JP2540250B2 - Manufacturing method of terminal pin for welded joint - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a terminal pin used in a welding joint.

[0002]

It is generally known to use a welded joint when joining pipes made of a thermoplastic resin such as polyethylene to each other. In this welding joint, the joint body is formed of a thermoplastic resin, the conductive wire is embedded in the inner peripheral portion of the joint body, and the pair of terminal pins connected to the conductive wire is provided on the outer peripheral portion of the joint body. . When using the above welding joint, pipes are inserted into both ends of the joint body, and a constant voltage is applied between the terminal pins to conduct electricity. Then, the heat generated by the conductive wire melts the surrounding resin, and the welding joint and the pipe are welded to each other.

By the way, the structure of the terminal pin of the welding joint is described in Japanese Patent Laid-Open No. 2-129493. This conventional terminal pin includes a main contact pin having a tubular portion, a resistor provided inside the tubular portion, and an auxiliary contact pin provided on the resistor. An insulator is provided between the contact pin and the resistor and between the auxiliary contact pin and the resistor. Also,
The upper end of the resistor is connected to the auxiliary contact pin via a lead wire, and the lower end of the resistor is connected to the main contact pin via a lead wire. Therefore, when connecting the terminal pin to the connector on the controller side, the first contact of the connector is brought into contact with the main contact pin and the second contact of the connector is brought into contact with the auxiliary contact pin. Then, a current flows through the conductive wire of the welding joint for a time set based on the resistance value of the resistor, and the conductive wire is heated.

[0004]

Since the above-mentioned conventional terminal pin uses two contact pins, the material cost becomes high. In addition, at the time of manufacturing, a step of connecting the resistor and the main contact pin and a step of connecting the resistor and the auxiliary contact pin are necessary, and since these connections are made through the lead wire, the manufacturing efficiency is improved. Is bad. Further, the caulking work is required for the connection via the lead wire, but the caulking work is likely to cause variations due to the skill level of the operator, so that there is a problem that a connection failure is likely to occur.

Further, in the above-mentioned conventional terminal pin, since the resin is filled between the main contact pin and the resistor to form the insulator, the resistor is pressed by the resin pressure while the resin is being filled. There is a problem in that it is easy to move and the side portion of the resistor comes into contact with the main contact pin, so that insulation failure is likely to occur. If a poorly-insulated terminal pin is used in the welding joint, the time during which the current flows through the conductive wire changes, and the resin around the conductive wire is overheated or underheated.

In view of the above-mentioned problems of the prior art, the present invention aims to provide a method of manufacturing a terminal pin which can improve the manufacturing efficiency and can reduce connection failure and insulation failure. I am trying.

[0007]

In order to achieve the above object, in the present invention according to claim 1, an insulator having a through hole is provided inside a tubular portion formed on a contact pin. A method of manufacturing a method in which a resistor is pierced through a through hole of an insulator after being fixed in a direction in which the depth direction of the grooved portion and the axial direction of the through hole are aligned, and the resistor is penetrated when the resistor is pierced. The lower end of the contact was brought into contact with the contact pin to connect the resistor and the contact pin.

Further, according to the present invention as set forth in claim 2, the insulator, which penetrates the resistor, is provided inside the tubular portion formed on the contact pin and in the depth direction of the tubular portion and the resistor. The manufacturing method is such that the resistors are fixed in a direction that coincides with the axial direction, and when the insulator is fixed, the lower end portion of the resistor is brought into contact with the contact pin to connect the resistor and the contact pin.

[0009]

According to the first aspect of the present invention, when the resistor is penetrated, the lower end of the resistor is brought into contact with the contact pin to connect the resistor and the contact pin. It is possible to connect the resistor and the contact pin without requiring any technique, and it is possible for the unskilled person to reliably connect the resistor and the contact pin.

Further, the insulator having the through hole is fixed inside the tubular portion formed on the contact pin in a direction in which the depth direction of the tubular portion and the axial direction of the through hole coincide with each other. After that, since the resistor is penetrated through the through hole of the insulator, the insulator can be reliably interposed between the resistor and the contact pin, and the resistor and the contact pin can be reliably insulated.

According to the second aspect of the present invention, since the lower end of the resistor is brought into contact with the contact pin to connect the resistor and the contact pin when the insulator is fixed, a high degree of caulking work or the like is required. It is possible to connect the resistor and the contact pin without requiring any technique, and it is possible for the unskilled person to reliably connect the resistor and the contact pin.

