JPH08151166A - Sheet carrying device and image forming device - Google Patents

Abstract

PURPOSE: To facilitate the removal of a jam sheet, and downsize a device by interlocking a second frame body to move a sheet carrying part in the state where it is separated from a first frame body, and opening a second sheet carrying passage provided on the first frame body. CONSTITUTION: When a jam occurs, a body upper unit 200 as a second frame body is rotated around a hinge shaft 18 to a body lower unit 100 as a first frame body to open a carrying passage so as to check whether a paper is left on the carrying part 12 or fixing part 13 of a body as a first carrying passage or a resistor roller pair 5 or not. When it is judged that no paper is present in this area, consequently, a fixing inlet guide 29 integrally formed with the body carrying part is held to rotate the carrying part 12 in a direction A, and an intermediate tray upper guide part 16a is opened interlockingly with it. Since the rotating shaft of the carrying part 12 and the rotating shaft 21 of the intermediate tray upper guide 16a are situated on the same side as the rotating shaft 18 of the upper frame body 200, respectively, at that time, the removing work can be performed in one direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for conveying a sheet such as a paper in an image forming apparatus such as a copying machine or a laser printer, and more particularly, to an image formed on both sides of the sheet or on the same side of the sheet. The present invention relates to an image forming apparatus having an automatic double-sided device that separates sheets, which are once stacked in a sheet re-feeding unit, one by one and re-feeds them to the image forming unit.

[0002]

2. Description of the Related Art In recent years, from the viewpoint of environmental protection, many copying machines equipped with an automatic double-sided device have appeared on the market. The automatic double-sided device is important from the viewpoint of reducing paper consumption as much as possible, and has been installed as standard equipment not only in high-speed machines but also in slow-speed machines.

Further, from the viewpoint of easiness of jam processing work, a large number of copying machines of the crumbial type are on the market mainly for low speed machines. This divides the main body into an upper housing 200 and a lower housing 100, and opens the sheet conveyance path by opening the upper housing largely upward centering on the hinge on the right side of the main body, making it easy for foreigners with large hands. Since the paper can be removed, the cost of the machine can be reduced because the machine body can be downsized.

Therefore, for the purpose of utilizing the advantages of both, a copying machine of the clamshell type and equipped with an automatic double-sided copying apparatus has been considered.

A copying machine to which the present invention is applied will be described below.

FIG. 4 is a sectional view of a copying machine to which the present invention is applied. In FIG. 4, the sheets of paper, which are stacked on the middle plate 2 in the cassette 1, are pressed against the paper feed roller 3 by the middle plate, and the paper feed roller 3 and the separation pad 3 are pressed.
The upper sheet is separated by a and is conveyed to the register roller 5 by the conveying roller 4.

The leading edge of the paper is abutted against the nip portion of the pair of register rollers which are stopped and curved, and the skew is corrected.
The register roller 5 adjusts the resist in the vertical and horizontal directions.

The original image placed on the original glass 6 is illuminated by the illumination lamp 7 and is irradiated on the photosensitive drum 10 through the mirror 8, the lens 9 and the like to form a latent image. This latent image is converted into a toner image by the developing device 11.

The paper is sent out by the register roller 5 at a timing matched with the toner image, and the toner image is transferred onto the paper at a proper position by the transfer roller 19. The paper is further transported to the fixing device 13 by the transport belt 12 of the transport unit,
After the toner image is fixed on the paper by the fixing device 13, the paper is loaded from the paper discharge roller 14 onto a paper discharge tray (not shown).

Further, when automatic double-sided multiplexing is performed, the paper is not discharged and stacked on the paper discharge tray, and the paper is conveyed again to the image forming unit.

When forming images on both sides, the paper is conveyed by the paper discharge roller 14 which rotates in the forward direction until the rear end passes through the flapper 15, and the paper discharge roller 14 is rotated while the paper is being held. The normal rotation is changed to the reverse rotation, the paper is switched back, and the flapper 15 of the paper discharge unit switches the traveling direction of the paper and the paper is conveyed to the intermediate tray 16.

When multiplexing is performed, the flapper 15 in the paper discharge unit switches the traveling direction of the paper, and the intermediate tray 16 located on the lower side of the main body while the leading edge of the paper remains unchanged.
Transported to

The conveyed sheets are temporarily stacked and held on the intermediate tray 16, and are re-fed by a re-feeding roller 17 and a re-conveying roller 20.
Is conveyed again to the registration roller.

Then, the vertical and horizontal resists are adjusted again,
After the image formation by the same process as the first side, it is ejected to the paper ejection tray.

