JPH10291682A - Image recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly prevent the running inertia of a recording sheet from causing runaway and control effectively and finely feeding quantity, by providing a spring means which movably supports a discharging roller in the discharging direction of the recording sheet, and energizes the discharging roller onto the opposite side to the discharging direction. SOLUTION: When the recording speed is high, or a motor stops suddenly, a recording sheet 10 runs speedily in the discharging direction due to its inertia force. In this case, a discharging roller 13 moves in the discharging direction of the recording sheet 10, a rocking arm 25 rocks as shown by an arrow (d), a tension spring 27 extends, and therefore, the running inertia energy of the recording sheet 10 is stored in the tension spring 27 (b). Immediately after that, the rocking arm 25 returns speedily and smoothly by the energy stored in the tension spring 27, and the discharging roller 13 and a clutch arm 23 returns to their original state. The recording sheet 10 returns to the condition controlled by a sending roller 18 (a).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus, and more particularly, to a recording head which causes ink or toner to fly or emit light on a recording sheet fed to a recording section by a feed roller in accordance with image data. The present invention relates to an image recording apparatus that records an image by irradiation and discharges the image by a discharge roller.

[0002]

2. Description of the Related Art Conventionally, in the above-described image recording apparatus, as shown in FIG. 5, a feed roller 41 is driven by a drive motor 42 via a feed-side gear interlocking mechanism 43. The discharge roller 48 is driven in conjunction with the feed roller 41 via a clutch mechanism 44 in which a rubber roller 46 at the tip of the clutch arm 45 is brought into contact with the clutch arm 45 and a discharge-side gear interlocking mechanism 47 interlocked with the rubber roller 46. The recording sheet 50 is configured to be pinched and discharged by a spur roller 49 and a discharge roller 48 that are rotatably supported and urged toward the discharge roller 48 to move. The drive motor 42 is step-driven, and the recording sheet 5 has a length corresponding to the rotation amount of the motor.
0 is sent. Reference numeral 51 denotes a driven roller which is urged so as to be in pressure contact with the feed roller 41, and the recording sheet 50 is sandwiched between the driven roller 41 and
The recording sheet 50 is configured to be fed without causing slippage.

According to such a configuration, the discharge roller 48
When the recording sheet 50 stopped in the middle of discharging is strongly pulled to the downstream side, as shown in FIG.
Is driven to rotate in the discharge rotation direction, and the clutch arm 45 swings in the direction to separate the rubber roller 46 from the feed roller 41 via the discharge-side gear interlocking mechanism 47, thereby the clutch mechanism 44 is opened, and recording is performed. Sheet 5
0 can be pulled out without difficulty.
And the speed difference between the discharge rollers 48 can be absorbed.

[0004]

However, in the above configuration, when the end portion of the recording sheet 50 passes through the feed roller 41, the recording sheet 50 is fed only by the discharge roller 48. As a result, the discharge roller 48 is driven by the travel of the recording sheet 50, and the clutch mechanism 44 is released in the same manner as when the recording sheet 50 is forcibly pulled out as shown in FIG. 5B. . Therefore, the recording sheet 50 runs away due to its traveling inertia, and the feed amount cannot be finely controlled. That is, the recording sheet 50 moves more than the motor control amount by the step drive. As a result, if an attempt is made to print on a portion near the end portion of the recording sheet 50, that is, a portion outside the guaranteed recording range set, for example, in the range of about 20 mm from the end of the recording sheet 50, an image recording error (e.g. There is a problem in that a dropout occurs.

In order to prevent the recording sheet 50 from running out of control, a discharge roller 48 and a discharge-side gear interlocking mechanism 47 are provided.
It is also known that a suitable friction is provided on the gear of the wheel to convert the energy of runaway into heat energy.However, since the value of friction is unstable, it is difficult to reduce the amount of runaway, so actually Has a problem that a sufficient effect cannot be exhibited.

In view of the above problems, the present invention can effectively suppress runaway and excessive movement of a recording sheet at the time of recording on the end portion of the recording sheet, and can improve quality at the end portion of the recording sheet. It is an object of the present invention to provide an image recording apparatus capable of forming a good image.

