Abstract:
A ratcheting device comprising a driver head assembly which includes at least two 3-D sprag elements positioned within a first groove within the driver head assembly such that at least one of the 3-D sprag elements may lockingly engage the driver head assembly and a mating hub assembly to allow for rotation of the hub assembly in one direction with respect to the driver head assembly. This arrangement allows the ratcheting tool to impart torque in either the clockwise or counterclockwise direction without having to first rotate the ratcheting tool in the direction opposite the direction in which the torque is applied. This arrangement also allows the ratcheting tool to impart torque in either the clockwise or counterclockwise direction while in the neutral position.

Description:
CROSS REFERENCE TO RELATED PATENTS 
     This invention relates to an invention disclosed in U.S. Pat. No. 5,482,144, which is assigned to the assignee of this application. The present application incorporates this patent by reference. 
    
    
     ORIGIN OF THE INVENTION 
     The invention described herein was made by employees of the United States Government, and may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon or therefor. 
    
    
     TECHNICAL FIELD 
     The present invention relates generally to hand tools and more particularly to ratcheting devices which may be used in one-way and two-way socket wrenches. 
     BACKGROUND ART 
     Socket wrenches generally are old and well known for use in any application which requires the loosening or tightening of nuts, bolts and other fastening devices. Socket wrenches typically include some sort of locking mechanism which will allow free motion in one direction while preventing motion in the opposite direction. The prior art locking mechanisms typically include ratcheting devices which are limited by the pitch and spacing of the teeth of the ratcheting wheel or bar. Such a limitation induces a minimum motion requirement in the direction opposite the desired loosening or tightening to move the engaging pawl, click or detent to the next tooth before one is able to impart the torque required to perform the desire loosening or tightening function. If the loosening or tightening function is performed in an area where space is extremely limited then it becomes very difficult to perform such functions because the pitch and spacing of the teeth on the ratcheting wheel or bar would require a minimum amount of movement in the opposite direction before torque is transferred to the object which one desires to loosen or tighten. Further, the prior art socket wrenches are not capable of allowing one to transfer torque in both the clockwise and counterclockwise directions without having to make adjustments to the socket wrench. Thus, one would then have the capability of performing bi-directional fine adjustments during the tightening or loosening function. 
     STATEMENT OF THE INVENTION 
     Accordingly it is an object of this invention to provide a new and improved ratcheting device. 
     It is another object of the present invention to provide an improved ratcheting device which may be used in a hand tool. 
     It is a further object of the present invention to provide an improved ratcheting device which does not require a minimum movement in the opposite direction before torque can be imparted in the desired 
     It is yet a further object of the present invention to provide an improved ratcheting device which will allow one to impart torque in both the clockwise and counterclockwise directions. 
     It is still a further object of this invention to provide an improved ratcheting device which includes a neutral setting. 
     The above and other objects of the present invention are achieved by providing a ratcheting tool comprising a driver head which includes at least two 3-D sprag elements positioned within a first groove within the driver head such that one of the sprag elements may lockingly engage the first groove of the drive head when the driver head is rotated. The ratcheting tool also includes a neck which is integrally formed with the driver head. The ratcheting tool further includes a handle which is integrally formed with the neck such that the handle may cause the driver head to rotate in a clockwise or counterclockwise direction. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a full view of the present invention. 
     FIG. 2 is a sectional view of the present invention taken along lines A—A of FIG.  1 . 
     FIG. 3 is a sectional view of the present invention taken along lines B—B of FIG.  2 . 
     FIG. 4 is a view of the hub assembly of the present invention. 
     FIG. 5A shows the 3-D sprag elements of the present invention. 
     FIG. 5B shows a side view of FIG. 5A 
     FIG. 6 shows the inside view of the back cover of the present invention. 
     FIG. 7 shows the inside view of the driver head of the present invention. 
     FIG. 8A shows a first alternate embodiment of the present invention. 
     FIG. 8B shows a side view of FIG.  8 A. 
     FIG. 9A shows a second alternate embodiment of the present invention. 
