JPH11257967A - Angular velocity sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an angular velocity sensor which can prevent electromagnetic waves from reaching electronic components of a circuit board and stabilize an output signal of the angular velocity sensor. SOLUTION: A box type shielding case 17 made of metal which accommodates an inner case 15 accommodating a circuit board 13 on which an electronic component 14 is mounted, and has an aperture part 17a in a part, and a lid 18 made of metal which closes hermetically the aperture part 17a of the shielding case 17 are installed. Hence noise signals do not reach the electronic component 14 on the circuit board 13 from outside the shielding case 17 and the lid 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an angular velocity sensor used for attitude control of a moving body such as an aircraft or a vehicle, a navigation system, and the like.

[0002]

2. Description of the Related Art A conventional angular velocity sensor of this type includes:
This will be described with reference to the drawings. FIG. 6 is an exploded perspective view of a conventional angular velocity sensor.

In FIG. 6, reference numeral 1 denotes a tuning fork. The tuning fork 1 includes a metal block 1a and a pair of flat plate-like driving portions 1b each having one end fixed to the metal block 1a and provided so as to face each other. And this pair of driving units 1
and a pair of flat plate-like detecting portions 1c which are connected so as to protrude from the other end of the driving portion 1b and are provided so as to have the direction of the surface orthogonal to the direction of the surface of the driving portion 1b. . Reference numeral 2 denotes a metal weight plate for fixing the tuning fork 1 to the lower surface.
a is fixed. Reference numeral 3 denotes a circuit board.
Is provided on the upper surface of the weight plate 2 so as to be in contact with the weight plate 2, and an electronic component 4 for processing an output voltage generated from the tuning fork portion 1 by an angular velocity is provided on the upper surface. Reference numeral 5 denotes a resin case having an open upper surface. The case 5 accommodates the tuning fork 1, the weight plate 2, and the circuit board 3 so as to be supported by the rubber body 2a. Reference numeral 6 denotes a lid made of resin. The lid 6 is provided with terminals 7 electrically connected to the electronic components 4 of the circuit board 3 so as to protrude from side surfaces.

[0004] Next, the operation of the conventional angular velocity sensor configured as described above will be described.

When the tuning fork 1 rotates at an angular velocity ω about the longitudinal center axis of the tuning fork 1 in a state where the driving portion 1b of the tuning fork 1 is bending and vibrating at a speed V, the tuning fork 1 Coriolis force of F = 2 mVω is generated in the detection unit 1c. Due to this Coriolis force, the detecting portion 1c of the tuning fork 1
Then, the charge is converted into an output signal by the electronic component 4 provided on the circuit board 3 and is output from the terminal 7 of the lid 6 to an external partner computer or the like.

[0006]

However, in the above-mentioned conventional configuration, since the case 5 and the lid 6 are made of resin, the electromagnetic wave existing in the air is not affected by the circuit board 3.
And the noise signal is added to the output signal, and the output signal of the angular velocity sensor becomes unstable.

An object of the present invention is to provide an angular velocity sensor capable of preventing electromagnetic waves from reaching electronic components on a circuit board and stabilizing an output signal of the angular velocity sensor. It is intended to provide.

[0008]

In order to achieve the above object, an angular velocity sensor according to the present invention comprises a tuning fork, a weight plate for fixing the tuning fork to a lower surface, and a weight plate on the upper surface of the weight plate. A circuit board provided on the upper surface and provided with electronic components for processing an output voltage generated by the angular velocity from the tuning fork, and the tuning fork, the weight plate, and the circuit board are housed, and an opening is partially formed. An inner case provided, an inner cover for closing an opening of the inner case, and a terminal electrically connected to an electronic component of the circuit board protruding outward; and an inner case and an inner cover. And a metal box-shaped shield case provided with an opening in a part thereof, and a lid for closing the opening of the shield case so as to seal the opening, and the lid is made of metal. Providing at least three terminal insertion hole in the lid, and a separate terminal to which the terminal and the one end portion is electrically connected to the terminal insertion hole is inserted through an insulator,
Furthermore, the other end of this separate terminal is made to protrude outside from the lid. According to this configuration, it is possible to prevent the electromagnetic wave from reaching the electronic components of the circuit board, and the output signal of the angular velocity sensor can be prevented. Can be stabilized.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention provides a tuning fork portion, a weight plate for fixing the tuning fork portion to a lower surface, and an upper surface of the weight plate which is in contact with the weight plate. A circuit board provided on an upper surface with electronic components for processing an output voltage generated by the angular velocity from the tuning fork, and an inner case accommodating the tuning fork, the weight plate, and the circuit board and partially providing an opening. And an inner lid that closes an opening of the inner case and is provided so as to protrude outwardly a terminal electrically connected to the electronic component of the circuit board, and stores the inner case and the inner lid, A metal box-shaped shield case provided with an opening in a part thereof; and a lid for closing the opening of the shield case so as to seal the opening. The lid is made of metal, and at least 3 Horn The terminal insertion hole is provided, and a separate terminal having one end electrically connected to the terminal is inserted through the terminal insertion hole via an insulator. According to this configuration, the inner case and the inner lid for accommodating the circuit board are sealed with a metal shield case and a metal lid. The noise signal does not arrive from the outside of the case and the lid.

