JP2016185835A - Recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording device being capable of securing satisfactory handleability while reliably performing skew correction.SOLUTION: A printer 1 comprises: a manual feeding tray 41 placing a sheet; a feeding roller 15 feeding the sheet from the manual feeding tray by normal rotation; a separation roller 16 nipping and separating the sheet between the feeding roller 15 and the separation roller 16; and a register roller pair 17 being positioned closer to a downstream side than the feeding roller 15 and causing a leading end of the sheet to abut thereagainst. The printer 1 further comprises: a one-way clutch realizing a one-way function allowing the normal rotation of the feeding roller 15 and regulating reverse rotation of the feeding roller 15; and switching means switching on and off of the one-way function of the one-way clutch.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a recording apparatus that performs recording on a medium.

  2. Description of the Related Art Conventionally, in a recording apparatus typified by an ink jet printer or the like, a technique for correcting skew (skew) by abutting a sheet fed from a sheet loading unit such as a sheet feeding tray by a feeding roller to a registration roller has been used. Yes. That is, the front end of the paper is abutted against the registration roller, and the paper is bent between the registration roller and the feeding roller. By this bending, the leading edge of the sheet follows the registration roller, and the skew is corrected (see Patent Documents 1 and 2).

JP 2003-155148 A JP 2013-11812 A

  When a thick sheet is abutted against the registration roller to form a bend, it is difficult to maintain the bend due to the high rigidity, and the feed roller may reverse. In the image forming apparatus described in Patent Document 1, it is a problem that the paper position varies due to the reverse rotation of the feeding roller. In the case of a thick paper such as a postcard, the leading edge of the paper is brought into contact with the registration roller. Is controlled so as to slightly bite into the nip of the registration roller. However, no special measures are taken with respect to the reverse rotation of the feeding roller, and there is a case where sufficient skew correction cannot be performed.

  In the image reading apparatus described in Patent Document 2, a one-way clutch is applied to the paper feed roller. By providing such a one-way clutch, it is possible to prevent reverse rotation of the paper feed roller.

In addition, when the speed of the transport roller located downstream of the feed roller is high, when the paper straddles the transport roller and the paper feed roller, a back tension is applied to the paper at the feed roller. In order to avoid this, a one-way clutch may be provided on the paper feed roller.
However, in this configuration, since the reverse rotation of the paper feed roller is not allowed, it is difficult to pull out the paper when a paper jam occurs, resulting in a problem that handling properties are deteriorated.

  Therefore, the present invention has been made in view of such a situation, and an object of the present invention is to provide a recording apparatus that can ensure good handling of paper even when a one-way clutch is provided on a paper feed roller. Is to provide.

  In order to solve the above problems, a recording apparatus according to a first aspect of the present invention includes a medium placement unit for placing a medium, a feeding roller for feeding the medium from the medium placement unit by forward rotation, A separation unit that nips and separates the medium from the feeding roller, a recording head that is positioned downstream of the separation unit in the medium conveyance direction, and that records on the medium, and is driven by the rotation shaft of the feeding roller A motor that applies torque, a one-way clutch that realizes a one-way function that allows forward rotation of the feeding roller and restricts reverse rotation of the feeding roller, a switching unit that switches on / off of the one-way function, and a medium jam A jam detecting means for detecting, and performing on / off switching of the one-way function by the switching means according to a detection result of the jam detecting means. .

  According to this aspect, since the one-way function is switched on and off by the switching unit according to the detection result of the jam detection unit, the one-way function is turned on / off according to the jam state. The handling property of the medium can be ensured.

  According to a second aspect of the present invention, in the first aspect, the detection unit configured to detect the passage of the medium that constitutes the jam detection unit between the feeding roller and the recording head in the medium conveyance path. And the switching means turns off the one-way function when a medium jam occurs in a state where the leading edge of the medium is upstream of the detection means.

  According to this aspect, when a medium jam occurs in the state where the leading edge of the medium is upstream of the detection means provided between the feeding roller and the recording head, the switching means performs the one-way function. Since it is turned off, the feed roller is allowed to reverse, and the jammed medium can be easily removed.

  According to a third aspect of the present invention, in the second aspect, when the detection unit detects a jam of the medium after detecting the passage of the front end of the medium, the switching unit maintains the one-way function on. And

  When the detection unit detects a jam of the medium after detecting the passage of the front end of the medium, there is a high possibility that recording has been performed on the medium. In this case, if the jammed medium is pulled out carelessly, the inside of the apparatus may be soiled with undried liquid (for example, ink). However, according to this aspect, when the detection unit detects a jam of the medium after detecting the passage of the leading end of the medium, the switching unit maintains the one-way function on, so that the medium on which the recording is performed is inadvertent. It can be avoided that the inside of the apparatus is soiled.

According to a fourth aspect of the present invention, in any one of the first to third aspects, the switching means holds the one-way clutch and includes a rotating body having a plurality of tooth portions along an outer periphery, and the tooth portion. It is possible to switch between a state of engaging with the tooth part and a state of separating from the tooth part, and by engaging with the tooth part, the rotation of the rotating body is constrained to turn on the one-way function and separate from the tooth part. And an engaging member that allows rotation of the rotating body and turns off the one-way function.
According to this aspect, the switching means can be configured at a low cost with a simple structure.

