JPS6353549B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic copying apparatus that continuously runs a long roll of electrophotographic photosensitive paper to take pictures, and in particular uses a dry method using powder as a developing method and a pressure-based method as a fixing method. The present invention relates to an electrophotographic copying apparatus that uses a fixing method to take pictures while continuously running a long roll of photosensitive paper.

Conventionally, various types of copying machines have been provided that use powder development and pressure fixing methods, but all of them use photosensitive paper in the form of a single leaf, or even if they use photosensitive paper in the form of a roll, they cut the paper immediately after the start of shooting. This is similar to the case of ordinary single-leaf photosensitive paper, and there is no paper that uses a pressure fixing method and runs continuously as a long paper. In the case of the pressure fixing method, there is a problem that the photosensitive paper runs in a meandering manner, wrinkles occur, and in severe cases, the photosensitive paper can be cut. This is because it has become an important issue. In the case of conventional copying machines, in order to prevent wrinkles, a pair of fixing rollers are pressed against each other at a slight angle, rather than in parallel, to reduce the effect of deflection of the fixing rollers due to the strong pressure required for fixing. ing. However, in this method, since the directions of the axes of the pair of fixing rollers do not match, the running of the photosensitive paper becomes unstable and causes meandering. In addition, in conventional copying machines, there is no means to control when the leading edge of photosensitive paper, which has become a single leaf, is pinched by the fixing roller and begins to be pressed against it, so the state of sandwiching differs each time a photograph is taken, and the axis If the paper is sandwiched at an angle to the paper, it will run diagonally, and in severe cases, it may run off the fixing roller, or it may get wrapped around the fixing roller and cause a paper jam. It also had the problem of wrinkles. Furthermore, in conventional copying machines, the leading edge of the photosensitive paper runs across the magnetic brush of the developer, breaking the magnetic brush and depositing developer on the back side of the photosensitive paper. Because of its shape, it can be in a free state depending on the traveling position, and therefore, the contact state with the developing device fluctuates from time to time, which also has the disadvantage that it is difficult to stabilize the image quality.

The present invention provides an electrophotographic copying apparatus that eliminates the drawbacks of conventional copying machines as described above. In particular, it is most suitable for a copying machine that has an automatic document feeder and also performs continuous high-speed photography. There are various possible uses for such a copying device, but
It is particularly suitable for saving labor in tasks that conventionally relied on handwriting, such as for recording slips, checks, etc., or for creating proofs of delivery, delivery receipts, etc. for registered mail.

Hereinafter, the present invention will be explained based on illustrated embodiments.

The basic structure of the embodiment of the present invention is as shown in FIGS. 1 and 2, including a long roll-shaped photoreceptor,
A holding means for holding the photoreceptor, a back tension applying means for applying a predetermined back tension to the photoreceptor, a winding diameter detecting means for detecting the winding diameter of the copying machine, and a guiding means for guiding the photoreceptor; A charging device that uniformly charges a part of the photoconductor, an exposure device that projects an image of an original onto the charged photoconductor, a developing device that develops the exposed photoconductor, and a developing device that transfers the developed image to the photoconductor. It consists of a fixing means for fixing the copying machine to the machine, a cutting means for cutting the copying machine into a predetermined length after fixing, and a discharging means for ejecting and accumulating the copying machine.The specific structure of each part is explained below. Explain in detail.

The photoreceptor used in the examples of the present invention is a photosensitive paper in which a conventionally used semiconductor photosensitive layer mainly composed of zinc oxide (ZnO) is coated on a long roll paper. This long roll of photosensitive paper will be simply referred to as copy paper 1 hereinafter. The copy paper 1 is wrapped around the outer periphery of a paper tube 2, and the paper tube 2 is held in place by a copy paper holding means.

