JPH04324320A - Electromagnetic flow rate meter - Google Patents

Abstract

PURPOSE:To make a liquid-contact portion inexpensive and disposable. CONSTITUTION:A detector S which constitutes a liquid-contact portion consists of an electrode E for taking out a flow rate signal, a ground pipe G which plays a role of both a hose VH for enabling a fluid to flow and a ground electrode for providing an earth, a plastic meter tube which press-fits and fixes these watertightly, and a coil for excitation C. This detector S is retained by a clamp K, thus achieving electrical connection to the coil C, the electrode E, and the ground pipe using a wire which is provided at the clamp K.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disposable electromagnetic flowmeter used for measuring pharmaceuticals, chemicals, fertilizers, agricultural chemicals, etc.

0002

[Prior Art] Electromagnetic flowmeters are widely used for industrial flow rate measurement, but because they are intended for long-term outdoor use, the flow rate detection part has a complicated structure such as a metal case in order to be environmentally resistant. and is expensive. Furthermore, when measuring chemicals, expensive metals such as platinum are used for the wetted parts to ensure long-term corrosion resistance. Therefore, the flow rate measurement unit is expensive, ranging from 100,000 yen to several hundreds of thousands of yen.

[0003] On the other hand, disposable flowmeters are required for safety and hygiene in pharmaceutical products, in order to avoid mixing of chemicals and to save time and effort for cleaning chemicals and agricultural chemicals. However, there was no such product that was so cheap that its wetted parts were disposable.

0004

[Problem to be solved by the invention] Recently, the mixing and
In order to improve the performance (accuracy of amount and time) of spraying, injection, and transportation, there is a need for flowmeters that measure flow rates.

However, from the viewpoint of ease of use and safety, it is required that the parts in contact with the liquid be disposable, so the flow rate detection part must be inexpensive. Therefore, an object of the present invention is to provide an electromagnetic flowmeter in which only the liquid-contacting part has a disposable structure, and the liquid-contacting part can be manufactured at a low cost of several hundred yen.

[0006] Regarding chemical resistance, by making it disposable, the usage time can be shortened to about one day, and sufficient chemical resistance can be ensured within the usage time without using expensive precious metals for electrodes and the like.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the electromagnetic flowmeter of the present invention has a coil (C) that generates a magnetic field.
), an electrode (E) that takes out the flow rate signal, a ground pipe (G) that serves as a connection fitting for the hose (VH) that flows the fluid, and a ground electrode that takes the ground point, and a pipe that has an insulated inner surface through which the fluid flows. a detector (S) consisting of a plastic integrally molded meter tube (T) into which the coil (C), the electrode (E) and the ground pipe (G) are assembled; and the detector (S) is held. along with a wiring wire (W) for electrical connection to the detector (S)
It is characterized by comprising a clamp (K) equipped with.

[0008]

[Operation] When the detector is held in the clamp, electrical connections are made to the coil, electrode and ground pipe. Furthermore, by connecting a hose to the ground pipe and flowing fluid, a flow rate signal is obtained at the electrode, and the fluid flow rate is measured.

When used in a medical infusion device, after use,
Remove the detector and hose and discard.

0010

[Example] In the example shown in the figure, C is an excitation coil that is glued to one side of a coil mount CM made of a printed board, and both ends of the winding of the coil are coils that are the foil part of the printed board body of the coil mount CM. It is soldered to contact CC.

[0011] T is a meter tube made of an integrally molded plastic product, which is electrically insulating, and has a fluid passage passing through its center. Since it is integrally molded, it contributes to making the overall structure cheaper. E is a nail-shaped electrode that takes out the flow rate signal, and G is a ground pipe made by cutting a tube made of SUS304 to 316. It serves both as a connection fitting for the hose VH that flows the fluid and as a ground electrode that takes the ground point. E and the ground pipe G are press-fitted into the meter tube T in a watertight manner, contributing to a reduction in assembly costs.

The coil C and coil mount CM are shown in FIG.
It is adhesively fixed to the meter tube T as shown in (a). TSQ is a square portion formed at both ends of the meter tube T, and is used for positioning during clamping, as will be described later.

[0013] K is a clamp, which includes a clamp body B shaped like a washing scissor, a spring D that applies a clamping force, a grip part BSQ formed on the clamp body B and which grips and fixes the square part TSQ, and a clamp. It is movably held by body B and is pressed by a spring, and the tip is a coil contact C.
Coil contacts CPI to CP4 that should be in contact with the ground pipe G; electrode contacts EP that are in the shape of a leaf spring and should be in contact with the head of the electrode E; and a ground that is formed from a press-cut product of a thin spring plate and should be in contact with the ground pipe G. Contact GP1~
GP2 and each contact CP1 to CP4, EP, GP1
- Wiring W electrically connected to GP2.

A is an amplifier that amplifies the flow signal induced in the electrode E and supplies an excitation current to the coil C. C.B.
is a cable connecting between the wiring W of the clamp K and the amplifier A.

VH is a hose made of vinyl or the like through which fluid flows, and is used by being connected to the ground pipe G of the detector S. As shown in FIG. 1(b), the detector S is held with a clamp K with a hose VH connected to its ground pipe G, and the electric wire W of the clamp K is connected to the coil C, the electrode E, and the ground pipe. Make electrical connections.

[0016]

[Effects of the Invention] Since the electromagnetic flowmeter of the present invention is constructed as described above, the structure of the disposable detector S is simplified, and the troublesome wiring is provided in the clamp K, so that it can be used as a medical infusion device. An electromagnetic flowmeter that is suitable for use and whose disposable part (detector) is inexpensive can be realized.

[Brief explanation of drawings]

FIG. 1 is an embodiment of the present invention, in which (a) is a longitudinal sectional front view of a detector, and (b) is a perspective view of the entire detector.

FIG. 2 shows a detector used in an embodiment of the present invention, in which (a) is a plan view and (b) is a longitudinal cross-sectional side view.

FIG. 3 is a perspective view of a meter tube used in an embodiment of the present invention.

FIG. 4 is a perspective view of a coil mount used in an embodiment of the present invention.

FIG. 5 is a perspective view of a coil used in an embodiment of the present invention.

FIG. 6 is a perspective view of a coil mounted on a coil mount according to an embodiment of the present invention.

FIG. 7 is a longitudinal sectional side view of a clamp in an embodiment of the present invention.

FIG. 8 is a schematic front view of a clamp in an embodiment of the invention.

FIG. 9 is an electrical circuit diagram of an embodiment of the present invention.

[Explanation of symbols]

C Coil E Electrode G Grand pipe K Clamp S Detector T meter tube VH Hose W Electric wire

Claims (1)

[Claims] Claim 1: A coil (C) that generates a magnetic field, an electrode (E) that extracts a flow rate signal, and a hose (VH) that flows a fluid.
) and a ground pipe (G) that serves both as a connection fitting and a ground electrode for taking a ground point, and a pipe with an insulating inner surface through which fluid flows, and the coil (C) and electrode (E).
Detector (S) consisting of a meter tube (T) integrally molded with plastic and incorporating a ground pipe (G).
and a clamp (K) equipped with a wiring wire (W) for holding the detector (S) and electrically connecting to the detector (S). Total.