JP6435876B2 - Paper feeder - Google Patents

Description

The present invention is also the in is related to the sheet feeding apparatus to be installed in the image forming apparatus typified by a copier.

  The paper feeding device is mounted in an image forming apparatus such as a copying machine, a printer, or a facsimile machine in order to send a sheet as a transfer material to an image forming unit. In some cases, the paper feeding device is provided with a plurality of sensors such as a sensor for detecting the presence or absence of paper and a sensor for detecting whether or not paper feeding has been performed reliably. In addition, there has been a concern about an increase in cost associated with the provision of a plurality of sensors and an increase in size of the apparatus due to an increase in the occupied area. Japanese Patent Application Laid-Open No. 2004-133867 discloses a related art related to a paper feeding apparatus proposed to solve such a problem.

  In the paper feeding device described in Patent Document 1, a sensor having a light emitting portion and a light receiving portion is provided at a paper outlet. When the sensor is viewed from the side, the light emitting unit and the light receiving unit are arranged so that the optical path crosses the sheet take-out port in an oblique direction. This sheet feeding device detects the presence or absence of a sheet and a sheet feeding failure by a signal from a sensor during operation and non-operation of the sheet lift mechanism and during sheet feeding.

JP-A-6-144642

  However, the conventional paper feeder cannot detect the leading edge of the paper depending on the location of the sensor, and it is difficult to determine whether or not the paper has been reliably fed when the paper is buckled. There was a problem. Further, in order to detect the presence or absence of a sheet, a lifting operation of the sheet lift mechanism is required, which causes a problem that productivity is deteriorated.

  The present invention has been made in view of the above points, and provides a paper feeding device capable of suitably determining the presence or absence of paper and whether or not paper feeding has been performed reliably using a single sensor. The purpose is to provide.

  In order to solve the above-described problems, a paper feeding device according to the present invention includes a paper storage unit that stacks and stores paper, a paper supply roller that feeds the paper to the outside of the paper storage unit, and a paper supply roller that supplies the paper. A paper feed sensor that is disposed downstream in the paper direction and detects paper fed out of the paper storage unit, and a displacement unit that is displaced in accordance with the remaining amount of paper stacked in the paper storage unit. The paper feed sensor detects the presence or absence of paper stacked in the paper storage unit based on the displacement of the displacement unit.

  According to this configuration, since the paper feed sensor is disposed downstream of the paper feed roller in the paper feed direction, the front end of the paper during paper feed is detected. Further, since the paper feed sensor detects the presence or absence of the paper based on the operation of the displacement portion that is displaced corresponding to the remaining amount of paper, it is not necessary to raise or lower the paper for the detection.

  Further, in the sheet feeding device having the above configuration, the abutting member abuts on an upper surface of the uppermost sheet stacked on the sheet accommodating unit and is displaced corresponding to the remaining amount of the sheet, and the abutting member And a shutter member that moves in conjunction with the displacement of the sheet, and the paper feed sensor detects the presence or absence of the paper stacked in the paper storage unit based on the position of the shutter member.

  Further, in the sheet feeding device having the above-described configuration, a shaft portion for rotationally displacing the contact member, a protrusion provided on the contact member and disposed at a location separated from the shaft portion, A groove formed on the shutter member and having a shape for moving the shutter member between a position where the protrusion is engaged and the paper feed sensor detects the presence of paper and a position where no paper is detected. It is characterized by.

  In the sheet feeding device having the above-described configuration, the shutter member is disposed with a gap of a predetermined distance from one end in the axial direction of the sheet feeding roller.

  Further, in the sheet feeding device having the above-described configuration, the sheet storage unit is detachable from the sheet feeding device main body, and the shutter member moves in parallel with the mounting / demounting direction of the sheet storage unit.

  Further, in the sheet feeding device having the above-described configuration, the shutter member is a part of a conveyance path for a sheet fed out of the sheet storage unit.

  Further, in the sheet feeding device having the above-described configuration, the displacement unit includes a delay mechanism that moderately displaces the displacement unit after the last sheet of the sheet in the sheet storage unit passes through the position of the displacement unit. It is characterized by.

