JPH03136885A - Thermal head supporting mechanism in thermal printer apparatus - Google Patents

Abstract

PURPOSE:To enable image recording with high accuracy by supporting a first supporting shaft along a main scanning direction of a thermal head by a first and a second pivot bearings, and pressing the first supporting shaft towards a main scanning direction by use of a first pressing member thereby to restrict the displacement at the recording time of an image or the like. CONSTITUTION:A thermal head supporting body 50 supporting a thermal head 30 is held between side plates 34a and 34b via pivot bearings 42a, 42b by a first supporting shaft 36. The first supporting shaft 36 is pressed to the side of the pivot bearing 42a by a wave washer 44 held between a holder 40b and the pivot bearing 42b. Therefore, the thermal head 30 is positioned at the side of the side plate 34a, and is never shifted in a main scanning direction when an image is recorded. Moreover, the thermal head 30 is pressed to a sub scanning direction via a thrust bearing 54a by a wave washer 52 mounted in a second supporting shaft 48 and therefore positioned at the side of a thrust bearing 54b, thus without being shifted in the sub scanning direction when an image is recorded.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a thermal printer device that records images, etc. on a heat-sensitive material using a thermal head in which heating elements are arranged in the main scanning direction. The present invention relates to a thermal head support mechanism configured to suppress fluctuations in the main scanning direction and the sub-scanning direction.

[Prior Art] For example, in the medical field, various medical diagnostic devices such as an X-ray imaging device, an ultrasound imaging device, an X1ICT, and a DF are used to diagnose affected areas. In this case, these diagnostic devices can easily and accurately perform diagnostic work by displaying an image of the affected area on a CRT monitor or the like.

Incidentally, in the medical image diagnostic apparatus, it is desirable that image information displayed on a CRT monitor or the like be selectively output as a hard copy onto a record carrier. As a printer device for this purpose, a thermal printer device that forms a visible image by heating a heat-sensitive film according to image information is known.

In this thermal printer device, an image is recorded by conveying a thermal film in a sub-scanning state while being sandwiched between a thermal head having heating elements arranged in the main-scanning direction and a platen roller. In this case, in order to accurately record an image on the thermosensitive film, it is necessary that the thermal head has a structure that does not move in the main scanning direction and the sub-scanning direction.

[Problems to be Solved by the Invention] However, the thermal head is usually configured to be able to come into contact with and separate from the platen roller in order to insert a heat-sensitive film between the thermal head and the platen roller. has been done. Further, the thermal radar is configured to be able to swing around the sub-scanning direction so that it always contacts the heat-sensitive film in a constant state in its longitudinal direction (main-scanning direction). Due to the wobbling of these movable parts, the thermal head may vibrate due to vibrations of the drive system constituting the thermal printer device during image recording, and the contact position with respect to the heat-sensitive film may change. Furthermore, part of the heat-sensitive film heated by the thermal head may stick to the thermal head side, and when this stuck heat-sensitive film is conveyed in the sub-scanning direction, the thermal There is a possibility that the position of the head may change, causing unevenness in the obtained image.

The present invention has been made to overcome the above-mentioned disadvantages, and is a thermal head support in a thermal printer device that suppresses fluctuations during recording of images, etc. of the thermal head, and thereby enables highly accurate image recording. The purpose is to provide a mechanism.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention uses a thermal head in which heating elements are arranged in the main scanning direction and a platen roller to sandwich and heat a heat-sensitive material that is conveyed in the sub-scanning direction. In a thermal printer device that records images, etc., the thermal head can come into contact with or separate from the platen roller by rotating around a first support shaft along the main scanning direction. The first support shaft is supported such that one end thereof is supported by a first pivot bearing, and the other end thereof is supported by a second pivot bearing. The second support shaft is configured to be pressed toward the one end by a first pressing member via a pivot bearing, and the second support shaft has one end attached to the first support shaft, and the one end and the other end of the second support shaft. The thermal head is pivotally supported between installed thrust bearings, and the thermal head is configured to be pressed by a second pressing member through one thrust bearing toward the other thrust bearing.

