JPH10207156A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device capable of executing a laminating process without using an external device. SOLUTION: A large number of laminated sheets 33 constituted in such a manner that the outside of PET films cut in A4-size, etc., is coated with a hot-melt adhesive, for instance, are wound on a reel 34 like a roll and housed in the casing 31 of a laminater feeding device 30. A feeding roller 36 is linked with a sheet feeding drum 39, to be driven, so that the laminated sheets 33 wound like the roll are rotated. A separator 37 separates the laminated sheets 33 one by one. The separated laminated sheet 33 is fed downward by the feeding roller 36 and to a part, where the sheet feeding drum 39 faces a carrying roller 41 by a pair of feeding rolls 38. These feeding drum 39 and carrying roller 41 place the laminated sheet 33 on top of the surface of a paper sheet, while carrying the laminated sheet 33, in accordance with the movement of the paper sheet on a carrying belt 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus for protecting a printing screen and forming a high quality OHP image with a simple structure.

[0002]

2. Description of the Related Art Conventionally, an electrophotographic image forming apparatus has been known. In recent years, full-color image forming apparatuses have been put into practical use. Full-color image forming apparatuses are roughly classified into a single drum type and a multi-stage drum type (tandem type). The single-drum type repeats the paper transport process four times for one page to transfer four types of toner, whereas the tandem type transfers four types of toner in one paper transport process. Since the transfer is performed while being superimposed on paper, the processing speed is almost four times that of the single drum type. For this reason, in recent years, a tandem type system has attracted attention.

Incidentally, images printed (printed) by such a full-color image forming apparatus are often used for so-called presentations in offices, lecture halls, various waiting places, and the like. In this case, a projection device is used as a device that can be viewed by many people at the same time. When a color image is formed on OHP paper as the original,
Unlike a monochrome image, a color image is required to have good light transmittance for the purpose of projection using light.

In this case, the transparency of the solidified toner after fixing the image on the OHP paper is generally achieved by the smooth surface and no irregular reflection, the good degree of melting, and no turbidity inside. .

In order to satisfy such a demand, Japanese Patent Application Laid-Open No. Sho 60-52861 proposes an apparatus for obtaining smoothness of a printing toner surface of an OHP sheet by using an external device or the like. Also, JP-A-61-36756, JP-A-61-61756
JP-A-36-762 or JP-A-6-161324 proposes an image modification method as a post-process. Further, in Japanese Patent Publication No. 6-56536, by reducing both the heat fixing temperature during fixing and the sheet conveying speed, the toner can be sufficiently supplied within a range where no offset (transfer of the transferred toner and transfer to the fixing roller) occurs. A proposal has been made in which the resin is melted to obtain permeability.

[0006]

However, as a means for improving the transparency of the toner after fixing the above-mentioned printed OHP film, a transparent lacquer for smoothing the printed image surface as disclosed in JP-A-60-52861 is known. Methods such as application and use of a transparent adhesive tape involve technical implications in practical use, such as applying a transparent lacquer uniformly and thinly or adhering the tape over a large area of one page.

In order to perform lamination processing on the image surface of the toner after fixing, in addition to a printing device such as a printer, a laminator device which is another external device is used.
The ET material is coated with an adhesive such as hot melt, and the two ends (tips) of which the adhesive surfaces face each other are in a closed state, and the OHP image to be laminated is inserted therein and passed through a laminator device. The laminated paper is covered on the OHP image surface by bonding with a hot press. This means that the apparatus itself takes time (for example, 20 to 30 minutes) until the temperature is stabilized, and the feeding speed is slow (for example, 5 mm / sec). Also, when inserting OHP or the like into laminated paper, care must be taken to insert it correctly so that it does not protrude. For this reason, handling is troublesome and is not suitable for processing a large amount at present. In addition, the use of the laminator device, which is another external device, imposes an economic burden on the user and is not impressive.

