JP2000037918A - Scanning device and scanning member operation monitoring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect an abnormality in the operation of a carriage 1 or an occurrence of an abnormality in a printing apparatus which caused the operation of the carriage 1 quickly, reliably, and accurately in an apparatus for printing by scanning a carriage 1. . In addition, the print throughput is not reduced due to the abnormality detection. A printing apparatus according to the present invention includes a CPU (1).
2 and a control system including a photo interrupter 11 and the like. The position where the carriage 1 should be (logical position) is calculated, the position where the carriage 1 actually exists (actual position) is detected based on an input from the photo interrupter 11, and both positions are compared to determine the position of the carriage 1. Determine the operating state. This makes it possible to detect an operation abnormality that the actual position of the carriage 1 is not at the logical position. Further, since the operation of returning the carriage 1 to the detection position of the photo interrupter 11 for detecting an abnormality is not performed, the print throughput does not decrease.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to scanning (main scanning) relative to a medium (for example, a print medium or a document).
The present invention relates to a method for monitoring the operation of a scanning member (for example, a member such as a print head or a reading head or a carriage on which the scanning head is mounted) and a scanning device (for example, a printing device or an image reading device) including the method. More specifically, for example, in an apparatus for performing printing by scanning a carriage on which a print head is mounted, the present invention relates to a method for detecting the presence or absence of an abnormality during carriage scanning and a printing apparatus including means for realizing the method.

[0002]

2. Description of the Related Art For example, in a printing apparatus, an abnormality may occur in the main scanning in the course of performing a printing operation by causing a carriage on which a print head is mounted to perform a main scanning relative to a print medium. For example, there are cases where the print medium has not been set properly and movement of the carriage is hindered by the print medium, or when a problem has occurred in the printing apparatus main body.

In order to detect this abnormal operation, in a conventional printing apparatus, during a series of printing processes, for example,
At predetermined time intervals, control is performed to return the carriage to the detection position of a sensor such as a photo interrupter, and if the return of the carriage is detected, it is determined that there is no abnormality in the operation of the carriage.

[0004]

However, in such a conventional operation monitoring method, it is determined whether or not the carriage is at a position where it should be in a normal operation (hereinafter referred to as a "logical position"). Or an abnormality determination of the apparatus according to this determination cannot be performed. That is, since the occurrence of an abnormality is detected based on whether or not the carriage has returned to the detection position of the sensor, the abnormal operation or the cause thereof is only performed when a situation occurs in which the carriage cannot return to the detection position of the sensor. Although it can be detected that the abnormal operation has occurred, it cannot detect the abnormal operation in which the carriage is not at the logical position or the occurrence of the abnormal operation that caused the abnormal operation.

In addition, since the operation of returning the carriage to the detection position of the sensor is performed during the printing process, the printing throughput is also reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide an apparatus for detecting an abnormality in a carriage operation or an abnormality in a scanning device which has caused the abnormality. It is to enable quick, reliable and accurate detection.

It is another object of the present invention to detect an abnormal operation without returning the carriage to the detection position of the sensor and to prevent a decrease in print throughput.

[0008]

Therefore, a scanning device according to the present invention scans a scanning member relative to a medium and calculates a logical position of the scanning member;
Real position detecting means for detecting the real position of the scanning member; and determining means for comparing the calculated logical position with the detected real position to determine an operation state of the scanning member.

Here, the scanning device may further include a notifying unit for notifying the abnormality when the determining unit determines the abnormality of the operation of the scanning member. Further, the determination means may perform the determination at predetermined time intervals. Further, the determination means may change and set the predetermined time interval in accordance with a driving speed of the scanning member.

The determining means compares the calculated logical position with the real position only when all of the real positions detected continuously plural times by the real position detecting means are the same. It can be determined whether or not the operation of the scanning member is normal. Further, the determination means may narrow a time interval for performing the determination when the actual positions detected in the plurality of consecutive times are not all the same.

The logical position calculating means calculates a logical position as to whether or not the scanning member is at a predetermined position,
The actual position detecting means may detect the actual position as whether or not the scanning member is at the predetermined position. Further, the determination means may make the determination when the logical position is the predetermined position. Further, the determination means may perform the determination when the actual position is the predetermined position.

Here, the scanning device may be a printing device, the scanning member may be a print head or a carriage on which the print head is mounted, and the medium may be a print medium. Further, the recording head may be an ink jet head.

Further, the actual position detecting means may include one or more sensors along the scanning direction. Further, the predetermined position may be a detection position of the sensor.