[Operation] In the thermal head support mechanism in the thermal printer device of the present invention configured as described above, the first support shaft of the thermal head along the main scanning direction is supported by the first and second pivot bearings, and the first support shaft of the thermal head along the main scanning direction is supported by the first and second pivot bearings. By configuring it to press in the main scanning direction using the first pressing member, fluctuations in the main scanning direction are suppressed, and between the thrust bearings attached to the second support shaft along the sub-scanning direction of the thermal head. the thermal head is pivotally supported, and the second. By configuring the thermal head to be pressed in the sub-scanning direction using a pressing member, fluctuations in the sub-scanning direction are suppressed.

In this case, the thermal head can be moved away from the platen roller by rotating around the first support shaft, and is also accurately pressed to a predetermined position on the heat-sensitive material during recording, thereby achieving high accuracy. This makes it possible to record images of different sizes.

[Embodiments] A preferred embodiment of a thermal head support mechanism in a thermal printer device according to the present invention will be described in detail below with reference to the accompanying drawings.

1 and 2 show the structure of a thermal head support mechanism according to this embodiment, and this thermal head support mechanism is applied to the thermal printer device IO shown in FIG. 3.

Inside the casing 12 constituting the thermal printer device 10 are a transport recording section 14 that transports the thermal film F wound into a roll and records an image thereon, and a control section that controls the operation of the thermal printer device 10. It is divided into 16 parts.

In this case, as the heat-sensitive film F, a photofixing type film based on polyester is used.

The transport recording section 14 includes an image recording section 18 that forms a predetermined image by heating the thermosensitive film F, a cutter section 20 that cuts the thermosensitive film F into a predetermined length, and a cutter section 20 that irradiates the thermosensitive film F with ultraviolet rays. The image fixing section 22 includes an image fixing section 22 that fixes the image.

Thermal film F wound into a roll and the image recording section 18
A pair of feed rollers 24 for conveying the thermal film F to the image recording section 18 are disposed between the two. Note that a film detection sensor 26 is provided in front of the feed roller 24.

The image recording unit 18 includes a platen roller 28, a thermal head 30 that is pressed against the platen roller 28 via a heat-sensitive film F, and a thermal head support mechanism 32 that supports the thermal head 30. By bringing the heat-sensitive film F into contact with the platen roller 28 along its outer peripheral surface, the platen roller 28 moves the heat-sensitive film F in the main scanning direction perpendicular to FIG. 3 (direction of arrow X in FIGS. 1 and 2). This is to maintain flatness.

The thermal head 30 has a large number of heating elements 31 arranged in the main scanning direction, and heats the thermal film F by selectively driving each heating element 31, thereby recording an image.

On the other hand, the thermal head support mechanism 32 according to this embodiment is
It is constructed as shown in FIGS. 1 and 2. That is, side plates 34a are provided on both sides in the main scanning direction within the conveyance recording section 14.
, 34b are arranged, and these side plates 34a, 34
A first support shaft 36 extending along the main scanning direction is pivotally supported between the positions b. The first support shaft 36 has cone-shaped cones 38a, 38b at both ends thereof, and each cone 38a, 38b
are supported by pivot bearings 42a, 42b fixed to side plates 34a, 34b with holders 40a, 40b. In this case, the holder 40 fixed to the side plate 34b
b and the pivot bearing 42b, as shown in FIG.
A wave washer 44 is interposed as a pressing means for pressing. In addition, inside the first support shaft 36, cones 38a and 38b
Ball bearings 46a and 46b, which are rotatable about an axis, are mounted in the vicinity of the .

One end of a second support shaft 48 extending in the sub-scanning direction (arrow Y direction) is attached to the center of the first support shaft 36, and the thermal head 30 is attached to the second support shaft 48. A thermal head support 50 is pivotally mounted. The thermal head support 50 is composed of a plate that is elongated in the main scanning direction, and is attached to the first support shaft 36 at both ends of one side 50a of the thermal head support 50 in the sub-scanning direction. The ball bearings 46a and 46b that are rotated are in contact with each other.

Further, in the second support shaft 48 inserted through the center of the thermal head support 50, a wave washer 52 as a pressing means is provided between the first support shaft 36 and the side surface 50a of the thermal head support 50. A thrust bearing 54a is mounted therebetween. Further, a thrust bearing 54b is also installed between the other end of the second support shaft 48 and the other side surface 50b of the thermal head support 50.

