# US 10,767,669 B2 · Rotary piston type actuator with a central actuation assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,767,669 B2 - Document ID: US10767669B2 - Status: Granted - Kind: B2 - Application number: 15/807,184 - Filed: 2017-11-08 - Published: 2018-03-08 - Granted: 2020-09-08 - Earliest claimed: 2013-02-27 - Assignees: Woodward, Inc. - Applicants: Woodward, Inc. - Inventors: Joseph H. Kim; Robert P. O'Hara; Shahbaz H. Hydari; Pawel A. Sobolewski - Web page: https://patentgrep.com/patent/US10767669B2 ## CPC - F15B 15/02: Mechanical layout characterised by the means for converting the movement of the fluid-actuated element into movement of the finally-operated member - F15B 15/125: {of the curved-cylinder type} - F15B: SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR ## Abstract A rotary actuator includes a housing, a rotor assembly rotatably journaled in said housing and including a rotary output shaft, a central actuation assembly including a central mounting point formed in an external surface of the rotary output shaft, said central mounting point proximal to the longitudinal midpoint of the rotary output shaft, a mounting assembly adapted for attachment to an external mounting connector of a mounting surface of an aircraft structural member, and an actuation arm removably attached at a proximal end to the central mounting point, said actuation arm adapted at a distal end for attachment to an external mounting feature of an aircraft assembly to be actuated. ## Claims ### Claim 1 A rotary actuator comprising: a housing comprising a mounting assembly adapted for attachment to an external mounting connector of a mounting surface; a rotor assembly rotatably journaled in said housing and including a rotary output shaft; a central actuation assembly including a central mounting point formed in an external surface of the rotary output shaft, said central mounting point proximal to the longitudinal midpoint of the rotary output shaft, and a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotary output shaft; and an actuation arm extending through the radial recess and removably attached at a proximal end to the central mounting point, said actuation arm adapted at a distal end for attachment to an external mounting feature of a member to be actuated. ### Claim 2 (depends on 1) The rotary actuator of claim 1 wherein the mounting assembly comprises a radially projecting portion of the housing, said mounting assembly disposed about 180 degrees from the radial recess of the central actuation assembly, said mounting assembly adapted for attachment to an external mounting connector of the mounting surface. ### Claim 3 (depends on 2) The rotary actuator of claim 2, wherein the radially projecting portion of the housing is a radially projecting central portion of the housing. ### Claim 4 (depends on 1) The rotary actuator of claim 1, wherein: the housing defines a first arcuate chamber including a first cavity, a first fluid port in fluid communication with the first cavity, and an open end; the rotor assembly further includes a first rotor arm extending radially outward from the rotary output shaft; and the rotary actuator further comprises an arcuate-shaped first piston disposed in said housing for reciprocal movement in the first arcuate chamber through the open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, and a first portion of the first piston contacts the first rotor arm. ### Claim 5 (depends on 4) The rotary actuator of claim 4, wherein the housing further defines a second arcuate chamber comprising a second cavity, and a second fluid port in fluid communication with the second cavity; the rotor assembly further comprises a second rotor arm; and the rotary actuator further comprises an arcuate-shaped second piston disposed in said housing for reciprocal movement in the second arcuate chamber, wherein a second seal, the second cavity, and the second piston define a second pressure chamber, and a first portion of the second piston contacts the second rotor arm. ### Claim 6 (depends on 5) The rotary actuator of claim 5 wherein the central actuation assembly further includes a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotary output shaft, and wherein said actuation arm extends through the radial recess. ### Claim 7 (depends on 1) The rotary actuator of claim 1, further comprising a linear actuator mounted at a first end to the housing, and a second end mounted to a first rotor arm extending radially outward from the rotary output shaft. ### Claim 8 (depends on 1) The rotary actuator of claim 1, further comprising a rotary actuator comprising a stator mounted to the housing and a rotor coupled to the rotary output shaft. ### Claim 9 (depends on 8) The rotary actuator of claim 8, wherein the rotary actuator is one of a rotary piston type actuator, a rotary vane type actuator, or a rotary fluid type actuator. ### Claim 10 (depends on 8) The rotary actuator of claim 8, wherein the rotary actuator is an electromechanical actuator. ### Claim 11 (depends on 8) The rotary actuator of claim 8, wherein the rotary actuator comprises a linear actuator and a linear-to-rotary motion conversion assembly coupled to the rotor. ### Claim 12 (depends on 1) The rotary actuator of claim 1, wherein the housing is formed as a one-piece housing. ### Claim 13 (depends on 1) The rotary actuator of claim 1, wherein the external mounting feature is attached to one of an aircraft structural member or an external mounting connector of an external surface, and the mounting assembly is attached to the other of the aircraft structural member or the external mounting connector. ### Claim 14 A method