Abstract:
A clamp formed from a single block of resilient material, and preferably from nylon. A living hinge is formed that couples upper and lower jaws of the clamp. First and second arms extend rearwardly from the upper and lower jaws, respectively. A pivotally mounted camming member secured to one of the arms can be manually moved by a user from a first position, wherein it holds the jaws in tight, clamping engagement with an assembly position therebetween, to a second position in which the jaws can be opened. The clamp requires only a minimal degree of user effort during use, therefore making it particularly ideally suited for applications where a large plurality of the clamps must be used and repeatedly applied, then taken off from, one or more workpieces.

Description:
FIELD OF THE INVENTION  
         [0001]    This invention relates to clamps, and more particularly to a clamp having a living hinge, which can be quickly and easily placed in a clamped position with a minimal degree of physical effort by a user.  
         BACKGROUND OF THE INVENTION  
         [0002]    Clamps are used in a wide variety of applications. Typically, the clamp is comprised of a pair of jaws which are held pivotally to one another by a pivot pin or other like arrangement, and which includes a biasing spring which biases the jaws into a clamped position relative to each other. In some applications where a number of clamps need to be placed on a workpiece and then taken off, and this process repeated a number of times, the requirement of that the user has to use significant physical effort to overcome the spring force of the clamp in order to place the clamp on to the workpiece, and then again to take the clamp off of the workpiece, can lead to significant operative fatigue. This repeated process can also eventually slow down work tasks as workers become more and more fatigued from repeatedly applying and then removing a number of clamps. One such application involving the application of a large number of clamps is in the construction of commercial aircraft, and more particularly in the construction of interior panels used in commercial aircraft. Certain stages of construction of the interior panels involve adhering plastic trim pieces at the edges of interior panels. This assembly step requires the placement of a relatively large number of clamps onto the edges of the panels. This process has to be repeated a large plurality of times during the course of manufacture and assembly of the interior panels used in a commercial aircraft. Accordingly, a clamp which requires less physical effort by workers to use would be highly desirable in relieving worker fatigue and reducing the time needed to perform various assembly tasks.  
         SUMMARY OF THE INVENTION  
         [0003]    The present invention is directed to a clamp which can be more easily manually manipulated by a worker, and thus causes a lesser degree of user fatigue when using the clamp. The clamp of the present invention comprises a main body having a pair of jaws and a pair of arms portions. Each arm portion is operably associated with one of the jaws. A living hinge is formed at a portion of the main body to allow the jaws to be flexed toward or away from one another.  
           [0004]    At least one of the arms includes a camming member coupled thereto. In one preferred form the camming member is pivotally coupled to the arm. The camming member includes a graspable portion that may be easily grasped with a single hand of the user. The camming member can be moved by the user between a first position, wherein it prevents movement of the jaws relative to one another out of the clamped position, to a second position wherein the jaws can be urged away from one another. Moving the camming member from the first position to the second position requires only a very small degree of physical effort of the user, and typically considerably less effort than is required with many clamps employing coil-type biasing springs.  
           [0005]    When the camming member is placed in a first position, portions of it interfere with the arms to prevent the jaws from being opened relative to one another. Thus, in this position the jaws remain clamped to an external assembly placed therebetween. However, when the camming member is manually moved by a user into a second position, the arms are allowed to move relative to one another, which in turn allows the jaws to move away from the external assembly placed therebetween. Thus, the external assembly can be removed. The camming action provided by the camming member allows the jaws to be placed in a clamped position with only a very minimal degree of user force being needed to be exerted on the camming member. Thus, the present invention can be used repeatedly in applications where the use of a conventional clamp having a coil biasing spring to bias the jaws of the clamp toward one another could result in significant operator fatigue.  
