JP2930332B2 - Vertical split type image forming apparatus - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical split type image forming apparatus, and more particularly, to a vertical split type image forming apparatus having a registration roller for feeding a sheet to an image forming unit at a predetermined timing. Related to the device.

[Conventional technology and its problems]

2. Description of the Related Art An image forming apparatus, for example, a copying machine generally includes an image forming unit including a photosensitive drum and the like, and a registration roller for supplying a sheet to the image forming unit at a predetermined timing. In this type of image forming apparatus, there is an image forming apparatus in which a case for storing an image forming unit and a registration roller can be divided into upper and lower parts in consideration of convenience of maintenance work and the like.

In such a split type image forming apparatus, when the case is in the split state, the pair of registration rollers is separated into an upper side and a lower side. And the next time you combine the cases,
The separated connecting gears mesh with each other. However,
During the meshing operation of the gears, the tooth tips of the gears may come into contact with each other and a normal meshing may not be obtained. In this case, a gap is generated between the pair of registration rollers, and the leading end of the sheet supplied to the registration rollers during the copying operation enters between the registration rollers. For this reason, even if the registration roller starts supplying the paper to the image forming unit at a normal timing, the actual supply timing of the paper to the image forming unit and the movement timing of the transfer image in the image forming unit are shifted. As a result, a normal image transfer operation cannot be performed.

Conventionally, in order to solve such a problem due to the contact between the gear tips, it is generally practiced to once operate the drive source of the entire machine in advance, or to sharpen the gear tips which are problematic. Have been done. However, such a solution cannot solve the problem caused by the contact between the tooth tips of the gears in the registration roller. This is because a clutch is interposed between the registration roller and the driving source, and the clutch is normally in a disconnected state. For this reason, even if the drive source of the entire copying machine is operated, the registration roller does not rotate. In addition, when the tooth tip of the gear is deformed, the drive transmission of the gear slightly varies, so that it cannot be used for a registration roller that requires accurate sheet feeding timing.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a vertical split type image forming apparatus which can solve the problem caused by the contact between the tooth tips of the gears of a registration roller and can always supply a sheet to an image forming section at accurate timing. is there.

[Means for solving the problem]

A vertical split type image forming apparatus according to a first aspect of the present invention includes a case in which a multi-end side can be opened and closed in a vertical direction with a hinge portion at one end as a fulcrum, an image forming unit disposed in the case, and a pair of registration rollers. , A gear, and a gear rotating mechanism. The pair of registration rollers are in pressure contact with each other when the case is in the closed state and are separated from each other when the case is in the open state, and supply the sheet to the image forming unit at a predetermined timing. The gear is fixed to the registration rollers and connects the registration rollers to each other. The gear rotation mechanism rotates the gear based on the closing operation of the case when the case changes from the open state to the closed state.

A vertical split type image forming apparatus according to a second aspect of the present invention includes a case in which a multi-end side can be opened and closed in a vertical direction with a hinge part at one end as a fulcrum, an image forming unit disposed in the case, and a pair of registration rollers. , Gears, and registration roller temporary driving means. The pair of registration rollers are in pressure contact with each other when the case is in the closed state and are separated from each other when the case is in the open state, and supply the sheet to the image forming unit at a predetermined timing. The gear is fixed to the registration rollers and connects the registration rollers to each other. The registration roller temporary driving means drives the registration roller before the paper is supplied to the registration roller after the case is changed from the open state to the closed state.

[Action]

(1) In the vertical split type image forming apparatus according to the first invention, the registration roller supplies the sheet to the image forming section at a predetermined timing. The image forming unit performs an image forming process on the supplied paper.

At the time of maintenance or the like, the case is opened. In this case, with the division of the case, the pair of registration rollers and the rollers fixed thereto are also separated vertically. Next, when the case is closed, the gear rotation mechanism rotates the gear based on the closing operation of the case. As a result, the gear attached to the registration roller rotates, and a normal meshing state is established. That is, even if the gear fixed to the registration roller abuts on the tooth tips, the gears are rotated by the gear rotation mechanism, so that both gears mesh normally. As a result, the registration roller is normally brought into the pressure contact state, and the function of aligning the leading edge of the sheet is normally performed.

(2) In the vertical split type image forming apparatus according to the second invention, the registration roller supplies the sheet to the image forming section at a predetermined timing. The image forming unit performs an image forming process on the supplied paper.