of rotary actuation comprising: providing a rotary actuator comprising: a housing; a rotor assembly rotatably j ournaled in said housing and including a rotary output shaft; a central actuation assembly including a central mounting point formed in an external surface of the rotary output shaft, said central mounting point proximal to the longitudinal midpoint of the rotary output shaft, and a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotary output shaft; and an actuation arm extending through the radial recess and removably attached at a proximal end to the central mounting point, said actuation arm adapted at a distal end for attachment to an external mounting feature of a member to be actuated; energizing the rotor assembly; urging rotation of the rotary output shaft; urging rotation of the actuation arm; urging motion of the member to be actuated. ### Claim 15 (depends on 14) The method of claim 14, wherein the central actuation assembly further includes a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotor shaft, and wherein said actuation arm extends through the radial recess. ### Claim 16 (depends on 14) The method of claim 14, wherein the mounting assembly further comprises a radially projecting portion of the housing, said mounting assembly disposed about 180 degrees from the radial recess of the central actuation assembly, said mounting assembly adapted for attachment to an external mounting connector of a mounting surface. ### Claim 17 (depends on 14) The method of claim 14, wherein the radially projecting portion of the housing is a radially projecting central portion of the housing. ### Claim 18 (depends on 14) The method of claim 14 wherein the central actuation assembly further includes a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotary output shaft, and wherein said actuation arm extends through the radial recess. ### Claim 19 (depends on 14) The method of claim 14, further comprising a rotary actuator comprising a stator mounted to the housing and a rotor coupled to the rotary output shaft. ### Claim 20 (depends on 19) The method of claim 19, wherein the rotary actuator is one of a rotary piston type actuator, a rotary vane type actuator, or a rotary fluid type actuator. ### Claim 21 (depends on 19) The method of claim 19, wherein the rotary actuator is an electromechanical actuator. ### Claim 22 (depends on 19) The method of claim 19, wherein the rotary actuator comprises a linear actuator and a linear-to-rotary motion conversion assembly coupled to the rotor. ### Claim 23 A rotary actuator comprising: a housing; a rotor assembly rotatably j ournaled in said housing and including a rotary output shaft; a central actuation assembly including a central mounting point formed in an external surface of the rotary output shaft, said central mounting point proximal to the longitudinal midpoint of the rotary output shaft, and a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotary output shaft; a mounting assembly adapted for attachment to an external mounting connector of a mounting surface of a structural member; and an actuation arm extending through the radial recess and removably attached at a proximal end to the central mounting point, said actuation arm adapted at a distal end for attachment to an external mounting feature of an assembly to be actuated. ### Claim 24 (depends on 23) The rotary actuator of claim 23 wherein the mounting assembly comprises a radially projecting portion of the housing disposed at a midpoint of the housing, said mounting assembly disposed about 180 degrees from the radial recess of the central actuation assembly. ### Claim 25 (depends on 23) The rotary actuator of claim 23, wherein: the housing defines a first arcuate chamber including a first cavity, a first fluid port in fluid communication with the first cavity, and an open end; the rotor assembly further includes a first rotor arm extending radially outward from the rotary output shaft; and the rotary actuator further comprises an arcuate-shaped first piston disposed in said housing for reciprocal movement in the first arcuate chamber through the open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, and a first portion of the first piston contacts the first rotor arm. ### Claim 26 (depends on 25) The rotary actuator of claim 25, wherein the housing further defines a second arcuate chamber comprising a second cavity, and a second fluid port in fluid communication with the second cavity; the rotor assembly further comprises a second rotor arm; and the rotary actuator further comprises an arcuate-shaped second piston disposed in said housing for reciprocal movement in the second arcuate chamber, wherein a second seal, the second cavity, and the second piston define a second pressure chamber, and a first portion of the second piston contacts the second rotor arm. ### Claim 27 (depends on 26) The rotary actuator of claim 26 wherein the central actuation assembly further includes a radial recess formed in an external peripheral surface of the housing proximal to the central mounting point of the rotary output shaft, and wherein said actuation arm extends through the radial recess. ### Claim 28 (depends on 23) The rotary actuator of claim 23, further comprising a rotary actuator comprising a stator mounted to the housing and a rotor coupled to the rotary output shaft. ### Claim 29 (depends on 28) The rotary actuator of claim 28, wherein the rotary actuator is one of a rotary piston type actuator, a rotary vane type actuator, or a rotary fluid type actuator. ### Claim 30 (depends on 28) The rotary actuator of claim 28, wherein the rotary actuator is an electromechanical actuator.