Further, the copying machine to which the present invention is directed has a clamshell structure, and as shown in FIG. 5, by rotating upward about a hinge shaft 18, an image forming portion, a conveying portion,
It is possible to open the fixing unit, which allows processing when a paper jam occurs.

[0016]

When a jam occurs in the copying machine having such a structure, the conventional copying machine opens a front cover (not shown) on the front side of the main body as shown in FIG. Then, the lock is released and the upper frame 200 of the main body is rotated upward to remove the jammed paper on the main body transport unit 12 or the entrance of the fixing unit 13, and it remains in the intermediate trays 16 on both sides. The paper was designed to be removed from the front side of the main body by hand.

FIG. 5 shows a state in which the upper guide member 16a of the intermediate tray 16 is released when removing the paper from the intermediate tray. The upper guide member 16a is centered on a hinge on the back side of the main body (not shown). It is designed to rotate.

However, this configuration has the following contradiction. While the upper part of the main body is made into a clamshell system to reduce the size of the main body of the machine and improve the workability of jam handling, the intermediate tray located at the lower part of the main body transport section 12 and above the paper feed cassette 1 In order to remove the paper on the sheet 16, it is necessary to insert a hand from the front side into the inside of the main body, so that a large space is required for jam clearance.

In recent years, when the use of recycled paper is rapidly increasing, the number of machines that carry paper according to the central standard is increasing from the viewpoint of improving the paper carrying property. With this construction,
In order to remove the small size paper, it is necessary to insert a hand even to the center of the main body, and it is necessary to take a large space between the main body transport section and the intermediate tray. As a result, even if the clamshell method is adopted, the height of the machine body will be high.

Further, in recent years, options such as a paper deck and a multi-stage cassette pedestal have been considered in order to save the trouble of paper replenishment and to enable automatic feeding of papers of various sizes. Since it is installed at the bottom of the main body, the height of the main body tends to be higher and higher. However, if the height of the main body is too high, there is a possibility that the operation of the keys on the operation unit located at the top of the main body may be hindered and the workability when closing the upper unit of the main body may be deteriorated.

If the hand is inserted deep inside the body, unnecessary parts may be touched, which may cause a machine failure, or the edge of the sheet metal may injure the hand.

[0022]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet conveying device or an image forming apparatus in which a jam sheet can be easily removed and the size can be reduced.

The structure of the present invention for achieving the above object is the sheet conveying apparatus which can open the first sheet conveying path by separating the second frame from the first frame. A sheet conveyance unit that conveys a sheet along a sheet conveyance path is movably provided in the first frame body, and the sheet conveyance unit is moved in a state where the second frame body is separated from the first frame body. The sheet transporting device is configured such that, when moved, the second sheet transporting path provided in the first frame is opened in association with the movement of the sheet transporting unit.

Alternatively, according to the present invention, a unit relating to image formation is provided in the upper frame of the main body, and the paper after the image formation is re-fed to the lower frame of the main body is re-fed to the unit relating to image formation. Equipped with other units, including means,
The upper frame of the main body has a clamshell structure that is rotatably locked around a point of the lower frame, and the lower frame is provided with a conveyance unit that conveys the paper to the fixing device and a position below the conveyance unit. In an image forming apparatus having an intermediate tray for holding paper for stacking and re-feeding paper for double-sided multiplexing, the transport unit has a rotation center on the side where the rotation center of the upper frame exists. On the intermediate tray, which is held in the main body and is rotatably locked in the same direction as the opening direction of the upper frame body and which has a rotation center in the same direction as the transport unit in conjunction with the opening operation of the transport unit. By providing the image forming apparatus characterized in that the guide member rotates in the upward direction, it is possible to provide the user with a copying machine having better operability.

[0025]

Embodiments will be described in detail below based on specific embodiments. FIG. 1 is a sectional view of a copying machine showing a specific embodiment of the present invention.

In FIG. 1, the middle plate 2 in the cassette 1 is shown.
A sheet of paper stacked on the sheet is pressed by the sheet feeding roller 3 by the intermediate plate, the upper sheet is separated by the sheet feeding roller 3 and the separating pad 3a, and the conveying roller 4 registers the register roller 5 Be transported to.

The leading edge of the paper is abutted against the nip portion of the pair of register rollers which are stopped and curved, and the skew is corrected.
The register roller 5 adjusts the resist in the vertical and horizontal directions.

The original image placed on the original glass 6 is illuminated by the illumination lamp 7 and is irradiated on the photosensitive drum 10 through the mirror 8, the lens 9 and the like to form a latent image. This latent image is converted into a toner image by the developing device 11.

