JP2003152923A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device having a sliding guide mechanism of an original reading section with a simple constitution at low cost, without adding special parts and growing a product in size. SOLUTION: The image forming device comprises the original reading section 10 for reading an original image and an image processing section 30, which is arranged under the reading section, and that is an image forming section for performing image formation to a recording medium on the basis of image information read by the reading section. In the image forming device 100 where an opening for doing maintenance of the inside of the processing section can be opened and closed by sliding the reading section 10 to the processing section 30, a case of the reading section 10 is provided with projected parts 10a, 10b as guided parts and a case of the processing section 30 is provided with a guide hole 21a as a guide rail part for guiding these projected parts in a sliding direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus such as a copying machine, a facsimile, and a multi-functional machine having a printer function added thereto, and more particularly to an image forming apparatus having a slidable document reading unit. It is a thing.

[0002]

2. Description of the Related Art In a conventional image forming apparatus, a so-called process cartridge (hereinafter referred to as a process cartridge) in which a photosensitive drum, a developing device, a charging device, a cleaning device and the like are integrally housed is replaced. Maintenance work such as taking out the process cartridge from the image forming apparatus and performing post-processing for sheet jamming in the image forming apparatus, for example, in the case of a small platen moving type copying machine, a contact glass serving as a document mounting table is used. After the horizontal movement of the process cartridge, the process cartridge is generally opened through the opening of the lid for opening the process cartridge.

On the other hand, a fixed platen type, a document illumination lamp,
In a copying machine having a configuration in which an optical system having a mirror or the like is moved to read an original (so-called optical system moving type), a part of the exterior of the copying machine main body (usually the front side) other than the contact glass which is the original placing table After that, maintenance such as replacement of consumables such as process cartridges and post-processing of sheet jams is performed.

Here, in the case where the process cartridge is pulled out upwards and taken out, when it is applied to the above-mentioned fixed platen type copying machine and facsimile, the process cartridge is taken out when the process cartridge is taken out. Since the cartridge and the document reading unit interfere with each other, there are the following problems.

(1) When the height of the original reading portion is increased and a space is provided to allow a margin for taking out the process cartridge, the height of the original reading portion is increased,
This leads to deterioration of the operability of the device and increase in size.

(2) In the method of taking out the process cartridge after pulling out the image forming section including the process cartridge to the outside of the apparatus and the method of taking out the process cartridge by rotating and opening the entire document reading section, the apparatus main body structure and the hinge are strong. Since parts and oil dampers are required, the manufacturing cost of the device increases.

(3) When the method of changing the take-out direction of the process cartridge from the image forming section is adopted,
The diversion effect of the process cartridge is lost, cost reduction due to the mass production effect becomes difficult, and the number of development man-hours increases.

In order to solve such a problem, the original reading section 320 of the image forming apparatus (here, a so-called digital copying machine) 300 as shown in FIG.
0, the image forming section 370, and the fixing section 380, and the like, the image processing section 350 is provided with a slide guide mechanism that slides in the direction of arrow t in FIG. There is also provided an image forming apparatus that exposes 375 and takes out the process cartridge. In this conventional example, the image forming apparatus 300
15 rotates the lever 323 provided on the document reading unit 320 side in the v direction in FIG.
The locking portion 353 provided on the 0 side and the hook portion 324 integrally formed with the lever 323 are unlocked, and the document reading portion 320 is pulled in the direction t in FIG. The horizontal movement of 320 is performed. In addition,
In the state of FIG. 15, the document reading unit 320 is biased and positioned in the t direction in the drawing by a coil spring (not shown).

FIG. 16 shows a state in which the document reading section 320 is horizontally moved to the open position. As shown in the figure, the process cartridge 371 can be taken out from the image processing unit 350 by pulling it out from the opening 375 in the arrow u direction. Further, post-processing when the sheet is jammed can also be performed from the opening 375.

[0010]

However, in the slide guide mechanism of the document reading section 320 in the above-mentioned conventional example, the slide rail 322 coupled to the optical frame 321 to configure the slide guide mechanism,
Slide roller 322a provided on the image processing unit 350 side
A slide shaft 322b and a fastening means for these components are required.

Therefore, by disposing such components in the image forming apparatus, the size of the apparatus is increased. Further, the cost of these components and the manufacturing cost for assembling lead to an increase in the product price of the image forming apparatus.

