Abstract:
A semi-automatic cable tie application tool including a power-actuated cylinder located within the grip portion of the housing and including a flexible cable extending between the piston rod of the cylinder and the tensioning/cutting mechanisms of the tool. The tool includes first and second pulleys for movably supporting and orienting the direction of travel of the cable.

Description:
[0001]    This application claims the benefit of U.S. provisional Application No. 60/220,763 filed on Jul. 26, 2000. 
     
    
     
       BACKGROUND OF INVENTION  
         [0002]    The present invention relates to a cable tie installation tool and, more particularly, to an improved semi-automatic tool for tensioning and cutting of cable ties.  
           [0003]    As is well known to those skilled in the art, cable ties (or straps) are used to bundle or secure a group of articles such as electrical wires or cables. Cable ties of conventional construction include a cable tie head and an elongate tail extending therefrom. The tail is wrapped around a bundle of articles and thereafter inserted through a passage in the head. The head of the cable tie typically supports a locking element which extends into the head passage and engages the body of the tail to secure the tail to the head.  
           [0004]    In practice, the installer manually places the tie about the articles to be bundled, inserts the tail through the head passage and then manually tightens the tie about the bundle. At this point, a cable tie installation tool is used to tension the cable tie to a predetermined tension.  
           [0005]    Prior art tools include both manually-actuated tools and power-assisted tools. As will be appreciated by those skilled in the art, manually-actuated tools are operated as a result of the installer physically squeezing a trigger mechanism, while power-assisted tools are typically operated by via a pneumatic cylinder/piston. With respect to such prior art power-assisted tools, this pneumatic cylinder/piston is located horizontally above the handle of the tool, and in-line with the actuating rod of such tool. However, the placement of the pneumatic cylinder/piston above the operator&#39;s hand results in an unbalanced weight distribution throughout the tool, which makes the tool more difficult to handle and leads to increased operator fatigue.  
           [0006]    There is therefore a need in the art for a semi-automatic cable tie application tool which is both ergonomical and user friendly. There is a further need in the art for a semi-automatic cable tie application tool having reduced weight, and which is reliable, compact and readily manufactured.  
         SUMMARY OF THE INVENTION  
         [0007]    The present invention, which addresses the needs of the prior art, relates to a tool for installation of a cable tie. The cable tie includes a head and an elongate tail extending therefrom. The tool includes a generally pistol-shaped housing having a barrel portion and a grip portion. The housing operatively supports a tensioning mechanism for tensioning the cable tie to a predetermined tension setting and a cutting mechanism for severing an excess portion of the tail from the tensioned cable tie. The tool further includes a power-actuated cylinder having a movable piston rod for operating the tensioning and cutting mechanisms. The cylinder is located within the grip portion and is generally aligned therewith. Finally, the tool includes a drive train for coupling the piston rod to the tensioning and cutting mechanisms whereby movement of the piston rod operates the tensioning and cutting mechanism.  
           [0008]    As a result, the present invention provides an ergonomically improved-power assisted tool having reduced weight and better handling characteristics. Moreover, the present invention provides a power assisted tool which maintains the fast cycle aspects of certain prior art power-assisted tools, but incorporates improved tensioning/cutoff mechanism technology. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is a perspective view of the semi-automatic cable tie application tool of the present invention with a portion of the housing removed for clarity;  
         [0010]    [0010]FIG. 2 is an enlarged view of the tool of FIG. 1;  
         [0011]    [0011]FIG. 3 is another enlarged view of the tool of FIG. 1; and  
         [0012]    [0012]FIG. 4 is still another enlarged view of the tool of FIG. 1.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]    The present tool provides an ergonomical and user friendly semi-automatic cable tie application tool capable of applying 18 to 120 lb. ties of any length. Referring now to the drawings, a semi-automatic cable tie application tool  10  in accordance with the present invention is shown in FIGS.  1 - 4 . Tool  10  includes a pistol-shaped housing  12  (a portion of which has been removed for clarity). In turn, housing  12  includes a barrel portion  50  and a grip portion  52 .  
         [0014]    As shown, tool  10  includes a pneumatic cylinder  14  located within the grip portion  52  of the tool. Cylinder  14  may be secured within the grip portion via a mounting block  16 , or in any other convenient fashion. As mentioned, the location of the cylinder within the grip portion of the tool creates a more balanced weight distribution, thereby improving the handling ease and ergonomics of the tool. A source of compressed air (not shown) is connected to cylinder  14  and is operated via a trigger-actuated valve (not shown). In this manner, actuation of trigger  54  by an operator causes compressed air (a typical pressure is 85 psi) to be directed to cylinder  16  (which may be a single acting, spring extended type design).  
         [0015]    As shown, the piston rod, i.e., piston rod  18 , extending from the cylinder is directed upwards towards the barrel of the tool along an axis P. As a result, piston rod  18  is angularly oriented with respect to actuating rod  20  (best shown in FIG. 4). Because the actuating rod must be actuated in a horizontal direction (in a direction extending along the length of the barrel defined by axis T), a pulley/cable system is employed to couple piston rod  18  to actuating rod  20 .  
         [0016]    More particularly, this cable system includes a cable  22  having a threaded connecting cap  24  secured at one end. Cap  24  is sized to be threaded onto the end of piston rod  18 . Of course, other means of connecting cap  24  to piston rod  18  are contemplated herein. A second connecting cap  26  is located at the other end of cable  22 . Connecting cap  26  is preferably connected to actuating rod  20  via a pin  56  which extends through an aperture  28  formed in cap  26  and through a corresponding aperture formed in actuating rod  20 . Again, cap  26  can be coupled to rod  20  in other manners. The cable/pulley assembly further includes a pair of pulleys  30 ,  32  which serve to redirect the movement of piston rod  18  (along axis P) into movement in-line with actuating rod  20  (along axis T). Particularly, pulley  30  is located directly in front of piston rod  18  to maintain alignment of the cable with the piston rod, while pulley  32  is located directly in-line with actuating rod  20 .  
         [0017]    It is contemplated herein that the present tool will utilize a polymer in frame construction (as opposed to prior art tools utilizing a 380-T6 aluminum construction). This polymer in frame construction can produce a weight saving of approximately 0.24 lbs. for a total weight of 0.96 lbs. (as compared to a comparable prior art tool formed of 380-T6 aluminum and weighing 1.2 lbs).  
         [0018]    The tensioning/cutoff mechanism of tool  10  is described in detail in commonly owned U.S. Pat. No. 5,915,425, the disclosure of which is incorporated herein by reference. In this regard, tool  10  preferably includes a nose portion  58  which provides angular adjustability to facilitate installation of cable ties in a variety of orientations with respect to the installer&#39;s workstation. Tool  10  also preferably includes an adjustable tensioning mechanism  60  which provides rapid adjustability of the tension setting level, allows the installer to readily view the tension setting level and provides an adjustable tension setting mechanism which resists damage due to impact/jarring of the tool and exposure to dirt and other environmental conditions. Finally, the tensioning/cutoff mechanism of tool  10  preferably reduces and/or eliminates recoil shock/vibration during severing of the cable tie tail from the installed cable tie.  
         [0019]    It will be appreciated that the present invention has been described herein with reference to certain preferred or exemplary embodiments. The preferred or exemplary embodiments described herein may be modified, changed, added to or deviated from without departing from the intent, spirit and scope of the present invention, and it is intended that all such additions, modifications, amendments and/or deviations be included within the scope of the following claims.