[0007]

According to a first aspect of the present invention, there is provided an image recording apparatus, comprising: a feed roller which is driven to rotate by a drive motor to feed a recording sheet to a recording section; and a clutch mechanism which comes into contact with and separates from the feed roller. A discharge roller that is driven to rotate in synchronization with the rotation of the feed roller via the clutch mechanism and the gear interlocking mechanism to discharge a recording sheet, and a unit that supports at least the discharge roller so as to be movable in a recording sheet discharge direction. And spring means for urging the discharge roller in the direction opposite to the discharge direction.

According to this configuration, when the recording sheet is fed only by the discharge roller and the clutch mechanism is released due to its running inertia and the recording sheet runs away, at least the discharge roller is moved by the spring means in the discharge direction of the recording sheet. In response to the movement, the energy is stored in the spring means as the movement proceeds, and the stored energy causes the discharge roller to quickly and smoothly return to the original state. Can reliably prevent runaway due to
Therefore, an image having a predetermined quality can be formed even when an attempt is made to print on an area outside the guaranteed recording area set at the end of the print sheet.

According to a second aspect of the present invention, there is provided an image recording apparatus which is driven to rotate by a driving motor to feed a recording sheet to a recording section, and which is rotated and driven in synchronization with the rotation of the feed roller via a gear interlocking mechanism to perform recording. A discharge roller for discharging the sheet, means for swingably supporting the discharge roller around a rotation axis of an interlocking gear meshing with a gear fixed to the discharge roller, and a discharge roller opposite to the rotation direction of the interlocking gear And a spring means for urging and oscillating in the direction.

According to this, when the discharge roller is driven in conjunction with the feed roller via the gear interlocking mechanism, the discharge roller is swung against the spring means, and the recording sheet is fed only by the discharge roller. If the discharge roller tries to rotate extra by the backlash of the gear interlocking mechanism due to the inertia of the recording sheet in the state of being moved, the discharge roller is returned by the amount of backlash by swinging in the opposite direction by the spring means. In addition, excessive feeding due to the inertia of the recording sheet due to running inertia can be reliably prevented, and the feeding amount can be effectively and finely controlled.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An ink jet printer according to an embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, which shows a schematic structure of a main mechanism of the ink jet printer 1, reference numeral 2 denotes a carriage on which a recording head 3 is mounted.
A plurality of ink tanks 4 (A, B) for supplying a predetermined color of ink to the printer are detachably mounted. The carriage 2 is supported by a lower guide means 5 and an upper guide means 6 so as to be able to reciprocate along a predetermined movement path parallel to the width direction of the recording sheet 10, and a drive pulley 8 and an idle pulley (see FIG. (Not shown) and a timing belt 9 wound between both pulleys. The lower guide means 5 supports the carriage 2 movably only in the direction of the movement path, and the upper guide means 6 supports the carriage 2 movably in the direction of the movement path of the carriage 2 and in the vertical direction.

Reference numeral 11 denotes a platen disposed immediately below the recording head unit 3, which constitutes a recording unit for recording an image on the recording sheet 10 passing between the platen 11 and the recording head unit 3. I have. The platen 11 also serves as a guide plate for guiding the recording sheet 10 toward the recording section. Reference numerals 13 and 14 denote a discharge roller and a spur roller which are disposed on the lower side in the transport direction of the recording sheet 10 from the recording unit and discharge the recording sheet 10.

At the time of recording, the carriage 2 is moved by a stepping drive motor 7, a drive pulley 8, an idle pulley (not shown), and a timing belt 9 to form a recording sheet 10.
The main scanning is performed in the width direction, and an image for one or a plurality of lines is recorded by the recording head unit 3 mounted on the carriage 2. Each time printing by one main scan is completed, the recording sheet 1
0 is sent in the vertical direction and is sub-scanned. The image is recorded on the recording sheet 10 in this manner, and the recording sheet 10 that has passed through the recording section is discharged by the discharge roller 13 and the spur roller 14 pressed against the discharge roller 13.

