JPH09131894A - Ink-jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording apparatus with high precision for judging the lack of ink which can read recording paper at proper sensitivity by optimizing amperage to be supplied to a light emission part in accordance with the deterioration of the emission part periodically every time when the lack of ink occurs. SOLUTION: Every time when the presence or absence of an ink tank is detected, that is, every time when the ink tank is replaced, the output level of reflected light received by a light receiving part 11b is sampled prescribed times by a CPU part 1, and amperage to be supplied to the emission part 11a is set/changed on the basis of the average of sampled output levels.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly to recording an ink end mark for determining ink shortage on a recording paper, and optically reading the ink end mark to determine ink shortage. The present invention relates to an inkjet recording device.

[0002]

2. Description of the Related Art Generally, a thermal printer, an ink jet recording apparatus, etc. are used as a means for printing on recording paper. With thermal recording paper used in thermal printers, when the roll-shaped thermal recording paper reaches a certain length before it runs out, the recording paper will be black-printed at a predetermined location in advance, and this black print density (black density) Is detected by the detection means, it is possible to determine whether the thermal recording paper is out of paper.

On the other hand, as a method of printing a mark on a recording paper to detect ink shortage, for example, Japanese Patent Laid-Open No. 2-221 is known.
A "data processing device" described in Japanese Patent No. 814 is known. This is one of the printing heads that conveys recording paper
A mark is printed at a predetermined position before the end of the page, and when the reading position of the photoelectric sensor and the printed position of the mark match, it is determined whether or not the mark is detected. Then, when no mark is detected, it is determined that the ink is out, the conveyance of the recording paper is stopped, and the print data in the memory is transferred to and stored in the large-capacity memory to output a blank recording paper. There is an advantage that it is possible to prevent waste of data and prevent loss of data.

As another apparatus for detecting ink shortage, there is an "ink jet recording apparatus" of Japanese Patent Application No. 5-196598 of the prior application. In this type, the light-emitting side of the photoelectric sensor irradiates light to the unprinted area of the recording paper, and the light-receiving side of the photoelectric sensor receives the reflected light from the recording paper. It is converted and converted from an analog value to a digital value by the A / D converter. Next, the voltage value converted into a digital value is sampled based on a predetermined sampling frequency. After the sampling is repeated a specified number of times, the average value α of the sampled voltage values is calculated, and the voltage ratio (α / β) to the voltage separation ability β of the A / D converter is calculated. Then, based on the calculated voltage ratio (α / β), the output level on the light receiving side is adjusted to an output level at which the non-printed portion and the printed portion of the recording paper can be normally discriminated.

As described above, since the output level of the photoelectric sensor (light receiving side) is adjusted based on the voltage ratio (α / β), the performance of the A / D converter can be sufficiently brought out and the photoelectric sensor can be obtained. It is possible to absorb variations in the reading performance due to the difference in sensitivity and to automate the adjustment of the output level.

However, the former "data processing device"
In that case, the ink is judged to be out depending on the presence or absence of the mark, but since the sensitivity of the photoelectric sensor was not taken into consideration, a photoelectric sensor with uneven sensitivity was used, and a photoelectric sensor with poor sensitivity was installed. In the case of such an apparatus, there is a problem in that the reflected light from the recording paper cannot be accurately read and accurate ink exhaustion determination cannot be performed.

In order to solve such a problem, in the case of a device provided with a photoelectric sensor having a variation in sensitivity, a semi-fixed resistor or the like is connected to the light receiving side of the photoelectric sensor to output the output level of the photoelectric sensor. It is known that the sensitivity of the photoelectric sensor is artificially adjusted by adjusting the semi-fixed resistor, etc. while investigating. There was a problem that it was necessary to be familiar with the above and adjustment was not easy.

Further, if there is a possibility that the photoelectric sensor has a cause of abnormality, the output level of the photoelectric sensor must be measured each time, which makes the adjustment more difficult. On the other hand, in the latter "ink jet recording apparatus", the output level of the photoelectric sensor on the light receiving side is adjusted. Therefore, when the amount of light irradiated on the recording paper is extremely short, Even if the output level is adjusted, there is a problem in that the recording paper cannot be read accurately because the absolute amount of light reflected from the recording paper is insufficient.

In order to solve such a problem, the present applicant has proposed the one described in Japanese Patent Application No. 6-95367. This is a light emitting unit that emits light according to the amount of supplied current, a light receiving unit that receives reflected light from the recording paper, and a sampling that samples the output level of the reflected light received by the light receiving unit a predetermined number of times. And a control unit that sets / changes the amount of current supplied to the light emitting unit based on the average value of the output levels sampled by the sampling unit.