     FIG. 9B shows a side view of FIG. 9A of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to FIGS. 1 and 2 wherein like reference numerals refer to like elements throughout. Referring now to FIG. 1, a ratchet tool generally shown as  10  includes a driver head  12  a neck  30  and a handle  40 . Referring now to FIG. 2, a sectional view of FIG. 1 of the present invention taken along lines A—A, shows a ratchet tool  10  of the present invention wherein the ratchet tool  10  includes driver head  12  which further includes a first groove  16  within bore  14  and a second groove  36   a  which is located within second bore  36   b  of driver head  12 . First groove  16  is machined such that it receives beveled surfaces  20   a  of sprag element  20  in a locking engagement. Second bore  36   b  is machined such that it may receive cover  32 . Beveled surfaces  20   b  are received by groove  24  of hub assembly  22 . Hub assembly  22  is concentrically positioned within driver head  12  and sprag elements  20  are radially positioned with respect to hub assembly  22  within groove  24 . Ratchet tool  10  further includes dowel pins  29  which terminate in bore  29   a  (not shown) of cover  32  (see FIG.  6 ). Dowel pins  29  are secured (by conventional means) within bore  29   a  (not shown) of cover  32 . When cover  32  is made to rotate with respect to driver head  12 , dowel pins  29  cause sprag elements  20  which are spaced 180 degrees apart to pivot about their respective dowel pins  28 . Dowel pins  28  pass freely through bores  28   a  of sprag elements  20  and terminate in driver head  12  of ratchet tool  10  so as to allow the pivoting motion of sprag elements  20 . If ratchet tool  10  were to only include two (2) sprag elements  20  then only one dowel pin  29  would be necessary to facilitate the relative rotation of hub assembly  22  in the clockwise and counterclockwise direction. Snap ring  34  is received by groove  34   a  of hub assembly  22  to rotatably hold hub assembly  22  within bore  14  of driver head  12 . Snap ring  36  is received by second groove  36   a  of driver head  12  to rotatably hold cover  32  within bore  36   b.  Dowel pins  28  are securely positioned (by conventional means) within driver head  12  of ratchet tool  10 . This arrangement allows sprag elements  20  to be slightly rotated within groove  16 . A slight rotation in the clockwise direction will prevent rotation of hub assembly  22  in the clockwise direction with respect to driver head  12 . A slight rotation in the counterclockwise direction will prevent rotation of hub assembly  22  in the counterclockwise direction. When the dowel pins  28  do not cause a slight rotation in either direction then hub assembly  22  will not rotate in either direction with respect to driver head  12 . This is the neutral position. While in the neutral position, driver head  12  may impart torque on a fastening element (not shown) in either the clockwise or counterclockwise directions. 
     Referring now to FIG. 3, a sectional view of FIG. 2 along lines B—B, driver head  12  and hub assembly  22  are shown with sprag elements  20  positioned radially between driver head  12  and hub assembly  22 . Preload spring element  38  passes through bore  38   a  of sprag elements  20 . The preload springs applies a force to sprag means such that sprag means  20  are slightly biased toward and within groove  24  of hub assembly  22 . Preload spring element  38  keeps sprag means  20  in contact with grooves  24  so that hub assembly  22  may rotate freely in one direction while immediately locking if rotation is attempted in the opposite direction. FIG. 3 further shows bore  39  which receives ball bearing (not shown) so as to lock driver head  12  in either the clockwise, counterclockwise or neutral settings. 
     Referring now to FIG. 4, hub assembly  22  includes groove  24  which is machined to receive beveled surfaces  20   a  and  20   b  of sprag elements  20  in locking engagement fashion when driver head  12  is rotated relative to hub assembly  22 . Groove  34   a  is used to rotatably secure hub assembly  22  with respect to driver head  12 . This is achieved via snap ring  34  (see FIG. 2) which snugly fits in groove  34   a  and abuts against surface  15  within driver head  12 . Hub assembly  22  further includes a male element  26  designed to mate with a socket element (not shown) for tightening or loosening any fastening element (not shown). Male element  26  includes a surface/stop  27  which is slightly raised with respect to surface  12   a  of driver head  12 . 
