Patent GB-472557-A (GB)
Title: Improvements relating to change speed or other indicators for drilling and other machine tools
IPC: B23Q1/00
Filed: 1936-04-24
Abstract: 472,557. Indicating speed-changes in drilling &c. machines. ASQUITH, Ltd., W., O'ROURKE, F., and JOHNSON, A. April 24, 1936, Nos. 11680 and 27992. [Class 83 (iii)] In a change speed or other indicator for drilling &c. machines in which a lever is used to impart endwise and rotary movement to a shaft connected with the gear box, the lever actuates a movable indicating device on the indicator and-the indicator is mounted so that it can be tilted to any angle in order to enable the indications to be observed in all positions of the tool-head &c. to which the indicator is attached. As applied to the change speed control of a drilling machine, the shaft B which operates nine speed changes, is moved axially by movement of a hand lever C pivoted to a bracket D having a boss d freely rotatable on the shaft. Lateral oscillation of the lever C together with the bracket rotates the shaft B. Axial motion of the shaft is transmitted by levers e, e<2> to a rod F sliding at right angles to the shaft B and connected by a bell-crank lever l to a block M which is vertically slidable on guides m<1> on a bracket J. A sleeve H on the rod F is connected by a lever y to the boss d of the lever C so that lateral movements of the lever C move the sleeve axially to cause the bracket J to be displaced horizontally on guides j<1> in the indicator casing K. A pin c<1> operates in a gate n of the casing A to determine the different speed positions of the lever C and a screw m<2> on the block having a distinctively coloured head is moved in synchronism with the lever C to indicate the position of the pin c<1> through an apertured plate k<1>. A plate k<3>, Figs. 5 and 6, is located behind the plate k<1> and is displaceable laterally by means of rack teeth k<5> thereon and a pinion rotatable by a hand lever k<9>, a spring pin co-operating with recesses k<11> to locate the plate in any one of four positions. Vertical rows of slots k<2> are provided in the plate k<1> and horizontal rows of slots k<4> in the plate k<3>. In operation, in order to set the spindle speed, e.g. for drilling an inch and a quarter hole in cast iron, the plate k<3> is moved laterally to show the number 55 opposite the cutting-speed slot in the plate k' for cast iron, and the hand lever C is then moved until the coloured screw m<2> is seen at an intersection of the slots k<2>, k4 which is nearest to the inch and a quarter indication on the plate k<3>. Single and double gear trains are controlled by a separate lever, (not shown), the upper figures 600 &c. on Fig. 5, being marked in green for double gears and the lower figures 60 &c. being marked in cream for single gears. For drilling a different material, e.g. aluminium, the rear plate k<3> is moved by the handle k<9> to cause the number 200 to appear in the cutting speed slot of the plate k<1> marked aluminium. A track k<12>, shown shaded in Fig. 5, is provided on the plate k<1> to indicate the direction of movement of the lever C required to pass the pin c<1> through the gate n. The plate k<1> is removable to allow the plate k<3> to be replaced by a different plate, e.g. by one having numbers such as 1 ... 4 thereon which show through the slots k<2> in turn as the plate is moved laterally in order to indicate the successive positions to which the coloured screw m<2> must be set for performing a sequence of operations. The casings A, K are attached to the drill carriage, and in order to enable the plates k<1> &c. to be read at any elevation of the carriage, the casing K is rotatably adjustable at a<1> on the casing A so that it may be set at right angles to the operator's line of vision, and locked by a handle k.