JP2009249125A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent fed papers from skewing during conveyance. <P>SOLUTION: Driven rollers SR1 opposed to driving rollers DR1 positioned at a center area and right and left areas of a paper feeding port 105 via a guide path are elastically energized by contact parts 331, 341, and brought into contact with the driving rollers DR1, so as to adjust a contact force of the contact parts 331, 341 energizing the right and left driven rollers SR1 with a variable part 351. The variable part 351 is displaced according to rightward and leftward deviation of a paper feeding position of the paper to the paper feeding port 105, so as to make the contact force of the right and left contact parts 331, 341 variable. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a printer capable of supplying an arbitrary position in the width direction of a paper feed port.

  2. Description of the Related Art Conventionally, a technique for correcting skew feeding of a sheet inserted and fed into a sheet feeding port (see Patent Documents 1 and 2) has been widely applied to printers. This is because if the sheet is conveyed in an oblique state, problems such as printing misalignment and sheet jamming occur. As an example of such a skew correction technique, there is known a technique in which oblique sheets are aligned by abutting the sheet against a pair of conveying rollers that start conveying the sheet.

  The skew-corrected sheet is started to be conveyed by the rotation of the abutting conveyance roller pair. FIG. 12 is a front view illustrating a state in which a sheet is conveyed by a pair of conveying rollers. The conveyance roller pair 14 includes a lower drive roller 14a that rotates by driving a motor, and a driven roller 14b that is provided so as to be able to contact with and separate from the drive roller 14a. At this time, the driven roller 14 b is elastically pressed toward the drive roller 14 a by one end of the torsion spring 13. A transport roller pair having a similar configuration is also provided on the back side in the transport direction of the transport roller pair 14, and this driven roller is also pressed by the other end of the torsion spring 13. The torsion spring 13 is wound around and supported by the torsion spring shaft 12 held by the left and right frames 11.

JP-A-11-147622 JP 2002-347991 A

  By the way, when a thick sheet 15 (for example, a slip in which a plurality of sheets are overlapped and pasted on the side) is supplied left-justified, skewed, and transported by the transport roller pair 14, FIG. As shown in FIG. 12, the driven roller 14 b goes up to the left and goes down to the right while the paper 15 is being conveyed. In this state, the pressure of the conveying roller pair 14 is more strongly applied to the right side portion of the paper 15. Then, since the conveyance force of the right part becomes stronger than the left side, the sheet 15 is skewed to the left while being conveyed by the conveyance roller pair 14 as shown in FIG. That is, even if the sheet 15 is skew-corrected by the correction roller, the sheet 15 is skewed again by the start of conveyance.

  An object of the present invention is to prevent a sheet supplied to a sheet feeding port from being skewed when being conveyed by a pair of conveying rollers.

  The printer of the present invention communicates a paper supply port to which a paper is supplied and a paper discharge port from which the paper is discharged to guide the paper, and a print that is arranged in the guide path and executes a printing operation. A drive roller disposed on one surface side of the guide path upstream of the printing section and positioned in a central region and a left and right region of the paper feed port, and a center of the paper feed port A driven roller positioned in a region and a left and right region and facing the drive roller via the guide path, a contact portion that elastically applies a biasing force to the driven roller and contacts the drive roller, A variable portion that contacts the contact portion and changes the urging force of the driven roller, a sensor that detects and outputs a paper feed position with respect to the paper feed port, and the paper feed port based on a detection output of the sensor Left and right of the paper feed position with respect to When the deviation of the variable portion is determined, the driving portion of the variable portion is driven so that the urging force of the abutting portion against the driven roller by the contact of the variable portion is stronger on the opposite side of the sheet than on the opposite side. And a control unit that is displaced by the control.

  According to the present invention, since the contact force of the driven roller varies depending on the position of the paper supplied to the paper feed port, the paper is skewed when the paper supplied to the paper feed port is conveyed by the conveyance roller pair. Can be prevented.

  An embodiment of the present invention will be described with reference to FIGS. The printer of this embodiment is an example applied to the office machine 101.

  FIG. 1 is a perspective view showing the office machine 101. The office machine 101 includes a housing 102 that accommodates each part. A display device 103 (for example, a liquid crystal display) is attached to the front surface of the housing 102. Below the display device 103, a keyboard 104 as an input device is arranged. In a region between the keyboard 104 and the display device 103 in the housing 102, a paper feed port 105 to which paper S1 (see FIG. 2) is supplied is formed.