Further, the insulator penetrating the resistor is fixed inside the tubular portion formed on the contact pin in a direction in which the depth direction of the tubular portion and the axial direction of the resistor coincide with each other. With this method, an insulator can be reliably interposed between the resistor and the contact pin, and the resistor and the contact pin can be reliably insulated.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. First, the structure of the three types of terminal pins P1, P2, P3 will be described with reference to FIGS. 1a in the figure,
1b and 1c are contact pins, 2a, 2b and 2c are insulators, 3
Reference characters a, 3b, 3c are resistors, and these terminal pins P1, P2, P3 are cylindrical portions 11a, 11b, 11c formed at the upper ends of the contact pins 1a, 1b, 1c.
The insulators 2a, 2b, 2c are fixed by screwing to the inside of the insulator.
The configuration is common in that a, 3b, and 3c are provided so as to penetrate therethrough. The contact pins 1a, 2b, 3c may be made of metal other than gun metal such as gun metal, stainless steel, copper or aluminum, or may be made of conductive plastic. In addition, the resistors 3a, 3
It is preferable that b and 3c have a metal film formed on their surface by solder plating or the like, and that the surface is difficult to oxidize,
The insulators 2a, 2b, 2c are made of polyacetal,
It is possible to use a synthetic resin having a high insulating property such as polypropylene, polyethylene, or polyvinyl chloride.

Next, each terminal pin P1, P2, P3
First, in the terminal pin P1 shown in FIG. 1, the insulator 2a is the cylindrical portion 11 of the contact pin 1a.
It is formed to have a length almost twice as long as a, and the upper half of the insulator 2a projects above the contact pin 1a. Further, the resistor 3a is formed to be slightly longer than the length of the insulator 2a, the upper end of the resistor 3a projects from the upper end surface of the insulator 2a, and the lower end of the resistor 3a has the insulator 2a.
Protruding from the lower end surface of.

In the terminal pin P2 shown in FIG. 2, the insulator 2b is formed to have substantially the same length as the cylindrical portion 11b of the contact pin 1b, and the upper end surfaces of the resistor 3b and the insulator 2b are the contact pin 1b. It is flush with the top surface of the. Further, the resistor 3b is formed to be slightly longer than the length of the insulator 2b, the upper end of the resistor 3b is flush with the upper end face of the insulator 2b, and the lower end of the resistor 3b is It projects from the lower end surface of the insulator 2b. Further, the contact pin 1b has a conductive wire 4 connected to the lower end surface of the resistor 3b.
b is buried.

In the terminal pin P3 shown in FIG. 3, the insulator 2c has the cylindrical portion 11c of the large diameter portion 23c having the same thickness as the cylindrical portion 11c of the contact pin 1c and the cylindrical portion 11c of the contact pin 1c. And a small diameter portion 24c thinner than the insulator 2
The small-diameter portion 24c of c is formed to have substantially the same length as the cylindrical portion 11c of the contact pin 1c, and the insulator 2c has a large-diameter portion 23c protruding above the contact pin 1c. Also,
The resistor 3c is formed to have substantially the same length as the insulator 2c, the upper end of the resistor 3c is flush with the upper end surface of the insulator 2c, and the lower end of the resistor 3c is the insulator. It is flush with the lower end surface of 2c.

Next, the terminal pins P1, P2, P
A first embodiment of the manufacturing method of No. 3 will be described. Incidentally, FIG. 4 shows a method of manufacturing the terminal pin P1.

(A) First, as shown in (a) of FIG. 4, the insulator 2a having the through hole 21a formed in the central portion and the screw thread 22a formed on the outer peripheral surface of the lower half is connected to the contact point. The pin 1a is molded to have a length twice that of the tubular portion 11a. The insulator 2a may be formed by cutting a cylindrical extruded product into an appropriate length and then cutting the thread 22a on the outer peripheral surface of the lower half of each extruded product. After cutting the extruded product into an appropriate length, the screw thread 22a may be cut on the outer peripheral surface of the lower half of each extruded product, and the through hole 21a may be formed in the center of each extruded product. Good. At this time, the through hole 21
From the viewpoint of water resistance and the like, it is preferable that a has a hole diameter equal to or slightly smaller than the outer diameter of the resistor 3a.
Expressing the allowable range numerically, the outer diameter of the resistor 3a + 0.
It is about 00 mm to −0.05 mm. Further, the screw thread 22a is preferably formed in a trapezoidal shape, but the shape is not particularly limited.

