The present invention relates to a structure of a heating head mounted on a fax machine, printer, etc.
as
FIG. 1 shows a heating head, a driver IC 3 for selectively generating heat generated by the heating resistor 2 is mounted on an insulated heating resistor substrate 1, on which a line of heating resistors and electrodes for supplying power to it are disposed on, and a flexible circuit board 4 is electrically connected to the driver integrated circuit (IC) 3 for transmitting electrical signals for operation control and providing power by an external circuit. Usually the flexible circuit board 4 is electrically connected to the electrode connection terminal of the heating resistor substrate by means of soldering and other means to achieve electrical connection. In addition, the heating resistor is fixed to a heat dissipation plate 5 with a substrate 1 and a flexible circuit board 4 for optimal dissipation of the heat generated by the heating resistor 2.
Figures 3 and 4 show an example of the structure of a conventional heating head. By using a double-sided (tape) tape or adhesive, the heating resistor is fixed to the heat sink plate 5 with a substrate 1 and a flexible circuit board 4. However, when the heat dissipation plate 5 forms a stepped part structure, if it is fixed with a double-sided (tape) tape or adhesive, it is difficult to evenly paste or cover the double-sided (tape) tape or adhesive on the entire surface of the heat dissipation plate in a single operation. In particular, when adopting a structure with a stepped part, it is not possible to apply the adhesive by adopting a printing system. As described above, the principle lies in that one side of the heat sink plate 5 for fixing the heating resistance substrate 1 and the flexible circuit board 4 is a flush surface without a stepped part, therefore, as shown in FIG. 3, the step difference between the flexible circuit board 4 and the heat dissipation plate 5 due to the thickness difference of the heating resistance substrate 1 requires to be processed by pasting a substrate 6 with a thickness consistent with the step difference relative to the flexible printed board 4. However, according to this method, the manufacturing cost of the flexible circuit board 4 is significantly increased, so this method is difficult to adopt.
FIG 4 shows the structure of a heat dissipation plate 5 forming a stepped portion. According to this structure, the heat dissipation plate 5 forms a step difference, therefore, when using double-sided (tape) tape for fixing operation, the double-sided (tape) tape is pasted on the heat dissipation plate for the operation of pasting the part of the substrate 1 for the heating resistance, and the double-sided (tape) tape is pasted on the heat sink plate 5 for pasting the part of the flexible circuit board 4 must be performed separately. In addition, in the case of adhesives, as mentioned above, printing systems cannot be used, but a coating system such as a brush or a spray system such as a distributor can be used, so it is not only cumbersome to operate, but also difficult to achieve uniform application.
A method is provided according to the actual list in FIG. 4, wherein for the portion of the flexible circuit board 4 for pasting the heat sink plate 5, the double-sided (tape) tape is pre-pasted on the side of the flexible circuit board 4. In this case, although the cost is not as high as the structure of plate 6 corresponding to the thickness of the ladder difference as described above, the increase in cost is inevitable considering that a large number of operation steps are required when it is necessary to remove the paper to be peeled in the double-sided (tape) tape.
Therefore, in the example shown in FIGS. 3 and 4, due to the increase in the cost of the flexible circuit board 4, or the complexity of the steps of applying double-sided (tape) tape or the process of applying adhesive, are factors that lead to the increase in the manufacturing cost of the heating head.
Object of the present invention is to provide a very inexpensive heating head structure and manufacturing method thereof, wherein the increased cost of flexible circuit board or heat dissipation board, simply and conveniently double-sided (tape) tape is attached to the heat dissipation plate or the adhesive is applied to the heat dissipation plate.
According to the present invention, one side of the heat sink plate for fixing the heating resistance substrate and the flexible circuit board is composed of a flush surface, and the flexible circuit board is bent and fixed to the heat dissipation board.
By adopting the above structure, there is no need to fix the substrate used to compensate for the step difference to the flexible circuit board, nor to attach double-sided (tape) tape to it. In addition, double-sided (tape) tapes can be applied or applied to a straight surface in a single operation.
FIG 1 is a cross-sectional view of the structure according to the present invention; FIG 2 is a cross-sectional view of a partial section of the structure of the present invention; Figure 3 is a cross-sectional view of a conventional example; Figure 4 shows a cross-sectional view of a conventional example.
An embodiment of the present invention will be explained below.
First, explain the situation when using double-sided (tape) tape. One side of the substrate 1 and the flexible circuit board 4 for pasting the heating resistor on the heat sink plate 5 is a flush surface without step difference, so a double-sided (tape) tape is pasted on the side in the area consistent with the width used to paste the two substrates. In this case, only the paper used for peeling in the double-sided (adhesive) tape needs to be peeled off, and for this purpose, the double-sided (tape) tape must be pressed against the heat dissipation plate by applying a certain force, so the bonding surface uses an extruder or the like to rub and press. In this case, according to the conventional structure, a stepped structure is provided on the surface of the heat sink, and not only must an extruder with a specific shape be used to evenly squeeze the double-sided (tape) tape on the entire surface of the pasted part, but it is also difficult to bond the tape to the stepped part of the heat sink without forming an air gap.
