JPH0661943B2 - Thermal head - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an improvement of a thermal head applied to a thermal print recording apparatus such as a printer or a facsimile.

[Technical background of the invention and its problems]

Conventionally, a thermal head is provided with a heating element, which is a plurality of heating resistors, and an electric conductor for supplying electric power to the heating element on a ceramic substrate that has been subjected to glass glaze processing, and is required according to information to be recorded. Recording is performed by passing an electric current through the electric conductor to generate heat so as to generate heat so that a heat pattern can be obtained.

As the ceramic substrate, a polished one is usually used to have flatness. (This is called a flat type) However, the thermal head itself becomes expensive because polishing processing, which requires a high processing cost, is required. Further, in addition to this, a sufficient space is required around the recording medium or an intermediate medium such as a film (for example, a thermal head ink ribbon film) to be inserted between the recording medium and the head. .

[Object of the Invention]

The present invention has been made based on the above circumstances, and an object of the present invention is to achieve a high packaging density with a relatively simple structure, without being restricted by a device used and a structure, and at a low cost. It is intended to provide a good thermal head.

[Outline of Invention]

In order to achieve the above object, the present invention provides a rod-shaped member which is flat along the axial direction and has a curvature in the axial circumferential direction, a heating element arranged on a curved surface on the rod-shaped member, and the rod-shaped member. An extraction electrode for supplying electric power to the heating element, a support for mounting the rod-shaped member, and drive circuit means connected to the drive signal electrode portion of the extraction electrode to drive the heating element, Power supply means connected to an end portion of the drive power supply side electrode located on the opposite side of the drive signal electrode portion of the extraction electrode and extending along the outer periphery of the rod-shaped member, the power supply means and the drive And a substrate for holding the circuit means on the same plane. As a result, the end face type has more space around the head than the conventional flat type, and the structure is easy and inexpensive.

Example of Invention

 Hereinafter, the present invention will be described with reference to the illustrated embodiment.

FIG. 1 is an explanatory view showing the recording principle of a thermal ink jet, in which 1 is a thermal head and 2 is 5-500 μm.
A film as a recording medium made of a metal or an organic material having a large number of small holes (orifus) 2a ...
Is a heating element arranged in the head portion of the thermal head 1,
Reference numeral 4 is a recording ink (hereinafter, simply referred to as ink), 5 is a small hole filled with ink, 6 is an ejected ink droplet, and 7 is a small hole ejected with an ink droplet.

When the film 2 is transferred in the direction of the arrow, the ink 4 is filled in the small holes 2a ... Of the film 2 which have passed through the ink reservoir for accumulating the ink 4. Then, when the small holes 5 filled with the ink 4 reach the thermal head 1 in which the heating elements 3 are arranged, a voltage is selectively applied to the heating elements 3 in accordance with the recording position for rapid heating. . And this heating element 3
The recording is performed by ejecting the ink droplets 6 ... By the pressure of bubbles generated by the heating.

FIG. 2A is a schematic vertical sectional side view showing the recording apparatus of the present invention, in which 8 is a recording sheet as a recording material,
A large number of the recording sheets 8 are accommodated together in a paper feed cassette 49 mounted on the apparatus main body housing 134, and the lower surfaces of these take-out sides are pushed upward by the push-up springs 33 ... Is always in contact with the first feed roller 9. Paper feed cassette 49
When mounted on the apparatus body housing 134, the rubber magnet 47 attached to the tip end thereof is magnetically attracted to the plate 48 provided on the apparatus body housing 134 side and fixed to the apparatus body housing 134. .

The shaft 139 to which the first feed roller 9 is attached is
As shown in FIG.
Paper feed spring clutch 63 and gear 5 that are turned off
It is configured so as to interlock with the paper conveyance motor 54 via 6, 55. Then, the paper feeding solenoid 51 is connected to the apparatus and the processing apparatus 133 for image / data etc.
The paper feed spring clutch 63 is turned on by being excited in response to the recording command (see the drawing), whereby the movement of the paper transport motor 54 is transmitted to the shaft 139 via the gears 55, 56 and the paper feed spring clutch 63. The uppermost recording sheet 8 that is transmitted and is in contact with the first feed roller 9 is fed.

In addition, the paper feed cassette 49 via the first feed roller 9
The recording paper 8 taken out from the recording paper 8 rises along the first paper feed guide 44, and is further fed through the pair of feed rollers 10 and 10 which are in contact with each other and arranged in the transfer direction. It is fed between the guides 44 and 45, and is fed until the tip abuts on the contact portion between the suction conveyance belt 15 of the recording material conveyance mechanism 43 and the registration roller 11 which is in rolling contact with the suction conveyance belt 15, and stands by in this state.

In addition to the paper feeding from the paper feeding cassette 49, this apparatus is also capable of feeding paper from the manual paper feeding base 17, and recording paper such as thick paper collectively set on the manual paper feeding base 17. The second feed roller 19 and the separating roller 18 work to sequentially take out the sheets 8 one by one from the lowermost end, and transfer them to the suction conveyance belt 15 and the same as in the case of the paper feeding from the paper feeding cassette 49. The sheet is fed until the tip comes into contact with the contacting portion with the resist roller 11 which is in contact and is in a stopped state.

The registration roller 11 is adapted to interlock with the paper transport motor 54 (see FIG. 3) via a clutch unit (not shown), and is rotated by an ON operation of the clutch unit. When the rotation of the registration roller 11 starts and stops, the leading edge of the recording paper 8 is the first LED.
It is determined that a certain time has passed since the first photosensor 22 was turned off by blocking the light of 21 and the leading edge of the recording paper 8 abuts the rolling contact portion of the registration roller 11 to cause an appropriate slack. Has been.

By doing so, the tip inclination (skew) of the recording paper 8 is corrected, and the leading end of the recording paper 8 is surely pushed into the rolling contact portion of the registration roller 11, and the registration roller 11 and the suction conveyance belt 15 move the recording paper 8 to the recording paper 8. Secures biting.

A paper dust removing brush 50 that removes paper dust attached to the peripheral surface is slidably contacted with the registration roller 11 to prevent the recording surface of the recording paper 8 from being soiled.

The recording material conveying mechanism 43 includes the first and second rollers 12 and 14 inside the housing 140 and the rollers 12 and 14.
The adsorption / conveyance belt 15 and the air suction duct 30 are installed as a unit to form an adsorption / conveyance mechanism 43a as a first floating portion, and the adsorption / conveyance mechanism 43a as the first floating portion is incorporated. Further, the belt guide plate 27 as the second floating portion is provided, and the belt pressing / retracting means 43 for pressing or retracting the suction conveyance belt 15 toward the recording unit guide 31 side by displacing the belt guide plate 27.
and b.