(B) Next, as shown in (b) of FIG. 4, the insulator 2a is placed inside the tubular portion 11a formed on the contact pin 1a and the depth direction of the tubular portion 11a is changed. Through hole 2
It is fixed by screwing in a direction in which the axial direction of 1a coincides. Since the insulator 2a is formed to have a length twice that of the tubular portion 11a of the contact pin 1a, the upper half portion projects above the contact pin 1a. In addition, it is necessary to previously cut a screw thread 12a inside the cylindrical portion 11a of the contact pin 1a.

(C) Next, as shown in FIG. 4 (c), the resistor 3a having a longer length than the insulator 2a is connected to the insulator 2a.
It is press-fitted into the through hole 21a of "a" so that it penetrates. At this time, the lower end portion of the resistor 3a is projected from the lower end surface of the insulator 2a and brought into contact with the bottom surface of the cylindrical portion 11c of the contact pin 1a to connect the resistor 3a and the contact pin 1a. If the surface of the resistor 3a is coated with a lubricating material, the resistor 3a can be easily inserted into the through hole 21.
It can be pressed into a. When the lower end of the resistor 3a is projected from the lower end surface of the insulator 2a, the resistor 3a
Before the lower end surface of a contacts the contact pin 1a, the resistor 3a
The outer peripheral surface of the lower end of the contact pin contacts the inner peripheral surface of the tubular portion 11a of the contact pin 1a. Therefore, even if the resistor 3a is not press-fitted enough and the lower end surface of the resistor 3a and the bottom surface of the tubular portion 11a are not in contact with each other, the outer peripheral surface of the lower end portion of the resistor 3a and the tubular portion 1 are connected.
If the inner peripheral surface of 1a is in contact, the resistor 3a and the contact pin 1a are in a connected state.

The terminal pin P1 can be manufactured by the steps (a), (b) and (c) described above.

When manufacturing the terminal pin P2, the insulator 2b is replaced with the contact pin 1b in the step (a).
The cylindrical portion 11b is formed to have almost the same length, and the thread 22b is formed on the entire outer peripheral surface of the insulator 2b. Further, in the step (b), the entire insulator 2b is fixed to the inside of the tubular portion 11b formed on the contact pin 1b by screwing. Then, since the insulator 2b is formed to have substantially the same length as the tubular portion 11b of the contact pin 1b, the upper end surface of the insulator 2b and the upper end surface of the contact pin 1b are flush with each other. Further, in the step (c), a resistor 3b having a total length longer than that of the insulator 2b is used, and the resistor 3b is removed until the upper end of the resistor 3b is aligned with the upper end of the insulator 2b.
To be inserted into the through hole 21b by press fitting. At this time, the lower end portion of the resistor 3b protruding from the lower end surface of the insulator 2b is brought into contact with the bottom surface of the cylindrical portion 11b of the contact pin 1b and the conductive wire 4 embedded in the contact pin 1b to form the resistor 3b. The contact pin 1b is connected, and the resistor 3b and the conductive wire 4 are connected. In addition, the resistor 3b is connected to the through hole 21 of the insulator 2b.
When press-fitting into b, the lower end face of the resistor 3b and the contact pin 1b
If the conductive wire 4 is projected so that the lower end portion of the resistor 3b and the conductive wire 4 come into contact with each other before the bottom surface of the cylindrical portion 11b comes into contact, the resistor 3b cannot be press-fitted. Resistor 3b
Even if the lower end surface of the contact point and the contact pin 1b are not in contact with each other, the contact between the resistor 3b and the conductive wire 4 can connect the resistor 3b and the contact pin 1b.

When the terminal pin P3 is manufactured, in the step (a), the large diameter portion 23c having the same thickness as the contact pin 1c and the small diameter portion 2 thinner than the contact pin 1c.
4c, the small diameter portion 24c of the insulator 2c is formed to have substantially the same length as the cylindrical portion 11c of the contact pin 1c, and the thread 22c is formed on the outer peripheral surface of the small diameter portion 24c.
The insulator 2c in which is formed is molded. Further, in the step (b), the small-diameter portion 24c of the insulator is fixed to the inside of the cylindrical portion 11c formed on the contact pin 1c by screwing. Then, since the large diameter portion 23c of the insulator 2c is formed to have the same thickness as the cylindrical portion 11c of the contact pin 1c, the outer peripheral surface of the insulator 2c and the outer peripheral surface of the contact pin 1c are continuous surfaces, It is difficult for water to enter from the joint between the insulator 2c and the contact pin 1c, and the water resistance is enhanced. Furthermore (C)
In the step of, the resistor 3c whose total length is equal to the length of the insulator 2c is used, and the resistor 3c is pressed into the through hole 21c of the insulator 2c until the upper end of the resistor 3c is aligned with the upper end surface of the insulator 2c. The lower end surface of the resistor 3c, which is flush with the lower end surface of the insulator 2c, is brought into contact with the bottom surface of the cylindrical portion 11c of the contact pin 1c to connect the resistor 3c and the contact pin 1c.