           [0006]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0008]    [0008]FIG. 1 is a perspective view of a clamp in accordance with a preferred embodiment of the present invention being used to secure a plastic retainer component to an edge of an interior wall panel of a commercial aircraft;  
         [0009]    [0009]FIG. 2 is a front perspective view of the clamp of the present invention;  
         [0010]    [0010]FIG. 3 is a bottom plan view of just the main body of the clamp;  
         [0011]    [0011]FIG. 4 is a rear end view of the main body taken in accordance with directional line  4 - 4  in FIG. 3;  
         [0012]    [0012]FIG. 5 is a perspective view of the camming member;  
         [0013]    [0013]FIG. 6 is a side view of the clamp in its clamped position securing an external assembly between the jaws of the clamp;  
         [0014]    [0014]FIG. 7 is a side view of the clamp of FIG. 6 but with the clamp in the open position wherein the external assembly can be removed from between the jaws;  
         [0015]    [0015]FIG. 8 is a side view of a clamp in accordance with an alternative preferred embodiment of the present invention, in the unclamped position; and  
         [0016]    [0016]FIG. 9 is a view of the clamp of FIG. 8 but with the clamp in a clamped position.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.  
         [0018]    Referring to FIG. 1, there is shown a clamp  10  in accordance with a preferred embodiment of the present invention. The clamp  10  is shown secured to a plastic retainer member  12  positioned against an interior panel  14  of a commercial aircraft. It will be appreciated immediately, however, that the clamp  10  is not limited to applications involving the manufacture of commercial aircraft, but will find utility in a wide variety of other applications where it is necessary to be able to quickly and easily clamp two or more components together with a short, convenient movement that does not require significant operator effort, and which does not result in significant operator fatigue when the clamp must be used repeatedly over a given period of time. For purposes of discussion, retainer member  12  and panel  14  will be cooperatively referred to as external assembly  16 .  
         [0019]    With specific reference to FIGS. 1 and 2, the clamp  10  comprises a main body  18  comprised of a first jaw  20 , a second jaw  22 , a first arm  24 , a second arm  26  and a camming member  28 . First arm  24  is formed generally coextensively with first jaw  20 , while second arm  26  is formed generally coextensively with second jaw  22 . Jaws  20  and  22  are separated from one another by a living hinge  30 . In one preferred form the entire main body  18  is formed from a single piece of suitably resilient material, and more preferably from TY-6 nylon. The thickness of the living hinge  30  may vary considerably, but in one preferred form is preferably between about 0.06 inch-0.08 inch (1.524 mm-2.032 mm). Other suitable material for the main body  18  may comprise spring steel, or virtually any material having the necessary resilient characteristics. The thickness of the hinge  30  will also be influenced by the specific material used for the main body portion  18 . It has further been found that cutting the main body portion  18  from a single block of material through a well known water jet cutting process appears to yield even better results, and more consistent operating characteristics (i.e., more consistent spring force of the living hinge  30 ), than molding the main body portion  18  through an injection molding process.  
         [0020]    With further reference to FIG. 2, the camming member  28  comprises a manually graspable portion  32  and a camming portion  34 . With brief reference to FIG. 3, the second arm  26  includes a slot  36  formed therein which effectively forms a “yoke” in a rear portion  38  of the second arm  26 . A pair of bores  40  and  42  (FIG. 3) are formed in alignment with one another through the rear portion  38 . The width of the slot  36  is sufficient to accommodate the thickness of the camming member  28 .  
         [0021]    With further reference to FIGS. 2-5, the camming member  28  further includes an aperture  44  (FIG. 5). A pivot pin  46  (FIG. 2) is inserted through the apertures  40  and  42  (FIG. 3 in order to pivotally couple the camming member  28  to the second arm  26 . The camming member  28  may be made from a wide variety of suitably rigid materials such as aluminum, steel or plastic, but in one preferred form is comprised of acetyl, which is a semi-crystalline material having a low coefficient of friction and excellent wear properties.  
         [0022]    With further reference to FIG. 2, it will be appreciated that the jaws  20  and  22 , in combination with the living hinge  30 , cooperatively form an opening  48 . As will be appreciated, opening  48  could be formed to more precisely match (or accommodate) a specific assembly that the clamp may be used frequently (or exclusively) with. Additionally, the overall height of the living hinge  30 , as well as its thickness, influences the amount of force that the jaws  20  and  22  will exert on the external assembly  16  when the clamp  10  is in its clamped position. Furthermore, the flexibility of the arms  24  and  26  is also an important factor, as well as the thickness of the arms  24  and  26 , in influencing the degree of clamping force provided by the clamp  10 . As a result, it will be appreciated that the shape and thickness of the assembly with which the clamp  10  will be used with will, in many applications, also be an important consideration that will influence the design of the clamp  10 . Also, it will be appreciated that the main body  18  is preferably formed such that the jaws  20  and  22 , while in their “rest” positions, are exerting a desired clamping force on the external assembly  16 , thus obviating the need for a biasing spring or like element to be included to generate the needed clamping force.  
