JPH0813184B2 - Linear motor - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor in which a plurality of flat coils can be moved between permanent magnets arranged so as to have a constant magnetic gap.

2. Description of the Related Art Conventionally, two flat coils are provided between permanent magnets arranged so as to have a constant magnetic gap, and the flat coils can be moved by sequentially applying an electric current to the two flat coils. There is a linear motor (Japanese Patent Publication No. 58-4910)
0). In this case, one flat coil is formed by winding a coil around a winding frame, and two flat coils are used as a movable coil assembly.

Problems to be Solved by the Invention When two flat coils are overlapped to form a movable coil as in a conventional linear motor, a magnetic gap between a pair of permanent magnets must be increased, which results in a large device. Will turn into. Further, since the width between the pair of permanent magnets becomes large, there is a problem that a large moving force cannot be generated in the moving coil unless a permanent magnet having a large magnetic force is used. In particular, when trying to form a moving coil from three or more flat coils, the above matters become more and more problematic.

Therefore, in the present invention, the magnetic gap is made small, and
The object is to increase the number of coil turns per unit magnet so that a large moving force can be obtained.

Means for Solving the Problems According to the present invention which has achieved the above object, a pair of permanent magnets having a constant magnetic gap are sequentially arranged in a row on a yoke so as to have opposite poles and opposite poles face each other. A magnetic gap path is formed, a plurality of flat coils having a size that spans two permanent magnets are provided in the magnetic gap path, and the flat coil can be moved along the magnetic gap path by sequentially applying current to each flat coil. In the linear motor, the first, second, and third flat coils having a hollow portion and having a coil width of 1/3 of the width of a permanent magnet are substantially one flat coil. It is characterized in that they are sequentially displaced along the magnetic gap path by the width, and that each flat coil is provided on one synthetic resin plate so as to be on the same plane in the magnetic gap path.

The linear motor of the present invention will be described with reference to FIGS.

A magnetic gap path 3 is formed by arranging a pair of permanent magnets 2a and 2b in a line so as to sequentially have opposite poles with a constant magnetic gap 1 provided, and a movable coil 6 is provided in this magnetic gap path.

The movable coil 6 is provided with flat coils on both surfaces of a synthetic resin plate 10, and a plurality of sets of continuous flat coils 6a, 6b, 6c are provided. The flat coils of each set are arranged along the magnetic air gap path 3 while being sequentially shifted by the coil width of the flat coils. The flat coils 6a, 6b, and 6c of each set are arranged on the same plane in the magnetic air gap path 3 although the portions of the flattened coils 6a, 6b, and 6c that are outside the magnetic air gap path 3 overlap with each other. Form a small gap between the permanent magnets. Flat coil of each set
6a, 6b and 6c are sized to extend over the two permanent magnets 2a and 2b, and a current is sequentially applied to the flat coils of each set.

Action The action of the linear motor of the above means will be described with reference to FIGS.

First, when the flat coils 6a and 6b are applied with currents in opposite directions to each other, a force acts on the flat coils 6a and 6b in the direction of arrow A in FIG.
When it moves to the center of the second permanent magnet 2b, its position is detected, and the flat coil
Switching to current application to 6b and 6c. The flat coil 6b,
The direction of the current in 6c is the opposite direction as in 6a and 6b.

By this switching, a force acts on the flat coils 6a and 6b in the direction of arrow A in FIG. 8B, and the movable coil 6 moves to the state of FIG. 8C. After that, the movable coil 6 can be moved by sequentially switching between the flat coils 6a and 6b and the flat coils 6b and 6c of the movable coil and repeatedly applying a current.

Embodiment An embodiment of the linear motor of the present invention will be described with reference to FIGS.

A pair of permanent magnets 2a, 2b with a constant magnetic gap 1
The magnetic air gap paths 3 are formed by arranging in a row so that the opposite poles are sequentially opposite and the opposite poles face each other. Each permanent magnet 2
a and 2b have a fixed size, are attached to the upper yoke 4 and the center yoke 5, and the movable coil 6 is movably provided in the magnetic gap path 3.

