JP2011225325A - Sheet-shaped material feeding apparatus and document reading device equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide constitution for simply switching a rotating direction of a feed roller used for conveyance in a sheet-shaped material feeding apparatus.SOLUTION: The automatic document feeding apparatus (ADF) includes a conveyance roller which can bidirectionally rotate, a motor 90 which produces torque for driving the conveyance roller, a power branching gear 94, transmission gears 95 to 98, an electromagnetic clutch 91, the number of gear sheets adjusting part 99 and a control part. The transmission gears 95 to 98 transmit the torque to the conveyance roller. The electromagnetic clutch 91 can switch whether the torque is transmitted to the power branching gear 94. The number of gear sheets adjusting part 99 can change the number of transmission gear sheets through which the torque is transmitted to the conveyance roller. When a rotation direction of the rotating conveyance roller is switched, the control part controls the electromagnetic clutch 91 at first to intercept the torque and further the number of transmission gear sheets through which the torque is transmitted is increased or reduced by one sheet. Then the torque is transmitted by controlling the electromagnetic clutch 91.

Description

  The present invention relates to a sheet-like material feeding device and an original reading device that reads image information while conveying an original with the sheet-like material feeding device.

  2. Description of the Related Art Conventionally, a sheet-type material feeding apparatus of a type that separates and conveys one sheet from a plurality of sheet-shaped materials set in an overlapping manner is known. This sheet-like material feeding device is used in, for example, a document reading device that transports documents one by one and reads the image information, and an image forming apparatus that transports sheets one by one to form an image. .

  Such a sheet-like material feeding device is known to have a switchback function for reversing the conveying direction of the sheet-like material. By providing the switchback function, for example, both sides of the original can be read and both sides of the paper can be printed. In addition, a sheet-like feeding device having a switchback function may require a configuration that switches the rotation direction of another conveyance roller (for example, a switchback roller) while rotating a certain conveyance roller in a certain direction. As this configuration, there is known a mechanism for rotating a transport roller in a fixed direction regardless of the rotation direction of the motor. Patent Document 1 and Patent Document 2 disclose a transport device provided with this type of mechanism.

  The configuration disclosed in Patent Document 1 includes a swing gear that swings according to the rotation direction of the motor. By this swing gear, different power transmission paths are selected according to the rotation direction of the motor. Since this power transmission path differs in the number of gears that are configured by an odd number, the rotation direction of the transport roller can be made constant regardless of the rotation direction of the motor.

  The configuration of Patent Document 2 includes two one-way clutches. The one-way clutch that transmits drive when the motor rotates in one direction is a spring clutch, and the one-way clutch that transmits drive when the motor rotates in the other direction. It is a pendulum type. As a result, the number of gears used can be made different between when the motor rotates in one direction and when the motor rotates in the other direction, so the rotation direction of the transport roller can be made constant regardless of the rotation direction of the motor. it can.

Japanese Patent Laid-Open No. 10-72139 JP 2000-327150 A

  However, in the configurations of Patent Document 1 and Patent Document 2, it is necessary to provide a motor capable of switching the rotation direction. In order to switch the rotation direction of the transport roller without switching the rotation direction of the motor, two electromagnetic clutches and the like are required, which leads to a complicated configuration and an increase in cost.

  The present invention has been made in view of the above circumstances, and its main object is an apparatus for conveying a sheet-like material, and provides a configuration for easily switching the rotation direction of a feed roller used for conveyance. There is.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to the 1st viewpoint of this invention, the sheet-like material feeder of the following structures is provided. That is, the sheet-shaped material feeding device includes a sheet-shaped material conveyance path, a feeding roller, a driving device, a plurality of transmission gears, a clutch, a gear number adjusting unit, and a control unit. The sheet-like material conveyance path is for conveying the sheet-like material. The feed roller is disposed in the sheet-like material conveyance path and is rotatable in both directions. The driving device generates a rotational force for driving the feed roller. The plurality of transmission gears transmit the rotational force to the feed roller. The clutch can be switched between transmitting and interrupting the rotational force to the transmission gear. The gear number adjusting unit can change the number of transmission gears through which the rotational force is transmitted to the feed roller. The control unit controls the clutch and the gear number adjusting unit. The controller performs a process including a first step, a second step, and a third step when switching the rotation direction of the rotating feed roller. In the first step, the rotational force is interrupted by controlling the clutch. In the second step, the number of transmission gears through which the rotational force passes is changed from an odd number to an even number or from an even number to an odd number by controlling the gear number adjusting unit. In the third step, the rotational force in the same direction as in the first step is transmitted by controlling the clutch.