  FIG. 2 is a side view showing the office machine 101 with a part of the housing 102 cut away. The housing 102 is provided with a paper discharge port 106 communicating with the paper supply port 105 on the upper surface thereof. A rear paper feed port 107 for feeding the web-like continuous paper S <b> 2 is provided on the rear surface of the paper discharge port 106. A paper discharge tray 108 is rotatably mounted on the upper surface of the housing 102 so as to be positioned behind the paper discharge port 106 and for stacking and holding the sheets S1 discharged from the paper discharge port. Yes.

  Inside the housing 102, a guide path 109 that connects the paper feed port 105 and the paper discharge port 106 is provided. The guide path 109 includes a pair of an upper paper guide 110 and a lower paper guide 111 that are arranged to face each other with a predetermined gap. The guide path 109 having such a configuration connects the paper feed port 105 and the paper discharge port 106 in a curved shape.

  In a region on the discharge path 106 side of the guide path 109, a printing unit 114 that is built in the housing 102 and executes a printing operation is disposed. The printing unit 114 has a structure in which a platen 115 and a dot head 116 are arranged to face each other via a guide path 109.

  The guide path 109 is provided with a plurality of conveyance roller pairs FR arranged via the guide path 109. These conveyance roller pair FR is configured by a driving roller DR and a driven roller SR. Regarding the conveyance roller pair FR, the first conveyance roller pair FR1 (first driving roller DR1 and first driven roller SR1) and the second conveyance roller pair FR2 (second driving roller DR2 and second driving roller DR1) are arranged from a position close to the sheet feeding port 105. 2 driven rollers SR2), a third conveying roller pair FR3 (third driving roller DR3 and third driven roller SR3), and a fourth conveying roller pair FR4 (fourth driving roller DR4 and fourth driven roller SR4). The first transport roller pair FR1, the second transport roller pair FR2, and the third transport roller pair FR3 are sequentially positioned in a region from the paper feed port 105 to the printing unit 114. The first conveyance roller pair FR1 functions as a roller pair that starts conveyance of the sheet S1. The fourth transport roller pair FR4 is positioned between the printing unit 114 and the paper discharge port 106, and functions as a paper discharge roller pair.

  The driving roller DR included in each pair of conveyance rollers FR is rotated under driving control by the control unit 151 (see FIG. 8) of the office machine 101. As a result, the sheet S1 inserted from the sheet feeding port 105 is conveyed along the guide path 109.

  A tractor 112 is disposed on the back surface of the housing 102. The tractor 112 includes a pin belt (not shown) that is movably wound around a drive shaft 113a and a driven shaft 113b. The pin belt rotates integrally with the drive shaft 113a, so that the continuous paper S2 is guided through the guide path. Paper is fed to 109. In addition, a changer 117 is provided at a connecting portion between the tractor 112 and the guide path 109 so as to be able to switch between transport by the transport roller pair FR and transport by the tractor 112.

  Here, a part formed by each part from the paper feed port 105 to the second transport roller pair FR2 is referred to as a paper feed part 201 (see FIG. 3). Next, details of the sheet feeding unit 201 will be described.

  FIG. 3 is a side view showing the paper feeding unit 201. FIG. 4 is a plan view showing the paper feed unit 201. FIG. 5 is a front view of the sheet feeding unit 201 as viewed from the sheet feeding port 105 side. FIG. 6 is a perspective view illustrating a part of the sheet feeding unit 201. 4 to 6, a part of each part shown in FIG. 3 is omitted.

  As shown in FIG. 3, a correction roller 251 is disposed in a region on the upper paper guide 110 side in the region between the paper feed port 105 and the first transport roller pair FR1 in the guide path 109. The correction roller 251 is configured by providing a correction roller shaft 253 with a hammer wheel 252 provided with a plurality of urethane flanges 252a on the outer peripheral portion.

  As shown in FIG. 3, a skew sensor 271 is embedded in the lower paper guide 111 at a position facing the correction roller 251. The skew sensor 271 is a sensor that detects and outputs that the sheet S1 is positioned on the upper surface thereof. The detection output of the skew sensor 271 is input to the control unit 151 (see FIG. 8) of the office machine 101. When the skew sensor 271 detects the sheet S1, the detection output input to the control unit 151 changes from “high” to “low”. The sheet S1 supplied to the sheet feeding port 105 is first sandwiched between the skew sensor 271 and the correction roller 251. At this time, the fly 252a of the flywheel 252 is in contact with the upper surface of the sheet S1.

  As shown in FIG. 3, with respect to the correction roller 251, a plurality of flywheels 252 are fixed to the correction roller shaft 253 at regular intervals. Therefore, as the correction roller shaft 253 rotates, the hour wheel 252 also rotates. Here, the correction roller shaft 253 is rotatably held by a frame FL included in the office machine 101.

