JP2000062995A - Recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep a gap between a recording head and a sheet material proper all the time irrespective of the thickness of the sheet material to be used. SOLUTION: This device is provided with a platen 11 which guides and supports the underside of a sheet material 7 at a position where the platen 11 faces a recording head 1 recording an image on the sheet material 7, a feeding side driving roller 8 disposed on the upstream side of the platen 11 in the direction of conveyance and coming into contact with the underside of the sheet material 7 for conveyance, a register roller 9 fixed to the upper limit position of the recording head 1 side of the sheet material 7 and rotating with the feeding side driving roller 8, a delivering side driving roller 20 disposed on the downstream of the platen 11 in the direction of conveyance and coming into contact with the underside of the sheet material 7 for conveyance, and a delivering spur 21 fixed to the upper limit position of the recording head 1 side of the sheet material 7 and rotating with the delivering side driving roller 20. The feeding side driving roller 8 and the delivering side driving roller 20 are formed so as to be capable of moving downward according to the thickness of the sheet material 7, and the platen 11 is formed so as to operate with the movement in the direction of the thickness of the sheet material 7 of the feeding side driving roller 8 and the delivering side driving roller 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device such as a printer, a copying machine or a facsimile which records an image on a sheet material.

[0002]

2. Description of the Related Art In many conventional recording apparatuses, a position-fixed conveying roller (particularly a driving roller) is arranged at a position facing a recording head. When a sheet material thicker than a normal sheet material is used in the recording apparatus having such a configuration, the operator moves the recording head in the direction of retracting from the sheet material with a lever and then starts the recording operation. Is used (conventional example 1).

Further, an idle roller which can be moved up and down is arranged slightly upstream of the platen at the position opposite to the recording head in the conveying direction, and the idle roller is provided as a fixed drive roller on the opposite side (recording head side). There is a configuration in which an idle roller that is abutted by a pressing means and is also vertically movable downstream in the transport direction is also abutted against a position-fixed drive roller on the opposite side (recording head side). In the case of this configuration, when using a sheet material that is thicker than a normal sheet material, each idle roller on the lower side (platen side) moves downward when the sheet material is sandwiched by each roller pair, The gap between the recording head and the sheet material is maintained in an appropriate state (conventional example 2).

[0004]

However, in the above-mentioned conventional example 1, the operator has to manually make settings for each paper type. If a thick sheet material is used without proper setting, the sheet material and the recording head may come into contact with each other, disturbing the image and damaging the recording head.

Further, in Conventional Example 2, even if the idler roller on the platen side moves downward depending on the thickness of the sheet material, the platen at the position facing the recording head remains fixed, so that it is not so much. If a thick sheet material is used, the platen may interfere. Therefore, the thickness of the sheet material used is limited. If a sheet material with a thickness exceeding this limit is used, it is necessary to lower the platen installation position by that thickness, but with this configuration, it is possible to record a sheet material with a normal thickness. The gap with the recording head may not be guaranteed.

Therefore, an object of the present invention is to provide a recording apparatus capable of always maintaining a proper gap between the recording head and the sheet material regardless of the thickness of the sheet material used.

[0007]

A typical constitution of the present invention for achieving the above object is a platen for guiding and supporting a back surface of a sheet material at a position facing a recording means for recording an image on the sheet material, A first transport roller disposed upstream of the platen in the transport direction and configured to contact and transport the back surface of the sheet material;
A first driven roller that is fixed to an upper limit position on the recording unit side of the sheet material and that is rotated by being driven by the first transport roller; and a first driven roller that is disposed downstream of the platen in the transport direction and is in contact with the back surface of the sheet material. A first driven roller and a second driven roller which are fixed to an upper limit position of the sheet material on the recording unit side and which are driven by the second driven roller to rotate. The second transport roller is configured to be movable downward according to the thickness of the sheet material, and
The platen is configured to operate following the movement of the first transport roller and the second transport roller in the thickness direction of the sheet material.

With the above structure, the first transport roller and the second transport roller move downward according to the thickness of the sheet material to be used, and follow the movement of the first transport roller and the second transport roller. Since the platen also moves downward, it is possible to always maintain a proper gap between the recording means and the sheet material regardless of the thickness of the sheet material used.

