JP5659638B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus.

2. Related Art Inkjet recording apparatuses capable of forming images on various recording media such as plain paper and plastic thin plates are known. The ink jet recording apparatus includes a head that ejects ink from nozzles. By ejecting ink as fine droplets from the nozzles of the head toward the recording medium, an image can be formed on the recording medium.
In an inkjet recording apparatus capable of forming an image on a recording medium by moving a carriage on which a head is mounted, for performing maintenance or the like on a non-recording area that is on the carriage movement path and is out of the recording area. Units (capping unit, suction unit, cleaning unit, etc.) are provided. Positioning of the carriage when moving the carriage to each of such units or when moving the carriage above the recording medium is performed by previously storing the position information of each unit or recording medium in a memory and provided on the carriage rail. The amount of movement of the carriage is detected using the obtained sensor, the position of the carriage is obtained from the amount of movement, and the carriage movement is stopped when the obtained position matches the position information stored in the memory. (For example, Patent Document 1).

Here, since the positioning of the carriage is also related to the ink ejection position, the positioning is very important and high-precision positioning is required.
However, in order to position the carriage with high accuracy, the structure becomes complicated, which increases the number of production line processes and costs. Moreover, since the structure cannot be changed after the assembly, it is not possible to cope with a positional shift of the component parts due to deterioration over time.
Attempts have also been made to eliminate such problems by controlling the operation of the carriage. For example, one that shifts the print position in accordance with the position of the recording medium detected by a sensor is known (for example, see Patent Document 1).
In addition, there is also known a method in which a distance from a nozzle to a recording medium is detected by a sensor, and ink ejection timing is controlled based on the detected distance (for example, see Patent Documents 2 and 3).

JP-A-6-340141 JP 2005-28715 A JP 2006-159843 A

However, the technique described in Patent Document 1 is effective in eliminating one misalignment such as the printing position of the recording medium, but positioning is performed at a plurality of different positions as in the ink jet recording apparatus. Insufficient for high accuracy. Moreover, since each unit differs in size, it is difficult to improve positioning accuracy using only the above technique.
In addition, the techniques described in Patent Documents 2 and 3 are effective when simply eliminating the positional deviation of the end of the recording medium, but the positioning can be performed at a plurality of different positions as in an ink jet recording apparatus. It is not enough for accuracy.

  SUMMARY An advantage of some aspects of the invention is that it provides an ink jet recording apparatus capable of improving the positioning accuracy of a carriage with respect to each unit or recording medium.

In order to solve the above problems, the invention described in claim 1
A carriage on which a head for ejecting ink is mounted;
A carriage rail for reciprocally supporting the carriage along one direction;
A drive unit for moving the carriage along the carriage rail;
A position detector for detecting position information of the carriage;
A plurality of unit portions provided at positions facing the carriage movement path, and used for maintenance of the head;
A unit position storage unit for storing the position of the unit unit;
A control unit that controls the drive unit to move the carriage to a position corresponding to the unit unit based on position information detected by the position detection unit, and to stop the carriage,
A unit distance storage unit that stores distance information between each of the unit units and the carriage, and a distance detection unit that moves with the carriage and detects distance information between each unit unit and the detector,
The control unit specifies a unit unit from the distance information detected by the distance detection unit and the distance information stored in the unit distance storage unit, and is detected by the position detection unit when detecting the distance information of the unit unit. The position information of the unit unit is acquired from the position information of the carriage, the acquired position information of the unit unit is stored in the unit position storage unit, and detected by the position information of the unit unit and the position detection unit. The carriage movement by the drive unit is controlled using the carriage position information obtained in the above.

According to a second aspect of the present invention, in the ink jet recording apparatus according to the first aspect,
The position information of each unit unit is acquired from the distance information detected by the distance detection unit and the position information of the carriage detected by the position detection unit when detecting the distance information of each unit unit, and the unit position storage A correction unit that rewrites the position information of the unit unit stored in the unit.

The invention according to claim 3 is the ink jet recording apparatus according to claim 1 or 2,
The unit distance storage unit stores range information of the installation position of each unit unit that is predicted to be provided with each unit unit, and distance threshold information for detecting the unit unit,
The control unit determines whether the detection signal detected by the distance detection unit exceeds a predetermined distance threshold within a range based on the range information, and exceeds the distance threshold based on the determination result. If it is determined that the unit portion exists within the range, the position information of the unit portion is acquired.

According to a fourth aspect of the present invention, in the ink jet recording apparatus according to the third aspect,
The unit distance storage unit stores width threshold information of the unit part for specifying the presence of the unit part,
The control unit determines whether or not the detection signal detected by the distance detection unit exceeds a predetermined width threshold value, and determines that the position information of the unit unit is detected when it is determined that the detection signal exceeds the width threshold value. It is characterized by acquiring.

