JP2002100458A - Heating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating system which does not cause thermal degradation of a heating element, efficiently radiating infrared rays to a heating object, and capable of quickening a temperature rising speed of the heating object. SOLUTION: In this heating system for juxtaposing plural heating element units, composed of a bar-like heating element 1 having a light nontransmissive surface and radiating infrared rays from the surface and a gutter-shaped reflecting mirror 2 for surrounding the heating element 1, the heating system is characterized in that an area X facing a top part T of the heating element 1 of the reflecting mirror 2 becomes an infrared-ray diffusing part 21, so as not to reflect the infrared ray radiated from the heating element 1 to the heating element 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating apparatus used for heating a synthetic resin sheet to be heated when manufacturing a synthetic resin container for packaging food.

[0002]

2. Description of the Related Art Conventionally, foods sold at convenience stores and the like are sold in disposable synthetic resin containers. This synthetic resin container, for example, conveys a single synthetic resin sheet of 100 cm in length and 100 cm in width below the heating device or between heating devices arranged above and below, and receives infrared rays radiated from the heating device. Heating the entire synthetic resin sheet substantially uniformly, and then, with the synthetic resin sheet at a high temperature, sandwiching both sides of the synthetic resin sheet with a molding member and molding the molded article into a packaging container of a specific shape by pressing or vacuuming. It is.

FIG. 10 is a sectional explanatory view of a conventional heating device used in such a process. The heating device B is a ceramic heater having a bottom portion 30, a side portion 31, and an upper portion 32 integrally formed of ceramics and having a space 4 therein and a polygonal cross section. The bottom 30 facing the synthetic resin sheet has a planar shape, and a nichrome wire or a Kanthal wire is buried inside the bottom 30 as a heating element 33. Generates heat, and this heat is transmitted to the ceramics constituting the bottom portion 30 to heat the ceramics, and infrared rays are emitted from the ceramics to heat the synthetic resin sheet. Reference numeral 5 denotes a pair of power supply lines, which are introduced into the inside of the ceramic heater via a relay section 6 provided on the upper portion 32, and the ends of which are connected to the heating element 33. A plurality of the heating devices B are arranged to heat the entire synthetic resin sheet of a predetermined size substantially uniformly.

[0004]

However, as shown in FIG. 10, such a heating device B emits infrared rays also in a direction opposite to the synthetic resin sheet (upward in FIG. 10), and efficiently uses the infrared rays. There was a problem that was not. As a result, the temperature of the synthetic resin sheet could not be raised in a short time.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a heat-generating body that does not undergo thermal deterioration, efficiently emits infrared rays to a synthetic resin sheet to be heated, An object of the present invention is to provide a heating device capable of increasing a heating speed.

[0006]

According to a first aspect of the present invention, there is provided a heating apparatus, comprising: a rod-shaped heating element having a surface that is opaque and emitting infrared rays from the surface; and a gutter-shaped reflecting mirror surrounding the heating element. In the heating device in which a plurality of heating element units are arranged, an area of the reflecting mirror facing the top of the heating element is configured to prevent infrared rays emitted from the heating element from being reflected by the heating element. It is characterized by being.

A heating device according to a second aspect of the present invention is the heating device according to the first aspect, wherein the infrared diffusing portion of the reflecting mirror is convex toward the heating element. Features.

The heating device according to a third aspect is the heating device according to the first aspect, wherein the infrared diffusing portion of the reflecting mirror is an opening provided in the reflecting mirror. .

The heating device according to the fourth aspect is characterized in that:
4. The heating device according to claim 3, wherein the heating element has a filament disposed along a pipe axis inside the tubular valve, and an infrared radiation member on a surface of the tubular valve. 5. Characterized in that the heater lamp is coated with ceramics.

[0010]

Embodiments of the present invention will be described.
FIG. 1 is a sectional view of a heating device according to the present invention.
Is a heating element unit a having a rod-shaped heating element 1 whose surface is opaque and emitting infrared rays from the surface, and an aluminum gutter-shaped metal reflecting mirror 2 surrounding the heating element 1.
Are arranged side by side.