At the time of maintenance or the like, the case is opened. In this case, with the division of the case, the pair of registration rollers and the rollers fixed thereto are also separated vertically. Next, after the case is closed, the registration roller temporary driving unit drives the registration roller before the paper is supplied to the registration roller. As a result, the gear attached to the registration roller rotates, and a normal meshing state is established. That is, even if the gears fixed to the registration rollers abut against each other at the tooth tips, the gears are rotated by the registration roller temporary driving unit, and the two gears normally mesh with each other. As a result, the registration roller is normally brought into the pressure contact state, and the function of aligning the leading edge of the sheet is normally performed.

〔Example〕

FIG. 1 shows a copying machine according to an embodiment of the present invention.

In FIG. 1, a document table 2 is fixed on an upper surface of a copying machine main body 1, and a document holder 3 is provided on the document table 2 so as to be openable and closable. Paper feed cassettes 4 and 5 are detachably mounted on the right side of the copying machine body 1 in the figure. On the left side of the main body 1 of the copying machine, a paper discharge tray 6 for discharging copied paper is mounted.

Inside the copier body 1, an exposure device 7 for reading an original is provided above the copier body 1. The exposure device 7 includes a light source, a mirror, a lens unit, and the like. A photosensitive drum 8 on the surface of which an electrostatic latent image is formed is arranged at the center of the copying machine body 1.
Around the photosensitive drum 8, a charging device 9, a developing device 10,
A transfer device 11, a paper separating device 12, and a cleaning device 13 are sequentially arranged.

A paper feed path 14 for feeding paper is provided between the paper feed cassettes 4 and 5 and an image forming unit including the photosensitive drum 8 and the like. Further, between the image forming section and the paper discharge tray 6, a paper discharge conveyance path 15, a fixing device 16 for fixing a transferred image on the paper, and a discharge roller 17 are arranged.

The copying machine main body 1 is composed of a main body upper part 1a and a main body lower part 1b. The main body upper portion 1a and the main body lower portion 1b are rotatably connected via a hinge 18 on the right side in the figure. As a result, the upper part 1a of the main body can be turned upward and opened as shown in FIG. 2 with respect to the lower part 1b of the main body. The second
As is apparent from the figure, the photosensitive drum 8 and the developing device 10
Each member disposed above the upper part belongs to the main body upper part 1a. Further, the transfer device 11, the fixing device 16, etc.
Belongs to The upper half of the paper feed path 14 belongs to the upper body 1a, and the lower half belongs to the lower body 1b.

The paper feed path 14 is mainly composed of a pair of plate-shaped members that are vertically spaced from each other. A pair of registration rollers 20 for transporting a sheet at a predetermined timing to an image forming unit including the transfer device 11 and the like are disposed at an end of the paper feed path 14 on the transfer device 11 side. Also, a registration roller
On the upstream side of the paper feed path 20, two
A pair of transport rollers 21 are arranged. Each of these rollers 2
0,21, the upper roller belongs to the main body upper part 1a,
The lower roller belongs to the lower body 1b.

As shown in FIG. 3, the registration roller 20 is mainly composed of a pair of upper and lower rollers 22,23. The upper roller 22 has a smooth metal surface on which the paper slips easily. On the other hand, the surface of the lower roller 23 is made of an elastic member and is normally pressed against the roller 22. Roller 22
Is rotatably supported by the upper body part 1a (FIG. 1) and is supported so as to be able to move slightly up and down. Further, the roller 22 is elastically urged downward by an urging mechanism (not shown). Central axis 22 of roller 22
A gear 24 is fixed to the left end of FIG. On the other hand, the lower roller 23 is rotatably supported by the lower part 1b of the main body. A gear 25 that meshes with the gear 24 is fixed to the central shaft 23a at the left end of the roller 23 in FIG. Further, a pinion 26 is attached to the left end of the central shaft 23a via a one-way clutch 27. As shown in FIG. 4, a rack 28 extending from above to below meshes with the pinion 26. The upper end of the rack 28 is supported by the upper body 1a (FIG. 1). further,
A guide roller 29 is in contact with the rear surface of the rack 28.
The guide roller 29 is rotatably supported by a support member 30 fixed to the lower portion 1b of the main body (FIG. 1). The rack
An inclined surface 28a is formed at the rear end of the rear surface 28.

