JPH06241847A - Fluidic flowmeter - Google Patents

Abstract

PURPOSE:To provide a fluidic flowmeter which can perform a wiring operation easily even in a narrow space, does not require a wiring space, can reduce the depth size of a case and can be made thin. CONSTITUTION:In a fluidic flowmeter, a flow-passage body 15 constituting a flow passage 26 is formed at the inside of a case with a built-in electronic circuit 19, a fluidic element 17 is installed inside the flow-passage body 15, and a flow sensor which measures a fine-flow-rate region and a piezoelectric film sensor which measures a large-flow-rate region are installed in the fluidic element 17. In the fluidic flowmeter, terminal pins 46, 48, 49 are installed respectively in the electronic circuit 19, the flow sensor and the piezoelectric film sensor, pin holes which are inserted into, and connected to, the terminal pins 46, 48, 49 are made in both end parts of a flexible printed-wiring board 51, and the electronic circuit 19 is connected electrically to the flow sensor and the piezoelectric film sensor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluidic flow meter which detects an alternating pressure wave generated by an oscillating phenomenon of a fluid such as a gas ejected from an ejection nozzle into a flow passage to detect a flow rate.

[0002]

2. Description of the Related Art A fluidic flow meter for measuring the flow rate of gas, which is installed in a general household or the like, is disclosed in, for example, Japanese Patent Laid-Open No. 63-63.
It is known from JP-A-313018 and JP-A-1-250725.

The fluidic flowmeter has a jet nozzle provided on the inlet side of the flow passage. When a fluid is jetted from this jet nozzle into the flow passage, the jetted fluid flows along the side wall on the right side, for example, due to the Coanda effect. A part of the fluid that has flowed to the right side wall becomes the return fluid, the fluid energy of this return fluid is imparted to the ejected fluid, and the ejected fluid flows along the left side wall, which in turn flows to the left side wall. A part of the discharged fluid becomes a return fluid, the fluid energy of the return fluid is applied to the jet fluid, and the jet fluid again flows along the right side wall.

That is, an alternating pressure wave is generated by the vibration phenomenon of the fluid ejected from the ejection nozzle into the flow path. This alternating pressure wave is detected by the piezoelectric film sensor, the flow rate is calculated from this frequency, and the flow rate of the fluid is detected.

6 and 7 show a conventional fluidic flow meter, and 11 is a case. The case 11 is composed of a rectangular box-shaped case body 12 and a lid 13 that closes an opening of the case body 12.

At the bottom of the case body 12, the gas inlet body 1 is provided.
4 and the gas outlet body 15 are arranged side by side, and a display window 16 is provided on the upper part.
Is provided. A fluidic element 17 and a shutoff valve 18 are installed in the lower part inside the case 11,
An electronic circuit 19, a pressure switch 20, and an integrated display substrate 22 facing the display window 16 are installed on the upper portion.

The fluidic element 17 will be described. Reference numeral 23 is a flow path body formed by die casting or the like, and the opening of the flow path body 23 is packed 2
The flow path 26 is formed by closing the cover body 13 via the lid 4.

The gas inlet port 14 is located upstream of the flow path 26.
, And the downstream side communicates with the gas outlet body 15 via the fluidic element 17. A valve seat 27 is provided in the middle of the flow path 26, and the valve body 28 of the shutoff valve 18 faces the valve seat 27. That is, the pressure switch 2
0 detects an abnormality, the shut-off valve 18 causes the flow path 26
It is configured to be able to shut off.

The shutoff valve 18 will be described below.
Is a base, and the base 30 has a pair of rods 31
A self-holding solenoid 32 is supported on these rods 31 so as to be movable back and forth with respect to the valve seat 27. That is, the rod 3 is provided on both sides of the solenoid 32.
A support piece 33 that fits in 1 is provided in a protruding manner, and the support piece 33 is urged by a coil spring 34 that is fitted in the rod 31 in a direction of retracting from the valve seat 27.

The valve body 28 is provided on the plunger 35 of the solenoid 32, and a coil spring 36 for urging the valve body 28 toward the valve seat 27 is provided between the valve body 28 and the base 30. .

When the coil of the solenoid 32 is in a non-energized state, the plunger 35 overcomes the coil spring 36 and is attracted to the magnet, and the valve element 28 is separated from the valve seat 27 and is in the valve open state. When a reverse magnetic field is applied by energizing the valve body 28, the restoring force of the coil spring 36 presses the valve body 28 against the valve seat 27 to maintain the valve closed state.

