JPS6134605B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnet generating body that generates magnetic fields in directions that intersect with each other on a two-dimensional plane. The present invention provides a magnet generating body that is optimal as a magnetic scale, etc. when detecting a position on a dimensional plane.

Conventionally, linear magnetic scales and magnetoelectric transducers, in which magnetized regions that generate signal magnetic fields in different directions are arranged sequentially in one direction to form a one-dimensional magnetic lattice, have been used to measure one-dimensional length and displacement. By arranging the linear magnetic scales perpendicular to each other, each displacement on the horizontal and vertical axes can be individually detected from each magnetic scale to perform two-dimensional measurement. was going there. However, a two-dimensional scale device configured using two linear magnetic scales requires a mechanism that decomposes the two-dimensional displacement into the displacement on the vertical axis and the displacement on the horizontal axis. Therefore, the configuration becomes complicated. In addition, a magnetic body is disposed movably in two dimensions on a plane in which a large number of detection wires are two-dimensionally orthogonally arranged, and a detection signal that is electromagnetically induced in the detection wire by the magnetic field from the magnetization body is generated. An electromagnetic induction type two-dimensional scale device has also been proposed that measures the amount of displacement of the magnet, but this scale device requires complicated wiring for detection wires and a complicated external circuit. Requires.

Therefore, in view of the problems in the conventional scale device as described above, the present invention provides a first
a first magnetic field region in which a magnetized belt and a second magnetized belt magnetized to the south pole are arranged alternately parallel to the horizontal axis direction on a two-dimensional plane; A second magnetic field region in which magnetic bands and second magnetized bands are arranged alternately in parallel to the vertical axis direction on the two-dimensional plane and alternately arranged in the vertical axis direction on the two-dimensional plane. To provide a magnetic generating body that can realize a magnetic scale forming a two-dimensional magnetic lattice for detecting, for example, two-dimensional displacement or position. It is.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a magnetic generating body according to the present invention is applied to a magnetic scale device will be described in detail below with reference to the drawings.

In the embodiment shown in FIG.
1 are signal magnetic fields Hsx, Hsy in mutually orthogonal directions
The first magnetic field region 11 and the second magnetic field region 13 that generate the magnetic field are arranged alternately in the vertical axis direction and the horizontal axis direction on a two-dimensional plane. Each of the above magnetic field regions 1
2 and 13 are first magnetized belts 14 magnetized to N poles;
and a second magnetized belt 15 magnetized to the S pole, and are formed by alternately arranging _λ
A magnetic lattice is formed that generates signal magnetic fields H _SX , H _SY of λ _Y . Each of the above magnetic field regions 12,1
3, the length Xn of one side in the horizontal axis direction and the length Yn of one side in the vertical axis direction are set to be equal to each other.

Then, in order to detect the signal magnetic field H _SY from the magnetic grating of the magnetic scale 11, a pair of magnetoelectric transducers 16 and 17 are arranged to be movable relative to the magnetic scale 11 in the horizontal direction. There is.

Each of the above-mentioned magnetoelectric transducers 16 and 17 is made of NiCo alloy, NiFe alloy, NiAl alloy, NiMn alloy or
It consists of a magnetoresistive element having a flat band-shaped current passage formed of an anisotropic ferromagnetic metal material having a magnetoresistive effect such as NiZn alloy, and detects the signal magnetic field H _SY from the magnetic lattice and detects the phase difference. outputs a two-phase detection output of 90° (m/2+1/
8) Arranged parallel to the horizontal axis at intervals of λ _Y.

In this embodiment, the magnetoelectric transducer 16,
17, as shown in FIG. 2, each signal magnetic field H _SY
The current path portions 18a, 18b are arranged in parallel at an interval of λ _Y /2, and the current path portions 19a, 19 are similarly arranged in parallel at an interval of λ _Y /2.
Each of the current passage portions 18a, 18b, in a broken line pattern, is arranged by shifting (n+1/4)λ _Y from the current passage portion 18a, 18b,
19a and 19b are connected in series. The length Lx in the longitudinal direction of each of the current path portions 18a, 18b, 19a, and 19b is an even multiple (in this embodiment, twice) of the length Xn in the horizontal axis direction of the magnetic field regions 12 and 13 of the magnetic scale 11. is set to . Further, the magnetoelectric transducers 16 and 17 are provided with a bias magnetic field H _B from a bias magnetic field magnet (not shown) in parallel to the direction of the bias current I _B , and a bias current I _B is applied from the constant voltage source 20. Supplied.