The present invention has been made in view of the above-mentioned problems, and image formation having a slide guide mechanism of a document reading section without adding special parts or increasing the size of a product. The purpose is to provide the device at low cost.

[0013]

In order to achieve the above object, in the first invention of the present application, an original reading portion for reading an image of an original and a lower portion of the original reading portion are arranged.
An image forming unit that forms an image on a recording medium based on image information read by the document reading unit, and slides the document reading unit with respect to the image forming unit to maintain the inside of the image forming unit. In an image forming apparatus capable of opening and closing an opening for storing a guide rail in one case of the document reading section and the image forming section and guiding the guided section in a sliding direction in the other case. It is characterized by the provision of.

By constructing such an image forming apparatus, it is not necessary to add a component such as a slide roller or a slide shaft or a complicated structure as in the prior art, that is, to add a special component or to increase the size of a product. It is possible to provide an image forming apparatus having a slide guide mechanism of a document reading unit having a simple structure at low cost without changing.

Further, in the second invention of the present application, the guide rail portion is arranged so as to extend in the sliding direction at a substantially central position in a direction orthogonal to the sliding direction in the other case. There is.

In the conventional slide guide mechanism, for example, slide rollers and slide shafts are arranged on both sides in the moving direction. However, such a guide rail portion and separation prevention rail portion are provided on the surface of the case. If it is arranged at a substantially central position, it is not necessary to arrange it on both sides of the case unlike the conventional slide guide mechanism.

Further, in the third invention of the present application, at least one is arranged in the one case so as to be guided together with the guided portion by the guide rail portion and prevents rotation of the document reading portion with respect to the image forming portion. It is characterized by having a rotation preventing protrusion.

With such a configuration, it is possible to prevent the document reading unit from being slanted when the document reading unit slides with respect to the image forming unit, and preventing the document reading unit from rotating with respect to the image forming unit when stationary. You can

Further, in the fourth invention of the present application, the guided portion integrally has a separation preventing portion, and the separation preventing portion engages with the other case to cause the original reading portion and the image forming portion. It is characterized by preventing the vertical separation of the.

By adopting such a structure, it is possible to add a special component or to increase the size of the apparatus,
It is possible to provide at low cost an image forming apparatus having a slide guide mechanism for the document reading unit that can prevent the document reading unit and the image forming unit from being separated from each other in the vertical direction.

Further, in the fifth invention of the present application, separation preventing portions are provided at both side ends of one of the document reading portion and the image forming portion in a direction orthogonal to the sliding direction, and the separation is provided in the other case. It is characterized in that a separation preventing rail portion is provided which is engaged with the prevention portion and prevents separation of the document reading portion and the image forming portion in the vertical direction.

With such a structure, similarly to the fourth aspect of the present invention, the original reading unit and the image forming unit can be vertically moved without adding any special parts or increasing the size of the apparatus. An image forming apparatus having a slide guide mechanism of a document reading unit that can prevent separation can be provided at low cost.

Further, since the separation preventing portions are arranged at both ends of the case (that is, the separation preventing portions are not arranged in the vertical direction), the size of the document reading portion and the image forming portion in the vertical direction is reduced. As a result, the height of the entire device can be reduced.

In the sixth invention of the present application, the document reading section has a document mounting table on which a document is mounted, and a driving unit for driving a reading optical system for reading an image of the document on the document mounting table. However, the separation prevention unit is arranged closer to the closing direction than the drive unit in the document reading unit.

With such a structure, even when the driving means, which is generally heavy, is built in the original reading portion, it is effective to prevent the original reading portion from floating. Particularly, when the driving unit is provided near the end of the document reading unit in the opening direction, it is possible to prevent an adverse effect such as floating of the end of the document reading unit in the closing direction due to an imbalance due to the weight of the driving unit. You can

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows an image forming apparatus according to a first embodiment of the present invention. The image forming apparatus according to the present embodiment includes a document reading unit, and a copying machine (so-called digital copying machine) is shown as an example here.

The document reading unit according to the present embodiment can be incorporated not only in a copying machine, but also in a facsimile machine, a multi-function machine having a printer function added thereto, or the like.

