JP3437566B2 - Serial printer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a serial printer such as an ink jet printer which forms an image on the surface of a sheet by reciprocating a head in the main scanning direction with respect to a sheet conveyed in the sub-scanning direction.

[0002]

2. Description of the Related Art In a serial printer including an ink jet printer, a head is reciprocated in a main scanning direction with respect to a sheet conveyed in a sub scanning direction to form an image on the surface of the sheet. For example, in an inkjet printer, ink is ejected from a plurality of nozzles arranged on the head onto the surface of the paper, and the ink ejected from the nozzles is used to form an image normally on the surface of the paper. The proper distance between the tip and the surface of the paper is predetermined.

That is, if the distance between the head and the surface of the paper is too narrow, the surface of the paper comes into contact with the head, causing wear and damage to the head. On the other hand, if the distance between the head and the surface of the paper is too wide, a so-called satellite phenomenon occurs and the image forming state deteriorates. The satellite phenomenon is a phenomenon in which fine ink particles ejected subsequently from the main body particles of ejected ink from the nozzles of the head adhere to the landing points on the surface of the paper, which are separated from the landing points of the main body particles. That is, as shown in FIG. 13A, when the distance between the head 101 and the paper 102 is proper, the minute ink particles 111 to 113 are located within the landing points of the ink main body particles 110 on the surface of the paper 102. Attached,
The image on the surface of the paper 102 is not contaminated.
On the other hand, as shown in FIG.
When the distance between the sheet and the paper 102 is wide, the minute ink particles 1
11 to 113 adhere to the surface of the paper 102 other than the landing points of the ink main body particles 110 and stain the image on the surface of the paper 102.

Therefore, in the conventional serial printer, the position of the head can be moved in the direction (height direction) perpendicular to the surface of the paper, and the position of the head in the height direction can be changed according to the thickness of the paper on which the image is formed. By adjusting
The separation distance (height) between the surface of the paper and the head is kept constant regardless of the thickness of the paper. Normally, such a height adjustment of the head is performed by a user by operating an operation member such as a height adjustment lever arranged on a side surface of the apparatus.

Further, in the serial printer, the image forming range in the main scanning direction in which the head should be reciprocated also changes according to the size of the paper on which the image is formed. Therefore, in order to shorten the time required for image formation and improve the operation efficiency, the head is reciprocated only within the range of the main scanning direction of the paper to be image-formed, and the head moves outside the image formation range. It is necessary to save unnecessary time for movement, and for this purpose, it is necessary to provide means for detecting the length of the set sheet in the main scanning direction.

However, if the structure only for detecting the length of the paper in the main scanning direction is provided, the size of the apparatus is increased and the cost is increased. For this reason, a relatively inexpensive small-sized serial printer does not have a configuration for detecting the length of the paper in the main scanning direction, and the maximum size of the image formation target regardless of the width of the set paper. The head is reciprocated over the entire range of the size in the main scanning direction.

[0007]

However, there is no conventional serial printer capable of detecting the setting contents of the image forming conditions such as the position of the head in the height direction and the paper size with a simple structure. There is a problem that it is not possible to judge whether the forming conditions are properly set and the image forming state is deteriorated and the apparatus is worn or damaged.

For example, even if the height of the head adjusted by the user does not match the thickness of the paper on which the image is formed, the image forming process is executed, and the head is worn or damaged, and the image quality is deteriorated. Occurs. In addition, regardless of the width of the paper on which the image is to be formed, when the head is reciprocally moved over the entire range of the maximum size paper in the main scanning direction when the image is formed, the head is scanned even in the range where the paper to be opposed does not exist. Therefore, there is a problem that the image forming time becomes long and the operation efficiency is lowered, and the apparatus is contaminated due to the feeding of a sheet that does not fit the image data size.

An object of the present invention is to use a timing fence (also referred to as a code strip) used for stabilizing the scanning speed of a head and a reading sensor for reading the same to determine image forming conditions such as head height and paper size. It is an object of the present invention to provide a serial printer capable of detecting the setting contents, and accurately detecting the setting contents of the image forming conditions without increasing the size of the apparatus, increasing the cost, and lowering the operating efficiency.

[0010]

According to a first aspect of the present invention, there is provided a timing fence arranged along the main scanning direction, and a reading sensor mounted on a carriage reciprocating within the image forming range in the main scanning direction. In a serial printer that includes, and controls the movement state of the carriage based on the reading data of the timing fence by the reading sensor during image formation, the carriage stop position outside the image forming range is changed according to the setting content of the image forming conditions. A stop position changing member is provided, another reading area is formed outside the reading area read by the reading sensor at the time of image formation on the timing fence, and the carriage is moved to one end side at a timing other than at the time of image formation. Image sensor based on the reading data of another reading area of the timing fence Characterized in that it has a control unit for executing a detection process for detecting the setting of the condition.