The belt pressing / retracting means 43b has the following configuration. That is, the belt guide plate 2 as the second floating portion
The air suction duct 30 has one end rotatably supported and the other end which is constantly biased downward by a belt guide plate pressing spring 26. It is pressed against the guide 31.
Further, the attracting member 141 is attached to the back surface of the pressing plate 27 so as to face the electromagnetic coil 28. When the electromagnetic coil 28 is excited, the pressing plate 27 is pressed.
Is displaced against the biasing force of the pressing spring 26.

In addition, the suction conveyance mechanism portion 43a as the first floating portion is elastically elastic by the roller pressing spring 25 hung on the first roller 12, and the belt guide plate 27 as the second floating portion is elastically elastic by the pressing spring 26. When the thick recording paper 8 is supported and supplied, it can be displaced by that amount.

In addition, the impact of the belt guide plate 27 as the second floating portion,
It is adapted to be buffered by the high-viscosity fluid buffer 29.

As described above, the recording material conveyance mechanism 43, which is composed of the suction conveyance mechanism portion 43a and the belt pressing / retracting means 43b and is provided in a floating manner with respect to the heating elements 3, ...
It is configured so as to be rotatable about the axis of (1) and can be rotationally displaced in the direction of arrow A in FIG. 2 so as to open the recording paper conveyance path.

Then, when the registration roller 11 starts to rotate, the leading edge of the recording paper 8 and the suction conveyance mechanism portion 43
The recording paper 8 is caught between the suction conveyance belt 15a of FIG.
Is clamped with an appropriate pressure by the urging force of the roller pressing spring 25. Then, it is conveyed by the sandwiching conveyance force of the registration roller 11 and the first roller 12 and the suction conveyance force of the suction conveyance belt 15.

At this time, the recording sheet 8 is pressed against the recording section guide 31 made of a flexible film having a thickness of 0.2 mm by the action of the belt pressing / retracting means 43b as shown in FIG. It is conveyed while rubbing against 31.

The recording section guide 31 is fixed with the thermal head 1 as a reference, and the sliding surface of the recording section guide 31 is held at a constant interval with the heating elements 3.
The recording surface (lower surface) of the recording paper 8 and the surface of the film 2 that moves while closely adhering to the heating elements 3 arranged in the head portion of the thermal head 1 have a minute gap, for example, 0.
It is configured to be able to move while always maintaining 2 mm.

The leading edge of the recording section guide 31 is set to about 0.7 mm from the heating elements 3 ..., and the gap between the recording surface of the recording sheet 8 and the film 2 is reliably held.

However, in the experiment, the above-mentioned leading edge is changed to the heating elements 3 ...
It was found that up to mm, a constant gap can be obtained because the vicinity of the heating elements 3 ... Is a plane.

In fact, according to the performance test of the example, it was confirmed that the gap between the surface of the film 2 and the recording surface should be between 0.1 and 0.3 mm in order to maintain the resolution of 8 lines / mm. Was done.

Therefore, the recording section guide 31 has a thickness of 0.1 to 0.3 mm.
Of course, it may be a flexible thin plate.

However, since the gap between the recording surface of the recording paper 8 and the film 2 is very small, there is a risk that the ink 4 on the film 2 will contact the recording surface. According to the performance test of this embodiment, the surface of the recording section guide 31 is inspected. Has a water impermeability characteristic, and the edge portion toward the heating elements 3 has a knife edge shape, so that the ink 4 is drawn in by the film 2 on the lower surface of the recording section guide 31 along the moving direction of the film 2. It was observed that the recording surface side was prevented from expanding and leaching.

In this embodiment, the film 2 is photo-etched with a polyimide film having a thickness of 12.5 .mu.m to form a large number of small holes 2a having a diameter of 25 to 30 .mu.m. Treated. As a result, the surface of the film 2 facing the recording paper 8 does not ooze well, and even if the ink 4 adheres to the surface, the surplus ink scraping members 42 and 89 described later are replaced with hydrophilic elastic members. By doing so, it can be completely cleaned. In this way, the recording section guide 3
It is possible to more effectively prevent the ink 4 from overflowing from the edge portion of 1.

Further, the surface of the film 2 facing the thermal head 1 and the surface of the thermal head 1 are subjected to abrasion resistance treatment with a siloxane derivative having a thickness of about 3 μm, and the film 2 moves on the thermal head 1 during recording. However, the film 2 and the thermal head 1 are not worn or scratched.

This siloxane derivative can be produced by, for example, reacting tetratetrafluorosilicon tetrachloride with water in a predetermined amount of a monohydric alcohol or ester to obtain a colloidal dispersion of a partial hydrolyzate.

This solution is applied to one side of the film 2 at 50 ° C to 10 ° C.
A film is formed by leaving it to stand at 0 ° C. for several hours. Experiments have shown that this abrasion resistant film does not get scratched by rubbing with steel wool.

In addition, since the present siloxane processing is a thin film of glass-like substance silica, it is also thermally strong, has some silanol groups in the siloxane network, is hygroscopic, and has hydrophilicity. Adhered uniformly, and the ink 4 can be rapidly supplied to the heating elements 3 through the contact surface with the thermal head 1 by the capillary phenomenon, so that the supply shortage of the ink 4 is completely eliminated.

Further, as will be described later, when the film cartridge 40 including at least the film 2, the excess ink scraping members 41, 90, 42, 89 and the container 77 is attached to and detached from the apparatus, the surface of the film 2 is cleaned cleanly. Because it is done, you can keep your hands clean.

Since the recording sheet 8 is lightly pressed against the film 2 which is in close contact with the heating elements 3 through the recording section guide 31, the recording sheet 8 depends on the thickness of the recording section guide and the film 2.
Since the gap between the recording surface and the heating elements 3 is determined, the desired gap can be maintained accurately.

When the leading edge of the recording paper 8 further advances, the suction conveyance mechanism 43
The sheet is nipped and conveyed by the second roller 14 a and the sheet discharge roller 13. At this time, the recording surface of the recording paper 8 is supported in a dot shape by the needle roller portion 104 of the paper discharge roller 13, and the reference roller portions 105 and 106 are in contact with the suction conveyance belt 15 at both ends. Therefore, the undried recorded image is not disturbed because it is conveyed without being applied with excessive pressure. (See FIG. 7) Further, the recording paper 8 advances, and the trailing end of the recording paper 8 passes through the rolling contact portion between the registration roller 11 and the first roller 12. At this time, the rear end portion of the recording sheet 8 is conveyed while being rubbed against the recording section guide 31 while receiving the full load of the recording material conveying mechanism 43. In other words, the basic conveyance force of the recording paper 8 is only the suction conveyance force of the suction belt 15, and the conveyance is performed while receiving a large frictional force, so that the conveyance is uncertain.

