JPH05229111A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To obtain a simple and small-size substrate and a small-size and low-cost device by providing a control means dividing recording information into blocks by the number of division drive signals and successively receiving the information per block under control. CONSTITUTION:Recording information (dot data) per 8 serial data signals SD is received by a shift register 6 on a clock signal SCK to be converted to parallel signals. Each of the dot data is stored in 8 latches 5 on a latch signal LA. On the other hand, a clock signal EDK is constantly inputted to a shift register 3. When the dot data is latched, division signals are outputted on a division drive signal generating input signal EIN for one period of the clock signal ECK. In a division drive control part 4, a group to which the inputted 8 dot data should be outputted is selected, for example, out of 1st to 5th groups by the division signals. The data are outputted to a head drive part 2 on a printing permitting signal ENB to be printed per group. After printing, the shift register 6 and the latch 5 are cleared.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet recording device.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording apparatus has been used in which a heating element as a discharge energy generating element is provided in a discharge member such as a nozzle and the discharge members are aligned.

That is, by energizing a heating element (hereinafter referred to as a heater) provided in a fine nozzle for ejecting ink, the heating element is caused to generate heat, and a rapid volume change occurs when the ink around the heater is heated or bubbled. Is used to perform recording by ejecting ink droplets from the ejection port, and there is one having a head in which a large number of nozzles are arranged and arranged in a predetermined direction.

In such an ink jet recording apparatus,
In general, a divided drive system has been adopted in which nozzles are divided into groups of a predetermined number and the heaters are driven in each group. This is an effective method for downsizing the power source for driving the head and the power source member such as the flexible cable for the power source connector.

Further, the ink jet power supply should have a very small fluctuation in voltage value in order to perform stable ejection in consideration of the characteristics of the heater and ink.
Since it is not desirable to increase the capacity of the power supply because it requires fine adjustment of the voltage value, the above method was effective in avoiding this.

A conventional example will be described below with reference to the drawings. FIG. 6 is a block diagram of a conventional inkjet recording apparatus, and FIG. 7 is a timing chart showing the operation timing of this conventional example. In FIG. 6, reference numeral 1 denotes an inkjet head unit, which has, for example, 40 nozzles, and these nozzles are divided into five groups from a first group to a fifth group with eight nozzles as one group.
During recording, each of these groups is sequentially driven in group units. Reference numeral 2 denotes a head drive unit having a head drive element provided corresponding to each of the nozzles, and the head drive element is an NPN-type transistor in Darlington connection. 3 is a shift register (S
R), and the ECK signal and EI as shown in FIG.
By the N signal, any one of the output signals Q _A to Q _E corresponding to each group is sequentially output during one cycle of the ECK signal.

Reference numeral 4 denotes a control unit for controlling the head drive unit 2, which has an AND gate corresponding to the heater provided in each nozzle. Each AND gate has three inputs, the first input is a drive control signal from the division control unit, and the second input is a serially input 40 dot data (Dot Data) signal (SD signal) from a CPU or the like. )
The third input receives a print permission signal (ENB signal), and controls which of the first to fifth groups the Dot Data is output to print when the print permission is given.

For example, the AND gate 4 corresponding to the first group has a drive control signal Q _A and a recording signal Dot Data.
# 1, # 6, # 11, # 16, # 21, # 26, # 3
AND gate 4 corresponding to the second group outputs signals Q _B and # 2, # 7, # 1.
The AND gate 4 corresponding to the third group outputs any of the signals Q2, # 17, # 22, # 27, # 32, and # 37.
_C and # 3, # 8, # 13, # 18, # 23, # 28, #
33, # 38, AND gate 4 corresponding to the fourth group outputs signals Q _D and # 4, # 9, # 14, # 1.
Any one of 9, # 24, # 29, # 34, and # 39 is supplied to the AND gate 4 corresponding to the fifth group by the signals Q _E and #.
5, # 10, # 15, # 20, # 25, # 30, # 3
Accept any one of # 5 and # 40. Reference numeral 5 is a latch for temporarily recording each Dot Data output from the shift register 3.

[0009]

As described above, in the conventional ink jet recording apparatus, the divided driving method in which the nozzles are divided into groups by a predetermined number and the driving is performed in each group is a dot data input by serial transmission.
shift register for converting a into parallel data corresponding to each nozzle, and each Do output from the shift register.
There is a problem in that latches for temporarily storing t Data are required for the number of nozzles of the inkjet head unit.

If the number of nozzles is increased as described above,
The shift register and the latch must be prepared by that amount, and there is a problem that the circuit configuration becomes complicated and large-scaled.

