JP2001142271A - Image forming device - Google Patents

Abstract

(57) [Problem] To provide an image forming apparatus capable of reducing an operation force when closing a door and preventing an excessive force from being applied to a fixing pin. SOLUTION: When opening and closing a door 40 attached to a side portion of a device main body 51, a door 40 is opened by a damper means 41.
And the lifting means 42 pushes the door 40 upward through the damper means 41 when the door 40 is closed. Also, the door 40
Is closed, and when the door 40 is pushed upward by the lift means 42, the release means 32 and 35 prevent the urging force of the damper means 41 from acting on the door 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus, and more particularly to a door structure which is opened at the time of jam clearance or the like.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a laser beam printer, a copying machine, and a facsimile, a door is attached to an apparatus main body, for example, a side portion of the apparatus main body in order to perform a jam processing or the like. FIG. 11 is a diagram showing a schematic configuration of a laser beam printer (LBP) which is an example of such a conventional image forming apparatus. In FIG. 11, reference numeral 50 denotes a laser beam printer, and 51 denotes a laser beam printer main body.

The laser beam printer 50
Has an optical unit 1 that emits light in accordance with image information, as shown in FIG. 1; when an image is formed, first, light based on the image information is transmitted from the optical unit 1 to a photosensitive member as an electrophotographic photosensitive member. Irradiation is performed on the drum 2 to form a toner image.

Next, in synchronization with the formation of the toner image, a recording medium 3 which is a sheet such as transfer paper is picked up from a cassette 4 by a pickup roller 5, and then separated by a feed roller 6a and a retard roller 6b. The parts are separated into one sheet. Thereafter, the toner image formed on the photoreceptor drum 2 is transferred to the image forming section formed as a process cartridge A by reversing and conveying by a conveying means including a conveying roller pair 7 and a registration roller pair 8. Transfer roller 9 as
Is transferred to the recording medium 3 by applying a voltage to the recording medium 3.

Next, while the recording medium 3 after the transfer of the toner image is guided by a guide member 10, the recording medium 3 is conveyed to a fixing means 11 comprising a fixing roller 11a and a driving roller 11b for conveying the recording medium 3 by pressing the recording medium 3 against the roller 11a. Then, the transfer toner image is fixed on the recording medium 3. Thereafter, the recording medium 3 discharged from the fixing unit 11 by the fixing discharge roller pair 12 is conveyed by the discharge roller pairs 13 and 14, and is discharged to the discharge unit 16 through the reverse conveyance path 15 which is a conveyance path. are doing.

[0006] Regarding the discharge, the swingable flapper 17 which is a switching means for switching the transport path is operated.
It is also possible to discharge linearly by the discharge roller pair 18 without passing through the reverse conveyance path 15. When automatic double-sided printing is performed, the swingable flapper 21 is operated to guide the recording medium 3 into the double-sided unit 22, and then switched back by the reversing roller pair 23. The sheet is re-supplied toward the transport roller pair 7 by the sheet re-feed rollers 24 and 25 and the sheet re-feed roller pair 26.

In FIG. 1, reference numeral 27A denotes a cover which is a door which is openably and closably attached to the laser beam printer main body 51. The cover 27A is opened when a JAM occurs downstream of the fixing means 11 or the like. ,
JAM processing and the like are performed.

Here, the cover 27A is attached to a cover body 27 made of resin, a part of the reversal conveyance path 15,
7, 21 and a pair of discharge rollers 18 and the like.
Thus, it is attached to the laser beam printer main body 51 so as to be openable and closable with the lower end as a fulcrum. When the cover 27A is closed, a fixing pin 20 (see FIG. 11) provided on the laser beam printer main body side is engaged with a fixing hole 19 provided at the upper end of the inner wall surface of the cover 27A as shown in FIG. By doing so, it is fixed to the laser beam printer main body 51.

On the other hand, an opening / closing shaft 28 is inserted through the mounting end of the cover 27A as shown in FIG.
An elongated hole 27a extending in the height direction of the cover main body 27 is provided. When the cover 27A is closed by inserting the opening / closing shaft 28 into the elongated hole 27a, the cover 27 is closed.
A can move up and down.

