JP7147159B2 - Sheet feeding device and image forming device - Google Patents

Description

The present invention relates to a sheet feeding device and an image forming device.

The paper feeding device described in Patent Document 1 includes an urging portion, a sheet stacking cassette, a sheet stacking table, side detection means, and a paper feeding roller. The sheet stacking cassette is accommodated in the housing of the copier. The biasing body biases the sheet stacking table upward. The side detecting means detects the remaining amount of sheets on the sheet stacking table by detecting the side surface of the sheet stacking table when the remaining amount of sheets becomes equal to or less than a predetermined number of sheets.

JP-A-4-308135

However, when a sheet enters the upper portion of the holder (supporting portion) that supports the paper feed roller, an abnormal state occurs in which the holder cannot reach a predetermined position due to the obstruction of the sheet. The predetermined position indicates the position of the holder when the paper feeding roller delivers the sheet. Then, when an abnormal condition occurs, the operation of the sheet feeding device is stopped. In this case, for example, the user pulls out the sheet stacking cassette (receiving portion) from the housing and tries to remove the sheets above the holder. However, since the biasing member biases the sheets toward the paper feed roller, it becomes difficult to smoothly pull out the sheet stacking cassette from the housing.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet feeding apparatus and an image forming apparatus in which a storage section can be smoothly pulled out from a housing.

According to one aspect of the present invention, a sheet feeding device includes a housing, a storage section, a placement section, a delivery section, a support section, a drive source, a position detection section, a determination section, a control and a part. The storage unit is detachable from the housing and can store a sheet. The stacking portion has a sheet stored in the storage portion mounted thereon, and is capable of changing an inclination angle with respect to the storage portion. The delivery unit delivers the stored sheet to the outside of the storage unit. The support section supports the delivery section and is movable in an approaching direction toward a predetermined position and a separation direction away from the predetermined position. The driving source is capable of moving the support portion in the approaching direction and the separating direction. The position detection section detects that the support section has reached the predetermined position. The determination unit determines whether or not an abnormal state indicating that the support unit cannot reach the predetermined position has occurred. The control section controls the drive source based on the determination result of the determination section. The predetermined position indicates the position of the support section when the delivery section delivers the stored sheet.

According to another aspect of the present invention, an image forming apparatus includes the above sheet feeding device.

According to the present invention, it is possible to smoothly pull out the accommodating portion from the housing.

1 is a schematic cross-sectional view of an image forming apparatus according to a first embodiment of the invention; FIG. FIG. 4 is a schematic cross-sectional view showing a state in which the cassette is accommodated in the housing; (a) is a perspective view of the pickup roller as seen from the outside of the cassette. (b) is a perspective view of the pickup roller as seen from below in the vertical direction. (a) It is the perspective view which looked at the cassette from the upstream of the delivery direction. (b) It is a partially enlarged view of the cassette. 3 is a block diagram of a sheet feeding device; FIG. 4 is a flow chart showing the operation of the control device of the first embodiment; FIG. FIG. 9 is a flow chart showing the operation of the control device of the second embodiment; FIG. 11 is a flow chart showing the operation of the control device of the third embodiment; FIG. 11 is a flow chart showing the operation of the control device of the fourth embodiment;

An embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

[First embodiment]
An image forming apparatus 100 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing an image forming apparatus 100. As shown in FIG.

As shown in FIG. 1, the image forming apparatus 100 includes a transport section 1, an input section 2, a reading section 3, a sheet feeding device 4, a sheet feeding roller 5, a retard roller 6, and a transport roller 7. , an image forming unit 8 , a discharge roller 9 , and a housing 10 .

The conveying unit 1 conveys a sheet having an image to be read toward the reading unit 3 . The reading unit 3 scans the sheet to obtain image data. The reading unit 3 includes, for example, a light emitting unit such as an LED (Light Emitting Diode) and an imaging unit such as an image sensor. The reading unit 3 scans an image formed on a sheet using a light emitting unit and an imaging unit. The sheet is, for example, plain paper, copy paper, recycled paper, thin paper, thick paper, glossy paper, or OHP (Overhead Projector) paper.

The input unit 2 includes a display unit 2a and an operation key group 2b. Input unit 2 receives an instruction from a user to image forming apparatus 100 . The display unit 2a functions as, for example, a touch panel.

The sheet feeding device 4 has a cassette 41 and a pickup roller 42 .

The cassette 41 is an example of a container according to the invention. Cassette 41 includes a bottom portion 41a and sidewall portions 41b. The bottom portion 41a has a plate shape. The side wall portion 41b extends along the substantially vertical direction V from the bottom portion 41a. Moreover, the side wall part 41b is formed in a substantially rectangular shape when viewed from above in the vertical direction V, for example. The side wall portion 41b forms an accommodation space 41c that is laterally closed on the bottom portion 41a.

The cassette 41 can accommodate sheets. Specifically, sheets can be stored in the storage space 41c of the cassette 41 . Sheets accommodated in the cassette 41 are referred to as accommodated sheets T. As shown in FIG. The pick-up roller 42 is an example of a delivery section according to the present invention. The pickup roller 42 sends out the accommodated sheet T to the outside of the cassette 41 . The outside of the cassette 41 is shown outside the accommodation space 41c. In the first embodiment, the pickup roller 42 sends out the storage sheet T toward the image forming section 8 .

