JP2000158740A - Carriage driving method and ink jet recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance accuracy of the stopping position of a carriage when a recording head mounted on the carriage is capped without causing any increase in size and to prevent the operating time being elapsed before stopping the carriage from becoming redundant. SOLUTION: A carriage 4 is stopped temporarily at an advance nearby position different from a target position and a pin 3 is pressed against the carriage. The carriage is then moved at a micro speed from the advance position toward the target position and positional displacement of the pin following up the profile of the carriage is detected during movement thereof thus stopping the carriage with the unit step accuracy of a stepping motor for driving the carriage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a carriage driving method using a stepping motor for driving a carriage, and an ink jet recording apparatus employing the carriage driving method.

[0002]

2. Description of the Related Art A recording device having functions such as a printer, a copying machine, and a facsimile, or a recording device used as an output device such as a composite electronic device including a computer or a word processor, or a workstation, is based on paper based on the recording information. An image (including characters and symbols) is recorded on a recording material (recording medium) such as a cloth, a plastic sheet, and an OHP sheet. The recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type and the like according to a recording method.

In a serial type recording apparatus which performs recording while performing main scanning in a direction intersecting a conveying direction (paper feeding direction, sub-scanning direction) of the recording material, the serial type recording device is mounted on a carriage which moves along the recording material. An image is recorded (main scanning) by a recording unit (recording head), a predetermined amount of paper is fed (pitch conveyance as sub-scanning) after one line of recording is completed, and then the recording material is stopped again. On the other hand, by repeating the operation of recording (main scanning) the image of the next row, the recording of the entire recording material is performed. On the other hand, in a line type recording apparatus that performs recording only in the sub-scanning direction of the recording material, the recording material is set at a predetermined recording position, and recording is performed for one line at a time. Is repeated, and the recording of the next line is collectively performed, thereby recording the entire recording material.

Among them, an ink jet type recording apparatus (ink jet recording apparatus) performs recording by discharging ink from a recording means (recording head) to a recording material, so that the recording means can be easily made compact. High-definition images can be recorded at high speed, and can be recorded on plain paper without requiring special processing, running costs are low, and the non-impact method reduces noise,
In addition, there is an advantage that it is easy to record a color image using various types of inks (for example, color inks).

As an energy generating element for generating energy used for discharging ink from a discharge port of an ink jet recording head, an element using an electromechanical transducer such as a piezo element, or heating by irradiating an electromagnetic wave such as a laser. Then, an ink droplet is ejected by the heat generation function, or a liquid is heated by an electrothermal converter having a heat generating resistor. Among them, an ink jet type recording means (recording head) that discharges ink as droplets using thermal energy can perform high-resolution recording because discharge ports can be arranged at high density. In particular, among them, a recording head using an electrothermal transducer element as an energy generating element can be easily miniaturized, and IC technology and micro-machining technology, which are remarkable in recent advances in technology in the field of semiconductors and remarkable improvement in reliability. This is advantageous because the advantages of the above can be fully utilized, high-density mounting is easy, and the manufacturing cost is low.

There are various requirements for the material of the recording material. In recent years, developments have been made to meet these requirements, and paper (including thin paper and processed paper) which is a general recording material has been developed.
In addition to paper and resin thin plates (OHP, etc.), recording devices using cloth, leather, nonwoven fabric, metal, or the like as a recording material have come to be used.

[0007] In a serial type ink jet recording apparatus, recording is generally performed by reciprocating (scanning) a carriage equipped with a recording head for discharging ink toward a recording material along the recording material. . The carriage is guided and supported so as to be able to reciprocate along a straight shaft or rail, and is generally driven directly by a belt or the like from a motor as a drive source, and a DC motor or a stepping motor is used as a motor type. Have been.

[0008] In the case of a DC motor, it is necessary to perform closed drove control using an encoder or the like for position control, which causes problems such as control complexity. In the case of a stepping motor, open loop control is easily performed. For this reason, a stepping motor is often used. When a stepping motor is used, the drive of the carriage is controlled based on the position where the sensor output of the non-contact optical sensor disposed within the movement range of the carriage has changed, and the subsequent operation (movement) and The control of the position is performed by calculating the number of drive pulses from the reference position.

In addition, in an ink jet recording apparatus, dust (paper powder, etc.) and fixed (dry) ink around the discharge port of the recording head are removed, and ink drops and bubbles in the discharge port are prevented. A suction recovery process of sucking ink from the discharge port by applying a negative pressure while the discharge port is covered with a cap (capping), and a wiping (cleaning) process of wiping and cleaning the discharge port surface with a blade or the like. Maintenance is required. In this case, the carriage is stopped at a predetermined position outside the recording range, the maintenance mechanism for performing capping or wiping is aligned with the carriage, and capping or wiping is performed on the recording head mounted on the carriage. There is a need.

