JP2008064537A - Linear resolver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make position sensing of high precision regardless of deflection of the mover by making the long mover freely movable in the space of each separately arranged magnetic stator. <P>SOLUTION: The linear resolver of this invention is constituted such that on the long base (1), in each space (15) of each stator of magnetic substance (2), the long mover (20) is made freely movable. Depending on a variation of the interlinked area between the stator pieces (11 and 12) and the curved surface (21) of the mover (20), the induced voltage is generated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a linear resolver, and in particular, the longitudinal mover is movable in the gaps of a plurality of magnetic stators arranged in a divided manner, and the area interlinked with each stator piece of the magnetic stator changes, The present invention relates to a novel improvement for generating an induced voltage in a detection winding and performing highly accurate position detection irrespective of the movement of the mover.

Conventionally, this type of linear resolver includes a linear resolver disclosed in Patent Document 1.
That is, in the linear resolver disclosed in Patent Document 1, a movable element having a movable winding having a concavo-convex shape is movable relative to a concavo-convex shaped stator, and is movable as the movable element moves. The linear resolver signal is obtained from the detection winding of the winding.

JP-A-6-300583

Since the conventional linear resolver is configured as described above, the following problems exist.
In other words, since the movable element having a concave and convex movable winding is linearly moved at a predetermined interval with respect to the concave and convex stator, the stator and the movable element are exactly aligned in plan view. Therefore, when the mover is shaken, the detection accuracy is adversely affected.
Further, since the stator has an integral structure, the magnetic field distribution affects other magnetic poles, and it is difficult to improve detection accuracy.

  The linear resolver according to the present invention includes n pairs of magnetic stators arranged periodically or aperiodically on a longitudinal base, and a stator core for making each of the magnetic stators U-shaped. Between a pair of stator pieces provided on both sides via a gap, an excitation winding and a detection winding provided around the stator core, and each stator piece of each magnetic stator A longitudinal mover that is provided so as to be reciprocally movable in a linear direction within the gap, and a change surface that is formed on a surface of the longitudinal mover facing the stator core and changes in a wave shape. The structure is such that the area interlinked with each stator piece is changed by movement, and the change surface is formed in a sine shape or a cycloid shape, and each magnetic body is fixed. The child consists of a Cos phase stator and a Sin phase stator. Pitch of Cos phase stator and Sin phase stator is lambda / 4, the pitch between between the Cos phase stator and the Sin phase stator is a configuration in which a lambda / 2.

Since the linear resolver according to the present invention is configured as described above, the following effects can be obtained.
That is, since each magnetic stator is divided and arranged, there is no distortion of the excitation magnetic field distribution, and highly accurate position detection can be performed.
Further, since a gap is formed by a pair of stator pieces provided on both sides of the stator core, and the longitudinal mover is movable in the gap, the movement displacement of the mover is caused by the chain between each stator and the mover. Depending on the amount of crossing, stable detection accuracy can be obtained regardless of the movement of the mover.
In addition, since the longitudinal mover is movably disposed in the gap of each stator piece of the magnetic stator, the total height of the linear resolver itself can be kept lower than before, and the flat type and can do.

  The present invention makes it possible to move the longitudinal mover into the gaps of a plurality of magnetic stators arranged in a divided manner, and the area interlinked with each stator piece of the magnetic stator changes, and an induced voltage is applied to the detection winding. It is an object of the present invention to provide a linear resolver that generates high-precision position detection regardless of the movement of the mover.

DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a linear resolver according to the present invention will be described with reference to the drawings.
In FIG. 1, what is indicated by reference numeral 1 is a longitudinal base of a longitudinal shape made of a non-magnetic material, and in the longitudinal direction on the longitudinal base 1, a plurality of periodic and aperiodically divided arrangements are provided. A magnetic stator 2 is arranged.

Although only four magnetic stators 2 are shown in FIG. 1, the number of magnetic stators 2 may be any number depending on the detection specifications, and the phases are different from each other (that is, the pitches are different from each other by λ / 4). ) Cos phase stator 2A and Sin phase stator 2B.
The pair of Cos phase stators 2A are arranged with a pitch of λ / 2 from each other, and the pair of Sin phase stators 2B are arranged with a pitch of λ / 2 from each other. The phase stator 2A and each Sin phase stator 2B are not limited to the configuration shown in FIG.

Each of the magnetic material stators 2 is configured as shown in FIGS.
In other words, a pair of plate-shaped stator pieces 11 and 12 are attached to both sides of a square-plate-shaped stator magnetic core 10, and the overall shape is formed by the stator magnetic core 10 and each of the stator pieces 11 and 12. Is formed in a U-shape or a U-shape.

