Patent GB-607725-A (GB)
Title: Hydraulic control means for feeding the cutters of cylinder boring machines and the like
IPC: B23Q5/26
Filed: 1946-01-22
Abstract: 607,725. Boring engine cylinders. PADDON, W. Jan. 22, 1946, No. 2130. [Class 83 (iii)] [Also in Group XXVIII] A cylinder boring machine comprises a cutter spindle and a cylinder in laterally spaced relation to each other, a pump for raising a piston in the cylinder to move the cutter spindle upwardly, and means for permitting controlled escape of the liquid from the cylinder to permit downward feeding of the cutter spindle. The cutter spindle 3, Fig. 1, is mounted in a quill 7 carried by a head 5 to which is secured a rod 6 having a piston 7 in a cylinder 8, and is rotated from a pulley 12 mounted in the head and in splined engagement with a driving shaft 14. The cylinder is secured to a casing 16 that contains a gauze-covered sump 85 for a pump 17 and is mounted on or is integral with a support 9 that has open slots for attaching the machine to a cylinder block and carries a split sleeve 19 for guiding the quill. A flexible drive from an electric motor, by means of a three-speed belt drive 24 maintained taut by a compression spring 29 acting on an arm pivoted at 27, drives a shaft 20 in the casing 16 and by means of a dog clutch 36, Fig. 4, operated by a fork on a shaft 37, Fig. 5, having a handle 65, the shaft 20 can drive either a pinion 32 on the driving shaft 14 or a pinion 34 on a shaft 21 operating the pump 17. The pump may be of any suitable type; a four-cylinder reciprocating type is described, having suction ball-valves 42 and spring-pressed pistons 39 operated by eccentrics 38 on the shaft 21. The pump may also be operated by a hand wheel 45 through a dog clutch 47. Oil is delivered by the pump through a ball valve 43 to the lower end of the cylinder and an air vessel mav be inserted in the line to smooth out the flow. During boring, the quill descends under gravity and the oil flows to the sump through a pipe 54, Fig. 5, filter 48, adjustable feed valve 50, pipe 57, valve 69 and pipe 71 that splashes the oil over the gears 31, 32. The feed valve block also has a spring-pressed valve 49 that can be depressed to allow the oil to flow directly, back to the sump through a pipe 64 so that the cutter spindle may be lowered rapidly preparatory to starting the cutting operation. The valve 69 is operated by a fork on the shaft 37 and is closed in the neutral and pump-driving positions of the lever 65, and open in the cutter-driving position. A pipe 72 is connected to the cylinder immediately below the fully-elevated position of the piston and leads either to the sump or is connected to the pipe 71; a sight feed indicator may be fitted in the pipe 72 to indicate when the piston is fully elevated. A lever 76a may be depressed against the action of a spring 77 to lower the cutter spindle and leave a slight lateral clearance between the races of the taper roller bearing 78 so that a spring (not shown) may withdraw the cutter from the face of the finished bore. Centring pins 81 are movable outwardly by the tapered end of a sleeve 7.9 that engages a nut 83 rotated by a gear on a spindle 84. Stop-motions.-An adjustable collar 74 may be fitted on the quill to engage the sleeve 19 to limit the depth of feed or a trip bar 75 having an adjustable collar 76 engaged by the head may be provided to actuate means for moving the handle 65 to the neutral position.