At this time, the carriage stops at a position (capping position or wiping position) moved from the reference position by the number of pulses determined in the apparatus design. However, the dimensional tolerance of each part is accumulated, and the sensor is used as a reference. Due to variations in accuracy or the like, displacement of the stop position of the carriage is likely to occur. When the displacement occurs, the cap does not adhere to the recording head to cause suction failure, or the wiper wipes (wipes) a different portion, which adversely affects the maintenance operation.

If there is sufficient structural margin between the recording head and the cap or the wiper, it is possible to allow the displacement, but providing such a margin is a countermeasure for reducing the size and weight of the apparatus. In general, it is necessary to provide a means for preventing displacement. For example, in order to obtain a configuration that allows a displacement of the capping position, a sufficiently wide flat surface is provided around the discharge port of the recording head so as to allow the variation in accuracy of related components, and the position is adjusted. It is necessary to set the size so that the cap can be stuck to the flat surface even if it is shifted, and to finish the flatness of this flat surface with high precision in order to prevent leakage.

FIG. 8 is a schematic longitudinal sectional view showing an example of a means for preventing displacement of capping. In FIG. 8, a tapered pin 3 is provided on a cap holder 2 on which a cap 1 is mounted, and a reciprocating carriage 4 is provided with a hole 5 capable of engaging (fitting) with the pin 3.
When the carriage 4 stops at a predetermined position (capping position), the cap 1 is urged toward the recording head 7 by the spring 6 together with the cap holder 2. The pin 3 of the cap holder 2 is fitted into the hole 5 of the carriage 4 along the tapered shape formed at the tip, and as a result, the relative position between the cap 1 and the recording head 7 is determined. In that case, in order to improve the accuracy of the relative position, the cap 1
It is necessary to provide a mechanism for assisting the recording head 7 to uniformly contact the recording head 7 without being bent or inclined with respect to the recording head 7.

FIG. 9 is a schematic longitudinal sectional view showing another example of the capping displacement preventing means. In FIG. 9, when the carriage 4 moves in the direction of the arrow, the recording head 7 is moved.
The right side in the figure abuts on the engaging surface of the cap holder 2, and the cap mechanism 2 is lifted up in the upper right direction in the figure by a link mechanism. In the configuration of FIG. 8, the relative position between the recording head 7 and the cap 2 in the carriage moving direction is defined by the contact between the recording head 7 and the cap holder 2. In most cases, the operation of wiping the ejection port surface of the recording head 7 is performed by moving the carriage 4 with the wiper protruding to a position where the wiper projects to the position where the ejection port surface of the recording head 7 interferes. The outlet surface is configured to be wiped, and such a configuration can allow a displacement during wiping.

[0014]

However, in the carriage driving method as described with reference to FIGS. 8 and 9, a deviation is anticipated in advance in order to eliminate the need for relative positioning between the recording head and the cap. However, in the case where the configuration has a margin, there is a disadvantage that the entire recording apparatus including the recording head is apt to be enlarged. Further, if the movable member arranged on the printing apparatus main body is configured to follow the movement of the carriage at the time of capping or the like, the ejection openings of the print head tend to be capped from an oblique direction.
There is an inconvenience that the contact (adhesion) accuracy of the cap cannot be improved and the cap is easily distorted.

Further, the position of the carriage may be shifted due to the cap pressing force at the time of capping.
The wiper may be wiped in the direction perpendicular to the carriage scanning direction in consideration of the configuration of the print head and the characteristics of the ink used. In such a case, the ejection port of the print head may be used. Fine adjustment may be required to match the high-density array.

The present invention has been made in view of such technical problems, and an object of the present invention is to provide a method for capping or wiping recording means mounted on a carriage without increasing the size of the apparatus. An object of the present invention is to provide a carriage driving method and an ink jet recording apparatus capable of improving the accuracy of the stop position of the carriage and preventing redundant operation time until the carriage is stopped.

[0017]

According to a first aspect of the present invention, there is provided a carriage driving method using a stepping motor for driving a carriage, wherein the carriage is stopped at a target position. After stopping the carriage at a pre-position different from the target position, a pin is pressed against the carriage from a direction substantially perpendicular to the carriage moving direction, and then the carriage is moved from the pre-position to the target position. The carriage is stopped at the target position with the accuracy of the driving step of the stepping motor by detecting the displacement of the pin following the shape of the pin.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the pin is engaged with a step or a hole provided in the carriage at the target position, and the displacement of the pin is detected. Then, the target position at which the carriage is stopped is stored by the number of drive pulses of the stepping motor, and when the carriage is stopped at the pre-position next time, the number of drive pulses to the target position after pressing the pin is calculated. Or, when the number of drive pulses to the target position after pressing the pin is reduced, the number of drive pulses to move from the pre-position to the target position exceeds the specified number of pulses. If the displacement of the pin is not detected, the position reference of the carriage is calculated again, and the advance position farther from the target position than the previous position where the displacement of the pin was not detected is obtained. After pressing the pin carriage is stopped by a structure for moving the carriage, it is to achieve a more efficient purpose.

