JPS6021419A - Detector for electromagnetic flowmeter - Google Patents

Abstract

PURPOSE:To facilitate manufacture, by forming a semi-tubular linking part with the side of an open surface as a center at the upper part of a box shaped body, whose side forms the open surface, and forming a tapered part, which is inclined from the upper part to the lower part at the outer surface thereof. CONSTITUTION:At the upper part of a box shaped body 1, whose side forms an open surface, a semi-tubular linking part 2 is formed with the side of the open surface as a center. A tapered part 3, which is inclined from the upper part to the lower part, is formed at the outer surface thereof. A protruded step part 4 is formed on the side of the open surface. They are contacted when they are assembled and regulate the center of the cabinet of a detector. The periphery 5 of the open surface is formed so that it is slightly lower than the protruded step part 4. Thus a packing having a shape corresponding to the periphery 5 is readily provided. According to this constitution, manufacture can be made easy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a detector for an electromagnetic flowmeter.

[Prior art]

A detector for an electromagnetic flowmeter generally consists of a measuring tube through which liquid flows, an electromagnet for passing magnetic flux to the tube, and a detector installed inside the measuring tube to detect the electromotive force generated in the liquid in response to the magnetic flux. The measurement tube consists of electrodes and a housing that houses them.The measurement tube needs to be electrically insulated on its inner surface and connected to the pipe in a watertight manner at both ends. For this purpose, it must be non-magnetic, have a shape that allows liquid to flow uniformly at a predetermined flow rate, and have a strength that allows the measuring tube to support the entire detector when connected between pipes. requested.

Therefore, conventionally, a flange is welded to both ends of a stainless steel pipe, etc., and then two coats of insulating material are applied from the flange surface to the inner surface of the pipe, and the flange is connected to multiple pipe lines. In order to ensure measurement accuracy, the lining thickness needs to be thin to reduce fluctuations in lining thickness due to changes in aging or liquid temperature, but on the other hand, it needs to be thick in terms of durability. In addition to being difficult to set up, the lining requires special equipment and skill, resulting in high manufacturing costs.

Furthermore, since the connection with the pipe line is by a flange, the connection work is troublesome and there are also disadvantages such as difficulty in adapting to a small diameter pipe line.

On the other hand, the electrodes in the measuring tube must be placed opposite to each other along the central axis of liquid flow and perpendicular to the direction of magnetic flux. The measuring tube is fixed by a contact or the like, thereby regulating the mutual relationship between the measuring tube and the housing housing the electromagnet, which has the disadvantage that the number of assembly steps increases and it is difficult to improve productivity.

Therefore, in conventional detectors, a measuring tube with an inner diameter corresponding to the flow rate range to be measured is manufactured, the shape and dimensions of the housing and other parts are determined accordingly, and each part is manufactured for each flow rate range to be measured. However, there is also the drawback that it is difficult to share parts.

[Summary of the invention]

The present invention has the purpose of fundamentally solving the various drawbacks of the conventional art, and includes constructing a measuring tube by inserting an inner tube made of an insulating material into an outer tube made of a non-magnetic tubular body. - Two cases are used, each of which has a through hole for supporting a measuring tube in the side of a box-like body with open sides, and after inserting the end of the measuring tube into the through hole, the open surfaces are aligned with each other. The ends of the inner tube are fixed so that both ends of the inner tube protrude more than both ends of the outer tube. To provide an extremely effective detector for an electromagnetic flowmeter, which is brought into contact with an enlarged step provided inside a connecting part, and in which a seal ring is fitted to each of the outer circumferences at both ends of an inner pipe. Deroru.

〔Example〕

Hereinafter, the present invention will be explained in detail with reference to figures showing embodiments.

Figure 1 is from Guicast, etc.! (A) is a front view seen from the open surface, (A) is a vertical sectional view, (0 is a back view, (6) is a side view, and the - side is the open surface. A semi-cylindrical connecting part 2 centered on the open surface side is formed above the box-shaped body 1, and a tapered part 3 slanting from above downward and inward is formed on the outer peripheral surface of this. At the same time, a protruding step portion 4 is formed on the open surface side, and this is still in contact during assembly to regulate the center of the detector housing. It is formed slightly lower than the portion 4 to facilitate the interposition of a packing having a shape corresponding to the periphery 5.