According to a fifth aspect of the present invention, in the fourth aspect, the tooth portion is formed obliquely in a direction that opposes the reverse rotation of the feeding roller.
According to this aspect, since the tooth portion is formed obliquely in a direction that opposes the reverse rotation of the feeding roller, the on state of the one-way function can be reliably maintained.

1 is an external perspective view of an inkjet printer according to the present invention. FIG. 3 is a side cross-sectional view illustrating a paper conveyance path of the ink jet printer according to the present invention. FIG. 3 is a side cross-sectional view illustrating a paper conveyance path of the ink jet printer according to the present invention. FIG. 3 is a side sectional view showing a paper feeding path of the ink jet printer according to the present invention. FIG. 3 is a side sectional view showing a paper feeding path of the ink jet printer according to the present invention. FIG. 3 is a side sectional view showing a paper feeding path of the ink jet printer according to the present invention. The perspective view of a manual feed tray and a feeding roller drive mechanism. Sectional drawing of a feeding roller drive mechanism. The front view of the switching means which switches on / off of a one-way function. The front view of the switching means which switches on / off of a one-way function. The perspective view of a registration roller pair drive mechanism. The timing chart which shows the control content which a control part performs. The flowchart which shows control of the one-way clutch at the time of paper jam generation | occurrence | production.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings. However, the invention is not limited to the embodiment described below, and various modifications are possible within the scope of the invention described in the claims. Assuming that these are also included in the scope of the present invention, one embodiment of the present invention will be described below.

  FIG. 1 is an external perspective view of an ink jet printer (hereinafter referred to as “printer”) 1 as an embodiment of a “recording apparatus” according to the present invention, and FIGS. It is. 7 is a perspective view of the manual feed tray 41 and the feed roller drive mechanism, FIG. 8 is a cross-sectional view of the feed roller drive mechanism, and FIGS. 9 and 10 are front views of the switching means 53 for switching on / off of the one-way function. 11 is a perspective view of the registration roller pair drive mechanism, and FIG. 12 is a timing chart showing the contents of control performed by the control unit 9. FIG. 13 is a flowchart showing the control of the one-way clutch 49 when a paper jam occurs.

Hereinafter, an overall configuration of the printer 1 that performs ink jet recording on a recording sheet as an example of a medium will be described with reference to FIGS. 1 and 2.
In FIG. 1, an inkjet printer 1 includes a scanner device 3 above an apparatus main body 2A that records on recording paper, and additional units 2B and 2C below the apparatus main body 2A. The apparatus main body 2A includes a paper cassette 10A, the expansion unit 2B includes a paper cassette 10B, and the expansion unit 2C includes a paper cassette 10C. These extension units 2B and 2C are optional units for increasing the number of sheets accommodated, and are optionally attached to the apparatus main body 2A.

  Reference numeral 5 denotes an operation unit that performs various operations of the printer 1, and reference numeral 4 denotes a tray that receives the recording paper that is recorded and discharged, and more specifically, the recording surface on which recording has been performed most recently. 2 is a face-down paper discharge tray for receiving recording paper discharged with the face down. Reference numeral 35 denotes a feeding unit, which can be opened and closed with respect to the apparatus main body 2A by rotating about a rotation fulcrum (not shown). Reference numeral 6 denotes an open / close cover constituting the feeding unit 35, which can swing around a swing shaft 6a (FIG. 2). Reference numeral 41 (FIG. 2) is a manual feed tray that swings together with the opening / closing cover 6, and can be opened and closed by rotating around a swinging shaft 41 a. Note that the manual feed tray 41 shown in FIG. 2 is in the storage position, and is opened clockwise from the state of FIG. 2 and can be manually fed in a state of facing obliquely upward (see FIG. 4 and subsequent drawings).

  In the printer 1, the side where the operation unit 5 is disposed is the front side of the apparatus, and the side where the opening / closing cover 6 is provided is the right side of the apparatus. That is, feeding, transporting, and discharging of paper in the printer 1 are performed along the left-right direction of the apparatus.

  Next, the paper transport path in the printer 1 will be outlined with reference to FIG. The printer 1 has a feeding path from the paper cassette 10A (see the cassette feeding locus S1), a feeding path from the additional cassettes 10B and 10C (not shown in FIG. 2) (see the additional cassette feeding locus S2), and a medium. These three paper feeding paths, that is, a feeding path (see the manual feeding path S3) from the manual feed tray 41 constituting the “medium loading section” on which the paper is placed.

  In addition, the printer 1 discharges face-up discharge with the recording surface most recently recorded facing upward (see face-up discharge locus T1) and face-down discharge discharging with the recording surface most recently recorded facing down. (Refer to the face-down discharge locus T2).

  In FIG. 2, reference numeral 7 denotes a face-up discharge tray that receives paper that is discharged face-up. The face-up paper discharge tray 7 can take the storage state shown in FIG. 2 and the open state (not shown) by rotating about the rotation shaft 7a.

  Then, the printer 1 has a recording transport path R1 as a “first transport path”, a switchback path R2 as a “second transport path”, a reverse path R3 as a “third transport path”, and a “fourth transport path”. These five sheet transport paths, namely, a face-down discharge path R4 and a face-up discharge path R5 are provided.

