GB885664A - Improvements relating to flow machines - Google Patents

Abstract

885,664. Transverse-flow blowers. LAING, N., and ECK, B. Dec. 6, 1957 [Dec. 7, 1956 (2); Dec. 31, 1956 (2)], No. 29472/61. Divided out of 885,663. Class 110 (1). In a transverse-flow machine for inducing a flow of fluid and comprising a cylindrical rotor having blades extending longitudinally of its rotational axis and disposed in a ring thereabout, and guide means co-operating with the rotor to set up a flow which traverses the blades twice in a direction transverse to the rotor axis, at least a part of each blade is of variable angle or profile, the variation being effected cyclically during each revolution of the rotor. The guide means may be a stationary guide body external to the rotor and inducing a free cylindrical vortex in the flow through the rotor as described in Specification 876,611. Fig. 4 shows the rotor of a transverse-flow blower in which blades 42 are pivotally mounted between end discs 40. The blades are connected to rods 44 extending slidably through guideways in a member 45 mounted for rotation about an axis eccentric to the rotor axis whereby the blade angles are varied cyclically during each revolution of the rotor. In a modification the blades are flexible and their leading and trailing ends are linked independently to two points each eccentric to the rotor axis. In the rotor shown in Fig. 6, each blade 60 is turned through about 180 degrees as it crosses a diametral plane 63 so that the bulbous edge 60a is the leading edge during both traversals of the fluid. In addition, each blade may be formed in three sections, the leading and trailing sections being angularly movable relative to the central section to reverse the camber of the blade. In Fig. 5, each blade 50 is oscillated by means of a push rod 52 sliding in a self-aligning guideway 54 and carrying a roller 56 engaging a stationary cam 57. Alternatively, the push rod is connected to a piston 507 slidable within a cylinder 508 connected by pipes to a chamber 512 whereby liquid is displaced through the pipes to oscillate a vane 511 and hence a blade 501. In a further embodiment, Fig. 11, a rocker arm 113 pivoted about the same axis 114 as the blade 115 carries an odd number of idler pinions 112 meshing with a gear-wheel 116 secured to the blade and meshing also with a central fixed cam-shaped gear-wheel 110 having the same number of teeth as the gear-wheel 116. The position of gear-wheel 110 may be adjustable. Each blade may be divided into separate leading and trailing parts independently pivoted about a common axis and independently turned about the axis by separate mechanisms each similar to that shown in Fig. 11. In a modification of the Fig. 11 arrangement, the cam-shaped stationary gear-wheel is replaced by a circular gear-wheel which is rotated to transmit the desired movement through a single idler pinion to the gear-wheel secured to the blade. Fig. 13 shows a blade in which the main portion 130 is fixed to the rotor, the trailing end of the blade comprising a flap 132 which is oscillated cyclically during each revolution of the rotor to cause a corresponding deflection of a jet of fluid issuing from the interior of the portion 130 through a nozzle 134, thereby causing a corresponding variation of the lift and the effective angle of incidence. In the embodiment shown in Fig. 10, an eccentric pin 100 carried by the rotor works in an oversize hole in a slide 102 which slides in a curved guideway 103 in a larger slide 104 which slides in a straight guideway in the direction of the arrows 104a. A lever 105 is connected to the slide 102 to control the blades directly or indirectly.