Rotary actuator

Patent metadata

Field	Value
Publication number	US-2023383820-A1
Application number	US-202218073633-A
Country	US
Kind code	A1
Filing date	Dec 2, 2022
Priority date	May 27, 2022
Publication date	Nov 30, 2023
Grant date	—

Abstract

A rotary actuator includes a housing having a first end and a second end spaced from the first end along an axis. The housing defines a cavity extending circumferentially about the axis. An output shaft is arranged coaxially with the axis. The output shaft extends outwardly from the cavity through the first end. A drive system is disposed in the cavity and axially spaced from the first end. A gearbox is disposed in the cavity between the output shaft and the drive system. The gearbox is coupled to the drive system and the output shaft. A rotational controller is disposed in the cavity between the drive system and the second end. The rotational controller is configured to actuate the drive system to adjust an angular position of the output shaft.

First claim

What is claimed is:

1 . A rotary actuator, comprising:
a hollow housing including a first end and a second end spaced from the first end along an axis, the hollow housing defining a cavity extending from the first end to the second end; an output shaft arranged coaxially with the axis and extending outwardly from the cavity through the first end; a drive system disposed in the cavity and drivably connected to the output shaft; a gearbox disposed in the cavity and arranged axially between the output shaft and the drive system, the gearbox drivably connected to the drive system and the output shaft; and a rotational controller disposed in the cavity between the drive system and the second end, the rotational controller configured to actuate the drive system to adjust an angular position of the output shaft.

2 . The rotary actuator of claim 1 , wherein the hollow housing is a one-piece housing.

3 . The rotary actuator of claim 2 , further comprising a first seal disposed at the first end and a second seal disposed at the second end, wherein the first and second seals are configured to prevent fluid communication between the cavity and an environment around the hollow housing via the first and second ends.

4 . The rotary actuator of claim 3 , wherein the rotary actuator is configured to operate when submersed in a fluid.

5 . The rotary actuator of claim 1 , wherein the drive system includes:
an electric motor having a rotor shaft; a bearing housing defining a bearing housing cavity extending axially through the bearing housing, the rotor shaft extending partially through the bearing housing cavity; an encoder magnet connected to the rotor shaft and detectable by the rotational controller, the encoder magnet being disposed within the bearing housing cavity; and a shield covering the bearing housing cavity, the shield being disposed between the encoder magnet and the rotational controller.

6 . The rotary actuator of claim 5 , wherein the bearing housing and the shield are configured to prevent fluid communication through the bearing housing cavity.

7 . The rotary actuator of claim 1 , wherein the gearbox is a strain wave gearbox.

8 . The rotary actuator of claim 1 , wherein the rotational controller is covered with a potting compound.

9 . The rotary actuator of claim 8 , wherein the potting compound fills the cavity around the rotational controller.

10 . The rotary actuator of claim 1 , further comprising an idler shaft arranged coaxially with the axis, the idler shaft extending outwardly from the cavity through the second end, and the rotational controller is disposed between the drive system and the idler shaft.

11 . The rotary actuator of claim 10 , wherein the rotational controller includes a first sensor configured to detect an angular position of a rotor shaft of an electric motor and a second sensor configured to detect an angular position of the idler shaft, the first and second sensors being axially spaced from each other.

12 . The rotary actuator of claim 11 , wherein the first sensor and the second sensor are disposed within the cavity.

13 . The rotary actuator of claim 12 , wherein the first and second sensors are arranged coaxially with the axis.

14 . The rotary actuator of claim 1 , wherein the drive system and the gearbox are arranged coaxially with the axis.

15 . A rotary actuator configured to be submersed in a fluid, the rotary actuator comprising:
a one-piece hollow housing extending along an axis, the one-piece hollow housing having: a first sealed end and a second sealed end; a longitudinal cavity extending from the first sealed end to the second sealed end; a plurality of axial segments defining a plurality of inner diameters of the longitudinal cavity; an output shaft arranged coaxially with the axis and extending outwardly from the longitudinal cavity through the first sealed end; a drive system disposed within the longitudinal cavity and drivably connected to the output shaft; a gearbox disposed within the longitudinal cavity and arranged axially between the output shaft and the drive system; and a rotational controller disposed in the longitudinal cavity between the drive system and the second sealed end, the rotational controller configured to actuate the drive system to adjust an angular position of the output shaft.

16 . The rotary actuator of claim 15 , wherein the rotational controller is arranged within a first one of the plurality of axial segments defining a first inner diameter, and
a second one of the plurality of axial segments directly adjacent to the first one of the plurality of axial segments defines a second inner diameter; and a third one of the plurality of axial segments directly adjacent to the first one of the plurality of axial segments defines a third inner diameter; and the second and third inner diameters are smaller than the first inner diameter.

17 . The rotary actuator of claim 16 , further comprising an idler shaft arranged coaxially with the axis, the idler shaft extending outwardly from the longitudinal cavity through the second sealed end, and the rotational controller is arranged between the drive system and the idler shaft.

18 . The rotary actuator of claim 17 , further comprising:
an opening in the one-piece hollow housing axially arranged between the first and second sealed ends of the one-piece hollow housing; and an electrical cable configured to extend through the opening and connect with the rotational controller.

19 . The rotary actuator of claim 17 , wherein:
the drive system includes an electric motor; the rotational controller includes:
a first rotary position sensor configured to detect an angular position of a rotor shaft of the electric motor; and
a second rotary position sensor configured to detect an angular position of the idler shaft.

20 . The rotary actuator of claim 19 , wherein the gearbox is a strain wave gearbox.

Assignees

• Schaeffler Technologies Ag

Inventors

• Hooker Craig
• Derry Brad
• Bartell Peter
• Bailey Josiah
• Briggs Bartholomew

Classifications

• H02G15/046

  with bores or protruding portions allowing passage of cable conductors · CPC title

• H02G15/013

  Sealing means for cable inlets (inlets for cables filled with, or surrounded by, gas or oil H02G15/32) · CPC title

• H02G3/0675

  with bolts operating in a direction parallel to the conductors · CPC title

• G01D5/245

  using a variable number of pulses in a train · CPC title

• F16H2057/02082

  for application in vehicles other than propelling, e.g. adjustment of parts · CPC title