JPH04197668A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To make stable and constant recording of images possible regardless of differences in thickness and quality of material on which the recording is made by providing a gap adjustment means that adjusts a gap between a platen and a recording means by detecting or indicating the thickness of the material on which the recording is made. CONSTITUTION:As a material P on which recording is made is transferred to a position between a lower resist roller 5 and a pressing roller 5a, an arm 28 pressed to the pressing roller 5a with a spring 30 turns round a pivot 29. An index 28a is provided to the arm 28. The position of the index 28a determined after the turning of the arm 28 is detected with a line sensor 31, and thereby the thickness of the supplied material P on which the recording is made is measured. After that, the measured thickness of the material P on which the recording is made and the position of a head holder 52 detected by a line sensor 36 are inputted into a comparator C. Then a motor 34 is run based on the result of the comparison, and the head holder 52 is moved therewith toward a platen 24 until a gap (d) between the said holder and the platen 24 becomes nil. Thereby an optimum distance can be maintained between a recording means H and the material P on which the recording is made.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording apparatus that performs recording by ejecting ink from a recording means onto a recording material.

[Conventional technology: Used in conjunction with computers, word processors, etc.
Alternatively, a recording device such as a printer, a copying machine, or a facsimile machine used alone is configured to form an image on a recording material such as paper or a thin plastic plate based on image information.

Depending on the recording method, the recording device may be an ink-end type,
It can be divided into wire dont type, thermal type, and laser beam type calculation.

Among these, the inkjet type (inkjet recording device) performs recording by ejecting ink from the recording means onto the recording material, and can record high-definition images at high speed.It is a non-impact type, so it produces less noise. It has the advantage that it is easy to record color images using multicolor ink.

In particular, the recording means (recording throat) of inkjet 2, which uses heat as ink ejection energy, uses etching,
Through semiconductor manufacturing processes such as vapor deposition and sputtering,
By forming electrothermal transducers, electrodes, liquid path walls, top plates, etc. on a substrate, it is possible to easily manufacture a device with a high density liquid path arrangement N (discharge port arrangement). can.

Conventionally, in this type of inkjet recording device, the flying speed of the ejected ink is fast and the flying direction is constant, so the distance between the ejection orifice surface of the print head and the recording surface of the recording material is 0 to 0.
It was said to have a fairly large allowable range of about 2.0m+.

Therefore, the distance between the recording head and the platen has been set to a sufficiently wide constant value so that the ejection port surface or the head holder does not come into contact even with the thickest expected recording material.

[Technical problem 8 that the invention seeks to solve] However,
In recent Victorian color recording, that is, recording by mixing multiple colors, it has become necessary to record images of each color at precise positions.

In particular, as the diameter of the ejection orifices becomes smaller due to higher density and higher definition, the speed of flying ink decreases and the amount of wobbling increases. It has become necessary to regulate it.

Also, if the above interval is too small or large,
When the thickness or material of the recording material differs, image conditions such as color, satellites, wrinkles, etc. change, and the image tends to be different from that of the standard recording material.

Therefore, a method has been proposed in which the image processing circuit is switched depending on the type of recording material, but this method is difficult to put into practical use, and it is also difficult to precisely match the image condition. .

In addition, a method has been proposed in which a space roller is provided on the recording head holding member (head holder) and the space roller is moved or slid over the recording material to maintain a constant distance between the recording throat and the recording material. This method is unsuitable for high-definition color recording because vibrations occur due to the steps at both ends of the recording material and vibrations occur due to sliding on the recording material, which adversely affects the ink ejection state. Furthermore, there is a technical problem that needs to be solved in that the recording material gets dirty due to the dirt on the rollers.

The present invention has been made in view of the above technical problems, and
An object of the present invention is to be able to perform stable and constant image recording even when the thickness and material of the recording material differs, and to prevent friction between the recording material and the recording head and paper jams. It is an object of the present invention to provide an inkjet recording device that can be used in various ways and that can be improved in ease of handling.

[Means for solving problems]

The present invention provides an inkjet recording apparatus that performs recording by discharging ink from a recording means onto a recording material, and a platen for holding the recording surface of the recording material by detecting or indicating the thickness of the recording material. By having a gap adjusting means for adjusting the distance between the recording medium and the ejection orifice surface of the recording means, it is possible to perform stable image recording even when the thickness and material of the recording material differs, and An object of the present invention is to provide an inkjet recording device that can prevent friction between a recording head and the like and paper jams, and can also improve ease of handling.

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

Note that the same reference numerals on each of the seven sides indicate the same or corresponding parts.

FIG. 2 is a schematic cross-sectional view showing the overall configuration of an inkjet recording apparatus according to an embodiment of the present invention.

In FIG. 2, a roll paper 1, which is one of the recording materials P, passes through a turn roller 2 and a feed roller 3, and then passes through a counter 4.
The paper passes through the gap between the rollers, is further fed by the lower registration rollers 5, and is stopped while being nipped by a conveyance means composed of a conveyance roller 6, a rubber roller 7, and a pressure roller 8.

Note that by controlling the stop timing of each of the rollers described above, the slack in the roll paper (recording material) l can be taken up.

Between the lower registration roller 5 and the conveyance roller 6,
A platen 24 is provided to support the third recording surface of the recording material 1 from the back side.

A carriage 25 that reciprocates in the width direction of the recording material 1 is provided at a position facing the platen 24, and a recording means (recording head) H is mounted on the carriage 25.

When the recording material 1 is fed to the transport roller 6 and stopped, the air inside the platen 24 is sucked, and the recording material 1 is brought into close contact with the platen 24 to keep the recording surface flat.

In this state, the recording means H is moved in the width direction of the recording material 1 (in the direction perpendicular to the paper surface in FIG. 2) to record one line.

The recording means (recording head) H is for color recording and is composed of four recording heads that record with different ink colors.

For example, cyan, magenta, yellow, and black are used as ink colors for the four recording heads.

In the following explanation, the term "recording means (recording head)" will be used both when referring to all of the above four recording means (recording heads) and when referring to any one of the four recording means. I will show you.

After finishing recording one line by the recording head H of each color,
The recording material 1 is fed by one line (wl feed) in preparation for recording the next line.

The reciprocating movement of the recording means H is performed by moving the carriage 25 along the guide shafts 26, 27.

A blower B is mounted on the carriage 25 for cooling the recording means H that discharges ink using thermal energy.

Further, when the roll paper 1 is fed to a suitable length, the trailing end is cut by a cutter 4, and after further necessary recording is performed, it is discharged through a guide 9.10.

Cant sheets, which are other recording materials P, are loaded in the cassette 11, and 20 cut sheets 1 are fed out one by one by the paper feed roller 12, and after the leading edge is aligned by the registration roller 13. , Guide 14.16.18.20
．． 23 and feed rollers 15, 17, 19, and 22, and further, after aligning the leading edge again with the lower registration roller 5, 1. As in the case of the roll paper 1 described above, it is held between the transport means 6.7.8, and then recorded by the same operation as described above.

In the case of a cut sheet, there is no need to cut it, and after recording, the cut sheet is discharged as it is through the guide 9.10.

Further, the manually fed recording material P (usually a cut sheet) is inserted through the feed roller 21 and fed to the lower registration roller 5 through the feed roller 22 and the guide 23, and thereafter follows the same route as in the case of the cut sheet described above. The paper is fed along the paper, recorded by similar paper feeding and recording operations, and then ejected in the same manner.

The inkjet recording apparatus shown in FIG. 2 includes a printer section Pr and a reader section Re.

The information recorded by the recording means H may be either character information (not shown) or image information output from a reader (reading device) Re.

The reader (reading device) Re is configured to read the information of the document illuminated by a lamp using a CCD focused by a lens F, and output this as an electric signal (image information).

The recording means (recording gutter) H is a recording means that discharges ink using thermal energy, and is equipped with an electrothermal converter for generating thermal energy.

Further, the recording means H performs recording by ejecting ink from an ejection port using pressure changes caused by growth and contraction of bubbles due to film boiling caused by thermal energy applied by the electrothermal converter. It is.

FIG. 3 is a partial perspective view schematically showing the structure of the ink ejection section 50 of the recording means (recording nozzle) H.

In FIG. 3, a predetermined gap (for example, approximately 0
．． A plurality of discharge ports 52 are formed at a predetermined pitch on the discharge port surface 51 facing each other with an interval of 5 to 2.0 steps), and each liquid path 54 communicates the common liquid chamber 53 with each discharge port 52. An electrothermal transducer (such as a heating resistor) 55 for generating energy for ink ejection is disposed along the wall surface of the ink.

In the inkjet recording apparatus shown in the second area, the recording means (
To recording/7)H, the ejection port 52 is connected to the carriage 25.
They are mounted on the carriage 25 in a positional relationship such that they are lined up in a direction intersecting the scanning direction (moving force ril).

