Recording device

Abstract

To provide a recording device which can detect the shape of a sheet with excellent efficiency even if a housing has the relatively narrow width.SOLUTION: A recording device according to the present invention comprises: conveyance means which conveys a sheet; a carriage which moves in the first direction heading toward a second end from a first end of the sheet conveyed by the conveyance means and the second direction opposite to the first direction; a first sensor which is arranged in the carriage and detects the sheet; and a second sensor which is arranged in the carriage so as to be apart in the first direction from the first sensor and detects the sheet. The recording device executes any of a first detection operation of making the carriage move in a first distance and making the first sensor detect a space between the side of the second end and the side of the first end of the sheet, and a second detection operation of making the carriage move in the second distance longer than the first distance and making the first sensor and the second sensor detect the space between the side of the second end and the side of the first end of the sheet.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a recording apparatus that records on a sheet supplied from a roll around which the sheet is wound.

Background Art

[0002] In a recording apparatus that records on a roll around which a sheet is wound, the leading end portion of the sheet may have an inappropriate shape for recording. In the recording apparatus of Patent Document 1, it is possible to detect the shape of the leading end portion of the sheet using one sensor mounted on the carriage before the recording operation. And when the detected shape of the leading end portion of the sheet is inappropriate for recording, the leading end portion of the sheet is cut with a cutter.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, when the width of the housing is small with respect to the movement range of the carriage, one sensor cannot detect the shape of the sheet. On the other hand, by using two sensors, the shape of the sheet can be detected. It has been found that when using two sensors regardless of the width of the sheet, the detection efficiency may deteriorate. Therefore, an object of the present invention is to provide a recording apparatus that can efficiently detect the shape of a sheet even in a housing that is relatively narrow with respect to the movement range of the carriage.

Means for Solving the Problems

[0005] The recording device of the present invention comprises: a transport means for transporting a sheet including a first sheet and a second sheet narrower than the first sheet; a recording means for recording an image on the sheet transported by the transport means; and a carriage that moves in a second direction opposite to a first direction toward the second end of the sheet transported by the transport means, wherein the recording device comprises: a first sensor disposed on the carriage for detecting the sheet; a second sensor disposed on the carriage away from the first sensor in the first direction for detecting the sheet; a switching means for switching so that only one of the first sensor and the second sensor is connected to a port; and a control means for performing a detection operation in which the first end side of the first sheet is detected by a signal from the first sensor connected to the port, and the second end side of the first sheet is detected by a signal from the second sensor connected to the port. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a recording device that can efficiently detect the shape of a sheet even if the housing is relatively narrow in width relative to the movement range of the carriage. [Brief explanation of the drawing]

[0007] [Figure 1] This is a diagram showing the system configuration of the recording device. [Figure 2] This is a schematic cross-sectional view of the recording device. [Figure 3] This is a top view of the recording unit, including the carriage. [Figure 4] This diagram shows the relationship between the carriage width and the seat width. [Figure 5] This diagram shows the relationship between the width of the sheet and the position of the sensor. [Figure 6] This is a flowchart showing the pre-cutting process. [Figure 7] This is a flowchart illustrating the detection process using a single sensor. [Figure 8] This is a flowchart illustrating the detection process using two sensors. [Figure 9]This is a diagram comparing processing times. [Figure 10] This diagram shows the carriage's movement range and the seat's position in the case of center-based feeding. [Modes for carrying out the invention]

[0008] Embodiments will be described below with reference to the drawings. While multiple features are described, not all of these features are necessarily essential to the invention, and the features may be combined in any way. Furthermore, in the drawings, identical or similar configurations are given the same reference numeral, and redundant descriptions may be omitted.

[0009] In the embodiments, "recording" includes not only the formation of meaningful information such as characters and figures, but also the formation of images, patterns, etc., on a sheet, or the processing of a medium. In the embodiments, paper is assumed as the sheet, but cloth, plastic film, etc., may also be used. Furthermore, the present invention is applicable to electrophotographic recording devices other than inkjet systems.

