JPS6116487A - Electric resistor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electric resistor used in a thermal gas flow fA measurement device, a heat exchanger, or the like.

(Prior Art) In a thermal gas flow rate measuring device that measures gas flow rate based on gas flow and accompanying heat transfer, conventionally,
An X-shaped or ■-shaped electrical resistor is inserted into the gas flow channel, but the gas flow is disturbed or the flow velocity changes, or the waste flow velocity differs between the center side and the wall side of the flow channel. Therefore, it is difficult to detect the gas temperature and to heat the gas with good reproducibility, which is a factor in reducing measurement accuracy.

On the other hand, as mentioned above, heat exchangers that heat gas in the flow path also have the disadvantage that heat exchange cannot be performed reproducibly because the flow of waste in the flow path is not uniform. .

(Objective of the Invention) The object of the present invention is to provide an electrical resistor that can eliminate the above-mentioned drawbacks very easily.

(Structure of the Invention) The electrical resistor according to the present invention for achieving the above object has the following features:
The present invention is characterized in that a large number of through-holes for dregs conduction are provided in a substrate placed across the dregs flow path, and a thin film of electrically resistive material is applied to at least one side of the substrate.

(Function) Thus, the flow velocity distribution of the waste in the flow path is regulated by the large number of through holes when the waste passes through the through holes.

(Effects of the Invention) Therefore, when measuring gas flow values, it is possible to detect a uniform waste temperature and to heat the source with good reproducibility, and it is possible to perform highly accurate flow measurement, or For heat exchangers, since the gas flow is uniform,
We have come to expect effects such as reproducible heat exchange.

(Example) Hereinafter, a practical 7+hi example of the present invention will be explained based on the drawings. Fig. 1 shows an electric resistor A according to the present invention, and a substrate 1 disposed in a state crossing a gas flow path B to be described later. A large number of through holes a for gas conduction are provided in the substrate 1, and an electrically resistive material C is attached to one side of the substrate 1.

In detail, a silicon crystal wafer made by thinly slicing a silicon ingot is used as a base &1, and small circular gas conduction holes a of the same size are formed in this substrate 1 by etching etc.
. . are formed in large numbers, and then, on one side of this substrate 1, oxidation method or plasma CVI) (chemical vapor
An insulating film made of an inorganic material such as silicon or the like is formed into a recessed chamber by a method (abbreviation for Deposition).

Prior to the formation of this insulating film, it is desirable to perform a polishing treatment on the surface of the substrate 1 on which the insulating film is to be formed.

In other words, in a silicon wafer formed by slicing a silicon ingot, a process-altered layer reaching a depth of 30 to 60 μm is formed on the sliced surface, and the slicing direction is rough. Even if a layer is formed, there is a risk that this layer will peel off, so the damaged layer should be subjected to mechanical polishing such as lapping or polishing, or chemical polishing using a chemical solution such as an alkali. Therefore, it is desirable to ensure the formation of the insulation 1ikb.

Next, an electrically resistive material film is formed at a predetermined location on the insulating film by sputtering or the like, and a photoresist is applied to the crotch. Then, a mask for curing the resistor pattern in the shape of threading through the through holes a is applied to the photoresist, and exposure and development are performed to form an etching pattern on the photoresist.

Then, the resistive material film is etched using an ion beam milling device or the like to form a resistor pattern having a predetermined shape. Next, the photoresist is removed by ion beam etching, a solvent, etc., thereby forming the electrically resistive material C in a predetermined pattern.

Note that d and d in the figure are bonding pads made of gold or the like, and are for connecting the lead wires 2, 2.

Next, a protective film e made of an inorganic material such as silicon oxide is formed except for the bonding pads d and d, and if necessary, the upper surface of the protective film e is polished by the same method as for the insulating film. This constitutes an electric resistor A.

Note that the substrate 1 may be replaced with ceramic, glass, or other metals such as stainless steel.

Application examples of the electrical resistor A having the above structure are shown in FIGS. 2 to 4.

What is shown in FIG. 2 is a so-called self-heating type gas flow rate measuring device 3, in which two heating electrical resistors Al and A2, in which electrical resistance material C is nichrome, are connected to a flow path. are provided in the gas flow path B at intervals in the direction, and
Both resistors A1. A2 is connected to a circuit C that generates heat, and when gas flows through the waste flow path B, the gas becomes
It is heated by the second-stream electric resistor A1, and the heat is given to the downstream electric resistor A2, and the temperature of the downstream electric resistor Az changes, and due to this temperature difference, both paper antibodies A
There is a difference in the electrical resistance values of I and A2, and therefore both paper antibodies A
1. When the bridge circuit for A2 collapses, a voltage corresponding to the gas mass flow rate is output to the terminals 4, 4, and the gas flow rate is measured based on this.

According to the above configuration, the gas flow velocity distribution is regulated by branching flow of the waste through the many through holes a, and highly accurate force flow rate measurement can be performed.