The holding means mainly includes a reel shaft 3, a reel hub 4, a reel flange 5, a swing lever 6, and an engagement plate 7. As shown in FIG. 3, the reel shaft 3 is fixed to the main body plate 8, and a reel hub 4 is rotatably supported on the reel shaft 3 by a bearing 9, and is mounted with its axial position determined by a ring 10. ing. The reel hub 4 is formed to be slightly smaller than the inner diameter of the paper tube 2, has a part of its outer periphery cut out, and has a swing lever 6 swingably supported by pins 11 at both ends thereof. An engagement plate 7 is attached to the swing lever 6.
is fixed parallel to the reel hub 4, and its engagement plate 7
is located in the notch of the reel hub 4. The engagement plate 7 has an edge portion 12 formed over a portion of its entire length. The swing lever 6 is moved to the second position by the engagement spring 13.
The engagement plate 7 is biased in the direction of the arrow A in the drawing, and the edge portion 12 of the engagement plate 7 is located outside the outer diameter of the reel hub 4 when copy paper 1 is not loaded. Furthermore, when the copy paper 1 is loaded, the edge portion 12 of the engagement plate 7 and the paper tube 2 are in contact with each other, and when the copy paper 1 runs in the direction of arrow B in FIG.
2 bits in, so that the copy paper 1 and the reel hub 4 rotate as one. Reel axis 3
The reel flange 5 rotatably supported by a bearing 18 is configured to be interlocked with the reel hub 4 by a connecting pin 14 fixed to the reel hub 4, and is in contact with the end surface of the copy paper 1. , the mounting position of the copy paper 1 is regulated.

The back tension applying means consists of a reel gear 15, a connecting gear 16, and a back tension generating member 17. The back tension generating member 17 is mainly composed of a coil and a magnetic material, and generates a constant torque according to the energized current by the magnetic flux when the coil is energized and the hysteresis loss when the magnetic material is rotated. Generally, the product name is ``Hysteresis Brake'' [Ogura Clutch
Co., Ltd., etc.) and is widely available to the general public.

The reel gear 15 is fixed concentrically to the reel flange 5, and has a back tension generating member 17.
It is configured to transmit torque to the reel hub (holding means) 4 which is provided in the reel hub (holding means) and meshes with the connecting gear 16.

The winding diameter detection means mainly includes a winding diameter detection lever 19,
A method of detecting the winding diameter by bringing the winding diameter detecting roller 20, which includes a winding diameter detection roller 20 and a variable resistor 21 and is rotatably supported by one end of the winding diameter detection lever 19, into contact with the outer periphery of the copy paper 1. The winding diameter detection lever 19 is rotatably supported on the main body main plate 8 by the detection shaft 23 so as to follow changes in the winding diameter, and
The winding diameter detection lever 19 is biased by the winding diameter detection spring 22 in the direction of arrow C in FIG.
4 and a gear 25 that meshes with the variable resistor 21.

The guide means includes first and second guide rollers 26 and 27 rotatably supported. The first and second guide rollers 26 and 27 are arranged parallel to the reel shaft 3 and the fixing roll described later. The second guide roller 27 is provided with flanges 28 and 29 at an interval slightly wider than the width of the copy paper 1, and one flange 28 is connected to the main body plate 8 described above.
The copy paper 1 is guided in parallel with the reel flange 5.

The charging means is the same as that commonly used in ordinary copying machines. That is, this is a shield case 30 made of a conductive material and grounded.
, a charging wire 31 made of a tungsten wire stretched therein, and a high voltage power source (not shown) connected to the charging wire 31, and the shield case 30 has an opening facing the copy paper 1. It is provided.

The structure of the exposure means is basically the same as that commonly used in ordinary copying machines. That is, it consists of an imaging lens 43, an illumination lamp 44, and a reflecting mirror 46 for introducing reflected light from an original 45 into the lens 43. In this embodiment, the illumination method is to apply a high voltage from an exposure power source (not shown) to a flash discharge lamp filled with a rare gas such as xenon for a short time in order to expose the moving copy paper 1. An instantaneous exposure method is adopted in which discharge light is emitted, and the light is emitted repeatedly at intervals synchronized with the traveling speed of the copy paper 1. The originals 45 are sequentially supplied to an exposure position by an unillustrated original supplying means, and after being exposed, are sequentially sent to a stacker (not shown).

The developing means has basically the same structure as that used in general copying machines, and includes a developer 47 made of a mixture of toner and carrier or magnetic toner, a hopper 48 for replenishing the developer 47, and a magnetic brush. It consists of a forming roller 49. A magnetic brush forming roller 49, which forms a magnetic brush by attaching and fluffing the developer 47 supplied from the hopper 48 to the surface thereof, is rotatably installed inside the sleeve 50 made of a non-magnetic material. , and a magnet roll 51 in which a large number of magnetic poles are arranged. The developer 47 is sequentially supplied from the hopper 48 onto the surface of the sleeve 50 by rotating the magnet roll 51 by a motor (not shown), thereby forming a uniform magnetic brush.

