces 20 of the shank 18. Spring 21 is compressed until the locking balls 26 come opposite grooves 63, when the button spring 24 presses the button up and forces the balls 26 into the cap recesses 63 aligned with the stem recesses 33, fixing the cap to the shank in a first setting. If the wrench handle 12 and body 14 are now turned counterclockwise, the shoes 16 are pressed by the rollers against the inner annular surface 15 of the body 14, and the rollers engaging the shank force the shank to rotate with the body, without any play. However, if the wrench handle and body are turned clockwise the shoes are not jammed against the inner annular surface 15 of the wrench body. Since the points 29 of the star wheel engage the ends of the shoe, the shoes will be moved by the shank and The shoes can slide around inside the drum freely wrench body as the handle is rotated in this particular clockwise direction, and thus the clutch operates only one way.

When Conversely, when the cap is rotated clockwise from the neutral position so that the ball 26 moves balls 26 move into the groove 63 grooves 62 the cap will be fixed to the shank in a second setting, the ends left hand end 32 of the spring will engage the opposite other end of the slot opening 52 in the washer 51 of the cap, the right hand end of the spring will push the star wheel clockwise, and the points 29 of the star wheel hold the shoes 16 clockwise relative to the position illustrated in FIG. 7, with rollers 17 jammed between the bevelled shoe ends and the shank cam surfaces 20, so that with clockwise movement of the wrench body the shank must turn, whereas the shank is not forced to turn when the handle is rotated in the other , i.e. counterclockwise, direction relative to the shank. When the handle is rotated opposite to the direction that the end 32 engaged the end defining groove 52 of the washer 51, the cam surface 20 will force cam roller members 19 outward so that they drive the shoes 16 into engagement with the surfaces 15.

The drive washer 64 is pressed into the cap 27 and forms a convenient bearing therein for spring 31.

The star wheel 28 constitutes a single rigid member for positioning all the clutch shoes 16 by engagement therewith when actuated by the cap 27 and the annular spring 31. Reversing of the star wheel reverses the direction in which the shank 18 can be driven. The cap 27 constitutes a rigid actuating member which, by engagement with the actuating spring 31, actuates the reversing member 28 and thus the clutch.

The positioning button 25 does not protrude from the cap 27, even in its outward or raised position, so that it is sheltered against being accidentally depressed.

The foregoing specification sets forth the invention in its preferred practical forms but the structure shown is capable of modification within a range of equivalents without departing from the invention which is to be understood is broadly novel as is commensurate with the appended claims.