  As shown in FIG. 3, an excitation winding 13 and a detection winding 14 are wound around the stator core 10, and the stator core 10, the stator pieces 11 and 12, and the excitation winding are provided. The magnetic stator 2 is constituted by the wire 13 and the detection winding 14.

  In a gap 15 formed between the stator pieces 11 and 12 of each magnetic stator 2, a longitudinal movable element 20 made of a magnetic material and having a longitudinal shape is reciprocally movable along the direction of arrow A. The longitudinal movable element 20 is provided and connected to a reciprocating member (not shown) so as to reciprocate.

  The lower surface of the longitudinal mover 20, that is, the surface facing the stator core 10 around which the windings 13 and 14 are wound when combined with the magnetic stator 2 is wavy, that is, a sine shape. Or the change surface 21 formed in the cycloid shape is continuously formed along the longitudinal direction.

  Therefore, when the longitudinal movable element 20 reciprocates in the direction of the arrow A in each gap 15, the area that is linked to the stator pieces 11 and 12 is changed along the change surface 21 by the change surface 21. It is configured as follows.

  Next, in the above-described configuration, when an excitation signal composed of an AC voltage having a predetermined frequency is applied to the excitation winding 13, each magnetic stator 2 is divided on the longitudinal base 1 and independently arranged at predetermined intervals. Therefore, the magnetic field distribution generated from each excitation winding 13 is stably generated without being affected by the longitudinal movable element 20 or the like.

When the longitudinal movable element 20 is reciprocated in each gap 15 in the above-described state, the amount of linkage of the gap 15 changes depending on the shape of the change surface 21, that is, the area linked with the pair of stators 11 and 12. Changes, and the induced voltage generated in each detection winding 14 outputs a two-phase signal of Sin and Cos as a resolver signal of a linear resolver accompanying the movement of the longitudinal movable element 20.
This two-phase signal is digitized through a well-known R / D converter and used for controlling a digital device.

Therefore, in the conventional linear resolver, when the moving shaft of the mover is swung, the gap changes and an accuracy error occurs. However, in the present invention, the gap 15 is fixed between the stators 11 and 12, so that the gap 15 is fixed. , Magnetic accuracy does not decrease and no detection error occurs. Further, the information on the movement displacement of the longitudinal movable element 20 depends on the amount of interlinkage between the pair of stators 11 and 12 and the longitudinal movable element 20, and does not depend on the shake of the longitudinal movable element 20.
In the conventional configuration, the exciting magnetic body is magnetically integrated. In the present invention, each magnetic stator 2 as the exciting magnetic body is electrically integrated, but magnetically, the longitudinal base 1 is integrated. Since it is divided and independent, the magnetic characteristics can be improved.

It is a perspective view which shows the linear resolver by this invention. It is a perspective view which shows the longitudinal needle | mover of FIG. It is an expansion perspective view which shows the magnetic body stator of FIG. It is a perspective view which shows the state which removed the coil | winding of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Longitudinal base 2 Magnetic body stator 2A Cos phase stator 2B Sin phase stator 10 Stator magnetic core 11, 12 Stator piece 13 Excitation winding 14 Detection winding 15 Air gap 20 Longitudinal movable element 21 Change surface

Claims (3)

N pairs of magnetic stators (2) divided periodically or non-periodically on the longitudinal base (1), and each magnetic stator (2) to form a U-shaped stator magnet A pair of stator pieces (11, 12) provided on both sides of the core (10) via a gap (15), and an excitation winding (13) provided by being wound around the stator magnetic core (10) And a longitudinal mover provided so as to be reciprocally movable in a linear direction within a gap (15) between the stator windings (11, 12) of each of the magnetic stator (2) and the detection winding (14) ( 20), and a change surface (21) that is formed in a surface facing the stator core (10) of the longitudinal mover (20) and changes in a wave shape,
A linear resolver characterized in that an area interlinking with each stator piece (11, 12) is changed by the movement of the longitudinal movable element (20).   2. The linear resolver according to claim 1, wherein the change surface (21) is formed in a Sin shape or a cycloid shape.   Each of the magnetic stators (2) includes a Cos phase stator (2A) and a Sin phase stator (2B), and the pitch between the Cos phase stator (2A) and the Sin phase stator (2B) is λ. The linear resolver according to claim 1 or 2, wherein a pitch between said Cos phase stators (2A) and between each Sin phase stator (2B) is λ / 2.

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