JPS59133577A - Picture forming device - Google Patents

Abstract

PURPOSE:To enable one direction processing of direction of insertion and direction of discharge of transferring material and facilitate removing of jammed transferring material by bending a carrying passage that carries the transferring material along peripheral face of an image carrier and along the direction of rotation. CONSTITUTION:As the carrying passage 37 of the transferring material P is made L-shape along the direction of advance to enclose a photosensitive body 21, the direction of discharge of the transferring material P is positioned in oblique direction to the photosensitive body 21, and loaded on a tray 38. Thus, one direction processing of direction of insertion and direction of discharge of the transferring material becomes possible. Removal of jammed transferring material is made easy by opening an opening 49 for maintenance by turning an access door 50 from the side of the transferring material 21 in the direction of arrow (a) through a pivot 51, and further, opening the carrying passage 37 by turning a frame in which a built-up unit 59 is incorporated in the direction of arrow (b) through a pivot 48.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to improvements in image forming apparatuses such as copying machines and laser printers.

[Technical background of the invention and its problems]

Conventionally, a laser printer has a configuration as shown in FIG. That is, the photoreceptor 2 placed in the center of the main body 1
A laser beam 5 uniformly charged by a charger 3 and scanned by a scanner 4 is focused and exposed onto the photoreceptor 2 by an FQ lens 6, and is connected to a power source as in the case of semiconductor laser beams. The photoconductor 2 is turned ON and OFF.
The charges are discharged by exposure, and an electrostatic latent image is formed.

This electrostatic latent image on the photoreceptor 2 is developed by a developing device 7 having a developing roller to which an appropriate bias is applied. This developed powder image is transferred to a transfer material by a transfer charger 8.
The image is transferred onto the transfer material P and fixed onto the transfer material P by the fixing device 9. On the other hand, the untransferred powder remaining on the photoconductor 2-F without being transferred to the transfer material P by the transfer charger 8 is removed from the photoconductor 2-F by the cleaning blade 1 of the cleaning device 10. In this way, the cleaned photoconductor 2 has its static charge removed by the static elimination lamp 12, and is returned to the charger 3 again.
The image forming process described above can be continued.

The transfer material P is taken out from the paper feed cassette J3 mounted at the bottom of one side of the main body 1 via the extension roller 14, and after its tip inclination is corrected by the aligning roller 15, the transfer material P is transferred to the photoreceptor 2. The photoreceptor is fed into a transfer portion formed between the transfer charger 8 and the photoreceptor 2 at the timing of image formation. Then, the transfer material P onto which the powder image has been transferred by the action of the transfer charger 8 is peeled off from the photoreceptor 2 by the peeling charger 16 and sent to the fixing device 9, and then transferred to the other side of the main body J via the paper ejection roller 17. It is designed to be discharged onto a tray J8 provided in the.

By the way, the configuration of this kind of conventional image forming apparatus has the following problems. That is, firstly, since the cleaning device is provided between the transfer means and the charging means, the cleaning device 10 occupies the volume around the photoreceptor 2. There are limitations.

For example, as shown in FIG. 1, the conveyance path 19 for the transfer material P is a straight path for the reasons described above. For this reason, when the transfer material P is jammed in the loading space, there is a problem that in order to remove the jammed transfer material P, it is necessary to separate it vertically with the transport path 19 as a boundary. The position of the cleaning means 10 as shown in FIG. 1 is an ideal position as a cleaning means, and for this reason, the transport path 19 of the transfer material P must also be a straight path. Also, since the insertion direction of the transfer material P and the ejection direction of the transfer material P are below the machine and in completely opposite directions, for example, one of the system equipment such as a laser printer
This is extremely disadvantageous for a single component device. For a worker sitting facing a CRT display,
Being able to discern what is being printed from the sitting position is one of the characteristics required as a matter of course for system equipment such as word processors, where all equipment is placed with their backs facing the wall. It is.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and its object is to form an image that enables unidirectional processing of transfer material in the insertion direction and ejection direction, and that makes it extremely easy to remove jammed transfer material. The aim is to provide equipment.

[Summary of the invention]

In order to achieve this object, the present invention has a conveyance path for conveying a transfer material that is curved so as to overflow in the direction of rotation of the image carrier.

