JP3200098B2 - Ink jet recording head and ink jet recording apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head applicable to a printer, a copying machine, an ink jet recording apparatus and the like generally used for office machines, and more particularly to a recording head detachable from a main body of the apparatus.

[0002]

2. Description of the Related Art A conventional ink jet recording apparatus, recording head, and recording unit integrated with an ink tank are capable of ejecting fine droplets, an electromechanical transducer, an electrothermal transducer, or a composite form thereof, or a pair of them. There is known an electrode provided with an electrode for deflecting and discharging a droplet.

Among them, an ink jet recording head which discharges a recording liquid by utilizing thermal energy has a high density of liquid discharge portions (orifices) for discharging a recording liquid droplet to form a flying liquid droplet. In addition to being capable of performing high-resolution printing, it has been put to practical use because of its advantages such as high-speed printing due to easy multi-nozzle operation.

FIGS. 9, 10 and 11 show a conventional example of an ink jet recording head utilizing thermal energy.
In FIG. 9D, reference numeral 1003 denotes a heater board having thermal energy generating means (discharge heater) 1005;
010 is ink, and 17 is a grooved top plate that forms a part of the ink flow path. The ink 1010 is supplied from an ink flow path formed by a heater board 1003 and an ink flow path 17 as shown by an arrow A, and is heated by an ejection heater 1005 on the heater board 1003 to be heated by an orifice 1002.
The recording is performed by discharging in the direction of arrow B. FIG.
(A) to (c) show the arrangement inside the heater board 1003, 15 is a wiring section, 16 is a diode array section, and 1004 is a pad section for electrically connecting the heater board 1003 to the outside. It is. Discharge heater section 1005, wiring section 15, pad section 1 from discharge port 1002 side
004. A discharge heater section 1005, a wiring section 1004, a diode array section 16, and a pad section 1004 are arranged from the discharge port 1002 side. FIG.
FIG. 9B shows the arrangement in the heater board 1003 in the case where the wiring section 1004 and the diode array section 16 are mixed, although the electrical connection is the same as that of FIG. 9A.

Conventionally, electrical connections in the heater board 1003 shown in FIGS. 10 and 11 have been proposed and put to practical use. FIG. 10 shows individual discharge heaters 10.
FIG. 11 shows an electrical connection in a heater board 1003 having an individual pad 18 corresponding to the one-to-one 05 and a common pad 1 for applying a voltage V _H to the discharge heater 1005, according to image data. Individual pads 18 and V
_This is a direct drive system in which a drive voltage is applied to the _H pad 1 to heat the discharge heater 1005 to perform discharge. The arrangement inside the heater board 1003 of this type
The one shown in FIG. 9C is generally used.

FIG. 11 shows an electrical connection in a heater board 1003 in which a diode 19 and a heater 1005 are arranged at the intersection of a vertical wiring and a horizontal wiring. By selectively applying a drive voltage to the wiring pads 21, only a discharge heater 1005 in which a voltage is printed on both the vertical and horizontal pads is heated and discharge is performed. The arrangement in the heater board 1003 of this type is based on FIG.
What is shown in (b) is common.

[0007]

However, in the direct drive system shown in FIG.
05, n individual pads 18 are required, and one V _H pad is also required.
1) One pad is required. In addition, since the individual pads 18 are directly connected to the discharge heater 1005, each of the individual pads 18 has a large current (in the example of the experiment by the present inventors, a nozzle density of 360 d
150 mA at 7 μS pulse width with pi plain paper compatible head
) Flows, and n times more current flows through the _VH pad, and all the wirings become power supply lines through which a large current flows.

In the matrix drive system shown in FIG. 10, when n discharge heaters 1005 are arranged, the number of pads is at least 2√n (however, if 2√n is not an integer, the first digit below the decimal point is rounded off). Pad is added). In addition, the current flowing through each pad is also equal to (the number of discharge heaters 1005 wired in a matrix × the current per discharge heater).
All the wirings become power supply lines through which a large current flows.