Further, a first spring member for pressing the first conveying roller toward the first driven roller and a second spring member for pressing the second conveying roller toward the second driven roller, By adopting a configuration in which the first transport roller and the second transport roller are pressed via the platen, it becomes possible to vertically move each transport roller and the platen with a simple configuration, and each transport The height difference between the roller and platen is minimized.

Further, by arranging the platen rotatably on the frame member holding the first conveying roller, the platen can be downsized and the stability of the operation can be enhanced. In addition, the structure of the drive system that drives the first transport roller that serves as the main transport roller can be configured with high accuracy.

Further, a platen for guiding and supporting the back surface of the sheet material at a position opposite to the recording means for recording an image on the sheet material, and a platen arranged upstream of the platen in the carrying direction to contact the back surface of the sheet material for carrying. A first conveying roller; a first assist roller that rotates following the first conveying roller; a second conveying roller that is arranged downstream of the platen in the conveying direction and that is in contact with the back surface of the sheet material; A second assist roller that is fixed to a position that is the upper limit of the recording material side of the sheet material and that rotates following the second transport roller, and moves the second transport roller downward depending on the thickness of the sheet material. In addition to being movable, the platen is configured to operate following the movement of the second transport roller in the thickness direction of the sheet material.

With the above construction, the second conveying roller moves downward according to the thickness of the sheet material to be used, and the platen also moves downward following the movement of the second conveying roller, which is inexpensive. With a simple structure, it is possible to always maintain a proper gap between the recording means and the sheet material.

Further, the second spring member for pressing the second conveying roller in the second driven roller direction presses the second conveying roller via the platen, so that the constitution is simple. It is possible to vertically move the second conveying roller and the platen, and the height error between the second conveying roller and the platen is minimized.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a recording apparatus to which the present invention is applied will be specifically described below with reference to the drawings. In the following description, an inkjet recording device is illustrated as an example of the recording device.

[First Embodiment] A recording apparatus according to the first embodiment will be described in detail with reference to FIGS. FIG. 1 is a perspective view in which a part of a platen portion of the recording apparatus according to the first embodiment is cut away, and FIG. 2 is a schematic sectional view thereof.

In FIG. 1, reference numeral 1 denotes a recording head for ejecting ink droplets to record on a recording medium, which is mounted on a carriage 2. The recording head 1 and the carriage 2 are driven by a carriage motor (not shown) via a timing belt 6. The right end side of the carriage 2 in the drawing is a guide rail 3 and the left end side of the carriage 2 in the drawing is its end. A guide roller 4 projecting from the portion is supported by a support rail 5 and scans the support rail 5 and the guide rail 3.

On the other hand, the sheet material 7 as a recording medium is fed by a feeding mechanism (not shown) to the nip position of the registration roller pair 10 formed by the feeding-side drive roller 8 and the registration roller 9, and skewed. Etc. are corrected. The feeding-side driving roller 8 which is the first conveying roller is pressed against the registration roller 9 by the roller pressing springs 31 arranged on the left and right (both ends in the width direction orthogonal to the conveying direction), and the thickness of the sheet material used. It is configured to be movable up and down according to the height. Further, in accordance with the rotational driving of the feeding side driving roller 8, the registration roller 9
Is driven to rotate.

After that, the sheet material 7 is passed through a space between the platen 11 and the sheet material pressing plate 12 which face the recording head 1 by the rotation of the registration roller pair 10 driven by a motor (not shown), and a recording area is formed. Be transported to.

The platen 11 has ribs 13 forming a plurality of convex portions arranged at a predetermined (20 to 40 mm) pitch parallel to the carrying direction on the carrying surface. Further, the platen 11 is in pressure contact with the feed side drive roller 8 by the roller pressure contact spring 31 on the upstream side in the conveyance direction, and is in pressure contact with the discharge side drive roller 20 by the roller pressure contact spring 32 in the downstream side in the conveyance direction. The platen 11 is also configured to move up and down as the roller moves up and down.

