JPS5858415A - Production for signal transmitter of electromagnetic flowmeter - Google Patents

Abstract

PURPOSE:To prevent the generation of foam and pinholes in a liquid insulating material and to maintain stable insulation characteristics for a long period of time by charging the insulating material into the spacing between a cylindrical case and a sleeve of the same shape as that of said case therein and hardening the material. CONSTITUTION:Iron cores 12 and exciting coils 13 are disposed in a case 11, following to which a sleeve 16 having a hole 16a on the circumferential surface is inserted into the case 11. An insulating material 18 which is liquid while not in reaction is charged into a space 17 through the hole 16a. Centrifugal forces are applied to the material 18 by rotating the case 11, thereby hardening said material.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing an electromagnetic flow pointer transmitter, and is intended to ensure that an insulating material for insulating an iron core, an excitation coil, etc. is stable over a long period of time and maintains nine characteristics.

FIG. 1 is a longitudinal sectional view showing an electromagnetic flow needle transmitter obtained by the prior art. As shown in the figure, this electromagnetic flow needle transmitter has a ring-shaped protrusion 1 a e that protrudes inward.
l b f Attach the iron core 2 and excitation coil 3 to the inner peripheral surface of the cylindrical case 1 at both ends with screws, etc., and attach the leads Ii for the electrodes 4! After wiring the iFs, a metallic or non-metallic sleeve 6 is inserted into the case 1, and both ends of the sleeve 60 are arc welded to the protrusions 1a and lb.

A space 7 is formed between the inner circumferential surface of the case 1 and the outer circumferential surface of the sleeve 6 by joining them with adhesive, screws, packing, or the like. After forming the space 7Yr in this way, the space 7 is filled with a solid, liquid, or gas insulating material 8 through the hole 1c formed on the circumferential surface of the case l, and then the A 1 ct hole is closed with a plug 9 and then lined with a lining 10. At this time, the filling of the insulating material 8 is performed by fixing the case 1 and injecting the insulating material 8 into the space 7 through the hole 1e. This is done by processing and hardening.

Therefore, the electromagnetic flow needle transmitter according to the prior art has the following drawbacks.

b) Air bubbles, pinholes, etc. are likely to occur in the insulating material 8, and in this case, when moisture enters from the joint between the case 1 and the sleeve 6, the excitation coil 3 may become flooded.

From the original purpose of the insulating material 80, which is to insulate the excitation coil 3, it is sufficient to fill the insulating material 8t only in the vicinity of the excitation coil 3, but the insulating material 1s#i is filled from the inside of the space 7. As a result, the amount of insulating material 8 that must be filled into the entire space 7 increases, and as a result, the cost of the electromagnetic flow needle transmitter increases and the total weight increases. At this time, if the outer diameter of the sleeve 6 is increased until it approaches the excitation coil 3, the volume of the space 7 can be reduced and the amount of insulation material 8 can be saved by 1tt. This means that 3 and lining 10 are close to each other, and since chloroglene rubber, polyurethane rubber, or the like, which is relatively easily deteriorated by heat, is used as the material for lining 10, there are restrictions in this respect.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, an object of the present invention is to provide a method for manufacturing an electromagnetic flow pointer transmitter that does not generate bubbles or pinholes in the insulating material and can simultaneously adjust the filling amount of the insulating material.

The structure of the present invention that achieves this object is to insert a cylindrical sleeve with a larger diameter into a cylindrical case, and to fix both ends of the sleeve to both ends of the case, so that the case and the sleeve can be connected to each other. In the method for manufacturing an electromagnetic flow pointer transmitter in which an iron core and an excitation coil are housed in a space between them, the iron core is housed in the case.

a step of arranging an excitation coil and an electric current of 1 fMt; a step of inserting a sleeve into the case and fixing both ends of the sleeve to both ends of the case; An insulating material that is liquid when unreacted is injected into the space formed between the inner peripheral surface and the space housing the iron core and excitation coil, and the case is rotated to apply centrifugal force. The present invention is characterized in that it further includes a process chart for curing the insulating material.

Embodiments of the present invention will be described in detail below based on the drawings.

