GB1231302A - - Google Patents

Abstract

1,231,302. Bakers' ovens. M. E. TILLANDER and A. B. PERSSON [trading as TI-PE ELMEKO, TILLANDER AND PERSSON]. 15 July, 1969 [31 July, 1968], No. 35481/69. Heading A2A. A bakers' or similar oven of the kind having an oven chamber adapted to receive a rack 10 loaded with goods to be treated, and having at the top of the oven a rotatable or reciprocable driver member adapted to be releasably engaged by the rack to impart to the latter a rotary or reciprocatory motion, includes an arrangement whereby the driver member is shiftable between a lower position for bringing the rack and driver member into engagement with each other, with the rack still supported by the floor of the oven chamber, and an upper position in which the rack is freely suspended from the driver member. A rotatable driver member 14 is shown, rotation being effected by a shaft 17 which is driven via a pulley 23 and is also axially slidable, A cylindrical cam 22 is fixed to the top plate 25 of the oven and is engaged by rollers carried by a collar 21 which is rotatable about the axis of the shaft 17 by a lever arm 27 connected as by a link with the door of the oven. The arrangement is such that when the door is opened the rollers carried by collar 21 rest in two low cam segments of the cam 22 and the, driver member is in its lower (chain-line) position which allows a rack to be wheeled into the oven to position engagement flanges 16 on the rack just above flanges 15 on the driver member. The door is now closed, causing rotation of the collar 21 whose rollers consequently ride up sloping cam segments of the cam 22 to high cam segments, causing the pulley 23 and shaft 17 to be raised, so that the driver member is lifted to its upper (full-line) position during which the flanges 15 and 16 engage and the rack 10 is thereby lifted off the oven floor. When the door is nearly closed, it actuates a switch which energizes a motor driving the pulley 23, so that the rack 10 is rotated until the door is reopened, whereupon the driver member is lowered to allow the rack 10 to be wheeled out of the oven chamber. Instead of a cylindrical cam 22 and rotatable collar 21, a toggle linkage 32, 34, Fig. 5, may be used, the pivotal connection 38 of the linkage being connected to the oven door by a link 28A whereby upon closure of the oven door forces apart the ends of the toggle links which are pivoted at 33, 35 to collars 21A, 36, the latter of which is supported on the top plate 25 of the oven by a thrust bearing 37, while a second thrust bearing 24 is interposed between the collar 21A and pulley 23. Instead of a toggle linkage, a single link, having its lower end provided with a roller which rolls on the top plate 25 of the oven, may be used (Fig. 7, not shown). The oven is provided with a fan 11 for circulating hot air around and through the oven chamber as indicated by the arrows (Fig. 1).