An operation monitoring method according to the present invention monitors an operation of a scanning member scanned relative to a medium, calculates a logical position of the scanning member, and detects an actual position of the scanning member. And determining the operating state of the scanning member by comparing the calculated logical position with the detected actual position.

According to the above arrangement, it is possible to quickly, reliably and accurately detect an abnormality in the operation of the scanning member (carriage or the like) or an abnormality in the scanning device which has caused the abnormality. Further, an abnormal operation can be detected without requiring an operation of returning the scanning member to the sensor detection position, and a decrease in throughput of the scanning device (such as a printing device) can be prevented.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the following, an apparatus for printing on a print medium using a print head will be described as an example.

[First Embodiment] FIG. 1 shows a configuration example of a printing apparatus according to a first embodiment of the present invention. In FIG.
A carriage 1 on which an inkjet head can be removably mounted, for example, is shown. The carriage 1 includes a bearing 3, and a guide shaft 2 is inserted through the bearing 3 and is movable along the guide shaft 2 in the main scanning direction (the direction of the arrow S in the drawing). The carriage 1 is fixed to a timing belt 4, and the timing belt 4 is stretched between pulleys 5A and 5B arranged on both sides of the printing apparatus. Power for moving in the S direction is transmitted from the timing belt to the carriage 1. A driving force is transmitted to the one pulley 5B from the carriage motor 6 via an appropriate transmission mechanism.

In this embodiment, one sensor 11 is provided at a position corresponding to the home position of the carriage 1. In the illustrated example, the sensor 11 has the form of a transmission type photo interrupter, and can detect that the carriage 1 is at the home position by blocking the optical axis between the light emitting unit and the light receiving unit with the light shielding member provided on the carriage 1. . As this sensor, a reflection type photo sensor can be used, or an appropriate sensor such as a magnetic sensor can be used in addition to a sensor using such light.

Paper set on paper pan 9, OHP
A suitable print medium (not shown) such as a film or cloth is fed from here to the print position. Then, the surface to be printed is regulated by the platen roller 7, and is conveyed by the platen roller 7 in response to driving of the conveyance motor 8 during printing or the like. In the middle of the print medium feeding path, a feed roller 10 is provided so as to face the platen roller 7. The feed roller 10 presses the print medium toward the platen roller 7, and can pinch and transport the print medium in cooperation with the platen roller 7.

The recovery device 21 performs an operation for recovering the ink discharge performance of the print head by the ink-jet system or maintaining the ink discharge performance in a good state during a standby for a print command, before or after a print operation or at an appropriate timing during the print operation. (Capping, suction, wiping, etc.).

FIG. 2 shows a configuration example of a control system of the apparatus shown in FIG. The control system includes a CPU 12, an interface 13, input ports 14, 26, a data memory 15, a program memory 16, a working memory 17, and a motor control circuit 1.
8, a motor driver 19, a head control circuit 20, and an output port 24. The CPU 12 can be in the form of a microprocessor, and the program memory 16 can be in the form of a ROM storing programs and other related data corresponding to the processing procedure described later with reference to FIG. 3, and has an area usable as a work area. Working memory 1
7 allows the form of RAM.

The CPU 12 includes a command signal and a print information signal read from the host device 23 connected via the interface 13 to the data memory 15 and a program stored in the program memory 16 and the working memory 17. And the print operation is controlled based on the print command. That is, the CPU 12 controls the carriage motor 6 and the transport motor 8 via the motor control circuit 18 and the motor driver 19, and controls the print head via the head control circuit 20 based on the print information stored in the data memory 15. To print. Note that the host device 23 is a supply source that supplies image data relating to printing to the printing device of the present embodiment, and may be an information processing device such as a computer or a word processor, or may have a form such as an image reader.

The display 22 displays the status of the apparatus, abnormalities, and other messages.
Is supplied via The operation unit 25 has a power switch for turning on / off the power supply circuit 27, a key for setting an online / offline state with the host device 23, a key for setting a print mode, and the like. It is supplied via input port 26.

FIG. 3 is a flowchart showing an example of a monitoring procedure executed by the control system of FIG. 2 in the first embodiment. When this procedure is started (step S300),
First, based on the driving speed of the carriage 1 and the elapsed time from the start of driving, the position where the carriage 1 should be at that time, that is, the logical position is calculated (step S301). And the logical position is the photointerrupter 1
1 is determined (step S302), and the logical position is stored as either the detected position or the non-detected position of the photo interrupter 11 (step S30).
3, S304).