The paper feed roller 5 is arranged downstream in the delivery direction X with respect to the pickup roller 42 . The retard roller 6 is arranged downstream in the delivery direction X with respect to the pickup roller 42 . The delivery direction X indicates the direction in which the pickup roller 42 delivers the stored sheet T. As shown in FIG. The paper feed roller 5 and the retard roller 6 rotate and convey the storage sheet T delivered by the pickup roller 42 while nipping it. The transport rollers 7 deliver the storage sheet T transported by the paper feed roller 5 and the retard roller 6 to the image forming section 8 .

The image forming section 8 forms an image on the storage sheet T. As shown in FIG. In a first embodiment, the image represents a toner image. The image forming section 8 includes a photosensitive drum, a charging section, an exposure section, a developing section, a transfer section, a cleaning section, a neutralization section, and a fixing section. An image is formed on the storage sheet T by the photosensitive drum, charging section, exposure section, development section, and transfer section. The cleaning section removes toner remaining on the surface of the photoreceptor drum. The static elimination unit eliminates residual charges on the surface of the photoreceptor drum. The storage sheet T on which the image is formed is sent toward the fixing section. The fixing section heats and presses the image to fix it on the storage sheet T. As shown in FIG.

The discharge roller 9 discharges the storage sheet T that has passed through the image forming section 8 to the outside of the housing 10 .

The housing 10 accommodates the image forming section 8 . Specifically, the housing 10 accommodates the sheet feeding device 4 , the paper feed roller 5 , the retard roller 6 , the transport roller 7 , the image forming section 8 , and the discharge roller 9 .

The cassette 41 is detachable from the housing 10 . In the first embodiment, the cassette 41 is accommodated in the housing 10 when the cassette 41 is inserted into the housing 10 . As a result, the cassette 41 is attached to the housing 10 . When the cassette 41 is attached to the housing 10, the pick-up roller 42 can feed out the storage sheet T. As shown in FIG.

When the cassette 41 is pulled out from the housing 10 after the cassette 41 is attached to the housing 10 , part or all of the cassette 41 is arranged outside the housing 10 . As a result, the cassette 41 can be replenished with the sheets T to be accommodated.

Next, the sheet feeding device 4 will be described with reference to FIGS. 2 to 4B. FIG. 2 is a schematic cross-sectional view showing a state in which the cassette 41 is accommodated in the housing 10. As shown in FIG.

As shown in FIG. 2, the sheet feeding device 4 further has a sheet stacking plate 43 . The sheet stacking plate 43 is an example of a stacking portion according to the present invention. The sheet stacking plate 43 has a plate shape. The sheet stacking plate 43 is housed in the cassette 41 . Accommodated sheets T are placed on the sheet stacking plate 43 . The sheet stacking plate 43 includes a first end 43a and a second end 43b. The first end portion 43 a is positioned substantially downward V<b>2 in the vertical direction V with respect to the cassette 41 . The second end 43b is positioned upstream in the delivery direction X with respect to the cassette 41. As shown in FIG.

The sheet feeding device 4 further has a lift plate 50 . The lift plate 50 is arranged below the sheet stacking plate 43 . The lift plate 50 is a rectangular plate member. A drive shaft 56 is fixed to one end of the lift plate 50 . The drive shaft 56 is rotatably supported by the cassette 41 . The other end of the lift plate 50 contacts the sheet stacking plate 43 from below V2 in the vertical direction V. As shown in FIG. A fan-shaped sector gear 57 is fixed to the end of the drive shaft 56 . Teeth are formed on the outer peripheral surface of the sector gear 57 . Driving force is transmitted to the sector gear 57 from a driving source 52 which will be described later. The drive source 52 is provided in the sheet feeding device 4 . The driving force transmitted from the driving source 52 of the sheet feeding device 4 rotates the sector gear 57, the driving shaft 56, and the lift plate 50 together. When the lift plate 50 rotates, the sheet stacking plate 43 rotates. The rotation of the lift plate 50 means that the other end of the lift plate 50 rotates around one end of the lift plate 50 . The rotation of the sheet stacking plate 43 means that the first end portion 43a rotates around the second end portion 43b. When the sheet stacking plate 43 rotates, the inclination angle θ of the sheet stacking plate 43 with respect to the cassette 41 is changed.

3A is a perspective view of the pickup roller 42 viewed from the outside of the cassette 41. FIG. In FIG. 3A, the upper portion of the cassette 41 (the upper portion of the accommodation space 41c) is closed by the ceiling portion 10a provided in the housing 10. As shown in FIG. 3B is a perspective view of the pickup roller 42 viewed from below V2 in the vertical direction V. FIG.

As shown in FIGS. 2 to 3B, the sheet feeding device 4 further has a holder 44 . The holder 44 is an example of a support section according to the present invention. A holder 44 supports the pickup roller 42 . Specifically, the holder 44 rotatably supports the pickup roller 42 . Also, the holder 44 rotatably supports the paper feed roller 5 .