In addition, a through hole 1 for supporting a measuring tube to be inserted is bored in the hollow part of the side part 6, and the periphery of this hole is thick. The periphery of the T protrudes flatly and is provided with a screw hole 8, which is used to properly connect the pipe to the measuring tube and to accommodate an O-ring that maintains the outer periphery of the measuring tube watertight. It serves as a mounting base part 9 for attaching the connection part.

On the other hand, from the inside of the side surface part 6, a support part 10 for supporting the core of the electromagnet protrudes toward the open surface side. It is formed by four parts 11.

In addition, through-holes 12 are drilled on all sides of the circumference 5 from the open surface side to the side surface 6 side, making it possible to use screws and making the circumference M5 symmetrical to each other. Protrusions 13a and 13b for positioning and corresponding fitting holes 14a and 14b are formed at these positions, respectively.

Therefore, two cases of the same shape configured as described above are prepared, and the protrusion 13a corresponds to the periphery 5.
, 13b and a through hole facing the fitting holes 14a, 14b are prepared, the open surfaces of each case are brought into contact with each other via this packing, and the protrusions 13a, 13b of one case are k Fitting hole 14b, 1 of the other case
4a, and the protrusion 13a of the other case.
, 13b into the fitting holes 14b and 14a of one case, and insert a screw into the through hole 17 to connect them.
The casing is sealed in a water-tight manner with a gasket and is completed as a single unit.

Figure 2 shows the state of assembly of the detector using the above-mentioned case. Figure (4) is a front view with the main parts cut away, and Figure (B) is a similar side view, with the two being formed to have the same shape. Case 101
The open surfaces of the tubes a and 101b are made to face each other, and are connected via a fitting 102 and connected by a screw 103 and a nut 104, and large connecting portions 105a are provided on both sides according to the inner diameter of the pipe to be connected. , 105b is Patsukin 106
, 107 and are fixed in a watertight manner with screws 108.

In addition, the outer iron core 110 having magnetic poles 109a and 109b facing each other includes coils 111a+111b.
are wound, and these constitute an electromagnet 112. A measuring tube 113 is inserted between the magnetic poles 109a and 109b, and both ends of this protrude into the connecting portions 105a and 105b. An electromagnet 112 is located in the portion held between the magnetic poles 109a and 109b.
Electrodes 114 are provided facing each other in a direction perpendicular to the direction in which the magnetic flux generated by the magnetic flux flows and along the central axis of liquid circulation, and are led out by screws 115, and lead wires 116a, 116b, each is pulled out from an outlet 117 provided above the cases 101a and 101b.

In addition, in FIG. 2(B), the lead wires 1'16a+ and 116a2 from the left electrode 114, which are omitted in the figure, are
is the magnetic pole 1 formed along the circumferential direction of the measuring tube 113
They are led symmetrically to the right through the grooves 118a and 118b of 09a and 109b, and are commonly connected to the lead wire 116a, thereby reducing the induced noise component caused by the magnetic flux.

The core 110 of the electromagnet 112 is attached to the support portion 10 protruding from the inner surface of the side surface of the case 101b with a screw 120.
The lead wire 116C for the common circuit which is fixed and derived from the lead wire 116C from each electrode 114 is the lead wire 116a from each electrode 114.
, 116b are drawn out from the outlet 117, while the coil 111a.

The lead wires 116d and 116e of the case 111b are also drawn out in the same way, and the inside of the case 1 (Ha, 101b) is filled with an insulating filler 121.

In addition, the measuring tube 113 is inserted closely into the outer tube 201, which is made of a straight metal tube having a predetermined mechanical strength as well as non-magnetic material such as stainless steel, and has a working flow fit range. The inner tube 202 is made of an insulating material and has an internal cross-sectional area corresponding to the inner tube 20.
2 is determined as a dimension that protrudes from both ends of the outer tube 201, and both ends of the inner tube 202 extend further into the enlarged step portions 122a and 122b formed inside the connecting portions 105a and 105b than both ends of the outer tube 201. After protruding and abutting,
O-ring 1 fitted as a seal ring to the outer circumference of this
Watertightness is maintained by 23a and 123b, and the connection part 105
a.

This is to prevent liquid from seeping into areas other than 105h and inner tube 202.

In addition, the outer tube 201 has magnetic poles 109a and 109b.
Through-holes 203 for leading out the electrodes are formed in mutually opposing parts of the inner tube 202, and the through-holes 203 of the inner tube 202
Attachment holes 204 for the electrodes 114 are formed in locations corresponding to the electrodes 114, through which the electrodes 114 are attached.