However, in the present embodiment, the force for pressing the recording sheet 8 against the recording section guide 31 is transmitted through the belt pressing / retracting means 43b, and the belt guide plate 27 as the second floating section transfers the recording section to the belt guide plate 27. By the reaction force from the guide 31, it is pushed upward relative to the belt guide plate pressing spring 26, through the high-viscosity fluid shock absorber 29, and to the housing portion of the suction conveyance mechanism portion 43a as the first floating portion.

In this way, after the trailing edge of the recording sheet 8 has passed, the temporarily separated registration rollers 11 and the suction conveyance belt 15 come into rolling contact again, so that the pressure applied to the recording sheet 8 is reduced and the belt guide plate 27 is reduced. The total load and the biasing force of the belt guide plate pressing spring 26 are used to realize the smooth conveyance of the recording paper 8.

Further, the recording sheet 8 advances, and when the trailing edge of the recording sheet 8 passes the edge portion of the recording section guide 38 on the thermal head 1 side, the belt guide plate 27 receives no reaction force from anywhere.
Full load of belt guide plate 27 and belt guide plate pressing spring 26
Will be pushed down by the force of.

Therefore, as soon as the trailing edge of the recording sheet 8 passes through the edge portion of the recording section guide 31, the surface of the film 2 and the recording surface of the recording sheet 8 come into contact with each other, and the trailing edge of the recording sheet 8 is covered with the ink 4. It has the problem of becoming dirty.

However, in this embodiment, this problem is solved by the procedure described below. First, since the belt guide plate 27 as the second floating portion has already been pushed upward through the high-viscosity fluid shock absorber 29 as described above, the trailing edge of the recording paper 8 passes through the edge portion of the recording portion guide 31. Even so, the downward movement is slowly lowered by the buffering effect of the high viscosity fluid buffer 29. Therefore, the recording sheet 8
The trailing edge of the recording sheet 8 can pass through the heating element 3 while the recording surface of the recording sheet 8 approaches the surface of the film 2.

Further, in this embodiment, the front end or the rear end of the recording paper 8 is heated in order to prevent the front end or the rear end of the recording paper 8 from being bent or bent and coming into contact with the surface of the film 2. The electromagnetic coil 28 is excited so as to move away from the surface of the film 2 by ± 6 mm on both sides of the element 3, so that the entire belt guide plate 27 as the second floating portion is attracted upward. .

In this way, the recording paper 8 does not come into contact with the film 2 and is not contaminated, and the recording paper 8 passes through the arrangement portion of the rollers 13 while maintaining a very small gap, and the paper is discharged in a state in which a clear recording is made. 16 will be ejected.

Further, when the sheet is discharged, the trailing edge of the recording sheet 8 is the second LE.
The tip of D23 is blocked, and the rising signal of the second photo sensor 24 is detected to detect that the recording paper 8 is reliably ejected.

Next, referring to FIGS. 2A and 3, the ink is supplied from the ink container 64 to the film cartridge 40 as a recording medium cartridge, and the ink is supplied from the ink supply section of the film cartridge 40 to the film 2. Supply will be described.

The film cartridge 40 and the ink container 64 can be separated. The ink 4 is stored in an ink container 64, and the ink container 64 is a film cartridge 40.
It is screwed into and fixed to the ink container mounting portion 65 of. At this time, the transparent ink supply tube 71 of the ink container 64
Pushes up the valve 68 of the film cartridge 40, which is in close contact with the ink container mounting portion seal 73, against the biasing force of the cartridge valve spring 69.

On the other hand, the valve 68 of the film cartridge 40 pushes the ink container opening / closing bar 70 upward, and thus pushes the valve 67 of the ink container 64 against the valve spring 66, so that the ink 4 in the ink container 64 flows out. . The ink 4 that has flowed out of the ink container 64 flows out until the obliquely cut tip of the transparent ink supply tube 71 is filled, and a small hole formed around the valve 68 of the film cartridge 40 and an ink supply passage. Fine ink supply passages 72, 93 formed at the bottom of the container portion 77 of the film cartridge 40 via 94 (see FIG. 6).
Flow into.

The ink 4 further penetrates into the ink supply members 37 and 39 composed of felt, and the film 2 is passed through the ink supply members 37 and 39.
The ink 4 is applied to the
A is filled with the ink 4, and is used as a recording ink droplet 6 due to bubbles in the ink 4 due to the movement of the film 2 and the rapid heating of the heating elements 3.

In this way, when the ink 4 is consumed and the level of the ink 4 drops from the oblique cut portion at the tip of the transparent ink supply tube 71, air is sucked from the air suction passage 74 provided in the ink supply portion of the film cartridge 40. ,
This air flows into the ink container 64 through the cut portion of the transparent ink supply tube 71, and new ink 4 is caused to flow out.

By the way, the air suction passage 74 is located in the upper portion of the ink supply section, and the air volume in the ink supply section is made as small as possible as can be seen from FIGS. 2 (a) and 3 and will be described later. As described above, the first excess ink scraping members 41, 90 and the second excess ink scraping members 42, 89 made of elastic rubber allow air to flow into and out of the ink supply section through the small holes 2a of the film 2. Since it is possible only when the ink passes through the first and second surplus ink scraping members 41, 90, 42 and 89, the replenishment of the ink 4 from the ink container 64 to the ink supply portion is performed on the film 2. It is possible only when the film cartridge 40 is moved, and is not carried out when the film cartridge 40 is replaced or when the film cartridge 40 is not in operation such as when the film cartridge 40 is moved.

Therefore, the problem that the ink 4 is excessively supplied to the film cartridge 40 and leaks and scatters from the film cartridge 40 can be prevented.

Further, since the ink 4 is supplied to the film 2 through the ink supply members 37 and 79 composed of felts as shown in FIGS. 2 and 3, the free surface as a liquid in the ink supply section. Can be prevented from being formed, and since the ink 4 is trapped between the fibers by the force of the surface tension, it becomes easy to prevent the ink 4 from leaking to the outside of the film cartridge 40.

Next, the operation of detaching the ink container 64 from the ink container mounting portion 65 of the film cartridge 40 will be described.

When the ink 4 in the ink container 64 is consumed and disappears due to the replenishment of the ink 4 described above, the level of the ink 4 further decreases and reaches the transparent ink supply tube 71. At this time, the light of the ink detecting LDE 75 starts to pass and the ink detecting photosensor 76 starts to be turned on. By catching the rising edge of this signal, the state in which there is no ink in the ink container 64 is detected.

Based on the detection signal indicating that the ink is absent, the device is displayed on the display part of the device or on the display part of the processing device 133 such as an image / data connected to the device, as described later. If the ink 4 is present in the ink container 64, there is no ink in the ink container 64, that is, an indication that the replacement of the ink container 64 is supported is displayed.

Although the ink container 64 is replaced in this manner, in the case of the present embodiment, the removal procedure and the valve 6 of the ink container 64 are replaced.
7. The operation of the valve 68 of the film cartridge 40 is completely opposite to that in the case of attachment.

