JP2006261095A - Planar heater device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a planar heater device excelling in responsiveness, and capable of preventing a material loss, and obviating the need of a special correction structure for preventing drift. <P>SOLUTION: In this planar heater device 2, a plurality of heating surfaces 41 of a heating wire are arranged in parallel with one another on the surface of a support plate 3 by winding the single ribbon-like heating wire 4 on the support plate 3. The support plate 3 is so structured that ridge-shaped uneven parts 31a are repeatedly formed at pitches P at one of parallel sides thereof opposite to each other; and ridge-shaped uneven parts 31b having the same shapes are repeatedly formed at the same pitches P on the other of the parallel sides by shifting them by 1/2 pitch. By winding the single ribbon-like heating wire 4 along ridge-shaped slope faces of the ridge-shaped uneven parts 31a, and by arranging it between the ridge-shaped uneven parts 31a and 31b on both the sides opposite to each other as shown in Fig., the heating surfaces 41 of the ribbon-like heating wire 4 are set parallel with the surface of the support plate 3, and the plurality of the heating surfaces 41 are arranged in parallel with one another on the support plate surface. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an improvement in a planar heater device having excellent heat generation response.

  Conventionally, when a resin plate having a large area is heated in manufacturing a resin molded part or the like, various planar heater devices have been used. For example, there is a planar heater device in which many ceramic embedded far-infrared heaters in which a heating wire is embedded in a ceramic body are arranged. Such a ceramic-embedded far-infrared heater is excellent in durability because the heating wire is not exposed to the outside, but since the heat capacity of the heater itself is large, until it reaches a predetermined temperature after energization Since a considerable amount of time is required, the responsiveness is inferior, which is inappropriate for intermittent heating operation. In addition, there is a problem that it takes time until the temperature falls to a safe temperature range even if the current is cut off in an emergency.

  As such a planar heater with improved responsiveness, there is a planar heater in which a heating plate of a reciprocating pattern is formed by etching or press punching a thin metal plate for a heater of a predetermined material such as iron nickel or nickel chrome. is there. An example of this planar heater device is shown in FIG. 13. This heater device 1 is formed by forming a thin metal heater material into a heat generating portion 11 of a reciprocating pattern by the above-mentioned means, and its folded portion 12. Is fixed to the heater support plate 2 with fixing screws 21, and the reciprocating pattern 11 also has energization terminals 13, 13 at both ends.

In such a heater device, since the heat capacity of the device can be reduced, the responsiveness is greatly improved. However, since a part of the heater metal thin plate is removed, a material loss occurs. In addition, the etching or punching process itself causes high costs, and the whole is expensive. In addition, when there is variation in the electric resistance value of the material, there is a problem that the heater resistance value can hardly be adjusted. There were problems such as the need to add a correction structure.
Japanese Patent Publication No. 45-017947: Claims Japanese Patent Laid-Open No. 2001-126847: Claims 1, 1 and 14

  The present invention has been made to solve the above problems, and is a planar heater that can achieve excellent responsiveness, prevent material loss, and eliminate the need for the correction structure corresponding to drift. Providing equipment.

  The above problem is that the surface of the present invention comprises a sheet heater in which a ribbon-like heating wire is wound around a support plate and the heating plate has a heating surface arranged in parallel on the support plate surface. This can be solved by the heater device. According to the present invention, this planar heater is formed by repeatedly forming chevron irregularities on one side of the opposite side of the support plate and repeatedly forming the same chevron irregularities shifted by 1/2 pitch on the other side. A ribbon-shaped heating wire is wound around the chevron slope, and is laid between chevron irregularities on both sides facing each other, the heating surface of the ribbon-shaped heating wire is parallel to the support plate surface, and the support plate surface It is preferable that a plurality of the heating surfaces are arranged in parallel on the top.

Furthermore, in the present invention, the support plate is preferably a non-water-absorbing electrical insulating material made of a mica plate or an alumina plate, and the shape thereof is a frame-like plate provided with a space penetrating front and back. preferable.
More preferably, a frame member for fixing the outer peripheral surface is mounted on the surface of the support plate on which the ribbon-like heating wires are arranged. Moreover, it is more preferable that the case for housing and fixing the support plate on which the ribbon-like heating wire is disposed has a reinforcing structure.
Furthermore, it is preferable to have a structure in which a frame member having a ribbon-shaped heating wire hanging prevention piece is attached to the front surface of the planar heater, and the temperature control thermocouple is placed on the upper surface of the ribbon-shaped heating wire of the planar heater. A structure in which the tip is directly spot welded can also be used.

