Patent Publication Number: US-6216564-B1

Title: Universal wrench

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a universal wrench. The wrench has an open wrench body that is attached to the end of a handle or a device formed at the end of a handle, for clamping and holding fast, and then releasing a bolt head or like connecting element, or rods, pipes, etc. 
     Known wrenches of this kind have the disadvantage that round bolt heads or like connecting elements, and rods and pipes cannot be securely clamped, held fast, and released. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to provide a universal wrench that with its wrench body is able to securely clamp, hold fast, and release even round bolt heads and like connecting elements, and rods, pipes and like parts of different shape and size. 
     This object is achieved according to the invention, by a universal wrench having at least one open wrench body attached at the end portion of a handle or a device formed at the end of a handle. The wrench body is pivotable in a gripping plane relative to the handle. A shaft is attached to the handle and stands perpendicularly to the gripping plane. First and second jaws are mounted to pivot about the shaft in the gripping plane. A guide is provided on the first jaw and runs at right angles to the gripping plane. A rack is provided on the second jaw at right angles to the second jaw. The rack is guided for longitudinal displacement in the guide and has teeth directed towards the handle. A series of teeth are provided at the end portion of the handle, with the teeth arranged in a circular arc with a mid-point formed by the shaft. These teeth engage the teeth on the rack. 
     It has been found to be particularly advantageous for the handle to have an abutment portion with a tooth system with rounded recesses and projections. The wrench body has two jaws that are reciprocally displaceable. The first jaw is rotatable about a shaft mounted in the handle and is held in the clamping position by a spring. The second jaw has recesses and projections that match those of the abutment portion. The jaws are provided on their mutually facing inner sides with recesses that ensure better seating on the part to be clamped. 
     To accomodate conventional hexagonal nuts, the recesses have surfaces that include an angle of 120 and form sides of an equilateral triangle. 
     The inner sides of the jaws are provided with edges to ensure a good grip on round parts such as pipes. The inner sides of the jaws are also provided with teeth that form gripping surfaces. A ratchet-like latching between the jaws and the handle can result from appropriately constructing and arranging the teeth and the spring. 
     A further advantage results from a spring that has one end mounted on the shaft on the handle or on a pin elastically mounted in the handle. The other end of the spring is mounted on the jaw that is pivotably held by the shaft. The handle and the jaw are thus better held in the desired position to assure that a bolt or other connecting element is securely held. 
     Possibile uses of a universal wrench according to the invention are expanded when the abutment portion is connected to the end of the handle via a shaft lying in the gripping plane of the wrench body. In this arrangement, the abutment portion can be rotated perpendicularly to the gripping plane, as is known from Swiss Patent 382,044. This arrangement is therefore not shown and described in more detail. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     Preferred embodiments of the invention will be explained in more detail with reference to the accompanying drawings, in which: 
     FIG. 1 shows a plan view of the universal wrench, 
     FIG. 2 shows a longitudinal section through the universal wrench shown in FIG. 1, 
     FIG. 3 shows a plan view of the first jaw, 
     FIG. 4 shows a plan view of the second jaw. 
     FIG. 5 is a view similar to FIG. 1, but showing the reversal wrench in a position in which the bias of a spring urges the jaws of the universal wrench to their closed position, and 
     FIG. 6 is a view similar to FIG. 1, but showing the jaws in an opened position wherein the jaws are opened further than in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The universal wrench has an open wrench body  2  and a handle  1 . The handle  1  has an abutment portion  14  with teeth that are formed by rounded projections  21  and rounded recesses  19 ,  20 , arranged on a circular arc, the midpoint of which coincides with the longitudinal axis of rotary shaft  5 . The wrench body has two reciprocally displaceable jaws  15 ,  16 . For purposes of this specification jaw  16  is designated the first jaw and jaw  15  is designated the second jaw. Second jaw  15  carries projections  25 ,  26 ,  27  and recesses  28  on a slider rack  30  that is guided in first jaw  16 . The projections and recesses are arranged in a straight line and match those on the abutment portion  14  with which they engage. Shanks  35 ,  36  are attached to first jaw  16  and are provided with mounting bores and are pivotably mounted on the shaft  5 . Shanks  35 ,  36  are perpendicular to a guide surface running at right angles to first jaw  16  and forming, together with shanks  35 ,  36 , a guide  29  for the rack  30 . The first jaw  15  is attached at right angles to the untoothed rear side of rack  30 . First jaw  16  forms with its lateral shanks  35 ,  36  a forked enclosure of the toothed abutment portion  14  of the handle  1 . Shanks  35 ,  36  have a semicircular shape at their lower ends  31 ,  32 , engaging a latch pin  33  that is enclosed by a sleeve  34  of elastic material and fastened in a bore of the handle  1 . First and second jaws  16  and  15  respectively are secured in different pivoting positions relative to the handle  1 , because latch pin  33  abuts and presses on the smooth arcuate lower ends  31 ,  32  of the arcuate shanks. 
     To support positioning on a connecting element to be gripped, a spring  37  is attached at one end to shaft  5  in handle  1  and is attached at its other end  38  to second jaw  16 . In another embodiment shown in broken lines, spring  37 , is attached to latch pin  33 . 
     The mutually facing sides of the first and second jaws  16  and  15 , respectively are provided with recesses  15 ′,  16 ′. The clamping faces are equipped with teeth or ribs  15 ′″,  16 ′″. Corners  15 ″,  16 ″ are provided at the transition from the forward, obliquely running faces of the recesses to the straight running surfaces of the clamp jaws. The corners  15 ″,  16 ″ serve to enclose round pieces and are defined by notches n which extend transverse to parallel surfaces ps. 
     In operation, pivoting the abutment portion  14  of handle  1  to the right displaces jaws  15 ,  16  in an opening direction. The universal wrench can thus be seated on connection elements of different sizes, this seating being facilitated in that the play between the jaws and the parts to be gripped can easily be increased by pivoting the handle  1 . If the abutment portion of the handle is now pivoted in the opposite direction, to the left, jaws  15 ,  16  clampingly engage the article to be gripped. 
     The invention is not limited to the universal wrench illustrated. The adjustable jaw wrench body can also be attached to the handle to rotate about an axis. Likewise, several wrench bodies can be provided on one handle. The wrench body can also be constructed with the abutment portion as an interchangeable component for other suitable universal wrenches. 
     For the purpose of an improved handling it is provided that the end of the grip is furnished with a covering.l′ out of rubber or plastic material which is conplemented with formings l″ and with a hanging link l′″.