JPH03214019A - Angular-velocity sensor - Google Patents

Abstract

PURPOSE:To prevent the deterioration of characteristics by providing a preliminarily soldered part for silver electrodes on a driving piezoelectric element, performing wiring for soldering lead wires to the preliminary solder part, thereby quickly soldering the lead wires. CONSTITUTION:A silver electrode 2 for driving an element 1 and silver electrodes as lead patterns 3a and 3b to a detecting piezoelectric element are formed on a driving piezoelectric element 1. A preliminarily soldered preliminary solder part 4 is provided for parts of the silver electrodes. Lead wires 5a - 5c which are connected to lead pins 6a - 6c used as outer terminals are soldered to the preliminary solder part. Soldering of the lead wires 5a - 5c to the silver electrode 2 and the lead patterns 3a and 3b is performed at the preliminary solder part 4. Therefore, the soldering can be quickly performed readily and securely regardless of skill. Therefore temperature rise due to long application of a soldering iron on the silver electrodes is avoided, and the polarization of the element 1 is not broken.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a gyroscope, and particularly to an angular velocity sensor using vibration of a piezoelectric element.

2. Description of the Related Art Conventionally, a mechanical rotary gyro has been mainly used as an inertial navigation device using a gyroscope as a means of determining the direction of a moving object such as an airplane or a ship.

Although this method can provide stable orientation, since it is mechanical, the device is large-scale and costly, and it is difficult to apply it to equipment that is desired to be miniaturized.

On the other hand, there is a vibration-type angular velocity sensor that vibrates an object without using rotational force and detects the "Coriolis force" from the vibrated sensing element. Many of these structures employ piezoelectric and electromagnetic mechanisms.

In these cases, the mass that makes up the gyro does not move at a constant speed, but instead vibrates. Therefore, when an angular velocity is applied, the Coriolis force occurs as a vibration torque with a frequency equal to the frequency of the mass. The principle of a vibration-type angular velocity sensor is to measure angular velocity by detecting vibrations caused by this torque, and in particular, many sensors using piezoelectric materials have been devised. (Journal of the Japan Society for Aeronautics and Astronautics, Vol. 23, No. 267, Pages 339-350) Based on the above principle, an angular velocity sensor was invented in a prior patent application (Japanese Patent Application No. 126206/1983), and its structure is shown in Figure 2. show. As shown in FIG.
2, the driving piezoelectric elements 23 and the driving piezoelectric elements 23 are stacked and connected so that their vibration directions are perpendicular to each other, a driving electrode 26 is formed on the driving piezoelectric elements 23, and the two sets of assembly members are connected by an elastic coupling member 26.

With this structure, a lead pattern 24& is connected to the drive piezoelectric element 23 via the lead wire 27 from the support bin 29 installed on the base 3o.

The sensing piezoelectric element 2 is electrically connected to the conductive base 31 & 31b by the signal line formed by the conductive base 24b.
It is connected to No. 1 Dentaku.

The related operations of each component of the conventional angular velocity unit configured as described above will be explained. First, in order to drive a pair of driving piezoelectric elements 23 connected by an elastic coupling member 26, an alternating current signal is applied between the opposing surfaces as a common electrode and the driving electrodes 25 on the outer surfaces. The driving piezoelectric element 23 to which the signal is applied starts to vibrate symmetrically about the elastic coupling member 2e, which is what is called a tuning fork vibration.

The detection piezoelectric element 21, which is mechanically joined to the driving piezoelectric element 23 vibrating in this manner by the joining member 22, also vibrates. Therefore, when a rotation with an angular velocity ω is applied to the detection piezoelectric element 21 which is vibrating at the velocity ma, a "Coriolis force" is generated in the detection piezoelectric element 21jC. This "Coriolis force" is perpendicular to the speed f and has a magnitude of 2 mm.