Further, from the above, there is a problem that when the circuit board and the apparatus body are miniaturized due to the expansion of the circuit, in other words, the size of the circuit board is reduced, the pitch of the circuit board pattern is increased and the number of ICs is increased. It was

The present invention has been made to solve the above-mentioned problems, and the number of shift registers and latches is greatly reduced, the circuit itself is simplified, and the size and cost of the device are reduced accordingly. The purpose is to enable.

[0013]

For this reason, in claim 1 of the present invention, there is provided an ink jet drive system in which the ink ejection timing is divided into a predetermined number of groups and each group is sequentially driven at a predetermined timing. In an ink jet recording apparatus, an ink jet recording apparatus having a control means for dividing recording information into blocks according to the number of divided driving signals and controlling so as to sequentially take in each block solves the above problems and achieves the above object. It is what

Further, according to a second aspect of the present invention, the recording head is provided for each of a plurality of ejecting sections for ejecting ink and the corresponding ejecting sections, and causes the ink to undergo a state change due to heat, thereby changing the state. The ink jet recording apparatus according to claim 1, further comprising: a thermal energy generating unit that ejects ink from the ejection unit to form flying droplets based on the above. To do.

[0015]

In the ink jet recording apparatus of the present invention, the control means controls the recording information to be divided into blocks according to the number of divided driving signals and to sequentially take in each of the blocks.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. First, an inkjet recording apparatus according to a first embodiment of the present invention will be described with reference to FIGS. 1 is a configuration diagram of a main part of an ink jet recording apparatus according to a first embodiment of the present invention, FIG. 2 is a timing diagram showing operation timing of the first embodiment, and FIG. 3 is a circuit diagram of a division drive control unit of FIG. Is. In the figure, the same reference numerals as those of the conventional example indicate the same or corresponding parts, and the description will be partially repeated.

In the first embodiment, the division drive signal as the drive means is used as a select signal for outputting Dot Data, so that the data input by serial transmission is converted into parallel Dot Data corresponding to each nozzle. The number of shift registers 6 for conversion and the number of latches 5 for temporarily storing each Dot Data output from the shift register 6 are respectively n = total number of nozzles / division driving number, that is, one group grouped by division driving. It is composed of shift registers and latches corresponding to the number of nozzles.

A detailed description will be given below with reference to FIGS. 1 to 3. 1 to 3, reference numeral 1 denotes an inkjet head unit having 40 nozzles, and a head drive voltage V _H is supplied to the heater in each nozzle.
Reference numeral 2 denotes a head drive unit having a head drive element provided corresponding to each nozzle. Reference numeral 3 denotes a shift register that sequentially generates divided signals for performing divided driving. Here, as the head drive element, an NPN-type transistor in Darlington connection is used, and each element is divided into 5 groups in units of 8 elements (8 nozzles) by a division signal from the shift register 3. The first group is # 1, # 6, # 11, # 21, # 26, # 31, # 36.
In each element (nozzle) of, the second group is #
2, # 7, # 12, # 17, # 22, # 27, # 32,
In each element of # 37, the third group is # 3, #
8, # 13, # 18, # 23, # 28, # 33, # 38
In each element of, the fourth group is # 4, # 9, #
In each element of 14, # 19, # 24, # 29, # 34, and # 39, the fifth group includes # 5, # 10, and # 1.
5, # 20, # 25, # 30, # 35, and # 40.

Reference numeral 4 is a divisional drive control unit, which receives the input 8
One of the Dot Data is selected by the division signal from the shift register 3 to which of the first to fifth groups the data is to be output, and is output to the head drive unit 2 by the print enable signal (ENB signal), and 40 Input AND gates are connected for each group. Then, in the first embodiment, as shown in FIG. 3, the input of Dot Data of the leading AND gate of each group is commonly connected to Dot Data 1 and is connected so as to select a group by a division signal. Reference numeral 6 denotes a shift register that outputs the recording information serially transmitted from a memory or the like in parallel in units of 8, and 5 latches each of the 8 Dot Data signals output from the shift register 6 to provide a division drive control unit. 4 is a latch for supplying the data to the memory.

Next, the operation of the first embodiment will be described with reference to FIG. FIG. 2 shows the operation timing of FIG. First, recording information (Do
t Data) is input to the shift register 6 in units of eight. The shift register 6 sends this Dot Data to the SC
The K signal is sequentially taken in and converted into a parallel signal. After this, each Dot Dat is changed by the latch signal (LA signal).
a is temporarily stored in eight latches.

On the other hand, the ECK signal is always input to the shift register 3, and when the Dot Data is latched, the divided signal Q _A is output by the EIN signal only for one cycle of the ECK signal. This makes Dot Dat
a is # 1, # 6 of the division control unit 4 to which Q _A is connected.
The signals are input to # 11, # 16, # 21, # 26, # 31, and # 36, respectively, and are printed by the print permission signal (ENB signal). After printing, the S / L CLR signal clears the shift register 6 and the latch 5, and waits for Dot Data input.