  According to the configuration of the present invention, it is possible to detect the leading edge of the paper at the time of paper feeding, and therefore it is possible to determine whether or not paper feeding has been performed reliably even when the paper is buckled or the like. Is possible. Furthermore, since there is no need to raise and lower the paper in order to detect the presence or absence of the paper, it is possible to improve productivity. Therefore, it is possible to suitably determine whether or not a sheet is present and whether or not a sheet has been reliably fed using one sensor.

1 is a plan view of a sheet feeding device according to a first embodiment of the present invention. 1 is a side view of a sheet feeding device according to a first embodiment of the present invention. 1 is a perspective view of a sheet feeding device according to a first embodiment of the present invention. FIG. 3 is a partial perspective view of the periphery of the supply unit of the sheet feeding device according to the first embodiment of the present invention. FIG. 3 is a partial perspective view of the periphery of the supply unit of the sheet feeding device according to the first embodiment of the present invention, showing a lift-up state. FIG. 3 is a side view of a supply unit of the paper feeding device according to the first embodiment of the present invention. FIG. 3 is a perspective view of a supply unit of the sheet feeding device according to the first embodiment of the present invention. FIG. 3 is a perspective view of a displacement unit of a sheet detection unit of the sheet feeding device according to the first embodiment of the present invention. 6 is a flowchart illustrating an example of paper feeding processing by the paper feeding device according to the first embodiment of the present invention. It is a perspective view of the displacement part of the paper detection part of the paper feeder which concerns on 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the following contents.

<First Embodiment>
First, the outline of the structure of the sheet feeding device according to the first embodiment of the present invention will be described with reference to FIGS. 1, 2, and 3. 1, 2 and 3 are a plan view, a side view and a perspective view of the sheet feeding device. In addition, the white arrow in the drawing indicates the direction in which the paper cassette is pulled out and pushed in (the front-rear direction of the paper feeder). Further, in FIG. 2 and FIG. 3, the drawing of the main body housing of the sheet feeding device is omitted. FIG. 2 is a view of the sheet feeding device viewed from the upstream side in the sheet feeding direction of the sheet feeding device.

  The sheet feeding device 1 includes a main body housing 2 and a sheet feeding cassette 3 as shown in FIGS. The paper feed cassette 3 is a paper storage unit that stacks and stores paper such as cut paper before printing. The paper feed cassette 3 is formed in a flat box shape with an open top surface, and stacks and accommodates paper from the top surface direction. Note that the sheet is sent out to the right in FIG.

  The paper feed cassette 3 is provided on the side surface thereof, and a horizontal protrusion 3 a extending in the front-rear direction protruding sideways is engaged with a guide rail (not shown) inside the main body case 2, whereby the main body case is provided. 2 can be slid horizontally. The paper feed cassette 3 can be attached to and detached from the main body housing 2 by pulling out or pushing in the front-rear direction.

  A push-up plate 4 is disposed on the inner bottom surface of the paper feed cassette 3. The sheets are placed on the push-up plate 4 and stacked. The push-up plate 4 is supported on the inner bottom surface of the paper feed cassette 3 by a support shaft 4a that extends in the front-rear direction provided at the upstream end in the paper feed direction, that is, the left end in FIG. The push-up plate 4 can swing around the support shaft 4a with the downstream end as a free end.

  A lift mechanism (not shown) for the push-up plate 4 is disposed below the upstream portion of the push-up plate 4 in the paper feed direction between the push-up plate 4 and the inner bottom surface of the paper feed cassette 3. The lift mechanism includes a rotating shaft and a lift piece. The rotating shaft extends in the front-rear direction along the inner bottom surface of the sheet feeding cassette 3, and a lift piece is fixed to the front end thereof. The lift piece is arranged at the center in the front-rear direction of the push-up plate 4, the rotary shaft is fixed at one end, and the other end contacts the lower surface of the push-up plate 4 at the upstream portion in the sheet feeding direction. The rear end of the rotating shaft protrudes further rearward from the rear surface of the paper feed cassette 3.

  When the paper feed cassette 3 is mounted on the main body housing 2, the rear end of the rotary shaft is connected to a drive unit (not shown) provided on the main body housing 2. And if the drive part is operated, a rotating shaft and a lift piece will rotate, and the sheet feeding direction upstream part of the push-up board 4 pushed up by a lift piece will raise. When the connection between the rotary shaft and the drive unit is released by pulling out the paper feed cassette 3 from the main body housing 2, the push-up plate 4 falls on the inner bottom surface of the paper feed cassette 3.

