JPH02151242A - Thermal fuse installation method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a method for attaching a temperature fuse to equipment in which the outer periphery of a small electric motor, small transformer, electromagnetic solenoid, etc. is coated by integral molding of an insulating thermosetting resin. It is.

[Conventional technology]

Conventionally, small electric motors, small transformers,! In order to prevent overheating or fire accidents due to excessive loads or short circuits in equipment such as magnetic solenoids, a temperature fuse 3 is connected between the windings or at the lead wire installation position to prevent overloads or short circuits. When an accident occurs, the temperature fuse 3 is fused to prevent a fire accident.

In devices constructed by integral molding of thermosetting resin, the temperature fuse 3 may vary depending on the resin molding temperature during integral molding.
Because thermal stress is applied to the temperature fuse 3, which causes deterioration of the fusing characteristics of the temperature fuse 3 or the melting of the temperature fuse, it is impossible to arrange it between the windings. A method has been adopted in which the temperature fuse 3, which is coated with a heat shield, is fixed using a mounting bracket 8 or the like.

Due to the characteristics of the temperature fuse 3, it is necessary for the temperature sensing part 4 to be in close contact with the outer periphery 2 of the device, so the mounting seat of the temperature fuse 3 and the screw seat for fixing the mounting bracket are formed at the same time when the device is integrally molded, or by post-processing. It was necessary to take measures such as forming

In addition, additional parts such as the insulating tube 7, the mounting fittings 8, and the fixing screws 9 are required, and the installation is labor-intensive, resulting in an increase in the number of man-hours.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned conventional problems, and provides a simple temperature fuse that allows the temperature fuse to be placed in close contact with a predetermined position on the outer periphery of the device, and that can reliably shut off the power supply. The purpose is to provide an installation method for

[Means to solve the problem]

In order to achieve the above object, a temperature fuse 3 is arranged on the outer periphery 2 of the device whose outer periphery is molded with an insulating thermosetting resin, and the temperature fuse 3 is attached to a heat shrinkable tube attached to the outer periphery 2. The temperature fuse 3 was tightly fixed to the outer periphery 2 of the device by covering it with a heat shrink tube 5 and heating the heat shrink tube 5.

[Effect]

According to the above configuration, the temperature fuse 3 is tightly fixed at a predetermined position of the device by the heat shrink tube 5, and when an accident such as an overload or a short circuit occurs, it melts due to a rise in temperature around the device, cuts off the current, and ignites. Work to prevent accidents.

Further, the live portion of the temperature fuse 3 is shielded by the covering of the heat shrink tube 5, which serves to prevent the live portion from being exposed and maintain insulation properties.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings, taking a small molded electric motor as an example.

In Fig. 1, reference numeral 1 is an electric motor, in which a stator winding (not shown) is wound around a stator core (not shown), and the outer periphery 2 including the stator core and stator winding is made of thermosetting material. It is molded with resin, and the heat-sensitive part 4 of the temperature fuse 3 is disposed at a predetermined position approximately in the center of the outer periphery 2 so as to be in close contact with the outer periphery 2.

The temperature fuse 3 consists of a heat sensitive part 4 and a drawer 6, and has a shape in which the drawer 6 is drawn out concentrically or in the same direction, and is placed on the outer periphery 2 of the electric motor 1.
The position where the temperature rise is the highest is selected and placed.

Reference numeral 5 denotes a heat-shrinkable tube, which has an inner circumference larger than the outer circumference 2 and a width sufficient to cover the live part of the temperature fuse 3, and covers the outer circumference 2 with the heat-sensitive part 4 of the temperature fuse 3 in between, and is heated by hot air heating or the like. It contracts and fixes the temperature fuse 3 in close contact with the outer periphery 2 of the electric motor 1. At the same time, exposed live parts such as the lead 6 of the temperature fuse 3 are insulated.

In addition, by providing a recess that matches the shape of the temperature fuse 3 at the mounting position of the temperature fuse 3 on the outer periphery 2, and installing the temperature fuse 3, the motor 1 has an almost cylindrical shape with no protruding parts on the outer periphery 2. This prevents the temperature fuse 3 from breaking due to handling, etc., and also provides a pull-out groove for the pull-out lead 6 of the temperature fuse 3 so that it can be pulled out through the groove and insulated with ease. can do.

〔Effect of the invention〕

Since the present invention is configured as described above, the electric motor l
No special mounting structure was required on the outer periphery 2, and the temperature fuse 3 could be mounted in accordance with the optimum position for temperature rise on the outer periphery 2.

Furthermore, parts such as the mounting bracket 8 and fixing screws 9 and the work to install them can be reduced, and workability and efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a sectional side view of a main part showing the temperature fuse installation method of the present invention, and FIG. 2 is a partially sectional side view showing a conventional example. In the figure, ■ is the electric motor, 2 is the outer circumference of the electric motor l, 3 is the temperature fuse, 4 is the heat sensitive part, 5 is the heat shrink tube, 6 is the drawer lead, 7 is the insulating tube, 8 is the mounting bracket, and 9 is the fixed bracket. It is ji.

Claims (1)

[Claims] By placing a thermal fuse around the outer periphery of a device whose outer periphery is molded with insulating thermosetting resin, covering the thermal fuse with a heat shrinkable tube attached to the outer periphery, and heating the heat shrinkable tube. , a thermal fuse installation method in which the thermal fuse is closely fixed to the outer periphery of the device.