JPH06250456A - Image forming device - Google Patents

Abstract

PURPOSE:To miniaturize paper feeding units having plural paper feeding means and to improve tree positioning accuracy of the paper feeding means with respect to an image forming part. CONSTITUTION:The frame bodies A and B of an image forming device main body 100 are vertically parted, positioning means 81 and 82 and a drive source 71A are supported by the upper frame body A and respective paper feeding units 41 and 42 are driven by the drive source 71A. Thus, respective paper feeding units 41 and 42 can be miniaturized and simultaneously, an image forming device improving the positioning accuracy of each paper feeding unit and composed of different paper feeding means can be easily obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, an LBP and a printer, and more particularly to a unit structure of a paper feeding means.

[0002]

2. Description of the Related Art Conventionally, even if an image forming apparatus has a plurality of paper feeding means, all of the plurality of paper feeding means are constructed as one unit, or all of the paper feeding means are provided. It was configured as a separate unit, each positioned on the body.

[0003]

However, in the above-mentioned conventional example, since the plurality of sheet feeding means are constituted as one unit, the weight of the unit becomes large and the whole unit becomes large, and therefore, the factory or the market. There was a drawback that the workability in the service was not good.

In addition to the common main body configuration, it has different functions such as normal cassette paper feeding, paper feeding by a paper deck capable of stacking a large amount of copy paper, and refeeding for double-sided copying. When forming a product group that is configured by mixing sheet feeding means, it is necessary to make different sheet feeding units for each combination of various sheet feeding means, which increases costs and complicates management in the manufacturing process. There was a problem such as.

Further, when all of the plurality of sheet feeding means are constructed as separate units, the positional accuracy between the respective units is lowered, and especially the frame body of the image forming apparatus main body is divided and constructed. In that case, there is a drawback that the positional accuracy between the image forming unit and the paper feeding unit is lowered.

Further, there is a drawback that the drive input or drive input section on the main body side is complicated because it is necessary to input the drive independently for each paper feeding unit.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image forming apparatus in which a paper feeding unit having a plurality of paper feeding means is downsized and the positioning accuracy of the paper feeding means with respect to an image forming portion is improved. is there.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and includes at least two or more paper feed cassettes arranged vertically in an image forming apparatus main body.
An upper frame body having at least two sheet feeding means for feeding the sheets in each of the sheet feeding cassettes to the image forming section, and the frame body constituting the image forming apparatus supports the image forming section and the upper frame body. In an image forming apparatus including a lower frame member that is a member different from the body, and at least one sheet feeding cassette is supported by the lower frame member, the sheet feeding unit is arranged on the upstream side in the sheet conveying direction. The sheet feeding unit is divided into a first sheet feeding unit and a second sheet feeding unit arranged on the downstream side in the conveying direction, and each sheet feeding unit is positioned in the frame body by a common positioning unit, and the positioning unit. Is provided on an upper frame member that supports the image forming unit among the frame members that form the main body.

Further, a part of the sheet conveying path extending from the sheet feeding means to the image forming portion is configured to be openable and closable, and the sheet conveying path extends between the first sheet feeding unit and the second sheet feeding unit. The guide member constituting the above is rotatably attached to the first paper feeding unit.

Further, the first sheet feeding unit and the second sheet feeding unit are driven by one driving source provided in the image forming apparatus main body, and the first and second sheet feeding units are driven from the driving source. The drive input is input to only one of the sheet feeding units and the drive is transmitted to the other between the sheet feeding units.

The drive source and its drive output section are
It is characterized in that it is arranged in an upper frame member that supports the image forming unit among the frame members that constitute the main body of the image forming apparatus.

Further, the image forming apparatus comprises at least one paper feed cassette disposed in the main body of the image forming apparatus, and at least one paper feed means for feeding the sheets in the paper feed cassette to the image forming unit. The frame forming the image forming apparatus includes an upper frame supporting the image forming unit and a lower frame separate from the upper frame, and the upper frame supports at least one sheet feeding cassette. In the image forming apparatus, the paper feeding unit is
A sheet feeding unit supported by an upper frame member that supports the image forming unit among the frame members that form the image forming apparatus main body, and a guide member that forms a sheet conveying path across both the frame members are rotatable. And a door unit that is pivotally supported on the sheet feeding unit and the door unit, and the sheet feeding unit and the door unit are positioned on the frame by a common positioning unit, and the positioning unit supports the image forming unit of the frame. It is characterized in that it is arranged on the upper frame.