The sheet pressing plate 12 has a thickness of 100 to 200.
The platen 11 is made of an elastic material such as polyester film having a thickness of about μm, and moves toward the downstream side in the sheet material conveying direction.
It is arranged with an inclination so that it is closer to the side. Further, the planar shape of the sheet material pressing plate 12 is provided with projections 16 projecting at positions corresponding to the recesses 15 between the plurality of ribs 13 of the platen 11, and the tips of the projections 16 are ribs.
It is arranged so as to extend from 13 to the lower surface, and the horizontal portion 17 is arranged so as to stay above the rib 13. That is, the protrusion 16
The sheet material pressing plate 12 having the above functions as a displacement imparting member that displaces the sheet material 7 on the upstream side of the recording area to the platen 11 side.

Therefore, when the sheet material 7 is thin and has low rigidity (for example, plain paper having a thickness of about 70 μm), when the sheet material 7 passes between the platen 11 and the sheet material pressing plate 12, the ribs 13 and the protrusions are formed.
The rib 16 has a wavy shape which becomes the apex at the rib 13 portion and becomes a valley (displaced to the platen 11 side) between the protrusions 16, that is, between the ribs 13 (see FIG. 3).

On the other hand, when the sheet material 7 is thick and has high rigidity (for example, a paper having a thickness of about 200 μm), when passing between the platen 11 and the sheet material holding plate 12, the sheet material holding plate is pressed.
The sheet 12 is bent and the projection 16 no longer fulfills the function of generating a wavy shape, and the sheet material 7 is conveyed flat. At this time, the feeding-side drive roller 8 moves downward by the amount corresponding to the paper thickness, and following this, the upstream side portion of the platen 11 also moves downward. Further, when the sheet material 7 plunges into the discharge side drive roller 20, the discharge side drive roller 20 also moves downward, and following this, the downstream side portion of the platen 11 also moves downward.

Further, in the downstream of the recording area, the sheet material pressing plate 12 is positioned at a position relative to the protrusion 16 (the protrusion 16 along the conveying direction).
Spur 18 is arranged and mounted on the rotary shaft 19 so as to respectively project into the recesses 15 between the ribs 13). The rotating shaft 19 is rotationally driven by a motor (not shown), and rotates the plurality of spurs 18 at the same speed as the conveying speed so that the spurs 18 do not become a resistance when the sheet material 7 rushes in. The "spur" referred to here is a gear-like one that has sharp protrusions all around the outer periphery, and assists the conveyance of a recording medium (sheet material) with a minute area formed by a plurality of protrusions.

With the above construction, the spur 18 forms the same movement as the protrusion 16 of the sheet material pressing plate 12, that is, a displacement imparting member for displacing the sheet material 7 to the platen 11 side downstream of the recording area. It is possible to give a wavy shape to the sheet material 7 passing through the recording area upstream and downstream of the area.

The mounting position of the recording head 1 is set so that the sheet material 7 does not come into contact with the corrugated shape and a predetermined interval is maintained.

With the above configuration, the recording start position S (see FIG.
The sheet material 7 that has been conveyed to (see) is subjected to recording by ink droplets being applied to predetermined positions by the scanning of the recording head 1. A plurality of ejection spurs that are driven to rotate by pressing the ejection side drive roller 20 driven by a motor (not shown) and the ejection side drive roller 20 by a roller pressure contact spring 32.
The sheet material 7 is conveyed and discharged from the recording unit in the direction of arrow A in FIG.

Next, referring to FIGS. 2 and 3, the sheet material 7
The behavior before and after recording when the thickness is thin and the rigidity is low will be described. FIG. 3 is a schematic cross-sectional view showing the behavior before and after recording when the sheet material 7 is thin.

By the above-described recording operation, that is, the conveyance in the so-called recording area, the sheet material 7 loses the rigidity of the sheet pressing plate 12, becomes a valley in the concave portion 15 between the ribs 13, and becomes a peak in the rib 13 on the platen 11. A wavy shape is imparted.

Since the left and right end portions of the sheet material 7 (both end portions in the width direction orthogonal to the conveying direction) easily float to the recording head 1 side due to factors such as warpage, the protrusion 16 of the sheet material pressing plate 12 and the downstream side in the conveying direction. The protruding members (the spurs 18 in this embodiment) are arranged at the left and right ends (both ends in the width direction orthogonal to the transport direction), and
The left and right ends (only the right end in the figure) is pressed downward as shown in FIG.