[Embodiments of the invention]

The present invention will be described below with reference to an embodiment shown in FIGS. 2 to 8. FIG. 2 shows a laser printer as an image forming apparatus. In the figure, 205- is a main body, and inside this main body 20, there is provided a drum-shaped photoreceptor 2 as a supporting member, and around this photoreceptor 2 there is a charged plate extending in the direction of rotation of the photoreceptor 2. charger 2
2. Beam irradiation section of laser exposure device 23, developing device 24
, a transfer charger 25, a peeling charger 26, and a static elimination run 'f27 are arranged in this order.

The laser exposure device 23 is a laser emitter (not shown).
The laser beam 28 oscillated from the
The photoreceptor 2 is irradiated with the light through the second mirror 32 and the second mirror 32 . Further, the developing device 24 has a first developing roller 33 and a second developing roller 34.

On the other hand, a cassette 35 is installed in the lower part of the main body J, and the recording materials P are sequentially taken out one by one via a take-out roller 36.

The transfer material P taken out by the take-out roller 36 is provided on the upper part of the main body J via a conveyance path 37 formed by bending in a 17-shape along the circumferential surface of the photoreceptor 21 and the rotation direction. The tray 38 is now in general use.

Furthermore, a pair of aligning rollers 3 are provided on the upstream side of the conveyance path 37.
9 a + 39 b, but there is still a fuser 40 on the downstream side.
, and a pair of discharge rollers 41 a and 41 b are provided. Furthermore, aligning roller pairs 39a, 39b
Front and rear aligning roller front guide pair 42 a +
42b and a pair of pre-transfer guides 43a+43b, and a pre-fixing d guide 44 and a pair of pre-discharge roller guides 45a*45b are provided before and after the fixing device 40.

Further, - a pre-transfer sensor 46 corresponding to the pre-transfer guide pair 43a@43b;
A sensor 47 in front of the discharge roller is installed corresponding to the av45b.
has been done.

Further, the aligning roller front guide 42b, aligning roller 39b1 pre-transfer guide 43b1 transfer charger 25, peeling charger 26, and fixing device front guide 44 are mounted on a rotatable h frame (not shown) with the support ah48 as a fulcrum. The maintenance opening 4 is formed entirely in the main body 1 as shown by the two-dot chain line.
It is designed to be displaced to the 9 side.

In the figure, reference numeral 50 denotes an access door that opens and closes the maintenance opening 49 formed opposite to the conveyance path 37, and can be largely rotated outward about the support shaft 5 as shown by the two-dot chain line. The structure is as follows.

The ejection roller front guide 45th and the ejection roller 41h are still attached to a cover 53 that is pivotally supported on the main body J via a support shaft 52, and are rotatably displaced as shown by the two-dot chain line. There is.

The circumferential speed of the photoreceptor 2 is 133.3 wn/sec, and the diameter of the photoreceptor 2 is 78 m1.
It is 5 mW.

Next, the operation of this device will be explained.

When a printing command is transmitted to this device, first, the drive motor rotates and each part of the device starts moving, and at the same time, the electrification charger 22 and the static elimination lamp 27 are switched on. The laser beam 28 is scanned by the scanner 2q onto the photoreceptor 2, which is uniformly charged by the charger 22, and a negative electrostatic latent image is formed on the photoreceptor 21.

Now, let the rotational speed of photoreceptor 2 be ω radian/sea,
If the phase difference between the charger 22 and the first developing roller 33 is θ, then after θ1/ω seconds, the leading edge of the electrostatic latent image becomes the first
The developing roller 33 is reached. At this time, the first developing roller 3
A developing bias V is applied to the second developing roller 3 and the second developing roller 34 .