  That is, in order to switch the rotation direction of the feed roller without switching the rotation direction of the motor, it is necessary to provide two clutches. In this regard, by using the above configuration, the rotation direction of the feed roller can be switched without switching the rotation direction of the motor with only one clutch, so that the sheet-like material feeding device is made compact and low-cost. Can do. Further, when the number of transmission gears through which the rotational force of the drive device passes is changed, the rotational force is blocked by the clutch, so that the teeth of the transmission gear can be prevented from being damaged.

  The sheet-shaped material feeding device preferably has the following configuration. That is, the gear number adjusting unit includes an oscillating body and an oscillating body driving unit. The oscillating body is attached such that the transmission gear can rotate relative to the oscillating body. The rocking body drive unit switches the number of transmission gears through which the rotational force passes by rocking the rocking body.

  Thereby, the rotation direction of the feed roller can be switched with a simple configuration.

  In the sheet-like material feeding device, the member located at the center of the feed roller or the member located at the center of the transmission gear that is not connected to the rocking body, and the rocking body are brought into contact with each other to bring the It is preferable to position the oscillator.

  Thereby, since the rocking body can be positioned with a simple configuration, it is possible to realize a sheet-shaped material feeding device that is compact and further inexpensive.

  The sheet-shaped material feeding device preferably has the following configuration. That is, the sheet-like material feeding device includes a second feeding roller. The oscillating body can switch the number of the transmission gears that pass therethrough by rotating around the oscillating shaft. The swing shaft includes a first drive transmission path for transmitting the rotational force from the drive device to the feed roller, a second drive transmission path for transmitting the rotational force from the drive device to the second feed roller, It is arranged at the branch point. The transmission gear includes a rotational force branching gear that is arranged so that the rotation axis coincides with the swing axis.

  As a result, the position of the rotational force branch gear does not change even when the oscillator is oscillated, so that the rotational force is also transmitted to the second feed roller while the rotational force is being transmitted to the first feed roller. Will be. Accordingly, the rotation and stop timings of the feed roller and the second feed roller can be made uniform.

  In the sheet material feeder, the second feed roller is preferably a registration roller that corrects the skew of the sheet material.

  Thereby, since a drive device and a clutch can be shared with a feed roller, a number of parts can be reduced and a sheet-like material feeder can be made low-cost.

  According to a second aspect of the present invention, there is provided a document reading apparatus including the sheet-shaped material feeding device and a reading unit that reads image information of a document as a sheet-shaped material.

  Thereby, a compact and low-cost document reading apparatus can be realized.

1 is an external perspective view of a multifunction peripheral according to an embodiment of the present invention. FIG. 3 is a front cross-sectional view showing the configuration of the image scanner device. The schematic diagram explaining the introduction path | route and the discharge path for single sides | surfaces. The schematic diagram explaining a 1st inversion path | route. The schematic diagram explaining a 2nd inversion path | route. The schematic diagram explaining the discharge path for both surfaces. The front view which shows the drive transmission path | route when rotating a conveyance roller to one direction. The front view which shows the drive transmission path | route when rotating a conveyance roller to another direction. The front view which shows a mode that a rocking | fluctuation bracket rock | fluctuates. The block diagram which shows the electric constitution of ADF.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external perspective view of a multifunction machine 1 according to an embodiment of the present invention.

  The multifunction device 1 has a copy function and a facsimile function, and an image scanner device (document reading device) 11 that functions as a book scanner and an auto document feed scanner is provided on the upper portion of the multifunction device 1. The multifunction machine 1 also includes an operation panel 12 for instructing the number of copies, a facsimile transmission destination, a document reading, and the like.

  The multifunction device 1 further includes a multifunction device main body 13 including an image forming unit that forms an image on a sheet as a recording medium, and a sheet feeding cassette 14 that sequentially supplies the sheet. The multifunction machine main body 13 includes a transmission / reception unit (not shown) for transmitting image information via a communication line.

  Next, the image scanner device 11 provided in the multifunction machine 1 will be described with reference to FIG. FIG. 2 is a front sectional view showing the configuration of the image scanner device 11. The front view in the present embodiment can also be expressed as a view seen in the width direction of the conveyed document.

  As shown in FIG. 2, the image scanner device 11 includes a document table cover 21, a platen glass 22, and a contact glass 23. The document table cover 21 is provided with an automatic document feeder (sheet material feeder, auto document feeder, ADF) 24. Further, the image scanner device 11 includes a scanner unit 25 for reading image information of the original 100 below the platen glass 22 and the contact glass 23.

