US 8,384,317 B2 · Linear motor device

Abstract

Provided is a linear motor device which is compact even when a stroke is increased, which can reduce heat generation, and which can eliminate damping force caused by circulating current. The linear motor device includes a linear motor that includes a movable member having a plurality of fields and a stator in which a plurality of armatures including polyphase coils are arranged in line in the moving direction of the movable member, and a controller that sequentially outputs control commands to current amplifiers respectively connected to the armatures in accordance with the relative position of the movable member. The controller selectively outputs the control commands to only the current amplifiers corresponding to the armatures which are opposite the movable member such that the armatures are positioned within a range corresponding to the length in the moving direction of the movable member.

Claims9

Dependent claims

A linear motor device comprising:

a linear motor that includes a movable member having a plurality of fields and a stator in which a plurality of armatures having polyphase coils are arranged in line in the moving direction of the movable member;
a position detector that detects the relative position of the movable member;
a plurality of current amplifiers connected to the armatures, respectively, each current amplifier supplying current based on a control command to excite the corresponding armature;
and
a controller that sequentially outputs the control commands to the current amplifiers in accordance with the relative position of the movable member, the controller selectively outputting the control commands to only the current amplifiers corresponding to the armatures which are opposite the movable member such that the armatures are positioned within a range corresponding to the length in the moving direction of the movable member.

2 more elements

A linear motor device comprising:

a linear motor that includes a movable member having a plurality of fields and a stator in which a plurality of armatures having polyphase coils are arranged in a predetermined number of parallel lines in the moving direction of the movable member, the parallel lines being shifted by a predetermined shift amount;
a position detector that detects the relative position of the movable member;
a plurality of current amplifiers connected to the armatures, respectively, each current amplifier supplying current based on a control command to excite the corresponding armature;
and
a controller that sequentially outputs the control commands to the current amplifiers in accordance with the relative position of the movable member, the controller selectively outputting the control commands to only the current amplifiers corresponding to the armatures which are opposite the movable member such that the armatures are positioned within a range corresponding to the length in the moving direction of the movable member.

2 more elements

Dependencies are inferred from the claim text.

Linear motor device

Life of this patent

Linear motor device

Life of this patent

Abstract

Claims9