         [0023]    Referring now to FIGS. 6 and 7, the operation of the clamp  10  will be described. In FIG. 6, the clamp is shown in its clamped or closed position with the external assembly  16  clamped between the jaws  20  and  22 . Camming surface  35  of the camming portion  34  of the camming member  28  engages an undersurface  25  of the arm  24  to hold the jaws  20  and  22  in the clamped position as shown. In this regard, a well known over center action may be employed by forming the pivot aperture  44  (FIG. 5) on the camming member  28  at a precise position relative to the camming surface  35  such that the reactive forces applied by the arms  24  and  26  will also tend to hold the camming member  28  in the position shown in FIG. 6.  
         [0024]    When the external assembly  16  needs to be removed, the camming member  28  is rotated clockwise in the drawing of FIG. 7 into the fully open (i.e., unclamped) position shown in FIG. 7. A small degree of pressure can be applied in accordance with arrows  50  and  52  on the arms  24  and  26 , respectively, to spread the jaws  20  and  22  apart from one another. The external assembly  16  can then be removed from between the jaws  20  and  22 .  
         [0025]    Referring now to FIGS. 8 and 9, a clamp  100  in accordance with an alternative preferred embodiment of the present invention is shown. The clamp  100  is similar to clamp  10  and, and components common to clamp  10  are designated by reference numerals increased by  100  over those used in describing clamp  10 .  
         [0026]    The clamp  100  includes a main body portion  118  having jaws  120  and  122  and arms  124  and  126 , respectively. Living hinge  130  provides the needed biasing force to hold the jaws  120  and  122  in the clamped position. In addition, a biasing spring  154  has a first end  156  held by a stop element  158 . The stop element  158  is illustrated as a threaded screw, but it will be appreciated that a pin, protrusion formed on the main body  118 , or any other suitable means may just as readily be used to hold the first end  156  of the spring  154 . A second end  160  of the spring  154  extends through a bore  162  in the main body  118  to place the spring under compression. This compression tends to urge the jaws  120  and  122  apart into the position shown in FIG. 8 when the clamp  100  is in its unclamped or “open” orientation, and effectively works against to overcome the biasing tendency of the living hinge  130  to close the jaws  120 ,  122 . A stop washer  164  is held against the arm  126  by a fastening element  166 , for example a threaded screw or other suitable fastening element, to provide a positive stop for the camming member  128 . The camming member  128  is pivotally held to the lower arm  126  by a pivot pin  146 .  
         [0027]    In operation, the spring  154  holds the jaws  120  and  122  apart as shown in FIG. 8 to allow the jaws  120 , 122  of the clamp  100  to be orientated over the external assembly  16 . Thus, the user is not required to exert any force to hold the jaws  120 ,  122  apart while the external assembly  16  is positioned therebetween. Once the external assembly  16  is positioned the between the jaws  120 , 122 , the user merely urges the camming member  128  in accordance with directional arrow  168 . This causes the camming surface  135  to be urged into contact with the upper arm  124  to thus lock the jaws  120 , 122  in the clamped orientation (FIG. 9). The stop washer  164  provides a positive stop for the camming member  128 .  
         [0028]    A principal advantage of the clamp  100  is that no operator effort is required to hold the clamp in the open position while the clamp is being orientated relative to the external assembly  16 . Another advantage is that only a small degree of force is required to move the camming member  128  from the position shown in FIG. 8 to that shown in FIG. 9. Depending on the overall dimensions of the clamp  100 , it is possible to move the clamp from the position shown in FIG. 8 to that shown in FIG. 9 with only a single hand while holding the clamp between the thumb and forefinger. The shape of the camming surface  135  can also be made with a sufficient curvature to impart an over center action to assist in urging the camming member  128  into the fully engaged position of FIG. 9.  
         [0029]    The present invention thus forms a clamp which can be quickly and easily applied, and reapplied a large plurality of times, during the course of a work project, without causing significant user fatigue. The clamp is relatively inexpensive to construct, durable, and can be moved between its clamped and unclamped states very quickly with only a small degree of user effort.  
         [0030]    The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.