JPH03230484A - Surge absorbing element for overvoltage/overcurrent protection - Google Patents

Abstract

PURPOSE:To obtain the overvoltage/overcurrent protecting function minimizing the effect of heating to the outside by inserting a surge absorbing element and a low-melting point metal wire into an inorganic material outer body. CONSTITUTION:Lead pins 4 are installed and fixed on the base material 5 of a PBT. A micro-gap type surge absorbing element 2 is used, a zinc wire 3 is used for a low-melting point metal wire, and a cylindrical cover glass outer body 1 made of lead glass is used for an inorganic material outer body. The outer body 1 is fixed to the base material 5, the absorbing element 2 and the metal wire 3 are inserted into the outer body 1, both ends are soldered to the pin 4, and then a PBT resin case is put on the base material 5.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a surge absorbing element having an overvoltage/overcurrent protection function, and in particular, it suppresses the influence of heat on the outside and improves the mounting characteristics on a board. This invention relates to a surge absorbing element with improved properties.

[Prior Art] Surge absorption elements are used to protect equipment connected to telephone lines, such as telephones, facsimiles, and telephone exchanges, from surges. Furthermore, the overvoltage/overcurrent protection function is such that when the surge absorption element is overloaded with overvoltage AM flow, the low melting point metal wire is melted by heat and disconnected, thereby protecting the surge absorption element from the overvoltage/overcurrent. In a conventional surge absorption element having such an overvoltage/overcurrent protection function, a low melting point metal wire is attached to the surface of a gear knob type or micro gear/buzzer type surge absorption element, and the low melting point metal wire and the sun absorption element are connected to each other. A surge absorbing element F for overvoltage and overcurrent protection was provided with a structure in which the surrounding area was covered with an inorganic material jacket. It has a structure in which lead terminals are provided at both ends of this inorganic material outer cover.

That is, the conventional surge absorbing element with the A voltage overcurrent protection function has a structure as shown in FIG. 2 disclosed in Japanese Patent Laid-Open No. 63-205026.

In the conventional technology, the external lead terminals are 3 or 4 terminals, but one of the three terminals or two of the four terminals is linear and the lead position is unstable, so when mounting on the board, It has the disadvantage that it is difficult to install.

In addition, as shown in the example described in Patent Publication No. 1983-205026, the cover glass is exposed, so when mounting on a board, the cover glass is in direct contact with the board. There is. For this reason, when overvoltage and overcurrent enter the surge absorption element of conventional overvoltage and overcurrent protection, the surge absorption element inside the cover glass generates heat and cuts off the low melting point metal wire with heat. It has the disadvantage of causing adverse thermal effects (heat generation, smoke generation) on the board on which it is mounted.

In order to solve the drawbacks of the prior art, the present invention fixes the lead wire of a gap type or micro gear knob type surge absorbing element and a low melting point metal wire to a lead bin fixed to a base made of a prefabricated resin or the like. An object of the present invention is to provide a sun absorption element having an overvoltage/overcurrent protection function and having a structure in which the peripheral part of a cover glass envelope is fixed with resin or the like, and a space is provided around the central part where a lot of heat is generated.

[Structure of the Invention] [Means for Solving the Problems] The gist of the present invention essentially consists of a gap type or micro gear knob type surge absorption element and a low melting point metal wire provided in contact with it. In a surge absorption element having an overvoltage/overcurrent protection function, the gap type or micro-gear knob type surge absorption element and the gap type or micro-gear knob type surge absorption element are provided inside an inorganic outer covering having an inner diameter slightly larger than the gap type or micro-cap type gutter absorption element. An overvoltage/overcurrent protection function having a structure in which the low melting point metal wire is inserted, both ends of the inorganic outer covering are fixed to a resin base, and a space is provided around the middle part of the inorganic outer covering. This is a surge absorption element having the following characteristics. A suitable structure is such that a lead pin is driven into the resin base of the surge absorbing element in advance, and both ends of the gap type or micro gap type surge absorbing element and both ends of the low melting point metal are fixed to the lead pin. be.

According to the present invention, as a substrate for a surge absorbing element, 0.5 to 1
．． A base material having lead pins of about 0 mm diameter fixed thereon is used, and the base material has a structure to which both ends of an inorganic outer cover or a cover glass outer cover can be fixed. The inner diameter of this cover glass envelope is slightly larger than the outer diameter of the gap-type or micro-gear knob-type surge absorption element, so that a low melting point metal wire can be inserted into the gap space. The total length of this inorganic outer cover is longer than the main body length of the gap type or microphone I-1 gap type surge absorption element inserted inside, and when the outer cover is fixed with resin, the inner gap type or The structure makes it difficult for the heat of the micro gear knob type surge absorption element to be transmitted to the resin through the outer body.

After attaching the mantle to such a base material, a gap type or micro gear knob type surge absorption element and a low melting point metal wire are inserted inside, and the surge absorption element and both ends of the low melting point metal wire are inserted. are electrically connected to lead bins fixed to the base material. This connection method includes soldering,
Slot welding, 7-tooth welding, etc. are possible, but there are no particular limitations.
In this way, the entire mantle, surge absorbing element, and low melting point metal wire attached to the base material are covered and protected with a cover case made of resin like the base material.