The holder 44 includes a pair of facing portions 44a, and each of the pair of facing portions 44a is, for example, a plate-shaped member. The pair of opposing portions 44a are arranged along the rotation axis direction W with a space therebetween. A rotation axis direction W indicates the direction in which the rotation axis of the pickup roller 42 extends. The paper feed roller 5 and the pickup roller 42 are arranged between the pair of facing portions 44a. Each of the paper feed roller 5 and the pickup roller 42 is rotatably attached to a pair of facing portions 44a.

The holder 44 is supported by the housing 10 . The holder 44 is rotatably supported with respect to the housing 10 . The holder 44 has, for example, a rotating shaft 44b coaxial with the rotating shaft of the paper feed roller 5, and rotates around the rotating shaft 44b. The holder 44 can move in the approaching direction Y1 and the separating direction Y2 by rotating around the rotating shaft 44b. An approaching direction Y1 indicates a direction approaching a predetermined position. A separating direction Y2 indicates a direction separating from a predetermined position. The predetermined position indicates the position of the holder 44 when the pickup roller 42 feeds out the stored sheet T. As shown in FIG. In the first embodiment, the approaching direction Y1 indicates the direction in which the holder 44 rotates upward in the vertical direction V to the V1 side. The separation direction Y2 indicates the direction in which the holder 44 rotates downward in the vertical direction V to the V2 side.

As shown in FIG. 3B, the sheet feeding device 4 further has a position detection section 51 . The position detector 51 detects that the holder 44 has reached a predetermined position.

The position detection portion 51 includes a detection piece 51a, a detection housing 51b, and a detection portion 51c. The detection piece 51 a is fixed to the holder 44 and moves together with the holder 44 . The detection piece 51 a has an end portion 511 . When the holder 44 moves, the end 511 of the detection piece 51a approaches or separates from the detection housing 51b. The detection housing 51 b is fixed to the housing 10 . Specifically, the detection housing 51b is fixed to the housing 10 via the ceiling portion 10a. The detection housing 51b has a substantially U shape. The detection housing 51b has a pair of spacing portions 512 spaced apart from each other.

When the end portion 511 of the detection piece 51 a approaches the detection housing 51 b, the end portion 511 of the detection piece 51 a reaches between the pair of separation portions 512 . When the end portion 511 of the detection piece 51a is positioned between the pair of spacing portions 512, the holder 44 is positioned at the predetermined position.

The detection unit 51c is, for example, a PI (photo interrupter) sensor. The detection unit 51c is provided in the detection housing 51b. The detection unit 51 c has a light emitting unit provided in one of the pair of spaced units 512 . In addition, the detector 51c has a light receiving part in the other one of the pair of spaced parts 512 . Then, the end portion 511 of the detection piece 51a reaches between the pair of spaced portions 512 and blocks the light from the light emitting portion, so that the detection portion 51c detects the end portion 511 of the detection piece 51a. The detection of the end portion 511 of the detection piece 51a by the detection portion 51c indicates that the position detection portion 51 detects that the holder 44 has reached a predetermined position. Note that the detection unit 51c is not limited to the detection unit 51c of the first embodiment as long as it can detect that the holder 44 has reached a predetermined position. The detection unit 51c may be, for example, a touch sensor. In this case, when the end portion 511 of the detection piece 51a reaches between the pair of separation portions 512, it contacts the detection portion 51c, which is a touch sensor. As a result, the detection portion 51c detects the end portion 511 of the detection piece 51a.

4(a) is a perspective view of the cassette 41 viewed from the downstream in the delivery direction X. FIG. 4B is a partially enlarged view of the cassette 41. FIG.

As shown in FIGS. 4A and 4B, the sheet feeding device 4 further has a first gear 45, a second gear 46, and a third gear 48. As shown in FIGS.

The first gear 45 and the third gear 48 are rotatably supported by the cassette 41 . The first gear 45 rotates around a first shaft 45a. The third gear 48 rotates around the third shaft 48a. Each of the first gear 45 and the third gear 48 has a substantially cylindrical shape. A plurality of teeth are formed on the outer peripheral surface of the first gear 45 and the outer peripheral surface of the third gear 48 . The first gear 45 and the third gear 48 mesh with each other. The third gear 48 further meshes with the sector gear 57 .

The second gear 46 is rotatably supported by the housing 10 . The second gear 46 rotates around a second shaft 46a. The second axis 46a is parallel to the first axis 45a. The second gear 46 has a substantially cylindrical shape. A plurality of teeth are formed on the outer peripheral surface of the second gear 46 .

When the cassette 41 is attached to the housing 10 , the second gear 46 meshes with the first gear 45 . Specifically, the teeth of the first gear 45 mesh with the teeth of the second gear 46 . Therefore, when the second gear 46 rotates with the cassette 41 attached to the housing 10 , the first gear 45 , the third gear 48 and the sector gear 57 rotate together with the second gear 46 .

