Abstract:
A self-adjusting wrench having a handle and a jaw member rotationally attached thereto. A smoothly curved handle face opposes a planar face on the jaw member which adjusts for distance from the curved handle face by following a generally circular path around a pinned attachment of the jaw member to the handle. A spring or similar biasing device continuously urges the jaw member toward the handle thereby making the device self adjusting to the size of the object placed between the jaw member and the curved handle surface.

Description:
FIELD OF THE INVENTION 
   The disclosed device relates to a self adjusting self tightening wrench. More particularly it relates to a wrench with a handle and rotationally pivoting jaw member which form a substantially parallel grip on objects throughout the range of rotation of the jaw member which will accommodate an infinite number of sizes of objects to be rotated by the wrench between the wrench&#39;s minimum and maximum mouth openings. 
   BACKGROUND OF THE INVENTION 
   Adjustable wrenches in the past have generally been of a type which laterally translates a moveable jaw member away from and toward and fixed working surface on the wrench handle. By translating the jaw member further away, using a geared mechanism, the distance between the fixed working surface on the handle and the moveable working surface of the jaw member may be increased to a finite distance. This allows such adjustable wrenches to accommodate a range of sizes of bolts, pipes, nuts, or other objects needing rotational movement. Similar adjustable pliers allow for the increase of the dimension between the working surface of the fixed handle and the pivoting jaw member by slidable engagement of cooperatively engageable tracks on both the handle and the jaw member. This again allows for adjustment of the distance between the working surface of the jaw member and the handle to be adjusted to accommodate the object being gripped for rotation. 
   Such conventional adjustable wrenches do however provide for a continuous and automatic adjustment of the force or tightness of the “grip” which the wrench had on a work piece. Consequently, because the adjustable wrench was not sized to the object being worked on, slippage occurred of the wrench on the object being turned resulting in a “knuckle buster” which has been a constant source of aggravation to the user of such wrenches. Further, such adjustable wrenches generally require some movement of an adjusting mechanism by the user which requires two hands and a reasonable high amount of dexterity. 
   As such, there is a pressing need for an easily functioning adjustable wrench. Such a wrench should automatically adjust to the object placed between its jaws. Such a wrench should not slip when twisted and should ideally increase the force of the grip on the object being rotated between the jaws when the force on the wrench is increased. Further, such a wrench should maintain relatively equal pressure on both sides of the object being twisted to maximize grip and minimize distortion of the object of the wrench&#39;s force. 
   SUMMARY OF THE INVENTION 
   The above problems, and others are overcome by the herein disclosed automatically adjusting self tightening wrench. The device is composed of a handle and rotating jaw member having a gripping surface area on a distal face of the jaw member. The jaw member is rotationally attached to the handle at the opposite end from the area to be gripped by the user. The rotation of the jaw member is generally about a pin or axle used to secure it to the distal end of the handle. In the current best mode, the jaw member rotates about the pin and into a slot grooved into the handle just below the pin thereby allowing the jaw member to rotate on the pin with the attachment end of the jaw member rotating into the slot. 
   The gripping surface area of the jaw member at an angle substantially normal to the center axis of the elongated handle when the jaw member is in a fully biased position rotated to its closest point to the work surface formed on the end of the handle. The handle gripping surface is formed on a working face portion shaped like an arc. When the jaw member rotates about the axle, the jaw gripping surface area of the jaw member becomes increasingly distant from the handle gripping surface formed on the arced face of the handle because both circles have different center points. This increase in distance allows the device to accommodate larger and larger objects between the jaw gripping surface and the handle gripping surface as the jaw member is rotated to increase the distance of the planar face of the jaw member and the jaw gripping surface thereon, away from the handle gripping surface on the handle face. 
   A biasing means such as the spring shown in the current best mode of the device, is in communication at one end with the static handle and at the other with the rotating jaw member and biases the jaw gripping surface area on the planar face of the jaw member toward the handle gripping surface formed on the arcing face of the handle, at all times. This allows the device to immediately self adjust to the diameter of the object placed between the gripping surface on the face of the jaw member and the jaw gripping surface on formed on the face of the handle opposite the end to be held by the user. 
   Unique to the disclosed device is the maintaining of generally parallel contact between gripping surfaces no matter what the size of the object inserted therebetween. This is accomplished by the arc shape forming the working face on the handle on which the handle gripping surface resides. By forming the working surface in an arc, and forming the jaw gripping surface on a generally planar face that is normal to the center axis of the handle at its closest position, when the jaw is rotated about the axle pin on the handle, a generally parallel contact of both gripping surfaces on the object therebetween is maintained. As can be seen, the actual surface area of an object touching the arced surface of the gripping end of the handle is very small thus providing the generally parallel contact between both gripping surfaces at all points in the rotation of the jaw member. 