  As shown in FIG. 4, a shaft gear 225 is fitted and fixed on the right side (right side in FIG. 4) of the correction roller shaft 253 when viewed from the paper feed port 105 side. The shaft gear 225 meshes with the motor gear 221 that is fitted and fixed to the cam shaft of the motor 211. Therefore, the correction roller 251 rotates when the rotational force of the motor 211 is transmitted via the motor gear 221 and the shaft gear 225. Further, a first belt pulley BP1 described later is fitted and fixed to the correction roller shaft 253 so as to be adjacent to the shaft gear 225. The motor 211 is built in the office machine 101 and is a pulse motor as an example.

  As shown in FIG. 4, five skew sensors 271 are provided along the correction roller shaft 253 at positions where the skew wheels 252 do not face each other (for example, a position between the honeycomb wheels 252). Hereinafter, the five skew sensors 271 are referred to as a skew sensor 271a, a skew sensor 271b, a skew sensor 271c, a skew sensor 271d, and a skew sensor 271e from the left side in FIG.

  As shown in FIG. 4, when a sheet S1 having a sheet width that is less than the full width of the sheet feeding port 105 is supplied to the sheet feeding port 105 in a left-justified manner, only the skew sensors 271a, 271b, and 271c have the sheet S1. It detects that it is located on the upper surface and outputs it. On the other hand, when the same paper S1 is supplied to the paper supply port 105 right-justified, only the skew sensors 271c, 271d, and 271e detect and output that the paper S1 is positioned on the upper surface thereof.

  As shown in FIG. 3, the first conveying roller pair FR1 (first driving roller DR1, first driven roller SR1) downstream of the correction roller 251 and the skew sensor 271 (on the right side in FIG. 3) on the guide path 109. And a second conveying roller pair FR2 (second driving roller DR2, second driven roller SR2).

  As shown in FIG. 5, the first drive roller DR1 included in the first transport roller pair FR1 is configured by providing a plurality of first drive roller bodies DR1B on one first drive roller shaft DR1S. Similarly, the first driven roller SR1 is also configured by providing a plurality of first driven roller bodies SR1B at the same interval as the first drive roller body DR1B on one first driven roller shaft SR1S. The first drive roller DR1 and the first driven roller SR1 are disposed at positions where the first drive roller body DR1B and the first driven roller body SR1B face each other.

  Although not shown in detail, the second transport roller pair FR2 also has the same configuration as the first transport roller pair FR1. That is, the second drive roller DR2 is configured by providing a plurality of second drive roller bodies DR2B on one second drive roller shaft DR2S, and the second driven roller SR2 is also a single second driven roller shaft SR2S. A plurality of second driven roller bodies SR2B are provided at the same interval as the second driving roller body DR2B, and are arranged opposite to the second driving roller body DR2B and the second driven roller body SR2B.

  In the present embodiment, the first drive roller DR1 includes four first drive roller bodies DR1B, that is, one first drive roller body DR1B located in the left region of the sheet feed port 105, and the center of the sheet feed port 105. It has two first drive roller bodies DR1B located in the area and one first drive roller body DR1B located in the right area of the paper feed port 105. Thus, the first drive roller DR1 is positioned in the central region and the left and right regions of the paper feed port 105.

  The first driven roller SR1 facing the first drive roller DR1 has the same configuration. In other words, the first driven roller SR1 is positioned in the central region of the four first driven roller bodies SR1B, that is, the first driven roller body SR1B located in the left region of the paper feed port 105 and the paper feed port 105. It has two first driven roller bodies SR1B and one first driven roller body SR1B located in the right region of the paper feed port 105. Thus, the first driven roller SR1 is positioned in the central region and the left and right regions of the sheet feeding port 105.

  Further, the second drive roller DR2 and the second driven roller SR2 included in the second transport roller pair FR2 have the same configurations as the first drive roller DR1 and the first driven roller SR1, respectively.

  The first drive roller shaft DR1S and the second drive roller shaft DR2S are rotatably held by a frame FL, and a pulley (not shown) is provided on one end side of each of the pulleys (not shown). ) Is a pulley belt (not shown). Therefore, the first drive roller DR1 and the second drive roller DR2 rotate together in an integrated manner. The first drive roller shaft DR1S rotates by receiving the rotational force of a transport motor (not shown) built in the office machine 101. That is, the first driving roller DR1 and the second driving roller DR2 are rotated in an integrated manner by the rotational drive of the transport motor (not shown). Note that the rotational force of the transport motor (not shown) may be transmitted to the second drive roller shaft DR2S.

