Abstract:
A switching assembly that operatively cooperates with the triggering mechanism of a firearm, such as a rocket launcher, is disclosed. The switching assembly allows for an adjustable trigger linear travel of about 0.4″ within an accuracy of 0.01 inches, while at the same time prevents any over-travel of the switch activator from damaging a depressible switch that is operatively interconnected to firing of the rocket from the launcher.

Description:
ORIGIN OF THE INVENTION 
     The invention described herein was made in the performance of official duties by an employee of the Department of the Navy and may be manufactured, used, licensed by or for the Government for any governmental purposes without the payment of any royalty thereon or therefor. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to firearm technology and, more particularly, to an assembly for controlling the triggering action of a firearm, such as rocket launchers. 
     BACKGROUND OF THE INVENTION 
     Triggering mechanisms for firearms, such as a rocket launcher, are well known, and need to provide precision activation, while at the same time provide repeatable and reliable operation. One of the parameters of a triggering mechanism that needs to be taken into account is the amount of travel that the trigger encounters during its usage in activating the firearm. For firearms, such as a rocket launcher, it is desirable that the amount of travel be limited to 0.4 or less inches of linear travel. 
     Triggering mechanisms for firearms, such as a rocket launcher, typically activate a depressible switch, which, in turn, activates the associated elements for the initiation and, then, completion of the firing of the rocket from the associated launcher. A triggering mechanism that experiences overshoot, may damage the depressible switch which, in turn, may negate the operational readiness of the associated firearm. It is desired that means be provided for a triggering mechanism that prevents the damage commonly caused by overshoot of the trigger mechanism. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is a primary object of the present invention to provide for a triggering mechanism in which the movement of the trigger is limited to 0.4″ of linear travel and is adjustable to within an accuracy of about 0.01″. 
     It is a further object of the present invention to provide means that prevents any damage to a depressible switch that may occur from the over-travelling of an associated trigger switch. 
     In accordance with these and other objects, the invention provides an assembly interconnected to a trigger mechanism of a firearm that controls the triggering action thereof. The assembly comprises a housing, a sliding actuator, first and second yielding means, a rod, a block mated to the housing, and a depressible switch. The sliding actuator has an interior and is lodged in the housing and has first and second ends with an extension extending outward from the first end. The first yielding means has a first predetermined stiffness and is lodged in the housing and located around the first end of the sliding actuator. The second yielding means has a second predetermined stiffness which is less than the first stiffness and is lodged in the housing and located around the second end of the sliding actuator. The rod has at least first and second sections having respective diameters to pass through the interior of the siding actuator and to come in contact with the first yielding means. The block is located adjacent the extension of the sliding actuator, whereas the depressible switch is located on the block and in alignment with the extension of the sliding actuator. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing objects and advantages of the present invention will become more fully understood from the following detailed description and reference to the appended drawings wherein: 
     FIG. 1 is an overall view of the trigger mechanism of the present invention shown mounted on a typical rocket launcher assembly. 
     FIG. 2 illustrates the assembly of the present invention for a trigger mechanism and is partially cut-away so as to more clearly show the arrangement of the associated elements thereof. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings, wherein the same reference number indicates the same element throughout, there is shown in FIG. 1 an overall view of a typical launcher/spotter rifle assembly designated generally by the reference number  10 . The rocket launcher/spotter rifle assembly  10  has a handle  12  that is used to operate a trigger  14  whose triggering action is controlled by the assembly  100  (shown in phantom) of the present invention which may be further described with reference to FIG.  2 . 
     The assembly  100  comprises a housing  102  and a switch activator  104 . The switch activator  104  is lodged in the housing  102  and has first and second ends  106  and  108  with an extension  110  extending outward from the first end  108 . The switch activator  104  also has an interior  112  that completely extends therethrough. 
     The assembly  100  further comprises first and second yielding means  114  and  116  respectively located adjacent the first end  106  and the second end  108 . The first yielding means  114  has a first predetermined stiffness and the second yielding means  116  has a second predetermined stiffness which is less than the first stiffness. The spring constant for yielding means  116  may be approximately 15 lb/in. The spring constant of yielding means  114  may be approximately 100 lb/in. 
     The assembly  100  further comprises a rod  118  having at least first and second sections  120  and  122  with the first section  120  having a diameter that allows it to pass through the interior  112  of the sliding actuator  104 . The second section  122  has a leading edge  122 A that comes into contact with the first yielding means  114 . The second section  122  of rod  118  enters and snugly occupies an opening  124  of the housing  102 . 
     The assembly  100  further comprises a block  126  mated to the housing  102  by appropriate means. Screws  128  and  130  hold switch  132  to block  126 . Block  126  is mated to housing  102  by the geometry of the block and housing (ie: keys and keyways cut into parts) and screw  140 . The block  126  has attached thereto by appropriate means (not shown) a depressible switch assembly  132  which may have an arm  134  that is located in alignment with the extension  110  of the sliding actuator  104 . 