When the cover 27A is closed, the cover 27A can be moved up and down.
By fixing the upper side of 7A, the cover 27 made of resin is exposed to the high temperature exposed in the container during transportation in summer.
Even if A greatly expands, the expansion is absorbed by the elongated hole 27a so that the cover 27A is not deformed.

By the way, the swing shaft 28 is located below the installation position of the double-sided unit 22 so that the cover 27A can be attached and detached by opening it in addition to the JAM processing (see FIG. 11). ). When the two-sided unit 22 is made detachable in this manner, the cover 27A becomes relatively large, and the cover 27A becomes heavy due to the provision of the flappers 17 and 21, the discharge roller pair 18, and the like. Need power.

Therefore, the conventional cover 27A is provided with a cover 27.
A damper means 53 as shown in FIG. Here, the damper means 53 includes a damper shaft 31 having one end rotatably supported by a shaft support portion 32 provided on the laser beam printer main body side, and a shaft support portion 27b on the inner wall surface of the cover main body 27. And a hollow damper cover 29 which is a main body into which a damper shaft 31 is inserted so as to be able to be pulled out from the moving end side.

In the figure, reference numeral 31c denotes a stopper member provided at the moving end of the damper shaft 31, 29d
Is provided at a predetermined position on the damper cover 29,
This is a locking portion for locking the stopper member 31c of the damper shaft 31. Here, the damper cover 29
By locking the stopper member 31c of the damper shaft 31 to the locking portion 29d, the damper means 53 can hold the cover 27A open at a predetermined angle.

In FIG. 1, a damper 30 is provided in the damper cover 29, and one end of the damper cover 29 is in contact with the inside of the rotating end of the damper cover 29, and the other end is in contact with the stopper member 31 c of the damper shaft 31. Spring 30
It is.

Then, the damper means 5 having such a configuration is provided.
In 3, when the cover 27 </ b> A is opened, the damper cover 29 first pivots downward together with the cover main body 27 while extracting the damper shaft 31 that has been mostly housed inside the damper cover. After this,
As the damper cover 29 moves, the damper spring 30
Stopper member 3 of damper shaft 31 while shrinking
1c is the locking portion 2 of the damper cover 29 as shown in FIG.
9d, thereby holding the cover 27A open at a predetermined angle.

Here, as the damper spring 30 is contracted in accordance with the increase in the opening angle of the cover 27A, a spring force F acts on the cover main body 27, and the component force f1 of the spring force F causes The opening and closing operation of the cover 27A is assisted.

[0017]

However, in such an image forming apparatus such as a conventional laser beam printer, when the cover 27A is opened and the double-sided unit 22 is attached and detached, the damper shaft 31 does not hinder attachment and detachment.
Must be lower than the position of the duplex unit 22.

When the position of the shaft support 32 is lowered as described above, as shown in FIG.
8, and the spring force F and the component force f1
Is larger. When the angle θ between the spring force F and the component force f1 increases, the component force f
1, the spring force F of the dambar spring 30 cannot be effectively applied to the cover 27A.

Here, in order to assist the opening and closing operation of the cover 27A, it is necessary to increase the spring force of the damper spring 30, but when the spring force is increased in this manner, the position where the cover 27A is closed and the vicinity thereof However, a large force is generated by the damper spring 30, and the cover 27A is pulled downward. Further, since the cover 27A is attached to the swing shaft 28 through the elongated hole 27a as described above, the cover 27A is larger than necessary.
It is lowered to the lower end of the elongated hole 27a by a force of zero and its own weight.

Therefore, in order to close the cover 27A, the cover 27A is closed against the force of the damper spring 30 and its own weight.
And the fixing pin 20 provided on the laser beam printer main body side must be engaged with the hole 19 provided on the upper portion of the cover 27A, so that not only a large operation force is required but also the operation feeling is poor. was there. Further, even after the cover 27A is closed, the force of the damper spring 30 is applied, so that an excessive force is applied to the fixing pin 20 and the fixing pin 20 is easily damaged.

Accordingly, the present invention has been made in view of such circumstances, and it is possible to reduce the operation force when closing a cover (door) and to prevent an unnecessary force from being applied to a fixing pin. It is an object of the present invention to provide an image forming apparatus capable of performing such operations.