  A supply unit 10 is disposed in the main body housing 2 above the downstream portion of the sheet feeding cassette 3 in the sheet feeding direction. The supply unit 10 sends out the paper in the paper feed cassette 3 to the outside of the paper feed cassette 3.

  Next, the detailed structure of the supply unit 10 will be described with reference to FIG. FIG. 4 is a partial perspective view of the periphery of the supply unit 10 of the paper feeding device 1 and shows a state in which there is no paper in the paper feeding cassette 3.

  As shown in FIG. 4, the supply unit 10 includes a pickup roller 11, a paper feed roller 12, a separating roller 13, a drive mechanism 14, a support member 15, an upper limit sensor 16, and a paper detection unit 20.

  The pickup roller 11 is arranged above the downstream portion of the push-up plate 4 in the sheet feeding direction. The downstream portion of the paper stacked on the paper feed cassette 3 is lifted by the push-up plate 4 from below the pickup roller 11, and the uppermost paper of the paper feed cassette 3 presses the pickup roller 11 from below and comes into contact. The paper in the paper feed cassette 3 is delivered to the paper feed roller 12 by the pickup roller 11 and is sent out of the paper feed cassette 3 by the paper feed roller 12.

  The paper feed roller 12 is disposed downstream of the pickup roller 11 in the paper feed direction. The sheet feed roller 12 is provided so that the lower part of the surface of the sheet feed roller 12 projects into the sheet conveyance path 5 extending from the sheet feed device 1 to the outside. The paper feed roller 12 is connected to a motor (not shown).

  A drive mechanism 14 for the pickup roller 11 is disposed between the paper feed roller 12 and the pickup roller 11. The drive mechanism 14 has a plurality of gears connected to each other, and the paper feed roller 12 and the pickup roller 11 are connected via the drive mechanism 14. When the paper feed roller 12 is rotated by the motor, the pickup roller 11 is also rotated in the same direction as the paper feed roller 12 by the driving mechanism 14 at the same peripheral speed.

  The pick-up roller 11 and the paper feed roller 12 are both rotatably supported by the support member 15 at their shaft portions 11a and 12a. The support member 15 is provided in the main body housing 2 so as to be swingable about the shaft portion 12 a of the paper feed roller 12. As a result, the pickup roller 11 portion of the support member 15 can swing about the shaft portion 12 a of the paper feed roller 12.

  The portion of the pickup roller 11 of the support member 15 is urged downward by an urging member (not shown) or gravity. An upper limit sensor 16 detects whether or not the uppermost sheet of the sheet feeding cassette 3 pushed up by the lift mechanism of the push-up plate 4 has contacted the pickup roller 11. The upper limit sensor 16 is composed of, for example, a transmissive optical sensor, and detects that a predetermined portion of the support member 15 is raised and blocks its optical path. For example, when a sheet is placed on the push-up plate 4, the upper limit sensor 16 detects that the uppermost sheet of the sheet feeding cassette 3 has come into contact with the pickup roller 11 by raising the support member 15. Then, the lifting of the push-up plate 4 by the lift mechanism is stopped, and the uppermost sheet of the sheet feeding cassette 3 reaches a predetermined sheet feeding position where it contacts the pickup roller 11.

  The separating roller 13 is disposed below the sheet feeding roller 12 with the sheet conveyance path 5 interposed therebetween. The roller 13 presses and contacts the paper feed roller 12 by the action of a biasing member (not shown). The sheet is inserted through a nip formed by the contact between the separating roller 13 and the sheet feeding roller 12. The roller 13 is not connected to a motor but rotates according to the rotation of the paper feed roller 12 by contacting the paper feed roller 12.

  The roller 13 is provided with, for example, a torque limiter (not shown) on its shaft portion 13a. When there is no sheet in the nip formed by the contact between the sheet roller 13 and the sheet feeding roller 12 or when only one sheet enters, the sheet roller 13 is subjected to a torque greater than the torque limiter set torque, The winding roller 13 rotates in the direction of feeding the paper according to the paper feed roller 12. On the other hand, when a plurality of paper sheets enter the nip portion, the torque applied to the roller 13 becomes less than the torque limiter setting torque, and the roller 13 stops rotating. As a result, since the overlapped lower sheets are not sent out, it is possible to prevent the problem of double feeding that the sheets are overlapped and fed.