In this way, the thermal head support 50 is attached to the first support shaft 36.
It is configured to be rotatable in the direction of the arrow B about the center, and is configured to be swingable in the direction of the arrow B about the second support shaft 48 .

Note that the thermal head 30 of the thermal head support 50
The other parts of coil springs 58a and 58b, one end of which is supported by brackets 56a and 56b, are abutted on both sides in the main scanning direction in the upper surface facing the upper surface. Further, a bracket 60 having an oval-shaped cross section is attached to the side surface 50b of the thermal head support 50, and an eccentric cam 62 can come into contact with this bracket 60. In this case, the thermal head support 50 can be separated from the platen roller 28 via the bracket 60 under the action of the eccentric cam 62. Note that a fan 63 for cooling the image recording section 18 is further provided on the upper surface of the thermal head support 50.

On the other hand, the cutter part 20 is composed of a fixed blade 64 and a rotary blade 66, and cuts the heat-sensitive film F by rotating the rotary blade 66. Note that a film detection sensor 68 is provided between the image recording section 18 and the cutter portion 20.

The image fixing section 22 includes a pair of ultraviolet lamps 70a and 70b disposed opposite to each other on both sides of the heat-sensitive film F, and a reflector 72a made of vapor-deposited aluminum or the like is provided on the back side of the ultraviolet lamps 70a and 70b. ? 2b is arranged.

Note that a film detection sensor 74 for detecting the conveyance state of the heat-sensitive film F is provided between the cutter portion 20 and the image fixing gB22.

Two sets of feed rollers 76 and 78 are arranged above the image fixing section 22, and these feed rollers 7
A film detection sensor 80 for detecting the conveyance state of the heat-sensitive film F is provided between 6 and 78. Further, a film detection sensor 81 is provided immediately after the feed roller 78 to detect the conveyance state of the heat-sensitive film F.

A film receiving portion 82 is provided at the rear stage of the feed roller 78, and an extension tray 86 is further provided in this film receiving portion 82 and projects outward through an opening 84 defined in the housing 12. It will be done.

The thermal printer device according to this embodiment is basically constructed as described above, and its operation and effects will be explained next.

In this case, the thermal printer device IO is connected to various medical image diagnostic devices (not shown), and a desired image is recorded as a hard copy on the thermosensitive film F based on instructions from a doctor or the like.

Therefore, first, the thermal film F wound into a roll is loaded into the thermal printer device IO, and the leading end of the film is passed between the platen roller 28 and the thermal head 30 in the image recording section 18 via the feed roller 24. insert it into the In this case, if the eccentric cam 62 is rotated under the action of a rotation means (not shown), the bracket 60 will be displaced, and the thermal head support 50 will be rotated by the coil springs 58a, 58.
It rotates in the direction of the arrow about the first support shaft 36 against the elastic force b. Thereby, a predetermined amount of gap is defined between the thermal head 30 and the platen roller 28. Therefore, after inserting the leading end of the heat-sensitive film F through the gap to the cutter part 20, the eccentric cam 62 is rotated again to stretch the heat-sensitive film F between the platen roller 28 and the thermal head 30. will be established.

Next, the platen roller 28 and the feed roller 24
When the film detection sensor 80 detects the transport of the thermosensitive film F, the rear end of the thermosensitive film F is cut by rotating the rotary blade 66 that constitutes the cutter part 20. , feed roller 76.78
The cut thermal film F is discharged onto the film receiving section 82.

At this time, the film detection sensor 81 detects that the heat-sensitive film F has been completely discharged to the film receiving section 82. At the same time, the platen roller 28 and the feed roller 24 are rotated by a predetermined amount in opposite directions to set the leading end of the subsequent thermal film F at a predetermined position of the thermal head 30 . Next, the platen roller 28 and the feed roller 24 are rotated in the forward direction, and the thermal head 30 is driven to start recording an image on the thermal film F.

