JPH09331615A - Electric connection box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a small-sized electric connection box at a low cost wherein maintenance or the like of an overcurrent protecting apparatus like a fuse is unnecessary, by installing an intermediate connection terminal having a terminal part, in each electrode of a PTC element(positive temperature coefficient resistance element) wherein electrodes are formed on both surfaces. SOLUTION: An intermediate connection terminal 10 is formed as follows; flat surfaces of two male type terminals 12, 13 formed, e.g. by punching and molding a metal plate are made to face each other, and a PTC element 11 provided with electrodes is arranged between the terminals 12 and 13. The PTC element 11 is used as a current limiting element applying the following phenomenon; when the temperature of the PTC element is raised by Joule's heat which is generated from the PTC element by an overcurrent and reaches a trip temperature, an equilibrium of high resistance value is obtained, and the flowing current value of the PTC element 11 is limited. By arranging the PTC element 11 between a relay and a bus-bar in an electric circuit, the relay and wire can be protected in the same manner as a fuse.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electric junction box.

[0002]

2. Description of the Related Art Conventionally, an electric connection box has been used to centralize functional components in terms of simplification of in-machine wiring of automobiles and home appliances, and to improve reliability, and to eliminate branching in the middle of electric wires. I have. An electric circuit is formed in the electric connection box by a bus bar made of a metal punching plate, and parts such as a connector, a terminal, a relay, and a fuse for connecting electric wires are provided.

Hereinafter, a conventional example will be described with reference to the drawings.
FIG. 3 is an exploded perspective view showing a conventional electric junction box. For example, as shown in FIG. 3, the conventional electrical junction box has intermediate connection terminals 10 ', 20', fuses 31 ', 32', 3 '.
3 ', upper case 40', connecting housing 4
1 ', 42', 43 ', 44', a substrate 50 ', a lower case 60', a bus bar 70 ', and a relay (not shown). The bus bar 70 'and the fuse 31' are electrically connected using the intermediate connection terminal 20 ', and the bus bar 70' and the relay (not shown) are electrically connected using the intermediate connection terminal 10 '. Generally, the intermediate connecting terminals are stamped and formed of a metal plate and have various shapes. For example, the intermediate connecting terminals 10 'and 20' shown in FIG. The two male terminals are electrically connected. The intermediate connection terminals 10 'and 20' are connected to the connection housings 41 'and 42' by the fuses 31 'and 3'.
2'and 33 'are connection housings 42', 43 'and 4
It is stored in each 4 '. A corresponding fuse is connected to the other end of the bus bar 70 'connected to the relay, so that the switch circuit or the excitation circuit of the relay is protected from a current equal to or higher than a set value (hereinafter referred to as overcurrent). The components shown in the figure are housed in the lower case 60 'in the direction of the arrow in the figure.

However, in the conventional electrical junction box, since the fuse must be connected to the terminal as a separate component as described above, in order to secure the installation space for the fuse (including the housing for connection, the fuse body, etc.). There was a problem that it was difficult to downsize. Incidentally, the number of electric circuits in the electric junction box is increasing with the recent progress of electronics, and the number of fuses used is also increasing. Further, since the fuse is blown and cannot be reused when an overcurrent flows, there is a problem that maintenance such as replacement of parts takes time when the fuse is blown.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide an inexpensive electrical junction box which does not require maintenance of an overcurrent protection device such as a fuse. And

[0006]

The electrical junction box of the present invention comprises:
The positive temperature coefficient resistance element (PTC element) having electrodes formed on both surfaces is provided with an intermediate connection terminal provided with a terminal portion on each electrode.

A positive temperature coefficient resistance element (hereinafter referred to as PTC element) may be used as a current limiting element.
The reason for its use is that the PTC element shows a low resistance value in a low temperature region, but the resistance value rapidly increases at a certain temperature or more (1000 times or more the normal resistance value).
It has the general characteristic of temperature-resistance. The temperature at which the resistance value suddenly increases is generally called a trip temperature. This PTC element is used as a current limiting element by utilizing the general characteristic of temperature-resistance. This is because the temperature of the PTC element rises due to the Joule heat generated from the PTC element due to the overcurrent, and when the trip temperature is reached, the PTC element is in an equilibrium state with a high resistance value.
This is a phenomenon that the passing current value of the element is limited.