According to a fifth aspect of the present invention, there is provided an ink-jet recording apparatus in which recording means is mounted on a carriage driven by a stepping motor, and ink is discharged from the recording means onto a recording material to perform recording. In the inkjet recording apparatus to be performed, when stopping the carriage at the target position, the carriage is stopped at a pre-position different from the target position, and then a pin is pressed against the carriage from a direction substantially perpendicular to the carriage moving direction, and then the carriage is moved. The carriage is moved from the pre-position to the target position, and the carriage is stopped at the target position with the accuracy of the driving step of the stepping motor by detecting the displacement of a pin that follows the shape of the carriage during this movement. And

According to a sixth aspect of the present invention, in addition to the configuration of the fifth aspect, the target position is a position for performing maintenance on recording means such as capping or wiping of the recording means. A configuration in which a pin is engaged with a step or a hole provided in the carriage, a target position where the displacement of the pin is detected and the carriage is stopped is stored by the number of drive pulses of the stepping motor, and then the carriage is When stopping at the pre-position, a configuration for reducing the number of drive pulses to the target position after pressing the pin, when reducing the number of drive pulses to the target position after pressing the pin, When the displacement of the pin is not detected even when the number of pulses for moving from the pre-position to the target position is exceeded. A configuration in which the position reference of the carriage is obtained again, the carriage is stopped at a pre-position farther from the target position than the previous time when the displacement of the pin was not detected, and the carriage is moved after pressing the pin, or Is engaged with a hole provided in the carriage so as to serve also as a positioning means for preventing the carriage from being displaced from a capping position covering the discharge port of the recording means during non-recording, thereby achieving the above object more efficiently. To achieve.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. Throughout the drawings, the same reference numerals indicate the same or corresponding parts. FIG. 1 is a schematic longitudinal sectional view showing the configuration of a main part of an embodiment of an ink jet recording apparatus to which the present invention is applied. In FIG. 1, a carriage 4 has a guide shaft (rail) 1 installed in the width direction of the printing apparatus main body.
It is guided and supported so as to be able to reciprocate along 6, and is driven via a belt 9 by a stepping motor 8 as a drive source. The resolution in the moving direction (scanning direction) of the carriage 4 is, for example, 0.127 (mm / step). A recording means (recording head) 7 is positioned and mounted on the carriage 4.

Adjacent to the movement path of the carriage 4,
An optical sensor 10 is provided. The optical sensor 10 is a carriage optical sensor for detecting the carriage 4 and setting a reference for the operating position of the carriage. The variation in the distance between the position of the carriage optical sensor 10 and the center position of the ejection port of the recording head 7 is as follows:
When the detection accuracy of the optical sensor 10 and the assembly accuracy of the carriage 4 and the recording head 7 are added and accumulated,
For example, it is about 1.789 mm, which corresponds to about 15 steps of the stepping motor 8.

The recording means (recording head) 7 is an ink jet recording head for selectively discharging ink from a plurality of discharge ports to perform recording by applying energy according to a recording signal. The recording head 7 is an ink jet recording means for discharging ink using thermal energy, and includes an electrothermal converter for generating thermal energy. Further, the recording head 7 performs recording by discharging ink from a discharge port using a pressure change generated by growth and shrinkage of bubbles caused by film boiling caused by thermal energy applied by the electrothermal transducer. It is. The electrothermal transducer is provided corresponding to each of the ejection ports, and discharges ink from the corresponding ejection port by applying a pulse voltage to the corresponding electrothermal transducer in accordance with a recording signal.

FIG. 7 is a partial perspective view schematically showing the structure of an ink ejection section (one ejection port array) of the recording means (recording head) 7. In FIG. 7, a recording material (recording paper, etc.)
A plurality of discharge ports 82 are formed at a predetermined pitch on an ink discharge surface 81 facing the ink discharge surface 81 at a predetermined gap (for example, about 0.3 to 2.0 mm). An electrothermal converter (heating resistor or the like) 85 for generating energy for ink ejection is provided along a wall surface of each liquid passage 84 communicating with the outlet 82.

In this embodiment, the recording head 7 is mounted on the carriage 4 so that the ejection openings 82 are arranged in a direction intersecting the main scanning movement direction (the movement direction of the carriage 4). . In this manner, the corresponding electrothermal transducer 85 is driven (pulse voltage is applied) based on the image signal or the ejection signal to cause the ink in the liquid path 84 to boil, and the pressure generated at that time causes the ink from the ejection port 82 to pass through the ejection port 82. A recording means (recording head) 7 for discharging droplets is configured.