In FIG. 2, reference numeral 17 denotes a paper feed tray for stacking and supporting the recording sheets 10, and the recording sheets 10 are fed one by one by a paper feed roller (not shown). Reference numeral 18 denotes a feed roller which is disposed on the upper side of the recording unit and conveys the recording sheet 10 to the recording unit. The feed roller 18 is driven by a driving motor 20 composed of a stepping motor via a feed-side gear interlocking mechanism 21. Is transmitted at a predetermined pitch with high precision in relation to the main scanning. Reference numeral 19 denotes a driven roller which is biased so as to sandwich the recording sheet 10 with the feed roller 18, and is configured to feed the recording sheet 10 accurately without causing slippage.

Reference numeral 22 denotes a clutch mechanism which makes the rubber roller 24 at the tip of a swingably supported clutch arm 23 come into contact with the feed roller 18 by its own weight or a light spring force, and rotates so that the rubber roller 24 can be brought into contact with and separated from the feed roller 18. It is configured to transmit force.

Ejection roller 1 disposed on the lower side of the recording section
3 is attached to one end of a swing lever 25 whose middle portion is swingably supported by a pivot 26, and the other end of the swing lever 25 is connected to a tension spring 27 as an urging means. The recording sheet 10 is urged toward the discharge side by a predetermined urging force. Thus, the discharge roller 13 is movably supported in the discharge direction of the recording sheet 10 and is urged to the opposite side to the discharge direction. Numeral 28 denotes a positioning part for abutting the other end of the rocking lever 25 to position the discharge roller 13 at a predetermined position, and numeral 29 denotes a restricting part for restricting the rocking limit.

The rubber roller 24 and the discharge roller 13 are linked by a discharge-side gear link mechanism 30. The discharge gear interlocking mechanism 30 includes a gear 31 fixed to the rubber roller 24.
And a gear 32 meshed with the gear 31 and rotatable around the pivot axis of the clutch arm 23, and a gear 3 meshed with the gear 32 and rotatable around the axis of the pivot 26.
3 and a gear 34 meshed with the gear 33 and fixed to the discharge roller 13.

In the above configuration, at the time of image recording operation, the recording sheet 10 fed from the paper feed tray 17 is sandwiched between the feed roller 18 and the driven roller 19 and synchronized with the image recording by the recording head unit 3 with high feeding accuracy. Sent.
When the leading end of the recording sheet 10 reaches the discharge roller 13,
The discharge roller 13 is interlocked with the feed roller 18 so as to have substantially the same feed amount, and the speed difference is absorbed by the clutch mechanism 22 so that the recording sheet 10 is fed by the feed roller 18 and the discharge roller 13. And discharged from its tip. When the end of the recording sheet 10 comes off the feed roller 18, the recording position of the recording head unit 3 at that time is about 20 mm from the end of the recording sheet 10, and the recording assurance area from that position to the end. Then, the sheet is discharged and conveyed only by the discharge roller 13.

Here, when the recording speed is high or when the motor is suddenly stopped, the recording sheet 10 runs strongly in the discharge direction due to its inertia force, and as shown in FIG. Conversely, the traveling of the seat 10 is rotationally driven in the direction of the arrow a, whereby the clutch arm 23 is oscillated and urged as shown by the arrow b via the discharge side gear interlocking mechanism 30, and the clutch mechanism 22 is released. As a result, the feed control by the feed roller 18 is released, and the recording sheet 10 runs out of control due to the inertial running as indicated by the arrow c, and the recording sheet 10 tends to run out. However, in the present embodiment, when the recording sheet 10 tries to travel with the inertial force, the discharge roller 13 moves in the discharging direction of the recording sheet 10 due to the inertial force, and the swing arm 25 swings as shown by the arrow d. When the tension spring 27 is extended, the traveling inertia energy of the recording sheet 10 is stored in the tension spring 27. Immediately thereafter, the swing arm 25 is quickly and smoothly returned to the state shown in FIG. 2A by the energy stored in the tension spring 27, and the discharge roller 13 and the clutch arm 23 return to the original state. Recording sheet 10
Returns to the state controlled by the feed roller 18. Thus, runaway due to the inertia of the recording sheet 10 can be reliably prevented, and the feed amount can be effectively and finely controlled. Therefore, recording may be performed on a part of the recording sheet 10 that is not guaranteed for recording set at the end of the recording sheet 10. In this case, an image having a predetermined quality can be formed. In the present embodiment, at the time of printing after the recording sheet 10 has come off the driven roller 19, it is necessary to perform printing after returning by the tension spring 27, so that the printing speed is made slower than usual.

