Patent Publication Number: US-8985091-B2

Title: Double linkage triggering system used for crossbow

Description:
PRIORITY CLAINM AND RELATED APPLICATIONS 
     This application claims the benefit of priority under 35 U.S.C. Section 119 to Chinese Patent Application Serial No. 201220733421.1, filed Dec. 28, 2012, which application is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The Invention relates to a double linkage trigger system used on crossbows in the field of crossbow manufacture. 
     TECHNICAL BACKGROUND 
     A crossbow is a kind of sports facilities with extremely strong firing force, of which the firing mechanism includes mainly a trigger system and bowstring and wherein the trigger system is the crucial control device when shooting. Accordingly, the security, the operability and the maintainability of the triggering system might directly affect the efficiency and the safety of the crossbow. The present trigger system adopted in the market is configured as a whole body and it is exceedingly difficult to be assembled or disassembled. Consequently the trigger system is very hard to be maintained and well-used. In addition, a safety device on the crossbow itself is mainly used in order to prevent the arrow from being launched by mistake. However, the effective protection is deficient for the trigger system. Once the safety device on the crossbow itself is broken down or operated by mistake, it will cause error shooting/launching of the arrow and then reduce the safety when using the crossbow. 
     On the other hand, the arrow always drops off easily due to the restriction of the operating angle and the faulty operation when using the crossbow. Furthermore, even if the arrow is dropped off or is not installed correctly, the shooting of the crossbow is still capable of being performed and it leads to empty shooting accordingly. Although the empty shooting is not harmful to the crossbow body and the user, it will reduce greatly the using efficiency. 
     SUMMARY 
     The invention provides a double linkage triggering system used on crossbows for obviating one or more problems mentioned above in the prior art. The invention discloses the following technical features. The double linkage triggering system used on a crossbow includes a main body, which is composed of a trigger unit  1  and a shooting unit  2 , wherein the trigger unit  1  is capable of being contacted with the shooting unit  2 . The trigger unit  1  comprises a bracket body  3 , a trigger block  4 , a hammer  5 , a trigger power-adjusting bolt  6 , a triggering mechanism and a trigger-safety device. The hammer  5  is hinge connected to the bracket body  3  and is capable of being contacted with the triggering mechanism. The trigger block  4  is hinge connected to the bracket body  3  and each end of the trigger block  4  is respectively capable of being limited by the hammer  5  and the trigger power-adjusting bolt  6 . The triggering mechanism and trigger power-adjusting bolt  6  are both inserted into the bracket body  3 . The trigger-safety device includes a rotating block  7  and a shifting block  8 . The rotating block  7  is connected with the shifting block  8  by a bolt and is hinge connected to the bracket body  3 , wherein, the rotating block  7  is capable of being contacted with the hammer  5 , and the shifting block  8  is arranged outside of the bracket body  3 . The shooting unit  2  consists of a sight stand  9 , a guide device  10 , a pressure plate  11 , a rotary latch  12 , a roof plate  13 , a latching plate  14 , a returning device, and an anti-empty shooting mechanism. The returning device is inserted into the roof plate  13  and is capable of being squeezed or impacted with the latching plate  14 . Furthermore, the roof plate  13  is hinge connected to the latching plate  14  and a positioning groove  15  is formed on the front end of the latching plate  14 . Both of the sight stand  9  and the rotary latch  12  are hinge connected to the roof plate  13 , and wherein the rotary latch  12  is located at the interior of the sight stand  9 . Consequently two contacting surfaces  16  are formed between the rotary latch  12  and the roof plate  13 , between which the angle at the range of 120° to 160° can be created. A guide device  10  and a pressure plate  11  are further provided on the sight stand  9 . 
     The anti-empty shooting mechanism is composed of an arrow placing device  17 , a stopblock  18  and a positioning spring  19 . An arrow slot  20  is formed on the front end of the upper surface of the arrow placing device  17 . A sliding groove  21  is located on the middle section of the arrow placing device  17 . A mounting block  22  is equipped on the distal end of the arrow placing device  17  and also, a positioning pin  23  is formed on the surface of the distal end of it. Here, the positioning pin  23  is surrounded by the positioning spring  19  and is capable of being contacted with the roof plate  13 . The mounting block  22  is inserted into the roof plate  13 . The stopblock  18 , with a side face having a fixing groove  24  and a lower surface configured by a wedge-shaped sliding surface  25  and horizontal fixing surface  26 , is hinge connected to the rotary latch  12 . 
     The triggering mechanism includes a triggering pin  27  and a triggering spring  28 , wherein the triggering pin  27  is surrounded by the triggering spring  28 . 
     The returning device consists of a returning pin  29  and a returning spring  30 , wherein the returning pin  29  is surrounded by the returning spring  30 . 
     The invention brings the following technical effects: 
     (1) The separate-style triggering system is disclosed in the invention, which is both simple and elegant and easy to be assembled or disassembled. The efficiency of the trigger is increased greatly and also the maintenance of the trigger becomes convenient, by which therefore, the reliability and the working life of the crossbow can be improved.
 
