JPH0419925A - Truncated cone type electric contact - Google Patents

Abstract

PURPOSE:To prevent the outer circumference of a contact point from warping by making the contact surface area of a contact top part small and the ratio of the height to the contact surface area high and no edge in the circumference of the contact plane and forming a prescribed R in the middle of the upper side projected part and the lower side brim part of the outer circumference of a contact point. CONSTITUTION:On a truncated cone type electric contact point 10, step parts 11 are formed in the outer circumference of a top concentrically and the height (t) of the steps 11 is made to be at least 0.15mm and the outer diameter D1 of the upper side projected part 13 and the outer diameter D2 of the lower side brim part 14 is adjusted to have a relation D1<=D2-0.4mm. Since the lower side brim part warps up-ward if the lower side brim part 14 of the top 11 is too large against the leg part, the diameter (d) of the leg part 15 is adjusted to have a relation d<=D2-0.4mm. The R1 of the upper circumference of the upper side projected part 13 and the R3 of the upper circumference of the lower side brim part 14 are made to be >=0.1mm and R2 of a part ranging the lower end circumference of the upper side projected part 13 and the upper plane of the lower side brim part 14 is made to be >=0.15mm.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a base cylindrical electric contact that is attached to a spring base of a fixed contact or a movable contact such as a relay or a switch.

(Prior Art) Conventionally, as shown in FIG. 9, electric contacts attached to spring bases of fixed contacts and movable contacts such as relays and switches include base cylindrical electric contacts 2 having a low head 1. It is used.

(Problem to be Solved by the Invention) However, in recent years, as relays, switches, etc. have become smaller due to the miniaturization of electrical equipment, the fixed contact 3 and the movable contact 3' shown in FIG. electrical contact 5.5
The head height h of the electrical contact 5 is gradually decreasing.
．． The load on 5' is becoming high.

As described above, when the head height Fl of the electric contact 5.5' is low and the load becomes high, the outer peripheral side of the head warps upward due to the arc energy at the time of contact, as shown in Figure 1!

When this warpage becomes severe, the arc becomes concentrated and welding becomes easy.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a cylindrical base type electric contact in which the outer peripheral side of the contact does not warp upward.

(Means for Solving the Problems) A cylindrical tabletop electrical contact of the present invention for solving the above problems is a cylindrical tabletop electric contact having a head with a low height.
A stepped portion is provided concentrically on the outer periphery of the head, and the outer diameter of the upper convex portion is formed by the stepped portion and has a height t of 0.15 mm or more;
and the outer diameter D2 of the lower flange is D1≦D, -0.4mm
The leg diameter d is d≦D2−〇, 4 mm,
The radius R1 of the upper end periphery of the upper convex portion and the radius R8 of the upper end periphery of the lower flange are set to 0.1 mm or more, and the radius R2 of the portion extending from the lower end periphery of the upper bulge to the upper surface of the lower flange is 0. .15 mm or more.

In the tabletop cylindrical electric contact of the present invention, the outer diameter of the upper convex portion in the head and the outer diameter D2 of the lower collar portion are such that D1≦D,
The reason why it is set to -0.4 mm is that the radius R of the portion extending from the lower end peripheral edge of the upper convex part to the upper surface of the lower collar part is set to 0.4 mm.
15mm or more, R of the upper edge of the lower flange,
0. ] mm or more, and the radius R2 is 0.
The reason why the radius R3 is set to 15 mm is to prevent the head from springing up, and there is no effect if it is less than 0.15 mm.The reason why the radius R3 is set to 0.1 mm or more is to prevent the head from popping up. This is to prevent cracks from forming in the portion where the upper end periphery of the side flange is formed, and if it is less than 0.1 mm, there is no effect. Also, the leg diameter d is d≦D,
-0.4 mm is set because if the lower flange of the head is too large relative to the legs, the lower flange will warp. Furthermore, the height t of the upper convex part of the head is 0.15 m.
The radius R2 of the portion extending from the lower edge of the upper convex portion to the upper surface of the lower flange is 0.15 m or more.
This is to ensure that it is at least m.

(Function) The tabletop cylindrical electric contact of the present invention configured as described above has a small contact area at the contact head, a large height to contact area ratio (no etching on the periphery of the contact surface, and Since the contact head has a radius of 0.15 mm or more in the middle between the upper protrusion and the lower flange, even when the load is high, the outer circumference of the head is prevented from warping due to arc energy during contact.Also. Even if the lower flange warps slightly, there is no edge on the periphery of the contact surface, so the arc will not concentrate and welding will be prevented.

(Example) An example and a conventional example of the base cylindrical electric contact of the present invention will be described.

First, an embodiment will be explained with reference to FIGS. 1 and 2. FIG. 1 shows a base cylindrical electric contact 10 for fixed contacts such as relays and switches. A step portion 12 is provided at the step portion 12, and an upper convex portion 13 and a lower flange portion 14 are formed by the step portion 12. Upper convex portion 13
The height t is 0.2 mm, the outer diameter is 2.7 mm, and the radius R1 of the upper end periphery is a natural radius formed by molding. The lower collar portion 14 has a height of 0.2 mm and an outer diameter D2 of 3.0 mm.
3 mm, and the radius R3 of the upper end periphery is 0.15 mm. The radius R2 of the portion extending from the lower end peripheral edge of the upper convex portion 13 to the upper surface of the lower collar portion 14 is set to 0.15 mm. The height of the leg part 15 is 1.3 m, and the outer diameter is 1.5 m.
It is done to m.

