JPH01304319A - Flow rate detector - Google Patents

Abstract

PURPOSE:To perform highly reliable flow rate detection with a flow rate detector by providing a light emitting and light receiving elements in such a way that the optical axis between both elements can pass the circulating movement locus of a ball and wiring their lead sections on both sides of a volute case on one base plate. CONSTITUTION:When a fluid flows into a volute chamber 2, the fluid circulates inside the volute chamber 2 and a ball 5 moves along a circulating locus by rolling in an almost vertical direction while it is brought into contact with the inner wall of the chamber 2. By providing a light emitting and light receiving elements 9 and 8 on both sides of a volute case 1 so that the center of the optical axis between the elements 9 and 8 can pass the plane of the circulating movement locus of the ball 5, the difference in current flowing through the element when the light emitted from the element 9 is intercepted by the ball 5 and when the light is not intercepted by the ball 5 is converted into pulses by means of a control circuit and flow rate signals are obtained. As a result, the light interception and transmission can be clearly and accurately fetched as pulse signals even when the flow rate is large and highly reliable flow rate detection can be performed by inputting stable pulse signals to a microcomputer 30 without receiving any influences from noises and disturbing light.

Description

Detailed Description of the Invention 2.-7 Industrial Application Field The present invention relates to a ball rotation type flow rate detection device that detects the amount of fluid flowing in a flow path by rotation of a ball. Such a flow rate detector can be used, for example, to detect the instantaneous flow rate of liquid and control the flow rate in sanitary cleaning equipment, hot water supply equipment, and other equipment.

BACKGROUND OF THE INVENTION Conventionally, there have been two types of ball-rotating flow rate detection devices: a magnetic detection method and an optical detection method.

The magnetic detection method has the disadvantage that it is easily influenced by the magnetic field generated by the lead wires when there are lead wires or the like through which high current flows. At this point, the photodetection method (d
] It has the feature of not being affected by the surrounding magnetic field,
For example, in JP-A-57-74614, the following structure was used.

In FIGS. 6 and 7, reference numeral 13 denotes an annular flow path having a circular cross section, and an inflow passage 11 and an outflow passage 12 are opened at the outer periphery of this flow path. This inflow passage 11 is provided with a nozzle v14. A sphere 15 is inserted into the annular channel 13, a transparent window 17, 17' is formed, and a light emitting element 36 and a light receiving element 19 are provided. In such a configuration, when fluid enters the annular channel 13 from the nozzle 14 of the inflow channel 11, the flow flows from the inflow channel 11 to the outflow channel 12 while circulating in the annular channel 13, and the sphere 15 also flows as shown in the figure. It moves around inside the annular flow path 13 in the direction of the solid arrow. Since the rotational speed of the sphere is proportional to the flow rate of the fluid, the rotational speed of the sphere 15 is detected as a pulse signal by the light emitting element 36 and the light receiving element 19, and the flow rate is measured through the control circuit.

Problems to be Solved by the Invention However, in the above configuration, the annular flow path 13 is formed,
A light emitting element 36 and a light receiving element 1 are sandwiched from a direction perpendicular to this annular channel 13 (the orbital surface of the sphere 15), and the lead portions 20 and 20' of the light emitting element 36 and light receiving element 18 are , each terminal /l/
32.32' through the respective leads 27.27
When the light-emitting element 36 and the light-receiving element 18 are attached, they are electrically connected to the light-emitting element 36 and the light-receiving element 18, respectively.

Screw 35. It is an F4M configuration that is tightened at 35' and has many electrical connection points, and the number of parts to be installed is relatively high in terms of cost compared to the required functions. Since they are installed in 5 opposite directions, it takes up a lot of space, and is suitable for recent fluid equipment such as warm water flush toilet seats, automatic water heaters, etc., which are required to be smaller, more compact, and lower in cost. It had problems such as difficulty in adapting.

