JP2006147286A - Matrix heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a matrix heater especially suitable for pre-heating a heat transfer foil of an inmold system since it can give temperature gradient and temperature distribution intentionally on a surface of a workpiece. <P>SOLUTION: The matrix heater is characterized in that it is configured by arranging a plurality of heater elements on a base, respective temperatures of which can be controlled independently. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a matrix heater formed from an assembly of a plurality of heating elements, and can intentionally impart a temperature gradient and temperature distribution to the object to be heated, for preheating the transfer foil of a simultaneous molding printing system. It is related with a suitable matrix heater.

  Conventionally, a heater having a heating element and a substrate on which the heating element is held is well known (for example, Patent Document 1). In such a heater, heating elements made of ceramic or the like are arranged on an insulating base material, and the entire surface of the object to be heated is uniformly heated by bringing the object to be heated into contact therewith.

  However, for example, when a conventional heater is used for preheating the transfer foil in a simultaneous molding transfer printing system (transfer printing is performed in a mold simultaneously with product molding), the following problems may occur. . That is, in transfer printing for printing on a three-dimensional curved surface, the transfer foil is generally preliminarily heated in order to improve the contact property of the transfer foil with the curved surface. Since the entire surface of the transfer foil is heated uniformly, the entire transfer foil is heated, and the entire foil expands, and there is a possibility that the positioning accuracy of the transfer foil and consequently the transfer printability may be deteriorated.

Therefore, in order to prevent the above-mentioned adverse effects, prevent breakage of the transfer foil on a more complicated three-dimensional curved surface, etc., and improve the transfer printability by closely attaching the transfer foil to the positioning accuracy, A heater capable of partially heating the surface of the transfer foil, which is an object, is desired.
Japanese Patent Laid-Open No. 2002-050657

  An object of the present invention is to provide a matrix heater that can intentionally impart a temperature gradient and temperature distribution to the surface of an object to be heated, and is suitable for preheating a transfer foil of a simultaneous molding printing system, for example. The inventor named the heater according to the present invention as a matrix heater, in particular, in order to distinguish the heater according to the present invention from the conventional heater.

  In order to solve the above-mentioned problems, the matrix heater according to the present invention comprises a plurality of heating elements that are independently temperature-controllable on a substrate. In such a configuration, since the plurality of heating elements can be independently controlled in temperature, the heating temperature of each heating element can be arbitrarily set and adjusted. Therefore, a desired temperature gradient and temperature distribution can be given to the object to be heated. In addition, only the portions of the object to be heated that are separated from each other can be heated by one matrix heater.

  The heating element can be arbitrarily arranged depending on the direction of application of the temperature gradient to the object to be heated. However, if the heating elements are arranged in a grid, the direction and size of the temperature gradient can be set almost arbitrarily. it can.

  The heating element includes at least a heating element. The heating element is not particularly limited, and examples thereof include a ceramic heater and a bare heating wire heater in which a bare wire is wound around a core wire.

  Select a material with a relatively high resistance temperature coefficient (for example, 1,000 ppm / ° C. to 5,000 ppm / ° C. is preferable) as a heating wire material of a heating element such as a ceramic heater, and generate a weak current when no current is applied. It is also possible to indirectly measure the temperature of the heating element by flowing the voltage and measuring the voltage drop. In this case, it is desirable to provide a non-energization time for the temperature measurement at an interval of 10 mS to 500 mS.

  In order to prevent the tendency of temperature uniformity due to mutual heat interference between the heating elements, it is preferable to provide a mechanism for cooling the entire heating elements while minimizing the thermal coupling between the heating elements as much as possible.

  Examples of the base material include insulators such as polyimide, heat-resistant polyethylene terephthalate, glass fiber, silicone, and heat-resistant rubber.

