JP2002178550A - Thermal head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal head in which a heater can be set in parallel with a platen roller by simply pressing it against the platen roller. SOLUTION: The thermal head comprising a protruding heater arranged with heating elements in one direction is provided with a linear press member formed integrally with the heater to extend in the arranging direction of the heating elements and holding a thermal material along with a platen roller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a thermal head for performing thermal recording, and more particularly, to a thermal head capable of easily adjusting the parallelism of a thermal head to a platen roller.

[0002]

2. Description of the Related Art Thermal recording is used as recording means in various printers, plotters, fax machines, recorders and the like. In addition, thermal recording does not require a wet development process and has advantages such as easy handling. Therefore, in recent years, large and high-quality images such as CT diagnosis, MRI diagnosis, and X-ray diagnosis have been demanded. In applications where this is used, use for image recording for medical diagnosis is also being studied.

As is well known, in thermal recording, a thermal head having a heating element (glaze) in which heating elements are arranged in one direction (main scanning direction) is used, and a heating section of the thermal head is used as a thermal (recording) material. In a state of being slightly pressed, while relatively moving both in the sub-scanning direction orthogonal to the main scanning direction, energy is applied to each heating element according to the recorded image to generate heat, so that the heat-sensitive material The image is recorded by heating the layer. The heating element of the thermal head is usually
It is a minute linear projection extending in the main scanning direction and formed by laminating a glaze layer (heat storage layer), a heating element including a heating resistor and an electrode, a protective layer, and the like.

In a thermal recording apparatus using a thermal head, thermal recording is often performed using a roller (platen roller) having a rotation axis in the main scanning direction. In a thermal recording apparatus using a platen roller, a thermal head (heating element) is pressed against the platen roller via a thermal material,
By rotating the platen roller, the heat-sensitive material is held at a predetermined position, and the heat-sensitive material is nipped and conveyed between the thermal head (heating element) and the platen roller. Along with this nipping and conveying, heat-sensitive recording is performed by generating heat from each heating element according to the recorded image.

[0005]

In such a thermal recording apparatus, in order to perform high-quality thermal recording, the heating element of the thermal head and the platen roller (the rotation axis (axis)) thereof are precisely parallel. As the state, it is important that the heating element is pressed against the platen roller and the heating element is brought into contact with (presses) the heat-sensitive material in an appropriate linear shape.

For this reason, in the conventional thermal recording apparatus, it is necessary to adjust the parallelism of the thermal head (heating element) to the platen roller with high accuracy, which is troublesome. Also,
The degree of parallelism often goes out of order due to an external impact, repeated movement of the thermal head for performing thermal recording (normally, the thermal head and the platen roller are separated during non-recording), and the like. Each time, adjustment is required.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and only by pressing a thermal head (a heating element and a pressing member) against a platen roller, a heating element of the thermal head is applied to the platen roller. Therefore, it is an object of the present invention to provide a thermal head that can make the parallelism of the thermal heads unnecessary, so that it is not necessary to adjust the parallelism of the thermal head with respect to the platen roller.

[0008]

According to the present invention, there is provided a heat-sensitive material comprising a heat-generating element having a convex heat-generating element arranged in one direction, and a heat-sensitive material formed by the heat-generating element and a platen roller. A thermal head that performs thermal recording while nipping and transporting the recording medium, the linear head being parallel to the heating element, and formed integrally with the heating element, and pressed by a platen roller together with the heating element. A thermal head having a member is provided.

Preferably, the heating element is located downstream of the pressing member in the direction of transport of the heat-sensitive material. Further, the pressing member may be a heating element in which heating elements are arranged, and furthermore, the heating elements are arranged at the same pitch and shifted by a half pitch in the arrangement direction between the heating element and the pressing member. May be arranged.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a thermal head according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 conceptually shows a cross section of an example of a thermal recording apparatus using an example of a thermal head of the present invention. The thermal recording apparatus 10 is, for example, a cut sheet-shaped thermal recording film F (hereinafter, film F) of various sizes such as a half cut.
The recording head 14 performs thermal recording on a thermal recording material such as a thermal head 1 of the present invention.
8, a recording unit 20 for performing thermal recording on the film F, and a discharge tray 22 are provided.

The film F has a heat-sensitive recording layer formed on one side of a transparent polyethylene terephthalate (PET) support or the like.
A stack of about 0 sheets in a predetermined unit is accommodated in a dedicated magazine 24. The magazine 24 has a lid 26 which is locked by a known means in the closed state. When the lid is opened, the bottom plate 56 is lifted upward by a biasing member such as a spring, and the leading end of the entire film F stored in the magazine 24 in the transport direction is moved from the upper surface of the magazine 24 to the magazine 24. It will be in a protruding state.