FIG. 2 is a sectional view showing only the heating element unit a of the heating device A shown in FIG. 1. As shown in FIG. 2, the reflecting mirror 2 is composed of a synthetic resin sheet as an object to be heated. A region X facing the top T of the opposite side of the heating element 1 serves as an infrared diffusing section 21 for preventing infrared rays emitted from the heating element 1 from being reflected back to the heating element 1. The top T of the heating element 1 refers to a part of the heating element 1 on the reflecting mirror side that intersects the optical axis Y of the reflecting mirror 2 as shown in FIG. As shown in FIG. 2, a region X of the reflecting mirror 2 facing the top T of the heating element 1 is parallel to the optical axis Y of the reflecting mirror 2 and coincides with the maximum outer diameter of the heating element 1. It refers to a part of the reflecting mirror 2 existing between the virtual lines Z.

2, the infrared diffusing portion 21 is a part of the reflecting mirror 2 indicated by a dotted line for convenience, and is formed in a region X facing the top T of the heating element 1. . In addition, as shown in FIG. 3, from the viewpoint of workability and accuracy of the reflecting mirror 2, the infrared diffusing portion 21 may be formed beyond the region X facing the top T of the heating element 1 of the reflecting mirror 2. In this case, the ratio of the infrared diffusing portion 21 to the entire reflecting mirror 2 depends on the relationship between the infrared ray radiated from the heating element 1 and the infrared ray reflected by the reflecting mirror 2 on the object to be heated. There is no problem as long as the ratio of the infrared rays to be emitted does not significantly decrease.

That is, the infrared diffusing portion 21 of the reflecting mirror 2
The infrared rays emitted from the heating element 1 are not reflected back to the heating element 1 and are not returned.

Specifically, as shown in the cross-sectional view of FIG. 4, the heating element 1 has a filament 12 arranged along a tube axis inside a tube valve 11 made of quartz glass. Ceramics 13 which is an infrared radiation member on the surface of
Is a coated heater lamp. That is, in this heater lamp, since the ceramic 13 is coated on the surface of the tubular bulb 11, the surface of the tubular bulb 11 becomes opaque, and the visible light radiated from the filament 12 is transmitted to the tubular bulb 11. Ceramics 1 coated on the surface of 11
3 is converted into infrared light and emitted.

The other heating element 1 may be a sheathed heater as shown in the sectional view of FIG. In this sheathed heater, a nichrome wire 15 as a resistance heating element is disposed inside a stainless steel tube 14 that emits infrared rays, and an insulator 16 made of magnesium oxide is provided in a gap between the nichrome wire 15 and the metal tube 14. The metal tube 14 is filled and sealed at both ends with a sealing member 17 made of an insulating material. The power supply pin 18 penetrates the sealing member 17 and is electrically connected to the internal nichrome wire 15. . That is, also in this sheathed heater, the surface of the metal tube 14 is opaque.
4 emits infrared rays from the surface.

When the heating element 1 is a heater lamp or a sheathed heater, as shown in the sectional view of FIG. 6, the shape of the reflecting mirror 2 is a parabola having a sectional shape perpendicular to the longitudinal direction of the reflecting mirror 2. In the case of a shape or an ellipse (not shown), the infrared rays reflected from the reflecting mirror 2 are returned to the surface of the heating element 1 on the reflecting mirror 2 side indicated by a dotted line for convenience. The surface temperature of the heating element 1 rises abnormally. Therefore,
It has been found that when the heating element 1 is a heater lamp, a problem occurs in that the ceramics 13 coated on the surface of the tubular bulb 11 deteriorates. When the heating element 1 is a sheathed heater, the insulator 16 is oxidized or a nichrome wire is used. It has been found that a problem arises in that the temperature of the sample No. 15 rises above the allowable temperature and melts.

On the other hand, in order to solve such problems of the heater lamp and the sheathed heater, the input power of the heater lamp and the sheathed heater is reduced so that the infrared light reflected by the reflecting mirror 2 can be used in the tubular lamp 11 in the heater lamp. It is conceivable to reduce the amount of reflection itself on the surface of the metal tube 14 in the case of the sheathed heater or the sheathed heater. It has been found that a problem arises in that the temperature cannot be raised.