That is, the valve 68 of the film cartridge 40 rises and comes into close contact with the lower surface of the ink container mounting portion seal 73 by the force of the cartridge valve spring 69, and the ink 4 in the film cartridge 40 leaks from the ink container mounting portion 65 to the outside. It is designed to prevent scattering.

By the way, the ink container 64 has a capacity of 100c in this embodiment.
Ink 4 except the ink supply tube 71 described above in c.
It is an opaque container in consideration of the weather resistance of the sheet-like recording paper A4 size of 2000 to 50 at a normal recording density.
The film cartridge 40 can record 100 sheets, while the film cartridge 40 has about 100,000 sheets / A4 for a period of about 3 sheets due to problems such as paper dust and mold in the small holes 2a of the film 2 and clogging due to drying of ink.
It will be necessary to replace it in a year. For this reason, the film cartridge 40 and the ink container 64 are separable, and for that reason, the ink 4 can be easily prevented from leaking or evaporating in each container.

Therefore, the attachment of the film cartridge 40 to the recording device will be described.

In this apparatus, the thermal head 1 is fixed to the main body housing 134, and the film cartridge 40 has a window in the container located at the film exposed portion 86 of the cartridge 40 shown in FIGS. 4 (b) and 5. And the main body housing 134 so that the window surrounds the thermal head 1.
It can be set to.

That is, in FIG. 3, when the film cartridge first support portion 60 is inserted into the hole portion of the main body housing 134 and the film cartridge second support portion 61 provided at the other end is pushed downward, the cartridge fixing spring 62 moves to the right. Then, the head of the fixing spring 62 falls into the concave portion of the film cartridge second supporting portion 61, and the film cartridge 40 is fixed.

As described above, since the container portion of the film cartridge 40 has a window shape, the film cartridge 40 has a structure that has sufficient strength.

Further, since the film cartridge 40 is attached as described above, the film cartridge 40 can be easily attached and detached, and the ink container 64
It can be easily attached and removed even with the attached. That is, the color of the ink 4 can be easily changed. When the film cartridge 40 is attached or detached, the recording member 43 rotates as shown by an arrow A in FIG.
Further, as shown by an arrow B, the recording section guide 31 is rotated, the upper portion of the film cartridge 40 is largely opened, and the paper jam (jam) in the recording section, the paper waste of the film 2 is removed, and the film cartridge 40 is replaced. Etc. can be done easily.

When the film cartridge 40 is removed, in order to prevent the ink 4 remaining in the film cartridge 40 from leaking or evaporating, the film cartridge 40 has a cartridge lid 8 as shown in FIG.
5 and rotates as shown by an arrow D to cover the film exposed portion 86, and the protrusion of the lid 85 causes the first excess ink scraping member 4 of the film cartridge 40.
1, 90, and second surplus ink scraping members 42, 89
And the film cartridge 40 is hermetically sealed.

In addition, the ink absorbing members 34 and 35 shown in FIG.
As described above, when the film cartridge 40 is attached or detached, the surplus ink 4 accumulated on the upper part of the thermal head 1 flows down through the wall surface of the thermal head 1 and is scattered into the apparatus. Ink absorbing members 34 and 35, which are in contact with the thermal head 1, are attached to the lower portion of the thermal head 1 to absorb the ink 4 that is about to flow down and scatter, thereby preventing the above problems.

Now, the operation when the film 2 is driven will be described.

FIG. 4 (a) is a side view of a drive unit of a film moving mechanism as a recording medium moving mechanism, and FIG. 4 (b) is a plan view of the same portion. The film 2 is rotated in the clockwise direction and the counterclockwise direction as viewed from the film drive motor gear 58 as the recording medium drive motor gear of the film drive motor 52 as the recording medium drive motor, as shown in FIG. ), Move upward and downward respectively.
When the film drive motor gear 58 rotates clockwise, the film drive gear 78 rotates clockwise when viewed from the side of FIG. 4 (a).

Drive shaft 8 for moving a film as a drive shaft for moving a recording medium
Since one end of the left-handed spring 84 fitted to the gear 7 is engaged with the concave portion of the gear 78, the clockwise rotation of the gear 78 causes the left-handed spring 84 to be wound in such a manner that the left-hand spring 84 is further attached to the film moving drive shaft 87. And transmits the power of the gear 78 to the film moving drive shaft 87.

At this time, the film drive gear 59 as a recording medium drive gear also rotates clockwise, but relatively drives the right-handed spring 83 fitted to the film moving drive shaft 88 as a recording medium moving drive shaft. It acts in the direction of loosening from the shaft 88. However, in the case of the embodiment, the drive shaft 8
8 and the right-handed spring 83 rotate in the same direction, so that the drive shaft 88 and the right-handed spring 8 are substantially rotated.
A slip with 3 occurs.

By the way, when the film cartridge 40 is attached or detached, the film drive gears 59 and 78 are separately engaged with the motor gear 58, and there is a risk that the film 2 may be loosened or excessively tensioned. ing.
However, with respect to the latter, in the configuration of this embodiment, the drive shaft 88 and the right-handed spring 83 slip and the excessive tension can be relieved.

Further, as shown in the perspective view of the moving mechanism in the embodiment of FIG. 6, the film cartridge 40 is provided with a film tension mechanism 142 as a recording medium tension mechanism on the side opposite to the film moving drive shafts 87 and 88. Therefore, the film 2 is not loosened, and the film 2 can be rubbed against the tip heating element 3 ... Of the thermal head 1 at an appropriate pressure. A pin 101 is provided at one end of the film moving drive shaft 87 by means of a pin 101.
0 is fixed, and one end of the drive shaft 88 is engaged with a torsion spring fixing portion 96 at one end thereof.
5, the other end of the torsion spring 95 engages with the recess 98 of the rudder wheel 97, and the rudder wheel 97 is connected to the rudder wheel 100 via the rudder chain 99.

By the way, when the ladder chain 97 is hung on the ladder wheels 97 and 100, the film winding shaft 36 as a recording medium winding shaft is counterclockwise through the torsion spring 95, and the film winding shaft 36 as a recording medium winding shaft. 38 is a torsion spring 95 which is appropriately twisted in advance so as to urge it clockwise. Therefore, the film 2 can be appropriately tensioned according to the torsional force of the torsion spring 95, that is, the torque.

In this way, when the film cartridge 40 is attached to the apparatus, the problem that the film 2 is loosened is eliminated, and the film 2 always slides in close contact with the tip of the thermal head 1 with an appropriate pressure.

Next, referring to FIG. 4 (a), the drive gear 58 is the gear 5
The case of turning counterclockwise when viewed from the mounting side of 8 will be described.