  In FIG. 2, reference numeral 33 denotes a flap (path switching member) driven by a drive source (not shown), and switches between a state indicated by a solid line and reference numeral 33 in FIG. 2 and a state indicated by a virtual line and reference numeral 33 ′. .

  When the flap 33 is in the state indicated by the solid line in FIG. 2, the recording sheet is guided to the face-down discharge path R4 and discharged face-down as indicated by the face-down discharge locus T2. When the flap 33 is in the state of the imaginary line and reference numeral 33 ′ in FIG. 2, the recording sheet is guided to the face-up discharge path R <b> 5 and discharged face-up as indicated by the face-up discharge path T <b> 1.

In FIG. 2, reference numeral 9 denotes a control unit that performs various controls. The control unit 9 includes various rollers driven by an inkjet recording head 8 and a motor (not shown) described below, in particular various rollers such as a feeding roller 15, a registration roller pair 17, and a conveyance roller pair 18, and each path switching member. (Flap) is controlled, and necessary control is performed based on detection states of various sensors (for example, sensors that detect passage of a recording sheet). Note that the control unit 9 is conceptually shown in FIG. 2, and actually includes a circuit board provided at a predetermined position in the apparatus main body 2A.
Hereinafter, the sheet feeding path to the registration roller pair 17 will be described with reference to FIG.

  A paper cassette 10A detachably provided in the apparatus main body 2A includes a hopper 11, and the recording paper P accommodated in the paper cassette 10A is moved by a motor (not shown) by swinging the hopper 11 about a shaft 11a. To and away from the feeding roller 12 that is driven to rotate.

The recording paper fed from the paper cassette 10A by the feed roller 12 is separated (prevents double feed) by passing through the nip position by the separation roller pair 13, and receives the feed force from the transport roller pair 14 to receive the transport roller pair. 17 is reached. The extension units 2B and 2C (FIG. 1) located under the apparatus main body 2A are similarly provided with a feeding roller 12 and a separation roller 13, and the recording paper P sent out from each paper cassette is a transport roller shown in FIG. Receiving the feeding force from the pair 14, it reaches the registration roller pair 17.
The recording paper P supplied via the manual feed tray 41 receives the feeding force from the feeding roller 15 and reaches the registration roller pair 17. It should be noted that no conveying means such as a roller pair for applying a conveying force to the paper is interposed between the feeding roller 15 and the registration roller pair 17.

  Hereinafter, the sheet conveyance path downstream of the registration roller pair 17 will be described with reference to FIG. In FIG. 3, the description will be made on the assumption that the recording sheet is discharged face-down via the face-down discharge path R4.

  First, the rollers provided in each paper transport path will be described. In FIG. 3, reference numeral 17 denotes a registration roller pair, and reference numerals 18 to 29 denote conveyance roller pairs that all convey recording paper. In particular, one roller of the conveyance roller pairs 19 to 28 is indicated by reference numeral F, and the other side. These rollers are indicated by the symbol G. The roller F is a driving roller driven by a motor (not shown), and as an example, is a rubber roller provided with a plurality of appropriate intervals in the paper width direction.

The roller G is a driven roller that rotates in contact with the recording paper, and is provided in a pair with the roller F at an appropriate interval in the paper width direction. The roller G is a serrated roller having a plurality of teeth on the outer periphery, and suppresses white leakage and transfer of ink on the recorded surface by making point contact with the recording surface.
The driven roller G is provided at an appropriate position on the paper conveyance path, in addition to constituting each conveyance roller pair, and particularly provided on the side in contact with the already recorded surface.

  On the other hand, the resist roller pair 17 and the transport roller pairs 18 and 29 have different configurations from the transport roller pairs 19 to 28. Specifically, the registration roller pair 17 includes a drive roller 17a that is rotationally driven and a driven roller 17b that can be driven and rotated, and the driven roller 17b is a resin roller having a smooth outer peripheral surface.

  Similarly, the transport roller pair 18 includes a driving roller 18a that is rotationally driven and a driven roller 18b that can be driven and rotated. The driven roller 18b is a resin roller having a smooth outer peripheral surface. Similarly, the transport roller pair 29 includes a drive roller 29a that is rotationally driven and a driven roller 29b that can be driven and rotated. Of these, the driven roller 29b is a resin roller having a smooth outer peripheral surface.

  Between the rollers described above, the recording paper is guided by the upper and lower guide members. In FIGS. 2 and 3, in order to avoid complication of the drawings, the guide members are not denoted by reference numerals, but the thick lines connecting the rollers indicate the guide members. The guide member between the registration roller pair 17 and the conveyance roller pair 18 will be described with reference to FIG.

  Next, the recording transport path R1 as the first transport path passes under the ink jet recording head 8 as a recording unit that performs recording on the recording paper, and extends upstream and downstream thereof. In this embodiment, for the sake of convenience, the recording conveyance path R1 is generally from the position M1 to the position M2 in FIG. In the recording conveyance path R1, the recording paper receives a feeding force from the registration roller pair 17 and the conveyance roller pairs 18 and 19.

  In the present embodiment, the ink jet recording head 8 is a recording head provided such that the nozzles for ejecting ink cover the entire region in the paper width direction, and recording is performed over the entire paper width without moving in the paper width direction. The recording head is configured to be capable of recording.