  The paper detection unit 20 is disposed above the downstream portion of the paper feed cassette 3 in the paper feed direction and in front of the pickup roller 11 and the paper feed roller 12. The paper detection unit 20 detects the presence or absence of paper in the paper feed cassette 3 and whether or not the paper supply is reliably performed by the supply unit 10.

  Next, the detailed structure and operation of the paper detection unit 20 will be described with reference to FIGS. 5 to 9 in addition to FIG. FIG. 5 is a partial perspective view around the supply unit 10 and shows a lift-up state. 6 and 7 are a side view of the supply unit 10 (viewed from the upstream side in the paper feeding direction) and a perspective view (viewed from below). FIG. 8 is a perspective view of the displacement portion of the paper detection unit 20. FIG. 9 is a flowchart illustrating an example of paper feeding processing by the paper feeding device 1.

  As shown in FIG. 4, the paper detection unit 20 includes a paper feed sensor 21, a sensor support unit 22, and a displacement unit 30. The displacement part 30 includes a contact member 31 and a shutter member 32.

  The paper feed sensor 21 is disposed downstream of the paper feed roller 12 in the paper feed direction and above the paper transport path 5 extending from the paper feed device 1 to the outside thereof. The paper feed sensor 21 is supported by the sensor support portion 22 and provided in the main body housing 2.

  The paper feed sensor 21 is composed of, for example, a reflection type optical sensor, and integrally includes a light emitting unit and a light receiving unit (both not shown). The light emitting unit is formed of, for example, a light emitting diode, and emits irradiation light that is emitted toward the paper passing through the paper conveyance path 5. The light receiving unit is formed of, for example, a phototransistor, and receives light reflected by the paper surface of the irradiation light emitted from the light emitting unit. When the light receiving unit receives the reflected light, the sheet feeding device 1 detects that the sheet is sent out to the outside of the sheet feeding cassette 3 by the supply unit 10 and the sheet feeding is reliably performed.

  The abutting member 31 is disposed in front of the pickup roller 11 and above the downstream portion of the push-up plate 4 in the sheet feeding direction. The contact member 31 is formed in a plate shape extending in the up-down direction and the front-rear direction, and is provided to be rotatable about a shaft portion 31 a that extends along the paper feeding direction connected to the main body housing 2. The contact member 31 is provided with a shaft portion 31a on one end side, a contact portion 31b is provided on the other end side, and is rotationally displaced within a plane in which the contact portion 31b side intersects the sheet feeding direction with the shaft portion 31a as a center. To do.

  When there is no sheet in the paper feed cassette 3, the contact member 31 is rotationally displaced by the action of gravity as shown in FIG. 4, and the contact portion 31 b comes into contact with the inner bottom surface of the paper feed cassette 3. An opening 4b is provided at a position corresponding to the abutting member 31 of the push-up plate 4, and the abutting part 31b is inserted into the opening 4b when there is no sheet in the paper feed cassette 3. On the other hand, when there is a sheet in the sheet feeding cassette 3, the contact member 31 contacts the uppermost sheet of the sheets P stacked on the sheet feeding cassette 3 and rotates in accordance with the remaining amount of the sheet P as shown in FIG. Displace.

  The shutter member 32 is disposed in front of the pickup roller 11 and the paper feed roller 12 and downstream of the contact member 31 in the paper feed direction. The shutter member 32 is formed in a box shape with an upper surface and a front surface opened, and a bottom surface and a downstream side surface of the shutter member 32 are a part of the sheet conveyance path 5. As shown in FIGS. 4 and 5, the shutter member 32 has a shape and size that can accommodate a part of the sensor support portion 22 and the paper feed sensor 21 inside a box shape.

  Further, as shown in FIGS. 6 and 7, the shutter member 32 is disposed forward from a front end in the axial direction of the paper feed roller 12 with a gap of a predetermined distance. The shutter member 32 engages with a guide member (not shown) provided in the main body housing 2 and is movable in the front-rear direction of the paper feeding device 1, that is, parallel to the attachment / detachment direction of the paper feeding cassette 3 with respect to the main body housing 2. Installed.

