JPH04110666A - Gas rate sensor - Google Patents

Abstract

PURPOSE:To enable characteristics of each sensor after assembly to be the same easily and yield to be improved by achieving a divided configuration of an electrode holder consisting of a first electrode holder part and a second electrode holder part. CONSTITUTION:Each sensor of electrode holder parts 5A and 5B is welded to an electrode previously and those with the same characteristics are combined at the electrode holder parts 5A and 5B with each welded sensor. Then, joints 5Aa and 5Bb of the electrode holder parts 5A and 5B are joined and are formed into one piece by an adhesive etc., thus enabling the electrode holder parts 5A and 5B to be formed in one piece and a circular plate electrode holder 5 to be formed. Therefore, after the electrode holder 5 is assembled, a constitution with a sensor having the same characteristics can be obtained, thus enabling a gas rate sensor with stable characteristics to be assembled easily without performing any adjustment.

Description

Detailed Description of the Invention: a. Industrial Application Field The present invention relates to a gas rate sensor, and in particular, the present invention relates to a gas rate sensor, and in particular, the electrode holder is configured with a pair of electrode holder parts, and the characteristics of each sensor are easily matched, thereby making it easier to assemble the sensor. This invention relates to a new improvement for simplifying the adjustment process of each sensor.

b. Prior Art There are various types of electrode holders for this type of gas rate sensor that have been used in the past, but a representative one is the one shown in Fig. 5 disclosed in VF Publication No. 1-167671. The following configurations can be mentioned.

That is, the electrode holder designated by the reference numeral 5 in FIG. 5 is an integrally constructed electrode holder having a disk-like overall shape, and at the center of this electrode holder 5 are four rod-shaped electrodes 6a and 6b. , 6c and 6d are implanted.

Among the electrodes 6a to 6d, between the electrodes 6a and 6b and between the electrodes 6a to 6d,
A pair of hot wires 7a and 7b are stretched between electrodes 7a and 6d, and four gas guide holes 5a and 5b are provided at the peripheral edge of the electrode holder 5.

5c and 5d are formed.

Therefore, the gas flow supplied from the nozzle hole of the nozzle body (not shown) is configured to uniformly hit each of the hot wires 7a and 7b, and the uneven flow of the gas flow at the time of angular velocity input is detected by each of the hot wires 7a and -7b. By doing this, the angular velocity was detected.

C1 Problems to be Solved by the Invention Since the electrode holder of the conventional gas rate sensor was constructed as described above, the following problems existed;

In other words, since the electrode holder of the conventional structure described above is integrally constructed, and a pair of hot wires are provided between the four implanted electrodes, the characteristics (temperature coefficient difference) of the pair of hot wires are , resistance value difference) was extremely difficult to equalize.

Normally, as a single hot wire before welding to each electrode, it is relatively easy to make the characteristics of each pair almost uniform and to have the characteristics of the pairs, but this hot wire is an extremely thin wire (with a diameter of (several microns),
When welding to electrodes, when we measure the characteristics between each electrode,
The welding conditions often vary greatly depending on the welding conditions, and after welding, it was necessary to select an electrode holder that satisfies the characteristics of each hot wire.

Therefore, the assembly yield of the gas rate sensor itself is low, which is the biggest bottleneck in cost reduction and mass production.

The present invention has been made to solve the above-mentioned problems, and in particular, by configuring the electrode holder as a pair of electrode holder parts and making it easier to match the characteristics of each sensor, a gas rate sensor with high yield can be achieved. The purpose is to provide

62 Means for Solving the Problems A gas rate sensor according to the present invention includes a gas pump provided in a casing, and a nozzle body provided in the casing and having a nozzle hole for guiding a gas flow from the gas pump. and an electrode holder having a plurality of electrodes having at least one pair of sensors for receiving the gas flow, the electrode holder comprising a first electrode holder part and a second electrode holder part. , each of the TL electrode holder parts has at least one sensor.
The electrode holder portions are connected in an image-like manner.

e Function In the gas rate sensor according to the present invention, since the electrode holder has a divided structure consisting of a first electrode holder part and a second electrode holder part, at least one electrode holder is provided between each electrode of each electrode holder part. By selecting sensors with the same characteristics, each sensor has the same characteristics (temperature coefficient difference, resistance value difference) even when welded between the electrodes.

