JP3554003B2 - Ink jet recording device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to an ink jet recording apparatus that records an image by discharging ink droplets on a recording material.
[0002]
[Prior art]
Conventionally, various recording apparatuses for performing recording on a recording medium such as paper and OHP sheets have been proposed. Among them, an ink jet recording apparatus ejects ink directly from a recording head onto recording paper. Attention has been paid to a recording apparatus having advantages such as low running cost and quiet recording operation.
[0003]
As a method of detecting that the ink amount has decreased in such an ink jet recording apparatus, a predetermined pattern, for example, a black mark is printed on the rear end of the recording paper, and the absence of the ink is detected by detecting the presence or absence of the mark. A method has been proposed. This method is an effective method because it is possible to detect the absence of ink without adding a special component to the recording head.
[0004]
On the other hand, in the ink jet recording apparatus, since it takes a little time for the ink to dry, the paper conveyance path from the recording head to the discharge stack section is intentionally lengthened, and There is a case where the ink is dried and then discharged. However, in this case, the printed recording paper cannot be nipped by the rollers or the like, so the conveyance tends to be unstable.Therefore, a jam sensor that detects that the recording paper has passed reliably should be used just in case. Usually, the reliability of the conveyance of the recording paper is ensured by the provision. With such a configuration, as a result, the above-described black mark sensor and the jam sensor are provided in the recording and discharging section of the apparatus.
[0005]
[Problems to be solved by the invention]
However, in the case of the above-described configuration, two sensors are required, so that the configuration of the device for arrangement and wiring is complicated, and there is a disadvantage that the cost is increased.
[0006]
Further, since the black mark is not originally required by the user, the presence of the black mark alone on the recording paper may give a sense of incongruity in terms of the aesthetic appearance of the printed matter.
[0007]
Furthermore, since the black mark is simply solid black, a relatively large amount of ink is consumed even in a small space, which is one of the factors that increase the running cost.
[0008]
The present invention has been made in view of the above points, and an object of the present invention is to provide an ink jet recording apparatus capable of simplifying the apparatus configuration and reducing the cost.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides an ink jet recording apparatus that records an image on a recording material using a recording head that ejects ink droplets according to image data, a conveying unit that conveys the recording material, A driving unit for driving the recording head to record a predetermined pattern at a predetermined position having a margin from the rear end of the recording material, the driving unit being a rear end of the recording material conveyed by the conveyance unit; A detecting unit provided at a position downstream of the recording position of the recording head in the conveying direction of the recording material and capable of detecting the predetermined pattern recorded by the driving unit, and a position facing the detecting unit. The predetermined pattern after recording the predetermined pattern at the predetermined position on the recording material by the driving unit after recording the image on the recording material; In the operation of discharging the recording material after transporting the recording material so as to face the detection position by the detection unit, the detection unit may be configured to control the recording position of the predetermined pattern, the margin, and the state after the recording material is discharged. Detection control means for controlling to perform detection by the detection means at a position opposed to each of the black members; first data obtained corresponding to the predetermined pattern under control of the detection control means; When each of the second data obtained correspondingly and the third data obtained corresponding to the black member is obtained by the detection result of the detecting means, it is determined that there is ink, and the above-described first data is excluded. When the second data and the second data are obtained from the detection result, a determination means for determining that there is no ink, and a detection of the detection means under the control of the detection control means. Control means for controlling the operation of the transport means, determining that there is an abnormality in the transport of the recording material by the transport means if the determination means does not determine whether there is ink or not, according to the result. It is characterized by.
[0010]
[Action]
According to the present invention, the presence / absence of the ink is determined by detecting the predetermined pattern recorded on the recording material at the predetermined position by the detecting means. Further, the detection means is also used to determine the conveyance error of the recording material.
[0011]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view showing a facsimile apparatus to which the present invention is applied. In FIG. 1, A is a reading unit that optically reads a document, B is a recording unit that is an ink jet recording device, and C is a recording paper cassette and a recording sheet that is a cut sheet loaded thereon is separated and supplied to the recording unit. Paper feed unit.
[0012]
In this figure, the flow of the recording paper will be briefly described first. A series of recording paper transport paths are indicated by an arrow G. First, the recording paper 12 loaded on the recording paper cassette 50 is picked up by a paper feed roller 51 and a separation claw 52 and transported by the transport roller 5 to form a recording unit. Sent to. In the recording unit, recording is performed by reciprocating the recording head 1 in a direction perpendicular to the paper surface and performing main scanning. After the recording head 1 is conveyed in the apparatus by a certain distance, the recording head 1 is discharged and stacked on a discharge stacker 53 by a discharge roller 9. You. A photo sensor 13 is arranged on the axis of the paper discharge roller 9, and is configured to detect the absence of ink in the recording head and a recording paper jam near the paper discharge roller by this sensor.
