JPH0332521Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The invention is suitable for preventing oxidation when a wire is continuously heated by direct current, especially when the heating temperature is high enough to promote oxidation. The present invention relates to a wire current heating device characterized by a simple structure.

[Conventional technology]

When the wire is brought into contact with multiple pairs of contact rolls placed along the feed path and energized directly, if there is an oxide layer on the surface of the wire, sparks will be generated when it comes into contact with the contact rolls, causing spark flaws in the wire. Product quality deteriorates. Even if the wire itself does not have an oxide layer, if the purpose of heating is quenching, solution treatment, etc., and the wire has a large diameter, even if the wire is heated by direct current, which is called rapid heating, the wire will be exposed to the high temperature range. During this time, oxidation is promoted and current flow becomes unstable.

One of the countermeasures is to provide an anti-oxidation atmosphere cylinder between one electrode and the other electrode, and use this cylinder as a passage for the wire, as described in Japanese Patent Application Laid-Open No. 52-59010. There is a way.

[The problem that the idea attempts to solve]

However, in this method of providing an antioxidant atmosphere cylinder between the electrodes, the wire rod is heated in a high temperature range (e.g.
When heating to 900℃~1000℃),
There was a problem that the wire rod was oxidized between the electrode (contact roll) and the oxidation-preventing atmosphere cylinder.

The present invention was developed to solve the above problem, and it is possible to reliably prevent oxidation of the wire even when the wire is heated to a high temperature range, and without providing excessive oxidation prevention means. It is an object of the present invention to provide a wire current heating device that can realize this.

[Means to solve the problem]

In order to achieve the above object, the present invention includes first and second power supply boxes that are arranged sequentially at a predetermined interval in the wire feeding direction and have built-in pairs of contact rolls, and a heating power source. A power supply circuit that supplies power to the contact roll includes first and second plate-shaped busbars extending from the heating power source to a predetermined position on the wire feed path, and connecting terminals of the first power supply box and the first busbar at both ends, respectively. A first coaxial bus bar that is connected and has a tubular shape that is coaxial with the wire feeding passage; and a second coaxial bus bar that has a tubular shape that is coaxial with the wire feeding passage and whose both ends are connected to the connection terminal of the second power supply box and the second bus bar, respectively. A third power supply box disposed downstream of the second power supply box, a second heating power source that supplies power to the contact rolls built into each of the second and third power supply boxes, and one end of the power supply box. A third coaxial busbar has its other end connected to the second heating power source via a third plate-shaped busbar;
A fourth coaxial busbar and an inert gas or reducing gas supply source, the other end of which is connected to a second heating power source via a fourth plate-shaped busbar, are provided in the power supply box, and a third coaxial busbar and a third coaxial busbar are provided. The ends of the coaxial busbars No. 4 on the power supply box side are opened into the corresponding power supply boxes via insulating short tubes, and the mutually opposing ends of both coaxial busbars are connected with an insulating tubular joint, and this joint and the first and Each of the second coaxial busbars had a gas inlet, and each gas inlet was connected to a gas supply source through piping.

[Effect]

In the present invention, the wire is not completely shielded from the outside air between the first and second power supply boxes where the wire temperature is in the low temperature range, but between the second and third power supply boxes where the wire temperature is in the high temperature range. Since the wire does not come into contact with the outside air between the two, oxidation of the wire is almost completely prevented.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, E is a heating power source, and S1, S2, and S3 are power supply boxes, each of which houses a pair of contact rolls C. Contact roll C
The pair of wire rods circumferentially contact the wire rod W traveling in the feeding path with a predetermined pressing force. B is a plate-shaped bus bar, and PB1, PB2, PB3, and PB4 are coaxial bus bars made of conductive tube material and arranged coaxially with the feeding path of the wire W. The function of this coaxial busbar is disclosed in Japanese Utility Model Application No. 1983-6216.

One end of the coaxial busbar PB1 is connected to the connection terminal X of the power supply box S1, and the other end is connected to the plate-shaped busbar B. One end of the coaxial busbar PB2 is connected to the connection terminal X of the power supply box S2,
The other end is connected to a plate-shaped busbar B. The coaxial busbars PB1 and PB2 are provided with a gas inlet In for gas G, and this gas inlet In is connected via a pipe P to a gas supply source of an inert gas or a reducing gas (not shown).

One end of the coaxial busbar PB3 is connected to the connection terminal X of the power supply box S2, and an electrically insulating short pipe JP is attached to the one end, and the coaxial busbar PB3 opens into the power supply box S2 through the short pipe JP. One end of the coaxial busbar PB4 is connected to the connection terminal X of the power supply box S3, and an electrically insulating short pipe JP is attached to the one end, and the coaxial busbar PB4 opens into the power supply box S3 through the short pipe JP.

