JP3365548B2 - Thermal head - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal head.

[0002]

2. Description of the Related Art As an example of a conventional thermal head, as shown in a side view of FIG.
For example, a head substrate 3 on which a heating resistor 2, a common electrode, individual electrodes (not shown), etc. are formed on a support plate 1 made of metal such as aluminum, and a connector 4 as a connecting means to the outside are attached. The printed circuit board 5 is fixed by adhesion or the like, and further, a driving element (not shown) for driving each dot of the heating resistor 2 is mounted, and an upper portion thereof is sealed with a resin. It consists of a stop 6. And
As shown in the perspective view of the back side of FIG. 4B, a plurality of screw holes 7 are formed in the bottom surface of the support plate 1, and electronic devices such as a printer are screwed through the screw holes 7. Be assembled into.

Next, an example of actually assembling the thermal head into the printer will be described with reference to the side view of FIG. As shown in FIG. 5, the printer base 8 and the thermal head fixing plate 9 are rotatably connected at a fulcrum portion 10, and the thermal head fixing plate 9 is screwed into the screw hole 7 so that the support plate 1 is in contact with the thermal head fixing plate 9. It is fixed by tightening with 11.
Further, a platen roller 12 is arranged so as to contact the heating resistor 2 from above, and a thermal paper 13 is passed between the platen roller 12 and the heating resistor 2 to operate the thermal head to energize the thermal paper. The color is printed and printing is performed. Here, it is necessary to press the platen roller 12 against the heating resistor 3 with a predetermined pressing force, and the thermal head fixing plate 9
A pressure spring 14 such as a coil spring or a leaf spring is provided between the printer base 8 and the printer base 8, and the heating resistor 2 is pressed against the platen roller 12 with the fulcrum portion 10 as a fulcrum.

[0004]

As described above, when the thermal head is assembled to the printer base, the screw 1
1 requires a certain length or more, and the thickness of the support plate 1 is
In consideration of the length of the screw 11, the screw 11 has a predetermined thickness or more.
Generally, the support plate 1 has a thickness of 3 mm or more and a standard thickness of about 5 mm. This is because, when the thickness of the support plate 1 is thin, for example, 1 mm, the screw 11 penetrates the support plate 1 and the tip of the penetrated screw fixes the head substrate 3 or the circuit board 5 on the support plate 1. Is damaged by pushing up.

If the screw 11 having a length of 1 mm or less is used, for example, in the case of the M3 screw, the thread pitch is 0.5 mm, and the taper portion having no thread at the tip of the screw is used. Therefore, the supporting plate having a thickness of 1 mm is applied only about one mountain, and a sufficient tightening force cannot be secured.
For this reason, it is unavoidable to use a screw longer than the support plate.

In view of the above problems, the present invention provides a thermal head that can be assembled to a printer or the like without reducing the screw length even if the support plate is thin.

[0007]

A thermal head according to the present invention comprises a flat support plate having a thermal substrate fixed to one surface thereof, and a flat surface bent from one side of the support plate to the other surface of the support plate. A support plate and a support plate which are formed at intervals and have screw holes for assembling. As another structure, a flat support plate having a thermal substrate fixed to one surface thereof and a part of the other surface of the support plate are formed so as to extend from at least one side of the support plate. And a support plate assembly piece having an assembly screw hole. And the support plate
Attach the mounting plate or the supporting plate mounting piece to the thermal head fixing plate.
Assemble and fix.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIG. Here, FIG. 1A is a side view, and FIG. 1B is a rear perspective view of FIG. 1A. Further, the same components as those of the conventional example will be described with the same reference numerals. As shown in FIG. 1, a circuit board 5 on which a head substrate 3 on which a heating resistor 2 is formed and a connector 4 for electrically connecting the outside is attached is a flat support plate (hereinafter, referred to as a support plate).
Say. ) 15 is fixed by adhesion or the like. A drive element (not shown) for energizing the heating resistor 2 is mounted on the head substrate 3 or the circuit board 5, and the vicinity including the drive element is sealed with a resin 6. In the following description, substrates such as the head substrate 3 and the circuit substrate 5 fixed on the support plate 15 are collectively referred to as a thermal substrate.

The support plate 15 is provided with a support plate assembly plate 15a for assembling to the printer mechanism via a bent portion 15b formed by bending from one side of the support plate 15. Then, the support plate assembly plate 15a is
It is formed parallel to the surface of the support plate 15. The support plate mounting plate 15a is provided with screw holes 16 at two positions, for example, for mounting to an electronic device requiring a thermal head as described later. Here, the support plate 15
Etc. can be made of aluminum that is easily bent, a metal material such as iron, or a resin that is easily molded.

Hereinafter, an example of assembling the thermal head having the support plate 15 having the above-described structure to the printer will be described with reference to FIG. As shown in FIG. 2, the printer base 8 and the thermal head fixing plate 9 are rotatably connected and attached at a fulcrum 10. Then, the support plate assembling plate 15a is aligned with the thermal head fixing plate 9 and assembled and fixed with the screw 17.