  When the shutter member 32 moves forward, the paper feed sensor 21 is accommodated inside thereof, and the optical path of the paper feed sensor 21 is shielded by the shutter member 32. On the other hand, when the shutter member 32 moves rearward, the paper feed sensor 21 is exposed from the inside to the paper transport path 5, and the optical path of the paper feed sensor 21 is opened toward the paper transport path 5.

  The contact member 31 and the shutter member 32 are engaged with each other, and the shutter member 32 moves in conjunction with the rotational displacement of the contact member 31. As shown in FIG. 8 regarding the engagement between the contact member 31 and the shutter member 32, the contact member 31 includes a protrusion 31c, and the shutter member 32 includes a groove 32a.

  The protrusion 31c of the contact member 31 is disposed at a location near the contact portion 31b that is separated from the shaft portion 31a. The protruding portion 31c protrudes toward the upstream side of the sheet feeding direction, that is, toward the shutter member 32 along the axial direction of the shaft portion 31a.

  The groove portion 32a of the shutter member 32 has a curved shape so as to form, for example, an arc shape in a plane in which the contact member 31 is rotationally displaced. The groove 32a has a width that allows the protrusion 31c of the contact member 31 to be inserted therethrough, and the protrusion 31c is inserted and engaged therewith. The position of the lower end of the groove 32a corresponds to the position of the protrusion 31c when the abutting member 31 assumes a position in which the abutting part 31b of the abutting member 31 is inserted into the opening 4b of the push-up plate 4 (see FIG. 4). To do. The position of the upper end of the groove portion 32a corresponds to the position of the protrusion 31c when the contact portion 31b of the contact member 31 that rotates and displaces in contact with the uppermost sheet of the paper P is in the uppermost position. In addition, the shape of the groove part 32a is not necessarily limited to the shape demonstrated here, Other shapes may be sufficient.

  When there is no paper P in the paper feed cassette 3 at the stage of detecting the presence or absence of the paper P, as shown in FIGS. 4 and 8, the shutter member 32 engaged with the contact member 31 via the protrusion 31c and the groove 32a is In conjunction with the rotational displacement of the contact member 31, it moves most forward in the front-rear direction. At this time, the shutter member 32 accommodates the paper feed sensor 21 in a box-like shape, and shields the optical path of the irradiation light emitted from the light emitting unit of the paper feed sensor 21. Thereby, the light receiving unit of the paper feed sensor 21 receives the reflected light from the shutter member 32 of the irradiation light emitted from the light emitting unit. When the light receiving unit receives the reflected light at the stage of detecting the presence or absence of the paper P, the paper feeding device 1 detects that there is no paper P in the paper feeding cassette 3.

  On the other hand, when there is a sheet P in the sheet feeding cassette 3 at the stage of detecting the presence or absence of the sheet P, the shutter member 32 is interlocked with the rotational displacement of the abutting member 31 and there is no sheet as shown in FIGS. Compared to move backwards. At this time, the paper feed sensor 21 is exposed to the paper transport path 5 from the inside of the shutter member 32, and the light path of the irradiation light emitted from the light emitting unit of the paper feed sensor 21 is not blocked by the shutter member 32. Accordingly, the light receiving unit of the paper feed sensor 21 does not receive the reflected light from the shutter member 32 of the irradiation light emitted from the light emitting unit. When the light receiving unit does not receive the reflected light at the stage of detecting the presence or absence of the paper P, the paper feeding device 1 detects that the paper P is in the paper feeding cassette 3.

  Next, an example of paper feeding processing by the paper feeding device 1 will be described with reference to FIGS. 4 and 5 along the flow shown in FIG.

  In response to the paper feed command, the paper feed device 1 starts a series of paper feed processes. In step # 101 of FIG. 9, it is determined whether or not the paper feed cassette 3 has been attached to the main body casing 2. If the paper feed cassette 3 has been attached to the main body housing 2, the process proceeds to step # 102. If the paper feed cassette 3 is not attached to the main body housing 2, the determination in step # 101 is repeated. Note that whether or not the paper feed cassette 3 is already attached to the main body housing 2 is detected by a sensor (not shown).

  In step # 102, the lift-up plate 4 is lifted up. The lift-up plate 4 is lifted up by the lift mechanism of the push-up plate 4 as described above.

  In step # 103, the upper limit sensor 16 detects the rising of the support member 15, and it is determined whether the push-up plate 4 or the paper P has contacted the pickup roller 11. If the upper limit sensor 16 detects the rise of the support member 15, the process proceeds to step # 105, and if not detected, the process proceeds to step # 104.

