Electric actuator
AssigneeSMC Corporation
InventorsToshio Sato, Shogo Miyazaki, Akira Tadano
Life of this patent
Estimating the term…
Abstract
A nut member 5 for moving forward and rearward by rotating a feed screw 4 by a stepping motor 28 and a transfer table 7 for transferring a workpiece W are elastically connected by a spring means 24 in transferring of the workpiece to thereby allow the nut member 5 to overrun by flection of the spring means 24, to allow the stepping motor 28 to rotate excessively in a cushioned manner, and to obtain a thrust for pushing the workpiece against an object after the transfer table 7 reaches the transfer end of the workpiece.
Claims11
An electric actuator comprising a feed screw in a shape of a straight rod rotatably supported by a bearing member on a base,
- a nut member screwed to said feed screw to reciprocate in an axial direction of said feed screw by normal and reverse rotation of said feed screw,
- a transfer table connected to said nut member with a degree of freedom in said axial direction of said feed screw to transfer a workpiece by moving to follow said nut member,
- a stepping motor a rotation amount of which can be controlled according to the number of drive pulses,
- a transmission mechanism for transmitting rotating force of said stepping motor to said feed screw, and
- spring means disposed between said nut member and said transfer table to elastically connect said transfer table and said nut member when said transfer table transfers said workpiece to thereby allow said nut member to overrun, to allow said stepping motor to excessively rotate in a cushioned manner, and to apply a necessary thrust to said transfer table after said transfer table reaches a transfer end of said workpiece.
Dependencies are inferred from the claim text.