JP2006324081A - Sheet heater and manufacturing method of heating element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet heater without increasing manufacturing cost; and to provide a manufacturing method of a heating element used for the sheet heater. <P>SOLUTION: A strip-like thin plate formed of a resistive member is so formed that linear parts 22 are positioned between meandering parts 21 by appropriately partially cutting it from both right and left sides. The positions of the meandering parts 21 are allowed to be changed by folding back the linear parts 22 when it is arranged in an insulation sheet 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet heater in which a heating element made of a resistance member having flexibility is sandwiched by an insulating sheet member from above and below, and a method for manufacturing the heating element used in the sheet heater.

  A conventional seat heater of this type is formed by sandwiching a heating element in which a resistor is formed in a meandering shape with an insulating sheet member from above and below.

  A heating element used in such a sheet heater is formed by forming an appropriate meandering-shaped covering layer on the surface of a planar resistance member and dissolving and removing a portion where the covering layer is not formed by etching. (For example, refer to Patent Document 1).

Or the mask layer from which the meandering shape part was extracted is formed in the surface of one insulating sheet member, and the resistance material is made to adhere to the extracted part by vapor deposition (for example, patent document 2). reference).
JP-A-10-22065 (paragraphs 0003 and 0013) Japanese Patent Laid-Open No. 10-321348 (paragraph 0002)

  In the method of manufacturing a heating element by etching or vapor deposition as disclosed in the above-mentioned patent document, it takes a long time to dissolve and remove unnecessary portions by etching, or to deposit a resistive material until a required thickness is obtained. Cost. In addition, the coating layer and mask layer must be formed as a dedicated product in accordance with the shape of the heating element to be manufactured, and cannot be diverted when manufacturing heating elements of other shapes. Is significantly higher.

  Furthermore, in order to manufacture a large-sized resistor, an etching tank and a vapor deposition furnace large enough to contain the resistor are required, so that the cost of the manufacturing apparatus increases dramatically as the size of the resistor increases. To do.

  Then, this invention makes it a subject to provide the manufacturing method of the heat generating body used for the seat heater which does not raise manufacturing cost, and a seat heater in view of said problem.

  In order to solve the above problems, a sheet heater according to the present invention is a sheet heater in which a heating element formed by bending a flexible thin plate-like resistance member in a meandering shape is sandwiched from above and below by an insulating sheet member. A plurality of meandering parts formed in a meandering shape are formed on the body, and a straight line part for connecting two meandering parts to each other is provided between the meandering parts. The extending directions of the two meandering portions connected to each other are different.

  According to the above configuration, the extending directions of the meandering parts adjacent to each other can be made different by folding the straight part, so that the position of the meandering part can be appropriately selected. Increased freedom.

  This seat heater can be used, for example, for melting snow for a communication parabolic antenna. However, when electromagnetic waves are emitted from the seat heater, the parabolic antenna receives the noise. In this case, an electromagnetic wave shielding layer for preventing leakage of electromagnetic waves from the heating element may be formed over almost the entire surface of the insulating sheet member.

  A conductive ceramic film may be deposited on the surface of the heating element. As this ceramic, for example, indium tin oxide (ITO) can be used.

  In order to solve the above problems, a heating element manufacturing method according to the present invention is a heating element manufacturing method for manufacturing a heating element by forming a meandering portion having a meandering shape on a flexible thin plate-like resistance member. The member is formed in a band shape in advance, and a meandering portion is formed by cutting out part of the resistance member alternately left and right along the longitudinal direction of the resistance member from both side edges of the band-shaped resistance member.

  In addition, the strip-shaped resistance member is wound in a roll shape in advance, and while cutting out the resistance member at a predetermined pitch, a part of the resistance member is cut out alternately on the left and right along the longitudinal direction of the resistance member. A predetermined number of pitches can be fed without being cut off, and then a straight portion connecting the two meandering parts in the front and back can be formed in the portion that has been fed by the distance.