[0013]

The sheet is fed from any of the plurality of first and second sheet feeding units provided in the upper frame body and the lower frame body which constitute the main body of the image forming apparatus, and the sheet is fed to the image forming unit. Be delivered. Each sheet feeding unit is positioned on the frame by a common positioning unit, and the positioning unit is arranged on the upper frame supporting the image forming unit. As a result, it is possible to reduce the size of the paper feeding unit, improve the positioning accuracy of the plurality of paper feeding units with respect to the image forming unit, and realize a combination of various paper feeding units.

Further, the driving of the first and second paper feeding units is driven by one drive source and its drive output section provided in the main body of the image forming apparatus, and the drive source and drive output section are driven by the image. It is arranged on the upper frame that supports the forming portion. This simplifies the configuration of the driving device that drives the paper feeding unit, and can easily cope with various combinations of paper feeding units.

[0015]

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

FIG. 2 is a schematic sectional view of a color image forming apparatus according to the embodiment of the present invention.

This example has a digital color image reader section in the upper part and a digital color image printer section in the lower part.

In the reader unit, the original 30 is placed on the original table glass 31 and is exposed and scanned by the exposure lamp 32, whereby the reflected light image from the original 0 is condensed by the lens 3 to the full color sensor 4 to obtain the color color. Obtain a decomposed image signal. The color-separated image signal is processed by a video processing unit (not shown) through an amplifier circuit (not shown), and is sent to the printer section.

In the printer section, the photosensitive drum 1 as an image carrier is rotatably supported in the direction of the arrow, and a pre-exposure lamp 11, a corona charger 2, a laser exposure optical system, and a potential sensor 12 are provided around the photosensitive drum 1. , Four developing devices 4y, 4c, 4m, 4Bk of different colors, on-drum light amount detecting means 1
З Place a transfer device and a cleaning device.

In the laser exposure optical system 3, the image signal from the reader section is converted into an optical signal by a laser output section (not shown), and the converted laser light is reflected by the polygon mirror Зa, and the lens 3b and the mirror 3b. The image is projected on the surface of the photosensitive drum 1 through Зc.

During image formation in the printer section, the photosensitive drum 1
Is rotated in the direction of the arrow, and the photosensitive drum 1 after the charge is removed by the pre-exposure lamp 11 is charged in a negative direction by the charger 2, and the light image E is irradiated for each separated color to form a latent image.

Next, a predetermined developing device is operated to develop the latent image on the photosensitive drum 1 to form a resin-based toner image on the photosensitive drum 1. The developing device is an eccentric cam 24.
By the operations of y, 24c, 24m, and 24Bk, the photosensitive drum 1 is selectively approached according to each separated color.

Further, the toner image on the photosensitive drum 1 is
The recording material is transferred onto the recording material supplied from the recording material cassette 104 to the position facing the photosensitive drum 1 via the transfer system and the transfer device 5. In this example, the transfer device 5 includes a transfer drum 5a, a transfer charger 5b, an attraction charger c for electrostatically attracting a recording material, and an attraction roller 5g, an inner charger 5d, and an outer charger 5e. A recording material carrying sheet 5f made of a dielectric material is integrally stretched in a cylindrical shape in the peripheral opening area of the transfer drum 5a which is rotatably driven. The recording material carrying sheet 5f uses a dielectric sheet such as a polycarbonate film.

As the drum-shaped transfer device, that is, the transfer drum 5a is rotated, the toner image on the photosensitive drum is transferred by the transfer charger b onto the recording material carried on the recording material carrying sheet 5f.

In this way, a desired number of color images are transferred to the recording material that is adsorbed and conveyed to the recording material carrying sheet 5f to form a full color image.

In the case of full-color image formation, when the transfer of the four color toner images is completed in this way, the recording material is separated from the transfer drum 5a by the action of the separating claw 8a, the separating push-up roller 8b and the separating charger 5h, and the heat is generated. The sheet is discharged to the tray 10 via the roller fixing device 9.

On the other hand, after the transfer, the photosensitive drum 1 is subjected to the image forming process again after the residual toner on the surface is cleaned by the cleaning device 6.

When images are formed on both sides of the recording material,
After the fixing device 9 is discharged, the transport path switching guide 19 is quickly driven, and after being guided to the reversing path 2la through the transport vertical path 20, the reverse end of the reversing roller 2lb reverses the leading end when fed. Then, the paper is withdrawn in the direction opposite to the direction in which the paper was sent, and is stored in the intermediate tray 103. After that, an image is formed on the other surface by the above-described image forming step.

