JPS6011557Y2 - Connection device for thermal recording head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a thermal recording head connection device for electrically connecting a thermal recording head used in a facsimile or printer to an external circuit.

A thermal recording head (hereinafter referred to as a "maru head") for thermally recording on thermal recording paper such as a facsimile machine generally has a shape as shown in FIG.

In FIG. 1, 1 is a substrate, 2 is a heating resistor, 3 is a common conductor in which a predetermined number of heating resistors 2 are grouped together, and 4 is an individual conductor drawn out from each heating resistor 2.

Therefore, in order to connect the thermal head as described above to an external circuit, the conventional methods shown in FIGS. 2a, b, and c have been used.

Figures 2a, b, and c show the case where the common conductor 3 of the thermal head is connected to an external circuit.

In other words, in Figure 2a, the lead wire 11 is directly soldered to the common conductor 3;
swells up and the soldering is done on part 12 and platen 13.
and the recording paper 14 so as not to interfere with each other.
The platen 13 must be placed near the center of the thermal head so as not to interfere when moving the platen 13 during bonding.

In other words, the heating resistor 2 must be placed near the center of the substrate 1.

Therefore, even if the heating resistor 2 prints on the recording paper 14, there is a drawback that a considerable distance is required before it can be seen.

In addition, Fig. 2 shows a flexible cable 17 that is pressed onto the thermal head substrate 1 using screws 18 using an upper metal fitting 15 and a lower metal fitting 16, but this also has the same drawback as shown in Fig. 2a. was.

In addition, in Fig. 2C, a thin copper plate 19 is directly soldered to the common conductor 3, and the other end of the copper plate 19 is soldered to the lead wire 11; The heating resistor 2 can be provided near the upper end of the substrate 1 as shown in the figure without the drawbacks caused by the one shown in FIG.
If it is turned over for some reason, there is a risk that it will come into contact with the recording paper 14 and damage the recording paper 14, and there is also a risk that the entire copper plate 19 will be peeled off from the turned over part.

As mentioned above, all conventional methods have some drawbacks.
There was room for improvement.

This idea was made in view of the above points. 1. The conductor of the thermal head and the external circuit can be easily and reliably connected, and has high mechanical strength, and there is no risk of damaging the recording paper. An object of the present invention is to provide a connection device for a thermal recording head.

An embodiment of this invention will be described below with reference to the drawings.

In FIG. 3, numeral 21 denotes a thermal head, which, like the thermal head shown in FIG. 1, includes a substrate 1, a heating resistor formed on the surface of the substrate 1 (not shown here), It is composed of common conductors, individual conductors, etc.

22 is a support plate for supporting the thermal head 21 from the back side; 23 is a flexible cable whose one end is connected to the common conductor of the thermal head 21; and 24 is a flexible cable that connects the upper end surfaces of the thermal head 21 and the support plate 22 to each other. Via 23.

The connecting fitting 25 has a U-shaped cross section in order to hold the flexible cable 23 and the common conductor of the thermal head together. This is a pressure welding screw for connection.

FIG. 4 is a cross-sectional view taken along the line A--A in FIG. 3, and further explanation will be given with reference to FIG.

The support plate 22 is provided with a hole 26 into which the tip of the pressure welding screw 25 is inserted in order to position the connection fitting 24, and a hole 27 through which the pressure welding screw 25 passes is provided at a predetermined position of the flexible cable 23. ing.

This hole 27 is located at the end connecting portion 2 of the flexible cable 23.
3a in contact with the common conductor of the thermal head 21, and when folded back at the upper corner of the thermal head 21 as shown in the figure, and further folded back at the upper corner of the support plate 22, the hole 26 provided in the support plate 22 is opened. It is installed in a position facing the .

The tip of the pressure contact portion 24a of the connection fitting 24 and the tip 23a of the connection portion of the flexible cable 23 are set to be substantially aligned.

Needless to say, this flexible cable 23 is coated with an insulator except for the above connection portion, and the rear end portion thereof is connected to an external circuit directly or via a lead wire.

