GB949595A - Improvements relating to air-conditioning installations on vehicles - Google Patents

Abstract

949,595. Ventilating vehicles. DAIMLERBENZ A.G. July 18, 1961 [July 27, 1960], No. 26048/61. Heading F4V. A vehicle ventilating system includes a fresh air duct 6 which contains a heater 7, a fan 8 and a flap valve 10. The heater 7 has a source of heat independent of the vehicle engine which can be automatically switched on and off by a switch 38 independent of the ignition switch 37. A second fresh air duct 17 and recirculation duct 20 enter a common duct 25 which then forks into ducts 26 and 27 entering the interior of the vehicle. A third fresh air duct 1 supplies a demister duct 11 and a duct 12 entering into the passenger compartment. The evaporator 29 of a refrigerating system is used as a cooler in duct 26. Heat exchangers 2 and 30, supplied with engine coolant heat the air in ducts 1 and 27. A temperature selector 45 has three operating positions: "heating," " ventilating " and "cooling"; and is shown in the heating position. When the engine is first started, with the coolant below the required temperature for heating, heating is supplied by the independent heater 7. A current is supplied to the heater 7 from the battery 40 via the lower limb of the ignition switch 37, contact arm 47 of the selector 45, arcuate contact 50, switch 69 of the two-pole switch 71 and lines 43 and 42. When the engine coolant has reached the desired temperature, say 25‹ C., a thermostat 58 operates switch 71 and piston valve 57. A twospeed blower switch 72 is supplied via line 68 from switch 71 and supplies current to the two fan motors 3 and 24, when the current supply to the independent heater is cut. Valve flaps 5, 31, 21 and 19 are operated hydraulically via slide valves 57, 55 and lines 63, 64 and 65. Electrically heated temperature sensing means 23 is supplied with current via the rheostat 49 of the selector 45 to control the amount of hot engine coolant entering heat exchangers 2 and 30. Extra heat for demisting is obtained by pulling rod 33, thereby closing switch 36 which cuts in the independent heater 7. " Ventilating " is obtained with contact 47 in the midway position between the arcuate contacts 50 and 52 of the selector 45. In this position, no current is supplied to either the electrically driven engine coolant pump 61 or the compressor 62 of the refrigerating system. " Cooling " is obtained with contact 47 across the arcuate contact 52 and rheostat 51. In this position, slide valve 55 shuts off line 65, and only flap valve 19 is actuated hydraulically via line 64 and valve 57. With flap valve 5 closed, the circuit to earth of fan motor 3 is incomplete so that only fan motor 24 operates. Air is directed over the cooler 29 and the electrically heated temperature-sensitive means 28 which controls the amount of refrigeration. The independent heater 7 is electrically heated or may be an electrically ignited burner supplied with fuel from the storage tank of the vehicle.