In the case where the recording sheet 10 being discharged is pulled out by the discharge roller 13 due to the image recording being stopped halfway, the recording sheet 10 being discharged is continuously pulled strongly to the downstream side. The discharge roller 13 is driven to rotate in the discharge rotation direction, and the clutch arm 23 swings in the direction to separate the rubber roller 24 from the feed roller 18 via the discharge-side gear interlocking mechanism 30 to release the clutch mechanism 22. , The recording sheet 10 can be pulled out without difficulty.

Next, a second embodiment of the present invention will be described with reference to FIG. In the above-described embodiment, the discharge roller 13 is attached to one end of a swing arm 25 pivotally supporting an intermediate portion so as to be movably supported, and the other end of the swing arm 25 is urged by a tension spring 27. In this embodiment, the discharge roller 13, the discharge-side gear interlocking mechanism 30 for driving the discharge roller 13, and the clutch mechanism 22 are disposed on a movable block 35 which is movable.
Compression spring 36 biasing toward the side opposite to the zero discharge direction.
Is arranged.

Also in this embodiment, the recording sheet 10
When the user attempts to run with inertial force, the discharge roller 13 is moved by the inertia force together with the movable block 35 into the recording sheet 1.
When the compression spring 36 is compressed by moving in the discharge direction of 0, the traveling inertia energy of the recording sheet 10 is stored in the compression spring 36, and immediately after that, the movable block 35 is restored by the energy stored in the compression spring 36. Is quickly and smoothly returned to the state, and the recording sheet 10 is returned to the state where the feed is controlled by the feed roller 18, whereby the same operation and effect as in the above-described embodiment can be obtained.

Next, a third embodiment of the present invention will be described with reference to FIG. In the first embodiment, the feed roller 18 and the discharge roller 13 are linked via the clutch mechanism 22. However, in this embodiment, the clutch mechanism 22 is omitted, and the discharge-side gear interlocking mechanism 30 is omitted. First gear 3
1 is rotatable about a fixed shaft center, and is disposed so as to mesh with a fixed gear 21a on the last-stage feed roller 18 of the feed-side gear interlocking mechanism 21. The other end of the swing arm 25 is urged by a compression spring 38 in a direction opposite to the discharge direction.

In this embodiment, during the normal image recording operation, while the discharge roller 13 is rotationally driven via the discharge side gear interlocking mechanism 30 in synchronization with the rotation of the feed roller 18, FIG. 2), the swing arm 25 is swung in the direction of arrow e by the rotational force of the gear 33 against the urging force of the compression spring 38. afterwards,
When the recording sheet 10 attempts to run with inertial force, the discharge roller 13 is driven to rotate by the inertial force, and
As shown by the solid line in (b), the gear 34 fixed to the discharge roller 13 rotates with respect to the gear 33 as shown by the backlash minute arrow f, and the recording sheet 10 is likely to be excessively fed. However, at the same time, the urging force of the compression spring 38 causes the swing arm 25 to swing in the direction opposite to the arrow e, and the gear 3
4 is immediately returned by the amount of backlash as indicated by the imaginary arrow g, and immediately thereafter, the discharge roller 13 is returned to a state in which the discharge roller 13 is driven by the discharge-side gear interlocking mechanism 30, whereby excessive feed of the backlash is performed. Is prevented, and the compression spring 38 is compressed again to return to the original state. Thus, according to the present embodiment, even when the clutch is directly connected without the interposition of the clutch mechanism 22, it is possible to prevent the excessive feed of the backlash of the gears and to finely control the feed amount. An image having a predetermined quality can be formed even in a case where recording is to be performed on a part outside the guaranteed recording area set at the end of the recording medium 10.