The invention according to claim 5 is the ink jet recording apparatus according to claim 3 or 4,
The control unit performs acquisition of position information of the unit unit a plurality of times.

The invention according to claim 6 is the ink jet recording apparatus according to any one of claims 3 to 5, wherein
The unit distance storage unit stores a plurality of distance threshold information for each unit unit,
The control unit acquires position information of the unit unit using a plurality of distance threshold information.

The invention according to claim 7 is the inkjet recording apparatus according to any one of claims 4 to 6,
The unit distance storage unit stores a plurality of width threshold information for each unit unit,
The control unit acquires the position information of the unit unit using a plurality of width threshold information.

The invention according to claim 8 is the inkjet recording apparatus according to any one of claims 3 to 7,
In the range based on the range information, the control unit notifies the user by the notification unit when the distance detection unit does not detect the unit unit.

The invention according to claim 9 is the ink jet recording apparatus according to any one of claims 1 to 8,
The control unit stops the movement of the carriage when the distance information detected by the distance detection unit is a predetermined distance or more.

The invention according to claim 10 is the ink jet recording apparatus according to any one of claims 1 to 9,
Detecting the end of the recording medium placed on the transport unit by the distance detection unit;
The control unit is configured to perform image formation by driving the head when the carriage moves to the position of the detected end of the recording medium.

The invention according to claim 11 is the ink jet recording apparatus according to any one of claims 1 to 10,
The unit portion is a capping unit that moves downward so as to be separated from the head during recording, and moves upward to cover the nozzle of the head during non-recording,
The unit position storage unit includes a first inspection threshold value for detecting whether or not the capping unit is at a position covering the nozzles of the head, and whether or not the capping unit is at a position separated from the nozzles of the head. And a second inspection threshold value for detecting whether or not
The controller determines whether the detection signal detected by the distance detector exceeds a first inspection threshold and a second inspection threshold and inspects the operation of the capping unit. .

According to the first aspect of the present invention, the position of the unit portion at the present time in the state where the positional deviation has occurred even if the positional deviation due to aging or the like has occurred in any of the components constituting the ink jet recording apparatus. Can be directly detected and the carriage can be moved to that position, so that the carriage stop position does not shift with respect to the unit portion.
Therefore, the positioning accuracy of the carriage with respect to each unit and recording medium can be improved.

According to the second aspect of the present invention, even if the position of the unit portion is deviated, the position information of the unit portion stored in the storage portion can be rewritten by the correction portion. Stop position will not shift.
This makes it possible to correct the position information of each unit portion following changes in the configuration of the ink jet recording apparatus (such as aging deterioration), thus eliminating the need to readjust the position of each unit portion.

  According to the third aspect of the present invention, the control unit can detect the position exceeding the distance threshold in the detection signal detected by the distance detection unit as the presence position of the unit unit. It is possible to determine the carriage stop position with respect to the unit portion only by determining whether or not it has been.

According to the fourth aspect of the present invention, the control unit can specify the unit unit in more detail based on whether or not the width threshold is exceeded in the detection signal detected by the distance detection unit. Even if there are equal different unit parts, the unit part can be specified.
As a result, the carriage stop position can be acquired with higher accuracy than when the unit portion is detected using only the distance threshold.

  According to the fifth aspect of the present invention, it is possible to suppress erroneous detection of the acquired position information of the unit, and to improve reliability.

  According to the sixth aspect of the present invention, even when there are a plurality of unit parts having similar shapes, the unit parts can be specified using a plurality of distance threshold values, and the position information can be obtained with high accuracy. Can be acquired.

  According to the seventh aspect of the present invention, even when there are a plurality of similar-shaped unit parts, the unit parts can be specified using a plurality of width threshold values, and the position information can be obtained with high accuracy. Can be acquired.

  According to the eighth aspect of the present invention, when the unit part does not exist within the range where the unit part is predicted to exist, the notification unit notifies the user, so that the user can immediately cope with the distance. False detection of the detection unit can be suppressed.

According to the ninth aspect of the present invention, the carriage can be stopped when there is an obstacle in the movement path of the carriage, or when a large wrinkle or the like is formed on the recording medium. Detection can be suppressed.
Thereby, it can be used as a foreign matter detection device and a wrinkle detection device in the carriage movement path.

According to the invention described in claim 10, it is possible to detect the print start position on the recording medium.
Therefore, it is possible to prevent the printing position from being shifted with respect to the recording medium.

