GB333749A - Power traverse for radial drill heads - Google Patents

Abstract

333,749. Cincinnati Bickford Tool Co., and Klausmeyer, D. C. Aug. 23, 1929. Drilling-machines.-In a radial-arm drilling- machine an electric-motor is mounted on the drill head and a control lever is provided for enabling the head to be traversed along the arm either from the motor or from a hand wheel on the head, the arrangement being such that both hand and power traverses cannot be in operation simultaneously. A rack-bar 4, Fig. 2, secured to the arm is engaged by a pinion 5 on the spindle 6 of a worm-wheel 8 which is in mesh with a worm 9 on a shaft 10. The shaft 10 may be rotated from a hand wheel 12 through a clutch 17 splined on the shaft and normally pressed against clutch teeth 15 on the hand wheel by a spring 39 within the shaft. A spigot p on the shaft engages a recess t in the hand wheel. The clutch 17 may be raised by a yoke 36 secured to a bar 33 vertically slidable in the head by means of rack teeth 38<a> thereon meshing with teeth on the end of a hand lever 40, Fig. 4, pivoted to a rod 41 which is rotatable but not slidable in the head. Power drive is transmitted to the worm 9 through a shaft 18 rotated through bevel gearing from a motor located at the top of the drill head, the shaft 18 having keyed thereto the outer part 22 of a friction clutch. The inner member 23 of the clutch carties a friction band 24 impinging at one end against a pin 25 Fig. 6, attached to the member 23 and expanded at the other end by a bevelled face 26 on a cam 27 rotatable on the member 23 by means of a lever 28 carrying an adjustable screw 29. The member 23 is keyed on the shaft 10 and has splined thereon a sleeve 31 provided with a wedge 30 adapted on endwise movement of the sleeve to rock the lever 28. A second yoke 34 on the bar 33 engages the. sleeve 31 to expand the friction clutch after the clutch 17 has been disengaged. A spring 42 normally depresses the bar 33 to engage the clutch 17 and if the teeth are not in the meshing positions the spring 39 allows them to remain in contact until operation of the hand wheel 12 permits them to engage. Rotary movement of the rod 41 by means of the lever 40 oscillates a toothed lever 45 to actuate a reversing switch for the motor, a notched lever 46 being provided on the rod and co-operating with a spring-pressed lever to return the switch to its neutral position as soon as the lever 40 is released. In a modification the friction clutch 22 is replaced bv a toothed clutch having bevelled teeth to allow slip.