In the embodiment of the present invention, the developing means further includes a developing gap regulating means to regulate the gap between the surface of the sleeve 50 and the copy paper 1 during development. The developing gap regulating means includes a positioning member 52 and a back plate 53.
It consists of The positioning member 52 is made of a non-magnetic material, has an arcuate portion having the same radius as the sleeve 50, and is disposed at both ends of the surface of the sleeve 50 outside the width of the copy paper 1. The back plate 53 is rotatably supported and disposed so as to come into contact with and lock the positioning member 52 on a straight line connecting the outer periphery of the second guide roller 27 and the outer periphery of a first fixing roller 80, which will be described later.
It regulates the development gap between the magnetic brush and the copy paper 1, and is configured to come into contact with the back surface of the copy paper 1 and be grounded during the charging and exposure process. The back plate 53 includes the main body plate 8 and the main body sub-plate 5 as shown in FIG.
A connecting lever 56 is fixed to one end of the rotating shaft 55, and a plunger 58 of a solenoid 57 is installed at the tip of the connecting lever 56. Plate biasing spring 5
9 is stretched and biased in a direction to bring the back plate 53 into contact with the positioning member 52. In a normal state, the back board 53 remains stationary at a position where it abuts on the positioning member 52. In the embodiment of the present invention, copy paper 1
normally maintains a state in which it has passed through a developing gap and a fixing means to be described later, but when the leading edge of the copying paper 1 is passed through the developing gap when replacing the copying paper 1, etc., the back plate 53 is magnetically Moving away from the brush forming roller 49, the back plate 53 and the sleeve 5
The structure is such that a gap larger than the developing gap is provided between the two. This is because when trying to pass the leading edge of the copy paper 1 between the back plate 53 and the sleeve 50, which maintain a normal gap, the developer 47 may adhere to the back side of the copy paper 1 or adhere to the surface of the sleeve 50. This is to prevent the developer 47 from spilling downward and staining the fixing roller and the like below.

Further, in the embodiment of the present invention, the developing means is provided with copy paper loading guide means. When passing the leading edge of the copy paper 1 as described above, if the back plate 53 is moved away from the magnetic brush forming roller 49 or if the copy paper 1 is curled, the magnetic brush may break, causing developer to spill or copying. There is a risk that the copy paper 1 will adhere to the back side of the copy paper 1, and means are provided for forming a guide groove 60 for guiding the copy paper 1 on the back plate 53 which is running away.

As shown in FIGS. 6 and 7, the copy paper loading guide means includes a guide piece 62 having an L-shaped corner 61 for forming a pair of guide grooves 60, which is rotatably supported on the back plate 53, and is rotatably supported on the back plate 53. Piece 63, bearing plate 64, support shaft 6
5. It is composed of a rotation spring 66 and a reversing pin 67. The bearing plate 64 is fixed to the back plate 53 and rotatably supported by the bearing plate 64 by a rotating piece 65. A guide piece 62 is fixed to the rotating piece 63, and a rotating spring 66 is stretched between it and the bearing plate 64.

During normal copying operation, the locking portion 68 at one end of the rotating piece 63 comes into contact with the reversing pin 67 fixed to the main body plate 8 and the main body sub-plate 54, and the rotating piece 63 comes into contact with the rotating spring 66, and 6, the guide piece 62 is separated from the back plate 53 and no guide groove 60 is formed. When the leading edge of the copy paper 1 is passed through the developing gap, the back plate 53 rotates and separates from the sleeve 50, and the force of the rotation spring 66 causes the rotation piece 63 to rotate in the direction of arrow E in FIG. , guide piece 6
6 is rotated so as to approach the lower side of the back plate 53, and a guide groove 60 is formed between the L-shaped corner 61 and the back plate 53.