The other ends of the coaxial busbars PB3 and PB4 are each connected to a heating power source E via a plate-shaped busbar B, and are also connected by a straight portion ta of an electrically insulating T-joint. A branch portion tb protruding from the straight portion ta of this T-joint is connected via a pipe P to a gas supply source of an inert gas or reducing gas (not shown).

Note that the wire W travels in the direction of the arrow, and is heated to approximately 500°C to 600°C (referred to as a low temperature range in this embodiment) by being energized between the power supply boxes S1 and S2, and the temperature is increased between the power supply boxes S2 and S3. 900℃~ when energized
The temperature is raised to about 1000°C (referred to as a high temperature range in this example).

In this configuration, when heating, the coaxial busbar PB
1 and PB2 are supplied with an inert gas or a reducing gas from a gas supply source (not shown) through the pipe P and the gas inlet In provided in each, and the wire W exiting the power supply box S1 is supplied with an inert gas or a reducing gas. Inside the coaxial busbar PB1 filled with reducing gas,
Then, it travels within the coaxial busbar PB2 and enters the power supply box S2.

In addition, the coaxial busbars PB3 and PB4 have conduits P
An inert gas or a reducing gas is supplied from a gas supply source (not shown) through a branch part tb provided at the T joint, and the space is filled with these gases.
Since the coaxial busbar PB3 is connected to the power supply box S2 via the short tube JP, this power supply box S
2 is also filled with inert gas or reducing gas, and power supply box S3 is also filled with coaxial busbar PB4, short
An inert gas or a reducing gas is supplied through the JP and the gas is filled.

Therefore, once the wire W enters the power supply box S2, it travels to the power supply box S3 without being exposed to the outside air.

In this way, in this embodiment, there is no opportunity for the wire W to come into contact with the outside air between the power supply boxes S2 and S3, where the wire temperature is in the high temperature range, so even if the wire W has a high degree of oxidation promotion in the high temperature range, , oxidation can be reliably prevented.

[Effect of idea]

As explained above, in this invention, between the power supply boxes where the wire temperature is in the high temperature range, the inside of both power supply boxes is filled with inert gas or reducing gas, and the wire feeding path between both power supply boxes is filled with inert gas or reducing gas. Since it is completely wrapped in gas, it is possible to reliably prevent oxidation even if the wire W has a high degree of oxidation promotion in the high temperature range, and can be used as a simple oxidation prevention method between power supply boxes where the wire temperature is in the low temperature range. Therefore,
The above effects can be obtained without using an excessive amount of antioxidant means.

[Brief explanation of drawings]

FIG. 1 is a partially sectional front view showing an embodiment of the present invention. C...Contact roll, E...Heating power supply, B
...Plate busbar, In...Gas inlet, JP...
Short tube, P...Pipe line, PB1-PB4...Coaxial busbar, S1-S3...Power supply box, T...Joint, X...Connection terminal, W...Wire.

Claims (1)

[Claims for Utility Model Registration] A power supply box comprising first and second power supply boxes each containing a pair of contact rolls that are sequentially arranged at a predetermined interval in the wire feeding direction and a heating power source, and comprising a heating power supply and a contact roll of both power supply boxes. first and second plate-shaped busbars in which a power supply circuit for supplying power to the rolls extends from the heating power source to a predetermined position on the wire feeding path;
A first coaxial busbar having a tubular shape coaxial with the wire feeding path and having both ends connected to the connection terminal of the first power supply box and the first busbar, and a second coaxial busbar having both ends connected to the first busbar.
In a device consisting of a second coaxial busbar which is connected to the connection terminal of a power supply box and a second busbar and forms a tube coaxial with the wire feed passage, a third coaxial busbar disposed downstream of the second power supply box A power supply box, a second heating power source that supplies power to the contact rolls built into the second and third power supply boxes, one end of which is connected to the second power supply box, and the other end of which is connected to the second power supply via a third plate busbar a third coaxial busbar connected to the heating power supply, one end connected to the third coaxial busbar;
The power supply box is equipped with a fourth coaxial busbar and a gas supply source whose other end is connected to a third heating power source via a fourth plate-shaped busbar, and the third coaxial busbar and the fourth coaxial busbar are supplied with power. The box side ends open into the corresponding power supply boxes via insulating short tubes, and the mutually opposing ends of both coaxial busbars are connected by an insulating tubular joint, and this joint and the first and second coaxial busbars are A wire energization heating device characterized in that each gas inlet has a gas inlet, and each gas inlet is connected to a gas supply source of an inert gas or a reducing gas through piping.