JP2023112772A - Conveyance device and image formation device - Google Patents

Abstract

To provide a sheet conveyance device having a planetary gear which reduces force required for dissolving sheet jamming.SOLUTION: A conveyance device for conveying a recording material has: an input member having an internal tooth gear part; a sun member having a sun gear part; a carrier member having a support shaft; a planetary gear which is engaged with the sun gear part and the internal tooth gear part, and is rotatably supported on a support shaft; a roller which is driven by the carrier member, and conveys a recording material; and a regulation member which is movable between a regulation position where rotation of the sun member is regulated, and a retreat position that is retreated from the regulation position. When the input member is rotated in a state where the regulation member is at the regulation position, the planetary gear revolves along the sun gear part, and thereby the carrier member having the support shaft, and the roller are rotated. When sheet jamming is dissolved, the regulation member is moved to the retreat position.SELECTED DRAWING: Figure 7

Description

The present invention relates to a conveying device for conveying a recording material and an image forming apparatus using the same.

2. Description of the Related Art A sheet jam (so-called paper jam) may occur in a conveying device for conveying a recording material (sheet) and an image forming apparatus using the same. When a sheet jam occurs, it is necessary for the user to pull the jammed sheet inside the image forming apparatus to remove the sheet. The greater force required to remove the sheet increases the user's load.

Japanese Patent Laid-Open No. 2002-200001 describes a configuration in which, when a jam occurs, the user operates an operation lever and then turns an operation dial to clear the jam.

Japanese Patent Application Laid-Open No. 2002-200001 describes a configuration in which the pressure of the heating unit against the pressure roller is released when a jam occurs.

JP 2012-144309 A JP 2010-139732 A

SUMMARY OF THE INVENTION An object of the present invention is to reduce the force required to clear a sheet jam in a sheet conveying device having planetary gears.

One of the inventions according to the present application is as follows.

A conveying device for conveying a recording material,
an input member having an internal gear portion;
a sun member having a sun gear portion;
a carrier member having a support shaft;
a planetary gear meshing with the sun gear portion and the internal gear portion and rotatably supported by the support shaft;
a roller driven by the carrier member for conveying the recording material;
a regulating position for regulating rotation of the sun member; a regulating member movable to a retracted position retracted from the regulating position;
a moving member that moves the regulating member between the regulating position and the retracted position;
a recording material detection unit that detects the recording material;
has
When the input member rotates while the regulating member is in the regulating position, the planetary gear revolves around the sun gear portion, thereby rotating the carrier member having the support shaft and the roller. ,
The conveying device, wherein the moving member moves the regulating member to the retracted position when the recording material detecting unit detects an abnormality in conveying the recording material.

One of the inventions according to the present application is as follows.

A conveying device for conveying a recording material,
an input member having an internal gear portion;
a sun member having a sun gear portion;
a carrier member having a support shaft;
a planetary gear meshing with the sun gear portion and the internal gear portion and rotatably supported by the support shaft;
a roller driven by the carrier member for conveying the recording material;
a regulating position for regulating rotation of the sun member; a regulating member movable to a retracted position retracted from the regulating position;
a moving member that moves the regulating member between the regulating position and the retracted position;
an openable/closable opening/closing member that covers a conveying path along which the recording material is conveyed;
has
When the input member rotates while the regulating member is in the regulating position, the planetary gear revolves around the sun gear portion, thereby rotating the carrier member having the support shaft and the roller. ,
A conveying apparatus, wherein when the opening/closing member is opened so as to expose the conveying path, the regulating member moves to the retracted position in conjunction with movement of the opening/closing member.

One of the inventions according to the present application is as follows.

A conveying device for conveying a recording material,
an input member having an internal gear portion;
a sun member having a sun gear portion;
a carrier member having a support shaft;
a planetary gear meshing with the sun gear portion and the internal gear portion and rotatably supported by the support shaft;
a roller driven by the carrier member for conveying the recording material;
a regulating position for regulating rotation of the sun member; a regulating member movable to a retracted position retracted from the regulating position;
a moving member that moves the regulating member between the regulating position and the retracted position;
has
When the input member rotates while the regulating member is in the regulating position, the planetary gear revolves around the sun gear portion, thereby rotating the carrier member having the support shaft and the roller. ,
When the regulating member at the regulating position receives a force of a predetermined magnitude or more from the sun member, the regulating member retreats from the regulating position.
A conveying device characterized by:

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the force required to clear a sheet jam in a sheet conveying apparatus having planetary gears.

1 is a cross-sectional view of an image forming apparatus; FIG. 1 is a cross-sectional view of an image forming apparatus in which double-sided printing is being performed; FIG. 1 is a cross-sectional view of an image forming apparatus in which double-sided printing is being performed; FIG. 4A and 4B are diagrams illustrating a driving mechanism of a refeeding roller according to the first embodiment; FIG. FIG. 2 is an explanatory diagram of a planetary gear unit according to Example 1; 3 is a perspective view of a planetary gear unit and a solenoid according to Example 1. FIG. FIG. 10 is a diagram for explaining the operation of the planetary gear unit when the sheet jam is cleared; 4 is a cross-sectional view of the image forming apparatus when a sheet jam is cleared; FIG. FIG. 5 is a block diagram showing sheet jam clearing according to the first embodiment; FIG. 5 is a block diagram showing sheet jam clearing according to the first embodiment; FIG. 10 is a diagram showing operations of a door and a solenoid according to the second embodiment; FIG. 11 is a diagram showing the relationship between a planetary sun gear and a solenoid according to Example 3; FIG. 11 is a diagram showing the relationship between a planetary sun gear and a solenoid according to Example 3;

(Example 1)
Preferred embodiments of the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, and relative positions of components described in the following embodiments should be appropriately changed according to the configuration of the device to which the present invention is applied and various conditions. Therefore, it is not intended to limit the scope of the present invention only to them unless specifically stated otherwise.

<Image forming apparatus>
An image forming apparatus 100 according to this embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view showing the structure of an image forming apparatus 100 according to this embodiment. The image forming apparatus 100 in this embodiment is a laser beam printer that forms an image on a sheet S as a recording material using an electrophotographic method. The image forming apparatus 100 is not limited to a laser beam printer, and may be a copying machine, a so-called LED printer using light emitting diodes, an inkjet printer, or the like. Examples of materials for the sheet S include paper, resin, and cloth.

The image forming apparatus 100 has an apparatus main body 100A. Inside the apparatus main body 100A, there are provided a sheet feeding tray 110 for storing sheets S, a sheet feeding roller 2a, a driven sheet feeding roller 2b, an intermediate conveying roller 9a, a driven intermediate roller 9b, a conveying roller 3a, and a driven conveying roller 3b. is provided. The driven paper feed roller 2b, the driven intermediate roller 9b, and the driven transport roller 3b are driven by corresponding rollers. Further, a control unit 150 is provided inside the apparatus main body 100A.