The developing bias V is the surface potential V of the unexposed part of the photoreceptor 2.
It is set to about half of o, Vo/2 (0〈V < V
o). Therefore, the exposed portion of the electrostatic latent image formed by the laser beam 28 attracts charged colored powder (toner) having the same polarity as the charging polarity, that is, the electrostatic latent image. Powder is not adsorbed to the unexposed area of
l), the negative electrostatic latent image is the first. and second developer 9 - developed by rollers 33 and 34; On the other hand, in synchronization with the movement of the electrostatic latent image on the photoconductor 2, the transfer material P is sent out from the cassette (transfer material storage container) 35 by the take-out roller 36 toward the pair of aligning rollers 39h and 39b. . Further, the transfer material P and the electrostatic latent image are registered and moved to the image transfer position by rotating the aligning roller pair 39ae39b at a preset timing. When the transfer material P reaches the image transfer position, that is, 0370 seconds after the development bias V is applied (here, 03 is the first development roller 33 and transfer charger 2
When the phase difference is 5.5, the transfer charger 25 and the peeling charger (transfer material static elimination charger) 26 are simultaneously switched on. In this way, from the back side of the transfer material P,
An electric charge is applied, and the potential of the transfer material P decreases, whereby the developed powder image on the photoreceptor 2 moves onto the transfer material P. After this, the transfer material P is removed by the peeling charger 26 of the AC charger biased at kV.
0- The particles separated from the photoreceptor 2 due to the electric current are moved up to the fixing device front guide 44 and are held by the heating rollers of the fixing device 40. Here, it is melted into a powder image on the transfer material P and fixed on the transfer material P. After that, the transfer material P is further transferred to the discharge roller pair 41.
a, 41b, is discharged from the apparatus, and is loaded onto the tray 38.

On the other hand, a part of the powder image transferred to the transfer material P remains on the photoreceptor 2. The behavior of the transfer residual powder on the photoreceptor 2 will be explained along with the process of using the photoreceptor 2 by turning the photoreceptor 2 as shown in FIG. According to the above explanation, each step is (1) →
(2)→(3)→(4) and the transfer step (4) has proceeded. Here, a method of repeatedly using the photoreceptor 2 of the apparatus of this embodiment will be described in the case where one more sheet is printed and recorded from the transfer step (4). Almost the majority of the powder image reversely developed on the photoreceptor 2 in the transfer step (4) (transfer efficiency about so%) is transferred to the transfer material P.
Transfer to. However, as shown in the figure, some of the powder remains on the photoreceptor 21, leading to the static elimination step (5). At this point, almost all of the adsorbed charges on the photoreceptor 2 are discharged. Thus, in the charging step (1), the photoreceptor 21. The remaining powder on the photoreceptor 2 is uniformly charged. However, the experimental results shown in FIGS. 4 and 5 revealed the following. When the photoreceptor 2 is charged from above the powder layer developed at a density of about D=1.3 on the photoreceptor 2, most of the charge passes through the powder layer. , photoreceptor 2
10 The fact is that the surface is uniformly charged. FIG. 4 is a schematic diagram of the experimental apparatus, in which a two-component developing roller 260 with a bias of +400V is applied to the photoreceptor 2 at D=1.
．． 3 shows a state in which black toner is uniformly adhered. Thereafter, the powder layer on the photoreceptor 21 is uniformly charged by the charger 6.

Next, the surface potential of the photoreceptor is measured from above the powder layer using a surface electrometer A. This is the value shown on the horizontal axis in FIG.

Furthermore, after this, the powder layer on the photoreceptor 2 is completely removed with a cleaning blade 62, and the surface potential of the photoreceptor 2 without the powder layer is measured with a surface electrometer B. This is the value on the vertical axis in FIG. The potential on surface electrometer A is +70
At 0V, the potential measured by surface electrometer B is about +500V. Therefore, in this state, the surface potential carried by the powder layer is approximately +200V.

However, in reality, due to frictional charging between Se on the photoconductor 2 and the urethane rubber of the cleaning blade 62, the photoconductor 2
Since it is known that powder is charged to about -100V, the actual surface potential carried by the powder layer is about 100V.

That is, it can be seen that even if a powder layer is deposited on the photoreceptor 2 at a concentration of D=1.3 and then charged, most of the charged charges will go to the surface of the photoreceptor 2.

Furthermore, as in this embodiment, the concentration of the transfer residual powder is as low as about 20% because the transfer efficiency is about 80%. Therefore, even if the photoreceptor 2 is charged from above the remaining powder layer on the photoreceptor 2 as in this embodiment, the photoreceptor 2 can be uniformly charged.
Most of the charged charges wrap around the underside of the remaining powder layer. Next, returning to the process of repeatedly using photoreceptor 2 in FIG. 3, in the next exposure step (2),
The above-described charged photoreceptor 2 is exposed to light. in this case,
It is possible that the aforementioned transfer residual powder exists in the exposed area. Therefore, the uniformly charged photoreceptor 21
After uniformly developing a peta (photoconductor density D = 1.3) L, the transfer efficiency is changed by changing the strength of the transfer charger 25, and the voltage is further increased to +750V from above the transferred powder layer. After being recharged as described above, the surface potential of the photoreceptor 2 was examined when it was exposed to laser light.