As described above, in the conventional head, in order to reduce the voltage drop due to the wiring as much as possible, the size of the wiring in the heater board 1003 corresponding to the current value, the size of the wiring, the size of the pad, and the size of the wiring taken out from the heater board are considered. The thickness and routing must be considered.

[0010] For this reason, when a high-density multi-nozzle is used, wiring becomes complicated, resulting in an increase in the size of the device, an accompanying increase in cost, and a decrease in reliability.

[0011]

Means for Solving the Problems] inkjet recording head of the present invention, a plurality of heat generating resistive elements arranged in order to eject ink from the ejection opening, is electrically connected to the heat generating resistive element the Symbol heating resistor A functional element for selectively driving the element, and an integrated circuit for receiving serial image data and outputting the serial image data as a parallel signal to the functional element. An ink jet recording head in which a plurality of semiconductor substrates are arranged, wherein the integrated circuit outputs the received serial image data as a parallel signal to the functional element, and serially outputs image data to the adjacent semiconductor substrate. The semiconductor substrate receives serial image data from outside and supplies it to the integrated circuit. A signal input section that is characterized in that a signal output unit for outputting serial image data in the adjacent arranged substrates is provided that is output from the integrated circuit. According to such a configuration, since image data is sequentially transferred from the semiconductor substrate to the semiconductor substrate, a long recording head can be easily obtained only by increasing the number of semiconductor substrates. Further, it is not necessary for the apparatus side to individually supply signals to each substrate, and the apparatus side can simply transmit data serially, so that the apparatus configuration can be simplified.

[0012]

FIG. 1 shows an embodiment of the present invention and is an electrical connection diagram on a heater board 1003. FIG. FIG. 2 shows a timing chart of the operation. In FIG. 1, reference numeral 1005 denotes a discharge heater which has _n heaters R _{1 to} R _n . 1015, 1016 are transistors, 1023 is logic gate logic, 1010
24 indicates a latch circuit, and 1025 indicates a shift register circuit. 1 to 7 are pads, 1 is a _VH pad, 2 is a GND pad, 3 is a strobe pad, 4 is a latch pad, 5 is a data pad, 6 is a clock pad,
7 is a logic power supply _VDD pad. The operation of FIG. 1 will be described below with reference to the timing chart of FIG.

The clock 6 and the serial data 5 synchronized therewith are supplied to the shift register circuit 10 at the timing shown in FIG.
25. By inputting a latch signal (negative logic) as shown in FIG. 2 to the latch circuit 1024 in a state where all the n data are set, the data is held.
This data is maintained until the next latch signal is input. In this state, strobe 3 (negative logic) is shown in FIG.
Is input, a logic gate logic 1023
The output obtained by ANDing the strobe 3 with the latch output is input to the transistors 1015 and 1016,
Drive signals (output signals of transistors) for the heaters R _{1 to} R _n are generated. In this embodiment, the driving waveform of the heater is determined by the input waveform of the strobe 3.

FIG. 3 shows an example in which the electric connection of FIG. 1 is arranged on a heater board 1003. 1005 is a discharge heater, 1004 is a _VH wiring, 1015, 1016
Is a transistor array, 1017 is a GND wiring, 14
Represents a logic circuit portion, and seven pads are formed in the pad portion 1004.

As can be seen from FIGS. 1 to 3, in the present embodiment, the minimum number of pads required on the heater board 1003 is seven regardless of the number of the discharge heaters 1005. The complexity of electrical wiring due to the formation of nozzles is eliminated. Table 1 shows the number of discharge heaters and the minimum number of pads required on the heater board.

[0016]

[Table 1]

As can be seen from Table 1, the discharge heater 1005
If the number of lines becomes abnormal, the number of pads in this embodiment is smaller than that in the conventional direct drive or matrix drive, and this effect becomes more remarkable as the number of heaters increases. Especially line head (A4 horizontal, 400dp
In the case of i), the number of nozzles is 4736, and the difference between the conventional example and the present embodiment is very large. Further, in the present embodiment, four of the seven signal pads, namely, the throttle 3, the latch 4, the data 5, and the clock 6, are logic signals and are not power supply lines, and do not require a large current. As a result, a space in which electric wiring is less is sufficient.