The copying machine 100 includes a document reading section 10 and
An image processing unit 30 as an image forming unit is disposed below the document reading unit 10. The image processing unit 30 includes a cassette 60 in which a sheet S as a recording medium of a predetermined amount is stacked and stored below the image processing unit 30. In the vicinity of the cassette 60, the sheet supply unit 5 that supplies the sheet S
A sheet supply roller 51 forming a part of 0 is provided. The cassette 60 here is a so-called claw separation type cassette, and the operation of separating the sheet S from the bundle of sheets S one by one is performed by a separation claw 61 provided in the cassette 60. The sheet S fed by the sheet feeding roller 51 is conveyed by the conveying roller pair 52 and comes into contact with the stopped registration roller pair 53. By abutting against the registration roller pair 53 in this way,
The skewed state of the sheet S is corrected.

The sheet S can also be fed from the manual feed section 90. The manual feeding unit 90 is the image processing unit 30.
The stacking unit 91, which is arranged so as to be openable and closable with respect to the side surface of the sheet S, is used by rotating it in the clockwise direction on the plane of FIG. The sheet S stacked on the stacking unit 91 is fed by the feeding roller 92 toward the registration roller pair 53.

After passing through the registration roller pair 53, the sheet S is sent to an image forming means 70 including a process cartridge 71, a transfer charger 73 and the like. In the process cartridge 71, a charging device, a toner, a developing device, and a cleaning device (not shown) and the photosensitive drum 72 are integrally formed into a cartridge, and the cartridge is used.
It is configured to be attachable to and detachable from 0. The laser scanner unit 80 irradiates the photosensitive drum 72 in the process cartridge 71 with a light beam to form an electrostatic latent image based on the image signal obtained by the document reading unit 10. This electrostatic latent image is developed by the developing device in the process cartridge 71 using toner to be visualized. On the sheet S sent to the image forming means 70, the toner image on the photosensitive drum 72 is transferred by the transfer charger 73 to form an image. After this, the sheet S
Is transported by the transport unit 74 to the fixing device (that is, a pair of fixing rollers) 7
Then, a fixing process for fixing the transferred toner image on the sheet surface is performed. Sheet S after fixing process
Is discharged to the outside of the machine by a pair of discharge rollers 76.

In FIG. 1, the document reading unit 10 is in the closed position as shown in the drawing, and the copying machine 100 is in a state in which sheets can be conveyed for copying a document. Document reader 1
0 is equipped with a contact image sensor 11 having a selfoc lens with a short focal length. The contact image sensor 11 is urged from below by a coil spring 12 via an abutting member 13 against a document table glass 14 on which a document is placed. The contact image sensor 11 is scanned in the direction a in the drawing while being guided by the shaft 15 for reading an original by the timing belt 16 and the drive system 17. Reference numeral 18 is an original pressing plate for holding the original on the original table glass 14.

As shown in FIG. 1, the locking portion 19 as an engaged portion provided at the end of the document reading portion 10 is
It is in a state of being engaged with the hook portion 20 as an engaging portion provided on the image processing unit 30 side. At this time, the document reading unit 10 is biased in the F direction (that is, the opening direction of the document reading unit 10) by a coil spring (not shown) arranged between the image processing unit 30 and the document reading unit 10. There is. With such a configuration, the document reading unit 10 is positioned in the horizontal direction in the drawing.

On the other hand, when the process cartridge 71 is replaced when it is worn out or the post-processing is performed when the sheet S is jammed, the hook 20 is rotated in the direction b in the figure (that is, until the state shown by the broken line). Let This allows the hook 20
The document reading unit 10 which has been unlocked by, is biased by a coil spring (not shown), starts horizontal movement (slide) in the F direction in the drawing, and is pushed in by the user in the F direction in the drawing. Guided to the open position.

FIG. 2 shows a state in which the document reading unit 10 is horizontally moved to the maximum in the F direction in the figure (that is, the document reading unit 10 is in the open position). In this state, the opening 22 is provided on the upper surface on the right side of the image processing unit 30 in FIG.
Is exposed. By exposing the opening 22 in this manner, during maintenance such as insertion / removal of the process cartridge 71 and post-processing for sheet jamming of the sheet S, the inside of the apparatus through the opening 22 by a user or a service person. Access to.

