JP2744440B2 - Recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus, and more particularly to a so-called serial type in which a recording head is moved in a processing direction with respect to a transport direction of a recording medium, and recording is performed in the course of the movement. (Hereinafter referred to as a serial printer).

[Prior Art] Conventionally, in a serial printer, a recording head is fixed to a movable portion (hereinafter, referred to as a carriage), and therefore, paper, an OHP sheet, or another recording medium (hereinafter, also referred to as recording paper or simply paper). The distance between the recording head and the recording element forming surface of the recording head is mainly determined by the arrangement of the guide shaft of the carriage.

However, there are various thicknesses of the recording medium for recording. For example, there are thick papers such as postcards and envelopes in addition to so-called recording paper. In view of this, there has been proposed a configuration in which a member for supporting the guide shaft so as to be able to be displaced is provided, and the amount of the deviation is adjustable by manual operation so that the guide shaft can be adapted to various thicknesses.

[Problems to be Solved by the Invention] However, in such a configuration, not only does the operator have to make adjustments, but also in the case of poor adjustment, the distance between the head and the recording medium becomes inappropriate. Naturally, it is impossible to obtain a high-quality recorded image, and in severe cases, a recording error, damage to a recording head, or a jam is liable to occur. This is particularly remarkable in a serial printer in which it is desirable that the interval is strictly controlled, for example, a serial printer using a recording head of an ink jet system.

It is an object of the present invention to enable accurate interval adjustment without requiring an operation by an operator, and to solve the above problems.

[Means for Solving the Problems] For this purpose, according to the present invention, a head mounting member for mounting a recording head, a shaft member that instructs the head mounting member to be rotatable and extends in a predetermined direction, A transport roller for transporting a recording medium toward a recording area by the recording head, a pinch roller for pressing the recording medium against the transport roller, and displacing the pinch roller according to a thickness of the recording medium. A pinch roller stay that supports the head mounting member in order to support the recording head in a position corresponding to the thickness of the recording medium in accordance with the displacement, and the recording medium that has passed the pinch roller. Projecting from the head mounting member side to the recording surface more than the thickness of the recording medium relative to the position of the recording head or the head mounting member with respect to the recording surface, A projection member for avoiding contact between the recording head or the head mounting member and the recording surface after the recording medium has passed through the pinch roller.

[Operation] According to the present invention, the recording head can take an optimum position in accordance with the conveyance of the recording medium, so that the recording quality does not deteriorate and adjustment by the operator is not required.

Further, the recording head or the head mounting member protrudes from the head mounting member side to the recording surface more than the position of the recording head or the head mounting member with respect to the recording surface of the recording medium that has passed the pinch roller, and performs recording after the recording medium passes the pinch roller. Since the recording medium has the protruding member for avoiding contact between the head or the head mounting member and the recording surface, it is possible to avoid direct contact between the recording surface of the recording medium that has passed the pinch roller and the recording head or the head mounting member.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an external perspective view of an ink jet recording apparatus according to one embodiment of the present invention, and FIG. 2 is a sectional view of a main part of the apparatus shown in FIG. FIG. 3 is a partially enlarged view of the paper feed mechanism in FIG.

In these figures, reference numeral 61 denotes a pressure plate, which is stacked to supply recording paper to the ink jet recording apparatus. Reference numeral 62 denotes a pressure plate spring attached to the rear surface of the pressure plate 61, and the pressure plate 61 is urged upward by the pressure plate spring 62. Reference numeral 63 denotes a paper width regulating plate which is slidably provided on the pressure plate 61 and regulates the position of the recording paper loaded on the pressure plate 61 in accordance with the width of the recording paper. A separation roller 65 separates the recording sheets stacked on the pressure plate 61 one by one, and is fixed to a separation roller shaft 651. Reference numeral 652 denotes a circular pressing roller, one provided on each side of the separation roller 65, and attached so as to freely rotate with respect to the separation roller shaft 651. A pressing plate pressing down cam 661 is fixed to one end of the separation roller shaft 651, and a pressing plate pressing down cam 6
A separation roller gear 662 is rotatably fitted adjacent to 61. A spring clutch 663 is provided between the pressure plate pressing down cam 661 and the separation roller gear 662. When the lock ring 664 provided around the spring clutch 663 is locked by the lock claw 665, the rotational force is not transmitted (off). When the lock pawl 665 is disengaged from the lock ring 664 and the lock ring 664 is free, the rotational force is transmitted (ON). Here, the lock claw 665 is brought into contact with the above-described lock ring by dynamic contact with a protrusion of the carriage 5 described later.
664 is at the position where the engagement is released.