According to the invention described in claim 11, the state of the capping unit is grasped by determining whether or not the detection signal detected by the distance detection unit exceeds the first inspection threshold and the second inspection threshold. can do.
Thereby, it can be used as an operation inspection device for a capping unit, that is, a cap attachment / detachment inspection device.

1 is a perspective view showing an outline of an ink jet recording apparatus. The figure which shows arrangement | positioning with a recording medium and a unit part. The block diagram which shows the structure regarding a control part. The graph which shows the output characteristic of a distance detection part. The figure explaining the detection method of the unit part by a distance detection part. The figure which shows the example of the distance threshold value memorize | stored in the memory | storage part, and a width | variety threshold value. The flowchart explaining correction | amendment of the positional information on a unit part. (A) is a figure which shows the outline of the detection signal explaining correction | amendment of the positional information on a unit part, (b) is a figure which shows the specific example about correction | amendment of the positional information on a unit part. (A) is a figure explaining the method to detect a unit part from the detection start position of a unit part, (b) is a figure explaining the method of forming a recessed part in a unit part and detecting a unit part, (c) is a unit The figure explaining the method of providing a detection body in a part and detecting a unit part. The figure explaining the method of detecting a unit part using a plurality of distance thresholds and width thresholds. 3A and 3B are diagrams illustrating a method for detecting an end portion of a recording medium using a distance detection unit. 6A and 6B are diagrams illustrating a method for detecting wrinkles on a recording medium using a distance detection unit. The figure explaining the method to test | inspect the state of a capping unit using a distance detection part.

Hereinafter, the ink jet recording apparatus will be described with reference to the drawings. Specifically, the ink jet recording apparatus is an ink jet printer.
As shown in FIGS. 1 to 3, the inkjet printer 100 includes a transport unit 1, a carriage rail 2, a carriage 3, a head 4, a drive unit 5, a position detection unit 6, a unit unit 7 (see FIG. 2), and a distance detection unit. 8, the display part 9 (refer FIG. 3) and the control part 10 (refer FIG. 3) are provided.

  The transport unit 1 transports the recording medium S on which an image is formed below the head 4. The conveyance unit 1 is configured such that the conveyance belt moves in a direction Y orthogonal to the movement direction (X direction) of the carriage 3 by driving a motor (not shown). The upper surface of the conveyor belt is formed in a size that allows the recording medium S to be placed and supported.

  The carriage rail 2 is provided on a casing (frame) of the inkjet recording apparatus 100. The carriage rail 2 is arranged so as to straddle the conveyance unit 1, and the longitudinal direction X is arranged along a direction orthogonal to the conveyance direction Y of the recording medium S by the conveyance unit 1. The carriage rail 2 is formed to be longer than the width of the mounting area of the recording medium S so that the carriage 3 can move in the entire width direction (X direction) of the recording medium S.

The carriage 3 is supported by the carriage rail 2. The carriage 3 is supported by the carriage rail 2 so as to be reciprocally movable along the longitudinal direction (X direction) of the carriage rail 2.
A head 4 for ejecting ink is mounted on the carriage 3. The head 4 is individually provided for each of a plurality of color inks. The head 4 is provided corresponding to each color such as yellow (Y), magenta (M), cyan (C), and black (K), for example, and each head 4 has a nozzle at a position facing the recording medium S. Is formed. An image is formed on the recording medium S by ejecting droplets of ink from the nozzles.

The drive unit 5 is a mechanism for moving the carriage 3 along the carriage rail 2. The drive unit 5 includes a motor 51, a main driving roller 52, a driven roller 53, and a belt 54.
The motor 51 is provided at one end of the carriage rail 2. The output shaft is configured to rotate by energization, and a main driving roller 52 is provided on the output shaft. The main driving roller 52 is fixed to the output shaft, and rotates around the shaft as the output shaft rotates.
The driven roller 53 is rotatably provided at the other end of the carriage rail 2.
The belt 54 is hung on the main driving roller 52 and the driven roller 53. The carriage 3 is attached to the belt 54.
Therefore, when the motor 51 is driven, the output shaft rotates and the main driving roller 52 also rotates around the shaft. As the main driving roller 52 rotates, the belt 54 also rotates between the main driving roller 52 and the driven roller 53. As a result, the carriage 3 attached to the belt 54 also moves between the main driving roller 52 and the driven roller 53. Here, the carriage 3 can be reciprocated by rotating the motor 51 forward and backward.

The position detector 6 is provided along the longitudinal direction of the carriage rail 2. The position detection unit 6 is a linear sensor that detects position information of the carriage 3, outputs a position sensor signal when the carriage 3 moves, and detects the position of the carriage 3 based on the movement distance from the origin position of the carriage 3. To do.
The position detection unit 6 is not limited to a linear sensor, and may be a rotary sensor. Further, the motor 51 of the drive unit 5 may be an optical sensor or a motor with a magnetic sensor, and this sensor may be the position detection unit 6.

The unit portion 7 is mainly used during maintenance of the head 4. As shown in FIG. 2, the unit section 7 includes a capping unit 71 that performs capping of the nozzles of the head 4, a discharge unit 72 that performs preliminary discharge from the nozzles of the head 4, a nozzle missing detection unit 73 that detects nozzle missing, and a head 4, a cleaning unit 74 for cleaning 4, a suction unit 75 for sucking unnecessary ink from the nozzles and air that has entered the head 4. Each of these units is disposed at a position facing the movement path of the carriage 3.
The capping unit 71 is a moisturizing cap that covers the nozzles in order to prevent the nozzles from drying during non-recording. The moisturizing cap moves downward so as to be separated from the head 4 during recording, and moves upward to cover the nozzles of the head 4 during non-recording.
The discharge unit 72 is a place for discharging ink, and specifically, is a discharge groove.
The nozzle missing detection unit 73 includes a light emitting unit that emits laser light and a light receiving unit that receives the laser light emitted from the light emitting unit, and the ink ejected from the nozzle passes through the light emission path of the laser light. Arranged to be able to. Then, it is possible to check whether or not there is an ink discharge state, specifically, whether or not a nozzle is missing, based on whether or not the light receiving unit has received laser light. That is, when the light receiving unit receives the laser beam, the laser beam is not blocked by the ink, so that it is possible to detect that the nozzle has an ink ejection failure.
The cleaning unit 74 is for wiping off ink adhering to the nozzle surface of the head 4 with a blade or a roller.
The suction unit 75 sucks unnecessary ink from the head 4 or sucks air that has entered the head 4 when the head 4 is cleaned.

The distance detection unit 8 is provided in the carriage 3 and moves along the longitudinal direction of the carriage rail 2 together with the carriage 3. The distance detection unit 8 detects distance information between the unit units 71 to 75 and the detection unit 8.
The distance detection unit 8 is an optical distance sensor that detects the distance to the unit unit 7 by using the light projection signal and the light intensity of the light reception signal reflected from the unit unit 7 that is a light projection object. A distance detection signal having a corresponding voltage value is output.
FIG. 4 shows the output characteristics of the distance detector 8. The distance detection unit 8 detects a constant voltage value when the output voltage value increases as the distance to the unit unit 7 decreases. When the distance detection unit 8 is outside the detection range, that is, too close to or away from the certain distance range.
The distance detection unit 8 can also use an ultrasonic sensor whose output voltage value changes according to the reflection time of the ultrasonic wave, in addition to the above-described sensor using light reflection.

  As shown in FIG. 3, the display unit 9 displays information to be notified to the user regarding the state of the inkjet recording apparatus 100. That is, the display unit 9 functions as a notification unit. The display unit 9 is provided in a place where it does not operate like the carriage rail 2.

The control unit 10 controls driving of each unit of the inkjet recording apparatus 100, such as converting image data of an image to be recorded on the recording medium S input from an external device into data corresponding to each nozzle of the head 4.
As shown in FIG. 3, the control unit 10 includes a general-purpose computer in which a CPU, a ROM, a RAM, an input / output interface and the like are connected to a bus. The control unit 10 includes a transport unit 1, a drive unit 5, a position A detection unit 6, a unit unit 7, a distance detection unit 8, a display unit 9, a storage unit 11, and the like are connected.

The storage unit 11 is composed of a data rewritable EEPROM or the like.
The storage unit 11 stores position information of each of the unit units 71 to 75, and the storage unit 11 constitutes a unit position storage unit. Here, the position information of the unit section 7 is information (a so-called position table) regarding the distance from the reference position of the carriage 3. That is, the distance that the carriage 3 moves from the reference position so that the carriage 3 faces the unit portion 7 is stored as position information. The reference position of the carriage 3 may be any position as long as the position of the unit unit 7 can be specified from one reference position.
As shown in FIG. 5 and FIG. 6, the storage unit 11 is assumed to be provided with the unit unit 7, the range information of the installation position of the unit unit 7, and the distance threshold information for detecting the unit unit 7. And the width threshold value information of the unit part 7 for specifying the unit part 7 in more detail is stored. That is, the storage unit 11 has a configuration as a unit distance storage unit that stores the distance threshold information.