FIG. 3 is a perspective view of the upper surface cover 21 arranged so as to cover a part of the upper surface of the image processing section 30, as viewed from above. The upper surface cover 21 is formed of a resin material such as a PC-ABS material. FIG. 4 is a perspective view of the bottom surface of the document reading unit 10 as seen from below. The frame body 10d as a case of the document reading unit 10 also includes the top cover 2
Like No. 1, it is made of a resin material having good moldability such as an ABS material. As shown in FIG. 3, a guide hole 21a as a guide rail portion extending in the F direction in the drawing is provided at a substantially central portion of the top cover 21. Further, the side of the guide hole 21a opposite to the direction indicated by the arrow F in the figure (close direction side)
An opening 21b formed of a substantially rectangular through hole extending in a direction (Y direction) substantially orthogonal to the direction in which the guide hole 21a extends is arranged at the end of the guide hole 21a. A V-shaped through hole is formed.
Through the guide hole 21a, the bottom surface 1 of the document reading unit 10 is
The protrusion 10a having a function as a guided portion and the protrusion 10b as a rotation preventing protrusion, which are provided to extend vertically from 0c, are guided. When the document reading unit 10 is horizontally moved, the protrusions 10a and 1
0b will move along the guide hole 21a.

Specifically, the protrusion 10a is a cylindrical portion 10a.
1 and a restricting portion 10a2 which is formed below the columnar portion 10a1 and which is larger than the dimension of the columnar portion 10a1 in the diameter direction and serves as a separation preventing portion. The planar shape of the limiting portion 10a2 is substantially rectangular. The width l of the limiting portion 10a2 is larger than the width m of the guide hole 21a and smaller than the width n of the opening 21b.

On the other hand, the protruding portion 10b has a columnar shape having substantially the same diameter as the columnar portion 10a1.

The horizontal movement amount of the document reading section 10 is shown in FIG.
As shown in the figure, the position h of the protrusion 10b in the closed position
To the position i of the protrusion 10b in the open position.

As shown in FIGS. 1 and 2, the document reading unit 10 is configured to be placed on the upper surface cover 21, and at this time, the document reading unit 10 is inserted by inserting the limiting unit 10a2 into the opening 21b. Can be incorporated into the top cover 21. The limiting portion 10a2 is a top cover 21.
This prevents the document reading unit 10 from coming off in the vertical direction after being incorporated in the document reading unit 10. At this time, the edge portion on the bottom surface side of the guide hole 21a plays a role of blocking the limiting portion 10a2 and preventing vertical separation between the document reading portion 10 and the image processing portion 30. Projections 21c are integrally provided at four locations on the top cover 21. The convex portion 21c is configured to receive the bottom surface 10c of the document reading portion 10, and the bottom surface 10c and the convex portion 21c when the document reading portion 10 slides.
Will rub against each other.

A narrowed portion 21a-1 is provided in the guide hole 21a, and the width m'of this narrowed portion 21a-1 is narrower than the width m of the portion other than the narrowed portion 21a-1 (m. '<M). When the document reading unit 10 is in the closed position (image forming is possible by the image forming apparatus 100),
The projecting portion 10a is configured to be located on the narrowed portion 21a-1, and at this time, the columnar portion 10a1 and the narrowed portion 21a-.
It is set so as to have a fitting relationship with 1 (in the present embodiment, the former is φ8H10 and the latter is φ8g9).
Therefore, the document reading unit 10 is positioned in the Y direction in FIGS. 3 and 4 at the closed position.

As shown in FIG. 2, in the image forming apparatus 100, the contact image sensor 11 and the drive system 17 are provided.
The components such as are arranged on the left side in the document reading section 10, and the weight balance of the document reading section 10 in the left-right direction on the paper surface of FIG. 2 is biased to the left side. Therefore, as shown in FIG. 2, when the document reading unit 10 is located at the open position, the right portion of the document reading unit 10 tries to float up in the direction k in FIG. 2 due to the imbalance of the weight. In order to suppress the influence of such weight imbalance as much as possible, the disposition position of the protrusion 10a on the bottom surface 10c is defined by the center position of the document reading unit 10 (position C in FIGS. 2 and 4) as a boundary. It is preferable to dispose it in a region on the right side in the drawing, and it can be said that it is desirable to dispose it in a position as far as possible from the central position (position C in FIGS. 2 and 4) in consideration of the size of the opening 22. . Column part 10
Regarding the length r of a1, the guide hole height P of the guide hole 21a, the height q of the convex portion 21c, and the guide hole height P when sliding
It will be decided in consideration of clearance with. Regarding the length of the protrusion 10b, the guide hole height P and the protrusion 21
It may be about the same as the sum of the height c and the height q.

5 to 7 show a state in which the document reading section 10 is moved horizontally. FIG. 5 shows a state where the document reading unit 10 is in the open position (state in FIG. 2).
An opening 22 is exposed at the lower right of the document reading unit 10. Then, the user manually pulls the document reading unit 10 of the image forming apparatus 100 in the F ′ direction in the drawing to close the document reading unit 10 (the state shown in FIG. 1).
Lead to.

