Patent GB-1384466-A (GB)
Title: Cooking computer
IPC: G04C23/16
Filed: 1972-03-17
Abstract: 1384466 Determining cooking periods ROBERTSHAW CONTROLS CO 17 March 1972 [18 March 1971] 12761/72 Heading G4B [Also in Division H1] A device for determining the time for which a meat item is to be cooked comprises a rotatable knob 32, Fig. 1, and fixed scale 35 for entering the weight of the item, a rotatable knob 37 and fixed scale 40 for entering a K factor (dependent upon the type of meat and how well it is to be cooked and given by reference to table 41<SP>1</SP>), and a rotatable scale 42 (see also Fig. 2) linked by gear trains, Fig. 3 (not shown) to the knobs 32 and 37, so as to register at the "twelve-o'clock position" of window 43 the computed cooking time-a particular function of the inputs at 32 and 37. Once so positioned, the knobs 32, 37 and the scale 42 remain stationary until the knobs are manually reset after completion of the cooking of the meat item. During such cooking, a knob 45 bearing a reference line 44 is rotated clockwise by time clock mechanism (Fig. 2) so that line 44 indicates on scale 42 the period of the computed cooking time yet to run. The cooking time may be computed as A #weight + K, where A is a constant dependent upon whether the cooker to be used is electric or gas. This formula is appropriate when a constant cooking temperature of 325 F. is used throughout the computed cooking time period, except for a predetermined terminal portion of this period, during which terminal portion the temperature falls to a steady 170 F. The cut-back time at the beginning of this terminal portion is automatically determined by the time clock mechanism (Fig. 2). After making the required inputs at knobs 32, 37, the cooking period is begun by depressing knob 45, which connects the drive from an electrical timer motor 59 to the shaft 46 of the knob 45 and also closes a switch 79 to energize a control device of the cooker. Time clock mechanism.-The timer motor 59 continuously drives a pinion 57 which continuously meshes with gear teeth 56 on a plate 53, freely rotatable on shaft 46. Depression of -the knob 45 against the action of springs 80 and 83 engages a clutch plate 51-52, keyed to shaft 46, with the continuously driven plate 53. The depressed position of the knob 45 and hence the engaged condition of the clutch are held by a latch arm 98 (see also Fig. 4), pivoted about an axis 100 parallel to shaft 46 and urged by a spring 101 towards the shaft 46 so as to engage behind a step 70 carried thereby. The latch arm 98 is carried by an arm 94, secured to and rotatable with a bush 48, the angular position of which corresponds to the set angular position of the scale 42, which is carried by the bush 48. Hence the angular position of a pin 104, carried by latch arm 98, in relation to the initial position of a cam 61, rotatable with shaft 46, is dependent upon the computed time period. At cut-back time, the cam 61 trips the pin 104 to pivot the latch arm 98 clear of step 70. Springs 80, 83 then push shaft 46 outwardly until step 71 engages the latch arm; this outward movement of the shaft 46 results in switch 79 being reopened, but not in the disengagement of clutch 51-53. At the end of the cooking period, the cam 61 trips the pin 104 to pivot the latch arm 98 clear of step 71. Springs 80, 83 then push shaft 46 out to its original position before depression, wherein step 72 engages the latch arm, the clutch being disengaged. A spring 65, wound up during the cooking period, now returns the knob 45, shaft 46 and cam 61 to their starting positions.