FIG. 2 shows a base cylindrical electric contact 10' for movable contacts such as relays and switches, and a base cylindrical electric contact I for fixed contacts.
O means that the contact surface of the upper convex portion 13' of the head II has a radius of 10
It is a spherical surface with an arc of mm, and the height of the leg 15' is 1
．． The dimensions are the same except that they are 0mm.

In addition, the material of the base cylindrical electric contacts 10 and 10' are both Ag-
Cd012wt%.

Next, a conventional example will be explained with reference to Figs. 3 and 4. Fig. 3 shows a cylindrical base electric contact 2 for a fixed contact such as a relay switch. is 0
．． 4 mm, outer diameter 3 mm, and the height of the leg 6 is 1. ．． 3m
m, and the outer diameter is 1.5 mm.

Fig. 4 shows a base cylindrical electric contact 2' for movable contacts such as relays and switches, and a base cylindrical electric contact 2' for fixed contacts.
The dimensions are the same except that the contact surface of the head 1' is a spherical arc with a radius of 1.0 mm, and the height of the leg 6' is 1.0 mm.

In addition, the materials of the base cylinder type electric contacts 2 and 2' are both A g -
Cd 012wt%.

Fig. 5 shows cylindrical electric contacts 10 and 2 for fixed contacts constructed as described above, made of phosphor bronze and having a width of 4.0 mm, a length of 15 mm, and a thickness of 0.6 mm. Each leg 15.6 is inserted into a contact mounting hole 17 with an inner diameter of 1.55 mm drilled 1.2 mm away from one end of the spring base material 16, and is crimped onto the periphery of the contact mounting hole 17 to secure the fixed contact 3. made.

In addition, the base cylindrical electric contact 1 for the movable contact of the embodiment and the conventional example
0' and 2', width 4.0mm, length 25mm, thickness 0
．． The spring base material 16 shown in FIG. 6 is made of 4 mm phosphor bronze.
'Inner diameter 1.2 mm drilled at a distance of 1.2 mm from one end.
Insert the respective legs 15' and 6' into the 55 mm contact mounting hole 17 and swage them around the periphery of the contact mounting hole 17 to attach the movable contact 3'.
made.

The fixed contact 3 and the movable contact 3' of the example and the conventional example made in this way were separated by 0.5 mm and faced each other as shown in FIGS. 7 and 8, AC100V, 12A, CO8ψ=1
A life test was conducted at a contact pressure of 20 to 30 g, and the results shown in the table below were obtained.

(Margin below) The life span is determined by arc concentration due to warping of the contact head.

As is clear from the table above, the base cylindrical electrical contact 1 of the example
It can be seen that the fixed contact 3 and the movable contact 3 using O110' have a longer life than the fixed contact 3 and the movable contact 3' using the conventional trapezoidal cylindrical electric contact 2.2'. This is simply because the arc energy key suppresses the warping of the outer circumferential side of the head during contact.

(Effects of the Invention) As described above, the base cylindrical electric contact of the present invention suppresses the warping of the outer peripheral side of the head due to arc energy during contact even when the load is high, and even if there is slight warpage, the contact surface Since there is no etching around the periphery, arcs are not concentrated, welding is prevented, and the service life is increased.

[Brief explanation of drawings]

1 and 2 respectively show an embodiment of the pedestal cylindrical electrical contact of the present invention, FIGS. 3 and 4 show a conventional pedestal cylindrical electrical contact, and FIGS. 5 and 6. FIG. 7 is a diagram showing a fixed contact and a movable contact according to the embodiment; FIG. 8 is a diagram showing a conventional fixed contact and a movable contact; FIG. The figure shows a conventional tabletop cylindrical electric contact, Figure 10 shows the head heights of a fixed contact and a movable contact using a conventional tabletop cylinder type electric contact, and Figure 11 shows a conventional tabletop cylindrical electric contact. It is a figure which shows the defect of a movable contact. Applicant: Tanaka Kikinzoku Kogyo Co., Ltd. Figure 15.15...

Claims (1)

[Claims] 1) In a base cylindrical electric contact having a low-height head, a stepped portion is provided concentrically around the outer periphery of the head, and an upper convex portion formed by the stepped portion has a height t of 0.15 mm or more. outer diameter D
_1 and the outer diameter D_2 of the lower flange are D_1≦D_2-0
．． 4mm, and the leg diameter d is d≦D_2-0.4mm
The radius R_1 of the upper end periphery of the upper convex portion and the R_3 of the upper end periphery of the lower flange are set to be 0.1 mm or more, and the radius R_2 of the portion extending from the lower end periphery of the upper convex portion to the upper surface of the lower flange is made to be 0.1 mm or more. A base cylindrical electrical contact characterized by having a diameter of 0.15 mm or more.