JPH07263051A - Connecting structure for printing board - Google Patents

Abstract

PURPOSE:To increase electric current capacity without increasing the number of external connecting terminals of a printing board by branching off at least one among plural terminal pins of a connecting terminal part to be connected to an external control circuit from a midway part. CONSTITUTION:In a printing board 1 of a thermal head, golden circuit patterns 3 to electrically connect a heating resistor R, connecting terminals 4 and a driving element 7 to drive the resistor R to each other, are formed on a surface of an insulating board 2 such as ceramics. A connector composed of plural terminal pins 6 to be sandwiched by and electrically connected to the terminals 4 and housings 5 to integrally hold the pins 6, is installed. When at least one among the pins 6 is branched off from a midway part, plural wiring cables can be connected to these pins. Thereby, electric current capacity to be supplied to a circuit pattern of the board 1 can be increased without changing a diameter of cables.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing substrate such as a thermal head or an LED head used in a printing device such as a facsimile, and more particularly to a connection structure of a connecting terminal portion of the printing substrate.

[0002]

2. Description of the Related Art A conventional printing substrate, for example, a connection structure for a printing substrate of a thermal head is disclosed in Japanese Utility Model Publication No. 2-95642.
As disclosed in Japanese Utility Model Publication No. 2-95643,
Each dot of the heating resistor provided on the ceramic substrate,
A plurality of connection terminals for connecting a driving element for driving the heating resistor with a circuit pattern and for connecting an external control circuit of an electronic device in which the printing substrate is used are provided at one side edge portion of the printing substrate. The connection terminal portion and the driving element are connected by a circuit pattern, and a connector including a plurality of clip terminals is directly connected to the connection terminal portion by soldering or the like.

Then, a wiring cable is connected to each clip terminal, and a signal such as a power source or print data is supplied from an electronic device to which a printed circuit board is attached for use.

[0004]

However, in the conventional connecting structure of the printing substrate, the terminal pins connected to each of the connecting terminals formed on the printing substrate correspond to each other in a one-to-one correspondence. If the printed circuit board has a large current capacity and is used for high-speed printing, the circuit pattern formed on the surface of the printed circuit board can handle the current capacity. However, the current capacity of the terminal pin and the wiring cable from the electronic device connected thereto is exceeded, and the current capacity of the printing substrate is limited by the current capacity of the connection terminal and the wiring cable connected thereto.

Therefore, in order to increase the current capacity of the wiring cable, there is a problem in that the diameter of a part of the wiring cable must be made larger than that of the other wires. Furthermore, if the printed circuit board is made to cope with a large current capacity without changing the wiring cable, it is necessary to increase the number of connection terminals formed on the printed circuit board, which reduces the density of the circuit pattern formed on the printed circuit board. There is a problem that not only the height becomes higher, but also the outer dimension of the insulating substrate becomes larger, which leads to deterioration of the connectivity of the printing substrate.

An object of the present invention is to provide a connecting structure for a printing substrate which can increase the current capacity of the printing substrate without increasing the number of external connection terminals of the printing substrate.

[0007]

In order to solve the conventional problems, the invention described in claim 1 of the present application is a connection structure of a printing substrate, wherein a printing medium on an insulating substrate, and the printing medium. In a connection structure of a printing substrate having a plurality of drive elements for driving a plurality of drive elements and a connection terminal portion connected to an external control circuit and connecting these via a circuit pattern, a plurality of terminals provided in the connection terminal portion At least one terminal pin among the pins is branched from the middle part.

On the other hand, the invention described in claim 2 of the present application is
It is characterized in that the terminal pin branched from the intermediate portion is at least at an end portion of the connection terminal portion. still,
The print medium shown here indicates a resistor for printing by heat energy, a light emitting element for printing by light energy, and the like.

[0009]

As described above, by branching at least one of the terminal pins attached to the connection terminal portion of the printing substrate from the middle portion, it is possible to connect a plurality of wiring cables to the terminal pins. It is possible to increase the current capacity that can be supplied to the circuit pattern of the printed board without changing the diameter of the wiring cable.

Further, the current capacity can be increased without increasing the number of connection terminals on the printing substrate side.

[0011]

Therefore, according to the present invention, the number of connecting terminals on the printed board is not increased in order to increase the current capacity that can be supplied to the circuit pattern of the printed board. The size and weight of the printing board can be reduced without changing the dimensions, and it is not necessary to change the external dimensions of the insulating board used for the printing board, and the insulating board can be unified. Has the effect that can be achieved.

Further, since the number of connecting terminals is not increased on the printed board, it is not necessary to change the mask for printing when forming a circuit pattern or the like on the insulating substrate, and the circuit pattern is not necessary. This has the effect of simplifying the design. Furthermore, when a connector or the like is attached to the insulating substrate to form a printing substrate, it is possible to increase the current capacity without changing the outer dimensions and improve the connectivity of the printing substrate to electronic devices. Has the effect.

Moreover, when the terminal pin having the branch portion is used as the terminal terminal of the connection terminals of the insulating substrate, the number of connectable terminals can be increased without changing the pitch of the connected pins. Has the effect that it becomes possible.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a thermal head according to an embodiment of the present invention. A printing substrate 1 includes a heating resistor R, a connection terminal 4, and an insulating substrate 2 on a surface of an insulating substrate 2 made of ceramic or the like.
A plurality of drive patterns that are electrically connected to a driving element 7 that drives the heating resistor R mounted on the surface of the substrate, and that are sandwiched by connection terminals 4 and electrically connected. The connector including the terminal pin 6 and the housing 5 that integrally holds the terminal pin 6 is attached. In this embodiment, the insulating substrate 2 has the connection terminal portions formed of the connection terminals 4 formed at both ends of one side edge, but the circuit of the printing substrate 1 may be changed depending on the electronic device in which the printing substrate 1 is used. Since the pattern 3 is changed, only one connecting terminal portion may be provided on one side edge of the insulating substrate 2 depending on the size and electric characteristics of the printing substrate 1.