A cam receiving portion 611 is formed on the pressure plate 61 at a position where the cam receiving portion 611 engages with the pressure plate pressing down cam 661. Thus, when the pressure plate 61 is pressed down by the pressure plate pressing cam 661, the recording sheet is separated from the separation roller 65 and the pressing roller 652. The recording paper is pressed down at 62 and pressed against the separation roller 65.

On the downstream side of the pressure plate 61 in the sheet feeding direction, a separation pad 66 for frictionally separating the recording sheets one by one is provided.
The separation pad 66 is urged toward the separation roller 65 and the holding roller 652 by a pad spring 67. The holding roller 652 has a circular shape in a cross section perpendicular to the roller shaft 651, the separating roller 65 has a substantially semicircular arc shape in the same cross section, and the radius of the separating roller 65 is larger than the radius of the holding roller 652. Make it slightly larger. As a result, the separation pad 66 is pressed against the separation roller 65 in the arc region of the separation roller 65, and is pressed against the pressing roller 652 in the other range.

Here, the diameter of the separation roller 65 is relatively small, about 20 to 30 mm. As a result, the angle α from the contact point of the pressure plate 61 with the separation roller 65 to the contact point of the separation pad 66 with the separation roller 65 increases, as shown in FIG. Can be made large relative to the pressure plate 61, and the separation performance is not impaired even if the separation pad pressure by the pad spring 67 is small. Whereas a normal separation roller diameter (about 40 mm) required a separation pad pressure of about 300 g, a small diameter (20 to 30 mm) enables separation without problems even at around 50 g. Therefore, the back tension received from the pressing roller 652 and the separation pad 66 when the recording paper is being fed by the paper feed roller 7 is reduced, and stable paper feeding is possible.

Further, a change in the feed amount generated when the trailing edge of the recording paper comes off from the press roller 652 and the separation pad 66 is also suppressed.

Reference numeral 7 denotes a recording sheet fed by the above-described sheet feeding mechanism.
And a paper feed roller provided on a transport path for transporting the print head to a print position facing the print head.
A pinch roller 81 is provided so as to sandwich the recording paper. The pinch roller 81 is rotatably supported at both ends on a pinch roller stay 8 urged by a pinch roller spring 82. The pinch roller stay 8 is attached so as to be rotatable about a stay fulcrum 83. Reference numeral 9 denotes a paper guide which guides the recording paper fed from the paper feeding mechanism to a position between the paper feed roller 7 and the pinch roller 81. Reference numeral 10 denotes a paper pressing plate which presses the floating of the recording paper from the pinch roller 81.

The paper feed roller 7 is driven by a motor (not shown),
At this time, the transmission of the driving force is performed in one stage by a gear or the like, and the reduction ratio is such that the paper is fed by one rotation of the motor for one line of recording. As a result, white streaks that occur at the joints of the recording lines in the recorded image due to paper feed,
The eccentric components of the motor itself and the motor gear, which cause image deterioration such as overlapping, are canceled. Further, since the speed from the drive motor to the paper feed roller 7 is reduced by one step, and the driving force is transmitted by the minimum transmission element, no extra error component is included.

Reference numeral 11 denotes a heating plate having a heater on the back surface, and promotes fixing of ink on recording paper in cooperation with a power supply unit described later. There is no practical problem if the temperature of the hot plate 11 is in the range of 40 ° C to 90 ° C. Reference numeral 12 denotes a paper discharge roller, and a paper discharge pinch roller 13 is provided to face the paper discharge roller. The paper ejection pinch roller 13 does not have a pinch roller 13 and is formed in a vehicle shape, and the recording surface side of the recording paper is pressed with a dot to prevent the recording surface from being rubbed or the like when an incompletely fixed ink recording surface occurs. Also, the feed speed of the paper discharge roller 12 is made several percent faster than the feed speed of the paper feed roller 7 to apply tension to the recording paper,
The recording paper is kept in close contact with the hot plate 11 and the flat surface of the recording paper at the recording position is maintained.

The heating plate 11 is located downstream of the recording element of the recording head 51 in the recording paper conveyance path so that heat from the heating plate 11 is not directly applied to the recording element portion of the recording head 51. Further, a gap is provided between the paper guide 9 and the heating plate 11, and detection by a paper width sensor constituted by a reflection type photo sensor provided on the carriage 5 is performed at the gap portion, whereby reflection by the guide or the like is performed. Prevent false detection.