FIG. 6 shows a state in which the document reading unit 10 is in the middle of a sliding operation.

FIG. 7 shows a state (state of FIG. 1) in which the document reading portion 10 is in the closed position. In this closed position,
The protrusion 10a is located at a position h'of a guide hole height P '(P'> P) higher than the guide hole height P. The relationship between the guide hole height P ′ at this position h ′ and the length r of the columnar portion 10a1 is that the limiting portion 10a2 and the bottom surface 10 of the document reading portion 10 have the following relationship.
The upper surface cover 21 is set to have a fitting relationship with the gap between the upper surface cover 21 and c. In this way, the document reading unit 10 is vertically positioned at the closed position. As described above, the positioning in the F (F ') direction is performed by the engagement between the hook 20 and the locking portion 19 and the biasing force in the F direction by the coil spring (not shown). The hook 20 is urged by a tension spring 23 in the b'direction in the figure.

The copying machine 100 of this embodiment is a so-called digital copying machine, and the image processing section 3 of the document reading section 10 is used.
The disposition position with respect to 0 is arbitrary, but it is required to be securely fixed in order to prevent image defects. With the configuration as described above, the document reading unit 10
Direction (that is, the above-described sliding directions F and F ′, Y direction, and up-down direction), and the document reading unit 10 is used for inserting / removing the process cartridge 71 and for post-processing when the sheet S is jammed. The slide guide mechanism can be provided with an inexpensive structure without increasing the size of the device.

(Second Embodiment) FIGS. 8 to 11 show an image forming apparatus according to a second embodiment of the present invention.

FIG. 8 is an overall sectional view showing the image forming apparatus according to the second embodiment. In this embodiment, the image processing unit 250 as the image forming unit of the copying machine 200 and the image processing unit 30 of the first embodiment are different only in the top cover 251. Further, the document reading unit 230 is also the same as the internal configuration of the document reading unit 10 in the first embodiment except the optical frame body 231, and the description of these same portions will be omitted.

FIG. 9 shows an upper surface cover 251 as a case arranged so as to cover a part of the upper surface of the image processing section 250.
It is the perspective view which drew out. FIG. 10 is a perspective view of the bottom of the document reading unit 230 as viewed from below.

As shown in FIG. 9, the upper surface cover 251 is provided with a guide hole 251a as a guide rail portion. The document reading portion 230 is provided in the guide hole 251a.
2 as a guided portion provided on the frame body 231 of
33a and 23 serving as a rotation preventing protrusion
3b engages and moves while being guided by the guide hole when the document reading section 230 slides. As shown in FIG. 9, the amount of slide of the document reading unit 230 is from the position hl of the protrusion 233b at the closed position (the position where the image forming apparatus 200 is operable) to the protrusion 2 at the open position.
It is the operation stroke jl up to the position il of 33b.

A narrowing portion 251a-1 is provided near the end of the guide hole 251a in the closing direction. The width ml 'of this narrowing portion 251a-1 is the width ml of the portion other than the narrowing portion 251a-1. It is narrower than that (ml '<ml).
When the document reading unit 230 is in the closed position, the protrusion 2
33a is configured to be located in the narrowed portion 251a-1, and at this time, the protrusion portion 233 formed in a cylindrical shape.
It is set so that a (the same shape of 233b) and the width ml 'have a fitting relationship. In this way, the document reading portion 230 at the closed position is positioned in the Yl direction in FIGS. The protrusions 233a and 23
Unlike the first embodiment, 3b does not participate in the vertical positioning, so that the arrangement position on the bottom surface 234 may be arbitrarily determined from the relationship between the opening 22 and the operation stroke jl.

The upper cover 251 has four convex portions 251.
c is integrally molded and is configured to receive the bottom surface 234 of the document reading unit 230, and the bottom surface 234 and the convex portion 251c rub against each other when the document reading unit 230 moves horizontally. In addition, the protrusions 233a and 2
The length rl of 33b may be about the same as the sum of the guide hole height Pl of the guide hole 251a and the height ql of the convex portion 251c.