The loading section 14 is a section for loading the magazine 24 into a predetermined position. The loading section 14 includes an insertion port 28 for inserting the magazine 24 into the apparatus, a feed roller 34, and opening / closing means for opening and closing the lid 26 of the magazine 24. It has a guide, a stopper, etc. (not shown) for loading the magazine 24 at a predetermined position.

The magazine 24 is inserted from the insertion port 28,
When the recording medium is loaded at a predetermined position by being guided by a guide or a stopper and a recording start instruction is issued, the opening / closing means opens the lid 26 of the magazine 24. As a result, the bottom plate 56 is lifted, and the film F projects to the upper surface. The feed roller 34 is in a standby state above as shown by the dotted line in the figure. When the lid 26 is opened, the feed roller 34 moves downward and contacts the upper surface of the film F shown by the solid line in the figure. It will be in contact. Next, as the feed roller 34 rotates, the film F is discharged from the magazine and supplied to the transport unit 16. When the film F is completely discharged from the magazine 24, the feed roller 34 is raised to return to the original position shown by the solid line, and the opening / closing means closes the cover 26 of the magazine 24.

The transport section 16 is transported from the magazine 24 by the feed roller 30 and transported by the film F
Is transported to the recording unit 20, and the transport guide 3
4 and a pair of transport rollers 36 and the like. The upper roller of the transport roller pair 36 serves as a cleaning roller, and the film F is transported, and foreign matter attached to the surface thereof is removed.

The recording section 20 is provided with the thermal head 1 of the present invention.
8, a portion for performing thermal recording on the film F. In addition to the thermal head 18, the platen roller 3
8, transport guides 40 and 42, a discharge roller pair 44, a cooling fan (not shown) for the thermal head 18, and the like.

FIG. 2 is a partially enlarged view of the recording section 20.
2A is a schematic diagram (hereinafter referred to as a front view) viewed from the main scanning direction in the same direction as FIG.
(B) is a schematic plan view. The thermal head 18 is
A thermal head main body 64 having a heating element 60 and a pressing member 62 extending in the direction (main scanning direction), and a heat sink 66 fixed to the thermal head main body 64. Basically, it has the same configuration as a known thermal head. The platen roller 38 is also a roller having a rotating shaft 38a (axis) extending in the main scanning direction, similar to the one arranged in a normal thermal recording apparatus.

The heating element (glaze) 60 is moved in the main scanning direction (in FIG. 1 and FIG.
(B) is similar to a known thermal head having heating elements arranged in the direction of the arrow x), for example, a heat storage layer (glaze layer), a heating element having a heating resistor and an electrode, a protective layer, and the like. And linear projections extending in the main scanning direction. The pressing member 62 is a linear projection formed on the thermal head main body 64 and parallel to the heating element 60. When performing thermal recording on the film F, the pressing member 62 is pressed by the platen roller 38 together with the heating element 60, and sandwiches the film F together with the platen roller 38 similarly to the heating element 60.

In the recording section 20, the heating element 60 is pressed against the side surface of the platen roller 38 via the film F, similarly to a thermal recording apparatus using a normal thermal head.
By rotating the platen roller 38, the heating element 60
While the film F is being nipped and conveyed by the platen roller 38 and the heating elements of the heating element 60 generate heat in accordance with the recorded image, the film F is colored to record an image. Here, in order to record a high-quality image, it is important that the heating element 60 and the platen roller 38 (axis) are pressed accurately in parallel, and the heating element 60 contacts the film F in a straight line. As described above, the parallelism of the thermal head with respect to the platen roller 38 needs to be adjusted with high precision as described above.

On the other hand, the thermal head 18 of the present invention
Is formed integrally with the heating element 60 and
The heating member 60 and the pressing member 62 are pressed by the platen roller 38 during recording. That is, two linear projections parallel to the platen roller 38 are
8 is pressed. Therefore, the heating element 60 and the pressing member 6 which are two linear convex portions extending in the main scanning direction are provided.
2 is pressed against the platen roller 38, the thermal head 18 is guided by the two convex portions, and the heating element 60 and the pressing member 62 are parallel to the platen roller 38, and the heating element 60 is pressed in parallel to the platen roller 38. it can. That is, according to the thermal head of the present invention, it is not necessary to adjust the parallelism of the thermal head 18 with respect to the platen roller 38, and the labor and cost can be reduced accordingly.