[0008] The object of the present invention is to solve the above-mentioned conventional situation,
An object of the present invention is to provide an image forming apparatus that forms an image while transparently covering the image surface of a normal sheet or an OHP sheet only by the image forming apparatus without using a special external device.

[0009]

The construction of the image forming apparatus according to the present invention will be described below. The present invention operates an image forming unit to transfer a toner image onto the transfer-receiving sheet while transporting the transfer-receiving sheet supplied into the apparatus to a heat fixing device set to predetermined fixing conditions, The present invention is applied to an image forming apparatus in which the toner image is fixed on the transfer sheet by the heat fixing device while conveying the transfer sheet onto which the toner image has been transferred.

The image forming apparatus of the present invention is provided with a transparent covering film supply means for supplying the transparent covering film onto the unfixed transfer-receiving sheet on which the toner image has been transferred. The transparent coating film supply means is, for example, in claim 2
As described, it is configured to be detachable from the device main body.
In addition, for example, the image forming unit is configured to be compatible with the image forming unit. And, for example, claim 4
As described above, the image forming means is arranged in a plurality of rows in a multi-stage manner in the transport direction of the transfer-receiving sheet, and the transparent coating film supply means is the most downstream image forming means in the transport direction of the transfer-receiving sheet. Used in exchange for Further, the transparent covering film supply means is configured to supply a single leaf transparent covering film one by one, for example, as described in claim 5, and the transfer-receiving sheet is, for example, as described in claim 6, It is made of a transparent member.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view schematically showing an internal configuration of an image forming apparatus used in an embodiment, and FIG. 2 is a view showing the internal configuration of the image forming apparatus according to the first embodiment. FIG. 2 is a diagram illustrating the image forming apparatus in a state where a laminator sheet feeding device is provided.

First, the overall configuration of the image forming apparatus before the laminator sheet feeder is attached will be described with reference to FIG.
As shown in FIG. 1, this image forming apparatus (main device) 1
Has an opening / closing tray 2 on the rear surface (left side in the figure) and a paper cassette 3 detachable from the front of the apparatus (right side in the figure) at the lower part. A large number of sheets are placed and stored in the sheet cassette 3. An upper cover 4 is provided on the upper surface of the main unit 1.
It has. A power switch, a liquid crystal display device, a plurality of input keys, and the like are arranged on the front side of the upper cover 4 although not shown in the drawing. The upper cover 4 has a paper discharge tray 5 at the rear thereof together with the upper surface of the rear of the main body 1.

A paper transport belt (hereinafter simply referred to as a belt) 6 is disposed substantially in the center of the main unit 1 in a front and rear flat loop shape, and both ends of the loop in the horizontal direction are connected to a drive roller 7. It is held by a driven roller 8. The belt 6 is driven by a driving roller 7 and circulates in a counterclockwise direction indicated by an arrow A in the figure. In the upper circulation portion of the belt 6, four photosensitive drums 9 (9a, 9b, 9c,
9d) are arranged side by side in a multi-stage manner in the paper transport direction (from right to left in the figure).

A cleaner 11, an initialization charging brush 12, a writing head, and the like are arranged so as to surround each of the photosensitive drums 9 (typically, only the peripheral devices around the photosensitive drum 9 d are denoted by reference numerals). 13, a developing device 14, and a transfer brush 15 are arranged. Of these, developing unit 1
4, the photosensitive drum 9, the initialization charging brush 12 and the cleaner 11 form an image forming unit which is detachable from the main body device 1. When the image forming unit is mounted on the main body device 1, the gear of the photosensitive drum 9 is engaged with a drive system (not shown) of the main body device 1, and the contacts of the electrodes of each part are connected to the main body device 1.
Connect to the power supply contacts. Thus, the entire image forming unit is driven.

