An improvement in or relating to tool feed motions for metal-planing machines

摘要

563,878. Planing. SWIFT-SUMMERSKILL, Ltd., CARTER, J., and WADE, G. May 13, 1943, No. 7617. [Class 83 (iii)] In a feed motion for the tool box or boxes of a planing- machine, the feed is effected by an A.C. motor incorporating means actuated by the application of D.C. to bring it to rest rapidly, and is applied by rotation of the motor in one direction, rotation in the other direction effecting a quick power traverse of the tool box to starting position. A threephase star connected squirrel cage motor a, Fig. 1, has two of the windings adapted to be connected through switching means to a D.C. supply, such as the generator which supplies the work table reciprocating motor. Two worms b1, b2 driven by the motor a engage worm-wheels c, k1 which are connected by oneway clutches e, k of opposite hand to a shaft d and a crank disc j1 respectively. A link i1 connects the crank disc to a toothed-quadrant i meshing with a gear h carrying a pawl g engaging a ratchet f secured to the shaft d. While the table reciprocation is being reversed the motor a is switched in to rotate the crank disc j1 by means of the clutch k through one complete revolution as determined by a spring detent m and during the first half of the revolution the segment i is rocked to rotate the shaft d which thus effects the tool-box feed, an adjustable shroud on the ratchet f determining the extent of the feed, and the second half of the crank rotation restoring the pawl g to its original position. When the motor a is rotated in the reverse direction, the clutch k overruns and the clutch e rotates the shaft d in a direction to traverse the tool box by power. A spring- actuated cam n engages a pulley n1 secured to the shaft d to prevent the feed ratchet f from being rotated reversely. In a modified construction, a single worm driven by the motor a rotates a worm-wheel p, Fig. 4, which carries one-way clutches p1, p2 of opposite hand connected respectively to an eccentric p3 and the feed shaft d. For feeding the tool box, the motor is rotated in a direction to drive the eccentric which oscillates a toothed quadrant p7 through a link and shaft p6, the quadrant rotating a gear p8 through one revolution to actuate a pawl p9 and drive the shaft d in the direction of arrow C by means of a ratchet r thereon and an adjustable mask, whilst for power traverse of the tool the motor is driven in the reverse direction to rotate the shaft d in the direction of arrow D. As in the first construction, a cam engages a pulley n1 on the shaft d to prevent reverse rotation whilst the pawl p9 is being retracted and a spring detent ensures the clutch p1 making a single revolution only during feed.