Reference numeral 15 denotes a guide shaft, the carriage 5 is movably engaged on the shaft 15 to move left and right, and the carriage 5 has a rotation fulcrum coaxial with the motor 16 to which a driving force is transmitted from the motor 16 via a belt 19. A pulley 171 is disposed on the tension plate 17, and a constant tension is applied to the belt 19 by a tension spring 172.

The carriage 5 is rotatably mounted around the guide shaft 15, and the pressing portion 54 of the carriage 5 presses the surface of the pinch roller stay 8 by the weight of the carriage 5. The pressing portion 54 forms a slider and slides on the pinch roller stay 8 as the carriage 5 moves. The material of the pressing portion 54 is formed of a resin having particularly high slidability such as Teflon. Further, the carriage 5 has a protrusion 55 near the connection with the recording head 51, and the protrusion 55
Although it protrudes forward by about 0.3 to 0.5 mm from the ejection surface 51, it does not contact the paper holding plate 10 in a normal state.

FIG. 4 shows a recording system unit including the recording head 51 and the carriage 5.

In the present embodiment, the recording head 51 forms ink droplets for recording using thermal energy, and includes ejection openings arranged in the paper feeding direction and ejection energy generating elements corresponding to each of the ejection openings. It has a discharge unit 518. The position of the recording head 51 with respect to the carriage 5 is determined by fitting the projection of the recording head 51 with the hole of the carriage 5. A fixed lever 52 is provided on the carriage 5 at a fulcrum 52.
Attached so that it can rotate around 5. The fixed lever 52 has elastic portions 521 and 523 that generate a pressing force when the recording head 51 is fixed to the carriage 5. The fixed lever 52 engages the fixed lever hook portion of the lever 52 with the hook portion of the carriage 5. Then, the fixing lever 52 is locked, and the recording head 51 is fixed to the carriage 5. Reference numeral 5-a denotes a fixed base that serves as a reference for positioning the recording head 51 in the side direction.

The carriage 5 has a paper width sensor 11 for detecting the width and presence / absence of the recording medium when the carriage 5 moves.
43 are provided. This paper width sensor is mounted so that the detection position is located near the discharge orifice located at the most downstream position of the discharge orifice of the recording head 51 in the paper feed direction.
Further, a protruding portion 57 for releasing the engagement of the lock claw 665 of the sheet feeding mechanism described above is provided near a portion of the carriage 5 that engages on the guide shaft 15, and is provided outside the recording area in the carriage movement path. The engagement is released by contacting the lock claw 665 at a predetermined position. Further, the carriage 5 has a cap positioning pin, and is used for positioning when the carriage 5 retreats to the position of the recovery device during non-recording and caps the recording element surface of the recording head 51.

Reference numeral 150 denotes an ejection recovery device that performs capping of the ejection surface of the recording head 51 and suction of ink, and is disposed on one side of the moving path of the carriage 5 outside the recording area. In the ejection recovery device 150, a cap 156 caps the ejection surface of the recording head 51, and the cap 156 is a positioning lever 15 that engages with a positioning pin of the carriage 5.
7 is provided. Reference numeral 18 denotes an ink cartridge for storing ink to be supplied to the recording head 51. The ink cartridge 18 includes a waste liquid collecting unit for storing waste ink sucked by capping.

Reference numeral 79 denotes a power supply unit, which is fixed on the bottom plate 1002 so that a heat radiation plate of the power supply unit is located directly below the paper discharge tray.

 The operation in the configuration described above will be described below.

First, the sheet feeding operation will be described with reference to FIG. 5. When the recording is not performed, the carriage 5 is capped by the cap 156 of the recovery device 150, and is in a recording standby state. When receiving the recording data from the host computer or the data transfer device, the carriage 5 starts moving to release the lock claw 665 located on the opposite side to the moving path recovery device 150.
When the lock claw 665 is released, the lock ring 664 is released, and the rotation of the separation roller gear 662 can be transmitted to the separation roller shaft 65 and the pressure plate pressing down cam 661, and the separation roller 65 and the pressure plate pressing down cam 661 are rotated by driving the motor. start. After the drive of the motor is started, the carriage 5 moves to a position where it does not prevent the lock claw 665 from returning to a position where it can return due to its own elasticity (a position where it engages with the lock ring 664), and waits. When the pressure plate press-down cam 661 starts rotating, the pressure plate 61 moves upward by the urging force of the pressure plate spring 62 and is pressed against the separation roller 65, and the recording paper is fed to the position of the separation pad 66 with the rotation of the separation roller 65. It is.
Here, the recording paper is wrung and the separation roller 65 and the separation pad
By 66, only one sheet is fed to the position of the paper feed roller 7 and the pinch roller 81 within one rotation of the separation roller 651.
When the hook of the lock ring 664 reaches the position of the lock hook 665 again, the rotation of the lock ring 665 is stopped, and the rotation of the separation roller 65 stops.