   In the current best mode, teeth or a gnarled surface would be provided on both the arced face of the handle and the planar face of the jaw member. This allows for a better frictional connection between the object being rotated between the jaw member and the handle during use. The formed teeth or other frictionally engaging surface are best angled to allow maximum grip when the wrench is torqued in the direction of object rotation which occurs when the gripping end of the handle is forced toward mouth opening formed between the jaw member and the arced handle face. The arrangement of angling the teeth would also allow the device to slip when the wrench is pulled in the opposite direction of intended rotation which occurs when the hand grip end of the handle is pulled away from the mouth opening. This allows the device to slip in one direction and grip progressively harder in proportion to the force applied in the other direction. 
   Finally provided to make the device even more user friendly is the thumb grip on the exterior surface of the jaw member. This area of the jaw member is notched or otherwise surfaced for easy frictional engagement of the user&#39;s thumb or finger with the jaw member. This allows the user, with only one hand, the place the mouth opening of the device over the object for rotation and then to pull open the jaw member still using one hand by simply pressing with the thumb or finger on the thumb grip to overcome the force of the biasing means and remove or readjust the device from the object being turned. 
   Accordingly, it is the object of this invention claimed herein to provide a simplified and easy to use self adjusting wrench which will tighten its grip on the object being turned as the force applied to the handle is increased. 
   It is another object of this invention to supply such a self adjusting wrench that will relax its grip on the object being turned and slip when pulled in the opposite direction of intended object rotation. 
   It is still another object of this invention to provide such a self adjusting wrench which has a biased jaw allowing the user to use the device with only one hand and secure it over the object to be turned. 
   It is a still further object of this invention to provide an easy thumb release on the jaw of the device such that the user can release it from engagement with the object to be turned still using one hand and the thumb to overcome the biasing means. 
   It is yet another object of this invention to provide a self adjusting wrench which by using a curved gripping surface on the handle and planar surface on the jaw maintains a substantially parallel engagement upon the object being turned by the wrench and substantially equal imparting of force by each working face upon the object turned. 
   Further objectives of this invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon. 

   
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
     The accompanying drawings which are incorporated in and form a part of this specification illustrate embodiments of the disclosed processing system and together with the description, serve to explain the principles of the invention. 
       FIG. 1  depicts a side view of the disclosed self adjusting wrench showing it with the jaw gripping surface in the closest position to the handle gripping surface. 
       FIG. 2  depicts a side view of the disclosed self adjusting wrench showing the jaw gripping surface of the jaw member in the position furthest from the jaw gripping surface of the handle. 
       FIG. 3  shows a side view of the device with the handle cut away to reveal the interior cavity for travel of the jaw member on the axle pin and the biasing means. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1–3  preferred embodiments of the disclosed device  10  with  FIG. 1  depicting a side view of the disclosed self adjusting wrench device  10 . The device  10  features a handle  12  having a grasping end  14  and a working end opposite the grasping end  14 . 
   A rotatingly mounted jaw member  18  is mounted to the handle  12  at th working end  16  using a pin  20  or axle which communicates into the handle  12  and jaw member  18  and attaches the jaw member  18  in rotational engagement with the handle  12  about the working end  16  of the handle  12 . 
   On the working end  16  of the handle  12  arc shaped handle working face  22  is formed and on this handle working face  22  a handle gripping surface  24  is formed. The current best mode of the device  10  features the handle working surface  22  in an arc and forming the jaw gripping surface  26  on a generally planar face  28  of the jaw member  18  opposite the handle working face  22 . By forming the jaw gripping surface  26  on a substantially planar jaw planar face  28  and rotating that gripping surface  26  around the arced handle gripping surface  24  the object  30  which is to be rotated is gripped at two substantially parallel contact points no matter what rotational position the jaw member  18  and jaw member gripping surface  26  is located in relation to the handle gripping surface  24  on the arced handle working face  22 . This curve or arc of the handle working face  22  and the handle gripping surface  24  thereon, combined with the rotation of the jaw gripping surface  26  around it during rotation of the jaw member  18  thus provides substantially parallel contact points on both sides of a gripped object  30  no matter what point the jaw member  18  has rotated to accommodate the size of the object  30 . This of course substantially equalizes the pressure imparted to both sides on which the object is gripped by the device  10 . 
