JP2004142341A - Inkjet recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording device which can urge a cleaning operation for a carriage sliding shaft at a more appropriate time point. <P>SOLUTION: At the time of positioning a carriage which carries a recording head 103 to a target position, a convergence time to the target position is measured, and the measured time is compared with a preliminarily set position convergence limit time. A warning of urging cleaning of the carriage sliding shaft is generated in accordance with the comparison result. Alternatively, a friction load of the carriage is detected in real time from a carriage driving system, and the detected result is compared with a preliminarily set threshold value. The warning of urging cleaning of the carriage sliding shaft is generated in accordance with the comparison result. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ink jet recording apparatus employing an ink jet recording method, and more particularly to movement of a carriage on which an ink jet recording head is mounted.
[0002]
[Prior art]
Conventionally, in an ink jet recording apparatus, particularly an ink jet recording apparatus for a large format, an ink mist to a carriage sliding shaft due to aging between a bearing portion of a carriage that moves and carries a recording head and a sliding shaft, The frictional load between the two, that is, the sliding load increases (the difference between the static friction and the dynamic friction increases) due to the effects of adhesion of dust and lubricant and unevenness of the solid surface, and as a result, the carriage moves to the target position. The convergence of the carriage may deteriorate, and the carriage may operate abnormally. For example, for a recovery operation such as suction of a nozzle of the recording head, it is necessary to accurately stop the positioning of the recording head with respect to the recovery device. In such a case, if the end of the carriage movement to the target position is delayed due to the deterioration of the convergence, necessary processing cannot be performed quickly.
[0003]
Conventionally, to solve such problems, (1) reduce the mist by changing the particle diameter of the ink, (2) a mechanism for releasing the mist to the outside of the housing by a fan or the like, (3) the bearing portion of the carriage and To reduce the frictional load with the carriage sliding shaft, the contact portion between both solid surfaces is reduced (mechanically). (4) Oil such as lubricant is applied to the carriage sliding shaft to smooth the sliding and reduce the frictional load. (5) reduce the weight of the carriage, (6) reduce the stop accuracy (extend the stop range) of the carriage, and / or the like. We try to improve convergence.
[0004]
[Problems to be solved by the invention]
However, in practice, the above-mentioned deterioration of the convergence is unavoidable due to the time-dependent factor of the apparatus, and eventually, it is necessary for the user to clean (clean) the carriage sliding shaft with a cloth or the like. . Conventionally, the timing for prompting the cleaning operation includes a point in time when the number of recordings reaches a predetermined number (the count is performed every time one sheet is recorded) and a point in time when the amount of recording data reaches the predetermined amount (hard count of the recording data amount) However, since the amount of ink mist ejected from the recording head in each recording apparatus is not quantitative, the actual friction load of the carriage is not quantitative, and If the number of sheets or the predetermined data amount is too small, there is a possibility that the carriage may abnormally operate or stop abnormally before such a point is reached. If and when cleaning is performed on a regular basis, cleaning should be performed at a time when cleaning is not always necessary (ie, earlier than necessary). It has been a result of requesting the work.
[0005]
The present invention has been made in such a background, and an object of the present invention is to provide an ink jet recording apparatus capable of prompting a cleaning operation of a carriage sliding shaft at a more appropriate time.
[0006]
[Means for Solving the Problems]
A first inkjet recording apparatus according to the present invention includes a carriage mounted with an inkjet recording head and moving on a carriage sliding shaft, a carriage drive motor for moving the carriage, and a carriage drive for driving the carriage drive motor. System, a medium transport mechanism for transporting the recording medium, a transport drive motor for driving the medium transport mechanism, a transport drive system for driving the transport drive motor, and when positioning the carriage to a target position, Measuring means for measuring the convergence time to the target position, comparing means for comparing this measured time with a preset position convergence limit time, and a warning urging the cleaning of the carriage sliding shaft according to the comparison result. And a warning generating means for issuing a warning.
[0007]
The convergence time to the target position is considered to depend on the magnitude of the frictional load between the carriage bearing and the carriage sliding shaft, and this convergence time is compared with a preset threshold, a position convergence limit time. By doing so, it is possible to appropriately determine the timing of the generation of the warning prompting the cleaning. Specific examples of the warning may include displaying a message, turning on a lamp, and generating a sound or voice.