Further, in order to prevent the powder from being scattered and adhered on the recording material carrying sheet 5f of the transfer drum 5a and the oil being adhered to the recording material, the brush is provided via the fur brush 14 and the recording material carrying sheet 5f. 14, a backup brush 15 facing the sheet 14, an oil removing roller 16 and a recording material carrying sheet 5
Do not clean by the action of the backup brush 17 that faces the roller 16 via f. Such cleaning should be done before or after image formation, or jam (paper jam)
When it occurs, it will be done at any time.

Further, in this example, the eccentric cam 25 is operated at a desired timing and the cam follower 5i integrated with the transfer drum 5f is actuated so that the gap between the recording material carrying sheet 5a and the photosensitive drum 1 is reduced. The configuration can be set arbitrarily. For example, during standby or when the power is off, the transfer drum and the photosensitive drum are separated from each other.

Next, in the color image forming apparatus as described above, the part relating to the present invention will be described in detail.

In FIG. 2, the frame body which constitutes the main body of the image forming apparatus is separated from the dividing line D by an upper frame body A and a lower frame body B.
Can be divided into The upper and lower frames are respectively the upper front side plate A ₁ and the upper rear side plate A ₂ , the lower front side plate B ₁ and the lower front side plate B _2.
, Which are fixed on the bottom plate C and are supported by some stays. All of these are fixed by screws. Here, the main device forming the printer unit, the photosensitive drum 1, the developing device 4, the transfer device 5, the fixing device 9, and the like are all supported by the upper frame A.

In this embodiment, a total of five so-called sheet feeding devices are provided, and the sheet feeding cassette 1 dedicated to small size paper is provided.
04, an intermediate tray 103 dedicated to double-sided copying, and a manual-feed copy tray 105 are supported by the upper frame body A, and two paper feed cassettes 101 and 102 are supported by the lower frame body B, respectively. All of these cassettes except for the manual feed tray 105 are supported on rails fixed in the front and back direction of the frame body, and can be pulled out to the front side of the main body of the apparatus to set copy sheets and perform jam processing. There is. The copy sheets stacked in the sheet feed cassette 101 are fed to the image forming unit by the following operation. Note that FIG. 1 shows a schematic cross-sectional view of a sheet feeding device portion in the color image forming apparatus of the embodiment of the present invention.

First, the copy sheet ejected from the sheet feeding cassette 101 by the rotation of the pickup roller 51 is double-fed by the action of the retard roller 53 which is driven in the reverse rotation via the feed roller 52 and the torque limiter. Is prevented and only one sheet is separated and sent to the transport path. Here, the sheet feeding unit 91 is configured to have the rollers 51, 52, and 53. The copy paper sent out is detected by the paper detection sensor 64, then hits the conveyance roller pair 61 in the stopped state, and the skew of the leading end is corrected while forming a loop. When a certain period of time has passed since the paper detection sensor 64 detected, the control means actuates an electromagnetic clutch (not shown) provided in the drive unit of the conveyance roller pair 61, and the driving force is transmitted to copy the copy paper. , And is conveyed to the downstream conveying roller pair 62, 63. Similarly, the paper feeding from the paper feeding cassette 103 and the intermediate tray 103 is performed by the paper feeding means 9 including the pickup roller 54, the feed roller 55, and the retard roller 56.
2, pickup roller 57, feed roller 5
8, the sheet feeding means 93 including the retard roller 59 operates to feed the sheet.

FIG. 3 is a perspective view showing the outline of this embodiment. Each of the above-mentioned three paper feeding means 91, 92,
93 is divided into two sheet feeding units.
The sheet feeding means 91 and 92 are supported by the lower sheet feeding unit 41 including front and rear side plates 111 and 112, and the sheet feeding means 93 is supported by the refeeding unit 42 including front and rear side plates 113 and 114.

On the other hand, positioning pins 81 and 82 are provided on the upper front side plate A ₁ and the upper rear side plate A ₂ which constitute the main body. Further, positioning holes 111a, 112a and 113a, 114a are provided on the front and rear side plates of each paper feeding unit, and when the lower paper feeding unit 41 is assembled to the main body, the positioning pin 81 is used for positioning holes 111a. To
The positioning pins 82 are fitted in the positioning holes 112a, respectively. Further, the re-feeding unit 42 is installed in the main body 1
The positioning pin 81 is fitted in the positioning hole 113a and the positioning pin 82 is fitted in the positioning hole 114a when assembled to 00.