[0013]
Next, the configuration of the recording unit of this embodiment will be described in detail with reference to FIG. In FIG. 2, reference numeral 1 denotes a recording head. In this embodiment, an ink tank is incorporated, and a cartridge type ink jet recording head which can be replaced with a new recording head when the ink runs out is mounted.
[0014]
The recording head 1 used in the present embodiment is an inkjet recording head, has a resolution of 360 DPI, has 64 nozzles, and has a film boiling generated in the ink due to heat generated by an electrothermal transducer provided in the nozzle. The ink is ejected from the ejection port at the tip of the nozzle by the pressure.
[0015]
A carriage 2 reciprocates in a direction perpendicular to the conveying direction (sub-scanning direction) of the recording paper 12, that is, in the main scanning direction while holding the recording head 1 with high accuracy. The guide rod 11 and the abutting portion 2 a And is slidably held. The reciprocation of the carriage 2 is performed by a pulley 4 and a timing belt 3 driven by a carriage motor 32, which will be described later. At this time, a print signal and electric power to be applied to the recording head 1 are controlled by an electric circuit of the main body by a flexible cable 7. Supplied by
[0016]
Reference numeral 15 denotes a cap functioning as an ink receiving means, which is provided in correspondence with a position (home position) where the carriage 2 is on standby, moves up and down as needed, and is closely attached to the recording head 1 when ascending. To prevent evaporation of ink and adhesion of dust.
[0017]
In this embodiment, in order to position the recording head 1 and the cap 15 so as to be relatively opposed to each other, a carriage home sensor 10 provided on the main body of the printing apparatus and a light shielding plate 2b provided on the carriage 2 are provided. Is used. The carriage home sensor 10 is composed of a transmission type photo interrupter. When the carriage 2 moves to the standby position, light transmitted from a part of the carriage home sensor 10 is blocked by the light shielding plate 2b. This is used to detect that the recording head 1 and the cap 15 are at positions relatively opposed to each other.
[0018]
The recording paper 12 is fed upward from the lower side in the figure, is bent horizontally by the transport rollers 5 and the paper guide 6, and is transported in the direction indicated by the arrow H (sub-scanning direction). The transport roller 5 and the paper discharge roller 9 are each driven by a drive system (not shown), and transport the recording paper 12 in the sub-scanning direction with high accuracy in conjunction with the reciprocation of the carriage 2 as necessary. Reference numeral 8 denotes a spur, which is made of a material having high water repellency, and comes into contact with the recording paper 12 only at the recording paper surface and at the peripheral portion having a blade-like shape. The recording paper 12 is configured to be guided and conveyed without affecting the image even if it comes into contact with unfixed ink on the recording paper immediately after printing. A photo sensor 13 is disposed on the axis of the paper discharge roller 9 and is a reflection type photo interrupter that optically detects the presence or absence of a predetermined pattern (black mark) printed on the recording paper. And paper jam can be determined from the output of the black mark and the white output of the recording paper. The photosensor used in the present embodiment uses a red LED as a light emitting element and a phototransistor as a light receiving element, and can determine whether a range having a diameter of 3 mm is white or black. The paper discharge roller 9 has a photo sensor opposing portion made of black rubber so that black output is obtained when there is no recording paper.
[0019]
FIG. 3 is a block diagram showing a schematic configuration of a main part of an electric circuit of the facsimile apparatus of the present embodiment. In FIG. 3, reference numeral 21 denotes a control unit for controlling the entire recording apparatus, which is used as a work area of the CPU 23 such as a microprocessor, a ROM 25 storing a control program of the CPU 23 and various data, and a work area of the CPU 23. It has a RAM 27 and the like for temporarily storing data.
[0020]
Reference numeral 28 denotes a head drive circuit for driving the recording head 1 to eject ink droplets, 29 denotes a carriage motor drive circuit for driving a carriage motor 32 which is a drive source for reciprocating the carriage 2, and 30 denotes a line. An image data input circuit for receiving image data sent through the device, demodulating the image data, and inputting the image data into the apparatus, 31 is an image memory for storing image data input from the image data input circuit 31, and 33 is a photo memory. A detection circuit 34 converts the output current from the sensor 13 into a voltage having a proportional magnitude and outputs the voltage. The detection circuit 34 compares the output voltage from the detection circuit 33 with a predetermined threshold voltage, and outputs the comparison result to the control unit 21. A comparator 35 is a transport motor drive circuit for driving a transport motor 36 which is a drive source of the transport roller 5 and the discharge roller 9, and 37 is a pickup for recording paper. A clutch for transmitting the driving force of the conveyance motor 36 to a paper feed roller 51 for cleaning, an alarm 38 having a display unit 39 for displaying light when ink out is detected and a display unit 40 for displaying light when recording paper jam is detected. Circuit.