[0022]

According to the present invention, a door is attached to a side portion of an apparatus main body, and the door is pivotally opened downward with a lower end as a fulcrum. In the image forming apparatus configured to be fixed to the apparatus main body, when opening and closing the door, damper means for urging the door in a direction to close the door, and when the door is closed, the door is moved upward through the damper means. Lift means for pushing up the door, and when the door is closed and the door is pushed upward by the lift means, the door is not pulled down by the urging force of the damper means. Is what you do.

According to the present invention, a door is attached to a side portion of the apparatus main body, and the door is pivoted downward by using a lower end as a fulcrum, and when the door is closed, the door is pivoted upward and the upper end is fixed to the apparatus main body. In the image forming apparatus, when the door is opened and closed, the door is urged in a direction to close the door, while one end is pivotally supported by the door, and the main body is moved from the moving end side of the main body. A damper means having a shaft inserted removably into the unit and one end of which is pivotally supported by the apparatus main body, and a biasing member for urging the shaft in a direction opposite to a direction in which the shaft is withdrawn; And a shaft support that engages with the shaft of the damper means and supports the shaft, and is provided between the main body of the damper means and the shaft support, and when the door is closed, Lift means provided with a pressing member for pressing the body part upward so as to push the door upward through the body part of the damper means; and the damper when the door is closed and the door is pushed upward by the lift means. Releasing means for releasing the engagement between the shaft and the shaft support so as not to apply the urging force of the urging member to the shaft of the means.

According to the present invention, the release means is formed on the shaft support, and engages with an engagement shaft provided at a lower end of a shaft of the damper means. An engagement groove having a non-acting portion that does not apply the urging force of the urging member to the shaft, and when the door is closed, the engaging shaft of the shaft is moved to the non-acting portion of the engagement groove. Characterized in that it is configured to be moved to

In the present invention, the release means is provided on the door, and when the door is closed, the releasing means is provided at an upper end of the shaft so as to move an engaging shaft of the shaft to a non-operating portion of the engaging groove. It is characterized in that it has a regulating member that moves the shaft downward by contact.

In the present invention, the release means is provided on the shaft, and when the door is closed, the engaging shaft of the shaft is moved to a non-operating portion of the engaging groove. A contact portion that contacts the portion and moves the shaft downward.

Further, in the invention, it is preferable that the door has a conveying path for conveying the sheet.

The present invention is characterized in that the door has a switching means for switching the transport path.

[0029]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a laser beam printer which is an example of an image forming apparatus according to a first embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 11 indicate the same or corresponding parts.

In FIG. 3, reference numeral 40 denotes a cover which is a door which is attached to the laser beam printer main body 51 so as to be openable and closable. The cover 40 is opened when a JAM occurs downstream of the fixing means 11 and the like. Processing and the like are performed.

Here, the cover 40 is attached to the cover body 27 made of resin, a part of the reversing conveyance path 15, the flapper 17,
21, a discharge roller pair 18 and the like are provided, and are attached to the laser beam printer main body 51 so as to be openable and closable with a lower end as a fulcrum by an opening / closing shaft 28 provided on the laser beam printer main body 51.

The cover 40 is provided with damper means 41 for assisting the opening and closing operation of the cover 40 as shown in FIG. And this damper means 41
A lift cover 33 is attached to a rotating end portion of a damper cover 29 which is a main body part of which is inserted into the damper shaft 31 so as to be movable within a predetermined range along the damper shaft 31.

When the cover 40 is closed, the lift cover 33, which is a pressing member, is provided so as to engage with the damper shaft 31 and abut on a shaft support 32 for supporting the damper shaft 31. The lift spring 34 is disposed between the lift spring 34 and the damper cover 29 as shown in FIG. The lift means 33 is constituted by the lift cover 33 and the lift spring 34.

When the cover 40 is closed, when the lift cover 33 comes into contact with the shaft support 32 as shown in FIG. 6, which will be described later, the moving end 29a of the damper cover 29 is thereafter moved.
The lift spring 34 is compressed as the slider approaches the shaft support portion 32, so that a force in the direction of lifting the damper cover 29 acts on the damper cover 29.