  The scanner unit 25 includes a carriage 110 that can move in the left-right direction inside the document table. In the carriage 110, a light source 111, a plurality of reflecting mirrors 112, a condenser lens 113, and a charge coupled device (CCD) 114 are arranged. The light source 111 irradiates the read original with light, and the reflected light from the read original is reflected by a plurality of reflecting mirrors 112 and then converges through the condenser lens 113 to form an image on the surface of the CCD 114. Then, the CCD 114 converts the incident convergent light into an electrical signal and outputs it.

  Further, as shown in FIG. 2, the ADF 24 provided in the document table cover 21 includes a paper feed tray 52 provided above the document table cover 21 and a paper discharge tray provided below the paper feed tray 52. 53. In addition, a document transport path (sheet-shaped material transport path) 40 that connects the paper feed tray 52 and the paper discharge tray 53 is formed inside the ADF 24.

  When the user operates the operation panel 12 shown in FIG. 1 to instruct to use the image scanner device 11 as an auto document feed scanner, the original 100 set on the paper feed tray 52 is placed on the original conveyance path 40. It is conveyed one by one along. Then, when the document 100 transported along the document transport path 40 passes through the glass surface (reading position) of the contact glass 23, the image information of the document 100 is read by the scanner unit 25. Thereafter, the document 100 is transported along the document transport path 40 and is discharged to the paper discharge tray 53.

  On the other hand, when the image scanner device 11 is used as a book scanner, the user places a book document to be read on the platen glass 22. Then, the book document is pressed from above by the platen sheet 51 arranged at the lower part of the ADF 24 and fixed so as not to move. In this state, the scanner unit 25 performs reading while moving in the left-right direction, whereby the image information of the book document is read.

  Next, the internal configuration of the ADF 24 will be described in detail. In the following description, when viewed from the front, the side with the paper feed tray 52 may be simply referred to as “right side”, and the opposite side in front view may be simply referred to as “left side”.

  In the ADF 24 according to the present embodiment, the path through which the document 100 is conveyed differs when reading only one side (first surface) of the document 100 and when reading both surfaces (first surface and second surface) of the document 100. It is configured as follows. First, a path for reading only one side of the document 100 and members arranged in the path will be described with reference to FIGS. FIG. 3 is a schematic diagram illustrating the introduction path 41 and the single-side discharge path 43.

  When only one side of the original 100 is read, as shown in FIG. 3, an introduction path 41 for guiding the original 100 to the reading position and a single-sided discharge for guiding the original 100 from the reading position to the paper discharge tray 53. The document 100 is conveyed along the path 43.

  In the introduction path 41, a pickup roller 30, a separation roller 31, a registration roller 32, a triple roller 33, and a conveyance roller (feed roller) 34 are arranged in order from the upstream side. Below, the structure of each part arrange | positioned on the path | route of the introductory path | route 41 is demonstrated from the upstream to the downstream order.

  A pickup roller 30 and a separation roller 31 are disposed in the vicinity of the upstream end of the introduction path 41. The pickup roller 30 is configured to be rotatable around the rotation axis of the separation roller 31. When the ADF 24 is not operating, the pickup roller 30 is held on the upper side in FIG. On the other hand, when the original 100 is fed, the pickup roller 30 rotates downward and comes into contact with the end of the original 100 on the uppermost layer of the originals 100 set on the paper feed tray 52. When the pickup roller 30 rotates in this state, the uppermost document 100 on the paper feed tray 52 is conveyed to the separation roller 31.

  The document 100 sent to the separation roller 31 by the drive of the pickup roller 30 is separated one by one by the rotationally driven separation roller 31 and then conveyed to a registration roller 32 disposed on the downstream side.

  The registration roller 32, together with the opposing roller, temporarily stops and loosens the leading edge of the document 100 being conveyed, and conveys it downstream while removing the slackness after a predetermined time. Thereby, the skew of the document 100 is corrected. The document 100 that has passed the registration roller 32 is conveyed to a triple roller 33 disposed on the downstream side.

  The introduction path 41 from the separation roller 31 to the slightly upstream side of the triple roller 33 is a linear path.

  The triple roller 33 includes a driving roller 331 disposed at the center and driven rollers 332 and 333 disposed vertically so as to sandwich the driving roller 331 therebetween. The document 100 conveyed along the introduction path 41 passes between the driving roller 331 and the driven roller 332 disposed above the driving roller 331 and is conveyed obliquely to the lower left. The document 100 that has passed through the triple roller 33 is conveyed to a conveyance roller 34 disposed on the downstream side. The driven roller 333 disposed below the driving roller 331 has a rotation direction opposite to that of the driven roller 332, and conveys the document 100 passing between the driving roller 331 and the driven roller 333 to the right side. Can do.

  The conveyance roller 34 nips and rotates the original 100 together with the opposite roller, thereby conveying the original 100 to the lower right side (reading position side). Then, when the document 100 passes through the reading position, the image information on the first surface is read by the scanner unit 25. The conveyance roller 34 is configured to be able to switch the rotation direction. By rotating in the reverse direction, the document 100 can be conveyed to the upper left side (the triple roller 33 side).

  The introduction path 41 from the slightly upstream side of the triple roller 33 to the reading position is a path (introduction curve path 411 shown in FIG. 3) that swells to the left side (curves so as to be convex on the left side). .

  Next, the single-sided discharge path 43 will be described. A triple roller 35, a transport roller 36, a common roller 38, and a counter roller 39 are arranged in this order from the upstream side in the single-side discharge path 43. Below, the structure of each part arrange | positioned on the path | route of the single-sided discharge path | route 43 is demonstrated in order of the downstream from an upstream.

  There is a portion that branches vertically on the slightly downstream side of the reading position, and a triple roller 35 is disposed in the vicinity of the branched portion. The triple roller 35 includes a registration roller 351 (second feed roller) disposed in the center, and driven rollers 352 and 353 disposed vertically so as to sandwich the registration roller 351 therebetween. The document 100 whose image information has been read by the scanner unit 25 passes between the registration roller 351 and the driven roller 352 disposed above the registration roller 351 and is conveyed obliquely to the upper right. The document 100 that has passed through the triple roller 35 is conveyed to a common roller 38 that is positioned diagonally to the lower right of the conveyance roller 36 by a conveyance roller 36 disposed on the downstream side. The registration roller 351 has the same configuration as that of the registration roller 32. The registration roller 351 is inclined obliquely to the lower left side between the registration roller 351 and the driven roller 353 disposed below the registration roller 351. The line can be corrected.

  The common roller 38 nips and rotates the original 100 together with the opposing roller 39 disposed so as to face the original roller 100, thereby conveying the original 100 to the right side and discharging it to the paper discharge tray 53. As described above, image information on only one side of the original 100 set on the paper feed tray 52 is read. The common roller 38 is configured to be able to switch the rotation direction, and can rotate the document 100 to the left side (reading position side) by rotating in the opposite direction to when the document 100 is discharged.

  Next, a path for reading both sides of the document 100 will be described with reference to FIGS. 2 and 4 to 6. FIG. 4 is a schematic diagram for explaining the first inversion path 45. FIG. 5 is a schematic diagram for explaining the second inversion path 46. FIG. 6 is a schematic diagram for explaining the discharge path 47 for both sides.

  When reading both sides of the original 100, the original set on the paper feed tray 52 is conveyed to the reading position along the introduction path 41, as in the case of reading only one side of the original 100. Then, the image information on the first surface of the document 100 is read by the scanner unit 25. Further, the ADF 24 of the present embodiment is configured to be able to detect the length of the document 100 in the conveyance direction (document length), and operates a route guide or the like (not shown) based on the detected document length. Thus, the path through which the document 100 is conveyed next to the introduction path 41 can be switched.

  First, a path along which the document 100 is conveyed when the document length is short will be described. The document 100 in this case is configured to be conveyed along the first reversing path 45 shown in FIG. 4 after being conveyed along the introduction path 41 to the reading position. The first inversion path 45 includes, in order from the upstream side, a first pre-inversion path 451, a first inversion middle path 452, and a first post-inversion path 453.

  In the first pre-reversal path 451, a triple roller 35 and a transport roller 36 are arranged in order from the upstream side. Similar to the single-side discharge path 43, the document 100 conveyed along the first pre-reversal path 451 passes between the registration roller 351 and the driven roller 352 disposed thereabove and is conveyed diagonally to the upper right. Is done. Then, the document 100 is conveyed rightward by the conveyance roller 36 and conveyed to the first reverse path 452.

  The first inversion middle path 452 guides the document 100 obliquely downward to the right as in the case of the single-side discharge path 43 until halfway. However, after the branch point in the middle, the document 100 is guided so as to be conveyed obliquely downward to the left. This first inversion middle path 452 is a path that swells to the right (curves so as to be convex to the right). By being conveyed along this first reversing path 452, the front and back sides of the document 100 are reversed. That is, after the first surface facing the lower side (scanner unit 25 side) before being transported along the first reversing path 452 is transported along the first reversing path 452, Turn to face. Then, the document 100 conveyed along the first reversing path 452 is conveyed to the first reversing path 453.

