Hydraulic rotary actuator
OwnerWilliam O'Harainventor
Life of this patent
Estimating the term…
Abstract
A shaft extending along a longitudinal axis has fluid channels that increase and decrease pressure in chambers formed between the interior ends of curved pistons and adjacent closed ends of curved chambers within which the pistons reciprocate as the chamber pressure increases and decreases. The chambers and pistons are in separate cylinder block segments extending outward from opposing sides of the shaft. Each segment may have two sides extending along radial planes and joined by a curved outer surface. Pistons may be provided in pairs and have an interior piston end of each piston in a different cavity in different segments. Exterior ends of each piston in a pair of pistons are connected to a piston connector that extends inwardly from a housing so the housing rotates with the pistons.
Claims19
A fluid actuated, rotary actuator, comprising:
- a shaft having first and second opposing ends with a longitudinal axis and a cylinder block intermediate the first and second ends;
- the cylinder block having at least one segment extending along a length of the axis and subtending an arc of less than 340° about the longitudinal axis, the at least one segment having an outer surface forming a portion of a cylindrical surface centered on and extending along the axis;
- each segment having first and second sides facing opposing circumferential directions about the longitudinal axis;
- each segment having at least one toroidal cavity curving around the longitudinal axis, each toroidal cavity located in the same general plane orthogonal to the longitudinal axis;
- each toroidal cavity having a closed end internal to the at least one segment and an open end opening onto one of the first or second sides of the at least one segment;
- sealing rings around the open end of each toroidal cavity which opens onto one of the first or second sides of the segment;
- at least one curved piston, each piston being curved at the same radius as each toroidal cavity and having a cross section and sized and configured to reciprocate along the first circumferential length into and out of the opening and sealing ring;
- a housing having a cylindrical inner surface connected to the first and second ends of the shaft by bearings;
- the housing having a first inward extending connector connected to the exterior end of each piston so the housing rotates as the piston(s) move along the toroidal cavity in which each piston is located;
- a separate fluid passage extending from an outer surface of the shaft to each of the chambers.
A fluid actuated, rotary actuator, comprising:
- a housing having a cylindrical inner surface of diameter D and extending along a longitudinal axis;
- a shaft having first and second opposing ends and extending along the longitudinal axis inside the housing;
- first and second bearings on respective first and second ends of the shaft and interposed between the shaft and housing so the shaft and housing rotate relative to each other about the longitudinal axis;
- a cylinder block on the shaft having first and second segments each having an outer surface forming a portion of a cylinder of slightly smaller diameter than diameter D, each segment extending along an arc relative to the longitudinal axis, each segment having circumferentially opposing faces;
- each segment containing two toroidal cavities each curving about the longitudinal axis and having a d in a radial plane along the longitudinal axis, each toroidal cavity having an internal closed end and an open end on one of the faces of the first and second segments, the toroidal cavities aligned in a first plane orthogonal to the longitudinal axis;
- first and second pairs of curved pistons having a cross section to fit into the opening of toroidal cavity slightly less than d in a radial plane orthogonal to the longitudinal axis and configured to reciprocate along the toroidal cavities and about the longitudinal axis, each pair of pistons having a first and second piston each with an interior end and an exterior end, each first and second piston of each pair of pistons located in a different one of the toroidal cavities in a different segment;
- a first connector extending inward from the housing between two of the faces of the segments and connected to the exterior end of the first pair of pistons so the pistons rotate with the housing;
- wherein each piston rotates about the longitudinal axis within a different toroidal cavity with a different chamber defined by each interior end and the closed end of the cavity in which the piston rotates;
- and
- a separate fluid passage in fluid communication with each chamber.
Dependencies are inferred from the claim text.