According to the first aspect of the invention, the existing timing fence and the reading sensor are used in the serial printer, and the reading data of the timing fence by the reading sensor when the carriage is moved to one of the end sides. The setting contents of the image forming conditions are detected based on the above. Therefore, whether the setting content of the image forming condition is appropriate or not, or the image forming according to the set image forming condition is performed without increasing the size of the apparatus or increasing the cost.

The invention described in claim 2 is characterized in that the image forming condition is a size of a sheet on which an image is to be formed.

According to the second aspect of the present invention, the existing timing fence and the reading sensor are used in the serial printer, and the reading data of the timing fence by the reading sensor when the carriage is moved to one of the end sides. Based on the above, the setting content of the size of the paper on which the image is to be formed is detected. Therefore, determination of suitability of the setting content of the size of the paper on which the image is to be formed, or image formation according to the setting content of the size of the paper on which the image is to be formed does not increase the size of the apparatus or increase the cost. Done.

According to a third aspect of the present invention, the control section executes the image forming process only when the detected setting content of the image forming condition and the preset content of the image forming condition match. Characterize.

According to the third aspect of the present invention, the setting contents of the image forming conditions detected based on the read data of the timing fence by the read sensor when the carriage is moved to one of the end portions are external. The image forming process is executed only when the image data is input from the device or the like and the contents instructed in advance match. Therefore, if the setting contents of the image forming conditions do not match the instruction contents, the image forming process is not performed, and the improper image forming process that causes the deterioration of the image forming state and the stain or damage of the apparatus is surely performed. Prohibited by.

According to a fourth aspect of the present invention, the stop position changing member sets the carriage stop position outside the image forming range on the side where the carriage stops before setting a sheet on which an image is to be formed as an image forming condition. The feature is that it is changed according to the content.

According to the fourth aspect of the invention, the setting content of the image forming condition is detected based on the read data of the reading sensor which changes depending on the stop position of the carriage before setting the paper on which the image is to be formed. Therefore,
The setting contents of the image forming condition are detected by the movement of the carriage before the image forming process, and the operation efficiency does not decrease due to the detecting process of the setting contents of the image forming condition.
Further, since the setting contents of the image forming conditions are detected from the stop position when the carriage is moved before setting the paper, even if the setting contents are improper, there is no problem such as damage of the apparatus. .

According to the invention described in claim 5, the stop position of the carriage outside the image forming range on the side where the carriage is located before the setting of the paper on which the image is to be formed is set from the surface of the paper of the ink cartridge mounted on the carriage. A first stop position changing member that changes according to the setting content of the height, and an image of the stop position of the carriage outside the image forming range on the side opposite to the side where the carriage is located before setting the paper on which the image is to be formed. A second stop position changing member for changing the size of the sheet to be formed is provided, and two different reading areas are provided on both sides of the timing fence outside the reading area read by the reading sensor during image formation. And the control unit causes the carriage to move the end portion on the side where the first stop position changing member is provided before setting the paper on which the image is to be formed. The moved, characterized in that moving the end portion on the side of the carriage after a set of sheets to be formed image is a second stop position changing member is provided.

According to the fifth aspect of the invention, the setting contents of the height of the ink cartridge from the surface of the paper are detected based on the stop position when the carriage is moved before setting the paper, and after the paper is set. The setting content of the paper size is detected based on the stop position when the carriage is moved. Therefore, the setting contents of the height of the ink cartridge from the surface of the paper and the setting contents of the paper size are detected by the reciprocating movement of the carriage performed before the start of the image forming process, and the efficiency of the image forming process is reduced. The setting contents of the plurality of image forming conditions are detected without performing the operation. Also, because the setting contents of the height of the ink cartridge from the surface of the paper are detected based on the stop position when the carriage is moved before setting the paper, even if the setting contents are incorrect, the head part of the ink cartridge Does not contact the paper, and the head is not worn or damaged. Further, since the setting content of the paper size is detected based on the stop position when the carriage is moved after setting the paper, the size of the paper actually set is detected.

According to a sixth aspect of the present invention, the control section makes the driving force of the carriage when moving to the end portion weaker than the driving force of the carriage when forming an image.

According to the sixth aspect of the invention, when the image forming condition is detected, the carriage is driven with a driving force weaker than that during image formation. Therefore, the impact generated when the movement of the carriage is forcibly restricted by the stop position changing member is mitigated, and the occurrence of device failure or damage is prevented.

