GB848275A - Automatic gear gauging apparatus - Google Patents

Abstract

848,275. Gear gauging and sorting apparatus; indicating output of machines. NATIONAL BROACH & MACHINE CO. April 11, 1958, No. 11593/58. Classes 106 (2) and 106 (4). [Also in Group XXII] Gear gauging apparatus adapted to operate with a machine for finishing gears comprises means 10, 12, to gauge the finished size of the gear and the helix angle of its teeth, means for rejecting gears which are defective by reason of size or of helix angle errors, means for counting the rejected gears, and means for initiating arrest or adjustment of the finishing machine when a predetermined number of gears are rejected for the same error or when the total number of gears rejected for any error reaches at any instant a predetermined percentage of the total number of gears gauged up to that instant. Gears to be tested travel along a shoot 66 from the finishing machine (not shown) and mesh with a rotating master gear 10 and a master gear 12 fixed against rotation. The gear 12 is mounted on an arm 34, 36, pivoted about an axis 54 for movement in a vertical plane and also pivoted about an axis 38. Movement of the arm 36 about the axis 38 indicates whether the helix of the gear being tested is correct, displaced to the left, or to the right; similarly, movement in the vertical plane indicates whether the diameter of the gear is undersize, oversize, or within a specified tolerance range. If the gear is correct both as to helix angle and diameter, it moves on, after gauging, over a pair of trap doors 78, 80 on to a conveyer or receptacle (not shown). If the gear is undersize it is regarded as waste and drops through the trap door 80, opened by a solenoid B, into a receptacle or conveyer. If the gear is oversize, then regardless of its helix angle it is regarded as salvageable and is allowed to fall through the trap door 78 which is operated by a solenoid A. The pivotal movement of the arm 36 about the axis 38 allows the master gear 12 and the work gear to mesh to the full depth of their teeth and hence the gauging of the diameter is unaffected by variations in helix angle. An electromechanical circuit is described which acts to stop the gear-finishing machine should three consecutive gears exhibit the same fault or if a certain percentage of the gears produced is incorrect. Alternatively, the gear-finishing machine may be automatically adjusted if the faults are in the diameters of the gears (Group XXII). Electric circuits for carrying out these operations are described.