Patent GB-336051-A (GB)
Title: Head translating mechanism for radial drills
IPC: B23B39/12
Filed: 1929-08-23
Abstract: 336,051. Cincinnati Bickford Tool Co., and Klausmeyer, D. C. Aug. 23, 1929. Drilling - machines. - A radial-arm drilling- machine has a rotatable shaft in the drill-head connected to the means for traversing the head along the arm and adapted to be rotated through one of two oppositely rotating gears thereon from a power shaft, the clutch for controlling the drive being actuated by a lever which disconnects the hand traverse simultaneously with the engagement of the power traverse. A brake may be provided to arrest the movement of the traversing means and overcome the momentum of the drillhead when the power drive is disconnected. The drilling-machine comprises a base 1, pillar 2,. radial arm 3 and drill head 4, the tool-spindle 5 being driven from a driving means 6 through gearing 7 and a shaft 8 journaled on the arm. The shaft 8 is driven at a constant speed and drives the drill in either direction through one of the bevel gears 9, 10, a shaft 12 and speedchange gears (not shown). The drill head is traversed along the arm by reversible skew gearing 14, 15, Fig. 2, and rack and pinion, screw and nut or other means 17, 18. The skew gear 14 is secured to a shaft 13 which may be rotated by a hand wheel 19 and a clutch 21 splined to the shaft, the clutch being moved axially by a lever 22. The shaft 13 may also be rotated by power from the arm shaft 8 through a bevel gear 34 splined thereon, belt drive 37 and a bevel pinion on the vertical shaft 29 which rotates bevel gears 26, 27 in opposite directions. A toothed clutch 38 for engagement with either of the wheels 26, 27 is splined to the shaft 13 by a pin passing through a slot therein and attached to a rod located within an axial bore in the shaft. The rod also carries a pin 42 passing through a slot 13t in the shaft and secured to a circular rack 43 with which meshes a pinion 45 attached to a spindle 44. A hand lever 46 is pivoted at 47 to the spindle and is provided with a rear ball-end 48 slidable in an arcuate guiding slot 49 on the drill head. The lever 46 passes through aT-slot 54, 55, Fig. 3, in the head, the action being such that movement in the slot 55 rotates the spindle 44, thereby moving the rack 43 axially and engaging the clutch 38 with either of the bevel gears 26, 27 to traverse the drill head by power. In this position of the lever 46 the end of the pinion 45 presses back the lever 22 against a spring s to disengage the hand traverse clutch 21, the clutch being only engagable after moving the lever 46 to the position where the clutch 38 is disengaged and then oscillating about the pivot 47 to move the lever along the slot 54, Fig. 3. Brakes, applications of.-A brake drum 56, Figs. 2 and 5, is secured to the shaft 13 and has co-operating therewith a shoe 57 pivoted to a lever 58 normally actuated to apply the brake by a spring 60 or by positive means (not shown). When the spindle 44 is rotated by the hand lever 46 to engage the clutch 38 with either of the gears 26, 27, a cam 63 on the spindle slides a rod 62 axially to cause a cam 61 thereon to rock the lever 58 and disengage the brake. The brake is also disengaged by axial movement of the cam 63 when the lever 22 is oscillated to engage the clutch 21 for hand traverse.