JPS5837563A - Gas rate sensor - Google Patents

Abstract

PURPOSE:To reduce contact resistance and stabilize oscillation in a gas rate sensor for detecting angular speed basing on the deflection of gas flow by connecting and fixing respectively two appropriate positions of both the ends of thermo-sensitive device for detecting gas rate. CONSTITUTION:Ventilating holes 20a, 20b are penetrated into a discoid holder 20 and studs 22-25 are inserted and fixed into/on four concentrical ventilating holes 21a-21d respectively. Each stud is constituted by a tungsten member or the like having a nickel plated substrate and gold plated surface. Both end parts 26a, 26b of thermo-sensitive device 26, 27 made of gold-plated tungsten thin wire or the like are abutted upon the end surfaces 22a, 23a of respective studs and respective end parts are fixed and connected by bondings 30-33 respectively. The bondings 31, 33 are located at the innermost of the end surfaces of the studs. Consequently contact resistance between these thermo-sensitive device and studs is reduced and oscillation is stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a gas rate sensor that detects the angular velocity f:v of an object by deflection of a gas flow.

An angular velocity sensor, generally called a gas rate sensor, has a nozzle inside a sealed casing that ejects a gas flow toward the temperature sensing element of the flow sensor, and the gas flow is controlled by the influence of the angular velocity applied from the outside to the gas rate sensor. The magnitude t of the angular velocity (rate) is detected from the change in the output value of the 70-sensor that occurs when the deflection occurs. The gas rate sensor in this paper is more sensitive to vibrations than a gyro compass, and is highly sensitive and has excellent compliance, so it is used for course adjustment and attitude control of ships and automobiles. .

As shown in FIG. 4, this gas rate sensor has a sensor main body 2 fitted into a casing 1, and the front and rear ends of the sensor main body 2 are sealed by end plates 3 and 4.

A nozzle piece 5 having a nozzle hole 5m and a rectifying hole 5b is formed at one end of the senna body 2, and the other end is fixed to the casing IK via a holder 6. The holder 7 is fitted into the sensor main body 2 near the holder 6, and a flow sensor 8 for detecting gas flow velocity is disposed in the holder 7 at a position facing the nozzle hole 5a. This flow sensor 8 is formed of a pair of temperature sensing elements 8a and 8b arranged at a predetermined interval. The temperature sensing element 8m is the second
As shown in the figure, end surfaces 81a and 82a of two studs 81 and 82 are inserted and fixed vertically into the holder 7 at a predetermined interval.
Both ends are brought into contact with each other, and these two are connected and fixed by bonding 84 and 85. The temperature sensor Bb41 is formed similarly to the temperature sensor 8a.

A pump chamber 9 is formed between the holder 6 and the end plate 3, and a piezo plate 10 in which an orifice Ion is bored is housed in the pump chamber 9. The piezo plate 10 is configured to vibrate due to the electric current supplied through the connection terminal 11'&, and is configured to compress the gas in the pump chamber 9 due to the pumping action of this vibration. A gas flow passage 12 is formed in the axial direction between the casing 1 and the sensor body 2, and one end of this gas flow passage 12 is connected to the pump chamber 9 through the flow passage 13 and the discharge hole 6m of the holder 6. The other end communicates with the nozzle hole 5a and the rectifying hole 5b via the flow path 14, respectively.

In this configuration, when the piezo plate 10 is energized and vibrates, the gas in the left side portion of the piezo plate 10 of the pump chamber 9 is compressed and flows through the orifice 10 of the piezo plate 10 and the discharge hole 6a' of the holder 6. It flows in the axial direction within the passage 12 and reaches the flow passage 14 . The gas in the flow path 14 flows into the inner flow from the nozzle hole 5m to the temperature sensing element sa,
It is ejected towards 8b. Next, the through hole 71 of the holder 7
and the piezo plate 10 of the pump chamber 9 via the exhaust chamber 16v
Due to the displacement to the right, it passes through the oriice 10m and returns to the left side portion of the piezo plate 10 of the pump chamber 9. Here, when an angular velocity is applied to the gas rate sensor from the outside, the gas flow is deflected within the inner flow path 15, and a slight difference occurs in the outputs of the two temperature sensing elements 8m and 8b. Due to this output deviation, m# gas rate sensor? Detect the angular velocity acting on the

As mentioned above, this type of gas rate sensor detects the angular velocity based on the slight difference in the heat radiation distribution of the gas that the temperature sensing element pair receives due to the gas flow, and in order to improve the detection accuracy, K is the mounting accuracy of the flow sensor 8. Electrical,
It is necessary to stabilize the temperature.