[0008]
A second ink jet recording apparatus according to the present invention includes a carriage mounted with an ink jet recording head and moving on a carriage sliding shaft, a carriage drive motor for moving the carriage, and a carriage drive for driving the carriage drive motor. System, a medium transport mechanism for transporting the recording medium, a transport drive motor for driving the medium transport mechanism, a transport drive system for driving the transport drive motor, and a real-time transfer of the friction load of the carriage from the carriage drive system. A load detecting means for detecting the detection result, a comparing means for comparing the detection result with a predetermined threshold value, and a warning generating means for issuing a warning for urging the cleaning of the carriage sliding shaft according to the comparison result. It is characterized by having.
[0009]
In the second ink jet recording apparatus, more specifically, the load detecting means has a current detecting means for detecting in real time a current proportional to a friction load of the carriage from the carriage driving system, and the comparing means includes , And compares the detected current with a predetermined overcurrent warning threshold.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
[0011]
FIG. 1 is a diagram showing an external configuration around a carriage of an ink jet recording apparatus to which the present invention is applied. In the drawing, reference numeral 103 denotes a recording head mounted on a carriage (not shown); 104, a linear scale; 14, a carriage (CR) motor as a main scanning motor; and 501, a sub-scanning motor. As described above, the carriage on which the recording head 103 is mounted is driven by the CR motor 14 via the belt 502 in the left and right directions in the figure. The recording paper 503 is conveyed by a paper conveyance roller 504 driven by a sub-scanning motor 501 along a “paper feeding direction” in the drawing. At the time of printing, a print head 103 forms a one-page image by repeating print scan while feeding paper for a designated pass for each band print. In the figure, reference numeral 505 denotes an image formed on the recording paper 503.
[0012]
FIG. 2 is a block diagram illustrating a configuration example of a control unit of the inkjet recording apparatus according to the first embodiment of the present invention. In FIG. 1, a CPU 11 is a processor that controls the entire circuit. The CPU 11 has a built-in ROM 8 that stores a control program and a RAM 9 that provides a memory area for work and temporary storage. The system controller 20 is connected to an external device, receives data to be recorded from the external device, receives various instructions, and transmits it to the CPU 11. The system controller 20 is also connected to the operation panel 40 and controls display on the display unit 41 and input from the input unit 42.
[0013]
The application specific integrated circuit (ASIC) 12 controls the CR motor driver 13 under the control of the CPU 11, the overcurrent information from the filter 16, the carriage position information from the CR linear encoder 17, and the motor rotation position information from the hall sensor 18. Is a dedicated control circuit for obtaining
[0014]
The CR motor driver 13 is a driver for driving the CR motor 14. The CR motor 14 in the present embodiment is a DC motor that moves a carriage. Here, a DC brushless motor is used. INDUSTRIAL APPLICABILITY The present invention is suitably applied to an apparatus in which feedback control is used for movement control, such as a DC motor.
[0015]
The current detector 15 is a circuit for detecting an overcurrent supplied to the CR motor 14. From the SENSE output terminal of the CR motor driver 13, a current that is substantially proportional to the frictional load of the carriage is output and converted to a voltage level by the resistor 21. This voltage level is compared with the reference voltage Vref by the comparator 22. The reference voltage Vref defines a reference level such that the driver 13 is destroyed when the voltage level exceeds this level. The comparator 22 generates an overcurrent detection signal when such an overcurrent flows through the driver 13. The filter 16 samples and filters the overcurrent detection signal, and inputs the filtered signal to the ASIC 12.
[0016]
The CR linear encoder 17 is an encoder that extracts a signal from the linear scale 104 (FIG. 1) used for feedback control of the CR motor 14. The linear scale is a commonly used member in the ink jet printing apparatus, and extends along the movement path of the carriage, and is used for detecting the current position of the carriage and synchronizing the ink ejection timing. The Hall sensor 18 is a sensor that outputs a rotation position signal of the CR motor 14, and outputs, for example, a 3-bit digital signal indicating the rotation angle of the motor. This digital signal is input to the ASIC 12, and a PWM (Pulse
(Width Modulation) control section 32.