The paper is sent by the register roller 5 at a timing matched with the toner image, and the toner image is transferred to the paper at a proper position by the transfer roller 19. The paper is further transported to the fixing device 13 by the transport belt 12 of the transport unit,
After the toner image is fixed on the paper by the fixing device 13, the paper is loaded from the paper discharge roller 14 onto a paper discharge tray (not shown).

Further, when automatic double-sided multiplexing is performed, the paper is not discharged and stacked in the paper discharge tray, and the paper is again loaded on the photosensitive drum 10.
The sheet is conveyed to an image forming unit or an image forming unit including the transfer roller 19, the developing device 11, and the like.

When forming images on both sides, the paper is conveyed by the paper discharge roller 14 rotating in the forward direction until the trailing edge passes the flapper 15, and the paper discharge roller 14 is rotated while the paper is being held. The normal rotation is changed to the reverse rotation, the paper is switched back, and the flapper 15 of the paper discharge unit switches the traveling direction of the paper and the paper is conveyed to the intermediate tray 16.

When multiplexing is performed, the flapper 15 in the paper discharge unit switches the traveling direction of the paper, and the intermediate tray 16 located on the lower side of the main body with the leading edge of the paper unchanged.
Transported to

The conveyed sheets are once stacked and held on the intermediate tray 16 and are conveyed again to the registration rollers by the sheet re-feeding roller 17.

The intermediate tray 16 and the transport paths before and after it form a second transport path.

Then, the vertical and horizontal resists are adjusted again,
After the image formation by the same process as the first side, it is ejected to the paper ejection tray.

The main body of the present copying machine is different from that of the copying machine shown in FIG. 4, and the copying machine of the present invention is small. This is because the space between the main body transport unit 12 and the intermediate tray 16 is narrow, and it can be seen that the transport roller 20 that was present in the configuration of FIG. This is because the height of the machine body has been reduced, and even if a small size paper is conveyed, the register roller can be sufficiently reached without the roller 20.

Further, although the upper guide 16a of the intermediate tray 16 of the conventional copying machine is the hinge on the back side of the main body, the present invention is 21 in FIG. 1, whereby the left side of the upper guide 16a is centered around this point. The area is released.

Optical systems 7-9, photosensitive drum 10, developing device 1
The upper frame 2 of the main body is a unit related to image formation including 1 and the like.
00, and another unit including a re-feeding unit including an intermediate tray 16 and a re-feeding roller 17 for re-feeding the image-formed paper on the lower frame 100 of the main body to the unit related to the image formation. The upper frame of the main body has a clamshell structure in which the upper frame is rotatably locked around one point of the lower frame, and the lower frame 100 has a transport unit 12 for transporting paper to the fixing device and the transport unit 12. It has an intermediate tray 16 for holding paper for stacking and re-feeding paper, which is located at the lower part of the unit and is double-sided.

The carrying section 12 has a rotation center 22 in the lower body on the side where the rotation center 18 of the upper frame 200 is present, and is rotatably locked in the same direction as the opening direction of the upper frame 200. There is.

First, when a jam occurs, in order to check whether or not any paper remains on the transport unit 12 of the main body as the first transport path, around the fixing unit 13, or around the register roller pair 5, As shown in 1, the first frame body,
Alternatively, with respect to the main body lower unit 100 as a lower frame, the upper unit 20 as a second frame or an upper frame is provided.
0 is rotated about the hinge shaft 18 to open the transport path.

In this state, there is basically no difference from the conventional machine. However, if the user determines that there is no paper in this area, then the carrying section 12 is rotated in the direction of arrow A in FIG. 2 with the fixing entrance guide 29 integrally formed with the main body carrying section 12. Interlocking with this, the intermediate tray upper guide portion 16a is opened.

FIG. 3 shows the main body transport section 12 and the intermediate tray 1.
6 illustrates an interlocking system with the upper guide 16a of No. 6 of FIG.

The driving force of the main body transport unit 12 is supplied from the main body via the shaft 22. Further, the shaft 22 is rotatably locked to the side plate of the main body of the copying machine, and when the drive is cut off by the clutch 23, the shaft is configured to be freely rotatable.

As shown in FIG. 3, a clutch 23 is attached to the shaft 22.
If the driving force is transmitted from the driving gear 23 via the clutch gear 23a, the shaft 22 can freely rotate when the clutch 23 is disengaged. The drive gear 24 is a gear that is rotated by a motor (not shown) of the main body, and constantly rotates when the motor rotates.