  A conveyance roller 37 and a triple roller 35 are arranged in order from the upstream side in the first reverse path 453. The document 100 transported along the first reverse path 453 is transported to the left by the transport roller 37, and after the skew is corrected by the registration roller 351 of the triple roller 35, the document 100 passes through the reading position. In this way, the original 100 when the original length is short is reversed.

  Next, a path for reversing the document 100 when the document length is long will be described. Here, the case where the document length is long means that the document length is equal to the length of the first inversion path 45 or the document length is longer. If the document 100 having a long document length is conveyed along the first reversing path 45, the leading end of the document 100 after reversing the reading position with the trailing edge of the document 100 still remaining at the reading position. Since they are going to pass, the originals 100 overlap and cause a paper jam. Therefore, as shown in FIG. 5, the second inversion path 46 through which the document 100 passes when the document length is long is configured to be longer than the first inversion path 45.

  The second inversion path 46 includes a second pre-inversion path 461, a second inversion middle path 462, and a second post-inversion path 463. The second pre-inversion path 461 extends further to the right than the first pre-inversion path 451. Similar to the first inversion middle path 452, the second inversion middle path 462 has a path swelled to the right side (curved so as to be convex on the right side). The second post-inversion path 463 extends further to the right than the first post-inversion path 453.

  The second reverse path 463 passes through the common roller 38 when the document 100 is conveyed to the left side. However, as described above, the common roller 38 can be switched in the rotation direction, so that the common roller 38 is conveyed to the left side. can do. Thus, the common roller 38 has a function as a discharge roller and a function as a transport roller. In this way, the document 100 when the document length is long is reversed.

  Then, the original 100 which has been reversed by the first reversing path 45 or the second reversing path 46 and whose image information on the second surface has been read is conveyed to the duplex discharge path 47 shown in FIG.

  The document 100 conveyed along the duplex discharge path 47 passes through the reading position to the left side, and is then conveyed to the upper left side by the conveyance roller 34. Then, the document 100 passes between the driving roller 331 and the driven roller 333 disposed below the driving roller 331 and is conveyed rightward.

  Note that the duplex discharge path 47 from the reading position to the triple roller 33 is a path (a curved discharge path 471 shown in FIG. 6) that bulges to the left (curves so as to be convex on the left). Note that, in the original 100 conveyed along the introduction curved path 411 and the original 100 conveyed along the discharge curved path 471, the conveyance directions of the original 100 are opposite to each other. In this respect, the conveyance roller 34 of the present embodiment can switch the rotation direction, and further, the rotation directions of the driven roller 332 and the driven roller 333 are opposite to each other.

  Then, the document 100 conveyed along the duplex discharge path 47 and passed through the triple roller 33 is conveyed in the right direction, and after passing through the conveyance roller 36, is conveyed obliquely downward to the right. Then, similarly to the original 100 conveyed along the single-sided discharge path 43, it is discharged to the discharge tray 53 by the common roller 38 and the counter roller 39. Note that the double-side discharge path 47 from the branch point slightly downstream of the transport roller 36 to the branch point slightly upstream of the common roller 38 connects the second pre-reverse path 461 and the second post-reverse path 463 ( Connection path 472 shown in FIG. As described above, the image information on both sides of the original 100 set on the paper feed tray 52 is read.

  Next, a configuration for transmitting power to the conveyance roller 34 will be described. As described above, the transport roller 34 of the present embodiment rotates in one direction when the document 100 is transported along the introduction path 41, and the document 100 travels along the single-sided discharge path 43 or the double-sided discharge path 47. When it is conveyed, it is configured to rotate in the other direction.

  First, when the document 100 is transported along the introduction path 41, the power (rotational force) generated by the motor 90 shown in FIG. 7 is transmitted to the transport roller shaft 346 of the transport roller 34. A description will be given with reference to FIG. FIG. 7 is a front view showing a drive transmission path (first drive transmission path) 191 when the transport roller 34 is rotated in one direction. FIG. 10 is a block diagram showing an electrical configuration of the ADF 24.

  The motor 90 as a driving device is disposed on the back side of the apparatus (the back side of the paper surface in FIG. 7) with respect to the transport roller shaft 346. The power generated by the motor 90 is transmitted to an electromagnetic clutch (clutch) 91 disposed on the front side of the apparatus (the front side of the paper in FIG. 7) from the motor 90 via a transmission mechanism (not shown). The driving and stopping of the motor 90 is controlled by a control unit 58 for controlling the ADF 24 and the like as shown in FIG.