[0017]
The ASIC 12 includes a PWM control unit 32 and a direction detection / counter 34. The PWM control unit 32 receives a command from the CPU 11 via the interface (I / F) 31. The direction detection / counter 34 receives the phase signals of the A and B phases shifted by 90 ° from the CR linear encoder 17, detects the rotation direction of the CR motor 14, and counts the output pulses of the encoder. To detect the relative movement amount of the carriage. This detection result is input to the CPU 11.
[0018]
To rotate the CR motor 14 to move the carriage, the CPU 11 outputs a rotation command to the ASIC 12. In response, the ASIC 12 outputs a PWM signal by the PWM control unit 32 in itself. By controlling the CR motor driver 13 in response to the PWM signal, a current flows through the CR motor 14 and the CR motor 14 rotates.
[0019]
By the rotation of the CR motor 14, a signal from the Hall sensor 18 is output, and the carriage moves. As a result, the signal from the linear scale is taken out, the A-phase and B-phase signals from the CR linear encoder 17 enter the ASIC 12, and the counter of the ASIC 12 performs a counting operation. Based on this count value, the rotation control of the CR motor 14 is performed by the feedback control of the CR motor 14.
[0020]
Although the configuration of the control device shown in FIG. 2 and its basic operation itself are publicly known, the feature of the present invention is that when the frictional force between the bearing portion and the sliding shaft increases due to aging or the like, the fact can be properly adjusted. This is in program (software) control by the CPU 11 for detection.
[0021]
Next, the operation of the recording apparatus according to the present embodiment will be described with reference to the flowchart of FIG.
[0022]
First, when the power of the recording apparatus is turned on, the position of the CR motor 14 is feedback-controlled by a signal from the CR linear encoder 17, and the CR motor 14 is in a servo lock standby state. Thereafter, when a movement command arrives, feedback processing is performed to output a PWM signal from the PWM control unit 32 of the ASIC 12 to the CR motor driver 13 in order to rotate the CR motor 14 to move the carriage. Trajectory movement control of constant speed and deceleration is performed (S11).
[0023]
Next, a process for causing the carriage to reach the final target position is performed. In this process, first, a difference between the target position and the current position is obtained, and it is determined whether the value is within ± 3 pulses (S12). If it is within ± 3 pulses, the normal movement ends. The current position is detected based on the operation output of the CR linear encoder 17 related to the linear scale 104.
[0024]
If not within ± 3 pulses, time measurement is started, and it is determined whether or not this time InPosTime has reached a preset position convergence limit time T seconds (S13). If the position convergence limit time has not reached T seconds, a position feedback control process for converging to the target position is further performed (S14), and the process returns to step S12.
[0025]
If the position convergence limit time T seconds (for example, about 10 seconds) has been reached, the position convergence timeout flag (InPosTimeOut_Flg) is set (S15), and the drive of the CR motor is stopped (S16). Thereafter, no movement command is accepted until this flag is cleared. The position convergence timeout flag is cleared in response to a user response operation in response to a warning urging the user to perform cleaning, or when the power is turned on next time.
[0026]
As shown in the flowchart in FIG. 4, the main processing unit checks whether or not the position convergence timeout flag InPosTimeOut_Flg is set (S21), and if it is set (S22, Yes), the display on the operation panel 40 A warning message is displayed on the unit 41. Alternatively, the cleaning operation can be prompted by a sound or voice by a sound generator such as a buzzer (not shown). After step S22, other processing during the main processing is performed (S23).
[0027]
By doing so, it is possible to prompt the cleaning operation at a more appropriate point in time, and it is possible to avoid an abnormal operation of the carriage and troubles caused by the operation, and to perform a more stable recording operation.
[0028]
FIG. 5 is a block diagram illustrating a configuration example of a control unit of the inkjet recording apparatus according to the second embodiment of the present invention. The appearance configuration around the carriage is as shown in FIG. 1, as in the first embodiment. In the configuration of FIG. 5, an analog-to-digital converter (ADC) 12 is provided in the CPU 11, and the SENSE output of the CR motor driver 13 is input to an analog signal input terminal of the ADC 12. Other configurations are the same as those in FIG. In this embodiment, an increase in the frictional force of the carriage sliding shaft is detected by detecting a considerably increased load, which does not reach the occurrence of the overcurrent detection signal from the SENSE output of the CR motor driver 13. Is what you do.
[0029]
Next, a check operation in the ink jet recording apparatus of the present embodiment will be described with reference to a flowchart of FIG. This process is an interrupt process and is executed periodically.