  The switchback path R2 as the second transport path is a transport path that is connected to the recording transport path R1, and after the recording paper that has passed under the ink jet recording head 8 is sent (left direction in FIG. 3), the switchback path R2 is switched back. Thus, it is a path for conveying in the direction opposite to the feeding direction (right direction in FIG. 3), and is located inside the curve with respect to the face-down discharge path R4 described later. In this embodiment, for the sake of convenience, the switchback path R2 is generally on the left side from the position M3 in FIG. In the switchback path R2, the recording sheet receives a feeding force from the pair of conveying rollers 26.

  The reverse path R3 as the third transport path is a transport path connected to the switchback path R2, and bypasses the upper side of the ink jet recording head 8 for the recording paper transported in the reverse direction (right direction in FIG. 3). And are joined at the upstream position of the inkjet recording head 8 in the recording conveyance path R1 (in this embodiment, the upstream position of the registration roller pair 17). In this embodiment, for the sake of convenience, the inversion path R3 is generally a path from the position M3 to the position M4 in FIG. In the reversing path R3, the recording sheet receives a feeding force from the conveying roller pair 27, 28, 29.

  The face-down discharge path R4 as the fourth transport path is a transport path that is connected to the recording transport path R1, and the recording paper that passes under the ink jet recording head 8 faces the ink jet recording head 8 inside. It is a path for curving, reversing and discharging. In the present embodiment, for the sake of convenience, the face-down discharge path R4 is generally on the left side from the position M2 in FIG. In the face-down discharge path R4, the recording sheet receives a feeding force from the conveyance roller pair 20, 21, 22, 23, 24, 25.

In addition, the connection part of each conveyance path | route is provided with the 1st flap 31 and the 2nd flap 32 as a path | route switching member which switches a conveyance path | route. The first flap 31 can swing about a swing fulcrum 31a by receiving a driving force from a driving means (not shown). Further, the second flap 32 is provided so as to be engageable with the first flap 31 via an engaging portion (not shown), and swings around the swing fulcrum 32 a according to the swing of the first flap 31.
These flaps set the path of the paper.

  In FIG. 2, reference numeral 34 denotes a transport unit that can be mounted on and pulled out from the printer body. By pulling out the transport unit 34 from the printer main body, the position near the downstream side of the transport roller pair 19 can be exposed, and the jammed paper can be easily removed.

Next, sheet feeding in the manual feeding path S3 will be described with reference to FIG.
In FIG. 4, reference numeral 40 denotes a lifter, which constitutes a “medium placement unit” on which a medium is placed together with the manual feed tray 41. The lifter 40 is provided so as to be lifted and lowered by a power source (not shown) under the control of the control unit 9 (FIG. 2). For example, FIG. 4 shows a lowered state and FIG. 5 shows a raised state. In the state where the lifter 40 is lowered as shown in FIG. 4, the upper surface of the lifter 40 is substantially at the same height as the open manual feed tray 41, and forms a substantially flat surface (paper placement surface) before feeding. Support the paper. Reference numeral 42 denotes an edge guide for regulating the edge of the paper placed on the manual feed tray 41.

  Next, reference numeral 36 denotes a friction member provided on the lifter 40. In the state where the lifter 40 is raised, the sheet is nipped by the feed roller 15 and the lifter 40 as shown in FIG. 5, and the uppermost sheet (indicated by a broken line and symbol P <b> 1) in contact with the feed roller 15 is sent out. It is. At this time, the friction member 36 functions to hold the next and subsequent sheets (indicated by a two-dot chain line) from being sent out downstream. The friction member 36 constitutes a facing portion where the lifter 40 and the feeding roller 15 face each other. Further, in the present embodiment, the feeding roller 15 is a normal circular roller, and can contact the paper all around.

Next, the code | symbol 16 is a separation roller provided in the state to which predetermined | prescribed rotational resistance was provided. The separation roller 16 is a roller having an outer peripheral surface made of a high-friction material (for example, rubber), and is positioned downstream of the friction member 36 in the paper conveyance direction, and separates the paper by nipping it with the feeding roller 15. Parts. For example, the separation roller 16 is in contact with the paper P1 to be fed, and is driven to rotate as the paper P1 is conveyed.
The configurations of the manual feed tray 41, the lifter 40, the feeding roller 15, the separation roller 16, and the like are also shown in FIG.

Reference numerals 37, 38, and 39 denote sensors as detection means for detecting passage of the leading edge or trailing edge of the sheet. The sensors 37, 38, and 39 are optical sensors including, for example, a light emitting unit and a light receiving unit, and the control unit 9 detects the passage of the front end or the rear end of the paper by using a change in the light reception intensity of the light receiving unit. The sensor denoted by reference numeral 37 is hereinafter referred to as “rear end sensor 37”, similarly, the sensor denoted by reference numeral 38 is referred to as “pre-registration sensor 38”, and the sensor denoted by reference numeral 39 is referred to as “pre-printing sensor 39”. I will call it.
As will be described later, the sensors 38 and 39 as detection means also function as jam detection means for detecting a paper jam.