In order to solve such a problem, according to the present invention, as shown in FIG. 2, infrared rays emitted from the heating element 1 are reflected on the heating element 1 by an infrared diffusing portion 21 of the reflecting mirror 2. As a result, when the heating element 1 is a heater lamp, the ceramic is not thermally degraded. When the heating element 1 is a sheathed heater, the insulator surrounding the nichrome wire is not oxidized and the nichrome wire is blown. do not do. In addition, the input power of the heater lamp or the sheathed heater can be increased, and the amount of infrared radiation emitted to the object to be heated can be increased.

As shown in FIGS. 1 and 2, portions other than the infrared diffusing portion 21 of the reflecting mirror 2 efficiently capture the infrared radiation radiated from the heating element 1 and apply the infrared radiation to the synthetic resin sheet to be heated. Is efficiently reflected, so that the object to be heated can be heated to a predetermined temperature in a short time. Further, since the structure is such that infrared rays are not reflected from the reflecting mirror 2 to the heating element 1, the input power of the heating element 1 can be increased, so that the object to be heated can be heated to a predetermined temperature in a shorter time. .

FIG. 7 is an explanatory view of another embodiment of the heating unit constituting the heating device of the present invention.

In FIG. 7, an opening 22 is provided in a region X of the reflecting mirror 2 facing the top T of the heating element 1, and this opening 22 is an infrared diffusing portion 21 indicated by a dotted line for convenience. That is, the infrared diffuser 21 diffuses the infrared radiation emitted from the heating element 1 to the rear of the reflecting mirror 2.

That is, the infrared diffusing section 21 of the reflecting mirror 2 shown in FIG. 7 has a structure in which the infrared rays reflected from the reflecting mirror 2 are not reflected back to the heating element 1.

Next, a reflecting mirror provided with an infrared diffusing portion in a region opposed to the top of the heating element which is a heating element unit constituting the heating device of the present invention shown in FIG. 2 and a sectional shape shown in FIG. FIG. 8 shows experimental data comparing the temperatures at the tops of the heating elements of the respective heating devices when using a reflecting mirror which is object-shaped and does not have an infrared diffusing portion in a region facing the tops of the heating elements. . The heating element used in this experiment was the heater lamp shown in FIG. 4, which was turned on at a rated voltage of 200 V and 400 W and measured the temperature of the ceramics coated on the top surface of the tubular bulb.

FIG. 8 shows the lighting time (seconds) on the horizontal axis and the temperature of the ceramics coated on the top surface of the tubular valve on the vertical axis. As is clear from FIG. 8, both the heating device of the present invention having an infrared diffusing portion in the reflecting mirror and the heating device having no infrared diffusing portion in the reflecting mirror have a brightness of 10% after lighting.
Although the temperature of the ceramics becomes constant in 0 second, the stable temperature of the ceramics is about 730 ° C. as shown in the graph B in the heating device having no infrared diffusing portion in the reflecting mirror. If it is used for a long time, thermal degradation such as cracking or peeling off of ceramics occurs.
On the other hand, in the heating device of the present invention, the stable temperature of the ceramic is about 630 ° C. as shown in graph A, and the temperature of the ceramic can be lowered by about 100 ° C. as compared with the conventional heating device, and the ceramic does not crack. Does not peel off. Note that ceramics sufficiently emit infrared rays even at 630 ° C.

That is, in the heating device of the present invention, since the reflecting mirror is provided with the infrared diffusing portion, the infrared light is not reflected back to the surface of the tube-shaped bulb of the heater lamp. Not go up, so
It can emit infrared rays stably for a long time.

Further, the input power of the heater lamp can be increased and the amount of infrared radiation radiated from the heater lamp can be increased within a range where the ceramic is not thermally degraded. The temperature can be raised to the temperature.

FIG. 9 shows the heating device of the present invention shown in FIG.
11 is experimental data showing a temperature rise state of a synthetic resin sheet as an object to be heated when the conventional ceramic heater shown in FIG. 10 is used. The heating element of the heating device of the present invention has a rating of 200
V, 400 W, the heater lamp shown in FIG. 4 in which the surface of the tubular bulb is coated with ceramics. Conventional ceramic heaters are also rated at 200V and 400W. In the heating device of the present invention, the distance between the surface of the tubular valve and the synthetic resin sheet is made equal to the distance between the bottom and the synthetic resin sheet in the conventional ceramic heater, and the synthetic resin sheet is kept at room temperature (25 ° C.). The experiment was conducted in a state in which the temperature was raised from the heated state.

