JPS6117355B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a three-phase cartridge heater, and provides a long-life three-phase cartridge heater that accurately positions three heating wires in a metal pipe, equalizes temperature distribution, and provides a long-life three-phase cartridge heater. This is what I am trying to do.

Conventionally, three-phase cartridge heaters had three heating wires inserted into a metal pipe, and the three heating wires were connected using a coupling ring, but this caused the heating wires to shift in position, resulting in uneven temperature distribution. The disadvantage is that it has a short lifespan.

The present invention eliminates the drawbacks of the conventional three-phase cartridge heater, and embodiments of the present invention will be described below with reference to the accompanying drawings.

In the figure, 1 is a metal pipe, one end of which is sealed with a metal disc 2. 3 is a joint between the metal pipe 1 and the metal disk 2. Reference numeral 4 denotes a low cylindrical molded body disposed within the sealed end of the metal pipe 1, and is made by sintering magnesia powder. 5 is a cylindrical guide core made of sintered magnesia powder as shown in FIGS. 2 and 3, and has three through holes formed therein. Reference numeral 6 denotes a tripod terminal, which is formed by spot welding an L-shaped metal fitting that forms the other monopod 9 to a U-shaped metal fitting that forms the bipods 7 and 8, as shown in FIGS. 4 and 5. has been done. Each leg 7, 8, 9 of this tripod terminal 6 is inserted into each through hole of the guide core 5. This guide core 5 is arranged near the end of the metal pipe 1 on the sealing side, and the connecting portion of each leg 7, 8, 9 of the tripod terminal 6 is located on the molded body 4 side. The tip protrudes from the guide core 5 toward the opening of the metal pipe 1. 10
are three heating wires each having one end connected to each leg of the tripod terminal 6 protruding from the guide core 5;
Each heating wire 10 has an electrode terminal 1 at the other end.
1 is connected. Each of the electrode terminals 11 has the same shape as the guide core 5 and passes through another guide core 12 fitted into the opening side end of the metal pipe 1, with its tip protruding outward from the opening of the metal pipe 1. Although the guide cores 5 and 12 tend to move toward each other due to the elasticity of the heating wire 10 in the contraction direction, they are positioned by the protrusion 13 that protrudes inward of the metal pipe 1. 14 is an electrically insulating powder filled in the metal pipe 1, and 15 is a heat-resistant insulating sealing material for sealing the open end of the metal pipe 1.

In the above configuration, one end of the three heating wires 10 is connected to the tripod terminal 6 fixed to the guide core 5,
Since the other end is connected to the electrode terminal 11 held by the other guide core 12, it is placed in the metal pipe 1 under the same conditions and the temperature distribution is uniform. Therefore, it has a long life.

As is clear from the above explanation, according to the present invention, three heating wires can be arranged under the same conditions in a metal pipe with a simple configuration, the temperature distribution is made uniform, and the longer the life span, the more the industrial value is increased. is a great thing.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway sectional view of a cartridge heater showing an embodiment of the present invention, FIG. 2 is a side view of the guide core of the cartridge heater, FIG. 3 is a front view of the same, and FIG. FIG. 5 is a side view of the tripod terminal of the cartridge heater, and FIG. 5 is a front sectional view thereof. 1... Metal pipe, 5, 12... Guide core,
6...Tripod terminal, 10...Heating wire, 11...Electrode terminal.

Claims (1)

[Claims] 1 Place a guide core inside the sealed end of a metal pipe sealed on one side, connect three terminals passing through this guide core to each other on the sealed side from this guide core, and connect the other end of this terminal. A three-phase cartridge heater in which one end of each heating wire is connected to a metal pipe, another terminal is connected to the other end of each heating wire, and this terminal protrudes from an opening on one side of a metal pipe.