As described above, according to the manufacturing method of the first embodiment, when the resistors 3a, 3b, 3c are penetrated through the through holes 21a, 21b, 21c of the insulators 2a, 2b, 2c, the resistor 3 is formed.
Since the lower ends of a, 3b, 3c are brought into contact with the contact pins 1a, 1b, 1c to connect the resistors 3a, 3b, 3c and the contact pins, it is not necessary to use an advanced technique such as caulking work. Since the resistors 3a, 3b, 3c and the contact pins can be connected to each other, the resistor 3 can be securely connected even by an unskilled person.
It is possible to connect a, 3b, 3c and the contact pin.

Further, the insulators 2a, 2b, 2c having the through holes 21a, 21b, 21c are connected to the contact pins 1a, 1b,
It is fixed inside the tubular portions 11a, 11b, 11c formed in 1c in a direction in which the depth direction of the tubular portions 11a, 11b, 11c and the axial direction of the through holes 21a, 21b, 21c match. Through the through holes 2 of the insulators 2a, 2b, 2c.
Since the resistors 3a, 3b, 3c are penetrated through the resistors 1a, 21b, 21c, the insulators 2a, 2b, 2 are surely provided between the resistors 3a, 3b, 3c and the contact pins 1a, 1b, 1c.
c can be interposed, and the resistors 3a, 3b,
3c and the contact pins 1a, 1b, 1c can be insulated.

That is, the connection failure between the resistors 3a, 3b, 3c and the contact pins 1a, 1b, 1c can be reduced, and the resistors 3a, 3b, 3c and the contact pins 1a, 1 can be reduced.
Since the insulation defects of b and 1c can be reduced, the number of defective products can be reduced, and the resistor 3a,
Since the work of connecting the contact pins 3a, 3b to the contact pins 1a, 1b, 1c is easy, the manufacturing efficiency can be improved. Further, as described above, the number of defective products can be reduced, and the manufacturing efficiency can be improved, so that the cost can be reduced.

Next, the terminal pins P1, P2, P
2nd Example of the manufacturing method of 3 is described. Note that FIG. 5 illustrates a method of manufacturing the terminal pin P2.

(A) First, as shown in (a) of FIG. 5, the contact pin 1 is provided with the insulator 2b which is penetrated by the resistor 3b and has the thread 22b formed on the entire outer peripheral surface thereof.
It is formed to have substantially the same length as the cylindrical portion 11b of b. The method is a method of press-fitting the resistor 3b into the through hole 21b of the insulator 2b after molding the insulator 2b having the through hole 21b formed in the central portion and the thread 22b formed on the entire outer peripheral surface. Alternatively, a method of molding the insulator 2b with an injection molding die in which the resistor 3b is inserted may be used. In either method, a resistor 3b that is longer than the insulator 2b is used, the upper end surface of the resistor 3b is flush with the upper end surface of the contact pin 1b, and the lower end surface of the resistor 3b is the contact pin 1b. Make it stick out from the bottom edge.

(B) Next, as shown in (b) of FIG. 5, the entire insulator 2b through which the resistor 3b penetrates is placed inside the tubular portion 11b formed on the contact pin 1b. The tubular portion 11b is fixed by screwing in a direction in which the depth direction of the tubular portion 11b and the axial direction of the resistor body 3b are coincident with each other, and the lower end portion of the resistor body 3b is brought into contact with the bottom surface of the tubular portion 11b of the contact pin 1b. Body 3
b is connected to the contact pin 1b, and the lower end of the resistor 3b is brought into contact with the conductive wire 4 embedded in the contact pin 1b to connect the resistor 3b and the conductive wire 4. Since the insulator 2b is formed to have substantially the same length as the cylindrical portion 11b of the contact pin 1b, the upper end surfaces of the insulator 2b and the resistor 3b and the upper end surface of the contact pin 1b are flush with each other. Contact pin 1b
It is necessary to previously cut the thread 12b inside the cylindrical portion 11b. Further, when the insulator 2b is screwed into the tubular portion 11b of the contact pin 1b, the resistor 3 is provided before the lower end surface of the resistor 3b and the bottom surface of the tubular portion 11b of the contact pin 1b come into contact with each other.
If the conductive wire 4 is made to project so that the lower end portion of b and the conductive wire 4 come into contact with each other, the lower end surface of the resistor 3b and the bottom surface of the tubular portion 11b will not be screwed with the insulator 2b. Even if they are not in contact with each other, the contact between the resistor 3b and the conductive wire 4 causes the resistor 3
b and the contact pin 1b can be connected.