  As shown in FIG. 6, both ends of the first driven roller shaft SR1S are inserted into a long hole FL1 which is formed in the frame FL and which is long in the vertical direction. Thus, the first driven roller shaft SR1S is rotatably held with play in the vertical direction. Similarly, the second driven roller shaft SR2S (see FIG. 3 and the like) is also inserted into a vertically long elongated hole (not shown) formed in the frame FL so that the second driven roller shaft SR2S can freely rotate with play in the vertical direction. Is retained. Therefore, the first driven roller body SR1B comes into contact with the opposing first driving roller body DR1B due to its own weight, and the second driven roller body SR2B similarly comes into contact with the opposing second driving roller body DR2B due to its own weight. is doing.

  As shown in FIG. 3, a torsion spring 331 is disposed above the first driven roller shaft SR1S and the second driven roller shaft SR2S. The torsion spring 331 is wound around and supported by a torsion spring shaft 341 located on the upper surface side of the upper paper guide 110. As shown in FIG. 4, the torsion spring 331 is a position between the first driven roller bodies SR1B (or the second driven roller bodies SR2B), and both ends thereof are connected to the first driven roller shaft SR1S and the second driven roller body SR1B. A plurality (five in this embodiment) are arranged at positions in contact with the driven roller shaft SR2S. At this time, as shown in FIG. 6, both ends of the torsion spring shaft 341 are inserted into a long hole FL2 which is formed in the frame FL and which is long in the vertical direction. Thus, the torsion spring shaft 341 is held with play in the vertical direction. Therefore, the torsion spring 331 wound around and supported by the torsion spring shaft 341 has its own weight (including the weight of the torsion spring shaft 341), and both ends thereof are the first driven roller shaft SR1S and the second driven roller shaft SR2S. Touching.

  As shown in FIG. 5, a pair of cams 351 (a cam 351 a and a cam 351 b) are disposed in contact with the torsion spring shaft 341 at the upper positions on both end sides of the torsion spring shaft 341 that protrude from the frame FL. . Such a cam 351 is fixed to both end portions of one cam shaft 352 rotatably held by the frame FL at a position above the torsion spring shaft 341. As the cam shaft 352 rotates, the cams 351 fixed to both ends also rotate together.

  As shown in FIG. 6, the torsion spring shaft 341 and the first driven roller shaft SR1S are held up and down while the cam shaft 352 does not play up and down, and movement restrictions other than rotation. And held in the frame FL. Therefore, the torsion spring shaft 341 is pressed downward by the cam 351 that contacts the torsion spring shaft 341. Since the torsion spring shaft 341 is pressed, both ends of the torsion spring 331 included in the torsion spring shaft 341 press the first driven roller shaft SR1S and the second driven roller shaft SR2S downward. (See FIG. 3 etc.). Further, the first driven roller body SR1B comes into contact with the corresponding first driving roller body DR1B in an elastically pressed state, and the second driven roller body SR2B is also in contact with the corresponding second driving roller body DR2B. The contact is made in an elastically pressed state.

  As shown in FIG. 4, a second belt pulley BP <b> 2 is provided at one end of the cam shaft 352. The second belt pulley BP2 is positioned at a position in series with the first belt pulley BP1 provided at one end of the correction roller shaft 253. A pulley belt PBL is stretched between the first belt pulley BP1 and the second belt pulley BP2. As a result, the first belt pulley BP1 and the second belt pulley BP2 rotate together in an integrated manner. At this time, since the first belt pulley BP1 is rotated by driving the motor 211, the second belt pulley BP2 is also driven by the driving of the motor 211 to transmit the first belt pulley BP1. And rotate together. That is, the correction roller 251 and the cam 351 rotate in conjunction with each other by driving the motor 211 with the same motor 211.

  As shown in FIG. 4, the second belt pulley BP2 is provided on the camshaft 352 via an electromagnetic clutch EMC. The electromagnetic clutch EMC freely connects and disconnects the second belt pulley BP2 with respect to the cam shaft 352. When the electromagnetic clutch EMC is in the connected state, the rotational power of the second belt pulley BP2 is transmitted to the cam shaft 352, and the cam shaft 352 rotates integrally with the second belt pulley BP2. On the other hand, when the electromagnetic clutch EMC is in the disconnected state, the transmission of the rotational power of the second belt pulley BP2 to the cam shaft 352 is released. Such connection and disconnection of the electromagnetic clutch EMC are executed under the control of the control unit 151 (see FIG. 8). In addition, when the electromagnetic clutch EMC is in a disconnected state, the rotation operation of the cam shaft 352 is restricted, and the electromagnetic clutch EMC is in a disconnected state at normal times.