The above-mentioned writing head 13 is disposed on the back surface of the upper lid 4 via a support member 17, and descends as the upper lid 4 is closed, and the initialization charging brush 12 and the developing unit 14 are developed. It is positioned between the roller 16 and forms a recording section there. The developing device 14 has a developing roller 16 rotatably supported at the lower opening thereof in contact with the peripheral surface of the photosensitive drum 9 to form a developing section. The transfer brush 15 is pressed against the photosensitive drum 9 via the belt 6 to form a transfer portion.

On the downstream side of the lower circulation section of the belt 6,
A tension roller 18 is disposed so as to press against the back surface of the belt 6. The tension roller 18 is urged downward by an urging member (not shown) to press the belt 6 downward as indicated by an arrow B in the drawing, thereby absorbing the deflection of the belt 6 and causing the entire belt 6 to move to a predetermined position. It is stretched between the driving roller 7 and the driven roller 8 by tension.

At the upstream end of the upper circulating portion of the belt 6, an attraction roller 19 is in pressure contact with the driven roller 8 via the belt 6, forming a paper carrying portion. Suction roller 19
Is the paper (transferred sheet) that is carried into the paper carry-in section
Is pressed against the belt 6 while applying a suction bias to the belt 6 to electrostatically attract the paper to the belt 6.

The photosensitive drum 9 at the uppermost stream in the paper transport direction.
a the most downstream photosensitive drum 9d from the developing device 14 corresponding to a
, M (magenta) toner, C (cyan) toner, and Y (yellow)
B dedicated to printing of toner and black portions of characters and images
Each toner 21 of k (black) toner is stored respectively.

On the further upstream side (right side in the drawing) of the belt 6 in the transport direction, a standby roll pair 22 is disposed, and a paper feed guide path 23 is disposed below the standby roll pair 22. A roll pair 24 is provided. The paper feed end of the paper cassette 3 described above is located upstream (below) of the pair of feed rolls 24. The paper feed roller 2 is provided above the paper feed end of the paper cassette 3.
5 are provided. The paper feed roller 25 takes out one uppermost sheet stored in the paper cassette 3 and feeds it to the feed roll pair 24 every one rotation.

On the other hand, a fixing device 26 is provided downstream of the belt 6 in the sheet transport direction (left side in the drawing). Fixing device 2
Reference numeral 6 denotes a pressure roller, a heat roller, a separation claw, a peripheral cleaning device, an oil application roller, a temperature measuring device, and the like, which are assembled in a heat-insulating housing, and heats the toner image transferred on the paper to the paper surface. Fix it.

Main unit 1 located downstream of fixing unit 26
The rear inner surface also serves as the opening / closing tray 2 described above.
The opening / closing tray 2 opens and closes as shown by arrow C in the figure. The sheet on which the image was thermally fixed was discharged onto the opening / closing tray 2 when the opening / closing tray 2 was opened to the left in the drawing, and the opening / closing tray 2 was rotated rightward to be closed as shown in the drawing. At this time, the paper discharge tray 5 is passed through a paper discharge guide path 27 formed by the opening / closing tray 2 and a paper discharge roll pair 28 disposed at the end thereof.
Is discharged to

Further, between the belt 6 and the paper cassette 3, there is provided an electrical unit 29 on which an appropriate circuit board can be mounted, and a control device including a plurality of electronic components is mounted on the circuit board. The control device includes a controller and an engine. The controller includes a CPU (central processing unit), a ROM (read only memory), an EEPROM (rewritable read memory), a frame memory, an image data transfer circuit, and the like. Then, print data input from a host computer or the like is analyzed, print data is created, and transferred to the engine unit.

The engine unit includes a CPU, a ROM, and the like.
On the input side, data and command signals from the controller unit, the output of the temperature sensor, the output of the paper detection sensor, etc. are input, and on the output side, a motor driver that drives a motor (not shown), and the drive of the motor is transmitted to each unit. Driver that switches the driving system to be performed, a print driver that drives the write head 13 based on the print data, an initialization charging brush 1
2, developing roller 16, transfer brush 15, suction roller 19
And the like are connected to a bias power supply driver or the like that supplies a predetermined bias current. The engine unit controls the driving of each unit based on data and command signals from the controller unit, the output of the temperature sensor, the output of the sheet detection sensor, and the like.