In terms of performance and reliability, the dish-shaped channel 13 (sphere 15
Due to the configuration in which the light emitting element 36 and the light receiving element 19 are sandwiched in a direction perpendicular to the orbital surface of
C, the time during which the ball blocks light becomes shorter, and as a result, it becomes difficult to detect it as a pulse signal, and it is even more difficult to detect it due to noise, ambient light, etc.

Furthermore, when tap water or the like is used as a fluid to be detected for a long period of time, Ca ions, Mg ions, etc. contained in the tap water adhere to the inner wall of the annular channel 1 in the form of scales, causing the light emitting element 36
This has led to problems such as light from the light receiving element 18 becoming difficult to reach and becoming undetectable.

Means to solve the problem And the technical means of the present invention to solve the above problem are as follows:
A spiral chamber having a circular cross section, and an inlet provided in a tangential direction to the outer circumference of the spiral chamber through which fluid flows.

A translucent spiral case having an outlet through which fluid flows out, a ball provided so as to be able to revolve within the spiral case, a detection means consisting of a light-emitting element and a light-receiving element for detecting the number of rotations of the ball, and a light-emitting element. and a waveform shaping circuit that shapes the signal waveform detected by the light receiving element, and a calculation means that calculates the flow rate of the fluid based on the pulse signal output from the waveform shaping circuit.

The optical axis from the light emitting element to the light receiving element is arranged so as to pass almost on the orbit of the ball, and the lead parts of the light emitting element 6, ... and the light receiving element are arranged substantially parallel to each other with the spiral case in between. The tips of the lead portions of the light emitting element and the light receiving element are wired on a single substrate.

Function In the present invention, the optical axis from the light emitting element to the light receiving element is provided so as to pass approximately on the orbital surface of the ball,
In addition, the lead parts of the light emitting element and the light receiving element are arranged approximately parallel to each other with the spiral case in between, and the tips of each lead part are wired to the second board, making electrical connection possible. , can be connected at once on the same plane. Since the spiral case is sandwiched so that the center of the optical axis almost passes through the orbital surface, when the ball revolves around the spiral chamber, it passes from the light emitting element section to the light receiving element section, thereby blocking light. can do.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.

FIG. 1 is a horizontal sectional view showing an embodiment of a flow rate detection device;
FIG. 2 is a longitudinal sectional view of the same.

Reference numeral 1 denotes a spiral case made of a translucent resin, such as polysulfone resin, which includes a spiral chamber 2 having a circular vertical cross section, and an upward direction (V
The inlet 113 arranged in the horizontal direction (direction) and the outlet 4 arranged in the horizontal central axis direction (H direction) of the swirl chamber 2 are integrally formed.

5 is a ball that orbits the swirl chamber 2 in a substantially vertical direction due to the vortex flow of the fluid to be detected, and the ball is made of an opaque color that does not reflect light and is slightly harder than the swirl case 1. Costume.

The outer diameter (φd) of the ball 5 is equal to the inner diameter (φd) of the spiral chamber 2.
The size is approximately 1/2 that of D).

6 is an outlet 4 from the tip 2a of the substantially conical portion of the swirl chamber 2 so that the bow/I15 does not flow into the outlet 4 of the swirl chamber 2.
It is a conical protrusion that protrudes in the direction 1 and has the function of promoting the swirling movement of the fluid to be detected that has flowed in from the inlet 3 .

7 is an OIJ ring for sealing the fluid to be detected.

9.8 is a light emitting element and a light receiving element, respectively, and the optical axis center X-X passes on the orbit plane indicated by the locus of the center of the ball due to the circular movement of Baud/115 on the outer peripheral side of the spiral case 1. The spiral case 1 is sandwiched between the light emitting element 9 and the light receiving element 8, and the center line CP-P bisects the circle φD of the cross section of the spiral chamber 2 on the orbiting plane of the ball 5. They are placed at different distances from each other.

That is, if the distance from the center line (P-P) to the light receiving element 8 is 411, and the distance to the light emitting element 9 is nl, then el<
It is set as a2.

