JPH01152704A - Composite electronic component - Google Patents

Abstract

PURPOSE:To gain an easy connection to an electric apparatus as well as to reduce the installation space, by making an integral electronic component by combination of a protective element against excess current and a protective element against a surge voltage. CONSTITUTION:A positive temperature coefficient thermistor element 1 and a varistor element 3 are combined in layers with an insulating spacer 3 put between the two. The first external electrode 6 is connected to the input side, the second external electrode 7 is connected to an electric apparatus to be protected as a load and the third external electrode 8 is grounded, meaning that the positive temperature coefficient thermistor element 1 is connected in series and the varistor element 2 is connected in parallel to the load. In such a connection, the positive temperature coefficient thermistor element 1 functions to protect an excess current and the varistor element 2 functions to protect a surge voltage. Since the protection of both an excess current and a surge voltage can be done by an integral electronic component, an easy connection is available and only a small space is needed for installation.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a composite electronic component having a protection function against overcurrent and a protection function against surge voltage in a single component.

<Prior Art> Conventionally, positive characteristic thermistors have been used for overcurrent protection for various electrical devices, and varistors have been used for surge voltage protection.

<Problems to be Solved by the Invention> Incidentally, electrical equipment to be protected often requires protection against both overcurrent and surge voltage, and in such cases, a positive temperature coefficient thermistor, which is a discrete component, is required. and the varistor are connected to electrical equipment separately.

However, if two types of electronic components were connected separately in this way, the connection work would be troublesome, and
The space for installation becomes larger.

The present invention was made in view of the above-mentioned problems, and includes an element having an overcurrent protection function and an element having a surge voltage protection function, which are integrated into a single electronic component.
The purpose is to simplify the connection work to electrical equipment and reduce the installation space.

Means for Solving the Problems> In order to achieve the above object, the present invention includes a positive temperature coefficient thermistor element and a varistor element, and integrates these two types of elements by laminating them via an insulating spacer. One electrode of each element is led out to the same side surface of the laminate made of the two types of elements and an insulating spacer and commonly connected to the first external terminal, and the other electrode of each element is connected to the same side of the laminate made of the two types of elements and an insulating spacer. A composite electronic component was constructed by leading out to different side surfaces and connecting to a second or third external terminal.

<Function> In the above configuration, if the first external terminal is connected to the input side, the second external terminal is connected to the electrical equipment to be protected as a load, and the third external terminal is grounded, the The positive temperature coefficient thermistor elements are connected in series, and the varistor elements are connected in parallel. By being connected in this manner, the positive temperature coefficient thermistor element exhibits an overcurrent protection function for the load, and the varistor element exhibits a surge voltage protection function.

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings.

FIG. 1 is an external perspective view of a composite electronic component according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of its main body.

The composite electronic component of this embodiment includes a positive temperature coefficient thermistor element 1
, a varistor element 2 , and an insulating spacer 3 . In this embodiment, the two types of elements 1.2 and the insulating spacer 3 are both square plate-shaped with the same size, and each of the two types of elements 1.2 is plural. And these two types of elements 1.2 and insulating spacer 3 are two types of elements! ,2
They are integrally laminated with an insulating spacer 3 sandwiched between them to form a laminated chip. A cover unit 4.5 is laminated on the outermost layer of this laminate.

In the figure, 6 is the first external electrode to be connected to the input side, 7 is the second external electrode to be connected to the load side, and 8 is the third external electrode to be grounded.
These external terminals 6°7.8 are formed on different side surfaces of the laminate. That is, the first external electrode 6 is formed on one longitudinal side of the laminate, the second external electrode 7 is formed on the other longitudinal side of the laminate, and the third external electrode 7 is formed on the other longitudinal side of the laminate. 8 are formed on both side surfaces of the laminate in the transverse direction. The connection state between these external electrodes 6.7.8 and each element 1.2 will be described later.

As shown in FIG. 3, the positive temperature coefficient thermistor element l has electrodes 1b on each of the amphibian surfaces of a rectangular plate-shaped thermistor body 1a.
, lc are formed, and the picture electrode 1b , Ic
are mutually led out to both end faces in the longitudinal direction of the thermistor body 1a. In this embodiment, in the thermistor element 1a, (B ao, 5ssY o, oos)T i+, ooa
o 3+ Made of 0.5 mol% MnO, vertical and horizontal 7
A fired square plate having dimensions of mmX 10 +nm and thickness of 0.4+nm was used. Moreover, the picture electrode 1b.

The electrode 1b on the input side of the lc is a general electrode, and is formed by baking a conductive paste containing silver as a main component at about 800°C. The electrode 1c on the load side is an ohmic electrode, and is formed by baking a conductive paste containing silver and zinc as main components at about 600°C.