In this way, the corresponding electrothermal transducer 55 is driven (energized) based on the image signal or ejection signal, the ink in the liquid path 54 is brought to film boiling, and the ink is ejected from the ejection port 52 by the pressure generated at that time. Recording means (recording head)
H is configured.

The inkjet recording apparatus described above includes a recording material P.
A gap adjusting means is provided to make the distance between the recording material P held on the platen 24 and the ejection port surface 51 of the recording means H constant regardless of the thickness.

FIG. 1 is a partial cross-sectional view showing the structure of this gap adjustment means.

In FIG. 1, when the recording material P is fed between the lower registration roller 5 and the pressure roller 5a, the arm Δ28 pressed against the pressure roller 5a by the handle 30 rotates around the rotating shaft 29.

An indicator 28a is provided on the arm 28,
The line sensor 31 is configured to detect a change in the position of the index 28a due to the rotation of the arm 28.

Therefore, by detecting the position of the index 28a with the line sensor 31, the thickness of the fed recording material P can be measured.

Although the rotation angle of the arm 28 when the recording material P is fed is small, the position of the index 28a is set to have a sufficient leverage ratio with respect to the rotation center 29.
It can be easily detected by the line sensor 31.

The recording means (recording head) H is held by a head holder 32, and the acid head holder 32 can be moved forward and backward by a holder rail 33 provided on the carrier 25, that is,
Two platens 24 are held in such a way that they can be approached and separated.

The head holder 32 is provided with an index 32a, the position of which is detected by a line sensor 36 on the carriage 25.

The thickness of the recording material P detected by the line sensor 31 and the position of the head holder 32 detected by the line sensor 36 are input to a comparator C.

A comparator C compares the two, and based on the comparison result, the motor 34 is rotated, and the screw 35 fixed to the output shaft of the motor 34 is rotated, whereby the head screwed into the screw 35 is rotated. The holder 32 is moved forward and backward, and the nodule holder 32 is placed in the optimum position.

The optimal position of this hemlock holder 32 is the position where the distance between the recording means H and the recording material P becomes the optimal gap.

Note that the blower B for cooling the recording means H can be moved back to the dotted line position when replacing or maintaining the recording means H.

Furthermore, regarding the thickness G of the recording material P, instead of using the measured value by the line sensor 31, a thickness instruction signal S (dotted line) input from an operation bar (not shown) or the like is used. However, it is also possible to perform similar control by inputting this to comparator C.

According to the embodiment described above, the recording means H and the recording material P
Since we have provided a gap adjustment means that always adjusts the distance between It was possible to maintain it.

For example, even when using a recording material that is different in stiffness, thickness, or image processing from standard recording materials such as cloth or cardboard, the recording material may rub against the recording means H. Furthermore, it is now possible to prevent failures such as the recording material coming into contact with the head holder 32 and causing tearing or paper jams.

In addition, since the gap between the recording means H and the recording material P is automatically adjusted, recording materials made of a wide variety of materials can be used without the need for complicated adjustments or assembly repairs. became possible.

Furthermore, depending on the temperature and humidity, it may be necessary to widen or narrow the gap between the recording means H and the recording material P in order to stabilize the paper feeding operation, but according to the above embodiment,
Gap adjustment in such cases can be easily and automatically performed, making it possible to perform highly stable recording operations.

FIG. 4 is a vertical cross-sectional view showing the structure of the gap adjusting means between the recording means and the recording material of an inkjet recording apparatus according to another embodiment of the present invention, and FIG. FIG.

In FIG. 4, the platen 2 is
4 and the recording means (recording gutter) H is performed, the recording material P is fed to the position of the platen 24.

The selection operation for setting the interval is performed by detecting the recording material P using a sensor or the like.
This can be done automatically by detecting the thickness of the recording material, or it can be specified from the operation pulse, and it can also be used when manually feeding a recording material with an unexpected thickness. can be done.

Before the recording material P is fed to the position of the platen 24,
The head holder 32 is retracted to the position indicated by the dotted line in FIG.

When the recording material P is fed to the position of the platen 24, the head holder 32 is moved to the recording position shown by the solid line in FIG.

In this embodiment, the holder rail 33 is the carriage 2
The hemlock holder 32 is mounted so as to be movable forward and backward with respect to the holder rail 33.

Further, the head holder 32 is always urged toward the platen 24 by a spring 37.

Further, on both sides of the front surface of the head holder 32, rollers 36a and 36b that can come into contact with the platen 24 are rotatably supported around a vertical axis.