According to a second aspect of the present invention, a recess is provided on the outer surface of the lid so as to surround at least three terminal insertion holes, and the other end of the separate terminal is bent in the recess. According to the above, after mounting by soldering a separate terminal to the mating substrate, the separate terminal shrinks due to a change in ambient temperature, and even if stress is applied to the separate terminal itself, the external terminal side of the lid Since the other end of the separate terminal is bent in the provided recess, the stress applied to the separate terminal can be absorbed by this bending, and as a result, direct stress is not applied to the soldered portion. It has an action.

According to a third aspect of the present invention, the insulator is made of a glass material. According to this structure, a noise signal is likely to reach the inside of the angular velocity sensor through a separate terminal from the outside of the shield case. Also, since the glass material becomes a high-pass filter, the noise signal escapes from the lid to the shield case via the insulator made of glass, and as a result, the noise signal does not reach the circuit board. It has.

Hereinafter, an angular velocity sensor according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of an angular velocity sensor according to an embodiment of the present invention. FIG. 2 is a perspective view of a shield case as a main part of the angular velocity sensor, FIG. 3 is a perspective view of a lid as the main part, and FIG. 4 is a side sectional view of the lid.

In FIG. 1 to FIG. 4, reference numeral 11 denotes a tuning fork. The tuning fork 11 includes a metal block 11a and a pair of flat plate-like driving members having one end fixed to the metal block 11a and provided so as to face each other. And a pair of flat plate-shaped members that are connected so as to protrude from the other end of the pair of drive units 11b, and that are provided so as to be oriented in the direction perpendicular to the direction of the surface of the drive unit 11b. And a detection unit 11c. Reference numeral 12 denotes a metal weight plate. The weight plate 12 fixes the tuning fork portion 11 to the lower surface, and has rubber members 12a fixed to four corners of the weight plate 12. Reference numeral 13 denotes a circuit board. The circuit board 13 is provided on the upper surface of the weight plate 12 so as to be in contact with the weight plate 12, and includes an electronic component 14 for processing an output voltage generated from the tuning fork portion 11 by an angular velocity. It is provided on the upper surface. 15 is an opening 1 on the upper surface
The inner case 15 accommodates the tuning fork 11, the weight plate 12, and the circuit board 13 so as to be supported on the inner surface via the rubber body 12a. An anti-vibration sheet 15b is attached to the side surface. Reference numeral 16 denotes an inner lid made of resin. The inner lid 16 closes an opening 15a of the inner case 15 and a terminal 16a electrically connected to the electronic component 14 of the circuit board 13.
Are provided so as to protrude outward. Reference numeral 17 denotes a metal box-shaped shield case provided with an opening 17a on the upper surface.
6 are stored. Reference numeral 18 denotes a metal lid, which is closed so as to seal the opening 17a of the shield case 17. The lid 18 is provided with at least three terminal insertion holes 19, and a separate terminal 20, which is electrically connected to the terminal 16 a of the inner lid 16 at one end, is formed of a glass material. The separate terminal 20 is inserted through an insulator 21, and the other end of the separate terminal 20 projects outward from the lid 18. And this lid 18
Is provided with a concave portion 22 surrounding the terminal insertion hole 19, and the separate terminal 20 is bent in the concave portion 22.

Next, an assembling method of the angular velocity sensor according to the embodiment of the present invention configured as described above will be described.

First, the tuning fork 1 previously assembled
1 is fixed to the lower surface of the weight plate 12, and a circuit board 13 on which an electronic component 14 is mounted in advance is bonded to the upper surface of the weight plate 12.

Next, the tuning fork 11, the weight plate 12, and the circuit board 13 are housed in the inner case 15 so as to be supported on the inner surface of the inner case 15 via the rubber body 12a.

Next, the opening 1 of the inner case 15 accommodating the tuning fork 11, the weight plate 12, and the circuit board 13 is described.
5a is closed by the inner lid 16 so that the terminal 16a of the inner lid 16 and the electronic component 14 of the circuit board 13 are electrically connected.

Next, an anti-vibration sheet 15b is attached to the outer surface of the inner case 15. Next, the inner case 15 and the inner lid 16 provided with the tuning fork 11, the circuit board 13, and the weight plate 12 are housed in the shield case 17.

Finally, the opening 17a of the shield case 17 is closed and sealed with the lid 18 so that the terminal 16a of the inner lid 16 and the separate terminal 20 provided on the lid 18 are electrically connected.

Next, the operation of the angular velocity sensor according to the embodiment of the present invention assembled as described above will be described.