[0022]

1 is an external view of a serial printer according to an embodiment of the present invention, and FIG. 2 is a side view showing a schematic configuration of the serial printer. On the front side of the serial printer body 51, a paper feed tray 52 and a paper discharge tray 5 are provided.
3 are mounted vertically with the paper feed tray 52 facing down. A guide plate 54 is provided on the upper surface of the paper feed tray 53 so as to be movable over a predetermined range in a direction orthogonal to the paper feed direction. The guide plate 54 comes into contact with the side end surfaces of the plurality of sheets of paper placed on the upper surface of the paper feed tray 52, and aligns the placement state of the plurality of sheets of paper on the upper surface of the paper feed tray 52.

Inside the serial printer main body 51, there are provided a feeding roller 55, a paper feeding roller 56, a conveyance guide 57, a registration roller 58, a paper discharging roller 59, a platen 60, an ink cartridge 3 and holding shafts 6a and 6b. There is. The feeding roller 55 feeds the papers P placed on the paper feed tray 52 one by one toward the paper feed roller 56 by rotation. The paper feed roller 56 is configured to feed the fed paper P.
Are guided into the conveyance path 57. The registration roller 58 guides the paper P between the platen 60 and the ink cartridge 3 in synchronization with the operation of the ink cartridge 3 in the main scanning direction. The paper discharge roller 59 discharges the paper P on which the image formation is completed to the paper discharge tray 53.

The holding shafts 6a and 6b guide the movement of the ink cartridge 3 in the main scanning direction. The ink cartridge 3 ejects ink from the head portion at the lower end onto the surface of the paper P in accordance with image data while moving forward once in the main scanning direction. During this period, the conveyance of the sheet by the registration rollers 58 in the sub-scanning direction is temporarily stopped.
The registration roller 58 conveys the paper P in the sub-scanning direction by a distance corresponding to the number of nozzles arranged in the sub-scanning direction in the head portion while the ink cartridge 3 is returning. In this way, an image is formed on the entire surface of the paper P by repeating the conveyance of the paper P by the predetermined distance in the sub-scanning direction by the registration rollers 58 while the ink cartridge 3 reciprocates in the main scanning direction.

FIG. 3 is a perspective view showing the structure of the main part of the serial printer. Inside the serial printer main body 51, the ink cartridge 3 is mounted on the carriage 1 together with the ink tank 2. Carriage 1
Is a holding shaft 6a arranged parallel to the main scanning direction,
Guided by 6b, it reciprocates in the main scanning direction. On the back side of the carriage 1, a slide shaft 4 is arranged on the upper side, and a timing fence 5 is arranged below the slide shaft 4. Timing fence 5
Faces the reading sensor 8 provided on the back side of the carriage 1.

FIG. 4 is an external view showing the structure of the carriage provided in the serial printer. Carriage 1
Has a hollow shape, and the ink cartridge 3 and the ink tank 2 are mounted inside in this order from the upper surface side. A bearing 1 a is formed at the lower end of the carriage 1 on the back side. The holding shaft 6a on the back side is fitted into the bearing 1a. At the front end of the bottom surface of the carriage 1, a recess 1b is formed.
Are formed. The holding shaft 6a on the front side comes into contact with the recess 1b from below. Further, a protrusion 1c projects from a lower end portion of one side surface of the carriage 1 on the front surface side.

The carriage 1 moves to the right end side of the movement range in the main scanning direction and stops when the serial printer is powered on and when the image forming work is started. When the start of the image forming work is instructed, the carriage 1
Moves to the left end side of the moving range, and then reciprocates within the image forming range in the main scanning direction according to the width of the sheet on which the image is to be formed.

FIG. 5 is a front view showing a timing fence provided in the serial printer. Inside the serial printer main body 51, the timing fence 5
Faces the back surface of the carriage 1 over the entire movement range of the carriage 1 in the main scanning direction. On the reading surface of the timing fence 5 facing the reading sensor 8 of the carriage 1, the print area 5a is located in the center, the height detection area 5b is located near the right end, and the paper width detection area 5c is located near the left end.
Has been assigned. In each of the print area 5a, the height detection area 5b, and the paper width detection area 5c, white portions and black portions are repeatedly formed at regular intervals in the main scanning direction.

The print area 5a is used for constant-speed movement control of the carriage 1 during image formation, similar to the timing fence provided in the conventional serial printer. That is, the length of the print area 5a in the main scanning direction is
The length of the carriage 1 in a stopped state is set to have an acceleration region necessary for reaching a predetermined speed at the time of image formation on both sides of a range having the same length as the width of the maximum size of the image formation target. There is. The reading sensor 8 provided on the carriage 1 reads an image in the print area 5a on the timing fence 5 while the carriage 1 is moving during image formation. The moving speed of the carriage 1 is controlled so that the white portion image and the black portion image in the image read by the reading sensor 8 have a change cycle that matches a predetermined cycle.

