Tightening structure for locking and nut and washer for the tightening structure

Abstract

A tightening structure for locking, comprising a nut, a bolt, and a hole for passing the bolt therethrough, wherein, to more firm the locking, a recessed part symmetrical with respect to an axis and formed in a generally trapezoidal shape in cross section is formed in the nut on an inner washer side, a projected part symmetrical with respect to the axis and formed in a generally trapezoidal shape in cross section is formed on the washer on an inner nut side, and the recessed part of the nut is fitted to the projected part of the washer, and a hole in the washer is positioned on the inner side of the projected part and the center position of the hole is positioned eccentric to the center position of the projected part of the washer.

Claim of invention:  
     
         1 . A tightening structure for locking, comprising a nut, a bolt, and a washer with a hole through which an axis of said bolt passes, wherein, a recessed part symmetrical with respect to said axis and formed in a generally trapezoidal shape in cross section is formed in said nut on an inner washer side, a projected part symmetrical with respect to said axis and formed in a generally trapezoidal shape in cross section is formed on said washer on an inner nut side, and said recessed part of said nut is fitted to said projected part of said washer, and said hole in said washer is positioned on the inner side of said projected part and the center position of said hole is positioned eccentric to the center position of said projected part of said washer.  
     
     
         2 . A nut for a tightening structure for locking, comprising a nut, a bolt, and a washer with a hole through which an axis of said bolt passes, wherein, a recessed part symmetrical with respect to said axis and formed in a generally trapezoidal shape in cross section is formed in said nut on an inner washer side.  
     
     
         3 . A washer for a tightening structure for locking comprising a nut, a bolt, and a washer with a hole through which an axis of said bolt passes, wherein, a projeted part symmetrical with respect to said axis and formed in a generally trapezoidal shape in cross section is formed on said washer on an inner nut side, and said hole in said washer is positioned on the inner side of said projected part and the center position of said hole is positioned eccentric to the center position of said projected part of said washer.  
     
     
         4 . A tightening structure for locking as set forth in  claim 1 , in which said recessed part of said nut is fitted to said projected part of said washer, wherein, said recessed part comprises an upper surface part and an sloping part, said projected part comprises an upper surface part and an sloping part, a form of the fitting is that said sloping part of said recessed part is formed in plane form and said sloping part of said projected part is formed in curved form.  
     
     
         5 . A tightening structure for locking as set forth in  claim 1 , in which said recessed part of said nut is fitted to said projected part of said washer, wherein, said recessed part comprises an upper surface part and an sloping part, said projected part comprises an upper surface part and an sloping part, a form of the fitting is that an angle of said sloping part of said recessed part is a little larger than an angle of said sloping part of said projected part.  
     
     
         6 . A tightening structure for locking as set forth in  claim 1 , in which said recessed part of said nut is fitted to said projected part of said washer, wherein, said recessed part comprises an upper surface part and an sloping part, said projected part comprises an upper surface part and an sloping part, a form of the fitting is that an angle of said sloping part of said recessed part is a little smaller than an angle of said sloping part of said projected part.  
     
     
         7 . A tightening structure for locking as set forth in  claim 1 , in which said recessed part of said nut is fitted to said projected part of said washer, wherein, said recessed part comprises an upper surface part and an sloping part, said projected part comprises an upper surface part and an sloping part, a form of the fitting is that an angle of said sloping part of said recessed part is the same as an angle of said sloping part of said projected part.  
     
     
         8 . A nut for a tightening structure for locking set forth in  claim 3 , in which said projected part is formed in curved form.  
     
     
         9 . A tightening structure for locking as set forth in  claim 1 , in which said projected part of said washer has a supporting part therebeneath.  
     
     
         10 . A washer for a tightening structure for locking as set forth in  claim 3 , in which said projected part has a supporting part therebeneath.  
     
     
         11 . A tightening structure for locking as set forth in  claim 9 , in which said supporting part is horizontal with respect to an tightened object.  
     
     
         12 . A washer for a tightening structure for locking as set forth in  claim 10 , in which said supporting part is horizontal with respect to an tightened object.  
     
     
         13 . A tightening structure for locking as set forth in  claim 1 , in which the ratio between a height of the female screwing part and a height of said recessed part in said nut is approximately 2 to 1.  
     
     
         14 . A nut for a tightening structure for locking as set forth in  claim 2 , in which the ratio between a height of the female screwing part and a height of said recessed part in said nut is approximately 2 to 1.  
     
     
         15 . A tightening structure for locking as set forth in  claim 1 , in which a sloping angle of said sloping part in said nut is approximately 10 degree with respect to the center axis.  
     
     
         16 . A nut for a tightening structure for locking as set forth in  claim 2 , in which a sloping angle of said sloping part in said nut is approximately 10 degree with respect to the center axis.  
     
     
         17 . A tightening structure for locking as set forth in  claim 1 ,  4 ,  5 ,  6 ,  7 ,  9 ,  11 ,  13 , or  15 , wherein a diameter of a circle consisting of the most heightened points of said sloping part of said projected part of said washer, is equal to or smaller than an diameter of the upper crossing points of said recessed part of said nut and a diameter of a circle consisting of the lower points of said sloping part of said projected part of said washer, is equal to or larger than an diameter of the lower crossing points of said recessed part of said nut.  
     
     
         18 . A tightening structure for locking as set forth in  claim 1 ,  4 ,  5 ,  6 ,  7 ,  9 ,  11 ,  13 ,  15 , or  17 , wherein a diameter of said hole of said washer is higher than a outer diameter of said female screwing part by the height of the ditch of the female screwing part of said nut.  
     
     
         19 . A tightening structure for locking as set forth in  claim 1 ,  4 ,  5 ,  6 ,  7 ,  9 ,  11 ,  13 ,  15 ,  17 , or  18 , wherein said nut is higher than said washer.  
     
     
         20 . A tightening structure for locking as set forth in  claim 1 ,  4 ,  5 ,  6 ,  7 ,  9 ,  11 ,  13 ,  15 ,  17 ,  18 , or  19 , wherein a thickness of the material of said washer is smaller than the pitch of said screwing part of said bolt.  
     
     
         21 . A washer for a tightening structure for locking as set forth in  claim 3  or  10 , in which a thickness of the material of said washer is smaller than the pitch of said screwing part of said bolt.