  In step # 104, the paper feeder 1 notifies the lift-up abnormality. For example, information on lift-up abnormality is transmitted to the control unit of the image forming apparatus on which the sheet feeding device 1 is mounted, and is performed using an operation panel or the like. Then, the sheet feeder 1 ends the sheet feeding process.

  In step # 105, the paper feed sensor 21 determines whether or not there is paper P in the paper feed cassette 3.

  When there is no paper P in the paper feed cassette 3 (see FIG. 4), the contact member 31 is rotationally displaced by the action of gravity as described above, and the contact portion 31b is inserted into the opening 4b of the push-up plate 4. The shutter member 32 moves most forward in conjunction with the rotational displacement of the contact member 31, and blocks the optical path of the irradiation light emitted from the light emitting unit of the paper feed sensor 21. The light receiving unit receives the reflected light from the shutter member 32 of the emitted light emitted from the light emitting unit of the paper feed sensor 21, and the paper feed device 1 detects that there is no paper P in the paper feed cassette 3. If there is no paper P in the paper feed cassette 3, the process proceeds to step # 106.

  When there is paper P in the paper feed cassette 3 (see FIG. 5), as described above, the shutter member 32 is interlocked with the rotational displacement of the abutting member 31 and moves backward as compared with the case where there is no paper. The paper feed sensor 21 is exposed to the paper transport path 5. Since the light path of the emitted light emitted from the light emitting unit of the paper feed sensor 21 is not shielded by the shutter member 32 and the light receiving unit does not receive the reflected light, the paper feeding device 1 detects that the paper P is in the paper feeding cassette 3. To do. If there is paper P in the paper feed cassette 3, the process proceeds to step # 107.

  In step # 106, the paper feeding device 1 notifies that there is no paper P in the paper feeding cassette 3. For example, information indicating no paper is transmitted to the control unit of the image forming apparatus on which the paper feeding device 1 is mounted, and is performed using an operation panel or the like. Then, the sheet feeder 1 ends the sheet feeding process.

  In step # 107, the paper feeding operation is started. The paper P in the paper feed cassette 3 is delivered to the paper feed roller 12 by the pickup roller 11, the double feed is suppressed by the separation roller 13, and is sent out of the paper feed cassette 3 by the paper feed roller 12. At this time, the light receiving unit of the paper feed sensor 21 receives reflected light from the fed paper, and repeats light reception and non-light reception depending on the pitch between the papers.

  In step # 108, it is determined whether or not the paper P is sent out by the paper feed sensor 21 to the outside of the paper feed cassette 3 and the paper is reliably fed. That is, when the light receiving unit of the paper feed sensor 21 repeats light reception and non-light reception at the inter-paper pitch, it is determined that the paper supply is reliably performed, and the process proceeds to step # 110. On the other hand, if a predetermined time has passed while the light receiving portion of the paper feed sensor 21 is in the light receiving state, it is determined that a paper jam (paper feed failure) has occurred, and the process proceeds to step # 109.

  In step # 109, the paper feeder 1 notifies the occurrence of paper jam. For example, information on the occurrence of paper jam is transmitted to the control unit of the image forming apparatus in which the paper feeding device 1 is mounted, and information relating to the occurrence of paper jam is performed using an operation panel or the like. Then, the sheet feeder 1 ends the sheet feeding process.

  In step # 110, it is determined whether or not a predetermined number of fed sheets has been reached. If the designated number of sheets has not been reached, the process returns to step # 105. If the number has been reached, the sheet feeder 1 ends the sheet feeding process.

Second Embodiment
Next, a paper feeder according to a second embodiment of the present invention will be described with reference to FIG. FIG. 10 is a perspective view of the displacement portion of the paper detection unit of the paper feeder. Since the basic configuration of this embodiment is the same as that of the first embodiment described above, the same components as those of the first embodiment are denoted by the same reference numerals and the description thereof is omitted. And

  In the paper feeding device 1 according to the second embodiment, the displacement unit 30 of the paper detection unit 20 includes a delay mechanism 40 shown in FIG. The delay mechanism 40 includes a groove 41 and a braking member 42.

