JPH02174087A - Ring-shaped heating body - Google Patents

Abstract

PURPOSE:To attempt to solve the problem of uneven heating and uneven light emission in the circumferential direction of a glass tube by mutually crossing both ends of the glass tube and then arranging a heating filamentary coil received in the tube so as to reach the intercrossed end portions, while extending the head of each of both ends of the tube to a region outside a portion enclosed with the ring-shape of the glass tube for being led out of the tube. CONSTITUTION:A glass tube 1 made of quartz glass has both ends thereof crossed mutually in the upper and lower directions thereof, and then extensions 10, 10 extended from these intercrossed end portions are bilaterally symmetrized mutually, and is extended along the tangential direction of the ring-shaped line of the tube from each of the intercrossed end portions. Besides, a filamentary coil 2 received in the glass tube 1 is arranged continuously from the crossed portion of one-end extension 10 to the crossed portion of the other-end extension 10 within this glass tube 1. The heating filamentary coil received in the glass tube 1 is accordingly arranged to reach the intercrossed end portions of the tube for being arranged over about the whole circumference of the ring-shaped line. This makes it possible to solve the problem of uneven heating and uneven light emission in the circumferential direction of the tube.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to an annular heating element used as a heater or as a light source.

(Prior art) For example, an annular infrared lamp used as a heater for an electric kotatsu or a cooking appliance has a tube 1 made of heat-resistant glass such as quartz glass or hard glass, as shown in FIG. It is bent into a substantially annular shape and is placed inside this glass tube 1 along the tube axis.

A heating wire, for example, a filament coil 2 made of tanzosten, is housed therein. This filament coil 2
is supported on the tube axis of the glass tube 1 by a holder 3 consisting of a plurality of ring anchors spaced apart in the axial direction.

Both ends of the glass tube 1 are located on an annular line and are opposed to each other, separated from each other, and each of these ends is crushed and sealed. Metal foil conductors 5.5 made of molybdenum MO or the like are sealed to these crushing sealing parts 4. A lead wire 6.6 and an external lead wire 7.7 connected to an external power source are connected.

In such an annular infrared lamp, when the external lead wire 7.7 is connected to a power source, the filament coil 2 is energized and the filament coil 2 generates heat, so that it functions as an annular heater.

(Problems to be Solved by the Invention) Incidentally, in the annular infrared lamp as described above, both ends of the glass tube 1 are located on an annular line and are opposed to each other and spaced apart from each other.

That is, if both ends of the glass tube 1 are close to each other, the other end will get in the way during the sealing operation of the crush sealing part, and the mount containing the filament coil 2 may not be inserted into the glass tube 1 through this end. If the other end is too close to each other when the other end is inserted into the housing, it will interfere with the insertion operation, and for this reason, the distance between the crushing seals 4.4 is relatively large.

However, if the distance between the crushed sealing parts 4 and 4 is large as described above, there is no filament coil in this spaced area, so no heat is generated, the temperature is lower than other parts, and the temperature is lower in the circumferential direction along the annular shape. There is a problem that causes variations in heat distribution.

Further, the crushing sealing parts 4, 4 are located on the annular line, and this position is relatively close to the heat generation area by the filament col 2, that is, the zone surrounded by the annular shape. 4 tends to rise in temperature, so there is a concern that leaks may occur early, and there are also problems that may lead to a shortened lifespan.

In particular, in the case of cooking appliances, the annular infrared lamp used as the heater may be surrounded by a heat insulating material 9 for the purpose of improving thermal efficiency, central heating, and thermal protection of the equipment. In this case, the temperature of the area surrounded by the heat insulating material 9 increases, and therefore the temperature rise of the sealing parts 4, 4 located on the annular line becomes even higher; Cracks occur and leaks occur, resulting in a shortened lifespan.

In the present invention, variations in the heat generation distribution or light emission distribution along the circumferential direction of the annular shape are eliminated, and in the case of a device equipped with a crushing sealing part, the temperature rise of the crushing sealing part is reduced, leakage is prevented, and the service life is extended. The purpose is to provide a ring-shaped heating element.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention has a method in which both ends of a glass tube are crossed with each other and a heating wire housed in the tube is arranged at least up to the crossing point, Further, the tube is characterized in that the tip portions at both ends of the tube are extended and led out beyond the portion surrounded by the annular shape of the glass tube.

(Function) According to the present invention, the heat-generating wire housed in the glass tube can be arranged at least up to the intersection of the tubes, so the heat-generating wire is arranged over substantially the entire circumference of the annular line. Variations in heat generation and light emission in the circumferential direction are eliminated. In addition, in the case of a device that forms a crushing seal, the tip where the crushing seal is formed is extended and led out beyond the part surrounded by the annular shape, so it is away from the heat generating area, and therefore Temperature rise in the crushed sealing part is suppressed, the occurrence of leaks due to cracks is reduced, and the life is extended.

(Example) The first example of the present invention will be described below in FIGS. 1 and 2.
This will be explained based on the diagram.

This example is a 200V heater used as a cooker heater.
A 2KW type annular infrared lamp is shown, and parts that may be the same as conventional ones are given the same numbers and explained. In the figure, 1 is a glass tube made of quartz glass with a tube outer diameter of 11 mm and a ring outer diameter of 150 mm. In this embodiment, it is bent into a substantially perfect ring shape. This glass tube 1 crosses each other by crossing over in the vertical direction at both ends, and extension portions 10 extending from these crossing points.
Reference numeral 10 is symmetrical and extends from the intersection along the tangential direction of the annular line.

