GB476257A - Gear testing apparatus - Google Patents

Abstract

476,257. Gauging toothed gears. PRETTY, H. J. June 6, 1936, No. 15882. [Class 106 (ii)] Relates to apparatus in which two meshing gears are mounted to revolve respectively with rotary discs of the same ratio which have their peripheries flexibly connected to moving members which move synchronously while there is no variation and at different speeds while there is variation, and consists in forming the members as parallel moving slides carrying cooperating parts of an indicator. A base block 11 has a transverse slot 12 in which are adjustably mounted upright pins upon which are sleeves 14, 14 fast with rotary discs 1.5, 15. The gear pair to be tested 16 are mounted above the discs and secured by nuts 17. The gear ratio is the same as that of the discs 15. Either of the gears may be a master. To the periphery of each disc is secured a flexible steel strip 18, the other end of which is secured to a slide 19. The slides 19 are mounted on balls 20 working in grooves 21. The strips 18 are kept taut by weights 22 flexibly connected to the slides 19. A stationary scale 25 is secured to one slide 19 and co-operates with a long pointer 26 pivoted at 27 to a bracket 28 fast on the slide. Engaging the pointer 26 near its pivot is the lever 29 fulcrumed in a spring blade 30 fast on the slide and pivotally connected at 31 to a block 32 fast on the other slide. As the gears are rotated if there is no variation in the angular velocities of the gears, the two slides will travel equally and the reading remain at zero. Any variation between the gears will cause one slide to move relatively to the other when the indicator will give a reading.