JPS63244059A - Image forming device - Google Patents

Abstract

PURPOSE:To permit approach from the same direction to dispose of a jam and to maintain a device and to permit reduction of the size of the device by constituting an image forming means in such a manner that said means can be detached to the outside of the device in the detaching direction of a conveying means. CONSTITUTION:A coupler gear 58 part is disposed to a device base 10 side of the body part and a driving gear 59 for paper feeding is pivotally supported by a feed roller shaft and is disposed in an external cover part K having paper feeding, conveying and fixing parts. Coupling and releasing of the drive are executed by attaching and detaching the cover part K to and from the device body. More specifically, the conveying means for guiding a transfer material to the image forming means is formed detachably from the image forming means and the image forming means is so constituted that part or the whole thereof can be detached from the inside of the device body in the detaching direction thereof. The size of the aperture for disposing of jam is thereby increased and the approach to the opening operation for disposing of jam and the image forming means to make the maintenance and exchange work thereof is permitted. The smaller-sized image forming device having good operability is thereby obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the configuration of an image forming apparatus such as a copying machine or a printer that forms an image on a transfer material.

[Conventional technology]

Conventionally, when copiers, LBPs, etc. use electrophotography for image formation, it is necessary to replenish developer or replace the photosensitive drum, which has a long service life, as part of the image forming means or as in personal copying machines. The entire main part of the image forming means is taken out of the main body of the apparatus as a cartridge for maintenance or replacement. Also, on the other hand,
A transfer material transport path is configured to transport the transfer material into the device, guide it to the image forming means, form an image, and then discharge it outside the device. When the transfer material becomes jammed, the conveyance path is opened to remove the transfer material, making it easier for the user to remove it. FIG. 9(a) shows an example in which the front cover is opened and a part of the conveyance path is separated from the image forming means, such as a photosensitive drum, and the operator puts his hand into the open space and takes out the jammed paper. . In addition, in FIG. 10(a), the conveyance path is fixed to the lower part of the main body of the apparatus, and the image forming means including the photosensitive drum etc. is removed to the upper part to open the conveyance path so that the operator can easily take out the jammed paper. It is composed of It has a clamshell structure and is called an alligator opening/closing type.

The example in FIG. 9(b) is a configuration that is often used when equipment such as medium- to high-speed machines that print 15 to 20 sheets per minute or more has become large. After opening the cover, the image forming means, such as a photosensitive drum, a developing device, and in the case of this conventional example, the developing device is pulled out toward the front cover side.

The example shown in FIG. 10(b) is a configuration used in a small device of a low-speed machine capable of printing 10 sheets per minute or less. Then, the cartridge of the image forming means including the photosensitive drum, cleaner, charger, developer, and charger is pulled out to the front side of the apparatus and maintenance or replacement is performed.

[Problem that the invention is trying to solve] However,
In the conventional example and the first example, the conveyance path is opened inside the device, so the operator has to insert his hand into the open hole on the front plate side and remove the jammed paper. It had some serious drawbacks.

Since the image forming means is also pulled out through the open hole in the front plate, a large hole is formed in the front plate, which is disadvantageous in terms of strength and vibration.

In addition, in the second example, since the upper unit of the image forming means such as the photosensitive drum is detached upward, the upper unit has a transport path and is larger than the lower unit which has heavy objects such as radio waves on the bottom plate. It is weak against vibrations (and the weight of the upper unit cannot be increased too much, which causes image blurring and other image defects due to vibration of the image forming means. Also, the image forming means is constructed of precision and high-precision parts. As a result, the impact caused by opening and closing the upper unit had an adverse effect, and the impact often caused problems such as developer spraying out.

Furthermore, when performing maintenance or replacement of the image forming means, maintenance or replacement is performed by pulling out or rotating part or all of the image forming means in a direction other than the space opened during jam removal, so the installation space is limited. This requires a wide area and space, and also hinders miniaturization of the device.

In addition, in order to approach jam removal and maintenance from the same direction, multifaceted operations were required.