As shown in FIGS. 2, 4(a), and 4(b), the first gear 45 is connected to the seat via the third gear 48, the sector gear 57, the drive shaft 56, and the lift plate 50. It is connected to the stacking plate 43 . When the first gear 45 meshes with the second gear 46 and rotates, the sheet stacking plate 43 rotates.

When the second gear 46 rotates in the first direction C<b>1 with the cassette 41 attached to the housing 10 , each of the first gear 45 , the third gear 48 , and the sector gear 57 follows the second gear 46 . to rotate. In this case, when the cassette 41 is attached to the housing 10 and the second gear 46 rotates in the first direction C1, the sector gear 57 rotates in the first driven direction D1. When the sector gear 57 rotates in the first driven direction D1, the other end of the lift plate 50 rotates upward in the vertical direction V toward the V1 side with the one end of the lift plate 50 as the center. Therefore, when the sector gear 57 rotates in the first driven direction D1, the inclination angle θ of the sheet stacking plate 43 increases. The increase in the inclination angle θ of the sheet stacking plate 43 means that the first end portion 43a rotates upward in the vertical direction V1. As the inclination angle θ of the sheet stacking plate 43 increases, the accommodated sheets T come into contact with the pickup roller 42 . Then, the sheet stacking plate 43 presses the pick-up roller 42 upward in the vertical direction V1 via the stored sheets T. As shown in FIG. As a result, the holder 44 moves in the approach direction Y1. The pressure from the sheet stacking plate 43 allows the holder 44 to reach the predetermined position. Note that the second gear 46 rotates together with the motor of the drive source 52 . Therefore, rotation of the second gear 46 in the first direction C1 indicates rotation of the motor included in the drive source 52 in the first direction C1.

When the second gear 46 rotates in the second direction C<b>2 with the cassette 41 attached to the housing 10 , each of the first gear 45 , the third gear 48 , and the sector gear 57 follows the second gear 46 . to rotate. In this case, when the cassette 41 is attached to the housing 10 and the second gear 46 rotates in the second direction C2, the sector gear 57 rotates in the second driven direction D2. When the sector gear 57 rotates in the second driven direction D2, the other end of the lift plate 50 rotates downward in the vertical direction V toward the V2 side with the one end of the lift plate 50 as the center. Therefore, when the sector gear 57 rotates in the second driven direction D2, the inclination angle θ of the sheet stacking plate 43 decreases. The decrease in the inclination angle θ of the sheet stacking plate 43 means that the first end portion 43a rotates downward in the vertical direction V V2. of the sheet stacking plate 43 decreases, the cassette 41 moves in the separating direction Y2. As a result, the accommodation sheet T is separated from the pickup roller 42 . The second direction C2 is a direction opposite to the first direction C1. The second driven direction D2 is opposite to the first driven direction D1. The rotation of the second gear 46 in the second direction C2 means that the motor included in the drive source 52 rotates in the second direction C2.

A long hole 47 is formed in the cassette 41 . The elongated hole 47 extends toward the upstream side in the delivery direction X in a direction inclined upward from the horizontal direction. The slot 47 has a first slot end 47a and a second slot end 47b. The second elongated hole end 47b is positioned farther away from the first shaft 45a of the first gear 45 than the first elongated hole end 47a. The second elongated hole end 47b is positioned upstream in the delivery direction X from the first elongated hole end 47a.

When the second gear 46 rotates, the first gear 45 rotates while moving along the direction in which the long hole 47 extends.

The first gear 45 has a protruding portion 45b inserted through the long hole 47 . The protrusion 45 b extends along the first shaft 45 a of the first gear 45 . The protruding portion 45b is inserted into the long hole 47. As shown in FIG. The projecting portion 45b slides in the long hole 47. As shown in FIG. The protrusion 45b slides between the first slotted end 47a and the second slotted end 47b. When the projecting portion 45b slides along the elongated hole 47, the distance E between the first gear 45 and the second gear 46 in the meshing direction increases or decreases. A distance E in the meshing direction between the first gear 45 and the second gear 46 indicates a distance E between the first shaft 45 a of the first gear 45 and the second shaft 46 a of the second gear 46 .

When the cassette 41 is attached to the housing 10 and the projecting portion 45b is positioned at the first elongated hole end portion 47a, the first shaft 45a of the first gear 45 and the second shaft 46a of the second gear 46 are aligned. The distance E between is maximized. On the other hand, when the cassette 41 is attached to the housing 10 and the projecting portion 45b is positioned at the second elongated hole end portion 47b, the distance E is minimized.

When the second gear 46 rotates in the first direction C1 with the cassette 41 attached to the housing 10, the pressure received from the second gear 46 and the weight of the second gear 46 cause the projecting portion 45b to extend to the first length. It goes from the hole end 47a to the second elongated hole end 47b. As a result, distance E decreases. As the distance E decreases, the engagement between the teeth of the first gear 45 and the teeth of the second gear 46 deepens. On the other hand, when the second gear 46 rotates in the second direction C2 with the cassette 41 attached to the housing 10, the pressure received from the second gear 46 pushes the protruding portion 45b into the second long hole end portion 47b. toward the first slot end 47a. As a result, the distance E increases. As the distance E increases, the engagement between the teeth of the first gear 45 and the teeth of the second gear 46 becomes shallower.