  As shown in FIG. 7, the electromagnetic clutch 91 includes an output gear 91a, and the output gear 91a meshes with a power branch gear (transmission gear, rotational force branch gear) 94. The electromagnetic clutch 91 is configured to be able to switch whether power generated by the motor 90 is transmitted to the output gear 91a or cut off (that is, whether power is transmitted to the power branch gear 94). This switching is controlled by the control unit 58 (FIG. 10).

  The power branching gear 94 is configured as a two-stage gear including two gears having a large diameter and a small diameter. The large-diameter gear meshes with the transmission gear 95 arranged on the left diagonally lower side, while the small-diameter gear meshes with the transmission gear 98 arranged on the diagonally lower right side. Thereby, rotation of the power branch gear 94 can be transmitted simultaneously in two directions.

  Then, the rotation of the power branch gear 94 is transmitted to the transmission gear 95, whereby the rotation is transmitted to the transport roller gear 345 through the transmission gear 96. Then, the conveyance roller shaft 346 is rotated by the rotation of the conveyance roller gear 345, whereby the conveyance roller 34 described above is rotated. As described above, the power of the motor 90 is transmitted to the transport roller 34 via the drive transmission path 191.

  On the other hand, the rotation of the power branch gear 94 is transmitted to the transmission gear 98, whereby the rotation is transmitted to the registration roller gear 355 that meshes with the transmission gear 98. The registration roller gear 355 is a gear for driving the rotation shaft of the registration roller 351 (FIG. 3 and the like). As described above, the power of the motor 90 is transmitted to the registration roller 351 via the drive transmission path (second drive transmission path) 192.

  Next, a configuration for switching the rotation direction of the transport roller 34 and a configuration for transmitting the power generated by the motor 90 after the switching to the transport roller shaft 346 will be described with reference to FIGS. 8 and 9. FIG. 8 is a front view showing a drive transmission path when the transport roller 34 is rotated in the other direction. FIG. 9 is a front view showing how the swing bracket 92 swings.

  In the present embodiment, the rotation number of the conveying roller 34 is switched by changing the number of gears to which power is transmitted by the gear number adjusting unit 99. The gear number adjusting unit 99 includes a swing bracket (oscillator) 92 and a solenoid (oscillator drive unit) 93.

  The swing bracket 92 has a structure in which two plate-like members are arranged side by side, and the power branch gear 94 and the transmission gears 95 to 97 are attached to the swing bracket 92. The power branch gear 94 is attached to the swing bracket 92 via a branch gear shaft 941. A bearing or the like is attached to the branch gear shaft 941 so that the power branch gear 94 can freely rotate relative to the swing bracket 92.

  A solenoid 93 is connected to the upper end of the swing bracket 92. The swing bracket 92 is configured to be rotatable about the branch gear shaft 941 as a rotation axis in accordance with the displacement of the movable iron core 931 of the solenoid 93 (see FIG. 9). In FIG. 9, the position of the swing bracket 92 when the transport roller 34 is rotated in one direction is indicated by a solid line, and the position of the swing bracket 92 when the transport roller 34 is rotated in the other direction is indicated by a two-dot chain line. . In addition, the timing which displaces the movable iron core 931 of this solenoid 93 is controlled by the control part 58 (FIG. 10).

  The transmission gears 95, 96, and 97 are disposed so as to be rotatable relative to the swing bracket 92. Further, the positions of the transmission gears 95, 96, and 97 are changed in accordance with the rotation of the swing bracket 92.

  Then, the transmission gears 95, 96, and 97 move from the position shown in FIG. 7 to the position shown in FIG. 8, so that the power generated by the motor 90 is transmitted along the drive transmission path (first drive transmission path) 193. Will come to be. Further, in the drive transmission path 193 in FIG. 8, power is transmitted through one more gear (transmission gear 97) than in the drive transmission path 191 formed at the time of FIG. The rotation direction of 34 is the reverse direction. As described above, the control unit 58 controls the solenoid 93 to swing the swing bracket 92, whereby the rotation direction of the transport roller 34 can be switched.