As shown in FIG. 2, first, the iron core 12 and the excitation coil 13 are arranged in the case 1IP3, and then the sleeve 16 having holes 16ai on the circumferential surface is inserted into the case 11, and both ends of the sleeve 16 and the case 11 are inserted into the case 11. The protrusion 11a, 1lbt-
Join them respectively.

As a result, the iron core 12 and the excitation coil 13 are connected to the cable 11.
The sleeve 16 is housed in a space 17 formed between the inner peripheral surface of the sleeve 16 and the outer peripheral surface of the sleeve 16. Subsequently, an insulating material 18t-, which acts as a contact body when there is no reaction, is inserted through the hole 16a.
The insulating material 18 is injected into the space 17, turned around the case 1lt, and applied centrifugal force to harden the insulating material 18. The amount of insulating material 18 filled at this time can be adjusted as appropriate.

That is, as shown in FIG.
The minimum necessary amount of lids may be filled and the remaining portions may be left in 11 of the spaces 17, or the entire spaces 17 may be filled. When the required minimum amount is filled, the amount of line supply edge material 18 can be reduced and the overall weight can be reduced.

After the insulating material 18 is cured in this way, the hole 16at
- Close it with a stopper 19 and line it with a lining 2o. In addition, in FIG. 2, the x4Fi electrode and 15 are lead wires. Further, in the embodiment described above, the sleeve IIC hole 16a is formed, and the insulating material 18'j- is injected through the hole 16a.As shown in FIG.
1 (1), and the insulating material 18 may be injected through the holes 11a and 11 (1).

FIG. 4 shows embodiment #I2 of the present invention. In this example, the insulating material 18t is cured while rotating the case 11, and then the sleeve 16t is inserted into the case 11, and then both ends of the sleeve 16 and the protrusions 11a and 11 of the case 11 are inserted.
Join b with adhesive or welding. That is, in this embodiment, the order of the step of hardening the insulating material 18 and the step of inserting the sleeve 111I into the case 11 is opposite to that of the embodiment shown in FIGS. 2 and 3. In addition, when joining by welding, as shown in FIG. Material 18
Even if the insulating material 18 is easily thermally decomposed such as epoxy resin, the insulating material 18 will not deteriorate due to the heat of welding.

As specifically explained above in conjunction with the embodiments, according to the present invention, there is a space between the outer circumferential surface of the sleeve and the inner circumferential surface of the case, which has a shape of tL, and accommodates 11 iron cores and excitation coils. An insulating material that is liquid when unreacted is placed in a space by a madman, and the case is rotated to harden the insulating material while applying centrifugal force, resulting in bubbles, pinholes, etc. in the insulating material. Therefore, even if moisture infiltrates from the joint between the sleeve and the case, safe insulation properties can be maintained for a long period of time. Also, since the filling amount of the insulating material can be adjusted, the filling amount can be maintained optimally.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an electromagnetic flow pointer transmitter obtained by the method of the prior art, and FIGS. 2 and 3 are longitudinal cross sections showing an electromagnetic flow pointer transmitter obtained by the first embodiment of the present invention. FIG. 4 and FIG. 5 are explanatory diagrams for fully explaining the second embodiment of the present invention. In the drawing, 1, lit! Case, 2.12 Mineral iron core, 3.13 Excitation coil, 4.14e′i electrode, 6.16Fi sleeve, 7.17#i space, 8.15#i insulation material. Representative of Kitamaro Electric Seisakusho Co., Ltd. Patent Attorney Shibe Mitsuishi (and 1 other person) Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A cylindrical sleeve with a smaller diameter is inserted into the cylindrical case, and both ends of this sleeve are fixed to both ends of the case, and an iron core and an excitation coil A are placed in the space between the case and the sleeve. A method for manufacturing an electromagnetic flow positioning needle transmitter O1l in which the electromagnetic flow needle transmitter is housed includes a step of arranging an iron core, an excitation coil, and an electrode in the case, and inserting a sleeve into the case and connecting both ends of the sleeve to both ends of the case. the space formed between the outer circumferential surface of the sleeve and the inner circumferential surface of the case, and which houses the iron core and the excitation coil, is filled with liquid when unreacted. 1. A method for producing an electromagnetic flow pointer transmitter, comprising: injecting a certain amount of insulation material, rotating the case, and hardening the insulation material while applying centrifugal force.