Abstract:
An improved dual action indexable wrench having a moment arm connected to a wrench body which can be operated in a first configuration to apply force directly and in a second configuration to apply force by reciprocal motion, which can be readily switched between the two configurations by engaging and disengaging a shoulder on the wrench body having a v-shaped notch and a corresponding leading edge on the handle having square corners dimensioned to be received within the notch on the shoulder.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to indexable wrenches to which other tools such socket heads, crowfoot-type wrenches and the likes are connected for use to install and tighten nuts, bolts and other threaded means, and to break loose the same. 
     More particularly, this invention relates to an improved indexable dual action wrench which can be used in a first variably angled configuration to transmit force applied to a moment arm. In a second configuration, the moment arm can be moved to reciprocate and rapidly rotate the attachment mechanism relative to the moment arm. 
     2. Discussion of the Prior Art 
     Indexable dual action wrenches like the one set forth in U.S. Pat. No. 4,406,186 to the present inventor, Stephen A. Gummow, apply direct torque to a socket head in a first configuration to tighten or loosen a nut and in a second configuration, to rapidly rotate the socket head to spin the nut. That wrench provides more than one position for the handle relative to the wrench body. 
     In U.S. Pat. No. 5,419,221 to James E. Cole, another indexable head ratchet wrench is disclosed. That device describes a dual action wrench which, in its locked position, utilizes a half-splined connecting pin to engage complimentary splines on the inner surface of an orifice in the wrench body as a means to prevent rotation about the axis of the pin. One of the major drawbacks of this deslon is the susceptibility of the splines on the inner surface of the orifice to chipping., burring and breaking. Additionally, in order to permit the handle to move between the locked and unlocked positions, it is necessary for the orifice in the handle to be substantially larger that the “unsplined” portion of the pin which it engages in the unlocked position, resulting with sloppiness in the movement of the handle when in the unlocked position. It is therefore an object of the present invention to provide an improved dual action wrench which operates in a locked configuration and an unlocked configuration, in which the device can be readily switched between the two configurations. 
     It is a further object of the present invention to provide an improved dual action wrench which is switchable between the locked and unlocked configurations, which may be readily positioned in a limited number of different angles in the locked configuration, the positions corresponding to 45° increments. 
     A still further object of the present invention is to provide an improved dual action wrench which is movable between a locked or direct torque configuration and an unlocked or reciprocal configuration, in which the difficulties and drawbacks of prior devices are avoided, including those associated with reliance on mating splines to lock and unlock the wrench. 
     Other objects and advantages of the inventions will appear hereinafter. 
     SUMMARY OF THE INVENTION 
     A ratchet wrench including a preferred embodiment of the invention comprises a ratchet head, a connecting pin, and a handle. The ratchet head includes a conventional ratchet system for rotating a shank about an axis. A conventional socket or an open-end or closed-end crowfoot-type wrench can be connected to a shank. 
     The generally cylindrical connecting pin aligned along an axis parallel to the shank axis and attached to the ratchet head. The connecting pin extends through an orifice in the handle, thereby connecting the handle to the ratchet head. A shoulder of the ratchet head includes a v-shaped notch that is adapted to receive the corner of the handle in a complementary manner to prevent rotation of the handle about the connecting pin axis: and an indented portion of the connecting pin is adapted to allow the handle to rotate freely about the connecting pin axis. 
     The handle is slidable between a locked position and a unlocked position on the connecting pin. In the locked position the handle orifice is disposed about the connecting pin. The handle corner engages the v-shaped notch and the ratchet wrench can be used to rotate a nut or bolt head in a conventional manner. In the unlocked position, the handle orifice is disposed about the indented portion of the connecting pin and the ratchet head can rotate in a full circle about the connecting pin axis. This allows the ratchet wrench to be used to rapidly rotate a nut by moving the handle in a reciprocating manner. 
     When a nut or bolt head to be rotated by the ratchet wrench is near an obstruction, the handle can be unlocked, rotated about the connecting pin axis, then locked, thereby adjusting the angle between the longitudinal axis of the handle and the longitudinal axis of the ratchet head. In many instances, such angular adjustment allows the ratchet wrench to be used to rotate the nut or bolthead the conventional manner while avoiding contact between the handle and the obstruction. 