The results of this experiment are shown in FIG. The conditions at this time were a drum potential of 750 V after charging and before exposure.

Development density D of photosensitive drum = 1.3, development bias 400
V, drum sensitivity: half-decreased exposure amount: 1.5μυ2, laser power: 5.6μJ/cm” (drum surface).As can be seen from Figure 6, when the transfer efficiency is about 70% or more, the photoreceptor The surface potential of the photoconductor 21 drops to about 80 V. This is exactly the same as the residual potential of the photoconductor 21 during normal exposure. It can be seen that the transfer residual powder layer of No. It can be seen that there is no adverse effect.Thus, the next development step (3) is reached.Here,
FIG. 4 mentioned above.

Based on the experiments shown in FIGS. 5 and 6, and also in actual printed wiring experiments, the following was confirmed. In the two-component reversal development process as in this embodiment, the transfer residual powder present in the charged portion of the electrostatic latent image is removed from the photoreceptor 2 in the development step (3), and the electrostatic latent image is exposed to light.・Powder charged with the same polarity as the electric charge is attracted to the discharge part. In other words, it has been confirmed that the photoreceptor 2 is cleaned at the same time as the electrostatic latent image is developed. If you think about the reason for this, it will be as follows. First, in the charging step (1), the photoreceptor 2 was uniformly charged to +vo. After this, in the exposure step (2), even if there is a transfer residual powder layer in the exposed area, the surface potential of the exposed area of the photoreceptor 2 decreases to the exposure residual potential, as can be seen from the explanation in FIG. ing. On the other hand, in the unexposed area, most of the charged charges are uniformly attracted to the surface of the photoreceptor 21 under the transfer residual powder layer, as shown in the experiments shown in FIGS. 4 and 5. It is known that the surface potential of this unexposed area is +vo. Here, V=V
The developing rollers 33 and 34 biased at 0/2 (0<v<vo) rub the surface of the photoreceptor 2 on which the electrostatic latent image was previously formed. Therefore, the unexposed charged portion of the electrostatic latent image is transferred from the photoreceptor 21 to the developing roller 33.
An electric field towards 34 is generated. In this electric field, the previously mentioned unexposed transfer residual powder is placed, and since it is also charged with the same polarity as the band %l polarity, it is attached to and detached from the photoreceptor surface, and is attached to the developing roller side. 33, move to J4. This is the cleaning action of the photoreceptor 2. In the present embodiment, the first 'f! Due to the presence of the v-image roller 33 and the second developing roller 34, the above-mentioned cleaning action of the photoreceptor 2 is carried out very completely. From the viewpoint of the first developing roller 33, the second developing roller 34 can also be seen as a cleaning auxiliary means in terms of the cleaning action described above. On the other hand, in the exposure/discharge section of the electrostatic latent image, the developing roller 3393
An electric field is generated from the photoreceptor 4 toward the photoreceptor 2. In the two-component developer of this example, the carrier is held by the developing rollers 33, 34 by the force of the magnetic field of the developing rollers 33, 34, and the powder is frictionally charged with this carrier and charged to ■, and the mirror image charge of the carrier is (C)), it is electrically adsorbed to the carrier surface. This ■ charged colored powder is transferred to the developing roller 33 mentioned above.
．． The developing rollers 33 and 34 move toward the exposure/discharge area of the photoreceptor 2, and the mirror image charge (e) of the photoreceptor 2 causes this exposure to occur.・It is electrically attracted to the discharge part. That is, the electrostatic latent image is developed. Thus, in the method of repeatedly using the photoreceptor 2 of the apparatus of this embodiment, the photoreceptor is cleaned at the same time as development. Therefore, the transfer residual powder is not transferred to the transfer material P in the transfer process and causes blurring or scumming of the printed image.

Moreover, unlike the photoconductor cleaning method using a cleaning blade or a fur brush in order to electrically remove the transfer residual powder from the photoconductor, this embodiment does not cause adverse effects such as mechanical damage and film forming on the photoconductor 2. Not only is there no need for cleaning, but the cleaning means itself is removed from the image forming apparatus (electrophotographic recording apparatus) without increasing the diameter of the photoreceptor 2, making it possible to make the apparatus more compact.

