JPH0516469A - Recording device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the ink adhering to the transport member from transferring to the recording medium. A discharge upper roller 4d, which is a conveying member located downstream of the recording position, can switch the contact pressure with respect to the recording medium 2, and is discharged from the recording medium 2 when the recording medium 2 is stopped during recording. The upper roller 4d is made to come into contact with a separated or weak contact pressure. [Effect] Discharge upper roller 4d that contacts the recording surface after recording.
When the recording medium 2 is stopped, the recording medium 2 is separated or is in weak contact. Therefore, it is possible to prevent the ink adhering to the discharge upper roller 4d from retransferring to the recording medium 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus that conveys a recording medium to perform recording, and more particularly to a recording apparatus that changes the contact pressure of a conveying member with respect to the recording medium.

[0002]

2. Description of the Related Art Various recording systems have been developed for use in electronic typewriters and printers. Among them, the ink jet recording method has been widely used in recent years because the apparatus can be simplified and downsized easily.

Generally, in ink jet recording, as shown in FIG. 9, a pair of conveying rollers 52a, 52 is provided upstream of the recording position of the recording head 50 in the conveying direction of the recording medium 51.
b is provided, and a pair of discharge rollers 53a and 53b is provided on the downstream side. This device ejects ink according to an image signal while moving a carriage 54 carrying a recording head 50 in a roller axis direction with respect to a recording medium 51 held by the pair of conveying rollers 52a and 52b and a pair of discharging rollers 53a and 53b. Then 1
Record lines.

During the recording (while the recording head 50 is moving forward), the recording medium 51 is stopped, and while one line recording is completed and the recording head 50 returns to the home position (during the backward movement of the recording head 50). Further, the respective roller pairs 52a, 52b, 53a, 53b are driven to convey the recording medium 51 by a predetermined amount and stop it, and the recording of the next and subsequent rows is similarly performed to obtain a desired image.

[0005]

In the ink jet recording, a pair of discharge rollers located downstream of the recording position.
53a and 53b may be gradually contaminated with ink. In particular, since the discharge upper roller 53b that contacts the recording surface contacts the recording surface immediately after recording, if the dry state of the ink discharged onto the recording medium 51 is incomplete and the water content is large, the ink is likely to transfer. .

The discharge roller pair 53a, 53b is a recording head.
While the recording medium 51 is moving forward and recording one line, the recording medium 51 that is stopped is nipped. For this reason,
When the discharge upper roller 53b is contaminated, the recording medium 51
While the sheet is being sandwiched, the ink moisture on the recording surface re-dissolves the contaminated ink on the upper roller 53b, and this contaminated ink is retransferred to the recording medium 51 to form streaks (roller traces) on the recording surface.
To get dirty.

When the discharge upper roller 53b is further contaminated, the contaminated ink is transferred to the opposite discharge lower roller 53a, and the grip force for transporting the recording medium 51 cannot be obtained and slipping occurs. There is.

As a recording medium 51 used for ink jet recording, resin thin plates (sheets for OHP, etc.) and woven fabrics have come to be used in addition to normally used paper today.
In addition to cut sheets, long recording roll sheets are also used. Since such a resin thin plate or woven cloth requires a long ink drying time, the ink is easily transferred to the discharge upper roller 53b, and the discharge roller pair 53 is used.
The a and 53b are easily contaminated. Further, in full-color recording, since the amount of ink ejected to the same portion of the recording medium 51 increases, the ink contamination is more likely to occur.

In order to prevent ink contamination of the discharge roller pair 53a, 53b, the discharge upper roller 53b is divided in the axial direction so that the discharge upper roller 53b in the recording area of the recording medium 51 does not contact the recording medium 51. In addition, a configuration is proposed in which only the ejection upper roller 53b outside the recording area contacts the recording medium 51. However, the size of the recording medium 51 is not constant, and the contact pressure balance and the like must be taken into consideration when the divided discharge upper rollers 53b are brought into and out of contact with the recording medium 51 independently of each other, which makes the apparatus complicated. Moreover, it becomes large. Further, in this case, the discharge roller pair 53a, 53
If the area where the recording medium 51 is sandwiched by b is small, a stable conveying force cannot be obtained, and as a result, a large margin is required at the end of the recording medium 51.

