Patent GB-642407-A (GB)
Title: Gear finishing
IPC: B23F19/06
Filed: 1947-04-10
Abstract: 642,407. Gear - cutting. NATIONAL BROACH & MACHINE CO. April 10, 1947, No. 9587. Convention date, April 15, 1946. [Class 83 (iii)] A machine for finishing gears on the inter. meshing-generator principle comprises rotary supports for carrying, respectively, the work gear 7 and tool 6 on crossed axes, a motor for directly rotating one support, and positioning means for locating the work gear and tool in predetermined angular position during the relative approach of the supports between the work-loading and working positions, and means for releasing the positioning means prior to starting the motor. As shown in Fig. 1, two tool-carrying slides 4, 5, are reciprocable towards and away from a work-holding turret. The latter is loaded at stations C and D, and the work operated on at stations A and B. The turret comprises series of upper and lower gear-holding fixtures 14 and 15, Fig. 25, angularly spaced thereon, each upper fixture 15 being moved towards the lower fixture by means of a manually-operated handle 35. Each gear 7 is located in position by means of a manually-operated plunger 182. Each tool 6 is carried by a head 97, Fig. 11, which is angularly adjustable with respect to a carriage 98 secured to a slide 99 which is reciprocable with respect to the housing 96 of the slide 4, or 5, by means of a screw 118 rotated from a motor 146. Each tool 6 is rotated by means of a gear 112 which is also rotated from the motor 146. Each tool is located in position by means of a toothed locator disc 200 engaged by a toothed locator plate 202 which is operatively connected to pull and push solenoids. Each slide 4, or 5, is reciprocated by means of a cam 120, Fig. 10, driven by a motor 119 which also drives a dial plate 142 having dogs engageable with limit switches. The turret is indexable through 180 degrees by means of a driving index plate 61, Fig. 36, drawn from a motor 53 and cooperating with driven index and locking plates 71, 72 respectively. When it is desired to crown the work-gears, the carriage 98 is pivoted about pins 116, Fig. 8A, and is rocked by means of a cam 214 during the vertical reciprocation of the slide 99. In operation, as each handle 35 at the stations C and D is swung downwardly, a switch 222, Fig. 29, is closed and as the locator plunger 182 at each of these stations is operated to bring it into engagement with its respective work gear, a switch 226, Fig. 26, is closed. The closing of the switches 222 and 226 closes the circuit to the motor 53 so that indexing of the turret takes place until the circuit to the motor is broken by operation of a switch 94, Fig. 36, which closes the circuit to the motors 119 of the slides 4, 5. Each motor 119 drives its slide forwardly until a dog 228, Fig. 10, contacts a limit switch 229 to break the circuit to the motor 119 and make the circuit to a push solenoid 197, Fig. 26, which releases the plunger 182 from the work gear and causes a set-screw 233 to contact a limit switch 234 to make the circuit to the push solenoid, which moves the plate 202, Fig. 11, out of engagement with the disc 200 thereby releasing the associated cutter and operating a switch 230, Fig. 11, to close the circuit to the motor 146 thereby starting rotation of the associated cutter. Each motor 146 also moves the associated cutter head assembly downwardly until a dog 235 on the slide 99 contacts a limit switch 236, Fig. 7, on the housing 96 of the slide 4, or 5, to break the forward circuit to the motor 146 and make the reverse circuit to this motor as well as to close the circuit to the motor 119 which feeds forwardly until a dog 237, Fig. 10, contacts the switch 229 to break the circuit to the motor 119. The reverse drive of the motor 146 moves the cutter head assembly upwardly until a dog 238, Fig. 7, on the slide 99 engages a switch 239 on the housing 96 of the slide 4, or 5, to break the reverse circuit to the motor 146 and make the forward circuit to this motor as well as to make the circuit to the motor 119 which continues running until a dog 240, Fig. 10, operates the switch 229. These operations continue at both stations A and B for a predetermined number of reciprocations of the cutter head assembly until a dog 241, Fig. 10, operates a switch 242 to break the forward circuit of the associated motor 119 and make the reverse circuit of this motor as well as to break the circuit to the associated motor 146 so that the latter stops. The reversal of the motor 119 continues until the dog 228 operates the switch 229 which temporarily breaks the circuit to the motor 119 as controlled by a time-delay relay. During this temporary stoppage of the motor 119, the time-delay relay closes the circuit to the pull solenoid which moves the plate 202 into engagement with the disc 200 after which the time-delay relay effects the closing of the reverse circuit to the motor 119 to allow it to continue in, its reverse direction until the dog 241, Fig. 10, operates a switch 244 which breaks the circuit to the motor 119. Both slides 4, 5, are now in their original starting positions and the machine is ready for insertion of two semifinished or roughed-out work gears after those previously inserted have been removed. Tailstocks.-Each fixture 15, Fig. 30, comprises a spindle 24 journalled in a sleeve 23 which is moved against spring action by means of a slide 30 having a rack 32 which is connected to a manually-operated shaft 36 by means of a link 50. The fixture is locked in the workengaging position by means of a pin 37 which is engaged by an arm 43 of a three-armed lever 40 acted on by a cam 49 secured to the shaft 36.