JPH0262914A - Rotary body for turbine type flowmeter - 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 the Invention The present invention relates to a rotating body for a turbine-type flowstone meter, and more particularly to a turbine-type flowstone meter configured so that a ball that contacts a bearing can be incorporated into the shaft portion of the rotary body with high precision. Regarding rotating bodies.

BACKGROUND OF THE INVENTION Conventional technology A turbine-type outflow meter for measuring the flow (h) of fluid such as city gas (hereinafter referred to as gas in this example);
The rotating body for a turbine-type flow meter, which is used to measure minute flow rates of 51 hours or less, has an impeller that rotates according to the flow rate, and both ends of the rotating shaft are machined into a spherical shape, and the rotating body faces the impeller. The rotating shaft was supported by a bearing part. However, in the conventional rotating body mentioned above, the material quality of the rotating shaft was high, so the dimensional accuracy between both ends of the rotating shaft was low, and the spherical viscosity was also low. In addition, various types of rotating bodies are being used to solve the above problems. The proposed turbine-type rotating body for flow training is, for example, provided with recesses at both ends of the 0-rotation shaft, and balls placed in the recesses. F. The periphery of the human population and the county area (
(Japanese Unexamined Patent Publication No. 62-215826), ■ Gluing or press-fitting balls into the hollow parts at both ends of a cylindrical rotating shaft (Japanese Unexamined Patent Publication No. 62-215826)
0-74497), ■ A method of inserting a highly viscous positioned center shaft into the hollow part of a cylindrical rotating shaft and positioning the balls by abutting both ends of the center shaft/j and then caulking both ends of the rotary shaft 111. (Japanese Utility Model Application No. 61-190819), (1) The impeller and the shaft portion having a recessed portion at the end are integrally molded, and one ball that contacts the fixed bearing portion is fitted into the recessed portion (Japanese Unexamined Patent Publication No. 62-1908).
2151327), etc. have been considered.

Problems to be Solved by the Invention However, in the above-mentioned rotating body for a turbine-type rhyometer, it is difficult to precisely machine the concave portion of the rotating shaft due to the concentricity of the ball and the rotating shaft, and the It was not possible to incorporate the coaxiality of the ball and the exposed area of the ball after caulking with high precision and without any variation. In addition, in (2), the ball is fixed with adhesive, so there is a risk that the temperature is -4 degrees below. In addition, in ■, there are many machining of the rotary shaft and center shaft, fixing of the ball, insertion of the rotary shaft into the impeller, and addition, and all of these require precision machining. A construction cost is high 1 convex.

In addition, since the shaft part in the above case (■) is made of synthetic resin, there is no gap between the ball and the bearing at high temperatures due to the difference in linear expansion coefficient between the metal flow fflAl main body, the upper part, and the flow side cone snow'. Another problem is that at low temperatures, the gap between the ball and the bearing becomes large, which may prevent the rotating body from rotating smoothly.

Therefore, the present invention proposes a tardon type 2 that solves the above-mentioned problems.
i(The purpose is to provide a rotating body for HLil.

Means and operation for solving the problems The present invention has a metal shaft embedded in the center of the shaft of a synthetic resin rotating body that rotates according to the flow rate of the fluid to be treated,
A hole is formed in the rotating body so as to reach both 9f portions of the metal shaft, and a ball that comes into contact with a bearing fixed on the upper and downstream side of the rotating body is inserted into the hole, and the ball is inserted into the shaft. The ball is placed in contact with the end of the ball, which increases the accuracy of ball mounting without requiring much effort, and allows for flow rate measurement and stable rotation.

Embodiment FIG. 1 shows a turbine type flow rate control to which an embodiment of the turbine type flow loss rotary body according to the present invention is applied.

Figure 2 shows the main parts of the rotating body. .

In both figures, a targon type flow f71.31 is shown in blue in the flow path 1 of the piping so as to measure the flow rate of gas passing through the flow path 1 of the piping. Reference numeral 2 denotes a rotating body, which is formed by insert molding a metal shaft 4 at the center of a rotating body body 3 made of synthetic resin.

As shown in FIG. 2, both ends of the shaft 4 are tapered, and conical recesses 4a and 4bffi are provided at both ends. In addition, the shaft 4 is made of stainless steel or carbide, for example.
Since it is obtained by cutting a round bar material such as . In this embodiment, conical recesses 4a, 4bf are formed at both ends of the shaft 4! : Installation) However, both ends of @4 may be flat. The reason why the shaft 4 is tapered at both ends is to increase the strength of the shaft 4 itself by making the outer diameter of the shaft 4 as thick as possible.

The rotating body 3 has a plurality of blades 3C on the outer periphery of the hub, and holds magnets 1-16 for rotation detection on the inner wall of the hub.
Further, both ends of the shaft portion of the rotating body body 3 having the above-mentioned hood 4 inserted into the inner periphery of the hub are provided with recessed portions 4a and 4 at both ends of the Td14.
Holes 3a and 3b are formed so as to reach b. The inner walls of the holes 3a, 3b are concave in a spherical shape.
Balls 5a and 5b are press-fitted inside b.