Note that these rollers 36a and 36b protrude from the recording means H (its ejection port surface 51) by an amount corresponding to the optimum distance between the recording material P and the recording means H (for example, 05an).

Therefore, as described above, when the head holder 32 moves from the dotted line position to the solid line position in FIG.
2 is pushed in the direction of the platen 24 by the springs 37, but since the rollers 36a and 36b ride on the platen 24, it retreats by that amount.

In this way, when the head holder 32 rides on the recording material P on the platen 24 and retreats, the head holder 3
There is a gap d (FIG. 4) between the recording means H and the holder rail 33, but by moving the holder rail 33 until this gap d becomes 0 (zero), the recording means H and the recording material P The distance between the two can be set to an optimal value.

Specifically, by rotating the motor 34, the screw 3
5 to move the holder rail 33 to the right in FIG.

That is, until the contact 33b of the holder rail 33 comes into contact with the contact 32b of the head holder 32, the holder rail 3
Move 3.

FIG. 6 shows an example of the electric circuit of the gap adjustment means shown in FIG. 4. In the same figure, the circuit uses a switch K that closes when the contacts 32b and 33b are open and opens when they are closed. Just leave it there.

Further, the rollers 36a and 36b may be in contact with the recording material P, but may also be slightly floating.
If the rollers 36a and 36b are floating, they do not come into contact with the recording material P, which is advantageous.

In this way, the rollers 36a are
, i6b do not contact, by utilizing the response delay of the switch, contact 3 of the switch is set.
Even if 2b and 33b are closed, the inertia of the motor 34 may cause the motor to rotate a little. Alternatively, a delay circuit may be used in advance for several seconds after the switch K is closed (in the case of a step motor). You can set it so that it rotates an extra few steps).

According to the embodiment described above with reference to FIGS. 4 and 5, in addition to obtaining the same effects as in the embodiment shown in FIG.
Even when the recording material P is not adsorbed perfectly to the platen 24, the rollers 36a and 36b squeeze the recording material P, thereby preventing paper jams and paper stains if the paper is torn by the head holder 32. It worked.

Note that the thickness detection and gap adjustment of the recording material P in each of the above embodiments may be performed each time a recording operation is performed, or each time the recording material P such as a roll paper is replaced.

Further, in detecting the thickness of the recording material P, in addition to directly detecting the thickness, a preset thickness can be identified by detecting the type of paper.

The type of paper can be detected by, for example, the amount of light reflection or the degree of light transmission.

FIG. 7 is a schematic diagram illustrating a state in which the type of recording material is detected by a reflective sensor.

In FIG. 7, a reflection sensor S is installed at a portion where the recording material P passes through, and the sensor S detects the recording material P.
Detects the reflection density of the base surface (back surface) of the recording material, calculates the thickness of the recording material corresponding to this value in advance, and adjusts the distance between the recording means H and the recording material P based on this calculated thickness. It can be controlled to the optimum value.

In the 7th session, (A) is when the recording material P is double-sided coated paper Pa, (B) is when single-sided coated paper Pb, (C)
(D) shows the case of film Pc, and (D) shows the case of thick paper Pd, and the relationship between the reflection density and paper thickness of these recording materials is as follows.

Reflection density OD Paper thickness TH Pa Double-sided coated paper 0.07 140 μPb Single-sided coated paper 0.13 110 μPc film
0.5 180μPd thickness 0.3
When the OD value is 0.1 or less, it is determined that the paper is coated on one side, and the paper is sent for recording.

If 0.5 .mu. is appropriate for the gap between the plates, the gap between the platen 24 and the recording means H should be 640 .mu..

When the OD value is 0.22 to 0.4, it is determined to be cardboard, and 720
It should be μ.

In addition, instead of the reflection density of the recording material P itself, for example, by printing a bar code signal or a predetermined color as an indicator on the paper wound around the core of the roll paper, and detecting it. By detecting the thickness and material of the paper, typically, the distance between the platen 24 and the recording means H and, incidentally, the image processing may be switched. By detecting the material, it is also possible to select an optimum interval specific to the material, rather than a fixed interval, according to the above-described embodiment.

Further, the physical size such as the width and diameter of the roll paper or the core may be changed depending on the type of paper.

When detecting or specifying the type of recording material (paper), it is also possible to control to change factors other than the distance between the recording head H and the platen 240, such as the amount of ink and the feed speed. It is.