  However, if the ink jet recording head 8 performs recording with movement in the paper width direction, unlike the present embodiment, depending on the form of the paper jam, the carriage provided with the recording head may be used for the paper. In some cases, jams can be detected. Specifically, when the carriage is driven, if the carriage is blocked by the jammed paper, the drive current value of the motor that is the drive source increases. Thereby, a paper jam may be detected.

Next, a driving mechanism for the feeding roller 15 will be described. 7 and 8 show a driving mechanism for driving the feeding roller 15. Reference numeral 44 denotes a motor, and power is transmitted from the motor 44 to the clutch 47 through the gear group 45. In FIG. 8, the motor 44 and a part of the gear group 45 are not shown.
The clutch 47 switches between a state where the power of the motor 44 is transmitted to the rotating shaft 15 a of the feeding roller 15 and a state where it is not transmitted under the control of the control unit 9.

  The clutch 47 includes a transmission gear 47a and a transmitted portion 47b. The transmission gear 47a is not connected to the rotation shaft 15a of the feeding roller 15, and is rotatable relative to the rotation shaft 15a. The transmission gear 47 a meshes with a gear 45 a that constitutes the gear group 45. In FIG. 8, reference numeral 45b denotes a gear that transmits driving force to the gear 45a. That is, when the motor 44 rotates, the transmission gear 47a of the clutch 47 always rotates.

  The transmitted portion 47b is connected to the rotating shaft 15a of the feeding roller 15, and is provided so as to be able to switch between a state of being connected to the transmission gear 47a and a state of being disconnected. When the transmitted portion 47b is connected to the transmission gear 47a, the driving force of the motor 44 is transmitted to the rotating shaft 15a of the feeding roller 15.

Subsequently, reference numeral 49 indicates a one-way clutch. The one-way clutch 49 allows rotation of the feed roller 15 when the feed roller 15 rotates in the normal rotation direction, which is the rotation direction when the paper is sent out, and restricts rotation of the feed roller 15 in the reverse direction. Realize the one-way function.
The one-way clutch 49 includes a clutch part 50 and a gear part 51. In a state where the gear portion 51 is restrained from rotating, the clutch portion 50 realizes the one-way function. In a state where the gear portion 51 is allowed to rotate, the one-way function is turned off.

  More specifically, reference numeral 53 indicates switching means for switching on / off of the one-way function. The switching means 53 is also shown in FIGS. The switching means 53 includes a lever 55 as an “engagement member” and a solenoid 54. The lever 55 is provided so as to be swingable about a swing shaft 55 a, and by swinging, the locking portion 55 b formed at the tip is engaged with the gear portion 51 (tooth portion 51 a) of the one-way clutch 49. The state of engagement (meshing) (FIG. 10) and the state of separation from the gear portion 51 (tooth portion 51a) (FIG. 9) are switched.

  The solenoid 54 is engaged with the upper portion of the lever 55 and swings the lever 55 by a linear stroke under the control of the control unit 9. The spring 56 having one end hooked on a spring hooking portion 55c formed on the upper portion of the lever 55 is a direction in which the locking portion 55b of the lever 55 is engaged (engaged) with the gear portion 51 (tooth portion 51a) of the one-way clutch 49. This is a coil spring as a biasing means for biasing the lever 55.

  With the above configuration, in the state where the locking portion 55b of the lever 55 is engaged (engaged) with the gear portion 51 (tooth portion 51a) of the one-way clutch 49 (FIG. 10), the rotation of the gear portion 51 of the one-way clutch 49 is restricted. Then, the one-way function of the one-way clutch 49 (clutch unit 50) is turned on. Conversely, in a state where the locking portion 55b of the lever 55 is separated from the gear portion 51 (tooth portion 51a) of the one-way clutch 49 (FIG. 9), the gear portion 51 of the one-way clutch 49 is allowed to rotate and the one-way clutch 49 ( The one-way function of the clutch part 50) is turned off.

  In addition, the tooth | gear part 51a with which the gear part 51 is provided is formed diagonally as shown in the enlarged view enclosed with the dashed-dotted line in FIG. This oblique direction is a direction that opposes the reverse rotation of the feeding roller 15 (the rotation of the gear portion 51 in the counterclockwise direction in FIG. 10). As a result, the ON state of the one-way function can be reliably maintained (the engagement between the tooth portion 51a and the locking portion 55b can be reliably maintained), and eventually the sheet is bent between the feeding roller 15 and the registration roller pair 17. (Described later) can be formed reliably.

Next, a drive mechanism for driving the registration roller pair 17 will be described with reference to FIG. Reference numeral 60 denotes a motor, and power is transmitted from the motor 60 to the clutch 58 via the gear group 61.
Under the control of the control unit 9, the clutch 58 switches between a state in which the power of the motor 60 is transmitted to the rotating shaft 17 c of the drive roller pair 17 a constituting the registration roller pair 17 and a state in which the power is not transmitted. The clutch 58 has the same configuration as the clutch 47 already described.

  Reference numeral 59 denotes brake means for applying a braking force to the rotating shaft 17c under the control of the control unit 9. Although the detailed configuration of the brake means 59 is omitted, the basic configuration is the same as that of the clutch 47 already described.