The reason for changing the distance E is that when the cassette 41 is inserted into the housing 10, even if the tip of the tooth of the first gear 45 contacts the tip of the tooth of the second gear 46, the first gear 45 is kept longer. This is to escape along the hole 47 and prevent the teeth of the first gear 45 and the teeth of the second gear 46 from being damaged. The fact that the first gear 45 escapes along the long hole 47 means that the projecting portion 45b slides along the long hole 47 so that the distance E increases.

As described above with reference to FIGS. 2, 4(a), and 4(b), when the second gear 46 rotates in the second direction C2, the distance E increases. Therefore, for example, when the accommodation sheet T enters the upper part of the holder 44 and an abnormal state occurs, when the second gear 46 is rotated in the second direction C2, the teeth of the first gear 45 and the teeth of the second gear 46 are aligned. can be disengaged. As a result, even if a jam occurs in the holder 44, the cassette 41 can be smoothly pulled out from the housing 10.例文帳に追加

An abnormal state indicates a state in which the holder 44 cannot reach a predetermined position. Specifically, the abnormal state indicates a state in which the holder 44 cannot reach a predetermined position because the storage sheet T is in the upper part of the holder 44 and the storage sheet T is an obstacle.

Next, the sheet feeding device 4 will be further described with reference to FIG. FIG. 5 is a block diagram of the sheet feeding device 4. As shown in FIG.

As shown in FIG. 5 , the sheet feeding device 4 further includes a drive source 52 , a current detection section 53 , a storage section 54 and a control device 55 in addition to the position detection section 51 .

The driving source 52 can move the holder 44 in the approaching direction Y1 and the separating direction Y2. Drive source 52 rotates each of pickup roller 42 and second gear 46 . Further, the drive source 52 can rotate the first gear 45 , the third gear 48 and the sector gear 57 following the rotation of the second gear 46 . The drive source 52 is composed of, for example, a motor, gears, and a clutch. The motor is, for example, a reversible stepping motor. In the first embodiment, the motor of the drive source 52 is supplied with current to drive. The current detector 53 detects current flowing through the drive source 52 . In the first embodiment, the current detector 53 detects current flowing through the motor of the drive source 52 .

Storage unit 54 includes a storage device. The storage device includes a main storage device (eg, semiconductor memory) such as ROM (Read Only Memory) and RAM (Random Access Memory), and may further include an auxiliary storage device (eg, hard disk drive). The main memory and/or auxiliary memory store various computer programs executed by the controller 55 .

The control device 55 includes processors such as a CPU (Central Processing Unit) and an MPU (Micro Processing Unit). A control device 55 controls each element of the sheet feeding device 4 . Specifically, the processor of the control device 55 controls the position detection section 51, the drive source 52, the current detection section 53, and the storage section 54 by executing a computer program stored in the storage device. . Further, in the first embodiment, the control device 55 also controls each element of the image forming apparatus 100 .

The control device 55 has a control section 55a and a determination section 55b. Specifically, the processor of the control device 55 functions as a control section 55a and a determination section 55b by executing a computer program stored in a storage device.

Next, the operation of the control device 55 will be described with reference to FIG. FIG. 6 is a flowchart showing the operation of the control device 55 of the first embodiment.

As shown in FIG. 6, in step S10, when the cassette 41 is inserted into the housing 10 and the cassette 41 is attached to the housing 10, a detecting member (not shown) detects that the cassette 41 has been attached to the housing 10. detect. When the detection member detects that the cassette 41 is attached to the housing 10, the controller 55a receives a signal from the detection member. When the controller 55a receives the signal from the detection member, the controller 55a moves the sheet stacking plate 43 of the cassette 41 upward V1 in the vertical direction V and starts the process of moving the holder 44 in the approaching direction Y1. That is, when the detection member detects that the cassette 41 is attached to the housing 10, the controller 55a controls the drive source 52 so that the holder 44 moves in the approach direction Y1. A detection member is provided in the sheet feeding device 4 . A detection member is a touch sensor, for example.

In step S20, the controller 55a controls the drive source 52 so that the second gear 46 rotates in the first direction C1 with the cassette 41 attached to the housing 10. FIG.

In step S30, the position detector 51 detects whether the holder 44 has reached a predetermined position. If the position detection unit 51 has not detected that the holder 44 has reached the predetermined position (No in step S30), the process proceeds to step S40. If the position detection unit 51 detects that the holder 44 has reached the predetermined position (Yes in step S30), the process ends.

In step S40, the determination unit 55b determines whether a predetermined time has passed since the control unit 55a started driving the drive source 52 so that the second gear 46 rotates in the first direction C1. Note that the determination unit 55b has a function of a timer, and counts a predetermined time with the timer. For a predetermined period of time, for example, the driving source 52 is driven from a state in which the sheet stacking plate 43 is tilted substantially parallel to the bottom portion 41a of the cassette 41, the inclination angle θ of the sheet stacking plate 43 is increased, and the holder is opened. The time required for 44 to reach a predetermined position is shown (see FIG. 2). The predetermined time is obtained, for example, by experiment. Information indicating the predetermined time is stored in the storage unit 54 in advance.