     Referring now to FIGS. 5A and 5B, sprag element  20  is shown with greater detail. On the face  20   c  of each sprag element  20  the beveled surfaces  20   a  and  20   b  have bevel arcs which have off-setting centers. Beveled surfaces which are located at a common end of sprag means  20  include bevel arcs with centers which are not off-setting. Thus, bevel arcs which are located at opposite ends of sprag elements  20  have off-setting centers. It is the off-setting centers of these beveled surfaces which allows hub assembly  22  to rotate in one direction with respect to driver head  12  while remaining fixed in the other direction with respect to driver head  12 . A slight rotation or pivot of sprag element  20  will allow for rotation of hub assembly  22  in the opposite direction. When there is no rotation or pivot of sprag element  20  then hub assembly  22  will remain locked for rotations in the clockwise and counterclockwise directions thus allowing ratchet tool  10  to transfer torque in either the clockwise or counterclockwise direction. Conventional means (not shown) may be employed such that cover  32  may easily facilitate the selection of direction of rotation of hub assembly  22  with respect to driver head  12 . Thus by selectively slightly rotating or pivoting sprag elements  20  which are spaced 180 degrees apart hub assembly  22  will be allowed to rotate with respect to driver head  12  thereby allowing ratchet tool  10  to impart torque in the direction opposite the slight rotation or pivot. In the preferred embodiment ratchet tool  10  may be allowed to impart torque in the clockwise direction or the counterclockwise direction or in both directions. 
     Referring now to FIG. 6, cover  32  includes surface  32   a  wherein detents  33 ,  35  and  37  are shown. The purpose of the cover is to enclose the mechanism and provide the means for controlling the direction (clockwise or counterclockwise) of torque applied by ratchet tool  10 . Detents  33 ,  35  and  37  are provided for a roller bearing (not shown) to lock ratchet tool  10  in either the clockwise, counterclockwise or neutral settings. The roller bearing fits within bore  39  (see FIGS. 3 and 7) of driver head  12 . This arrangement is common among socket wrenches for setting and locking the wrench at a desired setting. Cover  32  further includes dowel pins  29  (see FIG. 2) which pivot sprag means  20  to achieve the desired setting (clockwise, counterclockwise or neutral) when cover  32  is rotated. Cover  32  includes bores  29   a  (not shown) which securely hold dowel pins  29 . Dowel pins  29  are located such that a rotation of the cover causes the pins to push against a pair of similarly oriented sprags, compressing preload spring elements  38  thereby disengaging that pair of sprags thus allowing for rotation in one direction and locking in the opposite direction. 
     Referring now to FIGS. 2 and 7, driver head  12  includes groove  16  for receiving sprag element  20  and groove  36   a  for receiving snap ring  36 . Driver head  12  further includes bore  39  for receiving ball bearing (not shown) for locking and setting ratchet tool  10  in either the clockwise, counterclockwise or neutral positions. 
     Referring now to FIGS. 8A and 8B, a two-way ratchet tool with free running neutral position consists of essentially the same components as the two-way ratchet with a locking neutral position. For the free-running neutral position, a pair of springs  380   a  and  380   b  is used on each sprag means  200 . Spring  380   a  provides a preload to sprag means  200  while spring  380   b,  the positioning spring, is attached to the cover and serves the same purpose as dowel pins  29  of the preferred embodiment. In the neutral position, the force of positioning spring  380   b  overpowers the force of preload spring  380   a  and thereby disengages sprag means  200 . Rotating the cover so that the positioning spring further compresses causes it to continue to hold the sprag in the disengaged position. Rotating the cover in the opposite direction such that positioning spring  380   b  extends allows the force of preload spring  380   a  to overpower the force of positioning spring  380   b  and thus engages the sprag. Therefore, this arrangement allows for rotation only in one direction and locking only in one direction. 
     Referring now to FIGS. 9A and 9B, in a linear ratchet device, the mechanism would consist of two rails  120  and  220  sprag element  200 , preload spring  380   a  and positioning spring  380   b.  This arrangement is analogous to that shown in FIGS. 8A and 8B in that the device allows for movement in one direction only and locking in one direction only.