The present invention solves the above-mentioned problems of the prior art, and an object of the present invention is to prevent image contamination due to ink contamination of a conveying member downstream of a recording position and prevent conveyance failure to achieve high quality. An object of the present invention is to provide a recording device capable of recording.

[0011]

A typical means of the present invention for solving the above-mentioned problems is a recording means for recording on a recording medium, and an upstream side of a recording position by the recording means in a recording medium conveyance direction. A first conveying member and a second conveying member on the downstream side in the conveying direction, and switches the contact pressure of the second conveying member with respect to the recording medium, and a conveying unit for applying a conveying force to the recording medium. And a pressure switching means for that.

[0012]

In the above means, the contact pressure of the second conveying member that contacts the recording medium after recording can be changed, and the contact pressure of the second conveying member can be changed when the recording medium is stopped during recording. By weakening or separating the ink, it becomes difficult for the ink transferred to the recording medium to transfer to the second transport member, and ink contamination is reduced.

[0013]

EXAMPLE An example of the present invention to which the above means is applied will be described below. [First Embodiment] FIG. 1 is a cross-sectional explanatory view of a recording apparatus, and FIG. 2 is a structural explanatory view of a recording means. This recording device is shown in FIG.
As shown in FIG. 2, the recording mediums 2 stacked in the cassette 1 are fed one by one by the pickup roller 3, and are conveyed by the conveying means 4, and the back surface of the recording medium is supported by the platen 5. The recording means 6 is moved back and forth to record,
The recording medium 2 after recording is discharged to the discharge tray 7. As will be described later, in this recording apparatus, the discharge upper roller 4d can swing with respect to the discharge lower roller 4c, and the pressure switching means 8 can change the contact pressure between the rollers 4c and 4d.

Next, the configuration of each of the above parts will be specifically described. (Conveying Means) As shown in FIG. 1, the conveying means 4 is arranged on the upstream side of the recording position in the recording medium conveying direction, and the recording medium 2 is provided.
A pair of conveying rollers 4a and 4b for conveying the recording medium 2 to the recording position, and the recording medium 2 after recording, which is arranged on the downstream side of the recording position.
And a pair of discharge rollers 4c and 4d for discharging the sheet to the discharge tray 7. The lower transport roller 4a and the lower discharge roller 4c are connected to a transport motor 4e and can be driven and rotated.
The transport upper roller 4b and the discharge upper roller 4d are respectively the shaft 4
It is attached to arms 4h and 4i which are rotatable around f and 4g, and tensioned springs 4j and 4k locked to the arms 4h and 4i are in pressure contact with the lower conveyance roller 4a and the lower ejection roller 4c, respectively. As a result, when the carry motor 4e is driven, the recording medium 2 is carried in the direction of arrow a in FIG.

When the recording medium is conveyed, the discharge lower roller 4c rotates at a peripheral speed slightly higher than that of the lower conveyance roller 4a, and tension is applied to the recording medium 2 so that the recording medium 2 at the recording position does not loosen. ing. Even if the speed difference is set in this way, the holding force of the recording medium 2 is still high.
Since the a and 4b are set stronger than the discharge roller pair 4c and 4d, the recording medium 2 is controlled by the rotational peripheral speed of the lower conveyance roller 4a.

(Recording Means) The recording means 6 is the conveying means 4
In this apparatus, an ink image is recorded on the recording medium 2 which is conveyed by a reciprocating movement of the carriage 6a as shown in FIG. Is used. The carriage 6a is connected to an endless timing belt 6d spanned between a drive pulley 6b and a driven pulley 6c, and when a carriage motor 6e connected to the drive pulley 6b is driven in forward and reverse directions, the carriage 6a reciprocates along a guide rail 6f.