  By the way, as shown in FIG. 3, when the cam 351 is viewed from the side, the outer peripheral shape thereof is not a complete circular shape, and the distance from the axial center to the outer periphery varies. The outer peripheral surface of the cam 351 of the present embodiment has a cam surface 353 (cam surfaces 353a, 353S) including a shortest portion 353S having the shortest distance from the cam shaft 352 and a longest portion having the longest distance from the cam shaft 352. The cam surface 353b).

  FIG. 7 is a schematic diagram showing the rotation state of the cam 351. One cam 351a and the other cam 351b are members of the same shape. A cam 351 a and a cam 351 b having the same shape are fixedly attached to both end portions of one cam shaft 352. At this time, the shortest part 353Sa of one cam 351a and the shortest part 353Sb of the other cam 351b are attached to positions that are opposite to the cam shaft 352. Therefore, the pair of cams 351 (cam 351a, cam 351b) are connected to the first driven roller shaft SR1S and the second driven roller shaft SR2S of the torsion spring shaft 341 by the cam surfaces 353 (cam surface 353a, cam surface 353b). The phase of the pressing force is reversed. The cam 351 and the cam shaft 352 may be integrally formed.

  Further, as shown in FIG. 7, a rotational position sensor HPS which is a transmission type sensor is disposed adjacent to one cam 351b (see also FIGS. 4 and 6). The rotational position sensor HPS is disposed at a position where the cam 351b enters and light is blocked by this, and is fixed to the frame FL or the like. The rotational position sensor HPS is not always light-blocked by the cam 351b, but the light block is released depending on the rotational position of the cam 351b.

  That is, as shown in FIG. 7A, in the state where the cam 351b is positioned at the rotational position where the shortest portion 353Sa on the cam surface 353a faces the rotational position sensor HPS, the cam 351b enters the groove of the rotational position sensor HPS. Is released, and the rotational position sensor HPS is in a light transmitting state. The detection output of the rotational position sensor HPS is input to the control unit 151 (see FIG. 8) of the office machine 101. As the rotational position sensor HPS changes from the light blocking state to the light transmitting state, the detection output of the rotational position sensor HPS input to the control unit 151 changes from “low” to “high”.

  When the cam 351 is positioned at the rotational position shown in FIG. 7A, the distance from the shaft center of the cam 351 to the cam surface 353 that contacts the torsion spring shaft 341 (not shown in FIG. 7) Both 351a and cam 351b are equal. Therefore, the left-right balance of the pressing state to the torsion spring shaft 341 by the cam 351 is equal. The left and right balance of the pressing of the first driven roller SR1 and the second driven roller SR2 by the torsion spring 331 is also equal. Hereinafter, the rotational position of the cam 351 shown in FIG. 7A is referred to as a “reference position”.

  Next, as shown in FIG. 7B, the state where the cam 351b is positioned at the rotational position where the shortest portion 353Sb contacts the torsion spring shaft 341 will be described. At this time, the cam 351b enters the groove of the rotational position sensor HPS and is in a light blocking state, and the detection output of the rotational position sensor HPS input to the control unit 151 is “low”.

  When the cam 351 is positioned at the rotational position shown in FIG. 7B, the distance from the shaft center of the cam 351 to the cam surface 353 that contacts the torsion spring shaft 341 (not shown in FIG. 7) The distance at 351b is shorter than the distance at cam 351a. Therefore, the left-right balance of the pressing state of the cam 351 against the torsion spring shaft 341 is stronger on the left side (cam 351a side, upper side in FIG. 7) than on the right side (cam 351b side, lower side in FIG. 7). . At this time, the pressing of the first driven roller SR1 and the second driven roller SR2 by the torsion spring 331 is also stronger on the left side than on the right side. Hereinafter, the rotational position of the cam 351 shown in FIG. 7B is referred to as a “left-justified position”.

  Next, as shown in FIG. 7C, the state where the cam 351a is positioned at the rotational position where the shortest portion 353Sa contacts the torsion spring shaft 341 will be described. Also at this time, the cam 351b enters the groove of the rotational position sensor HPS and is in a light blocking state, and the detection output of the rotational position sensor HPS input to the control unit 151 is “low”.

  In the state where the cam 351 is positioned at the rotational position shown in FIG. 7C, the distance from the shaft center of the cam 351 to the cam surface 353 that contacts the torsion spring shaft 341 (not shown in FIG. 7) The distance at 351a is shorter than the distance at cam 351b. Therefore, the right / left balance of the pressing state of the cam 351 against the torsion spring shaft 341 is stronger on the right side (cam 351b side, lower side in FIG. 7) than on the left side (cam 351a side, upper side in FIG. 7). . At this time, the pressure on the first driven roller SR1 and the second driven roller SR2 by the torsion spring 331 is also stronger on the right side than on the left side. Hereinafter, the rotational position of the cam 351 shown in FIG. 7C is referred to as a “right-justified position”. The “right alignment position” is a position obtained by rotating the cam shaft 352 by 180 ° from the “left alignment position”.