At this time, the drive gear 59 rotates counterclockwise, and the right-handed spring 83 acts so as to be entangled with the film drive shaft 88. Thus, in this case the film 2 is in the downward direction, and thus in the clockwise direction of the film drive motor 52,
The film 2 can be reciprocated according to the counterclockwise rotation, and the right-handed spring 83 and the left-handed spring 8 can be moved.
4 and the film tension mechanism 142 prevent the film 2 from being loosened when the film cartridge 40 is attached or detached, and prevent excessive tension from damaging the film 2 or the thermal head 1.

At any rate, the film drive motor 52 operates to reciprocate the film 2 to fill the multi-hole portion 92 of the film 2 with the ink 4 in the portions of the heating elements 3 of the thermal head 1 for recording. It is like this.

Further, the film 2 is guided by guide means composed of side guides of the film 2 shown at 102 and 103 in FIG. 6 located at both ends of the thermal head 1 to prevent lateral displacement of the film 2. .

By the way, knowing where the start or end of the multi-hole portion 92 of the film 2 is located, when starting recording, the starting position of the multi-hole portion 92 in the moving direction of the film 2 is located at the heating element 3. When you come to, you need to be able to start recording. In this embodiment, as shown in FIG.
As shown in (b), a film position indexing board 80 as a recording medium position indexing board is attached to the drive shaft of the film drive motor 52, and the starting position of the multi-hole portion 92 of the film 2 is shown on this indexing board 80. The film position detector 7 is provided with a film first position detecting slit 81 as a recording medium first position detecting slit and a film second position detecting slit 82 as a recording medium second position detecting slit.
The position of the film 2 is detected by 9.

When the film drive motor 52 rotates, the film position detector 79 senses the short light pulse and the long light pulse due to the short slit and the long slit of the slit 81, and in response thereto, the constant period built in the electric control circuit 32. Of the slit 81 at the rear end in the clockwise direction of the long slit of the slit 81, when the slit 81 is the slit for detecting the film first position, the single optical pulse of the slit 82 is detected. It is detected by the device 79, and it is determined that this is the slit for detecting the film second position. Thus, the film drive motor 52 detects the film first position detection slit 81 and is stopped.

At this time, the non-hole portion 91 of the film 2 (see FIG. 9) covers the film exposed portion 86 of the film cartridge 40,
The multi-hole portion 92 is housed in the lower ink supply portion of the first and second surplus ink scraping members 89 and 90 of the film cartridge 40. Therefore, since the non-hole portion 91 of the film 2 is sandwiched between the film cartridges 40, the film cartridge 40 is sealed from the outside air.

Therefore, the ink 4 in the film cartridge 40 evaporates and the viscosity of the ink 4 increases, so that the speed at which the ink 4 blows out from the small holes 2a of the film 2 is reduced or the viscosity is high and jetting does not occur, which adversely affects recording. Can be prevented.

By the way, when recording, images and images connected to the actual device
Before receiving a recording command from a processing device (not shown) such as character data and driving the first feed roller 9 to feed the recording paper 8 to the recording portion, the film 2 is kept for a predetermined time, that is, a preset pulse. Number of film drive motors 5
2 is moved by rotating it counterclockwise as indicated by the arrow in FIG. 4 (a) to position the end of the multi-hole portion 92 in the traveling direction at the heating element 3 and wait for the recording sheet 8 to arrive at the end of recording. The film 2 is moved in synchronization with the leading edge of the sheet 8. At this time, the moving speed of the film 2 is 20 mm / sec which is 1/2 of the moving speed of the recording sheet 8 of 40 mm / sec.

Actually, even when the speed of the recording paper 8 is changed within the range of 10 to 100 mm seconds, the relative movement direction of the film 2 and the recording paper 8 is the same direction or the opposite direction at the recording density of the recording paper 8, that is, at the coverage rate of 75%. The moving speed of the film 2 is V regardless of the direction.
If it is / 4 or more, it is almost D1.0 (black solid, coverage rate 75
%) Or more.

The pattern of this experiment is shown in FIG. Therefore, the moving width of the film 2 can be made shorter than the recording length (recording direction) of the recording sheet 8, and therefore, the multi-hole portion 92 of the film 2 is formed.
The area of the film 2 can be reduced, and the film 2 can be easily manufactured. That is, if the area of the large number of holes 92 is large, it is difficult to make the diameter (25 to 30 μm) of the small holes 2a uniform over the entire area. Therefore, the diameter of the small holes 2a becomes small, for example, near the periphery. As a result, the recording density becomes uneven. Since the area can be reduced in this embodiment, such a problem can be prevented.

In this way, the film 2 moves in this way, and the rear ends of the multi-hole portion 92 on the first and second surplus ink scraping members 89, 90 reach the portion of the heating element 3. At this time, the film position detector 79 detects the film second position detecting slit 82. Of course, in order for the positions of the respective parts of the film 2 and the relative positions of the first and second position detecting slits 81 and 82 of the film position indexing disk 80 to have the above-described relationship, At the time of initial setting, the film 2 has the first and second surplus ink scraping members 8
It is necessary for the film drive motor 52 to be wound on the 9th and 90th sides, and in the film drive motor 52, the position of the short slit in the long slit of the film first position detection slit 81 and the short slit pair is detected by the film position detector 79. It is necessary to detect and stop.

In the present embodiment, this is premised.

Now, when the recording paper 8 is continuously fed and the even-numbered recording paper 8 is recorded, the first,
The second surplus ink scraping members 89, 90 are wound until the ends thereof reach the film winding shaft 38, and after the ink 4 is supplied, the film 2 is moved in the direction opposite to the moving direction of the film 2 described above. After waiting for a certain time until the end reaches the heating elements 3, ..., Recording is performed synchronously with the leading end of the recording paper 8.

Further, in the continuous recording, the first and second surplus ink scraping members 4 are used for recording the odd-numbered recording paper 8.
The end of the multi-hole portion 92 on the side of 1, 42 is the film winding shaft 3
6 and the ink 4 is supplied to the heating element 3
... and the film 2 is moved in synchronization with the leading edge of the recording paper 8.

Since the recording is continued by the reciprocal movement of the film 2 as described above, continuous recording is possible even if the film is not an endless film.

Now, next, the first and second surplus ink scraping members 41,
As shown in FIG. 6, the positions of 90 and 42, 89 are arranged such that the contact positions with the film 2 are different from each other.
The surplus ink scraping members 42 and 89 are located above the first surplus ink scraping members 41 and 90. The necessity of having such an arrangement will be described with reference to the first and second surplus ink scraping members 41 and 42.

First, the film 2 must be arranged so that the film winding shafts 36 and 38 reach the apex of the thermal head 1 and come downward, so that the recording portion can be compactly packed and the recording paper 8 can be kept in a tight gap in the heating element 3. It is impossible to bring them closer together for transport. Therefore, if it is located below the first surplus ink scraping members 41 and 90 located on the thermal head 1 side with respect to the film 2, the second
The distance between the excess ink scraping members 42 and 89 can be reduced, and the area of the film exposed portion 86 of the film cartridge 40 of the film 2 can be reduced.