The balls 5a and 5b are made of carbide, ceramic, jewelry (S
iC, Ruby, AP, 20i, etc.), and its sphericity and dimensional accuracy F are extremely high values. In general, the technology for manufacturing spheres has been established, and spheres with high precision can be manufactured relatively easily and at low cost. ,Also,
The balls 5a and 5b have extremely high hardness and are more rigid than the rotating body 3 made of synthetic resin.

The rotor main body 3 has an elastic modulus of, for example, 1xlO5Ky/α2 or less, and the balls 5a and 5b are holes 3a.

When pushed into the ball 3b, the holes 3a, 3b expand slightly in the outer circumferential direction to hold the balls 5a, 5b (1).

Further, the balls 5a, 5b are held in the holes 3a, 3bk, and are positioned by coming into contact with the conical recesses/1a, 4b.

Therefore, the balls 5a and 5b are assembled so as not to be misaligned with respect to the axis of the shaft 4. Note that the balls 5a, 5b press-fitted into the holes 3a, 3b have a part of their outer periphery formed into the hole 3a, as shown in FIG.

Make it protrude from 3b.

Further, in FIG. 1, 6.7 is a pivot l111 made of a hard material such as sapphire! The receiver has four spherical surfaces 6a, 7a on which the balls 5a, 5b of the rotating body 2 slide. The upstream pivot 1rllll receiver 6 is provided on the upstream cone 8, and the downstream pivot bearing 7 is provided on the downstream cone 9.

The upper and downstream cones 8.9 each have a D-rad 11.
It has 12. Each lug 8.9 is fixed to the support frame 10 by tightening a nut 13.1/I screwed into the externally threaded portions 11a, 12a of the rod 11.12.

The rotating body 2 is arranged between the upper and downstream cones 8 and 9, and the balls 5a and 5b are connected to the four spherical parts 6 of the pivot thll receivers 6 and 7.
It is rotatably supported in sliding contact with a and 7a.

15 is a pickup consisting of a magnetic sensor, etc., and a rotating body 2
It is provided on the upstream cone 8 to face the magnet 16, and outputs a pulse signal by detecting passage of the magnet 16.

Here, the 51 measurement operation of the 100 turbine type flow rate 51 will be explained.

In FIG. 1, when gas is fed through the flow path 1 in the direction of the arrow, the gas passes through the blades 3C of the rotating body 2 and flows downstream. The vane Fji2 rotates at a rotational speed proportional to the flow rate flowing through the flow path 1.

As mentioned above, the shaft 4 of the rotating body 2 is insert-molded, so the strength of the shaft is high, and the balls 5a,
5b has a high degree of concentricity with the shaft 4 due to its contact with the recesses 4a and 4b. Therefore, the rotating body 2 rotates stably according to the flow rate of the gas 1, and since the metal shaft 4 is molded in-1 inside the rotating body 2, the shaft of the rotating body 2 and the pivot bearing 6 On the right side of .7, the linear expansion coefficients of the cone 8.9'S on the downstream side are approximately equal. Therefore, even if the temperature changes by 1σ, the gaps between the balls 5a, 5b and the four spherical surfaces 6a, 7a of the pivot bearings 6.7 hardly change, and the rotating body 2 remains stable without being affected by temperature changes. Rotating crane 1
The rotation speed of the rotating body 2 is detected by the pickup 15 which outputs a pulse signal as the magnet 16 passes.

Then, the pulse signal from the pickup 15 is sent to an amplifier (
The flow is supplied to the flow ω finger small portion (I!f shown) via the flow rate (not shown), and is converted into a flow rate.

Next, the manufacturing process of the rotating body 2 will be explained with reference to FIGS. 3 to 7.

First, as shown in FIG. 3, the shaft 4 is manufactured by cutting a round bar material such as stainless steel. 1. That is, after cutting a long round bar material to the full length of the shaft 4 and processing the outer diameter to the dimension d, both ends of the shaft 4 are cut into a tapered shape. Conical recess 4a.

4b is JjG ined by a drill (1' shown)@. .

It is attached to a mold for injection molding with a 4μ axis which has been processed as described above. In FIG. 4, the shaft 4 is connected to the fixed mold 17 and the movable mold 18.
The fixed mold 17 and the movable mold 18 are shown installed in a cavity 19 formed between the rotating body 3 and the rotary body 3. It is precisely machined. A pin 20 is attached to each mold 17, 18, and has a tip 20a that fits into the recesses 4a, 4b of the shaft 4.