FIG. 9 shows the time (seconds) on the horizontal axis and the temperature (° C.) of the synthetic resin sheet on the vertical axis. The temperature is raised to 160 ° C., which is the temperature at which the synthetic resin sheet can be deformed. In the conventional ceramic heater, it took 37 seconds as shown in graph B, but in the heating device of the present invention, as shown in graph A, it was as short as 27 seconds, and the synthetic resin sheet was heated to a predetermined temperature in a short time. It can be seen that it can be warmed. This is because infrared rays are efficiently captured by the reflecting mirror, and the captured infrared rays are efficiently reflected on the synthetic resin sheet.

[0029]

According to the heating device of the present invention, the reflecting mirror surrounding the heating element has a region opposed to the top of the heating element on the side opposite to the object to be heated, and the infrared radiation radiated from the heating element is applied to the heating element. Since it is an infrared diffusing section for preventing reflection and return, there is no occurrence of thermal deterioration of the heating element.

In addition, the portion other than the infrared diffusing portion of the reflecting mirror is configured to efficiently capture the infrared radiation radiated from the heating element and efficiently reflect the infrared light to the object to be heated. The temperature can be raised to a predetermined temperature in a short time. Further, since the infrared ray is not reflected from the reflecting mirror to the surface of the heating element, the input power of the heating element can be increased, and the object to be heated can be heated to a predetermined temperature in a shorter time.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a heating device of the present invention.

FIG. 2 is a diagram illustrating a heating unit according to the present invention, which includes a heating element and a reflecting mirror.

FIG. 3 is an explanatory diagram of a heating unit according to the present invention, which includes a heating element and a reflecting mirror.

FIG. 4 is an explanatory diagram of a heater lamp which is a heating element of the heating device of the present invention.

FIG. 5 is an explanatory diagram of a sheath heater which is a heating element of the heating device of the present invention. It is.

FIG. 6 is an explanatory diagram of a heating element unit including a heating element and a reflecting mirror having no infrared diffusing portion in the reflecting mirror.

FIG. 7 is an explanatory diagram of a heating unit according to the present invention, the heating unit including a heating element and a reflecting mirror.

FIG. 8 is an explanatory diagram of experimental data comparing the temperatures at the tops of the heating elements of the heating device of the present invention and the conventional heating device.

FIG. 9 is an explanatory diagram of experimental data showing a temperature rise state of a synthetic resin sheet as a heating target when the heating device of the present invention and a conventional ceramic heater are used.

FIG. 10 is an explanatory sectional view of a conventional heating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating element 2 Reflecting mirror 21 Infrared diffusing part 21a Diffusing surface 21b Diffusing surface 22 Opening

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3K058 AA02 AA22 BA00 CE02 CE12 CE16 CE17 CE31 EA03 3K092 PP20 QA01 QA02 QB02 QB27 QC18 QC37 RA01 RA03 RB04 RC01 RC16 RD03 RD11 SS32 SS47 TT37 VV16 VV28 VV31 A58 MA01 MA02 MB01 MH06 MK08

Claims (4)

[Claims] 1. A heating device in which a plurality of heating element units each including a rod-shaped heating element whose surface is opaque and radiating infrared rays from the surface and a gutter-shaped reflecting mirror surrounding the heating element are arranged. A heating device, wherein an area of the reflecting mirror facing the top of the heating element is an infrared diffusion section for preventing infrared rays emitted from the heating element from being reflected by the heating element. 2. The heating device according to claim 1, wherein the infrared diffusing portion of the reflecting mirror is convex toward the heating element. 3. The heating device according to claim 1, wherein the infrared diffuser of the reflector is an opening provided in the reflector. 4. The heating element according to claim 1, wherein the heating element is a heater lamp in which a filament is arranged inside a tube-shaped bulb along a tube axis, and the surface of the tube-shaped bulb is coated with a ceramic material serving as an infrared radiation member. The heating device according to claim 1, wherein the heating device is a heating device.