Sheet material 7 that has passed through the sheet material pressing plate 12
Has a wavy shape like the sheet material 22 shown by the broken line in FIG. At this time, when the recorded image has a high density, a large amount of ink using water as a main solvent is ejected, and the ink swells to increase the size. Therefore sheet material 22
Is fixed in position by the rib 13 and the horizontal portion 17 of the sheet material pressing plate 12 which are fixed at the positions immediately before the recording area, and thus are difficult to move due to swelling. On the contrary, since the movement is not restricted between the ribs 13, the sheet material 22
The expansion due to the swelling occurs mainly between the ribs 13. Further, since the protrusion 16 is previously displaced downward, the cockling is surely generated downward, and the shape of the sheet material 7 after recording becomes the sheet material 23 shown by the solid line in FIG.

Further, since the swelling of the sheet material 7 is dispersed among the plurality of ribs 13 and the recess 15 forms a uniform cockling,
It is possible to keep each cockling low, and it does not float up to the recording head 1 side.

Then, the sheet material 22 on which a uniform cockling is formed in the recording area is conveyed by the ejection side drive roller 20. At this time, if the discharge-side drive roller 20 has a uniform cylindrical shape, the uniformly formed cockling on the upstream side will be disturbed. Therefore, in the present embodiment, the ejection side driving roller 20 is also divided and arranged on the extension line of the rib 13 on the platen 11. With such a configuration, as shown in FIG. 2, the sheet material 22 is in the state shown by the chain double-dashed line in the place without the rubber portion (sheet material conveying portion) of the ejection side drive roller 20, and Do not disturb the cockling. The division width of the delivery-side transport unit is better if it is as thin as possible within the transport range, but it is usually set to about 3 to 10 mm.

Next, the sheet material 7 will be described with reference to FIGS. 4 and 5.
The behavior before and after recording when the thickness is thick and the rigidity is high will be described. 4 and 5 are schematic cross-sectional views showing the behavior before and after recording when the sheet material 7 is thick.

As in the case of the thin sheet material, the sheet material 7 which has been fed to the nip position of the registration roller pair 10 formed by the feeding side driving roller 8 and the registration roller 9 and whose skew is corrected is When it is further conveyed, the feeding side drive roller 8
It is sandwiched between the registration rollers 9. Then, the feeding-side drive roller 8 moves downward by the thickness of the sheet material, and accordingly, the upstream side of the platen 11 also moves downward.

Since the sheet material 7 has a higher rigidity than the sheet material pressing plate 12 during the recording operation, the sheet material pressing plate 12 is bent at this time and the sheet material 7 is conveyed while being flat.

The sheet material 7 that has passed through the sheet material pressing plate 12
Is further conveyed and reaches the recording start position S. Then, the recording operation is performed, but when the sheet material 7 does not swell due to moisture like a film-type sheet material, it is conveyed flat and easily swells (for example, when the recorded image has a high density). As the sheet material swells and becomes large in size, the elongation due to the swelling of the sheet material 22 shown by the broken line in FIG. 3 mainly occurs between the ribs 13 as in the case of the thin sheet material. Since the protrusion 16 is displaced downward in advance, the cockling is surely generated downward, and the shape of the sheet material 7 after recording becomes the sheet material 23 shown by the solid line in FIG. Further, the swelling of the sheet material 7 is dispersed among the plurality of ribs 13 and a uniform cock ring is formed in the concave portion 15, so that each cock ring can be kept low and float up to the recording head 1 side. Absent.

The sheet material 7 is further conveyed and then conveyed by the ejection side drive roller 20. At this time, the discharge side drive roller 20 moves downward by the thickness of the sheet material, and accordingly, the downstream side of the platen 11 also moves downward. When the trailing edge of the sheet material 7 deviates from the nip position of the registration roller pair 10, the feeding side driving roller 8 returns upward, and the upstream side of the platen 11 also returns to its original position. On the downstream side of the platen 11, the ejection side driving roller 20 is still moving downward, and therefore, it does not return to the original position at this point.

