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US 4,117,746 AGranted
Orbital drive mechanism
AssigneeCompudrive Corporation
InventorMichel A. Pierrat
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AssigneeCompudrive Corporation
InventorMichel A. Pierrat
Estimating the term…
In a compact high-torque mechanical speed changer of the type in which different relative speeds may be realized through substitution of different cooperating planet and sun gear components one of which has teeth in the form of lobes of continuous substantially epitrochoid curvature and the other of which has circularly-curved teeth differing in number by one, orbiting motions associated with angular movements are resolved and angular motions are developed about a non-orbiting axis by way of a unique "zero-velocity" transmission plate having peripheral circular-sided openings cooperating with an array of circular pins, rollers or the like. The lobed gear and the transmission plate are advantageously fixed together for orbital motion in response to rotation of a shaft eccentric, and are of about the same diameter, and their cooperating toothed companions are preferably of the type involving discrete roller-pin teeth, and are of the same diameter. These cooperating sets are substantially identical in important dimensional respects, and portions can therefore be changed to effect different speed ratios, with the same counterweighting serving to offset eccentricities. The changer housing and interior mountings for gear combinations accommodate different sets, as desired, to yield various relative speeds of the relatively-rotatable parts, and the transmission plate orbiting component may advantageously be replaced by a lobed component to extend the range of speed ratios which are available from one basic size of speed changer.
An orbital drive mechanism comprising two orbiting elements, one of which has peripheral surfaces acting as gear teeth and the other of which has peripheral open recesses which promote angular coupling isolated from orbital motion, means supporting said two elements for movements together eccentrically about an axis, two non-orbiting elements concentric with said axis, one of said non-orbiting elements being nested with said one of said orbiting elements and having peripheral surfaces acting as gear teeth which differ in number from the number of said gear teeth of said one of said orbiting elements, the other of said non-orbiting elements having peripheral surfaces of substantially circular curvature disposed within said peripheral open recesses of said other of said orbiting elements, margins of said peripheral open recesses being shaped substantially as arcs of a circle having a diameter equal substantially to the diameter of said circular curvature plus twice the eccentricity of said orbiting elements about said axis, and means restraining one of said non-orbiting elements from following angular movements of the orbiting element meshed therewith.
An orbital drive mechanism comprising an orbital element having epitrochoidal gear teeth and surfaces of substantially circular curvature which promote angular coupling isolated from orbital motion the center of said cylindrical recesses being on a diameter equal to or greater than the mean diameter of the peripheral gear teeth on said orbiting element, means supporting said orbital element for movement eccentrically about an axis, and two non-orbiting elements concentric with said axis, one of said non-orbiting elements being nested with said gear teeth and having surfaces acting as gear teeth which differ in number from the number of gear teeth of said orbiting element, the other of said non-oribiting elements having surfaces of substantially circular curvature meshed with said surfaces of said orbiting element, the circular surfaces of said orbiting element being shaped substantially as arcs of a circle of less than 360.degree. with diameters equal substantially to the diameters of the surfaces of the other said non-orbiting element plus twice the eccentricity of said orbiting element about said axis.
An orbital drive mechanism comprising an orbiting element having peripheral epitrochoidal gear teeth, means supporting said orbiting element for movement eccentrically about an axis, and two non-orbiting elements concentric with said axis, the first of said two non-orbiting elements being nested with said gear teeth and having surfaces acting as gear teeth which differ in number from the number of gear teeth of said orbiting element, a set of laterally extending cylindrical pins which promote angular coupling isolated from orbital motion on one of said orbiting element and the second said non-orbiting element and a set of cylindrical recesses on the other of said orbiting element and the second said non-orbiting element, said cylindrical recesses meshing with said pins, the diameter of said recesses being equal substantially to the diameter of the pins plus twice the eccentricity of said orbiting element about said axis.
Dependencies are inferred from the claim text.