In this embodiment, the spring force of the lift spring 34 is set to a magnitude that can cancel the weight of the cover 40 in the closed state. By setting the spring force of the lift spring 34 in this manner, the fixing pin 20 (see FIG. 1) on the laser beam printer main body side is engaged with the upper fixing hole 19 shown in FIG. Even in this case, since the weight of the cover 40 is almost canceled, the cover 40 can be lifted smoothly.

In FIG. 3, reference numeral 29a1 denotes a locking claw formed on the moving end of the damper cover 29, and reference numeral 33a denotes a locking claw 29a1 formed on the side surface of the lift cover 33.
Is a slide groove for sliding.

When the cover 40 is closed by holding the locking claw 29a1 slidably in the slide groove 33a, the damper cover 29 is lifted by the lift spring 34.
Can be moved in the direction of the shaft support portion 32 while contracting. When the cover 40 is opened, the locking claw 2 is attached to the end of the slide groove 33a on the damper cover side.
9a1 is locked, whereby the lift cover 33 moves integrally with the damper cover 29.

In the same figure, reference numeral 29b denotes a locking hole formed in the side wall of the damper cover 29,
Is opened, a locking claw 31a1 provided on the moving end 31a of the damper shaft 31 is locked in the locking hole 29b. And the locking hole 2
9b, the damper means 41 can hold the damper shaft 31 in a state where the damper shaft 31 is pulled out by a predetermined amount.
It can be held in an open state at a predetermined angle where AM processing and the like can be performed.

In this embodiment, when the cover 40 is opened, the movable end 3 of the damper shaft 31 is moved.
1a is configured to protrude from the fixed side end portion 29c of the damper cover 29 as shown in FIG. Also,
The fixed end 31b of the damper shaft 31 projects slidably from the fixed end of the damper cover 29 and the lift cover 33.

On the other hand, a rib 35 is provided on the inner wall surface of the cover 40 as shown in FIG. 2, and when the cover 40 is closed, the moving end of the damper shaft 31
When a predetermined amount protrudes from the fixed-side end portion 29c, the rib 9 comes into contact with the rib 35.

Then, as described above, the damper shaft 31
After the moving end of the abutment contacts the rib 35 serving as the regulating member, if the cover 40 is further rotated in the closing direction, the moving end abuts on the rib 35, so that the damper shaft 31 cannot move any further. In the opposite direction, that is, the damper shaft 3
1 is moved in a direction in which the fixed end 31b is slid toward the shaft support.

Here, in the present embodiment, the shaft support 32 is provided with a shaft 31b provided on the fixed side end 31b of the damper shaft 31 as shown in FIGS. 4 (a) to 4 (c).
1 has a slide groove 32a for holding the slide 1 slidably in an oblique vertical direction. By holding the shaft 31b1 slidably in such a slide groove 32a, when the cover 40 is closed, the damper shaft 31 can be slid toward the shaft support.

The slide groove 32a is provided so that the spring force (biasing force) of the damper spring 30 is not applied in the direction of lowering the cover 40 after the damper shaft 31 slides toward the shaft support. It is configured so as not to come into contact with 31.

That is, the slide groove 32a is engaged with an engaging portion 32a1 which engages with the shaft 31b1 of the damper shaft 31 to support the damper shaft 31, as shown in FIGS. ) And (b), a non-acting portion 32a2 that does not apply the urging force of the damper spring 30 to the damper shaft 31. When the cover 40 is closed, the damper shaft 31 is moved toward the shaft support portion. And the shaft 31b1 is engaged with the engaging portion 32a shown in FIG.
1 to the non-acting portion 32a2 shown in FIG.

Thus, when the cover 40 is closed, the force of the damper spring 30 does not act in the direction of pushing down the cover 40, and its own weight is canceled by the lift spring 34. The force acting on the fixing pin 20 is almost eliminated.

Next, the operation of the thus constructed damper means 41 when the cover is closed will be described.

FIG. 5 is a view showing a state in which the cover 40 is opened. When the cover 40 in this state is rotated in the direction of the arrow with the opening / closing shaft 28 as a fulcrum and closed, the position shown in FIG. As a result, the lift cover 33 starts to abut on the shaft support 32. Further, the moving end 31a of the damper shaft 31 gradually starts to protrude from the fixed end 29c of the damper cover 29.