[Means for solving the problem (and operation)] According to the present invention, the transfer material is guided to the image forming means (the conveying means is configured to be detachable from the image forming means, and the image forming means is moved in the direction of this detachment). By configuring a part or the whole to be removable from the main body of the device, the jam removal opening is wide (and the maintenance and replacement work of the jam removal opening and the image forming means can be approached from the same direction, making it more compact. An image forming apparatus with good operability can be obtained.

〔Example〕

FIG. 1 shows a first embodiment of the present invention, and first, conveyance to the image forming means will be explained with reference to FIGS. 1 to 3.

A large number of cut sheets P are stacked on the paper feed tray 1,
The leading end of the cut sheet P is pressed against the feeding roller 4 and the idler roller 5 by the stacking plate 3 which is rotated by being biased by the feeding pressure spring 2 . The feeding roller 4 is a roller having a portion with a small diameter, and is shaped so that it can assume an initialization position in which it does not come into pressure contact with the cut sheet P and the conveying roller 6 at least at one point per rotation. In addition, idler rollers 5 that rotate smoothly around the feed roller shaft 7 are arranged near both ends of the feed roller 4, and the outer diameter of the idler roller 5 is slightly smaller than the maximum diameter of the feed roller 4. It is configured.

Also, the minimum paper size width I! The roller width may be set to be smaller than min in the width direction, and the roller may be divided into two as in this embodiment. The feed roller 4 is fixed to a drive shaft 7, and the drive shaft 7 is configured to be able to be controlled one rotation by a spring clutch 51 and a solenoid 52 at the end of the shaft.

Further, a swing cam 53.5 for swinging the loading plate 3 is located outside the maximum paper size Amax of the drive shaft 7.
3' is arranged, and the above-mentioned swing cam 5 of the loading plate 3
Cam follower 54.54 is located at the position corresponding to 3.53'.
' is fixed, so that the stacking plate 3 can be moved up and down by controlling the rotation of the drive shaft 7 to selectively suppress the stacked cut sheets P against the feeding roller 4 and the idler roller 5. Therefore, when the operator loads cut sheets into this device, the stacking plate 3 is lowered, as shown in Figures 1 and 3.
Since it is in the state shown in Figure (a), smooth loading of cut sheets is possible. In addition, after the cut sheet fed to the conveyance roller 6 section by the feed roller 4 is conveyed by the conveyance roller 6 and the idler roller 5, by lowering the stacking plate 3, the uppermost cut sheet being conveyed can be It can also prevent the cut sheets stacked below from being dragged out. The conveying roller 6 is swung by a oscillating arm 9 about a drive input shaft 8, and the feeding roller 4,
It is configured so that it can be pressed against the idler roller 5. The driving force to the conveyance roller 6 is provided by a drive gear 1 fixed to a drive input shaft 8.
12 and a conveying gear 113 fixed to the conveying roller 6. As in this embodiment, if the gear pair of the drive gear 112 and the conveyance gear 113 is arranged in the center of the conveyance roller 6, there will be no unbalance of the conveyance roller 6 due to the driving force, and stable pressure contact will be possible. becomes.

A friction member, for example, a separation pad 12 made of a rubber material containing cork, is in pressure contact with the feeding roller 4 and the idler roller 5, and is configured to pivotally support the central portion and press the central portion with a spring while equalizing the roller. Separate the cut sheets. The portion of the feeding path other than the separation pad 12 guides the cut sheet to the conveyance roller 6 by a paper guide shaped portion 10a formed on the base of the device. The device base 10 has a second cut sheet population 10b for introducing paper from a paper feed tray other than the paper feed tray 1 into the conveyance roller 6 and the idler roller 5 nip portion N.
has been established. This makes it possible to guide cut sheets from an optional feeding means such as a multi-sheet deck or cassette to the apparatus main body at the bottom of the apparatus main body, resulting in an excellent expandability of the apparatus.

The paper conveyance of the paper feed conveyance section of the present invention will be explained in order.

Before the paper feeding operation, when the motor M fixed to the device base 10, which is the drive source, starts rotating, the conveyance roller 6
The transport drive gear 55 fixed to the drive input shaft 8 rotates, and the drive input shaft 8. Drive gear 12. Rotation is transmitted to the conveyance roller 6 via the conveyance gear 13, and since the conveyance roller 6 is in pressure contact with the idler roller 5, the pair of the conveyance roller 6 and the idler roller 5 rotate. At that time, Idrakoro 5
Even if the cut sheet P is in contact with the cut sheet P, the structure is such that the frictional force between the cut sheet P and the separation pad 2 is greater than the frictional force between the idler roller 5 and the cut sheet P.
The cut sheet P is never fed.