In FIG. 1, a maintenance mechanism of the recording head 7 (in the illustrated example, attached to the cap holder 2) is located at a predetermined position within the moving range of the carriage 4 and outside the recording area. In this target position, the recording head can be properly capped by advancing the cap holder 2 toward the recording head 7 so as to abut the same. When you come to the position,
The pin 3 is fitted and engaged with the hole 5 of the carriage so that the carriage 4 is properly positioned and held at a target position.

FIGS. 2 to 4 are schematic elevational views showing a carriage positioning mechanism mounted on the ink jet recording apparatus of FIG. 1, and FIG. 2 shows a state in which the carriage positioning mechanism is in a position-restricted state (downward retracted state). , And FIG.
FIG. 4 shows a state in which the carriage positioning mechanism is in the released state (upwardly biased state) and the carriage is at the target position. FIG. 4 shows that the carriage is in the pre-position and the carriage positioning mechanism is in the released state (upwardly biased state). Shows when

1 to 4, a hole 5 is provided on the lower surface of the carriage 4. As shown in FIG. On the recording device body side,
An arm 12 that is rotatably supported about a center 1 is provided. One end (upward end in the drawing) of the arm 12 engages (fits) with the hole 5 of the carriage 4.
A possible pin (or pin part) 3 is provided. Also,
A plate-shaped protruding light-shielding portion 14 for shielding the arm optical sensor 13 from light is provided at the other end (the downward end in the drawing) of the arm 12. Further, a rotary cam 15 is disposed at a position adjacent to the arm 12.

The rotary cam 15 has an operating position for holding the arm 12 in a position regulating state (retracted downward) as shown in FIGS. 1 and 2, and an arm 1 as shown in FIGS.
2 is rotated so as to take a separated position for bringing the second member 2 into a released state (in the illustrated example, an upwardly urged state urged upward by a spring 6). When the carriage 4 is separated from the capping position as shown in FIG. 1, the arm 12 is in the position regulating state (retracted downward) as shown in FIG.
Is held at a lower position separated from the movement path (scanning position) of the carriage 4, and the arm optical sensor 13 is shielded from light by the protruding light shielding unit 14 and is in an OFF state.

FIGS. 3 and 4 show a state in which the arm 12 is in a released state separated from the cam 15. In this state, the arm 12 is urged upward by the elastic force of the spring 6. That is, it is in the upwardly biased state. In this released state (upwardly biased state), the arm 12 is urged upward by the spring 6, and therefore the pin 3 is also urged upward. Then, when the carriage 4 reaches a target position such as a capping position, the pin 3 at the tip of the arm 12 is fitted into the hole 5 of the carriage 4 as shown in FIG. In the state shown in FIG. 3, since the tip of the arm 12 is lifted up by fitting the pin 3 and the hole 5, the arm 1
The two projecting light shielding portions 14 are separated from the arm optical sensor 13 and the optical sensor 13 is turned on.

Even when the arm 12 is in the released state (upwardly biased state), the carriage 4 has not yet reached the target position and is in the vicinity (for example, between the pre-position and the target position). As shown in FIG.
The pin 3 at the end of the carriage 4 cannot be fitted into the hole 5 of the carriage 4 and comes into contact with the flat surface (lower surface) of the carriage 4. In this state, as shown in FIG. 4, the optical sensor for arm 13 is still light-shielded by the protruding light-shielding portion 14 and is in an OFF state. And the arm 1
2 is in the released state (upwardly biased state) and the pins 3 are engaged (fitted) in the holes 5 of the carriage 4, the carriage 4 is in a maintenance mechanism (capping of the recording head 7). Mechanism or wiping mechanism) and is held at the target position (correct operating position).

FIG. 5 is a flowchart showing an operation of aligning the carriage 4 with the capping mechanism as an example of the case where the carriage 4 is aligned with the target position. Here, a case where the carriage 4 moves leftward in the figure is shown. In FIG. 5, first, based on a reference position [point O in (a)] of the carriage 4 detected by the carriage optical sensor 10, the carriage 4 is moved from the reference position O to a target position (in this case, design theory). The number of driving steps X of the stepping motor 8 until reaching the upper capping position) is given.

When the operation of positioning the carriage 4 is started, that is, when the operation of stopping the carriage 4 at the target position is started, first, a pre-position different from the target position is set, and the carriage 4 is moved. Move to this pre-position. The pre-position is set at a position near the position where the pin 3 never fits into the hole 5 of the carriage 4 and is close to the position where the pin 3 fits into the hole 5. Specifically, for example, as shown in (a) of FIG. 5, when the number of motor driving steps from the reference position to the target position is X,
The number of motor drive steps from the reference position to the pre-position is selected at the position of (X + 16) steps. Then, the carriage 4 is moved to the left (X + 16) step position in the figure. When reaching the pre-position, the carriage 4 is stopped, and then the arm 1 on the recording apparatus main body side is stopped.
2 is moved (rotated) from the position restricting state (downward retracted state) of FIG. 2 to the released state (upwardly biased state) of FIG. 4, and the pin 3 of the arm 12 is moved as shown in FIG. Is pressed against the flat surface of the carriage 4.