In each of the above-described embodiments, as shown by phantom lines in FIGS. 2, 3 and 4, a cylindrical guide 39 is arranged by being fitted over the outer periphery of the tension spring 27 and the compression springs 36 and 38. In addition, it is possible to prevent the spring means from swaying and meandering, to ensure proper operation, and to prevent vibration.

[0027]

According to the first aspect of the present invention, as is apparent from the above description, the discharge roller which is driven to rotate in conjunction with the rotation of the feed roller via the clutch mechanism and the gear interlocking mechanism is recorded. Since the spring means is provided to movably support the sheet in the sheet discharging direction and to urge the sheet in the direction opposite to the discharging direction, the discharging roller is driven by the traveling inertia in a state where the recording sheet is fed only by the discharging roller, When the clutch mechanism is released and the recording sheet runs out of control, at least the discharge roller moves in the recording sheet discharge direction against the urging means, and is stored as energy in the spring means with the movement. After that, the output roller is returned to the original state promptly and smoothly by the stored energy, ensuring runaway due to the inertia of the recording sheet. This prevents the feed amount from being effectively and finely controlled, so that even if an attempt is made to print on a portion of the end of the recording sheet that is not guaranteed for recording, an image with a predetermined quality is formed. can do.

According to the image recording apparatus of the second aspect,
A spring means for swingably supporting the discharge roller about a rotation axis of an interlocking gear meshing with a gear fixed to the discharge roller, and urging the discharge roller in a direction opposite to the rotation direction of the interlocking gear. Since the discharge roller is driven in conjunction with the feed roller via a gear interlocking mechanism, the discharge roller is swung against the spring means, and the recording sheet is fed only by the discharge roller. If the discharge roller tries to rotate extra by the backlash of the gear interlock mechanism due to the inertia of the recording sheet, the discharge roller will swing back in the opposite direction by the spring means, and the feed amount will be returned by the backlash and the feed amount will be increased. Excessive feeding is prevented, and excessive feeding due to the running inertia of the recording sheet is reliably prevented, so that the feeding amount can be effectively and finely controlled, and the same effect is exerted.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of a main mechanism of an embodiment of an image recording apparatus of the present invention.

2A and 2B show a schematic configuration of a main part of the embodiment, wherein FIG. 2A is a front view, and FIG. 2B is a partial front view of an operation state.

FIG. 3 is a front view showing a schematic configuration of a main part of an image recording apparatus according to a second embodiment of the present invention.

FIG. 4 is a front view showing a schematic configuration of a main part in a third embodiment of the image recording apparatus of the present invention.

5A and 5B show a schematic configuration of a main part of a conventional image recording apparatus, wherein FIG. 5A is a front view, and FIG. 5B is a partial front view of an operation state.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink jet printer (image recording device) 13 Discharge roller 18 Feed roller 20 Drive motor 22 Clutch mechanism 25 Swing arm 27 Tension spring 30 Discharge-side gear interlock mechanism 35 Movable block 36 Compression spring 38 Compression spring

Claims (2)

[Claims] A feed roller which is rotated by a drive motor and feeds a recording sheet to a recording section; a clutch mechanism which comes into contact with and separates from the feed roller; and a rotation of the feed roller via the clutch mechanism and a gear interlocking mechanism. A discharge roller that is driven to rotate in conjunction with the discharge roller to discharge the recording sheet; a means for supporting at least the discharge roller in a direction in which the recording sheet is discharged; and a spring means for urging the discharge roller in a direction opposite to the discharge direction. An image recording apparatus comprising: 2. A feed roller which is rotated by a drive motor and feeds a recording sheet to a recording section, and a discharge roller which is driven to rotate in synchronization with rotation of the feed roller via a gear interlocking mechanism and discharges the recording sheet. Means for supporting the discharge roller so as to be capable of swinging about a rotation axis of an interlocking gear meshing with a gear fixed to the discharge roller, and urging the discharge roller in a direction opposite to the rotation direction of the interlocking gear. An image recording apparatus comprising: a spring means.