Therefore, the film cartridge 40 can be formed compactly. From the point of view of the effect of scraping excess ink when the film 2 is moved, it is as follows.

First, the case where the film 2 moves in the direction of arrow G in FIG. 6 will be described. The film 2 replenished with the ink 4 by the ink supply member 39 moves upward, and the surplus ink is scraped off from the film 2 by the first surplus ink scraping member 41. However, during recording, the multi-hole portion 92 passes through the surplus ink scraping member 41, so that the excess ink 4 moves through the multi-hole portion 92 to the side opposite to the thermal head 1 by a certain amount.

Further, the ink 4 that has moved to the opposite side is scraped by the second surplus ink scraping member 42, and again moves to the thermal head 1 side. Thus, when the film 2 moves in the G direction and the multi-hole portion 92 of the film 2 passes through the first and second surplus ink scraping members 41 and 42, not only the small holes 2a ... , A sufficient amount of ink 4 is applied / supplied over the entire surface of the film 2.

Therefore, as described above, the film speed can be reduced to 1/4 of the speed of the recording sheet 8 as described above.

Now, let us consider a case where the multi-hole portion 92 moves downward in the portions of the first and second surplus ink scraping members 41 and 42, conversely. In this case, first, the second surplus ink scraping member 42 scrapes the recording side surface of the film 2. Therefore, the excess ink 4 adhering to the surface of the film 2 is scraped off as well as the dust and paper dust adhered to the film 2. In this way, the ink 4 accumulated at the tip of the surplus ink scraping member 42 moves to the thermal head 1 side through the small holes 2a of the multi-hole portion 92 of the film 2, and then the first surplus ink scraping member 4
And the first excess ink scraping member 4
Collect at the tip of 1.

The surplus ink 4 that has been scraped off and collected is again used for the small holes 2 of the above-described multiple hole portion 92 on the side opposite to the thermal head 1.
Move through a ... In this way, the surplus ink 4 at the time of recording is collected in the ink 4 supply portion of the film cartridge 40.

On the other hand, the non-hole portion 91 of the film 2 is directed in the F direction, that is, downward, to the first and second excess ink scraping members 4
The state when passing through 1 and 42 will be described. At this time, the surface of the film 2 opposite to the thermal head 1 has already been cleaned by the second surplus ink scraping member 89, so
It is not necessary to scrape off the ink with the excess ink scraping member 42. However, paper dust and dust accumulate on the tip of the second surplus ink scraping means 42.

On the other hand, since the film surface on the thermal head 1 side is also cleaned in advance by the first excess ink scraping member 90,
The need for ink scraping by the first surplus ink scraping member 41 is almost eliminated.

Thus, the non-hole portion 91 of the film 2 is the film exposed portion 8 as the recording medium exposed portion of the film cartridge 40.
When 6 is covered, the exposed part of the film 2 is cleaned cleanly, and there is no danger of soiling hands when attaching or detaching the film cartridge 40.

Further, since the lengths M and N (see FIG. 9) in the moving direction of the non-hole portion 91 are longer than the film exposure width E (see FIG. 6) of the film cartridge 40 or the like, the first excess ink scraping member 41, 90, second excess ink scraping member 4
Air can be prevented from entering and exiting through the gap between the two and 89. Therefore, the evaporation of the ink 4 can be prevented, and the viscosity of the ink 4 can be prevented from changing, so that the quality of recording and printing can be kept constant.

Next, the operation of removing the paper dust attached to the film 2 will be described.

As described above, when the film 2 is moved in the G direction, the paper dust and the dust accumulated on the tip portion of the second surplus ink scraping member 42 move together with the film 2 while being attached to the film 2, and the thermal head 1 It reaches to the heating element 3 part at the top of. At this time, the film 2 is attached to the thermal head 1
2 is moved back and forth a few times with the heating element 3 in between, and at the same time, the suction fan 53 of FIG.
The paper dust and dust on the film 2 are sucked into the air suction guide 57 through the suction port 107.

In this way, the paper dust and dust attached to the film 2 can be removed, so that the multi-hole portion 92 of the film 2 can be removed.
It is possible to prevent clogging of the small holes 2a with paper dust and dust.

In the present embodiment, the paper dust removing step is carried out after a certain period of time from the end of a series of continuous recording, so that the problem of slowing the recording speed does not occur.

Further, as described above, since the paper dust removing step is performed in the non-hole portion 91 of the film 2, the ink 4 on the film surface has been cleaned, so that the ink 4 and the like are sucked into the air suction guide 57. It is also possible to prevent the problem that the ink 4 adheres to the suction belt 15 or the like.

Here, the operation of the film 2 when a series of recording operations are completed will be described.

After a series of recording operations is completed, the film 2 is moved at a speed slower than the moving speed at the time of recording for a fixed time.
This is done to prevent ink 4 from being depleted from the heating elements 3 ... Of the thermal head 1 before a series of recording operations is completed. After that, the above-mentioned paper dust removing process is continued for a certain period of time, and then the non-hole portion 91 of the film 2 covers the film exposed portion 86 of the film cartridge 40.

By the way, the first surplus ink scraping members 41, 90 are made of elastic members, and the edges of the first surplus ink scraping members 41, 90 facing the thermal head 1 are located on the lower surface of the film 2 and are in close contact with the thermal head 1. The ink 4 flowing down through the wall surface is passed through the small holes 2 of the multi-hole portion 92 of the film 2.
It can be collected in the ink supply section of the film cartridge 40 through a. The first and second surplus ink scraping members 41, 90, and 42, 89 are made of a non-breathable material that prevents the inflow and outflow of air and ink 4 inside and outside the film cartridge 40.

Next, the relationship between the diameter of the small holes 2a of the film 2 and the pitch between the small holes 2a will be described with reference to FIG.

In the figure, an arrow I indicates the moving direction of the film 2, and a line connecting the centers of the small holes 2a is an equilateral triangle whose one side is orthogonal to the arrow I. In the figure, H and V are the geometrical dimensions of the heating element 3, which are 100 μm to 125 μm, respectively.
In the figure, D is the diameter of the small hole 2a, which is 25 μm in the embodiment.
The center-to-center distance P of a is 45 μm, and the minimum distance L between the small holes 2a and 2a is 20 μm. According to the experiment, if the above-mentioned symbols are used and the maximum distance between the adjacent small holes 2a is P, the relational expressions H ≧ 2P and V ≧ 2P + D are satisfied, and
In the case of a resolution of 8 lines / mm as in the embodiment, it is preferable to set the diameter D of the small holes 2a to D = 15 to 35 μm and P to P = 40 to 50 μm in order to obtain good print quality. Was needed for.