Since the configuration is as described above, the flexible cable 23
Contact the end connecting part 23a of the thermal head 21 with the common conductor of the thermal head 21, position the connecting fitting 24 with the pressure welding screw 25 as shown in FIG. 24a, the end connecting portion 23a of the flexible cable 23, and the common conductor of the thermal head 21 are pressed together, and the flexible cable 23 is reliably connected.

Further, FIG. 5 is for explaining another embodiment of this invention, and in FIG. 5, the same parts as in FIG. 4 are given the same reference numerals.

In the case of FIG. 5, a thin conductive plate 31 is used instead of the flexible cable 23, and this conductive plate 31 is bonded to the connecting fitting 24 via an insulating plate 32.
5 to the thermal head 21, and then attach the thermal head 2.
1 common conductor and the conductive plate 31 are crimped together.

Even in this manner, the same effect as the embodiment shown in FIG. 4 can be obtained.

In each of the above embodiments, connection of a thermal head with a common conductor has been described, but the present invention can also be applied to connection of individual conductors.

As described above, according to this invention, the connecting part on the thermal head can be made extremely compact, and sufficient mechanical strength can be ensured, so the platen can be placed close to the end of the thermal head, which makes it easier to design the equipment. It is extremely advantageous,
Furthermore, the connection work becomes extremely easy.

In addition to the above, since the thermal head is pressed against the support plate, the flatness of the thermal head can also be improved.

Furthermore, according to the present invention, the connecting piece is constructed by a single part that is bent into a U-shaped cross section, and the screw is screwed into the connecting piece with its tip in contact with the support plate surface. Since the conductive wire for circuit connection is pressure-contacted to the conductive wire formed on the substrate of the thermal recording head, only one connecting piece and screw are required as the connecting parts, and the structure can be simplified and inexpensively constructed.

Also, compared to the conventional structure in which a screw is screwed between the upper metal fitting and the lower metal fitting to tighten both metal fittings (Fig. 2b), the amount of protrusion from the side edges of the board and support plate is reduced. This allows the head to be made smaller and more compact.

Furthermore, by reducing the amount of protrusion, more of the printing surface of the recording paper can be exposed, which makes it easier to see the printed results on the recording paper during the printing operation.

Furthermore, in the present invention, a counterbore is provided in the surface of the support plate so that the tip of the screw is held by the counterbore, so that the connection piece can be easily and accurately positioned with respect to the board. Also, it is possible to eliminate misalignment after fixing.

Therefore, the connection work can be performed easily and quickly, and the reliability of the device can be improved.

[Brief explanation of the drawing]

Figure 1 shows the configuration of a general thermal head, Figure 2 shows the configuration of a general thermal head.
Figure a"C is a side sectional view for explaining a conventional connection means, Figure 3 is a perspective view for explaining an embodiment of this invention, and Figure 4 is a sectional view taken along line A-A in Figure 3. , FIG. 5 is a side sectional view for explaining another embodiment of this invention. 1...Substrate, 2...Heating resistor, 3.
...Common conductor, 4...Individual conductor, 21.
...Thermal head, 22... Support plate,
23...Flexible cable, 24...
... Connection fittings, 25 ... Pressure welding screws, 31 ...
...Thin conductor plate.

Claims (1)

[Scope of utility model registration request] A connection device for connecting a conductor formed on a substrate of a thermal recording head and a lead wire for external circuit connection, comprising: a support plate that supports the substrate of the thermal recording head by integrally overlapping it from the back side; and these support plates. and a cross-sectional piece that is loosely fitted into the side end of the substrate of the thermal recording head, holds the external circuit connection conductor by the first piece on the substrate side, and has a screw hole in the second piece on the side of the support plate. The connecting piece is screwed into the threaded hole of the connecting part with the distal end held by the counterbore, and the tightening is performed by the action of the screw hole of the connecting part. and a screw that connects the external circuit connection conductor to a conductor formed on the substrate by means of the first piece by pulling the first piece against the surface of the substrate. Connection device for thermal recording head.