Next, the operation of the image forming apparatus 1 having the above configuration will be described with reference to FIG. 1 again. First,
When power is supplied to the apparatus main body 1 and the paper quality, the number of sheets to be used, the print mode, and other designations are input as a key input or a signal from a host device to be connected, a paper feed roller 25 is driven by a drive mechanism (not shown). Makes one rotation, and feeds the paper loaded and stored in the paper cassette 3 to the standby roll pair 22 via the feed roll pair 24. Standby roll pair 22
Stops the rotation, abuts the leading edge of the sheet on a holding portion formed by a pair of rollers, stops the sheet from advancing, and waits for the conveyance timing.

Subsequently, the driving roller 7 rotates counterclockwise, and the driven roller 8 is driven to rotate similarly in the counterclockwise direction. As a result, the upper circulating portion of the belt 6 abuts on the four photosensitive drums 9, and the entire belt 6 circulates counterclockwise.

Along with this, the developing device 14 and the photosensitive drum 9
Are sequentially driven in accordance with the printing timing. The photosensitive drum 9 rotates clockwise. Initialization charging brush 1
Numeral 2 applies a uniform high negative charge to the peripheral surface of the photosensitive drum 9. The write head 13 performs exposure on the peripheral surface of the photosensitive drum 9 in accordance with an image signal to form a low potential portion. As a result, an electrostatic latent image composed of a high negative potential portion due to the initialization and a low negative potential portion due to exposure is formed. The developing roller 16 of the developing device 14 transfers the toner 21 to a low potential portion of the electrostatic latent image to form a toner image on the peripheral surface of the photosensitive drum 9 (reversal development).

At the timing when the leading end of the toner image on the peripheral surface of the photosensitive drum 9a at the most upstream position is rotated and conveyed to the point facing the belt 6, the printing start position of the paper coincides with the point. The standby roll pair 22 starts rotating and feeds the sheet to the sheet carrying-in section. Driven roller 8 and suction roller 19
Transports the fed sheet while holding it together with the belt 6. The sheet is attracted to the belt 6 and is conveyed to the first transfer section formed by the photosensitive drum 9a and the transfer brush 15.

The transfer brush 15 applies a transfer current output from a transfer bias power supply (not shown) to the sheet via the belt 6. The transfer current applied from the transfer brush 15 transfers the M (magenta) toner image on the photosensitive drum 9a to the paper. Subsequently, a C (cyan) toner image is transferred at the second transfer portion from the upstream formed by the photosensitive drum 9 b and the transfer brush 15, and further, the upstream formed by the photosensitive drum 9 c and the transfer brush 15 The Y (yellow) toner image is transferred at the third transfer portion from. Then, the photosensitive drum 9d and the transfer brush 1
5, the Bk (black) toner image is sequentially transferred at the most downstream transfer portion formed by the transfer roller 5.

The sheet on which the toner images of four colors have been transferred in this manner is separated from the belt 6 and carried into the fixing device 26. The fixing device 26 discharges the sheet backward while thermally fixing the toner image on the sheet. The sheet on which the image has been fixed is discharged with the toner image facing upward on the opened opening / closing tray 2 or guided by the closed opening / closing tray 2 with the toner image facing down on the upper discharge tray 5. .

FIG. 2 shows, as a first embodiment, a state in which a laminator sheet feeding device 30 is provided instead of one image forming unit in the image forming apparatus 1 operating as described above. FIG. 2 shows a state in which the image forming unit corresponding to the most downstream photosensitive drum 9d shown in FIG. 1, the write head 13 and the support member 17 are removed, and the laminator sheet feeding device 30 is arranged at the same position. is there. The removed lowermost image forming unit is an image forming unit that performs black printing. However, even without this image forming unit, there is no problem because the expression of black can be performed by mixing other three colors.