When the printing operation further progresses and the printing of the last line of one page is completed, the operation of discharging the sheet material 7 is started. When the trailing edge of the sheet material 7 passes through the ejection side drive roller 20, the ejection side drive roller 20 returns upward, and the platen 11
The downstream side also returns to its original position.

As described above, when a thin sheet material is used, the operation is similar to that of the conventional recording apparatus, and when a thick sheet material is used, the upper and lower sides of the drive rollers 8 and 20 are adjusted according to the thickness of the sheet material. Follow the movement to record Platen 11
Moves up and down, the gap between the recording head 1 and the surface of the sheet material can always be maintained at a constant value (proper) regardless of the thickness of the sheet material used. Further, since the rollers and the sheet passing surface are always the same surface, it is possible to prevent unevenness occurring when the leading edge of the sheet material enters the rollers and contact with the recording head.

[Other Embodiments] In the above-described embodiment,
Although an example is shown in which both the upstream drive roller and the downstream drive roller are moved up and down according to the thickness of the sheet material used, the sheet material is limited to a certain thickness. For example, it may be configured such that only the drive roller on the downstream side is moved up and down, and the platen is made to follow this and moved up and down. According to this structure, with a simple structure, substantially the same effects as those of the above-described embodiment can be obtained.

Further, in the above-mentioned embodiment, the platen presses both the upstream and downstream rollers, but the upstream drive roller is held by the frame member and the drive system is also held. With the above configuration, the reliability of the rotational drive is enhanced, and the platen is rotatably attached to the frame member.

Further, in the above-mentioned embodiment, the case of the ink jet recording apparatus using one recording head has been described as an example, but the present invention is not limited to this.
For example, an inkjet recording apparatus for color recording using a plurality of recording heads for recording with different color inks, or an inkjet recording apparatus for gradation recording using a plurality of recording heads for recording with the same color but different densities, The same application can be made regardless of the number of recording heads, and the same operational effect can be achieved.

Further, as the recording means (recording head), a cartridge type in which the recording head and the ink tank are integrated, or a structure in which the recording head and the ink tank are separately provided and connected by an ink supply tube, Whatever the constitution of the recording means and the ink tank is, it can be similarly applied and the same effect can be achieved.

When the present invention is applied to an ink jet recording apparatus, it can be applied to, for example, a recording means using an electromechanical transducer such as a piezo element.
Above all, it brings an excellent effect in an ink jet recording apparatus using a recording unit of a type that ejects ink by utilizing thermal energy. This is because such a system can achieve high density recording and high definition recording.

Furthermore, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium which can be recorded by the recording apparatus. Such a recording head may have a structure that satisfies the length by combining a plurality of recording heads or a structure as one recording head integrally formed. in addition,
Even with the above-mentioned serial type, a replaceable chip that can be electrically connected to the recording head fixed to the main body of the apparatus or can be attached to the main body of the apparatus to supply ink from the main body of the apparatus. The present invention is also effective when a type of recording head or a cartridge type recording head in which an ink tank is integrally provided in the recording head itself is used.

Regarding the type or number of recording heads mounted on the carriage, for example, only one is provided corresponding to a single color ink, or a plurality of inks having different recording colors and densities are supported. And a plurality of them may be provided. That is, for example, the recording mode of the recording apparatus is not limited to a recording mode of only the mainstream color such as black, but may be a combination of a plurality of recording heads integrally formed, but a mixed color of different colors or a mixed color It is also applicable to a device with at least one of the full colors according to

In addition, as the form of the above-mentioned ink jet recording device, besides the one used as an image output terminal device of information processing equipment such as a computer, an ink jet in which a scanner other than a recording head can be mounted on a carriage. It may be a copying machine combined with an input / output device, a reader, or the like, or may be in the form of a facsimile machine having a transmitting / receiving function.

In the above-described embodiment, the ink jet recording method is exemplified as the recording method. However, the recording method is not limited to this, and other thermal transfer recording method or thermal recording method,
Further, an impact recording method such as a wire dot recording method or a recording method such as an electrophotographic method other than the impact recording method can be applied.

[0049]

As described above, according to the present invention,
Depending on the thickness of the sheet material used, the first transport roller and the second transport roller move up and down, and the platen also moves up and down following the movement of the first transport roller and the second transport roller. It is possible to always maintain a proper gap between the recording means and the sheet material regardless of the thickness of the sheet material.