Further, a platen roller 12 is attached to the heating resistor 2 (FIG. 1) so as to come into contact with the heating resistor 2 from above, and a thermal paper 13 is passed between the platen roller 12 and the heating resistor 2 to operate the thermal head. By energizing, the thermal paper 13 develops color and printing can be performed. Here, it is necessary to press the platen roller 12 against the heating resistor 2 with a predetermined pressure, and a pressure spring 14 such as a coil spring or a leaf spring is provided between the printer base 8 and the thermal head fixing plate 9. As a result, the pressure spring 1 with the fulcrum 10 as a fulcrum.
The heating resistor 2 is pressed against the platen roller 12 according to the force of 4.

Here, even if the plates constituting the support plate 15 are thin (approximately 1 mm), there is a gap 18 between the support plate 15 and the support plate assembly plate 15a, so that the support plate assembly plate is formed. 1
Even if the screw 17 longer than the plate thickness of 5a is used, the tip of the screw penetrates the support plate assembly plate 15a and reaches the gap 18,
A thread is applied depending on the thickness of the plate, and a sufficient tightening force can be secured. Even if a long screw is used, the gap 1
By setting the interval of 8 at the time of processing, it is possible to prevent the tip of the screw from reaching the head substrate 3 and the circuit substrate 5, which form the thermal substrate, and there is no risk of damaging these.

Furthermore, since the thickness of the plates constituting the support plate can be reduced, the total thickness from the support plate 15 to the support plate assembly plate 15a via the bent portion 15b and the support plate thickness of the conventional thermal head are the same. In this case, the present invention significantly reduces the weight, which leads to the weight reduction of the thermal head and the cost reduction.
Further, since the gap 18 is hollow, the efficiency of heat radiation to the outside can be improved, and a thermal head without print tailing due to heat storage and print density unevenness can be obtained.

Next, another embodiment will be described with reference to FIG. Here, FIG. 3A is a cross-sectional view and FIG.
Shows a rear perspective view of FIG. In this embodiment, the support plate 19 to which the thermal substrates such as the head substrate 3 and the circuit board 5 are fixed is provided with a pair of support plate assembling pieces 19a, 19a extending inward from two sides of the support plate 19. There is. These support plate assembling pieces 19a have screw holes 20 respectively.
Is formed, and a gap 21 is formed between the support plate 19 and the support plate 19 so that the screw tip can project. Also in this embodiment, as in the first embodiment, the thermal head fixing plate 9 is screwed and incorporated through the screw hole 20.

In addition to the above-described embodiment, the same effect can be obtained by partially bending the support plate integrally with the support plate and forming the support plate assembling means with a certain distance from the support plate.
Further, the support plate assembling means may have a parallel or non-parallel shape, that is, an inclined shape in accordance with the shape of the support plate.
Further, instead of the structure in which the thermal substrate separated into the head substrate and the circuit substrate having the external connection means is fixed on the support plate as in the above-described embodiment, the circuit substrate is omitted and the head substrate is omitted. A thermal substrate provided with a heating resistor, a drive circuit, and an external connection unit may be fixed on a support plate for implementation. In each of the above embodiments, since the thickness of the support plate can be reduced, when forming the bent portion on the support plate,
There is an advantage that it becomes easy to perform bending processing by a press or continuous extrusion molding.

[0016]

According to the thermal head of the present invention, even if the supporting plate to which the thermal substrate is fixed is thin, there is a gap between the supporting plate and the supporting plate assembling means, so that the thermal head is incorporated in a printer or the like. At this time, even if a screw longer than the thickness of the support plate is used, the tip of the screw penetrates the support plate assembly plate, so that a screw thread is applied in accordance with the thickness and a sufficient tightening force can be secured. Further, even if a long screw is used, the tip of the screw does not reach the thermal board, so that they are not damaged.

[Brief description of drawings]

FIG. 1 is a sectional view and a perspective view of a first embodiment of the present invention.

FIG. 2 is a sectional view of the thermal head of the present invention incorporated in a printer.

FIG. 3 is a sectional view and a perspective view of a second embodiment of the present invention.

FIG. 4 is a sectional view and a perspective view of a conventional thermal head.

FIG. 5 is a sectional view of a conventional thermal head incorporated in a printer.

[Explanation of symbols]

15, 19 Support plate 15a Support plate assembly plate 19
a .. Support plate assembly piece

Claims (2)

(57) [Claims] 1. A flat support plate having a thermal substrate fixed to one surface thereof, and a mounting screw formed by bending from one side of the support plate and spaced apart from the other surface of the support plate. A thermal head comprising: a support plate assembly plate having a hole; and a thermal head fixing plate to which the support plate assembly plate is assembled . 2. A flat support plate having a thermal substrate fixed on one surface thereof, and a flat support plate extending from at least one side of the support plate at a distance from a part of the other surface of the support plate. A thermal head comprising: a support plate assembly piece having an attachment screw hole; and a thermal head fixing plate to which the support plate assembly piece is assembled .