The image printing (printing) processing operation in this configuration is the same as in the above-described case. That is, the belt 6 sequentially conveys the sheets taken out of the sheet cassette 3 and fed to the sheet carry-in section to the downstream. The magenta toner image on the most upstream photosensitive drum 9a is transferred to the sheet, the cyan toner image on the next photosensitive drum 9b is transferred, and the yellow toner image on the photosensitive drum 9c is further transferred. The image is completed.

In this case, the laminator sheet feeding device 30 sends out the laminated sheet and synchronizes it with the leading edge of the conveyed sheet, in synchronism with the leading end of the conveyed sheet. The fixing device 26 melts and fixes the sheet on which the laminated sheet is placed by hot pressing in the same manner as in the normal image fixing, and melts the adhesive applied to the laminated sheet to bring the sheet into close contact with the sheet.

FIGS. 3A and 3B are enlarged views showing the configuration of the laminator sheet feeding device 30, and FIG. As shown in FIGS. 3 (a) and 3 (b), the laminator sheet feeding device 30 includes a base housing 31 and a cover 32. Inside the reel 34, a large number of laminated sheets are wound in a roll. The laminated sheet 33 supported on the upper end of the bracket 35 and wound
Feed roller 36 and laminating sheet 3 contacting the peripheral surface of
Separator 37, bracket 35 for separating 3 by 1
A feed roller pair 38 supported at the lower end of the sheet feed roller, a sheet feed drum 39 for feeding the laminate sheet 33 to the sheet surface instead of the black toner image, and a transport roller 41 for pressing the sheet feed drum 39 to transport the laminate sheet 33 , And a cleaner 42 for cleaning the surface of the sheet feeding drum 39.

The laminate sheet 33 is made of, for example, A
An adhesive such as hot melt is coated on the outside of the PET film cut into four sizes. In these laminated sheets 33, as shown in FIG. 4, the trailing end of the preceding laminated sheet 33a and the leading end of the succeeding laminated sheet 33b are
And a pair of transport rolls 38 so as to be separated by a distance L or more. Thus, the preceding laminate sheet 33a
The feeding roller 36 and the transport roll pair 38 will be described later by adopting a configuration in which the leading end of the subsequent laminate sheet 33b does not enter the feed roller 36 and the separator 37 when the rear end of the laminate sheet 33 has passed through the transport roll pair 38. Thus, while controlling with one clutch, it is possible to form both the state of waiting for the feeding of the laminate sheet 33 and the state of executing the feeding.

The feed roller 36 is driven in conjunction with a sheet feed drum 39 to rotate the laminate sheet 33 wound in a roll shape, as described later. The separator 37 separates the leading end of the laminate sheet 33 from the roll. The separated laminate sheet 33 is directly fed downward by the feeding roller 36. The delivery roll pair 38 delivers the laminate sheet 33 to a portion where the sheet feeding drum 39 and the transport roller 41 face each other. These series of operations are performed at a timing when the laminate sheet 33 overlaps a predetermined position of the sheet conveyed by the belt 6.

The sheet feed drum 39 and the transport roller 41 are
The laminate sheet 33 is layered on the paper surface while the laminate sheet 33 is being transported according to the transport (movement) of the paper. The cleaner 42 cleans the sheet feeding drum 39 by removing toner, dust and the like attached thereto.

The bracket 35 is rotatable about a support shaft of one roller 38a of the delivery roll pair 38 as a fulcrum.
It is always urged in a counterclockwise direction by an urging member (not shown). Therefore, the feed roller 36 and the separator 37
Are urged toward the center of the reel 34 and are constantly in pressure contact with the roll surface of the laminated sheet 33 which is consumed and its diameter decreases. Thereby, the separator 37 separates the laminate sheet 33 to the last one, and the feed roller 36
Sequentially feeds the separated laminated sheets 33 up to the last sheet.