     The block  126  is preferably slidably adjusted by adjustment means  136  shown in the upper portion of block  126  as viewed in FIG.  2 . The adjustment means  136  comprises a threaded opening  138  of the block  126  and a screw  140  having a head  142  and threads  140 A which are complementary to the internal threads on the opening  138  of the block  126 . The head  142  preferably has a groove  144  into which is lodged a spring pin  146 . 
     The housing  102  has a hollow comprising a sequentially arranged first, second and third compartments that respectively provide for the lodging therein of the first yielding means  114 , first and second ends  106  and  108  of the switch actuator  104  as well as the extension  110  of the slidable actuator  104 , and the second yielding means  116 . The third compartment that lodges the second yielding means  118  further comprises an opening in the third compartment and which is dimensioned to accept a set screw  148  which, in turn, is dimensioned to pass through the predetermined opening of the second yielding means  116 . The set screw  148  is adjustable by an opening (not shown) in the block  102  so as to come into contact with the second end  108  of the switch actuator  104 . The set screw serves as a stop for the sliding actuator  104 . The set screw  148  comes into contact with the second end  108  of the sliding actuator  104 . 
     The first and second yielding means  114  and  116  are dimensioned so as to respectively operate within the first and second compartments of the housing  102 . The first yielding means  114  has a predetermined opening that is sufficient to accept the first section  120  of the rod  118 , whereas the second yielding means  116  has a second predetermined opening that is sufficient to accept the set screw  148 . 
     The switch actuator  104  is dimensioned so that its first and second ends  106  and  108  completely occupy the second compartment of housing  102 . The interior  112  of the sliding actuator  104  has a linear length which is sufficient to accept the complete length of the section  120  of the rod  118  when the first yielding means  114  is in its completely compressed state. 
     The rod  118  is selected so that its first section  120  has a diameter which is dimensioned so as to pass through the predetermined opening of the first yielding means  114 . The second section  122  of rod  118  is dimensioned, in particular, to have a leading edge  122 A that engages the first yielding means  114 . The rod  118  preferably has a third section  150  that has a diameter similar to that of the first section  120  and has a length sufficient to interconnect to a cam which is tied to the launcher trigger mechanism  14  of FIG.  1 . 
     Operation of the Switch Assembly 
     With reference to FIG. 2, in operation, the rod  118  is pushed in the direction  152  by way of the cam movement of the launcher trigger  14 . The movement of the rod  118  in direction  152  causes the leading edge  122 A to intercept the first yielding means  114  which, in turn, pushes against the first end  106  of the sliding activator  104  causing the first end  106  and the second end  108  to move in a direction  154 , while also causing the extension  110  to move in a direction  156  shown in FIG.  2 . 
     The switch activator  104  and the rod  118  move in unision due to the high stiffness of the first yielding means  114  which serves as an override spring. The switch activator  104 , in particular, its extension  110  intercepts the arm  134  of the switch assembly  132  which, in turn, causes the triggering action of the switch assembly  132 . After such triggering action, the second end  108  of the switch activator  104  intercepts the set screw  148  which prevents the switch activator  104 , in particular, its outward extension from crushing the switch  132 . The rod  118  however, is allowed to continue moving through the interior  112  of the switch activator  104  and it compresses the second yielding means  114 . Screw  148  prevents end  108  from compressing  116 , but only after switch has been activated. When the launcher trigger  14  is released, the switch activator  104 , the first yielding means  114  serving as an override spring, and the switch rod  118  are returned to their original home positions by the resiliency of the second yielding means  116  serving as a recoil spring. 
     The switch assembly  132  can be adjusted to trigger within a range of about 0.4″ within an accuracy of about 0.01 inches of horizontal travel by means of the adjustment screw  140  and the set screw  148 . The adjustment screw  140  preferably fits through a hole  158  in the block  126  and is threaded into the opening  138  of the block  126 . The pin  146  captures the adjustment screw  142  while allowing the adjustment screw  142  to turn about its axis which, in turn, allows the switch assembly  132  carried by the block  126  to be moved back and forth until the switch assembly  132  is properly adjusted in position relative to extension  110  and within a range of 0.012-0.04 for the separation between the switch activator  104  and the arm  134  of the switch assembly  132 . The set screw  148  is adjusted such that the switch tab  104  moves only enough to trigger the switch assembly  132 . 
     It should now be appreciated that the practice of the present invention provides for a switch assembly that allows for an adjustable linear travel of its associated trigger mechanism of about 0.41″ and such adjustment is within an accuracy of about 0.01 inches. Further, it should be appreciated that the practice of the present invention prevents any damage to the switch assembly of the launcher mechanism from any over-travel of the trigger mechanism. 
     Although the invention has been described relative to a specific embodiments thereof, there are numerous variations and modifications that will be readily apparent to those skilled in the art in light of the above teachings. It is, therefore, to be understood that, within the scope of the appended claims, the invention may be practiced other than as specifically described.