If one movable coil 6 is provided in one magnetic air gap path 3, the movable coil can be moved. However, in this embodiment, since the movable coil 6 is moved in two places, the center yoke 5 and the lower yoke 5 are moved. Another pair of permanent magnets 2a and 2b are sequentially arranged between the pair of permanent magnets 7 and 7 so as to have opposite polarities to the side of the upper yoke, and a magnetic gap path 3 between these pair of permanent magnets is formed.
The movable coil 6 is arranged in the. Side yokes 8 are provided at the ends of the upper yoke 4, the center yoke 5, and the lower yoke 7 to form a magnetic circuit. The upper and lower movable coils 6 are guided by a device (not shown) for movement in the magnetic air gap path 3, and an object to be moved is attached to a portion of each permanent magnet projecting outward from the magnetic air gap 1.

The moving coil 6 is made of glass epoxy or the like shown in FIG.
A set of three flat coils 6a, 6b, 6c is provided on a single synthetic resin plate 10. One set of flat coils is formed by connecting flat coils provided on both sides of a synthetic resin plate 10 to each other. The size of the flat coil in the direction of the magnetic air gap 3 is the same as that of the permanent magnets 2a and 2b. The size is straddled. The three sets of flat coils 6a, 6b, 6c are sequentially arranged along the magnetic gap path 3 by substantially the coil width of one flat coil. The three sets of flat coils are overlapped with each other in a portion projecting outward from the magnetic air gap passage 3, but in the magnetic air gap passage 3 are arranged so that the coil portion enters the central hollow portion of the flat coil and is located on the same plane. (Figs. 2, 5, 6, 7).

The flat coils 6a, 6b, 6c are connected to the power source side so that currents sequentially flow in the opposite directions following the magnetic pole polarities in the magnetic gap 1 which are sequentially reversed. In the case of this embodiment,
The current application to the flat coils 6a and 6b and the current application to the flat coils 6b and 6c are sequentially switched. It should be noted that the switching of the current application to each flat coil is carried out when the flat coils 6a, 6b, 6c are sequentially located at the center of each permanent magnet 2a, 2b, and a known magnetic detection element or optical position not shown The detection is performed using the detection element, and is performed based on the detection signal.

In the movable coil 6 of the above embodiment, three flat coils are provided on the synthetic resin plate 10 by sequentially shifting the flat coils by the coil width, but the number is not limited to three, and a plurality of flat coils may be provided on only one side of the synthetic resin plate. It may be provided.

EFFECTS OF THE INVENTION In the linear motor of the present invention, since a plurality of sets of flat coils forming the movable coil are arranged along the magnetic gap path by being displaced by the coil width, the number of coil turns per unit magnet length is increased and the movable coil is movable. A large moving force can be generated in the coil. Further, since the flat coils of the moving coil are arranged on the same plane in the magnetic air gap path, the magnetic air gap can be kept small, the moving coil can be efficiently generated with a large moving force, and the device becomes large. Nor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial front sectional view of a linear motor of the present invention, FIG. 2 is a plan view of a movable coil portion of the linear motor, FIG. 3 is a side sectional view of the linear motor, and FIG. The drawing shows a movable coil, which is a sectional view taken along the line AA of FIG. 2, and FIG.
6 is a sectional view taken along the line CC of FIG. 2, FIG. 7 is a sectional view taken along the line DD of FIG. 2, and FIG.
FIGS. A, B, and C are explanatory views showing the operation of the linear motor. 1; Magnetic air gap, 2a, 2b; Permanent magnet 3; Magnetic air gap path, 6; Moving coil 6a, 6b, 6c; Flat coil 10; Synthetic resin plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-61-15556 (JP, A) JP-A-59-122359 (JP, A) JP-A-60-11653 (JP, A) Actual development Sho-57- 189285 (JP, U) Actual development Sho 59-179481 (JP, U)

Claims (1)

[Claims] 1. A pair of permanent magnets having a constant magnetic gap are sequentially arranged in a row on a yoke so that opposite poles are opposite to each other and opposite poles face each other to form a magnetic gap path.
A linear motor that has a plurality of flat coils sized to span one permanent magnet and that can move the flat coils along the magnetic gap path by sequentially applying current to each flat coil. And 1 / the width of the permanent magnet
The first, second, and third flat coils having a coil width of 3 are sequentially displaced along the magnetic gap path by substantially the coil width of one flat coil, and each flat coil has a magnetic gap path. A linear motor, which is provided on a single synthetic resin plate so as to be on the same plane inside.