Next, the carriage 4 is moved at a very low speed from the (X + 16) step position set at the pre-position to the X step position which is the target position (c). In this case, the slow speed means that the optical sensor 13 for the arm
When the speed changes from F (FIG. 4) to ON (FIG. 3), the speed can immediately stop at the position of the step.
0 pps, which is a speed close to an image moving one step at a time. When the carriage 4 moves and the pin 3 is fitted into the hole 5 of the carriage 4, the arm optical sensor 13 is turned from OFF (FIG. 4) to ON (FIG. 3) (d). When it is confirmed that has reached the target position (for example, the capping position), the carriage 4 is immediately stopped. Thus, the carriage 4
The relative position between the maintenance mechanism (capping mechanism, wiping mechanism, etc.) is accurately determined. With the carriage held at the target position, a maintenance operation such as a capping operation is performed.

The carriage 4 passes from the pre-position (X + 16), which is the position where the pin 3 never enters the hole 5 and is close to the position where the pin 3 enters, from the pre-position to the target position, and the pin 3 on the opposite side moves to If the arm optical sensor 13 does not turn on even if the optical sensor 13 does not enter the position 5 and moves to a position (X-16) close to the position where the pin 3 enters, it is processed as an error. That is, in this embodiment, the carriage 4 is connected to the stepping motor 8 by (16 × 2 + 1 =
If the sensor 13 does not turn on even if the number of steps (33 steps) is moved, it is processed as an error.

FIG. 6 is a flowchart showing the operation of the second embodiment of the carriage driving method in the ink jet recording apparatus to which the present invention is applied. In FIG. 6, by executing the same sequence as the carriage driving sequence described in the first embodiment (FIG. 5), the carriage 4
After the positioning of the maintenance mechanism (such as the capping mechanism arranged at the target position) is correctly performed,
When the operation of aligning the carriage 4 to the target position is further repeated, the following drive sequence (FIG. 6)
(The sequence shown in (A)) may be repeatedly executed. That is, when the positioning of the carriage 4 with respect to the maintenance mechanism (capping mechanism or the like disposed at the target position) is correctly performed, the arm optical sensor 13
Assuming that the carriage 4 has moved Z steps before is turned ON, the number of steps Y from the reference of the carriage 4 to the target position (the position where the carriage 4 has a correct relative positional relationship with the maintenance mechanism) is (Y = X + 16−Z ) Is required to be a step.

The reproducibility of turning on the optical sensor 13 for the arm may be determined by considering only the carriage operation accuracy of the sensor accuracy with respect to the Y step position. Has been found to be of the order. This number of steps (± 2 steps)
This value is always smaller than the required number of steps when simply accumulating component tolerances.

Therefore, after the positioning operation of the first embodiment (FIG. 5) is performed, when the operation of positioning the carriage 4 to the target position is started again, the “pin 3” as the preliminary position is used. Can be selected as the (Y + 3) step position. That is, after the carriage 4 is moved to the position of the (Y + 3) step to stop the carriage 4 at that position, the arm 12 on the recording apparatus main body side is moved from the position regulation state (FIG. 2) to the released state (FIG. 4). Move. When the arm 12 moves to the released state at this pre-position, the pin 3 of the arm 12 is pressed against the flat portion of the carriage 4 as shown in FIG. Next, from the position of the (Y + 3) step set as the pre-position, the target position Y
The carriage 4 is moved at a very low speed toward the position of the step.

When the carriage 4 is moved to the target position (the position of the Y step) and the optical sensor for arm 13 is turned on, the purpose of the carriage 4 is "the state where the pins 3 are inserted into the holes 5 of the carriage 4". The position has been reached, and the carriage 4 is immediately stopped. Thus,
The carriage 4 is positioned so as to be accurately positioned with respect to the maintenance mechanism. With the carriage 4 positioned at the target position, a maintenance operation such as a capping operation or a wiping operation is performed. Then, after the carriage drive described in the first embodiment (FIG. 5) is executed, the (Y +
3) The carriage driving sequence for setting the pre-position at the step position, that is, the sequence shown in FIG. 6A is repeatedly executed a required number of times.

In comparison with the case where the movement amount from the relative position (target position) in the carriage drive sequence according to the first embodiment described with reference to FIG. 5 is 1 to a maximum of 33 (= 16 + 1 + 16), the second amount described with reference to FIG. In the carriage drive sequence according to the embodiment, the movement amount from 1 to a maximum of 7 (= 3 + 1 + 3) until the relative position is obtained, and the same positioning accuracy as in the first embodiment can be ensured with a shorter sequence.