The surge absorbing element having the overvoltage/overcurrent protector of the present invention has a gear knob type or microphone [1 gap type surge absorbing element] inside an inorganic outer covering having an inner diameter slightly larger than that of the gap type or microphone U gear/branch. Insert the formula Zashi absorption element f and the low melting point metal wire, and further fix both ends of the inorganic outer covering to a resin base, and create a structure in which a space is provided around the middle part of the inorganic outer covering as described in 1Vii. By doing so, the influence of heat generation on the outside can be minimized. Further, by attaching a lead bin to the resin base in advance, it is possible to have a structure that can improve work efficiency when mounting the surge absorbing element.

The surge absorbing element of the present invention can be used in devices that can be connected to telephone lines, such as telephones, facsimile machines, and telephone exchanges.

Next, the surge absorbing element with the overvoltage/overcurrent protection function of the present invention will be explained using a specific example, but the present invention is not limited by the explanation.

[Example] This embodiment is shown in FIG.

As shown in FIG. 1, the PBT base material 5 is coated with 0.
A glued pin 4 with a diameter of 8m1lΦ and a length of am was installed on the base material 5 and fixed.

As a surge absorption element, the outer size is 7.0111 length x 3.
A microgap type surge absorbing element 2 having a diameter of 311DΦ was used, and a zinc wire 3 was used as the low melting point metal wire. Also,
As inorganic material outer cover, length 10゜0m, inner diameter 3.7㎜
A cylindrical cover glass envelope 1 made of lead glass having a diameter of Φ was used.

As shown in the figure, the cover glass envelope 1 is attached to the base material 5,
After fixing and inserting the surge absorbing element 2 and the low melting point metal wire 3 into the cover glass envelope 1 as shown in the figure,
Both ends of each were soldered into the lead bin 4.

Furthermore, on this base material 5, the same P with external dimensions 9 x 9 x 18 m is added.
It was covered with a BT resin case (not shown).

A surge absorbing element with a conventional overvoltage/overcurrent protection function and a surge absorbing element according to an embodiment of the present invention are each directly fixed to a paper phenol substrate (resin overcoated), and an overvoltage current of 600 VAC, 2.2 A is applied. The current is connected in series to the micro gear type 71 surge absorption element 2 and the low melting point metal wire 3.
Table 1 shows the cut-off time of the low melting point metal wire and the condition of the paper phenol substrate when the voltage was applied.

Tortoise ±1 Conventional product Example product cut-off time Fused in 2 to 6 seconds Fused in 2 to 6 seconds Paper phenol Overcoat Overcoated substrate
Partial elution of resin, no change in resin - As shown in the figure, the product of the present invention has a space around the center of the internal inorganic jacket, so when overvoltage and overcurrent are applied, , it is possible to reduce the transmission of heat from the micro-gap surge absorption element to the outside through the cover glass envelope, suppress the thermal effect on the board on which it is mounted, and improve safety.ii
Ding no i konaru.

In addition, compared to conventional products, the surge absorbing element has a
It can be fixed to the base by passing it through the lead bin, and the low melting point metal wire is also fixed to the base by passing it through the lead bin. When mounting the board, it can be assembled using the lead bin of the base, and it can be oriented in the same direction. As a result, work efficiency can be significantly improved.

[Effects of the Invention] The surge absorbing element having an overvoltage A current protection function of the present invention has a gap type or micro gap type surge absorbing element inside an inorganic jacket having a slightly larger inner diameter than a gap type or micro gap type surge absorbing element. Due to the structure in which the type surge absorbing element and the low melting point metal wire are inserted, the following remarkable technical effects could be obtained.

First, it was possible to provide a surge absorption element having an overvoltage/overcurrent protection function that can minimize the influence of heat generation on the outside.

Second, the present invention provides a surge absorbing element for overvoltage/overcurrent protection having a structure that can increase work efficiency when mounting the surge absorbing element by attaching lid pins to the resin base in advance.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a surge absorbing element having an overvoltage/overcurrent protection function according to the present invention. FIG. 2 is a sectional view of a conventional surge absorption element for overvoltage and overcurrent protection. [1. 29. . 3. 40. . Explanation of symbols of main parts 0. , Inorganic outer cover or cover ■1 Gear/Z type 1. , low melting point metal wire 0. Lead pin base material glass envelope) absorption element

Claims (1)

[Claims] 1. A surge absorption element having an overvoltage/overcurrent protection function consisting essentially of a gap type or micro gap type surge absorption element and a low melting point metal wire provided in contact with the surge absorption element, comprising: It has a structure in which the gap type or microgap type surge absorbing element and the low melting point metal wire are inserted into an inorganic outer cover having an inner diameter slightly larger than that of the gap type surge absorbing element, and the inorganic outer cover A surge absorbing element having an overvoltage/overcurrent protection function and having a structure in which both ends of the inorganic outer cover are fixed to a resin base, and a space is provided around the center of the inorganic outer cover. 2. Lead pins are driven into the resin base of the surge absorbing element in advance, and both ends of the gap type or micro gap type surge absorbing element and both ends of the low melting point metal are fixed to the lead pins. A surge absorption element having an overvoltage/overcurrent protection function according to claim 1.