JP3473416B2 - Magnetic detector - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic detector for measuring geomagnetism and the like, and more particularly to a magnetic detector having a two-axis gimbal mechanism. 2. Description of the Related Art FIG. 5 is a perspective view of a conventional magnetic detector, and FIG. 6 is a sectional view thereof. As shown in FIG. 5, the magnetic detection device includes a two-axis gimbal mechanism 2 in its casing 1a.
, A sensor main body 3 (magnetic sensor and signal processing circuit). The two-axis gimbal mechanism 2 includes a short axis 22 having a pair of opposed side frames of the frame body 21 provided with bearings, and a long axis 2 fixed to another pair of side frames in a direction perpendicular to the short axis 22.
3 and 23. Both ends of the long shaft 23 are, as shown in FIG.
6 is supported. The power supply lead wire 57 from the sensor body 3 taken out from the distal end 23 a of the long shaft 23 is connected to one end of the hair spring 5, and the other end is connected to a terminal 54.
Is relayed to the outside. Therefore, the sensor body 3 is moved by the two-axis gimbal mechanism 2 to the long axis 2.
3. The sensor body 3 is rotatable in both directions of the short axis 22.
Is always kept in the vertical direction by a weight 31 provided at its lower part. However, when transporting the magnetic detection device or installing it underwater, it is necessary to protect the sensor body 3 from vibration and impact, and therefore, a clamp mechanism 4 as shown in FIG. 5 is conventionally used. ing. [0004] The clamp mechanism 4 includes a stopper receiving plate 41 fixed to the long axis tip 23b of the biaxial gimbal mechanism 2;
A stopper 42 that moves back and forth in the long axis direction and presses against the stopper receiving plate 41 so as to be able to come into contact with and separate from the stopper receiving plate 41, and locks the rotation of the long shaft 23; It is composed of a motor 43d. The stopper 42 formed of a triangular flat plate has 3
As shown in FIG. 5, a screw hole 42c is provided at the top of each point, and a screw shaft 43c having a screw shaft gear 43b at its head is screwed into the screw hole 42c. Further, the screw shaft gear 43b is screwed with a gear 43e fixed to the motor rotation shaft via a relay large gear 43a. Therefore,
When the motor 43d is rotated, the screw shaft 43c rotates, and at the same time, the stopper 42 linearly moves in the long axis direction. Then, the stopper 42 comes into pressure contact with the opposing stopper receiving plate 41, and the rotation of the sensor main body 3 in the short axis direction is prevented. The rotation in the long axis direction is limited by the frame 21 that supports the short axis, but the accommodation chamber 1 that accommodates the clamp mechanism 4 shown in FIG.
3. accommodation chamber 12 for accommodating the biaxial gimbal mechanism 2 for vertically suspending the sensor body 3, bellows 15, and hair spring 5
Of the sensor body 3 is protected from vibrations and impacts by filling the shock absorbing oil 6 with the box body 51 that accommodates the sensor body 3. [0005] The conventional magnetic detecting device is constructed as described above. However, as shown in FIG. 6, a clamp mechanism 4 of a sensor body 3 has a stopper receiver fixed to a long axis. Since the stopper 42 is pressed against the plate 41 in one direction of the long axis 23, there is a problem that an excessive thrust load is applied to the bearings provided at both ends of the long axis to damage the bearings. Further, in order to suppress the movement of the sensor in the long axis direction, oil is sealed to reduce the friction coefficient of the clamp mechanism, so that the clamp function is weakened, and the stopper receiving plate is provided with a larger pressing force. Have to be pressed into contact with each other, and it takes a lot of time to remove oil in case of failure or to fill oil after repair. In order to solve the above problem, as shown in FIG. 7, a disc brake plate 44 fixed to an end of the long shaft 23 is rotated by a motor 43d so that a clamp shaft 44d is rotated by a motor 43d. Driven in a direction opposite to each other in the long axis direction, sandwiched and pressed by a pair of clamp plates 44a and 44b to which a rubber ring is fixed, clamp the rotation by the frictional force, and provide a sensor in the long axis direction. For the rotation of, a method has been proposed in which a rubber cushion 32 is wound around the sensor body 3 to reduce the collision with the frame 21. However, in such a method for preventing rotation in the long axis direction due to frictional force, if a large shock exceeding 30 G is received during transportation, slippage occurs between the disc brake plate 44 and the clamp plates 44a, 44b. In some cases, rotation deviation cannot be prevented. To prevent this, it is necessary to increase the frictional force by using a motor with a larger torque, but this requires a large drive current, which causes a problem that the generated magnetic field increases and the magnetic detection sensitivity decreases. . [0009] The present invention has been made in view of such circumstances, and uses a motor having a small drive current to provide:
An object of the present invention is to provide a magnetic detection device having high magnetic detection sensitivity that can withstand a large impact force. [0010] In order to achieve the above object, a magnetic detection device according to the present invention comprises a two-axis gimbal mechanism comprising a short axis and a long axis disposed at right angles to the short axis. A magnetic sensor and a sensor main body having a signal processing circuit built therein are vertically mounted on a short axis of the magnetic detection apparatus, and the two-axis gimbal mechanism is attached orthogonal to a long axis end of the two-axis gimbal mechanism and has a cutout portion at an outer edge thereof. A disk brake plate and a clamp mechanism comprising a pair of clamp plates which reciprocate in a direction opposite to each other in the long axis direction, and a pair of clamp plates to which a cushion material for locking the rotation of the long axis is sandwiched by sandwiching the disk brake plate. It is. The magnetic detecting device of the present invention is configured as described above, and can use a motor having a small driving current to obtain a magnetic detecting device with high magnetic detection sensitivity that can withstand a large impact force. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the magnetic detecting device according to the present invention will be described below with reference to FIGS. FIG. 1 is a schematic perspective view of the magnetic detection device, FIG. 2 is a cross-sectional view thereof, and FIG. As shown in FIG. 2, the circular block 11a,
A sensor body 3 containing a two-axis gimbal mechanism 2, a magnetic sensor supported by the two-axis gimbal mechanism 2, and a magnetic sensor and a processing circuit thereof in a functional area 12 formed by a frame assembly 1 composed of 11b, 11c and four connecting rods 11d, 11e. Is provided, the clamp mechanism 4 is provided in the right functional area 13, and the left functional area 1 is provided.
4 are provided with hair springs 5 for power supply. As shown in FIG. 1, the two-axis gimbal mechanism 2 has long axes 23, 23 projecting from a rectangular frame 21, and both ends of the long axis 23 are respectively connected to the circular blocks 11a, 11a.
It is supported by bearings 16, 16 arranged in 1b. One end 23 a of the long shaft 23 penetrating the bearings 16, 16 is connected to the hair spring 5 of the functional area 14. On the other hand, the distal end portion 23b protrudes into the functional area 13, and a disc brake plate 44 described later is fixed to the protruding end. The other end of the hair spring 5 provided in the functional area 14 is connected to a terminal 54 and is taken out through a lead 56 to the outside. On the other hand, the long axis 23 on the distal end 23a side is connected to the sensor main body 3 via the lead 57 so that power is supplied from the outside. A feature of the present invention is that, as shown in FIG. 2, a disc brake plate 44 provided with a notch at the outer edge portion at the tip 23b of the long shaft 23, and a rubber plate provided at a position facing the notch. Elastic member 44e having appropriate elasticity such as
The pair of clamp plates 44a and 44b, to which the disc brake plates 4a and 4b are fixed, are advanced and retracted in opposite directions in the longitudinal direction.
4 between the elastic member 44e and the disc brake plate 44, the impact force is absorbed by the elastic member 44e pressed into the notch of the disc brake plate 44.
The rotation of the long shaft 23 is locked by the frictional force therebetween. As the disc brake plate 44, a non-magnetic metal disk of about 0.5 mm is used, and the clamp plates 44a and 44b are provided with a screw hole at the center and a small hole near the outer edge for passing the rotation stopper 44c. . As shown in FIG. 3, the driving mechanism 43 has a right-hand screw on the left side from the center of the screw shaft and a left-hand screw on the right side, and the clamp plate 44a,
44b and the clamp shaft 44d is connected to the electrostrictive motor 43.
It is driven by d. When the clamp shaft 44d rotates by the driving of the electrostrictive motor 43d, the clamp plate 44a
Moves rightward, and the clamp plate 44b moves leftward.