Next, based on the input from the photo interrupter 11, the actual position of the carriage 1 (the position where the carriage 1 actually exists) is detected. Specifically, an input (signal) from the photo interrupter 11 is transmitted to the CPU 12 via the input port 14, so that the state of this input may be checked (step S305). Next, the carriage 1
Is determined at the detection position of the photo interrupter 11 (step S306), and the actual position of the carriage 1 is determined as either the detection position or the non-detection position of the photo interrupter (steps S307 and S308).

Then, the logical position and the actual position are compared (step S309). If the two positions do not match, it is determined that the operation is abnormal (step S310). It is determined that it is normal. For example, when the logical position is the non-detection position of the photo-interrupter 11, the photo-interrupter 11 does not detect the carriage 1, and the real position is the non-detection position of the photo-interrupter 11, the operation is normal. Is determined.

As described above, the logical position and the actual position are determined as either the detected position or the non-detected position of the photo interrupter 11 used as a home position sensor. Therefore, when the carriage 1 is not at the detection position of the photo-interrupter 11, that is, when it is not at the home position, the carriage 1 is similarly treated as being at the non-detection position. Therefore, in order to detect the abnormality more reliably, it is desirable to make the determination as much as possible when the logical position or the actual position of the carriage 1 is the detection position of the photo interrupter 11.

In addition to the photointerrupter 11, one or more detecting means (such as a photointerrupter) can be provided along the scanning direction, and the operation can be monitored using the detection results. In a case where n photointerrupters are further provided to make a total of n + 1 photointerrupters, the logical position and the actual position of the carriage 1 are respectively n
It will be determined in +2 ways. That is, since the logical position or the real position does not correspond to two or more detection positions of the photointerrupter at the same time, the logical position and the real position respectively correspond to one or both of the detection positions of the n + 1 photointerrupter. It is determined that there are n + 2 possible positions (non-detection positions). n +
Since the operation abnormality is detected by comparing the logical position and the actual position determined in two ways, it is possible to detect the abnormality more reliably.

In the above monitoring procedure, for example, when the carriage 1 is logically determined to have returned to the home position at the time of carriage return, or when the detection is actually performed, and at a predetermined time interval from that time. It can be activated every time. Further, the predetermined time interval may be changed and set in accordance with the driving speed of the carriage 1. As an example of starting up according to the drive speed of the carriage 1, it is conceivable to start up every time the carriage 1 moves by a fixed amount at any drive speed. With this configuration, the abnormality determination can be performed at the same time and condition regardless of the driving speed.

When an abnormality in the operation is detected by the above monitoring procedure, an appropriate notification can be given to the operator to urge the user to take necessary measures. As a means of the notification, an appropriate display may be provided on the display 22 provided in the printing apparatus main body, or a warning sound may be output by a buzzer or the like. Alternatively, the notification may be made to the host device 23 through the interface 13 and the application may be performed using an application and display means on the host device side. In any case, in response to such notification, the operator can perform processing such as, for example, canceling an abnormal setting state of the print medium.

[Second Embodiment] In the second embodiment of the present invention, the actual position of the carriage 1 is intended to be detected more accurately than in the first embodiment.

In the above-described first embodiment, for example, when the actual position of the carriage 1 which has been returned to the home position is detected by the photointerrupter 11 which is attached near the home position and whose home position is the detection position, Accurate detection is possible. However, for example, when the actual position of the carriage 1 that simply passes through the detection position of the photo interrupter 11 is detected (for example, when the carriage 1 moves toward the recovery device 21 to the left of the home position in FIG. 1). Since the input value from the photo interrupter 11 often does not become constant, accurate detection of the actual position may be difficult. Therefore, in the second embodiment, the photo interrupter 1
Check the input from 1 multiple times continuously, and if all the detection results are not the same, determine that the carriage 1 is passing the detection position of the photo interrupter 11 and do not compare with the logical position. Thus, more accurate detection of the actual position is attempted. Hereinafter, portions of the second embodiment that are different from the first embodiment will be described.

FIG. 4 is a flowchart showing an example of a monitoring procedure in the second embodiment. Also in the second embodiment, first, steps S400 to S404 similar to steps S300 to S304 of the first embodiment are performed. Next, the actual position of the carriage 1 is continuously checked a plurality of times (n times) (steps S405 to S409). As in steps S305 to S308 of the first embodiment, the photointerrupter 11
Is checked (step S405), and the carriage 1
Is determined to be at or not at the detection position of the photointerrupter 11 (S406 to S406).
S408).