The terminal pin P2 can be manufactured by the steps (a), (b) and (c) described above.

In the case of manufacturing the terminal pin P1, in the step (a), the insulator 2a is formed such that the resistor 3a penetrates and the screw thread 22a is formed on the outer peripheral surface of the lower half portion. Is formed to be twice as long as the cylindrical portion 11a of the contact pin 1a. Further, the resistor 3a is longer than the insulator 2a, and the upper end surface of the resistor 3a is projected from the upper end surface of the contact pin 1a, and the lower end surface of the resistor 3a is projected from the lower end surface of the contact pin 1a. . In the step (b), the lower end of the insulator 2a is fixed to the inside of the tubular portion 11a formed on the contact pin 1a by screwing. Then, the terminal pin P1 in which the upper half portion of the insulator 2a projects above the contact pin 1a can be manufactured. Further, the insulator 2a is connected to the tubular portion 11 of the contact pin 1a.
When screwed into a, the lower end outer surface of the resistor 3a and the contact pin 1a come into contact before the lower end surface of the resistor 3a comes into contact with the bottom surface of the tubular portion 11a of the contact pin 1a. Even if the lower end surface of the resistor 3a and the bottom surface of the tubular portion 11a of the contact pin 1a are not in contact with each other due to insufficient insulation of the insulator 2a, the outer peripheral surface of the lower end portion of the resistor 3a and the tube of the contact pin 1a Portion 11a
If the inner peripheral surface of the contact is in contact, the resistor 3a and the contact pin 1
A connection state is obtained with a.

When manufacturing the terminal pin P3, in the step (a), the cylindrical portion 1 of the contact pin 1c is manufactured.
A large diameter portion 23c having the same thickness as 1c and a tubular portion 11c of the contact pin 1c which is thinner than the tubular portion 11c of the contact pin 1c.
And a small diameter portion 24c having substantially the same length as that of the small diameter portion 2
Insulator 2 having threads 22c formed on the outer peripheral surface of 3c
Mold c. Further, the resistor 3c has the same length as the insulator 2c, and the upper end surface of the resistor 3c is connected to the contact pin 1
The lower end surface of the resistor 3c is flush with the upper end surface of the contact pin 1c, and the lower end surface of the resistor 3c is flush with the lower end surface of the contact pin 1c. In the step (b), the small diameter portion 23c of the insulator 2c is screwed and fixed to the inside of the cylindrical portion 11c formed on the contact pin 1c. Then, the large-diameter portion 2 of the insulator 2c
It is possible to manufacture the terminal pin P3 in which 3c projects above the contact pin 1c and the outer peripheral surface of the large diameter portion 23c and the outer peripheral surface of the contact pin 1c are continuous.

As described above, in the manufacturing method of the second embodiment,
When fixing the insulators 2a, 2b, 2c to the insides of the cylindrical portions 11a, 11b, 11c of the contact pins 1a, 1b, 1c, the lower end portions of the resistors 3a, 3b, 3c are contact pin 1a,
Since the resistor 3a, 3b, 3c and the contact pin 1a, 1b, 1c are brought into contact with the resistor 3a, 1b, 1c, the resistor 3a, 3b without the need for a high-level technique such as caulking work.
3b, 3c and the contact pins 1a, 1b, 1c can be connected, and even if it is not an expert, the resistors 3a, 3b,
3c and the contact pins 1a, 1b, 1c can be connected.

The insulators 2a, 2b and 2c, which penetrate the resistors 3a, 3b and 3c, are connected to the contact pins 1a, 1b and 1c.
A method of fixing to the inside of the tubular portions 11a, 11b, 11c formed in c in such a manner that the depth direction of the tubular portions 11a, 11b, 11c and the axial direction of the resistors 3a, 3b, 3c coincide with each other. Therefore, the insulators 2a, 2b, 2 are surely provided between the resistors 3a, 3b, 3c and the contact pins 1a, 1b, 1c.
c can be interposed, and the resistors 3a, 3b,
3c and the contact pins 1a, 1b, 1c can be insulated.