In addition, in FIG. 2, 5 in the figure represents a resistor At.

The bodies are connected while holding the M, and are made of metal such as stainless steel, ceramic, etc., and are connected by diffusion bonding or adhesion, or mechanically connected with bolts or the like with a packing seal interposed.

The one shown in FIG. 3 is a sludge flow rate measuring device 3 of the supplementary sleeve heating method, which includes one heating electrical resistor A3 in which the electrical resistance material C is nichrome, and the electrical resistance material C is nickel or nickel. Two heat-sensitive electrical resistors A4 made of metal with a large temperature coefficient such as platinum. As and the heat-sensitive electric resistor A4.
A5 is provided in the gas flow path B with an interval between the heat-sensitive electric resistors A4 and A5, and the heat-sensitive electric resistors A4. An electric circuit C, which allows almost no current to flow through A5 and allows current to flow through the heating electric resistor A3, is connected to the resistors A3, A4, and As.

When the gas is passed through the gas flow path B, the gas is heated by the heating electric resistor A3, and heat is imparted to the downstream heat-sensitive electric resistor A5, thereby causing both the heat-sensitive electric resistors to A difference occurs in the electrical resistance values of the bodies A4 and As, and like the self-heating method described above, a voltage corresponding to the mass flow rate of gas is output to the terminal 4.4, and based on this, the It can measure gas flow rate.

The 41st item is a heat exchanger 6, which is
6 serves as a waste flow path B to one heating electrical resistor whose electrical resistance material C is nichrome, and a through hole a...
Since the flow rate of the scum passing through the sludge becomes uniform, the scum can be heat exchanged with good reproducibility, and the heated gas can be evenly distributed and discharged.

Incidentally, the heat exchanger 6 may be constructed by manufacturing a plurality of the heating electric resistors A6 in parallel, and the resistors A6 may be used for both fiI of the substrate 1! The heat exchanger 6 may be constructed by providing a heating electrical resistance material C2C on one surface and providing this in the gas flow path B.

Alternatively, as schematically illustrated in FIG. 5, a Thomas type flow rate measuring device 3 may be configured.

That is, the electric resistance materials c and c for heating and heat sensitivity are placed on the substrate 1.
Heat-sensitive electrical resistors A are provided on one side and the other side, respectively.
This resistor A7 and a heat-sensitive electrical resistance material 8 having a heat-sensitive electrical resistance material C provided on one side thereof are connected to the heating heat-sensitive electrical resistor 1> on the downstream side of the heat-sensitive electrical resistor A8. 1.
＠, A7 are placed in the waste flow path B at a distance in the direction of the flow path, and a known electric circuit (not shown) in the Thomas method is connected to both paper antibodies A7. A8
A device that connects to an electrical circuit that allows current to flow through this electrical circuit, and
When the gas flows through the gas flow path B, the electric resistor 1 for heating and heating
□The body A7 dissipates thermal energy, and since the amount of heat absorption or heat dissipation of the gas is proportional to the weight of the gas, the heat dissipation area of the heating heat-sensitive electrical resistor A7 is It is possible to measure the waste flow h().

Note that any of the electrical resistors A1 to A8 may be arranged inverted in the direction of the flow path; for example, in the electrical resistor A1 not shown in FIG. 2, its electrical resistive material C
Although the electrical resistance material C is placed on the upstream side of the flow path with respect to the substrate 1, it is also possible to place the electrical resistance material C on the substrate 1 and positioned on the downstream side of the flow path. It is something.

In addition, although the gas-conducting through-hole a is made of circular cedar, the through-hole a may be made into a triangular or hexagonal shape, as partially shown in FIG. Although not shown, it can be changed to a rectangular or pentagonal shape, and regardless of the shape, it is preferable to form them with the same size.In this case, since the amount of gas passing through each through hole a becomes constant, Electrical resistance A2 material C for some through holes ai p1-
), it is also an MJ function to estimate the total amount of gas passing through based on the amount of force passing through some of the through holes a.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a broken perspective view of an electrical resistor, and FIGS. 2 to 5 show examples of application of the electrical resistor, and FIGS. The figures are a schematic plan view of the gas flow rate measuring device, and FIG. 4 is a schematic diagram of the heat exchanger. FIGS. 6(a) and 6(b) are partial explanatory diagrams showing another embodiment of the through hole for gas conduction. 01: Board, a: Through hole for gas conduction, C: Electricity Resistance material, B... gas flow path. Figure 1 1--One board a--- is 4 abuse penetration hole C---'1. Io base 1 B-・Gasu Raku Fig. 2 Fig. 311 Fig. 4 Fig. 5 Fig. 6 <o> , ni-1\

Claims (1)

[Claims] An electrical resistor comprising a substrate disposed across a gas flow path, provided with a large number of through holes for gas conduction, and an electrical resistance material attached to at least one side of the substrate.