  Further, the swing bracket 92 has a shape in which a lower end portion is recessed, and the swing bracket 92 is positioned by using restriction surfaces 921 and 922 formed in this portion. Specifically, when the swing bracket 92 rotates from the position shown in FIG. 7 to the position shown in FIG. 8, a restriction surface 922, a metal bush 347 attached to the conveyance roller shaft 346 so as to be relatively rotatable, Positions by touching. On the other hand, when the swing bracket 92 rotates from the position shown in FIG. 8 to the position shown in FIG. 7, positioning is performed by the contact between the restriction surface 921 and the metal bush 347. By this positioning, the distance between the shafts of the transmission gear 96 (transmission gear 97) and the conveying roller gear 345 can be appropriately maintained, and smooth engagement between the gears can be realized. Further, since the regulating surfaces 921 and 922 are disposed near the transmission gears 96 and 97, the gear positioning accuracy is particularly good.

  It is desirable to operate the gear number adjusting unit 99 as follows. That is, the control unit 58 controls the electromagnetic clutch 91 to be in a disconnected state before swinging the swing bracket 92 so that the rotation of the motor 90 is not transmitted to the power branch gear 94. Then, the control unit 58 controls the solenoid 93 to move the swing bracket 92 from the position shown in FIG. 7 to the position shown in FIG. Thereafter, the control unit 58 controls the electromagnetic clutch 91 to be in a connected state, and transmits the rotation of the motor 90 to the power branch gear 94. As a result, no rotational force is transmitted to the transmission gear 96 (transmission gear 97) at the time of switching between meshing / unmeshing with the transport roller gear 345, so that the gear teeth are prevented from being damaged at the meshing portion. be able to.

  As described above, the ADF 24 according to the present embodiment includes the document conveyance path 40, the conveyance roller 34, the motor 90, the power branch gear 94, the transmission gears 95 to 97, the electromagnetic clutch 91, and the number of gears adjustment. Unit 99 and a control unit 58. The document conveyance path 40 is for conveying the document 100. The conveyance roller 34 is disposed in the document conveyance path 40 and can be rotated in both directions. The motor 90 generates a rotational force that drives the transport roller 34. The transmission gears 95 to 97 transmit the rotational force to the transport roller 34. The electromagnetic clutch 91 can switch whether this rotational force is transmitted to the power branch gear 94 or cut off. The gear number adjusting unit 99 can change the number of transmission gears through which this rotational force is transmitted to the conveying roller 34. The control unit 58 controls the electromagnetic clutch 91 and the gear number adjusting unit 99. The controller 58 performs processing including a first step, a second step, and a third step when switching the rotation direction of the rotating transport roller 34. In the first step, the rotational force is interrupted by controlling the electromagnetic clutch 91. In the second step, by controlling the gear number adjusting unit 99, the number of transmission gears through which the rotational force passes is increased or decreased by one. In the third step, the rotational force in the same direction as in the first step is transmitted by controlling the electromagnetic clutch 91.

  As a result, the rotation direction of the transport roller 34 can be switched without switching the rotation direction of the motor only by providing one electromagnetic clutch 91, so that the ADF 24 can be made compact and low cost. Further, when the number of transmission gears through which the rotational force of the motor 90 passes is changed, the rotational force is blocked by the electromagnetic clutch 91, so that the teeth of the transmission gear can be prevented from being damaged.

  Further, in the ADF 24 of the present embodiment, the gear number adjusting unit 99 includes a swing bracket 92 and a solenoid 93. The swing bracket 92 is attached so that the transmission gears 95 to 97 can rotate relative to each other. The solenoid 93 switches the number of transmission gears through which the rotational force passes by swinging the swing bracket 92.

  Thereby, the rotation direction of the conveyance roller 34 can be switched with a simple configuration.

  Further, in the ADF 24 of the present embodiment, the swing bracket 92 is positioned by bringing the metal bush 347 into contact with the regulation surfaces 921 and 922 of the swing bracket 92.

  Thereby, since the swing bracket 92 can be positioned with a simple configuration, the ADF 24 can be made compact and inexpensive.

  Further, in the ADF 24 of the present embodiment, the swing bracket 92 can switch the number of transmission gears through which the rotational force passes by rotating around the branch gear shaft 941. The branch gear shaft 941 is disposed at a branch point between a drive transmission path 191 that transmits rotation from the motor 90 to the conveyance roller 34 and a drive transmission path 193 that transmits rotation from the motor 90 to the registration roller gear 355.

  As a result, the position of the power branch gear 94 does not change even if the swing bracket 92 is swung. The rotation is transmitted. Therefore, even when the rotation direction of the transport roller 34 is switched, the registration roller 351 can be continuously rotated in the same direction. In addition, since the motor 90 and the electromagnetic clutch 91 can be shared by the transport roller 34 and the registration roller 351, the number of parts can be reduced and the ADF 24 can be reduced in cost.