Further, inside the apparatus main body 100A, a photosensitive drum 4 and a scanner 120 as an exposure device for exposing the surface of the photosensitive drum 4 are provided. In this embodiment, the photosensitive drum 4 is provided in a cartridge P detachably attached to the apparatus main body 100A. The cartridge P also includes a charging device that charges the photosensitive drum 4, toner as a developer, and a developing device that develops the electrostatic latent image formed on the photosensitive drum 4 using the toner.

A transfer roller 5 is provided so as to face the photosensitive drum 4 . A primary transfer portion is formed between the transfer roller 5 and the photosensitive drum 4 .

A sheet S set on a sheet feeding tray 110 is fed by a sheet feeding roller 2a and a driven sheet feeding roller 2b. The sheet S is conveyed to a primary transfer portion formed by the photosensitive drum 4 and the transfer roller 5 by the intermediate conveying roller 9a, the driven intermediate roller 9b, the conveying roller 3a, and the driven conveying roller 3b.

A scanner 120 irradiates a laser beam onto the photosensitive drum 4 charged by the charging device. As a result, an electrostatic latent image corresponding to image information is formed on the surface of the photosensitive drum 4 . The electrostatic latent image formed on the photosensitive drum 4 is developed as a toner image by a developing device. The toner image formed on the photosensitive drum 4 is transferred onto the sheet S by the transfer roller 5 . The photosensitive drum 4 and the transfer roller 5 function as an image forming section that forms an image on the sheet S. As shown in FIG. Further, the scanner 120 and the developing device can also be said to be part of the image forming section.

A fixing device including a pressure roller 6a and a heater unit 6b containing a heater is provided inside the apparatus main body 100A. The toner image transferred to the sheet S is fixed on the sheet S by the pressure roller 6a and the heater unit 6b.

A discharge roller 7a, a first facing roller 7b, and a second facing roller 7c are provided inside the apparatus main body 100A. The first opposed roller 7b and the second opposed roller 7c are driven by the paper discharge roller 7a. A sheet stacking tray 1 on which sheets S discharged from the apparatus main body 100A are stacked is provided on the upper portion of the apparatus main body 100A.

The operation of forming an image on one side of the sheet S is called single-sided printing. When single-sided printing is executed, the sheet S that has passed through the fixing device is discharged onto the sheet stacking tray 1 by the discharge roller 7a and the first opposing roller 7b.

<Double-sided printing>
The operation of forming images on both sides of the sheet S is called double-sided printing. Double-sided printing for one sheet will be described with reference to FIG. FIG. 2 is a cross-sectional view of the image forming apparatus 100 performing double-sided printing.

A movable guide 10 is provided inside the apparatus main body 100A. The movable guide 10 is arranged on the downstream side of the fixing device with respect to the conveying direction of the sheet S by the fixing device. The movable guide 10 guides the sheet S to the discharge section formed by the discharge roller 7a and the first opposing roller 7b (see FIG. 1), and guides the sheet S to the discharge roller 7a and the second opposing roller 7b. 7c to a second position (see FIG. 2) leading to the reversal formed by 7c.

When double-sided printing is performed, the movable guide 10 is moved to the second position. The sheet S having an image formed on one side (front side) and having passed through the fixing device is guided by the movable guide 10 toward the discharge roller 7a and the second opposing roller 7c. After that, the sheet S is conveyed by the discharge roller 7a and the second opposing roller 7c.

A paper discharge sensor 22 is arranged downstream of the fixing device in the direction in which the sheet S is conveyed by the fixing device. As shown in FIG. 2, inside the apparatus main body 100A, there is a re-conveyance path (conveyance path) through which the sheet S having an image formed on one side (surface) passes when it is conveyed again toward the image forming section. path) 140 is provided. The re-conveying path 140 includes a first double-sided path 140a and a second double-sided path 140b. The re-feeding path 140 is provided with a re-feeding roller (roller) 8a and a driven re-feeding roller 8b.

When it is detected that the trailing edge of the sheet S has passed the sheet discharge sensor 22, the sheet discharge roller 7a rotates in the reverse direction, and the sheet S is conveyed toward the first double-sided path 140a. After that, the sheet S is conveyed to the second double-sided path 140b by the re-feeding roller 8a and the driven re-feeding roller 8b.

The sheet S reaches the conveying roller 3a via the second double-sided path 140b. After that, an image is formed on the other side (back side) of the sheet S in the same manner as when single-sided printing is executed. The sheet S is guided by a movable guide 10 to a sheet ejection portion formed by a sheet ejection roller 7 a and a first opposed roller 7 b and ejected onto the sheet stacking tray 1 .

Double-sided printing for a plurality of sheets will be described with reference to FIG. FIG. 3 is a cross-sectional view of the image forming apparatus 100 performing double-sided printing on a plurality of sheets S. As shown in FIG.

FIG. 3 shows a state in which two-sided printing is being performed on three sheets S. As shown in FIG. The three sheets S are referred to as a first sheet S1, a second sheet S2, and a third sheet S3 in the order in which the image forming operation is completed.

In order to increase the speed of double-sided printing, it is preferable to minimize the interval between the sheets S. On the other hand, the interval between the sheets S (the interval between the trailing edge of the first sheet S1 and the leading edge of the second sheet S2, the interval between the trailing edge of the second sheet S2 and the leading edge of the third sheet S3) is set to a certain length or longer. There is a need.

For example, when the re-feeding roller 8a is always rotated and the trailing edge of the first sheet S1 overlaps the leading edge of the second sheet S2, the leading edge of the second sheet S2 is not detected, and the transfer timing of the toner image is not detected. , the conveying timing of the second sheet S2 cannot be synchronized.

Therefore, in the image forming apparatus 100, rotation and stoppage of the refeeding roller 8a are switched so that the interval between the sheets S becomes a preferable length. Switching between rotation and stopping of the paper re-feeding roller 8a is controlled based on detection results of the conveying sensor 21 and paper re-feeding sensor 23. FIG. In the image forming apparatus 100 according to the present embodiment, when it is detected that the leading edge of the second sheet S2 reaches the refeeding sensor 23, the refeeding roller 8a stops rotating and the second sheet S2 stops. . When it is detected that the trailing edge of the first sheet S1 has passed the conveying sensor 21, the refeeding roller 8a starts to rotate, and the second sheet S2 is conveyed toward the conveying roller 3a.

As described above, the image forming apparatus 100 can convey the sheet S and form an image on the sheet S. FIG. In other words, the image forming apparatus 100 can be said to have a function as a conveying device (sheet conveying device) that conveys the sheet S. As shown in FIG. In other words, the image forming apparatus 100 has a conveying device having a function of conveying the sheet S and an image forming section having a function of forming an image on the sheet S. FIG.

<Driving Mechanism of Refeed Roller>
A drive mechanism for the re-feeding roller 8a will be described with reference to FIG. In this embodiment, the drive mechanism for the paper refeed roller 8a includes a planetary gear unit 31. As shown in FIG.

4 (FIGS. 4A and 4B) are diagrams showing the driving mechanism of the paper re-feeding roller 8a according to this embodiment. 4A is a view of the driving device viewed from one side of the image forming apparatus 100 with respect to the direction of the rotation axis of the refeeding roller 8a, and FIG. 4B is a view of the other side of the image forming apparatus 100. 1 is a view of the driving device seen from above; FIG.