In a state where the driving portion 11b of the tuning fork portion 11 bends and vibrates at a speed V in the driving direction, the tuning fork portion 11
When the tuning fork 11 rotates around the central axis in the longitudinal direction at an angular velocity ω, the detecting portion 11c of the tuning fork 11 has F = 2 m
A Coriolis force of Vω is generated. Due to this Coriolis force, an electric charge is generated in the detection unit 11c, and this electric charge is converted into an output signal by the electronic component 14 of the circuit board 13, and this output signal is separated into a terminal 16a of the inner lid 16 and a separate The data is output to the other computer or the like via the terminal 20. At this time, since the shield case 17 and the cover 18 are made of metal, even if an electromagnetic wave existing in the air tries to reach the electronic component 14 of the circuit board 13, the shield case 17 and the cover 18 are grounded, Since the noise signal is cut off, there is an effect that the electromagnetic wave does not reach the circuit board 13.

Further, since the insulator 21 provided in the terminal insertion hole 19 of the cover 18 is made of a glass material, a noise signal is transmitted from the outside of the shield case 17 and the cover 18 to the separate terminal 20. Even if it tries to reach the inside of the angular velocity sensor, since the insulator 21 made of the glass material becomes a high-pass filter, the noise signal must escape from the lid 18 to the shield case 17 via the insulator 21 made of the glass material. As a result, there is an effect that the noise signal is prevented from reaching the electronic component 14 of the circuit board 13.

When the angular velocity sensor according to one embodiment of the present invention is mounted on a mating substrate, as shown in FIG. 5, a separate terminal 20 is mounted on the mating substrate 23 by soldering. . After this mounting, even if the separate terminal 20 contracts due to a change in the ambient temperature and stress is applied to the separate terminal 20 itself, the separate terminal 20 is placed in the recess 22 provided on the outer surface side of the lid 18. Since the ends are bent, the stress applied to the separate terminals 20 can be absorbed by the bending, and as a result, the soldered portions 24
Since the stress is not directly applied to the angular velocity sensor, the output characteristics of the angular velocity sensor are stabilized.

[0025]

As described above, the angular velocity sensor of the present invention
A tuning fork portion, a weight plate for fixing the tuning fork portion to the lower surface,
A circuit board provided on the upper surface of the weight plate so as to be in contact with the weight plate, and an electronic component for processing an output voltage generated from the tuning fork by the angular velocity provided on the upper surface; the tuning fork portion, the weight portion, and the circuit board And an inner case provided with an opening in a part thereof, and a terminal electrically closed to the opening of the inner case and electrically connected to the electronic component of the circuit board provided to protrude outward. An inner lid, a metal box-shaped shield case that houses the inner case and the inner lid, and has an opening in a part thereof, and a lid that closes the opening of the shield case so as to seal the opening. The cover is made of metal, and at least three terminal insertion holes are provided in the cover, and separate terminals, one end of which is electrically connected to the terminal, are inserted into the terminal insertion holes via an insulator. Further, the other end of the separate terminal is made to protrude outside from the lid so that the inner case and the inner lid for housing the circuit board are sealed with a metal shield case and a metal lid. Therefore, the noise signal does not reach the electronic components of the circuit board from outside the shield case and the lid, and as a result, an excellent effect that the output signal can be stabilized is achieved.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an angular velocity sensor according to an embodiment of the present invention.

FIG. 2 is a perspective view of a shield case which is a main part of the angular velocity sensor.

FIG. 3 is a perspective view of a lid which is a main part of the same.

FIG. 4 is a side sectional view of the lid.

FIG. 5 is a side sectional view showing a state in which the angular velocity sensor according to one embodiment of the present invention is mounted on a mating substrate;

FIG. 6 is an exploded perspective view of a conventional angular velocity sensor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Tuning fork part 12 Weight board 13 Circuit board 14 Electronic component 15 Inner case 15a Opening 16 Inner lid 16a Terminal 17 Shield case 17a Opening 18 Cover 19 Terminal insertion hole 20 Separate terminal 21 Insulator 22 Recess

Claims (3)

[Claims] 1. A tuning fork portion, a weight plate for fixing the tuning fork portion to a lower surface, and an upper surface of the weight plate provided to be in contact with the weight plate and for processing an output voltage generated from the tuning fork portion by an angular velocity. A circuit board provided with an electronic component to be provided on the upper surface, an inner case accommodating the tuning fork, the weight plate, and the circuit board and having an opening provided in a part thereof; An inner lid provided so as to protrude outwardly a terminal electrically connected to the electronic component of the board, and a metal box-shaped housing the inner case and the inner lid, and partially having an opening. And a cover for closing the opening of the shield case so as to seal the opening. The cover is made of metal, and at least three terminal insertion holes are provided in the cover. An angular velocity sensor in which a separate terminal having one end electrically connected to the terminal is inserted through an insulator, and the other end of the separate terminal is projected outside the lid. 2. The angular velocity sensor according to claim 1, wherein a recess is provided on the outer surface of the lid so as to surround at least three terminal insertion holes, and the other end of the separate terminal is bent in the recess. 3. The angular velocity sensor according to claim 1, wherein the insulator is made of a glass material.