In the second embodiment shown in FIG.
If the optical sensor for arm 13 does not turn on even if it moves at a very low speed (3 × 2 + 1 = 7 steps) from the position of the (Y + 3) step to the position of the (Y-3) step, the carriage 4 is immediately moved. Stop and arm 12
By moving the pin 3 to the position regulating state shown in FIG. After the arm 12 is separated from the carriage 4, the carriage 4 is moved, and the carriage optical sensor 10 re-determines the reference position for the carriage operation. Then, the same positioning operation as that of the carriage driving sequence according to the first embodiment described with reference to FIG. 5 to set the pre-position to the position of (X + 16) steps is performed. If an error occurs in the carriage drive sequence, it is considered that an abnormal occurrence has occurred, so that the occurrence of the error is notified to the outside.

According to the embodiment described above, in the carriage driving method using the stepping motor 8 for driving the carriage 4 and the ink jet recording apparatus using the driving method, the carriage 4 is stopped at the target position (maintenance position). After stopping the carriage at a pre-position different from the target position, the pin 3 is pressed against the carriage from a direction substantially perpendicular to the carriage moving direction, and then the carriage 4 is moved from the pre-position to the direction of the target position. Since the carriage is stopped at the target position with the accuracy of the drive step of the stepping motor 8 by detecting the displacement of the pin 3 following the shape of the carriage 4 during movement, the size of the apparatus is increased. The recording means 7 mounted on the carriage 4 It is possible to improve the accuracy of the stop position of the carriage 4 at the time of performing maintenance of the wiping or the like, and it is possible to prevent the redundancy of operating time up to stopping the carriage.

In the target position, the pin 3 is engaged with a step or a hole 5 provided in the carriage 4, and the target position where the displacement of the pin is detected and the carriage is stopped is set to the stepping motor 8. When the carriage is stopped at the pre-position next time, the number of drive pulses to the target position after pressing the pin is reduced, or the pin 3 is pressed. When the number of driving pulses to the subsequent target position is reduced and the displacement of the pin is not detected even after exceeding the prescribed number of pulses for moving from the pre-position to the target position, the carriage is re-started. The position reference of No. 4 was obtained again, and the carriage was stopped at a pre-position farther from the target position than the previous time when the displacement of the pin 3 was not detected, and The carriage is moved after the carriage is pressed, so that the recording means 7 mounted on the carriage 4 can be more efficiently used for maintenance such as capping or wiping without increasing the size of the apparatus. 4 can improve the accuracy of the stop position, and can prevent redundant operation time until the carriage is stopped.

Further, the target position is a position for performing maintenance on the recording means such as capping or wiping of the recording means 7 or the pin 3
Is engaged with the hole 5 provided in the carriage 4 so as to serve also as a positioning means for preventing the carriage 4 from being displaced from a capping position covering the discharge port 82 of the recording means during non-recording, so that the efficiency is further improved. An ink jet recording apparatus capable of achieving the above effects is provided.

That is, according to the embodiment described above,
A hole shape 5 is provided on the carriage 4 side, and a movable arm 12 having a pin 3 that can be fitted into the hole 5 of the carriage 4 is provided on the recording apparatus main body side. The reference position of the operation of the carriage 4 is obtained by the optical sensor 10, and when the carriage 4 stops at the position where the capping or wiping is performed, the carriage 4 temporarily stops near the position to be stopped, and then the carriage 4 stops. The pin 3 is moved almost perpendicularly to the moving direction and pressed against the carriage 4. Thereafter, the carriage 4 moves at a very low speed toward the position to be stopped (target position) so that the carriage 4 can be stopped immediately after detecting the sensor.
The tip of the pin 3 enters the hole 5 provided in the carriage 4, and the displacement of the pin 3 is detected to immediately stop the carriage 4.

Further, in order to reduce the time required for the carriage 4 to move at a very low speed, the position at which the displacement of the pin 3 is detected when the carriage is stopped is stored. Adjust as follows. If the displacement of the pin 3 is not detected even when the number of pulses exceeds the specified number, the reference position of the carriage 4 is determined again by the optical sensor, and the pin 3 is moved from the position that is not detected to be farther from the previous position. A stop operation (carriage drive operation) similar to four-pressing is performed.
With the above-described means, it is possible to improve the accuracy of controlling the stop position of the carriage during capping and wiping, and prevent redundant operation time.

In the above embodiment, the case where the target position for aligning the carriage 4 is the capping position has been described as an example. However, the present invention relates to the case where the target position is another maintenance operation position such as the wiping position. And the same effect can be obtained. Also, in the above embodiment, the case where the pin 3 engages (fits) with the partner 5 is the hole 5 formed in the carriage 4, but the pin 3 engages instead of the hole 5. Possible steps may be provided.