   The rotation of the jaw member  18  is as noted provided by the axle formed by the pin  20  used to secure the jaw member  18  to and in rotational engagement at the working end  16  of the handle  12 . In the current best mode, the jaw member  18  rotates about the pin and into a slot  32  grooved into the handle  12  just below the pin  20  providing a relief into which one end of the jaw member  18  may rotate into on the handle  12 . 
   Automatic adjustment of the device  10  to the size of the object  30  is provided by the rotation of the jaw member  18  about the pin  20 . As the jaw member  18  rotates, the jaw gripping surface  26  on the jaw planar face  28  follows a circular path around the pin  20  but becomes increasingly distant from the handle gripping surface  24  formed on the arced handle working face  22 . This resulting increase in distance allows the device to accommodate larger and larger objects  30  between mouth  34  formed between the jaw gripping surface  26  and the handle gripping surface  24 . The maximum size of the mouth  34  so formed would be determined by the maximum distance of the jaw gripping surface  26  from the handle gripping surface  24  and also by changing the angle of the elbow  36  where it intersects the first jaw member strut  36  and angles back on the second jaw member strut  38  to determine the position of the jaw planar face  28  in relation to the handle working face  22 . Increasing the angle of the elbow  36  would increase the smallest size of the mouth  34  and the resulting largest size of the mouth depicted in  FIG. 3 . Also seen in  FIG. 3  are the two substantially circular paths  51  and  52  followed by the handle working face  24  and the jaw planar face  28  respectively. These offset circular paths followed by both surfaces thus increase and decrease the distances between the two allowing for the size of the mouth  34  to increase and decrease for the size of the object  30 . 
   A means to bias the jaw gripping surface  26  toward the handle gripping surface  24  is provided in the current best mode by the spring shown in the current best mode of the device  10 . The spring  42  also in the current best mode has an elbow shape and is sized to reside inside the slot  32  during use. As depicted the spring  42  is attached inside the slot  32  at a first end using a set screw  44  and to the jaw member  18  at the opposite end in frictional engagement with an aperture  46 . This type of spring bends at the spring elbow  46  and therein biases the jaw member  18  and affixed jaw gripping surface  26  area on the jaw planar face  28  under biased force toward the handle gripping surface  24  formed around the arced handle working face  22 . This bias allows the device to immediately self adjust to the diameter of the object  30  placed in the mouth  34  by biasing the jaw member  18  back toward the handle gripping surface  24  at all times. It also provides the ability to used the device with only one hand by simply engaging the object to be turned into the mouth and rotating the handle  12  toward the mouth side of the device  10 . 
   In the current best mode, teeth  48  or an otherwise gnarled surface would be provided on both the arced handle gripping surface  24  and the jaw planar face  28  of the jaw member  18 . These teeth  48  allow for a better frictional connection between the object  30  being rotated and the gripping surfaces on the jaw member  18  and the handle  12  during use. The formed teeth  48  are best angled to allow maximum grip when the wrench is torqued in the direction of object rotation which occurs when the gripping end  14  of the handle  12  is forced toward mouth side of the handle formed between the jaw member and the arced handle face. The arrangement of angling the teeth  48  would also allow the device  10  to slip when the wrench is pulled in the opposite direction of intended rotation which occurs when the griping end  14  of the handle  12  is pulled away from the mouth opening. This allows the device to slip in one direction and grip progressively harder in proportion to the force applied in the other direction. The curved surface of the hand gripping surface  24  tends also to turn into the object being held grabbing it tighter as more force is applied. 
   Finally, in the current best mode of the device  10  a biasing release is provided to make the device even more user friendly and useable by one hand. This is provided by the thumb grip  50  on the exterior surface  52  of the jaw member  18  and could be surfaced with teeth  48  or other frictional engagement style surfacing. The thumb grip  50  allows the user, with only one hand, to place the mouth  34  opening of the device over the object  30  for rotation and then to pull open the jaw member  18  still using one hand by simply pressing with the thumb or finger on the thumb grip  50  to overcome the force of the biasing means and remove or readjust the device  10  from the object being turned. 
   While all of the fundamental characteristics and features of the automatically adjusting self tightening wrench have been shown and described, it should be understood that various substitutions, modifications, and variations may be made by those skilled in the art, without departing from the spirit or scope of the invention. Consequently, all such modifications and variations are included within the scope of the invention as defined by the following claims.