| 摘要 |
1528653 Temperature-responsive actuating elements QUINTON HAZELL (HOLDINGS) Ltd 28 Jan 1977 [13 Feb 1976] 05799/76 Heading G1D [Also in Division F1] The blades 18 of a fan are varied in pitch by a temperature sensitive actuator comprising a plastics coil 28 within a support 25 which exerts a radial force on the coil throughout its length so that relative thermal expansion or contraction between the coil and its support causes adjacent turns of the coil to move relative to each other, this in turn causing rotation of an element, e.g. the support 25 relative to the fan hub to vary the pitch of the blades. The coil is attached at one end to the support 25 by a lug 30, the other end abutting, during expansion, a stop 29 secured to the fan hub, rotation of the support (against force in springs 33), due to expansion or contraction of the coil causing rotation of the blades by means of projections 36 on support 25 which engage levers 38 integral with blade roots 20. The coil may be helical (as shown), frusto-conical or spiral and in one modification the support is fixed, the coil rotating instead a ring for effecting pitch change. In another modification, the coil is anchored intermediate its ends, the relative motion of its ends being utilized to operate the pitch change mechanism; and in a further modification the support is in the form of a helical tube. Reference is made to applying the actuator to operate a radiator blind. |