It is determined whether or not all the detection results of the actual position are the same (step S410). If they are not the same, it is determined that the carriage 1 is passing the detection position of the photo interrupter 11 and the like. Do not compare with position. Thus, it is possible to avoid detection when the input value from the photo interrupter 11 may be unstable.
However, in this case, since monitoring is not performed until the next monitoring procedure is started, the interval from the previous monitoring may be long. Therefore, the monitoring interval is set shorter than the normal case (predetermined time) so that the monitoring interval does not become longer (step S414).

If all the detection results of the actual position are the same, a comparison is made with the logical position (step S41).
1). If the two positions do not match, it is determined that the operation of the carriage is abnormal (step S412), and if the two positions match, it is determined that the operation is normal. If it is determined that the operation is normal and the monitoring interval is shorter than the predetermined time, the monitoring interval is returned to the predetermined time (step S413).

[Others] In the above description,
The case where the present invention is applied to an apparatus that performs printing by main scanning of a print head on a print medium has been described. However, the present invention can be effectively applied to an apparatus having a member that scans a medium. That is, such an apparatus may be an apparatus that reads an image by scanning a reading head with respect to a document, or may be an apparatus that has both reading and recording functions.

In the above example, a printer using an ink jet system has been described as an example of a printer, but a printer to which the present invention can be applied may be a dot matrix printer such as a wire dot system or a thermal transfer system, or a type printer. However, when applied to an inkjet type printing apparatus, among them, a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection is provided. The present invention provides an excellent effect in a print head and a printing apparatus of a type in which a change in the state of ink is caused by thermal energy. According to such a method, it is possible to achieve high density and high definition of the print.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method can be applied to both the so-called on-demand type and the continuous type.
By applying at least one drive signal corresponding to the printing information and providing a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer arranged corresponding to the sheet or the liquid path in which This is effective because it generates heat energy in the electrothermal transducer, causing film boiling on the heat-acting surface of the print head, and as a result, it is possible to form bubbles in the liquid (ink) one-to-one corresponding to this drive signal. It is.
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 a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. US Pat. No. 4,463,359 discloses a pulse-shaped drive signal.
No. 4,345,262 are suitable. If the conditions described in U.S. Pat. No. 4,313,124 relating to the rate of temperature rise of the heat acting surface are adopted, more excellent printing can be performed.

As the configuration of the print head, in addition to the combination (straight liquid flow path or right-angle liquid flow path) of the combination of the discharge port, the liquid path, and the electrothermal converter as disclosed in the above-mentioned respective specifications, A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting portion is arranged in a bending region, is also included in the present invention. In addition, for multiple electrothermal transducers,
JP-A-59-123670 which discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer and JP-A-59-123670 which discloses a configuration in which an opening for absorbing a pressure wave of heat energy corresponds to a discharge portion. The effect of the present invention is effective even in a configuration based on JP-A-138461. That is, according to the present invention, printing can be performed reliably and efficiently regardless of the form of the print head.

In addition, in the case of the serial type as described above, a print head fixed to the apparatus main body or an electric connection with the apparatus main body or ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type print head that can be supplied or a cartridge-type print head in which an ink tank is provided integrally with the print head itself is used.

It is preferable to add recovery means for the print head, preliminary auxiliary means, and the like, which are provided as components of the printing apparatus in the present invention, since the effects of the present invention can be further stabilized. . To be more specific, capping means for the print head, cleaning means, pressurizing or suction means, preheating means using an electrothermal converter or another heating element or a combination thereof, and printing Performing a preliminary ejection mode for performing another ejection is also effective for performing stable printing.

The type and number of print heads to be mounted are, for example, one for each single color ink.
In addition to those provided with only a plurality of inks, a plurality of inks may be provided corresponding to a plurality of inks having different print colors and densities. That is, for example, the print mode of the printing apparatus is not limited to the print mode of only the mainstream color such as black, but may be any of a print head integrally formed or a combination of a plurality of print heads. The present invention is also very effective for an apparatus provided with at least one of full colors by color mixing.