In addition, during standby, the loading plate 3 has a swing cam 53.53' and a cam follower 54.54.
' Since the cut sheet P is in the pressed down position, it is not in contact with the idler roller 5. On the other hand, the rotation of the conveyance drive gear 55 causes a drive gear 56 fixed to the drive input shaft 8 and a drive gear 56 that is pivotally supported by a coupler arm 57 that rotates about the drive input shaft 8 to be rotated. The drive is transmitted to the coupler gear 58 that meshes with the coupler gear.

The coupler gear 58 is formed with a flange portion, and comes into contact with the flange portion of the paper feed drive gear 59 forming the aforementioned spring clutch 51, thereby ensuring backlash between the gears. The coupler gear 58 is disposed on the device base 10 side of the main unit, and the paper feed drive gear 59 is pivotally supported on the feed roller shaft, and is attached to a part K of the exterior cover having the paper feed transport fixing section. The drive is coupled and released by attaching and detaching a part of the exterior cover to the main body of the device.

The rotation of the paper feed drive gear 59 is transmitted to the feed roller shaft 7 via the spring clutch 51. When the solenoid 52 of the spring clutch 51 is OFF, the claw 52a of the solenoid 52 engages the claw 60a of the control ring 60 of the spring clutch, and the driving force of the paper feed drive gear 59 is not transmitted to the feed roller shaft 7. . When the solenoid 52 is turned on,
From the claw part 60a of the control ring 60 to the claw part 52 of the solenoid 52
a is removed, and the driving force of the paper feed drive gear 59 is transmitted to the feed roller shaft. In this way, one rotation control of the feed roller shaft is performed.

When the solenoid 52 is turned ON by the paper feed start signal, the claw portion 60a of the control ring 60 is released, and the paper feed drive gear 59
The driving force is transmitted to the drive shaft 7 via the spring clutch 51. Then, when the drive shaft 7 begins to rotate, as shown in Fig. 3 (
As shown in b), the swing cam 53 also rotates, the stacking plate 3 is pushed up by the paper feeding pressure spring 2, and the stacked cut sheets P are pressed against the feeding roller 4 and the idler roller 5. At this time, even if the paper is in contact with the rotating idler roller, it will not be fed out because the force between the paper and the paper is greater than the force between the idler roller and the paper, but the paper will not be fed out at the same time or slightly as the paper is being suppressed. Back and forth, the portion of the feed roller 4 whose outer diameter is larger than that of the idler roller 5 rotates to the portion that comes into contact with the cut sheet, so that the cut sheet is sent out by the feed roller.

Next, the cut sheets reach the separation pad 12 section, but only the topmost sheet of the cut sheets is led out to the downstream section of the separation pad 12 due to the relationship of the coefficient of friction. Immediately afterwards (,
The cut sheet reaches the nip N between the driven conveyance roller 6 and idler roller 5, and from this point on, the conveyance speed of the cut sheet is stabilized by the conveyance roller 6.