Further, four recording heads 6g integrated with an ink tank are mounted on the carriage 6a.
Color recording is performed on the recording medium 2 by ejecting four color inks of yellow, magenta, cyan, and black in accordance with the image signal during the forward movement of a.

The recording head 6g generates a fine liquid discharge port (orifice), a liquid passage, and an energy acting portion provided in a part of the liquid passage, and a droplet forming energy to act on the liquid in the acting portion. Equipped with energy generation means. As an energy generating means for generating such energy, a recording method using an electromechanical transducer such as a piezo element, irradiation of electromagnetic waves such as laser to generate heat,
A recording method using an energy generating means for ejecting liquid droplets by the action of heat generation, or a recording method using an energy generating means for heating a liquid by an electrothermal converter such as a heating element having a heating resistor to eject the liquid. There are ways. Among them, a recording head used in an inkjet recording method for ejecting a liquid by thermal energy has a high density of liquid ejection ports (orifices) for ejecting recording liquid droplets to form ejection liquid droplets. Therefore, it is possible to perform high-resolution recording. Among them, the recording head using the electrothermal converter as the energy generating means can be easily made compact, and the technological progress and the reliability improvement in the recent semiconductor field are remarkable.
You can fully utilize the advantages of C technology and micro processing technology,
This is advantageous because high-density mounting is easy and the manufacturing cost is low.

Incidentally, at the time of recording by the recording head 6g, the back surface of the recording medium 2 is supported by a platen 5, which is adhered to the recording medium 2 by electrostatic attraction, air suction, or an adhesive. It may be configured to hold the recording medium 2 so that the recording medium 2 does not float above the platen 5.

(Pressure switching means) The pressure switching means 8 is for switching the contact pressure of the discharge roller pair 4c and 4d, and as shown in FIG. 1, the eccentric cam 8b rotatable by the pressure motor 8a is at one end. Further, it is provided so as to be able to come into contact with and separate from the other end side of the arm 4i holding the discharge upper roller 4d.

Therefore, as shown by the solid line in FIG.
Is separated from the arm 4i, the discharge upper roller 4d
Is the discharging lower roller 4 by the tensile force of the tension spring 4k.
Although it is in pressure contact with c, when the cam 8b rotates and pushes down the arm 4i, the pressure contact force decreases, and when the cam 8b further rotates, the discharge upper roller 4d becomes the discharge lower roller as shown by the chain double-dashed line in FIG. Completely separate from 4c. That is, the roller pair 4c, 4d is driven by driving the pressure motor 8a.
Contact pressure is switched (including the case where the discharge upper roller 4d is separated). In this embodiment, when the recording medium 2 is conveyed, the discharge roller pairs 4c and 4d are in pressure contact with each other, and the recording medium 2 is recorded at the time of recording.
Is controlled to separate the upper discharge roller 4d from the lower discharge roller 4c.

(Control Means) Next, a control system for driving the above respective parts will be described with reference to FIG. In FIG. 3, reference numeral 9 is a control unit, which includes a CPU 9a, a ROM 9b, and an RA.
It consists of M9c. The CPU 9a is a central processing unit, which reads programs and various data from an external device 10 such as a ROM 9b and an input device, which will be described later, performs necessary calculations and determinations, and performs various controls. The ROM 9b is a read-only memory, and stores various programs for operating the CPU 9a, for example, various programs shown in the flowchart of FIG. 4, character codes, and various data necessary for dot pattern recording. The RAM 9c is a read / write memory, and a working area in which the CPU 9a temporarily stores the data in the instruction and the operation result, a buffer area in which various data input from the external device 10 and the like, a document, etc. are stored. It consists of a text area to put.

The control section 9 inputs an image signal from the external device 10 via the interface 11, and various information such as the recording density, the number of recordings, the recording size, etc. from the operating section 12. Further, the control unit 9 outputs a drive signal to a motor driver 13 for driving and controlling each motor (transport motor 4e, carriage motor 6e, pressurizing motor 8a, etc.) through the interface 11 and also controls the recording head 6b. An image signal or the like is output to the head driver 14 to drive each member.

