Trigger mechanism for crossbow

Abstract

The invention relates to the technical field of athletic equipment, and specifically to a trigger mechanism for crossbow. It comprises a bracket, a trigger system assembled on the bracket and a bow string; said string locking safety device comprises a sear, a sear connecting rod, a sear toggle lever, a trigger connecting rod and a safety button. In the whole attaching string and firing process of the trigger mechanism described in the invention, each hinged point is in pivoting friction contact in a full cycle manner, the contact surface of each hinged point does not change, and the pressure ratio of each contact surface doesn't increase significantly, and an increase in pressure ratio of the contact surface will not occur due to the friction contact surface decrease along with firing; there is no accelerated wear and tear of various moving parts and the service life is long.

1 . A trigger mechanism for crossbow, comprising a bracket ( 1 ), a trigger system assembled on the bracket ( 1 ) and a bow string ( 23 ); said trigger system comprises a trigger ( 15 ) and a string locking safety device; said string locking safety device comprises a sear ( 4 ), a sear connecting rod ( 9 ), a sear toggle lever ( 8 ), a trigger connecting rod ( 10 ) and a safety button ( 13 ); the middle part of the sear ( 4 ) is hingedly connected to the bracket ( 1 ), and its front part is provided with a string groove with opening downward, and its tail end is hingedly connected to the top part of the sear connecting rod ( 9 ); the bottom part of said sear connecting rod ( 9 ) is hingedly connected to the top part of the sear toggle lever ( 8 ); the middle part of said trigger connecting rod ( 10 ) and the middle part of said sear toggle lever ( 8 ) are hingedly assembled on the bracket ( 1 ) by the toggle lever pin ( 6 ); the bottom front side of said trigger connecting rod ( 10 ) is connected with the trigger reset spring ( 21 ), and the top part of said trigger reset spring ( 21 ) is connected to the bracket ( 1 ); the top end of said trigger ( 15 ) is fixedly connected to the bottom end of said trigger connecting rod ( 10 ); said safety button ( 13 ) is assembled at the tail end of the bracket ( 1 ) and is capable of moving back and forth along the bracket ( 1 ). 
     
     
         2 . The trigger mechanism for crossbow of  claim 1  wherein a limiting pin ( 19 ) is fixed to the bottom end of said sear toggle lever ( 8 ), and a toggle lever reset spring ( 16 ) is provided underneath said limiting pin ( 19 ); said toggle lever reset spring ( 16 ) is mounted on the toggle lever reset spring pin ( 25 ) on the rear side of the upper section of the trigger ( 15 ). 
     
     
         3 . The trigger mechanism for crossbow of  claim 2  wherein on the upper rear side of said sear ( 4 ) is provided with a sear reset compression spring ( 22 ); said bracket ( 1 ) is mounted with an adjusting bolt ( 12 ) for adjusting the pressure on the sear reset compression spring ( 22 ). 
     
     
         4 . The trigger mechanism for crossbow of  claim 3  wherein a buffer pad ( 17 ) is fixed on the front upper part of said sear ( 4 ).