GB529567A - Improvements in honing machines - Google Patents

Abstract

529,567. Honing tapered bores. BURGESS, A. F. (Barnes Drill Co.). Sept. 19, 1939, No. 26141. [Class 60] In honing long tapered or other bores in which tool and work are relatively reciprocated and rotated, the tool is expanded by power actuated means to apply a light pressure during relative travel in one direction and increased pressure in the other. The increase may be gradual but preferably it is increased to a maximum as soon as the direction is reversed. The work W is fixed and the tool 11 is rotated by an electric motor M2 and expanded, within the bore 20, by closing a switch SW by hand to energize a solenoid S<SP>2</SP> and move the valve V<SP>3</SP> into the position shown, whereby fluid from a pump P<SP>1</SP>, driven by the motor M<SP>2</SP>, is admitted to a cylinder 17 and thus advance the cams 14. The tool is reciprocated by cables 21, 22 connected to a drum 23 rotated by a reversible hydraulic motor M controlled by a valve V<SP>1</SP> which is operated by a pilot valve V<SP>2</SP> under the control of solenoids S, S<SP>1</SP> and switches LS, LS<SP>1</SP> operated by a projection 27 on the tool-slide at each end of its normal travel. When the tool moves to the right a frictionoperated switch SW1, carried by the tool-slide, is opened. The valve V<SP>6</SP>, however, also connects the pressure fluid to a relief valve V' adjusted to reduce its value so that the tool pressure is light. As soon as the direction of movement is reversed the switch SW<SP>1</SP> is closed, solenoid S<SP>3</SP> energized, and valve V<SP>6</SP> rotated to connect the fluid pressure supply to a relief valve V<SP>5</SP> adjusted to a higher value than V' so that the tool is expanded with greater force. When the machine is used for non-tapered work the switch SW2 is opened by hand.