JP2024001916A - Image recording apparatus - Google Patents

Abstract

To provide means for detecting a jam of a medium to be recorded generated downstream from a conveying roller in a conveying direction.SOLUTION: A printer 10 according to the present invention includes: a conveying part including a conveying roller 24 and conveying a sheet S in a conveying direction 6; a recording head 31 positioned downstream of the conveying direction 6 of the conveying roller 24 and recording an image on the sheet S being conveyed by the conveying part; a laser Doppler type optical sensor 40 positioned downstream of the conveying direction 6 of the conveying roller 24 and outputting a signal SS corresponding to the traveling state of the sheet S being conveyed by the conveying part; and a control unit 50. The control unit 50 detects a jam of the sheet S in the downstream of the conveying direction 6 from the conveying roller 24 based on the output signal SS of the optical sensor 40.SELECTED DRAWING: Figure 2

Description

The present invention relates to an image recording apparatus that transports a recording medium in a transport direction and records an image on the recording medium that is being transported.

Patent Document 1 describes a printer that starts feeding out recording paper by a pair of feeding rollers when a sensor that detects the position of a tension guide is turned on while the recording paper is being conveyed by a pair of paper feeding rollers. This printer determines that a paper feed failure has occurred in the paper feed roller pair if the sensor does not turn off even after the paper is fed by a predetermined amount after the paper feed roller pair starts conveying the recording paper.

Japanese Patent Application Publication No. 2011-143997

In the conventional printer described above, a jam may occur in which the leading edge of the recording paper that has passed through the pair of paper feed rollers slips under a unit (for example, a print head unit) in the printer. Even in this case, since the pair of conveying rollers continues to convey the recording paper, the tension of the recording paper is unlikely to fluctuate, and the position of the tension guide is also unlikely to fluctuate. Therefore, in the conventional printer described above, it is difficult to detect a jam that occurs downstream of the pair of paper feed rollers in the conveying direction.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide a means for detecting a jam of a recording medium that occurs downstream of the conveyance roller in the conveyance direction.

(1) The image recording apparatus of the present invention includes a transport section that transports the recording medium in the transport direction, and a transport section that transports the recording medium in the transport direction, and a transport section that is located downstream of the transport roller in the transport direction, and that is configured to transport the recording medium by the transport section. a recording head that records an image on a recording medium; and a laser Doppler optical sensor that is located downstream of the conveyance roller in the conveyance direction and outputs a signal according to the running state of the recording medium being conveyed by the conveyance section. and a control section. The control unit detects a jam of the recording medium downstream of the transport roller in the transport direction based on the output signal of the optical sensor.

According to the above-mentioned image recording device, the running state of the recording medium can be directly detected based on the output signal of the laser Doppler optical sensor, so jamming of the recording medium occurs downstream of the conveyance roller in the conveyance direction. Even if the jam is detected, the jam can be detected.

(2) Preferably, the image forming apparatus further includes a fixing device located downstream of the recording head in the transport direction, and the optical sensor may be located downstream of the fixing device in the transport direction.

(3) Preferably, the optical sensor may be located between the conveyance roller and the recording head in the conveyance direction.

(4) Preferably, the recording head records an image on a first surface of a recording medium being conveyed by the conveying section, and the optical sensor records an image on a second surface of the recording medium being conveyed by the conveying section. Alternatively, a laser beam may be irradiated onto the substrate, and the laser beam reflected by the second surface may be received.

(5) Preferably, the control unit acquires the running state of the recording medium being transported by the transport unit based on the output signal of the optical sensor, and controls the transport from the transport roller based on the acquired running state. A jam of the recording medium downstream in the direction may be detected.

According to the present invention, it is possible to detect a jam of a recording medium that occurs downstream of the conveyance roller in the conveyance direction.