An apparatus main body 100A of the image forming apparatus 100 is provided with a motor M as a drive source. The drive mechanism for the paper refeed roller 8a includes a paper refeed input gear 32 that rotates under the force of the motor M, a planetary gear unit 31, a paper refeed idler gear 33, and a paper refeed roller gear .

A solenoid 35 as a locking device is arranged near the planetary gear unit 31 . The solenoid 35 has a flapper (regulating member) 35a, a coil 35b, and a spring 35c as a biasing member that biases the flapper 35a. The coil 35b and the spring 35c function as a moving member that moves the flapper 35a between a restricted position and a retracted position, which will be described later.

The coil 35b is a magnetic field generating member that generates a magnetic field when supplied with electric power. The flapper 35a is magnetic and is moved by the magnetic field of the coil 35b. The image forming apparatus 100 has a power supply section (power supply) PS that supplies power to the coil 35 b of the solenoid 35 . The control unit 150 controls the power supply unit PS to control the operation of the coil 35b (supply of power to the solenoid 35). In the following description, "power is supplied to the solenoid 35" means "power is supplied to the coil 35b".

The paper refeed input gear 32 meshes with the planetary input gear 31 a of the planetary gear unit 31 . The planetary carrier gear 31b of the planetary gear unit 31 meshes with the refeeding idler gear 33. As shown in FIG. The paper refeed idler gear 33 is a step gear and meshes with the planetary carrier gear 31 b and the paper refeed roller gear 34 . The refeeding roller gear 34 is attached to the refeeding roller 8a.

A driving force is transmitted to the re-feeding input gear 32 from the motor M, which is a driving source. The motor M also transmits driving power to the fixing device, the photosensitive drum 4, and the like. Further, the motor M also transmits drive to the paper feed roller 2a, the intermediate transport roller 9a, the transport roller 3a, and the paper discharge roller 7a.

Since the paper refeed input gear 32 is meshed with the planetary input gear 31 a , the drive force is transmitted from the motor M to the planetary gear unit 31 . The driving force transmitted to the planetary gear unit 31 is transmitted to the re-feeding roller gear 34 via the re-feeding idler gear 33 . The re-feeding roller gear 34 is arranged coaxially with the re-feeding roller 8a and is connected to the re-feeding roller 8a. As the re-feeding roller gear 34 rotates, the re-feeding roller 8a rotates, and the sheet S is conveyed by the re-feeding roller 8a.

In this manner, the driving force of the motor M is transmitted to the re-feeding roller 8a via the re-feeding input gear 32, the planetary gear unit 31, the re-feeding idler gear 33, and the re-feeding roller gear .

As will be described later, rotation and stoppage of the paper refeed roller 8a are switched by using the planetary gear unit 31. FIG. In the image forming apparatus 100 according to the present embodiment, the paper re-feeding roller 8a and other members are driven by the motor M, and the paper re-feeding roller 8a can be stopped while the other members are being driven. In other words, according to the image forming apparatus 100 of the present embodiment, it is possible to share the drive source for driving the refeeding roller 8a and the drive source for driving other members. Further, it is not necessary to use a clutch such as an electromagnetic clutch for rotating and stopping the paper re-feeding roller 8a. As a result, the cost of the image forming apparatus 100 can be reduced.

<Planetary gear unit>
The planetary gear unit 31 will be explained using FIG. FIG. 5 is an explanatory diagram of the planetary gear unit 31. As shown in FIG. In FIG. 5, a cross section of the planetary gear unit 31 and the solenoid 35 are shown.

The planetary gear unit 31 has a planetary input gear 31a, a planetary carrier gear 31b, a planetary sun gear 31c, and a planetary gear 31d. The planetary input gear 31a and the planetary sun gear 31c are rotatably supported by the shaft 31e. Planetary input gear 31a, planetary carrier gear 31b, and planetary sun gear 31c are rotatable about axis 31e and rotational axis RA.

A planetary input gear (input member) 31a meshes with the refeed input gear 32, and is a gear to which the driving force from the motor M is transmitted. The planetary input gear 31a includes an input gear portion 31a1 that meshes with the paper refeed input gear 32, and an internal gear portion 31a2. The input gear portion 31a1 and the internal gear portion 31a2 are arranged coaxially. The internal gear portion 31a2 of the planetary input gear 31a meshes with the planetary gear 31d, and transmits driving force to the planetary gear 31d.

The planetary sun gear (sun member, sun gear) 31c has a sun gear portion 31c1 and a regulated portion 31c2. The sun gear portion 31c1 is located inside the internal gear portion 31a2 in the direction orthogonal to the rotation axis RA. In other words, the internal gear portion 31a2 is arranged to surround the sun gear portion 31c1.

The planetary carrier gear (carrier member) 31b has an output gear portion (output portion) 31b1 that meshes with the refeeding idler gear 33, and a support shaft 31b2 that supports the planetary gear 31d. Since the output gear portion 31b1 is engaged with the refeeding idler gear 33, the refeeding roller 8a is driven (rotated) by the output gear portion 31b1 of the planetary carrier gear 31b when the planetary carrier gear 31b rotates.

The planetary gear 31d is rotatably supported by the support shaft 31b2 of the planetary carrier gear 31b, and meshes with the sun gear portion 31c1 of the planetary sun gear 31c and the internal gear portion 31a2 of the planetary input gear 31a. The driving force of the motor M is transmitted from the internal gear portion 31a2 to the planetary gear 31d, and the driving force transmitted to the planetary gear 31d is transmitted to the planetary sun gear 31c and the planetary carrier gear 31b.

The planetary gear 31d is supported by a support shaft 31b2 and is rotatable around the rotation axis RB. The rotation of the planetary gear 31d around the rotation axis RB is called the rotation of the planetary gear 31d. The planetary gear 31d can revolve around the sun gear portion 31c1. At this time, the planetary gear 31d revolves around the rotation axis RA.

The planetary gear 31d is arranged between the sun gear portion 31c1 and the internal gear portion 31a2 in the direction orthogonal to the rotation axis RA.

A flapper 35a of the solenoid 35 is movable between a regulated position for regulating the rotation of the planetary sun gear 31c and a retracted position retracted from the regulated position. When the flapper 35a is at the regulated position, the regulated portion 31c2 of the planetary sun gear 31c contacts the flapper 35a, and the rotation of the planetary sun gear 31c is regulated. When the flapper 35a is at the retracted position, the flapper 35a is separated from the regulated portion 31c2 of the planetary sun gear 31c, allowing the planetary sun gear 31c to rotate.

In this embodiment, the flapper 35a is biased from the retracted position toward the restricted position by the spring 35c. Further, when a current flows through the coil 35b and a magnetic field is generated, the flapper 35a is moved from the restricted position to the retracted position against the biasing force of the spring 35c. That is, the coil 35b is a member that moves the flapper 35a from the restricted position to the retracted position, and the spring 35c is a member that moves the flapper 35a from the retracted position to the restricted position. The flapper 35a may be moved from the restricted position to the retracted position by the spring 35c, and the flapper 35a may be moved from the retracted position to the restricted position by the coil 35b.