  As is clear from the above description, the seat heater according to the present invention can change the extending direction of the meandering portion by folding back the straight portion connecting the meandering portions, so that the shape of the seat heater can be changed. By changing the folded state of the straight portion, the meandering portion can be matched with the changed shape of the seat heater, and the degree of freedom of the shape of the seat heater can be increased. And the manufacturing cost of a seat heater can be reduced by increasing the degree of freedom in this way.

  In addition, the heating element manufacturing method according to the present invention is not a conventional method such as etching or vapor deposition, but a heating element suitable for the sheet heater is manufactured by a method in which a part of the resistance member is cut off. It can be greatly reduced.

  Referring to FIG. 1, reference numeral 1 denotes a seat heater according to the present invention. The seat heater 1 is manufactured by sandwiching a heater 2 as a heating element between two insulating sheets from above and below. The heater 2 is composed of four meandering portions 21 and straight portions 22 that interconnect the meandering portions. Then, power supply lead wires 12 are connected to both ends of the heater 2. As described above, the heater 2 is formed of a thin plate which is a stainless steel resistance member having a thickness of about 50 μm. In the present embodiment, indium tin oxide is deposited on the surface of the heater 2 to a thickness of 0.1 μm. In addition, after sandwiching the heater 2 between the insulating sheets 11, a coating material that shields electromagnetic waves was applied to the surface of the insulating sheet 11.

  First, the heater 2 is formed so that the four meandering portions 21 and the straight portion 22 are sequentially arranged on one straight line, and the four meandering portions 21 are mutually connected by folding the straight portion 22 as shown in the figure. Arranged to be parallel.

  Referring to FIG. 2, when one meandering portion 21 is fixed and the meandering portion 21 adjacent to the fixed meandering portion 21 is rotated 180 degrees counterclockwise without being turned over in the illustrated state, the linear portion 22 is It is folded twice at 90 degrees, resulting in the state shown in FIG. In addition, the linear part 22 becomes double in the vicinity of the turned-back part 22a, and the part where the linear part 22 contacts each other arises. Then, since the current is short-circuited at the contact point, there is a risk of spark discharge. Therefore, the insulating piece 31 is sandwiched so that the double linear portions 22 near the folded portion 22a do not contact each other.

  In the case shown in FIG. 2, as described above, the meandering portion 21 is rotated 180 degrees counterclockwise. However, when the meandering portion 21 is rotated 180 degrees counterclockwise, that is, as shown in FIG. In this case, since the folding direction of the two folded portions 22a is reversed, two insulating pieces 32 are used and inserted in the vicinity of each folded portion 22a.

  As shown in FIG. 4, the heater 2 used for the seat heater 1 is manufactured by processing a strip-shaped resistance member 4. The resistance member 4 is wound in a roll shape, and is supported so that the central shaft 41 is held by a stand 42 and can be pulled out freely.

  Then, the roll-shaped resistance member 4 is drawn linearly, and the meandering portion 21 and the straight portion 22 are formed by the processing device 5. Referring to FIG. 5, the processing apparatus 5 includes a die 51 located below the resistance member 4. A pair of punching blades 6R and 6L are held above the die 51 so as to be movable in the vertical direction with the resistance member 4 interposed therebetween. A punching hole 52 is formed in the die 51 so as to face the punching blades 6R and 6L.

  Accordingly, when the punching blades 6R and 6L are lowered while the resistance member 4 is placed on the upper surface of the die 51, a part of the resistance member 4 is cut from the left and right sides of the resistance member 4 by the punching blades 6R and 6L.

  Note that the blade portions of the punching blades 6R and 6L have a wave-blade shape. By making the wave blade shape in this way, the plurality of leading protrusions from which the blade portions protrude first bite into the resistance member 4 to position the resistance member 4. Therefore, the position of the resistance member 4 does not shift in the process of cutting out a part of the resistance member 4.