Further, a return button 37 as a return operation portion is provided on the side wall of the case body 12 facing the back surface of the solenoid 32, and the return button 37 is provided on the return button 37.
A return shaft 38 that comes into contact with the rear surface of 2 is connected, and a coil spring 39 that biases the return shaft 38 in the backward direction is provided on the return shaft 38.

The electronic circuit 19 and the solenoid 32 are also provided.
Are electrically connected by a lead wire 40, and the electronic circuit 19 is provided in the fluidic element 17 and a flow sensor 41 for measuring a minute flow rate region and a piezoelectric film for measuring a large flow rate region. The sensor 42 is also electrically connected by the lead wire 40.

[0014]

By the way, the fluidic flowmeter configured as described above includes the electronic circuit 19, the shutoff valve 18, the electronic circuit 19, the flow sensor 41, the piezoelectric film sensor 42, and the pressure sensor 20. It is electrically connected by a lead wire 40. Therefore, a space for wiring is required inside the case 11, and the case 11 is accordingly increased in size, and wiring work is performed in a narrow space.
Workability is poor.

The present invention has been made in view of the above circumstances, and the purpose thereof is to easily perform wiring even in a narrow space without causing interference with peripheral parts.
An object of the present invention is to provide a highly reliable fluidic flowmeter that does not have a risk of damaging peripheral parts or disconnection.

[0016]

In order to achieve the above-mentioned object, the present invention provides a case containing an electronic circuit, a flow path main body which is provided inside the case and constitutes a flow path, and this flow path. A fluidic flowmeter consisting of a fluidic element incorporated in the channel body, a flow sensor provided in the fluidic element for measuring a minute flow rate range, and a piezoelectric film sensor for measuring a large flow rate range. In, while providing a terminal pin to each of the electronic circuit and the flow sensor and the piezoelectric film sensor,
The flexible printed wiring board is provided with pin holes inserted into and connected to the terminal pins at both ends thereof to electrically connect the electronic circuit to the flow sensor and the piezoelectric film sensor.

Pin holes provided at both ends of the flexible printed wiring board are electrically connected to each other by inserting and connecting terminal pins provided on the electronic circuit, the flow sensor and the piezoelectric film sensor, respectively, in a narrow space. Even if there is, wiring can be done easily.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIGS. 1 to 5, the electronic circuit 19 installed inside the case 11 has its circuit board 45 facing the front surface of the case body 12, and a large number of terminal pins are provided on this end surface. 46 are projected in a line.

A plurality of terminal pins 47 are projectingly provided on the side surface of the solenoid 32 of the shutoff valve 18 which faces the front surface of the case body 12. In addition, a plurality of terminal pins 48 and 49 are provided on the side surfaces of the flow sensor 41 and the piezoelectric film sensor 42 provided on the fluidic element 17 so as to face the front surface of the case body 12.

That is, the electronic circuit 19 and the solenoid 3
2. The flow sensor 41 and the piezoelectric film sensor 42 are provided with terminal pins 46 to 49 aligned in the same direction. Wiring can be made on the front side of the case body 12.

The terminal pin 46 of the electronic circuit 19 and the terminal pin 47 of the solenoid 32 are electrically connected by a first flexible printed wiring board (hereinafter referred to as a first FPC) 50. In addition, the terminal pin 46 of the electronic circuit 19, the flow sensor 41, and the piezoelectric film sensor 42.
The terminal pins 48 and 49 are electrically connected by a second flexible printed wiring board (hereinafter referred to as a second FPC) 51.

In the first FPC 50, a conductive film 53 is printed on a strip-shaped flexible film 52 made of an insulating material, and pin holes formed in the conductive film 53 at both ends of the flexible film 52. 54 is provided. Further, a flexible portion 55 having a cutout portion 52a is provided in the middle of the flexible film 52. In addition, an insulating reinforcing plate 56 made of a thin plate is adhered to both ends and a middle portion of the flexible film 52, and the flexible film 52 is partially reinforced to strengthen the waist, and the flexible film 52 is first reinforced by a hand such as an automatic mounting machine. FPC5
It is possible to hold 0.

The pin hole 54 on the one end side of the first FPC 50 is inserted into the terminal pin 46 of the electronic circuit 19, and the pin hole 54 on the other end side is inserted into the terminal pin 47 of the solenoid 32. , 47 are connected to the conductive film 53 by soldering or the like.