Height detection area 5b and paper width detection area 5c
Is used to detect the height of the ink cartridge 3 and the length of the paper in the main scanning direction by the configuration and processing described later.

FIG. 6 is a side view showing the structure of the operation lever provided in the serial printer. The operation lever 7 is arranged on one side surface of the serial printer main body 51. The operating lever 7 is formed by projecting an operating portion 7b, a stopper 7c, a locking piece 7d and a gear portion 7e from a part of the peripheral surface of a disk-shaped base 7a. Operating lever 7
7A is a position inside the serial printer 51 shown in FIG. 7A around the hole 7f at the center of the base body 7a, and FIG.
It is rotatably supported between the position shown in FIG.

The operation unit 7b is a serial printer main body 51.
Is exposed to the outside from the upper surface of. The stopper 7c is selectively exposed at a position where it abuts the protrusion 1c of the carriage 1 by the rotation of the operation lever 7. The elastic member 9 is locked to the locking piece 7d. The elastic member 9 selectively stops the operation lever 7 at either the position shown in FIG. 7 (A) or the position shown in FIG. 7 (B). The operation lever 7 is shown in FIG.
Stopper 7c when stopped at the position shown in (A)
Is not exposed at the position of contact with the protrusion 1c of the carriage 1, and the stopper 7c is exposed at the position of contact with the protrusion 1c of the carriage 1 when the operating lever 7 is stopped at the position shown in FIG. 7B. . The gear portion 7e meshes with an adjusting gear 4a fixed to one end of the rotary shaft of the slide shaft 4.

FIG. 8 is a front view showing the structure of the slide shaft provided in the serial printer. The slide shaft 4 has a columnar shape, and contacts the upper portion of the rear side of the carriage 1 inside the serial printer main body 51 in the entire movement range of the carriage 1 in the main scanning direction. The slide shaft 4 is fixed with its central axis eccentric with respect to a rotary shaft 4b having one end fixed with an adjust gear 4a. As described above, the adjusting gear 4a meshes with the gear portion 7f formed on the operation lever 7. Therefore, the rotation of the operation lever 7 causes the slide shaft 4 to rotate eccentrically with respect to the rotation shaft 4b, and the amount of protrusion of the peripheral surface of the slide shaft 4 toward the front surface side, that is, the carriage 1 side changes.

When the operating lever 7 is stopped at the position shown in FIG. 7A, the amount of protrusion of the slide shaft 4 toward the front side is small, and the rear surface of the carriage 1 is pressed by the peripheral surface of the slide shaft 4. The front side of the carriage 1 is stopped at the lower position. On the other hand, in the state where the operation lever 7 is stopped at the position shown in FIG.
The amount of protrusion of the slide shaft 4 to the front side increases,
The back surface of the carriage 1 is pressed by the peripheral surface of the slide shaft 5, the carriage 1 rotates about the holding shaft 6a, and the front surface side of the carriage 1 stops at the upper position. At this time, the head portion of the lower end of the ink cartridge 3 mounted on the carriage 1 is positioned about 0.2 to 0.7 mm higher than the state shown in FIG. 7 (A).

Therefore, by selectively rotating the operation lever 7 to the position shown in FIG. 7A or the position shown in FIG. 7B, the head portion of the ink cartridge 3 mounted on the carriage 1 is normally moved. It is possible to reciprocate in the main scanning direction while being positioned at either the lower position corresponding to the paper or the upper position corresponding to the thick paper. Also,
When the head portion of the ink cartridge 3 mounted on the carriage 1 is located at the lower position corresponding to the plain paper, the stopper 7c of the operation lever 7 serves as the protrusion 1c of the carriage 1.
Position where the stopper 7c of the operation lever 7 contacts the protrusion 1c of the carriage 1 without being exposed to the position where the stopper 7c of the ink cartridge 3 mounted on the carriage 1 is positioned at the upper position corresponding to thick paper. Exposed to.

FIG. 9 is a block diagram showing the structure of the control unit of the serial printer. The control unit of the serial printer is a CPU 21 including a ROM 22 and a RAM 23.
The reading sensor 8, the interface 24, the image memory 2
5, input / output devices such as a motor driver 26, a head driver 27, and an operation panel controller 28 are connected to each other. The CPU 21 centrally controls the input / output device according to a program previously written in the ROM 22. At this time, the data input / output to / from the CPU 21 is RA
It is stored in a predetermined memory area of M23.