In this case, the thermal head support 50 that supports the thermal head 30 is pivotally supported by the first support shaft 36 between the side plates 34a and 134b via pivot bearings 42a and 42b. This first support shaft 36 is pressed toward the pivot bearing 42a by a wave washer 44 sandwiched between the holder 40b and the pivot bearing 42b. Therefore, the thermal head 30 is positioned on the side plate 34a side, and the thermal head 30 does not move in the main scanning direction when recording an image. Also,
Since the thermal head 30 is pressed in the sub-scanning direction via the thrust bearing 54a by the wave washer 52 attached to the second support shaft 48, it is positioned on the thrust bearing 54b side and is pressed in the sub-scanning direction when recording an image. There is no change. Furthermore, the thermal head 30 is supported by a ball bearing 46a146b mounted on the first support shaft 36 and thrust bearings 54a, 54b mounted on the second support shaft 48, and is moved in the direction of arrow B around the second support shaft 48. It is configured to be able to swing freely,
Its upper surface is urged toward the platen roller 28 by a coil spring 58a158b. Accordingly,
The heating element 31 of the thermal head 30 always contacts the heat-sensitive film F with a uniform pressing force in the main scanning direction.

As described above, when the heat-sensitive film F is heated by the heating element 31, the thermal head 30 moves in the main scanning direction (direction of the arrow And there is no fluctuation in the sub-scanning direction (arrow Y direction). Further, since the thermal head 30 is swingable in the direction of arrow B, the pressure contact force between the heating element 31 and the heat-sensitive film F is always kept uniform in the main scanning direction. As a result, an image is accurately recorded on the thermosensitive film F.

Next, the thermal film F on which the image has been recorded is cut into a portion 2 of the cutter.
0 to the image fixing section 22, and the image fixing section 2
The image is fixed on the heat-sensitive film F by the ultraviolet lamps 70a and 70b constituting the second part. Next, the heat-sensitive film F is conveyed by feed rollers 76, 78 and discharged from the film receiving section 82 through the opening 84 onto the extension tray 86.

[Effects of the Invention] As explained above, according to the thermal head support mechanism according to the present invention, since the thermal head is pressed and held in the main scanning direction by the pressing means via the pivot bearing, the thermal head is held in the main scanning direction during image recording. The head does not move in the main scanning direction. Further, since the thermal head is held pressed in the sub-scanning direction by the pressing means via the thrust bearing, it does not move in the sub-scanning direction. As a result, the thermal head does not move in the main scanning direction and sub-scanning direction when recording images.
Extremely accurate image recording can be performed.

[Brief explanation of the drawing]

FIG. 1 is a perspective explanatory diagram of the configuration of a thermal head support mechanism according to the present invention, FIG. 2 is a plan explanatory diagram of the thermal head support mechanism according to the present invention, and FIG. 3 is a diagram in which the thermal head support mechanism according to the present invention is incorporated. A schematic configuration diagram of a thermal printer device. FIG. 4 is an enlarged sectional view of a main part of a thermal head support mechanism according to the present invention. 10... Thermal printer device 14... Conveyance recording section 16... Control section 18.
...Image recording section 20...Cutter part 22...
・Image fixing section 28...Platen roller 30・
...Thermal head 31...Heating element 32...
Thermal head support mechanism 36...First support shafts 42a, 42b...Pivot bearing 44...Wave washers 46a, 46b...Ball bearing 48...Second
Support shaft 50...Thermal head support 52...Wave washers 54a, 54b...Thrust bearings 58a, 58
b...Coil swing lJ ring 62...Eccentric cam
F...thermal film

Claims (1)

[Claims] (1) In a thermal printer device that records images, etc. by sandwiching and heating a heat-sensitive material that is conveyed in the sub-scanning direction between a thermal head in which heating elements are arranged in the main-scanning direction and a platen roller, the thermal head is , is supported so as to be able to come into contact with or separate from the platen roller by rotating around a first support shaft along the main scanning direction, and swing around a second support shaft along the sub-scanning direction. The first support shaft is configured such that one end thereof is pivotally supported by a first pivot bearing, and the other end thereof is pressed toward the one end side by a first pressing member via a second pivot bearing. The second support shaft has one end attached to the first support shaft, supports the thermal head between thrust bearings attached to the one end and the other end, and supports one thrust bearing. A thermal head support mechanism in a thermal printer device, characterized in that the thermal head is configured to be pressed by a second pressing member to the other thrust bearing side via the second pressing member.