FIG. 1 is an external perspective view of a printer 10 according to an embodiment of the invention. FIG. 2 is a schematic cross-sectional view taken along the line II-II in FIG. FIG. 3 is a block diagram of the printer 10. FIG. 4(A) is a diagram showing the arrangement position of the optical sensor 40 in the printer according to the modified example, and FIG. 4(B) is a diagram showing the arrangement position of the optical sensor 40 in the printer according to the modified example.

Embodiments of the present invention will be described below. Note that the embodiments described below are merely examples of the present invention, and it goes without saying that the embodiments of the present invention can be modified as appropriate without changing the gist of the present invention. In the following explanation, the progress from the starting point of the arrow to the ending point is expressed as the direction, and the movement on the line connecting the starting point and the ending point of the arrow is expressed as the direction. Further, a vertical direction 7 is defined based on the state in which the printer 10 is installed so that it can be used (the state shown in FIG. 1), and a front-back direction 8 is defined with the surface where the discharge port 13 of the printer 10 is formed as the front surface. 10 is viewed from the front, a left-right direction 9 is defined. The up-down direction 7, the front-back direction 8, and the left-right direction 9 are orthogonal to each other.

[Overview of printer 10]
The printer 10 according to the present embodiment is an example of an image recording device that conveys a sheet S (an example of a recording medium) in the conveyance direction and records an image on the sheet S being conveyed using an inkjet recording method. The printer 10 is a monochrome printer that ejects black ink onto the sheet S. Note that the printer 10 may be a color printer that ejects cyan, magenta, yellow, and black ink onto the sheet S. The sheet S is, for example, a roll of paper, a roll of sticker paper, a roll of film, or the like.

As shown in FIG. 1, the printer 10 includes a housing 11 having a generally rectangular parallelepiped shape. The housing 11 has a size that can be placed on a tabletop, for example. The printer 10 is used by being placed on a table, on the floor, or in a rack.

A discharge port 13, an operation panel 14, and a display section 15 are located on the front surface 12 of the housing 11. The discharge port 13 has a slit shape long in the left-right direction 9. A sheet S (see FIG. 2) on which an image has been recorded is discharged from the discharge port 13. The operation panel 14 is operated by the user of the printer 10. The user inputs various instructions, settings, etc. to the printer 10 by operating the operation panel 14 . The display unit 15 displays the status of the printer 10 and the like. The display unit 15 displays, for example, that an error such as a jam has occurred in the printer 10.

[Internal configuration of printer 10]
As shown in FIG. 2, the housing 11 includes a holder 21, a tensioner 22, a pair of transport rollers 23, a platen 26, supporting parts 27 and 28, a recording head 31, a heater 34, a CIS 35, an optical sensor 40, and a controller. section 50 is located. The conveying roller pair 23 includes a conveying roller 24 and a pinch roller 25. Optical sensor 40 includes a light emitting element 41 and a light receiving element 42. Furthermore, an ink tank (not shown) for storing ink is located within the housing 11. A cutter (not shown) for cutting the sheet S may be located near the discharge port 13 in the housing 11.

Inside the housing 11, the holder 21 extends in the left-right direction 9. A roll body R in which a long sheet S is wound around a core tube (not shown) is attached to the holder 21 . The holder 21 supports the roll body R so that the roll body R can rotate in the circumferential direction of the core tube. The holder 21 is rotated by a driving force transmitted from a transport motor (not shown). As the holder 21 rotates, the roll body R supported by the holder 21 also rotates.

The sheet S is pulled upward from the rear end of the roll body R and guided to the tensioner 22. A pair of transport rollers 23 is located in front of the tensioner 22 . The conveyance roller 24 is rotated by a driving force transmitted from a conveyance motor (not shown). Pinch roller 25 faces conveyance roller 24 . The transport roller pair 23 rotates while nipping the sheet S extending forward from the tensioner 22, thereby feeding the sheet S forward. The sheet S fed forward is supported by the platen 26 and the supporting parts 27 and 28 and is discharged from the discharge port 13. Note that when the cutter is located near the discharge port 13, the sheet S that has passed through the support portion 28 is cut into a desired length by the cutter and then discharged from the discharge port 13.

