| 摘要 |
384,511. Motor driving-arrangements. BOSCH AKT.-GES., R., 4, Militõrstrasse, Stuttgart, Germany. March 21, 1932, No. 8303. Convention date, July 27, 1931. [Class 35.] Motors, cooling.-A portable machine having a high speed rotary tool comprises an electric motor 1 which rotates when running light at a speed of from 8000 to 12000 r.p.m. and whose shaft 4 carries a pulley 5 connected by a belt 22 to a pulley 12 on the tool spindle 9 which rotates at a speed of from 30000 to 50000 r.p.m: The pulley 5 serves as a flywheel to compensate for variations of load on the motor and is also provided with a fan 6 to draw air through apertures 19, 20 in the casing 18 and bearing supports 3, 2 respectively and to deliver it around the tool spindle 9, to cool it and blow away swarf from the tool 14. The spindle 9 is carried in elongated roller bearings 13 in a support 8 which is adjustably secured to an extension 7 of the bearing support 2. Adjustment to vary the tension of the belt is effected by a screw 11 and locking by a cap nut 10 screwing on the support 8. The apparatus is enclosed by two covers 17, 18 formed of insulating material, the cover 17 having an extension 21 surrounding the tool spindle 9 and support 8. A handle 15, carrying a controlling switch 16 for the motor, is secured to the support 7 in line with the tool spindle and is provided with a hole to give access to the cap nut 10. The machine may be secured to the slide rest of a lathe and a belt drive to the tool spindle may be provided at both ends of the motor shaft. One end of the motor shaft may be constructed as a holder for a drill, milling-cutter or similar rotary tool and the holes 10 may be covered by wire gauze. |
