Self-contained feed roll for power punch presses

Abstract

A self-contained unit to be attached to a power punch press to provide a feed for stock being fed to the press. The unit contains a direct drive from the punch press crankshaft to feed rolls which are located adjacent to the table of the press. A non-slip, positive, drive is provided from the crankshaft of the punch press to an index drive which receives continuous, uniform rotary motion and converts it into non-continuous, incremental movement of the index drive output shaft. A positive, non-slip drive is provided between the index drive output shaft and the power driven feed roll. The feed roll unit also contains a compressed air-operated cylinder arrangement to release the idler feed roll at a predetermined period during the punch press cycle so that the stock being fed to the press is free from the feed rolls during the pressing portion of the punch press operating cycle. A cam secured to the punch press crankshaft actuates a solenoid valve which, in turn, opens a pilot valve and permits flow of compressed air to reverse the power cylinder, which normally urges the idler feed roll against the power driven feed roll, and thereby releases the idler feed roll to release the stock between the feed rolls of the self-contained unit.

I claim: 
     
       1. A self-contained feed roll unit for a power punch press having a crankshaft rotating in timed relation to the pressing portion of the operating cycle of said punch press, said feed roll unit comprising: (a) a power driven feed roll;   (b) an idler feed roll rotatably supported on a movable frame and normally urged toward said power driven feed roll, said idler feed roll being periodically moved away from said power driven feed roll by feed roll release means to free stock being fed to said power pass during the pressing portion of said power press operating cycle;   (c) an index drive having an input shaft to receive continuous, uniform rotary motion and an output shaft transmitting non-continuous, incremental rotary motion;   (d) first positive drive means drivingly connecting said index drive input shaft to said power press crankshaft; and   (e) second positive drive means .[.drivingly connecting.]. .Iadd.including a first drive member connected to said index drive output shaft, a driven member connected to said power driven feed roll, an idler member drivingly connected to said first drive member and said driven member to thereby drivingly connect .Iaddend.said index drive output shaft to said power driven feed roll, said second positive drive means being adjustable to vary the ratio of the angular velocity of said index drive output shaft relative to said power driven feed roll.   
     
     
       2. The self-contained feed roll unit of claim 1 wherein said second positive drive means is formed of chains and sprockets connecting said index drive output shaft and said power driven feed roll and the length of stock fed to said power press is varied by changing the sizes of said sprockets. 
     
     
       3. The self-contained feed roll unit of claim 1 wherein said feed roll release means comprises: (a) a compressed air powered reversible cylinder normally urging said idler feed roll frame toward said power driven feed roll, but actuatable to move said feed roll frame away from said power driven feed roll;   (b) cam means connected to said punch press crankshaft to actuate an electrical solenoid valve while said press is in said pressing portion of said operating cycle;   (c) pilot valve means actuated by said solenoid valve to control flow of compressed air to said reversible cylinder; and   (d) a compressed air circuit between a source of air under pressure and said reversible cylinder and controlled by said pilot valve means to reverse said cylinder when said cam means actuates said solenoid valve. .Iadd. 4. The self-contained feed roll unit of claim 1 wherein the length of the stock fed to said power press is varied by changing the size of at least one of said first drive member, said idler drive member and said driven member. .Iaddend..Iadd. 5. The self-contained feed roll unit of claim 1 wherein the length of stock fed to said power press is varied by changing the size of said idler drive member. .Iaddend..Iadd. 6. The self-contained feed roll unit of claim 1 wherein the length of stock fed to said power press is varied by changing the size of said first drive member. .Iaddend..Iadd. 7. The self-contained feed roll unit of claim 1 wherein the length of stock fed to said power press is varied by changing the size of said driven member. .Iaddend. .Iadd. 8. The self-contained feed roll unit of claim 1 which includes,   means to adjust said idler drive member relative to said first drive member and said driven member to permit mounting different sized first drive members, idler drive members and driven members to thereby vary the length of the stock fed to said power press. .Iaddend..Iadd. 9. The self-contained feed roll unit of claim 1 which includes,   means mounting said index drive output shaft in fixed spaced relation to said power driven feed roll. .Iaddend.