In the above embodiment, the case where one recording head 7 is mounted on the carriage 4 has been exemplified. However, the present invention is directed to a case where a plurality of recording heads for recording with inks of different colors or the same color are used. The present invention can be similarly applied to a case where a plurality of recording heads that perform gradation recording at different densities and a plurality of recording heads in which these are combined are used, and the same effect can be achieved. Further, the present invention can be similarly applied to a case where maintenance mechanisms such as a capping mechanism and a wiping mechanism are arranged at a plurality of positions, and the same effects can be achieved. Further, the present invention provides a recording head having a configuration using a replaceable inkjet cartridge in which the recording head and the ink tank are integrated, a configuration in which the recording head and the ink tank are separated, and the space therebetween is connected by an ink supply tube or the like. The present invention can be similarly applied to any arrangement of the ink tank and the ink tank, and the same effect can be obtained. Note that, in the present invention, the ink jet recording apparatus
For example, the present invention can be applied to a case where a recording unit using an electromechanical transducer such as a piezo element is used, and the same effect can be obtained.

[0049]

As apparent from the above description, according to the first aspect of the present invention, in the carriage driving method using the stepping motor for driving the carriage, when the carriage is stopped at the target position, the target position is After the carriage is stopped at a different pre-position, a pin is pressed against the carriage from a direction substantially perpendicular to the carriage movement direction, and then the carriage is moved from the pre-position to the target position, following the shape of the carriage during this movement. Since the carriage is stopped at the target position with the accuracy of the driving step of the stepping motor by detecting the displacement of the pin, the recording means mounted on the carriage is capped without increasing the size of the apparatus. Or stop of the carriage during maintenance such as wiping It is possible to improve the accuracy of the location,
In addition, a carriage driving method is provided which can prevent redundant operation time required for stopping the carriage.

According to the second to fourth aspects of the present invention, in addition to the configuration of the first aspect, the pin is engaged with a step or a hole provided in the carriage at the target position.
The target position where the carriage is stopped by detecting the displacement of the pin is stored by the number of drive pulses of the stepping motor, and when the carriage is next stopped at the pre-position, the target position after pressing the pin is stored. A configuration for reducing the number of drive pulses to a position, or a specified pulse for moving from the pre-position to the target position when the number of drive pulses to the target position after pressing the pin is reduced. If the displacement of the pin is not detected even after exceeding the number, the position reference of the carriage is calculated again, and the carriage is stopped at a pre-position farther from the target position than the last time when the displacement of the pin was not detected, and the pin is stopped. The carriage is moved after pressing the carriage, so that a carriage driving method capable of achieving the above effect more efficiently is provided. It is.

According to the fifth aspect of the present invention, in an ink jet recording apparatus in which recording means is mounted on a carriage driven by a stepping motor and ink is discharged from the recording means to a recording material to perform recording, the carriage is moved to a target position. When stopping the carriage, the carriage is stopped at a pre-position different from the target position, and then a pin is pressed against the carriage from a direction substantially perpendicular to the carriage moving direction, and then the carriage is moved from the pre-position to the target position. Since the carriage is stopped at the target position with the accuracy of the driving step of the stepping motor by detecting the displacement of the pin that follows the shape of the carriage during this movement, the apparatus does not increase in size. The recording means mounted on the carriage is used for maintenance such as capping or wiping. It is possible to improve the accuracy of the stop position of the carriage when performing Nsu, and an ink jet recording apparatus is provided which can prevent redundant operating time up to stopping the carriage.

According to the invention of claims 6 to 10, in addition to the configuration of claim 5, the target position is a position for performing maintenance on the recording means such as capping or wiping of the recording means. A configuration in which the pin is engaged with a step or a hole provided in the carriage, a target position where the displacement of the pin is detected and the carriage is stopped is stored by the number of drive pulses of the stepping motor, and then the When stopping the carriage at the pre-position, a configuration in which the number of drive pulses to the target position after pressing the pin is reduced, and the number of drive pulses to the target position after pressing the pin is reduced. The displacement of the pin is not detected even when the number of pulses for moving from the pre-position to the target position is exceeded. The configuration for moving the carriage from pushing the pin stops the carriage farther advance position from the target position than again obtain the position reference again carriage, the displacement of the pin is not detected last time,
Alternatively, since the pin is engaged with a hole provided in the carriage to serve also as a positioning means for preventing the carriage from being displaced from a capping position covering the discharge port of the recording means during non-recording, the configuration is further improved. An ink jet recording apparatus capable of achieving the above effects is provided.

[Brief description of the drawings]

FIG. 1 is a schematic vertical cross-sectional view showing a configuration of a main part of an embodiment of an ink jet recording apparatus to which the present invention is applied.

FIG. 2 is a schematic elevation view showing a state where a carriage positioning mechanism mounted on the ink jet recording apparatus of FIG. 1 is in a position regulating state.