If the predetermined time has passed (Yes in step S40), the process proceeds to step S50. If the predetermined time has not elapsed (No in step S40), the process proceeds to step S30.

In step S50, the determination unit 55b determines that an abnormal state has occurred. Specifically, in the first case, the determination unit 55b determines that an abnormal state has occurred. In the first case, the holder 44 reaches the predetermined position after a predetermined time has elapsed since the controller 55a started driving the drive source 52 so that the second gear 46 rotates in the first direction C1. indicates the absence of

In step S60, when the determination unit 55b determines that an abnormal situation has occurred, the control unit 55a controls the drive source 52 so that the second gear 46 rotates in the second direction C2. Specifically, when the determination unit 55b determines that an abnormal situation has occurred, the control unit 55a controls the drive source 52 so that the second gear 46 stops rotating. Then, the controller 55a controls the drive source 52 so that the second gear 46 rotates in the second direction C2. In this case, the controller 55a controls the driving source 52 so that the second gear 46 rotates in the second direction C2 by a predetermined number of rotations. In this case, the control unit 55a may control the driving source 52 so that the second gear 46 rotates in the second direction C2 at a rotation speed higher than a predetermined rotation speed.

The predetermined number of rotations is, for example, the number of rotations of the second gear 46 required to slide the projection 45b of the first gear 45 from the second slot end 47b of the slot 47 to the first slot end 47a. number (see FIG. 4(b)). The predetermined number of revolutions is obtained, for example, by experiment. Information indicating the predetermined number of rotations is stored in the storage unit 54 in advance. When the second gear 46 rotates in the second direction C2 by a predetermined number of rotations, the process ends.

In step S60, the controller 55a may control the drive source 52 so that the second gear 46 rotates in the second direction C2 for a predetermined rotation time. Further, in step S60, the control unit 55a may control the driving source 52 so that the second gear 46 rotates in the second direction C2 for a rotation time longer than the predetermined rotation time. The predetermined rotation time is, for example, the rotation of the second gear 46 required to slide the projection 45b of the first gear 45 from the second slot end 47b of the slot 47 to the first slot end 47a. indicate the time. The predetermined rotation time is obtained, for example, by experiment. Information indicating the predetermined rotation time is stored in advance in the storage unit 54. The predetermined rotation time also takes into consideration the rotation speed of the second gear 46 when the second gear 46 rotates in the second direction C2. is required.

In step S70, the control unit 55a controls the display unit 2a so as to display information (abnormality notification screen) indicating that an abnormal state has occurred on the display unit 2a. As a result, the process ends. By displaying the abnormality notification screen on the display unit 2a, the user can recognize that an abnormality has occurred.

As described above with reference to FIG. 6, the control unit 55a controls the drive source 52 based on the determination result of the determination unit 55b. Therefore, when the determination unit 55b determines that an abnormal state has occurred, the control unit 55a can control the drive source 52 so that the second gear 46 rotates in the second direction C2. When the second gear 46 rotates in the second direction C2, the teeth of the first gear 45 and the teeth of the second gear 46 can be disengaged. As a result, even if an abnormal condition occurs, the cassette 41 can be smoothly pulled out from the housing 10 .

In the first case, the determination unit 55b determines that an abnormal state has occurred. Therefore, the time required by the determination unit 55b to determine whether an abnormal state has occurred can be kept within the predetermined time. As a result, the determination unit 55b can quickly determine whether an abnormal state has occurred.

[Second embodiment]
Next, an image forming apparatus 100 according to a second embodiment of the invention will be described with reference to FIG. FIG. 7 is a flowchart showing the operation of the control device 55 of the second embodiment.

The second embodiment differs from the first embodiment in that the determination unit 55b determines whether or not an abnormal state has occurred based on the detection result of the current detection unit 53. FIG. Differences from the first embodiment will be mainly described below.

In step S30, if the position detection unit 51 has not detected that the holder 44 has reached the predetermined position (No in step S30), the process proceeds to step S41.

In step S<b>41 , the current detector 53 detects the current flowing through the drive source 52 . If the current detected by the current detector 53 is greater than the predetermined value (Yes in step S41), the process proceeds to step S51. If the current detected by the current detector 53 is smaller than the predetermined value (No in step S41), the process proceeds to step S30. The predetermined value indicates, for example, a value of current that is greater than the maximum value of the current that flows through the drive source 52 when the holder 44 is moved in the approach direction Y1 and reaches a predetermined position. The predetermined value is obtained by experiments, for example. Information indicating the predetermined value is stored in the storage unit 54 in advance.

In step S51, the determination unit 55b determines that an abnormal state has occurred. Specifically, in the second case, the determination unit 55b determines that an abnormal state has occurred. In the second case, the controller 55a controls the drive source 52 to rotate the second gear 46 in the first direction C1. Indicates the case of detection. Then, the process moves to step S60.