That is, the connection failure between the resistors 3a, 3b, 3c and the contact pins 1a, 1b, 1c can be reduced, and at the same time, the resistors 3a, 3b, 3c and the contact pins 1a, 1c.
Since the insulation defects of b and 1c can be reduced, the number of defective products can be reduced, and the resistor 3a,
Since the work of connecting the contact pins 3a, 3b to the contact pins 1a, 1b, 1c is easy, the manufacturing efficiency can be improved. Further, as described above, the number of defective products can be reduced, and the manufacturing efficiency can be improved, so that the cost can be reduced.

The terminal pin P manufactured by the above method
1, P2, P3 are connected to a conductive wire embedded in an inner peripheral portion of a thermoplastic resin joint body (not shown) and to a controller-side connector having a first contact and a second contact. Connected. That is, the connection with the conductive wire is made at the lower end of the contact pins 1a, 1b, 1c, and the connection with the connector is the contact pins 1a, 1b, 1c for the first contact.
The cylindrical portions 11a, 11b, 11c are used for the second contact, and the upper ends of the resistors 3a, 3b, 3c are used for the second contact. Then, the current can be passed through the conductive wire for a time set based on the resistance values of the resistors 3a, 3b, 3c. As described above, the terminal pin P of this embodiment is
1, P2, P3 connect the contact points of the connector to the upper end surfaces of the resistors 3a, 3b, 3c.
Since the upper end surfaces of 3b and 3c are plated with solder, no contact failure occurs. Incidentally, as a concrete structure of the joint body and a concrete structure of the connector on the controller side, there are those shown in Japanese Patent Laid-Open No. 2-129493 mentioned in the prior art.

Although the embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and there are design changes and the like within a range not departing from the gist of the present invention. Also included in the present invention. For example, in order to improve water resistance between the contact pin and the insulator, a seal material may be interposed between the contact pin and the insulator, or a caulking material may be filled. Further, by slightly reducing the outer diameter of the insulator downward and correspondingly slightly expanding the tubular portion of the contact pin downward, screwing of the insulator and the contact pin can be easily started.

[0038]

As described above, in the manufacturing method according to the first and second aspects, the connection failure between the resistor and the contact pin can be reduced and the insulation failure between the resistor and the contact pin can be reduced. As a result, the number of defective products can be reduced. Moreover, since the work of connecting the resistor and the contact pin is easy, the manufacturing efficiency can be improved.

Further, as described above, the number of defective products can be reduced and the manufacturing efficiency can be improved, so that the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a terminal pin.

FIG. 2 is a vertical sectional view showing a terminal pin.

FIG. 3 is a vertical cross-sectional view showing a terminal pin.

FIG. 4 shows a method for manufacturing the terminal pin of the first embodiment, in which (a) is an explanatory view of a step of molding an insulator,
(B) is an explanatory view of the step of fixing the insulator to the contact pin,
(C) is explanatory drawing of the process of making a resistor penetrate an insulator.

5A and 5B show a method of manufacturing a terminal pin according to a second embodiment, wherein (A) is an explanatory view of a step of forming an insulator through which a resistor penetrates, and (B) fixes the insulator to a contact pin. It is explanatory drawing of the process to do.

[Explanation of symbols]

 P1 Terminal pin 1a Contact pin 11a Cylindrical part 2a Insulator 21a Through hole 3a Resistor

Claims (2)

(57) [Claims] 1. An insulator having a through hole is fixed inside a tubular portion formed on a contact pin in a direction in which the depth direction of the tubular portion and the axial direction of the through hole coincide with each other. After that, it is a manufacturing method of penetrating the resistor into the through hole of the insulator, wherein the lower end of the resistor is brought into contact with the contact pin to connect the resistor and the contact pin when penetrating the resistor. And a method for manufacturing a terminal pin for a welding joint. 2. An insulator, which penetrates the resistor, is fixed inside a tubular portion formed on the contact pin in a direction in which the depth direction of the tubular portion and the axial direction of the resistor coincide with each other. A method of manufacturing a terminal pin for a welding joint, characterized in that, when fixing the insulator, the lower end of the resistor is brought into contact with the contact pin to connect the resistor and the contact pin.