<Switching between rotating and stopping the refeed roller>
Switching between rotation and stoppage of the paper re-feeding roller 8a will be described with reference to FIG. 6 (FIGS. 6A and 6B) are perspective views of the planetary gear unit 31 and the solenoid 35. FIG. FIG. 6(a) is a perspective view of the planetary gear unit 31 and the solenoid 35 with the flapper 35a at the restricting position. FIG. 6B is a perspective view of the planetary gear unit 31 and the solenoid 35 with the flapper 35a at the retracted position.

Rotation/stop of the planetary carrier gear 31b of the planetary gear unit 31 is switched by turning on/off the solenoid 35, thereby switching rotation/stop of the paper refeed roller 8a.

As shown in FIG. 6(a), when the flapper 35a is in the restricting position, the flapper 35a of the solenoid 35 is engaged with the engaged portion 31c2 of the planetary sun gear 31c, thereby restricting the rotation of the planetary sun gear 31c. , the planetary sun gear 31c is stopped. On the other hand, as shown in FIG. 6B, when the flapper 35a is in the retracted position, the flapper 35a of the solenoid 35 is separated from the engaged portion 31c2 of the planetary sun gear 31c, allowing the planetary sun gear 31c to rotate. be done.

As described above, the solenoid 35 includes a flapper 35a, a coil 35b, and a spring 35c (see FIGS. 4(a) and 4(b)). When power is supplied to the solenoid 35, the coil 35b is magnetized to attract the flapper 35a, and the flapper 35a is positioned at the retracted position against the biasing force of the spring 35c. When power is not supplied to the sonoid 35, the coil 35b is not magnetized, and the flapper 35a is positioned at the restricted position by the biasing force of the spring 35c.

In this embodiment, when the flapper 35a and the locked portion 31c2 of the planetary sun gear 31c are locked, the flapper 35a receives force from the locked portion 31c2 when the planetary sun gear 31c is about to rotate. In this embodiment, the flapper 35a and the engaged portion 31c2 are configured so that the flapper 35a receives a force in the direction of approaching the planetary sun gear 31c. As a result, the planetary sun gear 31c can be more reliably locked by the flapper 35a.

With reference to FIG. 6(a), the operation when the solenoid 35 is not supplied with power and the flapper 35a is in the restricted position (restricted state, locked state) will be described.

Since the input gear portion 31a1 (see FIG. 5) of the planetary input gear 31a is meshed with the refeeding input gear 32, the driving force of the motor M always rotates the internal gear portion 31a2 of the planetary input gear 31a counterclockwise ( Da1 direction).

A driving force is transmitted from the internal gear portion 31a2 to the planetary gear 31d that meshes with the internal gear portion 31a2 of the planetary input gear 31a. On the other hand, the latched portion 31c2 of the planetary sun gear 31c is engaged with the flapper 35a of the solenoid 35 to restrict the rotation of the sun gear portion 31c1 of the planetary sun gear 31c. Therefore, the planetary gear 31d cannot drive the sun gear portion 31c1. On the other hand, the planetary gear 31d receives a large reaction force from the sun gear portion 31c1. The driving force from the internal gear portion 31a2 and the large reaction force from the sun gear portion 31c1 act on the planetary gear 31d, so that the planetary gear 31d rotates counterclockwise around the support shaft 31b2. It revolves counterclockwise (Dd1 direction) around the sun gear portion 31c1.

As the planetary gear 31d revolves, force acts on the support shaft 31b2 from the planetary gear 31d, and the planetary carrier gear 31b having the support shaft 31b2 also rotates counterclockwise (Db1 direction). As the planetary carrier gear 31b rotates, a driving force is transmitted to the refeeding roller gear 34 via the refeeding idler gear 33 meshing with the output gear portion 31b1, and the refeeding roller 8a rotates. The sheet S is conveyed by rotating the re-feeding roller 8a.

That is, when the planetary input gear 31a is rotated by the driving force of the motor M while the flapper 35a is in the regulated position, the planetary gear 31d revolves around the sun gear portion 31c1 to rotate the planetary gear having the support shaft 31b2. The carrier gear 31b and the refeeding roller 8a rotate.

Next, with reference to FIG. 6(b), the operation when power is supplied to the solenoid 35 and the flapper 35a is in the retracted position (retracted state, released state, unlocked state) will be described.

The driving force of the motor M causes the internal gear portion 31a2 of the planetary input gear 31a to rotate counterclockwise (Da1 direction), and the driving force is transmitted from the internal gear portion 31a2 to the planetary gear 31d.

When power is supplied to the solenoid 35, the flapper 35a is retracted from the regulated portion 31c2 of the planetary sun gear 31c, allowing the planetary sun gear 31c to rotate freely. Therefore, the planetary sun gear 31c rotates clockwise (Dc1 direction) by the driving force transmitted from the planetary gear 31d to the sun gear portion 31c1. When the planetary sun gear 31c is allowed to rotate, the reaction force that the planetary sun gear 31d receives from the planetary sun gear 31c is very small. Therefore, the planetary carrier gear 31b does not revolve around the sun gear portion 31c1, but rotates counterclockwise (Dd2 direction) about the support shaft 31b2. The force received by the support shaft 31b2 that supports the planetary gear 31d is also very small, and the planetary carrier gear 31b does not rotate. As a result, the planet carrier gear 31b cannot rotate the paper feed roller 8a, and the rotation of the paper re-feed roller 8a stops.

That is, when the planetary input gear 31a is rotated by the driving force of the motor M while the flapper 35a is in the retracted position, the planetary sun gear 31c rotates while the planetary carrier gear 31b having the support shaft 31b2 and the re-feeding gear 31b rotate. Rotation of the paper roller 8a is suppressed. As a result, the planetary carrier gear 31b and the refeeding roller 8a do not rotate.

In this manner, by switching between ON and OFF of the solenoid 35 (whether or not power is supplied to the coil 35b), rotation and stop of the paper re-feeding roller 8a can be switched.

Further, as described above, the motor M also transmits drive to the fixing device, the photosensitive drum 4, the paper feeding roller 2a, the intermediate conveying roller 9a, the conveying roller 3a, and the paper discharge roller 7a. Therefore, even when the flapper 35a is at the retracted position and the paper refeeding roller 8a is stopped, the fixing device, the photosensitive drum 4, the paper feeding roller 2a, the intermediate conveying roller 9a, the conveying roller 3a, and the paper discharge roller 7a can be driven by a motor M;

The control unit 150 controls power supply to the coil 35b of the solenoid 35 based on signals from sensors that detect the sheet S (for example, the transport sensor 21, the paper discharge sensor 22, and the paper re-feed sensor 23). In other words, the controller 150 controls the operation of the coil 35b.

<Resolving sheet jams>
A jam of the sheet S inside the image forming apparatus 100 is called a sheet jam (paper jam, jam). When a sheet jam occurs, the sheet S does not pass a sensor that detects the passage of the sheet S (for example, the transport sensor 21, the paper discharge sensor 22, and the re-feed sensor 23) within a predetermined time. In this case, the control unit 150 determines that a sheet jam has occurred, and stops the operation of the image forming apparatus 100 so that the operation of conveying the sheet S is stopped.