(Printing Operation) Next, the operation of each part when printing is performed by the printing apparatus having the above-mentioned configuration will be described with reference to FIGS. 4 and 5, focusing on the movement of the discharge upper roller 4d. Incidentally, FIG. 4 is a flow chart showing the recording operation procedure, and FIGS. 5A and 5B show the discharge upper roller 4 during the recording operation.
It is explanatory drawing which shows the movement of d.

First, as shown in the flow chart of FIG. 4, the conveyance motor 4e is driven by a predetermined amount to feed the recording medium 2 to the recording position (S1), and first the recording of the first line is performed. The motor 8a is driven by a predetermined amount to rotate the eccentric cam 8b (S2), and the discharge upper roller 4d is separated from the lower roller 4c as shown in FIG. 5 (a).

In the above state, the carriage motor 6e is driven in the forward direction to move the carriage 6a forward, and ink is ejected from the recording head 6g to perform one-line recording (S3).

Next, when the next line is to be recorded (S4), the carriage motor 6e is reversely driven to move the carriage 6a back, and at the same time, the pressure motor 8a is driven by a predetermined amount to lower the discharge upper roller 4d. The rollers 4c are brought into pressure contact with each other (S5), and the carry motor 4e is driven by a predetermined amount to carry the recording medium 2 for one line (S6). That is, as shown in FIG. 5B, the eccentric cam 8b is separated from the arm 4i, and the pair of discharge rollers 4c and 4d.
Rotates while sandwiching the recording medium 2. At this time, as described above, since the rotation peripheral speed of the discharge lower roller 4c is slightly higher than the rotation peripheral speed of the conveyance lower roller 4a, the recording medium 2 is conveyed in a tensioned state at the recording position. As a result, even if the recording medium 2 that has absorbed the ink expands, the recording medium 2 does not loosen or wrinkle at the recording position.

When the recording medium 2 is conveyed by one line as described above, the process returns to step S2 and the discharge upper roller 4d is moved to the position shown in FIG.
As shown in (a), the next line recording is performed again with a space. By repeating this, a desired image is recorded on the recording medium 2.

If there is no next line recording in step S4, the process proceeds to steps S7 and S8, and the pair of discharge rollers 4c and 4d nip the recording medium 2 and rotate it to discharge it to the discharge tray 7. .

As described above, the discharge upper roller 4d which is on the downstream side of the recording position and is in contact with the recording surface is brought into contact with the recording medium 2 only during conveyance, and the recording medium 2 is stopped during the recording operation. By separating it from 2, the ink adhering to the discharging upper roller 4d is prevented from being redissolved, and the image stain due to the retransfer of the ink can be prevented. Therefore, it is possible to record a high-quality image even on a resin thin plate, a woven fabric, or the like that requires ink drying time.

In the recording structure, the recording medium 2
It is also convenient when using a roll sheet as.
That is, when a roll sheet is used as the recording medium, skew may occur due to expansion and contraction of the recording medium due to uneven image density, and ink may be ejected directly onto the platen. However, when the ejection upper roller 4d is separated from the recording medium 2 during recording as shown in FIG. 6, the recording medium 2 becomes free at the downstream side of the recording position even if part of the recording medium 2 expands or contracts. And expand and contract freely. At this time, on the upstream side of the recording position, the recording medium 2 is reliably sandwiched by the pair of conveying rollers 4a and 4d, so that the recording medium 2 is not displaced.

Therefore, even if a roll sheet is used as the recording medium 2 and the recording medium 2 expands or contracts, the discharge upper roller 4d is separated from the recording medium 2 to cause the recording medium 2 to float or wrinkle due to the expansion or contraction. Distortion and the like can be prevented, and the recording medium 2 can be conveyed without skewing to perform high-quality recording.

[Second Embodiment] In the first embodiment described above, an example in which the contact pressure of the discharge upper roller 4d with respect to the recording medium 2 is switched in two steps (pressure contact, separation) has been described. An example of switching the pressure in four steps will be described with reference to FIG. The same parts as those in the first embodiment are designated by the same reference numerals.

In the structure of the pressure switching means 15 in this embodiment, an upper discharge roller 4d is attached to one end of an arm 15b rotatable about a shaft 15a, and a tension spring is attached to the other end.
15c is attached, and the discharge upper roller 4d is urged by the spring 15c in a direction separating from the lower roller 4c.

A leaf spring 15d is attached to the upper part of the arm 15b. An eccentric cam 15e abuts on the leaf spring 15d, and the cam 15e is rotated in four steps by a pressurizing motor 15f. , P, Q, R positions. When the cam 15e pushes the leaf spring 15d, the ejection upper roller 4d comes into pressure contact with the ejection lower roller 4c through the elasticity of the leaf spring 15d. Here, the cam 15e is the leaf spring 15 at the O point.
In the state of being in contact with d, the discharge upper roller 4d is separated from the discharge lower roller 4c, and the cam 15e is at the P, Q, and R points and the leaf spring 15d.
When abutting against, the rollers 4c and 4d are in pressure contact with each other. In this case, when abutting at point Q, the strongest force is applied,
When they abut at points P and R, they are pressed with a weaker force.

A transport motor 4e is attached to the lower discharge roller 4c.
A driving force is transmitted from a discharge motor 16 other than the above through a torque limiter 17 to rotate. The torque transmitted by the torque limiter 17 is the same as that of the conveying roller pairs 4a, 4a.
b is smaller than the holding force of the recording medium 2 by b.
When the paper is held by being sandwiched by the pair of transport rollers 4a and 4b, a slip occurs in the torque limiter 17 and the lower discharge roller 4c does not rotate.

Next, the operation of each section when recording is performed by the recording apparatus having the above-mentioned configuration will be described with reference to FIGS. 7 and 8 focusing on the movement of the discharge upper roller 4d. Incidentally, FIG.
(A)-(d) is explanatory drawing which shows the movement of the discharge upper roller 4d at the time of recording operation, and FIG. 8 is a flowchart which shows a recording operation procedure.

First, the transport motor 4e and the discharge motor 16 are driven to feed the recording medium 2 to the recording position (S21). At this time, the eccentric cam 15e is in contact with the leaf spring 15d at the Q point position as shown in FIG. 7 (a). When the recording medium 2 reaches the recording position, only the conveyance motor 4e is stopped and driven (S2
2) As shown in FIG. 7B, the eccentric cam 15e rotates so as to contact the leaf spring 15d at the point P (S23), and the carriage 6a is moved forward to perform one-line recording (S24).

At this time, the discharge motor 16 is still driven, but the recording medium 2 is in a stopped state because the conveying roller pair 4a, 4b is stopped, and the tension is applied by the torque of the torque limiter 17, As a result, the extension of the recording medium 2 in the transport direction is removed. Further, at the time of this recording, the discharging upper roller 4d is in contact with the recording medium 2 with a weak contact pressure, and since this roller 4d is driven, there is no slip between the recording surface and the transfer of ink. Does not happen.

When one line recording is completed by the forward movement of the carriage 6a, the driving of the discharge motor 16 is stopped (S25), and the cam 15e is moved to the leaf spring 15d at the position of point O as shown in FIG. 7C. The carriage 6a is rotated so as to come into contact with the discharge upper roller 4d to separate it from the recording medium 2 (S26).
Is returned (S27). At this time, the recording medium 2 becomes free on the downstream side of the recording position.
Can be freely expanded and contracted to remove distortions in the width direction of the recording medium.

Next, as shown in FIG. 7 (d), the cam 15e is rotated so as to contact the leaf spring 15d at the position of the point R, the discharge upper roller 4d is weakly pressed against the recording medium 2 (S28), and the discharge is performed. The motor 16 is driven (S29). As a result, tension is applied again to the recording medium 2 once in the free state, and floating and slack are removed. At this time as well, since the contact pressure of the discharge upper roller 4d with respect to the recording medium 2 is weak, ink transfer from the roller 4d to the recording surface does not occur.

Next, as shown in FIG. 7 (a), the cam 15e rotates so as to contact the leaf spring 15d at the position of the point Q (S3
0), the recording medium 2 is brought into a transportable state. Then, it is judged whether or not there is a next line recording (S31). If there is a next line recording, the conveyance motor 4e is driven by a predetermined amount to convey the recording medium 2 for one line (S32), and the process returns to step S22. Execute the recording of the following lines. On the other hand, if there is no next line recording, the process moves to step S33 and the recording medium 2 is ejected.

Even if the pressure of the discharge roller pair 4c, 4d is switched to four stages by the pressure switching means 15 to perform the recording as described above, the conveyance failure and the recording failure are eliminated as in the first embodiment, and the high recording is performed. It is possible to record quality. [Other Examples]

Although the ink jet recording system is used as the recording means in the above-mentioned embodiment, the electrothermal converter is energized in response to a recording signal, and bubbles grow due to heating beyond the film boiling by the electrothermal converter. It is more preferable to perform the recording by discharging the ink from the discharge port. With regard to its typical configuration and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4740796. This method can be applied to both the so-called on-demand type and continuous type, but in the case of the on-demand type in particular, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal to the electrothermal converter, which corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling, thermal energy is generated in the electrothermal converter, and This is effective because film boiling is caused on the heat acting surface, and as a result, bubbles in the liquid can be formed in a one-to-one correspondence with the drive signal. Due to the growth and contraction of the bubbles, the liquid is ejected through the ejection openings to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, so that particularly excellent liquid ejection can be achieved.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. The present invention also includes configurations using US Pat. Nos. 4,558,333 and 4,459,600, which disclose configurations in which the heat acting portion is arranged in a bending region.

Further, JP-A-59-123670, which discloses a structure in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy are disclosed. Japanese Patent Laid-Open Publication No.
The effect of the present invention is effective even if the configuration is based on Japanese Patent Laid-Open No. 59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, 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 in the case of the serial type described above, it is possible to electrically connect to the apparatus main body and supply ink from the apparatus main body by mounting the recording head fixed to the carriage or the carriage. A replaceable chip type recording head or a cartridge type recording head in which an ink tank is integrally provided in the recording head itself may be used.

Further, it is preferable to add a recovery means for the recording head, a preliminary auxiliary means, etc., which are provided as a constitution of the recording apparatus of the present invention, because the effect of the present invention can be further stabilized. Specific examples thereof include capping means for the recording head, cleaning means, pressurizing or sucking means, electrothermal conversion type or other heating element or a preheating means by a combination thereof,
It is also effective to perform stable recording by performing a preliminary ejection mode in which ejection is performed separately from recording.

Regarding the type and 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, although the ink is explained as a liquid in the above-mentioned embodiments, it is an ink which solidifies at room temperature or lower and softens or liquefies at room temperature, or in the ink jet recording system. 30 inks
Generally, the temperature is controlled in the range of ℃ or more and 70 ℃ or less to control the temperature of the ink so that the viscosity of the ink is in the stable ejection range. good. In addition, it is possible to prevent the temperature rise due to thermal energy from being positively used as the energy for changing the state of the ink from the solid state to the liquid state, or to use the ink that solidifies when left standing for the purpose of preventing ink evaporation. However, in any case, heat is applied such as ink that is liquefied by application of heat energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording sheet. It is also applicable when using an ink that has the property of being liquefied for the first time by energy.

The ink in such a case is described in JP-A-54-5.
As described in JP-A-6847 or JP-A-60-71260, a form in which it is opposed to an electrothermal converter in a state where it is held as a liquid or a solid substance in a concave portion or a through hole of a porous sheet. Also good. The most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

Further, as a form of the above-mentioned ink jet recording apparatus, besides the one used as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and further a facsimile apparatus having a transmission / reception function. It may take a form or the like.

Although an example of using the ink jet recording method as the above-mentioned recording means has been described, the present invention need not be limited to the ink jet recording method, and other thermal transfer recording methods, heat sensitive recording methods, and Can also be applied to a recording method other than the impact recording method such as the wire dot recording method. Further, it is not necessary to limit to the serial recording method, and a so-called line recording method may be used.

[0055]

As described above, according to the present invention, since the contact pressure switching means of the conveying member is provided downstream of the recording means in the conveying direction of the recording medium, the ink attached to the conveying member is transferred to the recording surface. Can be prevented, and a high-quality image without image stain can be recorded. In addition, even when a recording medium having a large elasticity is used, it is possible to prevent the recording medium from floating or slacking, the conveying strain, and the like, and prevent the conveyance failure or the recording failure.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a recording apparatus according to a first embodiment of the invention.

FIG. 2 is an explanatory diagram of a configuration of recording means.

FIG. 3 is a block diagram of a control system.

FIG. 4 is a flowchart showing a recording operation procedure.

FIG. 5 is an explanatory diagram of a state of a discharge upper roller during recording.

FIG. 6 is an explanatory diagram when a roll sheet is used as a recording medium.

FIG. 7 is a diagram illustrating the recording operation of the apparatus according to the second embodiment.

FIG. 8 is a flowchart of a recording procedure according to the second embodiment.

FIG. 9 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cassette 2 ... Recording medium 3 ... Pickup roller 4 ... Conveying means 4a ... Conveying lower roller 4b ... Conveying upper roller 4c ... Discharging lower roller 4d ... Conveying upper roller 4e.
Transport motors 4f, 4g ... Shafts 4h, 4i ... Arms 4
j, 4k ... tension spring 5 ... platen 6 ... recording means 6a ... carriage 6b ... drive pulley 6c ... driven pulley 6d ... timing belt 6e ... carriage motor 6f ... guide rail, 6g ... recording head 7 ... ejection tray 8 ... pressure switching means 8a ... Pressurizing motor 8b ... Eccentric cam 9 ... Control unit 9a ... CPU 9b ... ROM 9c ...
RAM 10 ... External device 11 ... Interface 12 ... Operation unit 13 ... Motor driver 14 ... Head driver
15 ... Pressure switching means 15a ... Shaft 15b ... Arm 15c ... Spring 15d Leaf spring 15e ... Eccentric cam 15f ... Pressurizing motor 16 ... Discharge motor 17 ... Torque limiter

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masatoshi Imai             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation (72) Inventor Setsu Uchida             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation (72) Inventor Atsushi Munakata             Kyano, 3-30-2 Shimomaruko, Ota-ku, Tokyo             Within the corporation

Claims (6)

[Claims] 1. A recording means for performing recording on a recording medium, a first conveying member on the upstream side in the conveying direction of the recording medium with respect to the recording position by the recording means, and a second conveying member on the downstream side in the conveying direction. A recording apparatus, comprising: a conveying unit that applies a conveying force to the recording medium; and a pressure switching unit that switches a contact pressure of the second conveying member with respect to the recording medium. 2. The first transport member and the second transport member,
The roller of the second conveying member, which is composed of a pair of rollers opposed to each other and is in contact with the recording surface of the recording medium when the recording medium is stopped, has a weaker contact force with respect to the recording medium than during conveyance, or The recording apparatus according to claim 1, wherein the recording apparatus is configured to be separated from the medium. 3. The recording apparatus according to claim 2, wherein the roller of the second conveying member on the side in contact with the recording surface of the recording medium is a driven roller. 4. The recording apparatus according to claim 1, wherein the recording unit is an inkjet recording system that performs recording by ejecting ink according to a signal. 5. The ink jet recording method in which the recording means energizes an electrothermal converter according to a signal and ejects ink by utilizing thermal energy of the electrothermal converter for recording. The recording device described. 6. The recording means energizes an electrothermal converter in response to a signal, and ink is ejected from an ejection port due to growth of bubbles caused by heating beyond film boiling by the electrothermal converter for recording. The recording apparatus according to claim 5, which is an inkjet recording method.