GB831270A - Means for heat treating gears by high frequency induction heating - Google Patents

Abstract

831,270. Induction heating. DELAPENA & SON Ltd. April 13, 1956 [April 15, 1955], No. 10962/55. Class 39(3) The apparatus for heat treating a toothed convex surface of an article by high frequency induction heating, described in Specification 831,269, includes adjustable means whereby the apparatus can deal with helical gears of different helix angles as well as with gearwheels having straight spur teeth. A helical gear wheel being heat treated is caused to travel past an inductor by a device 36 comprising a pinion 37 secured to a gearwheel mounting shaft 14, the pinion engaging a toothed rack 38 horizontally slidable in a crosshead 19 which moves axially with the mounting shaft. An arm 39 carries a roller 40 which engages in a slot 45 diametrically formed in a face 42a of a drum 42 journalled for adjustment about a horizontal axis. The drum is provided with a graduated dial plate 41 and is angularly adjustable by a manually rotatable worm 44 which engages gear teeth 43 on the drum. With the slot 45 set at the appropriate angle for a helical gearwheel being treated, upward or downward movement of the mounting shaft 14 causes vertical movement of the rack 38 and its roller 40, the rack and roller also being moved transversely as a result of the movement of the roller in the slot 45 set at an angle. The pinion 37 and shaft 14 are thus rotated and each tooth space of the gearwheel is positively guided past the inductor. A lock pin for engaging in a series of tapered holes enables the drum 42 to be set rapidly to the position in which the slot 45 is vertical, i.e. when a gearwheel having straight spur teeth is to be treated and to positions frequently used for helical gearwheels. Instead of the rack and pinion device, the required movement may be obtained by means of a flexible metal tape or tapes wound or unwound on a drum. Specifications 714,488, 775,463 and 813,113 also are referred to.