[0021]
Next, a sequence of ink absence detection and jam detection in the present embodiment will be described with reference to the flowchart of FIG. A program corresponding to this flowchart is stored in the ROM 25, and the CPU 23 performs control according to this program. First, the transport motor 36 and the clutch 37 are operated, the recording paper is picked up, the image data is read out from the image memory 31, an image for one page is recorded (step S1), and a black mark is printed on the rear end of the recording paper. (Step S2). The black mark is printed with a simple black solid dot matrix, and is recorded in a shape as shown in FIG. 5 with a margin between the trailing end of the recording paper and the white output of the recording paper for discrimination. The recording paper is conveyed until a black mark comes to the position of the photo sensor 13 provided on the axis of the paper discharge roller 9, which is the last part of the paper conveyance path (step S3). Then, at the timing when the black mark reaches the position of the photosensor 13, the output data (white or black) of the photosensor 13 is stored in the RAM 27 via the detection circuit 33 and the comparator 34 (step S4). Next, the recording paper is transported until a blank portion between the black mark and the trailing edge of the recording paper reaches the position of the photosensor 13 (step S5). Then, at the timing when the margin reaches the position of the photosensor 13, the output data (white or black) of this portion of the photosensor 13 is stored in the RAM 27 again (step S6). Further, the recording paper is conveyed until the recording paper is stacked on the paper discharge stacker 53, and the black surface of the paper discharge roller 9 is read by the photo sensor 13 at the timing when the recording paper is discharged to the paper discharge stacker 53. The output data is stored in the RAM 27 (step S7). Thereafter, referring to the data in the RAM 27, if the data is in black and white order, it is determined that the recording has been completed normally (step S8). Is turned on to start picking up the next sheet, and the same operation is repeated (step S10). If NO in step S8, if the order is white and black and white, it is determined that the black mark could not be printed because the ink has run out, and the display unit 39 is turned on to notify that there is no ink. For example, it is determined that the recording paper has not been properly conveyed for some reason and jammed or stopped, and the display unit 40 is turned on to notify that the recording paper conveyance path should be checked again (step S9). Thus, a series of recording operations is completed. However, as described above, since the photosensor 13 is provided at the end of the paper transport path on the axis of the paper discharge roller 9, the upstream side (that is, the entire paper transport path) is provided. A transport abnormality can be detected. For this reason, two functions of ink absence detection and jam detection can be realized with one photosensor.
[0022]
(Other embodiments)
The black mark in the above embodiment is a simple black solid rectangle as shown in FIG. 5, but when applied to a facsimile machine, it is convenient to print the page of the transmitted document, and this is shown in FIG. As described above, the page number of the document may be recorded by combining the black mark with the white characters.
[0023]
Further, in order to save ink for printing the black mark, the black mark is not a simple black solid, but the threshold value of the comparator 34 is corrected, and the dots are thinned out in a zigzag pattern of, for example, 75% or 50%. It is also possible to print in a matrix pattern.
[0024]
As described above, the arrangement position of the black mark is provided by providing a margin from the rear end of the recording paper, the position of the photo sensor is disposed on the paper discharge roller, and after the output signal of the photo sensor is determined. By picking up the next recording paper, the inkless sensor and the paper jam sensor can be combined into one, and the apparatus can be simplified, the cost can be reduced, and the reliability can be improved.
[0025]
In addition, by adding character information to the black mark, the user's uncomfortable feeling can be eliminated, and by recording the black mark in a dot matrix thinned out in a staggered manner, the ink consumption can be reduced and the running cost can be reduced. I can do it.
[0026]
Next, the principle of ejection of the recording head used as the recording means in the ink jet recording apparatus of the present embodiment will be described. A recording head section applied to an ink jet recording apparatus generally includes a fine liquid discharge port (orifice), a liquid path, an energy acting section provided in a part of the liquid path, and a liquid acting on the liquid in the acting section. An energy generating means for generating droplet forming energy is provided and is replaceable.