The reading sensor 8 inputs the reading data of the timing fence 5 to the CPU 21. Interface 2
Reference numeral 4 accepts data input from a host device 29 such as a personal computer. The image memory 25 stores the image data input via the interface 24. The motor driver 26 drives the motor 30 based on the drive data output from the CPU 21. The rotation of the motor 30 is transmitted to the carriage 1 as a moving force in the main scanning direction via a transmission mechanism (not shown). The head driver 27 drives the head portion of the ink cartridge 3 based on the drive data output from the CPU 21. The operation panel controller 28 inputs the operation data of the key switch 31a provided on the operation panel 31 to the CPU 21, and displays the display data output from the CPU 21 on the display 31b.

FIG. 10 is a flow chart showing a processing procedure at the time of the ink cartridge height detection processing in the control section of the serial printer. The CPU 21, which constitutes the control unit of the serial printer according to the present invention, detects the movement amount of the carriage 1 in the right end direction based on the read data of the height detection area 5b of the timing fence 5 read by the read sensor 8, and this detection is performed. Carriage 1 based on the results
It is determined whether or not the projection 1c of the ink cartridge 3 is in contact with the stopper 7c formed on the operation lever 7, and based on this determination result, the head portion of the ink cartridge 3 mounted on the carriage 1 is operated by operating the operation lever 7. Whether the lower position corresponding to plain paper or the upper position corresponding to thick paper is set is detected. The CPU 21 compares this detection result with the paper thickness data input from the host device 29, and operates the operation lever 7 to operate the ink cartridge 3
It is determined whether or not the height setting of the head section is correct.

That is, the CPU 21 receives image data including paper thickness data from the host device 29 (s1),
The motor 30 is driven to move the carriage 1 to the predetermined position in the right end direction (s2). At this time, the CPU 21
Indicates whether the projection 1c of the carriage 1 is in contact with the stopper 7c of the operation lever 7 or not, that is, the ink depending on whether or not the read data of the read sensor 8 changes while the motor 30 is being driven. It is detected whether the lower position corresponding to the plain paper or the upper position corresponding to the thick paper is set as the position of the head portion of the cartridge 3 (s3 to s5). The CPU 21 compares the detection result with the paper thickness data input from the host device 29 (s6),
If they do not match, a message instructing the switching of the operating lever is displayed on the display 31b of the operation panel 31 (s6 → s7), and the motor 30 is reversed by a predetermined amount to return to s2 (s8 → s2). When the detection result coincides with the paper thickness data in s6, the CPU 21 outputs the head drive data corresponding to the image data input from the host device 29 to the head driver 27 to execute the image forming process ( s9).

By the above processing, the existing timing fence 5 and the reading sensor 8 in the serial printer are used to detect the movement state of the carriage 1, and the carriage 1
The setting state of the position of the head portion of the ink cartridge 3 mounted in is detected, and the image forming process is executed only when the detection result matches the paper thickness data designated by the host device 29. The paper thickness data input to the CPU 21 of the serial printer from the host device 29 is input to the host device 29 by the operator who sets the paper on the serial printer, and the paper thickness data input from the host device 29 is It usually matches the thickness of the paper loaded in the serial printer's input tray. Therefore, by the above processing, the head portion of the ink cartridge 3 can be reliably positioned at a position corresponding to the thickness of the paper fed from the paper feed tray as the target of the image forming processing.

Further, in a serial printer, normally, when the power is turned on or before the image forming process is started, the carriage 1
To the right end. At the same time, the operation lever 7 is provided on the right side of the serial printer body in consideration of operability. Therefore, in the above-described embodiment, the height detection region 5b is arranged on the right end side of the timing fence 5, and the ink cartridge 3 is arranged on the right end side of the device in which the carriage 1 is located at the time of power-on or before the start of the image forming process. The height of the head portion of the carriage 1 is detected, and the size of the detection member and the unnecessary movement of the carriage 1 are eliminated. That is, the height of the head portion of the ink cartridge 3 can be simultaneously detected by the operation of moving the carriage 1 to the right end side when the power is turned on or before the image forming process is started.

Further, even when the head portion of the ink cartridge 3 is set to the lower position corresponding to the plain paper when the thick paper is set after the carriage 1 is moved to the right end side, the carriage 1 is moved to the left end. The head position can be detected to be improperly set before moving to the side, and the carriage 1 is moved to the left end side after the thick paper is set to detect the head position. The parts do not come into contact with each other, and the wear and damage of the head part can be prevented in advance.

In addition, by forming a plurality of stoppers that are exposed at a plurality of positions in the main scanning direction according to the amount of rotation of the operating lever 7, the height of the head portion of the ink cartridge 3 is increased over three steps. Even if it changes, the position of the head portion of the ink cartridge 3 can be accurately detected.

