JP3085761B2 - Fluid vibration type flow meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid vibration type flow meter which can be manufactured with high productivity and high quality.

[0002]

2. Description of the Related Art In recent years, as a flow meter having no mechanical movable part and not depending on the physical properties of a fluid, a fluid formed by sequentially forming a jet nozzle, a columnar target, and a throttle portion in a flow meter body toward a downstream side. A vibratory flow meter is known. This is based on the phenomenon in which the direction of the jet ejected from the ejection nozzle alternately deflects to both sides of the columnar target at a frequency proportional to the flow rate, regardless of the physical properties of the fluid (fluid oscillation), and is detected from changes in pressure, etc. The flow rate is calculated based on the frequency of the fluid vibration, and is displayed.

[0003]

However, conventionally,
In the above flowmeter, since the flowmeter main body is formed integrally with an aluminum casting or the like, the ejection nozzle and the columnar target cannot be manufactured to a desired shape with high precision, and the theoretical performance cannot always be stably exhibited. Was.

That is, despite the fact that the shape of the jet nozzle or the like greatly affects the above-described properties of the fluid vibration, even if a high-precision casting method called precision die casting is used, a mold called a draft is removed. Must be provided at least in a slight amount on the surface on which the ejection nozzles and the like are formed, and there is a problem that the inclination causes a shape error and deteriorates performance stability.

[0005] In general, precision die casting has low mold durability and high manufacturing cost. Therefore, it has been difficult for conventional fluid vibratory flowmeters to be manufactured efficiently at low cost while maintaining reliability.

The present invention has been made in view of the above circumstances, and has as its object to provide a fluid vibration type flow meter which can be manufactured with high productivity and high quality.

[0007]

SUMMARY OF THE INVENTION A fluid vibration type flow meter according to the present invention comprises a metal casing having an element-incorporating groove formed therein, and a resin oscillation set in the element-incorporating groove of the casing. And an ejection element and a columnar target are integrally formed in the oscillation element.

[0008]

With the above construction, the ejection nozzles and the like relating to the performance as a flow meter can be manufactured separately from the casing by integral molding of a resin that does not require a draft angle, so that the shape or relative positional relationship of the ejection nozzles and the like can be obtained. Can be optimized with high accuracy and theoretically. The airtightness or pressure resistance of the entire flowmeter main body can be ensured by a metal casing, and since this casing does not require high precision, it can be easily and inexpensively manufactured by ordinary casting. Therefore, according to the present invention, a high-quality flowmeter having high performance as a flowmeter and ensuring other necessary performances such as airtightness can be manufactured with high productivity.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing a flow meter main body of the present embodiment. In FIG. 1, what is indicated by reference numeral 1 is a casing. The casing 1 is made of a metallic material formed by die-casting aluminum or the like so as to have pressure resistance and airtightness. The casing 1 has a connection port 1a as an inlet and a connection port 1b as an outlet. Is formed in a box shape having a rectangular cross section that opens upward as shown in FIG.
Is sealed by a metal lid 2 via a gasket 3 while maintaining pressure resistance. Reference numeral 4 denotes this lid 2
4 shows a screw hole for fastening the. In this box-shaped portion, an inflow portion 5 for introducing a fluid from the connection port 1a and an element-incorporating groove 6 into which an oscillating element described later is inserted are formed in a communicating state through a notch 7. 6 has an end communicating with the outlet connection port 1b.

Reference numeral 11 denotes an oscillating element manufactured by molding a resin such as polyacetal, for example, into the shape shown in FIG. 13, the throttle portion 14 is integrally formed. This oscillation element 11
As shown in FIG. 2, a pair of side walls 11b and 11c forming the jet nozzle 12 and the like and the columnar target 13 are formed to extend vertically from the plate-like base 11a with a constant cross-sectional shape. Side walls 11b, 11
Between c, a flow path 16 including the ejection nozzle 12, the enlarged cross-section portion 15, and the throttle portion 14 is formed. The ejection nozzle 12 is formed by squeezing the central portions of the side walls 11b and 11c. An enlarged cross-section 15 is formed in front of the ejection nozzle 12, and a flow path 16 is formed in the enlarged cross-section 15. A columnar target 13 that intersects at right angles with the jet nozzle 12 is disposed at a distance from the ejection nozzle 12, and a narrowed portion 14 is formed in front of the columnar target 13 with the end faces of the side walls 11 b and 11 c facing each other. The side walls 11b and 11c of the oscillation element 11 and the columnar target 13
Is formed at the same height as the depth of the casing 1 and is fitted into the element mounting groove 6 from the opening 1c of the casing 1, and a boss 17 provided on the bottom surface of the casing 1 is provided with a hole 11d of the base 11a. And is fixed in the element mounting groove 1c.