Note that the extension portion 10 of this embodiment. The derived length g of lO is
It is about 50 dragons from the intersection.

The tungsten filament coil 2 housed in the glass tube 1 is arranged continuously within the glass tube 1 from the intersection of one extension 10 to the intersection of the other extension 10. , a holder 3 consisting of a plurality of ring anchors spaced apart in the axial direction, etc.
is supported on the tube axis of the glass tube 1. Internal lead wires 6°6 are connected to both ends of the filament coil 2, and these internal lead wires 6,
6 is guided in said extension 10.10.

Each of the extension parts 10 and 10 has a crushing sealing part 4 at its tip.
．． 4 are formed, and metal foil conductors 5, 5 made of molybdenum Mo or the like are sealed to these crushing sealing parts 4, 4. These metal foil conductors 5, 5 are connected to the internal lead wire 6.
6 and an external lead wire 7.7 connected to an external power source.

The operation of such a first embodiment will be explained.

When the external lead wires 7, 7 are connected to 'si, the filament coil 2 is energized, and the filament coil 2 generates heat, so that it functions as an annular heater.

In this case, the filament coil 2 is continuously arranged in the glass tube 1 from the intersection of one extension 10 to the intersection of the other extension IO, so that the filament coil 2 is arranged continuously around the entire circumference of the annular line. Therefore, the heat generation distribution becomes uniform over the entire circumference.

Further, the extension portions 10.10 are extended from the intersection along the tangential direction of the annular line, and the crush sealing portions 4, 4 are formed at the tips of these extension portions 10.10, respectively. , 4 will be located outside the annular line. Therefore, it moves away from the heat generating area of the filament coil 2 and is less likely to be affected by heat from the filament coil 2.

Therefore, the temperature rise in the crushing sealing parts 4, 4 is reduced, and the thermal expansion of the metal foil conductor 5.5 is small, so that the crushing sealing parts 4.4
leaks are less likely to occur. This results in a longer lamp life.

Note that when such an annular infrared lamp is surrounded by a heat insulating material 9, extensions 10.10 are formed in the lamp. Insulate the tip of the to
It can be led out of the heat insulating material 9 through a lead-out hole 11.11 formed in.

In this way, the temperature of the inside surrounded by the heat insulating material 9 will rise due to the heat generated by the filament coil 2, and this heat will be prevented from escaping to the outside by the heat insulating material 9, so thermal efficiency will be improved and concentrated heating will be possible. It becomes possible.

In this case, the extension 10.10 becomes a conductor for the heat insulating material 9, and the temperature rise is extremely well suppressed. therefore,
No cracks occur, leaks are prevented, and the lifespan is significantly extended.

In the case of the above embodiment, the glass tube I is bent into a substantially perfect ring shape, and an extension part 1 (1
, 10 are shown as extending along the tangential direction of the annular line from the intersection, but the present invention is not limited to this.

That is, in the second embodiment shown in FIG. 3, the glass tube 20 has an irregular annular shape that is bent into a substantially oval shape, and the extensions 21 and 21 extend in the radial direction from the annular line. There is.

Further, in the third embodiment shown in FIG. 4, the glass tube 30 has an irregular annular shape bent into a substantially rectangular shape, and the extension portions 31 and 31 extend diagonally across the annular lines. There is.

Even in these second and third embodiments, the same effects as in the first embodiment can be achieved.

Furthermore, in each embodiment, an infrared lamp, that is, a lamp used as a heater, has been described, but the present invention can also be implemented with a lamp having this type of structure used as a light source, for example, a tungsten wire filament coil. It can be applied to decorative lamps that utilize the light emitted from heat generation.

In addition to the tungsten wire filament coil, the heating wire may be a nichrome wire used as a heat source.

Therefore, the glass tube is not limited to having both ends hermetically sealed, but may be capped with a cap or the like to be electrically connected to the outside air.

Furthermore, the glass tube may be made of quartz glass, hard glass, or soft glass.

[Effects of the Invention] As explained above, according to the present invention, the heating wires housed in the glass tube are arranged at least up to the intersection, so the heating wires are arranged over almost the entire circumference of the annular line. This has the advantage that variations in heat generation and light emission in the circumferential direction are eliminated.

In addition, for example, in the case where a crushing seal is formed at the end, the tip with the crushing seal is extended outward from the part surrounded by the annular shape, so it can be moved away from the heat generating area. Therefore, the temperature rise of the crushed sealing portion is suppressed, the occurrence of leakage due to cracks is reduced, and the life is extended.

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the present invention, FIG. 1 is a plan view, FIG. 2 is a side view, and FIGS. 3 and 4 are second and third embodiments of the present invention, respectively. FIG. 5 is a plan view showing the conventional structure. 1, 20.30...Glass tube, 2...Filament coil, 4...Crushing sealing part, 5...Metal foil conductor, 6...Internal lead wire, 7...External lead wire ,
10.21゜31...extension part. Applicant's representative Patent attorney Takehiko Suzue

Claims (1)

[Claims] In an annular heating element in which a glass tube is bent into an annular shape and a heating wire is housed inside the annular glass tube along the tube axis, both ends of the glass tube are crossed with each other and inserted into the tube. An annular heating element characterized in that the housed heating wire is disposed at least up to this intersection, and the tips at both ends of the tube are extended and led out beyond the part surrounded by the annular shape of the glass tube.