JPH0613971B2 - Angular velocity sensor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an angular velocity sensor used in a gyroscope and the like.

2. Description of the Related Art In a conventional angular velocity sensor, usually, as shown in FIG. 2, the wire 28 is directly pulled out from the piezoelectric bimorph 21 for detection, or
As shown in FIG. 3, the wire 28 was adhered with the adhesive 31. Incidentally, in FIG.
Is a driving piezoelectric bimorph element, 27 is a coupling member, 29 is a lead pin, and 30 is a base.

Problems to be Solved by the Invention In the wire wiring as shown in FIG. 2, the detection piezoelectric bimorph element 21 has no point of vibration. Therefore,
Since the wire 28 always vibrates at the connection point with the detection bimorph element 21, there is a risk of disconnection in long-term use. Also, since the wire 28 vibrates, electric charges are generated due to friction and noise is generated. May be.

On the other hand, if wire wiring is performed as shown in FIG. 3, the amplitude at the coupling member 26 can be ignored, but the wire 28
Is not applied to the side surface of the driving bimorph 24, resulting in an expensive angular velocity sensor.

The present invention intends to provide an angular velocity sensor capable of solving such problems.

Means for Solving the Problems The angular velocity sensor of the present invention has a driving piezoelectric bimorph element and a detection bimorph element, and an electrode composed of two signal lines having substantially equal areas is provided on the driving piezoelectric bimorph element. In addition, this electrode is used as a signal line of the detecting piezoelectric bimorph element.

Action With the above configuration, the risk of wire breakage and wire bonding work are reduced.

Embodiment FIG. 1 is a perspective view showing an embodiment of the angular velocity sensor of the present invention. In FIG. 1, reference numeral 4 denotes a driving piezoelectric bimorph element, which uses an electrode electrically and mechanically coupled to the coupling member 6 as a ground electrode, and has a driving electrode 5b and a pair of effective electrodes on opposite surfaces. There are signal lines 5a and 5c having substantially equal areas. The signal lines 5 are electrically coupled to the electrodes of the detection piezoelectric bimorph element 1 via the conductors 3 provided on the joining members 2, respectively. In the figure, 2 is a coupling member, 7 is a metal elastic member, 8 is a wire, 9 is a lead pin, 10 is a base, 11 is a conductive adhesive, and 12 is a detection shaft.

Below, only one side will be described as left-right symmetry.
The wires 5 are electrically coupled to the lead pins 9 through the wires 8, respectively. In order to automate the wire bonding, the wires 8 are bonded to the side surfaces of the driving bimorph element 4, and the tips of the wires 8 are connected to the lead pins 9. This is much easier than automating the soldering process. Further, due to the vibration of the driving piezoelectric bimorph element 4, the signal line 5
Electric charges are generated, but since the effective areas of the electrodes are made equal to each other, the generated electric charges are equal, so that noise generated in the signal line due to driving can be reduced by performing differential amplification in signal processing. .

In this embodiment, the conductor 3 is on the surface of the joining member 2, but it can be embedded inside the joining member 2. Also,
Although the conductive adhesive 11 is used for each electrode and the conductor,
Any combination method may be used.

EFFECTS OF THE INVENTION According to the present invention, the driving piezoelectric bimorph element is provided with an electrode composed of two signal lines having substantially the same area, and this electrode is used as the signal line of the detection piezoelectric bimorph element. Since the electric charge can be neutralized by the signal line and the signal line can be arranged on the piezoelectric body, an angular velocity sensor having a simple structure and improved noise resistance can be provided. Furthermore, by using the electrode of the driving bimorph element as the signal line of the piezoelectric bimorph element for detection, the risk of disconnection of the lead wire and the complicated work of adhering the lead wire are eliminated, and the effective area of the electrode used as the signal line is eliminated. The noise resistance is also improved by making the values equal to each other, and by providing a conductor in the joining member, the electrode of the detection piezoelectric bimorph element and the signal line can be easily electrically coupled, and an inexpensive angular velocity sensor can be supplied. Can be done, and the effect is great.

[Brief description of drawings]

FIG. 1 is a perspective view of an angular velocity sensor in one embodiment of the present invention, and FIGS. 2 and 3 are perspective views of a conventional angular velocity sensor. 1 ... Piezoelectric bimorph element for detection, 3 ... conductor, 4 ...
... Bimorph element for driving, 5a, 5c ... Signal line, 5b
... Drive electrodes

Claims (1)

[Claims] 1. A driving piezoelectric bimorph element and a detecting piezoelectric bimorph element, and an electrode composed of two signal lines having substantially equal areas on the driving piezoelectric bimorph element.
An angular velocity sensor, wherein the electrode is used as a signal line of the detection piezoelectric element.