JPH09245610A - Resistor for automobile air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resistor having a terminal construction which ensures operation of a fuse. SOLUTION: Terminals 15, 16 to which a fuse 1 is attached have respective notches 21, 22 formed therein to form a space 25 below the fuse 1. The space 25 is positioned and sized to meet L (width of the space 25) < A(the length from the apex of each terminal 15, 16 to the bottom face of the space 25) so as to avoid secondary conduction which may occur if the melted fuse comes into contact with the terminals 15, 16 again.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resistor for controlling the speed of a fan motor used in an air conditioner for automobiles.

[0002]

2. Description of the Related Art An air conditioner blower unit for an automobile has a built-in blower, which is provided with a fan in a fan scroll and is connected to a fan motor. The rotation speed of the fan motor is controlled by the blower control device. This blower control device is provided with a resistor (register) configured by connecting a plurality of resistors having a predetermined resistance value in series. By changing the total resistance value of the resistor, application to the fan motor is performed. By changing the voltage, the rotation number of the fan motor is controlled in multiple stages such as high-speed rotation, medium-speed rotation, and low-speed rotation. This blower control device is placed at a place where air flows in a duct of an automobile air conditioner for cooling.

The above register for adjusting the rotation speed of the fan motor is formed by printing a resistor pattern on a flat insulating substrate in order to meet the demands for large air volume and quietness in the passenger compartment. There is a resistor called a flat resistance, which is lightweight and small and has little ventilation resistance (for example, Japanese Utility Model Publication No. 2-145507 and Japanese Utility Model Publication No. 1-12).
5708). Furthermore, recently, a resist pattern has been developed in which the resistor pattern itself is sandwiched between an insulator and a heat dissipation plate in order from the inside to further reduce the weight and size. In such flat resistance, in general, when the fan motor stops for some reason and air is no longer blown, the resistance heats up and the cooling air stops when an overcurrent exceeding the specified value flows in the circuit. Therefore, a thermal fuse (hereinafter, simply referred to as a fuse) for disconnecting the circuit to stop the power supply to the fan motor is provided. At that time, there are various cases where the fuses are attached depending on the structure of the flat resistance.

[0004]

FIG. 4 is a schematic view showing a case where a fuse is attached to the terminal portion of the flat resistance. As shown in the figure, when a fuse is attached to the terminal portion, a pair of adjacent terminals 2 is formed to form a pedestal portion for welding the fuse 1 (for example, wire solder).
Notches 4 and 5 are formed in each of the three. Fuse 1
Is the upper portion (pedestal portion) 6 of the cutout portions 4 and 5 of the terminals 2 and 3,
7 are welded to cross-link them.

However, the terminals 2, 3 including the cutouts 4, 5
Depending on the shape, even if the fuse 1 is actuated and blown, there is a possibility that the fuse 1 will remain in a conductive state. For example, when the blown fuse 8 remains at the original pedestal 6 and the other end drops like the fuse 8 shown by the two-dot chain line in FIG. In contrast, if the size or position of the cutout portion 5 is not appropriate, the end portion of the fuse 8 on the dropped side has the same terminal 3
May re-contact with and be connected to, causing secondary conduction.

The present invention has been made in view of the above problems when a fuse is attached to a terminal portion of a flat resistance, and has a terminal structure for a vehicle air conditioner having a terminal structure capable of reliably operating the fuse. The purpose is to provide.

[0007]

In order to achieve the above-mentioned object, the present invention provides a pair of adjacent terminals to which a fuse is attached with a cutout portion facing each other, and the cutout portion allows the fuse to be formed. It is characterized by forming a space capable of preventing secondary conduction when activated.

In the present invention, when the fuse is actuated and blown, at least one end of the blown fuse is located in the space, and re-contact with the same terminal is prevented. Continuity is prevented.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In addition, a flat resistance attached to a blower unit of an automobile air conditioner will be described as an example here.