Then, the next eight Dot Data are # 2 of the division control unit 4 by the output Q _B of the shift register 3.
# 7, # 12, # 17, # 22, # 27, # 32, # 3
It is output to 7 and printed by the ENB signal. After that, Dot Data is output in units of 8 by Q _C , Q _D , and Q _E to the gates of the third to fifth groups to perform printing.
When the printing of the fifth group is completed, the SCLR signal is output, the shift register 3 is cleared, and printing is performed again in units of eight from the first group by the division signal Q _A again.
That is, according to the first embodiment, the drive of the inkjet head unit is grouped by using the divided signals of Q _A to Q _E which are the outputs of the shift register 3, and printing is performed for each group. Therefore, the shift of the Dot Data input section is performed. The number of registers and latches can be significantly reduced, the substrate can be simplified and downsized, the device can be downsized, and the cost can be reduced, and the advantages of the split drive method can be maximized.

Next, an ink jet recording apparatus according to the second embodiment of the present invention will be described with reference to FIGS.
The second embodiment relates to a division drive system of a color ink jet recording apparatus. FIG. 4 is a block diagram of an ink jet recording apparatus according to the second embodiment of the present invention, and FIG.
It is a timing diagram which shows the operation timing of an Example. In FIG. 4, reference numeral 1 denotes an inkjet head unit having 64 nozzles, which is composed of four head units each for a cyan head, a magenta head, a yellow head, and a black head. For the heater, drive voltages V _HC , V _HM ,
V _HY and V _HK are supplied respectively.

Reference numeral 3 denotes a shift register (SR) that sequentially generates eight division signals for performing division driving, and is similarly connected to each head. Here, as the head drive element, an NPN type transistor in Darlington connection is used, and each element in each head is divided into 8 groups (8 nozzles) in units of 8 elements (8 nozzles) by the division drive signal from the shift register 3. Is divided into Of the eight groups, the first group is # 1, # 9,
Each element (nozzle) of # 17, # 25, # 33, # 41, # 49, and # 57 has a second group of # 2, # 10, and # 1.
In each element of 8, # 26, # 34, # 42, # 50, and # 58, the third group is # 3, # 11, # 19, # 27, #.
Each of the elements 35, # 43, # 51, and # 59 is also configured by a combination of eight elements (nozzles) in the following groups. Reference numeral 4 denotes a division drive control unit which selects which of the first to eighth groups of each head is to output the Dot Data by dividing the input eight Dot Data by a division signal from the shift register 3 and permits printing. A signal (ENB signal) is output to the head drive unit 2, and 64 3-input AND gates for each color (1 head) are connected for each group. 7 is 4
It is a decoder for selecting each color head,
The four color heads are sequentially switched by two signals of EADSEL0 and HEADSEL1. Reference numeral 8 is a buffer which controls output by the head select signal output from the decoder 7. Reference numeral 6 is a shift register (SR) for parallel-converting and outputting the recording information transmitted serially from a memory or the like in units of 8, and 5 is a signal of 8 Dot Data output from the shift register 6. Is a latch (LA) for latching each of them and supplying them to the split drive control unit 4.

Next, the operation timing of the second embodiment will be described with reference to FIG. FIG. 5 shows the operation timing of FIG. In FIG. 5, first, recording information (Dot Data) which is an SD signal is input from the memory or the like to the shift register 6 (FIG. 4) in units of eight. The shift register 6 sequentially takes in this Dot Data by the SCK signal and converts it into a parallel signal. After this, the latch signal (L
Each Dot Data is temporarily stored in the eight latches 5 by the A signal). Next, 8 D's stored in latch 5
In order to determine which head is used to print ot Data, the heads are sequentially selected by two signals of HEADSEL0 and HEADSEL1, and the buffer 8 corresponding to each of the eight heads selected by this signal is selected. Output control is performed, and Dot Data is output from the buffer 8 corresponding to the selected head. For example, in FIG.
Then, both HEADSEL0 and HEADSEL1 are "Lo.
If the state is the w "state and the cyan head is selected in this state, it is transferred to the buffer 8 corresponding to the cyan head.

Next, the Dot D input to the buffer 8
ata is assigned to any one of the first to eighth groups of the cyan head by the division drive signal obtained from the shift register 3 according to the ECK signal and the EIN signal.
Whether to output t Data is selected. Here, first, the division drive signal Q _A is output, and the first group is selected by Q _A , and # 1, # 9, #
It is output to 17, # 25, # 33, # 41, # 49, and # 57, and is output to the cyan head in response to the print permission signal (ENB signal). After printing, the shift register 6 and the latch 5 are cleared by the S / L CLR signal, and the next data is awaited.