The end of the tip 20a has a circular zU-shaped protrusion corresponding to the recesses 4a, 4b, and the outer periphery of the tip 20a has balls 5a, 5b1. 1, which has a corresponding spherical shape. Therefore, with the recess 4a of the shaft 4 applied to the tip 20af of the pin 20 of the fixed mold 17, move the movable mold 18 in the direction of the arrow X2. When U, the concave part on the other end side of +1 Haku4/! The tip part 20a of the b pin 20 is fitted into b, and the shaft 4 is held at both ends. Next, runner 1 of fixed mold 17
Molten Ea resin is injected from 7a. Molten resin is gate 1
7b and is filled into one four-way cavity. As a result, the space between the shaft 4, the fixed mold 17, and the movable mold 18 is filled with molten resin, and the surface of the shaft 4 except for the tip 20a of the pin 20 is coated with the resin. Therefore, since the shaft 4 is positioned at the center of one 4-way cavity by the engagement of the recesses 4a and 4b at both ends and the tip 20a of the pin 20, the shaft 4 is insert-molded at the center of the axis of the rotary body 3. Ru.

The concave portions 4a and 4b of the shaft 4 are machined with high precision, and injection molding is performed as described above using the molds 17 and 18 processed to have a high viscosity. 4
The dimensional accuracy of the concentric ring and the rotating body 2 is formed with high precision.

After filling the molten resin as described above, the molds 17 and 18 are cooled. Next, the movable mold 18 is slid away in the direction of arrow x1, and the injection-molded rotating body 2 shown in FIG. 5 is taken out.

Note that the hole 3 of the rotating body body 3 is formed as shown in FIG.
The inner diameter L1 of a and 3b is L+<L with respect to the diameter of balls 5a and 5b. Further, the depths of the holes 3a, 3b and the recesses 4a, 4b satisfy the relationship L2<1/2.

Next, as shown in FIG. 6, the hole 3a of the rotating body body 3 is formed with the shaft 4 inset molded therein as described above.

3b, press the balls 5a and 5b as shown by the arrows. Since the holes 3a and 3b have elasticity, the balls 5 with high hardness
When a and 5b are pushed in, the diameter of the ball 3 expands in the outer circumferential direction, so that the balls 5a and 5b form the hole 3a.

The outer periphery is pressed and held by the elasticity of 3b itself, and
It is positioned by coming into contact with circular concave portions 4a and 4b.

In this way, the rotating body 2 shown in FIG. 7 is easily manufactured. By contact with the concave portions 4a, 4b at both ends of the shaft 4, which are formed inset at the center of the shaft of the rotary body 3, the balls 5a, 5b are rotated without misalignment. Further, the amount of protrusion of the balls 5a, 5b from the holes 3a, 3b is -111114 at the fourth portion 4a.

By increasing the machining accuracy of 4b, the accuracy can be controlled with good accuracy.

Effects of the Invention As described above, the rotating body for a turbine bottom flow meter according to the present invention has a metal shaft inset molded at the center of the rotating body body using a highly precisely machined mold, and the end of the shaft is Since one ball is inserted into the hole leading to the end, it is easy to produce a high-quality rotating body with high concentricity between the rotating body and the shaft, as well as between the shaft and the ball, and with high concentricity between the balls at both ends. Moreover, since the ball is not fixed by caulking or glued as in the conventional method, the number of man-hours required is small and the manufacturing cost is low. Furthermore, by inserting a metal shaft into the center of the rotating body, changes in the gap between the ball and the bearing that occur due to temperature changes can be suppressed, and stable flow measurement performance can always be maintained. have

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a turbine-type flow rate a1 to which an embodiment of the PA of the rotating body for turbine-type seedling bar 1 according to the present invention is applied, and FIG. 2 is a vertical cross-sectional view showing an enlarged main part of the present invention. Fig. 3 is a diagram showing the shape of the shaft that has been cut, Fig. 4 is a cross-sectional view of the shaft shown in Fig. 3 mounted on a mold for molding.
Figure 5 is a longitudinal sectional view of the molded rotating body, Figure 6 is a vertical sectional view for explaining how the ball is inserted into the hole in the body of the rotating body, and Figure 7 is a vertical sectional view of the ball being assembled ( It is a vertical sectional view of the main part of the rotating body. 2... Rotating body, 3... Rotating body main body, 4... Shaft, 4
a. 4b...concavity, 5a, 5b...ball, 6,7...
・Pivot bearing, 17... Fixed mold, 18... Movable mold 4; 1.20... Pin. Patent Applicant: Tokiko Co., Ltd. Tokyo Gas Co., Ltd. Osaka Gas Co., Ltd. Toho Gas Co., Ltd. Representative: Tadahiko Ito, Chief Priest: Kaneyuki Matsuura Figure Figure Figure

Claims (1)

[Claims] A metal shaft is embedded in the center of the axis of a synthetic resin rotating body that rotates in accordance with the flow rate of the fluid to be measured, and holes are formed in the rotating body so as to reach both end portions of the metal shaft. , a turbine flowmeter characterized in that a ball that contacts a bearing fixed above and downstream of the rotating body body is fitted into the hole, and the ball is brought into contact with an end of the shaft. Rotating body.