[0010] (Embodiment 1) <Recording device> In this embodiment, the recording device is shown as having only a recording function, but it is not limited to this. For example, the recording device may also be a multifunction device (MFP: Multi-Function Peripheral) that includes a reading unit for reading images on a document and functions as a copier, or has other functions added.

[0011] The recording device of this embodiment will be described with reference to the drawings. Figure 1 is a diagram showing the system configuration of the recording device. In Figure 1, the recording device 100 can be connected to the host computer 190 via the network 191. The recording device 100 has an input / output I / F 122, a ROM I / F 125, a memory controller 126, a host I / F 127, a CPU (Central Processing Unit) 128, and an image processing unit 130. These are connected via the system bus 132. Furthermore, the recording device 100 has a Flash ROM 123 and a RAM 124, which are connected to the system bus 132 via the ROM I / F 125 and the memory controller 126, respectively.

[0012] The CPU 128 is a control unit in the form of a microprocessor (microcomputer), which controls the operation of the recording device 100 by executing programs and starting hardware. The Flash ROM 123 stores programs for execution by the CPU 128 and various data necessary for the various operations of the recording device 100. The RAM 124 is used as a work area for the CPU 128, as a temporary storage area for various received data, and for storing various setting data.

[0013] The image processing unit 130 performs various image processing tasks, such as converting the recording data handled by the recording device 100 into image data, and other image processing. The image processing unit 130 also converts the color space of the image data contained in the input recording data (e.g., YCbCr) to the standard RGB color space (e.g., sRGB). Furthermore, the image processing unit 130 applies various image processing tasks to the image data as needed, such as syntactic analysis, resolution conversion to a number of pixels that can be recorded, image analysis, and image correction. The image data obtained through image processing is stored in the RAM 124.

[0014] The recording device 100 includes a recording head 151, various motors, and various sensors. The motors include a cutter motor 162, a conveyance motor 163, a maintenance motor 164, a carriage motor 165, and a feeding motor 166. The sensors include a sensor group 171 such as an encoder, and sensors 301A and 301B for detecting a sheet. Each component is connected to the system bus 132 via a head I / F 152, a motor driver 161, or a sensor I / F 172. However, only one of the signals from the sensors 301A and 301B is connected to the sensor I / F by switching. That is, the signal is switched so that only one is input to the common input port. Note that there may be a configuration with two input ports corresponding to the sensors 301A and 301B.

[0015] The recording head 151 is controlled by the CPU 128 via the head I / F 152, and records an image on a sheet based on image data. The recording head 151 discharges ink in synchronization with the conveyance of the sheet and the movement of the carriage, and records an image on the sheet.

[0016] The cutter motor 162 is a motor for driving a cutter that cuts a sheet fed from a roll, and is controlled by the CPU 128 via the motor driver 161. By driving the cutter motor 162, the leading end of the sheet can be cut into a desired shape, and the sheet after recording an image can be cut to a predetermined length.

[0017] The conveyance motor 163 is a motor for driving the conveyance roller 204 that conveys the sheet, and is controlled by the CPU 128 via the motor driver 161. During the maintenance operation of the recording head 151, the operation of the maintenance unit 207 is switched by driving the conveyance motor 163. The maintenance motor 164 is a motor used during the maintenance operation of the recording head 151, and is controlled by the CPU 128 via the motor driver 161. The carriage motor 165 is a motor for driving the carriage of the recording head 151, and is controlled by the CPU 128 via the motor driver 161. The feeding motor 166 is a motor for rotating the roll and conveying the sheet in cooperation with the conveyance motor 163, and is controlled by the CPU 128 via the motor driver 161. By driving the feeding motor 166 to rotate the roll in the reverse direction, the sheet on the conveyance roller can also be wound onto the roll side. From the sensor group 171 such as an encoder and a sheet detection sensor, the CPU 128 acquires sensor signals via the sensor I / F 172, thereby detecting the conveyance state of the roll, the position of the carriage 203, and the like.