Note that each of the above embodiments has been described using as an example a case where the invention is applied to a Norreal type inkjet recording apparatus in which a recording means (recording head) H is mounted on a carriage 25 that moves along a recording material P. The present invention can be similarly applied regardless of the type of scanning method, such as a line-type inkjet recording device that uses a line recording means with a length corresponding to the whole or part of the recording slope in the width direction of the recording material. can be used to achieve similar effects.

Further, in each of the above embodiments, the case of a color inkjet recording apparatus equipped with a plurality of recording means (recording heads) H for recording in different colors has been described as an example, but the present invention
It can be applied in the same way regardless of the number of recording means, such as an inkjet recording device that records with one recording means, or an inkjet recording device for gradation recording that uses multiple recording means of the same color but different density. It is possible to achieve the following effects.

Furthermore, the recording means (recording nozzle) H in each of the above embodiments may be a replaceable cartridge type recording means that integrates a recording head and an ink tank, or
Recording means having various structures can be used, such as a recording means having a structure in which the recording head and the ink tank are separated and connected via a coupler and a tube, for example.

The present invention can be applied to any inkjet recording device that uses a recording means (C recording head) that uses an electromechanical transducer such as a piezo element, but is particularly applicable to the inkjet recording device proposed by Canon Co., Ltd. This brings about excellent effects in the Hubblejesoto inkjet recording apparatus.

This is because, according to such a system, higher recording density and higher definition can be achieved.

As for typical configurations and principles thereof, it is preferable to use the basic principles disclosed in, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740,796.

This method can be applied to both the so-called on-demand type and the continuous type, but in the case of the on-demand type, it is especially applicable to the sheet holding the liquid (ink) and the liquid path. by applying at least one drive signal to the disposed electrothermal transducer that corresponds to recorded information and provides a rapid temperature rise above film boiling;
The electrothermal converter generates thermal energy, and the recording means (
This method is effective because it causes film boiling on the heat-active surface of the recording nozzle, resulting in the formation of bubbles in the liquid (ink) in one-to-one correspondence with this drive signal.

Due to the growth and contraction of these bubbles, liquid (
eject ink) to form a small droplet (at least one droplet).

If this drive signal is in the form of a pulse, bubble growth and contraction will occur immediately and appropriately, so liquids with particularly excellent responsiveness (
Ink) can be ejected, which is more preferable. As this pulse-shaped drive signal, those described in US Pat. No. 4,463,359 and US Pat. No. 4,345,262 are suitable.

Further, if the conditions described in US Pat. No. 4,313,124 concerning the temperature increase rate of the heat acting surface are adopted, even more excellent recording can be achieved.

The configuration of the recording head includes a combination of ejection ports, liquid paths, and electrothermal converters (straight liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, as well as a heat-acting section. U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600 disclose a configuration in which the
The present invention also includes a configuration using the specification of the present invention.

In addition, Japanese Patent Application Laid-open No. 123670 of 1982 discloses a configuration in which a common slit is used as a discharge part for a plurality of electrothermal converters, and a hole that absorbs pressure waves of thermal energy is disclosed. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461 of 1981, which discloses a configuration in which a discharge portion corresponds to a discharge portion.

That is, no matter what form the recording is made, according to the present invention, recording can be performed reliably and efficiently.

Furthermore, the present invention can be effectively applied to a full-line type recording pent' having a length corresponding to the maximum width of a recording medium that can be recorded by a recording apparatus.

Such a recording head may have a configuration in which the length is satisfied by a combination of a plurality of recording heads, or a configuration as a single recording head formed integrally.

In addition, even for serial types such as top strips, the recording head is fixed to the main body of the device, or is installed in the main body of the device, so that electrical connection with the main body of the device and ink from the main body of the device are not possible. The present invention is also effective when using a replaceable chip-type recording nozzle that can supply ink or a cartridge-type recording head in which an ink tank is integrally provided in the recording head itself.

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, to the present invention because the effects of the present invention can be further stabilized.

Specifically, these include capping means, cleaning means, pressurizing or suction means, electrothermal transducers or other heating elements, or a combination of these for the recording throat. It is also effective to perform a preliminary ejection mode in which a preheating means and ejection other than printing is performed in order to perform stable printing.

In addition, regarding the type and number of recording heads installed, for example, in addition to one type that corresponds to a single color of ink, or a plurality of recording heads that correspond to multiple ink heads of different recording colors and densities, It may be provided.

That is, for example, the recording mode of the recording apparatus is not only a recording mode for mainstream colors such as black, but also whether the recording head is configured integrally or by a combination of multiple heads.
Although any of these may be used, the present invention is also extremely effective for devices equipped with at least one of multiple colors of different colors or full colors created by mixing colors.

