Abstract:
A bar clamp having a first jaw assembly, a second jaw assembly and a bar. The first and second jaw assemblies are mounted on the bar which is movable relative to the second jaw assembly. A trigger is operatively associated with the bar and is adapted to be activated to move the bar and the first jaw assembly relative to the second aw assembly in one direction. A release mechanism on the second jaw assembly is operatively associated with the bar and is adapted to be activated in order to permit the bar and the first jaw assembly to move relative to the second jaw assembly in the opposite direction.

Description:
BACKGROUND 
     The present invention relates to a bar clamp and more particularly to an improved ratchet type bar clamp in which the jaws may be moved toward each other step-by-step and the jaws may be moved apart when desired. 
     Ratchet type bar clamps have been in use for a number of years. They usually comprise a jaw mounted on a moveable bar and another jaw mounted on a stationary handle assembly. A trigger is provided in the handle assembly which when pressed will move the jaws closer together in a series of steps. When is desired to move the jaws apart, a release button is activated to move the jaws apart. Existing ratchet type bar clamps are complicated and expensive to manufacture and assemble and many are not easily capable of being used by one hand. 
     Objects 
     The present invention overcomes these drawbacks and has for one of its objects the provision of an improved bar clamp which is simple to use. 
     Another object of the present invention is the provision of an improved bar clamp in which the jaws can be advanced toward each other with one hand. 
     Another object of the present invention is the provision of an improved bar clamp in which the jaws can be released to moved away from each other by the same hand. 
     Another object of the present invention is the provision of an improved bar clamp in which the jaws can be easily placed in position to spread apart an article as well as to tighten on an item 
     Another object of the present invention is the provision of an improved bar clamp which is simple and inexpensive to manufacture. 
     Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings forming a part of the specification, wherein: 
     Drawings 
     FIG. 1 is a perspective view of a bar clamp made in accordance with the present invention. 
     FIG. 2 is a sectional view of the bar clamp taken along line  2 — 2  of FIG.  1 . 
     FIG. 3 is a sectional view similar to FIG. 2 showing the position of the parts when the jaws are to be moved closer together. 
     FIG. 4 is a sectional view similar to FIG. 2 showing the position of the parts when the jaws are to be moved apart. 
     FIG. 5 is a detail showing the position of some of the parts when the jaws are to be moved toward each other. 
     FIG. 6 is a detail showing the position of some of the parts when the jaws are to be moved away from each other. 
     FIG. 7 is a plan view showing the manner of switching one of the jaws to a position where the jaws are used to spread an item apart. 
     FIG. 8 is a plan view similar to FIG. 7 showing the jaws being moved apart from each other in an item spreading position 
     FIG. 9 is in perspective detail view showing the manner of positioning the bar into one of the jaw bases. 
     FIG. 10 is a plan view of two control plates used with the present invention. 
     FIG. 11 is a sectional view taken along line  11 — 11  of FIG.  7 . 
    
    
     DESCRIPTION 
     Referring to the drawings, the bar clamp  1  of the present invention comprises a straight bar  2  having a front end  3 , a rear end  4 , a top edge  17  a bottom edge  18  and side walls  19 . The front and rear ends  3 - 4  each have an opening  11  and a guide pin  12  extending therefrom. Removably mounted on front end  3  is a first jaw assembly  5  which comprises a gripping face  6 , a body  7 , and depending a base  8 . The base  8  has an opening  9  (FIG. 8) into which the front or rear end  3 - 4  end  3  of the bar  2  may be inserted and a side hole  10  extending from one face of base  8  through to the other face  33 . The guide pin  12  is adapted to slide in a groove  13  in opening  9  in the base  8  to guide the bar into the opening  9  in the base  8 . The side hole  10  has inner end  14  which is plain and smooth and an outer end  15  which is threaded. The jaw assembly  5  is held in place by a threaded wing nut  16  inserted in the inner end  14  of the opening  10  in base  8  of the jaw assembly  5  and through the opening  11  in the bar  2  and tightened into the threaded outer end  15  of side hole  10  in the base  8 . 
