JPS62167158A - Recording device - Google Patents

Abstract

PURPOSE:To search the head portion of a sheet at pinpoint accuracy easily with a single sensor, by controlling an rotating amount of a rotating body for transporting a sheet after its extreme end is detected. CONSTITUTION:When the front end of a cut sheet 5 reaches a sheet sensor 22, it is sensed to stop a rotating body 18 and a paper feed roller 7 and then only the rotating body 18 is rotated in a reverse direction so that the cut sheet 5 is returned to the side of a cut sheet feeder 1. Since the rear end of the cut sheet 5 is still being frictionally held by the paper feed roller 7, the loop 15 of the cut sheet 5 is formed. The front end of the cut sheet is depressed to the engaging portion with a 1st pinch roller, that is, a depressing member 19A at all times by the force of the cut sheet waist produced by the loop and then it is regulated. The rotating body 18 comprising transportation rollers is rotated a prescribed number of rotation in the forward direction A so that the front end of the cut sheet 5 passes through the pinch rollers 19A, 19B and a recording head 16 and it is set at a prescribed head setting position.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to sheet conveyance control means in a recording apparatus equipped with a cut sheet feeder (automatic paper feeder).

[Prior art]

As a recording device such as a printer or facsimile, it is equipped with a general feed mechanism consisting of a pressing member such as a pinch roller placed on the circumference of a rotating body such as a sheet conveyance roller, and a cut sheet feeder is installed on the sheet entrance side. The format is used. The pressing members can be arranged at two or three locations.

In this case, the sheet that is fed from the sheet inlet side (upstream side) and collides with the pressure contact part of the upstream pressing member (pinch roller) is printed by rotating the rotating body (transport roller) by a predetermined angle in the forward direction. Set to starting position.

It is necessary to set this sheet accurately and automatically regardless of whether manual feeding mode or automatic paper feeding mode is selected. It is necessary to make this determination and ensure the accuracy of sheet cue control.

However, in conventional recording devices of this type, the sheet sensor is placed on the cut sheet feeder side or upstream of the pressing member of the recording device, which makes it difficult to control sheet cueing. The problem is that dedicated sensors are required for controlling the loop amount of the sheet feeder and for determining the paper feeding mode, resulting in a complicated structure and increased cost.

〔the purpose〕

It is an object of the present invention to overcome these problems of the prior art, achieve high cueing accuracy, and use a single sensor to determine paper feeding mode, cue control, and obtain an appropriate loop amount when a cut sheet feeder is installed. An object of the present invention is to provide a recording device that can be controlled.

[Overview] The present invention provides a recording device that is equipped with a sheet conveyance mechanism in which a first pressing member and a second pressing member are brought into contact with a rotating body, and is equipped with a cut sheet feeder that automatically feeds sheets. The above object is achieved by disposing a sheet sensor between the first pressing member and the second pressing member to control sheet conveyance.

〔Example〕

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

FIG. 1 shows a sectional view of essential parts of a recording apparatus according to an embodiment of the present invention.

In FIG. 1, a cut sheet feeder 1 that automatically feeds paper is removably equipped with an upper paper feed cassette 2 and a lower paper feed cassette 3, and each paper feed power center 2.3 has cut sheets 4, 5, is loaded. Further, the cut sheet 4 comes into frictional contact with the first paper feed roller 6, and the cut sheet 4
is in frictional contact with the second paper feed roller ruff, and the drive shaft 8 of the first paper feed roller 6 or the drive shaft 9 of the second paper feed roller ruff is rotated by a driving means (not shown), and the cut sheet 4 or 5 is transferred to the recording device. Sent to the 17th side.

The lower side of the rotating body 18 for sheet conveyance, such as a sheet conveyance roller or a platen roller, provided in the recording device 17 is
The carriage 20 on which the recording head 16 is mounted is pressed by pressing members 19A and 19B such as pinch rollers.
A guide plate 21 is fixed to the rotating body 18 side.

Therefore, the two pressing members 19A on the circumferential surface of the rotating body 18
, 19B, a sheet sensor 22 is disposed between the sheets 4 and 5 to detect the presence or absence of the sheet or the passage of the leading edge of the sheet in order to control the conveyance of the sheet. This seat sensor 22
can be composed of, for example, a photosensor.

Above the rotating body 18 (on the downstream side) is a guide plate 24.2.
5 are provided, and the sheet guided by these guide plates is driven upward and discharged through between paper discharge rollers 26 and 27.

A pail roller 23 is disposed on the circumferential surface of the rotary body 18 on the downstream side of the recording head 16 so as to be able to press away from it.

Further, a sheet insertion opening 28 is provided in front of the cut sheet feeder 1 for manually feeding sheets.

The operation of the recording device described above during paper feeding is shown in Figure 2 (
This will be explained with reference to A) to FIG. 2(C).

In the automatic paper feed mode, the cut sheet 5 is fed out from the lower paper feed cassette 3 by driving the second paper feed roller 7 in the direction of the arrow, and the leading edge of the cut sheet 5 is fed out from the lower paper feed cassette 3 as shown in FIG. 2(A). It comes into contact with the meshing portion of a rotating body 18 such as a 1M feed roller and a pressing member (first pressing member 9) 19A such as a pinch roller. In this case, since the rotary body 18 for conveying the sheet is rotating in the six directions of the arrows (forward direction), the leading end of the cut sheet 5 passes through the engagement part with the pressing member (pinch roller) 19A, and No. 2 pressing member 19A.