As shown in FIG. 4, the varistor element 2 has electrodes 2b and 2c formed on the amphiboid surfaces of a square plate-shaped varistor element 2a, and one electrode 2b is connected to the positive temperature coefficient thermistor element l. It is led out to the end face in the longitudinal direction of the varistor body 2a on the same side as one electrode lb, and the other electrode 2c
is a positive characteristic thermistor element! The picture electrode 1b is led out to the end face on the side different from Ic, that is, to both end faces in the transverse direction of the varistor element body 2a. In this embodiment, as the varistor body 2a, 0.98Z no + 0.0Q5B two 3+
Q, 005M n.

+Q, Q05Cot03+0.005Sb20s (molar ratio) was used as the material, and a fired square plate of the same size as the positive temperature coefficient thermistor element 1a, that is, 7 mm x 10 mm x O, 4 mm, was used. Moreover, each electrode 2b.

2c is a general electrode, which was formed by baking a conductive paste containing silver as a main component at about 800°C.

Then, the positive temperature coefficient thermistor element l and the varistor element 2 are reversed one by one in the stacked body, as shown in FIG. electrode 1b (or lc,
Solder paste is applied to each electrode 1b, tc, 2b, 2c so that the electrodes 2b, 2c) face each other, and they are joined by hot air treatment.

In this embodiment, the cover integral 4.5 includes the electrode 1b
, lc , 2b , 2c are not formed, but the positive temperature coefficient thermistor element 1 is used without using such an integrated cover.
Alternatively, the varistor element 2 may be located at the outermost layer of the laminate.

By stacking the two types of elements 1.2 in the same direction as described above, each element has an electrode 1b of 1°2 on each side of the stack.
, Ic, 2b, and 2c are exposed vertically aligned. The external electrode 6.7.8 described above is
ili electrodes 1b, 1c, 2b, 2c (1) Formed on each side surface of the laminate to cover the N peaks and connected to the electrodes 1b, lc, 2b, 2c of the corresponding element 1.2. . That is, the first external electrode 6 is formed on one side surface in the longitudinal direction of the laminate, and is connected to one electrode 1a of the positive temperature coefficient thermistor element l and one electrode 2 of the varistor element 2.
It is commonly connected to a. The second external electrode 7 is formed on the other longitudinal side surface of the laminate and is connected to the other electrode 1c of the positive temperature coefficient thermistor element l. The third external electrode 8 is formed on both side surfaces of the laminate in the transverse direction and is connected to the other electrode 2C of the varistor element 2.

By connecting as described above, a laminated chip type composite electronic component having an equivalent circuit as shown in FIG. 5 can be obtained.

In the above configuration, when the first external electrode 6 is connected to the input side, the second external electrode 7 is connected to the electrical equipment to be protected as a load, and the third external electrode 8 is grounded, the Thus, the positive temperature coefficient thermistor element 1 is connected in series, and the varistor element 2 is connected in parallel. By connecting in this manner, the positive temperature coefficient thermistor element 1 exhibits an overcurrent protection function for the load, and the varistor element 2 exhibits a surge voltage protection function.

Regarding the composite electronic component of the above example, when the characteristics of the positive temperature coefficient thermistor element l and the varistor element 2 were measured with the first external electrode 6 on the + side, it was found that the positive temperature coefficient thermistor element l had the sixth The voltage-current characteristics shown in the figure were obtained. As is clear from this characteristic diagram, a current limiting effect up to 0.3 A is observed. In addition, varistor element 2
For V (1 mA) = 70 V, α = 15 values were obtained.

In the embodiment, only the electrode 1c on the load side of the positive temperature coefficient thermistor element 1 was used as an ohmic electrode, but the other electrode 1b of the positive temperature coefficient thermistor element 1 and the picture electrodes 2b and 2c of the varistor element 2 could be used as ohmic electrodes. Good too. Also,
Positive characteristic thermistor element l has P bT io, system and v, 0
3-based materials, S rT to, varistor element 2, and T
ies-based materials may also be used.

<Effects of the Invention> As described above, according to the present invention, a single electronic component provides an overcurrent protection function and a surge voltage protection function. Compared to protection against current and surge voltage, the connection work is easier and requires less installation space.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view of an embodiment of the present invention, Fig. 2 is an exploded perspective view of its main body, Fig. 3 is a perspective view of a positive temperature coefficient thermistor element, Fig. 4 is a perspective view of a varistor element, and Fig. 4 is a perspective view of a varistor element. FIG. 5 is an equivalent circuit diagram, and the sixth factor is a voltage-current characteristic diagram of the positive temperature coefficient thermistor element portion. ■... Positive temperature coefficient thermistor element, 2... Varistor element, 3... Insulating spacer, 6... First external electrode, 7
. . . second external electrode, 8 . . . third external electrode.

Claims (1)

[Claims] (1) A positive temperature coefficient thermistor element and a varistor element are provided, these two types of elements are laminated together via an insulating spacer, and one electrode of each element is connected to a laminate consisting of the two types of elements and the insulating spacer. The electrodes are led out to the same side surface and commonly connected to the first external terminal, and the other electrodes of each element are led out to mutually different side surfaces of the laminate and connected to the second or third external terminal. A composite electronic component featuring: