JPH05543A - Recording device - Google Patents

Abstract

(57) [Summary] [Structure] The sheet pressing members 7a and 7b are provided on the upstream side and the downstream side of the recording position, and when the carriage 8 moves, the sheet pressing members 7a and 7b are attached by the pressing members 9a and 9b attached to the lower end of the carriage. Turns to record sheet 2
Is pressed against the platen 5. Further, the sheet pressing members 7a and 7b are attached to the rotating shafts 13 and 15 through the elongated holes so as to be movable up and down by a minute amount. [Effect] Even if the heights of the platen 5 and the rotary shafts 13 and 15 are deviated, the sheet pressing members 7a and 7b move within the range of the long holes to absorb the deviance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording apparatus for recording on a recording medium, and more particularly to a recording apparatus having a pressing member for preventing the recording medium from floating.

[0002]

2. Description of the Related Art Conventionally, in a recording apparatus which performs serial recording, one line of recording is performed by scanning a carriage, and then a required amount of recording paper is conveyed to perform recording of the next and subsequent lines. Examples of such recording devices include inkjet printers and impact printers, and these recording devices try to improve the recording quality by making the distance between the recording paper and the recording head as close as possible. However, when the recording paper floats or sags at the recording position, the recording paper and the recording head may rub against each other, and the recording paper may become dirty.

Therefore, as shown in FIG. 6, a pressing member 50,
The recording paper 56 in the passage area of the recording head 55 is pressed against the platen 57 by the weight of the carriage 52 via the pressing members 53 and 54, thereby preventing the recording paper 56 from floating.
58a to 58d are conveying rollers, the pressing member 50 is centered on the conveying roller 58b, and the pressing member 51 is the conveying roller.
It is swingably engaged with 58d as a center.

[0004]

However, in the structure shown in FIG. 6, the pressing member 5 has a variation due to manufacturing variations.
When the height of the platen 57 is deviated from the height of the transport roller, which is the center of swing of 0, 51, the thickness of the recording paper 56 is large, or the one pressing member 51 and the recording paper 56 are in close contact with each other. If there is a gap between the other pressing member 50 and the recording paper 56, the pressing member will rotate and oscillate more than the set amount. It may come into contact with the head 55 and damage the head 55. On the contrary, as shown in FIG. 8, a gap g may be formed just below the pressing members 59 and 60, and the distance between the recording head 55 and the recording paper 56 may become wider than the set amount.

The present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to prevent the recording medium from floating and to always maintain a stable distance between the recording medium and the recording means. The purpose is to provide a recording device that can do this.

[0006]

A typical means of the present invention for solving the above-mentioned problems is a recording means for recording on a recording medium conveyed onto a platen, and the recording means is mounted to the recording means. A carriage that can reciprocate in a recording area with respect to the medium, and a pressing member that is disposed on at least one of the upstream side and the downstream side in the recording medium transport direction with respect to the recording area and that is displaced to press the recording medium against the platen. A pressing member for respectively displacing the pressing member by the movement of the carriage, wherein the pressing member is attached so as to be rotatable about a rotation axis and movable with respect to the rotation axis. It becomes a feature.

Further, the pressing member is configured to be urged in a direction opposite to the pressing direction of the pressing member between the rotating shaft and the pressing position of the pressing member.

[0008]

In the above means, when the carriage moves during recording and the pressing member presses the pressing member, the pressing member moves so that the entire area of the pressing member comes into contact with the recording medium. Contact is prevented and the gap between the recording means and the recording medium is reliably maintained at a predetermined amount.

Even if the pressing member and the recording medium are not in complete contact with each other, the tip of the pressing member is prevented from floating, and the tip of the member does not come into contact with the recording means.

[0010]

【Example】

[First Embodiment] Next, a recording apparatus according to an embodiment of the present invention in which the above means is applied to an ink jet recording system will be described. This recording device, as shown in FIG.
Recording sheets 1 which are recording media laminated inside are fed one by one by a pick-up roller 3, which is conveyed by a sheet conveying means 4, and recording is performed on a recording sheet 2 whose back surface is supported by a platen 5. The recording head 6 as a means is driven to perform recording, and the sheet pressing member 7 suppresses the floating of the recording sheet 2 during the recording.

When the carriage 8 moves during recording, the sheet pressing member 7 is pressed against the recording sheet 2 by the pressing member 9 attached to the carriage 8,
When the carriage 8 returns to the home position, the recording sheet 2
Configured to be isolated from. Next, the configuration of each of the above parts will be specifically described.

(Sheet Conveying Means) The sheet conveying means 4 is, as shown in FIG. 2, a conveying roller 4a and a pinch roller 4b for conveying the recording sheet 2 to the recording area, and the recording sheet 2 after recording to the discharge tray 10. It is composed of a discharge roller 4c for discharging and a pinch roller 4d. Conveyor roller 4a
The discharge roller 4c and the discharge roller 4c are connected to a transport motor (not shown) and can be driven and rotated. The pinch rollers 4b and 4d are attached to one end of an arm 4f rotatable about a shaft 4e and the other end of the arm 4f. A tension spring 4g locked to the side end is configured to come into pressure contact with the transport roller 4a and the discharge roller 4c. As a result, when the transport motor is driven, the recording sheet 2 is transported in the direction of arrow a in FIG.

A driving force is transmitted to the discharge roller 4c through a slip clutch (not shown) so as to rotate at a rotational peripheral speed several% faster than the rotational peripheral speed of the conveying roller 4a, and the recording sheet 2 is conveyed. A moderate tension is applied to the.

(Carriage) The carriage 8 is slidably and rotatably attached to the slide rail 8a shown in FIG. 2, and the carriage 8 is moved along the slide rail 8a by the carriage motor and drive transmission system (not shown). Is configured to reciprocate in the width direction. A home position sensor for detecting the carriage 8 is provided at the home position position of the carriage 8, and when the carriage 8 is at the home position position, it is outside the recording area of the recording sheet 2. (Position in FIG. 2).

(Recording Means) The recording means records an ink image on the recording sheet 2 conveyed by the conveying means 4.
In this apparatus, an inkjet recording method is used as a recording unit, the inkjet head 6 is mounted on the carriage 8, the recording head 6 ejects ink according to a recording signal in synchronization with the movement of the carriage 8, and the ink is recorded on the recording sheet 2. Record the image.

The recording head 6 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 the energy generating means for generating such energy, a recording method using an electromechanical transducer such as a piezo element, an energy generating means for irradiating electromagnetic waves such as a laser to generate heat, and ejecting droplets by the action of the heat generation And a recording method using an energy generating means for heating the liquid by an electrothermal converter such as a heating element having a heating resistor to eject the liquid. Among them, a recording head used in an inkjet recording method for ejecting a liquid by heat 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 record at high resolution. Among them, the recording head using the electrothermal converter as the energy generating means can easily be made compact, and has the advantages of the IC technology and the microfabrication technology, which have been remarkably improved in the technology and the reliability in the recent semiconductor field. This is advantageous because it can be used in two parts, high-density mounting is easy, and the manufacturing cost is low.

(Sheet pressing member) Sheet pressing member 7
Is for preventing the recording sheet 2 from floating during recording, and the upstream side sheet pressing member is located on the upstream side in the conveying direction of the recording sheet 2 with reference to the recording area of the recording sheet 2 to be recorded by the movement of the recording head 6. 7a are provided, and downstream sheet pressing members 7b are provided on the downstream side in the transport direction of the recording sheet 2.

The upstream side sheet pressing member 7a is shown in FIG.
As shown in FIG. 3, an arm portion 7a2 is formed by bending from both ends of a pressing portion 7a1 having a length equal to or larger than the width of the recording sheet 2, and the arm portion 7a2 is rotatably supported by a shaft 13.

Here, the shaft-supporting engagement hole 11 of the arm portion 7a2 is in the shape of a circular elongated hole which is long in the vertical direction, and when the arm portion 7a2 is rotated, the arm portion 7a2 is slightly moved with respect to the shaft 13. The amount can be moved up and down. Further, a plate spring 14 is provided below the platen 5, and an end portion of the plate spring 14 contacts an end surface of the arm portion 7a2 to urge the pressing portion 7a1 in the direction of arrow b in FIG. The arm portion 7a2 is configured to come into contact with the shaft 4e serving as a stopper by the force.
When the arm portion 7a2 is in contact with the shaft 4e, the pressing portion 7a1 is separated from the platen 5 as shown in FIG.

Further, an inclined portion 7a3 is formed at one end portion in the longitudinal direction of the pressing portion 7a1 so that a pressing roller 9a, which will be described later, attached to the lower portion of the carriage 8 can easily ride on the pressing portion 7a1. ..

On the other hand, similarly to the upstream sheet pressing member 7a, the downstream sheet pressing member 7b is formed by bending arm portions 7b2 at both ends of a pressing portion 7b1 having a length equal to or larger than the width of the recording sheet 2. 7b2 and the shaft 15 are engaged as shown in FIG. That is, the flat portions 15a, 15 of the shaft 15
Since b and the flat portions 12a and 12b of the arm engaging hole 12 that is elongated in the vertical direction are fitted, the arm 7b2 can move in the vertical direction by a small amount with respect to the shaft 15. Moreover, the rotation of the shaft 15 can be transmitted to the arm portion 7b2.

A torsion coil spring 16 is attached to one end of the shaft 15, and the downstream sheet pressing member 7b is constantly urged by the spring 16 in the direction of arrow c in FIG. Further, a gear 17 is attached to the shaft 15, and the gear 17 meshes with a gear 18. A pin 18a is provided on the side surface of the gear 18, and a lever 19 provided on the outside of the gear 18 engages with the pin 18a to stop the gear 17 and the sheet pressing member 7b at a predetermined position. Then, as shown in FIG. 3, the pressing portion 7b1 is separated from the platen 5.

An inclined portion 7b3 is formed at one end portion in the longitudinal direction of the pressing portion 7b1 so that a pressing roller 9b, which will be described later, attached to the lower portion of the carriage 8 can easily ride on the pressing portion 7b1.

(Pressing Member) The pressing member 9 presses the sheet pressing members 7a and 7b against the platen 5,
In this embodiment, the upstream side pressing roller 9 is provided at the lower end of the carriage 8.
a and the downstream side pressing roller 9b are provided. When the carriage 8 moves in the direction of arrow d in FIG. 2, the pressing rollers 9a and 9b move the roller 9a onto the upstream side sheet pressing portion 7a1.
Further, the rollers 9b ride on the downstream side sheet pressing portions 7b1. At this time, the sheet pressing portions 7a and 7b are urged by the weight of the carriage 8 to cause the leaf spring 14 and the torsion coil spring 16
The recording sheet 2 rotates against the bias of the recording sheet 2 as shown in FIG.
Are pressed against the platen 5 by the sheet pressing portions 7a1 and 7b1.

(Biasing Point for Sheet Pressing Member) The upward biasing point P by the leaf spring 14 for the upstream side sheet pressing member 7a is between the shaft 13 and the pressing position by the pressing member 9a as shown in FIG. Is configured to be located at. Similarly, the upward biasing point Q of the torsion coil spring 16 with respect to the downstream side sheet pressing member 7b is determined by the shaft 15 and the pressing member 9b.
It is configured so as to be located between the pressing position by the.

(Rotating axis of the platen 5 and the sheet pressing member
In the recording apparatus having the above-described configuration, when the carriage 8 moves with respect to the recording sheet 2 conveyed onto the platen 5, as described above, the pressing roller 9 moves.
a and 9b ride on the pressing portions 7a1 and 7b1,
The a1 and 7b1 press the recording sheet 2 against the platen 5 to prevent it from floating.

At this time, when the platen 5 and the rotational axes 13, 15 of the sheet pressing members 7a, 7b are misaligned with respect to the set height relationship due to variations in assembly or the like, the sheet pressing members 7a, 7b Since 7b can move up and down within the range of the long holes 11 and 12, the sheet pressing members 7a and 7b move to absorb the deviation. As a result, the pressing portions 7a1 and 7b1 come into close contact with the recording sheet 2 over the entire surface even if there is the above-mentioned deviation.

Even if the deviation is large, even if the pressing member 9b is displaced to a position higher than the pressing member 9a as shown in FIG. 5, for example, the downstream side sheet pressing member 7 is provided.
Although a gap is generated between b and the recording sheet 2, the upward biasing point Q of the torsion coil spring 16 causes the shaft 15 and the pressing portion 7 to move.
Since it is located between b1, the moment force M due to the bias acts in the direction of the arrow in FIG. 5, and the tip of the pressing portion 7b1 is biased so as to contact the recording sheet 2. Therefore, it is possible to prevent the tip of the pressing portion 7b1 from contacting the recording head 6.

On the contrary, even if the pressing member 9a is displaced to a position higher than the pressing member 9b, the leaf springs are the same as above.
Since the upward urging point P by 14 is between the shaft 13 and the pressing portion 7a1, the tip of the pressing portion 7a1 comes into contact with the recording sheet 2 due to the action of the moment due to the urging, and this tip is the recording head. The contact with 6 can be prevented.

In the recording apparatus of the present embodiment, as described above, the sheet pressing members 7a and 7b move so as to be in close contact with the recording sheet 2 even if the position is slightly displaced, and further the sheet pressing is performed. It is possible to prevent the recording head 6 from being damaged by the members 7a and 7b.

[Other Embodiments]

In the above-described embodiment, the pressing members 7a and 7b are used.
Although the leaf spring 14 and the torsion coil spring 16 are provided on the side surface of the carriage 8 opposite to the home position as an urging means, the urging means may be provided on the home position side of the carriage 8. Alternatively, they may be provided on both sides.

Further, as the biasing means, a tension spring, a compression spring or the like may be used as well as the leaf spring 14 or the torsion coil spring 16.

Further, in the above-described embodiment, the sheet pressing members 7a and 7b are provided on the upper and lower sides of the recording position, but the members may be provided only on the upstream side or the downstream side of the recording position. May be.

Further, although the ink jet recording method is used as the recording means in the above-mentioned embodiment, the electrothermal converter is energized in response to a recording signal, and bubbles are generated due to heating beyond the film boiling by the electrothermal converter. More preferably, the ink is ejected from the ejection port to perform recording. With regard to its typical structure 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 gives a rapid temperature rise exceeding nucleate boiling, thermal energy is generated in the electrothermal converter, and the electrothermal converter is heated. 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 this drive signal. Due to the growth and contraction of the bubbles, the liquid is ejected through the ejection opening 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 of 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 discharge 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 discloses a structure in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and a discharge portion having an opening for absorbing a pressure wave of thermal energy is disclosed. The effect of the present invention is effective even if the configuration based on Japanese Patent Laid-Open No. 59-138461, which discloses the configuration corresponding to the above, is adopted. That is, according to the present invention, recording can be reliably 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 configuration that satisfies the length by combining a plurality of recording heads or a configuration 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 recovery means for the recording head, preliminary auxiliary means, etc., which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. Specific examples thereof include capping means, cleaning means, pressurizing or suctioning means for the recording head, preheating means by electrothermal conversion type or other heating element or a combination thereof, and recording. It is also effective to perform stable recording by performing a preliminary discharge mode in which another discharge is performed.