  Thus, the planar heater device of the present invention is excellent in responsiveness because the exposed ribbon heater is used. Further, since a sheet heater is formed by winding a single ribbon-like heating wire, there is an advantage that no material loss occurs at all. In addition, since a single ribbon-like heating wire is wound around and used as a heater, there is no partial current bias, so that the above-described correction structure is unnecessary. Therefore, the present invention has an extremely large industrial value as a planar heater device that has solved the conventional problems.

Next, an embodiment according to the planar heater device of the present invention will be described with reference to FIGS.
The feature of the sheet heater device of the present invention is that a sheet heater 2 in which ribbon-like heating wires 4 illustrated in FIG. 1 are arranged in a plurality of rows is used, and one ribbon is provided on the support plate 3. The point is in the planar heater 2 in which a plurality of heat generating surfaces 41 of the heat generating wire are arranged in parallel on the surface of the support plate 3 around the surface heating wire 4.

  More specifically, in the present invention, the support plate 3 having the shape shown in FIG. 2 is used to wind one ribbon-like heating wire 4. This support plate 3 is formed by repeatedly forming chevron irregularities 31a on one side of the parallel opposite sides with a pitch P, and repeatedly forming chevron irregularities 31b having the same shape shifted by 1/2 pitch on the other sides at the same pitch P. It is.

  Then, as shown in FIG. 3, one ribbon-like heating wire 4 is wound along the mountain-shaped slope 32a of the mountain-shaped unevenness 31a, and as shown in FIG. 31a and 31b), the heating surface 41 of the ribbon-like heating wire 4 is parallel to the surface of the support plate 3, and a plurality of the heating surfaces 41 are arranged in parallel on the support plate surface. It is preferably arranged.

  Here, the ribbon-like heating wire 4 is drawn out from the end portions 42 and 42 and connected to an input terminal (not shown). In this embodiment, it is preferable that the angled slope 32a has an inclination angle of 45 degrees. The support plate 3 has four fixing holes 33 on the outer periphery.

  The planar heater device of the present invention has the planar heater 2 described above as a main member, and a member configuration example is shown in FIG. In FIG. 4, in the case 51 with a square frame, the planar heater 2 is housed and disposed with the heat generating surface 41 facing the surface and the fixing hole 33 screwed to the mounting bracket 52. The required power is supplied from the input terminals 53 and 53. Further, here, the case 51 with a square frame preferably has a reinforcing structure composed of a bent portion such as a constricted portion 51a by a press in order to alleviate deformation due to radiant heat from the heating wire.

  Furthermore, when the frame member 54 for fixing the outer peripheral surface of the sheet heater 2 to the frame shape is attached to the surface of the sheet heater 2 and both end portions of the heat generating surface 41 are pressed, the sheet heater 2 is installed downward. In this case, it is more preferable because the heat generating surface 41 can be prevented from sagging. The frame member 54 is preferably made of sintered alumina ceramic because of its heat resistance and electrical insulation.

  Further, supplementing the support plate 3 used in the present invention, it is preferable to use a non-water-absorbing electrical insulating material such as a mica (mica) plate or a sintered alumina plate as the material. The thickness is 1 mm to 5 mm depending on the surface size. As the shape thereof, as illustrated in FIG. 5, if a frame-like plate provided with a large number of circular hole spaces 34 (FIG. 5A) penetrating the front and back and a space 35 (FIG. 5B) that passes through the center, Since the heat capacity of the support plate itself is further reduced, the advantage that the temperature responsiveness is further improved is obtained, which is preferable.

  Needless to say, the planar heater device of the present invention is excellent in responsiveness because it is used with the ribbon-like heating wire exposed as described above. For example, as shown in FIG. 6, in the ceramic embedded far-infrared heater, as shown in the temperature curve A, the saturation temperature is not reached even after 3 minutes from the start of energization, but in the planar heater device of the present invention, the temperature curve As shown in B, a high responsiveness of reaching the saturation temperature after about 10 seconds is obtained.

  As described above, since excellent responsiveness can be obtained in the present invention, in the case of intermittent heating, heating efficiency can be increased and power loss in the heating process can be reduced. Further, since a sheet heater is formed by winding one ribbon-like heating wire, a special advantage that no material loss of the heating material occurs is obtained. In addition, since there is no change in the cross-sectional area in the reciprocating and folding parts of the heating surface, unlike the conventional heater, there is no partial current bias, so there is no material deterioration, so the conventional correction structure is also available The advantage that it is unnecessary is also obtained.