FIG. 1 is a schematic view showing a connector portion of a flat resistance according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a main portion thereof. The flat resistance is roughly divided into an upper resistance portion (not shown) and a lower connector portion 11. The upper resistance portion is formed, for example, by sandwiching the resistor pattern itself with a radiator plate such as an aluminum plate via an insulator such as a mica plate. That is, one resistor pattern is sandwiched between the insulator and the heat dissipation plate in order from the inside on both sides thereof. The lower connector part 11 is formed by insert-molding terminals (terminals) 15, 15, 16, 17, and 18 on a coupler 12 and a flange part 13 which are integrated with resin. Supporting pieces 19 and 20 are provided upright on both ends of the flange portion 13. The upper resistance part is attached to the connector part 11 via the support pieces 19 and 20 by, for example, rivets (not shown).

Here, a pair of adjacent terminals 15 and 16
Is a terminal for attaching the fuse 1 (fuse terminal)
It is used as Therefore, these terminals 15,
16 is extended above the other terminals 14, 17 and 18. The terminals 15 and 16 have notches 21 and 22 respectively.
Are formed so as to face each other, and the fuse 1 (for example, thread solder) is welded to the upper portions (base portions) 23 and 24 of the cutout portions 21 and 22 of the terminals 15 and 16 so as to bridge them. . At this time, the cutout 2 is provided below the fuse 1.
A space 25 is formed by 1 and 22.

According to the present invention, when the fuse 1 is actuated and blown, the blown fuse is prevented from re-contacting the same terminal and causing secondary conduction, so that the terminals 15 and 16 are related to the size of the fuse 1. The size and shape, more specifically, the position and size of the space 25 are defined.

Specifically, for example, as shown in FIG. 2, when the two terminals 15 and 16 are symmetrical with respect to the center line 26, the notch 2 of each terminal 15 and 16 is formed.
1, the width of the space 25 formed by 1, 22 is L, the terminal 1
The length from the vertices of 5 and 16 to the bottom of the space 25 is A
In such a case, the dimensional structure is such that the following relational expression L <A holds. Here, when the distance between the terminals 15 and 16 is D, the length of the fuse (thread solder) 1 is naturally larger than the distance D between the terminals 15 and 16 and is almost equal to the width L of the space 25. Equality,
Further, it is premised that the dimensions (height) of the pedestal portions 23 and 24 are set to be slightly larger than the width of the fuse 1 so that the fuse (soldering solder) 1 can be reliably welded and fixed. .

With such a size configuration, for example, like the fuse 8 shown by the chain double-dashed line in FIG. 3, one end of the blown fuse 8 remains at the original pedestal 23 and the other end Even if a part is dropped, the other end on the dropped side is always located in the space 25 due to the above-described size configuration, and the same terminal 24 as in the conventional case is used.
There is no re-contact with.

Therefore, by providing the space 25 as described above, even when the fuse 1 is activated, there is no possibility of causing secondary conduction, the fuse 1 can be activated reliably, and the circuit is more than specified. The fuse's original function of interrupting the circuit when an overcurrent flows is surely fulfilled.

The present invention is not limited to the above-mentioned example, and it is needless to say that the present invention can be applied to any resistor for an automobile air conditioner as long as the fuse is attached to the terminal portion. Is.

[0017]

As described above, according to the present invention, the notch provided in the terminal forms the space capable of preventing the secondary conduction when the fuse is activated. Even when the fuse is attached, the fuse can be surely operated and the function as the fuse can be surely fulfilled.

[Brief description of drawings]

FIG. 1 is a schematic view showing a connector portion of a flat resistance according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a diagram which is provided for explaining the function and effect of the present invention.

FIG. 4 is a diagram for explaining a problem.

[Explanation of symbols]

 1 ... Fuse 15, 16 ... Terminal 21, 22 ... Notch 25 ... Space

Claims (1)

[Claims] 1. A notch (21, 2) in each of a pair of adjacent terminals (15, 16) to which a fuse (1) is attached.
2) facing each other, and the cutouts (21, 22) form a space (25) capable of preventing secondary conduction when the fuse (1) is activated. Resistors for air conditioners.