Sheet jams are caused by various causes such as skewing of the sheet S and bending of the sheet S. FIG. When a sheet jam occurs, the user needs to remove the sheet S from inside the image forming apparatus 100 to clear the sheet jam. It is preferable that the force for removing the sheet S is small.

A sheet jam may occur while the sheet S is in contact with the re-feeding roller 8a. 7 and 8, in a state in which the sheet S is in contact with the re-feeding roller 8a (a state in which the sheet S is sandwiched between the re-feeding roller 8a and the driven re-feeding roller 8b), A description will be given of how to clear a sheet jam.

In the image forming apparatus 100 of the present embodiment, the positions of the re-feeding roller 8a and the driven re-feeding roller 8b when handling a sheet jam are the positions where image formation is performed on the sheet S (the position where the sheet S is conveyed). position). That is, when the sheet jam of the sheet S is handled, a mechanism for separating the re-feeding roller 8a and the driven re-feeding roller 8b or changing the pressure between the re-feeding roller 8a and the driven re-feeding roller 8b is used. No mechanism is required.

FIG. 7 is a diagram for explaining the operation of the planetary gear unit 31 when the sheet jam is cleared. FIG. 7A is a diagram for explaining the operation of the planetary gear unit 31 when the sheet jam is cleared according to the comparative example. FIG. 7B is a diagram for explaining the operation of the planetary gear unit 31 when the sheet jam is cleared according to this embodiment.

8 (FIGS. 8A, 8B, and 8C) are sectional views of the image forming apparatus 100 when the sheet jam is cleared.

As shown in FIGS. 8A to 8C, the image forming apparatus 100 has a door 41. FIG. The door 41 is an openable/closable member that covers the transport path along which the sheet S is transported. By opening the door 41, the re-conveyance path 140 is exposed, and the sheet S remaining in the re-conveyance path 140 can be removed. The image forming apparatus 100 also has a door sensor (open/close detection unit) 42 that detects opening/closing of the door 41 .

When clearing a sheet jam while the sheet S is in contact with the re-feeding roller 8a, the user pulls the sheet S in a direction opposite to the conveying direction of the sheet S by the re-feeding roller 8a, thereby removing the sheet S from the apparatus main body 100A. Sheet S can be removed from the interior. At this time, an external force is applied from the sheet S to the re-feeding roller 8a, and the re-feeding roller 8a is rotated. At this time, the direction of rotation of the re-feeding roller 8a is opposite to the direction of rotation (clockwise in FIGS. 8A to 8C) when conveying the sheet S (see FIGS. 8A to 8C). counterclockwise).

As the refeeding roller 8a rotates, the planetary carrier gear 31b receives force via the refeeding roller gear 34 and the refeeding idler gear 33, and rotates about the shaft 31e and the rotation axis RA as shown in FIG. , (b) in the clockwise direction (Db2 direction). As the planetary carrier gear 31b rotates clockwise (Db2 direction), the support shaft 31b2 supporting the planetary gear 31d also rotates clockwise (Db2 direction).

In the comparative example, as shown in FIG. 7A, power is not supplied to the solenoid 35, and the flapper 35a is positioned at the restricted position. In this state, the planetary sun gear 31c cannot rotate, and when the support shaft 31b2 rotates clockwise (Db2 direction), the planetary sun gear 31d receives a very large reaction force from the planetary sun gear 31c. As a result, the planetary gear 31d revolves clockwise (Db3 direction) around the sun gear portion 31c1 while rotating clockwise in FIG. 7A about the support shaft 31b2.

As the planetary gear 31d rotates and revolves around the sun gear portion 31c1, a force that rotates the planetary input gear 31a clockwise (in the direction of Da2) is applied to the internal gear portion 31a2 of the planetary input gear 31a from the planetary gear 31d. is transmitted. The force transmitted to the planetary input gear 31a is transmitted to the motor M, which is the drive source, via the paper refeed input gear 32. As shown in FIG.

That is, in the comparative example shown in FIG. 7A, it is necessary to rotate the refeeding roller 8a and the motor M by pulling the sheet S. As shown in FIG. Therefore, the user needs to pull the sheet S with a large force. In addition, the force applied to the sheet S also increases.

On the other hand, as shown in FIG. 7B, in the configuration according to the present embodiment, power is supplied to the solenoid 35 during sheet jam processing, so that the flapper 35a is positioned at the retracted position.

Specifically, when the sheet detection unit (conveyance sensor 21, paper discharge sensor 22, re-feed sensor 23) for detecting the sheet S detects an abnormality in the conveyance of the sheet S (sheet jam), the solenoid 35 is supplied with electric power, and the coil 35b moves the flapper 35a to the retracted position. That is, the control section 150 controls the operation of the coil 35b (the operation of the power supply section PS) so that the flapper 35a is positioned at the retracted position.

Since the flapper 35a positioned at the retracted position is separated from the planetary sun gear 31c, the planetary sun gear 31c is in a rotatable state. On the other hand, the planetary input gear 31 a is connected to the motor M via the paper refeed input gear 32 .

When the support shaft 31b2 rotates clockwise (Db2 direction) in this state, the planetary gear 31d also revolves clockwise around the rotation axis RA. At this time, since the rotation of the planetary sun gear 31c is not restricted, the planetary sun gear 31c can rotate with a small force, and the reaction force received by the planetary sun gear 31c from the planetary sun gear 31c is very small. On the other hand, since the planetary input gear 31a is connected to the motor M via the paper refeeding input gear 32, the planetary gear 31d receives a large reaction force from the internal gear portion 31a2 of the planetary input gear 31a. As a result, the planetary gear 31d does not drive the planetary input gear 31a, but rather the planetary sun gear 31c. At this time, the planetary gear 31d rotates counterclockwise around the support shaft 31b2 while revolving around the rotation axis RA.

That is, in the present embodiment shown in FIG. 7B, the motor M is not rotated when the sheet S is pulled and the refeeding roller 8a is rotated to clear the sheet jam. Therefore, the force required to clear the sheet jam should be sufficient to rotate the planetary sun gear 31c via the planetary gear 31d. Therefore, compared with the configuration shown in FIG. 7A, it is possible for the user to pull the sheet S with less force to clear the sheet jam.

The force for pulling the sheet S according to the present embodiment shown in FIG. 7B is 80% less than the force for pulling the sheet S in FIG. 7A.

<Power Supply to Solenoid>
Control when power is supplied to the solenoid 35 will be described with reference to FIGS. 9 and 10 are block diagrams showing sheet jam clearing according to the present embodiment.

As shown in FIG. 9, in the image forming apparatus 100 according to the present embodiment, when a sheet jam is detected by a sheet detection unit (recording material detection unit) that detects a sheet S, electric power is supplied to the solenoid 35, the motor M, and the like. supply is interrupted. Detection of a sheet jam by any of the sheet detection units (conveyance sensor 21, paper ejection sensor 22, re-feed sensor 23) for detecting the sheet S is called jam detection.

