JPS6344121A - Bearing/electric signal converter - Google Patents

Abstract

PURPOSE:To obtain an easy-to-handle bearing-to-electric-signal converter with excellent sensitivity and directivity by mounting bar-shaped ferromagnetic bodies to which means for correcting the unbalanced output of a Hall element and demagnetizing a remanent magnetism is added to the magnetism detecting surfaces of the Hall element. CONSTITUTION:Bar-shaped ferromagnetic bodies 2 made of such a material as ferrite are fixedly attached to both magnetism detecting surfaces of a Hall element 1 perpendicularly to the magnetism detecting surfaces. A coil 3 for generating a prescribed magnetic field for canceling the unbalanced output of the element 1 and the coil 3 for letting a dampedly oscillating current for demagnetizing an unnecessary magnetism in the ferromagnetic bodies 2 flow are wound around them. A connection is performed such that the bearing-to-electric-signal converted output of the element 1 takes a maximum (or minimum) value when a magnetic field detecting direction is directed to a magnetic pole N (or S). Thus, a bearing can be known from a relationship between the magnetic field detecting direction relative to the direction of the terrestrial earth magnetism and the output of the element 1. When a strong magnetism is received from outside, a remanent magnetism lets DC current and damping oscillation current flow 4 in the coil 3 to cancel the strong magnetism. Accordingly, the bearing can be converted to electric signals with a high accuracy.

Description

[Detailed Description of the Invention] (Using Molecules of J-I-L?) The present invention is based on the f-stage of the Hall element for magnetic correction, which performs functions such as canceling the unbalanced net output and demagnetizing the ferromagnetic material. This relates to an azimuth-to-electrical signal converter.

(Prior technology) Satoshi's magnetic needle force (Q direction detector and remote control when Nido cannot be used, instructions,
For recording, etc., what is detected as a total azimuth electric signal is a combination of a rotating magnetic needle and various types of 7/cers (Ml) (167913/1985, 36685/1985), an excitation coil coil in a magnetic core. , with a detection coil wound around it,
(Real 15A 1986-144578. Unexamined closed 6O-141
15) A combination of a Hall element and a ferromagnetic material,
(Showa 6 o-s + 49 to) Although there is a beginning of tv, these forces (Q detector has a rotating part, so its durability is low, it takes a long time to detect, 1 magnet is required, and the structure is complicated. There are problems such as deterioration of electric signal conversion performance when the magnetic head is exposed to a strong magnetic field during use and residual magnetism is generated.

(Problems to be Solved by Detector 1gI) The present invention uses known Hall elements, magnetoresistive elements, etc. as solid-state elements that detect magnetism and convert it into magnetic signals. To stably detect the earth's magnetism, sensitivity,
Focusing on the directivity of 74, we installed a rod-shaped ferromagnetic material on the magnetic detection surface (with a means for correcting unbalanced output and demagnetizing residual magnetism) on the magnetic detection surface (-1), making it easy to handle. The purpose of this invention is to obtain an azimuth-to-electrical signal converter with good sensitivity and directivity.

(Means for Solving the Problems) In order to achieve the object of item 1, the configuration of the present invention will be explained with reference to FIGS. 1 and 2 corresponding to the embodiment. In this method, a rod-shaped ferromagnetic material such as ferrite is fixed to both magnetic detection surfaces of the Hall element so as to be perpendicular to the magnetic detection surfaces of the Hall element, and the unbalanced output of the Hall element is fixed to the ferromagnetic material. It consists of a coil that generates a constant magnetic field for cancellation, and a coil that flows a damped oscillating current to demagnetize the unnecessary magnetization of the ferromagnetic material.

Note that the coils for canceling and demagnetizing the unbalanced output may be used in common, or may be used in common as part of the damped oscillating current generation circuit.

(Function) In the azimuth-'FtL% signal converter of the present invention, the azimuth-electrical signal conversion output of the Hall element f- has a maximum value of +V when the magnetic field detection direction is toward the N magnetic pole, and a minimum value of +V toward the S magnetic pole. −■
By connecting the wires in such a manner, the direction can be determined from the relationship between the magnetic field detection direction of the converter with respect to earth's magnetism and the nuclear Hall element output.

For example, if the output of the Hall element is in the direction of +V (the direction of the magnetic field detection direction of the converter), that direction is north,
If rotated clockwise from there, the output decreases by an order of magnitude. The position where the output becomes +Hy is the northeast, and the position where the output becomes 0 is the east.