A sensor lever 13 is disposed downstream of the nip N between the conveyance roller 6 and the idler roller 5.
is pivotally supported by a swing arm 9 and rotates, and a photo interrupter 14 detects the leading edge of the cut sheet. As shown in the figure, this paper detection sensor is not only composed of a sensor lever 13 and a photointerrupter 14, but also a transmission type sensor or a reflection type sensor may be used. After the leading edge of the paper is detected, the cut sheet is transported by the transport roller 6 and the idler roller 5 to the vicinity of the photosensitive drum 15 of the image forming means. In this case, as in the present embodiment (by guiding the photoreceptor drum 15 to the photosensitive drum 15 using the guide-shaped portion 16a, which is a rib-shaped part of the developer casing 16 in the developing section, as a guide material, highly accurate conveyance can be achieved. It has the effect of being low in cost and easy to assemble.The toner image formed on the photoreceptor drum 15 by the image forming process described later is pressed against the photoreceptor drum 15 with a total pressure of 300g (Durham) to 1000g, drum 15
The image is transferred onto a transfer material by a transfer roller 17, which is a semiconductive rubber roller (102 to SΩ·cm) driven by a gear 15a disposed at the end of the photoreceptor drum 15 or driven by a photoreceptor drum 15. At this time, the transfer roller 17 is biased with DC500V to 1.5KV, which is opposite in polarity to the toner polarity, and the transfer material is conveyed between the photoreceptor drum 15 and the toner image on the photoreceptor. The image is transferred to a cut sheet P which is a transfer material. After the transfer, the cut sheet P is conveyed by the transfer roller 17, and the larger the absolute value of the bias applied to the transfer roller 17, the drier the transfer material, and the thinner and lighter the transfer material, the faster the transfer will be. Since the later cut sheet P tends to be attracted to the photosensitive drum 15 side, the cut sheet P is removed from the photosensitive drum 15 side.
As an auxiliary means for separating the images, a sheet material 18 made of Mylar or the like is placed close to or in contact with the photosensitive drum 15 from the transfer entrance guide portion 16a at the paper passing portion at the low reference end and several mm from the non-image area.
is arranged downstream from the transfer roller, photosensitive drum, and hentube section.

At this time, the transfer roller 17 has a diameter smaller than the thickness of the sheet material 18 in the sheet material 18 portion, and is shaped so that the conveying force of the transfer roller 17 is not applied to the sheet material 18.

On the transferred image surface side of the cut sheet P, the non-image area is guided by the sheet material 18 at the low reference edge described above, but in this embodiment, the non-image area guide material is placed on the conveyance path after transfer at the point when it is slightly separated from the photoreceptor drum. 19 is formed so that the end portion of the cut sheet separated from the photoreceptor drum 15 by the sheet material 18 is guided in place of the sheet material 18. With this, the sheet material 18, which is soft such as Mylar and is susceptible to bending, deformation, heat, etc., can be made as small as possible to prevent deformation. The side opposite to the transfer image surface is guided by a conveyance guide 20 that also serves as a fixing entrance guide, and the fixing section T
Lead the hekat sheet.

The fixing section T includes a fixing roller 21 made of an aluminum pipe whose surface is coated with Teflon and rotates under drive, and a halogen heater 22 as a heat source inside the fixing roller 21. The temperature of the fixing roller 21 is as follows:
The temperature is detected by a thermistor 23 that is in contact with the fixing roller in or near the paper passing section of the non-image area, and the temperature is detected by a DC controller 24 and an AC controller 25 in the electrical equipment section of the main body of the apparatus.
The temperature is controlled by In addition, as a safety measure in case of heater runaway, etc., the fusing roller 21 is set at the maximum paper feed speed of fm.
A non-contact thermoswitch 26 is disposed above the fixing roller 21 near the center of the ax. The distance between the thermoswitch 26 and the surface of the fixing roller 21 is determined by installing a plate spring 27 on the thermoswitch to constantly apply force in the direction of separation, and then moving the thermoswitch 26 close to the fixing roller 21 from the back side using an adjustment means such as a screw 28. It can be adjusted by In order to press the cut sheet against the fixing roller 21,
The pressure roller 29 with silicone rubber on the surface is 3 to 6K.
It is pressed against the fixing roller 21 with a total pressure of g, and is driven by the fixing roller 21. The transferred toner image on the cut sheet P is fixed as the cut sheet P passes through the nip between the heated fixing roller 21 and the pressure roller 29.

After fixing, the cut sheet P approaches the fixing roller 21 within 1 mm without contact, and the cut sheet P approaches the fixing roller 21 without contacting it.
The fixing roller 21 and the pressure roller 29
The paper is guided to the paper discharge paddle 31 located downstream of the pair. The paper ejection paddle 31 is made of an elastic body made of rubber or elastomer and has several separate protrusions. The tip of the separate protrusion of the paper ejection paddle 31 fits between the ribs of the fixing paper ejection upper guide 30 so as to overlap more than the rib tip, and the cut sheet P is ejected by straining the paper and the elastic force of the paper ejection paddle 31. The cut sheet P is pressed against the paddle 31, and the cut sheet P is conveyed by the frictional force of the separate protrusions as the sheet ejection paddle 31 rotates. The cut sheets P are then discharged to the outside of the apparatus and stacked on the paper discharge tray 32 located at the discharge port. Paper output tray 3
2 is configured to be easily removed.