According to this, it is possible to correct the amount of light emitted from the light receiving unit onto the recording paper in accordance with the variation and deterioration of the light emitting unit and the light receiving unit, and to read the recording paper with appropriate sensitivity. Therefore, the accuracy of determination of ink shortage can be improved.

[0011]

However, in such a conventional ink jet recording apparatus, since there is no mention of a specific time or method for setting / changing the amount of current supplied to the light emitting portion, If the amount of current supplied to the light emitting unit is not set / changed over a long period of time, the recording paper may be changed from the light emitting unit depending on variations or deterioration of the light emitting unit or the light receiving unit until the current amount is set / changed. The amount of light applied to the ink cannot be adjusted to an appropriate level, and the accuracy of the ink out determination cannot be sufficiently improved, and there is still room for improvement.

Therefore, according to the first aspect of the present invention, the amount of current supplied to the light emitting portion is set / changed each time the ink cartridge is replaced, so that the light emitting portion is periodically deteriorated each time ink runs out. An object of the present invention is to provide an ink jet recording apparatus with high accuracy of ink shortage determination, which can read the recording paper with appropriate sensitivity by optimizing the amount of current supplied to the light emitting unit according to the state. .

According to a second aspect of the present invention, each time the ejection port of the print head is cleaned, the amount of current supplied to the light emitting portion is optimized so as to follow the deterioration state of the light emitting portion. Even when applied to a small amount of inkjet recording device or a facsimile device mainly used for transmission, the inkjet recording device can read out the recording paper with appropriate sensitivity and has a high accuracy of ink exhaustion determination. Is intended to provide.

[0014]

According to the first aspect of the present invention,
In order to solve the above problems, a current supplied to an ink jet recording apparatus that irradiates an ink end mark printed on recording paper with light and detects the presence or absence of ink in an ink cartridge based on the output level of the reflected light. A light emitting unit that emits light according to the amount, a light receiving unit that receives reflected light from the recording paper, an ink cartridge detection unit that detects whether or not an ink cartridge is installed, and a reflected light received by the light receiving unit. When the ink cartridge detection unit detects that the ink cartridge is installed, the output unit supplies the light emitting unit based on the average value of the output levels sampled by the sampling unit. And a control unit that sets / changes the amount of current to be applied.

In this case, each time the presence or absence of the ink cartridge is detected, that is, each time the ink cartridge is replaced, the output level of the reflected light received by the light receiving section is sampled a predetermined number of times, and the sampled output level is sampled. The amount of current supplied to the light emitting unit is set / changed based on the average value of Therefore, the amount of current supplied to the light emitting section is set to an optimum value on a regular basis whenever the ink runs out, following the deterioration state of the light emitting section. As a result, the recording paper is always read with an appropriate sensitivity, and the accuracy of the ink exhaustion determination is improved.

In order to solve the above-mentioned problems, the invention according to claim 2 is the invention according to claim 1, wherein a cleaning section for cleaning the ejection port of the print head provided in the ink cartridge, and an ejection by the cleaning section. An operating unit for instructing to clean the mouth, and the controller controls the average value of the output levels sampled by the sampling unit when an instruction for cleaning is given by the operating unit. The amount of current supplied to the light emitting unit is set / changed based on the above.

In this case, each time the ejection port of the print head is cleaned, the amount of current supplied to the light emitting unit is optimized according to the deterioration state of the light emitting unit, and the current amount is set / changed in a short cycle. It Therefore, for example, in the case where it is applied to an inkjet recording apparatus that prints only image information with a low black ratio and consumes less ink, or a facsimile apparatus that is mainly used only for transmission and has few printing opportunities, etc. Also, the recording paper is read with appropriate sensitivity, and the accuracy of the ink exhaustion determination is improved.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 10 are system configuration diagrams of an ink jet recording apparatus according to the invention of claim 1 or 2, and show an example applied to a facsimile apparatus. First, the configuration will be described. 1 is a CPU (Central Processing)
Unit) and the CPU unit 1 is a ROM (not shown).
Based on a program and various data stored in (Read Only Memory), each unit of the inkjet recording device 4 is mainly controlled.

