JPH0329859A - Gas type angular velocity detector - Google Patents

Abstract

PURPOSE:To detect the temp. change of gas at proper temp. by forming a gas passage and a bridge part to a semiconductor substrate by etching and providing a gas temp. detecting resistor composed of a metal having high resistance temp. coefficient to the bridge part. CONSTITUTION:Semicircles and half grooves are respectively formed to lower and upper semiconductor substrates 1, 2 by etching and both substrates are superposed one upon another to form a nozzle orifice 3 and a gas passage 4. The bridge part 5 stretched across the gas passage 4 is formed to the substrate 1 by etching and a gas temp. detecting resistor 6 composed of a metal material having high resistance temp. coefficient is provided to the bridge part 5. The bridge part 5 is provided on the upstream side of the passage 4 in the vicinity of a pair of the heat wires 71, 72 symmetrically provided on both sides of the center line of the passage 4. By applying voltage to the resistor 6, the temp. of the gas in the vicinity of the heat wires 71, 72 can be detected from the change of the resistance value of said resistor 6 without disturbing the gas flow in the passage 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas type angular velocity detector that detects angular velocity acting on a detector body.

In general, a gas type angular velocity detector, as shown in Fig. 5,
Inside the sealed casing 1l, a gas flow is ejected from the nozzle hole 12 into the gas passage 13 toward a pair of flow sensors l4, and as shown in FIG. When the flow deviates from the center line 〇1〇 and is deflected to one side, the difference in temperature sensing output that occurs between the pair of heat wires 141 and 142 made of tungsten or the like with a large resistance temperature coefficient in the flow sensor 14 is extracted. Then, the direction and magnitude of the angular velocity ω acting on the detector body at that time are detected.

The pair of heat wires 141 and 142 are arranged symmetrically with respect to the center line 〇10〇 of the nozzle hole 12 and the gas passage 13, and the lateral angular velocity ω is applied to the detector body. When no action is taking place, the gas ejected from the nozzle hole l2 flows straight along its center line ○-○ and evenly hits each heat wire 14], 142, and each heat wire 141. ．． The amount of heat dissipated to 142 is made equal.

Therefore, if such a gas type angular velocity detector is mounted on a moving object, it becomes possible to determine the amount of change in the moving direction of the moving object.

In FIG. 5, reference numeral 15 indicates a diaphragm type pump, and its pump I5 sends the gas contained in the casing 11 through the flow path 16 to the nozzle hole 12.
Gas is constantly circulated within the casing I1. I7 is a rectifying hole that rectifies the gas flow jetted into the gas passage 13 from the nozzle hole (2).

However, in such a gas type angular velocity detector, the pair of heater wires 141 and 142 are
It is difficult to prepare resistors with exactly the same resistance-temperature characteristics, and if there are differences in the resistance-temperature characteristics, even at zero rate when no angular velocity ω is acting on the detector body, the temperature at that time will change. correspondingly each heat wire 14]. , 142 causes an output to be generated in the detector.

Therefore, it is necessary to offset the output of the detector at zero rate 1・hour by −3−4 from the detected output of the actual angular velocity ω, but since the output at zero rate will fluctuate if the gas temperature changes. The gas temperature in the gas type angular velocity detector is detected by a temperature sensor, and the offset 1 value corresponding to the detected temperature is predicted by a computer.

Conventionally, when installing a temperature sensor in a gas-type angular velocity detector, installing it in the gas passage near the pair of heat wires would disturb the gas flow and complicate the structure of that part. Therefore, the temperature sensor is installed outside the gas passage away from the pair of heat wires, but it is not possible to accurately detect the gas temperature at the pair of heat wires.

Conventionally, a high-sensitivity, high-performance thermistor is used as a temperature sensor, but compared to a heat wire pair, there is a difference in sensitivity and performance when sensing temperature, and the gas temperature applied to the heat wire pair is different. It cannot be said that the accuracy is necessarily sufficient to detect changes in .

Furthermore, conventionally, the heater 1-wire 14 provided in a pair
When offset the output generated from the difference in the temperature characteristics of the + and 142 resistances, the offset value will fluctuate if the gas temperature inside the detector changes due to the external temperature. The main body of the detector is installed in a constant temperature bath.

However, according to this method, the entire detector is maintained at a constant temperature, resulting in a large constant temperature bath, and the gas inside the detector is heated from the outside, so it takes time to control the gas temperature.

．． The present invention has been made in consideration of the above points, and it detects the gas temperature near the heat wire pair on the gas passage without disturbing the gas flow, and also detects the gas temperature in the vicinity of the heat wire pair on the gas passage. The object of the present invention is to provide a gas type angular velocity detector equipped with a gas temperature detection means that can accurately detect changes in gas temperature.

The present invention also provides a structurally superior gas type angular velocity detector that directly heats or cools the gas flowing through the gas passage.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the gas-type angular velocity ejector according to the present invention, as shown in FIGS. The nozzle hole 3 and the gas aisle 4
I try to be careful about this.