3, a clutch 31 and a gear 32 are provided at the right end of the center shaft 23a of the roller 23 in FIG. A drive source 51 including a motor and the like is connected to the gear 32 via a gear group 50. As shown in FIG.
The roller 32 is rotatably supported by the center shaft 23a of the roller 23. A friction plate 33 rotatably supported by the central shaft 23a is disposed on the right side of the gear 32 in the figure. The friction plate 33 and the gear 32 are connected by an elastic plate 34, and the friction plate 33 is an elastic plate.
The gear 34 is constantly biased toward the gear 32 side. The clutch plate 35 concentrically opposed to the friction plate 33 has a rotating shaft.
It is integrally supported by 23a. An electromagnetic actuator 36 is rotatably fitted to the boss of the clutch plate 35. The electromagnetic actuator 36 is prevented from rotating by a stopper 38 fixed to a wall plate 37 of the lower part 1b of the main body.

 Next, the operation of the above embodiment will be described.

During normal copying operation, the upper part 1a and the lower part
1b are combined as shown in FIG. As a result, the transfer device 11 and the photosensitive drum 8 are adjacent to each other, and the paper feed conveyance path 14 is combined in a transportable state. In this state, when the paper is conveyed from the registration roller 20 to the transfer device 11 at a predetermined timing, the electromagnetic actuator 36 of the clutch 31 shown in FIG. 3 is operated to bring the clutch 31 into the connected state. As a result, the rollers 22 and 23 rotate to convey the sheet to the transfer device 11 side. In addition, a pair of gears 24, 25
Is provided to ensure accurate conveyance of the sheet by the rollers 22 and 23. As a result, the rollers 22 and 23 can accurately transport the sheet without causing slippage.

As described above, the predetermined sheet supplied from the sheet feeding cassettes 4 and 5 through the sheet feeding path 14 is conveyed to the transfer device 11 side by the registration roller 20, and is placed on the document table 2 by the exposure device 7. The image information of the placed document is read. The read image information is formed on the photosensitive drum 8 as an electrostatic latent image. The photoconductor drum 8 is developed in the developing device 10, and the obtained toner image is transferred to a sheet in the transfer device 11. The paper on which the image has been transferred is
Is discharged onto the paper discharge tray 6 after the fixing process.

Next, the upper part 1a of the main body may be opened upward around the hinge part 18 as shown in FIG. 2 for maintenance work or the like. In this case, the transfer device 11 transfers the photosensitive drum 8
Are separated from each other, and the sheet feeding conveyance path 14 is also vertically separated. Accordingly, each pair of rollers 20, 21 is also separated from each other. As a result, as shown in FIGS. 6 and 7, the rollers 22 and 23 of the registration roller 20 are separated, and at the same time, the gears 24 and 25 are disengaged. In addition, this body upper part 1
The rack 28 rotates the pinion 26 in accordance with the upward rotation of “a”, but in this case, the one-way clutch 27 operates, and the roller 23 is not driven.

After maintenance work, etc.,
When combining the main body upper part 1a and the main body lower part 1b as shown in the figure, the main body upper part 1a is rotated downward about the hinge part 18. As a result, the copying machine is brought into the state shown in FIG. Here, the rack 28 meshes with the pinion 26 before the rollers 22 and 23 come into contact with each other. At this time, the inclined surface 28a (FIG. 4) of the rack 28 first contacts the guide roller 29, and the rack 28 is pressed against the pinion 26 by the guide roller 29. The downward movement of the rack 28 rotates the pinion 26, and accordingly, the roller 23 and the gear 25 also rotate. For this reason, even if the gear 24 and the gear 25 are in a positional relationship such that the tooth tips come into contact with each other, as a result of the rotation of the gear 25, the two gears 24, 25 are arranged at the normal meshing position. Therefore, since the gears 24 and 25 are always set in a normal meshing state, a gap does not occur between the rollers 22 and 23.

Next, when the copying operation is performed again, the paper
Even if the sheet is conveyed to the registration roller 20, the roller 22 and the roller 23 are surely in pressure contact with each other, so that the leading edge of the sheet can be accurately aligned. Therefore, the registration roller 20 always moves the transfer device 11
Paper can be transported to the side.

[Other embodiments]

(A) Instead of the embodiment shown in FIG. 4, the configuration shown in FIG. 8 can be adopted.

In FIG. 8, the rack 40 that meshes with the pinion 26 is configured to be long, and the rack 40 is always maintained in a state of meshing with the pinion 26 even if the upper body 1a is opened upward as shown in FIG. . Also in this case, the main body upper part 1a
When the gear is closed, the gears 24 and 25 assume a normal meshing posture by the rotation of the pinion 26 by the rack 40.

(B) The present invention can be implemented in the same manner by performing control as shown in FIG. 9 instead of the configuration of the combination of the pinion 26 and the racks 28 and 40.