FIG. 4 shows the configuration of an ink jet head using the heater board 1003. Reference numeral 1001 denotes a top plate having n orifices 1002 and a nozzle groove (not shown) having nozzle grooves in each orifice. The top plate 1001 is associated with the n discharge heater arrays 1005 of the heater board 1003 in a one-to-one correspondence with the nozzles and inks. Form a liquid chamber. The electric pad portion 1004 is disposed at two ends of the heater board 1003 with the top plate 1001 being avoided.
Although not shown in the drawing, the connection is made by a method such as wire bonding, gang bonding, bumping, pressure welding, pressure bonding, or the like, and external electric energy is supplied.

The paired top plate 1001 and heater board 1003 are mounted on an ink tank cover 1006. The ink cover 1006 is paired with the ink tank case 10007 to form an ink tank and store ink therein. Although not shown in the drawing, this ink may have a holding member such as being held by an ink absorber in a tank. Further, the ink passes through the ink supply path of the ink tank cover 1006 and the heater board 100
No. 3 discharge heater array 1005 is connected to the lower portion and reaches the nozzle. This is shown in FIG.
3, 1001 will be described in detail. As described above, the ink is supplied from the supply path of the ink tank cover 1006 to the discharge heater 1005 of the heater board 1003.
Is supplied to the back side near the position where the nozzles are arranged, and passes through the nozzle grooves of the top plate 1001 to reach the respective discharge heaters. Here, the ink is heated by an ejection heater and foams, and is ejected to the outside from the orifice 1002 by the foaming pressure to form dots on the printing paper (not shown). Further, this is shown in the cross-sectional view of FIG. 6, in which the ink 1010 is supplied to the surface of the discharge heater 1005 as shown in FIG.
The ink is discharged like a droplet 1008 by the pressure of No. 9.

FIG. 7 shows a substrate 1003 showing the configuration (cross-sectional view) of the heater board shown in FIG. 3 mainly using silicon, but may be made of any other material capable of forming a semiconductor.
A semiconductor layer 1029 is provided on the substrate 1003, and a semiconductor is formed by a method such as ion implantation. Here 101
5, 1016, 1023, 1024, 1025, 102
6 corresponds to a semiconductor. A first electrical insulating layer 1028 is provided on the semiconductor layer 1029, and a conductor is patterned on the first insulating layer 1028. Although not shown in the drawing, a lower layer may be formed as necessary to form the circuit diagram of FIG. In contact with the semiconductor layer 1029. The first conductor in the upper layer of 1028 is a _VH wiring 1014 for supplying electric energy necessary for foaming, and a ground G for the _VH wiring 1014.
An ND wiring 1017, an enable wiring 1019 for heating the electrothermal transducer 1005 at an arbitrary timing, a latch wiring 1020 for latching print data, a serial data wiring 1021 for supplying serial data, and a timing for determining serial data. This is the clock wiring 1022 to be shifted. Further, a second electric insulating layer 1027 is provided on the first conductor, separated from the second conductor layer, and is contacted with a through hole. First, the discharge heater 1005 is brought into contact with the _VH wiring 1014 through the _VH to heater wiring 1011 through a through hole to supply electric energy. Further, the other end of the transistor 1005 is connected to a collector of the transistor 1015 or 1016 through a through hole of the first insulating layer 1028 via a heater to a transistor wiring 1012. Although the first transistor 1015 and the second transistor 1016 form two columns, multiple columns are arranged in one column on each element layout to improve the area efficiency. For example, in the case where the pitch of each heater is small, a plurality of arrays of the transistor are arranged because the closer to a square, the better the area effect. Further, the other ends (bases) of the transistors 1015 and 1016 are connected to a logic gate and a logic 1023 via a transistor base wiring 1018. This transistor base wiring 1018 is made of polysilicon or the like. The first and second conductive layers are made of a material having a low resistivity, such as aluminum. The other ends (emitters) of the transistors 1015 and 1016 are connected to a GND wiring 1017 via a through hole by a transistor to a GND wiring. The logic gate logic 1023 selectively sends an ON signal to the transistor through the enable wiring 1019.
5 can be heated freely. The wiring 1019 is configured to be able to freely select and heat the discharge heater 1005 with little loss of power even when wiring is complicated with good weak electricity.