Therefore, by integrally joining each electrode holder part, an electrode holder having a pair of sensors having the same characteristics can be easily constructed.

f. Embodiments Hereinafter, preferred embodiments of the gas rate sensor according to the present invention will be described in detail with reference to the drawings.

Note that the same or equivalent parts as in the conventional example will be described using the same reference numerals.

Figures 1 to 4 are for illustration purposes only, and Figure 1 is a sectional view showing the overall configuration;
FIG. 2 is a plan view showing the divided T and electrode holder, FIG. 3 is a plan view showing the electrode holder integrally joined, and FIG. 4 is a block diagram.

In the figure, a casing designated by reference numeral 1 is approximately cylindrical in shape and has both ends open. Each end of the casing 1 is connected to a pump holder 2.
and the relay terminal plate 3, respectively, and the casing 1
The inside is cut off from the outside.

This pump holder 2 is provided with a diaphragm 4a made of an electrostrictive ceramic disk, and the peripheral edge of the diaphragm 4a is integrally fixed to the pump holder 2, so that the gas pump 4 made of an electrostrictive oscillating pump can be operated. It is formed.

Further, an electrode holder 5 is arranged inside the casing 1 at a position spaced apart from the diaphragm 4a by a predetermined distance, and the electrode holder 5 is configured as shown in FIGS. 2 and 3. .

That is, this electrode holder 5 has an almost disk-like overall shape, and is composed of a first electrode holder section 5A and a second electrode holder section 5B each having an approximately semicircular disk shape. By joining the respective joint parts 5Aa and 5Ba of 5B to each other, a disc-shaped electrode holder 5 joined in the shape of a bar is formed.

Four gas guide holes 5a are provided at the peripheral edge of the electrode holder 5.
~5d are formed, and furthermore, four rod-shaped electrodes 6a are formed.
~6d or arranged symmetrically about the central axis.

Among the gas guide holes 5a to 5d, the gas guide hole 5a,
5c is a semicircular hole 5 formed in each electrode holder part 5A, 5B.
aA, 5cA, and gas guide hole 5b
, 5d are formed independently on each electrode holder 5A, 5B.

Among the electrodes 68 to 6d, a pair of electrodes 6a6b is provided in the first electrode holder portion 5A, and each electrode 6a, 6b is provided in the first electrode holder portion 5A.
A first sensor 7a made of hot wire is connected to the opening by welding, and each electrode 6c, 6d is provided in the second electrode holder part 5B, and each electrode 6c, 6
A second sensor 7b made of a hot wire or the like is connected between d and d by welding.

Furthermore, the relay terminal plate 3 in the casing 1
A nozzle plate 10 having a nozzle hole 8 and an auxiliary hole 9 is provided near the relay terminal plate 3 and the nozzle plate 10.
There is a dust plate 1 approximately halfway between them.
1 is provided.

A pump chamber 12 is formed between the vibration plate 4a of the gas pump 4 and the pump holder 2, and the gas such as gas sent out by the electrostrictive vibration pump 4 flows through each gas guide hole 5a to 5d, and is sent to the gas flow path 13 such as gas.

An IC is located outside the relay terminal plate 3 of the casing 1.
A signal processing circuit section 14 consisting of
It is connected to the relay terminal 15 of the relay terminal board 3 for taking out the output signal to the outside.

Further, the relay terminal plate 3 is provided with a lead pin 16, and this lead pin 16 is connected to an external terminal 18 provided on the external casing 17.

The external terminal 18 transmits the electric power required to operate the electrostrictive vibration pump 4 through the signal processing circuit section 14 and the lead pin 16, as well as to a plurality of leads arranged in the axial direction inside the casing 1! It has the function of supplying it appropriately via i19.

Further, this external terminal 18 has the function of outputting the output signals of each sensor 7a, 7b after passing through the signal processing circuit section 14 to the outside.