FIG. 3B shows a state in which the laminate sheet 33 has been consumed and has disappeared. The cover 32 is openable and closable to the left around the support shaft 43 as indicated by a two-dot chain line 32 ′, and a laminate sheet 33 wrapped inside.
When the use is completed, the cover 32 is opened and a new laminated sheet 33 is replaced together with the reel 34.

The size and drive gear structure of the sheet feed drum 39 of the laminator sheet feeder 30 are the same as those of the photosensitive drum 9 of each image forming unit and the structure of the drive gear. Body drums 9a, 9b and 9c
Rotate at the same peripheral speed as. This sheet feed drum 3
The respective components in the laminator sheet feeding device 30 are driven in conjunction with 9.

FIG. 5 is a diagram showing a driving mechanism of the laminator sheet feeding device 30. Sheet feed drum 3 shown in FIG.
The 9 drum gear 51 is rotated by being engaged with a drive system (not shown) of the main body device 1. A clutch gear 52 meshes with the drum gear 51. The driving force transmitted from the drum gear 51 to the clutch gear 52 is transmitted to the delivery gear 56 via the clutch 53, the clutch shaft 54, and the clutch shaft gear 55. The delivery gear 56 is connected to the delivery roller shaft 5 by one roller 38a of the delivery roll pair 38.
7, a pulley 58 fixed to the delivery roll shaft 57, a timing belt 59 having one end suspended from the pulley 58, another pulley 61 having the other end suspended from the timing belt 59, The driving force is transmitted to the feed roller 36 via an idle gear 62, a feed gear 63, and a feed roller shaft 64 mounted coaxially with the pulley 61.

As described above, each part of the laminator sheet feeding device 30 is driven by using the drive system of the main body device 1 for driving the image forming unit as it is, and the feed roller 36 and the transport roller pair 38 are controlled by one clutch 53. The structure is relatively simple to control.

Next, a description will be given of a laminator sheet feeding device according to a second embodiment. FIG. 6 is a diagram illustrating an image forming apparatus provided with the laminator sheet feeding device according to the second embodiment. Also in this case, the image forming unit corresponding to the most downstream photosensitive drum 9d shown in FIG. 1 is removed, and the laminator sheet feeding device 70 is arranged at the same position. However, in the second embodiment, since the outer shape of the laminator paper feeding device 70 is configured to be the same as the outer shape of the image forming unit, if only the image forming unit is removed, the laminator paper feeding device 70 is immediately mounted. As in the case of FIG. 2, the print head 13 and the support member 17 do not need to be removed, and the operation is simpler. Also, in this case, since the removed lowermost image forming unit is an image forming unit that performs black printing that can be replaced with the other three colors, no problem occurs in full-color printing. Except for the laminator sheet feeding device, the overall configuration and operation are almost the same as those in FIG. However, in this case, the driving of the lowermost print head 13 and the transfer brush 15 is stopped.

FIGS. 7A and 7B are enlarged views showing the structure of the laminator sheet feeding device 70. FIG. As shown in FIG. 2A, the laminator sheet feeding device 70 includes a sheet feeding drum 72 at the same position as the photosensitive drum of the image forming unit in a housing 71 having the same outer shape as the image forming unit. The cleaner 73 is provided at the same position as the initialization charging brush and the cleaner of the forming unit. Then, a large number of laminated sheet bundles 75 are accommodated in a sub-case 74 having the same shape as that of the developing device of the image forming unit by being curved in a downward U-shape, and are partitioned by a partition plate 76 disposed inside the U-shape. This prevents the laminated sheet bundle 75 from deforming.