The second FPC 51 is also basically the first
The FPC 50 has the same structure as that of the FPC 50, and a conductive film 53 is printed and printed on a strip-shaped flexible film 52 made of an insulating material. Pin holes 57 formed in the conductive film 53 at both ends of the flexible film 52. Is provided.

Further, an insulating reinforcing plate 56 made of a thin plate is adhered to both ends and a middle portion of the flexible film 52, and the flexible film 52 is partially reinforced to strengthen the waist, and a hand such as an automatic mounting machine is provided. This makes it possible to grip the second FPC 51.

The pin hole 57 on the one end side of the second FPC 51 is inserted into the terminal pin 48 of the electronic circuit 19 and the flow sensor 41, and the pin hole 54 on the other end side is inserted into the terminal pin 49 of the piezoelectric film sensor 42. This terminal pin 46,4
Reference numerals 8 and 49 are connected to the conductive film 53 by soldering or the like.

Further, the pressure switch 20 provided inside the case 11 has a pair of terminal pins 59 projectingly provided on the upper portion thereof, and the terminal pins 59 and the electronic circuit 19 form a third FPC.
It is electrically connected by 60. That is, the third
Of the FPC 60 is provided with pin holes 61, one of the pin holes 61 is inserted and connected to the terminal pin 46 of the electronic circuit 19, and the other of the pin holes 61 is formed by folding the third FPC 60 in two. Then, it is inserted and connected to the terminal pin 59 of the pressure switch 20.

According to the fluidic flowmeter having such a structure, the electronic circuit 19, the flow sensor 41 and the piezoelectric film sensor 42 are electrically connected by the second FPC 51. Electronic circuit 19 and flow sensor 41
Since the terminal pins 46 to 49 aligned in the same direction are provided on the piezoelectric film sensor 42 and the piezoelectric film sensor 42, respectively, the flow path main body 2
The second FPC 51 can be mounted from the front side of 3, and mounting by an automatic mounting machine becomes possible.

Further, terminal pins 46 to 49 projecting from the electronic circuit 19, the flow sensor 41 and the piezoelectric film sensor 42.
Is provided so as to project toward the front part, and the second FPC 51 is supplied from the front side, and the pin holes 57 provided at both ends are inserted into the terminal pins 46 to 49 and soldered, thereby making it easy. Can be electrically connected.

In addition, the second FPC 51 is the case body 1
Since it is arranged along the inner surface of the front surface of No. 2, no wiring space is required, and the depth dimension of the case main body 12 is small,
The case 11 can be made thinner.

[0032]

As described above, according to the present invention, the electronic circuit, the flow sensor, and the piezoelectric film sensor are provided with the terminal pins, and the flexible printed wiring board is inserted and connected at both ends thereof. A pin hole is provided to electrically connect the electronic circuit to the flow sensor and the piezoelectric film sensor.

Therefore, wiring can be easily performed even in a narrow space, and the flexible printed wiring board is arranged along the inner surface of the front surface of the case. Therefore, no wiring space is required, and the depth dimension of the case is small. The effect is that it can be made thinner.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view of a fluidic flow meter according to an embodiment of the present invention.

FIG. 2 is a vertical sectional side view of the fluidic flow meter according to the embodiment.

FIG. 3 is a cross-sectional plan view of the fluidic flow meter of the same embodiment.

FIG. 4 is a perspective view of a flexible printed wiring board according to the same embodiment.

5A and 5B are a front view and a side view showing an electrical connection structure between the electronic circuit and the pressure switch of the embodiment.

FIG. 6 is a vertical sectional front view of a conventional fluidic flow meter.

FIG. 7 is a vertical sectional side view of a conventional fluidic flow meter.

[Explanation of symbols]

17 ... Fluidic element, 19 ... Electronic circuit, 32 ... Solenoid, 46, 48, 49 ... Terminal pin, 51 ... Second FPC, 57 ... Pin hole.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Naoshi Isshiki 1-3-2 Shimura, Itabashi-ku, Tokyo Inside Kinmon Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A case having a built-in electronic circuit, a flow path body provided inside the case to configure a flow path, a fluidic element incorporated in the flow path body, and a fluidic element provided in the fluidic element. In a fluidic flowmeter comprising a flow sensor for measuring a minute flow rate region and a piezoelectric film sensor for measuring a large flow rate region, a terminal pin is provided for each of the electronic circuit, the flow sensor and the piezoelectric film sensor. And a pin hole inserted into and connected to the terminal pin at both ends of the flexible printed wiring board to electrically connect the electronic circuit to the flow sensor and the piezoelectric film sensor. .