In the above configuration, the control unit 9 performs the control shown in FIG. 12 as an example during recording execution. In FIG. 12, the horizontal axis indicates the passage of time, and the vertical axis is as follows.
“Recording execution” indicates a recording execution period, ON indicates a recording execution period, and OFF indicates a non-recording period.
“Pre-printing sensor” indicates the pre-printing sensor 39, where ON indicates paper detection and OFF indicates paper non-detection.

“Registration clutch” indicates the clutch 58, ON indicates a drive transmission state, and OFF indicates a non-transmission state. “Pre-registration sensor” indicates the pre-registration sensor 38, ON indicates paper detection, and OFF indicates paper non-detection.
“Feeding roller clutch” indicates the clutch 47, ON indicates a drive transmission state, and OFF indicates a non-transmission state.
“One-way clutch” indicates the one-way clutch 49, “invalid” indicates an invalid state of the one-way function (FIG. 9), and “valid” indicates an effective state of the one-way function (FIG. 10).
“Lifter” is the above-described lifter 40, and indicates the transition of ascent (UP) and descent (DOWN).

  Before the paper is fed, the state is as shown in FIG. 4, the lifter 40 is lowered, and the one-way function is disabled. When paper feeding is started from this state, the lifter 40 is first raised (time t1), whereby the uppermost paper P1 on the manual feed tray 41 contacts the feeding roller 15 as shown in FIG. Thereafter, the feeding roller clutch (clutch 47) is turned on and the one-way clutch 49 is activated (time t2), the feeding roller 15 is rotated forward, and the uppermost sheet P1 is fed as shown in FIG. The feed roller 15 is rotated from time t1 to time t5 as shown in FIG. The paper feeding by the rotation of the feeding roller 15 (time t1 to t5) is defined as “primary paper feeding”.

  The leading edge of the sheet P1 sent out by the primary sheet feeding reaches the pre-registration sensor 38 (time t3). When the pre-registration sensor 38 detects the leading edge of the paper, the registration brake (brake means 59) is turned on (time t4). Thereby, the registration roller pair 17 is in a state in which the rotation is restricted. In this state, primary paper feeding is continued until time t5. In the process up to the end of the primary paper feeding, the leading edge of the fed paper P1 is abutted against the registration roller pair 17, and a deflection Q is formed between the registration roller pair 17 and the feeding roller 15 as shown in FIG. The Due to this deflection Q, the leading edge of the paper P1 follows the registration roller pair 17 in the paper width direction (the front and back direction in FIG. 6), and the skew is corrected.

  At the time of this skew correction, the registration brake (brake means 59) is ON, so that the registration roller pair 17 is surely stopped, and the one-way clutch 49 is effective so that the feed roller 15 is reversely rotated. Thus, the deflection Q can be reliably formed between the registration roller pair 17 and the feeding roller 15, and the skew can be reliably corrected. In addition, the deflection Q can be reliably formed regardless of the rigidity (stiffness) of the paper, and the skew can be reliably corrected.

  Next, the registration brake (brake means 59) is turned off (time t6), the registration clutch (clutch 58) is turned on (time t7), and normal rotation of the registration roller pair 17 is started. At the same time, the feeding roller clutch (clutch 47) is turned on, and the forward rotation of the feeding roller 15 is resumed. Then, the paper P1 is conveyed while the registration roller pair 17 and the feeding roller 15 are rotated synchronously (time t7 to t10). Paper feeding by the synchronous rotation (time t7 to t10) of the registration roller pair 17 and the feeding roller 15 is defined as “secondary paper feeding”.

In the process up to the end of the secondary paper feeding, the leading edge of the paper P1 passes the pre-printing sensor 39 (time t8), and recording is started (time t9).
When the secondary paper feeding is completed (time t10) and the trailing edge of the paper P1 passes the pre-registration sensor 38 (time t11), the registration clutch (clutch 58) is turned off after a predetermined time (time t12). . Thereafter, when the recording is completed, the lifter 40 is lowered (time t13), and the one-way clutch 49 is disabled (time t14).
The above is an example of the operation from paper feeding to recording completion.

  Next, processing when a paper jam occurs will be described with reference to FIG. The control described above with reference to FIG. 12, particularly the control of the one-way clutch 49, is processing during normal printing. When a paper jam occurs, the control shown in FIG. 13 is performed in this embodiment.

  After feeding is started (step S101), the control unit 9 switches the one-way clutch 49 from invalid to valid (step S102: time t2 in FIG. 12). Thereafter, in this embodiment, the one-way clutch 49 is in a state where a paper jam occurs before the front end of the paper passes through the pre-printing sensor 39 and a case where a paper jam occurs after the front end of the paper passes through the pre-printing sensor 39. Are different.

More specifically, when a paper jam is detected before the leading edge of the paper passes through the pre-printing sensor 39 (Yes in step S103), the one-way clutch 49 is switched from valid to invalid (step S107). Then, error processing such as displaying a paper jam alert is performed.
If a paper jam is detected after the leading edge of the paper passes through the pre-printing sensor 39 (Yes in step S104) (Yes in step S105), a paper jam occurrence alert is displayed while the one-way clutch 49 is maintained valid. Perform error processing such as This process is continued until the recording is completed (Yes in step S106) or until the trailing edge of the sheet passes through the pre-printing sensor 39.
Note that jam detection can be performed by detecting whether the leading edge of the paper passes through the sensors (38, 39) within a specified time.

