Patent GB-529449-A (GB)
Title: Improvements in or relating to machines for grinding bodies of rotation having curved generatrices
IPC: B24B5/16
Filed: 1939-05-19
Abstract: 529,449. Grinding. AKTIEBOLAGET SVENSKA KULLAGERFABRIKEN. May 19,1939, No. 15022. Convention date, June 17, 1938. [Class 60] In machines comprising a relatively oscillating and sliding work-head and grinding-wheel for making curved articles such as bearing rollers or races, the workhead is provided with holders for two work-pieces which are operated on simultaneously and have their axes arranged parallel and symmetrically to a plane which is normal to the axis of oscillation, and contains the axis of the grinding-wheel. The two articles produced at each operation are identical in size and shape and, provided the space between the articles is small in relation to the diameter of the grinding-wheel, the deviation from a truly circular shape is insignificant. The machines may be provided with means for releasing the finished articles and inserting new work-pieces. The machine may also be provided with a gauge for stopping feed when the articles have been ground to the required size. In the machine shown in Fig. 5, the work-head 2 is mounted on cross-slides on a table 12 mounted on a vertical pivot 110 which is oscillated by means of a slide 19 and crank 18 driven by a pulley 17 on a shaft 22. The work-head supports two shafts 49, Fig. 8, provided with centres for the work-pieces 3, and supports also another pair of shafts which are provided with driving-plates for the workpieces and are driven by an internal gear on a pulley. The shafts 49 abut at the outer end on springs which engage adjusting-nuts. The other shafts are pressed by springs, acting through ball-bearings, against abutments consisting of threaded sleeves which are adjustable to bring the driving-plates into the same plane. For simultaneously releasing the articles, the shafts 49 have flanges 50 co-operating with a flange 54 on a slide 53 geared to a hand-lever 61. On operation of the hand-lever, the centres are withdrawn, and the articles fall along deflectors 62. A spring 55 returns the slide 53 to the normal position, this being determined by adjustable stop-nuts 58 on a rod 57. The grinding-wheel 1 is mounted on a slide 7 geared to a shaft 76 which is driven through reducing- gearing 79 ... 82, Fig. 9, from the shaft 22. A device for inserting new work-pieces in position consists of a pivoted arm 24, Fig. 5, provided with spring-claws 25 for the work-pieces. The arm is normally held in forward position by a spring 27, and is moved rearwards to position the work-pieces between the centres and driving-plates on the work-head. When the articles have been ground to the required size, feed of the grinding-wheel is stopped by means including a pivoted, spring-urged gauge-finger 63, Fig. 9, co-operating with one of the workpieces. When the work-piece releases the gauge-finger, contacts 64, 65 are closed, a solenoid 66 is energized, a spring-urged lever 72 is released, a clutch-member 77 for the gear 79 is released from the shaft 76, and the slide 7 stops. The gauge-finger is restored and the spring thereof tensioned when the arm 24 is again moved rearward. The lever 72 is restored manually. Since the articles are ground to the same size, only one gauge-finger is necessary. A ring may be employed instead of the wheel 1, the work-pieces being in contact with the edge of the ring and arranged symmetrically to a plane which is normal to the axis of oscillation of the work-head and contains the axis of the ring. Instead of an oscillating work-head, an oscillating grinding-wheel or ring may be employed.