  A pair of cutting blades 7R and 7L are provided downstream of the punching blades 6R and 6L so as to oppose left and right with respect to the feeding direction. In this cutting, 7R and 7L can move in the vertical direction similarly to the cutting blades 6R and 6L, and a cutting hole 55 is formed in the die 51 corresponding to both the cutting blades 7R and 7L. Reference numerals 53 and 54 denote transport rollers.

  Referring to FIG. 6, (a) in this figure shows a straight portion 22 formed on the right side with respect to the feeding direction, and (b) shows a straight portion 22 formed on the left side with respect to the feeding direction. Show.

  In what is shown to (a), the extraction blades 6R and 6L are lowered simultaneously, and the meandering part 21 is formed. The resistance member 4 is sent one pitch at a time. In the case of forming the straight portion 22, the punching blades 6R and 6L are not lowered, but are fed by one pitch, and further fed by one pitch, and only the punching blade 6L is lowered. And the linear part 21 is formed in the feed direction right side by lowering the cutting blade 7L twice for every pitch to the part fed idle.

  In (b), only the punching blade 6R is lowered at the position where the straight line portion 22 is formed, and then 1 pitch is fed forward. And the linear part 22 is formed in the feed direction left side by dropping the cutting blade 7L by 2 pitches, that is, twice.

  The outer surfaces 7Ra and 7La of the cutting blades 7R and 7L were curved so as to be convex outward. As a result, for example, when a part of the resistance member 4 is cut by the cutting blade 7L to form the straight portion 22, even if the cutting blade 7L is lowered twice, it is moved twice as shown in the enlarged view of FIG. The cut line of the cut portion that intersects does not cross, leaving no cut-off residue.

  In the case shown in FIG. 1, the shape of the seat heater 1 is formed in a rectangular shape. However, as shown in FIG. 7, the seat heater 8 may be formed in an annular shape. In this case, the insulating sheet 81 is formed in an annular shape, and the heater is sandwiched between the two insulating sheets 81. At that time, the curved portion 21 was laid out almost radially by turning the straight portion 22 located on the center side once instead of twice.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

The figure which shows the structure of one embodiment of this invention The figure which shows the return state in the straight line part The figure which shows the other return state in a straight part The figure which shows the layout at the time of processing of a resistance member Diagram showing the configuration of the processing equipment The figure which shows the formation process of a straight part Diagram showing another shape of seat heater

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sheet heater 2 Heater 4 Resistance member 5 Processing apparatus 8 Sheet heater 21 Meandering part 22 Linear part 22a Folding part

Claims (5)

  In a sheet heater in which a heating element obtained by forming a flexible thin plate-like resistance member in a serpentine shape is sandwiched from above and below by an insulating sheet member, a plurality of serpentine portions formed in a serpentine shape are formed in the heating element. In addition, a linear portion that connects the two meandering portions to each other is provided between the meandering portions, and by folding the straight portion, the extending directions of the two meandering portions that are connected to both ends of the linear portion are determined. A seat heater characterized by being made different.   The sheet heater according to claim 1, wherein an electromagnetic wave shielding layer for preventing leakage of electromagnetic waves from the heating element is formed over substantially the entire surface of the insulating sheet member.   The seat heater according to claim 1 or 2, wherein a conductive ceramic coating is deposited on the surface of the heating element.   In a heating element manufacturing method for manufacturing a heating element by forming a meandering portion having a meandering shape on a flexible thin plate-shaped resistance member, the resistance member is formed in a strip shape in advance, and both sides of the strip-shaped resistance member are formed. A method of manufacturing a heating element, wherein a meandering portion is formed by cutting out a part of a resistance member alternately left and right along the longitudinal direction of the resistance member from an edge. A strip-shaped resistance member is wound in advance in a roll shape, and a part of the resistance member is cut out alternately and right and left along the longitudinal direction of the resistance member while feeding out the resistance member at a predetermined pitch. 5. The method of manufacturing a heating element according to claim 4, wherein a linear portion for connecting two front and rear meandering portions to each other is formed at a portion that is idled for a predetermined number of pitches, and thereafter the portion that is idly fed.

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