Contactless galuano-magnetro effect apparatus

Claim 2

A contactless galvano-magnetro effect apparatus comprised of a. a magneto-resistance effect device having an endless circular shape; b. conductive electrodes which are arranged to cross the surface of the device at at least two positions so that the device is divided into at least two resistance yokes; c. a magnetic field applying means which is positioned opposite to the device so that the flux density of the magnetic field applied to at least one resistance yoke can be varied; and d. connections associated with the electrodes for an external input power supply and load, whereby the resistance value of the resistance yoke can be varied with the variation of the flux density of the magnetic field.

Claim 3

A contactless galvano-magnetro effect apparatus according to claim 1, wherein at least one conductive segment, which crosses the surface of at least one resistance yoke, is provided.

Claim 4

A contactless galvano-magnetro effect apparatus according to claim 2, wherein a plurality of conductive segments are arranged on thE resistance yoke so that the distances between adjacent conductive segments are successively decreased from one electrode in the direction of the other electrode.

Claim 5

A contactless galvano-magnetro effect apparatus according to claim 1, wherein at least one resistance yoke, the width of which is gradually reduced from one electrode toward the other electrode, is provided.

Claim 6

A contactless galvano-magnetro effect apparatus according to claim 1, wherein a circular magnetro-resistance effect device is provided with three electrodes and is divided into three resistance yokes, two of the electrodes being connectable between the remaining intermediate electrode and the power supply, so as to be parallel with one of two resistance yokes which has the intermediate electrode at one end, and a magnetic field applying means which is positioned opposite to one of two resistance yokes divided by the intermediate electrode.

Claim 7

A contactless galvano-magnetro effect apparatus according to claim 5, wherein the flux density of the magnetic field applied to the two resistance yokes which are divided by the intermediate electrode is alternately varied.

Claim 8

A contactless galvano-magnetro effect apparatus according to claim 1, wherein a circular device is provided with four electrodes and is divided into four resistance yokes, the power supply being connected to two of the four electrodes which extend opposite from each other, the load being connected to the remaining two electrodes, and the resulting bridge circuit, which consists of the four resistance yokes, is unbalanced by varying the flux density of the magnetic field applied to one of the resistance yokes, and the voltage is applied to the load.

Claim 9

A contactless galvano-magnetro effect apparatus according to claim 7, wherein the flux density of the magnetic field applied to the two resistance yokes corresponding to the two opposite yokes of the bridge circuit is varied at the same time.

Claim 10

A contactless galvano-magnetro effect apparatus according to claim 7 wherein the load connected to the bridge circuit is a resonance circuit consisting of a variable capacity diode, which varies its capacity in accordance with voltage, and an inductance coil and the bridge circuit are controlled so that the output characteristics gradually increase or decrease with a variation of the flux density of the magnetic field.

Claim 11

A contactless galvano-magnetro effect apparatus according to claim 9, wherein a gate device and a diode for the gate with Zener characteristics are series-connected between the intermediate point of the coil of the resonance circuit and the output terminal of the bridge circuit, the gate device operating to cause the diode for the gate to be conductive and the intermediate point of the coil being short-circuited to the output terminal of the bridge circuit when the flux density of the magnetic field changes into a specified pattern.

Claim 12

A contactless galvano-magnetro effect apparatus according to claim 10, including a rotary shaft wherein a rotary magnet, energized in the direction of thickness, is provided with at least one non-energized portion in the radial direction and rotates in parallel with the device, a rotary plate, to which the magnet is fixed, is mounted to the same rotary shaft, and a fixed support plate is provided with at least one galvano-magnetro effect device as the gate device and is arranged opposite to the rotary plate, the magnetic flux from the magnet on the rotary plate being concentrated onto the gate device of the support plate when the non-energized portion of the rotary magnet comes to a position opposite to a specified position of a specific resistance yoke of the device.

Claim 13

A contactless galvano-magnetro effect apparatus according to claim 1, wherein a rotary magnet is energized in the direction of thickness and is provided with at least one non-energized portion in the radial direction so that the non-energized portion moves opposite to the resistance yoke of the device.