JPS6328203A - Position detector - Google Patents

Abstract

PURPOSE:To detect the position of propulsion or levitation winding without providing a special unit by detecting any of the positions of the propulsion and levitation windings from a signal of a predetermined frequency of a voltage induced in a field pole. CONSTITUTION:The propulsion force of a vehicle 2 is obtained by a propulsion winding 1 and a field pole 3, and a levitation force is obtained by a repulsion with a reaction magnetic flux due to a current induced in the levitation winding, not shown, by the magnetic flux of the pole 3 and the pole 3. When an AC flows in the winding 1 to drive the vehicle 1, an induced voltage is generated in the pole 3 disposed oppositely to the winding. A voltage across the predetermined pole 3 is applied to an amplifier 6 and a filter 7 to produce a signal of necessary frequency, and the signal is supplied to a position detector 8 to detect the position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a position detection device for a linear motor, and more particularly to a position detection device capable of detecting a position using field poles of a linear motor.

[Conventional technology]

A conventional position detection device of this type, as shown in FIG.
A levitation winding (not shown) for levitation and a propulsion winding 1 for propulsion are provided on the orbit, a field pole 3 of a superconducting magnet is provided on the vehicle 2, and a power converter is attached to the propulsion winding 1. In a linear motor that generates propulsion force by generating a moving magnetic field by sequentially passing current from (not shown), detection plates 4 are provided on the track at predetermined intervals, and these are installed on the vehicle 2 for optical position detection. The device 5 was used to detect the position. Incidentally, a device similar to this position detection device is disclosed in Japanese Patent Application Laid-open No. 189170/1983.

There is one described in JP-A-56-182389.

[Problem that the invention seeks to solve]

However, according to the above-mentioned position detection device, there is a problem in that in addition to disposing the detection plates 4 on the ground track at predetermined intervals, a special device such as the optical position detection device 5 must also be provided on the vehicle 1. There was a point.

An object of the present invention is to provide a position detection device that can detect a position with a simple configuration without providing a special device for detecting the position.

[Means for solving problems]

The position detection device of the present invention, which solves the above problems, uses a linear motor that is propelled by providing a propulsion winding and a levitation winding on a track, a field pole on a vehicle, and sequentially passing current through the propulsion windings. In the position detection device, the voltage induced in the field pole is captured.

The vehicle is provided with means that can detect the position of either the propulsion or levitation windings from a signal of a predetermined frequency of this voltage.

[Effect]

A constant current flows through the field winding, and a constant voltage is applied to its terminals. However, since the height varies depending on the propulsion coil as it is propelled or levitated, the position can be detected by detecting this.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. Third
Components that are the same as those in the figures are given the same reference numerals.

FIG. 1 is a block diagram showing an embodiment of the present invention. A superconducting magnet is used for the field pole 3 provided in the vehicle 1-H, and a constant persistent current flows through the air-core coil. The propulsion force of the vehicle 2 is obtained by the propulsion winding 1 and the field pole 3, and the levitation blade is generated by the levitation winding (
(not shown) is obtained by repulsion with a reaction magnetic flux caused by an induced current. Although a direct current is constantly flowing through the field pole 3, since the current is constant, the voltage across the field pole 30 does not change and remains constant. When an alternating current is applied to the propulsion winding 1 in order to propel the vehicle 2, an induced voltage is generated in the field pole 3 located opposite to the propulsion winding 1. It was found that the induced voltage is proportional to the flow of the propulsion winding 10, and that the induced voltage repeats small and small depending on the relative position to the propulsion winding 1. Using this, the position of each propulsion winding 1 can be determined. You'll understand. Similarly, the reaction magnetic flux due to the levitation winding increases in proportion to the speed of the traveling vehicle, but it was found that the induced voltage repeatedly changes from small to small for each levitation winding. You will know the position of each line. It has also been found that the voltage induced across the field pole 3 is small at low speeds and low currents.

Therefore, a predetermined voltage across the field pole 3 is applied to the amplifier 6,
Amplifier 6 amplifies the signal. The signal amplified by the amplifier 6 passes through the filter 7 to generate only the necessary frequency signal, and this signal is supplied to the position ejection part 8 and the field pole 3
The voltage induced in the pigeon is used to detect the position of the pigeon.

FIG. 3 is a block diagram showing an embodiment of a song according to the present invention.

The difference between the other embodiments and the embodiment shown in FIG.
, 7B are provided in separate systems, and each filter 7A,
7B is located at the point KL& to supply the output signal to the position detecting section 8. That is, the field poles 3A, 3B are selected to be front and rear of the vehicle, or left and right in the same phase, so that even if one of the field poles 3A, 3B fails, it can be detected. The 6 amplifiers, 6B, and the 7 filters, 7B may all have the same specifications,
It may be the same as when there is one field pole as in the previous embodiment. The position detection unit 8Fi may be switched to the normal state due to a failure of the field pole 3, or the detection signal may be used in a harmonic manner for detection.

〔Effect of the invention〕

As described above, according to the present invention, since field poles are used, it is not necessary to provide any special equipment on the track, and there is also an advantage that no special equipment is required on the vehicle.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing another embodiment of the invention, and FIG. 3 is an explanatory diagram showing a conventional example. 3... Field pole, 6... Amplifier, 7... Filter, 8... Position detection section.

Claims (1)

[Claims] 1. In a position detection device for a linear motor that is propelled by providing a propulsion winding and a levitation winding on a track, a field pole on a vehicle, and sequentially passing current through the propulsion winding, What is claimed is: 1. A position detection device comprising a vehicle equipped with means capable of capturing a voltage at a predetermined frequency and detecting the position of either a propulsion winding or a levitation winding from a signal at a predetermined frequency of the voltage.