FIG. 8 is an external view of an ink jet recording apparatus IJRA to which the present invention is applied. The lead screw 5005 rotates through driving force transmission gears 5011 and 5009 in conjunction with forward and reverse rotations of a driving motor 5013. Groove 50
The carriage HC that engages with the pin 04 is a pin (not shown).
And is reciprocated in the directions of arrows a and b. As a result, the recording head IJC mounted on the carriage HC scans on the paper surface to perform printing. Reference numeral 5002 denotes a paper holding plate which applies paper to the platen 500 in the carriage movement direction.
Press against 0. Reference numerals 5007 and 5008 denote home position detection means for confirming the presence of the carriage lever 5006 in this area by photocouplers and switching the rotation direction of the motor 5013. Reference numeral 5016 denotes a member that supports a cap member 5022 that caps the front surface of the print head. Reference numeral 5015 denotes suction means that suctions the inside of the cap, and performs suction recovery of the print head through the opening 5023 in the cap. Reference numeral 5017 denotes a cleaning blade.
Reference numeral 9 denotes a member that enables the blade to move in the front-rear direction, and these members are supported by the main body support plate 5018. It goes without saying that the blade is not limited to this form, and a well-known cleaning blade can be applied to this embodiment. Also, 50
Reference numeral 12 denotes a lever for starting suction for recovery of suction, which moves with the movement of the cam 5020 engaging with the carriage, and the driving force from the drive motor is controlled by a known transmission means such as clutch switching. .

The capping, cleaning, and suction recovery are configured so that desired operations can be performed at the corresponding positions by the action of the lead screw 5005 when the carriage comes to the home position side area. Each of the configurations described above is an excellent invention when viewed alone or in combination, and shows preferred configuration examples for the present invention.

In the head mounted on such an ink jet recording apparatus, there are a head which can be replaced by a user and a head which cannot be replaced. However, in the configuration of this embodiment, the number of electrical contacts is small, so that the user can replace the head. This is particularly effective because the space for contact points in a compact head is small, so that the head is compact and the reliability at the time of attachment and detachment is improved.

(Other Embodiment) FIG. 12 shows a second embodiment. Compared with the first embodiment (FIG. 1), a clock output 9, a serial data output 10, a latch output 11, and a strobe output 12 are added as delay setting circuit 13, enable pad 8, and logic output for cascade connection. ing.

FIG. 1 is a timing chart showing the operation of this embodiment.
3 will be described below.

As in the first embodiment, the clock 6 and the serial data 5 synchronized therewith are stored in the shift register circuit 10.
25. At this time, if a plurality of heater boards 1003 are cascaded, the number of clocks 6 and data 5 is (the number of cascade connections m × the number n of heaters on one heater board). The data is held by inputting the latch input 4 to the latch circuit 1024 with all the data set.

In this state, the strobe 3 is connected to the delay circuit 1
3 is input. Here, the delay circuit 13 is a circuit in which a delay is arbitrarily set for each heater with respect to the input waveform of the strobe signal 3, and a logical product of the delayed waveform and the latched data signal is taken as an output. . The discharge heater further receives a logical product of the delay output and the enable output 8. Here, the enable output is a plurality of heater boards 1003
When only an arbitrary heater board is to be discharged when the cascade connection is performed, the heater board to be discharged is selected based on this signal.

In this embodiment, an arbitrary delay can be set for each heater by adding the delay circuit 13, so that the following advantages are obtained. Since the instantaneous current decreases due to the decrease in the number of simultaneously driven heaters, the voltage drop in the _VH and GND wirings can be reduced. In the ink jet head, when adjacent heaters are simultaneously driven, a thermal problem such as fluid crosstalk or a rise in temperature may occur. Therefore, it is possible to provide a delay so that the adjacent heaters are not simultaneously driven.