  The matrix heater according to the present invention can intentionally give a desired temperature gradient and temperature distribution to an object to be heated. In addition, only the portions of the object to be heated that are separated from each other can be heated by one matrix heater. Therefore, it can be used in a wide range of industrial fields, but it is particularly suitable for preheating the transfer foil in a simultaneous molding printing system that performs transfer printing on the surface of the molded product simultaneously with the molding of the molded product.

  Since the matrix heater as described above is configured such that a plurality of heating elements can be controlled independently of each other, a temperature gradient and a temperature distribution can be intentionally given to the object to be heated. In addition, only one portion of the object to be heated can be heated by one matrix heater.

  Preferred embodiments of a matrix heater according to the present invention will be described below with reference to the drawings. 1 and 2 show a matrix heater according to an embodiment of the present invention. In the figure, reference numeral 1 denotes a matrix heater. The matrix heater 1 has a base material 2. A plurality of heating elements 3 are provided on the substrate 2. In this embodiment, the heating elements 3 are arranged in a lattice pattern. Each heating element 3 has a ceramic heater 4 as a heating element. A temperature sensor 5 that detects the temperature of the ceramic heater 4 is provided in the heating element 3. The ceramic heater 4 is fixed on the base material 2 by a fixing material 17 (for example, a silicone material). Each ceramic heater 4 and each temperature sensor 5 are connected to temperature control means 6. An insulating sheet-like member 18 is provided on the surface of the ceramic heater 4, that is, on the contact surface side of the object to be heated. In this embodiment, the ceramic heater 4 is fixed on the base material 2 by the fixing material 17, but is fixed on the base material 2 by the legs 20 made of a conductive material for energization as shown in FIG. It is also possible. In the configuration as shown in FIG. 3, the fixing material 17 is eliminated, the thermal coupling between the ceramic heaters 4 is reduced as much as possible, and the entire ceramic heaters 4 can be cooled. Can be reliably prevented.

  The temperature control means 6 is configured to be able to input a set temperature for each heating element 3. And the temperature control means 6 is comprised so that each ceramic heater 4 may be turned on / off based on the temperature detected by each temperature sensor 5. FIG. Therefore, the temperature of each heating element 3 is controlled independently of each other.

  In addition, a material having a relatively large temperature coefficient of resistance (for example, 1,000 ppm / ° C. to 5,000 ppm / ° C. is suitable) is selected as the heating wire material of the ceramic heater 4, and a weak current is allowed to flow when not energized. The temperature of the ceramic heater 4 can be indirectly measured by measuring the voltage drop. In this case, it is desirable to provide a non-energization time for the temperature measurement at an interval of 10 mS to 500 mS.

  In the present embodiment, since the plurality of heating elements 3 are configured to be independently temperature-controllable, the heating temperature can be arbitrarily set and adjusted between the respective heating elements. Therefore, a desired temperature gradient and temperature distribution can be given to the object to be heated. In addition, only the portions of the object to be heated that are separated from each other can be heated by one matrix heater.

  Moreover, in this embodiment, since each heating element 3 is arranged in a grid | lattice form, a temperature gradient and temperature distribution can be set substantially arbitrarily.

  FIG. 4 shows a simultaneous molding printing system 7 in which the matrix heater 1 is used for preheating the transfer foil. The simultaneous molding printing system 7 includes a mold 8 and a transfer foil feeding unit 11. The mold 8 is attached to an injection molding machine (not shown), and includes a fixed mold 9 and a movable mold 10. The transfer foil feeding means 11 has a supply reel 12 and a take-up reel 13. The transfer foil 14 is made of polyethylene terephthalate (PET) having a thickness of about 40 to 50 μm, and transfer portions 15 are provided in the longitudinal direction of the transfer foil 14 at a predetermined interval. Then, when the supply reel 12 and the take-up reel 13 are driven at the same time, the transfer foil 14 is fed out by a certain amount, so that the transfer portion 15 on the transfer foil 14 enters the cavity (not shown) of the mold 8. It is designed to be aligned. The position of the transfer unit 15 in the cavity is adjusted by image processing using a CCD camera, for example. The alignment is performed by detecting the displacement of the alignment marker 19 provided at the end in the width direction of the transfer foil 14.