Special consideration is required to achieve good print quality even with the shape of the heating element 3 and to improve thermal efficiency during recording.

FIG. 11 shows the sectional shape of the heating element.

Here, the heating element 3 and the extraction electrode 121 are made of Al ₂
It is covered with a thin wear resistant insulating film 136 such as O ₃ .
By the way, the heating element 3 is rapidly heated by applying a voltage to generate bubbles, and the pressure causes the ink 4 in the small holes 2a filled with the ink 4 to be rapidly ejected and recorded. In the example, select the resistance of the heating element 3 to 300Ω,
Recording is performed by applying 24 V with a pulse width of 10 μsec to eject recording ink. At this time,
The energy consumed is about 2100 ergs / element.

This energy is almost constant when the thickness T of the gap 124 between the heating element and the film 2 is 3 μm or more, but T is 1
If it is 0 μm or more, the jetting output becomes poor and the printing quality becomes poor. It was also found that when T is 3 μm or less, the energy consumption of ink per heating element 3 is 2100 or more, and the smaller T is, the more energy is required. Therefore, in this embodiment, T = 3 μm.

Next, the following improvements have been made in terms of durability of the heating element 3.

That is, as proposed in Japanese Patent Application No. 59-11851, as a heating element (heating resistor), ruthenium oxide is the main component, and M (M is Ca, Sr, Ba, Pb,
At least one oxide selected from Bi and Tl is M
A metal oxide thin film containing / Ru (atomic ratio) of 0.6 to 2 is used.

By using the metal oxide thin film in this manner, it is not necessary to consider the change in resistance value due to oxidation as in the conventional case, it is possible to apply a large amount of power to raise the temperature, and the stability in long-term use is improved. Increase. Further, since this metal oxide thin film has a relatively high sheet resistance value, a relatively small current is required to obtain a high heat generation density.
Therefore, the current flowing through the conductive layer connected to the heating resistor is reduced as in the conventional case, and the heat generation from this portion can be reduced. Therefore, so-called print blurring that occurs during printing can be reduced. Further, since such a thin film has a positive resistance temperature coefficient, it has the advantages that the disadvantages of the SnO ₂ -based material can be improved, a large amount of electric power can be applied from the initial stage, and it is suitable for speeding up.

Next, the overall structure of the thermal head of the present invention will be described.
This will be described with reference to FIGS.

Although the structure of the heating element 3 has been described with reference to FIG. 11, in the present embodiment, the heating element 3 ... And the electrode portions 121A ... 121C ... Of the extraction electrode 121 are formed on the round glass rod 122 as a rod-shaped member. Further, this glass round bar 122 is of an end face type which is adhered to the end face of the support body 137.

Here, the thermal head 1 normally uses a ceramic substrate, but when the pattern of the heating elements 3 ... Or the wiring of the drive integrated circuit (hereinafter referred to as driver IC) 119 is provided on the surface as it is, the surface is rough and the pattern is broken. , Pattern contact, etc. occur. Therefore, a fine pattern cannot be obtained and a high dot density cannot be produced. In order to eliminate this, it is necessary to polish the ceramic substrate and to provide a glass glaze layer, which causes a high cost. In the present embodiment, since the heating elements 3 ... Are formed on the round glass rod 122, there is no need to form a special glass glaze layer or smooth processing, and the material cost is very low.

Further, since the aluminum plate 141 is used as the support 137 for supporting the glass round bar 122 and the glass / epoxy resin substrate 140 as the circuit board is used for mounting the driver IC 119, the size is 1/100 times that of the conventional ceramic substrate. The cost is 5 or less. However, no matter how cheap the glass / epoxy resin substrate 140 is, the driver IC 119 on the support 137 and the glass round bar 12 can be used.
A fine wiring pattern must be provided on the glass / epoxy substrate 140 in order to connect the lead electrode 121 on the wiring 2. However, glass / epoxy resin substrate 1
It is difficult with the existing technology to form such a fine pattern on the surface 40 by the etching method. Therefore, in order to provide a fine pattern, it is necessary to use a polished alumina substrate, which is inevitably expensive.

Therefore, in this embodiment, the driver IC 119 is adhered to the glass / epoxy resin substrate 140 near the glass rod 122, and the output terminal of the driver IC 119 is the drive signal side electrode portion 121C on the glass rod 122 as a conductive wire. Since it is not necessary to form a fine pattern on the glass / epoxy resin substrate 140 as described above by directly connecting by bonding with the connecting wire (gold wire) 170, the inexpensive mounting method can be achieved. On the other hand, driver IC1
Since the signal input side of 19 has about 1/5 the number of terminals as compared with the output side as shown in FIG. 14, even if a wiring pattern is formed on the glass / epoxy resin substrate 140, the pattern density does not become so high. Problems such as contact and disconnection do not occur.

By the way, it is estimated from the calculation of the energy consumption distribution that most of the energy (90% or more) consumed by the pulsed heating of the heating elements 3 is not used for ejecting the recording ink 4, but the film 2 It means that it is accumulated in etc. This accumulation warms the film 2 and the ink 4 and raises them to near the boiling point of the ink. Therefore, the situation of ink ejection changes depending on whether heat is accumulated or not. That is, the thermal history of recording causes a problem that the density of the recorded image becomes uneven. This problem cannot be completely covered by adjusting the current of the heating elements 3.
However, in this embodiment, the support 137 of the glass round bar 122 is used.
The aluminum plate 141 having good thermal conductivity is used for the glass round bar 12 so that the supporting surface of the aluminum plate 141 efficiently contacts the glass round bar 122.
It is an arcuate recess having the same curved surface as the second curved surface.

Further, in the present embodiment, as shown in FIG. 16, the drive power source side electrode portion 121A ... On the side opposite to the drive signal side electrode portion 121C.
Since they can be used in common, a certain distance from the heating elements 3 extends in a thin pattern as a thin pattern, and the end side portion thereof forms a common pattern 121B connected to each other. In the common pattern portion 121B, a pattern is formed along the circumference of the round glass rod 122 up to a portion in contact with the aluminum plate 141. Therefore, the heat generated by the heating elements 3 ... Is transmitted to the round glass rod 122, and at the same time, with a certain delay time, the drive power source side electrode portions 121A ...
It is transmitted to 1B.

Then, the glass round bar 122 and the driving power source side electrode portion 121A
The heat transmitted through the common pattern 121B is quickly transmitted to the aluminum plate 141 through the surface in contact with the aluminum plate 141 and diffused, so that the temperature of the glass rod 122 does not rise so much and temperature unevenness can be reduced.
It has become possible to significantly reduce the printing unevenness as described above.

Further, since the round glass rod 122 is used at the tip of the thermal head 1, the recording paper 8 can be easily separated after printing as compared with the thermal head 1 having a flat tip.