In FIG. 1, reference numeral 18 denotes a rectifying network arranged so as to partition the inlet side of the oscillation element 11, and this rectifier network is provided from the inflow section 5 of the casing 1 through the notch 7. This is for reducing the swirling flow generated by the bending of the flow path leading to the ejection nozzle 12.

The flow meter is connected to a flow path whose flow rate is to be measured through the connection ports 1a and 1b, so that the jet flow jetted from the jet nozzle 12 is deflected alternately with the columnar target 13 as a center. Therefore, by processing a signal output from a sensor (not shown) that detects a pressure or a flow velocity around the columnar target 13 in the fluid element 11, it is possible to know the flow rate without depending on the physical properties of the fluid as in the related art. it can.

In the case of the above-mentioned flow meter, the ejection nozzle 12 and the like related to the performance as the flow meter can be manufactured separately from the casing 1 by integral molding of a resin that does not require a draft. Alternatively, these relative positional relationships and the like can be made theoretically optimal with high accuracy. That is, in the resin molding of the oscillation element 11, for example, if the upper mold and the lower mold are arranged using the upper surface of the base 11a in FIG. 2 as a parting line, as in the case of the die casting, both side walls 11b, 11c, it is necessary to pull out the mold located between them in the upper part of FIG. 2. Even if the mold is straight in the pulling-out direction, Since the side walls 11b and 11c bulge outwardly, the mold does not need to have any draft. In addition, the airtightness or pressure resistance of the entire flowmeter main body can be ensured by the metal casing 1, and since the casing 1 does not require high precision, it can be easily and inexpensively manufactured by ordinary casting.

Therefore, a high-quality flowmeter having high performance as a flowmeter and ensuring other necessary performances such as airtightness can be manufactured with high productivity. For example, in order to stably generate fluid vibration in a wide measurement range and perform measurement with high accuracy, the applicant has filed Japanese Patent Application No. 2-24954.
As proposed by No. 1, the size or shape of the ejection nozzle 12 and the columnar target 13 and the like need to exactly satisfy certain conditions. However, there is an effect that high productivity can be secured while being obtained.

[0015]

As is apparent from the above description, according to the fluid vibration type flow meter of the present invention, the oscillating element related to the performance as the flow meter is formed of resin, so that the draft angle of the mold is reduced at the time of forming. Even if there is no resin, the resin can be flexed and the mold can be pulled out smoothly, and it can be made highly accurate and theoretically optimal. The pressure resistance and the like can be ensured by a metal casing. Therefore, a high-quality flowmeter having high performance as a flowmeter and ensuring other necessary performances such as airtightness can be manufactured with high productivity.

[Brief description of the drawings]

FIG. 1 is a sectional view of a flow meter main body.

FIG. 2 is a sectional view taken along the line II in FIG.

FIG. 3 is a perspective view of the oscillation element in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casing 11 Oscillation element 12 Spout nozzle 13 Columnar target 14 Throttle part

Continued on the front page (72) Inventor Hideaki Ikeda 1-3-6 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Tokiko Corporation (72) Inventor Kazuo Tsuge 1-3-6 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa Tokiko Stock Inside the company (72) Inventor Shigenori Okamura 3-2-95 Chiyozaki, Nishi-ku, Osaka-shi, Osaka Inside Osaka Gas Co., Ltd. (72) Inventor Hiroshi Ueda 3-2-295 Chiyozaki, Nishi-ku, Osaka-shi, Osaka Osaka Gas Co., Ltd. (58) Investigated field (Int.Cl. ⁷ , DB name) G01F 1/20

Claims (1)

(57) [Claims] 1. A metal casing in which an element-incorporating groove is formed, and a resin oscillation element fitted in the element-incorporating groove of the casing, wherein the oscillation element has an ejection nozzle. A fluid vibration type flow meter, wherein a columnar target is formed integrally.