When the cover 40 is further closed,
Since the lift cover 33 is in contact with the shaft support 32, the lift spring 34 is compressed as the moving end of the damper cover 29 approaches the shaft support 32, and exerts a force in a direction to lift the damper cover 29.

When the cover 40 is further closed to the position shown in FIG. 7, the moving end of the damper shaft 31 comes into contact with the rib 35 of the cover body 27. When the moving end of the damper shaft 31 abuts in this manner, the damper shaft 31 cannot protrude any further, and when the cover 40 is further closed, the damper shaft 31 that has been supported by the shaft Fixed side end 31b (shaft 31b
1) starts to move diagonally downward along the slide groove 32a of the shaft support 32.

Here, the damper shaft 31
When the fixed-side end 31b starts moving obliquely downward, the force of the damper spring 30 is not applied in the direction of pulling the cover 40 downward. When the force of the damper spring 30 is not applied to the cover 40, the cover 40
Starts to be lifted by the spring force of the lift spring 34 acting to lift the damper cover 29.

Here, since this force is set to a force capable of canceling the own weight of the cover 40 in a state where the cover 40 is closed, after this, as shown in FIG. 8, after the cover 40 is closed, Even when the fixing pin 20 enters the fixing hole 19 on the upper part of the cover 40, the cover 40 is lifted smoothly because the weight of the cover 40 is almost canceled. Further, when the cover 40 is closed, the spring force of the damper spring 30 does not act in the direction of pushing down the cover 40, and its own weight is canceled by the lift spring 34. Is almost gone.

As described above, when the cover 40 is closed, the lift means 42 causes the cover 40 to be closed via the damper means 41.
And lift means 42
By preventing the spring force of the damper spring 30 from acting when the cover 40 is pushed upward, the operating force at the time of closing the cover 40 is reduced, the operational feeling is improved, and the fixing pin 20 is unnecessarily pressed. You can avoid applying force. Thereby, the operational feeling when closing the cover 40 can be improved, and damage to the fixing pin 20 can be prevented.

Next, a second embodiment of the present invention will be described.

FIG. 9 is a perspective view showing a state where a cover of a laser beam printer as an example of the image forming apparatus according to the present embodiment is opened. 2, the same reference numerals as those in FIG. 2 indicate the same or corresponding parts. FIG.
0 is a cross-sectional view showing the configuration of the damper means and the lift means. In this figure, the same reference numerals as those in FIG. 3 indicate the same or corresponding parts.

In FIGS. 9 and 10, reference numeral 37 denotes a damper shaft. In the present embodiment, the diameter of the fixed end 37b of the damper shaft 37 is increased. Further, in this embodiment, when the cover 40 is closed, the damper cover 29 is configured to move downward.

Here, with such a configuration,
When the cover 40 is closed and the damper cover 29 moves downward, the damper cover 29 comes into contact with the damper shaft 37, and the damper shaft 37 slides toward the shaft support. As a result, the first
As in the embodiment, the spring force of the damper spring 30 can be prevented from acting.

Further, with the configuration as in the present embodiment, the damper shaft 37 can be slid without providing the rib 35 (see FIG. 2). This eliminates the need for the cover main body 27 to receive the force of the damper spring 30, which is more advantageous against deformation of the cover main body 27 and the like.

In the above description, a laser beam printer has been exemplified as an image forming apparatus. However, the present invention is not limited to this. For example, other electrophotographic images such as an electrophotographic copying machine and a facsimile machine can be used. Naturally, it can also be used for forming equipment.

[0060]

As described above, according to the present invention, when the door is opened and closed, the door is urged in the closing direction by the damper means, and when the door is closed, the door is opened by the lift means via the damper means. When the door is pushed upward, the urging force of the damper means is not applied to the door when the door is pushed upward, so that the operating force for closing the door can be reduced.

Thus, the operational feeling when closing the cover can be improved. Further, since the force acting on the fixing pin of the cover can be greatly reduced, unnecessary force can be prevented from being applied to the fixing pin, and the fixing pin can be prevented from being damaged.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of a laser beam printer as an example of an image forming apparatus according to a first embodiment of the invention.

FIG. 2 is a perspective view showing a state where a cover of the laser beam printer is opened.