Further, when the output is -MV, the direction is southeast, and when the output is -■, the direction is south. However, the Hall element produces an unimpinged output even in the absence of an external magnetic field or in a position where the magnetic detection surface is perpendicular to the magnetic field. To counter this, a weak direct current is passed through the coil to generate a magnetic field with a direction and magnitude that cancels out the unbalanced output.

Also, if a strong magnetism is received from the outside, the remaining ferromagnetic material
! (Unbalanced output due to the a-field occurs, causing distortion in the detection output for each direction. Therefore, a damped oscillating current is passed through the coil to perform demagnetization in a timely manner.

Magnetic correction as described above allows highly accurate azimuth-to-electrical signal conversion. The unimpinged output canceling and demagnetizing coil described above can also be used as a part of the damped vibration 1'tI current generating circuit as shown in FIG.

(Embodiment) FIG. 1 is a perspective view of a first embodiment of the azimuth-to-electrical signal converter of the present invention, and FIG. 2 is a wiring diagram.

In the drawing, 1 is a Hall element using an InSb vapor-deposited thin film, 2 is a ferromagnetic rod such as ferrite, and 3 is a coil.
The arrow points in the magnetic field detection direction, and the coil 3 is connected to a damped oscillating current generation and unimpinged output canceling DC current supply circuit 4. In the figure, C is a capacitor, R is a resistor, Sw is a switch, B is a battery, E is a Hall element control power source, and F is an azimuth-electrical signal conversion output terminal.

FIG. 3 is a perspective view of the second embodiment of the present invention, in which two azimuth-to-electrical signal converters A and B are arranged so that each magnetic field detection direction axis is 99° in a horizontal plane.
They are arranged to cross 0'. According to this example, an accurate direction can be quickly detected from the combination of both receivers AB and the AB output relationship shown in FIG. Also, it is not necessary to install both detectors on top of each other as shown in the figure.
They may be installed separately in appropriate locations.

4 to 7 are output characteristic diagrams of the structure and members of the present invention, and FIG. 4 is a rotation angle of a single Hall element and a Hall element output voltage characteristic diagram.

Fig. 5 is a characteristic diagram of the rotation angle of the Hall element with a ferrite rod and the Hall element output voltage, Fig. 6 is a characteristic diagram of the coil ftfQ of the Hall element and the undrawn output voltage, and Fig. 7 is a characteristic diagram of the waveform of damped vibration. It is a figure showing an example.

Fig. 8 is a chart showing an example of experimental data of the output voltage before magnetization and after demagnetization of the converter of the present invention, and Fig. 9 is an explanatory diagram of the usage state of two f converters. Set each to output the maximum IV when the * mark is north. At this time, when the north position changes as shown in C, the outputs of A and B change as shown in the table on the right. This one combination is determined by which direction north is facing, so any 73rd place can be determined from the outputs of A and B.

(Effect of the invention) The present civilization direction-electrical signal converter has rotating and other i
j Since there is no pivoting part, the direction can be read quickly from the magnitude of the output electric signal, and there is no distortion during use, and the Hall element can be sufficiently amplified by a general-purpose OF amplifier for practical use. When the electrical output of the detection is obtained, the inherent negative impact output and the ferromagnetic -! The residual magnetic field generated when one body receives strong magnetism from the outside is canceled by the direct current and damped oscillating current flowing through the coils, respectively, so that effects such as highly accurate azimuth-to-electrical signal conversion are produced.

[Brief explanation of the drawing]

No. ifΔ is a perspective view of the first embodiment of the direction detection performance of the present invention. Figure 2 is a lll1 diagram, Figure 3 is a perspective view of the second example,
4 to 7 are respective output characteristic curves of the constituent members of the present invention, FIG. 8 is a chart of experimental data, and FIG. 9 is a chart for explaining the use fE of two converters. Hall element 2: Ferromagnetic material 3. Coil 4: DC current supply circuit that cancels damped vibrations and generates residue and insufficient drawing force. Figure 1

Claims (3)

[Claims] (1) A rod-shaped magnetic body is attached to both magnetic detection surfaces of the Hall element perpendicularly to the surfaces, and the ferromagnetic body has a magnetic effect such as canceling the unbalanced output of the Hall element and demagnetizing unnecessary magnetism of the ferromagnetic body. An azimuth-to-electrical signal converter consisting of a coil wound around for correction. (2) The azimuth-to-electrical signal converter according to claim 1, wherein a single coil is used for magnetic correction such as cancellation of the unimpinged output of the Hall element and demagnetization of the ferromagnetic material. (3) The azimuth-to-electrical signal converter according to claim 2, in which the coil described in claim 2 is shared as a part of the damped oscillating current generation circuit.