Here, the flat band-shaped current path portion formed of a ferromagnetic metal material exhibits a maximum resistance value R when it is parallel to the bias current I _B and the magnetization direction, and a minimum resistance value R when it is perpendicular to the bias current I B and the magnetization direction. The resistance value R(θ) per unit length is a function of the angle θ between the bias current and the magnetization direction R(θ)=R sin ² θ+R cos ² θ...th It can be expressed by the Vioght-Thomson equation of the first equation.

In the embodiment having the above-described configuration, each current path portion 18a, 18b,
19a and 19b have a signal magnetic field H _SY in a direction parallel to the bias current I _B in a half region in the longitudinal direction.
is given, and the other half region is given a bias current I
A signal magnetic field _HSX in a direction perpendicular to _B is always applied. Therefore, for example, as shown in FIG. 1, when the current passage portion 18a is located within a range of length Y ₁ in the vertical axis direction, the magnetic scale 11 and the magnetoelectric conversion element 16 in the horizontal axis direction are Due to the relative movement of
Depending on their relative positions, the resistance value of the half region a of the current path section 18a changes in response to the signal magnetic field Hsy from the magnetic grating of the magnetic scale 11, and the resistance value of the other half region remains constant. Retained. Further, when the magnetic scale 11 and the magnetoelectric transducer 16 move relative to each other in the horizontal axis direction and the current path portion 18a is positioned within the range of length _Y2 , the resistance value of the region a becomes constant and the other half The resistance value in the region changes in response to the signal magnetic field _HSY . Note that even if the magnetic scale 11 and the magnetoelectric transducer 16 move relative to each other in the vertical axis direction, the signal magnetic field H _S parallel to the bias current I _B
The ratio of the region a given by _Y to the region given _by the signal magnetic field _H 11 magnetic field regions 12,
13, the total resistance value of the current path section 18a does not change. In addition, other current path portions 18b, 19a, 1
Similarly to 9b, the resistance value changes periodically according to the signal magnetic field _HSY . Furthermore, other magnetoelectric conversion elements 17
Similarly, the resistance value of each current path section changes periodically in accordance with the signal magnetic field _HSY . Above magnetic scale 1
Since the bias magnetic field H _B is applied in parallel to the bias current I _B , the total resistance value of the current path section due to the relative movement in the horizontal axis direction between the magnetic scale 11 and each magnetoelectric transducer 16 and 17 is as follows. The wavelength of the magnetic lattice λ changes with a repetition period equal to _Y.

Therefore, for the wavelength λ _Y of the signal magnetic field H _SY of the magnetic grating of the magnetic scale 11, (m/2+1/8)λ _Y
Each magnetoelectric transducer 1 arranged with an interval of
Each output terminal 10A, 10B of 6, 17 receives two-phase detection output signals with a phase difference of 90° as the magnetic scale 11 and each magnetoelectric transducer 16, 17 move relative to each other in the vertical axis direction. The signal magnetic field H SY from the magnetic grating of the magnetic scale 11 is obtained at a repetition period equal to 1/1/the wavelength λ _Y of the signal magnetic field H _SY . For each of the two-phase detection output signals with a phase difference of 90°, the wavelength λ _Y can be interpolated to 1/N by using an interpolation processing circuit such as a multiphase circuit (not shown). Highly accurate position detection is possible.

In this example, position detection was performed in the vertical axis direction on the two-dimensional plane, but a magneto-electric transducer having a current path section arranged parallel to the horizontal axis on the two-dimensional plane may be used. It is also possible to detect the position in the horizontal axis direction.

Next, in the embodiment shown in FIG. 3, the magnetized bands 14 and 15 of the magnetic scale 11 in the above embodiment are formed by dot-shaped magnetized portions 25 and 26.

In this embodiment, the magnetic scale 21 is N
A first magnetized section 25 whose pole is magnetized is arranged equivalently to the above-mentioned first magnetized zone 14, and a second magnetized section 26 whose S pole is magnetized is arranged equivalently to the above-mentioned first magnetized zone 14. They are arranged equivalently to the second magnetized belt 15. And the above first
The first magnetic field region 2 and the second magnetic field region 23 formed by the magnetized portion 25 and the second magnetized portion 26 are alternately arranged sequentially in the vertical axis direction and the horizontal axis direction on the two-dimensional plane. Arranged. In the first magnetized region 22, the signal magnetic field _HSX in the horizontal axis direction is obtained between the first magnetized section 25 and the second magnetized section 26. Further, in the second magnetic field region 23, the signal magnetic field _HSY in the vertical axis direction is obtained between the first magnetized section 25 and the second magnetized section 26. That is, a magnetic lattice is formed having signal magnetic fields H _SX and H _SY obtained from the respective magnetic field regions 22 and 23 in mutually orthogonal directions.

