478,290. Honing cylinders. BURGESS, A. F. (Barnes Drill Co.) Jan. 29, 1937, No. 2671. [Class 60] A machine for honing long internal cylindrical surfaces, for example, gun barrels, comprises a honing tool 40 with expansible abrasive members 39 and fibre supporting members 41, rotated and reciprocated in the work, which is supported in stationary supports with its axis horizontal. The machine comprises a bed 1 carrying the driving means for the hone spindle, and a bed 2 supporting the work. The bed 1 has side walls 3 with inwardly projecting flanges and carries longitudinal cylindrical rods 6, upon which the spindle carriage 7 is moved, the carriage being supported by double conical rollers 25, 27 running on ball bearings on studs 24 depending from the carriage and engaging the rods 6. The carriage has thereon an electric motor 17 driving, through gearing in a housing 11, a spindle 12 to which the hone 40 is secured. The carriage is reciprocated by means of cables 64, 65 each having one end secured to a lug 67 on the carriage, and the cables are wound round a grooved drum 45 and secured at their other ends thereto, the cable 65 passing round a sheave 69 carried by a lever 72 acted upon by a spring 77, whereby the cable is tensioned, and shock, due to reversal of the cable, is diminished. The drum 45 is driven through gearing 49, 50, 54, 55, by a fluid motor 56, to which fluid is supplied by a pump 57 driven by an electric motor 60. The work bed has thereon adjustable work holders 80 and a member 81 against which one end of the work 82 abuts in fluid tight contact, a duct 81a serving to supply cooling fluid from a conduit 83, the fluid being supplied by a pump 100 driven by a motor 101, from a reservoir 99 to which the fluid returns through a screen 97 and a filter 98. The bed also carries a bracket 84 on which is adjustable, by rack gearing 89, 94, a member 87 carrying a tool guiding sleeve 91 serving to guide the tool 40 as it enters and leaves the work, the end of which contacts with the bevelled end of the sleeve 91. The operations of the machine are controlled by means of manual control members including a shaft 102 slidable within a sleeve 104, which is rotatable in a bearing 108 in the wall 3, the shaft normally being positioned axially by compression springs 105 and its axial movement being limited by collars 107 and bearing members 103. The shaft 102 is movable by the arm 116 of a control lever 113 pivoted at 111 to a rib 110 on the sleeve 104, the lever also carrying a spring-pressed pin which normally, by engagement with a shoulder 112 on the rib 110, prevents movement of the lever past the neutral position shown in Fig. 3, wherein the machine is at rest; the sleeve 104 also may be rotated by the lever 113. Movement of the shaft 102 actuates a switch controlling member 125, which moves an arm 126a to engage one or the other of two push buttons 127, 128, and rotation of the sleeve 104 actuates, through an arm 131, a link 129, which, through a bell-crank lever 133 actuates a valve 58 to start or stop the fluid motor 56 ; a push button switch to control the motor 60 also is provided. Movement of the carriage is reversed automatically by a reversing- valve 59 controlling the motor 56, the valve being moved, through a stem, by a cam moved by a stop bar 149 carrying two fixed stops 157, 158 and a pawl stop 159, which are engaged by a lug 160 on the carriage ; the stops 157, 159 control the normal working reciprocation of the carriage, and when the work is completed, the bar 149 is rotated by a lever 150 so that the dog 159 is moved out of the path of lug 160. The carriage then moves to withdraw the tool from the work until its movement is arrested by the movement of the stop 158. The electrical circuits to the various motors are controlled by switches operated by solenoids, the circuits of which are controlled by the push buttons. A fibre ring 44 is provided on the tool spindle to support the tool as it is withdrawn until it is within the sleeve 91. Electric current is led to the motor 17 by a cable which is wound on and unwound from the drum 45 as the carriage reciprocates, the current being taken from the drum to the switches by slip rings 167 and brushes 169. U.S.A. Specification 1,945,044 is referred to.