In this case, in particular, in the present invention, a bridge part 5 spanning the gas passage 4 is formed on the lower semiconductor substrate (2) forming the gas passage 4 by etching, and the bridge part 5 is filled with a gas made of a metal material having a large temperature coefficient of resistance. A temperature detection resistor 6 is provided.

The bridge portion 5 is provided on the upstream side of the gas passage 4 in the vicinity of the pair of heel wires 71 and 72 that are symmetrically provided on both sides of the center line ○○ of the gas passage 4.

The gas temperature detection resistor 6 is made by depositing the same metal material of tungsten or platinum as the heat wires 71 and 72 on the surface of the bridge part 5, and then depositing the metal in the direction in which the bridge part is constructed. etched in a line shape,
1- Prominent by rimming.

Further, on the semiconductor substrate l on both end sides of the bridge portion 5, the same metal material as the gas temperature detection resistor 6 is vapor-deposited.
By etching and rimming it, an electrode portion 8 connected to the gas temperature detection resistor 6 is formed.

The heat 1-wires 71 and 72' are connected to the lower semiconductor substrate.
Bridge part 9 shaped by etching
A metal with a high temperature coefficient of resistance, such as tungsten or platinum, is deposited on the surface of the metal, and then etched.
1- It is shaped with a predetermined pattern by rimming.

7 8 At that time, each heating wire 71. is connected in a pattern such that the total length is long so that the deflection of the gas flow can be detected with sufficient sensitivity with sufficient length. , 72 are formed.

The bridge portion 5 and the bridge portion 9 are shaped so that they are at the same height.

Furthermore, the same metal material as the heat wires 71.72 is deposited on the semiconductor substrate 1 on both end sides of the bridge portion 9, etched, and rimmed to form each heat wire 71.72. The electrode parts ■0 connected to each other are shown.

With this configuration, by applying a constant voltage to the gas temperature detection resistor 6, the gas temperature can be electrically detected from a change in the resistance value.

At that time, in the present invention, a bridge portion 5 that crosses the gas passage 4 is provided.
Since the line-shaped gas temperature detection resistor 6 is provided above, the gas temperature near the heat wires 71 and 72 can be detected without disturbing the gas flow in the gas passage 4.

This is particularly true when the bridge section 5 on which the gas temperature detection resistor 6 is formed is provided so as to be at the same height as the bridge section 9 on which the heater wires 7 and 72 are formed. Because of this, even more effects can be obtained.

Further, the gas temperature detection resistor 6 is connected to the heat wire 71.
Since the heat wires 71 and 72 are made of the same metal material as the heat wires 71 and 72, they can detect temperature changes in the gas flow with the same level of sensitivity and accuracy as the heat wires 71 and 72, which determine the deflection of the gas flow by the difference in temperature sensing output. can.

Therefore, according to the present invention, the offset value of the detector output can be set with high precision in accordance with the detected gas temperature.

Furthermore, in the present invention, the lower semiconductor substrate 1-
I:. In addition, the gas flow heating element 18 and cooling element 19 are each integrally formed using semiconductor manufacturing technology.

As the heating element 18 and the cooling element 19 for the gas flow, for example, when a p-type semiconductor and an n-type semiconductor are joined via a metal plate electrode and a current is passed, heat generation or absorption occurs in the joint part. A Peltier element is used.

Alternatively, the heating element 18 may be formed by depositing a metal serving as a heater material on the lower semiconductor substrate 1 and then etching it in an appropriate pattern.

As described above, according to the present invention, using semiconductor manufacturing technology,
The heating element 18 and the cooling element 19 can be integrated and installed in the compact 1- on the semiconductor substrate 1 on which the gas passage 4 is formed relatively easily, without disturbing the gas flow in the gas passage 4. The heating element 18 and the cooling element 19 allow the gas flowing through the gas passage 4 to be directly heated or cooled.

Therefore, the detector main body can be made smaller, the gas temperature inside the detector can be better controlled, the gas temperature can be quickly raised to a certain level, and the gas temperature can be controlled by the gas temperature detection resistor 6. By appropriately driving the heating element 8 and the cooling element 19 while detecting the gas temperature, the responsiveness in keeping the gas temperature constant can be improved.

In this case, considering the resistance temperature characteristics of the pair of heat wires 71 and 72, it is preferable to maintain the ambient temperature at the time of starting energization to the heat wires 71 and 72 from the viewpoint of eliminating temperature drift 1. According to this method, the gas temperature can be immediately controlled so as to maintain the temperature at the time of rising and cooling.

In this case, it becomes possible to eliminate the time required to start up the gas type angular velocity detector into a usable state, and it becomes possible to perform angular velocity detection with high accuracy immediately after power is turned on.

In the present invention, the nozzle hole 3 and the gas passage 4 are formed by etching the semiconductor substrates 1 and 2 using semiconductor manufacturing technology, so the nozzle hole 3 and the gas passage 4 can be formed with high processing precision. It can be obtained with good mass production.

Therefore, by obtaining the nozzle hole 3 and the gas passage 4 with high processing accuracy, the gas flow that flows straight along the center line 〇1〇 of the gas passage 4 when no angular velocity acts on the detector body. is ejected from the nozzle hole 3, thereby effectively improving the detection accuracy of the gas type angular velocity detector.