A pulley 25 is fixed to the shaft 22 so as to rotate together with the shaft 22, and the driving force is applied to the conveyor belt 2.
6 can be transmitted. The shaft 27 is a driven pulley shaft. The fixing entrance guide 29, which is integrally formed with the transport base 28, has a U-shaped notch 30 in the center, and the user can hold the portion to open the transport unit in the direction of arrow B.

Next, in the upper guide 16a of the intermediate tray 16, an upper roller 31 for conveying double-sided paper is pressure-held by a leaf spring 32 or the like, and a magnet 33 provided on the surface of the lower conveyance guide 16 not shown. The upper guide 16a is magnetically held by the lower conveyance guide 16. In this state, when the user holds the cutout portion 30 of the fixing entrance guide 29 to open the transport unit, the two links 34 connecting the transport unit 12 and the upper guide 16a also rotate the upper guide unit 16a. The link 34 includes the transport base 28 and the upper guide 16a.
It is rotatably locked with respect to. Further upper guide 16
The a is locked so as to be rotatable around the shaft 21.

The user lifts the conveying section 12 upward against the magnetic force of the magnet 33. This allows one hand to lift the transport and the other hand to handle the jammed paper.

The open state of the main transfer section may be maintained by the free stop of the transfer section 12, in which case the main transfer section 12 and the main transfer section 12 are interlocked with the closing operation of the upper unit 200. If the intermediate tray upper guide 16a can be closed, the jam handling workability is further improved.

In the above-described embodiment, since the rotary shaft 22 of the transport section 12 and the rotary shaft 21 of the intermediate tray upper guide 16a are on the same side as the rotary shaft 18 of the upper frame body 200, the jam sheet removing operation is not necessary. Since it can be performed from the direction, the jam sheet removing operation becomes easy.

[0050]

As described above, according to the present invention, the size of the device is reduced, the cost is reduced, and the user is provided with a device with good operability such as easy opening and closing work of the upper unit of the main body. You can do it. Also, it becomes easy to remove jammed paper.

[Brief description of drawings]

FIG. 1 is a sectional view showing a state in which an upper main body of a copying machine showing a specific embodiment of the present invention is opened.

FIG. 2 is a cross-sectional view showing a state in which an opening operation of an upper guide of an intermediate tray is performed in conjunction with a releasing operation of a main body transport section.

FIG. 3 is a perspective view for specifically explaining the interlocking of the main body transport section and the intermediate tray upper guide.

FIG. 4 is a sectional view for explaining the function of the copying machine to which the present invention is applied.

FIG. 5 is a cross-sectional view illustrating a jam processing method of a conventional copying machine.

[Explanation of symbols]

 1 Cassette 10 Photosensitive Drum 11 Developing Device 12 Conveying Section 16 Intermediate Tray 16a Upper Guide 17 Refeed Roller 100 Lower Frame 200 Upper Frame

Claims (8)

[Claims] 1. A sheet transporting device capable of opening a first sheet transport path by separating a second frame body from a first frame body, in which a sheet is transported along the sheet transport path. In a state in which the transport unit is movably provided on the first frame body and the second frame body is separated from the first frame body,
When the sheet conveying section is moved, the second sheet conveying path provided in the first frame body is opened in association with the movement of the sheet conveying section. apparatus. 2. The sheet conveying apparatus according to claim 1, wherein the second frame body is rotatably supported by the first frame body. 3. The sheet conveying device according to claim 1, wherein the sheet conveying portion is rotatably supported by the first frame body. 4. The sheet conveying apparatus according to claim 1, wherein the second sheet conveying path guides the sheet that has passed through the first sheet conveying path to the first sheet conveying path again. 5. The sheet conveying apparatus according to claim 1, further comprising an image forming unit that forms an image on a sheet passing through the first conveying path. 6. Another unit including an image forming unit on the upper frame of the main body, and a re-feeding unit for re-feeding the paper on the lower frame of the main body after image formation to the unit related to image formation. The upper frame of the main body has a clamshell structure in which the upper frame is rotatably locked around one point of the lower frame, and the lower frame has a transport unit for transporting paper to the fixing device and the transport unit. In an image forming apparatus configured to have a middle tray that holds paper for stacking and re-feeding paper because it is located at the lower part of the upper side and is on the side where the rotation center of the upper frame is present. An image forming apparatus characterized in that the lower main body has a rotation center and is rotatably locked in the same direction as the opening direction of the upper frame. 7. The upper guide member of the intermediate tray, which has a rotation center in the same direction as the transport unit, rotates upward in association with the opening operation of the transport unit. Image forming device. 8. The image forming apparatus according to claim 7, wherein there is a link member that is rotatably engaged with each of the transport section and the intermediate tray upper guide section.