[0018] The input / output unit 121 includes hard keys, a panel for the user to perform various operations such as recording settings, and a display unit for displaying (notifying) various information to the user. Here, the recording settings include the setting of the validity / invalidity of precut described later. The input / output unit 121 is controlled by the CPU 128 via the input / output unit I / F 122. Note that the input / output unit 121 may display information to the user by outputting sound (buzzer, voice, etc.) based on the acoustic information from the sound generator. However, although the input / output unit 121 is provided in the recording apparatus 100, it is not limited thereto, and for example, it may be connected as an external configuration via the network 191. Also, the host computer 190 may serve as the input / output unit 121. Furthermore, in addition to the input / output unit 121, the recording apparatus 100 may be further connected to other input / output units via the network 191 or the like.

[0019] The host computer 190 is, for example, an external device that serves as a source of recording data, and may have a printer driver installed. The recording device 100 may be connected to a data supply device that serves as a source of recording data, such as an image reader, digital camera, or smartphone, instead of the host computer 190. The host I / F 127 receives recording data from the host computer 190 via stream communication, and the supplied recording data is stored in the RAM 124 via the memory controller 126. The connection between each device and the recording device 100 is not limited to wired connections, but may also be wireless.

[0020] Figure 2 is a schematic cross-sectional view of the recording device 100. Figure 2(a) shows the sheet feeding operation from the roll, and Figure 2(b) shows the sheet discharge operation after it has been cut from the roll. The roll around which the sheet is wound is installed on the rear side of the recording device 100. Images are recorded on the sheet fed from the roll in the recording unit, and the sheet with the recorded image is discharged from the discharge port 205 on the front side of the recording device 100. An input / output unit 121 for operating the recording device 100 is provided above the discharge port 205.

[0021] The feeding operation, which involves feeding the sheet 202 from the roll 201, is performed by rotating the roll 201 with the drive of the feeding motor 166. The fed sheet 202 is transported along the transport path by the rotation of the transport roller 204 with the drive of the transport motor 163, and reaches a position opposite the carriage 203 equipped with the recording head 151. The recording head 151 records an image by ejecting ink onto the transported sheet 202. A cutter unit 206 is positioned downstream of the recording head 203 in the sheet transport direction. The discharge operation, which involves discharging the sheet cut from the roll, is performed by moving the cutter unit 206 in a direction intersecting the transport direction relative to the sheet with the drive of the cutter motor 162. The cut sheet is discharged from the discharge port 205, and the user can receive the sheet on which the image has been recorded. The recording device 100 may also be configured to have transport paths corresponding to the roll and the cut sheet, and to enable the transport and discharge of both the roll and the cut sheet.

[0022] Figure 3 is a top view of the recording unit including the carriage. The recording unit includes a recording head 151, a carriage 203 that moves the recording head 151, and a platen 302 that supports the transported sheet. Here, in the direction of movement of the carriage 203, the side on which the maintenance unit 207 is installed is called the home side, and the opposite side is called the away side. The carriage 203 can move in a forward direction from the home side to the away side, and in the reverse direction.

[0023] The carriage 203, equipped with a recording head 151, reciprocates along the guide 208 in a direction intersecting the sheet transport direction. The carriage 203 is driven by a carriage motor 163. The recording device 100 is positioned opposite the carriage 203 equipped with the recording head 151, and has a maintenance unit 207 on the outside of the sheet 202 transport path. The recording head 151 can be maintained by the maintenance unit 207. The recording operation is performed by a transport operation to transport the sheet and an ejection operation to eject ink onto the sheet. The transport operation is performed by rotating the transport roller 204 driven by the transport motor 163 to transport the sheet 202. The ejection operation is performed by reciprocating the recording head 151 in the direction of transport while ejecting ink from it. By performing the transport operation and the ejection operation alternately, an image is recorded on the sheet 202.

[0024] The carriage 203 has two sensors 301A and 301B positioned apart in the direction of movement. Each sensor consists of an LED, which is a light-emitting element, and a photodiode, which is a light-receiving element. The LED emits light toward the sheet 202 or platen 302, and the photodiode receives light from the sheet 202 or platen 302. The sensor outputs a detection signal of a voltage level corresponding to the amount of light received by the photodiode. If the voltage level is below a predetermined threshold, it is determined that the sheet 202 has been detected, and if the voltage level exceeds the threshold, it is determined that the platen has been detected. As a result, the presence or absence of the sheet 202 can be detected by the sensor. When the sensor moves between one end and the other end of the sheet, the position of the sheet and the position of the platen can be determined, and thus the shape of the sheet can be detected.