For example, if the outer diameter of the ball 5 (φcl/)-8+nm and the inner diameter of the swirl chamber 2 (φD)-16*m, in the experiment, el
-4.5 tnm, 62=8+nlI is best.

10 is a light-shielding cover, which blocks external light by covering the light-emitting element 9, the light-receiving element 8, and the spiral case 1;
The lead parts 3o of the three light emitting elements 9 and the lead parts 31 of the light receiving element 8 are connected to each other with the spiral case 1 in between. The lead portions 30 and 31 are arranged substantially parallel to each other.
The ends thereof pass through through holes 32 and 33 provided in the light-shielding cover 10, and are electrically connected by soldering or the like to a single planar substrate 34 on which a circuit is configured by printing a wiring pattern.

35 is a screw that attaches the board 34 to the spiral case 1 via the light-shielding cover 10.

25, 26, and 27 are resistors, respectively, and 28 is an NPN transistor, which are waveform shaping circuit components that further shape the rotational speed of the ball 5 and the signal detected by the light receiving element 8 and output it to the microcomputer 30.

A board 34 printed with an electric circuit as shown in FIG. 3 is soldered.

36 is a lead wire for outputting the waveform-shaped pulse to the microcomputer 30.

Reference numerals 37 and 38 are element regulating walls integrally formed with the spiral case 1, and are provided to align the optical axis from the light emitting element to the light receiving element 18 with the orbital surface of the Baud/I 15.

10...-1 Next, the operation in the above 11G configuration will be explained with reference to FIGS. 1 to 4.

When fluid flows into the swirl chamber 2 from the direction of the arrow V, the fluid swirls around the swirl chamber 2, and accordingly, the bow) v5 also orbits in a substantially vertical direction without contacting the inner wall of the swirl chamber 2.

This ball 5 has a characteristic of rotating in proportion to the flow rate of the fluid. Therefore, to measure the flow rate, it is sufficient to measure the rotational speed of the baud (v5) that rotates in proportion to the flow rate.

In this embodiment, by arranging the light-emitting element 9 and the light-receiving element 8 on the orbital surface of the ball 5 with the spiral case 1 in between so that the optical axis centers of the light-emitting element 9 and the light-receiving element 8 almost pass through, the light-emitting element When blocking the light emitted from the baud/I15 force S (in Fig. 5, the baud/I1
The difference in the current flowing through the light-receiving element 8 between when the ball 5 is present (when the ball 5 is present) and when it is transmitted (when the ball 5 is at the position indicated by the β angle in FIG. 5) is converted into a pulse by a suppression circuit. is used as the flow rate signal.

In other words, when the ball 5 is at the position shown by the angle β in FIG. 6, current flows through the light receiving element 8, and the voE voltage is approximately 0.2 V.
Tonari NPN) The raster 28 outputs 0FFL, and the output 29 outputs a HI times signal. On the other hand, when the ball 5 is at the position indicated by the α angle in FIG.
N) If the base potential of the range nut 28 is high, it is turned on and the output 29 is L.

The full amount of color is generated.

Therefore, as shown in FIG. 4, when the flow rate is high, the cycle becomes short, and when the flow rate is low, the cycle becomes long.

According to this embodiment, as described above, the spiral cake 1fjr
: Since the centers of the optical axes of the light emitting element 9 and the light receiving element 8 are arranged so that they almost pass on the orbital surface of the ball 6, the time to block the light entering the light receiving element 8 from the light emitting element 9 is increased. As a result, even when detecting a high flow rate, light blocking and transmission can be clearly extracted as a pulse signal.

By inputting a stable pulse signal to the microcomputer 3o without being affected by noise, ambient light, etc., highly reliable flow rate detection can be performed.

According to this embodiment, the light-emitting element 9 and the light-receiving element 8 are arranged at different distances from the center line PP, which divides the circle φD of the cross section of the spiral chamber into three equal parts, on the orbital plane of the ball. ing.