  Hereinafter, the effect of such processing will be described. If a paper jam is detected before the leading edge of the sheet passes through the pre-printing sensor 39, no recording is performed on the sheet, and the trailing edge of the sheet remains on the manual feed tray 41 (for example, the sheet P1 in FIG. 5). The sheet is pulled out from the manual feed tray 41. At this time, if the one-way clutch 49 is effective, the feeding roller 15 cannot be reversed, and a large force is required for pulling out the paper, or it cannot be pulled out. However, as described above, when the paper jam is detected before the front end of the paper passes through the pre-printing sensor 39, the one-way clutch 49 is invalidated (step S107), so that the paper can be easily pulled out with a light force.

On the other hand, if a paper jam is detected after the leading edge of the paper has passed through the pre-printing sensor 39, there is a high possibility that recording has been performed on the paper. In this case, if the paper is easily pulled out from the manual feed tray 41 side, the ink attached to the recording surface may adhere to the rollers or the path forming member on the transport path. Therefore, when there is such a possibility, the effective state of the one-way clutch 49 is maintained so that the sheet is not easily pulled out from the manual feed tray 41 side.
Then, by guiding an appropriate jam processing method to the user, for example, the transport unit 34 is pulled out from the printer main body, and the paper transport path is exposed at a position near the pair of transport rollers 19 so that the jam processing is performed. In this case, it is possible to avoid or suppress the ink adhering to the paper from adhering to the rollers and the path forming member on the transport path.

  Specifically, when the printer 1 opens the opening / closing cover 6 (FIG. 1), the driven roller 17b constituting the registration roller pair 17 is separated from the driving roller 17a, and the driven roller 18b constituting the transport roller pair 18 is separated. Is separated from the drive roller 18a (details are not shown). Therefore, by appropriately opening the opening / closing cover 6 (FIG. 1) during paper jam processing, it is possible to avoid ink adhering to the paper from adhering to the driven rollers 17b and 18b.

The characteristics of the printer 1 described above are summarized as follows. The printer 1 includes a manual feed tray 41 on which paper is placed, a feed roller 15 that feeds paper from the manual feed tray by forward rotation, a separation roller 16 that nips and separates the paper between the feed roller 15, a jam Sensors 38 and 39 are provided as jam detecting means for detecting. Furthermore, a one-way clutch 49 that realizes a one-way function that allows forward rotation of the feeding roller 15 and restricts reverse rotation of the feeding roller 15, and switching means 53 that switches on / off of the one-way function of the one-way clutch 49 are provided. Yes.
Then, on / off switching of the one-way function is executed in accordance with the detection result of the jam detection means. Accordingly, by turning on and off the one-way function according to the jam state, it is possible to ensure the handling of the paper during the jam processing.

At least before feeding paper from the manual feed tray 41, the one-way function of the one-way clutch 49 is off, and after the paper feed from the manual feed tray 41 is started, the switching unit 53 turns on the one-way function to at least feed the paper. After the recording is completed, the switching means 53 turns off the one-way function.
Accordingly, by turning on the one-way function, the reverse rotation of the feeding roller 15 can be restricted, and the skew correction can be reliably performed. Further, by turning off the one-way function, it is possible to allow the reverse rotation of the feeding roller 15 and easily remove the paper.
Further, when the one-way function is off, when the paper on the manual feed tray 41 is replaced, even if the uppermost paper enters between the feeding roller 15 and the separation roller 16 and is nipped, it is easily removed. Can be pulled out.

  In the case of paper jam processing, for example, if the driven rollers 17b and 18b are separated from the drive rollers 17b and 18b when the opening / closing cover 6 is opened, the paper can be easily pulled out. However, if the feeding roller 15 is also configured to be separated from the separation roller 16, the apparatus is increased in size. By enabling on / off switching of the one-way function, a mechanism for separating the feeding roller 15 from the separation roller 16 becomes unnecessary, and an increase in size of the apparatus can be suppressed.

  In addition, a pre-printing sensor 39 is provided between the feeding roller 15 and the recording head 8 in the paper transport path as detection means for detecting paper passage, and the paper before the pre-printing sensor 39 detects paper passage is provided. When a jam is detected, the switching means 53 turns off the one-way function of the one-way clutch 49. Therefore, the reverse rotation of the feeding roller 15 is allowed, and the jammed paper can be easily removed.

  When the pre-printing sensor 39 detects a paper jam after detecting the passage of the leading edge of the paper, the switching unit 53 turns on the one-way function of the one-way clutch 49. That is, when the pre-printing sensor 39 detects a paper jam after detecting the passage of the leading edge of the paper, it is highly likely that recording has been performed on the paper. In this case, if the jammed paper is pulled out carelessly, the inside of the apparatus may be soiled by undried ink. However, when the pre-printing sensor 39 detects a paper jam after detecting the passage of the leading edge of the paper, the switching means 53 turns on the one-way function of the one-way clutch 49, so that the paper on which the recording has been performed is pulled out carelessly. It is possible to avoid fouling the inside of the apparatus.