FIG. 15 is a sectional view of the thermal head 1 of this embodiment. 122 is a glass round bar, 3 ... is a heating element, 121A
..., 121C ... is an electrode part, 170 is a drive power source side electrode part 1
21 is a connection wire for connecting the output terminal of the driver IC 119, 171 is the common side electrode 121A and glass
Connection wires 174, 175, and 176 for connecting the drive power supply pattern 180 on the epoxy substrate 140 indicate positions for bonding the connection wires 170 and 171 respectively. Reference numeral 141 denotes an aluminum plate constituting the support 137, 140 denotes a glass / epoxy resin substrate on which the driver IC 119 is mounted, and 178 denotes an adhesive having good thermal conductivity for bonding the glass round bar 122 and the aluminum plate 141.

Further, in this embodiment, the driving signal side electrode portions 121C of the heating elements 3 ... Are taken out to one of the glass rods 122 and mounted on the glass / epoxy substrate 140.
119 are respectively connected.

Further, the driving power source side electrode portion 121A of the heating elements 3 ... Is taken out on the opposite side of the driving signal side electrode portion 121C .. and is connected to the common pattern portion 121B.

The common pattern portion 121B is formed with a pattern along the circumference of the round glass rod 122 so as to be in contact with the aluminum plate 141. Also, the common pattern portion 121B
Since the pattern end is arranged so as to be close to the end of the drive signal side electrode portion 121C, the drive signal and the power can be applied from one glass / epoxy substrate 140. Therefore, by lowering the impedance from the driving power source to the heating element 3, the voltage drop during driving can be minimized.

Further, as described above, since the driving power source side is divided into two parts, that is, the electrode portions 121A ... And the wide common pattern portion 121B each having a thin pattern substantially the same as the width of the heating element 3, ... By changing the length and the thickness of the electrode portions 121A, the resistance between the heating element 3 and the aluminum plate 141 is changed. That is, by appropriately selecting the thickness, length and width of the electrode portions 121A ...

As described above, according to the above-described embodiment, since the rod-shaped member is used, the manufacturing is easy and the material is inexpensive. In addition, since it does not require polishing to have flatness,
It is even cheaper. Glass round bar 1 with heating element 3 ...
22 and the aluminum plate 141 as the heat conducting member have a high degree of adhesion, and the glass round bar 12
The heat generated by the heating elements 3 on the upper part 2 is conducted to the aluminum plate 141, which is a heat conducting member, through the extraction electrode pattern of the heating elements 3 with an appropriate thermal resistance, so that heat accumulation is prevented. High-quality printing can be performed without uneven printing.

Further, since it is an end face type, a sufficient space around the head can be secured, so that it is possible to form a porous film cassette for a thermal ink jet recording device or a film cassette for a thermal transfer recording device, which simplifies the operation of the device. further,
Since there is only one substrate 140 on which the driver IC 119 for driving is mounted, the cost is low, there is no need for a special process for power supply, and the bonding process for only one surface is sufficient.

Although the thermal head of the present invention is applied to the bubble type ink jet recording apparatus in the above-described embodiments, the present invention is not limited to this and may be applied to, for example, a thermal color printer, a thermal transfer printer, or the like. Of course.

In addition, it goes without saying that the present invention can be variously modified and implemented without departing from the spirit of the present invention.

〔The invention's effect〕

INDUSTRIAL APPLICABILITY As described above, the present invention provides a heating element and a rod-shaped member provided on the peripheral surface with an extraction electrode for supplying electric power to the heating element, a support for mounting the rod-shaped member, and the extraction electrode. A drive integrated circuit that is connected to a drive signal side electrode portion and drives the heating element, or a circuit board having a wiring pattern, and is located on the side opposite to the drive signal side electrode portion of the extraction electrode. The end portion of the drive power source side electrode portion is extended along the outer periphery of the rod-shaped member, and the end portion is located in the vicinity of the end portion of the drive signal side electrode portion, and the power supply on the drive circuit board is provided. It is connected with the pattern for use. Therefore,
It is possible to provide a low-cost thermal head that has a relatively simple structure and can have a high packaging density, is not restricted by the apparatus and structure used.

[Brief description of drawings]

FIG. 1 is an explanatory view of a recording principle of a thermal ink jet recording apparatus to which the present invention can be applied, FIG. 2 (a) is a schematic vertical side view of the recording apparatus, and FIG. ,
FIG. 3 is a schematic vertical sectional front view, FIG. 4 (a) is a side view of the drive unit of the film moving mechanism, FIG. 4 (b) is a plan view of the drive unit of the film moving mechanism, and FIG. 5 is a perspective view of the film cartridge. 6 and 6 are perspective views of the film moving mechanism and the ink supply unit, FIG. 7 is a perspective view of the paper discharge roller unit, and FIG. 8 is a diagram showing the relationship between the diameter and pitch of the small holes and the shape of the heating element. FIG. 9 is a diagram for explaining the shapes of a multi-hole portion and a non-hole portion of the film, FIG. 10 is a diagram showing the relationship between film speed and recording density, FIG. 11 is a diagram showing the structure in the vicinity of the heating element, and FIG. A schematic side view showing an embodiment of the thermal bed of the present invention, FIG. 13 is a schematic plan view of the same, and FIG. 14 is a schematic perspective view of the same.
FIG. 15 is a schematic sectional view of a main part, and FIG. 16 is a schematic perspective view of the same. 1 ... Thermal head, 3 ... Heating element, 121 ... Extraction electrode, 121A ... Driving power source side electrode section, 121B
... Electrode pattern (common pattern), 121C ... drive signal side electrode section, 119 ... drive integrated circuit (driver I)
C), 122 ... Rod-shaped member (round glass rod), 137 ...
Support, 140 ... Circuit board (glass / epoxy resin board), 141 ... Aluminum plate, 170, 171 ...
Conductive wire (connection wire).

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8306-2C B41J 3/04 101 Z

Claims (3)

[Claims] 1. A rod-shaped member which is flat along the axial direction and has a curvature in the axial circumferential direction, a heating element disposed on a curved surface on the rod-shaped member, and provided on the rod-shaped member, An extraction electrode for supplying electric power to a heating element, a support for attaching the rod-shaped member, a drive circuit means for driving the heating element, which is connected to a drive signal electrode portion of the extraction electrode, and the extraction electrode The power supply means connected to the end portion of the drive power supply side electrode located on the opposite side of the drive signal electrode portion and extending along the outer periphery of the rod-shaped member is the same as the power supply means and the drive circuit means. A thermal head comprising: a substrate held on a flat surface. 2. The thermal head according to claim 1, wherein the end portions of the drive power source side electrode portions of the extraction electrodes are made common by the end portion and are connected to each other. 3. The thermal head according to claim 1, wherein the rod-shaped member has a circular cross section.