In addition, in the embodiment of the present invention described above, the ink is described as a liquid.
An ink that solidifies at room temperature or below, and softens or liquefies at room temperature, or in the inkjet system, adjusts the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to keep the viscosity of the ink in a stable ejection range. Since the temperature is generally controlled as described above, any type of ink may be used as long as the ink is in a liquid state when the use print signal is applied. In addition, the temperature rise due to thermal energy can be positively prevented by using it as energy for changing the state of the ink from a solid state to a liquid state, or ink that solidifies in a standing state to prevent evaporation of the ink can be used. In any case, thermal ink is liquefied by application of heat energy according to a print signal, and a liquid ink is ejected, or a thermal ink such as an ink that starts solidifying when it reaches a print medium. The present invention is also applicable to a case where an ink that liquefies for the first time by energy is used. In such a case, the ink is held in a state of being held as a liquid or solid substance in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. Alternatively, it may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet printing apparatus of the present invention is not limited to the one used as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

In addition, in this specification, “print” means not only a case where significant information such as characters and figures are formed, but also a meaning which can be visually perceived by humans regardless of significance. Regardless of whether it is materialized,
This also refers to a case where an image, a pattern, a pattern, or the like is widely formed on a print medium or the medium is processed.

Here, the term "print medium" refers not only to paper used in a general printing apparatus, but also to any material that can accept ink, such as a cloth, a plastic film, or a metal plate.

In addition, the term “ink” is to be interpreted broadly as in the definition of “print” described above, and is applied to a print medium to form an image, a pattern, a pattern, or the like, or to form a print medium. Refers to a liquid that can be used for the processing of

[0048]

As described above, according to the present invention,
An abnormality in the operation of the scanning member (carriage or the like) or the occurrence of an abnormality in the scanning device that has caused the abnormality can be quickly, reliably, and accurately detected. Further, an abnormal operation can be detected without requiring an operation of returning the scanning member to the sensor detection position, and a decrease in throughput of the scanning device (such as a printing device) can be prevented.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of a printing apparatus according to a first embodiment and a second embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a control system of the printing apparatus according to the first embodiment and the second embodiment of the present invention.

FIG. 3 is a flowchart illustrating an example of a monitoring procedure according to the first embodiment of the present invention.

FIG. 4 is a flowchart illustrating an example of a monitoring procedure according to the second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 carriage 2 guide shaft 3 bearing 4 timing belt 5A, 5B pulley 6 carriage motor 7 platen roller 8 transport motor 9 paper pan 10 feed roller 11 photo interrupter 12 CPU 13 interface 14 input port 15 data memory 16 program memory 17 working memory 18 motor Control circuit 19 Motor driver 20 Head control circuit 21 Recovery device 22 Display device 23 Host device 24 Output port 25 Operation unit 26 Input port 27 Power supply circuit

Claims (14)

[Claims] 1. A scanning device that scans a scanning member relative to a medium, comprising: a logical position calculating unit that calculates a logical position of the scanning member; and a real position detection unit that detects an actual position of the scanning member. And a determining means for comparing the calculated logical position with the detected actual position to determine an operation state of the scanning member. 2. The apparatus according to claim 1, wherein the scanning device further comprises a notifying unit for notifying the abnormality when the determining unit determines an abnormality in the operation of the scanning member. A scanning device according to claim 1. 3. The scanning device according to claim 1, wherein the determination unit performs the determination at predetermined time intervals. 4. The scanning device according to claim 3, wherein the determination unit changes and sets the predetermined time interval according to a driving speed of the scanning member. 5. The determination means compares the calculated logical position with the real position only when all of the real positions detected a plurality of times consecutively by the real position detection means are the same. 5. The scanning device according to claim 1, wherein it is determined whether the operation of the scanning member is normal. 6. The method according to claim 5, wherein the determination unit narrows a time interval for performing the determination when the actual positions detected in the plurality of times are not all the same.
The scanning device according to claim 1. 7. The logical position calculating means calculates a logical position as to whether the scanning member is at a predetermined position, and the actual position detecting means determines whether the scanning member is at the predetermined position. 7. The scanning device according to claim 1, wherein an actual position is detected. 8. The scanning device according to claim 7, wherein the determination unit performs the determination when the logical position is the predetermined position. 9. The scanning device according to claim 7, wherein the determination unit performs the determination when the actual position is the predetermined position. 10. The scanning device is a printing device,
10. The scanning device according to claim 1, wherein the scanning member is a print head or a carriage on which the print head is mounted, and the medium is a print medium. 11. The printing apparatus according to claim 10, wherein said recording head is an ink jet head. 12. The apparatus according to claim 1, wherein the actual position detecting means has one or more sensors along the scanning direction. 13. The apparatus according to claim 12, wherein the predetermined position is a detection position of the sensor. 14. A method for monitoring the operation of a scanning member that is scanned relative to a medium, comprising: calculating a logical position of the scanning member; and detecting an actual position of the scanning member. Determining the operation state of the scanning member by comparing the calculated logical position with the detected actual position.