The position of the sheet sensor 22 between 19B and 19B is reached.

'J2 [m (B) When the sheet sensor 22 is reached, it is detected and the rotating body 18 and paper feed roller 7 are stopped, and then only the rotating body 18 is moved in the opposite direction (direction B).
, and return the cut sheet 5 to the cut sheet feeder 1 side. The amount of reversal at this time is set to be larger than the amount fed previously.

On the other hand, since the rear end of the cut sheet 5 is still frictionally held by the paper feed roller, the rotating body 18 and the first pressing member 1
A loop 15 of the cut sheet 5 as shown in FIG. 2(C) is formed on the upstream side of the engaging portion with the cut sheet 9A.

Therefore, an appropriate amount of loops 15 are formed by feeding the cut sheet 5 by an appropriate amount at the beginning, and the force (repulsion force) of the cut sheet 5 caused by the loops causes the leading end of the cut sheet to always be moved by the first pinch roller. That is, it is regulated by being pressed against the meshing portion with the first pressing member 19A.

From this state, move the rotating body 18 consisting of a conveying roller in the forward direction A.
The tip of the canted sheet 5 is rotated by a predetermined amount to pass through the pinch rollers 19A, 19B and the recording head 16, and is centered at a predetermined cue position.

The predetermined cue position is accurately controlled by rotating the sheet sensor 22 by a predetermined amount after the leading edge of the sheet has passed.

The case where the cut sheet 5 is automatically fed has been explained above.
The same operation is performed when automatically feeding cut sheets 4 from the upper paper feed cassette 2.

In the manual feed mode, the cut sheet is inserted from the sheet insertion opening 28.

In this case, the paper feed rollers 6.7 are stopped, only the conveyance roller 18 is rotated in the forward direction, and the leading edge of the cut sheet passes through the pinch roller 19A and reaches the sheet sensor 22.

Therefore, the sheet sensor 22 detects that the tip of the cut sheet has arrived and determines that it is the manual feed mode, and by rotating the pulse motor a predetermined number of steps, the conveying roller is rotated by a predetermined amount, and the cut sheet is transferred to the pinch roller 19A.
, 19B, the recording medium is conveyed to the recording start position while being guided by pressure, and the setting is completed. In this manner, by controlling the amount of rotation of the conveyance roller 18 from the sheet sensor +22, it is possible to locate the beginning of the canted sheet with high precision.

First, the conveying roller 18 is rotated by a predetermined amount, and if the sheet sensor 22 does not detect any paper, it is determined that the mode is the cut sheet feeder mode, and the cut sheet feeder side is driven.

FIG. 3 is a block diagram of a recording apparatus according to an embodiment of the present invention. 50 is a control unit, and 51 is a driver that drives the recording head, motor, and the like. 52 is a recording head, 53 is a line feed motor that drives the rotating body 18, 54 is a carriage motor that drives the carriage 20,
55 is a cut sheet feeder motor that drives the paper feed roller.

The present invention is applicable not only to the case where the rotary body 18 for sheet conveyance is constituted by the illustrated platen roll, but also to the case where the rotary body 18 is constituted by a general rotary body.

Further, the present invention provides first and second pressing members 19A, 1
Not only when 9B is configured with the illustrated pinch roller,
It is also applicable in the same way to a configuration using an elastic member such as a leaf spring or other pressing means.

〔effect〕

As is clear from the above description, according to the present invention, the sheet sensor for controlling sheet conveyance is disposed between the first and second pressing members on the sheet conveying circumferential surface. By controlling the amount of rotation of the sheet transport rotor after detecting the leading edge, it is possible to easily and accurately position the sheet with just one sensor. can.

In addition, since each pressing member is generally placed below the sheet conveyance roller (roller), the sheet sensor (photo sensor) can be placed in a position where it is less affected by external light, and detection accuracy can also be improved. .

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of the main parts of a recording apparatus according to an embodiment of the present invention, and FIGS. 2(A) to 2(C) are explanatory diagrams showing the sheet feeding operation of the recording apparatus of FIG. 1. , FIG. 3 is a block diagram of a control system of the recording apparatus of FIG. 1. 1.--Cut sheet feeder, 4.5-1111-Cut sheet, 15--Loop, 17.
---Recording device, 18---Rotating body (sheet conveyance roller), 19A. 19B--First and second pressing members (pinch rollers), 22--Sheet sensor. Figure 2

Claims (3)

[Claims] (1) In a recording device that is equipped with a sheet conveyance mechanism in which a first pressing member and a second pressing member are in contact with a rotating body, and is equipped with a cut sheet feeder that automatically feeds sheets, a sheet sensor is installed. A recording apparatus characterized in that the recording apparatus is arranged between the first pressing member and the second pressing member to control sheet conveyance. (2) The recording apparatus according to claim 1, wherein after the sheet sensor detects the leading edge of the sheet, the rotating body is reversed to form an appropriate loop at the leading edge of the sheet. . (3) The recording apparatus according to claim 1 or 2, wherein after the rotating body rotates by a predetermined amount, it is determined whether the mode is manual feeding mode or automatic paper feeding mode.