Normally, the paper feeding operation is completed by one rotation of the separation roller 65. However, if the length up to the paper feed roller 7 becomes longer than the circumference of the separation roller 65 due to the configuration of the apparatus, the separation roller 65 is rotated a plurality of times. Will be. In this case, the carriage 5 is waiting at the position where the engagement of the lock claw 665 is released until the last rotation starts. In the paper feeding operation, when the leading edge of the recording paper is detected by a paper edge sensor located between the paper feeding roller 7 and the separation roller 65, the recording paper is fed from the position by a predetermined amount, and then the paper feeding roller 7 is moved. Is stopped, and the sheet feeding and the cueing of the recording sheet are completed.

Thereafter, the carriage 5 returns to the recovery device 150 side. At this time, the paper width and the presence or absence of paper are detected by a paper width sensor provided on the carriage 5. If the paper feeding operation is performed normally, the width of the recording paper, that is, the size of the recording paper is detected, and the recording is not performed outside the recording paper. If no recording paper is detected, it is determined that paper feeding is defective, and an error occurs and the operation stops.

The engagement release operation of the lock claw 665 at the time of paper feeding by the carriage 5 is performed at least twice so that such a paper feeding failure does not occur.

After the paper feeding is completed as described above, the carriage 5 reciprocates in the width direction of the recording paper, and accompanying this, the paper feed roller 7 performs recording while feeding the paper for each line of the recording head 51. Do. At this time, the gap between the recording head 51 and the recording paper surface is determined by the pressing portion 54 of the carriage 5 that slides on the pinch roller stay 8. That is, since the pinch roller 81 is provided on the pinch roller stay 8, when the recording paper enters between the paper feed roller 7 and the pinch roller 81, the pinch roller stay 8 moves toward the carriage 5 correspondingly. Therefore, even if the thickness of the recording paper changes, the pinch roller stay 8 moves accordingly, so that a constant gap is always maintained.

The recorded recording paper is sent between a paper discharge roller 12 and a paper discharge pinch roller 13 through a hot plate 11 for fixing ink.
After the trailing edge of the recording paper is displaced between the paper feed roller 7 and the pinch roller 81, the recording paper is fed by the paper discharge roller 12 and the paper discharge pinch roller 13, and after the last line of recording is performed, the paper
Sent to 10. The recording paper fed into the paper discharge tray 1010 is subjected to ink fixing and the like by heat generated from a heat radiating plate of a power supply unit 79 immediately below the paper discharge tray 1010.

When the recording paper is a thick paper such as an envelope or a postcard, when the recording paper comes off from the space between the paper feed roller 7 and the pinch roller 81, the carriage protruding portion 55 causes the paper pressing plate 10 protruding toward the carriage due to the paper thickness. Since the upper surface slides, the ejection surface of the recording head 51 does not need to directly rub the recording paper surface.

With the above operation, recording of one sheet of recording paper is completed, and thereafter, the same operation is repeated.

As described above, according to the present embodiment, the carriage is guided on the pinch roller stay to which one of the transport rollers is attached, so that the optimal head position is always maintained for recording media of various paper thicknesses. Is obtained, so that good quality recording can always be compensated. With such a structure, the gap between the head and the paper feed roller can be reduced, and the non-recordable area at the lower end of the recording medium can be reduced.

Further, by providing a portion protruding from the front surface of the recording head in the vicinity of the recording head, the recording head is formed on the recording paper even if the carriage returns to the front side after making the recording paper particularly thick such as an envelope or a postcard. Good recording without contamination is possible without rubbing. Further, since the protruding portion can be easily provided by changing the shape of the existing component, there is no increase in cost due to the protruding component.

Note that the present invention is not limited to the above-described embodiments, but can adopt various configurations.

For example, FIG. 6 shows that a gap assurance member is provided on the paper holding plate 10 at a clearance of about 0.2 to 0.5 mm with respect to the forefront of the carriage 5 on the paper feed side, contrary to the provision of the protrusion on the carriage 5. 10-a is provided.