As shown in FIG. 5, the range information of the installation position of the unit unit 7 is information related to the region used for determining whether or not the unit unit 7 is included in the distance detection signal detected by the distance detection unit 8. It is. That is, the control unit 10 uses only the voltage value of the distance detection signal in the range included in the range information among the distance detection signals detected by the distance detection unit 8 for the determination, and the distance detection that does not belong to the range. The signal is not adopted for determining the presence or absence of the unit unit 7 by the control unit 10.
Note that the range information is a range that is slightly larger than the arrangement area of the unit section 7 in consideration of a margin such as a positional deviation in the arrangement position range of the unit section 7.

As shown in FIG. 5, the distance threshold information is the minimum necessary for the unit unit 7 when determining whether or not the distance detection signal within the range based on the range information is the unit unit 7 detected. This is the threshold value of the signal corresponding to the distance. That is, if the distance detection signal exceeds the distance threshold value, it can be determined that the unit unit 7 exists in the range, and if the distance detection signal does not exceed the distance threshold value, the unit unit 7 does not exist in the range. It will be. The distance threshold may be set to only the minimum distance (lower limit value) necessary for recognizing that the unit unit 7 is present, but if an obstacle is attached to the upper part of the unit unit 7, Since the carriage 3 may collide, in order to avoid this, it is better to provide a threshold for the upper limit of the distance.
Specifically, as shown in FIG. 6, the distance threshold of the capping unit 71 is “100 to 105”, the distance threshold of the discharge unit 72 is “90 to 95” with the bottom surface of the unit unit 7 as the reference position, and the nozzle missing detection The unit distance threshold is “90 to 95”, the cleaning unit 74 distance threshold is “80 to 85”, and the suction unit 75 distance threshold is “100 to 105”.

The width threshold information is a threshold for the width of the unit unit 7 used for specifying the unit unit 7 in more detail. That is, since there may be a case where there are a plurality of places with the same distance in one unit portion 7, it is used to determine which position of the unit portion 7 is used as position information in such a case.
Specifically, as shown in FIG. 6, the width threshold of the capping unit 71 is “40 to 50”, the width threshold of the discharge unit 72 is “10 to 15”, and the width threshold of the nozzle missing detection unit is “15 to 20”. ”, The width threshold value of the cleaning unit 74 is stored as“ 25-30 ”, and the width threshold value of the suction unit 75 is stored as“ 40-50 ”.
In the present embodiment, as described above, the unit unit 7 is described using the width threshold value information in order to specify in more detail, but such a configuration is not necessarily essential. That is, when the number of the unit units 7 is small, or when the unit units are spaced apart, the unit unit 7 may be specified only by the distance information described above.

The control unit 10 specifies the unit unit 7 from the distance information detected by the distance detection unit 8 and the distance information stored in the storage unit 11, and stores the position of the unit unit 7 specified in the storage unit 11, The movement of the carriage 3 by the drive unit 5 is controlled using the position information of the unit unit 7 and the position information of the carriage 3 detected by the position detection unit 6.
As shown in FIG. 5, the control unit 10 determines whether or not the distance detection signal detected by the distance detection unit 8 exceeds the distance threshold within a range where the unit unit 7 based on the range information is considered to exist. To do. And it is determined whether the width | variety of the unit part 7 calculated from the detected distance detection signal exceeds the width | variety threshold value. In this way, the range in which the unit portion 7 is searched is determined, and the unit portion 7 is specified using the distance and the width from the distance detection signal.
The control unit 10 specifies the unit unit 7 by the distance detection unit 8 and acquires the position information of the unit unit 7 by acquiring the position information of the unit unit 7 by the position detection unit 6. The acquired position information of each unit unit 7 is written in the storage unit 11 as the latest position information of the unit unit 7. The position information of the unit unit 7 already written in the storage unit 11 is overwritten with new data and updated. Thereby, the position information of the unit unit 7 can be corrected, and the control unit 10 functions as a correction unit.
The control unit 10 stops the carriage 3 based on the corrected position information of the unit unit 7.
The control part 10 can also acquire the position information of the unit part 7 a plurality of times by repeating this process a plurality of times. This is a preferable process for improving the correction accuracy of the position information.
When the distance detection unit 8 does not detect the unit unit 7 within the range based on the range information, the control unit 10 displays on the display unit 9 that the unit unit 7 does not exist within the range, and allows the user to Inform. Note that the notification to the user is not limited to display on the display unit 9, but may be notification by an alarm sound or notification by turning on or blinking the light source.