  The preferred embodiment of the present invention has been described above, but the above configuration can be modified as follows, for example.

  Instead of the scanner unit 25 of the reduction optical system used in the above embodiment, a configuration using a contact image sensor or the like can be used.

  The gear number adjusting unit 99 is configured to switch the number of gears through which the rotational force passes as the swing bracket 92 rotates. ) To switch the number of gears through which the rotational force passes. As described above, various methods can be used as a method of switching the number of gears through which the rotational force passes.

  In the above embodiment, the transmission gears 96 and 97 that rotate together with the swing bracket 92 are configured to transmit the rotation directly to the transport roller gear 345. Instead, a transmission gear that swings together with the swing bracket 92 may transmit rotation to another transmission gear, and the transmission gear may transmit rotation to the transport roller gear 345. In this case, a bearing or the like attached to the gear shaft of the transmission gear can be used as a member for positioning the swing bracket 92.

  In the above-described embodiment, the example in which the present invention is applied to the conveyance roller 34 has been described. However, since the rotation direction of the common roller 38 can also be switched, the present invention can also be applied to the common roller 38.

  In the above-described embodiment, an example in which the present invention is applied to the ADF 24 that can read both sides by a path for reversing the front and back sides of the document has been described. The present invention can also be applied to a roller. In addition to the ADF, the configuration of the present invention can be applied to a wide range of applications as long as the sheet-like material is separated and conveyed one by one. For example, the configuration of the present invention can be used for a switchback roller of a multifunction machine capable of printing both sides.

  In the above-described embodiment, the image scanner device 11 is provided as a part of the multifunction device 1. However, instead of this configuration, the image scanner device 11 can be configured as a single image scanner device.

1 MFP 11 Image Scanner Device (Document Reading Device)
24 ADF (sheet material feeder)
34 Conveyance roller (feed roller)
40 Document transport path (sheet-shaped material transport path)
45, 46, 47, 48 Transmission gear 58 Control unit 90 Motor (drive device)
91 Electromagnetic clutch (clutch)
92 Oscillation bracket (Oscillator)
93 Solenoid (oscillator drive)
94 Power branch gear 99 Gear number adjustment section

Claims (6)

A sheet material conveying path for conveying the sheet material;
A feed roller disposed in the sheet-like material conveyance path and rotatable in both directions;
A driving device for generating a rotational force for driving the feed roller;
A plurality of transmission gears for transmitting the rotational force to the feed roller;
A clutch capable of switching between transmitting or blocking the rotational force to the transmission gear;
A gear number adjusting unit capable of changing the number of transmission gears through which the rotational force is transmitted to the feed roller;
A control unit for controlling the clutch and the gear number adjusting unit;
With
When the control unit switches the rotation direction of the rotating feed roller,
A first step of cutting off the rotational force by controlling the clutch;
A second step of changing the number of transmission gears through which the rotational force passes from odd to even or even to odd by controlling the gear number adjusting unit;
A third step of transmitting the rotational force in the same direction as the first step by controlling the clutch;
A sheet-like material feeding device characterized by performing processing including: The sheet-like material feeding device according to claim 1,
The gear number adjusting unit is
An oscillating body to which the transmission gear is mounted so as to be relatively rotatable;
An oscillating body drive unit that switches the number of the transmission gears through which the rotational force passes by oscillating the oscillating body;
A sheet-like material feeding device comprising: The sheet-like material feeding device according to claim 2,
The swinging body is positioned by bringing the swinging body into contact with a member positioned at the center of the feed roller or a member positioned at the center of the transmission gear that is not connected to the swinging body. A sheet-like material feeder. The sheet-like material feeding device according to claim 2 or 3,
A second feed roller;
The oscillating body is capable of switching the number of the transmission gears that pass through by rotating about the oscillating shaft,
The swing shaft includes a first drive transmission path for transmitting the rotational force from the drive device to the feed roller, a second drive transmission path for transmitting the rotational force from the drive device to the second feed roller, At the bifurcation point of
The sheet-like material feeding device according to claim 1, wherein the transmission gear includes a rotational force branching gear arranged so that a rotation shaft coincides with the swing shaft. The sheet-like material feeding device according to claim 4,
The sheet-like material feeding device, wherein the second feeding roller is a registration roller that corrects the skew of the sheet-like material. A sheet-like material feeding device according to any one of claims 1 to 5;
A reading unit for reading image information of a document as a sheet material;
An original reading apparatus comprising:

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