As shown in FIGS. 8 and 9, the fixing means includes a first fixing roller 80, a second fixing roller 81, the first fixing roller 80 being rotatably supported by a bearing 82, and the main body main plate 8 and the main body A pair of fixed side plates 83 fixed to the sub-plate 54, a stay 85 fixed to the fixed side plate 83 with screws 84, and a second fixing roller 81 are rotatably supported and swingably supported by the stay 85. A pair of movable side plates 86
and a pressure spring 88 which is installed between the fixed side plate 83 and the movable side plate 86 and presses the first and second fixing rollers 80 and 81 into contact with each other with a predetermined pressure by means of an adjustment screw 87 screwed onto the fixed side plate 83. ing. 1st
The fixing roller 80 is formed into a drum shape with a diameter at the center larger than the diameter at both ends, and is driven by a main motor 91 via a gear 89 provided at the end and a motor gear 90 meshing with the gear 89. ing. The second fixing roller 81 is similarly formed into a drum shape, and both fixing rollers 80 and 81 are parallel to each other and are connected to the reel shaft 3 and the guide rollers 26 and 2.
7 are arranged in parallel. Both fixing rollers 8
0 and 81 are pressed by a pressure spring 88 with the pressure necessary to fix the image on the copy paper 1.
This pressing force is usually 20 to 30 kg/cm, which is quite strong pressure. Therefore, in the case of a cylindrical fixing roller where each part has the same diameter, it will bend, and the pressing force will be stronger at the ends and weaker at the center.
In severe cases, poor fixing may occur. Furthermore, if there is a difference in the pressure contact force at both ends, there is a risk that meandering will occur, and that the difference in pressure contact force between the center and the ends will cause sagging and wrinkles. However, in this embodiment, the drum-shaped fixing rollers 80 and 81 are used, and the pressure contact force is uniform over the entire length when a predetermined pressure is applied, so that the above-mentioned problem does not occur. Good fixing is achieved. Furthermore, since both fixing rollers 80 and 81 are in parallel pressure contact, the running direction is also stable.

In the embodiment of the present invention, a copy paper insertion means is provided to press the copy paper 1 against the fixing rollers 80 and 81 in an appropriate state. That is, in this embodiment, both the fixing rollers 80 and 81 are pressed in parallel with each other to obtain a uniform pressure contact force, but when the copy paper 1 is held between the fixing rollers 80 and 81, the axis line and If it is not inserted at right angles and clamped,
The copy paper 1 is caused to run in an inclined direction and eventually comes off both fixing rollers 80 and 81. In order to prevent this, in this embodiment, copy paper 1
When inserting the fixing rollers 80 and 81, the copy paper inserting means separates the fixing rollers 80 and 81 to create a gap, through which the copy paper 1 can be passed smoothly.
This copy paper insertion guide means includes a roller separating means, a latch means, a braking means, as shown in FIGS. 9 and 10.
It consists of an introducing means and a paper detecting means. The roller separating means includes an eccentric portion 93 inserted into an opening 92 of the movable side plate 86, and an eccentric shaft 94 rotatably supported by the fixed side plate 83. The latch means includes a control lever 95 provided at one end of the eccentric shaft 94, a latch plate 96 pivoted to the control lever 95, and a latch pin 9 fixed to the sub-plate 54 of the main body.
9, a latch spring 97 that biases the latch plate 96 toward the latch pin 99, and a release lever 98 that operates the latch plate 96 in the release direction. The braking means includes a one-way clutch 100 provided at the other end of the eccentric shaft 94, a gear 101 connected via the one-way clutch 100,
It consists of a braking gear 102 that meshes with the gear 101, a speed increasing gear train 103 connected thereto, and an impeller 104 provided at the end thereof. As shown in FIG. 8, the introduction means includes an introduction cam 105 disposed on the eccentric shaft 94, and an introduction roller 106 that is swingably supported by the stay 85 and that can come into contact with the introduction cam 105 and is disposed at one end. Arm 1
07, an introduction roller 108 rotatably supported at the other end and whose surface is made of rubber, an introduction roller spring 109, and a guide plate 1 for guiding the copy paper 1.
It consists of 10. The paper detection means is disposed in front of the cutting means described later in the traveling direction of the copy paper 1, and includes a light emitting body 115, a photoreceptor 116, and a detection circuit for detecting the arrival of the copy paper 1 and stopping the traveling of the copy paper 1 (see FIG. (not shown).

The cutting means for cutting the copy paper 1 into a predetermined length is
It is the same as the rotary cutter 117 commonly used in general copying machines, and is composed of a fixed blade 118, a rotary blade 119 that rotates in one direction, and a drive mechanism (not shown) for making one rotation intermittently. ing.

A discharging means for discharging the copy paper 1 cut into a predetermined length to an exit includes a pair of rotatable rollers 120, 121 and a belt 1 stretched between the rollers 120 and 121.
22 and a collection box 123, the roller 120 rotates in conjunction with the first fixing roller 80,
121, the copy paper 1 on the belt 122 is sent to a collection box 123 and collected therein.

Next, the operation will be explained. As shown in FIG. 2, the leading edge of the long roll of copy paper 1 has passed through a predetermined path and has been cut by the rotary cutter 117 at the point where the previous operation has been completed.

