JPH0449069B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gimbal device that supports a magnetic sensor, etc. in a magnetometer. For example, in the field of earthquake prediction, earthquakes are predicted by measuring changes in the geomagnetic field. In this case, in order to measure changes in the earth's magnetic field, a gimbal device with a 3-axis magnetic sensor is installed on the ocean floor, etc., and the magnetic changes are measured, recorded in a magnetic memory, etc., and then retrieved and the contents analyzed. things are done.

Therefore, there is a conventional gimbal device used for such magnetic measurements as shown in Figs. c, an electronic circuit board d, a magnetic memory e, etc. are provided via a base f. Only this three-axis magnetic sensor b is supported via the gimbal device g.

This gimbal device g has a U-shaped support frame h fixed to a base f, a ring-shaped rotation frame i on this support frame h, and a 3-axis magnetic sensor b on this rotation frame i in orthogonal directions. is pivoted by pins j and k of
A weight l is attached to the lower part of this three-axis magnetic sensor b. Therefore, even if the container a is tilted, the magnetic sensor b rotates in a cross direction around the pins j and k and is maintained in a substantially horizontal state.

However, the gimbal device g only holds a 3-axis magnetic sensor b, and a power source c, an electronic circuit board d, etc. are provided around the 3-axis magnetic sensor b, so when the 3-axis magnetic sensor b moves, Its relative position with the surrounding magnetic material changes, and it is directly affected by this magnetic material. This poses a problem in that accurate magnetic measurements cannot be made.

Furthermore, the three-axis magnetic sensor b and the electronic circuit board d are connected via a lead wire m.
Since the axial magnetic sensor b moves, drawing out the lead wire m is extremely troublesome and is a cause of failure.

This invention has been made in view of the above, and includes a substantially hemispherical weight that is movably provided in a spherical container via a ball bearing, and a magnetic sensor, a power source, an electronic circuit board, and a magnetic memory. The present invention provides a gimbal device for a magnetometer, in which the magnetic sensor is not affected by other magnetic materials and the lead wire can be easily drawn out by installing and fixing the magnetic sensors in one piece.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

As shown in FIGS. 3 to 5, reference numeral 1 is a three-axis magnetometer that detects various magnetic changes on the seabed. , an electronic circuit board 6, a magnetic memory 7, and the like are housed therein. When the 3-axis magnetometer 1 is installed, for example, on the seabed, etc., it is installed on the seabed together with the self-levitation device 12, the pedestal 13, etc., as shown in FIG. 6, and after recording magnetic changes for a predetermined period, It is separated from the mount and recovered when it reaches the sea by a self-levitation device 12, and its contents are analyzed.

The container 2 is formed of a spherical glass container, and includes a lower hemispherical main body 2a and an upper hemispherical lid 2.
It is divided into two parts (b) and is configured to have a watertight structure due to self-closing action on the seabed or the like.

The gimbal device 3 is for holding the three-axis magnetic sensor 4 in a horizontal state, and is composed of a weight 8 installed on the container body 2a via a ball bearing 9. The weight 8 is formed into a substantially hemispherical shape by removing a part of a sphere having a diameter slightly smaller than that of the container 2, and has a spherical surface 8a on the lower surface and a flat surface 8b on the upper surface. Three ball bearings 9 are provided in a circular manner at the bottom of the spherical surface 8a. This ball bearing 9 protrudes from the spherical surface 8a of the weight 8, contacts the inner surface of the container body 2a, and supports the weight 8 so that it can move in any direction along the inner surface of the container 2.

The three-axis magnetic sensor 4 detects magnetic changes 3
It is an axial magnetic sensor, and the flat surface 8b of the weight 8
It is supported or locked by the pillar 11 etc. due to the shape,
It is integrally attached almost in the center. A power supply 5, an electronic circuit board 6, a magnetic memory 7, etc. are integrally mounted around the triaxial magnetic sensor 4 on the weight flat surface 8b. Further, the three-axis magnetic sensor 4 is connected to a power source 5 and an electronic circuit board 6 by a lead wire 10.

Therefore, if this 3-axis magnetometer 1 is installed on the seabed or the like and the container 2 is tilted, the weight 8 will try to move toward the bottom of the container 2, and if this force becomes larger than the frictional force of the ball bearing 9, , this weight 8 moves and comes to rest at a point of balance with the frictional force. By moving this weight 8,
The three-axis magnetic sensor 4 is also moved and kept in a horizontal state at all times, and at the same time, the other power supplies 5, electronic circuit board 6, magnetic memory 7, etc. are also moved and kept in a horizontal state. Therefore, the three-axis magnetic sensor 4 is held without changing its relative position to other electronic circuit boards 6 and the like.

Although this embodiment has been described with respect to the three-axis magnetometer 1, it goes without saying that the present invention can be applied to other magnetometers.

As described above, according to the present invention, a substantially hemispherical weight is movably provided in a spherical container via a ball bearing, and a magnetic sensor, a power source, an electronic circuit board, a magnetic memory, etc. are integrated on this weight. Since the magnetic sensor is installed and fixed, the relative positional relationship between the magnetic sensor and the surrounding magnetic material does not always change, so the magnetic sensor is not affected by the magnetic material, and highly accurate magnetic measurements can be performed. Furthermore, magnetic materials can be incorporated to some extent together with magnetic sensors.

In addition, since there is no need to pull out the lead wire that connects the magnetic sensor and the electronic circuit board etc. from the gimbal device, the structure is simplified and the work is extremely easy, and furthermore, failures etc. can be reliably prevented. Can be done.

[Brief explanation of the drawing]

Figures 1 and 2 show conventional examples,
Figure 1 is a plan view of the magnetometer with the upper part of the container omitted, Figure 2 is a vertical cross-sectional view of the same, Figures 3, 4 and 5.
The figures show an embodiment of the present invention, in which FIG. 3 is a plan view of the magnetometer with the container lid omitted, FIG. 4 is a central vertical cross-sectional view of the magnetometer, and FIG. 5 is a bottom view of the magnetometer with the container main body omitted.
FIG. 6 is a schematic diagram of an example of magnetometer installation. 1... Magnetometer, 2... Container, 2a... Main body, 2
b...Lid body, 3...Gimbal device, 4...3-axis magnetic sensor, 5...Power source, 6...Electronic circuit board, 7
... Magnetic memory, 8 ... Weight, 8a ... Spherical surface, 8b ... Flat surface, 9 ... Ball bearing,
10... Lead wire, 11... Strut, 12... Self-levitation device, 13... Frame.

Claims (1)

[Scope of Claims] 1. A magnetometer in which a magnetic sensor, a power source, an electronic circuit board, a magnetic memory, etc. are housed in a spherical container, comprising: a substantially hemispherical weight provided inside the container; A plurality of ball bearings are provided on the spherical side so that the weight is in contact with the container so that it can freely roll within the container, and the magnetic sensor is installed and fixed on the upper surface of the weight, and the magnetic sensor is fixed to the upper surface of the weight. On the other hand, a gimbal device for a magnetometer, characterized in that a power source, an electronic circuit board, and a magnetic memory are also installed and fixed on the upper surface of the weight so as not to change the positional relationship with the magnetic sensor.