However, in the gas rate sensor, each stud of the flow sensor and the temperature sensing element are located at one location, and:
The connection between the two points is not sufficient, and the contact resistance between the two is large.In some cases, the vibrations received by the casing may be transmitted to the temperature sensing element, causing the temperature sensing element to It vibrates and becomes electrically and thermally unstable, which has the disadvantage that the detection n1 degree of the sensor decreases.

The present invention was made for the purpose of eliminating the above-mentioned conventional drawbacks, and by connecting each stud of a flow sensor and a temperature sensing element at at least two places, and connecting one place at the innermost position of the stud, both of them can be connected. This provides a gas rate center that is electrically and thermally stable.

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

An embodiment of the present invention is shown in FIGS. 3 and 4, in which a holder 20, like the holder 7, is a pace sensor of a flow sensor. It is a circular disk body for forming a hole, and has a through hole 20a in the center and a plurality of, for example, four through holes 20a at equal intervals on a concentric circle in the radial direction.
0b' is drilled.

Furthermore, four holes 211 to 21d are bored concentrically between these through holes 20a and 20b. and,
Studs 22 to 25 are inserted and fixed into these holes 21a to 211C. Each of these studs 22 to 251 is made of a tungsten member, for example, and is plated with nickel as a base plating and gold plated on the surface.

In addition, each stud 22 to 25 is connected to the board surface 20CK of the holder 20.
Further, the distances from the board surface 20C of the holder 20 to one end surface of each of the studs 22 to 25 are equal.

The temperature sensing element 26 is a heating wire, for example, made of a thin tungsten wire, and its surface is plated with gold like the stud. One end 26m is in contact with the end surface 22alC of the stud 22, and the other end 26b is in contact with the end surface 23a (FIG. 4) of the stud 23, and each of the studs 22 and 23 and the temperature sensing element 26 are each connected to a plurality of, for example, Bonding at 2 places 30, 31. ．． Connected by 32 and 33. For example, the diameter of the bonding connection is 30 mm.
A thin gold wire for bonding is inserted into a cylindrical jig having an orifice hole of about μ size, melted at the orifice hole, and eluted from the orifice hole to a predetermined joint location. One bonding 30.32 of each stud 22.23 is for fixing the temperature sensing element 26 to each of these studs 22.23, and may be placed at any suitable location, but preferably at the center of the stud. It is better to connect it at a position closer to the outside. The position of the other bonding 31.33 of each stud 22.23 is on the innermost side 22b, 23b of each of these opposing studs 22.23.
(Fig. 4) is set at the peripheral edge of the end face. In this way, the temperature sensing element 26 is connected and fixed to the studs 22 and 23. Similarly, the temperature sensing element 27 is connected and fixed to the stands 24 and 25.

A holder 20 having such a structure is installed in the sensor main body 2 instead of the holder 7 (FIG. 1). Each temperature sensing element 26 and 2
7 is bonded to the studs 22, 23, and 24.25 at two locations, and one location is located at the innermost end of the stud, so it is securely fixed to the stud, and the contact resistance between the two is extremely low. small. In addition, even if the temporary casing 1 vibrates, the temperature sensing elements 26 and 27 are all (
There is no vibration and the contact resistance does not fluctuate. Therefore, the temperature sensing elements 26 and 27 are electrical.

It is extremely stable in terms of temperature, which improves senna detection accuracy.

As explained above, according to the present invention, since the stud and the temperature sensing element can be reliably connected and fixed, the contact resistance between them is extremely small, and there is no fluctuation due to vibration force (no flow This has the excellent effect of making the senna extremely stable electrically and temperature-wise, and improving the detection precision WIL1.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of a gas rate sensor, Fig. 2 is a cross-sectional view of a flow sensor manufactured by Yomei used in the gas rate sensor of Fig. 1, and Fig. 3 is a cross-sectional view of a flow sensor used in the gas rate sensor according to the present invention. FIG. 4 is an end view showing one embodiment of the flow sensor, and FIG. 4 is a cross-sectional view taken along line A-A' in FIG. 1...Casing, 2...Senna body, 10...
Piezo slate, 20...Holder, 22-25...
Stud, 26, 27...Temperature sensor, 30-33.
··bonding. Applicant Honda Motor Co., Ltd. Agent Patent Attorney Toshihiko Watanabe Figure 1? ! , 2 Figure 3 and LA.

Claims (1)

[Claims] 1. Directed towards a flow sensor having a temperature sensing element disposed inside the sensor body from the nozzle hole of the sensor body housed in the casing and having both ends fixed to the base via studs respectively. Based on the deflection of the gas that occurs when the angular velocity acts on the gas flow ejected from the The above-mentioned studs are connected and fixed at at least two places, and at least one of them is fixed at the innermost position of the stud.V%
The characteristic gas rate senna. 2. The gas rate sensor according to claim 1, wherein the temperature sensing element and the stud are fixed by bonding.