[0027]
As an energy generating means for generating such energy, one using an electromechanical transducer such as a piezo element, or irradiating an electromagnetic wave from a laser or the like, absorbing the liquid there to generate heat, Droplets are ejected and fly by the action of heat generation, and liquids are ejected by heating the liquid with an electrothermal converter. Among them, a recording head portion used in an ink jet recording method in which a liquid is discharged by thermal energy has a high density of liquid discharge ports (orifices) for discharging a recording droplet to form a flying droplet. Therefore, it is possible to record at a high resolution.
[0028]
In addition, a recording head using an electrothermal transducer as an energy generating means can easily be made compact as a whole as a recording head, and has made a remarkable improvement in technology and reliability in recent semiconductor fields. Technology and micromachining technology can be fully utilized, and it is easy to increase the length and the surface area (binary). It is possible to provide an inkjet recording head part with good productivity and low production cost.
[0029]
In general, an ink jet recording head manufactured using a semiconductor manufacturing process using an electrothermal converter as an energy generating means is provided with liquid paths corresponding to each ink discharge port, and the liquid path is provided for each liquid path. An electrothermal converter is provided as means for applying thermal energy to the liquid filling the path to discharge the liquid from the corresponding ink discharge port to form flying droplets. The liquid is supplied from a common liquid chamber communicating with the liquid. In addition, regarding the method of manufacturing the ink discharge unit, the present applicant has at least a solid layer for forming a liquid path on the first substrate, and an active energy ray-curable material layer used for forming at least a wall of the liquid path; After sequentially laminating the second substrate, a mask is laminated on the second substrate, and an active energy ray is irradiated from above the mask so that at least a wall of the liquid path of the active energy-ray curable material layer is removed. A method of forming at least a liquid path by curing as a constituent part and further removing an uncured part of the solid layer and the active energy ray-curable material layer from between the two substrates has been filed (see Japanese Patent Application Laid-Open No. 62-253457). ).
[0030]
FIG. 7 shows a schematic configuration of the above-described inkjet recording head unit. The recording head unit 101 has a hardened active energy having an electrothermal converter 103, an electrode 104, and a liquid path 110 formed on a substrate 102 as a first substrate through a semiconductor manufacturing process such as etching deposition and sputtering. -Consists of a line-curable material layer 210 and a top plate 106. Thus, in such a recording head unit 101, the recording liquid 112 is supplied from a liquid storage chamber (not shown) through the liquid supply pipe 107 into the common liquid chamber 108.
[0031]
Reference numeral 109 denotes a liquid supply pipe connector. The recording liquid 112 supplied to the common liquid chamber 108 is supplied to the liquid path 110 by a capillary phenomenon, and is stably held by forming a meniscus at the ink discharge port 111 at the front end of the liquid path. Then, when electricity is supplied to the electrothermal converter 103, the liquid on the electrothermal converter surface is heated, a bubbling phenomenon occurs due to film boiling, and droplets are ejected from the ink ejection ports 111 by the growth of the bubbles. With the above-described configuration, a multi-nozzle ink jet recording head can be formed with a high-density liquid passage pipe having a discharge port density of 360 to 400 dots / inch.
[0032]
A typical configuration and principle of an ink jet recording system for performing recording by forming flying droplets by using such thermal energy is described in, for example, US Pat. Nos. 4,723,129 and 4,740,796. Is preferably performed using the basic principle disclosed in US Pat. 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, it corresponds to a sheet or a liquid path holding a liquid (ink). Heat energy is generated in the electrothermal transducer by applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer disposed at a distance. This is effective because it causes film boiling on the heat-acting surface of the recording head, and as a result, bubbles in the liquid (ink) corresponding one-to-one with this drive signal can be formed. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. 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 the liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.
[0033]
As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.
[0034]
As the configuration of the recording head, in addition to the combination of the ejection port, the liquid path, and the electrothermal converter (the linear liquid flow path or the right-angled liquid flow path) as disclosed in the above-mentioned specifications, No. 4,558,333 and US Pat. No. 4,459,600, which disclose a configuration in which is disposed in a bending region.
[0035]
In addition, Japanese Unexamined Patent Publication No. 59-123670 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. May be configured based on JP-A-59-138461, which discloses a configuration in which the image forming apparatus corresponds to a discharge unit.
[0036]
In addition, a replaceable chip-type recording head that can be electrically connected to the device main body and supplied with ink from the device main body by being attached to the device main body, or ink that is integrated with the recording head itself A cartridge type recording head provided with a tank may be used.