In addition, a pipe-shaped connection part provided on the converter to which the lead wire 116a=e is connected is fitted into the connection part 2 from the outer circumference, and two setscrews screwed into this are inserted into the tapered part 3. The tip of the connector 105 is pressed, thereby ensuring the connection between the detector and the converter.
Male threads 124a and 124b are cut in the holes 105b and 105b, making them suitable for threaded connection with piping.

In addition, the entire assembly consists of combining the electromagnet 112 and the measuring tube 113, attaching it to the case 101b, and screwing the
After fixing these with the screws 103 and nuts 104, the case 101a is attached through the gasket 102, and the gaskets 106 and 107 are connected.
and connection portion 105a.

105b, which naturally regulates the mutual relationship between the parts and facilitates assembly.

3 and 4 are detailed views of the inner tube 202, in which (2) is a front view, Φ) is a vertical cross-sectional view, (C) is a horizontal cross-sectional view, and 0 is an X-Y cross-sectional view at the plow. In the cross-sectional view, the one in Figure 3 is used when the inner diameter of the connected pipe line is nominally 25φ, and the one in Figure 4 is used when the same inner diameter is nominally 40φ.
In order to optimize the flow rate used and the flow velocity in the measurement pipe, a constriction part 205 with a small inner diameter is formed inside, and the internal cross-sectional area is determined by the range of flow rate used depending on the inner diameter of the connected pipe line. It becomes.

The mounting holes 204 are made up of through-holes 206 that are individually provided in the outer walls facing each other on the diameter line, and square-shaped accommodation holes 207 that are formed outwardly with a larger inner diameter. As described later, each member constituting the electrode 114 is inserted.

Note that the axial portion including the through hole 206 is formed with a flat portion 20B for convenience of molding, and in FIG. 3, the flange 209 is
are formed on the outer surface, and their outer peripheries are in close contact with the inner surface of the outer tube 201 to transmit radial liquid pressure to the outer tube 201 and improve pressure resistance.

5 is an enlarged cross-sectional view of the electrode 114. (5) uses the inner tube 202 of FIG. 3, and @) uses the inner tube 202 of FIG. 4. During assembly, the inner tube 202 is used. After inserting the O-ring 211 into the mounting hole 204 of the
The angular 7279 part 214 is exposed to the inside of the 02 and is accommodated in the accommodation hole 207 via the 0 ring 211, and has a through hole 221 approximately in the center.
In addition, when a spacer 222 made of an insulating material and having a height corresponding to the wall thickness of the inner tube 202 is inserted to the outside of the flange portion 214, the outer surface of the spacer 222 almost coincides with the outer circumferential surface of the inner tube 202. Become.

In this state, insert the inner tube 202 into the outer tube 201, align the mounting hole 204 with the through hole 203 of the outer tube 201, and insert the bushing part 232 of the bushing 231 made of insulating material into the through hole 203. protrude and outer tube 2
A contact portion 233 having a shape corresponding to the outer peripheral surface of 01 is attached to the outer tube 2.
01, the periphery of the outer circumferential surface of the through hole 203 is covered by the contact portion 233, and the bush 2
The mounting direction of 31 is automatically regulated.

Next, a set screw 115 whose length corresponds to the wall thickness of the inner tube 202 is
'e, If the bushing 231 is penetrated from the through hole 234 including the bushing part 232 to the electrode chip 212 and then screwed into the screw hole 215 of the electrode chip 212, the whole is completely fixed. 0 ring 211
This ensures watertightness.

Note that when inserting the screw 115, the lug terminals 241a, 2
41b 'Jk If inserted, guide grooves 235a and 235b for lead wires along the circumferential direction of bushing 2310
The ends of the lug terminals 241a and 241b are inserted into the terminal, and their directions are regulated and fixed, as shown in FIG. 2(B).
It is suitable for connecting the lead wires 116a1 and 116a2 shown in FIG. 1, and also for connecting the lead wire 116b shown in FIG.

The assembly of the measuring tube 113 is completed by the above, but then,
When the skirt portion 252 of the supporter 251 made of an insulating material is fitted from the outside of the bushing 231 along the axial direction of the set screw 115, the protruding portion 253 of the supporter 251 is fitted.
protrudes in a direction opposite to the bushing 231 in alignment with the axis of the set screw 115.

