Patent Publication Number: US-2003233914-A1

Title: Pliers for clamping a hose or tube

Description:
BACKGROUND OF INVENTION  
       [0001] In a principal aspect the present invention relates to a pliers which is especially useful for clamping hoses and other objects and for maintaining a tightly closed or clamped position on the object such as a hose.  
       [0002] Vehicle repair operations and other mechanical repair situations often require that a hose or some other object be gripped and clamped so as to maintain the hose or the object in a desired compressed condition. This result is also often desired in medical applications wherein a clamping action is desired to close a vessel for example. However, the clamping action must be limited in terms of its pressure and degree of closure so that when a clamped condition is reached, the vessel will not be ruptured or damaged. The same desire is applicable to vehicle repair and other mechanical repair operations involving hoses or other items that must be clamped or joined together from time to time.  
       [0003] Various prior art proposals and solutions have been tendered to accomplish such objectives. Adjustable clamps comprise one such solution. So called “channel locking” pliers provide another solution. Various types of tools have been proposed including tools of the type of disclosed in U.S. Pat. No. 5,005,450 for a self locking tool and various patents cited therein. Other types of clamping plier devices are depicted in the following U.S. patents U.S. Pat. No. 682,701; No. 2,574,909; No. 1,717,726; No. 1,450,875; No. 1,026,270; No. 2,370,308; No. 3,257,878; No. 2,787,925; and 3,126,775. Each of these solutions has benefits and disadvantages. There has remained, however, a desire to provide a clamping mechanism or tool for hoses and other objects which provides a positive closure of the clamping jaws with limited clamping pressure or travel of the jaws toward one another yet which provides a retentive force that will appropriately close a hose and hold with the desired degree or amount of pressure. These and other objectives inspired the development of the present invention.  
       SUMMARY OF THE INVENTION  
       [0004] Briefly, the present invention comprises a pliers construction which includes four pivotally connected members. Thus included in the pliers construction is a first handle member with a first jaw, a second handle member which is pivotally connected to a separate, second jaw and the first handle member, and a linkage bar pivotally connected to the second jaw at one end and engaging its opposite end by means of a cam pin with a pair of opposed cam slots defined in the first and second handle members. The interaction of the cam pin carried by the link and the cam slots associated with the handles provides a locking action when the handles are moved together. With the particular construction of the invention it is possible to provide a clamping action more easily because the handles may be more closely spaced and the extent of travel of the handles reduced in order to move the jaws between the open and clamped positions. Thus, the clamping action by the pliers can be affected more easily by a mechanic or other user of the pliers construction. The jaws may include optional pivotal plates which typically and preferably comprise flat planer plates that apply opposite and equally opposed forces of the opposite sides of a hose or other object when the jaws are closed.  
       [0005] Thus it is an object of the invention to provide an improved clamping pliers.  
       [0006] It is a further object of the invention to provide a clamping pliers comprised of four separate elements including a first lever arm or handle which includes an integrated jaw, a second, separate lever arm or handle, a separate second jaw, and a connecting link. The two handles and jaws are pivotally connected and the link interconnects the second jaw with overlapping cam slots in the handles.  
       [0007] It is yet another object of the invention to provide a pliers construction which enables efficient use of amount of travel associated with the handles of the pliers in order to effect a clamping action.  
       [0008] Yet a further object of the invention is to provide a four component clamping pliers which includes a single pivot for two handles and the jaws of the pliers, and a link which controls the interaction of the movement of the handles and jaws.  
       [0009] Yet another object of the invention is to provide a clamping pliers which is easily manufactured, easily utilized by mechanics, rugged and economical.  
       [0010] These and other objects, advantages, and features of the invention will be set forth in the detailed description which follows.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
     [0011] In the detailed description which follows reference will be made to the drawing comprised of the following figures.  
     [0012]FIG. 1 is a plan view of the pliers of the invention wherein the handles have been moved to the closed position;  
     [0013]FIG. 2 is a plan view of the pliers of FIG. 1 as viewed from the opposite side thereof;  
     [0014]FIG. 3 is a plan view of the pliers of FIG. 1 wherein the handles have been moved to the open position;  
     [0015]FIG. 4 is a plan view of the pliers of FIG. 3 as viewed from the opposite side thereof;  
     [0016]FIG. 5 is a plan view of the first handle associated with the pliers of FIG. 1;  
     [0017]FIG. 6 is a plan view of the second handle of the pliers of the invention;  
     [0018]FIG. 7 is a plan view of the second jaw of the pliers of the invention; and  
     [0019]FIG. 8 is a plan view of the link connecting the second jaw with the cam ways associated with the handles.  
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0020] Referring to the figures, the clamping pliers includes a first handle  10 , a second handle  12 , a second jaw  14 , and a link  15  as separate and individual parts. Optional jaw plates  16  and  18  are provided for attachment to the separate jaws of the pliers.  
     [0021] The first handle member or lever arm  10  includes handle section  20 , a pivot or center portion  22  including a pivot opening  23  and a first jaw  24  (see FIG. 6). The second handle or lever arm  12  includes a handle section  30  and a pivot section or center portion  32  with a pivot opening  33 . The second lever arm  12  does not include an integral jaw. Rather there is provided a second jaw  14  with an active jaw end  40  and a pivot section  42  and pivot opening  43 . The pivot openings  23 ,  33 ,  43  of the lever arm  10 , lever arm  12  and second jaw  14 , respectively are all commonly connected by a single pivot pin  52  for pivoting about a common axis.  
     [0022] The first lever arm  10  includes a forward jaw section  24  to which is optionally attached the jaw plate  16 . The jaw plate  16  comprises a parallel planar plate member  17  which is opposed to a parallel planar plate member  19  associated with jaw plate  18  so that when the jaw plates  16  and  18  are moved together they will uniformly compress a hose, for example.  
     [0023] The second jaw  14  is connected by link  15  to both the first lever arm  10  and second lever arm  12 . More particularly the link  15  includes a pivot attachment  60  to second jaw  14  which is positioned at a fixed radius  62  from the pivot pin  52 .  
     [0024] The link  15  further includes a pivot pin  64  which defines or comprises a cam member that engages with a slot or camway  66  in the lever arm  10  and camway or slot  68  in the lever arm  12 . The camway  66  and  68  are spaced from the pivot pin  52  by a radial distance which is variable along the length of each camway  66 ,  68 .. The camway  66  and  68  are overlapping one with the other and, in the embodiment shown, are straight line slots with an increasing radial distance from the center axis or pivot  52  as the handles  10 ,  12  are spread in equal and opposite amounts. When the lever arms  10  and  12  are in the closed position, then, the shortest radial distance of the respective camways  66  and  68  to pivot  52  are aligned together, and this alignment and engagement by pivot pin  52  causes the pliers to be in a substantially locked or rigid position. Manual actuation is required to release the handles  20  and  30  and thus release the clamping action.  
     [0025] Various other shapes and directions of camways may be utilized in the construction of the invention. For example, arcuate camways may be provided. The length of each camway  66 ,  68  may be distinctive. Detents (not shown) may be provided in the camways. The camways or cam pathways  66 ,  68  intersect at some angle, which may be varied to provide different jaw closure rates. Importantly the camways  66 ,  68  must overlap inasmuch as a single cam pivot pin  64  simultaneously engages both camways  66 ,  68 . The clamping action is, however, attained by the interaction of the cam pivot pin  64  and the camways  66 ,  68  and the pressure that results when attaching the pliers on a hose or other object which is to be gripped.  
     [0026] The construction may be altered or amended without departing from the spirit of the scope of the invention. The invention is therefore to be limited only by the following claims and equivalents thereof.