When the start switch (not shown) is operated, the high voltage power supply (not shown) is first activated, and a high voltage is applied to the charging wire 31 to cause corona discharge and uniformly spread the surface of the corresponding copy paper 1. electrify it accordingly. At the same time, the main motor 91 rotates, rotates the first fixing roller 80 via the motor gear 90 and the gear 89, and causes the copy paper 1 held between it and the second fixing roller 81 to run. At the moment the charged surface reaches the exposure position, a high voltage is instantaneously applied to the lamp 44 from an exposure power source (not shown) to cause it to emit light, and the image of the original 45 is transferred to the copy paper 1 through the lens 43. An image is formed on top and instantaneous exposure is performed. The exposure means then repeats instantaneous exposure at intervals synchronized with the traveling speed of the copy paper 1 and the document supply means (not shown), thereby forming an electrostatic latent image on the copy paper 1 charged by the charging means. At the same time as the exposure means operates, the magnet roll 51 is also rotated by a motor (not shown), causing the developer 47 to slide on the magnetic brush forming roller 49 while fluffing it. The copy paper 1, whose development gap is kept constant by the development gap regulating means, travels while its surface is rubbed by a magnetic brush, and development is performed. Thereafter, the powder image that is visualized by being pressed by both fixing rollers 80 and 81 is fixed on the copy paper 1, cut as appropriate by the cutting means, sent by the discharge means, and sent to the collection box. 123 to complete the process, and the same operation is repeated thereafter.

To end the photographing, a stop switch (not shown) is operated to stop the high voltage power supply (not shown), stop the corona discharge, and stop the operation of the exposure means. The developing and fixing means continues its operation,
The configuration is such that all operations are stopped when an image of the document 45 at the time when a stop switch (not shown) is operated is created.

Here, the traveling of the copy paper 1 will be explained in detail. The first fixing roller 80 rotates at the same time as a start switch (not shown) is operated on the copy paper 1.
It is held between the second fixing roller 81 and sent. At this time, back tension is applied to the copy paper 1 by the above-mentioned back tension applying means. The winding diameter of the copy paper 1 at that time is detected by the winding diameter detecting means, and the corresponding resistance value is obtained by the variable resistor 21, and the back tension generating member 17 is detected by an electric circuit as shown in FIG. A predetermined current is applied from a DC power source 53 to generate a predetermined torque and a constant back tension is obtained.
To explain in more detail, the back tension is
T _B (Kg), the winding diameter of the copy paper 1 is D (mm), and the generated torque of the back tension generating member 17 is M _B (Kg-mm).
Then, the relationship is T _B = 2M _B /D (Kg), and since the winding diameter D changes in order to keep the back tension T _B constant, the generated torque M _B must be changed accordingly. I understand that. In the embodiment of the present invention, the change in the winding diameter of the copy paper 1 is replaced by a change in the resistance value of the variable resistor 21, and the current applied to the back tension generating member 17 is changed accordingly to change the generated torque. The back tension is kept constant. When a long sheet of copy paper 1 is pressure-fixed and run continuously, the important items are not only to dispose fixing rollers with uniform pressure contact force in parallel, but also to apply an appropriate back tension. In experiments conducted by the present inventor, it has been found that if no back tension is applied, even if the fixing roller is pressed in parallel with uniform pressure, it is not possible to eliminate the occurrence of meandering and wrinkles; It was confirmed that stable running was achieved with no meandering or wrinkling when applying .

In experiments conducted by the present inventor, running became stable when a back tension of 1.5 kg or more was applied. However, when applying back tension, there is a method of applying back tension by pressing a pad or the like against the outer periphery of the copy paper, as was commonly used in conventional copying machines, or a method of applying back tension between a pair of rollers that generates braking torque. In the clamping method, back tension acts on the outermost periphery of the copy paper or on the copy paper itself while it is running, and it is nearly impossible to obtain a uniform back tension over the entire width of the paper. The difference in back tension causes meandering and wrinkles, making it difficult to run smoothly.

In the embodiment of the present invention, the torque generated by the back tension generating member 17 is transmitted to the holding means,
Insert the engagement plate 7 of the holding means into the paper tube 2,
The structure is such that back tension is applied to the entire copy paper 1 through the paper tube 2, so that no unreasonable force is applied to the outermost copy paper 1 during travel, and uniform back tension is applied over the entire width of the paper. The shock absorber is working and stable driving is achieved. In addition, since a moderate back tension is applied, the exposure position
Even at the development position, the copy paper 1 maintains a uniform flat state, and a stable image without out-of-focus or uneven development is obtained. Furthermore, wrapping the copy paper 1 around a roller is also effective in preventing wrinkles.
Also in the embodiment of the present invention, the first fixing roller 80
The copy paper 1 is wrapped at an angle of about 90 degrees around the second guide roller 27, and the second guide roller 27 is also wrapped at an angle of about 90 degrees or more to prevent the occurrence of wrinkles. This also prevents the occurrence of meandering.