FIG. 3 is a sectional view showing a configuration of a damper unit and a lift unit that assist in opening and closing the cover.

FIG. 4 is a perspective view showing a relationship between the damper means and a shaft support.

FIG. 5 is a sectional view showing a state of a damper unit and a lift unit when the cover is opened.

FIG. 6 is a sectional view showing a state of the damper unit and the lift unit when the cover is started to be closed.

FIG. 7 is a sectional view showing a state of a damper unit and a lift unit immediately before closing the cover.

FIG. 8 is a sectional view showing a state of the damper unit and the lift unit when the cover is closed.

FIG. 9 is a perspective view showing a state in which a cover of a laser beam printer as an example of an image forming apparatus according to a second embodiment of the invention is opened.

FIG. 10 is a sectional view of a damper unit and a lift unit that assist in opening and closing the cover.

FIG. 11 is a cross-sectional view showing the overall configuration of a conventional laser beam printer.

FIG. 12 is a diagram showing a relationship between forces acting on the cover by a damper unit when the cover of the conventional laser beam printer is opened.

[Explanation of symbols]

 15 Reverse conveyance path 17, 21 Flapper 19 Fixing hole 20 Pin 28 Opening / closing shaft 29 Damper cover 30 Damper spring 31 Damper shaft 32 Shaft support 32a Sliding groove 32a1 Engaging part 32a2 Non-working part 33 Lift cover 34 Lift spring 35 Rib 40 Cover 41 Damper Means 42 Lifting means 50 Laser beam printer 51 Laser beam printer main body

Claims (7)

[Claims] 1. A door is attached to a side portion of an apparatus main body, and the door is opened by pivoting downward about a lower end as a fulcrum,
In an image forming apparatus in which an upper end portion is fixed to the apparatus main body after being rotated upward when closed, damper means for urging the door in a closing direction when the door is opened and closed, and the door is closed Lifting means for pushing the door upward through the damper means, when the door is closed and the door is pushed upward by the lifting means, the door is moved downward by the urging force of the damper means. An image forming apparatus which is configured not to be pulled down. 2. A door is attached to a side portion of the apparatus main body, and the door is opened by pivoting downward about a lower end as a fulcrum,
In an image forming apparatus in which the upper end is fixed to the apparatus main body after being turned upward when the door is closed, when the door is opened and closed, the door is urged in a closing direction while one end is pivotally supported by the door. A main body portion, and a shaft that is removably inserted into the main body portion from the moving end side of the main body portion and one end of which is pivotally supported by the device main body,
A biasing member having a biasing member for biasing the shaft in a direction opposite to a direction in which the shaft is pulled out; and a shaft supporting portion provided on the apparatus main body and engaging with a shaft of the damper unit to support the shaft, A pressing member provided between the main body of the damper means and the pivot portion, and pressing the main body to push the door upward through the main body of the damper means when the door is closed. Lifting means provided with the shaft and the shaft support so that when the door is closed and the door is pushed upward by the lifting means, the urging force of the urging member is not applied to the shaft of the damper means. An image forming apparatus comprising: releasing means for releasing the engagement of the image forming apparatus. 3. The method according to claim 2, wherein the release unit is formed on the shaft support, and is configured to engage with an engagement shaft provided at a lower end of a shaft of the damper unit.
An engagement groove having a non-acting portion that does not apply the urging force of the urging member to the shaft, and when the door is closed, the engaging shaft of the shaft is moved to the non-acting portion of the engagement groove. The image forming apparatus according to claim 2, wherein the image forming apparatus is configured to be moved. 4. The release means is provided on the door,
When the door is closed, a regulating member is provided which abuts on the upper end of the shaft and moves the shaft downward so as to move the engagement shaft of the shaft to the non-operating portion of the engagement groove. The image forming apparatus according to claim 2, wherein: 5. The damper means is provided on the shaft, and is provided on the body of the damper means so as to move an engagement shaft of the shaft to a non-operating portion of the engagement groove when the door is closed. The image forming apparatus according to claim 2, further comprising a contact portion configured to contact and move the shaft downward. 6. The image forming apparatus according to claim 1, wherein the door has a conveyance path for conveying a sheet. 7. The image forming apparatus according to claim 6, wherein the door has a switching unit for switching the transport path.