As shown in FIG. 9, rails 251d as separation preventing rails are integrally provided on the upper surface cover 251 on both front and back sides of the paper so as to extend in the sliding direction. . This configuration is advantageous in terms of part manufacturing cost. Further, the rail portion and the upper surface cover may be separately provided, and may be fastened by a fastening member or the like. On the rail portion 251d, columnar protrusions 232a and 232b are formed on the front and back sides (the side facing the rail portion 251d) of the optical frame 231 as columnar separation preventing portions (see FIG. 10). And the document reading section 23
When the slide operation is 0, the rail portion 251d moves while being guided.

In the image forming apparatus 200 of the present embodiment, as shown in FIG. 8, the drive system (not shown) (similar to the first embodiment) provided on the left side in the figure in the document reading section 230 is arranged. Since the automatic document feeder 210 is provided on the right side opposite to the installed position, the protrusions 232a and 232b are located at the central position of the document reading unit 230 (that is, the C'position in FIGS. 8 and 10). Even if it is provided on the left side of the figure with the boundary as the boundary, the right side portion of the document reading portion 230 does not float up. Note that the protrusions 232a and 2
The position of 32b is not limited to the position of the present embodiment, and may be provided at any position according to the arrangement position of the automatic document feeder, the operation unit for performing various operations of the image forming apparatus, and the like. You can

FIG. 11A shows the rail portion 251d in FIG.
It is sectional drawing seen from the middle arrow S direction. FIG. 11B shows
It is sectional drawing seen from the arrow Z direction in FIG. The two-dot chain line in FIG. 11 indicates the protrusion 232a. In FIG. 11, the position h2 showing the protrusion 232a is the closed position of the document reading unit 230 (the position in FIG. 8). At the position h2, the rail width w is equal to the cylindrical protrusion 23 having a diameter r2.
It has a fitting relationship with 2a. The rail width w ′ in the portion other than the vicinity of the position h2 is formed to be larger than the diameter r2.

With such a configuration, the document reading section 230 is positioned in the vertical direction at the closed position.
The shape of the protrusion 232a is cylindrical in this embodiment, but the shape is not limited to this.
Needless to say, the same effect can be obtained as long as the shape is such that the rail width w and the rail width w can be fitted with each other.

Further, the positioning in the sliding direction is the same as in the first embodiment, and the positioning is performed by the engagement of the hook portion 20 and the engaging portion 235. At this time, the document reading unit 230 is also biased in the opening direction by a coil spring (not shown).

In this embodiment, since the length of the protrusion 233a as the guided portion formed on the bottom surface 234 can be made shorter than that of the protrusion 10a in the first embodiment, the height of the image forming apparatus as a whole is increased. It can be suppressed, and it can meet the demand for office equipment that is required to be downsized. In particular, the automatic document feeder 210 as shown in FIG.
It becomes even more advantageous when equipping such equipment.

(Third Embodiment) FIGS. 12 to 14 show an image forming apparatus according to a third embodiment of the present invention.

This embodiment is a modification of the top cover in the above-mentioned first and second embodiments.

FIG. 12 is a perspective view of the top cover 351 in this embodiment as seen from above. 13 is the same as FIG.
It is a u-u section inside. As shown in FIG. 12, the guide hole 351a of the top cover 351 does not include the narrowed portion 21a-1 as seen in the guide hole 21a of the top cover 21 in the first embodiment. Further, as shown in FIG. 13, the guide hole height P2 does not have the guide hole height difference (the dimensional difference between P and P ′) as seen in the top cover 21 in the first embodiment.

That is, the original reading portion of the image forming apparatus according to the present embodiment has the same protrusion 10 as that of the first embodiment.
The guide hole 351a has a fitting relationship with the projections 10a and 10b in the entire sliding direction. Here, the width m2 is the same width as m'shown in the first embodiment, and the guide hole height P2 is the same height as the guide hole height P'shown in the first embodiment. In this embodiment, the upper surface cover 35
1 and / or the protrusions 10a and 10b can be applied when molded with a resin material having improved slidability, and can be selected depending on the price of the resin material and the like. Further, also in the top cover 251 of the above-described second embodiment, it is possible to adopt the guide hole 351a of this embodiment instead of the guide hole 251a.

FIG. 14 shows a guide hole 351 in this embodiment in the top cover 251 in the above-mentioned second embodiment.
The rail portion 4 of the upper surface cover 451 when a is applied.
It is a figure explaining 51d. As shown in the figure,
Protrusions 232a and 232b similar to those in the second embodiment
Have a fitting relationship with the entire area of the rail portion 451d. That is, the rail width w2 has the same dimension as the rail width w described above.

