US 4,800,768 A · Power transmission apparatus

Abstract

A transmission means for transmitting power between input and output drives in which a rack and pinion gear assembly and a cam adjacent the pinion cooperate with the drives to provide a variable gear ratio therebetween. The gear assembly includes inner and outer gear rack pairs, in which such gear rack pair has oppositely facing toothed rack portions which are spaced apart sufficiently to receive the pinion gear and cam therebetween, with an outer surface of the cam adjacent at least one of the oppositely facing toothed rack portions. Resilient connectors interconnect the end portions of each pair of toothed rack portions to as to permit limited resilient movement between the rack portions of each pair. A rotor engages the rack pairs to transmit that power therebetween. Preferably, a gear ratio changer can vary spacing between input and output axes in such a direction as to provide a favourable change in effective radius of action of the drive in addition to the gear ratio resulting from the rack and pinion gear assembly.

Claims25

Dependent claims

A power transmission apparatus having:

(a) a body,
(b) a pinion gear mounted for rotation about a pinion axis relative to the body,
(c) a cam means having curved inner and outer surfaces, the cam means and the pinion gear being mounted for relative rotation therebetween,
(d) inner and outer gear rack pairs, each gear rack pair having oppositely facing toothed rack portions which are spaced apart sufficiently to receive the pinion gear and cam means therebetween when the pinion gear fully engages teeth of at least one of the toothed rack portions and the outer surface of the cam means is adjacent at least one of the oppositely facing toothed rack portions, the toothed rack portions of each pair having oppositely disposed end portions,
(e) resilient connecting means for interconnecting the end portions of each pair of toothed rack portions, so as to permit limited resilient movement between the toothed rack portions of each pair,
(f) a rotor mounted for rotation about a rotor axis, the rotor having engaging means for sliding contact with the resilient connecting means of said first and second gear rack pairs, so as to transmit power therebetween.

3 more elements

A power transmission apparatus having:

(a) a body,
(b) a pinion gear mounted for rotation about a pinion axis relative to the body,
(c) a cam means having curved inner and outer surfaces, the cam means and the pinion gear being mounted for relative rotation therebetween,
(d) inner and outer gear rack pairs, each gear rack pair having oppositely facing toothed rack portions which are spaced apart sufficiently to receive the pinion gear and cam means therebetween when the pinion gear fully engages teeth of at least one of the toothed rack portions and the outer surface of the cam means is adjacent at least one of the oppositely facing toothed rack portions, the toothed rack portions of each pair having oppositely disposed end portions,
(e) resilient connecting means for interconnecting the end portions of each pair of toothed rack portions, so as to permit limited resilient movement between the rack portions of each pair,
(f) a rotor mounted for rotation about a rotor axis, the rotor having engaging means for cooperating with the first and second gear rack pairs, so as to transmit power therebetween,
(g) the engaging means of the rotor including four track surfaces disposed as two pairs of oppositely disposed parallel surfaces forming a generally square configuration,
(h) the gear rack pairs being disposed at right angles to each other so that one rack pair extends between a respective pair of the oppositely disposed track surfaces, the connecting means of each gear rack pair engaging the adjacent track surface for movement therealong.

5 more elements

Dependencies are inferred from the claim text.

Power transmission apparatus

Life of this patent

Power transmission apparatus

Life of this patent

Abstract

Claims25