<Correction of position information of each unit>
Next, correction processing of position information (hereinafter referred to as a position table) of each unit unit stored in the storage unit 11 will be described.
As shown in FIG. 7, before the carriage 3 is moved, it is before correction of the position table, so that the position table is set as an initial value state (step S101).
Next, under the control of the drive unit 5 by the control unit 10, the carriage 3 is moved along the carriage rail 2 and scanning of the unit unit 7 is started (step S102).
During the movement process of the carriage 3, the control unit 10 has a distance threshold value in which the voltage value of the distance detection signal detected by the distance detection unit 8 is stored in the storage unit 11 at a position based on the range information stored in the storage unit 11. It is determined whether or not the voltage value exceeds (step S103).

In step S103, the control unit 10 determines that the voltage value of the distance detection signal detected by the distance detection unit 8 exceeds the voltage value that is the distance threshold stored in the storage unit 11 (step S103: YES). The control unit 10 determines whether the position detected by the distance detection unit 8 and recognized as the unit unit 7 does not match the initial value of the position table, that is, whether a positional deviation has occurred. Is determined (step S104).
In step S103, the control unit 10 determines that the voltage value of the distance detection signal detected by the distance detection unit 8 does not exceed the voltage value serving as the distance threshold stored in the storage unit 11 (step S103: NO). ), The control unit 10 determines whether or not the scanning of the unit unit 7 has been completed (step S106).

In step S104, the control unit 10 determines that the position detected by the distance detection unit 8 and recognized as the unit unit 7 does not match the initial value of the position table (step S104: YES). The unit 10 corrects the position table at the position detected by the distance detection unit 8 (step S105).
In step S104, the control unit 10 determines that the position detected by the distance detection unit 8 and recognized as the unit unit 7 matches the initial value in the position table (step S104: NO). The unit 10 determines whether or not the scanning of the unit unit 7 has been completed (step S106).

  In step S106, when the control unit 10 determines that the scanning of the unit unit 7 has ended (step S106: YES), the control unit 10 ends the process. On the other hand, when the control unit 10 determines that the scanning of the unit unit 7 has not ended (step S106: NO), the control unit 10 returns to the process of step S103.

Here, the correction of the position table will be described with a specific example.
As shown in FIG. 8A, it is assumed that the distance detection signal detected by the distance detection unit 8 has a waveform like the uppermost stage. Assume that the initial position table stored in the storage unit 11 is the second-stage signal waveform.
Here, when the detection start position of the unit unit 7 by the distance detection unit 8 is used as a reference, the unit unit between the position of the unit unit 7 actually detected and the initial position table due to the positional deviation of each unit unit 7. It can be seen that 7 is detected at different positions.
In such a case, the control unit 10 corrects the position table so as to have the lowest waveform so that the position table becomes the detection start position of the distance detection signal detected by the distance detection unit 8.
As shown in FIG. 8B, the position of the capping unit 71 is “1000”, the position of the discharge unit 72 is “1500”, the position of the nozzle missing detection unit is “2000”, and the cleaning unit 74 is positioned relative to the reference position. When the position is “2500” and the position of the suction unit 75 is stored as “3000”, the position of the capping unit 71 detected by the distance detection unit 8 is “1100”, and the position of the discharge unit 72 is “1800”. When the position of the nozzle missing detection unit is “2200”, the position of the cleaning unit 74 is “2400”, and the position of the suction unit 75 is “2900”, the control unit 10 determines the positions of the unit units 71 to 75. Correct to the detected position.

In detecting the unit portion 7, as shown in FIG. 9A, the distance detecting portion 8 may detect a portion where the unit portion 7 is higher than the surroundings, but FIG. As shown in b), the concave portion 7b is formed in a part of the unit portion 7, and the distance of the bottom surface portion is formed at a completely different distance from the surroundings, so that the unit portion 7 can be specified. .
Further, as shown in FIG. 9C, by forming a convex portion on the upper surface of the unit portion 7 or attaching a detection object 7c, the distance to the upper surface portion is formed at a completely different distance from the surroundings. By doing so, the unit part 7 may be specified.

In addition, a plurality of distance threshold information and width threshold information are stored in the storage unit 11 for each unit unit 7, and the control unit 10 obtains position information of the unit unit 7 using the plurality of distance threshold information and width threshold information. You may make it do.
Specifically, as shown in FIG. 10, in the case where the unit portion 7A has a plurality of distances and widths, the detection region is divided for each portion having a different distance, and in one region, the distance threshold (1) Alternatively, the width threshold (1) may be used, and the distance threshold (2) and the width threshold (2) may be used in another region, and the unit portion 7A may be specified from these detection results.
By adopting such a method, the unit unit 7 can be specified using a plurality of distance thresholds and width thresholds even when there are a plurality of unit units 7 having a similar shape. Position information can be acquired more reliably.
Further, it is possible to prevent erroneous detection such as detecting the unit portion 7 at another position.