The conveyance direction of the sheet S is forward. The conveyance direction 6 of the sheet S is the front-back direction 8 . The holder 21 , the tensioner 22 , and the conveyance roller pair 23 are an example of a conveyance unit that includes the conveyance roller 24 and conveys the recording medium in the conveyance direction 6 . Note that the conveyance unit may include other elements that convey the sheet S. The upper surface of the sheet S being transported by the transport section is called a recording surface F1, and the lower surface is called a non-recording surface F2. The recording surface F1 is an example of the first surface. The non-recording surface F2 is an example of the second surface.

The recording head 31 is located downstream of the transport roller pair 23 in the transport direction 6 . The platen 26 is located below the recording head 31. The recording surface F1 of the sheet S faces the lower surface 32 of the recording head 31. The lower surface 32 of the recording head 31 has a plurality of nozzles 33 that open downward. Ink supplied from the ink tank is ejected downward from the plurality of nozzles 33 toward the recording surface F1 of the sheet S supported by the platen 26. As a result, an image is recorded on the recording surface F1 of the sheet S that is being transported by the transport unit.

The heater 34 is located downstream of the recording head 31 in the transport direction 6 . The support portion 27 is located below the heater 34. The heater 34 heats the sheet S supported by the support section 27. The heater 34 fixes the image recorded on the recording surface F1 of the sheet S in a short time. The heater 34 is an example of a fixing device.

A CIS (Contact Image Sensor) 35 is located downstream of the heater 34 in the transport direction 6 . The support portion 28 is located below the CIS 35. The CIS 35 reads the image recorded on the sheet S supported by the support section 28. The CIS 35 outputs the read image to the control unit 50.

[Control unit 50]
As shown in FIG. 3, the control unit 50 includes a CPU 51, a ROM 52, a RAM 53, an EEPROM 54, and an ASIC 55. The ROM 52 stores programs for the CPU 51 to execute various processes. The RAM 53 is used as a storage area for temporarily recording data, signals, etc. used when the CPU 51 executes a program, or as a work area for data processing. The EEPROM 54 stores information that should be retained even after the power is turned off.

The ASIC 55 receives signals from various parts within the printer 10 and controls the transport motor within the printer 10 according to control from the control section 50. The control unit 50 rotates the conveyance motor by driving the conveyance motor through the ASIC 55, thereby rotating the holder 21 and the conveyance roller 24 connected to the conveyance motor. Further, the control unit 50 causes ink to be ejected from the nozzles 33 of the print head 31 by outputting a drive signal to a drive element (not shown) of the print head 31 through the ASIC 55 . The ASIC 55 outputs a drive signal according to the amount of ink to be ejected from the nozzle 33. Further, the control unit 50 drives the heater 34 and the light emitting element 41 by outputting a control signal through the ASIC 55. The control unit 50 also receives output signals from the tensioner 22, CIS 35, and light receiving element 42 through the ASIC 55. Further, the operation panel 14 and the display section 15 are connected to the ASIC 55 .

[Jam detection using optical sensor 40]
As shown in FIG. 2, the optical sensor 40 is located between the heater 34 and the CIS 35 in the transport direction 6. That is, the optical sensor 40 is located downstream of the pair of transport rollers 23, the recording head 31, and the heater 34 in the transport direction 6, and upstream of the CIS 35 in the transport direction 6. The optical sensor 40 is located below the sheet S being transported by the transport section.

The optical sensor 40 is a laser Doppler type optical sensor including a light emitting element 41 and a light receiving element 42. The light emitting element 41 emits laser light L to the non-recording surface F2 of the sheet S being transported by the transport section. The laser beam L emitted from the light emitting element 41 is reflected by the non-recording surface F2 of the sheet S and enters the light receiving element 42. The light receiving element 42 outputs a signal SS corresponding to the intensity of the incident laser beam L to the control unit 50. Signal SS is the output signal of optical sensor 40. The traveling state of the sheet S can be detected by the laser Doppler optical sensor 40.