     In other embodiments of the invention, the improved dual action ratchet device of the present invention is employed in breaker bars and combination wrenches. In these applications, as in the socket wrench embodiment discussed above, the ratchet device is designed to be used in a first locked, variably angled configuration to transmit force applied to a moment arm to directly tighten or loosen threaded means and in a second unlocked configuration to reciprocate the moment arm and thereby rapidly rotate the threaded means. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The features of the present invention, together with further objects and advantages thereof. may best be understood by reference to the following description taken in connection with the accompanying drawings on which: 
     FIG. 1 is a perspective view of the dual action wrench in accordance with the present invention, in such tile wrench handle is in a first and locked position with respect to the wrench body having a conventional ratchet mechanism and a shank to drive a socket head; 
     FIG. 2 is a fragmentary top view of the wrench of FIG. 1 with the wrench handle locked in an angled position with respect to the wrench body in solid lines, and in phantom lines, the other four positions clear of the wrench body to permit the body and handle to pivot in a semi-circle, in 45° increments about a pivot pin mounted in the wrench body; 
     FIG. 3 is a fragmentary perspective view of the wrench of FIG. 1 showing the handle in one of its locked positions with the v-shaped notch in the wrench body; 
     FIG. 4 is an side elevation view wherein the handle is depicted in solid line in a locked position and the handle is depicted in phantom line in an unlocked position. 
     FIG.  5 . is a fragmentary elevation view of a portion of the wrench of FIGS. 1-5 showing chamfers which guide the wrench handle and the wrench body into mating engagement when the wrench handle is locked into position as in FIG. 1; 
     FIG. 6 is a fragmentary elevation view of a portion of the wrench of FIGS. 1-5 showing chamfers which engage the spring loaded detent ball in pivot pin of the wrench; 
     FIG. 7 is a partial perspective view of a second embodiment of a wrench in accordance with the present invention in which the wrench handle is locked in position with respect to a wrench body having a conventional breaker bar mechanism; 
     FIG. 8 is a partial top view of the wrench of FIG. 7; 
     FIG. 9 is a partial perspective view of a third embodiment of a wrench in accordance with the present invention, in which the wrench handle is locked in position with respect to a wrench body having a conventional 6 point hex boxed end; and 
     FIG. 10 is a side elevation view of the wrench of FIG.  9 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In the preferred embodiment of the invention, as illustrated in FIGS. 1-6, a wrench  10  is shown including a wrench body  12 , a wrench handle  14 , and a shank  16  extending downwardly from the center of wrench body  12 . The wrench is provided with a conventional ratchet mechanism (not shown), including a direction selector  18  which can be moved between positions “on” and “off” to cause the shank  16  to spin or drive a socket head  19  either in a clockwise direction (“on”) or in a counterclockwise direction (“off”). Thus, as shown in FIG. 1, clockwise movement of socket head  19  will cause socket  19  and hence nut  22  to advance on conventionally threaded bolt  24  while counterclockwise movement will cause the nut to retreat. Wrench body  12  includes a case  26  containing the conventional ratchet mechanism (not shown). A neck  28  extends outwardly from the case at a lower portion thereof. Neck  28  is undercut to provide a shoulder  30  and a flat land  32 , with shoulder  30  extending from the land to the top surface  31  of the wrench body. Land  32  and surface  31  are generally parallel to each other. Shoulder  30  is provided with a centrally disposed v-shaped notch  54  which extends between top surface  31  and land  32 . 
     A pivot pin  34  is press-fit in wrench body  12  so that it extends upwardly from a central portion of land  32 . An enlarged handle retaining head  36  extends radially outwardly from the upper end of pivot pin  34 . 
     Wrench handle  14  includes a proximal enlarged rectangular end portion  38 , an intermediate shaft portion  40 , and a distal grip portion  42 . Rectangular portion  38  is provided with a cylindrical opening  44  having a diameter only slightly larger than the diameter of pivot pin  34  to enable the handle to fit snugly so that it can be freely rotated on pivot pin without significant wobble. Pivot pin  34  includes a spring-loaded detent ball  48  (spring not shown) which engages a circumferential chamfer  50  when the handle is locked in position (FIG. 1) and which rides along a chamfer  52  when the handle is unlocked or freed for cranking motion, as the position shown in FIG. 4 in phantom lines. 
     Returning to shoulder  30 , it is seen that notch  54  forms a 90° angle through the intersection of walls  53  and  55  cut into shoulder  30 . Depending upon the position of handle  14 , it should be understood that either of the corners  14   a  or  14   b  can complementarily mate within notch  54 . 
     In the illustrated embodiment of FIG. 2, the v-shaped notch  54  being cut at a 90° angle, only allows handle  14  to be positioned with centers at 45 degree intervals. Of course, this necessarily means that handle  14  is only allowed to move along a 180° sweep with respect to wrench body  12 . From the perspective of protecting the integrity of corners  14 A,  14 B and walls  53 ,  55 , from spaulling, chipping and general wear, the limited number of positions available due to the v-shaped notch has been found to be superior to other designs, such as those which use splines. The limitation of the number of available indexable positions has been found to have had no practical effect on performance. 