Further, a first spring member for pressing the first conveying roller in the first driven roller direction and a second spring member for pressing the second conveying roller in the second driven roller direction, By adopting a configuration in which the first transport roller and the second transport roller are pressed via the platen, each transport roller and the platen can be configured to be vertically movable with a simple configuration, and each transport roller The height difference between the platen and the platen can be minimized.

Further, by arranging the platen rotatably on the frame member holding the first conveying roller, the platen can be downsized and the stability of operation can be enhanced. In addition, the structure of the drive system for driving the first transport roller, which is the main transport roller, can be configured with high accuracy.

Also, depending on the thickness of the sheet material used,
Only the second conveying roller moves up and down, and the platen also moves up and down in accordance with the movement of the second conveying roller, so that the gap between the recording means and the sheet material can always be properly maintained at low cost. It can be realized with a simple configuration.

Further, the second spring member for pressing the second conveying roller in the direction of the second driven roller presses the second conveying roller via the platen, so that the constitution is simple. The second transport roller and the platen can be configured to be vertically movable, and the height error between the second transport roller and the platen can be minimized.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a recording apparatus according to a first embodiment.

FIG. 2 is a schematic cross-sectional view of the recording apparatus according to the first embodiment.

FIG. 3 is a schematic cross-sectional view showing a behavior when a sheet material passes through a recording area.

FIG. 4 is a schematic cross-sectional view showing a behavior when a sheet material passes through a recording area.

FIG. 5 is a schematic cross-sectional view showing the behavior when the sheet material passes through the recording area.

[Explanation of symbols]

S: Recording start position 1 ... Recording head 2 ... Carriage 3 ... Guide rail 4 ... Guide roller 5 ... Support rail 6 ... Timing belt 7, 22, 23 ... Sheet material 8 ... Feed side drive roller 9 ... Registration roller 10… Registration roller pair 11… Platen 12 ... Sheet material holding plate 13… Ribs 15… Concave 16… Protrusion 17… Horizontal part 18 ... spur 19 ... Rotary axis 20… Ejection side drive roller 21 ... Spur for discharge 31, 32 ... Roller contact spring

Claims (5)

[Claims] 1. A platen for guiding and supporting the back surface of the sheet material at a position facing a recording means for recording an image on the sheet material, and a platen arranged upstream of the platen in the carrying direction for carrying the sheet material in contact with the back surface thereof. 1 conveyance roller, a first driven roller which is fixed at an upper limit position of the recording material side of the sheet material and rotates following the first conveyance roller, and a sheet material which is arranged downstream of the platen in the conveyance direction. A second driven roller that is in contact with the back surface and that is transported; and a second driven roller that is fixed at a position that is the upper limit of the recording material side of the sheet material and that rotates following the second transported roller. The first transport roller and the second transport roller are configured to be movable downward according to the thickness of the sheet material, and the platen is arranged in the thickness direction of the sheet material of the first transport roller and the second transport roller. A recording apparatus characterized in that the recording apparatus is configured to operate following a movement to. 2. A first spring member for pressing the first conveying roller in the first driven roller direction, and a second spring member for pressing the second conveying roller in the second driven roller direction.
The recording apparatus according to claim 1, wherein a spring member presses the first transport roller and the second transport roller via the platen. 3. The recording apparatus according to claim 1, wherein the platen is rotatably arranged on a frame member holding the first transport roller. 4. A platen for guiding and supporting the back surface of the sheet material at a position facing a recording means for recording an image on the sheet material; A first transport roller; a first assist roller that rotates following the first transport roller; a second transport roller that is disposed downstream of the platen in the transport direction and that contacts the back surface of the sheet material and transports the sheet material; A second assist roller which is fixed to an upper limit position of the recording material side of the sheet material and is rotated by following the second transport roller, and the second transport roller is moved downward according to the thickness of the sheet material. And a platen configured to move in accordance with the movement of the second transport roller in the thickness direction of the sheet material. 5. A second spring member for pressing the front second conveying roller in the second driven roller direction presses the second conveying roller via the platen. Item 5. The recording device according to item 4.