When using an adhesive, the adhesive is applied to the same portion of the heat dissipation pole that is the same as the area used for the double-sided (tape) tape. This is best done using screen printing, in which case it can be applied very simply, easily and evenly. As mentioned above, in the case of a structure with a stepped part on the surface of the heat dissipation plate, it cannot be coated by a screen printing system, and the screen printing system can only be applied when the heat dissipation plate is straight.
The heating resistor substrate 1 and the flexible circuit board 4 are connected to each other in advance by soldering, etc. The heating resistance substrate 1 and the flexible resistance plate 4 are bonded to the heat sink plate 5 using the double-sided (adhesive) tape described above, and the heating resistance substrate 1 and the flexible circuit board 4 form an extrusion contact with the heat sink plate 5.
In this case, although the flexible circuit board 4 is bent as shown in FIG. 1, usually although the substrate is bent to this extent, it does not pose a problem such as disconnecting the wiring at all. At the same time, the flexibility of this flexible part can be further improved by adopting a flexible circuit board with a structure as shown in Figure 2. Typically, the substrate comprising a double-sided lead of the first conductor 7, an insulating layer 8 and a second conductor 9 is used as a circuit board for the heating head. In this example, the flexible portion consists only of a first conductor layer 1. By using this flexible circuit board, both performance and reliability are improved.
In addition, the main trend of conventional heat dissipation plate materials is the extruded material of metallic aluminum. Even for heat sinks with stepped part shapes, it is relatively convenient to manufacture. However, in recent years, iron plates have been used as this material, which is cheaper than aluminum. The iron plate belongs to such a shape of the board, its two sides are straight, so when the stepped part of the heat sink plate 5 shown in FIG. 4 is attached to the part of the heat sink plate 5 for pasting the flexible circuit board 4 as described above, it is necessary to bend. In this case, the cost increases even when less expensive materials are used, so it is important to make the shape of the heat sink flush surface and without step difference.
According to the present invention, the double-sided (tape) tape can be simply and conveniently pasted on the heat dissipation plate or the adhesive coated on the heat dissipation plate, without the use of a flexible circuit board or heat dissipation board that increases the cost, therefore, a very cheap heating head can be manufactured.
Claims
1. A heating head comprising a substrate for a heating resistor, comprising a plurality of heating resistors and a driver integrated circuit (IC) for selectively heating each heating resistor on the insulated substrate; a flexible circuit board connected to a substrate for heating resistors for power supply to the driver integrated circuit; A heat dissipation board, heating resistance substrate and flexible resistance plate are fixed to the base; and wherein, one side of the heat sink plate used to fix the substrate for heating resistance and one side of the heat sink board used to fix the flexible circuit board constitute a flush surface, and the flexible circuit board is fixed to the heat sink board by bending the flexible circuit board.
2. The heating head according to claim 1, wherein the flexible circuit board comprises a plurality of conductive layers respectively placed between the various insulating layers, and the larger conductor at the flexible portion of the flexible circuit board is electrically connected to the conductive layer on the substrate for heating resistance.
3. The heating head according to claim 1, wherein the heat dissipation plate is composed of an iron plate material.
4. A method for manufacturing a heating head, the heating head is composed by fixing a heating resistance substrate of an integrated circuit (IC) comprising a plurality of heating resistors and a heating resistance for each heating resistance on an insulated substrate and a flexible circuit board connected to the heating resistance substrate for supplying power to the integrated circuit (IC) to a heat dissipation board, The method comprises steps comprising a fixed surface of the fixed heating resistance substrate of the heat sink plate and a fixed surface of the fixed flexible circuit board of the heat dissipation plate simultaneously forming a bonding layer; Use this adhesive layer to fix the heating resistance to the heat dissipation plate with a substrate; By bending the flexible circuit board and utilizing this bonding layer, the flexible circuit board is fixed to the heat sink plate.
5. The method of manufacturing a heating head according to claim 4, wherein the adhesive layer comprises an adhesive, and the bonding layer is formed using a screen printing device.
Full text summary
Provides a very inexpensive heating head and its manufacturing method, in which a double-sided tape can be easily applied to the heat sink plate or adhesive can be applied to the heat sink plate without the need for a flexible circuit board or heat sink board that increases the cost. The two sides of the substrate and the flexible circuit board used to fix the heating resistor on the heat sink plate form a flush surface, and the flexible circuit board is fixed to the heat sink board by bending the substrate.