  FIG. 8 is a block diagram showing the electrical connection of the office machine 101. The office machine 101 includes a control unit 151 having a microcomputer configuration that drives and controls each unit. The control unit 151 includes a CPU, a ROM, a RAM, and the like (all not shown). The control device 151 is connected to the display device 103 and the keyboard 104 included in the office machine 101. Further, motors 152 including a motor 211 and a conveyance motor (not shown), sensors 153 including a skew sensor 271 and a rotational position sensor HPS, and an electromagnetic clutch EMC are connected to the control unit 151. The motors 152 are controlled by the control unit 151 to drive. Further, the detection output of the sensors 153 is input to the control unit 151.

  In such a configuration, a process executed by the control unit 151 when a plurality of sheets are stacked and a thick sheet S1 is supplied to the sheet feeding port 105 will be described below.

  FIG. 9 is a flowchart showing a flow of processing when the paper S1 is supplied to the paper supply port 105. First, the control unit 151 of the office machine 101 waits for determination of the supply of the sheet S1 to the sheet feeding port 105 (step S101). At this time, when the sheet S1 is supplied to the sheet feeding port 105 and inserted between the correction roller 251 and the skew sensor 271, the detection output input to the control unit 151 of any one of the skew sensors 271 is “high”. "" To "low". Thereby, the control unit 151 determines that the sheet S1 is supplied to the sheet feeding port 105 (Y in step S101).

  Next, the control unit 151 controls and rotates the motor 211 to rotate the correction roller 251 (step S102). As a result, the sheet S1 inserted between the correction roller 251 and the skew sensor 271 is fed into the guide path 109 with a conveying force applied by the rotating skirt 252a, and the leading edge of the sheet S1 is the first conveying roller pair. It hits FR1. When the sheet S1 hits the first conveying roller pair FR1, the sway 252a around which the correction roller 251 rotates slips between the sheet S1. In this way, the sheets S1 are aligned and skew correction is executed.

  Further, the controller 151 controls the electromagnetic clutch EMC while rotating the motor 211 to displace the cam 351 to the “reference position” (step S103). The control unit 151 determines that the cam 351 is positioned at the “reference position” when the rotational position sensor HPS is in a light transmission state and its detection output becomes “high”. At this time, the control unit 151 keeps the electromagnetic clutch EMC connected until the detection output of the rotational position sensor HPS becomes “high”, and the connection state of the electromagnetic clutch EMC is released when this detection output becomes “high”. To do. Thus, the cam 351 is displaced to the “reference position”. The control unit 151 starts the control for displacing the cam 351 to the “reference position” together with the start of the rotational drive of the motor 211 and finishes until the correction roller 251 makes one rotation.

  Next, the control unit 151 determines the position in the width direction of the sheet S1 supplied to the sheet feeding port 105. In the present embodiment, the control unit 151 determines whether the sheet S1 is supplied to the center of the sheet feeding port 105 (step S104), is supplied to the sheet feeding port 105 with left alignment (step S105), or is right-aligned with the sheet feeding port. It is determined whether it has been supplied to 105 (step S106).

  The fact that the sheet S1 is supplied to the center of the paper feed port 105 is that the detection output of the three skew sensors 271 (skew sensors 271b, 271c, 271d) among the five skew sensors 271 is "high" to "low". Judgment by becoming.

  The fact that the sheet S1 is left-justified and supplied to the sheet feeding port 105 is that the detection outputs of the left three skew sensors 271 (skew sensors 271a, 271b, 271c) out of the five skew sensors 271 are "high" to "low". Judgment by becoming.

  The fact that the sheet S1 is right-justified and supplied to the sheet feeding port 105 is that the detection outputs of the three skew sensors 271 (skew sensors 271c, 271d, and 271e) on the right side among the five skew sensors 271 are "high" to "low". Judgment by becoming.

  When the control unit 151 determines that the sheet S1 has been supplied to the center of the sheet feeding port 105 (Y in step S104), the control unit 151 controls the electromagnetic clutch EMC to further displace the cam 351 without changing the cam 351. Leave it positioned at the “reference position”. Therefore, the left / right balance of the pressure applied to the first driven roller SR1 and the second driven roller SR2 by the torsion spring 331 is equal. Then, the control unit 151 controls and rotates the transport motor to start rotation of the first transport roller pair FR1 and the second transport roller pair FR2 (step S107). As a result, the sheet S1 that is in contact with the first transport roller pair FR1 is drawn and transported to the rotating first transport roller pair FR1.

