JPH01182074A - Recording device - Google Patents

Abstract

PURPOSE:To enable an appropriate head gap to be maintained always by providing a sheet holding member on a position where a head gap can be controlled along a sheet transport route, and permitting the sheet transport system to escape automatically from a head surface by a value corresponding to the thickness of a sheet when it is fed in. CONSTITUTION:A sheet holding member 17 provided on a position where a head gap can be controlled along a sheet transport route for instance, on a position where a sheet feed roller 4 comes into contact with a peripheral surface right under a recording head 10, is fixed to a frame. The sheet feed roller 4 is caused to come into contact with sheets by means of a roller pressure contact spring 16, and sheet transport systems 4-8 are held by the sheet holding member 17. Here, if sheets are fed into between the sheet holding member 17 and the feed roller 4 by means of the latter, the roller 4 leaves the sheet holding member 17 by sheet thickness, and an arm 15 rotates counter-clockwise by a value where the feed roller leaves with a fulcrum shaft 12 as a center. At the same time, a platen 9 rotates counter-clockwise centering around a shaft 18 and moves to a position which is away from a head surface 10A by sheet thickness. Thus, the head gap G is controlled automatically to keep an appropriate value always during recording.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a head gap regulating means that can maintain a constant gap with the head surface regardless of the thickness of the recording sheet 1 in a recording apparatus.

[Conventional technology]

Among recording devices such as printers and facsimiles, especially those using the inkjet method or the white dot method, the distance between the head surface (front surface of the recording head) and the surface (printing surface of paper, plastic thin plate, etc.) ) is required to be managed to an appropriate value.

The reason for this is that with inkjet systems, if the head gap is too small, the head surface will rub against the sheet surface, causing ink stains on the sheet or head clogging due to sheet powder, and if the head gap is too large, the ejected ink will travel a long distance. This is because problems such as printing errors become noticeable.

Further, in the wire dot method, if the head gap is different, there will be a difference in impact force, resulting in problems such as uneven printing density.

In a recording apparatus that uses limited types of sheets, since the sheet thickness is approximately constant, the head gap can be set in advance to a certain appropriate amount.

However, recent market demands require the ability to use a variety of plain papers, and the sheet thickness of plain paper varies depending on the type, ranging from thin paper of about 50 μm to 100 μm. There is a wide variation in thickness up to +1 m or thicker cardboard, and furthermore, it can reach 400 μm or more for postcards of 200 μm or more or envelopes with overlapping parts.

In order to create a structure that can use all of these plain papers,
This cannot be carried out if the positional relationship between the head and the platen remains fixed.

Conventionally, a mechanism has been developed that maintains a constant head gap by providing an eccentric lever that rotates the eccentric shaft and manually adjusting the rotational position of the eccentric lever according to the sheet thickness. It has been adopted.

[Problem that the invention seeks to solve]

However, the conventional heradgyasop adjustment structure described above has the following problems.

i) Manual operation is not convenient for the user. Especially these days, when printing on postcards and envelopes, it is often necessary to operate the eccentric lever each time, which is cumbersome to handle.

ii) Since the head gap can only be changed in steps, subtle differences occur between the print head gap and the head gap, making it impossible to sufficiently eliminate negative effects such as print deviation and uneven density.

iii) Occasionally, the eccentric lever may be operated incorrectly, resulting in printing defects each time.

iv) It is necessary to adjust the eccentric lever during assembly at the factory, increasing costs.

[Means for solving problems]

The present invention has been made to address the above-mentioned conventional problems, and an object thereof is to provide a recording device that can automatically and accurately maintain the head gap at a constant value no matter how the sheet thickness changes. shall be.

In the present invention, a sheet pressing member is provided along the general feeding route of the sheet and at a position where the head gap can be regulated, and when the sheet pressing member is fed to the sheet 1, an amount corresponding to the thickness of the sheet is The above object is achieved by a configuration in which the seam general feed system is automatically removed from the head surface.

〔Example〕

The present invention will be specifically described below with reference to the drawings.

FIG. 1 is a perspective view of a head gap regulating means of a recording apparatus according to a first embodiment of the present invention, and FIG. 2 is a left side view of FIG. 1.

In Figures 1 and 2, the gear 1-1 provided on the output shaft of the sheet feeding motor 1 meshes with the gear H of the gear 2, and the gear ■ of the gear 2 meshes with the gear IV of the gear 3. The gear IV meshes with the gear V provided on the shaft portion 5 of the sheet feed motor 1, and each time the rotation of the sheet feed motor 1 is controlled, the gear train ■,
The rotation of the sheet feed roller 4 is controlled via (1), (2), (2), and (3).