As described above with reference to FIG. 7, in the second case, the determination unit 55b determines that an abnormal state has occurred. Therefore, it is possible to suppress the overcurrent from flowing through the drive source 52 and suppress the torque of the drive source 52 from becoming excessively large. As a result, it is possible to prevent the drive source 52 from being overloaded.

[Third Embodiment]
Next, an image forming apparatus 100 according to a third embodiment of the invention will be described with reference to FIG. FIG. 8 is a flowchart showing the operation of the control device 55 of the third embodiment.

In the third embodiment, the determination unit 55b determines whether or not an abnormal state has occurred based on the drive time of the drive source 52 and the detection result of the current detection unit 53, which is the same as in the first embodiment. , and is different from the second embodiment. Differences from the first embodiment and the second embodiment will be mainly described below.

In step S30, if the position detection unit 51 has not detected that the holder 44 has reached the predetermined position (No in step S30), the process proceeds to step S40.

In step S40, if the predetermined time has not elapsed (No in step S40), the process proceeds to step S41. If the predetermined time has passed (Yes in step S40), the process proceeds to step S52.

In step S41, if the current detected by the current detector 53 is greater than the predetermined value (Yes in step S41), the process proceeds to step S52. If the current detected by the current detector 53 is smaller than the predetermined value (No in step S41), the process proceeds to step S30.

In step S52, the determination unit 55b determines that an abnormal state has occurred. Specifically, in the first case or the second case, the determination unit 55b determines that an abnormal state has occurred.

As described above with reference to FIG. 8, the determination unit 55b determines that an abnormal state has occurred in the first case or the second case. Therefore, the determination unit 55b can quickly determine whether or not an abnormal state has occurred while suppressing overloading of the drive source 52 .

[Fourth Embodiment]
Next, an image forming apparatus 100 according to a fourth embodiment of the invention will be described with reference to FIG. FIG. 9 is a flow chart showing the operation of the control device 55 of the fourth embodiment.

In the fourth embodiment, the determination unit 55b determines whether or not an abnormal state has occurred based on the drive time of the drive source 52 and the detection result of the current detection unit 53. is the same as However, the requirements for the determination unit 55b to determine that an abnormal state has occurred are stricter than in the third embodiment. Differences from the first to third embodiments will be mainly described below.

In step S30, if the position detection unit 51 has not detected that the holder 44 has reached the predetermined position (No in step S30), the process proceeds to step S40.

In step S40, if the predetermined time has elapsed (Yes in step S40), the process proceeds to step S41. If the predetermined time has not elapsed (No in step S40), the process proceeds to step S30.

In step S41, if the current detected by the current detector 53 is greater than the predetermined value (Yes in step S41), the process proceeds to step S53. If the current detected by the current detector 53 is smaller than the predetermined value (No in step S41), the process proceeds to step S30.

In step S53, the determination unit 55b determines that an abnormal state has occurred. Specifically, the determination unit 55b determines that an abnormal state has occurred in the first case and the second case.

As described above with reference to FIG. 9, the determination unit 55b determines that an abnormal state has occurred in the first case and the second case. Therefore, it is possible to set a stricter criterion for the judgment unit 55b to judge that an abnormal state has occurred. As a result, the sheet feeding device 4 can smoothly perform the process of feeding the accommodated sheets T. As shown in FIG.

The embodiments of the present invention have been described above with reference to the drawings (FIGS. 1 to 9). However, the present invention is not limited to the above embodiments, and can be implemented in various aspects without departing from the scope of the invention (eg, (1) to (3)). Various inventions can be formed by appropriately combining the plurality of constituent elements disclosed in the above embodiments. For example, some components may be omitted from all components shown in the embodiments. In order to facilitate understanding, the drawings mainly show each component schematically, and the number of each component shown in the figure may differ from the actual number due to the convenience of drawing. Also, each component shown in the above embodiment is an example and is not particularly limited, and various modifications are possible within a range that does not substantially deviate from the effects of the present invention.

(1) As shown in FIG. 4B, in the first embodiment, the distance E changes as the first gear 45 moves. However, the invention is not so limited. The distance E may change as the second gear 46 moves. Moreover, the distance E may change by moving both the first gear 45 and the second gear 46 .

(2) In the first embodiment, the sheet feeding device 4 is provided in the image forming apparatus 100 . However, the invention is not so limited. The sheet feeding device 4 may not be provided in the image forming apparatus 100 but may be attached to the image forming apparatus 100 afterward. In other words, the sheet feeding device 4 only needs to have a function of feeding the storage sheet T to the image forming section 8 .

(3) In the first embodiment, the image forming section 8 forms black and white toner images. However, the invention is not so limited. The image forming section 8 may form a color toner image using toners of a plurality of colors. In this case, the image forming section 8 may be a tandem device using a plurality of photosensitive drums, or may be a rotary device using a single photosensitive drum. Further, the image forming section 8 may have nozzles and eject ink from the nozzles to form an image on the storage sheet T. FIG. In this case, the image represents an ink image.

INDUSTRIAL APPLICABILITY The present invention can be used in the fields of sheet feeding apparatuses and image forming apparatuses.