  If it is determined that the sheet S1 is supplied to the sheet feeding port 105 by left justification (Y in step S105), the control unit 151 controls the electromagnetic clutch EMC again to be in the connected state, and the cam 351 is “left-justified”. It is displaced to “position” (step S108). At this time, the control unit 151 executes control for bringing the electromagnetic clutch EMC into a connected state only for a predetermined time during which the cam 351 at the “reference position” is positioned at the “left-justified position” by the rotation of the cam shaft 352. Thus, the cam 351 is displaced to the “left alignment position”.

  FIG. 10 is a front view showing a state in which the sheet S1 is supplied left-justified. When the thick sheet S1 is supplied to the sheet feeding port 105 in a left-justified manner and enters between the first conveying roller pair FR1, the sheet S1 is provided so as to be able to contact and separate (movable in the vertical direction) with respect to the first driving roller DR1. The first driven roller SR1 can be in a left-up and right-down state when viewed from the paper feed port 105 side. The same applies to the second driven roller SR2. However, according to the present embodiment, at this time, the cam 351 is positioned at the “left-justified position”, and the first driven roller SR1 and the second driven roller SR2 are pressed by the torsion spring 331 on the left side. Since it is stronger than the right side, as shown in FIG. 10, the left-up and right-down state of the first driven roller SR1 and the second driven roller SR2 is eliminated, and the left-right balance becomes equal. Thus, when the sheet S1 is conveyed by the first conveyance roller pair FR1 and the second conveyance roller pair FR2, pressure is equally applied to the sheet S1. Therefore, the sheet S1 supplied left-justified is prevented from skewing to the left while being conveyed by the first conveying roller pair FR1 and the second conveying roller pair FR2, and the conveyed sheet S1 goes straight.

  Returning to the description of FIG. If it is determined that the sheet S1 is right-justified and supplied to the paper feed port 105 (Y in step S106), the control unit 151 controls the electromagnetic clutch EMC to be in a connected state, and sets the cam 351 to the “right-aligned position”. Displace (step S109). At this time, the control unit 151 executes control for bringing the electromagnetic clutch EMC into a connected state only for a predetermined time during which the cam 351 at the “reference position” is positioned at the “right-aligned position” by the rotation of the cam shaft 352. Thus, the cam 351 is displaced to the “right alignment position”.

  FIG. 11 is a front view illustrating a state where the sheet S1 is supplied right-justified. When the thick sheet S1 is right-justified and supplied to the paper feed port 105 and enters between the first conveying roller pair FR1, the first driven roller SR1 is lowered to the left and raised to the right when viewed from the paper feed port 105 side. Can be. However, according to the present embodiment, at this time, the cam 351 is positioned at the “right-aligned position”, and the first driven roller SR1 and the second driven roller SR2 are pressed by the torsion spring 331 on the right side. Since it is stronger than the left side, as shown in FIG. 11, the right-up and left-down states of the first driven roller SR1 and the second driven roller SR2 are eliminated, and the left-right balance becomes equal. Thus, when the sheet S1 is conveyed by the first conveyance roller pair FR1 and the second conveyance roller pair FR2, pressure is equally applied to the sheet S1. Therefore, the sheet S1 supplied right-justified is prevented from being skewed to the right while being conveyed by the first conveyance roller pair FR1 and the second conveyance roller pair FR2, and the conveyed sheet S1 goes straight.

  In the present embodiment, an example is shown in which not only the first driven roller SR1 but also the second driven roller SR2 can freely contact and separate from the opposing drive roller DR (second drive roller DR2). Only the first driven roller SR1 included in the first conveying roller pair FR1 against which the sheet S1 comes into contact may be movable toward and away from the driving roller DR. In this case, with respect to the second driven roller SR2, the second driven roller shaft SR2S is rotatably held by the frame FL without causing play in the vertical direction. For the torsion spring 331, for example, one end on the second driven roller SR2 side may be wound and fixed around the torsion spring shaft 341, and the torsion spring 331 may be held so as not to rotate.

  Further, in the present embodiment, the pair of cams 351 (cam 351a, cam 351b) is connected to the first driven roller shaft SR1S of the torsion spring shaft 341 and the second by the cam surfaces 353 (cam surface 353a, cam surface 353b). Although the phase of the pressing force with respect to the driven roller shaft SR2S is changed by 180 degrees, it may not be 180 degrees. In the present embodiment, the drive source of the correction roller 251 and the drive source of the cam 351 are the same motor 211, but the drive sources may be different.