[0025] Figure 4 shows the relationship between the carriage width and the sheet width. The width of the carriage 203 in the direction of movement is WC, and the width of the sheet 202 is WP. The home-side position of the carriage 203 when it is at the limit of movement toward the home side within the carriage 203's range of movement is defined as "0". The away side is defined as the positive direction, and the distance from the "0" position is defined as the position of the carriage in the direction of movement. During recording, the carriage 203 moves back and forth within the range of movement between the limit position PH on the home side and the limit position PA on the away side. The range of movement of the carriage 203 is smaller than the sum of the maximum sheet width WP and the carriage 203 width WC. This relationship allows for a smaller width for the recording device 100's housing. In the recording device 100, the home-side end PL of the sheet 202 is transported along the reference position BL on the home side of the transport path, regardless of the width of the sheet 202.

[0026] Figure 5 shows the relationship between the width of the sheet 202 and the position of the sensors. Figure 5(a) shows the case where the width of the sheet 202 is wide, and Figure 5(b) shows the case where the width of the sheet 202 is narrow. The movable range of the carriage 203 is from PH to PA, which is PH-PA. The detection range of the home-side sensor 301A is WSA, and the detection range of the away-side sensor 301B is WSB. When the width of the sheet 202 is wide, the away-side edge PR of the sheet 202 is outside the detection range WSA of the home-side sensor 301A. In this case, the away-side sensor 301B is moved to the away-side edge PR of the sheet 202, and the edge PR is detected by sensor 301B. When the width of the sheet 202 is narrow, the away-side edge PR of the sheet 202 is within the detection range WSA of the home-side sensor 301A. In this case, the home-side sensor 301A is moved to the away-side end of the sheet 202, and the side end PR is detected by the sensor 301A.

[0027] <Detection Action> Figure 6 shows a flowchart of the pre-cutting operation, which involves cutting the leading edge of the sheet. The pre-cutting operation is performed during the preparation phase before the recording operation.

[0028] In process S101, the CPU 128 performs edge detection on both sides of the sheet 202 in the width direction. Since the width of the sheet is unknown during edge detection, two sensors, sensor 301A and sensor 301B, are used by switching between them. First, the sheet 202 is transported in a first quantity downstream in the transport direction. Next, the carriage 203 is moved so that the center of the home-side sensor 301A is 50 mm away from the reference position BL, which is the feeding reference, to the sheet position. The sheet position is the position where the sheet exists, regardless of the sheet width. The CPU 128 moves the carriage 203 in the opposite direction, towards the home side, from the sheet position. When sensor 301A detects the home-side edge PL of the sheet 202, the carriage 203 is stopped. After that, the CPU 128 moves the carriage 203 in the forward direction, towards the away side. When the away-side sensor 301B detects the away-side edge PR of the sheet 202, the carriage 203 is stopped. The width of sheet 202 is calculated based on the distance between the position of the home side edge PL and the position of the away side edge RR of the detected sheet 202.

[0029] In step S102, the CPU 128 determines whether to perform pre-detection with one of the sensors 301A or with both sensors 301A and 301B. Specifically, it compares the value obtained by adding the width WP of the sheet 202 to the reference position BL (BL+WP) with the value obtained by subtracting the width WC of the carriage 203 from the limit position PA where the carriage 203 can move toward the away side (PA-WC). If the position of the away end of the sheet (BL+WP) does not exceed the reachable position of the home side sensor 301A (PA-WC), the CPU 128 determines that pre-detection is possible with only the home side sensor 301A. This determination confirms that the home side sensor 301A can move beyond the away side end PR of the sheet 202. Since the only variable is the width WP of the sheet 202, either detection operation 1 or detection operation 2 will be executed based on the width WP. If it is determined that pre-detection can be performed with one sensor, the process proceeds to step S103; if pre-detection is to be performed with two sensors, the process proceeds to step S104.