     A second jaw assembly  20  comprises a gripping face  21 , a body portion  22  and a base portion  23  depending therefrom. The base portion  23  of the second jaw assembly  20  has a handle portion  24  extending downwardly therefrom. The base portion  23  is substantially hollow and has front and rear walls  25 - 26  with openings  27 - 28  therein which are in alignment with each other and through which the bar  2  extends. The handle portion  24  has a trigger  30  which is pivotally mounted therein at  31  and which has its upper active head  32  extending into the base portion  23  through opening  33 . 
     Within the hollow base portion  23  the bar  2  has a control advancing plate  35  and a control release plate  40  mounted thereon. The advancing plate  35  has an opening  36  therein through which the bar  2  extends and a lower portion  46 . The opening  36  has upper and lower edges  37  and  38 . A spring  39  is interposed between the rear wall  26  of the base portion  23  and the advancing plate  35  in order to hold the advancing plate  35  in a position substantially perpendicular to the bar  2 . In this position the upper and lower edges  37 - 38  of the advance plate  35  do not engage the upper and lower edges  17 - 18  of the bar and do not affect the bar  2 . 
     Between the advance plate  35  and the front wall  25  of the base  23 , the base  2  has the release plate  40  mounted thereon which also has an opening  41  therein through which the bar  2  extends. The opening  41  has upper and lower edges  42 - 43  and a lower portion  47 . A spring  44  is mounted between the release plate  40  and a collar  45  adjacent the advancing plate  35 . The release plate  40  is normally in a substantially angled position (FIG. 2) with its upper portion  48  resting on pivot stop  49  and the lower portion  47  resting on release button  50  on it upper edge  42  bearing against the upper edge  17  of the bar  2 . In this position, the bar  2  cannot move rearwardly because it is locked in place by the upper edge  42  of the opening  4  in the release plate  40  bearing against upper edge  17 . A release button  50  extends through an opening  51  in the lower part of the front wall  27  base  23  and bears against the lower portion  47  of the release plate  40 . 
     With the position of the parts as shown in FIG. 4 squeezing the trigger  30  with one hand will pivot the active head  32  of the trigger  30  so that it will press against lower portion  46  of the advance plate  35  to angle it to cause the upper edge  37  of the opening  36  to bear against the upper edge  17  of the bar  2  and will move the bar  2  forward to move the jaw assembly  20  forward toward the first jaw assembly  5 . In this position the gripping faces  6 - 21  will grasp an article (not shown) between them. When the trigger  30  is released the spring  39  will move the advance plate  35  back to its angled position. When it is desired to move the second jaw assembly  20  in the opposite direction to release an article from the grasp of the gripping faces  6 - 21 , the release button  51  is pressed inwardly with the thumb of the same hand that is holding the handle assembly  24  in order to cause it to bear against the lower portion  47  of the release plate  40  and move the release plate  40  around pivot stop  49  to a position substantially perpendicular to the bar  2  as shown in FIGS. 4 and 6. This releases the hold or lock that the upper edge  42  of the opening  41  has on the upper surface  17  of the bar  2  and permits the bar  2  to be moved in the opposite direction and thereby move the second jaw assembly  20  away from the first jaw assembly  5 . When the release button  50  is released the spring  44  will move release plate  40  back to its angled position thereby again locking the bar  2  against rear end movement. 
     It will be seen that the jaws can be moved toward each other by one part of the hand e.g. first four fingers and the other part of the hand (e.g. the thumb of the same hand) can then be used to release the jaw assemblies  5 - 20  for movement in the opposite direction. 
     If desired, the first jaw assembly  5  of the present invention can be removed from the front end  3  of the bar  2  by unscrewing and removing the wing nut  16 . The first jaw assembly  5  can then be placed on the rear end  4  of the bar  2  by placing the rear end  4  into the openings  9  in the base  8  from its outer end and tightened thereon by the wing nut  16  so that the gripping faces  6 - 21  face away from each other. In this position, the bar clamp be used to spread articles apart. 
     It will thus be seen that the present invention provides an improved bar clamp which is simple to use, in which the jaws can be advanced toward each other with one hand, in which the jaws can be released to move away from each other by the same hand, which is simple and inexpensive to manufacture and in which the jaws can be easily placed in position to spread apart an item as well as to tighten on an item. 
     As many and varied modification of the subject matter of this invention will become apparent to those skilled in the art from the detailed description given hereinabove, it will be understood that the present invention is limited only as provided in the claims appended hereto.