After that, power is immediately supplied to the solenoid 35 (the solenoid is turned on), and the flapper 35a is positioned at the retracted position. Only when the control unit 150 determines from the signal of the sheet detection unit that detects the sheet S that the sheet S is at a position where the refeeding roller 8a is rotated when the sheet S is pulled, the solenoid 35 may be turned on to move the flapper 35a to the retracted position.

After that, when the sheet jam is cleared, the jam detection is cleared. When the jam detection is resolved, power supply to the solenoid 35 is stopped (solenoid is turned off), and the image forming apparatus 100 becomes ready for image forming operation (print ready).

Here, the temperature of the solenoid 35 rises due to the power being supplied to the solenoid 35 . In order to suppress the temperature rise of the solenoid 35, for example, when the sheet detection unit detects a sheet jam, the voltage and the duty ratio for supplying power to the solenoid 35 can be lowered compared to when the sheet S is being conveyed. It is valid.

When clearing the sheet jam, the motor M is stopped and the driving force is not transmitted to the planetary gear unit 31 . Since the planetary sun gear 31c does not receive the driving force from the motor M, the force applied from the planetary sun gear 31c to the flapper 35a of the solenoid 35 is very small. Therefore, it is possible to attract the flapper 35a of the solenoid 35 with less electric power than when the sheet S is being conveyed.

In order to suppress the temperature rise of the solenoid 35, for example, it is effective to shorten the time during which power is supplied to the solenoid 35 as much as possible. Therefore, in addition to the sheet jam detection by the sheet detection unit that detects the sheet S, the door sensor 42 that detects opening/closing of the door 41 may be used to control the ON/OFF of the solenoid 35 . The ON/OFF control of the solenoid 35 will be described below with reference to FIGS. 8(a) to (c) and FIG.

When a sheet jam occurs with the sheet S between the re-feeding roller 8a and the driven re-feeding roller 8b, three patterns shown in FIGS. 8A to 8C are assumed. In order to clear the sheet jam under these conditions, the user needs to pull the sheet S in the direction opposite to the conveying direction of the re-feeding roller 8a.

In FIG. 8A, the sheet S is sandwiched between the discharge roller 7a and the second opposing roller 7c, and sandwiched between the re-feeding roller 8a and the driven re-feeding roller 8b. In FIG. 8A, the sheet discharge sensor 22 detects the sheet S, and the re-feed sensor 23 does not detect the sheet S. In FIG. In this state, the user can remove the sheet jam by pulling the sheet S from the sheet stacking tray 1 without opening the door 41 .

In FIG. 8B, the sheet S is sandwiched between the discharge roller 7a and the second opposing roller 7c, and sandwiched between the re-feeding roller 8a and the driven re-feeding roller 8b. In FIG. 8B, the sheet S is detected by the sheet discharge sensor 22 and the sheet re-feed sensor 23 . In this state, the user can remove the sheet jam by pulling the sheet S from the sheet stacking tray 1 side or the door 41 side.

In the states shown in FIGS. 8A and 8B, the user does not need to open the door 41 to clear the sheet jam, so power is supplied to the solenoid 35 even when the door 41 is not opened. There is a need. Therefore, the controller 150 supplies power to the solenoid 35 without using the detection result of the door sensor 42 to move the flapper 35a to the retracted position. When a sheet jam occurs, the controller 150 can determine that the sheet S is in the state shown in FIGS. 8A and 8B when the discharge sensor 22 detects the sheet S. can.

In FIG. 8C, the sheet S is sandwiched between the re-feeding roller 8a and the driven re-feeding roller 8b, and between the transport roller 3a and the driven transport roller 3b. In FIG. 8A, the sheet discharge sensor 22 does not detect the sheet S, and the sheet re-feed sensor 23 detects the sheet S. In FIG. In this state, the user needs to open the door 41 and pull the sheet S in order to clear the sheet jam. Therefore, when the door sensor 42 detects that the door 41 is opened, the controller 150 supplies power to the solenoid 35 to move the flapper 35a to the retracted position. When a sheet jam occurs, the control unit 150 detects the sheet S as shown in FIG. It can be determined that the

FIG. 10 shows the order of control of power supply to the solenoid 35 in the states shown in FIGS. 8(a) to (c). In FIG. 10, control for supplying power to the solenoid 35 is divided into two patterns.

In one pattern, when a jam is detected, the sheet re-feed sensor 23 detects the presence of the sheet S, the sheet discharge sensor 22 does not detect the sheet S, and the door sensor 42 detects that the door 41 is open. , the solenoid 35 is energized. This corresponds to the state of FIG. 8(c). In this pattern, the power supply to the solenoid 35 is stopped when the jam detection is cleared or when the door sensor 42 detects the closed state of the door 41 .

In another pattern, power is supplied to the solenoid 35 when a jam is detected and the sheet discharge sensor 22 detects the sheet S. This corresponds to the states of FIGS. 8(a) and 8(b). In this pattern, power supply to the solenoid 35 is stopped when the jam detection is resolved.

The time during which power is supplied to the solenoid 35 can be shortened by the control method described above.

As described above, according to the image forming apparatus 100 of the present embodiment, the flapper 35a is moved to the retracted position so that the user's pulling force on the sheet S is not transmitted to the motor M when handling the sheet jam. As a result, the force with which the user pulls the sheet S can be reduced. In addition, since the flapper 35a moves to the retracted position without any special operation by the user, it is possible to prevent an increase in work performed by the user.

(Example 2)
Example 2 will be described with reference to FIG. In the present embodiment, portions different from the first embodiment will be mainly described, and descriptions of the same portions as the first embodiment will be omitted.

In the second embodiment, when the door 41 is opened to expose the re-conveyance path 140, the flapper 35a moves to the retracted position in conjunction with the movement of the door 41. FIG.

FIG. 11 is a diagram showing operations of the door 41 and the solenoid 35 according to the second embodiment. FIG. 11(a) shows the operation of the door 41 and the solenoid 35 when the door 41 is closed. FIG. 11B shows the operation of the door 41 and the solenoid 35 when the door 41 is opened.

As shown in FIGS. 11A and 11B, the door 41 has a door rotation center 45, a door portion 46, and an arm 47. As shown in FIGS. Further, the image forming apparatus 100 has an intermediate lever (interlocking lever, interlocking member, intermediate member) 51 for interlocking movement of the door 41 and movement of the flapper 35a. The intermediate lever 51 has a lever rotation center 52 , a pressed portion 53 and a pressing portion 54 . The image forming apparatus 100 has a lever abutment portion 55 as an abutment portion of the intermediate lever 51 .

The conveying of the sheet S and the image forming operation on the sheet S are performed while the door 41 is closed. As shown in FIG. 11A, when the door 41 is closed (the door is in the closed position), the arm 47 of the door 41 and the pressed portion 53 of the intermediate lever 51 are separated. The intermediate lever 51 is in a state of abutting against the lever abutting portion 55 by an urging means such as a spring (not shown), and the pressing portion 54 is separated from the flapper 35a. The position of the intermediate lever 51 at this time can be called a separated position (non-pressing position). When the intermediate lever 51 is at the separated position, the intermediate lever 51 is separated from the flapper 35a at the restricted position and the flapper 35a at the retracted position. Therefore, during the transportation of the sheet S and the image forming operation on the sheet S, the intermediate lever 51 is in a state away from the flapper 35a.