The memory unit 2 includes a ROM and a RAM (Random A
ccess Memory) or SRAM (Static Random Acce
ss Memory), the ROM stores a threshold value used for determining the ink exhaustion described later and controlling the switch unit 15, and the RAM or SRAM stores the setting of the switch unit 15 and the ink density detection unit 5 described later. The output value of is stored.

The display operation unit (operation unit) 3 is composed of a liquid crystal display panel, various operation keys and the like. When the ink runs out, the liquid crystal display panel makes various displays to warn the ink runs out. The display function for this warning may be a buzzer that emits an alarm sound, an LED, or the like. The various operation keys include a transmission start key, a shortening key, and the like, as well as operation switches for operating a cleaning device, which will be described later.

The ink jet recording apparatus 4 comprises a recording paper motor section 6, an ink cartridge driving section 7, an ink cartridge 8 and an ink cartridge detecting section 9 and is shown in FIG. In FIG. 2, the recording paper motor unit 6 is configured to convey the recording paper P in the forward direction or the reverse direction based on a command from the CPU unit 1.

The ink cartridge drive section 7 is based on a command from the CPU section 1 and is used as an ink tank 31Y, 31M, 31.
C and 31B are moved to the left and right to the printing position on the recording paper, and are composed of a carriage unit 21, a CR motor 22, a timing belt 23, an LF motor 24, and a conveyance roller 25. The ink cartridge 8 includes an ink tank 31B for black ink, an ink tank 31C for cyan ink, an ink tank 31M for magenta ink, an ink tank 31Y for yellow ink, and a print head 30 that store ink of each color inside. The print head 30 is mounted on the carriage unit 21, and in response to a command from the CPU unit 1, ink of each color sent from the ink tanks 31Y, 31M, 31C, 31B is output from an ink ejection port 30a corresponding to each color by a clock signal. An ink ball is ejected to form a color image on the recording paper P, and during this printing operation, an all-black or near-black ink-out determination mark (ink end mark) is printed on a predetermined portion of the recording paper.

Further, the print head 30 has a switch 32 for detecting whether or not the ink tanks 31Y, 31M, 31C and 31B of the respective colors are mounted on the print head 30, as shown in FIG. 3 (a). The switch 32 constitutes a part of the ink cartridge detection unit 9. FIG. 3B is a configuration diagram of the ink cartridge detection unit 9. The switch 32 is embedded in the mounting surface of the print head 30 at a position corresponding to each ink tank 31Y, and when each ink tank 31Y depresses the plunger of the switch 32, the switch is turned on.

Further, in the ink cartridge detecting section 9, the print head 30 and the facsimile apparatus main body are connected by the contacts P11 and P12, and the switch 32 on the print head 30 side and the fixed resistor 33, fixed resistor on the facsimile apparatus main body side. 3
4, composed of a buffer 35. The switch 32 is in an OFF state when the ink tank 31Y is not attached, and is in an ON state when the ink tank 31Y is attached. When the fixed resistor 33 and the fixed resistor 34 are connected by the switch 32, the fixed resistor 33 and the fixed resistor 34 divide the power supply voltage Vcc to set the input logic level to the buffer 35 to the high level state. The buffer 35 converts the output voltage of this circuit into a logic level and sends it to the CPU section 1. The CPU section 1 causes the ink tanks 31Y, 31M, when the switch 32 is switched from OFF to ON. 31
Judge that C and 31B have been exchanged.

The CPU section 1 periodically monitors the state of the switch 32 at regular intervals in consideration of the chattering of the switch 32. For example, each of the switches 32 is turned off and turned on four times in succession. (OFF → OFF → O
FF → OFF → ON → ON → ON → ON), it may be determined that the ink tanks 31Y, 31M, 31C, 31B have been replaced.

In this embodiment, the ink tank 31Y,
31M, 31C, 31B and print head 30 are separate bodies, but ink tanks 31Y, 31M, 31C, 31B and print head
30 may be one. In this case, the integrated ink tanks 31Y, 31M, 31C and 31B and the print head 30
Is mounted on the carriage unit 21, and the carriage unit
A switch 32 will be provided on 21.

A home position of the ink cartridge 8 is set on either one of the widthwise sides of the timing belt 23, and a cleaning device (cleaning unit) 26 is provided at this home position. The cleaning unit 26 includes an ink ejection port 30a of the print head 30.
It has a function of removing clogging and the like of the ejection port 30a by contacting with the nozzle and sucking ink from the ejection port 30a.

