Mechanism for periodically forging screws

Abstract

A periodically transferring mechanism for a self-drilling screw forming machine includes a gear system and a clutch device which controls the engagement of the contact between the contact member of the clutch device and the hosing mounted on the driven shaft. The clutch device is eccentrically connected to a idle gear which has two times of the number of teeth to the active gear so that the clutch device periodically contacts the hosing. A rating switch device is used to switch the transferring rate of the mechanism from 1:1 mold to 2:1 mold.

What is claimed is:  
     
         1 . A periodically transferring mechanism comprising: 
 a base ( 10 ) having an active shaft ( 2 ) and a driven shaft ( 6 ) connected thereto;    a gear system ( 20 ) including an active gear ( 21 ), a first idle gear ( 22 ), a second idle gear ( 23 ) and a driven gear ( 24 ) on which a housing ( 25 ) and a top plate ( 26 ) are mounted, a number of teeth of the first idle gear ( 22 ) being twice of the number of teeth of the active gear ( 21 ), the second idle gear ( 23 ) and the driven gear ( 24 ), the active gear ( 21 ) fixedly mounted to the active shaft ( 2 ), the driven gear ( 24 ) mounted to the driven shaft ( 6 ), a slot ( 241 ) defined in a top surface of the driven gear ( 24 ) and a hole ( 242 ) defined in an inside of one end of the periphery of the slot ( 241 ), a hosing ( 25 ) mounted to the driven shaft and a flange ( 251 ) extending outward from a periphery of the hosing, a groove ( 252 ) defined longitudinally in an outer periphery of the hosing ( 2 ), a top plate ( 26 ) connected to the hosing and the driven shaft;    a connection member ( 30 ) engaged with the groove in the hosing and a block ( 32 ) extending outward therefrom, a spring ( 33 ) mounted to the connection member ( 30 ) which is inserted in the grove ( 252 ), the spring ( 33 ) biased between the top plate ( 26 ) and the block ( 32 );    a clutch device ( 40 ) having a crank ( 41 ), a rod ( 42 ), a retractable bar ( 43 ), a contact member ( 44 ) and a fix member ( 45 ), one end of the crank ( 41 ) pivotably and eccentrically engaged with the first idle gear ( 22 ) and the other end of the crank ( 41 ) connected to the rod ( 42 ) which has a recess ( 421 ) for receiving a spring ( 46 ) therein, the retractable bar ( 43 ) movable in the recess ( 421 ) of the connection rod ( 42 ), a contact member ( 44 ) connected to the retractable bar ( 43 ) and disengagably contacting the flange ( 251 ) of the hosing ( 25 ), and    a casing ( 50 ) fixed to the base ( 10 ) and mounted to the gear system ( 20 ), the connection ( 30 ) and the clutch device ( 40 ), a convex portion ( 52 ) located on the casing ( 50 ) so as to receive the driven shaft ( 6 ), the hosing ( 25 ) and the top plate ( 26 ).    
     
     
         2 . The mechanism as claimed in  claim 1 , wherein the top plate ( 26 ) has a position hole ( 261 ) for being engaged with the connection member ( 30 ).  
     
     
         3 . The mechanism as claimed in  claim 1 , wherein connection member ( 30 ) is a pin ( 31 ) having an insertion ( 311 ) at a lower end thereof and the block ( 32 ) has a protrusion ( 321 ) on a center of the bottom thereof and an inclined surface ( 322 ) is defined on each of two ends of the block ( 32 ), the insertion ( 311 ) inserted in the hole ( 242 ) in the slot ( 241 ).  
     
     
         4 . The mechanism as claimed in  claim 1 , wherein a pin ( 47 ) is fixedly inserted in a recess ( 431 ) in the retractable bar ( 43 ) so that the retractable bar ( 43 ) can be movable in the recess ( 421 ) in the connection rod ( 42 ).  
     
     
         5 . The mechanism as claimed in  claim 1 , wherein the connection rod ( 42 ) is inserted in a hole ( 451 ) in the fix member ( 45 ).  
     
     
         6 . The mechanism as claimed in  claim 1 , wherein the contact member ( 44 ) has a contact surface ( 441 ) which contacts the flange ( 251 ) of the hosing ( 25 ), a concave surface ( 442 ) defined on a top of the contact member ( 44 ) and two inclined surface ( 443 ) defined on two ends of the contact member ( 44 ), the inclined surface ( 322 ) on the block ( 32 ) of the connection member ( 30 ) moving upward along the inclined surface ( 443 ) on the contact member ( 44 ) when the connection member ( 30 ) is rotated with the driven gear ( 24 ), the protrusion ( 321 ) on the block ( 32 ) engaging with the concave surface ( 442 ) on the contact member ( 44 ) when the driven gear ( 24 ) is rotated.  
     
     
         7 . The mechanism as claimed in  claim 6 , wherein the contact member ( 44 ) has a stop recess ( 444 ) so as to stop the contact member ( 44 ).  
     
     
         8 . The mechanism as claimed in  claim 1 , wherein the casing ( 50 ) has central opening and two holes ( 53 ) defined in the convex portion ( 52 ), the two holes ( 53 ) located in communication with the position hole ( 261 ) in the top plate ( 26 ) and the stop recess ( 444 ) in the contact member ( 44 ).  
     
     
         9 . The mechanism as claimed in  claim 1 , wherein a rating switch device is connected on the casing ( 50 ) and a receiving area ( 61 ) is defined in a side of the rating switch device ( 60 ), the receiving area ( 61 ) sealed by a cover ( 62 ) to which an active gear shaft ( 63 ), a first gear shaft ( 64 ) and a second gear shaft ( 65 ) are rotatably extended, a switch member ( 66 ) connected to the casing of the rating switch device ( 60 ) and connected to the active gear shaft ( 63 ), two passages ( 67 ) defined through the casing of the rating switch device ( 60 ) so that a first rack ( 68 ) and a second rack ( 69 ) are inserted therein, the first rack ( 68 ) engaged with the first gear shaft ( 64 ) so as to move up and down, a position pin ( 687 ) on a lower end of the first rack ( 68 ) engaged with the position hole ( 261 ) in the top plate ( 26 ), The second rack ( 69 ) is engaged with the second gear shaft ( 65 ) and movable up and down, a stop pin ( 691 ) on the lower end of the second rack ( 69 ) and engaged with the stop recess ( 444 ) in the contact member ( 44 ).  
     
     
         10 . The mechanism as claimed in  claim 1 , wherein the first rack ( 68 ) includes a toothed sleeve ( 681 ) connected to a hat member ( 683 ) having guide slot ( 682 ), a core ( 685 ) having a spring ( 684 ) mounted thereto and extending through the hat member ( 683 ), a position pin ( 686 ) connected to the core ( 685 ) and movable in the guide slot ( 682 ).