Operations of the door 41, the intermediate lever 51, and the flapper 35a when the sheet detection unit of the image forming apparatus 100 detects a sheet jam and the user opens the door 41 will be described with reference to FIG. 11B.

When the door 41 is opened, the door 41 rotates around the door rotation center 45 . As a result, the arm 47 of the door 41 comes into contact with the pressed portion 53 of the intermediate lever 51 and rotates the intermediate lever 51 against the biasing force of the biasing means. As the intermediate lever 51 rotates, the pressing portion 54 presses the flapper 35a of the solenoid 35, and the flapper 35a rotates. When the door 41 is completely opened, the flapper 35a of the solenoid 35 moves to the retracted position and is separated from the regulated portion 31c2 of the planetary sun gear 31c. In other words, the flapper 35a can move to the retracted position in the same manner as when the solenoid 35 is energized.

According to the configuration of this embodiment, the user can move the flapper 35a to the retracted position by opening the door 41 . Further, even if power is not supplied to the solenoid 35, the flapper 35a is moved to the retracted position in conjunction with the operation of opening the door 41. Therefore, when the door 41 is open, the control unit 150 does not supply power to the solenoid 35 and can suppress the temperature rise of the solenoid 35 .

Note that the control unit 150 may stop supplying power to the solenoid 35 when the door sensor 42 detects that the door 41 is opened. Further, when it is determined that the door 41 needs to be opened in order to clear the sheet jam (for example, when the sheet S is in the state shown in FIG. 8C), the controller 150 The power supply to the solenoid 35 may be stopped.

As described above, according to the image forming apparatus 100 of the present embodiment, the flapper 35a is moved to the retracted position so that the user's pulling force on the sheet S is not transmitted to the motor M when handling the sheet jam. As a result, the force with which the user pulls the sheet S can be reduced. Further, since the flapper 35a is moved to the retracted position by the user's operation for accessing the sheet S, an increase in the work performed by the user is suppressed.

(Example 3)
A third embodiment will be described with reference to FIGS. 12 and 13. FIG. In the present embodiment, portions different from the first embodiment will be mainly described, and descriptions of the same portions as the first embodiment will be omitted.

12(a), (b), and FIG. 13 are diagrams showing the relationship between the planetary sun gear 31c and the solenoid 35 according to this embodiment.

In the first embodiment, when the planetary sun gear 31c tries to rotate with the flapper 35a at the restricted position restricting the restricted portion 31c2, the flapper 35a receives a force in the direction of approaching the planetary sun gear 31c. As a result, when the sheet S is conveyed, the planetary sun gear 31c can be reliably stopped by the flapper 35a. On the other hand, however, when the flapper 35a is not retracted, a large force is required to pull the sheet S when clearing the sheet jam.

Therefore, in this embodiment, when the flapper 35a at the regulated position receives a force of a predetermined magnitude or more from the planetary sun gear 31c, the flapper 35a is retracted from the regulated position.

In this embodiment, as shown in FIG. 12, the force that the flapper 35a of the solenoid 35 receives from the regulated portion 31c2 of the planetary sun gear 31c acts in the direction of separating the flapper 35a from the planetary sun gear 31c. Specifically, assuming that the straight line connecting the portion where the flapper 35a and the regulated portion 31c2 abut and the center of rotation of the flapper 35a is Lf, the direction of the force that the flapper 35a receives from the planetary sun gear 31c is relative to Lf. This is the direction inclined by θ ₁ in the direction away from the planetary sun gear 31c.

On the other hand, even if the force that the flapper 35a receives from the regulated portion 31c2 of the planetary sun gear 31c acts in the direction of separating the flapper 35a from the planetary sun gear 31c, it is necessary to drive the refeeding roller 8a.

In order for the drive to be transmitted from the motor M to the re-feeding roller 8a, the planetary gear 31d must revolve around the sun gear 31c and the planetary carrier gear 31b must rotate. Therefore, when the motor M drives the paper re-feeding roller 8a, the flapper 35a must be kept engaged with the regulated portion 31c2.

The length from the center of rotation of the planetary carrier gear 31b to the support shaft 31b2 that supports the planetary gear 31d is R ₁ ; Let T be the torque of At this time, the force _F2 received by the support shaft 31b2 of the planetary carrier gear 31b and the planetary gear 31d can be expressed as follows.
(Formula 1) F ₂ =α×T×(1/R ₁ )
This F2 is the resultant force of the reaction force F3 received by the planetary gear 31d from the planetary sun gear 31c and the force _F3 ' received from the _planetary input gear 31a. Assuming that the pressure angle of the planetary gear 31d, the sun gear portion 31c1, and the internal gear portion 31a2 is _θ2 , _F3 can be expressed as follows.
(Formula 2) F ₃ =(1/2)×F ₂ ×(1/cos θ ₂ )
The force _F4 applied to the flapper 35a by the regulated portion 31c2 of the planetary sun gear 31c is determined by the pitch circle radius _R3 of the sun gear portion 31c1 of the planetary sun gear 31c and the radius R of the regulated portion 31c2 from the rotation center of the planetary sun gear 31c. ₄ can be expressed as below.
(Formula 3) F ₄ =F ₃ ×cos θ ₂ ×(R ₃ /R ₄ )
In this embodiment, this force _F4 acts in a direction inclined by _θ1 with respect to Lf. Therefore, when the holding force of the flapper 35a of the solenoid 35 held by the spring 35c is _F5 , the condition for the flapper 35a to keep engaging with the regulated portion 31c2 can be expressed by the following equation.
(Formula 4) F ₅ >F ₄ ×sin θ ₁
Note that F4 can be expressed by the following equation using torque T.
(Formula 5) F ₅ >(1/2)×α×T×(1/R ₁ )×(R ₃ /R ₄ )
In the image forming apparatus 100 of this embodiment, _F4 is 20 gf. The force of the spring 35c of the solenoid 35 is set so that the force _F5 is 15 gf. In this case, even if _θ1 is set to 15°, the flapper 35a can continue to engage with the regulated portion 31c2.

Next, let _F6 be the force required to pull the sheet S to rotate the refeed roller 8a in order to clear the sheet jam, and _R5 be the radius of the refeed roller 8a. At this time, assuming that the torque generated in the re-feeding roller 8a is _Td , the following equation is satisfied.
(Formula 6) T _d =F ₆ ×R ₅
Therefore, the force _F7 applied to the flapper 35a by the regulated portion 31c2 of the planetary sun gear 31c by pulling the sheet S can be expressed by the following equation.
(Formula 7) _F7 >(1/2)*α* _F6 * _R5 *(1/ _R1 )*( _R3 / _R4 )
Therefore, the conditions under which the flapper 35a of the solenoid 35 is retracted from the regulated position by receiving force from the regulated portion 31c2 of the planetary sun gear 31c by pulling the sheet S can be expressed as follows.
(Equation 8) F ₅ <F ₇ ×sin θ ₁
By satisfying both Equation 4 and Equation 8, it is possible to rotate the refeeding roller 8a by the driving force of the motor M and to pull the sheet S to retract the flapper 35a of the solenoid 35 from the regulating position. becomes. Incidentally, in this embodiment, the force _F6 required for handling the sheet jam is 500 gf or less.