A feeding roller 7 is provided in the lower opening of the sub-case 74.
7, and a separating pad 78 is disposed in pressure contact with the feeding roller 77. One end of the laminated sheet bundle 75 is pressed by the bottom plate 79 near the contact portion between the feeding roller 77 and the separating pad 78, and is pressed against the feeding roller 77. The feeding roller 77 rotates clockwise in the figure to feed one of the uppermost sheets (the inside of the U-shape) of the laminated sheet bundle 75 to the sheet feeding drum 72. The separation pad 78 prevents the second or less laminate sheet from being fed along with the feeding by the frictional force.

The lower end of a lever-shaped sheet sensor 81 mounted coaxially with the feed roller 77 detects a feed start end and a feed end end of each laminated sheet. The rotation of the upper end portion to the left or right in response to the detection by the lower end portion of the sheet sensor 81 is converted into an electric signal by the photo sensor 82 and notified to the control portion of the engine portion, and the feeding timing of the laminate sheet is controlled. You. The fed laminate sheet is supplied to the sheet on the belt 6 by the sheet feed drum 72 and the conveying roller 83 pressed against the sheet feed drum 72.

FIG. 7B shows a state in which the laminate sheet bundle 75 has been consumed and has disappeared. When the laminate sheet bundle 75 has been used up and has been used up, the cover 74-1 is opened as shown in FIG. 7B, and the partition plate 76 is rotated clockwise to the position indicated by the two-dot chain line 76 'in the figure. When you do
The bottom plate 79 is pushed to the position indicated by the two-dot chain line 79 ′ in the drawing by the projecting portion 76-1 at the lower end of the partition plate 76, and the press-contact state with the feeding roller 77 is released. This makes it possible to easily set the leading end of the new laminate sheet bundle 75 at the feeding position close to the contact portion between the feeding roller 77 and the separating pad 78.

FIG. 8 is a view showing a driving mechanism of the laminator sheet feeding device 70. Also in this case, the drum gear 85 of the sheet feeding drum 72 shown in FIG. An idle gear 86 meshes with the drum gear 85. The driving force transmitted from the drum gear 85 to the idle gear 86 drives the feed roller 77 via the clutch gear 87, the clutch 88, and the feed shaft 89.

As described above, also in this case, each part of the laminator sheet feeding device 70 is driven by using the drive system of the main unit 1 for driving the image forming unit as it is. Feed roller 77
The feeding timing is controlled via the clutch 88.

In the above embodiment, the paper for forming an image is not specifically described, but the paper may be plain paper or OHP paper. When an image is formed on ordinary paper, the above-described lamination processing is used to protect the image from damage and dirt. When an image is formed on an OHP sheet, the above-described lamination may be used to improve the image quality of the OHP image. .

The laminator paper feeder is replaced with the most downstream image forming unit. However, all the image forming units are used as they are, and the laminator paper feeder is fixed to the most downstream image forming unit. It may be arranged separately between the vessels. Further, paper (an OHP paper or the like) on which an image has been fixed in the normal printing mode first can be laminated again in the laminating mode. In this case, better light transmittance can be obtained.

Further, the size of the laminated sheet is made slightly smaller than in the normal case so that the leading end position does not protrude from the paper even if the leading end position is slightly back and forth or the whole is skewed and the position varies. By doing so, it is possible to prevent such an obstacle that the adhesive of the protruding portion of the laminate sheet at the time of fixing is welded to the fixing device.

[0052]

As described above in detail, according to the present invention, since the laminator sheet feeding device is provided in the image forming apparatus so as to be compatible with the image forming unit, an image can be formed by another image forming unit. Meanwhile, the image surface can be subjected to lamination processing by the laminator paper feeder in the same process, thereby enabling the lamination processing at the same time as the printing operation without using other external devices and the image forming apparatus itself. In addition, laminating can be performed at low cost without trouble and without trouble.

Further, since the laminating member is merely supplied in the form of a sheet and is superimposed on the image surface, there is no need for a cutting process and no trouble such as inserting paper into the laminating member. Lamination can be performed continuously.

[Brief description of the drawings]

FIG. 1 is a side sectional view schematically illustrating an internal configuration of an image forming apparatus used in an embodiment.

