Patent GB-819801-A (GB)
Title: Improvements in or relating to heating and ventilating devices for vehicles
Inventor: LAMBURN ALAN SALISBURY
IPC: B60H1/00
Filed: 1955-04-01
Abstract: 819,801. Ventilating vehicles. SMITH & SONS (ENGLAND) Ltd., S. April 3, 1956 [April 1, 1955], No. 9549/55. Class 137 A heating and ventilating unit for a vehicle comprises a box-shaped housing 1, the front wall 2 of which communicates, immediately behind a dashboard with a chamber, not shown, supplied with warm air, and has two side openings 3 controlled by flap valves 5, 6, and a central opening 4 leading to an enclosed compartment 8 for a radiator matrix 7 which is connected through pipes 14 to the engine liquid coolant system, the rear wall of the compartment 8 being provided with three outlet openings. The outer two of the latter are controlled by oneway valves 11 each consisting of a light rectangular plate which is hinged along its upper edge and has its inner face covered with a thin layer, e.g. of foamed plastic. Each valve 11 is spring urged to close its associated opening in order to prevent air from re-entering the compartment 8 when a fan 10, associated with the centre opening in the rear wall of the compartment 8 and driven by an electric motor 12 which assists the flow of air through the matrix, is switched on. Two outlet openings 17 in the base of the housing 1 each communicate with an outlet duct 18 which leads to the vehicle interior and has a branch duct 20 connected, e.g. to a demisting nozzle, not shown. A butterfly valve 21 rotatable on a shaft 22, in each duct 18, is connected by a cable 23 to a pivoted plate 26, Fig. 7, manually operable by a lever 25. The plate 26 carries a spring plunger 27 for engagement with one of three notches (i), (ii), and (iii) formed on the periphery of a locking plate 29 to respectively either incline the valve to close the duct 18, and the branch duct 20, position the valve 21 parallel to the longitudinal axis of the duct 18 so that it and the branch duct 20 are both open, or incline the valve, Fig. 6, at a similar angle in the oppsite rotary sense to the position (i) so that the branch duct 20 is open and the main duct 18 is closed. A plate with a cam surface 30 and riveted to the plate 26 operates the plunger of an electric switch 31 included in the supply lines to the electric motor 12 to close a circuit when the plate 26 is engaged in positions (ii) and (iii). The flap valves 5, 6, secured to a common shaft 47 and each having a bent portion 16 to direct the cold fresh air away from the radiator compartment 8, are movable by a manually operable lever 32 attached to a pivoted plate 33. The latter carries a spring plunger 34 which co-operates with notches A, B, E, F, in the periphery of a plate 39. A plate with a cam surface 36 riveted to the plate 33 operates the plunger of an electric switch 37 which is connected in series with the switch 31 to be closed in positions A and F of the plate 33 and open for positions B to E. The centre wire of a cable 38, clamped to the plate 39, is attached to the plate 33, the other end being connected to a crank lever 40, Fig. 3, on a shaft carrying on its other end a rotatable central member 41 having internal cam surfaces 42, 43. A follower 44, projecting from one arm of a bell-crank lever 45, pivoted to the bearing yoke of the shaft for the con-- trol member 40 is actuated by the cam surface 42, a coil spring 46 linking the other arm of the bell-crank lever 45 to the flap valve 5. Another cam follower 48 is actuated by the cam surface 43 to regulate a valve 15 which controls the supply of water to the matrix 7, an axially displaceable rod co-operating with the cam surface 43. The action of the device is as follows:-with the lever 32 in position A, air is drawn through the heated matrix 7 by the fan 10, no cold air entering through the flap valves 5, 6, and the outflow of air having a maximum temperature. In position B, air is forced through the heated matrix by ram pressure, no cold air entering through the valves 5, 6 and outflow having a maximum temperature. Between the positions C and D there is more, or less constant flow of air forced through the heated matrix dependent upon the car speed, increasing quantities of cold air entering through the flap valves by ram pressure to steadily decrease the temperature of the outflow air. In position E, air is forced through the cold matrix by ram pressure air also entering through the flap valves, and the outflow air having a minimum temperature. In position F, air is drawn by the fan through the cold matrixno cold air entering through the flap valves. Outflow has a minimum temperature. Adjustment of the lever 25 has the following results:-in position (1) the motor- 12 is switched off and the outlets from the ducts are closed; in position (ii) the outflow is directed almost entirely to the car interior, but a small proportion is directed to the windscreen; in position (iii) the outflow of air is directed solely to the screen nozzles for demisting and defrosting. Specification 772,292 [Group XXIX] is referred to.