[0030] In step S103, the CPU 128 executes detection operation 1, which performs pre-detection using one sensor. The details are explained in the flowchart in Figure 7.

[0031] In step S104, the CPU 128 performs detection operation 2, which involves pre-detection using two sensors. Details are explained in the flowchart in Figure 8.

[0032] In step S105, the CPU 128 determines whether a pre-cut operation is necessary. If the platen 302 is detected in step S103 or S104, the leading edge of the sheet 202 has an inappropriate shape. If the CPU 128 determines that a pre-cut operation is necessary, it proceeds to step S106. If the platen 302 is not detected, the CPU 128 determines that a pre-cut operation is unnecessary and terminates the pre-cut operation flowchart.

[0033] In step S106, the CPU 128 transports the sheet 202 downstream in the transport direction by an amount corresponding to the cutting length, and cuts the leading edge of the sheet 202 to the appropriate shape. After that, the pre-cut operation flowchart ends.

[0034] Here, detection operation 1 in process S103 will be explained using the flowchart in Figure 7. Detection operation 1 is the case when the width of sheet 202 is narrow as shown in Figure 5(b). In this case, pre-detection is performed only by the home-side sensor 301A located on carriage 203.

[0035] In process S201, the CPU 128 moves the carriage 203 to the detection start position. The carriage 203 is moved so that the center of the sensor 301A is 3 mm inward from the away side edge PR of the sheet 202 towards the home side, which is the inside of the sheet, so that it can be detected by the sensor 301A. Note that the sheet 202 is being transported in a second quantity, which is smaller than the first quantity.

[0036] In process S202, the CPU 128 starts moving the carriage 203 toward the home side. As a result, the sensor 301A moves in the opposite direction from its inner position on the away side.

[0037] In step S203, the CPU 128 determines whether the sensor 301A detected the platen 302 while the carriage 203 was moving. If the platen 302 is detected, the leading edge of the sheet 202 has an inappropriate shape. If the platen 302 is detected, the process proceeds to step S204; otherwise, the process proceeds to step S206.

[0038] In process S204, the CPU 128 stops the movement of the carriage 203.

[0039] In step S205, the CPU 128 transports the sheet 202 until the sensor 301A detects the sheet 202. This allows the cutting length in step S106 to be determined. After the sheet 202 is detected, the process returns to step S202 and resumes the movement of the carriage 203 toward the home side from the stopped position.

[0040] In step S206, the CPU 128 checks whether the sensor 301A has moved to the end position. The end position is 3 mm inward from the home side edge PL of the sheet 202 towards the away side of the sheet 202. If the sensor 301A has not reached the end position, the process returns to step S203. If the sensor 301A has moved to the end position, detection operation 1 is terminated.

[0041] Next, detection operation 2 in process S104 will be explained using the flowchart in Figure 8. Detection operation 2 is the case when the width of sheet 202 is wide as shown in Figure 5(a). Pre-detection is performed using two sensors, sensor 301A and sensor 301B.

[0042] In process S301, the CPU 128 moves the carriage 203 to the detection start position. The carriage 203 is moved so that the center of the sensor 301B is located 3 mm inward from the away side edge PR of the sheet 202 toward the home side, so that it can be detected by the away side sensor 301B. Note that the sheet is being transported in a second quantity, which is less than the first quantity.

[0043] In step S302, the CPU 128 begins moving the carriage 203 toward the home side. As a result, the sensor 301B moves in the opposite direction from its inner position on the away side.

[0044] In step S303, the CPU 128 determines whether the sensor 301B detected the platen 302 while the carriage 203 was moving. If the platen 302 is detected, the leading edge of the sheet 202 has an inappropriate shape. If the platen 302 is detected, the process proceeds to step S304; otherwise, the process proceeds to step S306.

[0045] In process S304, the CPU 128 stops the movement of the carriage 203.