FIG. 2 is a diagram illustrating the image forming apparatus in a state in which the laminator sheet feeding apparatus according to the first embodiment is disposed so as to be replaced with one image forming unit.

FIGS. 3A and 3B are enlarged views showing a configuration of a laminator sheet feeding device according to the first embodiment.

FIG. 4 is a configuration diagram of winding a laminate sheet according to the first embodiment.

FIG. 5 is a diagram illustrating a drive mechanism of the laminator sheet feeding device according to the first embodiment.

FIG. 6 is a diagram illustrating an image forming apparatus in a state where a laminator sheet feeding apparatus according to a second embodiment is disposed so as to be replaced with one image forming unit.

FIGS. 7A and 7B are enlarged views showing a configuration of a laminator sheet feeding device according to a second embodiment.

FIG. 8 is a diagram illustrating a driving mechanism of a laminator sheet feeding device according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image forming apparatus (main body apparatus) 2 Opening / closing tray 3 Paper cassette 4 Top lid 5 Paper discharge tray 6 Paper transport belt 7 Drive roller 8 Follower roller 9 (9a, 9b, 9c, 9d) Photoconductor drum 11 Cleaner 12 Initialization charging brush 13 Writing Head 14 Developing Device 15 Transfer Brush 16 Developing Roller 17 Supporting Member 18 Tension Roller 19 Suction Roller 21 Toner 22 Standby Roll Pair 23 Feeding Guide Path 24 Feed Roll Pair 25 Feed Roller 26 Fixing Device 27 Discharge Guideway 28 Discharge Roll Pair 29 Electrical Unit 30 Laminator Feeder 31 Base Housing 32 Cover 33 Laminated Sheet 34 Reel 35 Bracket 36 Feed Roller 37 Separator 38 Send Roll Pair 39 Sheet Feed Drum 41 Transport Roller 42 Cleaner 43 Support Shaft 51 Drum Gear 52 clutch A 53 Clutch 54 Clutch shaft 55 Clutch shaft gear 56 Delivery gear 57 Delivery roll shaft 58 Pulley 59 Timing belt 61 Pulley 62 Idle gear 63 Feeding gear 64 Feeding roller shaft 70 Laminator paper feeder 71 Housing 72 Sheet feed drum 73 Cleaner 74 Sub-housing 74-1 Cover 75 Laminated sheet bundle 76 Partition plate 76-1 Projecting portion 77 Feed roller 78 Separation pad 79 Bottom plate 81 Sheet sensor 82 Photo sensor 83 Transport roller 85 Drum gear 86 Idle gear 87 Clutch gear 88 Clutch 89 Feed shaft

Claims (6)

[Claims] An image forming means is operated to transfer a toner image onto a transfer-receiving sheet while the transfer-receiving sheet supplied to the apparatus is conveyed to a heating and fixing device set under predetermined fixing conditions. An image forming apparatus that fixes the toner image on the transfer sheet by the heating and fixing device while conveying the transfer sheet onto which the toner image has been transferred; An image forming apparatus comprising: a transparent covering film supply unit for supplying a transparent covering film onto a sheet. 2. The image forming apparatus according to claim 1, wherein said transparent covering film supply means is detachably attached to said apparatus main body. 3. The image forming apparatus according to claim 1, wherein the transparent covering film supply unit is configured to be compatible with the image forming unit. 4. The image forming means comprises a plurality of image forming means arranged in parallel in a multi-stage manner in a transport direction of the transfer sheet, and the transparent covering film supply means includes a most downstream image forming means in the transport direction of the transfer sheet. The image forming apparatus according to claim 1, wherein the image forming apparatus is used in exchange for: 5. The image forming apparatus according to claim 1, wherein said transparent covering film supply means supplies a single leaf transparent covering film one by one. 6. The image forming apparatus according to claim 1, wherein the transfer sheet is made of a transparent member.