In this embodiment, the magnetic scale 2
In order to detect each signal magnetic field H _SX , H _SY from one magnetic grid, N pairs of magnetoelectric transducers 31A, 31
B, 32A, and 32B are arranged to be movable relative to the magnetic scale 21 in the horizontal direction.
Each of the above magnetoelectric conversion elements 31A, 31B, 32A, 3
2B denotes each current passage portion 28 in a broken line pattern formed of a ferromagnetic metal material as in the above embodiment.
a, 28b, 29a, and 29b, respectively, and a bias current I is supplied from a constant voltage source 30 to each current path section 28a, 28b, 29a, and 29b. In addition, each of the current path portions 28a, 28b, 29a,
A bias magnetic field H _B from a bias magnet (not shown) is applied to 29b in a direction of 45° with respect to the direction of the bias current I _B . Furthermore, the two pairs of magnetoelectric conversion elements 31A, 31B, 32A, 3
A pair of magnetoelectric conversion elements 31A and 31B of 2B
In order to detect the signal magnetic field _HSX from the magnetic grid of the magnetic scale 21, each current path section 28
a, 28b, 29a, 29b are located parallel to the horizontal axis direction, and the signal magnetic field H _SX
They are arranged at an interval of (m/2+1/2) _λX with respect to the wavelength _λX . Further, the other pair of magnetoelectric conversion elements 32A and 32B are connected to the magnetic scale 2.
In order to detect the signal magnetic field _HSY from the magnetic grid 1, each current path section 28a, 28b, 29a, 29
b is located parallel to _the horizontal axis direction and (m/2+1/
2) They are arranged with an interval of λ _Y.

In the embodiment configured as described above, when the magnetic scale 21 of each magnetoelectric transducer 31A, 31B, 32A, 32B is moved relative to the magnetic scale 21, each output terminal 31 of one pair of magnetoelectric transducer 31A, 31B
A two-phase detection output signal corresponding to the relative movement amount component in the horizontal axis direction on the two-dimensional plane is obtained from a and 31b,
In addition, the other pair of magnetoelectric conversion elements 32A, 32B
A two-phase detection output signal corresponding to the relative movement amount component in the vertical axis direction on the two-dimensional plane is obtained from each output terminal 32a, 32b. Each of the detection output signals is generated by each signal magnetic field H from the magnetic grating of the magnetic scale 21.
The wavelengths _SX and H _SY change repeatedly with a period of 1/2 of each of the wavelengths λ _X and λ _Y .

As is clear from the description of the above embodiments, the magnetizing body according to the present invention has a first magnetized band magnetized to the north pole and a second magnetized band magnetized to the south pole. The first magnetic field regions are arranged alternately in parallel to the horizontal axis direction on the two-dimensional plane, and the first magnetized zone and the second magnetized zone are arranged in the vertical axis direction on the two-dimensional plane. By arranging the second magnetic field regions alternately and parallel to each other in the vertical axis direction on the two-dimensional plane, it is possible to generate magnetic fields in mutually orthogonal directions on the two-dimensional plane. By using this magnetized body as a magnetic scale, a detection output corresponding to the amount of displacement or position on a two-dimensional plane can be obtained from a magneto-electric conversion element that can move freely relative to the magnetic scale on which a two-dimensional magnetic lattice is formed. A signal can be obtained at a repetition period corresponding to the wavelength of the signal magnetic field from the magnetic grating, and a two-dimensional scale device with an extremely simple configuration can be realized, and the intended purpose can be fully achieved. .

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing the structure of an embodiment in which the magnetizing body according to the present invention is applied to a magnetic scale device, and FIG. 2 is a schematic plan view showing the structure of the magnetoelectric conversion element used in the above embodiment. FIG. Third
The figure is a schematic plan view showing the configuration of another embodiment in which the magnetizing body according to the present invention is applied to a magnetic scale device. 11, 21...Magnetic scale, 12, 13, 2
2, 23... Magnetic field region, 14, 15... Magnetized zone, 2
5, 26... Magnetized part.

Claims (1)

[Claims] 1. A first magnetized band magnetized to the north pole and a second magnetized band magnetized to the south pole are arranged parallel to the horizontal axis direction on a two-dimensional plane and A first magnetic field region arranged alternately, and a second magnetic field region arranged alternately in parallel to the vertical axis direction on a two-dimensional plane. and are arranged alternately in the vertical axis direction on a two-dimensional plane. 2. The magnet as set forth in claim 1, wherein the first magnetized band and the second magnetized band are each formed by arranging dot-shaped magnetized portions in a strip shape. Magnetic material.