4 sheet feeding device 8 image forming unit 10 housing 41 cassette (accommodating unit)
42 Pick-up roller (sending part)
43 sheet loading plate (placing section)
44 holder (supporting part)
45 1st gear 45a 1st shaft 45b Protruding portion 46 2nd gear 46a 2nd shaft 47 Long hole 51 Position detection portion 52 Drive source 53 Current detection portion 55a Control portion 55b Judgment portion 100 Image forming apparatus C1 First direction C2 Second Direction E Distance T Accommodating sheet Y1 Approach direction Y2 Separation direction θ Angle of inclination

Claims (9)

a cassette that is detachable from the housing and capable of containing sheets;
a placement portion on which a stored sheet, which is a sheet stored in the cassette , is placed and whose inclination angle with respect to the cassette can be changed;
a delivery unit for delivering the storage sheet to the outside of the cassette in a delivery direction ;
a support unit that supports the delivery unit and is rotatably supported by the housing in an approaching direction toward a predetermined position and in a separating direction away from the predetermined position;
a driving source capable of moving the support portion in the approaching direction and the separating direction;
a position detection unit that detects that the support has reached the predetermined position;
a determination unit that determines whether an abnormal state indicating that the support unit cannot reach the predetermined position has occurred;
a control unit that controls the drive source based on the determination result of the determination unit;
The predetermined position indicates a position of the support portion when the delivery portion delivers the storage sheet,
The cassette is
a first gear rotatably supported on the cassette by a first shaft ;
A long hole that supports the first shaft and extends from a second long hole end on the downstream side in the delivery direction to a first long hole end on the upstream side in the delivery direction from the second long hole end When
has
The housing has a second gear rotatably supported by the housing by the drive source ,
The first gear is such that the first shaft is slidable in the long hole,
the first gear is movable with respect to the cassette by sliding the first shaft through the long hole;
the driving source includes a motor rotatable in a first direction and a second direction opposite to the first direction;
By rotating the motor in the first direction, the second gear also rotates in the first direction in which the engagement with the first gear becomes deeper, and the support portion is movable in the approaching direction,
By rotating the motor in the second direction, the second gear also rotates in the second direction in which the engagement with the first gear is shallow, and the support portion is movable in the separating direction,
When the determination unit determines that the abnormal state has occurred, the control unit controls the motor of the drive source rotating in the first direction to rotate in the second direction,
When the judging section judges that the abnormal state has occurred due to the occurrence of a jam in the cassette, the control section controls the motor to rotate the second gear rotating in the first direction. stopping the rotation, further rotating the second gear in the second direction by a predetermined number of rotations, and then stopping;
The predetermined number of rotations is the number of rotations of the second gear required to slide the first shaft of the first gear from the end of the second elongated hole to the end of the first elongated hole. the law of nature,
when the first shaft of the first gear is located at the end of the first elongated hole, the engagement of the first gear with the second gear becomes deep;
The sheet feeding device according to claim 1, wherein when the first shaft of the first gear is located at the end of the second elongated hole, the engagement between the first gear and the second gear becomes shallow . a third gear;
a sector gear that meshes with the third gear and changes the inclination angle of the mounting section;
The second gear meshes with the first gear, and the movement of the first gear with respect to the cassette causes depth of meshing with the first gear,
the first gear engages the sector gear via the third gear when moving toward and away from the second gear in response to rotation of the second gear;
The sheet feeding device according to claim 1. If the support portion has not reached the predetermined position after a predetermined time has passed since the control unit started driving the drive source so that the motor rotates in the first direction, the abnormality occurs. 3. The sheet feeding apparatus according to claim 1, wherein said determination unit determines that a state has occurred. further comprising a current detection unit that detects a current flowing through the motor of the drive source;
3. The sheet feeding apparatus according to claim 1, wherein said determination unit determines that said abnormal state has occurred when said current detection unit detects a current greater than a predetermined value. further comprising a current detection unit that detects a current flowing through the motor of the drive source;
When the support portion has not reached the predetermined position after a predetermined time has passed since the control unit started driving the drive source so that the motor rotates in the first direction, or 3. The sheet feeding apparatus according to claim 1, wherein said determination unit determines that said abnormal state has occurred when said current detection unit detects a current greater than a predetermined value. further comprising a current detection unit that detects a current flowing through the motor of the drive source;
The support portion has not reached the predetermined position after a predetermined time has elapsed since the control unit started driving the drive source so that the motor rotates in the first direction, and 3. The sheet feeding apparatus according to claim 1, wherein said determination unit determines that said abnormal state has occurred when said current detection unit detects a current greater than a predetermined value. The sheet feeding apparatus according to any one of claims 1 to 6, wherein the feeding section feeds the accommodated sheet toward an image forming section that forms an image on the sheet. further comprising a detection member that detects that the cassette is attached to the housing;
8. The apparatus according to any one of claims 1 to 7, wherein when the detection member detects that the cassette is mounted in the housing, the control section controls the drive source so that the support section moves in the approaching direction. The sheet feeding device according to any one of items 1 and 2. An image forming apparatus comprising: the sheet feeding device according to any one of claims 1 to 8; and the housing.

Images