Self Locking Racket Stringing Machine Tensioner

Abstract

An automatically braking tensioner for a racket stringing machine is disclosed. The tensioner comprises a tensioner housing, a drum connected to the tensioner housing, a string gripper connected to the drum, a disk brake having an axle extending from an axis of the disc brake, a lever disposed in the tensioner housing, and a brake lever disposed in the tensioner housing. The disk brake is connected to a stringing machine body and is rotably stationary relative to the stringing machine body. As the tensioner is rotated about the disk brake, the brake lever is engaged with the disk brake when the tensioning force is equal to a desired force which can be established my means of a compression spring. In some embodiments the tension can be altered by varying the tension or position of the spring.

1 ) A tensioner arm for a racket stringing machine comprising
 a) a tensioner housing;   b) a lever disposed in said tensioner housing;   c) a drum connected to said lever;   d) a string gripper connected to said drum;   e) a compression spring disposed between said lever and an internal portion of said tensioner housing.   
     
     
         2 ) The tensioner arm as in  claim 1  further comprising a slidable spring assembly
 a) wherein said tensioner housing has an elongated slot in one side; 
 b) wherein said compression spring is disposed in said slidable spring assembly; 
 c) wherein a portion of said slidable spring assembly extends through said elongated slot. 
 
     
     
         3 ) The tensioner arm as in  claim 2  wherein said slidable spring assembly further comprises
 a) a spring housing; and 
 b) a spring support pad disposed at an end of said compression spring and wherein said spring support pad is disposed adjacent to said lever. 
 
     
     
         4 ) The tensioner as in  claim 1  further comprising
 a) a disk brake having an axle extending from an axis of said disc brake;
 i) wherein said disk brake is connected to a stringing machine body and is rotably stationary relative to said stringing machine body; 
 ii) wherein said disk brake has a lip disposed laterally from said disk brake; 
 
 b) a brake lever disposed in said tensioner housing;
 i) wherein said brake lever has a first end and a second end, said first end having a channel disposed laterally into said brake lever; 
 
 c) wherein said lever has a first end and a second end, said first end having an aperture; 
 d) wherein said axel of said disk brake is disposed through said aperture of said lever; and 
 e) wherein said lip of said disk brake is disposed within said channel of said brake lever. 
 
     
     
         5 ) The tensioner as in  claim 4  further comprising a cam
 a) wherein said cam is connected to said lever; 
 b) wherein said cam has a varying diameter about said cam; 
 c) wherein an external perimeter of said cam is adjacent to said second end of said brake lever; 
 d) wherein when said cam rotates about a cam axis, said external perimeter of said cam displaces said second end of said brake lever. 
 
     
     
         6 ) The tensioner as in  claim 5  further comprising an axial spring having a first end connected to said lever and a second end connected to said cam. 
     
     
         7 ) The tensioner as in  claim 6  further comprising a stop connected to said tensioner housing wherein said stop is disposed within a notch in said cam, preventing said cam from rotating about said cam axis when said stop is disposed within said notch. 
     
     
         8 ) The tensioner as in  claim 7  further comprising a pin having a first end connected to said cam and a second end disposed adjacent to said first end of said brake lever. 
     
     
         9 ) An automatically braking tensioner for a racket stringing machine comprising
 a) a tensioner housing;   b) a drum;   c) a string gripper connected to said drum;   d) a disk brake having an axle extending from an axis of said disc brake;
 i) wherein said disk brake is connected to a stringing machine body and is rotably stationary relative to said stringing machine body; 
 ii) wherein said disk brake has a lip disposed laterally from said disk brake; 
 iii) wherein said disk brake is disposed within an internal cavity of said drum; 
   e) a lever disposed in said tensioner housing;
 i) wherein said lever has a first end and a second end, said first end having an aperture; 
 ii) wherein said axel of said disk brake is disposed through said aperture; 
   f) a brake lever disposed in said tensioner housing;
 i) wherein said brake lever has a first end and a second end, said first end having a channel disposed laterally into said brake lever; 
   g) wherein said lip of said disk brake is disposed within said channel of said brake lever.   
     
     
         10 ) The tensioner as in  claim 9  further comprising a cam
 a) wherein said cam is connected to said lever; 
 b) wherein said cam has a varying diameter about said cam; 
 c) wherein an external perimeter of said cam is adjacent to said second end of said brake lever; 
 d) wherein when said cam rotates about a cam axis, said external perimeter of said cam displaces said second end of said brake lever. 
 
     
     
         11 ) The tensioner as in  claim 10  further comprising an axial spring having a first end connected to said lever and a second end connected to said cam. 
     
     
         12 ) The tensioner as in  claim 11  further comprising a stop connected to said tensioner housing wherein said stop is disposed within a notch in said cam, preventing said cam from rotating about said cam axis when said stop is disposed within said notch. 
     
     
         13 ) The tensioner as in  claim 12  further comprising a pin having a first end connected to said cam and a second end disposed adjacent to said first end of said brake lever. 
     
     
         14 ) The tensioner as in  claim 13  further comprising
 a) a slidable spring assembly; 
 b) a slot disposed in said tensioner housing; 
 c) wherein said slidable spring assembly is configured to slide along a length of said lever; 
 d) wherein a portion of said slidable spring assembly extends through said slot. 
 
     
     
         15 ) The tensioner as in  claim 14  wherein said slidable spring assembly further comprises
 a) a spring housing; 
 b) a compression spring disposed within said spring housing; 
 c) a spring support pad disposed at an end of said spring and wherein said spring support pad is disposed adjacent to said lever. 
 
     
     
         16 ) The tensioner as in  claim 15  wherein said cam further comprises a brake release extending from said cam and disposed through an aperture in said tensioner housing. 
     
     
         17 ) A racket stringing machine comprising
 a) a machine base;   b) a rotational plate base attached to said machine base;   c) a self-locking tensioner attached to said machine base, wherein said self-locking tensioner further comprises
 i) a tensioner housing; 
 ii) a drum; 
 iii) a string gripper connected to said drum; 
 iv) a disk brake having an axle extending from an axis of said disc brake;
 (1) wherein said disk brake is connected to a stringing machine body and is rotably stationary relative to said stringing machine body; 
 (2) wherein said disk brake has a lip disposed laterally from said disk brake; 
 (3) wherein said disk brake is disposed in an internal cavity of said drum; 
 
 v) a lever disposed in said tensioner housing;
 (1) wherein said lever has a first end and a second end, said first end having an aperture; 
 (2) wherein said axel of said disk brake is disposed through said aperture; 
 
 vi) a brake lever disposed in said tensioner housing;
 (1) wherein said brake lever has a first end and a second end, said first end having a channel disposed laterally into said brake lever; 
 
 vii) wherein said lip of said disk brake is disposed within said channel of said brake lever. 
   
     
     
         18 ) The racket stringing machine as in  claim 17  wherein said self-locking tensioner further comprises a cam
 a) wherein said cam is connected to said lever; 
 b) wherein said cam has a varying diameter about said cam; 
 c) wherein an external perimeter of said cam is adjacent to said second end of said brake lever; 
 d) wherein when said cam rotates about a cam axis, said external perimeter of said cam displaces said second end of said brake lever. 
 
     
     
         19 ) The racket stringing machine as in  claim 17  wherein said self-locking tensioner further comprises an axial spring having a first end connected to said lever and a second end connected to said cam. 
     
     
         20 ) The racket stringing machine as in  claim 18  wherein said self-locking tensioner further comprises a stop connected to said tensioner housing wherein said stop is disposed within a notch in said cam, preventing said cam from rotating about said cam axis when said stop is disposed within said notch.