     Distal enlarged end  38  of handle  14  has a leading edge  60  having generally parallel top and bottom surfaces  62  and  64  and a planar face  63  confronting shoulder  30 . Leading edge  60  is delimited by the opposed corners  14 A and  14 B, which are also formed as 90° corners. The face  63  is perpendicular to top and bottom surfaces  62  and  64 , and is dimensioned to provide a deminimus gap between shoulder  30  and itself when in the straight locked position, as seen in FIG.  1 . Likewise, there is a deminimus gap between corners  14 A,  14 B and walls  53  and  55  of notch  54  when handle  14  is indexed in one of the other positions as seen in FIGS. 2 and 3. Thus, even with this deminimus gap, forces applied to the wrench handle are transmuted to the wrench body at the interface of the mating faces. Again, in the illustrated embodiment of FIG. 2, the v-shaped notch insures a good mating fit. 
     In a particularly preferred embodiment, as illustrated in FIG. 5, a chamfer  70  is formed along shoulder  30  where it meets top surface  31  and a corresponding chamfer  72  is formed along the leading edge  60  where it meets bottom surface  64 . These chamfers facilitate operation of the wrench during indexing of the handle. 
     In operation, wrench handle  14  is movable from a first position as seen, for example, in FIG. 4, in which the handle is locked against angular movement with respect to wrench body  12  and shank  16 , to a second position in which the handle is unlocked or freed for cranking motion. In the second position, as seen in phantom lines, the handle  14  clears top surface  31  of wrench body  12 , which permits the handle to be freely rotated, full circle, about pivot pin  34 . This enables the wrench body to be cranked about the axis of the shank and a socket head and nut connected thereto. The handle may be rendered immovable with respect to the wrench body in only five different positions by moving the handle with respect to the wrench body to a position where the corners  14 A or  14 B are locked within notch  54 , or where face  63  is in confronting relationship with shoulder  30 , shown in FIG.  2 . When in these positions, detent ball  48  engages chamfer  50 , maintaining the handle in the desired position. When the handle is in this first position, the wrench can be utilized as a conventional socket or a ratchet wrench by simply adjusting the ratchet direction selector  18  as desired. 
     In order to move the wrench handle to the second and unlocked position, the user grips the underside of the handle adjacent to wrench body  12  and presses upon the retaining head  36  of the pivot pin with his thumb, exerting sufficient force to cause spring-loaded detent ball  48  to retract, thereby allowing the handle to move to the upper or unlocked position shown in phantom lines in FIG.  4 . When top surface  62  of the enlarged end  38  of the handle comes in contact with the undersurface of retaining head  36 , detent ball  48  rides along chamfer  52 , as explained earlier, allowing the handle to rotate freely about pivot pin  34 , but preventing it from moving inadvertently from the second position into the first position. 
     When in the second and unlocked position, the handle can be rotated full circle about pivot pin  34  while simultaneously causing wrench body  12  to rotate full circle about the axis of shank  16 . Thus the wrench can he “cranked” to rapidly turn off or turn on a nut or bolt head. If the user encounters substantial resistance, he can again set corners  14 A,  14 B within groove  54  or face  63  opposite to shoulder  30 , then set the handle again to the first position against the action of detent ball  38 . Chamfers  70  and  72  will facilitate the alignment and movement of the handle and head with respect to each other making this transition between the first and second positions possible even while the wrench socket is engaged. 
     In a second embodiment of the invention, as illustrated in FIGS. 7 and 8, a wrench in the form of breaker bar  100 , in accordance with the present invention, is illustrated. Breaker bar  100  includes a wrench body  112  and a shank pin  116  which operates generally like the wrench of the previously described embodiment. Shank  116  is pivotally mounted in a cavity  102  in the distal end of body  112  by way of pin  104  which passes through the shank and is mounted to arms  106  and  108  on either side of cavity  102 . In this way, as is well-reorganized in the art, the shank may pivot about pin  104  in order to orient the breaker bar handle  14  with respect to the shank, as desired. 
     The handle of the breaker bar  114  (shown cut away) and corresponding portions of wrench body  112  include a locking/reciprocating mechanism as previously described. Thus, breaker bar  100  may be used in either a first position in which the handle is locked against angular movement with respect to the wrench body (as illustrated in FIGS. 7 and 8) or in a second position which the handle is unlocked or freed for reciprocating motion. 
     In a third embodiment of the invention, as illustrated in FIGS. 9 and 10, a box wrench  200  in accordance with the present invention is illustrated. Open end wrenches could, of course, be used in lieu of box end wrenches. The box end wrench includes a wrench body  212  having a six point hex opening  202  which is dimensioned to mate with a correspondingly-sized head of a bolt  204 , so that the bolt can be either screwed down or loosened, as desired. The wrench body is attached to a handle  214 . Wrench body  212  and handle  214  are attached using the locking/reciprocating mechanism in accordance with the present invention. 
     While the present invention is described above in connection with a preferred or illustrated embodiment, this embodiment is not intended to be exclusive or limiting of the invention. Rather, the invention is intended to cover all alternative, modifications and equivalents which may be included within the spirit and scope of the invention as defined by the appended claims.