The control unit 50 acquires the running state of the sheet S being conveyed by the conveyance unit according to the output signal SS of the optical sensor 40. The control unit 50 detects a jam of the sheet S downstream of the conveyance roller 24 in the conveyance direction 6 based on the acquired running state.

For example, the control unit 50 acquires the presence or absence of conveyance of the sheet S (whether the sheet S is conveyed or not) and the conveyance speed of the sheet S based on the output signal SS of the laser Doppler type optical sensor 40. The control unit 50 controls the conveyance roller 24 in response to the fact that the conveyance of the sheet S cannot be detected based on the output signal SS of the optical sensor 40 even after a predetermined time has elapsed after instructing the conveyance unit to convey the sheet S. Therefore, it is determined that a jam of the sheet S has occurred downstream in the conveyance direction 6. Alternatively, when the conveyance speed of the sheet S is smaller than a predetermined threshold after a predetermined time has elapsed after instructing the conveyance unit to convey the sheet S, the control unit 50 causes the conveyance roller 24 to move the sheet S in the conveyance direction 6. It is determined that a jam of the sheet S has occurred downstream.

When the control unit 50 determines that a jam of the sheet S has occurred, it stops image recording and notifies the user of the occurrence of a jam. For example, when the control unit 50 determines that a jam of the sheet S has occurred, the control unit 50 causes the conveyance unit to convey the sheet S, the recording head 31 to record an image, the heater 34 to heat the sheet S, and the CIS 35 to image the sheet S. Stop reading. Further, the control unit 50 displays an error message indicating the occurrence of a jam on the display unit 15. The user of the printer 10 looks at the error message displayed on the display unit 15 and performs a process to clear the jam of the sheet S (such as a process to remove the jammed sheet S).

[Effect]
As shown above, the printer 10 according to the present embodiment includes a conveyance section that includes the conveyance roller 24 and conveys the sheet S in the conveyance direction 6, and a conveyance section that is located downstream of the conveyance roller 24 in the conveyance direction 6. a recording head 31 that records an image on the sheet S being conveyed by the conveyance unit; and a laser Doppler that is located downstream of the conveyance roller 24 in the conveyance direction 6 and outputs a signal SS according to the running state of the sheet S being conveyed by the conveyance unit. The optical sensor 40 includes a type optical sensor 40 and a control section 50. The control unit 50 detects a jam of the sheet S downstream of the conveyance roller 24 in the conveyance direction 6 based on the output signal SS of the optical sensor 40 .

According to the printer 10 described above, the running state of the sheet S can be directly detected based on the output signal SS of the laser Doppler type optical sensor 40, so that the sheet S can be prevented from jamming downstream of the transport roller 24 in the transport direction 6. Even if a jam occurs, the jam can be detected.

The printer 10 further includes a heater 34 located downstream of the recording head 31 in the transport direction 6, and the optical sensor 40 is located downstream of the heater 34 in the transport direction 6. Therefore, when the heater 34 is provided downstream of the recording head 31 in the conveyance direction 6, by providing the laser Doppler type optical sensor 40 downstream of the recording head 31 and the heater 34 in the conveyance direction 6, the heater 34 can be The running state of the sheet S downstream in the transport direction can be detected, and a jam of the sheet S occurring downstream of the transport roller 24 in the transport direction 6 can be detected.

Further, the recording head 31 records an image on the recording surface F1 of the sheet S being conveyed by the conveying section, and the optical sensor 40 irradiates the non-recording surface F2 of the sheet S being conveyed by the conveying section with laser light L. , receives the laser beam L reflected by the non-recording surface F2. Therefore, the running state of the sheet S can be detected based on the output signal SS of the laser Doppler optical sensor 40 provided on the side of the sheet S where no image is recorded.