The gas rate sensor according to the present invention is constructed as described above, and its operation will be described below.

First, before explaining its operation, the assembly of the electrode holder 5 will be described.

First electrode holder parts 5A and 5B shown in FIG. 2 are prepared, and each sensor 7a7b of each electrode holder part 5A and 5B is welded to the electrodes 6a to 6d in advance, and each welded sensor 7
Electrode holder parts 5A and 5B having the same characteristics are combined.

Next, each joint portion 5Aa, 5 of each electrode holder portion 5A, 5B
When Ba is joined and integrally joined with adhesive etc.,
The electrode holder parts 5A and 5B are integrated to form a disc-shaped electrode holder 5.

By integrally joining the two electrode holder parts 5A and 5B, the semicircular holes 5aA and 5cA can be integrally joined to form four gas guide holes 5a to 5d.

Therefore, by assembling the electrode holder 5 as described above, it is possible to obtain a configuration in which the sensors 7a and 7b have the same characteristics (temperature coefficient difference, resistance value difference) after the electrode holder 5 is assembled. Therefore, a gas rate sensor with stable characteristics can be easily assembled without any adjustment.

When the gas pump 4 is energized in the above-mentioned state, the diaphragm 4
a vibrates, the gas in the pump chamber 12 is compressed, and this compressed gas flows into the gas flow path 3 via the discharge port 4b of the moving plate 4a and the discharge port 5e of the electrode holder 5. The gas flow is guided into the space formed between the nozzle plate 0 and the dust plate 11, passes through the nozzle hole 8 and the auxiliary port 9, and flows through the air passage part 1b in the hollow cylindrical part 1a in the casing 1. It is ejected as IC towards each sensor 7a, 7b.

After the aforementioned compressed gas evenly hits each sensor 7a, 7b, it is discharged toward the diaphragm 4a through the main internal holes 5a to 5d, and this discharged gas is again converted into a gas flow B13 by the action of the gas pump 4. The liquid then returns to the nozzle body 10 and circulates within the casing 1 in the direction of the arrow.

In the above-described shape, when no angular velocity is applied to the casing 1, the gas flow hits each sensor 7a, 7b uniformly, but when an angular velocity is applied from the outside,
This gas flow is deviated within the casing 1, creating a non-uniform state between the sensors 7a and 7b, and by detecting a slight voltage difference, the angular velocity can be detected.

Although the above-mentioned gas is based on the case where a gas is used, it is also possible to use a gas other than gas rI.

g. Effects of the Invention Since the gas rate sensor according to the present invention is configured as above, the following effects can be obtained.

In other words, since the electrode holder has a divided structure consisting of a first electrode holder part and a second electrode holder part, it is possible to combine sensors in which at least one sensor provided between each electrode of each electrode holder part has the same characteristics. It can be used as
The characteristics of each sensor after assembly can be easily made the same, and the yield can be greatly improved.

[Brief explanation of drawings]

1 to 4 are for showing the gas rate sensor according to the present invention, and FIG. 1 is a sectional view showing the overall configuration;
Fig. 2 is a plan view showing a dissected electrode holder, Fig. 3 is a plan view showing an electrode holder joined together, Fig. 4 is a block diagram, and Fig. 5111 is a plan view showing a conventional electrode holder. It is. 1 is a casing, ]C is a gas flow, 4 is a gas pump, 5 is an electrode holder, 5A is a first electrode holder part, 5B is a second electrode holder part, 6a to 6d are electrodes, and 7a and 7b are sensors.

Claims (1)

[Claims] (1) Gas pump (4) installed inside the casing (1)
), a nozzle body (10) provided in the casing (1) and having a nozzle hole (8) for guiding the gas flow (1c) from the gas pump (4);
c) at least one pair of sensors (7a, 7
b), wherein the electrode holder (5) includes a first electrode holder part (5A) and a second electrode holder part. (5B), and each electrode holder part (5A, 5B) has the sensor (7a, 7b).
A gas rate sensor characterized in that at least one electrode holder part (5A, 5B) is provided and each of the electrode holder parts (5A, 5B) is integrally joined.