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US 4,567,789 AGranted
Method and apparatus for changing speed using a differential band
OwnerDonald F. Wilkesinventor
Life of this patent
Estimating the term…
Abstract
A transmission using an endless metal band provides an infinitely variable output velocity for an essentially constant input velocity. The transmission can be controlled to give both forward and reverse directions, through zero output speed. A multi-layer band can be used for greater torque transmission.
Claims18
A transmission for generating an infinitely variable speed output from a constant speed input comprising:
- a rotationally fixed structural means for mounting the transmission;
- input means for delivering a generally constant speed input to the transmission;
- output means for extracting a variable speed output from the transmission, a portion of the output means being carried by a portion of the input means;
- endless metal band means having a reflexively curved portion, a circumferential portion engaging the structural means and a lobe circumferentially moveable by the input means, and being operable to determine the variable output speed;
- and
- control means carried by the structural means and operable to regulate the endless metal band means.
3 more elements
A transmission for generating an infinitely variable speed output from a constant speed input comprising:
- a rotationally fixed structural means for mounting the transmission;
- input means for delivering a generally constant speed input to the transmission;
- output means for extracting a variable speed output from the transmission;
- endless metal band means engaging the structural means, engaged by the input means, and operable to determine the variable output speed;
- control means carried by the structural means and operable to regulate the endless metal band means;
- wherein the input means includes a central shaft coaxially mounted with a centerline of the transmission and an orbiting shaft mounted generally parallel to the central shaft but radially spaced therefrom;
- wherein the output means includes a central roller rotatably mounted on the central shaft and an orbiting roller rotatably mounted on the orbiting shaft;
- and
- wherein the endless metal band means partially wraps the central roller, and is pinched between the central roller and the orbiting roller such that the band means causes the central roller and the orbiting roller to rotate as the orbiting shaft is driven.
6 more elements
A method of changing rotational speed comprising the steps of:
- constraining an endless metal band having a predetermined length in an envelope having a circumference less than the predetermined length such that a lobe and a reflexively curved portion are displaced from the envelope;
- restraining an arcuate portion of the endless metal band from movement relative to the operating envelope;
- applying an input torque to the lobe of the endless metal band with an orbiting support carrying a rotatable element;
- driving the rotatable element by frictional engagement with the endless metal band;
- and
- extracting power from the rotatable element.
3 more elements
A speed changing device comprising:
- a generally cylindrical rotationally fixed envelope having a circumferential length;
- band means disposed in the envelope for partial engagement therewith and having a length which exceeds the circumferential length such that the band means defines an arcuate portion engaging the envelope, a lobe, and a reflexively curved portion, the arcuate portion having a length which is substantial in relation to the circumferential length of the envelope;
- input means operable to move the lobe circumferentially around the envelope so that the band means moves at least radially with respect to the envelope;
- and
- output means driven by the moving lobe for providing an output speed.
2 more elements
Dependencies are inferred from the claim text.