Then, the two clamp plates sandwich the disc brake plate 44 and come into pressure contact from both sides to prevent the rotation of the long shaft 23. At this time, elastic members such as rubber fixed to the clamp plates 44a and 44b are press-fitted from both sides of the cutout portion of the outer edge portion of the disc brake plate 44 to prevent the disc brake plate 44 from rotating. Do not apply a thrust load to the part. Note that the rotation range of the sensor body 3 in the long axis direction is limited by the frame 21 that supports the short axis 22, and the cushion 32 wound around the sensor body 3 prevents vibration and impact. Is protected. The disc brake plate 44 includes:
As shown in FIG. 4, a disk having a large number of holes provided on the inside of the outer peripheral portion can be used, thereby improving the workability. When the sensor body 3 is clamped by the clamp mechanism 4 of the above invention and is transported or dropped on the seabed, the sensor body 3 is completely protected from vibration and impact. When the installation surface is flat or parallel to the long axis direction of the biaxial gimbal 2 of the magnetic detection device, the sensor body 3 can be rotated only by the free short shaft 22 without releasing the clamping means. Is always located vertically. In addition, when the long axis direction and the inclination angle of the magnetic detection device are not parallel and are inclined obliquely, the rotation of the sensor body 3 in the short axis direction is free, and the time when the sensor body 3 is in the vertical state To operate the clamp mechanism 4 again to lock the rotation of the long shaft. In this case, since the clamp mechanism 4 locks the sensor main body 3 in a state parallel to the long axis 23, the sensor main body 3 can be locked in a vertical state regardless of how the installation surface is inclined,
Accurate magnetic detection becomes possible. The magnetic detecting device of the present invention is constructed as described above, and rotates the long axis of the two-axis gimbal mechanism by rotating the disk brake plate fixed to the long axis in parallel with the long axis. It is a method of locking by inserting an elastic member such as rubber into the cut portion, and has sufficient strength against a large impact force, and the magnetic detection surface has any inclined surface. Even in this case, the sensor main body can be always localized in the vertical direction, and the detection accuracy can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing one embodiment of a magnetic detection device of the present invention. FIG. 2 is a sectional view showing one embodiment of the magnetic detection device of the present invention. FIG. 3 is an assembly view of a main part of the present invention. FIG. 4 is another embodiment of the disc brake plate. FIG. 5 is a perspective view of a conventional magnetic detection device. FIG. 6 is a cross-sectional view of a conventional magnetic detection device. FIG. 7 is a perspective view of another conventional magnetic detection device. DESCRIPTION OF SYMBOLS 1 ... Frame assembly 1a ... Casing 2 ... Two-axis gimbal mechanism 3 ... Sensor body 4 ... Clamp mechanism 5 ... Hair spring 6 ... Oil 11a, 11b , 11c ... circular blocks 11d, 11e ... connecting rods 12, 13, 14 ... functional area 15 ... bellows 16 ... bearing part 17 ... through hole 21 ... frame 22 ··· Short axis 23 ··· Long axes 23a and 23b ··· Tip 31 ··· Weight 32 ··· Cushion 41 ··· Stopper receiving plate 42 ··· Stopper 42c ··· Screw hole 43 ··· Drive mechanism 43a Large relay gear 43d Motor 43e Gear 44 Disk brake plates 44a and 44b Clamp plate 44c Rotation stop 44d Clamp shaft 44e Elastic member 51 ... Box 54 ... Terminals 56 and 57 ... Lead

────────────────────────────────────────────────── (5) References JP-A-5-150024 (JP, A) JP-A-2-77688 (JP, U) JP-A-57-205095 (JP, U) Patent 316674 (JP, A) B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) G01C 17/00-17/38 G01R 33/00-33/26 G01V 1/00-13/00

Claims (1)

(57) Claims 1. A magnetic sensor and its signal processing circuit are built in a short axis of a two-axis gimbal mechanism including a short axis and a long axis arranged at right angles to the short axis. A disk brake plate which is mounted perpendicular to the long axis end of the two-axis gimbal mechanism and has a cut-out portion at an outer edge thereof, in a direction opposite to the long axis direction. A magnetic detecting device comprising: a pair of clamp plates, which reciprocate and sandwich a disk brake plate, to which a cushion member for locking the rotation of a long axis is fixed.