In each of the above-described embodiments, the protrusion as the guided portion is provided in the case of the document reading portion, and the guide hole as the guide rail portion is formed in the case of the image forming portion. However, the configuration is not limited to this, and the guide hole may be formed in the case of the document reading unit and the protrusion may be provided in the case of the image forming unit.

Further, in each of the above embodiments, the separation prevention rail portion is provided in the case of the image forming portion and the separation prevention portion is provided in the case of the document reading portion, but the invention is not limited to this, and the separation prevention portion is not limited thereto. The prevention unit may be provided in the case of the image forming unit, and the separation preventing rail unit may be provided in the case of the document reading unit.

In each of the above embodiments, the locking portion for holding the original reading portion in the closed position is provided at the end portion of the original reading portion, and the hook portion is provided on the image processing portion side, but the present invention is not limited to this. Instead, the hook portion may be provided at the end of the document reading portion and the locking portion may be provided at the image processing portion side. At this time, one of the document reading section and the image processing section and the hook section, and the other and the locking section may be integrally molded of a resin material.

Of course, one of the document reading section and the image processing section and the guided section, and the other case and the guide rail section may be integrally formed of a resin material.

In each of the above-mentioned embodiments, it is possible to use ordinary copy paper, printer paper, OHP sheets, etc. as sheets.

[0068]

As described above, according to the inventions of the present application, a document reading unit for reading an image of a document and a recording medium arranged below the document reading unit and based on image information read by the document reading unit. And an image forming unit that forms an image on the image forming unit, and an opening for opening and closing an opening for maintaining the inside of the image forming unit by sliding the document reading unit with respect to the image forming unit. By providing the guided part in one case of the forming part and the guide rail part that guides the guided part in the sliding direction in the other case, it is possible to add components such as a slide roller and a slide shaft as in the conventional case. No need for complicated structure, that is, without adding special parts or increasing the size of the product, the slicing of the original scanning unit has a simple structure. It is possible to provide an image forming apparatus having a guide mechanism at a low cost.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a general configuration of an image forming apparatus according to a first embodiment of the present invention (document reading unit closed position).

FIG. 2 is a vertical cross-sectional side view (document reading unit open position) showing the overall configuration of the image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a top cover of the image forming apparatus according to the first embodiment of the present invention.

FIG. 4 is a perspective view of the bottom surface of the document reading unit of the image forming apparatus according to the first embodiment of the present invention as seen from below.

FIG. 5 is an enlarged view of the document reading unit of the image forming apparatus according to the first embodiment of the present invention in an open position.

FIG. 6 is an enlarged view of the document reading unit according to the first embodiment of the present invention when the document reading unit is horizontally moved.

FIG. 7 is an enlarged view of the document reading unit according to the first embodiment of the present invention in a closed position.

FIG. 8 is a vertical cross-sectional side view (original reading unit closed position) showing an overall configuration of an image forming apparatus according to a second embodiment of the present invention.

FIG. 9 is a perspective view of a top cover according to a second embodiment of the present invention.

FIG. 10 is a perspective view of the bottom surface of the document reading unit according to the second embodiment of the present invention as seen from below.

FIG. 11 is a supplementary explanatory diagram of the top cover of the image forming apparatus according to the second embodiment of the present invention.

FIG. 12 is a perspective view of a top cover of an image forming apparatus according to a third embodiment of the present invention.

FIG. 13 is a sectional view of a top cover of an image forming apparatus according to a third embodiment of the present invention.

FIG. 14 is an explanatory diagram of a top cover of an image forming apparatus according to an application of the second and third embodiments of the invention.

FIG. 15 is a vertical cross-sectional side view (original reading unit closed position) showing the overall configuration of a conventional image forming apparatus.

FIG. 16 is a vertical cross-sectional side view showing an overall configuration of an image forming apparatus of a conventional example (document reading unit open position).