  In the embodiment described above, the outer peripheral portion of the planar heater 2 is pressed by the rectangular frame member 54 as shown in FIG. 4, but the ribbon-like heating wire 4 is thermally expanded during use of the heater, and the heating surface is When facing downward, the central part may hang down. Therefore, as shown in FIGS. 7 and 8, the frame member 54 attached to the front surface of the planar heater 2 is provided with a sag prevention piece 55 of the ribbon-like heating wire 4, and the sag prevention piece 55 is a ribbon-like heat generation. As shown in FIG. 9, it is preferable to have a partition wall structure 56 on the inner surface as shown in FIG. 9 and prevent the central portion of the planar heater 2 from sagging so that the wires cannot contact each other. The number of the sag prevention pieces 55 is not necessarily one, but if the number is increased, the heat generating surface is shielded. Therefore, it is preferable that one sag prevention piece 55 is provided at the center part that is most likely to sag as shown in the figure.

  In addition, a thermocouple for detecting the temperature and controlling the output is attached to the planar heater device of the present invention, but in the case of a conventional planar heater, an insulating cylindrical body is attached and the inside thereof is installed. It was common to insert and fix the tip of a thermocouple. However, as shown in FIGS. 10 and 11, the ends of the two metal wires constituting the thermocouple 60 are crossed, and spot welding is directly performed on the upper surface of the central portion of the ribbon-like heating wire 4, thereby simplifying the structure. Cost can be reduced.

  Now, this type of planar heater device is generally 125 mm × 125 mm and has a calorific value of 570 to 580 W per piece, which is a de facto standard. The conventional product has a limit in winding density, and in order to adjust the heat generation amount per unit area to the above-mentioned restrictions, the voltage was reduced to about 30 V with a transformer and the current was supplied.

  However, the planar heater device of the present invention employs a special ribbon-like heating wire 4 winding structure as described above, so that the resistance value per unit area determined by the winding density is higher than that of the conventional product. Even if it is operated at a voltage of 50V, the above restrictions can be met. Therefore, as shown in FIG. 12, it is possible to employ an operation method in which four planar heater devices are connected in series and an industrial power supply voltage of 200 V is applied to both ends thereof. If such a method is adopted, there is no need to install a transformer as in the prior art, and the cost can be greatly reduced. In addition, since the width | variety adjustable width | variety of the planar heater apparatus of this invention is large, not only 4 series connection but 2 series connection or 6 series connection is always possible. It is a great advantage of the present invention that such a method of use is possible.

The front view of the planar heater for demonstrating the planar heater apparatus of this invention. The front view which shows the support plate of this invention. The principal part perspective view of a support plate and a heating wire for explaining the winding state of a heating wire. The front view (A) and side view (B) which show the planar heater apparatus of this invention. The front view which shows the other form (A) (B) of the support plate of this invention. The graph which shows the responsiveness of this invention. It is sectional drawing which shows other embodiment of this invention. It is a front view which shows other embodiment of this invention. It is the top view which shows the inner surface of a frame member, and its AA sectional drawing. It is sectional drawing which shows the attachment structure of a thermocouple. It is the top view and side view which show the attachment structure of a thermocouple. It is a top view which shows the four series connection state of the planar heater apparatus of this invention. The front view which shows the conventional planar heater apparatus.

Explanation of symbols

2: planar heater 3: support plate, 31a, 31b: chevron irregularities, 32a, 32b: chevron slope 4: ribbon-shaped heating wire, 41: heating surface

Claims (8)

  A planar heater device comprising a sheet heater in which a ribbon-shaped heating wire is wound around a support plate and the heating plate has a heating surface parallel to the heating plate surface.   The planar heater repeatedly forms chevron irregularities on one side of the opposite side of the support plate, and repeatedly forms the same chevron irregularities shifted by 1/2 pitch on the other side, and one ribbon-like heating wire Winding along the chevron slope, and erected between chevron irregularities on both sides facing each other, the heating surface of the ribbon-shaped heating wire is parallel to the support plate surface, and the heating surface is on the support plate surface The planar heater device according to claim 1, wherein a plurality of the heaters are arranged in parallel.   The planar heater device according to claim 1 or 2, wherein the support plate is a non-water-absorbing electrical insulating material made of a mica plate or an alumina plate.   The planar heater device according to claim 3, wherein the support plate is a frame-shaped plate provided with a space penetrating front and back.   The planar heater device according to claim 2, 3 or 4, wherein a frame member for fixing an outer peripheral surface is mounted on a surface of the support plate on which a ribbon-like heating wire is disposed.   The planar heater device according to any one of claims 2 to 5, wherein a case for housing and fixing the support plate on which the ribbon-like heating wire is disposed has a reinforcing structure.   The planar heater device according to any one of claims 2 to 6, wherein a frame member including a ribbon-shaped heating wire sag prevention piece is attached to the front surface of the planar heater.   The planar heater device according to any one of claims 2 to 7, wherein a front end portion of a thermocouple is directly spot-welded to an upper surface of a ribbon-like heating wire of the planar heater.

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