Next, the operation when replacing the copy paper 1 will be explained. After inserting the copy paper 1 into the holding means, when a paper loading switch (not shown) is operated, the solenoid 57 is energized and the plunger 58 is attracted by the solenoid 57. The connecting lever 56 attached to the plunger 58 rotates in the direction of arrow F in FIG.
3 also rotates in the direction of arrow G in FIG. 5, leaving the magnetic brush forming roller 49 to form a gap wider than the developing gap. By rotating the back plate 53, the contact between the locking portion 68 of the rotating piece 63 and the reversing pin 67 is released, so that the rotating piece 63 moves in the direction shown by the arrow E in FIG. 7 due to the force of the rotating spring 66. Therefore, the guide piece 62 rotates in a direction approaching the back plate 53,
A guide groove 6 is formed between the L-shaped corner 61 and the back plate 53.
form 0. In this state, the back plate 5 is positioned away from the magnetic brush forming roller 49 as shown in FIG.
3 and the L-shaped corner 61 of the guide piece 62, a guide groove 60 is formed between the magnetic brush 3 and the L-shaped corner 61 of the guide piece 62. The structure is such that the leading edge of the paper 1 can pass below the developing means.

Next, the operation of the copy sheet inserting means for inserting the copy sheet into the fixing means will be explained. Figures 1 and 10
In the figure, when the operating lever 95 is rotated in the direction of arrow H, the eccentric shaft 94 is rotated in the same direction, and while the eccentric portion 93 is in contact with the opening 92 of the movable side plate 86, the movable side plate 86 is rotated. Rotating in the direction of arrow I in FIG. 10, the second fixing roller 81 is separated from the first fixing roller 80, and a gap through which the copy paper 1 can pass is formed as shown in the figure. The operating lever 95 is provided with a latch plate 96 having an engaging groove.
The eccentric shaft 94 rotates in the direction of arrow J in FIG. 10 due to the force of the second fixing roller 81 being engaged with the latch pin 99 and being pressed against it by the force of the pressure spring 88, and attempts to return to its original position. Lock movement. Therefore, a gap is maintained between both fixing rollers 80 and 81.

In this state, in the case of normal operation, the cam roller 106 provided on the introduction roller arm 107 is pressed by the introduction cam 105, and the introduction roller 108, which was positioned so as not to be pressed against the first fixing roller 80, is moved by the eccentric shaft. Introducing cam 1 integrated with 94
05 rotates and releases the pressure on the introduction roller arm 107, the introduction roller spring 109 presses the first fixing roller 80. The first fixing roller 80 is the above-mentioned paper loading switch (not shown).
It rotates in this state. Therefore, when the leading edge of the copy paper 1 that has passed through the developing means is inserted to the contact point between the first fixing roller 80 and the introduction roller 108, the copy paper 1 held between the rollers 80 and 108 runs and moves along the guide plate 110. Then, it passes through the gap between the first and second fixing rollers 80 and 81. At this time, press the paper loading switch (not shown).
In conjunction with this, the current to the back tension generating member 17 is cut off, and no back tension is applied.

The copy paper 1 that has passed through the fixing means passes through the cutting means and reaches the paper detection means, which activates a detection circuit (not shown) in order to block the light emitted from the light emitter 115 to the photoreceptor 116. , first fixing roller 80
The rotation of the copy paper 1 is stopped, and the loading of the copy paper 1 is completed.

Thereafter, when the slidable release lever 98 provided on the operating lever 95 is pushed in the direction of arrow K in FIG.
The eccentric shaft 94 rotates in the direction of arrow L in FIG. 0, disengages from the latch pin 99, rotates in the direction of arrow J in FIG.
1 are brought into pressure contact with each other, and the introduction roller 108 is released from the first fixing roller 80 by the introduction cam 105.

At this time, since the pressing force between the fixing rollers 80 and 81 is strong, the eccentric shaft 94 returns rapidly due to this force, and there is a risk that the fixing rollers 80 and 81 will come into contact with each other in a shocking manner. In order to prevent this, the embodiment of the present invention is provided with a braking means. The operation of the moving means will be explained below. The eccentric shaft 94 is connected to a gear 101 for braking via a one-way clutch 100 that transmits power only when the eccentric shaft 94 returns and rotates in the direction of arrow J in FIG. Gear 102 and speed increasing gear train 1
03 are continuous, and an impeller 104 is provided at the end thereof. When the eccentric shaft 94 rotates in the direction of arrow J in FIG. 10, the impeller 104 rotates at high speed.
The eccentric shaft 94 is braked by the air resistance to gradually return to rotation, and the second fixing roller 81 is gradually brought closer to the first fixing roller 80, and both fixing rollers 80, 81 are brought into gentle pressure contact.