In this embodiment, the delay circuit for arbitrarily shifting the drive timing is built in the heater board 1003. However, the same effect can be obtained by taking out a plurality of strobe terminals.

Further, in this embodiment, by taking out the output for cascade connection, it is possible to drive a plurality of heater boards by a data input signal necessary to drive one heater board (see FIG. 1). 15 to FIG. 17).

FIG. 14 shows an example in which the electric connection of FIG. 13 is arranged on a heater board 1003. 1005
Is a discharge heater, 1004 is a _DH wiring, 1015, 10
Reference numeral 16 denotes a transistor array unit, 1017 denotes a GND wiring, and 14 denotes a logic circuit unit. Signal input units 1 to 8 and signal output units 9 to 12 and 22 and 23 are formed as pads.

FIG. 15 shows the heater board 1003 of FIG.
2 shows how the signals of the line heads are cascaded by the electrical connection means 24 such as a flexible cable. In this embodiment, a line head is realized by using a staggered heater board. FIG.
A head unit 25 using the connected heater board is shown, and FIG. 17 shows a line recording apparatus using the head unit 25. Here, reference numeral 1004 denotes an input pad for an electric signal, and this signal is connected to all the heater boards by cascade connection. Reference numeral 1002 denotes an ink ejection orifice. In the present embodiment, the orifice has a staggered arrangement corresponding to the arrangement of the heater boards. FIG.
In 201A and 201B are rollers as conveying means provided for clamping conveying the recording medium R in a sub-scanning direction V _S. Reference numeral 200 denotes an ejection recovery unit, which is configured to face the recording head unit 25 in place of the recording medium R in the ejection recovery processing, and has a cap, an ink absorber,
The head in FIG. 17 including the wiping blade and the like has a staggered orifice arrangement by cascade connection.
The heaters for the line width may be arranged in one heater board 1003.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one driving vibration that gives a rapid temperature rise exceeding the nucleate boiling corresponding to the recorded information to the electrothermal transducer arranged corresponding to the sheet or liquid path in which , Heat energy is generated in the electrothermal transducer, and the film is boiled on the heat-acting surface of the recording head.
As a result, air bubbles in the liquid (ink) can be formed in one-to-one correspondence with the drive signal, which is effective. The growth of this bubble,
The liquid (ink) is discharged through the discharge opening by contraction to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. Examples of the drive signal in the form of a pulse include those described in U.S. Pat.
Suitable are those described in US Pat. No. 45,262. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat.
A configuration using the specification of Japanese Patent No. 459600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication (Kokai) No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing pressure waves of thermal energy. The present invention is effective even if the configuration is based on Japanese Patent Application Laid-Open No. 138461/1984, which discloses a configuration in which is adapted to a discharge unit.

Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, a combination of a plurality of recording heads as disclosed in the above-mentioned specification is used. Either a configuration that satisfies the length or a configuration as one integrally formed recording head may be used, but the present invention can more effectively exert the above-described effects.

In addition, the print head is exchangeable with a print head of a chip type, which can be electrically connected to the main body of the apparatus or supplied with ink from the main body of the apparatus, or is integrated with the print head itself. The present invention is also effective when a cartridge-type recording head provided in a fixed manner is used.

In the present invention, it is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like, which are provided as components of the printing apparatus, since the effects of the present invention can be further stabilized. Specifically, preheating of the recording head by a caving unit, a cleaning unit, a pressurizing or suctioning unit, an electrothermal converter, another heating element, or a combination thereof is performed. It is also effective to perform a preliminary ejection mode in which ejection is performed separately from the means and printing in order to perform stable printing.

Further, the printing mode of the printing apparatus is not limited to the printing mode of only the mainstream color such as black, and may be a single-color printing head or a combination of a plurality of printing heads. The present invention is extremely effective for an apparatus provided with at least one of full colors by color mixing.