Therefore, the outer side portion 301 of the core 110 is divided approximately from the center, and the protrusion 25 is formed at the center of the outer side portion 301.
A notch 302 having a shape corresponding to that of measurement tube 1 is formed.
13 and the magnetic poles 109a and 109b facing each other, the protrusion 253 of the supporter 251 is accommodated and supported by the notch 302, and at the same time,
Since the outer surface portion 254 of the supporter 251 substantially coincides with the inner surface of the outer side portion 301, the mounting position and mounting angle of the measurement tube 113 are regulated, and the protrusion portion 253 is housed in a direction perpendicular to the magnetic flux passing through the measurement tube 113. As a result, the relative angle of the electrode tip 212 to the magnetic flux is also the same.

Note that the lead wire 11 (iax +
The lead wires 116az are wired through the notches 255a and 255b provided in the circumferential direction of the supporter 251, and the lead wires 116a and 116b are wired through the through hole 256 in the protrusion 253 and the notch 302 of the core 110. derived through.

FIG. 6 is a detailed view showing the electrode tip 212, and FIGS. 7 and 8 are detailed views showing the spacer 222. In each case, (2) is a front view, and (6) is a side cross section. The distal end portion 213 is formed into a planar shape, and the periphery of this is a cylindrical shape that fits the through hole 206 of the inner tube 202, and an angular 7-rank portion 214 is formed on the rear end side. After fitting with the accommodation hole 207 of the inner tube 202, the 7 rank part 21
When the set screw 115 is screwed into the screw hole 215 drilled on the 4th side, it exhibits a rotation-stopping effect.

In addition, in FIGS. 7 and 8, the spacer 222
is formed into an angular shape corresponding to the accommodation hole 207 of the inner tube 202, and a through hole 221 is bored in the center of the tube.
An outer surface portion 223 that coincides with the outer circumferential surface of the inner diameter 202 is
It is formed as the same curved surface as the outer peripheral surface of the inner tube 202, and the overall height h is determined according to the wall thickness of the inner tube 202.
The one with height h2 is shown in Figure 5 (4), and the one with height h2 is shown in Figure 5 (6).
) is m1.

Figure 9 shows the bushing 231 and Figure 10 shows the supporter 251.
(4) is a front view, Φ) is a side view, and Φ) is a cross-sectional view. A contact portion 233 is formed as a curved surface that is the same as the outer circumferential surface of the tube 201 , and protrudes downward from approximately the center of the contact portion 233 to meet the through hole 203 of the outer tube 201 .
A bushing portion 232 is formed to fit with the bushing portion 232.

゛Also, a through hole 234 is formed including the bushing portion 232, and the outer tube 2 defined by the abutting portion 233
01, guide grooves 235a and 235b are formed symmetrically with the through hole 234 as the center.

In FIG. 10, the skirt portion 2 is formed entirely in a cap shape and has an inner diameter corresponding to the outer diameter of the pusher 5.231.
52 is formed, and a portion 257 facing the outer tube 201 is formed as a curved surface that is the same as the outer peripheral surface of the outer tube 201.
Notches 255 m, 255 symmetrically along the circumferential direction of
b is formed.

Further, at the center of the outer surface portion 254 connected to the skirt portion 252, a rectangular tubular protrusion portion 253 having a through hole 256 is provided.
It is formed to correspond to the facing portion 257 and to match the i-radial line of the outer tube 201.

Therefore, by using the cases 10'la and 101b of the same shape, it is possible to reduce the cost and the number of machining steps required for the gui-casting type, etc., and it is also possible to easily reduce the cost due to the mass production effect, and to assemble the detector. This makes it easy to reduce the number of assembly steps, and also reduces the number of connections 105a for piping.
, IQ5b facilitates connection to small-diameter piping and reduces the cost of installation work.

The electrode 114 and the measuring tube 113 can be obtained with a simple and inexpensive structure, and can be easily combined with the electromagnet 112, so that each member can be arranged in a predetermined order.
If the inner pipe 202 and the connecting parts 105a, 105b, etc. are changed, it can be adapted to g-paths with various inner diameters, making it very easy to use. Many parts are shared, making it easy to reduce costs through mass production.

Of course, the shape shown in FIG. 1 can be arbitrarily selected according to the situation, and the connecting part 2 may be shaped like a half-width cylinder, etc., and the supporting part 1
0 may be extended from the side wall to form a step-like shape, or the connecting portion 2 may be omitted and wiring may be performed between the converter and the converter separately provided. Instead of being columnar, the fitting holes 14a and 14b may be shaped like a prism or a protrusion, and the shapes of the fitting holes 14a and 14b may be determined accordingly.
Instead of the projections 13a and 13b, positioning pins or the like may be inserted into the holes.