Through the operations described above, the copy paper 1 is inserted into the developing means and fixing means and stopped at a predetermined position.

The copy paper 1 is inserted into the guide groove 60 formed on the back plate 53.
The fixing rollers 80 and 81, which are provided with a gap, pass through the developing gap without breaking the magnetic brush or adhering the developer 47 to the back surface.
The second guide roller 27 and the first fixing roller 8
0 and is inserted while being guided.
It is inserted in the correct state without wrinkles at right angles to the axis of the fixing roller 80, is pressed against it by the braking means without applying any impact force, and is regulated to the regular developing gap by the return of the back plate 53, completing preparation for copying. After that, if a start button (not shown) is operated, good copying will be performed in the same manner as described above.

Another function of the above-mentioned copy paper insertion means will now be explained. The copy paper insertion means is normally activated when replacing the copy paper 1, but it is also effective in the unlikely event that a paper jam occurs during copying operation. When a paper jam occurs, the rotation of the main motor 91 is stopped, the traveling of the copy paper 1 by the first and second fixing rollers 80 and 81 is stopped, and the operating lever 95 is moved in the direction of arrow H in FIG. The second fixing roller 81 is rotated to escape, and a gap is formed between the two fixing rollers 80 and 81. In this state, when the copy paper 1 is rotated along the roll in the direction of arrow M in FIG. The machine rotates and rewinds the part that caused the paper jam into a roll, completing the paper jam clearing process. At this time, regardless of the presence or absence of torque from the back tension generating member 17, the paper tube 2 and the engagement plate 7 are free to escape.
You can always rewind freely. In conventional copying machines, the fixing roller remains in pressure contact with the paper, making it difficult to dispose of the paper knots, which cannot be ejected forward or backward, and must be removed by rotating the fixing roller intermittently. However, in the configuration of the embodiment of the present invention, a gap is created between the fixing rollers, so this problem can be dealt with very easily.

The above is an explanation of the configuration and operation of the embodiment of the present invention. In this embodiment, a configuration has been described in which one copy is made from one original, but as is obvious, if the exposure means (lens system) is modified and a slit means is provided, it is possible to make one copy from one original at the same time. It also serves as a device for making two copies. It is also clear that the copying apparatus according to the basic structure of the present invention can be made by using other materials than zinc oxide for the photoreceptor and by employing a different image forming process. Further, in the embodiment, a document feeding means and an instantaneous exposure method were adopted, but there is no problem in using a slit exposure method using a continuous light emitting lamp, and a structure in which the document is ejected as a long document without cutting it into a predetermined length can also be used. It is clear that there is no problem as well. As described above, the present invention
The present invention is applicable not only to the scope limited to the embodiments, but also to various applications.

As is clear from the above description, the present invention uses a fixing means that applies back tension to a long sheet of copy paper, guides it through a guide roller parallel to the fixing roller, and presses a drum-shaped roller in parallel. Because it is configured to run while fixing, stable running of the copy paper is achieved without wrinkles or meandering in the copy paper, which is the most important issue for this type of device: stability of the running system. This is something that can be achieved. In particular, since the copy paper is wound and guided around guide rollers and fixing rollers that are arranged parallel to each other, more stable running can be achieved.

Furthermore, since back tension is applied to the paper tube of the copy paper, even back tension acts evenly over the entire width of the copy paper while it is running, resulting in more stable running.

Furthermore, the roll diameter of the copy paper is detected by directly contacting the outer periphery of the copy paper roll with a radius detection roller, and the necessary current is applied to the back tension generating member according to the diameter to generate the required torque. Since a constant back tension is always applied, the charging, exposure, development, and fixing processes are performed in a constant and uniform state from the beginning to the end of the copy paper, and stable images are obtained with stable running. It is something that can be done.

Furthermore, according to the present improved invention, the developing gap during development is regulated by the contact between the positioning member provided on the sleeve and the rotatable back plate, so that a constant developing gap can be reliably produced. It is possible to stabilize the image. Moreover, when replacing the copy paper or when there is a paper jam, rotating the back plate in the direction away from the positioning member prevents the tip of the copy paper from breaking the developing magnetic brush or causing developer to adhere to the back side of the copy paper. There are no such problems.