(Here, m represents the equivalent mass of the tip of the detection piezoelectric element) Since the tuning fork is vibrating, if one of the detection piezoelectric elements 21 is vibrating at a speed of m at a certain point, the other detection piezoelectric element 21 is vibrating at a speed of m. The piezoelectric element 21 vibrates at a speed of -ma, and the "Coriolis force" is -2! I am ω. A pair of detection piezoelectric elements 2
1, "Coriolis force" in opposite directions acts, deforms in opposite directions, and charges are generated on the surface of the element due to piezoelectric effect 〇 A pair of sensor elements is affected by "Coriolis force"
The wires are connected so that the charges generated by the two are added together.

Therefore, even if a translational motion other than angular velocity is applied to this sensor, charges of the same polarity are generated on the surfaces of the pair of detection piezoelectric elements 21, so that they cancel each other out and no output is produced.

Here, Ma is the speed caused by vibration of the tuning fork, and if the tuning fork vibration speed is V = Malo・sinωot vo: Tuning fork vibration velocity amplitude ω0: Angular period of tuning fork vibration, the "Coriolis force" is Fc = 2m* 1 'O# 0m ginωoi, which is proportional to the angular velocity ω and the tuning fork imaging speed ma0, and becomes a force that deforms the detection piezoelectric element 21 in the plane direction.

Therefore, the surface charge Qc of the detection piezoelectric element 210 becomes QOocmaOIIω-5inωot, and if the tuning fork vibration velocity amplitude Ma0 is controlled to be constant, it becomes QOocω-sinωat, and the surface charge generated on the detection piezoelectric element 21 becomes QOocω-sinωat. The quantity Q is obtained as an output proportional to the angular velocity ω, and this signal is
If synchronous detection is performed with , a DC signal proportional to the angular velocity ω can be obtained.

Further, charges are generated in a pair of opposing driving electrodes 26 (one electrode is not shown) on the driving piezoelectric element 23 in accordance with the deformation of the driving piezoelectric element 23, but Since the electrodes 25 are symmetrical in shape and have the same area, the generated charges are equal, so the generated charges are canceled by signal processing using differential input.

Problem to be Solved by the Invention However, in the conventional angular velocity sensor, the lead wire 27 connecting the driving piezoelectric element 23 and the lead bin 28 is connected to the silver electrodes 24&, 24b of the driving piezoelectric element 23.

In order to solder on the 26th surface, it is necessary to properly heat the piezoelectric element 23 and connect it quickly so that the polarization of the piezoelectric element 23 is not removed due to the temperature rise caused by heating the solder. , there was a problem that required applying a soldering iron for a long time. In addition, since the lead wire 27 is as thin as φ01 mm, it is extremely difficult to process it quickly in the lead wiring process.
Another problem was that soldering tends to take a long time.

The present invention has been made in consideration of such problems, and an object of the present invention is to provide an angular velocity sensor in which lead wires can be soldered quickly and whose characteristics do not deteriorate.

Means for Solving the Problems In order to achieve the above object, the angular velocity sensor of the present invention has the following features:
In an angular velocity sensor in which two sensor orthogonal elements are assembled in a tuning fork shape, in which a drive piezoelectric element and a detection piezoelectric element are orthogonally connected to each other via a joining member, the silver electrodes on the drive piezoelectric element are preliminarily soldered. The angular velocity sensor of the present invention having this structure has a preliminary solder section on the electrode, and the connection using the lead wire is soldered to the preliminary solder section. Since soldering is easy, it is possible to quickly solder the lead wire connecting the drive piezoelectric element and the lead pin to the preliminary solder part on the silver electrode surface of the drive piezoelectric element. There is no possibility that the polarization of the piezoelectric element will be removed by heating. In addition, it is possible to provide an extremely high-performance angular velocity sensor that can be properly heated and quickly connected, and has good workability even with thin lead wires.

EXAMPLES Hereinafter, examples of the angular velocity sensor of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a soldering portion of an angular velocity sensor in an embodiment of the present invention.