The above-mentioned paper feeding, transporting, fixing, and paper discharging sections are supported on the apparatus base 10 by a shaft A, and are divided at the positions indicated by the dashed-dotted lines in FIG. 4, so that they can be opened and closed. FIG. 5 is a diagram when it is opened. At this time, remove the paper output tray 32,
The paper feed tray 1 is shown in a folded state with cut sheets stacked thereon removed.

Next, the image forming section--optical system will be explained.

The apparatus base 10 is configured as described above (a means for pivotally supporting a part of the exterior cover K having a paper feeding, transporting and fixing section on the A axis, and for guiding and positioning a cartridge such as a photosensitive drum 15, which is an electrophotographic image forming section to be described later). A laser beam optical system for imagewise exposure to the photosensitive drum 15 is also constructed on the apparatus base 10.

The laser beam optical system includes a polygon mirror 10, which is a rotating polygon mirror, on the rotation axis of a polygon motor 101 that rotates at high speed.
2 is fixed, and a semiconductor laser 103 irradiates the polygon mirror surface with a laser beam through a collimator lens 104, and the laser beam is reflected by the polygon mirror 102 surface.Then, the laser beam is irradiated onto the polygon mirror surface through a spherical lens 105 and an Fθ lens 106, and then is applied to a photoreceptor drum. 15 is irradiated with a laser beam. polygon mirror 102
By rotating , the generatrix direction of the photosensitive drum 15 is scanned, and the semiconductor laser 103 is turned on.

Dots can be formed on the generatrix of the photosensitive drum 15 by the OFF drive. At that time, the polygon mirror 102 performs laser scanning in the generatrix direction of the photosensitive drum 5 (referred to as main scanning).
In order to obtain the reference, a beam detector mirror 107 is provided in the center and outside of the image at the beginning of the scanning direction, and the laser light receiving surface 108a of the optical fiber 108 is provided at a position approximately equivalent to the distance from the photosensitive drum by reflecting the laser beam. The laser beam is guided to the laser light receiving element on the DC controller 24.

With this configuration, by performing beam detection, the reference timing for laser scanning is set to the image output timing, and by outputting an image signal to the semiconductor laser 103 using a clock from this reference timing, scanning in the main scanning direction is performed.

As mentioned above, the laser beam optical system has many high-precision parts such as lenses, high-speed rotating motors, and mirrors (which can cause image defects such as image shift, image blur, and poor perpendicularity due to positional misalignment with the photoreceptor drum 15). Therefore, in this embodiment, a polygon motor 101 having a polygon mirror as a photoconductor drum 15 and a laser beam optical system, a lens stand 109 for positioning a spherical lens 105 and an Fθ lens 106, and a beam detector mirror 107 are used. By configuring the semiconductor laser unit LU, which includes the beam detection optical fiber light receiving section 108a, the semiconductor laser 103, the semiconductor laser substrate 110, and the collimator lens 104, to be fixed to the device base 10, accuracy can be improved. By fixing the device base 10 to the device bottom plate 33 at three points R, R2R, the device base 10 has a structure that is strong against distortion or twisting of the bottom surface.

Next, the image forming section-electrophotography section will be explained.

The image forming means of this embodiment is in the form of a cartridge that integrates a photosensitive drum 15, a cleaner part C1, a secondary charging part T1, and a developing part.

-The next charging part T is 101 to 3Ω·c in this embodiment.
D on a semiconductive elastic body of about m, for example, the rubber roller 34.
C-600~-700V, AC1200~1800Vp
By applying a bias of p, the photosensitive drum 15 O
A PC drum can be charged to -600V to -700V. This rubber roller 34 is driven by the photosensitive drum 15 and is in contact with the photosensitive drum 15 with a pressure of several hundred grams. Next, image exposure is performed using the laser beam optical system described above, and the potential of the image exposure section becomes 150V to -150V. Next, the developing section moves the toner from the toner container section D1 filled with toner having the same polarity as the negative charge to the developing sleeve 36 by the agitating means 35.
The toner is pumped up and conveyed to the vicinity, and the surface of the developing sleeve 36 is coated with toner by the rubber blade portion 37 that is in contact with the developing sleeve 36, and the toner is coated with the toner on the surface of the developing sleeve 36.
By applying an AC bias while approaching the photosensitive drum 15 at a distance of 300 μ, toner is reversely developed on the exposed image portion of the photosensitive drum 15 (jumping development).