Pinch rollers 6.7 are press-contacted to the lower circumferential surface of the sheet feed roller so as to be able to separate from each other, and a paper sheet path is formed along the sheet conveyance path including the contact portion of these pinch rollers 6.7. A bread 8 is provided.

The sheet feed roller 4 rotates in the direction of arrow A (positive point), and conveys a sheet (paper, etc.) that is supplied from the direction of arrow B and is in close contact with the circumferential surface in the direction of the arrow along the circumferential surface.

A platen 9 and a recording plate 10 are arranged downstream of the sheet feeding roller 4 (upper side in FIG. 2), and a discharge roller 11 is arranged on the -L side of the platen 9. There is.

The platen 9 also serves as a sheet guide, and in the case of an ink sheet type, may also serve as a constant shield heater for drying adhered ink.

On both sides of the recording device, there are arms 15, 15 that are rotatable around the support shaft 12 of the transmission gear 3 of the sheet feeding drive system.
is pivotally supported, and a sheet conveying system including a sheet feed roller 4.5, a pinch roller 6.7 and a paper pan 8 is pivotally supported at one end of the arm 15.15. That is, this seam general feed system 4.5.6.7.8 is supported via an arm 15 so as to be rotatable about the support shaft 12 of the sheet feed transmission float 3.

Continuing from the other end of the arm 15 is a roller pressure spring 16 that urges the arm and the sheet conveyance system 4.5.6.7.8 clockwise.

A sheet pressing member 17 is provided along the sheet conveying path and at a position where it can restrict the pressure, that is, in the illustrated example, at a position where it abuts the circumferential surface of the sheet feed roller 4 directly below the recording head 10.

This sheet pressing member 17 is fixed to the frame of the recording apparatus. Therefore, normally, the sheet feed roller 4 is brought into contact with the sheet pressing member 17 by the roller pressure spring 16, and the sort 1 general feed system 4.5
．． 6.7.8 is the second
It is held at the position shown by the solid line in the figure.

The platen 9 is rotatably supported around a shaft 18 of a discharge roller 11, and is urged counterclockwise by a platen urging spring 19 installed between the platen 9 and the frame.

On the other hand, the arm (5) is formed with a stopper portion 20 against which the platen 9 hits, and depending on the rotational position of the boot J\15, the rotational position of the platen 9, that is, the recording direction.
The space between the head 10 and the head surface (front surface) 10A (\sotocamp G) can be regulated.

In the structure described above with reference to FIGS. 1 and 2, when a sheet (such as paper) is supplied and fed between the sheet pressing member 17 and the feed roller 4 by rotation of the feed roller 4, the feed roller 4 moves in a direction away from the sheet pressing member 17 by the thickness of the sheet, and the arm 15 rotates counterclockwise around the support shaft 12 by that amount.

In response, the platen 9 rotates counterclockwise about the shaft 18 and moves to a position away from the head surface 10A by the thickness of the sheet. In this way, the heradgyasop G during recording can be automatically regulated to a value appropriate for the bird, regardless of the sheet thickness.

FIG. 3 shows the left side surface corresponding to FIG. 2 of the heel gap regulating means of the recording apparatus according to the second embodiment of the present invention.

In this embodiment, the arm 15 in the embodiment shown in FIG. The shaft 5 of the sheet feed roller 4 is provided with an abutting portion +'A (for positioning the platen 9).
It has a structure in which a stopper) 24 is provided.

Further, the roller pressure contact spring 16 in this embodiment is stretched between the sheet pressing portion +A17 and the shaft 5 of the sheet 1 to the feed roller 4.

The second embodiment shown in FIG. 3 differs from the embodiment shown in FIG. 2 in the points described above, and the other parts have substantially the same structure as the embodiment shown in FIG. Therefore, in FIG. 3, the parts corresponding to those in FIG. 2 are indicated by the same reference numerals, and detailed explanation thereof will be omitted.

According to the embodiment shown in FIG. 3, when a sheet is fed between the sheet feed roller and the sheet pressing member 17, the gap corresponding to the thickness of the sheet is set, and the sheet feed roller 4 and platen 9 are placed on the spring 16. The distance between the head surface 10A and the platen 9 can be regulated to a value that maintains a constant appropriate head gap G regardless of the thickness of the head surface 10A. In addition to obtaining the same functions and effects as in the embodiment shown in FIG. 2, the structure can be simplified and lightened by eliminating the arm 15.

FIG. 4 shows a recording device according to a third embodiment of the present invention.