Regarding the type or 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 having at least one of the full colors according to

In addition, although the ink is described as a liquid in the above-mentioned embodiments, it is an ink that solidifies at room temperature or lower and softens or liquefies at room temperature, or in the ink jet recording system. 30 inks
It is common to adjust the temperature within the range of ℃ to 70 ℃ to control the viscosity of the ink so that it 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 a solid state to a liquid state, or to use ink that solidifies when left standing for the purpose of preventing ink evaporation. However, in any case, when heat ink is liquefied by application of heat energy according to a recording signal and liquid ink is ejected, or when the ink reaches a recording sheet, it begins to solidify. 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 disclosed in JP-A-54-
As described in JP-A-56847 or JP-A-60-71260, a form in which it is opposed to an electrothermal converter in a state of being held as a liquid or a solid in a recess or 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 an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and further a facsimile apparatus having a transmitting / receiving function. It may be 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 is not limited to the ink jet recording method, and other thermal transfer recording method, heat sensitive recording method, Can also be applied to a recording method other than the non-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.

[0044]

As described above, according to the present invention, when the carriage moves during recording and the pressing member presses the pressing member, the entire pressing member comes into contact with the recording medium even if a positional deviation occurs. Thus, the floating of the recording medium can be surely prevented, and the distance between the recording unit and the recording medium can be stably maintained. Further, if the biasing position of the pressing member is located between the rotating shaft and the pressing member, even if the pressing member and the recording medium are not completely in contact with each other,
It is possible to prevent the tip of the pressing member from coming into contact with the recording medium and damaging the recording means at the tip.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional explanatory diagram of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of a main part of the recording apparatus.

FIG. 3 is an explanatory view of a state where a sheet pressing member is separated from a platen.

FIG. 4 is an explanatory view of a state where a recording sheet is pressed against a platen by a sheet pressing member.

FIG. 5 is an explanatory diagram when a difference occurs in height of the pressing member.

FIG. 6 is an explanatory diagram of a conventional technique.

FIG. 7 is an explanatory diagram of a state in which the leading end of the sheet pressing member contacts the recording head.

FIG. 8 is an explanatory diagram of a state in which a gap is generated between a sheet pressing member and a recording sheet.

[Explanation of symbols]

 2 ... Recording sheet 4 ... Sheet conveying means 5 ... Platen 6 ... Recording means 7 ... Sheet pressing member 7a ... Upstream sheet pressing member 7b ... Downstream sheet pressing member 7a1, 7b1 ... Pressing portion 7a2, 7b2 ... Arm portion 7a3, 7b3 ... Inclined part 8 ... Carriage 9 ... Pressing member 9a ... Upstream pressing member 9b ... Downstream pressing member 10 ... Ejection trays 11, 12 ... Slot 13 ... Shaft 14 ... Leaf spring 15 ... Shaft 16 ... Torsion coil spring

Claims (1)

Claim: What is claimed is: 1. A recording unit for recording on a recording medium conveyed onto a platen, and a carriage which is equipped with the recording unit and is capable of reciprocating in a recording area for the recording medium. A pressing member that is disposed on at least one of an upstream side and a downstream side in the recording medium transport direction with respect to the recording area and is displaced to press the recording medium against the platen, and the pressing member is displaced by the movement of the carriage. And a pressing member for holding the pressing member, and the pressing member is attached so as to be rotatable about a rotation shaft and movable with respect to the rotation shaft. 2. The recording apparatus according to claim 1, wherein the pressing member is configured to be urged in a direction opposite to a pressing direction of the pressing member between the rotating shaft and a pressing position of the pressing member. 3. The recording apparatus according to claim 1, wherein the recording apparatus is an inkjet recording system in which a recording unit ejects ink in accordance with a signal to perform recording. 4. The recording apparatus is an ink jet recording system in which 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 according to claim 3. 5. In the recording apparatus, the recording means energizes the electrothermal converter in response to a signal, and the ink is ejected from the ejection port due to the growth of bubbles caused by heating beyond the film boiling by the electrothermal converter. The recording apparatus according to claim 4, wherein the recording apparatus is an inkjet recording method for performing recording.