Next, the stopping operation of each element of the apparatus at the end of printing one sheet will be described. FIG. 7 shows the ON-OFF timing of each component in the image forming process for one sheet printing and the drum static electricity removal process after the final immediate end. When the image creation process for one sheet printing is completed, that is,
When the laser exposure for printing one sheet is stopped, the charger 22 is turned off with a slight delay. Charger 2
The developing bias is turned off when the rear end of the charged portion reaches the position of the second developing roller 18-34.

Here, θ1' is the phase difference between the charging charger 22 and the second developing roller 34. (See FIG. 2) Therefore, the photoreceptor 2 will no longer continue to rotate and no image will be developed on the photoreceptor 2.

After a further 70 seconds (θ3+θl-〇l') has passed, the transfer of the developed image for one sheet is completed, so the transfer charger 25 is turned off. Here, 03 is the phase difference between the first developing row 233 and the transfer charger 25. but,
Further, the photoreceptor 2 continues to rotate, and at least 2π/ω
The stripping charger 26 is kept ON for more than 2 seconds, and the motor and static elimination run f2y are turned off only after 0270 seconds or more have elapsed since the stripping charger 26 was turned off.

In this final drum static neutralization process, the photoreceptor 2 is
Since it has a discharge polarity, the charge is completely removed, and image deterioration factors such as image blur caused by residual charge are eliminated. Furthermore, in response to the next printing command, the motor, charger 22, and charge removal lamp 27 are turned on almost simultaneously, but the developing bias is not turned on until the charged portion of the photoreceptor 2 reaches the first developing row 233. Therefore, since the developing bias is applied to the uncharged area, the area other than the image transfer area is not developed. In other words, in this embodiment, the image is not formed in areas other than the image transfer area both at the start of printing and at the end of printing. Since this is not carried out, it does not get stuck on the photoreceptor 2 that has passed through the transfer process and has no adverse effect on the printed image, so that a good image can always be obtained.

Furthermore, processing when the transfer material P jams inside the apparatus will be described. In this embodiment, the pre-transfer guide pair 43a,
43b, and a sensor 47 that detects that the transfer material P has passed through the discharge roller front guide pair 45a, 45b. By comparing the time interval set by a preset timer, it is determined and detected whether or not the transfer material P has jammed within the apparatus, and a jam signal is generated. Immediately when a jam signal occurs, all the components shown in Figure 8, including the motor, stop.
A jam indication is displayed on the operation panel. When the jam is displayed, the jammed transfer material P is removed from the apparatus. First, the access door 50, which is pivotally supported via the support shaft 5 diagonally below the photoreceptor 21, is removed from the almost side surface of the photoreceptor 2. The aligning roller front guide 42b is rotated further in the direction of the arrow (A) to open the maintenance opening 49, and furthermore, the aligning roller front guide 42b is mounted on a frame (not shown) that is pivotally supported via a support shaft 48 substantially below the photoreceptor 21.

Aligning roller 39b1 pre-transfer guide 43 transfer charger 25, peeling charger 26, fixing unit pre-guide 4
4 is assembled in the assembly unit 59 in the direction of the arrow exit.
Then, remove the jammed transfer material P from inside the device, and then
The jam signal is released by setting the assembly unit 59 and the access door 50 and inputting a reset signal. As described above, according to this embodiment, the transport path 37 for the transfer material P is formed in an L-shape so as to surround the photoreceptor 2 in the transport direction of the transfer material P, so that the transfer material J'-'), and the photoconductor access door 50 is located on the side of the photoconductor 2, and rotates and opens around the support shaft 5 diagonally below the photoconductor. instrument front guide 44, transfer charger 25,
An assembly unit 59 consisting of a peeling charger 26, a pre-transfer guide 43b, an aligning roller 39b, a pre-aligning roller guide 42b, etc. is integrated and rotates around a support shaft 48 located almost below the photoreceptor 2, and performs transfer. Since the material conveyance path 37 is wide open,
Jam disposal is extremely easy. This shape of the conveyance path 37 for the transfer material P was achieved by a new method of repeatedly using the photoreceptor 2, ie, developing and cleaning at the same time. Now, in the device in which the jam has been cleared and the jam signal has been released, the motor and charger 22 and charger 27 are turned on again for 5W, and the developing bias is set to 22-θ! After /ω seconds, the SW-ON is turned on again. In this way, the photoconductor 2 charges the charger 2 for at least 2π/ω seconds.
2 is turned on and rotated, and the developing powder image remaining on the photoreceptor 2 without being transferred due to a jam of the transfer material P is removed from the photoreceptor 2 by the first and second developing rollers 33 and 34. It is now being cleaned and cleaned. Further, after the charger 22 is turned off by SW-OFF, the developing bias is turned off by SW-OFF after 01770 seconds. In this way, if there is no printing command, the rotation of the motor will stop after the drum static elimination process is completed. Obviously, if there is a print command, the image forming process for one sheet printing shown in FIG. 7 will continue. In any case, in this way, even if the transfer material P jams, the untransferred powder layer on the photoreceptor 2 is completely removed and prepared for the next record printing, and the printed image is free from background blur and background stains. It is designed so that it will not have any other negative effects.