The toner image on the photoreceptor is then transferred to the transfer material as described above. The toner remaining on the photoreceptor after transfer passes through the scooping sheet 38 made of a Mylar sheet with a thickness of about 50 to 100 microns in the cleaner part C, and passes through the cleaner casing 39.
The photosensitive drum 15 is scraped off by a cleaning blade 40 attached to the photosensitive drum 15. The scraped off waste toner accumulates in the waste toner container portion C1 due to the movement of the toner as shown by the arrow in the figure.

The cleaned photosensitive drum 15 can be used for the next image forming process again. Cartridge is photosensitive drum 15
Considering the lifespan, cleaning blade life, and toner exhaustion, the cleaning blade is configured to be replaced with a new one after a certain amount of image formation. When replacing the cartridge, the cartridge is configured to be able to be pulled out and inserted to the side where a part K of the exterior cover that includes the paper feeding, conveyance, and fixing sections is opened. By opening part K of the exterior cover, the operator can take out the cartridge out of the main body at right angles to the direction of the drum generatrix. Further, by closing part K of the outer cover after inserting a new cartridge, the cartridge is reliably set in a predetermined position by the pressure of the transfer roller or the like.

FIG. 6 is a diagram showing how the cartridge CG is positioned on the device base.

The cartridge CG includes a drum bin 201 that pivotally supports the photosensitive drum 15 (dotted line), a guide portion 202a formed on the outer frame 202 of the cartridge CG, and a click spring portion 202b having spring properties on both sides. On the other hand, the device base 10 has a guide hole 10C for guiding the guide portion 202a, a click recess 10d for receiving the click spring 202b, and a positioning portion 10e for positioning the photosensitive drum 15 on both sides. The photosensitive drum 15 is driven by a drum drive gear 70 that is pivotally supported on the side surface of the device base 10 .

Contact portions 203 and 204 for high voltage, etc. are formed on the side surface of the cartridge opposite to the drum drive gear surface, and are configured to enable electrical connection with a contact portion (not shown) on the device base side. In the cartridge, the photosensitive drum is positioned with respect to the apparatus base 10 by the drum pin 201, and the rotational direction is also positioned with respect to the apparatus base 10 by the guide portion 202a.

[Other Examples]

In the above embodiment, the image forming means is a combination of a laser beam optical system and an electrophotographic section, and the maintenance and replacement work for the image forming means is replacing the electrophotographic cartridge. The present invention can also be applied to cases as shown in the following.

FIGS. 7(a) and 7(b) are cross-sectional views of an inkjet type non-impact printer, and the transfer material conveying means is a cart sheet P or roll paper inserted into the paper insertion slot K1.
The inkjet nozzles 303 are arranged in a nozzle array, such as 48 to 128 nozzles, in the paper feeding direction, and the nozzle array is arranged in a direction perpendicular to the paper feeding (main direction). (scanning direction), images are formed by 48 to 128 nozzle lines.

This main scanning direction is performed by sliding and reciprocating a moving shaft 304 supported in a direction perpendicular to paper feeding. The reciprocating motion is performed by a near motor or rotary motor (not shown), a belt, a wire, etc., and a head unit 305 is disposed on this movement axis for applying an electric signal to the inkjet nozzle 303 and scanning in the main scanning direction. has been done. This head part 3
05 is electrically coupled to a controller on the main body side of the apparatus via a cord 306. The inkjet nozzle 303 is moved on this head portion 305 in the main scanning direction. An ink tank 307 is disposed above the inkjet nozzle 303, and the inkjet nozzle 30
3. Supply ink. This ink tank 307 is also configured to be able to be removed independently from the inkjet nozzle 303. When replenishing ink or replacing the ink tank 307, it is possible to open the cover part K and take out only the ink tank 307 and replace it, or to take out the entire inkjet nozzle 303 and replace the inkjet nozzle 303 as shown in FIG. 7(b). The ink tank 307 is configured to be replaced or the ink tank 307 to be replaced. This rotational opening of a portion of the cover can also be used to remove paper in the event of a paper jam.