Therefore, by arranging a positive temperature coefficient resistance element (PTC element) between the relay and the bus bar on the electric circuit, the temperature of the element rises when an overcurrent occurs and the resistance suddenly increases when the trip temperature is reached. The value increases and the current can be suppressed to protect the relay or electric wire like a fuse. When the current value becomes smaller than the set value, the PTC
Since the element does not generate heat, the temperature of the element is lowered by natural cooling and returns to the resistance value at room temperature. That is, the electric connection box of the present invention includes the intermediate connection terminal in which the terminal is connected to the electrode of the PTC element having the fuse replacement function.
It is compact and does not require maintenance even if the overcurrent protection function is activated.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view showing an electric junction box according to the present invention. 2 (a) is a perspective view showing an intermediate connection terminal relating to the electric connection box of the present invention, and FIG.
FIG. 4 is a partially enlarged side view of an intermediate connection terminal relating to the electric junction box of the present invention. As shown in FIG. 1, the electrical junction box of the present invention is a positive temperature coefficient resistance element (PT) having electrodes formed on both surfaces.
It is characterized in that each electrode of the (C element) is provided with an intermediate connection terminal 10 in which terminal portions 12 and 13 are provided.

As shown in FIG. 1, the electric connection box of the present invention is
The intermediate connection terminals 10 and 10 ', the upper case 40, the connection housing 41, the substrate 50, the lower case 60, the bus bar 70, and a relay (not shown). The bus bar 70 and the relay are electrically connected using the intermediate connection terminals 10 and 10 '. In addition, the intermediate connection terminal 10,
10 ′ is housed in the connection housing 41. Also,
Each part in the drawing is housed in the lower case 60 in the direction of the arrow in the drawing.

The intermediate connection terminal 10, which is a feature of the electric junction box of the present invention, will be described in detail here. As shown in FIG. 2A, the intermediate connection terminal 10 has, for example, two female terminals 12 and 13 formed by punching and molding a metal plate, with their flat surfaces faced to each other, and the PTC element 11 with an electrode interposed therebetween. It is arranged and formed. PTC element with electrode 11
Is a plate-like member having a surface shape equivalent to the flat surface of the terminals 12 and 13 as shown in FIG.
Electrodes 11b are formed on both sides of 1a. The terminals 12 and 13 may have any orientation and shape (male or female), but as shown in FIG. 2A, the female terminals 12 and 13 are arranged in opposite directions. When done,
It is preferable because two different male terminals facing each other can be electrically connected. In addition, the intermediate connection terminal 1 shown in FIG.
With the PTC element 11a built in 0, the switch circuit or exciting circuit of the relay connected to the intermediate connection terminal 10 can be prevented from being damaged by the occurrence of overcurrent.

As described above, in the electrical junction box of the present invention, the PTC element 11a is connected to the intermediate connection terminal 10 without using a fuse.
By including the fuse, a space for installing a fuse (including a housing for connection, a fuse body, etc.) is not required, so that it is possible to reduce the number of components, downsize, and reduce cost.

[0013]

As described above, according to the electric connection box of the present invention, the intermediate connection terminal in which the terminal portion is provided on each electrode of the positive temperature coefficient resistance element (PTC element) having the electrodes formed on both surfaces is provided. Since it is provided, it is possible to provide an inexpensive electrical junction box that is compact and does not require maintenance of an overcurrent protection device such as a fuse.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an electric junction box of the present invention.

FIG. 2 is a perspective view and a partially enlarged side view showing an intermediate connection terminal relating to the electric connection box of the present invention.

FIG. 3 is an exploded perspective view showing a conventional electric junction box.

[Explanation of symbols]

 10 Intermediate connection terminals 12 and 13 terminals

Claims (1)

[Claims] 1. An electrical junction box comprising a positive temperature coefficient resistor element (PTC element) having electrodes formed on both sides, and an intermediate connecting terminal provided with a terminal portion on each electrode.