In FIG. 9, if a main switch (not shown) is turned on, initial settings such as setting the number of copies to one in step S1 are performed. In step S2, it is determined whether the print key has been pressed. If the print key has not been pressed, the process shifts to step S3 to perform another process based on input information from another input key or a sensor. Upon completion of the process in the step S3, the process returns to the step S2.

If the print key is pressed, the process moves to step S4. In step S4, a command is issued to start the sequence of the copy operation. Thus, a series of copying operations such as the start of rotation of the driving source 34 starts. Next, in step S5, the electromagnetic actuator 36 of the clutch 31 is operated for a short period of time to bring the clutch 31 into the connected state. Thus, the gear 25 is driven to rotate. Therefore, if the upper part 1a of the main body is temporarily opened and closed before the printing operation,
Even if 25 and 25 are in contact with each other, both gears 24, 25
The engagement between them is surely returned to normal. Next, the developing device
Other processes such as checking the toner density in the printer 10 and checking the temperature in the fixing device 16 are performed in step S6. Then, while performing these processes, the process waits for the end of the copy operation in step S7. Upon completion of the copy operation, the process returns from the step S7 to the step S2.

In this case, without using the racks 28 and 40 and the pinion 26, the gear 2
The engagement of 4,25 can be made normal.

(C) Instead of the embodiment of (b), the main body upper part 1a is detected to be closed after being opened,
The gear 31 and the gear 25 may be brought into a normal state by setting the gear 31 in a connected state. In this case, the contact state between the tips of the gears 24 and 25 does not remain for a long time, so that the deformation of the gears 24 and 25 can be prevented. However, upper body 1
When a is closed, it is necessary to operate the drive source 34 and the clutch 31 specially.

〔The invention's effect〕

(1) A vertical split type image forming apparatus according to a first aspect of the present invention includes:
Since the gear has a gear rotating mechanism that rotates the gear based on the closing operation of the case, the gear meshes normally without the tooth tips remaining in contact. As a result, the paper transport timing by the registration rollers is always accurately maintained.

(2) A vertical split type image forming apparatus according to a second aspect of the present invention,
The provision of the registration roller temporary driving means for driving the registration roller prior to the supply of the sheet to the registration roller ensures that the gears normally mesh at least before the sheet is supplied to the registration roller. Therefore, at least when the paper is supplied to the registration rollers, the rollers 22, 2
3 is in contact in a normal state, and the timing of transporting the sheet by the registration roller is always accurately maintained.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of one embodiment of the present invention, FIG. 2 is a schematic longitudinal sectional view showing an operation state thereof, FIG. 3 is a partial side view of a registration roller portion, and FIG. FIG. 5 is a vertical sectional view of a clutch part, and FIGS.
FIG. 8 is a diagram corresponding to FIGS. 3 and 4 in the state of FIG. 2, FIG. 8 is a diagram corresponding to FIG. 7 of another embodiment, and FIG. 9 is a control flowchart of still another embodiment. is there. 1 ... Copy machine body, 1a ... Upper body, 1b ... Lower body,
8 photosensitive drum, 11 transfer device, 20 registration roller, 22, 23 roller, 24, 25 gear, 26 pinion, 28, 40 rack, 31 clutch.

──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. ⁶ identification code FI G03G 15/00 526 G03G 15/00 526 21/14 21/00 372 (58) Investigated field (Int.Cl. ⁶ , DB name ) G03G 15/00 510-550 G03G 21/14-21/18 B65H 5/06 B65H 9/14

Claims (2)

(57) [Claims] 1. A case that is openable and closable on the other end side in a vertical direction with a hinge portion at one end as a fulcrum, an image forming unit disposed in the case, and a case where the case is brought into pressure contact with each other when the case is in a closed state. A pair of registration rollers for supplying paper to the image forming unit at a predetermined timing, which are separated from each other when the printer is in an open state, a gear fixed to the registration roller and connecting the registration rollers to each other, A vertically rotating image forming apparatus, comprising: a gear rotating mechanism that rotates the gear based on a closing operation of the case when the case changes from an open state to a closed state. 2. A case which is openable and closable on a multi-end side in a vertical direction with a hinge portion on one end side as a fulcrum, an image forming portion arranged in the case, and the case is pressed against each other when the case is in a closed state, and the case is A pair of registration rollers that are separated from each other when opened to supply paper to the image forming unit at a predetermined timing; a gear fixed to the registration rollers and connecting the registration rollers to each other; An upper / lower split type image forming apparatus comprising: a registration roller temporary driving unit that drives the registration roller before the sheet is supplied to the registration roller after the state is changed from the state to the closed state.