Note that the overall configuration of the angular velocity sensor is the same as that of the conventional example shown in FIG.

As shown in FIG. 1, on the drive piezoelectric element 1, lead patterns 3a and sb to the drive silver electrode 2 of the drive piezoelectric element 1 and the detection piezoelectric element (not shown) are formed. There is. Among them, the shaded portion is a preliminary solder portion 4 coated with solder in advance. Lead wire csa, sb
, esc is the preliminary solder part 4 and lead pin 61L, eb
, 5c. Note that 7 is an elastic joining member.

The related operations of the angular velocity sensor of this embodiment configured as described above will be explained below.

The principle of angular velocity detection is the same as the conventional example, so a description thereof will be omitted.

On the surface of the drive piezoelectric element 1, silver electrodes 2 for driving the drive piezoelectric element 1 and lead patterns 31L and 3b for the detection piezoelectric element (not shown) are formed. Both require electrical connection to the external terminal of the angular velocity sensor.

There is a preliminary solder part 4 on a part of this silver electrode, which is used as an external terminal.
b, ecK connected lead wire S&.

Solder sb and sc.

Soldering of the lead wires sa, 6b, and sc to the silver electrodes 2 and lead patterns 3a, 3b is performed in the preliminary solder portion 4. Therefore, soldering is easy and depends on the skill level of the operator. Since it can be done reliably and quickly regardless of the problem, there is no need to worry about the temperature rise that occurs when the soldering iron is attached to the silver electrode for a long time due to poor workability, and there is no possibility that the polarization of the driving piezoelectric element 1 will be broken.

In this way, workability is improved and an angular velocity sensor with stable performance can be realized.

By performing solder plating on the preliminary solder portion 4, an angular velocity sensor with high performance and good workability can be obtained without being exposed to high temperatures.

Effects of the Invention As is clear from the above description, the present invention provides an angular velocity sensor in which two sensor orthogonal elements are assembled in a tuning fork shape, in which a drive piezoelectric element and a detection piezoelectric element are orthogonally connected to each other via a joining member. In this case, soldering is facilitated by providing a preliminary solder portion which is preliminarily soldered to the silver electrode on the drive piezoelectric element, and by soldering the lead wire to this preliminary solder portion. Therefore, the lead wire connecting the drive piezoelectric element and the lead pin can be soldered quickly onto the silver electrode surface of the drive piezoelectric element, regardless of the skill level of the operator. The polarization of the piezoelectric element will not be removed by heating.3 In other words, it can be heated appropriately and connected quickly, and has extremely high performance.
An angular velocity sensor with good workability can be provided.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a soldering portion of an angular velocity sensor according to an embodiment of the present invention, and FIG. 2 is a perspective view of a conventional angular velocity sensor. 1... Drive piezoelectric element, 2... Drive silver electrode of drive piezoelectric element, 31L, sb... Lead pattern, 4... Preliminary solder part ,5a,s
b, 5c...Lead wire, 6IL, eib,
60... Lead bin, 7... Elastic bonding member.

Claims (2)

[Claims] (1) A driving piezoelectric element, a sensing piezoelectric element, a joining member that joins the driving piezoelectric element and the sensing piezoelectric element, and an elastic joint that joins a pair of the joined elements to form a tuning fork structure. a support rod that fixedly supports the tuning fork structure on a base, and an electrical wiring electrode configured on the drive piezoelectric element, and vibrates the drive piezoelectric element and the detection piezoelectric element. They are stacked and joined using the joining member so that their directions are perpendicular to each other, a pair of joined elements are joined using the elastic joining member to form a tuning fork structure, and the tuning fork structure is fixedly held on the base by a support rod, and An angular velocity sensor in which an electrical wiring electrode is provided with a preliminary solder part, and an electrical wiring lead wire is soldered to the preliminary solder part. (2) The angular velocity sensor according to claim 1, wherein the preliminary solder is solder plating.