FIG. 11 is a diagram showing a configuration relating to detection of the length of the sheet in the main scanning direction in the serial printer according to the embodiment of the present invention. A switching lever 10 is rotatably arranged on the left end side of the carriage 1 in the main scanning direction. The switching lever 10 has a shape obtained by cutting a cylinder with a surface inclined at a predetermined angle with respect to the axial direction.
0a is a contact piece 1d protruding from the left side surface of the carriage 1.
Abut. The rotation shaft of the switching lever 10 is arranged parallel to the main scanning direction, which is the moving direction of the carriage 1, and the contact piece 1d of the carriage 1 is placed on the inclined surface 10a at a position that does not coincide with the rotation shaft of the switching lever 10. Contact.

A gear portion 10b is formed at the left end of the switching lever 10. The operation of the guide plate 54 movably arranged on the paper feed tray 52 is transmitted to the gear portion 10b via a transmission mechanism (not shown). That is, FIG.
As shown in, the guide plate 54 is movable on the upper surface of the paper feed tray 52 over a predetermined range in the main scanning direction, and the paper feed direction of the paper placed on the upper surface of the paper feed tray 52 is shown. It comes into contact with the side surface parallel to (the direction orthogonal to the main scanning direction). Therefore, the guide plate 54 moves in the main scanning direction on the upper surface of the paper feed tray 52 according to the length of the paper to be fed in the main scanning direction.

The movement of the guide plate 54 is converted into a rotational movement by, for example, a rack gear fixed to the guide plate 54 and an intermediate gear meshing with the rack gear, and the intermediate gear is directly or via another gear. By engaging with the gear portion 10b of the switching gear 10, the switching lever 10 rotates as the guide plate 54 moves. When the switching lever 10 rotates, the contact position between the inclined surface 10a of the switching lever 10 and the contact piece 1d of the carriage 1 in the rotation axis direction of the switching lever 10 (main scanning direction) is displaced, and the carriage 1 moves toward the left end direction. The movement range of changes.

FIG. 12 is a flow chart showing a processing procedure at the time of detecting the length of the sheet in the main scanning direction in the control section of the ink jet printer. The CPU 21, which constitutes the control unit of the serial printer according to the present invention, detects the amount of movement of the carriage 1 in the left end direction based on the read data of the paper width detection area 5c of the timing fence 5 read by the read sensor 8, and this detection is performed. Based on the result, the length of the sheet set in the sheet feed tray 52 in the main scanning direction is determined. The CPU 21 compares this determination result with the size of the image data input from the host device 29, and determines whether or not the paper suitable for the size of the image data is set in the paper feed tray 52. Further, the CPU 21 determines the reciprocating range of the carriage 1 in the main scanning direction at the time of image formation based on the determination result of the length of the paper set in the paper feed tray 52 in the main scanning direction.

That is, when image data is input from the host device 29 (s11), the CPU 21 drives the motor 30 to move the carriage 1 toward the left end (s1).
2). At this time, the CPU 21 counts the number of appearances of the white image in the read data of the read sensor 8 while the motor 30 is being driven (s13), and based on this count value, the carriage 1
The contact position between the contact piece 1d and the inclined surface 10a of the switching lever 10 is determined (s14), and the size of the sheet set in the paper feed tray 52 is detected based on the determination result (s14).
15).

The CPU 21 compares this detection result with the size of the image data input from the host device 29 in the main scanning direction (s16). If they do not match, the image data size is displayed on the display 31b of the operation panel 31. A message to the effect that paper suitable for the above should be set in the paper feed tray 52 is displayed (s16 → s17), the motor 30 is reversed by a predetermined amount and the process returns to s12 (s18 → s12). When the detection result matches the image data size in s16, the CPU 21 outputs the head drive data corresponding to the image data input from the host device 29 to the head driver 27 to execute the image forming process ( s19).

Through the above processing, the existing paper tray 5 is used to detect the moving state of the carriage 1 by using the existing timing fence 5 and reading sensor 8 in the serial printer.
The size of the paper set to 2 is detected, and the image forming process is executed only when the detection result matches the image data input from the host device 29. As a result, a paper having a size smaller than the image data size is set in the paper feed tray 52, and ink based on the image data is ejected from the ink cartridge mounted on the carriage 1 to a portion where the paper does not exist, and the device and the paper. It is possible to prevent the stains from occurring.