<Detection of edge of recording medium, detection of wrinkle of recording medium>
The distance detection unit 8 provided in the inkjet recording apparatus 100 is used to detect the distance of the unit unit 7 and acquire the position information of the unit unit 7, but as shown in FIG. The unit 8 may be used for edge detection of the recording medium S.
Specifically, the threshold range of the thickness (distance) of the recording medium S is stored in the storage unit 11, and the control unit 10 determines that the distance information detected by the distance detection unit 8 is within the threshold range. When it is determined that there is, the head 4 is driven to eject ink, and recording on the recording medium S is started.
As a result, the print start position on the recording medium S can be detected. That is, since the head 4 is driven to form an image for the first time when the carriage 3 moves to the end of the recording medium S, the recording position on the recording medium S does not shift.
Furthermore, as shown in FIG. 12, the recording unit 11 stores a threshold value of a distance at which wrinkles are generated in the recording medium S and an obstacle on the recording medium S is recognized. When it is determined that the distance information detected by the distance detection unit 8 has exceeded the threshold, the control unit 10 can also stop the drive of the drive unit 5 and immediately stop the movement of the carriage 3.
As described above, even when there is an obstacle in the movement path of the carriage 3 and a large wrinkle or the like is formed on the recording medium S, the carriage 3 is stopped by detecting the wrinkle or the obstacle with the distance detection unit 8. Thus, erroneous detection of the distance detector 8 can be suppressed.
Therefore, the distance detection unit 8 can also be used as a foreign matter detection device and a wrinkle detection device in the movement path of the carriage 3.

<Operation inspection of capping unit>
The distance detection unit 8 provided in the inkjet recording apparatus 100 is used to detect the distance of the unit unit 7 and acquire the position information of the unit unit 7, but as shown in FIG. The unit 8 may be used for the operation inspection of the capping unit 71.
Specifically, as shown in FIG. 13, a first inspection threshold value for detecting whether or not the moisture retaining cap of the capping unit 71 is in a position covering the nozzles of the head 4, and the capping unit 71 from the nozzles of the head 4. The storage unit 11 stores a second inspection threshold value for detecting whether or not the separated position is present.
That is, the first inspection threshold is a threshold for determining whether or not the moisture retaining cap of the capping unit 71 covers the nozzle during non-recording, and the second inspection threshold is the moisture retaining cap of the capping unit 71 during recording. Is a threshold value for determining whether or not is removed from the nozzle and retracted downward.
The control unit 10 determines whether the distance detection signal detected by the distance detection unit 8 exceeds the first inspection threshold and the second inspection threshold, specifies the position of the capping unit 71, and determines the capping unit 71. Inspect the operation.
Thereby, the control unit 10 grasps the state of the capping unit 71 by determining whether or not the distance detection signal detected by the distance detection unit 8 exceeds the first inspection threshold and the second inspection threshold. can do.
Therefore, the distance detection unit 8 can also be used as an operation inspection device for the capping unit 71, that is, a cap attachment / detachment inspection device.

<Action and effect>
As described above, according to the ink jet recording apparatus 100, the distance detection unit 8 is in a state in which a positional deviation has occurred even if a positional deviation has occurred due to aging degradation or the like in any of the components constituting the inkjet recording apparatus. Since the position of the unit unit 7 at this time is detected and the carriage 3 can be moved to that position, the stop position of the carriage 3 does not shift with respect to the unit unit 7.
Therefore, the positioning accuracy of the carriage 3 with respect to the unit portion 7 and the recording medium S can be improved.

Even if the position of the unit unit 7 is shifted, the position information (position table) of the unit unit 7 stored in the storage unit 11 can be rewritten by the control unit 10. The stop position will not shift.
As a result, the position information (position table) of the unit unit 7 can be corrected following changes in the configuration of the ink jet recording apparatus 100 (such as aging deterioration), and therefore the position of the unit unit 7 needs to be readjusted. Disappear.

Moreover, since the control part 10 can detect the position exceeding the distance threshold in the distance detection signal detected by the distance detection part 8 as the presence position of the unit part 7, it is determined whether or not the distance threshold is exceeded. Only the stop position of the carriage 3 can be determined with respect to the unit portion 7.
Moreover, since the control part 10 can specify the unit part 7 in more detail according to whether the width threshold value was exceeded in the distance detection signal detected by the distance detection part 8, the different unit parts 7 having the same distance. Even if there is a case, the unit portion 7 can be specified.
As a result, the stop position of the carriage 3 can be acquired with higher accuracy than when the unit unit 7 is detected using only the distance threshold.
In addition, by acquiring the position information of the unit unit 7 a plurality of times, it is possible to suppress erroneous detection of the acquired position information of the unit unit 7 and to improve reliability.