Furthermore, the outer tube 201 and the inner tube 202 may not be circular tubes, but may have other cross-sectional shapes, or may be curved tubes. The same effect can be obtained even if a rotation-stopping effect is obtained.The protrusion 253 of the supporter 251 may be a mere protrusion, and the shape of the notch 302 provided in the core 110 may be determined accordingly. Various modifications are possible, such as being buried during molding.

[Effects of the Invention] 6 As is clear from the above explanation, 9 according to the present invention, a measuring tube that does not require lining can be obtained, and if each part is assembled in a predetermined order, the interrelationships of each part are naturally regulated and assembly is easy. In addition to making it easier to use, each part can be shared, making it easier to reduce costs through mass production.It also makes it easier to connect to small-diameter snowy roads, and has a remarkable effect on electromagnetic flowmeters for various uses. is obtained.

[Brief explanation of drawings]

The figure shows an embodiment of the present invention, and FIG. 1 shows a case.
A) is a front view, (B) is a vertical sectional view, (c) is a rear view, 0
Fig. 2 shows the assembled state of the detector, (5) is a front view with the main parts cut away, ω) is a similar side view, Figs. 3 and 4 show details of the inner tube, ( A) Linear pressure surface view, (I3) is a vertical sectional view, (0 is a horizontal sectional view, (2) is an X-Y sectional view in (C), Figure 5 is an enlarged sectional view of the electrode, and Figure 6 is the electrode 7 and 8 are detailed views of the spacer, FIG. 9 is a detailed view of the bushing, and FIG. 10 is a detailed view of the supporter. 1... Box-shaped body, 2. ... Connecting part, 3... Tapered part, 5... Surroundings, 6 Fist... Side part, 7...
Through hole, 10...Support part, 13a, 13b---"Protrusion, 14a, 14b...Fitting hole, 101a, 10
1b m m ・m case, 102 ...packet, 103 ...screw, 104 ・war...nut, 1
05a, 105b ... Leopard connection part, 109a, 10
9b...Magnetic pole, 110---:Fa, 111a
, 111b @ e * * Coil, 112 --- Electromagnet, 113 --- Measuring tube, 114 --- Electrode, 115 ---, --- Right screw, 122 a , 122 b
...Enlarged stepped section, 123a, 123b...No.
0 ring, 201... outer tube, 202... inner tube. Patent applicant Yamatake Honeywell Co., Ltd. Agent Masaki Yamakawa (and 1 other person) Figure 1 (A) (B) Figure 1 ((j (D) Figure 6 (A) (B) Figure 7 (A') (B) ) Figure 8 (A) (B) Figure 9 (A) (B) 1. Indication of the incident 1982 Patent Application No. 128861 2. Name of the invention Detector for electromagnetic flowmeter 3. Person making the amendment Relationship to the case Patent Applicant name (name) (666) Yamatake Honeywell Co., Ltd. 5,
Target of correction tll Add “having a circular portion on the bottom side” next to “formed” on page 11, line 10 of the specification. (2) "0 ring 211..." on page 12, line 7 of the same book
"Into accommodation hole 207" in lines 8 to 8 is corrected as follows. [To fit the O-ring 211 into the circular part of the accommodation hole 2010, contact the stepped part with the circular part in the accommodation hole 201 and insert it into the accommodation hole 207.'' (3) Refer to Figure 2 (B) in the attached sheet. Tooshi correction. that's all

Claims (1)

[Claims] An outer tube made of a non-magnetic tubular body, and an insulating material inserted into the outer tube and having electrodes on mutually opposing inner wall surfaces, and having both ends protruding from both ends of the outer tube. A measuring tube consisting of the inner tube used, and a box-like body with an open side on the side, with a through hole for supporting the measuring tube on the side surface. a casing formed by inserting the end of the measuring tube through the casing and bringing the open surfaces into contact with each other, and each through hole of each case having an enlarged step portion therein against which the end of the inner tube abuts. The tube is characterized by comprising connecting portions for connecting pipes individually fixed to the outer surface, and seal rings that protrude from both ends of the outer tube and fit into both ends of the inner tube from the outer circumference. Detector for electromagnetic flowmeter.