In this embodiment, the gear transmission means (meshing between gears ■ and gears ■) between the gear 3 and the shaft 5 of the sheet feed roller 4 in the embodiment shown in FIG. 2 is changed to a bell 1-driving means. .

That is, the gear 3 is formed with a boo IJ26 in addition to the gear ■ that meshes with the gear ■, and a pulley 2 is also formed on the shaft 5 of the feed roller.
7 is installed, and a heald (such as a belt or a timing belt) 28 is stretched between these pulleys 26 and 27. The embodiment shown in FIG. 4 differs from the embodiment shown in FIG. 2 in the above points, but has substantially the same structure in other parts. Therefore, corresponding parts are indicated by the same reference numerals, and detailed explanation thereof will be omitted.

In the embodiment shown in FIG. 4, as in the case of the embodiment shown in FIG. 2, a recording apparatus was obtained in which the head gap can be automatically regulated to a constant appropriate amount regardless of the sheet thickness.

In addition, in the embodiment shown in FIG. 3 as well, based on the same concept as described above, the gear transmission means (meshing between gears ■ and gears ■) between the gear 3 and the shaft 5 of the sheet feed roller 4 is changed to a belt drive means. It was possible to achieve similar effects.

FIG. 5 is a perspective view of the hendogyanop regulating means of a recording apparatus according to a fourth embodiment of the present invention, and FIG. 6 is a left side view with a portion of FIG. 5 removed.

This fourth embodiment includes the entire sheet conveyance system, namely, a sheet feed motor 1, a gear 2.3 for sheet feed transmission, a sheet feed roller 4, a pinch roller 6.7, and a paper pan 8.
The entire sheet conveyance system including the platen 9 is supported by a support frame 31.
．． 32 and sub-assembled (unitized) is mounted so as to be swingable about a shaft (in the illustrated example, the shaft 18 of the discharge roller 11) provided in the main body of the recording apparatus.

As shown in FIG. 5, the shaft 18 of the discharge roller 11 is supported by left and right side plates 33 and 34 of the main body of the recording apparatus.

However, a sheet pressing member 17 is fixed at a position in the sheet conveyance path directly below the head surface 10A of the recording head 10 and at a position where the head gap can be regulated. Seat 1 to feed roller pressure spring 16.16 stretched between shaft 5 of
Accordingly, the sheet feeding roller 4 moves the sheet pressing member 1
7.

When a sheet is fed and is fed between the sheet feed roller 4 and the sheet presser side 17 by the conveying force, the sheet feed roller 4 is separated from the sheet presser member 17 by the thickness of the sheet, and the sheet is moved by an amount corresponding to the thickness of the sheet. [11] Uniso I, which is constructed by assembling the entire feeding system to the support frame 31 and 32, rotates slightly counterclockwise in FIG. 6 about the shaft 18 of the discharge roller 11.

In this way, the platen 9 fixedly installed in the Uniso I rotates in the direction away from the head surface 10A toward the sheet 1 by the thickness, and the distance between the head surface 10A and the platen 9 is determined by the thickness of the sheet. The head gap G is operated to maintain a constant set value regardless of the setting value.

According to the embodiments shown in FIGS. 5 and 6, the platen 9 is moved away from the head surface 10A according to the thickness of the sheet being fed, and the distance (head gap) G between the recording surface of the sheet and the head surface 10A is increased. Since it always operates in a constant manner, it is possible to eliminate print distortion and instability of print density as in the first to third embodiments described above, and also to integrate the entire sheet conveyance system into a unit and install it in the main body of the recording apparatus. Since it can be moved all at once in a swingable manner, it is sufficient to install the transmission mechanism (gear I/lane) from the sheet feed motor 1 to the sheet feed roller 4 at two locations in the center of the recording device in the seal l-FIJ direction. Since this can be provided at the center of the sheet from sheet 1 in the width direction, it is possible to realize a lightweight and compact recording apparatus.

FIG. 7 shows a recording device according to a fifth embodiment of the present invention, and FIG. 8 is a partially removed left side view of FIG. 7.

This fifth embodiment has a seal l-+ which also includes the discharge roller 11.
1. The entire feed system, including a feed motor 1 to the saw 1, a gear 2.3 for sheet feed transmission, a sheet feed row 4, a pinch roller 6.7, a paper pan 8, a platen 9, and a discharge roller 11. The entire sheet conveyance system is supported by frames 31 and 32.
This subassembly is assembled into a subassembly unit), and this subassembly is mounted on the left and right side plates 33 and 34 of the recording apparatus main body so as to be linearly movable in the front and back direction.