On the other hand, the ink density detecting section 5 includes the CPU section 1.
Irradiates the recording paper with light based on a command from
It has a function of receiving the reflected light from the recording paper and outputting a voltage value represented by a digital value according to the light amount of the reflected light. The photoelectric sensor 11 and the current-voltage conversion resistance unit (hereinafter, I / V conversion resistance) 12), A / D converter section 13, transistor
14, a switch unit 15, and a current limiting resistor 16.

The photoelectric sensor 11 is arranged at a position where the ink depletion judgment mark can be detected, and irradiates the recording paper with light by passing a current through the light emitting portion 11a, and the light reflected by the recording paper is received by the light receiving portion 11b. To receive light. The light emitting unit 11a is
The amount of light emission is determined according to the amount of current, and the light receiving unit 11b converts it into a current according to the amount of received light. I / V conversion resistor section 12
Converts the current (I) flowing through the light receiving portion 11b into a voltage (V) according to the reflected light from the recording paper P and supplies the voltage to the A / D converter portion 13. The A / D converter unit 13 has a voltage separation capability β, and A / D converts the voltage supplied from the I / V conversion resistor unit 12 from an analog value to a digital value at a sampling frequency based on an external clock (not shown). .

The transistor 14 is turned on / off based on a command from the CPU section 1, and controls whether or not to supply a current to the light emitting section 11a of the photoelectric sensor 11. The switch unit 15 is a CPU
SW1 and SW2 are turned on / off based on a command from the unit 1, and the amount of current flowing through the light emitting unit 11a is controlled. Current limiting resistor
The resistor Ra has resistors Ra, Rb, and Rc connected in parallel and controls the amount of current flowing through the light emitting unit 11a together with the switch unit 15. The resistance value and the number of resistors of the current limiting resistor 16 are arbitrarily set in a range that does not exceed the rating of the light emitting unit 11a in consideration of the external environment. Further, instead of connecting resistors in parallel and changing the combined resistance by the switch unit 15, the resistance value may be changed by using a volume or the like. In addition, VCC17 and GND18
Is a power supply voltage for applying a constant voltage to the ink density detecting device 5.

In this embodiment, the light emitting section 11a constitutes a light emitting section and the light receiving section 11b constitutes a light receiving section. Also,
The CPU unit 1, the current-voltage conversion resistance unit 12 and the A / D converter unit 13 form a sampling unit, and the CPU unit 1, the switch unit 15 and the current limiting resistor 16 form a control unit. FIG. 4 is a diagram showing marks printed on a recording paper by the inkjet recording apparatus of the present invention and sampling directions of the marks.

In FIG. 4, the recording paper P will be described assuming that the ink-jet recording apparatus 4 prints the ink-out judgment mark 41. First, when sampling the recording paper P, the recording paper P is conveyed in the recording paper conveyance direction.
Transport to 42. Next, when the sampling start position of the recording paper P reaches the reading position of the photoelectric sensor 11, the CPU unit 1
Turns on the transistor 14 to operate the photoelectric sensor 11.

Next, the CPU section 1 samples the output level of the photoelectric sensor 11 based on the sampling frequency. Since the recording paper P is conveyed in the recording paper conveyance direction 42, the recording paper P is sampled in the + l direction from the sampling start position as shown by the arrow 43. FIG. 5 shows an inkjet recording apparatus 4 of the present invention.
FIG. 6 is a diagram showing a connection state of the switch section 15 of FIG.

In FIG. 5, when the connection state is the a state, it indicates that both SW1 and SW2 of the switch section 15 are off, and when the connection state is the b state,
It is shown that SW1 of the switch unit 15 is off and SW2 is on, and when it is in the c state, SW1 and S
It shows that both W2 are in the ON state. FIG. 6 is a diagram showing the output level of the photoelectric sensor in each connection state when the same object is sampled by defining the connection state of the switch unit 15 as shown in FIG.

Since the combined resistance value of the current limiting resistance section 16 connected to the light emitting section 11a differs depending on each connection state, the light emitting section
A difference occurs in the amount of current flowing through 11a, which causes a difference in the amount of light emitted from the light emitting unit 11a and the amount of light reflected from the recording paper P. Further, as shown in FIG. 6, a low output level is shown at a position where the position of the ink-out judgment mark printed by the inkjet recording device 4 is sampled.