[0046] In step S305, the CPU 128 transports the sheet 202 until the sensor 301B detects the sheet 202. This allows the cutting length in step S106 to be determined. After the sheet 202 is detected, the process returns to step S302 and resumes the movement of the carriage 203 toward the home side from the stopped position.

[0047] In step S306, the CPU 128 checks whether the sensor 301B has moved to the switching position. The switching position is 55 mm from the away side edge PR of the sheet 202 toward the home side. If the sensor 301B has not reached the switching position, the process returns to step S303. If the sensor 301B has moved to the switching position, the process proceeds to step S307.

[0048] In process S307, the CPU 128 moves the carriage 203 so that the center of sensor 301A is positioned 50 mm from the away side edge PR of sheet 202 toward the home side, so that it can be detected by sensor 301A on the home side. Sensor 301A moves toward the away side beyond the range detected by sensor 301B by 5 mm. This is because it is necessary to switch between sensor 301A and sensor 301B since there is only one input port. In this way, the entire width of the sheet can be detected by sensors 301A and 301B.

[0049] In step S308, the CPU 128 starts moving the carriage 203 toward the home side. This causes the sensor 301A to move in the opposite direction from the switching position.

[0050] In step S309, the CPU 128 determines whether the sensor 301A detected the platen 302 while the carriage 203 was moving. If the platen 302 is detected, the leading edge of the sheet 202 has an inappropriate shape. If the platen 302 is detected, the process proceeds to step S310.

[0051] In process S310, the CPU 128 stops the movement of the carriage 203.

[0052] In step S311, the CPU 128 transports the sheet 202 until the sensor 301A detects the sheet 202. This allows the cutting length in step S106 to be determined. After the sheet 202 is detected, the process returns to step S308 and resumes the movement of the carriage 203. If the platen 302 is not detected, the process proceeds to step S312.

[0053] In step S312, the CPU 128 determines whether the sensor 301A has completed moving to the end position. The end position is 3 mm inward from the home side edge PL of the sheet 202 towards the away side. If the sensor 301A has not reached the end position, the process returns to step S309. If the sensor 301A has reached the end position, the detection operation 2 is terminated. Note that the switching order and movement direction of the sensors 301A and 301B may be any combination other than the one described above, as long as it is in line with the spirit of this invention.

[0054] Here, we will explain the processing time for detection operation 1 and detection operation 2 using Figure 9. The vertical axis represents the position of carriage 203 (arrow direction is away side), and the horizontal axis represents time. For simplicity, we will compare the cases assuming that the tip shape of sheet 202 is such that the platen is not detected during pre-detection. Note that the operation after detecting the platen 302 with sensor 301A or sensor 301B is the same for detection operation 1 and detection operation 2, and the processing time is also the same. We will also assume that conditions such as the movement speed of carriage 203 are the same.

[0055] Figure 9(a) shows the case of detection operation 1. (1) is the operation in which the carriage 203 starts moving toward the home side in step S202, does not detect the platen 302, and is stopped in step S206 when it is determined that it has moved to the end position. Note that in the case of a configuration with two input ports, sensor 301A and sensor 301B, the detection time will be the same as detection operation 1 even when the sheet width is wide.

[0056] Figure 9(b) shows the case of detection operation 2. (2) is the operation in step S302 in which the carriage 203 starts moving toward the home side, and without detecting the platen 302, it is determined that it has moved to the switching position and the carriage 203 is stopped. (3) is the operation in step S307 in which the home-side sensor 301A is moved to a position slightly away from the switching position. Sensor 301A will move to the range detected by sensor 301B. (4) is the operation in step S308 in which the carriage 203 starts moving toward the home side, and without detecting the platen 302 with sensor 301A, it is determined in step S312 that it has moved to the end position and the carriage 203 is stopped.

[0057] At this time, the time taken for detection operation 1 (1), during which the carriage 203 moves a distance equivalent to the width of the sheet 202, and the sum of detection operation 2 (2) and (4) are approximately the same, excluding the overlapping range. Therefore, detection operation 1 can be shortened by the time taken for detection operation 2 (3).