The image data input from the host device 29 to the CPU 21 of the serial printer is stored in the host device 2 by an operator who sets paper on the serial printer.
It was created in 9 and is usually the host device 2
The image data size input from 9 matches the paper size set in the paper feed tray 52. Therefore, s1
The reciprocating movement range of the carriage 1 in the main scanning direction at the time of image forming processing may be set according to the sheet size detected in step 5 (s16 → s21, s2).
2).

Further, since the contact position between the inclined surface 10a of the switching lever 10 and the contact piece 1d of the carriage 1 continuously changes according to the rotation amount of the switching lever 10, the object of image formation in the serial printer is determined. Even when there are a large number of paper sizes, the respective paper sizes can be accurately detected.

Considering that the carriage 1 is moved to the right end before starting the image forming process, and further moved to the left end to start the image forming process, the carriage 1 is moved to the right side. When the carriage 1 is moved to the end portion, the ink cartridge height detection process shown in FIG. 10 is executed. After that, when the carriage 1 is moved to the left end portion, the length of the paper in the main scanning direction shown in FIG. It is efficient to execute the height detection process.

Further, when the carriage 1 is moved in the height detection process of the ink cartridge shown in FIG. 10 and the length detection process of the paper in the main scanning direction shown in FIG.
By supplying the motor 30 with driving power lower than the driving power during the image forming process, the impact when the protrusion 1c of the carriage 1 and the contact piece 1d contact the stopper 7c and the inclined surface 10a of the switching lever 10 is weakened. The device may be prevented from being broken or damaged.

Further, in the timing fence 5,
By forming an area of a color identifiable by the reading sensor 8 between the print area 5a and each of the height detection area 5b and the paper width detection area 5c, during the height detection processing of the ink cartridge and the paper. It is possible to accurately recognize that the reading sensor 8 faces each of the height detection area 5b and the paper width detection area 5c during the detection processing of the length in the main scanning direction of the sheet, and the operation lever 7 and the guide plate 54 are operated. There is no false detection of status.

In addition, in the processing of s8 in FIG. 10 and the processing of s17 in FIG. 12, warning data may be output to the host device that has output the image data.

The height of the ink cartridge, and
The present invention can be implemented in the same manner when detecting the setting content of the image forming conditions other than the length of the sheet in the main scanning direction.

[0058]

According to the invention described in claim 1, the existing timing fence and the reading sensor are used in the serial printer, and the timing fence is provided by the reading sensor when the carriage is moved to one of the end portions. By detecting the setting content of the image forming condition based on the read data of, it is possible to determine whether the setting content of the image forming condition is appropriate, or to perform image formation according to the set image forming condition.
This can be performed without increasing the size of the device and increasing the cost.

According to the second aspect of the present invention, the existing timing fence and the reading sensor are used in the serial printer, and the reading of the timing fence by the reading sensor when the carriage is moved to one of the end sides. By detecting the setting content of the size of the paper on which the image is to be formed based on the data, it is possible to judge whether the setting content of the size of the paper on which the image is to be formed is appropriate or to set the size of the paper on which the image is to be formed. It is possible to form an image according to the contents without increasing the size of the apparatus or increasing the cost.

According to the third aspect of the present invention, the setting contents of the image forming conditions detected based on the reading data of the timing fence by the reading sensor when the carriage is moved to one of the end sides are: When the image data is input from an external device and the like, the image forming process is executed only when the specified contents match, so that the image forming process is not performed when the set contents of the image forming conditions do not match the specified contents. In this way, it is possible to prevent deterioration of the image forming state and stain or damage of the apparatus.

According to the invention described in claim 4, the setting contents of the image forming conditions are detected based on the read data of the reading sensor which changes depending on the stop position of the carriage before setting the paper on which the image is to be formed. The setting contents of the image forming condition can be detected by the movement of the carriage before the image forming process, and the detection process of the setting contents of the image forming condition does not cause a decrease in operating efficiency. By detecting the setting content of the image forming condition from the stop position when the is moved, even if the setting content is improper, trouble such as damage of the apparatus does not occur.

According to the invention described in claim 5, the setting contents of the height of the ink cartridge from the surface of the paper are detected based on the stop position when the carriage is moved before setting the paper, and the paper is set. By detecting the setting contents of the paper size based on the stop position when the carriage is moved later, the height of the ink cartridge from the surface of the paper can be increased by the reciprocating movement of the carriage performed before the start of the image forming process. Setting contents and paper size setting contents can be detected, the setting contents of a plurality of image forming conditions can be detected without lowering the image forming processing efficiency, and before the paper is set. The setting contents of the height of the ink cartridge from the surface of the paper are detected based on the stop position when the carriage is moved. Without the head portion of the ink cartridge even if positive a contacts the paper, does not cause wear or damage to the head portion. Further, since the setting content of the paper size is detected based on the stop position when the carriage is moved after setting the paper, it is possible to accurately determine whether or not the size of the paper actually set is proper. You can

According to the sixth aspect of the present invention, when the image forming condition is detected, the carriage is driven with a driving force weaker than that during image formation, so that the movement of the carriage is forcibly restricted by the stop position changing member. It is possible to mitigate the shock that occurs when the device is operated and prevent the occurrence of device failure or damage.