When loading copy paper, the fuser roller is released from pressure and the back plate is moved away from the developing magnetic brush to form a guide groove, so it can be inserted perpendicularly to the axis of the fuser roller and in the optimum condition. The magnetic brush can be inserted without destroying the magnetic brush and without causing developer to adhere to the back side of the copy paper, thereby stabilizing both the image and the running.

Since the introduction roller is pressed against the fixing roller only when the pressure contact is released, there is no problem during normal operation, and copy paper can be inserted easily only when paper is inserted.

In addition, the completion of paper loading is detected by the paper detection means consisting of a light emitter and a photoreceptor, so the insertion operation is easy and the paper can be used effectively without inserting extra copy paper. No unreasonable force is applied for detection, and this has an effective effect in achieving stable running.

Furthermore, since it has a latch means that maintains the fixing roller in a released state, it is easier and safer to load copy paper, and it can also be used to deal with paper jams, which is useful in practice. In addition to this, when the copying apparatus is not in use, the fixing rollers can be separated from each other to avoid deformation of the rollers and the adverse effects of stress caused by strong pressing force.

Furthermore, when the fixing roller is released and then brought into pressure contact again, the braking means gradually moves the fixing roller and brings it into pressure contact, so there is no chance of excessive force acting on the fixing roller, bearings, etc. and damaging them.
It has the effect of increasing the lifespan,
Furthermore, when the fixing roller is released, the braking means does not operate and the operation is easy, which is a practical effect.

[Brief explanation of drawings]

FIG. 1 is a perspective view of essential parts showing the internal configuration of an embodiment of the present invention, FIG. 2 is a sectional front view of essential parts of the embodiment,
FIG. 3 is a plan sectional view of the holding and guiding means in the same embodiment, FIG. 4 is an electric circuit diagram of the back tension applying means, and FIG. 5 explains the operation of the copy paper loading guide means in the same embodiment. 6 and 7 are plan views for explaining the operation,
FIG. 8 is a side view of the fixing means in the same embodiment, FIG. 9 is a plan sectional view thereof, and FIG. 10 is a side view for explaining the copy sheet insertion operation. 1 is a copy paper, 2 is a paper tube, 3 is a reel hub, 5 is a reel flange, 7 is an engagement plate, 17 is a back tension generating member, 19 is a winding diameter detection lever, 21 is a variable resistor, 26 is a first guide Laura, 27 is the second
Guide roller, 30 is a shield case, 47 is a developer, 50 is a sleeve, 52 is a positioning member, 53
is a back plate, 60 is a guide groove, 62 is a guide piece, 63 is a rotating piece, 80 is a first fixing roller, 81 is a second fixing roller, 83 is a fixed side plate, 86 is a movable side plate, 94
is an eccentric shaft, 95 is an operating lever, 104 is an impeller,
105 is an introduction cam, 108 is an introduction roller, 115
116 is a light emitter, and 116 is a photoreceptor.

Claims (1)

[Scope of Claims] 1. A charging device, an exposing device, a developing device, and a fixing device are provided in this order for charging, exposing, developing, and fixing an electrophotographic copying paper, and the fixing device includes a first fixing roller and a first fixing roller. a second fixing roller that is in pressure contact with the first fixing roller; the first fixing roller is rotatably supported on a fixed side plate;
The fixing roller is rotatably supported by the fixed side plate and rotatably supported by a movable side plate having an opening, and rotatably supported by the fixed side plate and engageable with the opening. An electrophotographic copying apparatus characterized in that, by rotation of an eccentric shaft provided, the eccentric shaft and the opening come into contact and the movable side plate moves to form a gap between both fixing rollers. 2. An introduction roller, an introduction roller arm that rotatably supports the introduction roller and is biased so as to press the introduction roller against the first fixing roller, and an introduction cam that comes into contact with the introduction roller arm. Claim 1, characterized in that the introduction cam is rotated in conjunction with the rotation of the eccentric shaft, and the introduction roller is pressed against the first fixing roller. Electrophotocopying equipment. 3. A speed increasing gear train connected to an eccentric shaft via a one-way clutch, and an impeller disposed at the final end of the speed increasing gear train, and the eccentric shaft reduces the gap between both fixing rollers. Claim 1 or 2 is characterized in that the impeller is configured to rotate in conjunction with the eccentric shaft via the one-way clutch only when the impeller rotates in the direction of rotation. Electrophotocopying equipment.