JPS608387Y2 - Electric heater connection terminal - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a terminal for connecting a heating wire, which is a heating element of an electric heater.

Conventionally, as shown in Fig. 1, the connection terminal of an electric heater has been made by placing the end of a heating wire 1 such as a nichrome wire on the top surface of a flat terminal 2', and connecting the tip of the heating wire 1 and the terminal 2. The ends of `` were spot welded to connect them together.

Note that 3 indicates a hole provided at the other end of the terminal 2' for attachment to the electric heater body.

However, when spot welding is performed, as shown in Figure 2, when the thin heating wire 1 and the thin plate terminal 2' are spot welded, they are fixed to the movable upper electrode 4 of the spot welding machine. Because the gap between the lower electrode 5 and the upper and lower electrodes is narrow, discharge occurs around the welding area, resulting in insufficient heating of the welding area, resulting in incomplete welding such as half-welding, and the heating wire comes off after welding. The connection strength was weak, such as cracking or breaking.

For this reason, the voltage of the electrodes is adjusted to a low range to prevent discharge, but there is a drawback that sufficient connection strength cannot be reliably obtained.

This invention proposes a connection terminal for an electric heater that aims to eliminate the above-mentioned drawbacks.

An embodiment of this invention will be described below with reference to the drawings.

As shown in Fig. 3, the end of a heating wire such as a nichrome wire and its terminal can be attached at a section, and the terminal 2 can be attached at a protrusion 6 formed by protruding a part of the upper surface of the section. Part 6
Spot welding is performed with the end of the heating wire 1 to be connected placed on top.

The protrusion molding of the terminal may be performed, for example, during press punching using a mold having a protrusion molding part during terminal production.

The appropriate amount of protrusion is the thickness of the plate.

Further, the upper surface of the protruding portion 6 is desirably flat in consideration of stability during electrode pressurization during spot welding.

Now, if the terminal 2 of this invention and the end of the heating wire 1 are spot welded, the protrusion 6 of the terminal and the heating wire 1 are energized in a state close to point contact, so that heating is performed intensively. Re,
Spot welding can be performed reliably.

Further, the upper electrode 4 and the lower electrode 5 are separated by the height of the protrusion 6 of the terminal.
Because the gap between the electrodes is widened, no discharge occurs, and
Efficient spot welding can be performed.

Further, the protruding portion 6 of the terminal has a thinner wall thickness due to the protrusion molding, and since current flows through this protruding portion, current flow resistance increases and heat generation is more likely to occur.

For this reason, the heating wire, which generally has a higher current carrying resistance than the terminal, is more likely to be melted, but since the heating efficiency of this protrusion is also improved, fusion bonding becomes more appropriate.

This eliminates bonding defects due to incomplete welding and greatly improves the bonding strength between the heating wire and the terminal.

FIG. 4 shows the connection state.

In the figure, 7 is a welding joint, and 8 is a guide hole for the heating wire 1. The heating wire 1 is passed through the guide hole 8 and supported and guided to facilitate the operation during spot welding.

In addition, since sufficient joint strength can be obtained by the welded joint of this invention, the heating wire 1 is extended to the other end and bent to engage with the connecting member, as shown by the imaginary line, and the installation is done by the operation. It also offers advantages such as easy construction.

As mentioned above, this idea is to provide an ideal connection with sufficient bonding strength by forming a part of the upper surface of the terminal joint part to protrude, so that the welding connection with the heating wire can be performed in an optimal state, and the connection can be made in an ideal state with sufficient joint strength. Can be done.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a conventional connection between a heating wire and a terminal, Fig. 2 is an enlarged vertical sectional view of a main part showing an embodiment of conventional spot welding, and Fig. 3 is a spot welding of this invention. FIG. 4 is an enlarged vertical cross-sectional view of a main part showing an embodiment of the present invention, and FIG. 4 is a perspective view showing an example of a connection state between a heating wire and a terminal of this invention. 1... Heating wire, 2, 2'... Terminal, 3
...Mounting hole, 4...Top electrode, 5.
... lower electrode, 6 ... protrusion, 7 ...
...Weld joint, 8...Guide hole.

Claims (1)

[Scope of utility model registration request] A connecting terminal for an electric heater, in which the end of a heating wire and its terminal are attached at a part, and a part of the upper surface of the terminal is protruded.