FIG. 7 is a diagram showing the relationship between the connection state of the switch section 15 and the voltage ratio of the ink jet recording apparatus of the present invention. In FIG. 7, the voltage ratio (α / β) is the voltage separation ability β
Voltage ratio (α / β) between the average value α of the voltage values (digital values) A / D converted by the A / D converter of the above and the voltage separability β
It is. In addition, the connection state is based on FIG.
Shows the connection state of SW1 and SW2.

FIG. 8 is a diagram showing a threshold value table. In FIG. 8, the average value γ is the average of the voltage values when the reflected light from the non-printed portion of the recording paper is quantized. The threshold value is a reference value for determining the non-printed portion and the printed portion of the recording paper. Next, the operation of setting the output level and the threshold value of the photoelectric sensor 11 will be described with reference to the flowcharts of FIGS. The flowchart is a control flow stored in the ROM and executed by the CPU unit 1.

First, referring to FIG. 9, based on the detection information from the ink cartridge detection unit 9, the ink tank 31Y,
It is determined whether or not 31M, 31C and 31B have been replaced (step S1). When it is determined that the ink tanks 31Y, 31M, 31C and 31B have been replaced, the sensitivity resetting operation of the photoelectric sensor 11 shown in FIG. 10 is executed (step S3). Figure 1
At 0, first, the connection state of the switch unit 15 and the threshold value setting mode are entered (step S11). When step S11 is entered, the CPU section 1 sets the connection state of the switch section 15 to the a state.

Next, the ink density detecting section 5 converts the reflected light from the non-printed portion of the recording paper into a voltage value represented by a digital value, and the CPU section 1 samples the voltage a prescribed number of times (step S12). Next, the CPU unit 1 calculates the average value α (average value of digital values after A / D conversion) of the sampled voltage values, and calculates the voltage ratio (α / β) with the resolution β of the A / D converter unit 13. A comparison is made with the predetermined range shown in FIG. 7 (step S13). The CPU unit 1 sets the connection state of the switch unit 15 based on the determination result (step S14-).
16).

That is, when the calculated voltage ratio (α / β) is within the predetermined range 1/2 <α / β ≤ 1, the switch unit
The connection state of 15 is maintained in the a state. Voltage ratio (α /
β) is in the predetermined range 1/4 <α / β ≤ 1/2,
The connection state is changed to the b state. When the voltage ratio (α / β) is within the predetermined range α / β ≤ 1/4, the connection state is changed to the c state.

After the CPU section 1 sets the connection state of the switch section 15, the ink density detecting section 5 converts the reflected light from the non-printed portion of the recording paper into a voltage again, and the CPU section 1 samples the voltage a prescribed number of times. Yes (step S17). Then
The CPU unit 1 uses the average value γ (A / A of the sampled voltage values
The average value of the digital values after D conversion is calculated (step S
18), as shown in FIG. 8, the average value γ is calculated from the threshold values stored in the memory unit 2 as a threshold value table.
A threshold value suitable for is selected (step S19). Then, the connection state of the switch unit 15 and the selected threshold value are stored in the memory unit 2 (step S20).

The connection state and the threshold value stored in the memory unit 2 in step S20 are not changed unless the above step is executed again. Further, by changing the connection state according to the voltage ratio (α / β) between the average value α of the voltage values sampled in this way and the voltage separation ability β of the A / D converter unit 13, the photoelectric sensor 11 Since the light emission amount of the light emitting unit 11a can be adjusted appropriately, the light receiving unit 11b
Output level can be maintained at approximately 1/2 <α / β ≦ 1, and the performance of the A / D converter unit 13 can be sufficiently brought out.

On the other hand, in step S1 of FIG. 9, when it is determined that the ink tanks 31Y, 31M, 31C and 31B have not been replaced based on the detection information from the ink cartridge detection unit 9, a display by an operator operation is displayed. It is determined whether or not the cleaning unit 26 has been operated according to the instruction from the operation unit 3, and the cleaning is instructed, and the ejection port 30a is instructed.
Is cleaned, and when the cleaning is completed, the process proceeds to step S3, and the above-described sensitivity resetting operation of the photoelectric sensor 11 is executed.

As described above, in this embodiment, the ink tank 31
Each time the presence or absence of Y, 31M, 31C, 31B is detected, that is, each time it is detected that the ink tanks 31Y, 31M, 31C, 31B have been replaced, the output level of the reflected light received by the light receiving portion 11b is set to the CPU. Since the unit 1 performs sampling a predetermined number of times and sets / changes the amount of current supplied to the light emitting unit 11a based on the average value of the sampled output levels, it periodically emits light every time ink runs out. The amount of current supplied to the light emitting unit 11a can be set to an optimum value by following the deterioration state of the unit 11a. As a result, the recording paper P can be always read with an appropriate sensitivity,
It is possible to improve the accuracy of the ink exhaustion determination.