  Further, the switching means 53 holds the clutch portion 50 that realizes the one-way clutch function and is separated from a state (FIG. 10) that engages with the gear portion 51 as a rotating body that includes a plurality of tooth portions 51 a along the outer periphery. The state (FIG. 9) can be switched, and by engaging with the tooth part 51a, the rotation of the gear part 51 is constrained to turn on the one-way function, and by separating from the tooth part 51a, the gear part 51 is rotated. A lever 55 that permits and turns off the one-way function is provided. In this way, the switching means 53 has a simple structure and is configured at low cost.

  Moreover, the tooth part 51a with which the gear part 51 is provided is formed diagonally as shown in the enlarged view enclosed with the dashed-dotted line in FIG. This oblique direction is a direction that opposes the reverse rotation of the feeding roller 15 (the rotation of the gear portion 51 in the counterclockwise direction in FIG. 10). As a result, the ON state of the one-way function can be reliably maintained (the engagement between the tooth portion 51a and the locking portion 55b can be reliably maintained), and eventually the sheet is bent between the feeding roller 15 and the registration roller pair 17. (Described later) can be formed reliably.

  Further, in this aspect, a brake means 59 is provided that applies a brake to the rotation of the registration roller pair 17. Therefore, when the registration roller pair 17 is stopped, the registration roller pair 17 can be prevented from rotating when the leading edge of the sheet is abutted against the registration roller pair 17 to correct the sheet skew. it can.

  The brake means 59 can also be used to stop the rotation due to the inertia of the registration roller pair 17. For example, if the registration roller pair 17 continues to rotate due to inertia, the skew correction of the subsequent sheet cannot be performed, and if a waiting time is provided to wait for the rotation of the registration roller pair 17 to stop, throughput is reduced. Invite. However, since the rotation due to the inertia of the registration roller pair 17 can be stopped by the brake means 59, the above-described problem can be solved.

  Instead of the configuration in which the front end of the sheet is abutted against the registration roller pair 17, the front end of the sheet is abutted against the recording roller 8 immediately before the conveyance roller pair 18 on the upstream side in the conveyance direction, and the conveyance roller after the abutment. The skew may be corrected by driving the pair 18.

DESCRIPTION OF SYMBOLS 1 Inkjet printer, 2A apparatus main body, 2B, 2C expansion unit, 3 scanner part, 4 face down discharge tray, 5 operation panel, 6 open / close cover, 7 face up discharge tray, 8 recording head, 9 control part, 10A- 10C Paper cassette, 11 Hopper, 12 Feed roller, 13 Separation roller pair, 14 Transport roller pair, 15 Feed roller, 15a Rotating shaft, 16 Separation roller, 17 Registration roller pair, 18-29 Transport roller pair, 31 1st Flap, 32 second flap, 33 flap, 34 transport unit, 35 feeding unit, 36 friction member, 37-39 sensor, 40 lifter, 41 manual feed tray, 42 edge guide, 44 motor, 45 gear group, 47 clutch, 47a Transmission gear, 47 Received part, 49 One-way clutch, 50 Clutch part, 51 Gear part, 53 Switching means, 54 Solenoid, 55 Lever, 55a Oscillating shaft, 55b Locking part, 56 Tension spring, 58 Registration clutch, 59 Brake means, 60 Motor 61 gear group, F drive roller, G driven roller, R1 recording transport path (first transport path), R2 switchback path (second transport path), R3 reverse path (third transport path), R4 face down discharge path (Fourth transport path), R5 face-up discharge path (fourth transport path), P, P1, P2, P3, P4, P5 recording paper, S1 cassette feeding locus, S2 additional cassette feeding locus, S3 manual feeding Trajectory, T1 Face up discharge trajectory, T2 Face down discharge trajectory

Claims (5)

A medium placement unit for placing a medium;
A feeding roller that feeds the medium from the medium placing unit by forward rotation;
A separation unit that nips and separates the medium from the feeding roller;
A recording head that is positioned downstream of the separation unit in the medium conveyance direction and performs recording on the medium;
A motor for applying a driving torque to the rotation shaft of the feeding roller;
A one-way clutch that realizes a one-way function that allows forward rotation of the feeding roller and restricts reverse rotation of the feeding roller;
Switching means for switching on and off the one-way function;
And jam detecting means for detecting jam of the medium,
Depending on the detection result of the jam detection means, the switching means performs on-off switching of the one-way function.
A recording apparatus. The recording apparatus according to claim 1, further comprising a detection unit configured to detect the passage of the medium that constitutes the jam detection unit between the feeding roller and the recording head in a conveyance path of the medium.
If a media jam occurs with the leading edge of the medium upstream of the detection means, the switching means turns off the one-way function,
A recording apparatus. The recording apparatus according to claim 2, wherein when the detection unit detects a jam of the medium after detecting the passage of the leading end of the medium, the switching unit maintains the one-way function on.
A recording apparatus. The recording apparatus according to any one of claims 1 to 3, wherein the switching unit holds the one-way clutch and includes a rotating body having a plurality of teeth along an outer periphery thereof.
It is possible to switch between a state engaging with the tooth part and a state separating from the tooth part, and by engaging with the tooth part, the rotation of the rotating body is constrained to turn on the one-way function, and the tooth An engagement member that allows the rotation of the rotating body by separating from the part and turns off the one-way function,
A recording apparatus. The recording apparatus according to claim 4, wherein the tooth portion is formed obliquely in a direction that opposes the reverse rotation of the feeding roller.
A recording apparatus.

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