Now, according to this embodiment, the transfer path 3 for the transfer material P described above is
7 is L-shaped so as to surround the photoconductor 2 along this traveling direction, so that the discharge direction of the transfer material P is aligned with the photoconductor 21.
The transfer material P is often stacked in a tray 38 shown in FIG. 2. In this way, the insertion direction of the transfer material P and this cassette 35 into the main body 1, the processing direction of the transfer material P discharged outside the main body 1, and the content discrimination/reading direction become the same, so that the word processor, etc. It also has an ideal shape as a component of system equipment.

Note that the front part of the discharge roller 4)a rotates together with the idler 45a in the convex direction of the arrow as shown in FIG. 2 to open the conveyance path and facilitate the removal of the jammed transfer material P. .

Note that the present invention is not limited to the above embodiments. In other words, in the above embodiment, the electrostatic latent image developing device includes the first developing roller 33 and the second developing roller 34, and in the cleaning process at the same time as developing the electrostatic latent image, the unused parts of the photoreceptor 2 are removed. This makes the ability to remove residual toner from the exposed area and the ability to develop powder to the exposed area even more effective. However, the second developing roller 3
When the first developing row 233 is viewed as a developing and simultaneous cleaning means, the reference numeral 4 can also be regarded as a cleaning auxiliary means for further improving the cleaning ability of the first developing row 233. Thus, the second
For example, instead of the developing roller 34, a fur brush 65 shown in FIG. It is also possible to scrape off the transfer residual powder in the unexposed/charged portion by the first developing roller 33 to effectively remove -4. In addition, in this case, unlike the two-component developing roller, which uses metal chemical products such as magnets and sleeves, it can be used for fur brushes wrapped around paper tubes, so it can be constructed at a lower cost. Compared to the case where a cleaning process is provided between the transfer process and the electrostatic latent image forming process as in the conventional example, the removed powder can be collected and processed within the developing device, so this seems to be the case with the conventional example. 25- It is possible to prevent problems such as scattering of powder.

If we push the modification of Fig. 9 even further, the first
It is clear that cleaning means such as a cleaning blade 66 may be provided instead of the cleaning aid means of the fur brush 65 shown in FIG. 8, as shown in FIG. In this case as well, the ninth
It has the same advantages as the modified example shown in the figure, and also has the advantage that the surface of the photoreceptor 2 can be cleaned more completely than the cleaning means of the fur brush 65.

Next, a method for optically removing static electricity from the photoreceptor 2 will be described.

In the example, a photostatic charge removal process is provided between the transfer process and the charging process, but it is also possible to arrange the photostatic charge removal process between the development process and the transfer process as shown in FIG. Of course it's a good thing. As can be seen from the method of repeatedly using the photoreceptor in Fig. 3, in an electrophotographic recording device that uses a reversal development process, (1) → (2) → (3) → (
Even if the photoreceptor 21 is repeatedly used 26 as shown in steps 5')→(4)→(1), the memory of the charged potential on the photoreceptor 2 can be removed. In other words, the part to which the powder is attached, which is protected by photostatic charge removal, that is, the developing part, has already been exposed and discharged in the exposure process, and the powder is attached to the unexposed/charged part. Therefore, it is completely discharged in the static elimination step (5'). In this way, the static elimination process (5')
If it is placed between the development process and the transfer process, the following advantages exist compared to this embodiment and the conventional example. In the reversal development process, the area of the unexposed and undischarged portion of the pack ground is overwhelmingly larger than the development area. For this reason,
A phenomenon occurs in which the peeling of the transfer material P from the photoreceptor 2 immediately after the transfer step is worsened by the influence of the residual charge on the photoreceptor 2. However, by providing a photostatic charge removal process before the transfer process as shown in FIG. 11, there is an advantage that such factors that worsen the peeling of the transfer material P can be removed in advance, and the photostatic charge removal process can also be applied to any other part. There is an advantage that there is no need to arrange the image forming apparatus, and the volume of the image forming apparatus can be reduced while improving the performance of the image forming apparatus.