Further, since the amount of current supplied to the light emitting portion 11a is set / changed every time the print head 30 is cleaned, the light emitting portion 11a is tracked according to the deterioration state of the light emitting portion 11a.
The amount of current supplied to the device can be optimized, and the amount of current can be set / changed in a short cycle. Therefore, for example, even when it is applied to an inkjet recording apparatus that prints only image information having a low black ratio and consumes a small amount of ink, or a facsimile apparatus that is mainly used only for transmission and has few printing opportunities, etc. The recording paper P can be read with an appropriate sensitivity, and the accuracy of ink shortage determination can be improved.

[0046]

According to the first aspect of the present invention, the amount of current supplied to the light emitting portion can be set to an optimum value on a regular basis whenever the ink runs out, following the deterioration state of the light emitting portion. it can. As a result, the recording paper can always be read with an appropriate sensitivity, and the accuracy of the ink exhaustion determination can be improved.

According to the second aspect of the present invention, it is possible to optimize the amount of current supplied to the light emitting portion by following the deterioration state of the light emitting portion each time the print head is cleaned.
The amount of current can be set / changed in a short cycle. Therefore, for example, even when it is applied to an inkjet recording apparatus that prints only image information having a low black ratio and consumes a small amount of ink, or a facsimile apparatus that is mainly used only for transmission and has few printing opportunities, etc. The recording paper can be read with an appropriate sensitivity, and the accuracy of the ink exhaustion determination can be improved.

[Brief description of the drawings]

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

FIG. 2 is a mechanism diagram of an inkjet recording apparatus according to an embodiment.

FIG. 3A is a configuration diagram showing a main part of an inkjet recording apparatus according to an embodiment, and FIG. 3B is a circuit diagram for detecting the presence or absence of an ink tank.

FIG. 4 is a diagram showing marks printed on a recording paper by the inkjet recording device and sampling directions of the marks.

FIG. 5 is a diagram showing a connection state of a switch unit of the inkjet recording apparatus.

FIG. 6 is a diagram showing output levels of photoelectric sensors in respective connected states when the same object is sampled.

FIG. 7 is a diagram showing a relationship between a connection state of a switch unit of the inkjet recording apparatus and a voltage ratio.

FIG. 8 is a diagram showing a threshold value table.

FIG. 9 is a flowchart showing a timing and a method for shifting to an operation of resetting the sensitivity of the photoelectric sensor according to the embodiment.

FIG. 10 is a flowchart showing an operation of resetting the sensitivity of the photoelectric sensor according to the embodiment.

[Explanation of symbols]

 1 CPU part (sampling part, control part) 3 Display operation part (operation part) 4 Ink jet recording device 5 Ink density detection part 8 Ink cartridge 9 Ink cartridge detection part 11 Photoelectric sensor 11a Light emitting part 11b Light receiving part 12 Current voltage conversion resistance part (Sampling unit) 13 A / D converter unit (Sampling unit) 15 Switch unit (Control unit) 16 Current limiting resistor unit (Control unit) 26 Cleaning device (Cleaning unit) 30 Print head 31Y, 31M, 31C, 31B Ink tank 41 Out of ink judgment mark P Recording paper

Claims (2)

[Claims] 1. An ink jet recording apparatus for irradiating an ink end mark printed on a recording paper with light and detecting the presence or absence of ink in an ink cartridge based on the output level of the reflected light. A light emitting unit that emits corresponding light, a light receiving unit that receives the reflected light from the recording paper, an ink cartridge detecting unit that detects whether or not an ink cartridge is installed, and an output of the reflected light received by the light receiving unit. A sampling unit for sampling the level a predetermined number of times, and a current supplied to the light emitting unit based on an average value of the output levels sampled by the sampling unit when the ink cartridge detection unit detects that the ink cartridge is mounted. An inkjet recording apparatus comprising: a control unit that sets / changes an amount. 2. A cleaning unit for cleaning an ejection port of a print head provided in the ink cartridge, and an operation unit for instructing the cleaning unit to clean the ejection port, the control unit comprising: The amount of current supplied to the light emitting unit is set / changed based on an average value of the output levels sampled by the sampling unit when an instruction to perform cleaning is given by the operation unit. Item 2. The inkjet recording device according to item 1.