Linear actuator
First Claim
1. A linear actuator for driving a driven member, comprising:
- housing;
an electric motor attached to said housing; and
a power transmission mechanism for transmitting motive power of said electric motor to said driven member,said power transmission mechanism including;
a fixing portion;
a rotation driving portion so connected to said electric motor as to be capable of transmitting the motive power;
a rotation driven portion receiving a rotational force from said rotation drive portion and getting rotationally displaced;
a converting mechanism for converting a rotational motion of said rotation driven portion into an axis-line directional motion of a movable member so connected to said driven member as to be capable of transmitting the motive power; and
a lock member disposed between said fixing portion and said rotation driven member,wherein when a rotational force is inputted to said rotation driving portion to rotate said rotation driven portion, said lock member is guided to a first position in which there decreases a frictional force with said fixing portion and said rotation driven portion, the transmission of the rotational force to said rotation driven portion from said rotation driving portion is thereby permitted,when the rotational force is inputted to said rotation driven portion to rotate said rotation driving portion relatively in one direction, said lock member is guided to a second position in which there increases the frictional force with said fixing portion and said rotation driven portion, the rotation to said rotation driving portion from said rotation driven portion is thereby fixed, andsaid rotation driven portion receives a force from said driven member so as to rotate in one direction at least in a state where said driven member is driven.
1 Assignment
0 Petitions
Accused Products
Abstract
A rotary shaft and a rotation driven member are connected as to transmit motive power when the rotary shaft rotates relatively to the rotation driven member. A roller gets displaced to a first position where a frictional force with an outer race and the rotation driven member decreases, thereby permitting transmission of a rotational force from the rotary shaft to the rotation driven member. When the rotation driven member rotates relatively to the rotary shaft, the roller gets displaced to a second position where the frictional force with the outer race and the rotation driven member increases, thereby rotationally fixing the rotation driven member with respect to the outer race. The power transmission from a brake apparatus to an electric motor can be hindered while permitting the power transmission to the brake apparatus from the electric motor by using either a worm exhibiting a relatively low transmission efficiency or a worm wheel.
35 Citations
25 Claims
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1. A linear actuator for driving a driven member, comprising:
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housing; an electric motor attached to said housing; and a power transmission mechanism for transmitting motive power of said electric motor to said driven member, said power transmission mechanism including; a fixing portion; a rotation driving portion so connected to said electric motor as to be capable of transmitting the motive power; a rotation driven portion receiving a rotational force from said rotation drive portion and getting rotationally displaced; a converting mechanism for converting a rotational motion of said rotation driven portion into an axis-line directional motion of a movable member so connected to said driven member as to be capable of transmitting the motive power; and a lock member disposed between said fixing portion and said rotation driven member, wherein when a rotational force is inputted to said rotation driving portion to rotate said rotation driven portion, said lock member is guided to a first position in which there decreases a frictional force with said fixing portion and said rotation driven portion, the transmission of the rotational force to said rotation driven portion from said rotation driving portion is thereby permitted, when the rotational force is inputted to said rotation driven portion to rotate said rotation driving portion relatively in one direction, said lock member is guided to a second position in which there increases the frictional force with said fixing portion and said rotation driven portion, the rotation to said rotation driving portion from said rotation driven portion is thereby fixed, and said rotation driven portion receives a force from said driven member so as to rotate in one direction at least in a state where said driven member is driven. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
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Specification