DESCRIPTION OF SYMBOLS 1 Conveyance part 2 Carriage rail 3 Carriage 4 Head 5 Drive part 6 Position detection part 7 Unit part 8 Distance detection part 9 Display part (notification part)
10 Control unit (correction unit)
11 Storage unit (unit position storage unit, unit distance storage unit)
71 Capping unit (unit part)
72 Discharge unit (unit part)
73 Nozzle missing detection unit (unit part)
74 Cleaning unit (unit part)
75 Suction unit (unit part)
100 Inkjet recording apparatus S Recording medium

Claims (11)

A carriage on which a head for ejecting ink is mounted;
A carriage rail for reciprocally supporting the carriage along one direction;
A drive unit for moving the carriage along the carriage rail;
A position detector for detecting position information of the carriage;
A plurality of unit portions provided at positions facing the carriage movement path, and used for maintenance of the head;
A unit position storage unit for storing the position of the unit unit;
A control unit that controls the drive unit to move the carriage to a position corresponding to the unit unit based on position information detected by the position detection unit, and to stop the carriage,
A unit distance storage unit that stores distance information between each of the unit units and the carriage, and a distance detection unit that moves with the carriage and detects distance information between each unit unit and the detector,
The control unit specifies a unit unit from the distance information detected by the distance detection unit and the distance information stored in the unit distance storage unit, and is detected by the position detection unit when detecting the distance information of the unit unit. The position information of the unit unit is acquired from the position information of the carriage, the acquired position information of the unit unit is stored in the unit position storage unit, and detected by the position information of the unit unit and the position detection unit. An inkjet recording apparatus, wherein carriage movement by the drive unit is controlled using the carriage position information obtained in (1).   The position information of each unit unit is acquired from the distance information detected by the distance detection unit and the position information of the carriage detected by the position detection unit when detecting the distance information of each unit unit, and the unit position storage The inkjet recording apparatus according to claim 1, further comprising a correction unit that rewrites position information of the unit unit stored in the unit. The unit distance storage unit stores range information of the installation position of each unit unit that is predicted to be provided with each unit unit, and distance threshold information for detecting the unit unit,
The control unit determines whether the detection signal detected by the distance detection unit exceeds a predetermined distance threshold within a range based on the range information, and exceeds the distance threshold based on the determination result. 3. The inkjet recording apparatus according to claim 1, wherein, when it is determined that the unit unit is present within the range, the position information of the unit unit is acquired. The unit distance storage unit stores width threshold information of the unit part for specifying the presence of the unit part,
The control unit determines whether or not the detection signal detected by the distance detection unit exceeds a predetermined width threshold value, and determines that the position information of the unit unit is detected when it is determined that the detection signal exceeds the width threshold value. The inkjet recording apparatus according to claim 3, wherein the inkjet recording apparatus is acquired.   5. The inkjet recording apparatus according to claim 3, wherein the control unit acquires position information of the unit unit a plurality of times. The unit distance storage unit stores a plurality of distance threshold information for each unit unit,
The ink jet recording apparatus according to claim 3, wherein the control unit acquires position information of the unit unit using a plurality of distance threshold information. The unit distance storage unit stores a plurality of width threshold information for each unit unit,
The inkjet control apparatus according to claim 4, wherein the control unit acquires position information of the unit unit using a plurality of width threshold information.   The said control part alert | reports to a user by an alerting | reporting part, when the said distance detection part does not detect the said unit part within the range based on the said range information, The one of Claims 3-7 The ink jet recording apparatus according to one item.   The said control part stops the movement of the said carriage, when the distance information detected by the said distance detection part is more than predetermined value distance, The movement as described in any one of Claims 1-8 characterized by the above-mentioned. Inkjet recording device. Detecting the end of the recording medium placed on the transport unit by the distance detection unit;
10. The image forming apparatus according to claim 1, wherein the control unit drives the head to form an image when the carriage moves to the position of the end of the detected recording medium. Inkjet recording apparatus. The unit portion is a capping unit that moves downward so as to be separated from the head during recording, and moves upward to cover the nozzle of the head during non-recording,
The unit position storage unit includes a first inspection threshold value for detecting whether or not the capping unit is at a position covering the nozzles of the head, and whether or not the capping unit is at a position separated from the nozzles of the head. And a second inspection threshold value for detecting whether or not
The controller determines whether the detection signal detected by the distance detector exceeds a first inspection threshold and a second inspection threshold and inspects the operation of the capping unit. The ink jet recording apparatus according to claim 1.

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