Note that, if necessary, rectifying holes (see FIG. 5) for rectifying the gas flow ejected into the gas passage 4 are provided symmetrically on at least both sides of the nozzle hole 3, as described above. Needless to say, the rectifying holes can be formed by etching half holes in the lower semiconductor substrate 1 and the upper semiconductor substrate 2, respectively.

Even if this rectifying hole is provided, it can be machined uniformly and accurately.

Further, in the present invention, a pair of heat I
- Since the wires 71 and 72 are formed, each of the heat wires 71 and 72 can be precisely processed in a simultaneous process, and a pair of heat wires with almost no variation in composition, crystal structure, resistance temperature characteristics, etc. can be formed. 1 to wire 71
．． 72 can be easily obtained.

Further, according to the present invention, since the gas temperature detection resistor 6, the electrode section 8, the heat wire 7], 72, and the electrode section 10 can be integrally formed of the same metal, it is possible to connect them. It is no longer necessary to use gold bonding means, etc., and therefore a dissimilar metal such as gold is interposed to connect the gas temperature detection resistor 6 and the heater wire 7], 7.
This eliminates the possibility that the detection sensitivity of the gas temperature detection resistor 6 and the heat wires 71 and 72 will be affected by thermoelectromotive force due to different metals, which will cause a decrease in the detection accuracy.

Furthermore, according to the present invention, the nozzle hole 3 and the gas passage 4,
Gas temperature detection resistor 6, heating 1-wires 71, 72,
The main parts of the heating element 18 and the cooling element 19 can be precisely processed into a small size using semiconductor manufacturing technology, and an ultra-small gas type angular velocity detector can be realized.

As mentioned above in Toyotama, the gas type angular velocity detector according to the present invention is based on the deflection of the gas flow that occurs when angular velocity acts on the gas flow jetted into the gas passage from the nozzle hole toward the heat wire pair. In a gas-type angular velocity detector that generates an output corresponding to the difference in temperature-sensing output produced in a pair of heat wires, a gas passage and a bridge part over the gas passage are formed by etching the semiconductor substrate, and the A gas temperature detection resistor made of a metal material with a large resistance temperature coefficient is provided in the bridge part, and the gas temperature near the heat wire pair in the gas passage can be detected without disturbing the gas flow. This has the advantage that changes in gas temperature can be detected with appropriate accuracy depending on the heat wire pair.

Further, in the gas type angular velocity detector according to the present invention, a heating or cooling element for the gas flow is integrally formed on the semiconductor substrate in the gas passage by semiconductor manufacturing technology. By providing the element, the gas flowing through the gas passage can be directly heated or cooled without increasing the size of the detector, and the gas temperature inside the detector can be maintained constant with good controllability. have.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a nozzle hole and gas passage portion in a gas type angular velocity detector showing an example of the present invention; FIG. 2 is a plan view of a lower semiconductor substrate in the nozzle hole and gas passage portion; FIG. 3 is a partial perspective view of the lower semiconductor substrate, FIG. 4 is a sectional view taken along line A-A in FIG. 1, and FIG. 5 is a front sectional view showing a conventional gas type angular velocity detector. FIG. 6 is a diagram showing the deflection state of the gas flow when angular velocity is applied to the gas type angular velocity detector. 1. Lower semiconductor substrate 2. Upper semiconductor substrate 3. Nozzle hole 4. Gas passage 5, 9.. Bridge portion 6.
・Resistor for gas temperature detection 71.72... Heat wire 8, 10... Electrode section 18... Heating element 19...
・Cooling element 3 Figure 4 Figure 5 Figure 6 Figure 14/

Claims (1)

[Claims] 1. The deflection of the gas flow that occurs in the heat wire pair due to the deflection of the gas flow that occurs when angular velocity acts on the gas flow ejected from the nozzle hole toward the heat wire pair into the gas passage. In a gas type angular velocity detector that generates an output according to the difference in temperature-sensing output, the semiconductor substrate is etched to form a gas passage and a bridge part spanning the gas passage, and the bridge part is made of a metal material with a large temperature coefficient of resistance. 1. A gas type angular velocity detector, characterized in that it is provided with a resistor for gas temperature detection consisting of: 2. The gas type angular velocity detector according to item 1 above, wherein the metal material of the gas temperature detection resistor is the same as the heat wire material. 3. The first gas temperature detection resistor is formed by depositing a metal material having a large temperature coefficient of resistance on the bridge portion and then etching the metal in a line shape in the direction in which the bridge portion is constructed. Gas-type angular velocity detector as described in Section. 4. The difference in temperature-sensing output that occurs in the heat wire pair based on the deflection of the gas flow that occurs when angular velocity acts on the gas flow ejected from the nozzle hole toward the heat wire pair in the gas passage. In a gas type angular velocity detector that produces a corresponding output, a gas passage is formed by etching the semiconductor substrate, and a heating or cooling element for the gas flow is integrated on the semiconductor substrate in the gas passage using semiconductor manufacturing technology. A gas type angular velocity detector characterized by the following: