Cable actuator allowing increased joint clearance

Patent metadata

Field	Value
Publication number	US-10035260-B2
Application number	US-201414777922-A
Country	US
Kind code	B2
Filing date	Mar 28, 2014
Priority date	Apr 5, 2013
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A cable actuator comprising a chassis ( 1 ), a screw ( 2 ) rotatably mounted on the chassis and driven by an electric motor, a nut ( 4 ) that engages with the screw and is combined with anti-rotation means such that rotation of the screw under the action of the motor causes an axial displacement of the nut, two cables ( 10 ) coupled to the nut on either side of same, the two cables being wound onto respective joint pulleys ( 11 ) each rigidly connected to a same joint shaft ( 12 ) and in which the joint pulleys have a helical groove, the helical grooves of the pulleys extending in opposing directions.

First claim

The invention claimed is:

1. A cable actuator including:
a chassis;
a screw rotatably mounted on the chassis and driven by an electric motor;
a nut that engages with the screw and is combined with anti-rotation means such that rotation of the screw under the action of the motor causes an axial movement of the nut;
two distinct cables extending symmetrically with respect to a rotation axis of the screw and coupled to the nut on either side thereof;
wherein the two cables are wound onto respective joint pulleys both rigidly connected to the same joint shaft so that the respective cables both wind on their respective pulleys for a first direction of rotation of the same joint shaft, and in which the joint pulleys are of the type that has a helical groove, the helical grooves of the pulleys extending in opposite directions;
wherein the respective joint pulleys have a constant diameter.

2. The cable actuator as claimed in claim 1 , further including idler pulleys with helical grooves rigidly connected to a same idler shaft, the cables being wound onto a respective joint pulley and a respective idler pulley, the helical grooves of the idler pulleys extending in opposite directions.

3. The cable actuator as claimed in claim 2 , wherein the same joint shaft and an idler shaft are interconnected by connecting means imposing proportionality between the rotation speeds of the two shafts.

4. A cable actuator including:
a chassis;
a screw rotatably mounted on the chassis and driven by an electric motor; a nut that engages with the screw, the nut locked against rotation such that rotation of the screw under the action of the motor causes an axial movement of the nut;
a first cable and a distinct second cable, the first cable extending on one side of a rotation axis of the screw and coupled to the nut on one side of the nut;
a second cable, distinct from the first cable, the second cable extending on another side of the rotation axis of the screw and coupled to the nut on a second side of the nut; a first pulley around which a portion of the first cable is wound; a second pulley around which a portion of the second cable is wound; the first pulley and the second pulley are rigidly coupled to rotate together about a common pulley rotational axis, so that rotation of the first pulley and the second pulley cause the first cable and the second cable to wind in a same direction;
the first pulley comprises a first helical groove about the common pulley rotational axis and the second pulley comprises a second helical groove about the common pulley rotational axis, the first helical groove extending in a direction at an angle with respect to the common pulley rotational axis that differs from that of the second helical groove;
wherein the first and second pulleys each have a constant diameter.

5. The cable actuator as claimed in claim 4 , further comprising:
a first idler pulley operatively coupled to the first pulley;
a second idler pulley operatively coupled to the second pulley;
the first idler pulley and the second idler pulley rigidly coupled to rotate together about a common idler pulley rotational axis;
the first idler pulley comprises a first idler helical groove about the common idler pulley rotational axis and the second idler pulley comprises a second idler helical groove about the common idler pulley rotational axis, the first idler helical groove extending in a direction at an angle with respect to the common idler pulley rotational axis that differs from that of the second idler helical groove.

6. The cable actuator as claimed in claim 5 , wherein the first idler pulley is operatively coupled to the first pulley by the first cable and the second idler pulley is operatively coupled to the second pulley by the second cable.

7. The cable actuator as claimed in claim 5 , wherein the first pulley and the second pulley are rigidly coupled to rotate together by a pulley joint shaft and the first idler pulley and the second idler pulley are rigidly coupled to rotate together by an idler pulley joint shaft; and wherein the pulley joint shaft and the idler joint shaft are operatively connected by a toothed belt or chain imposing proportionality between rotation speeds of the pulley joint shaft and the idler joint shaft.

Assignees

• Commissariat Energie Atomique

Inventors

• Kfoury Fares
• Garrec Philippe

Classifications

• F16H2019/0695

  Generating pivoting movement of a joint · CPC title

• F16H2025/2075

  Coaxial drive motors · CPC title

• F16H19/0622

  for converting reciprocating movement into oscillating movement and vice versa, the reciprocating movement is perpendicular to the axis of oscillation · CPC title

• F16H25/20

  Screw mechanisms (with automatic reversal F16H25/12) · CPC title

• F16H2025/204

  Axial sliding means, i.e. for rotary support and axial guiding of nut or screw shaft · CPC title