That is, as shown in FIG. 1, I;11. e2 is 4.5+n
+ao and 8 dragons. This is the spiral chamber diameter φD-
16 and the outer diameter of the ball φd=8, this is the value that yields the most output, which was determined empirically. -t In other words, in a transmission type light detection method in which a light emitting element, a light receiving element, etc. are provided on the orbital surface from the outer circumferential direction of the circle around which the ball revolves,
As mentioned above, it is better to make the layers from the center line p-p that divides the circle φD around which the ball goes around into three equal parts to the light-receiving element and the light-emitting element from each other in terms of the degree of refraction of light, etc. This is the best arrangement.

However, according to this embodiment, the ends of the lead parts 30 and 31 of the light emitting element 9 and the light receiving element 8, and the NPN l-transistor 2
8. The waveform shaping circuit components including the resistors 25, 26, 27, etc. are arranged directly on the second board 34, so they are not easily affected by external noise.

Effects of the Invention As is clear from the description of the above embodiments, the flow rate detection device of the present invention is provided such that the optical axis from the light emitting element to the light receiving element passes approximately on the orbit of the ball, and the light emitting element The IJ leads of the photodetector are arranged approximately parallel to each other with the spiral case in between, and the tips of the respective leads are wired to a single board, so the number of parts is small and electrical connections are easy. Since they can be connected all at once on the same plane, productivity can be increased and a low-cost flow rate detection device can be provided.

Furthermore, in terms of performance and reliability, the optical axis from the light-emitting element to the light-receiving element is located on the orbital surface of the ball, so when the ball orbits the spiral chamber, light is blocked from the light-emitting element to the light-receiving element. Even if the measured fluid has a high flow rate and the ball rotates at high speed,
It can be extracted as a stable pulse signal, and is not affected by noise, ambient light, etc. (highly reliable flow rate detection can be provided).

In addition, since the lead portions of the light emitting element and the light receiving element are configured so that their lead portions are taken out in substantially parallel directions, the size is relatively compact, and it can meet the recent demands for miniaturization of equipment.

[Brief explanation of the drawing]

FIG. 1 is a horizontal cross-sectional view of a flow rate detection device showing an embodiment of the present invention, FIG. 2 is a view showing the state of light shielding and transmission through a vertical cross-section of the flow rate detection device, and FIGS. 6 and 7 are FIG. 2 is a horizontal cross-sectional view and a cutaway vertical cross-sectional view of a flow path of a conventional flow rate detection device. 1... Spiral case, 2... Spiral chamber,
3... Inlet, 4... Outlet, 5...
...ball, 8...light receiving element, 9...
・Light emitting element, 25.26.27...Resistance, 2a.
...NPN) transistor, 30...Lead part of light emitting element, 31...Lead part of light receiving element, 3
4... Board. Name of 1 representative Patent attorney Toshio Nakao and 1 other person --- 5-〇 へ 5- 〇 へ 5 - Shoulder elbow L 6 Figure 7

Claims (1)

[Claims] A translucent spiral case having a spiral chamber having a circular cross section, an inlet provided in the tangential direction of the outer circumference of the spiral chamber through which fluid flows in, and an outlet through which the liquid flows out; a ball provided in the ball, and a detection means comprising a light emitting element and a light receiving element for detecting the rotation speed of the ball;
A waveform shaping circuit that shapes the signal waveform detected by the light emitting element and the light receiving element, and a calculation means that calculates the flow rate of the fluid based on the pulse signal output from the waveform shaping circuit, the light emitting element reaching the light receiving element. The shaft is provided so as to pass approximately on the orbit of the ball, and the lead portions of the light emitting element and the light receiving element are arranged approximately parallel to each other with a spiral case in between, and the lead portions of the light emitting element and the light receiving element are arranged substantially parallel to each other with a spiral case in between. The tip of the is a flow rate detection device that is wired onto a single board.