GB935934A - Improvements in or relating to air distributor fans - Google Patents

Abstract

935,934. Ventilating vehicles. S. SMITH & SONS (AUSTRALIA) PTY. Ltd. March 20, 1962 [April 6, 1961; Oct. 5, 1961], No. 10659/62. Class 137. [Also in Group XXVI] An air distributer fan comprises an outer casing with an air inlet port and at least two air-discharge ports, a rotationally adjustable volute casing within the outer casing having at least one air outlet mouth, a fan rotor within the volute casing adapted to draw air through the inlet port and deliver it into the volute casing for release through the outlet mouth, and discharge selector means whereby the volute casing may be rotationally adjusted to bring the mouth into register with either discharge port as desired, the air discharge ports being spaced closely enough to enable the air outlet mouth, at intermediate positions within the range of adjustment of the volute casing, to be partly in register with both discharge ports at the one time. In a heating system, Fig. 2, for a vehicle, air is sucked through a filter (not shown) and a duct 12 containing an electrical or hot water heater 14, into a centrifugal distributer fan unit 9, by a rotor 10, driven by an electric motor 11. The air passes into the fan unit 9 through an opening 20, Fig. 4, of substantially the same diameter as the rotor and is forced out of outlets 23 in a volute casing 22. The front wall of the latter (see particularly Fig. 2) has a flange (not shown) of a short shaft riveted or otherwise secured thereto coaxial with the rotor, the outer end of the shaft being provided with a knob for manual rotational adjustment of the volute 22. The volute 22 is restrained against rotation by frictionally gripping the shaft where it passes through the front wall of an outer casing 19. The latter is provided with four ports 15, 18 and 16, 17, the former two being ducted respectively to the passenger side and driver side de-mister outlets, whereas the latter two are ducted to the interior of the vehicle for heating purposes. By suitably adjusting the angular position of the volute 22, either of the respective port pairs in the outer casing 19 may be connected with all of the heated air supply or they may share it, as shown, in any proportion. The end walls of the casing 19 incorporating the ports 15-18 may be arcuate. The volute may have only one outlet which communicates with two or more ports in the outer casing. An alternative fan unit is shown in Fig. 6 in which the volute is viewed from the back. The volute is in two parts 35 and 36, having substantially flat front walls 42 and 37 respectively, two rearwardly directed side walls 43, 44 and 38, 39 and no back wall. The front wall 42 is substantially behind the front wall 37 but has an arcuate portion 42A which, by means of a step 48 and a slot extending between points 46, 47, is arranged in front of a corresponding portion 37A of the wall 37. A lever 30 pivoted at the bottom of the outer casing receives, in clearance slots, pins 52, 53 respectively fixed to walls 42 and 37. The head of the pin 53 is located in a recess in the wall 37 to avoid fouling the wall 42, and an arcuate clearance slot 55 for the pin 53 is provided in a bridge-piece 50 which is between the lever 30 and the walls 37, 42. An arcuate clearance slot 54 is provided in the wall 37 for the pin 52. Both parts 35, 36 are bolted at their centres to the bridge-piece 50 which is fixed to the front wall of the outer casing. Thus, movement of the lever controls the positions of the volute outlets 41, 45 relative to the two de-mister outlets 31, 32 and the heater outlets 33, 34, which are box-shaped with open backs and form outlets direct to the interior of the vehicle. Each part 35, 36 may instead have a rigid handle protruding forwardly from the walls 42, 37 through arcuate slots in the front wall of the outer casing, for independent adjustment. The front walls of the two volute parts may be reduced in size so as not to foul each other, in which case they may not overlap at all times. Here, the rearwardly directed walls of the two volute parts protrude circumferentially from the radial edges of the front walls, so that the proximity of the front edges of these protrusions to the front wall of the outer casing prevents excessive leakage from the volute.