[0039]

As described above, the discharge heater, the functional element, the integrated circuit for selectively driving the functional element in accordance with the serial image data, and the electrical contact with the outside are formed on the same substrate. Also, even in a high-density multi-nozzle, electric wiring does not become complicated. As a result, the number of contacts is small, so that the head becomes compact and the reliability is improved. In addition, mounting becomes easy, which leads to cost reduction.

Particularly, in the case of a head that can be replaced by the user, the effect on the reliability at the time of space saving / removing is large.

[Brief description of the drawings]

FIG. 1 is an embodiment of the present invention and is an electrical connection diagram on a heater board.

FIG. 2 is a timing chart showing the operation of the circuit of FIG.

FIG. 3 is a layout diagram on a heater board of the circuit of FIG. 1;

FIG. 4 is a configuration diagram of a recording head to which the present invention can be applied.

FIG. 5 is a sectional view of the vicinity of the nozzle in FIG. 4;

FIG. 6 is a sectional view showing the ejection state of the head of FIG. 4;

FIG. 7 is a sectional configuration diagram of the heater board shown in FIG. 3;

FIG. 8 is a recording apparatus to which the head of the present invention can be applied.

FIG. 9 is a layout diagram of a conventional head on a heater board.

FIG. 10 is an electrical connection diagram on a heater board of a conventional head.

FIG. 11 is an electrical connection diagram on a heater board of a conventional head.

FIG. 12 is an embodiment of the present invention and is an electrical connection diagram on a heater board.

FIG. 13 is a timing chart showing the operation of the circuit of FIG.

FIG. 14 is a layout diagram of the circuit of FIG. 12 on a heater board.

FIG. 15 is a diagram in which the heater boards of FIG. 14 are cascaded.

FIG. 16 is a view in which the heater board of FIG. 15 is in the form of a head.

FIG. 17 is a diagram in which the head of FIG. 16 is mounted on a line printer.

[Explanation of symbols]

V _H 2 GND 3 strobe fourth latch 5 serial data 6 clock 7 logic supply 8 enable 13 delay circuit 1005 discharge heaters 1015 first column transistor 1016 second column transistor 1023 logic gates logic 1024 latches for applying a voltage V _H in 1 ejection heater Circuit 1025 Shift register circuit

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Ishinaga 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Kimiyuki Hayashizaki 3-30-2 Shimomaruko, Ota-ku, Tokyo (56) References JP-A-3-15556 (JP, A) JP-A-58-36456 (JP, A) JP-A-2-281973 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) B41J 2/05 B41J 2/335-2/345

Claims (5)

(57) [Claims] 1. An arrangement for discharging ink from a discharge port.
A plurality of heating elements which are column output, and functional elements for selectively driving the electrically connected to the heat generating resistive element the heating resistance element, as a parallel signal received serial image data to the functional element and a integrated circuit,
An ink jet recording head in which a plurality of semiconductor substrates on which these heat generating resistance elements, functional elements, and integrated circuits are formed are arranged, wherein the integrated circuit outputs the received serial image data to the functional elements as parallel signals. A circuit for serially outputting image data to the semiconductor substrate arranged adjacent to the semiconductor substrate, wherein the semiconductor substrate has a signal input unit for receiving serial image data from the outside and supplying the serial image data to the integrated circuit; And a signal output unit for outputting serial image data output from the printer to the adjacently disposed substrate. 2. The ink-jet apparatus according to claim 1, wherein a delay circuit for adjusting a drive timing of each of the heating resistance elements is provided between the integrated circuit and the functional element on the substrate. Recording head. 3. The ink jet recording head according to claim 1, wherein the number of the heating resistance elements is 16 or more. Wherein said adjacent arranged the ink jet recording head according to claim 1 connected directly by the signal output section of the semiconductor substrate and the signal input section and the electrical connection means. 5. An ink jet recording apparatus comprising: the ink jet recording head according to claim 1; and conveying means for conveying a recording medium receiving ink ejected by the ink jet recording head.