JPH0578549U - Thermal head - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the size of the thermal head and reduce the number of components. [Structure] Of the end faces 1a and 1b and the flat faces 1c and 1d of the ceramic substrate 1 on which the underglaze 2 is formed,
The individual electrode 3, the common electrode 4 and the heating resistor 5 are formed on the end face 1a side. The individual electrode 3 and the common electrode 4 are routed to the plane 1c side, and the driving IC 6 is mounted on the plane side.
The input electrode 7 and the common electrode 4 of this driving IC 6 are routed to the plane 1d side via the end face 1b side, and the plane 1d
Cross wiring part 8 by forming a multilayer film of an electrode layer and an insulating layer on the side
And the external circuit connection terminal 9 is provided. An overglaze 10 is formed to cover the entire end face including the individual electrode 3, the common electrode 4, and the heating resistor 5. [Structure] Since the number of structural components forming the thermal head can be one component including only the ceramic substrate, it is possible to reduce the size and the number of components.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a thermal head, and more particularly to an end surface type thermal head in which a heat generating resistance is arranged on an end surface of a substrate.

[0002]

[Prior Art]

 Conventionally, as this type of line thermal head, a ceramic substrate with electrodes formed on the surface by a method such as thick film or thin film and a printed wiring substrate for cross wiring were fixed on an aluminum base, and either one was fixed. It is known that a driver IC is mounted on the board of the above or using the TAB method, the both boards are connected by some means, and the printed wiring board is connected to an external circuit by a connector or the like. There is.

[0003]

[Problems to be solved by the device]

 The thermal head having the above-mentioned configuration has three limitations, namely, an aluminum base, a ceramic substrate, and a printed wiring board as head components, and thus there is a limit to miniaturization.

[0004]

[The purpose of the device]

 The present invention mainly aims to provide a thermal head which can be remarkably miniaturized as compared with a conventional thermal head and can reduce the number of constituent parts.

[0005]

[Means for Solving the Problems]

 The present invention forms a plurality of stripe-shaped individual electrodes and a comb-teeth-shaped common electrode that is offset by a half pitch between the individual electrodes on the end surface of an electrically insulating flat plate on which a heat resistance layer is formed. A thermal head having a heating resistor formed so as to cross the individual electrode and a common electrode, and a wear resistant layer formed on the heating resistor and a part or the whole of the individual electrode and the common electrode. , The common electrode and the individual electrode are laid out on a main plane that is in contact with the end face, the driving IC is surface-mounted on the main plane, and the input electrode and the common electrode for the driving IC are the second end face facing the end face. Through a second main plane that faces the main plane, and a cross wiring portion is formed on the second main plane by forming a multilayer film of an electrode layer and an insulating layer. And summarized in that a means for connecting directly to Rigaibu circuit.

[0006]

[Action]

 According to the above configuration, the conventional three components are reduced to one component including only the ceramic substrate, so that the thermal head can be miniaturized. Further, since only one head material is used, it is possible to prevent the generation of stress between the head constituent materials due to the difference in thermal expansion coefficient, which has been a problem in the past.

[0007]

【Example】

 1 and 2 show an embodiment of the present invention. In the figure, reference numeral 1 is an electrically insulating flat plate which serves as a base of the thermal head, and a ceramic substrate is used. An underglaze 2 serving as a heat resistance layer is formed on the entire surface of the opposing end faces 1a 1 and 1b and the opposing flat faces 1c 1d forming the ceramic substrate 1, and a plurality of stripes are formed on the underglaze 2 on the end face 1a side. The individual electrodes 3 and the common electrode 4 in the shape of a comb tooth which is deviated from the individual electrodes by a half pitch, and the heating resistor 5 crossing both electrodes are formed. Further, the common electrode 4 and the individual electrode 3 are formed on the end face 1a. It is routed to the contacting plane 1c side. The driving IC 6 is mounted on the plane 1c side, and the input electrode 7 and the common electrode 4 for the driving IC 6 are routed to the plane 1d facing the plane 1c via the end face 1b facing the end face 1a. There is. On the underglaze on the plane 1d side, a cross wiring portion 8 is formed by forming a multilayer film of an electrode layer and an insulating layer, and this cross wiring portion is directly connected to the external circuit connection terminal 9 provided on the plane 1d side. To be done. Reference numeral 10 is an overglaze serving as a wear-resistant layer that covers the individual electrodes, the common electrode, the heating resistors, and the routing electrodes, and 11 is a sealing resin for the driving IC 6.

The common electrode 4 may be routed directly from the end face 1a side to the end face 1d side. Further, the individual electrode 3 and the common electrode 4 may be routed to the end surface 1d via the end surface 1b or the other end surface.

[0009]

[Effect of the device]

 As is clear from the above description, according to the present invention, the following effects can be obtained. (1) The number of structural parts constituting the thermal head can be reduced from the conventional three parts to one part having only the ceramic substrate, and the size can be reduced as compared with the conventional thermal head. (2) Similarly, since the number of parts is reduced, the material cost can be reduced and an inexpensive thermal head can be provided. (3) Since only one head material (ceramic only) is used, it is possible to prevent stress from occurring between the head constituent materials due to the difference in thermal expansion coefficient, which has been a problem in the past. A head can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a thermal head showing an embodiment of the present invention.

FIG. 2 is a perspective view of a thermal head with a part thereof removed.

[Explanation of symbols]

 1 Ceramic Substrate 1a, 1b End Face 1c, 1d Plane 2 Underglaze 3 Individual Electrode 4 Common Electrode 5 Heating Resistor 6 Driving IC 7 Input Electrode 8 Cross Wiring 9 External Circuit Connection Terminal 10 Overglaze 11 Sealing Resin

Claims (3)

[Scope of utility model registration request] 1. A plurality of stripe-shaped individual electrodes and a comb-teeth-shaped common electrode deviated from the individual electrodes by a half pitch are formed on the end face of an electrically insulating flat plate on which a thermal resistance layer is formed. A thermal head having a heating resistor formed so as to cross the individual electrode and the common electrode, and a wear resistant layer formed on the heating resistor and a part or the whole of the individual electrode and the common electrode. In the above, the common electrode and the individual electrode are laid out on a main plane in contact with the end surface, the driving IC is surface-mounted on the main plane, and the input electrode and the common electrode for the driving IC are opposed to the second end surface. The wiring is routed through the end face to a second main plane facing the main plane, and a cross wiring portion is formed by forming a multilayer film of an electrode layer and an insulating layer on the second main plane, the second main plane Than A thermal head having means for directly connecting to an external circuit. 2. The thermal head according to claim 1, wherein the common electrode is drawn from the first end face directly to the second main plane. 3. The individual electrode and the common electrode are connected to the second electrode.
The thermal head according to claim 1, wherein the thermal head is routed to the second main plane via an end face of or other end face.