The shape and size of the pressing member 62 are not particularly limited. The pressing member 62 has a linear shape parallel to and integrated with the heating element 60. When the heating element 60 is pressed by the platen roller 38, The film F is pressed by the rollers 38 and
Any material can be used as long as it can hold (thermosensitive recording material). Further, there is no limitation on the forming material and the like. Therefore, the pressing member is
It is not limited to being a convex member as in the illustrated example,
If the film F is integrally formed with the heating element 60, for example, it has a rotation axis (axis) extending in the main scanning direction, forms a roller pair with the platen roller 38, and nips and conveys the film F. It may be a roller. Further, it is not necessary to have a continuous linear shape, and it may be divided into a plurality of portions in the main scanning direction, or may be a dotted line shape.

In order to stabilize the pressing of the platen roller 38 by the heating element 60 and the pressing member 62, the vector of the pressing force by both of them is directed to the center of the platen roller 38 (the rotation shaft 38a) as much as possible. Is preferred. Therefore, the heating element 60 and the pressing member 62
Both preferably have a shape that is directed toward the center of the platen roller 38 when pressed by the platen roller 38. For example, when pressed by the platen roller 38, they protrude toward the rotation shaft 38a. It is preferable to have such a shape.

In the illustrated example, the thermal head 18
Has a heating element 60 on the downstream side in the transport direction, but the present invention is not limited to this. However, in the present invention, the film F is transported between the heating element 60 and the pressing member 62 in close contact with the platen roller 38. Also,
In general, the film F tends to curl immediately after being heated. Accordingly, in order to prevent the occurrence of curl due to the curvature after heating and to correct the curl caused by being conveyed in close contact with the platen roller 37, the heating element 60 is
It is preferable to dispose it downstream of the pressing member 62 as in the illustrated example.

Further, in the present invention, the pressing member 62
Or a heating element. In this case, it is preferable that the two heating elements have the same arrangement pitch of the heating elements (pixels), and the heating elements are arranged so as to be shifted from each other by a half pitch in the main scanning direction. Thus, thermal recording with a higher pixel density can be performed, and a higher quality image can be obtained.

In such a recording section 20, during non-recording, the thermal head 18 is moved upward, the heating element 60 and the pressing member 62 are separated from the platen roller 38, and the platen roller 38 is Has stopped.

As described above, the film F taken out of the magazine 24 and conveyed by the feed roller 30 and the conveying roller pair 36 is conveyed, and when conveyed to a predetermined position, the thermal head 18 is lowered to generate heat. The body 60 and the pressing member 62 are pressed by the platen roller 38 (or pressed via the film F), and the platen roller 38 starts rotating at a predetermined timing,
The film F is nipped and conveyed by the heating element 60 and the pressing member 62 and the platen roller 38. here,
Since the thermal head 18 of the present invention has the pressing member 62 which is a linear convex parallel to the heating element 60, the heating element 60 can be attached to the platen roller 38 even if the parallelism is not adjusted particularly accurately. As described above, it is appropriately pressed in parallel.

At the time of the nipping and transporting, each of the heating elements of the heating element 60 generates heat in accordance with the recorded image, so that the film F is colored and an image is recorded. The film F on which the image is recorded is conveyed to the discharge roller pair 44 while being guided by the conveyance guide 42, and is discharged to the discharge tray 22 as a hard copy on which the image is formed. When recording is completed, the thermal head 18 rises, the heating element 60 and the pressing member 62 are separated from the platen roller 38,
Further, the platen roller 38 stops.

Although the thermal head of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various improvements and modifications may be made without departing from the gist of the present invention. Of course.

[0029]

As described in detail above, the thermal head according to the present invention does not need to adjust the parallelism with the platen roller with high precision, but only presses the heating element against the platen roller. , And the labor and time required for the adjustment can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of an example of a thermal recording apparatus using a thermal head of the present invention.

FIG. 2 is a conceptual diagram of an example of a thermal head according to the present invention.
(A) is a front view, (B) is a plan view.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 thermal recording device 14 supply unit 16 transport unit 18 thermal head 20 recording unit 22 discharge tray 24 magazine 26 lid 28 insertion port 30 feed roller 34, 40, 42 transport guide 36 transport roller pair 44 discharge roller pair 56 bottom plate 60 heating element 62 pressing member 64 thermal head main body 66 heat sink

Claims (4)

[Claims] 1. A thermal head for performing thermal recording while holding a heat-sensitive material between a heat-generating element and a platen roller, wherein the heat-generating element has a convex heat-generating element arranged in one direction. A thermal head, comprising: a pressing member formed in a straight line parallel to the heating element and integrally with the heating element and pressed by a platen roller together with the heating element. 2. The thermal head according to claim 1, wherein the heating element is located downstream of the pressing member in a direction in which the heat-sensitive material is conveyed. 3. The thermal head according to claim 1, wherein the pressing member is a heating element in which heating elements are arranged. 4. A heating element comprising the heating element and the pressing member,
The thermal head according to claim 3, wherein the thermal heads are arranged at the same pitch and shifted by a half pitch in the arrangement direction.