Additionally, in the embodiments of the present invention described above,
Although the ink is described as a liquid, it is an ink that solidifies at room temperature or lower, but softens or liquefies at room temperature, or in the inkjet method, the ink itself is heated within a temperature range of 30°C or higher and 70°C or lower. Generally, the temperature is adjusted to keep the viscosity of the ink within a stable ejection range, so it is sufficient if the ink is in a liquid state when the recording signal f is applied.

In addition, the temperature rise caused by thermal energy can be actively prevented by using it as energy to change the state of the ink from a solid state to a liquid state, or ink that solidifies when left standing for the purpose of preventing the ink from forming a straw. In any case, the ink is liquefied by applying thermal energy in accordance with the recording signal, and the liquid ink is ejected, or the ink already begins to solidify by the time it reaches the recording medium. Note that the present invention is also applicable when using ink that is liquefied only by thermal energy.

In such cases, the ink is held in a liquid or solid state in the recesses or through holes of the porous sheet, as described in JP-A-54-56847 or JP-A-60-71260. , it may also be in a form that faces the electrothermal converter.

In the present invention, the most effective method for each of the above-mentioned inks is to implement the above-mentioned film boiling method.

In addition, the inkjet recording device according to the present invention can be used as an image output terminal for information processing equipment such as a computer, a copying device combined with a league etc., or a facsimile device having a transmitting/receiving function. It may also be something that is harvested.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in an inkjet recording apparatus that performs recording by ejecting ink from a recording means onto a recording material, the thickness of the recording material can be detected or indicated. Since the structure has a gap adjustment means for adjusting the distance between the platen for holding the recording surface of the material and the ejection opening surface of the recording means, stable image recording can be achieved even when the thickness and material of the recording material differs. In addition, it is possible to effectively prevent friction between the recording material and the recording bed, etc., and paper jams.
An inkjet recording device is provided that can improve handling by a large fF.

[Brief explanation of the drawing]

The first part is a longitudinal cross-sectional view showing the structure of the gap adjusting means of the recording means of the inkjet recording apparatus according to an embodiment of the present invention, and the second part is a longitudinal cross-sectional view showing the overall structure of the inkjet recording apparatus according to an embodiment of the present invention. 3 is a partial perspective view schematically showing the structure of the ink ejection section of the recording means in FIG. 1, and FIG. 4 is a partial perspective view of the recording means of an inkjet recording apparatus according to another embodiment of the present invention. A vertical cross-sectional view showing the structure of the gap adjustment means,
Figure 5 is a cross-sectional plan view taken along line v-■ in Figure 4;
The figure is a switch circuit diagram of the gap adjusting means in FIG. 4, and FIGS. 7A to 7D are schematic diagrams each showing a state in which the type of recording material is detected. Below, symbols representing main components in the drawings are listed. 1--Roll paper, 5--Lower registration roller, 5
a--1--=pressing roller, 6----conveying roller, 1
1- = Paper feed cassette, 22-- Feed roller, 24--
--Platen, 25--Carriage, 26.27---
--Guide shaft, 28 Arm, 30--Hane,
31-----Line sensor, 32-Head holder, 32 b--Contact, 33--Holder rail, 33b--One contact, 34--Motor , 36-----line sensor, 36a, 36 b-
- roller, 51-one discharge port surface, 52----one discharge port,
55---Electrothermal converter, C-1---Comparator, H-
---Recording means (recording head), P--Recorded material, S
-1---Thickness indication signal, d-1---Gap
. (弼!-Niyun 4 Agent Patent Attorney Yasuyuki Oon Figure 6 Figure 7 (A) (B) (C) (D,)

Claims (3)

[Claims] (1) In an inkjet recording device that performs recording by ejecting ink from a recording device onto a recording material, a platen is used to hold the recording surface of the recording material by detecting or indicating the thickness of the recording material. An inkjet recording apparatus characterized by having a gap adjustment means for adjusting the distance between the recording means and the ejection port surface. (2) A claim characterized in that the recording means is an inkjet recording means that ejects ink using thermal energy, and is equipped with an electrothermal converter for generating thermal energy. Item 1. The inkjet recording device according to item 1. (3) The recording means is characterized in that the ink is ejected from the ejection port by utilizing a state change caused by the growth of bubbles due to film boiling caused by the thermal energy applied by the electrothermal converter. 2. The inkjet recording device according to 2.