Even in this case, the same effect as the above-described configuration can be obtained. After the thick paper such as an envelope or a postcard is separated from the paper feed roller 7 and the pinch roller 81, the gap assurance member 10-a provided on the paper holding plate 10 is provided. Since the front surface of the carriage 5 slides upward, the front surface of the recording head 51 does not have to rub the surface of the recording paper.

In FIG. 7, a projection 51-a corresponding to the projection 55 of the carriage 5 is provided directly on the front surface of the recording head 51.

Accordingly, a more accurate gap assurance can be obtained since there is no accumulation of errors between parts, as compared with the configuration in which the protrusion 55 is provided on the carriage 5 and the configuration in which the gap assurance member 10-a is provided in the paper holding plate 10. It becomes possible.

Further, in the case of the above-described embodiment, the pinch roller stay is made to follow the printhead and the carriage by its own weight.
An elastic body such as a spring may be used to follow the forced pinch roller stay.

In addition, the position of the head can be controlled by changing the shape of a part of the pinch roller stay. For example, both ends (outside the recording range) of the pinch roller stay can be deformed in a direction in which the distance between the head and the paper increases, thereby preventing the head from coming into contact with the recording paper due to curling of both ends of the recording paper.

In addition, by selecting the guide shaft of the carriage and the position guided by the guide plate, a different relationship can be provided between the thickness of the recording paper and the moving amount of the head. That is, when the thickness of the recording paper is large, the head may move more than the thickness of the recording paper, and the danger of the head contacting an envelope or the like having an irregular surface may be reduced.

Further, in the above example, the carriage is supported so as to be movable from the recording area, but the carriage may be supported so as to be movable on the carriage.

Further, the present invention can be effectively applied not only to a printer using an ink jet recording head as described above, but also to various printers, as long as a serial printer in which the interval between a recording element and a recording medium is to be managed. Of course.

[Effects of the Invention] As described above, according to the present invention, accurate adjustment of the distance between the recording head and the recording medium is performed without requiring an operation by an operator, and the recording quality is reduced and the recording head is not changed. Damage and other inconveniences can be prevented.

Further, the recording head or the head mounting member protrudes from the head mounting member side to the recording surface more than the position of the recording head or the head mounting member with respect to the recording surface of the recording medium that has passed the pinch roller, and performs recording after the recording medium passes the pinch roller. Since the recording medium has the protruding member for avoiding contact between the head or the head mounting member and the recording surface, it is possible to avoid direct contact between the recording surface of the recording medium that has passed the pinch roller and the recording head or the head mounting member.

[Brief description of the drawings]

1 is a perspective view of an ink jet recording apparatus according to one embodiment of the present invention, FIG. 2 is a cross-sectional view of the apparatus shown in FIG. 1, FIG. 3 is a partially enlarged view of a paper feed mechanism in FIG. FIG. 4 is a perspective view showing a detailed configuration example of a recording system unit including a recording head and a carriage, FIG. 5 is an explanatory diagram for explaining a sheet feeding operation, and FIGS. It is a figure showing a modification. 5 Carriage 7 Paper feed roller 8 Pinch roller stay 9 Paper guide 10 Paper holding plate 10-a Gap assurance member 15 Guide shaft 51 Recording head, 51-a ... projection, 54 ... pressing part, 55 ... projection part.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinya Matsui 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yoji Ara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Junichi Asano 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (56) References JP-A-57-49587 (JP, A) JP-A-58-59878 (JP) , A) JP-A-63-42883 (JP, A)

Claims (2)

(57) [Claims] 1. A head mounting member for mounting a recording head, a shaft member instructing the head mounting member to be rotatable, and a shaft member extending in a predetermined direction; and a recording medium facing a recording area of the recording head. A transport roller for transporting, a pinch roller for pressing the recording medium against the transport roller, and supporting the pinch roller so as to be displaceable according to the thickness of the recording medium, and A pinch roller stay that supports the head mounting member to set a recording head at a position corresponding to the thickness of the recording medium; and the recording head or the head mounting member with respect to a recording surface of the recording medium that has passed the pinch roller. Above the position corresponding to the thickness of the recording medium and projecting from the head mounting member side to the recording surface, after the recording medium has passed the pinch roller. Recording apparatus characterized by having a protruding member to avoid contact with the definitive said recording head or said head mounting member and the recording surface. 2. The recording apparatus according to claim 1, wherein the recording head has a form in which a droplet of a recording liquid is formed using thermal energy to form an image.