As described above, according to the image forming apparatus 100 of the present embodiment, the flapper 35a is moved to the retracted position so that the user's pulling force on the sheet S is not transmitted to the motor M when handling the sheet jam. As a result, the force with which the user pulls the sheet S can be reduced. In addition, since the flapper 35a moves to the retracted position without any special operation by the user, it is possible to prevent an increase in work performed by the user.

(Other examples)
In Embodiments 1 to 3, the so-called monochrome image forming apparatus 100 having a single photosensitive drum 4 has been described. However, the present invention is not limited to this, and can be applied to a color image forming apparatus or a rotary type color image forming apparatus having one photosensitive drum 4 . Further, it can also be applied to an image forming apparatus using a belt for conveying a transfer material.

In the first to third embodiments, the solenoid 35 is used to switch between a state in which the rotation of the planetary sun gear 31c is restricted and a state in which the rotation is permitted. However, the solenoid 35 is an example of a lock mechanism, and means for switching between a state in which rotation of the planetary sun gear 31c is restricted and a state in which rotation is permitted is not limited to the solenoid 35. For example, a clutch such as an electromagnetic clutch may be used. Moreover, the structure which moves the member corresponded to the flapper 35a by moving members, such as a cam, may be sufficient.

Although the number of planetary gears 31d is one in Examples 1 to 3, the planetary gear unit 31 may have a plurality of planetary gears 31d. The number of planetary gears 31d may be two, or three or more.

In Examples 1 to 3, the flapper 35a of the solenoid 35 is directly engaged with the regulated portion 31c2 of the planetary sun gear 31c. good. By using the intermediate member, it is possible to reduce the collision noise of the flapper 35a.

In Examples 1 to 3, power is supplied to the solenoid 35 in order to temporarily stop the paper refeed roller 8a when double-sided printing is performed. However, power may be supplied to the solenoid 35 when single-sided printing is performed. By supplying power to the solenoid 35 when single-sided printing is executed, it is possible to cut off the transmission of the driving force to the paper re-feeding roller 8a. As a result, the load on the motor M can be reduced.

Each of the embodiments described above can be appropriately combined as necessary.

8a Refeed roller 31 Planetary gear unit 31a Planetary input gear 31b Planetary carrier gear 31c Planetary sun gear 31d Planetary gear 35 Solenoid 35a Flapper 35b Coil 41 Door

Claims (14)

A conveying device for conveying a recording material,
an input member having an internal gear portion;
a sun member having a sun gear portion;
a carrier member having a support shaft;
a planetary gear meshing with the sun gear portion and the internal gear portion and rotatably supported by the support shaft;
a roller driven by the carrier member for conveying the recording material;
a regulating position for regulating rotation of the sun member; a regulating member movable to a retracted position retracted from the regulating position;
a moving member that moves the regulating member between the regulating position and the retracted position;
a recording material detection unit that detects the recording material;
has
When the input member rotates while the regulating member is in the regulating position, the planetary gear revolves around the sun gear portion, thereby rotating the carrier member having the support shaft and the roller. ,
The conveying device, wherein the moving member moves the regulating member to the retracted position when the recording material detecting unit detects an abnormality in conveying the recording material. an openable/closable opening/closing member that covers a conveying path along which the recording material is conveyed;
an opening/closing detection unit that detects opening/closing of the opening/closing member;
When the recording material detection unit detects an abnormality in the conveyance of the recording material and the opening/closing detection unit detects that the opening/closing member is opened, the moving member moves the regulating member to the retracted position. Moving,
2. The conveying apparatus according to claim 1, characterized in that: The moving member includes a magnetic field generating member that generates a magnetic field by being supplied with power,
3. The conveying device according to claim 1 or 2, characterized in that: a power supply unit that supplies power to the moving member;
a control unit that controls the power supply unit so that power is supplied to the magnetic field generating member when the recording material detection unit detects an abnormality in conveying the recording material;
4. The conveying apparatus according to claim 3, comprising: 5. The conveying apparatus according to claim 3, wherein the restricting member is positioned at the retracted position when power is supplied to the magnetic field generating member. 6. The conveying apparatus according to claim 5, wherein the regulating member is positioned at the regulating position when power is not supplied to the magnetic field generating member. A conveying device for conveying a recording material,
an input member having an internal gear portion;
a sun member having a sun gear portion;
a carrier member having a support shaft;
a planetary gear meshing with the sun gear portion and the internal gear portion and rotatably supported by the support shaft;
a roller driven by the carrier member for conveying the recording material;
a regulating position for regulating rotation of the sun member; a regulating member movable to a retracted position retracted from the regulating position;
a moving member that moves the regulating member between the regulating position and the retracted position;
an openable/closable opening/closing member that covers a conveying path along which the recording material is conveyed;
has
When the input member rotates while the regulating member is in the regulating position, the planetary gear revolves around the sun gear portion, thereby rotating the carrier member having the support shaft and the roller. ,
A conveying apparatus, wherein when the opening/closing member is opened so as to expose the conveying path, the regulating member moves to the retracted position in conjunction with movement of the opening/closing member. A conveying device for conveying a recording material,
an input member having an internal gear portion;
a sun member having a sun gear portion;
a carrier member having a support shaft;
a planetary gear meshing with the sun gear portion and the internal gear portion and rotatably supported by the support shaft;
a roller driven by the carrier member for conveying the recording material;
a regulating position for regulating rotation of the sun member; a regulating member movable to a retracted position retracted from the regulating position;
a moving member that moves the regulating member between the regulating position and the retracted position;
has
When the input member rotates while the regulating member is in the regulating position, the planetary gear revolves around the sun gear portion, thereby rotating the carrier member having the support shaft and the roller. ,
When the regulating member at the regulating position receives a force of a predetermined magnitude or more from the sun member, the regulating member retreats from the regulating position.
A conveying device characterized by: The moving member includes a magnetic field generating member that generates a magnetic field by being supplied with power,
9. The conveying device according to claim 7 or 8, characterized in that: 10. The conveying apparatus according to claim 9, wherein the restricting member is positioned at the retracted position when power is supplied to the magnetic field generating member. 11. The conveying apparatus according to claim 10, wherein the regulating member is positioned at the regulating position when power is not supplied to the magnetic field generating member. 12. The regulating member according to any one of claims 1 to 11, wherein the regulating member abuts against the sun member when in the regulating position, and separates from the sun member when in the retracted position. The transport device according to . 13. The carrier member having the support shaft and the roller are restrained from rotating when the input member rotates while the regulating member is at the retracted position. 1. The conveying device according to item 1. A conveying device according to any one of claims 1 to 13;
an image forming unit that forms an image on the recording material;
An image forming apparatus comprising:

Images