After that, Dot Da input in units of 8
The ta-divided drive signals Q _B to Q _H sequentially select the second to eighth groups for printing. And
By the division drive signal Q _H , 64 Dot Data of the cyan head are printed when the printing of the 8th group is completed.
Printing of (one line of head unit) is completed, and then H
The signals of EADSEL0 and HEADSEL1 are "Lo.
When it becomes w "or" Hi ", the magenta head is selected, and the first division driving signals Q _A to Q _H
Or, the eighth group is sequentially selected and printing is performed similarly.

That is, according to this example, the drive of the ink jet unit is grouped by utilizing the division drive signals of Q _A to Q _H which are the outputs of the shift register 3, and the drive is performed for each group, and the decoder 7 is used. Select the head to be used and print with Dot Dat.
The shift register 6 and the latch 5 in the input part of a can be significantly reduced, and the board can be simplified and downsized.
As a result, it is possible to obtain sufficient effects in downsizing the device and reducing costs. Further, regarding the printing speed, it is possible to cope with the decrease in speed by increasing the clock signals shown in FIG.

The present invention brings excellent effects particularly in a recording head and a recording apparatus of a system which utilizes thermal energy among the ink jet recording systems.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
Although it is applicable to any of the continuous type, in particular, in the case of the on-demand type, it is arranged corresponding to the sheet or the liquid path where the liquid (ink) is held, and the electrothermal converter, By applying at least one drive signal that corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal converter, and the film is boiled on the heat acting surface of the recording head. As a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal, which is effective. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. This drive signal pulse shape is more preferable because the growth and shrinkage of the bubbles are immediately and appropriately performed, so that the ejection of the liquid (ink) having excellent responsiveness can be achieved. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. still,
US Patent No. 4 of the invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification of No. 313124 are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the straight liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. The present invention also includes a configuration using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose a configuration in which the heat acting portion is arranged in a bending region. In addition, for multiple electrothermal converters,
Japanese Unexamined Patent Publication No. 123670/1984, which discloses a configuration in which a common slit is used as the discharge portion of the electrothermal converter, and Japanese Patent Laid-Open No. Sho-62-58, which discloses a configuration in which an opening for absorbing a pressure wave of thermal energy is associated with the discharge portion. The present invention is also effective as a configuration based on 1983, No. 138461.

[0032]

As described above, by utilizing the divided drive signal, which is the ink jet head unit driving means in the present invention, as the select signal for controlling the dot data output which is the record information, the dot data input in the serial format is used. Of each dot (Dot Data) output from the shift register for converting each pixel (nozzle) into parallel Dot Data
By dividing the number of latches that temporarily store Data into groups, each element is grouped by division driving, and by configuring the number of shift registers and latches by the number of elements (number of nozzles) that make up the group, the number of shift registers and latches can be reduced. There is an effect that it can be significantly reduced, the circuit itself can be simplified, and the size and cost of the device can be reduced accordingly.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of an inkjet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a timing chart showing the operation timing of the first embodiment.

FIG. 3 is a circuit diagram of a division drive control unit in FIG.

FIG. 4 is a configuration diagram of an ink jet recording apparatus that is a second embodiment of the present invention.

FIG. 5 is a timing chart showing the operation timing of the second embodiment.

FIG. 6 is a configuration diagram of a conventional inkjet recording apparatus.

FIG. 7 is a timing chart showing the operation timing of a conventional example.

[Explanation of symbols]

1 Inkjet head unit 2 Head drive unit 3 Divided drive signal generation shift register 4 Divided drive control unit 5 Latch 6 Data input shift register 7 Decoder (or selector) 8 Buffer SCK, ECK Clock signal SD Serial data signal LA Latch signal EIN Divisional driving signal without input signal Q _a generator Q _H head unit select signal S / L CLR, SCLR shift register / latch clear signal ENB print permission signal is noted that the same reference characters denote the same also corresponding parts.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI technical display location 9211-2C B41J 3/10 101 F (72) Inventor Jun Asuwa 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 Canon Inc.

Claims (2)

[Claims] 1. An ink jet recording apparatus having an ink jet drive system in which ink ejection timing of a recording head is divided into a predetermined number of groups, and each group is sequentially driven at a predetermined timing. An ink jet recording apparatus comprising a control unit for controlling to block and sequentially take in each block. 2. The recording head is provided for each of a plurality of ejecting sections for ejecting ink, and the corresponding ejecting section, and causes the ink to undergo a state change due to heat, and the ink is ejected from the ejecting section based on the state change. The inkjet recording apparatus according to claim 1, further comprising: a thermal energy generating unit that discharges the droplets to form flying droplets.