In addition, the conveying means may not only be rotated as in the above-mentioned embodiment, but may also be pulled away from the image forming means or the center of rotation may be moved upward, as shown in FIGS. 8(a) and (b). do not have.

In this case, there is an advantage that the stacked cut sheets can be left as they are without being removed, and there is no need to remove the paper output tray.

Further, the image forming means that is removed from the apparatus may be only a developing device, only a photosensitive drum, only a cleaner, or a combination thereof. Furthermore, it is not particular about image forming means using electrophotography.

In addition to providing the paper conveying means on the side surface as in the above embodiment, the conveying section may be provided on the top surface as shown in FIG. 9(a). An image forming means 501 such as an inkjet head is disposed in the main body 502 of the apparatus and performs image formation, and a conveying section 503 that conveys the paper P to the image forming means section is movable toward and away from the image forming means 501. In the example, it is configured to be rotatable around axis A. A paper feed roller 504, a platen roller, and a pair of ejection rollers 506 and 506' are supplied with driving force to transport the paper in the transport section 503. The paper P on the paper feed tray 507 is guided to the image forming unit, and after the image is formed, the paper P is discharged to the paper discharge tray 508.

At the time of maintenance such as replacement of the head 509 of the image forming means 501, ink replenishment, and replacement of the ink tank 510, and jam removal, the conveying section is opened as shown in FIG. 9(b).

〔Effect of the invention〕

As explained above, by configuring a part or the whole of the image forming means to be removable from the apparatus in the direction in which the conveying means that conveys the transfer material to the image forming means is removable, and by making it replaceable, jam removal and image forming are possible. There is an advantage that maintenance of the forming means can be performed from the same direction.

In addition, it is possible to have a large opening when clearing jams, and this opening can be used to replace and maintain the image forming means, making it possible to use space effectively. It has the effect of not moving.

Further, it is possible to make the inlet and outlet of the transfer material, the jam removal direction, and the maintenance direction in the same direction, and a compact device with a smaller installation area can be obtained.

Further, when the conveying means is located on the side surface and opened and closed, another device such as an image scanner can be installed on the top surface of the device, which has the advantage of reducing the installation area of the entire system.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a laser beam printer embodying the present invention, Fig. 2 is a detailed view of the paper conveyance section of a laser beam printer embodying the present invention, and Fig. 3 (a) and (b) are a cross-sectional view of a laser beam printer embodying the present invention. FIG. 4 is a top view of the laser beam printer embodying the present invention; FIG. 5 is an exploded view of the conveyance means of the laser beam printer embodying the present invention; FIG. Figure 7 is a front sectional view showing the paper conveyance unit in a released state in another embodiment; Figure 8 is a diagram showing the paper conveyance unit in a released state in another embodiment. FIGS. 9(a) and 9(b) are perspective views showing a jam removal state in a conventional example, and FIGS. 10 and 11 are perspective views showing a jam removal state in a conventional example. 1 ------- 1 paper feed tray 4 ------- 1 feed roller 6 - 1 conveyance roller 12 1 - Separation pad 15 ------- One photosensitive drum 20------ One conveyance guide 21------m Fixed fixing roller 29---One one Pressure roller 32------One discharge tray

Claims (3)

[Claims] (1) Image forming in which the image forming means is configured to be partially or completely detachable from the apparatus main body, and the conveying means for conveying the transfer material to the image forming means is configured to be detachable from the image forming means. An image forming apparatus characterized in that the image forming means is configured such that part or the whole of the image forming means can be removed from the apparatus in a direction in which the conveying means is removed. (2) Claim 1, characterized in that the transfer material is replenished and discharged from the direction in which the conveyance means is removed.
The image forming apparatus described in . (3) The image forming apparatus according to claim 1, wherein the conveyance means is detached in a substantially horizontal direction.