  As described above, according to the present embodiment, the sheet S1 supplied to the sheet feeding port 105 and subjected to skew correction is prevented from skewing again when being transported by the transport roller pair FR. be able to.

It is a perspective view which shows an office machine. It is a side view which shows a business machine by notching a part of a housing. It is a side view which shows a paper feed part. It is a top view which shows a paper feed part. FIG. 3 is a front view of a sheet feeding unit viewed from a sheet feeding port side. It is a perspective view which shows a part of paper feed part. It is a schematic diagram which shows the rotation state of a cam. It is a block diagram which shows the electrical connection of an office machine. 6 is a flowchart illustrating a processing flow when a sheet is supplied to a sheet feeding port. FIG. 6 is a front view illustrating a state where a sheet is supplied left-justified. FIG. 6 is a front view illustrating a state where a sheet is supplied right-justified. FIG. 6 is a front view illustrating a state in which a sheet is conveyed by a pair of conveyance rollers. FIG. 6 is a plan view illustrating a state in which a sheet is conveyed by a pair of conveyance rollers.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Office machine (printer), 105 ... Paper feed port, 106 ... Paper discharge port, 109 ... Guide route, 114 ... Printing part, 151 ... Control part, 211 ... Motor, 251 ... Correction roller, 271 ... Skew sensor (sensor) , Second sensor), 331 ... torsion spring (contact portion), 351, 351a, 351b ... cam (variable portion), DR1 ... first drive roller (drive roller), DR2 ... second drive roller (drive roller). , EMC ... Electromagnetic clutch, FR1 ... First conveying roller pair (conveying roller pair), FR2 ... Second conveying roller pair (conveying roller pair), S1 ... Paper, SR1 ... First driven roller (driven roller), SR2 ... First 2 driven roller (driven roller)

Claims (5)

A guide path for guiding the paper by connecting the paper supply port to which the paper is supplied and the paper discharge port from which the paper is discharged;
A printing unit that is arranged in the guide path and executes a printing operation;
A driving roller disposed on one surface side of the guide path upstream of the printing unit and positioned in a central region and a left and right region of the paper feed port;
A driven roller positioned in a central region and a left and right region of the sheet feeding port and facing the driving roller via the guide path;
A contact portion that elastically applies a biasing force to the driven roller to contact the drive roller;
A variable portion that comes into contact with the contact portion and varies the urging force against the driven roller;
A sensor for detecting and outputting a paper feed position with respect to the paper feed port;
When it is determined from the detection output of the sensor that the paper feed position of the paper with respect to the paper feed opening is shifted to the left or right, the urging force of the abutting portion against the driven roller by the abutting of the variable portion is a piece of paper. A control unit for displacing the variable unit by controlling the drive source so as to be stronger on the side closer to the opposite side;
Printer with. The variable part is:
A cam that abuts against the abutting portion that imparts a biasing force to the driven roller positioned in the left and right region and varies the phase of the biasing force with respect to the left and right driven rollers;
The controller is
When it is determined from the detection output of the sensor that the paper feeding position of the paper with respect to the paper feeding opening is shifted to the left or right, the urging force of the abutting portion against the driven roller due to the abutting of the cam is a deviation of the paper. The cam is rotated by control of its drive source so that it is stronger on the side than on the opposite side,
The printer according to claim 1. A pair of conveying rollers having the driving roller and the driven roller;
It is disposed at a position in contact with one surface of the paper supplied to the paper supply port, and feeds the paper supplied to the paper supply port to the guide path by rotation, and the leading edge of the fed paper is A correction roller that causes slippage between the paper and the paper when it strikes the pair of transport rollers;
A second sensor for detecting and outputting a paper supply to the paper feed port;
With
The control unit controls the driving source of the correction roller to rotate the correction roller when it is determined by the detection output of the second sensor that the paper has been supplied to the paper supply port.
The printer according to claim 2. The drive source of the cam and the drive source of the correction roller are the same motor,
An electromagnetic clutch that allows the power from the motor to be transmitted and released under the control of the control unit;
The printer according to claim 3. The conveying roller pair is
A first conveyance roller pair against which a sheet to which a conveyance force is given by rotation of the correction roller abuts, and a second conveyance roller pair disposed on the downstream side of the guide path from the first conveyance roller pair,
The contact portion is
Both ends thereof include torsion springs that contact the driven rollers of the first conveying roller pair and the driven rollers of the second conveying roller pair,
The printer according to claim 4.

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