(2) A protecting device is provided for the triggering device in the triggering system. The shooting of the arrow due to the faulty operation is capable of being prevented accordingly. It will also improve the reliability and the security of using the triggering system.
 
(3) An anti-empty shooting mechanism is further provided in the triggering system, which increases working efficiency of the crossbow.
 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       The present disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the present disclosure, and wherein: 
         FIG. 1  is a structure diagram of the double linkage triggering system used on crossbows disclosed in the invention. 
     
    
    
     DETAILED DESCRIPTION 
     As shown in  FIG. 1 , the double linkage triggering system used on a crossbow includes a main body, which is composed of a trigger unit  1  and a shooting unit  2 , wherein the trigger unit  1  is capable of being contacted with the shooting unit  2 . The trigger unit  1  comprises a bracket body  3 , a trigger block  4 , a hammer  5 , a trigger power-adjusting bolt  6 , a triggering mechanism and a trigger-safety device. The hammer  5  is hinge connected to the bracket body  3  and is capable of being contacted with the triggering mechanism The trigger block  4  is hinge connected to the bracket body  3  and each end of the trigger block  4  is respectively capable of being limited by the hammer  5  and the trigger power-adjusting bolt  6 . Further, the triggering mechanism and trigger power-adjusting bolt  6  are both inserted into the bracket body  3 . The trigger-safety device includes a rotating block  7  and a shifting block  8 . The rotating block  7  is connected with the shifting block  8  by a bolt and is hinge connected to the bracket body  3 , wherein, the rotating block  7  is capable of being counterbalanced to the hammer  5 , and the shifting block  8  is arranged outside of the bracket body  3 . 
     Besides, the shooting unit  2  consists of a sight stand  9 , a guide device  10 , a pressure plate  11 , a rotary latch  12 , a roof plate  13 , a latching plate  14 , a returning device, and an anti-empty shooting mechanism. The returning device is inserted into the roof plate  13  and is capable of being squeezed with the latching plate  14 . Furthermore, the roof plate  13  is hinge connected to the latching plate  14  and a positioning groove  15  is formed on the front end of the latching plate  14 . Both of the sight stand  9  and the rotary latch  12  are hinge connected to the roof plate  13 , and wherein the rotary latch  12  is located at the interior of the sight stand  9 . Consequently two contacting surfaces  16  are formed between the rotary latch  12  and the roof plate  13 , between which the angle at the range of 120° to 160° can be created. Preferably, a guide device  10  and a pressure plate  11  are provided on the sight stand  9 . 
     Further, the anti-empty shooting mechanism is composed of an arrow placing device  17 , a stopblock  18  and a positioning spring  19 . An arrow slot  20  is formed on the front end of the upper surface of the arrow placing device  17 . A sliding groove  21  is located on the middle section of the arrow placing device  17 . A mounting block  22  is equipped on the distal end of the arrow placing device  17  and also, a positioning pin  23  is formed on the surface of the distal end of it. Here, the positioning pin  23  is surrounded by the positioning spring  19  and is capable of being squeezed with the roof plate  13 . The mounting block  22  is inserted into the roof plate  13 . The stopblock  18 , with a side face having a fixing groove  24  and a lower surface configured by a wedge-shaped sliding surface  25  and horizontal fixing surface  26 , is hinge connected to the rotary latch  12 . The triggering mechanism includes a triggering pin  27  and a triggering spring  28 , wherein the triggering pin  27  is surrounded by the triggering spring  28 . The returning device consists of a returning pin  29  and a returning spring  30 , wherein the returning pin  29  is surrounded by the returning spring  30 . 
     
       
         
           
               
               
               
               
               
               
             
               
                   
               
             
            
               
                  1. 
                 trigger unit 
                  2. 
                 shooting unit 
                  3. 
                 bracket body 
               
               
                  4. 
                 trigger block 
                  5. 
                 hammer 
                  6.  
                 trigger power-adjusting bolt 
               
               
                  7. 
                 rotating block 
                  8.  
                 shifting block 
                  9. 
                 sight stand 
               
               
                 10. 
                 guide device 
                 11. 
                 pressure plate 
                 12.  
                 rotary latch 
               
               
                 13.  
                 roof plate 
                 14. 
                 latching plate 
                 15.  
                 positioning groove 
               
               
                 16. 
                 contacting surface 
                 17.  
                 arrow placing device 
                 18. 
                 stopblock 
               
               
                 19. 
                 positioning spring 
                 20. 
                 arrow slot 
                 21. 
                 sliding groove 
               
               
                 22. 
                 mounting block 
                 23. 
                 positioning pin 
                 24. 
                 fixing groove 
               
               
                 25. 
                 wedge-shaped sliding surface 
                 26.  
                 horizontal fixing surface 
                 27. 
                 triggering pin 
               
               
                 28.  
                 triggering spring 
                 29.  
                 returning pin 
                 30. 
                 returning spring