Furthermore, in this embodiment, a semiconductor laser beam is focused on the photoconductor 2 as the exposure beam, and is recorded by scanning in the axial direction of the photoconductor 2, but this is different from other laser beams. Of course, this is also possible depending on the exposure means. For example, although this is a well-known exposure method, an LED array may be used instead of a laser beam, and this light beam may be projected onto the photoreceptor 2 using a SELFOC lens or the like.

Further, the access door 50 may not be a rotating type, but may be a sliding type, for example, and the maintenance opening 49 side which is opened and closed by the access door 50 by rotating the assembly unit 59 around a support shaft. Although the transport path 37 is opened by displacing the transport path 37, it may be configured to be slidable by rails or the like.

In addition, it goes without saying that the present invention can be modified in various ways without departing from the gist of the invention.

〔Effect of the invention〕

As explained above, the present invention provides an image forming apparatus that once forms an image on an image carrier and then transfers the image to a transfer material, in which a conveyance path for conveying the transfer material is connected to the image carrier. The image forming apparatus is characterized in that the circumferential surface of the image forming apparatus is bent so as to be clearly curved in the direction of rotation. Therefore, it is possible to make the direction in which the transfer member is inserted into the device and the direction in which the ejected transfer member is handled, read, etc., the same, and the shape is suitable for use as a component of system equipment such as a word processor. In addition, the jammed transfer material can be removed very easily.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of a conventional image forming apparatus, FIGS. 2 to 8 show an embodiment of the present invention, FIG. 2 is a schematic sectional view of the entire image forming apparatus, and FIG. The figure is an explanatory diagram showing the image forming process, Figure 4 is a schematic diagram of the experimental equipment for investigating the process, Figure 5 is a diagram showing the charge injection characteristics to the photoreceptor surface through a single layer of toner, and Figure 6 is the photoreceptor. Figure 7 shows the photoreceptor exposure characteristics through the residual toner on the body 29, Figure 7 shows the image forming process and the photoreceptor static elimination process after printing, and Figure 8 shows how to clear the jam when the transfer material jams. FIGS. 9 to 11, which show the subsequent photoreceptor cleaning process, are schematic configuration diagrams showing other different embodiments of the present invention. P...Transfer material, 2...Image carrier, (photoreceptor), 2
5... Transfer means (transfer charger), 37... Conveyance path, 49... Maintenance opening, 5o... Access door, 42b, 43b l 44b... Conveyance path forming member (guide). Applicant's agent Patent attorney Takehiko Suzue 30- Figure 3 Figure 4 Figure 5 Surface t4 Tategu 1A11 Chapter 58.10.31 Amendment to the City Procedures 58.10.31 Showa 1920 Month Director General Kazuo Wakasugi ■, Indication of the case Japanese Patent Application No. 1977-7725 2, Name of the invention Image forming device 3, Person making the amendment Relationship to the case Patent applicant (307) Tokyo Shibaura Electric Co., Ltd. 4, Agent 6 Details subject to amendment Book 7, Contents of Amendment (1) In the specification, page 20, lines 3-4, the phrase "because it is applied," is corrected to "because it is not applied." (2) Similarly, on page 27, line 4, the phrase ``discharge caused by exposure'' is corrected to ``discharge caused by exposure.''

Claims (4)

[Claims] (1) In an image forming apparatus that once forms an image on an image carrier and then transfers this image to a transfer material,
An image forming apparatus characterized in that a conveying path for conveying the transfer material is bent so as to follow the circumferential surface of the image carrier and the rotation direction. (2) A transport path is formed along the side of the image carrier, and a maintenance opening that is opened and closed by an access door is formed opposite to the transport path. The image forming apparatus according to item 1. (3) The second aspect of the present invention is characterized in that the conveyance path forming member that forms the conveyance path and the transfer means that transfers the image on the image carrier onto the transfer material are movable toward the maintenance opening side. The image forming apparatus described in . (4) The image forming apparatus according to claim 2 or 3, wherein the direction in which the transfer material is discharged by the conveyance path is substantially vertically upward.