FIG. 3 is a schematic elevation view showing a state where a carriage positioning mechanism mounted on the ink jet recording apparatus of FIG. 1 is in a released state.

FIG. 4 is a schematic elevation view showing a state where a carriage mounted on the ink jet recording apparatus of FIG. 1 comes to a pre-position and a carriage positioning mechanism is in a released state.

FIG. 5 is a flowchart showing a first embodiment of an operation of aligning a carriage to a target position.

FIG. 6 is a flowchart showing a second embodiment of the operation of aligning the carriage to a target position.

FIG. 7 is a partial perspective view schematically illustrating a structure of an ink discharge unit of the recording unit in FIG.

FIG. 8 is a schematic longitudinal sectional view showing an example of a displacement preventing means of the capping mechanism.

FIG. 9 is a schematic longitudinal sectional view showing another example of the displacement preventing means of the capping mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cap 2 Cap holder 3 Pin 4 Carriage 5 hole 6 Spring 7 Recording means (Recording head) 8 Stepping motor 9 Belt 10 Optical sensor for carriage 11 Axis 12 Arm 13 Optical sensor for arm 14 Projection light shielding part 15 Rotating cam 16 Guide Shaft 81 Discharge port surface 82 Discharge port 85 Electrothermal converter

Claims (12)

[Claims] In a carriage driving method using a stepping motor for driving a carriage, when the carriage is stopped at a target position, the carriage is stopped at a pre-position different from the target position, and thereafter, is substantially perpendicular to the carriage movement direction. The pin is pressed against the carriage from the direction, and then the carriage is moved from the pre-position to the target position. The carriage is driven by the stepping motor by detecting the displacement of the pin following the shape of the carriage during this movement. A carriage driving method, wherein the carriage is stopped at the target position with step accuracy. 2. The method according to claim 1, wherein the pin is engaged with a step or a hole provided in the carriage at the target position. 3. A target position at which the carriage is stopped by detecting the displacement of the pin is stored according to the number of drive pulses of the stepping motor, and when the carriage is stopped at a pre-position, the pin is pressed. The method according to claim 1, wherein the number of drive pulses to the target position after the drive is reduced. 4. The method according to claim 1, wherein when the number of drive pulses to the target position after pressing the pin is reduced, even if the number of drive pulses for moving from the pre-position to the target position exceeds a predetermined number of pulses. If the displacement is not detected, the position reference of the carriage is obtained again, the carriage is stopped at a pre-position farther from the target position than the previous time when the displacement of the pin was not detected, and the carriage is moved after pressing the pin. The carriage driving method according to any one of claims 1 to 3, wherein the driving is performed. 5. An ink jet recording apparatus in which a recording means is mounted on a carriage driven by a stepping motor and ejects ink from the recording means to a recording material to perform recording, when the carriage is stopped at a target position. After the carriage is stopped at a pre-position different from the position, a pin is pressed against the carriage from a direction substantially perpendicular to the carriage moving direction, and then the carriage is moved from the pre-position to the target position. An ink jet recording apparatus that stops the carriage at the target position with the accuracy of the driving step of the stepping motor by detecting a displacement of a pin that follows the movement of the pin. 6. The ink jet recording apparatus according to claim 5, wherein the target position is a position where maintenance is performed on the recording unit such as capping or wiping of the recording unit. 7. The ink jet recording apparatus according to claim 5, wherein the pin is engaged with a step or a hole provided in the carriage at the target position. 8. A target position at which the carriage is stopped by detecting the displacement of the pin is stored according to the number of drive pulses of the stepping motor, and when the carriage is stopped at the pre-position, the pin is pressed. 8. The ink jet recording apparatus according to claim 5, wherein the number of drive pulses to the target position after the step is reduced. 9. When the number of drive pulses from the pre-position to the target position after the pin is pressed is reduced, even if the number of drive pulses from the pre-position to the target position exceeds the prescribed number of pulses. If the displacement is not detected, the position reference of the carriage is obtained again, the carriage is stopped at a pre-position farther from the target position than the previous time when the displacement of the pin was not detected, and the carriage is moved after pressing the pin. The inkjet recording apparatus according to any one of claims 5 to 8, wherein the inkjet recording is performed. 10. A positioning means for preventing the carriage from being displaced from a capping position covering a discharge port of a recording means during non-printing by engaging said pin with a hole provided in the carriage. The ink jet recording apparatus according to claim 5. 11. The ink jet recording means according to claim 5, wherein said recording means is an ink jet recording means provided with an electrothermal converter for generating thermal energy used for discharging ink. The inkjet recording apparatus according to any one of the preceding claims. 12. An ink jet recording apparatus according to claim 11, wherein said recording means discharges the ink from a discharge port using film boiling generated in the ink by thermal energy generated by the electrothermal transducer. .