[0037]
Further, it is preferable to add recovery means, preliminary auxiliary means, and the like to the recording head because the effects of the present invention can be further stabilized. Specific examples include capping means for the recording head, cleaning means, pressurizing or sucking means, preheating means using an electrothermal transducer or another heating element or a combination thereof, and recording. It is also effective to perform a preliminary ejection mode for performing another ejection to perform stable printing.
[0038]
Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, and the recording head may be integrally formed or a combination of plural recording heads. Alternatively, the apparatus may be provided with at least one of full colors by color mixing.
[0039]
In the embodiments of the present invention described above, the ink is described as a liquid.However, an ink that solidifies at room temperature or below, and that softens at room temperature or is a liquid, such as a liquid that is used when a use recording signal is applied. It is sufficient if the ink is in a liquid state.
[0040]
In addition, an ink that positively prevents temperature rise due to heat energy as energy for changing the state of the ink from a solid state to a liquid state, or solidifies in a standing state to prevent evaporation of the ink. In any case, the ink is liquefied by the application of the heat energy according to the recording signal, and the ink is ejected as a liquid ink, or the ink already solidifies when it reaches the recording medium. The use of an ink which liquefies for the first time by heat energy is also applicable to the present invention. In such a case, the ink is held in a liquid state or a solid state in the concave portions or through holes of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. In this case, a configuration may be adopted in which the electrothermal converter faces the electrothermal converter.
[0041]
【The invention's effect】
As described above, according to the present invention, the presence or absence of ink is determined according to the detection result of the detection unit that detects the predetermined pattern recorded at the predetermined position on the recording material, and the recording material conveyance abnormality is determined. In addition, the detection of the absence of ink and the detection of the conveyance error of the recording material can be performed by the common detection unit, so that the apparatus configuration can be simplified and the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a facsimile apparatus.
FIG. 2 is a perspective view illustrating a configuration of an inkjet recording unit.
FIG. 3 is a block diagram illustrating a configuration example of a control system of the inkjet recording unit.
FIG. 4 is a flowchart illustrating a sequence of detecting ink absence and recording paper jam.
FIG. 5 is a diagram showing an example of the shape of a black mark.
FIG. 6 is a diagram showing the shape of a black mark in another embodiment.
FIG. 7 is a perspective view illustrating a configuration of a recording head.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Recording head 2 Carriage 5 Conveyance roller 8 Spur 9 Discharge roller 12 Recording paper 13 Photosensor 21 Control part 23 CPU
32 Carriage motor 36 Transport motor 38 Alarm circuit

Claims (5)

In an inkjet recording apparatus that records an image on a recording material using a recording head that discharges ink droplets according to image data,
Conveying means for conveying the recording material,
A driving unit that drives the recording head to record a predetermined pattern at a predetermined position having a margin from the rear end of the recording material at a rear end of the recording material conveyed by the conveyance unit,
Of the recording apparatus main body, a downstream side in the transport direction of the recording material than the recording position by the recording head, a detecting section that is provided capable of detecting a position of the predetermined pattern recorded by said drive means,
A black member arranged at a position facing the detection means,
After the recording of the image on the recording material, after the recording of the predetermined pattern at the predetermined position on the recording material by the driving unit, the recording material is conveyed such that the predetermined pattern faces the detection position of the detection unit, and then recording is performed. In the operation of discharging the material, the detection unit performs the detection by the detection unit at a position facing the recording position of the predetermined pattern, the margin, and the black member after the recording material is discharged. Detection control means for controlling;
Under the control of the detection control means, the first data obtained corresponding to the predetermined pattern, the second data obtained corresponding to the margin, and the third data obtained corresponding to the black member are respectively When the detection result is obtained by the detection means, it is determined that there is ink, and when the second data excluding the first data and the second data are obtained from the detection result, it is determined that there is no ink. Determining means;
According to the detection result of the detection means under the control of the detection control means, if the discrimination means does not discriminate between the presence of ink and the absence of ink, it is determined that the conveyance of the recording material by the conveyance means is abnormal, Control means for controlling the operation of
An inkjet recording apparatus comprising: 2. The ink jet recording apparatus according to claim 1 , wherein the control unit controls the transport unit to feed the next recording material when the determination unit determines that there is ink. Further, a notifying means for notifying a recording material conveyance abnormality is provided,
It said control means is an ink jet recording apparatus according to claim 1 or 2, characterized in that operating the informing means when it is determined that there is an abnormality in the conveyance of the recording material. 2. The ink jet recording apparatus according to claim 1, wherein character information is added to the predetermined pattern. 2. The ink jet recording apparatus according to claim 1, wherein the predetermined pattern is a dot matrix pattern thinned out in a staggered manner.

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