  The groove 41 is provided in the shutter member 32 in place of the groove 32a of the shutter member 32 described in the first embodiment. The groove 41 has a width that allows the protrusion 31c of the contact member 31 to be inserted just like the groove 32a, and the protrusion 31c is inserted and engaged therewith.

  The groove portion 41 has a curved shape in a plane in which the contact member 31 is rotationally displaced, but has a shape different from that of the groove portion 32a. In the groove 41, after the last sheet P of the paper P placed on the push-up plate 4 passes through the location of the contact member 31, the contact member 31 gradually moves downward as compared with the case of the groove 32a. And has a shape that rotates and displaces. Specifically, when the groove part 41 and the groove part 32a have, for example, an arc shape, the groove part 41 has a larger curvature than the groove part 32a.

  The braking member 42 is disposed at the position of the shaft portion 31 a of the contact member 31. The braking member 42 is a rotating speed reducing member, and is composed of, for example, a rotary damper that uses the viscous resistance of oil. The brake member 42 decelerates the contact member 31 and gently displaces it. When the braking member 42 is used, after the last sheet of the paper P placed on the push-up plate 4 passes through the location of the contact member 31, the contact member 31 is relatively moved as in the case of the groove portion 41. Slowly displaces downward.

  When the delay mechanism 40 is used, the displacement of the contact member 31 after the last sheet P of the sheet P in the sheet feed cassette 3 passes through the position of the contact member 31 becomes gentle. As a result, the time interval from when the paper feed sensor 21 detects that the paper has been reliably supplied to when it is detected that the paper P in the paper feed cassette 3 has run out is slightly longer (for example, about several tens of ms). ). Therefore, it becomes easy to distinguish between the fact that the paper feeding has been performed reliably and the paper P has run out.

  In addition, the shape of the groove part 41 is not necessarily limited to the shape demonstrated here, Other shapes may be sufficient. Further, the braking member 42 is not limited to the rotary damper, and other deceleration members may be used. Moreover, both the groove part 41 and the braking member 42 may be used simultaneously, or one of them may be used.

  As described above, the paper feeding device 1 has the paper feeding cassette 3 in which the paper P is stacked and stored, the paper feeding roller 12 that feeds the paper P to the outside of the paper feeding cassette 3, and the paper feeding direction from the paper feeding roller 12. A paper feed sensor 21 for detecting the paper P disposed downstream and fed out of the paper feed cassette 3, and a displacement portion that is displaced according to the remaining amount of the paper P loaded in the paper feed cassette 3 30. In the paper feeding device 1, the paper feeding sensor 21 detects the presence or absence of the paper P loaded in the paper feeding cassette 3 based on the displacement of the displacement unit 30.

  According to this configuration, the paper feed sensor 21 is disposed downstream of the paper feed roller 12 in the paper feed direction, and therefore detects the leading edge of the paper P during paper feed. Thereby, even when buckling or the like occurs in the paper P, it is possible to determine whether or not the paper has been reliably fed. Further, since the paper feed sensor 21 detects the presence or absence of the paper P based on the operation of the displacement unit 30 that is displaced corresponding to the remaining amount of the paper P, it is not necessary to raise or lower the paper P for the detection. Thereby, it is possible to improve productivity. Accordingly, it is possible to suitably determine whether or not the sheet P is present and whether or not the sheet feeding has been performed reliably by using one sheet feeding sensor 21.

  The displacement unit 30 abuts on the uppermost sheet of the sheets P stacked on the sheet feeding cassette 3 and is displaced in accordance with the remaining amount of the sheet P, and in conjunction with the displacement of the abutment member 31. And a moving shutter member 32. The paper feed sensor 21 detects the presence or absence of the paper P stacked in the paper feed cassette 3 based on the position of the shutter member 32.

  According to this configuration, the shutter member 32 moves in conjunction with the movement of the contact member 31 that is displaced corresponding to the remaining amount of the paper P. Since the paper feed sensor 21 detects the presence / absence of the paper P stacked in the paper feed cassette 3 based on the position of the shutter member 32, the presence / absence of the paper P can be detected with a simple configuration.

  The displacement portion 30 includes a shaft portion 31a for rotationally displacing the contact member 31, a projection portion 31c provided on the contact member 31 and spaced from the shaft portion 31a, and a shutter member 32. And a groove 32a having a shape for moving the shutter member 32 between the position where the protrusion 31c is engaged and the paper feed sensor 21 detects the presence of paper and the position where the paper absence is detected.

