JPH04100651A - Coiling machine - Google Patents

Abstract

PURPOSE:To prevent a filament wire from being cut, flawed or cracked by blowing a high-temp. nonoxidative gas to the filament wire just before the wire is wound around a mandrel by means of a heat gun, then winding the filament wire in a slightly hardened state without oxidizing the wire. CONSTITUTION:The filament wire 1 consisting of a tungsten strand is drawn out of a spool 2 and is passed through a nozzle 3, by which the winding set thereof is corrected. The front end of this wire is chucked to the mandrel 4 and the mandrel 4 is rotated. The nozzle 3 is simultaneously fed at a prescribed speed along the axial line direction of the mandrel 4 to form the coiled filament 5. An ejection port 61 of the heat gun 6 is disposed between the nozzle 3 and the mandrel 4 at this time and is moved together with the nozzle 3. The high- temp. nonoxidative gas G is blown from the ejection port 61 to the filament wire 1 just before the wire is wound around the mandrel 4 to heat the filament wire 1 to the high temp. without oxidizing the wire. The filament wire is thus wound in the slightly hardened state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a coiling machine for producing a coiled filament to be placed in the bulb of a tubular incandescent lamp.

[Prior art and its problems]

Tubular incandescent light bulbs have a coiled filament arranged along the tube axis of the bulb, and the coiled filament is manufactured using a coiling machine. In other words, the filament wire is drawn out from the spool, fed out from a nozzle, and wound around a rotating mandrel. Alternatively, the nozzle may be wound by rotating it around a stationary mandrel. This filament wire is, for example, a tungsten wire with a wire diameter of about 0.12 to 0.41 mmφ, but when it is wound around a mandrel, it is processed into a coil shape with a small radius of curvature while applying a large tension. Therefore, the degree of processing is large, and the filament wire may be scratched or cracked, and in some cases, the wire may break. Particularly in winter, wires with a diameter of 0.25 mm or more are easily broken, scratched, or cracked when wound around a thin mandrel.

Further, when winding is completed and the tension applied to the filament wire is released, the diameter of the filament increases and the overall length increases due to springback, causing the problem that the dimensions of the filament become out of order.

[Purpose of the invention]

Therefore, the present invention has developed a coiling machine that prevents the filament wire from breaking, causing scratches, or cracks when winding the filament wire around a mandrel, suppresses springback, and obtains filament with accurate dimensions. The purpose is to provide

[Structure of the invention and its operation]

The structure of the present invention is a coiling machine that manufactures a coiled filament by winding a filament wire pulled out from a spool around a mandrel, and in which a high-temperature non-oxidizing gas is applied to the filament wire just before it is wound around the mandrel. It is characterized by the provision of a spraying heat gun.

That is, since the filament wire is sprayed with a non-oxidizing gas such as high-temperature inert gas or nitrogen gas at a temperature of about 150°C to the filament wire just before it is wound around the mandrel using a heat gun, the filament wire is somewhat softened without being oxidized, and it can be used in winter. Even when a filament wire with a large wire diameter is wound around a thin mandrel with a large processing degree, wire breakage and scratches can be prevented.

Also, springback is reduced and filaments with accurate dimensions can be obtained.

〔Example〕

Embodiments of the present invention will be specifically described below based on the drawings.

In FIG. 1, a filament wire 1 made of a tungsten wire with a wire diameter of about 0.12 to 0.41 m++φ is wound around a spool 2, pulled out from the spool 2, and passed through a nozzle 3. A tension applying mechanism (not shown) is arranged between the spool 2 and the nozzle 3. Furthermore, when the filament wire 1 is pulled out from the spool 2, it has curls and is curled.
Straightening mechanism with rows of rollers arranged in a staggered manner (not shown)
The curled filament wire 1 is passed through this straightening mechanism to straighten the curl. Nozzle 3
The tip of the filament wire 1 fed out from the mandrel 4
When the mandrel 4 is rotated and the nozzle 3 is fed at a predetermined speed along the axial direction of the mandrel 4, a coiled filament 5 is formed.

Here, the ejection port 61 of the heat gun 6 is arranged between the nozzle 3 and the mandrel 4, and moves together with the nozzle 3. The heat gun 6 is connected to a non-oxidizing gas cylinder such as inert gas or nitrogen gas, and is covered with a heater 62.

Then, this non-oxidizing gas G is heated to about 150° C., and the high-temperature non-oxidizing gas G is sent from the jet port 61 to the mandrel 4.
It is sprayed onto the filament wire 1 just before it is wound.

Therefore, the filament wire 1 is heated to a high temperature without being oxidized, and is wound in a somewhat softened state. Therefore, even if the filament wire 1 with a large wire diameter is wound around a thin mandrel 4 with a large degree of processing in winter, scratches and cracks can be prevented, and the wire will not break. When released, springback is reduced and dimensionally accurate filaments can be obtained.

〔Effect of the invention〕

As explained above, the coiling machine of the present invention.

Since non-oxidizing gas at a high temperature of, for example, about 150° C. is sprayed onto the filament wire just before it is wound around the mandrel using a heat gun, the filament wire is wound in a somewhat softened state without being oxidized. Therefore, even if a filament wire with a large diameter is wound around a thin mandrel with a large degree of processing in the winter, the filament wire will not break, scratch or crack, and springback can be suppressed to ensure accurate dimensions. filament can be obtained.

[Brief explanation of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

Claims (1)

[Claims] A coiling machine that manufactures a coiled filament by winding a filament wire pulled out from a spool around a mandrel, wherein the filament wire is heated with a high-temperature non-oxidizing gas just before being wound around the mandrel. A coiling machine characterized by being equipped with a heat gun that sprays.