[0030]
In the above-described trajectory movement of acceleration, constant velocity, and deceleration by the feedback processing, the current value (voltage conversion value) is always (periodically) detected from the ADC 12 in order to detect the friction load current of the carriage. It is read by the CPU 11 (S31) and set to the variable ADC_Val. Next, the preset overcurrent warning threshold value (variable NearOC._Val) is compared with the value of the variable ADC_Val (S32), and if the ADC_Val value does not exceed the overcurrent warning threshold value, The processing ends, and the feedback processing continues.
[0031]
When the ADC_Val value exceeds the overcurrent warning threshold value, the value is close to the overcurrent detection value. Therefore, the flag variable NearO. C. "1" is set to _Flg (S33). Next, the present process ends. In this case, the feedback processing is continuously performed because the warning level is set.
[0032]
The output of the warning message in this embodiment can be performed by the processing shown in FIG. 4, as in the first embodiment. In this case, the flag to be checked is NearO.Time instead of InPosTimeOut_Flg. C. _Flg.
[0033]
Note that the first and second embodiments can be used in combination.
[0034]
Although the preferred embodiment of the present invention has been described above, various modifications and changes other than those described above can be made.
[0035]
【The invention's effect】
According to the present invention, the actual friction load of the carriage sliding shaft can be determined based on the convergence time of the carriage to the target position or based on the detection result of the friction load of the carriage. It is possible to issue a warning prompting the cleaning of the carriage sliding shaft at a more appropriate timing. As a result, an abnormal operation or abnormal stop of the carriage can be avoided, and a more stable recording operation can be performed.
[Brief description of the drawings]
FIG. 1 is a diagram showing an external configuration around a carriage of an ink jet recording apparatus to which the present invention is applied.
FIG. 2 is a block diagram illustrating a configuration example of a control unit of the inkjet recording apparatus according to the first embodiment of the present invention.
FIG. 3 is a flowchart illustrating an operation of the recording apparatus according to the first embodiment of the present invention.
FIG. 4 is a flowchart illustrating an operation of a main processing unit according to the embodiment of the present invention.
FIG. 5 is a block diagram illustrating a configuration example of a control unit of an inkjet recording apparatus according to a second embodiment of the present invention.
FIG. 6 is a flowchart illustrating an operation of the recording apparatus according to the second embodiment of the present invention.
[Explanation of symbols]
11 CPU
12 Control ASIC
13 CR motor driver 14 CR motor 15 Current detector 16 Filter 17 CR linear encoder 18 Hall sensor 20 System controller 40 Operation panel 41 Display section 42 Input section

Claims (4)

A carriage mounted with an inkjet recording head and moving on a carriage sliding shaft;
A carriage drive motor for moving the carriage,
A carriage drive system for driving the carriage drive motor;
A medium transport mechanism that transports the recording medium;
A transport drive motor for driving the medium transport mechanism,
A transport drive system for driving the transport drive motor;
When positioning the carriage at a target position, a measuring means for measuring a convergence time to the target position,
Comparing means for comparing the measured time with a preset position convergence limit time,
An ink jet recording apparatus comprising: a warning generating unit that generates a warning urging the cleaning of the carriage sliding shaft according to the comparison result. A carriage mounted with an inkjet recording head and moving on a carriage sliding shaft;
A carriage drive motor for moving the carriage,
A carriage drive system for driving the carriage drive motor;
A medium transport mechanism that transports the recording medium;
A transport drive motor for driving the medium transport mechanism,
A transport drive system for driving the transport drive motor;
Load detection means for detecting in real time the friction load of the carriage from the carriage drive system,
Comparing means for comparing the detection result with a predetermined threshold value;
An ink jet recording apparatus comprising: a warning generating unit that generates a warning urging the cleaning of the carriage sliding shaft according to the comparison result. The load detecting means includes a current detecting means for detecting a current proportional to a frictional load of the carriage from the carriage driving system in real time, and the comparing means includes a detecting means for detecting the detected current and a predetermined overcurrent warning threshold value. 3. The ink jet recording apparatus according to claim 2, wherein The inkjet recording apparatus according to claim 1, wherein the carriage drive system performs feedback control of the carriage drive motor based on a target position and a current position of the carriage.

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