  According to this configuration, the contact member 31 can be easily displaced according to the remaining amount of the paper P. Furthermore, the shutter member 32 can be easily moved in conjunction with the movement of the contact member 31 via the protrusion 31c and the groove 32a. Therefore, it is possible to reliably detect the presence or absence of the paper P by the paper feed sensor 21.

  Further, the shutter member 32 is disposed with a gap of a predetermined distance from one end in the axial direction of the paper feed roller 12.

  According to this configuration, a sufficient space is formed around the paper feed roller 12. Accordingly, it is possible to easily perform maintenance such as replacement of the pickup roller 11 and the roller 13 in addition to the paper feed roller 12.

  Further, the paper feed cassette 3 can be attached to and detached from the main body housing 2, and the shutter member 32 moves in parallel with the attachment and detachment direction of the paper feed cassette 3.

  According to this configuration, the displacement portion 30 can be configured with a simple mechanism.

  The shutter member 32 is a part of the sheet conveyance path 5 for the sheet P sent out to the outside of the sheet feeding cassette 3.

  According to this configuration, for example, the sheet P can be prevented from entering the space outside the sheet conveyance path 5 due to the buckling of the sheet P or the like. Therefore, it is possible to improve the stability of the paper feeding operation of the paper feeding device 1.

  In addition, the displacement unit includes a delay mechanism that moderates the displacement of the displacement unit after the last sheet of the sheet in the sheet storage unit passes through the position of the displacement unit.

  According to this configuration, it is possible to ensure a relatively long time interval from the time when the paper feed sensor 21 detects that the paper has been reliably supplied to the time when it is detected that the paper P in the paper feed cassette 3 has run out. Can do. Therefore, it is possible to easily distinguish the fact that the paper feeding has been performed reliably and the paper P has been exhausted. Then, it becomes possible to more suitably determine the presence or absence of the paper P and whether or not the paper has been reliably fed using the paper feed sensor 21.

  Although the embodiments of the present invention have been described above, the scope of the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the invention.

  The present invention can be used in a paper feeder.

DESCRIPTION OF SYMBOLS 1 Paper feeder 2 Main body housing | casing 3 Paper feed cassette 4 Push-up board 4b Opening part 10 Supply part 12 Paper feed roller 20 Paper detection part 21 Paper feed sensor 30 Displacement part 31 Contact member 31a Shaft part 31b Contact part 31c Protrusion part 32 Shutter member 32a Groove 40 Delay mechanism 41 Groove 42 Braking member

Claims (5)

A paper storage unit for storing and storing paper;
A paper feed roller for feeding paper to the outside of the paper container;
A paper feed sensor that is disposed downstream of the paper feed roller in the paper feed direction and detects paper fed out of the paper container;
A displacement portion that is displaced in accordance with the remaining amount of paper stacked in the paper storage portion;
With
The displacement part is
An abutting member that abuts on the upper surface of the uppermost paper stacked in the paper accommodating portion and is displaced in accordance with the remaining amount of paper;
A shutter member that moves in conjunction with the displacement of the contact member;
A shaft portion for rotationally displacing the contact member;
A protrusion provided on the contact member and disposed at a location spaced from the shaft;
A groove formed on the shutter member and having a shape for moving the shutter member between a position where the protrusion is engaged and the paper feed sensor detects the presence of paper and a position where no paper is detected;
With
The paper feed device, wherein the paper feed sensor detects the presence or absence of paper stacked in the paper storage unit based on the position of the shutter member . The sheet feeding device according to claim 1 , wherein the shutter member is disposed with a gap of a predetermined distance from one end in the axial direction of the sheet feeding roller. The paper container is detachable from the paper feeder body,
The shutter member is sheet feeding apparatus according to claim 1 or claim 2, characterized in that moves parallel to the detachment direction of the sheet accommodating portion. The shutter member is sheet feeding apparatus according to any one of claims 1 to 3, characterized in that the part of the conveying path of the sheet fed out to the outside of the sheet accommodating portion. The said displacement part is provided with the delay mechanism in which the displacement of the said displacement part after the last sheet of the paper of the said paper storage part passes the location of the said displacement part is made loose. The sheet feeding device according to any one of 4 .