Here, the positioning pins 81 and 82 are obtained by caulking a sheet metal and screwing it to the front and rear side plates A ₁ and A ₂ of the main body. Alternatively, the front and rear side plates A ₁ and A ₂ of the main body may be directly caulked. A door guide 121 is pivotally supported on the lower sheet feeding unit 41 with a shaft 122 as a rotation center. The door guide 121 is a guide member that forms a paper conveyance path over both units when the lower sheet feeding unit 41 and the re-feeding unit 42 are attached to the main body, and can be freely opened and closed when jamming or the like. Is.

On the other hand, a drive motor 71A for driving the sheet feeding system is provided on the upper rear plate A _{2 of the} main body, and its drive output gear 71 projects inward from the upper rear plate A ₂ . The drive input to both sheet feeding units is first performed to the sheet refeeding unit 42. Here, FIG. 4 is a diagram showing the driving unit. The gear 72 is swingable around a shaft 76, and the spring 7
5 is urged in the direction of arrow 75a. When the re-feeding unit 42 is also assembled to the main body, the gear 72 meshes with the gear 71, and when the drive is applied, it becomes a bite-in, and the drive is transmitted to drive each part of the re-feeding unit 42.

Further, a gear 73 is connected to the lower sheet feeding unit 41.
The drive is transmitted by meshing with the gear 74. The gear 74 is swingable around a shaft 78 and is biased by a spring 77 in the direction of arrow 77a. Therefore, during the unit assembling work, the gear 74 avoids in the direction opposite to the arrow 77a, and when the drive is started after the assembling is completed, the drive is transmitted freely by the bite and drives the respective parts of the lower sheet feeding unit 41.

As described above, the positioning pins 81, are arranged on the upper frame A supporting the main device forming the printer unit, the photosensitive drum 1, the developing device 4, the transfer device 5, the fixing device 9, and the like.
82 is provided, and the lower sheet feeding unit 41 and the sheet re-feeding unit 42 are positioned with respect to the sheet feeding unit 82.
All of 1, 92 and 93 are positioned with high accuracy with respect to the printer unit. On the other hand, the feed rollers 51, 54, 57 are all the paper feed cassettes 101,
1012 and the intermediate tray 103 can be equalized. Therefore, in particular, the paper feed cassette 101,
102 is an upper frame A on which the paper feeding means 91, 92 are positioned
Is supported by a lower frame B different from
Along with the registration operations of Nos. 1 and 62, the positional deviation is corrected.

Further, since the gear 71, which is the drive input section, is also supported by the upper frame A, not only the positioning accuracy of the drive section is improved, but also the following effects are obtained.

That is, as shown in FIG. 5, it is possible to easily adopt a structure in which the paper feed cassette 106 is replaced in place of the intermediate tray 013. This includes the reverse paths 20 and 21 provided for double-sided copying from the above-described embodiment.
And the rail supporting the intermediate tray 103 may be replaced with a rail supporting the sheet feeding cassette 106.
Other parts regarding B may not be changed. However, similarly to the re-feeding unit 42, only the middle feeding unit 43 having the gear 72 that meshes with the gear 71 and the gear 73 that meshes with the gear 74 is configured. A sheet feeding unit is configured.

In this way, it is possible to easily combine the sheet feeding means to meet the needs of the user of the machine, and without compromising the unit positioning accuracy. <Other Embodiments> Next, other embodiments according to the present invention will be described.

In the present invention, since the main body frame constituting the image forming apparatus is composed of separate members above and below the dividing line D, the structure as shown in FIG. It is also easy to do. That is, instead of the lower frame body B of the above-mentioned embodiment, the lower frame body B'and the upper frame body A constitute the main body.

Here, the upper frame A is exactly the same as that of the above-described embodiment, and the lower frame B'does not support the sheet feeding cassette or the like, and the computer communication device 130 or the like can be installed. . Further, the paper feed cassette 106 and the middle paper feed unit 43 supported by the upper frame A are also the same as those in the above-described embodiment.

Therefore, in the present embodiment, the lower sheet feeding unit 41 is replaced with a door unit 44 which pivotally supports the door guide 121 in a similar manner, which is easily realized.

