Stopping device for an eyelet button holing machine

Abstract

A stopping device for an eyelet button holing machine provides a stopper arm which plunges into a recess portion of a stopper cam positioned coaxial to the main shaft. To absorb the stopping impulse, extra wheel cams are provided coaxial to the main shaft which induce the stopper arm to be inclined such that its position causes a clutch pulley to contact with a low speed pulley and then the stopper arm plunges into the recess portion of the stopper cam. Thus, the machine is stopped in two steps and the stopping impulse force is effectively alleviated.

What is claimed: 
     
       1. In an eyelet button holing machine which provides a stopper cam at a main shaft, a stopper arm having a stopper hook which is arranged to engage with said stopper cam by plunging said stopper hook into a recess portion of the stopper cam, a stopping device comprising: (a) wheel . .cams.!. .Iadd.cam means .Iaddend.provided at the main shaft . .and arranged to vary.!. .Iadd.for varying .Iaddend.the inclination of the stopper arm by engaging with the stopper arm.Iadd., wherein said wheel cam means includes at least two cams.Iaddend.;   (b) a high-speed pulley . .adapted to transmit.!. .Iadd.for transmitting .Iaddend.the high speed of the main shaft;   (c) a low-speed pulley . .adapted to transmit.!. .Iadd.for transmitting .Iaddend.the low speed of the main shaft;   (d) a clutch pulley slidably placed between said high-speed pulley and said low-speed pulley;   (e) a clutch cam . .adapted to rotate.!. .Iadd.for rotating .Iaddend.in association with the stopper arm; and   (f) a yoke . .adapted to cause said clutch pulley to contact.!. .Iadd.for effecting contact of said clutch pulley either .Iaddend.with said high-speed pulley or with said low-speed pulley by rotating said clutch cam.   
     
     
       2. A stopping device for an eyelet button holing machine as recited in claim 1, further comprising an eccentric shaft inserted into said yoke such that the contact positions between the clutch pulley and the high-speed pulley and the clutch pulley and the low-speed pulley may be adjusted. .Iadd. 
     
     
       3.  A stopping device for an eyelet button holing machine as recited in claim 1, wherein said wheel cams include means for varying the inclination of the stopper arm so that said clutch pulley contacting said high-speed pulley then contacts said low-speed pulley, and finally stops between said high-speed pulley and said low-speed pulley. .Iaddend..Iadd.4. A stopping device for an eyelet button holing machine as recited in claim 1, comprising a sustaining shaft around which said clutch cam is rotatable, and wherein said clutch cam comprises: a first convex portion in which said clutch cam has a rotational radius R P  with respect to said sustaining shaft;   a second convex portion in which said clutch cam has a rotational radius R N  with respect to said sustaining shaft; and   a concave portion, located between said first convex portion and said second convex portion, said clutch cam having a minimum distance R S  from said sustaining shaft, R P  being larger than R S , and R S  being larger than R N . .Iaddend..Iadd.5. A stopping device for an eyelet button holing machine as recited in claim 4, further comprising a ball roller, coupled to said yoke, said ball roller contacting said clutch cam when facing said first convex portion and said second convex portion of said clutch cam, and said ball roller being offset from said clutch cam when facing the concave portion of said clutch cam,   wherein said clutch pulley contacts said high-speed pulley when said ball roller faces said first convex portion, said clutch pulley contacts said low-speed pulley when said ball roller faces said concave portion, and said clutch pulley is located at a neutral position between said high-speed pulley and said low-speed pulley when said ball roller faces said second convex portion. .Iaddend..Iadd.6. A stopping device for an eyelet button holing machine as recited in claim 1, wherein said wheel cams are engaged with the main shaft, said wheel cams comprising:   a first wheel cam having a first recess; and   a second wheel cam having a second recess and being smaller than said first wheel cam, said first wheel cam and said second wheel cam being incorporated so that the first recess is offset from the second recess,   wherein said clutch pulley contacts said high-speed pulley until the stopper arm located apart from the first cam wheel contacts said first wheel cam,   wherein said clutch pulley contacts said low-speed pulley until the stopper arm contacting said first wheel cam contacts said second wheel cam through the first recess of said first wheel cam, and   wherein said clutch pulley stops between said high-speed pulley and said low-speed pulley when the stopper arm contacting said second wheel cam through the first recess of said first wheel cam is plunged into the second recess of said second wheel cam, and the stopper hook is plunged into the recess portion of the stopper cam. .Iaddend..Iadd.7. A stopping device for an eyelet button holing machine as recited in claim 1, further comprising a positioning roller, engaged with the stopper arm, which positioning roller changes, in cooperation with said wheel cams, speed of the main shaft, whereby the stopper arm is engageable with said wheel cams   
     
     
        through said positioning roller. .Iaddend..Iadd.8.  A stopping device for an eyelet button holing machine as recited in claim 7, further comprising means for rotatably engaging said positioning roller with the stopper arm. .Iaddend..Iadd.9. A stopping device for an eyelet button holing machine as recited in claim 7, wherein said wheel cams are engaged with the main shaft, said wheel cams comprising: a first wheel cam having a first recess; and   a second wheel cam having a second recess and being smaller than said first wheel cam, said first wheel cam and said second wheel cam being incorporated so that the first recess is offset from the second recess,   wherein said clutch pulley contacts said high-speed pulley when said positioning roller located apart from the first cam wheel contacts said first wheel cam,   wherein said clutch pulley contacts said low-speed pulley when said positioning roller contacting said first wheel cam contacts said second wheel cam through the first recess of said first wheel cam, and   wherein said clutch pulley stops between said high-speed pulley and said low-speed pulley when said positioning roller contacting said second wheel cam through the first recess of said first wheel cam is plunged into the second recess of said second wheel cam, and the stopper hook is plunged into the recess portion of the stopper cam. .Iaddend..Iadd.10. A stopping device for an eyelet button holing machine as recited in claim 9, further comprising means for rotatably engaging said positioning roller with the stopper arm, said positioning roller being plunged into the second recess of said second wheel cam while rotated relative to the stopper arm. .Iaddend..Iadd.11. A stopping device for an eyelet button holing machine as recited in claim 1, further comprising shock absorber means, coupled to the stopper arm, for absorbing shock applied to the stopper hook. .Iaddend..Iadd.12. A stopping device for an eyelet button holing machine as recited in claim 11, wherein said shock absorber means comprises a spring provided for the stopper arm. .Iaddend.