[Brief description of drawings]

FIG. 1 is an external view of a serial printer according to an embodiment of the present invention.

FIG. 2 is a side view showing a schematic configuration of the serial printer.

FIG. 3 is a perspective view showing a configuration of a main part of the serial printer.

FIG. 4 is an external view showing a configuration of a carriage provided in the serial printer.

FIG. 5 is a front view showing a timing fence provided in the serial printer.

FIG. 6 is a side view showing a configuration of an operation lever provided in the serial printer.

FIG. 7 is a diagram illustrating a movement state of an ink cartridge mounted on a carriage by operating the operation lever.

FIG. 8 is a front view showing a configuration of a slide shaft provided in the serial printer.

FIG. 9 is a block diagram showing a configuration of a control unit of the serial printer.

FIG. 10 is a flowchart showing a processing procedure at the time of the ink cartridge height detection processing in the control unit of the serial printer.

FIG. 11 is a diagram showing a configuration related to detection of the length of a sheet in the main scanning direction in the serial printer according to the embodiment of the present invention.

FIG. 12 is a flowchart showing a processing procedure at the time of detection processing of the length of a sheet in the main scanning direction in the control unit of the inkjet printer.

FIG. 13 is a diagram illustrating a state where a satellite phenomenon occurs due to an improper gap between a head portion of an ink cartridge and a paper surface in a general inkjet printer.

[Explanation of symbols]

1-carriage 1c-protrusion 1d-abutting piece 3-ink cartridge 4-slide shaft 5-Timing fence 7-Operating lever 7c-Stopper (stop position change member) 8-reading sensor 10-Switching lever (stop position changing member)

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoji Kimura 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Corporation (72) Inventor Norihiro Ochi 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Sharp shares In-company (72) Inventor Shunichi Hayashiyama 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation (56) Reference JP-A-2-107472 (JP, A) JP-A-49-108908 (JP, A) ) JP-A-2-305674 (JP, A) JP-A-10-226120 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 19/18 B41J 2/01

Claims (6)

(57) [Claims] 1. A timing fence comprising a timing fence arranged along the main scanning direction and a reading sensor mounted on a carriage that reciprocates within the image forming range in the main scanning direction. In a serial printer that controls the movement state of the carriage based on the read data of, the stop position changing member that changes the stop position of the carriage outside the image forming range according to the setting contents of the image forming conditions is provided, and the timing fence forms the image. Sometimes, another reading area is formed outside the reading area that the reading sensor reads, and when the carriage is moved to one of the end sides at a timing other than when the image is being formed, another reading area of the timing fence is read by the reading sensor. Executes a detection process that detects the settings of image forming conditions based on the read data. A serial printer characterized by having a control unit. 2. The serial printer according to claim 1, wherein the image forming condition is a size of a sheet on which an image is to be formed. 3. The image forming process according to claim 1, wherein the control unit executes the image forming process only when the detected image forming condition setting contents match the previously instructed image forming condition contents. The listed serial printer. 4. The stop position changing member changes the stop position of the carriage outside the image forming range on the side where the carriage stops before setting the paper on which the image is to be formed, according to the setting contents of the image forming conditions. Item 4. A serial printer according to any one of items 1 to 3. 5. The stop position of the carriage outside the image forming range on the side where the carriage is located before setting the paper on which the image is to be formed depends on the setting content of the height of the ink cartridge mounted on the carriage from the surface of the paper. And a first stop position changing member that changes the stop position of the carriage outside the image forming range on the side opposite to the side where the carriage is located before setting the paper on which the image is to be formed, and the size of the paper on which the image is to be formed. A second stop position changing member that changes according to the setting contents of the timing fence is provided, and two kinds of different reading areas are formed on both sides of the timing fence outside the reading area read by the reading sensor at the time of image formation. But,
Before setting the paper on which the image is to be formed, the carriage is moved to the end on the side where the first stop position changing member is provided, and after setting the paper on which the image is to be formed, the carriage is moved to the second stop position changing member. The serial printer according to claim 1, wherein the serial printer is moved to an end on the side where the is provided. 6. The serial printer according to claim 1, wherein the control unit makes the driving force of the carriage when moving to the end portion weaker than the driving force of the carriage when forming an image.