Further, as shown in FIG. 7, if a paper deck 107 capable of stacking a large amount of copy sheets is supported on the lower frame B ″, a paper feeding means may be used instead of the door unit 44. Owned Paper Deck Paper Feeding Unit 45
Can be easily configured. Here, the drive of the paper deck feeding unit 45 is input to the refeeding unit 42 from the driving source provided in the upper frame A via the gears 71 and 72, and the gear 73 is also driven, as in the above-described embodiment. , 7
It is sufficient to input via 4. Similarly, the door guide 121 is also rotatably supported by the paper feed unit 45 of the paper deck.

[0048]

As described above, according to the present invention,
The frame of the main body of the image forming apparatus is divided into upper and lower parts, the positioning means and the driving source are supported by the upper frame, and the door guide is arranged between the respective sheet feeding units, and each sheet feeding unit is driven by one driving source. By driving the, each paper feeding unit can be downsized, and the positioning accuracy of each paper feeding unit can be improved,
Further, it is possible to easily and inexpensively provide an image forming apparatus constituted by different sheet feeding means as a product group.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a sheet feeding device section of an image forming apparatus according to the present invention.

FIG. 2 is a vertical sectional side view of an image forming apparatus to which the present invention is also applied.

FIG. 3 is a perspective view of a state where the first and second sheet feeding units are mounted on the frame body.

FIG. 4 is a rear view showing a mounting state of the first and second sheet feeding units.

FIG. 5 is a vertical sectional side view of an image forming apparatus according to another embodiment of the present invention.

FIG. 6 is a vertical sectional side view of an image forming apparatus according to another embodiment 2 of the present invention.

FIG. 7 is a vertical sectional side view of an image forming apparatus according to another embodiment 3 of the present invention.

[Explanation of symbols]

 A Upper frame B, B ', B "Lower frame D Dividing line 1 Image forming unit 41 Lower sheet feeding unit 42 Refeeding unit 43 Medium sheet feeding unit 44 Door unit 71A Driving motor (driving source) 71 Driving gear ( Drive output part) 81,82 Positioning pin (positioning means) 91,92,93 Paper feeding means 100 Image forming apparatus main body 101,102 Paper feeding cassette 103 Intermediate tray 106 Paper feeding cassette 107 Paper deck 121 Door guide (guide member) 130 Computer communication equipment

Claims (5)

[Claims] 1. At least two paper feed cassettes arranged vertically in an image forming apparatus main body, and at least two paper feeds for feeding the sheets in each paper feed cassette to an image forming unit. And a lower frame body that is a member separate from the upper frame body, and the lower frame body is provided with at least one feeding unit. In an image forming apparatus in which a paper cassette is supported, the paper feeding unit includes a first paper feeding unit arranged upstream in a sheet conveying direction and a second paper feeding unit arranged downstream in a conveying direction.
And a sheet feeding unit, and each sheet feeding unit is positioned in the frame by a common positioning unit,
Further, the image forming apparatus is characterized in that the positioning means is provided on an upper frame member that supports an image forming unit among the frame members that form the main body. 2. A part of a sheet conveying path extending from the paper feeding unit to the image forming unit is configured to be openable and closable.
2. A guide member forming a sheet conveying path between the sheet feeding unit and the second sheet feeding unit is rotatably attached to the first sheet feeding unit. The image forming apparatus described. 3. The first sheet feeding unit and the second sheet feeding unit are driven by one driving source provided in the image forming apparatus main body, and the first and second sheet feeding units are driven from the driving source. 3. The image forming apparatus according to claim 1, wherein the drive input to the sheet feeding unit is input only to one of the sheet feeding units, and the drive is transmitted to the other sheet feeding unit between the sheet feeding units. apparatus. 4. The drive source and the drive output unit thereof are arranged in an upper frame member that supports the image forming unit in a frame member that constitutes the main body of the image forming apparatus. The image forming apparatus according to item 1. 5. An image forming apparatus, comprising: at least one sheet feeding cassette disposed in a main body; and at least one sheet feeding unit configured to feed a sheet in the sheet feeding cassette to the image forming unit, The frame forming the image forming apparatus includes an upper frame supporting the image forming unit and a lower frame separate from the upper frame, and the upper frame supports at least one sheet feeding cassette. In the image forming apparatus, the sheet feeding unit includes a sheet feeding unit supported by an upper frame member that supports the image forming unit in a frame member that configures the image forming apparatus main body, and a sheet conveying path across both the frame members. And a door unit rotatably rotatably supporting a guide member constituting the sheet feeding unit, and the sheet feeding unit and the door unit are positioned in the frame by a common positioning unit, and the positioning unit is The above An image forming apparatus characterized by being disposed on a frame supporting the image forming portion of the body.