2 (A) and 2 (B) are respectively shown in FIG.
In the drawings showing the terminal pins 6a and 6b used for the connector in the above embodiment, a holding portion B for holding the ceramic substrate 2, a connecting portion A1 connected to an external connecting terminal, and a branch portion A2. There is. In this embodiment, the connection part A1 and the branch part A2 are branched into two, but the number of branches is not particularly limited to two because of the relationship between the current capacity required for the printing substrate and the connection terminal. Absent.

The branching portion A2 may be branched from the connecting portion A1 near the sandwiching portion B or near the end portion of the connecting portion A1. The branching may be made depending on whether the housing 5 is used for the connector or not. You can do it. Further, when the holding portion B is connected to the insulating substrate as in this embodiment and then held by only the elastic force of the holding portion B, connection of the terminal pins to the insulating substrate is simplified in the manufacturing process of the printing substrate. However, in order to enhance the connection strength of the terminal pins, soldering may be performed after the terminals are clamped by the clamping section B, or only soldering may be performed.

After the connection, a resin or the like may be applied to the connecting portion to form a protective layer for insulation. FIG. 3 is a plan view showing a connector of another embodiment, which comprises a housing 5 holding terminal pins 6 integrally, and the connector shown in this embodiment has the terminal pins 6a shown in FIG. Is used at the right end, but in this connector, the location where the terminal pin 6 having the branched connection is used is not particularly limited to the right end, and may be set according to the arrangement of the connection terminals of the printing substrate. Like the one using the terminal pin 6b shown in FIG. 2B at the left end of the connector or the thermal head shown in FIG.
It is also possible to use the terminal pins 6a and 6b on both the left and right ends of the connector.

The size X of the terminal pin 6 on the side of the insulating substrate is the same as that of the conventional printing substrate, and the current capacity that can be supplied to the printing substrate is increasing. Accordingly, the connector is connected to the external control circuit. Dimension Y on the side to be closed is 1
In particular, when the connector using the terminal pin 6a at the right end and the connector using the terminal pin 6b at the left end are used for the printed board, the pins on the side of connection with the external control circuit of the connector are increased. As the number increases, the external dimensions of the connector also increase to the side where the terminal pins 6a and 6b are used.
The connector does not stick out from both ends of the printing board,
Since the external dimensions of the printing substrate do not change from those of the conventional one, it is possible to mount the electronic device in which the printing substrate is used without changing the external dimensions.

Further, in particular, in the case where a terminal pin having a branch portion is used as a ground terminal or a common terminal which generally requires a high current capacity in the circuit pattern of the printing board, the outer dimensions of the printing board should be changed. Therefore, the current capacity that can be supplied is increased, and it becomes possible to mount a printing substrate that can handle high-speed, high-quality printing in electronic devices. FIG. 4 is FIG.
2A, the terminal pin 6a shown in FIG. 2A is used at the right end of the terminal pin 6 in the drawing seen from the direction of the arrow C, that is, from the side inserted into the insulating substrate.

FIG. 5 is a perspective view of an embodiment showing the connection between the connection terminal on one side of the thermal head and the external control circuit. The housing 5 in which the terminal pins 6 are integrally held on the insulating substrate 2 of the printing substrate 1 is shown. , And external connection terminals 8 integrally holding a plurality of wiring cables 9 from an external control circuit of an electronic device (not shown) are inserted into the connector for connection. In this embodiment, the connector having the housing 5 is used, but the connection between the printing substrate and the external control circuit of the electronic device is such that the connector is directly inserted into the terminal pin 6 without the housing 5. Alternatively, the terminal pin 6 without the housing 5 and the wiring cable 9 may be directly connected by soldering or the like.

The connection structure of the present invention is not particularly limited to the thermal head described in the embodiment, and the same operational effect can be obtained even if it is adopted in another printing substrate such as an LED head.

[Brief description of drawings]

FIG. 1 is a plan view showing a printing substrate according to an embodiment of the present invention.

FIG. 2A is a perspective view showing terminal pins used in the printing substrate of the present invention. FIG. 2B is a perspective view showing terminal pins used in the printing substrate of the present invention.

FIG. 3 is a plan view showing a connector of another embodiment used for a printed board.

FIG. 4 is a front view of the connector of another embodiment of FIG. 3 as seen from an arrow C.

FIG. 5 is a perspective view illustrating the connection between the printing substrate and the external connection terminal according to the embodiment of the invention.

[Explanation of symbols]

 1 ...- Printing substrate 2 ... Insulating substrate 3 ... Circuit pattern 4 ... Connection terminal 5 ... Housing 6 ... Terminal pin 7 ... Driving element 8 .... External connection terminals 9 ...- Wiring cables

Claims (2)

[Claims] 1. A printing medium comprising a print medium on an insulating substrate, a plurality of drive elements for driving the print medium, and a connection terminal portion connected to an external control circuit, which are connected through a circuit pattern. In the board connection structure, at least one terminal pin of the plurality of terminal pins provided in the connection terminal portion is branched from an intermediate part, and the connection structure of the printing board. 2. The connection structure for a printing substrate according to claim 1, wherein the terminal pin branched from the middle portion is at least at an end portion of the connection terminal portion.