[Explanation of symbols]

10 Document reading section 10a protrusion 10a1 cylindrical part 10a2 restriction section 10b protrusion 10c bottom 10d frame 11 Contact image sensor 12 coil spring 13 Abutting member 14 Platen glass 15 axes 16 belts 17 Drive system 18 Original plate 19 Locking part 20 hooks 21 Top cover 21a Guide hole 21b opening 21c convex part 22 opening 23 Extension spring 30 Image processing unit 60 cassettes 71 Process cartridge 100 image forming apparatus 200 image forming apparatus 230 Document reader 231 Optical frame 232a protrusion 232b protrusion 233a protrusion 233b protrusion 234 bottom 235 Engagement part 250 image processor 251 Top cover 251a guide hole 251c convex part 251d rail part 320 Document reading section 322a slide roller 322b slide shaft 323 lever 350 image processing unit 351 Top cover 351a Guide hole 353 locking part 451 Top cover 451d rail part l Width of the limiting portion 10a2 Width of guide hole 21a n width of the opening 21b P Guide hole height of guide hole 21a q Height of the convex portion 21c w Rail width S sheet

Claims (19)

[Claims] 1. An original reading unit for reading an image of an original, and an image forming unit arranged below the original reading unit for forming an image on a recording medium based on image information read by the original reading unit. An image forming apparatus having an opening for opening and closing the document reading unit with respect to the image forming unit to maintain the inside of the image forming unit, wherein one of the document reading unit and the image forming unit An image forming apparatus, wherein the case is provided with a guided portion, and the other case is provided with a guide rail portion for guiding the guided portion in a sliding direction. 2. The guide rail portion is arranged so as to extend in the sliding direction at a substantially central position in a direction orthogonal to the sliding direction in the other case. Image forming apparatus. 3. At least one anti-rotation projection part, which is arranged in the one case so as to be guided together with the guided part by the guide rail part and prevents rotation of the document reading part with respect to the image forming part. The image forming apparatus according to claim 1, wherein: 4. The guided portion integrally has a separation prevention portion, and the separation prevention portion engages with the other case to separate the original reading portion and the image forming portion in the vertical direction. The image forming apparatus according to claim 1, which blocks the image forming apparatus. 5. A separation prevention part is provided at both ends of one of the document reading part and the image forming part in a direction orthogonal to the sliding direction, and the other case is engaged with the separation prevention part. 2. A separation preventing rail portion is provided for preventing separation of the document reading portion and the image forming portion in a vertical direction.
The image forming apparatus according to item 1. 6. The original document reading section includes an original document table on which an original document is placed, and driving means for driving a reading optical system for reading an image of the original document on the original document table, and the separation prevention unit. 6. The image forming apparatus according to claim 4, wherein the unit is arranged on the side closer to the closing direction than the driving unit in the document reading unit. 7. The drive means is arranged on the opening direction side of the central position in the slide direction of the document reading section, and the separation prevention section is arranged on the closing direction side of the central position. The image forming apparatus according to claim 6, wherein 8. The guide rail portion has a shape that increases the slide resistance with respect to the guided portion when the document reading portion is in a region near the closed position as compared with when it is in another region. The image forming apparatus according to claim 1, wherein: 9. The image forming apparatus according to claim 1, wherein the guide rail portion is engaged with the guided portion so as to exert a slide resistance in the entire sliding direction. 10. The other case has a shape that increases the slide resistance with respect to the separation prevention unit when the document reading unit is in a region near the closed position as compared with when the document reading unit is in another region. The image forming apparatus according to claim 4. 11. The image forming apparatus according to claim 4, wherein the other case is engaged with the separation preventing portion so as to apply a slide resistance in the entire sliding direction. 12. The other case has a shape such that a gap is formed between the separation prevention section and the other case when the document reading section is in a region other than the vicinity of the closed position. The image forming apparatus according to claim 4, characterized in that: 13. The other case is separated from the other case in a direction in which the one case is in close contact with the other case when the document reading portion is in a region near the closed position, as compared with when the document reading part is in another region. The image forming apparatus according to claim 4, wherein the image forming apparatus has a shape that guides the prevention portion. 14. The image forming apparatus according to claim 1, wherein the guided portion abuts on an end portion of the guide rail portion in the opening direction when the document reading portion is at the open position. 15. The lock mechanism according to claim 1, further comprising a lock mechanism that locks and holds the document reading unit so as to prevent the document reading unit from sliding when the document reading unit is in a closed position. The image forming apparatus described. 16. The lock mechanism includes an engaging portion and an engaged portion that engages with the engaging portion, the case of the document reading portion and the engaged portion, and the image forming portion. The image forming apparatus according to claim 15, wherein the engaging portion and the engaging portion are integrally formed of a resin material. 17. The image forming apparatus according to claim 1, wherein the one case and the guided portion are integrally formed of a resin material. 18. The image forming apparatus according to claim 1, wherein the other case and the guide rail portion are integrally formed of a resin material. 19. The image forming apparatus according to claim 1, wherein the image forming unit is of an electrophotographic type.