The sheet flu feeding system assembly includes a shaft 5 of the sheet feeding roller 4 which passes through the support frame 31.32 and projects freely to both sides, and a rotating shaft which is implanted in each support frame 31.32 and projects outward. A prevention pin (or boss) 35.36 is formed in the side plate 33.34 of the main body of the device through a long hole 37.3 in the longitudinal direction.
8 and is attached so that it can be moved linearly in the front and rear directions.

Pinions 41, 42 are rotatably mounted on the protruding ends of the shaft 5 of the sheet feed roller 4 on both sides, and these pinions 41, 42 are connected to a groove provided integrally with the side plate 33, 34 on the main body side. It meshes with 43.44.

Therefore, it is located in the sheet conveyance path directly below the head surface 10Δ of the recording head 10 at a position where the head gap 1/1 (the distance between the head surface 10A and the printed surface of the sheet hacked up on the platen 9) can be regulated. The sheet pressing member 17 is fixed as in each of the embodiments described above.

Side plate 33, 34 on the device main body side or sheet pressing member 1
7 and the shaft 5 of the sheet feed roller 4 on the sheet conveyance system unit side is a spring 16 for urging the entire sheet+ll conveyance system forward and pressing the sheet feed roller 4 against the sheet presser side 17. .16 is strung up.

According to the head gap regulating means shown in FIGS. 7 and 8, when the sheet is generally fed and fed between the sheet feeding roller 4 and the sheet holding part +A17, the sheet feeding roller 4 is pushed backward, and the entire sheet conveying system UNISO I assembled to the support frames 31 and 32 is translated in a direction away from the head surface 10A by an amount corresponding to the sheet thickness.

In this way, the position of the platen 9 is automatically adjusted in the direction away from the head surface 10A by the sheet thickness, so that when printing, the distance between the head surface 10A and the printed surface of the sheet being fed is adjusted. can be automatically maintained at an optimal constant value regardless of sheet thickness.

According to the embodiments described above with reference to FIGS. 1 to 8, the platen 9 automatically changes the thickness of the sheet via the sheet feed roller in response to changes in the thickness of the sheet conveyed and fed into the recording section. Since the gap is removed by the thickness, the distance between the head surface 10A and the surface of the sheet (head gap) can always be maintained at a predetermined appropriate amount.

Therefore, in the ink sheet recording device, it is possible to eliminate problems such as the head surface 10Δ connecting to the sheet due to a small head gap, or the head clogging caused by sheet powder adhering to the head surface 10A, and printing even when the head gap is large. I was also able to resolve this issue.

In addition, in the wire dot recording device, the problem that the print density changes due to the difference in impact force due to the fluctuation of the head gap has been solved.

1, the head gap is automatically set to the appropriate value even when printing on postcards, envelopes, etc., eliminating any operational errors.
The result was a recording device that was difficult to handle.

In addition, the head gap is not gradual as in the past;
It can be accurately regulated according to the sheet thickness.

[Effects of the Invention] As is clear from the above description, according to the present invention, a sheet pressing member is provided along the daily sheet feeding route and at a position where the head gap can be regulated, and the sheet is fed into the sheet pressing portion +4. Since the system is configured so that the Sea 1-II feed system is automatically released from the head surface by an amount corresponding to the thickness of the sheet when the sheet is removed, the head gap can always be adjusted automatically and accurately even when the sheet thickness is different. A recording device that can maintain an appropriate amount of data can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a spacing gap regulating means of a recording apparatus according to a first embodiment of the present invention, FIG. 2 is a left side view of FIG. 1,
FIG. 3 is a left side view of the herad camp regulating means of the recording apparatus according to the second embodiment of the present invention, FIG. 4 is a left side view corresponding to FIG. 2 of the third embodiment of the present invention, and FIG. is the fourth aspect of the present invention.
FIG. 6 is a partially removed left side view of FIG. 5, and FIG. 7 is a perspective view of the spacing regulating means of the recording device according to the fifth embodiment of the present invention. 8 is a partially removed left side view of FIG. 7. 4--1--Sheet feed roller, 9-----Platen, 10-=-=--Recording head, 10 A-
------ Head surface, 16------ Spring for pressure contact with feed roller, 17 --- Sea I/holding part side, C
, =---head gap. Agent Patent Attorney Takeshi Daisho ■8

Claims (1)

[Claims] (1) A sheet holding member is provided along the sheet conveying path at a position where the head gap can be regulated, and when a sheet is fed into the sheet holding member, the sheet conveying system is moved from the head surface by an amount corresponding to the thickness of the sheet. A recording device configured to automatically release data from