  In such a simultaneous molding printing system, the transfer foil feeding means 11 is driven to align the transfer portion 15 with the cavity. Then, a resin is filled into the cavity from the molding machine, and a molded product (not shown) is molded. At the same time, the pattern on the transfer portion 15 is transferred and printed on the surface of the molded product by heat on the molded product side immediately after molding.

  Further, in such a simultaneous molding printing system, when the transfer foil feeding means 11 is driven and the transfer portion 15 is aligned with the cavity, the transfer portion 15 of the transfer foil 14 is preheated by the matrix heater 1. It has become. The matrix heater 1 is moved in the arrow direction at the timing when the molded product take-out machine takes out the molded product, and preliminarily heats the transfer unit 15. The preheating temperature can be arbitrarily set, but is set to 100 to 200 ° C. in the system of FIG.

  Since the matrix heater 1 is configured such that the plurality of heating elements 3 can be independently controlled in temperature, the matrix heater 1 is heated by intentionally imparting a temperature gradient and temperature distribution to the transfer portion 15 that is the object to be heated. it can. For example, even when the transfer portions 15 are separated in the width direction of the transfer foil 14 (in the case of simultaneous molding of a large number), only the transfer portions 15 separated from each other by one matrix heater 1 can be heated. . Therefore, expansion deformation due to heating of portions other than the transfer portion 15 of the transfer foil 14 is prevented, so that the positional accuracy of each transfer portion 15 does not deteriorate. In addition, when it is possible to improve the finish of transfer printing on a molded product by forming a predetermined temperature gradient in the transfer unit 15 and preheating it, the transfer unit 15 is heated by applying a predetermined temperature gradient. It is also possible to do. In addition, the plurality of heating elements 3 are configured to be independently temperature-controllable, and the set temperature of each heating element 3 can be easily changed in response to the shape of the molded product. It has.

  The matrix heater according to the present invention can heat an object to be heated by applying a predetermined temperature gradient, for example, and can efficiently heat only the separated parts of the object to be heated with one matrix heater. Therefore, it can be applied in a wide range of industrial fields, but is particularly suitable for preheating the transfer foil of a simultaneous molding printing system.

It is a schematic block diagram of the matrix heater which concerns on one embodiment of this invention. It is a partial expanded sectional view of the matrix heater of FIG. It is a partial expanded sectional view of the matrix heater of the aspect different from FIG. It is a schematic block diagram of the simultaneous molding printing system using the matrix heater of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Matrix heater 2 Base material 3 Heating element 4 Ceramic heater 5 Temperature sensor 6 Temperature control means 7 Molding simultaneous printing system 8 Mold 9 Fixed mold 10 Movable type 11 Transfer foil feeding means 12 Supply reel 13 Take-up reel 14 Transfer foil 15 Transfer Part 17 Fixing material 18 Sheet-like member 19 Marker 20 Leg part

Claims (7)

  A matrix heater, wherein a plurality of heating elements capable of independent temperature control are arranged on a substrate.   The matrix heater according to claim 1, wherein the heating elements are arranged in a lattice pattern.   The matrix heater according to claim 1, wherein the heating element has at least a heating element.   The matrix heater according to claim 3, wherein the heating element is a ceramic heater.   The matrix heater according to claim 3 or 4, comprising a function of estimating a temperature by measuring a change in a resistance value of the heating element using a non-zero resistance temperature coefficient of the heating element.   6. A mechanism for reducing the thermal coupling between the heating elements as much as possible and cooling the entire heating elements in order to prevent the tendency of temperature uniformity due to mutual heat interference of the heating elements. A matrix heater according to any one of the above. The heater according to any one of claims 1 to 6, wherein the heater is a heater for preheating the transfer foil in a simultaneous molding printing system.

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