Patent GB-454089-A (GB)
Title: Method of and device for dressing or trueing profiled grinding discs for grinding toothed wheels having oblique teeth
IPC: B24B53/075
Filed: 1934-12-21
Abstract: 454,089. Trueing grinding wheels. ZAHNRADFABRIK FRIEDRICHSHAFEN AKT.-GES., Friedrichshafen, Germany. Dec. 21, 1934, No. 36768. Convention date, Dec. 22, 1933. [Classes 60 and 124] A profiled grinding.disc employed for grinding toothed gears with helical teeth of involute profile is trued by a diamond &c. tool, which is mounted on a support set between the work centres of the carriage of grinding-machine so as to occupy the position of a gear-wheel to be subsequently ground, and is constrained by guiding-means so that by longitudinal movement of the carriage and swinging movement of the support and tool, the working-point of the tool is caused to move along a curved path corresponding to the line of contact between the grinding-disc and a gear-tooth to be ground ; the tool is held on the support by a guidemember which is set to the helical angle of the gear-wheel, whereby the point of the tool moves along a straight line directed similarly to the lines of simultaneous contact of two co-operating gear teeth and also moves along a helical path. The device comprises a support 10 mounted beneath the grinding-disc 1 on the work-centres 2, 3 on the carriage 54, and in the support is a rotatably adjustable shaft 11 carrying a body 12, the body being set to the helical angle of the gear to be ground by means of a gauge block 17 and pins 15, 16 on the parts 10, 12 respectively ; the body 12 is adjusted for height by distance-pieces 25. Slidable on the body 12 on raised points 14<1> is a frame 14 rotatably supporting the holder 23 of the trueing tool 13, and pivoted to the holder 23 at 26 are two guide rods 19, which are constrained to lie in radial planes of the disc 1 by means of rollers 20 and spring-controlled rollers 22 carried by a guide part 21<1> rotatably mounted on a fixed carrier bolt 21 ; the rods 19 are fluted at their slide surfaces which contact with the guide 21<1> to avoid inaccuracy due to grinding-dust &c., and the rods are held in spaced relationship by bolts 19<1>. In operation, the carriage 54 is moved along the machine, the support 10 &c. being at the same time rotated, so as to produce a helical movement, by bands 33 wrapped round a disc 34 which turns the support 10 by a member 35, the bands being moved by a rod 30 moved transversely of the machine by a pin 31 engaging an angularly placed slide 32. These movements combined with the restraint imposed by the rods 19, cause the point of the tool 13 to move in the desired path across the face of the grinding-disc. The parts near the outer edge of the grinding-disc, which treat parts of the gear teeth at the roots and below the operative faces of the teeth, are trued with the guide part 21<1> moved from the radial plane of the disc, the bolt 21 being mounted for this purpose in a carrier 42 pivoted at 37 on the machine frame, and the carrier being located in its two positions by locking means 39. The Specification as open to inspection under Sect. 91 comprises also the provision of raised supporting points on the holder 23. This subject-matter does not appear in the Specification as accepted.