Further, the control unit 50 acquires the running state of the sheet S being transported by the transport unit based on the output signal SS of the optical sensor 40, and based on the acquired running state, the control unit 50 determines whether the sheet S is located downstream of the transport roller 24 in the transport direction 6. Detect S jam. Thereby, it is possible to detect a jam of the sheet S occurring downstream of the conveyance roller 24 in the conveyance direction 6.

[Modified example]
Regarding the printer 10 according to the above embodiment, various modifications can be made. In the above embodiment, the optical sensor 40 is located downstream of the transport roller pair 23, the recording head 31, and the heater 34 in the transport direction 6, and upstream of the CIS 35 in the transport direction 6. is not limited to this.

For example, the optical sensor 40 may be located downstream of the transport roller pair 23, the recording head 31, the heater 34, and the CIS 35 in the transport direction 6, as shown in FIG. 4(A). Alternatively, the optical sensor 40 may be located downstream of the pair of transport rollers 23 and upstream of the recording head 31, heater 34, and CIS 35 in the transport direction 6, as shown in FIG. 4(B). In the latter printer, the optical sensor 40 is located between the conveyance roller 24 and the recording head 31 in the conveyance direction 6. Therefore, the running state of the sheet S between the conveyance roller 24 and the recording head 31 can be detected, and a jam of the sheet S occurring downstream of the conveyance roller 24 in the conveyance direction 6 can be detected.

In the above embodiment, the method by which the recording head 31 records an image on the sheet S is a line head type inkjet recording method, but is not limited to this, and may also be a serial type inkjet recording method, for example. good. The printer according to this modification includes a carriage on which a recording head 31 is mounted, and records an image on a sheet S by ejecting ink from nozzles 33 of the recording head 31 while the carriage moves in the left-right direction 9. .

Although the printer 10 according to the above embodiment is equipped with the heater 34 and the CIS 35 downstream of the recording head 31 in the conveyance direction 6, the printer according to the modification example does not include at least one of the heater 34 and the CIS 35. Good too.

6...Conveyance direction 10...Printer (image recording device)
21...Holder (conveyance section)
22...Tensioner (conveyance section)
23... Conveyance roller pair (conveyance section)
24... Conveyance roller 31... Recording head 34... Heater (fixer)
40... Optical sensor 41... Light emitting element 42... Light receiving element 50... Control unit

Claims (5)

a conveyance unit that includes a conveyance roller and conveys the recording medium in the conveyance direction;
a recording head that is located downstream of the conveyance roller in the conveyance direction and records an image on a recording medium being conveyed by the conveyance section;
a laser Doppler optical sensor that is located downstream of the conveyance roller in the conveyance direction and outputs a signal according to the running state of the recording medium being conveyed by the conveyance section;
It is equipped with a control section,
The control section is an image recording apparatus that detects a jam of the recording medium downstream of the conveyance roller in the conveyance direction based on an output signal of the optical sensor. further comprising a fixing device located downstream of the recording head in the transport direction,
The image recording apparatus according to claim 1, wherein the optical sensor is located downstream of the fixing device in the transport direction. The image recording apparatus according to claim 1, wherein the optical sensor is located between the conveyance roller and the recording head in the conveyance direction. The recording head records an image on a first surface of the recording medium being conveyed by the conveyance section,
The image according to any one of claims 1 to 3, wherein the optical sensor irradiates a second surface of the recording medium being conveyed by the conveyance section with a laser beam and receives the laser beam reflected by the second surface. Recording device. The control unit acquires the running state of the recording medium being transported by the transport unit based on the output signal of the optical sensor, and based on the acquired running state, the control unit acquires the running state of the recording medium downstream of the transport roller in the transport direction. The image recording apparatus according to claim 1, wherein the image recording apparatus detects a jam of a medium.

Images