[0058] As described above, even with two sensors, the device will perform either detection using one sensor or detection using both sensors, depending on the width of the sheet. This allows for the provision of a recording device that can efficiently detect the shape of a sheet even with a housing that is relatively narrow compared to the movement range of the carriage.

[0059] (Embodiment 2) Embodiment 2 of the present invention will now be described. Since the basic pre-cutting operation is the same as in Embodiment 1, only the differences will be described.

[0060] In the recording device 100, regardless of the size of the sheet 202, the sheet 202 is fed by center-reference feeding, where the center of the sheet 202 in the width direction passes through the center position in the width direction of the transport path (PC in Figure 10).

[0061] The flowchart in Figure 6 described in Embodiment 1 and the flow of the pre-cutting operation are the same, but only the determination method in step S102 differs from Embodiment 1.

[0062] Specifically, the CPU 128 compares the value obtained by adding the width of the sheet 202 (WP) divided by 2 to the center position (PC) in the width direction of the transport path (PC) (PC+WP / 2) with the value obtained by subtracting the width of the carriage 203 (WC) from the limit position (PA) where the carriage 203 can move toward the away side (PA). If PC+WP / 2 does not exceed PA-WC, the CPU 128 determines that pre-detection is possible with only the home-side sensor 301A. Since the only variable is the width of the sheet 202 WP, the detection operation will be switched based on the width WP. If it is determined that pre-detection can be performed with one sensor, the process proceeds to S103; if pre-detection is to be performed with two sensors, the process proceeds to S104.

[0063] As described above, it is possible to provide a recording device that can efficiently detect the shape of a sheet even with a housing that is relatively narrow in width relative to the movement range of the carriage. [Explanation of Symbols]

[0064] 203 Carriage 204 Conveyor Roller 301A Sensor (Home side) 301B Sensor (away side)

Claims

1. A conveying means for conveying a sheet including a first sheet and a second sheet that is narrower than the first sheet, A recording means for recording an image on a sheet transported by the aforementioned transport means, A carriage that moves in a second direction opposite to the first direction toward the second end of the sheet conveyed by the conveying means, A recording device comprising, A first sensor is provided on the carriage to detect the sheet, The first sensor and the second sensor, which is positioned on the carriage at a distance in the first direction and detects the sheet, A switching means that switches so that only one of the first sensor and the second sensor is connected to the port, A recording device characterized by comprising control means that performs a detection operation in which the first end side of the first sheet is detected by a signal from a first sensor connected to the port, and the second end side of the first sheet is detected by a signal from a second sensor connected to the port.

2. The recording device according to claim 1, characterized in that the range of movement of the carriage is less than the sum of the width of the carriage in the first direction and the width of the largest sheet that can be transported by the transport means.

3. The recording device according to claim 1, characterized in that it calculates the width of the sheet based on the position of the first end detected by the first sensor and the position of the second end detected by the second sensor.

4. The recording device according to claim 1, characterized in that a sheet is supplied to the conveying means from a roll around which the sheet is wound.

5. The recording device according to claim 1, characterized in that the position of the first end is the same regardless of the width of the sheet in the first direction.

6. The recording device according to claim 1, wherein the recording means is a recording head that ejects ink onto a sheet, and the carriage is equipped with the recording head.

7. A maintenance unit for performing maintenance on the recording head is provided outside the transport path through which the transported sheets pass. The recording device according to claim 6, characterized in that the first end is on the side of the maintenance unit.

8. The recording device according to claim 1, characterized in that, when detecting the first end, the control means moves the first sensor in a first direction and then moves it in a second direction to cause the first end to be detected by the first sensor.

9. In the case of the second sheet, the recording device according to claim 1 is characterized in that the control means causes the first sensor to detect the side of the first end of the second sheet, and then causes the first sensor to detect the side of the second end of the second sheet.

10. The recording device according to claim 1, further comprising a cutter for cutting a sheet conveyed in the aforementioned conveying direction.

11. The recording device according to claim 1, characterized in that, after the detection operation, the control means determines whether to detect the sheet using only the first sensor or to detect the sheet using both the first and second sensors.

Images