JPS5991468A - Electrophotographic copying machine - Google Patents

Abstract

PURPOSE:To obtain securely unfixing transfer paper not damaging an unfixing toner image by providing a switching means for moving an unfixing transfer paper discharging device and connecting the transportation path of transfer paper passing through a fixing device to the unfixing transfer paper discharging device side. CONSTITUTION:A microswitch 58 is operated on by a lever 52 to make a fixing device 45 to execute no fixing and move transfer paper 34 separated from a photosensitive drum 30 on a transportaion belt 44, and a microswitch 47 is operated to move the transportation belt 51a from the time point when the tip of the paper 34 reaches a discharge part 51. On the other hand, when the lever 52 is turned clockwise to a position for turning on the switch 58, a supporting member 54 is turned counterclockwise to space a discharge roll 48 and a discharge roll 49, the upper surface of the belt 51a of the discharge part 51 attains almost the same horizontal surface as the upper surface of the belt 44 to transport the unfix transfer paper 34b to the discharge part 51. A microswitch 57 is operated by the paper 34b, and to stop the belt 51a at the time point when the rear end of the paper 34b reaches the discharge part 51, and discharge the paper 34b so as a toner image does not contact with any part but is placed in horizontally.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic copying machine having a transfer paper fixing mode and an unfixing mode. 1゛′1! When copying an original T, For some reason, it is a very good match.

In other words, an unfixed copy in which the transferred toner image has not been properly exposed can easily erase ■ψ using a rubber band. After fixing in the two vessels, the desired copy can be easily obtained by performing the necessary IJl, Ibrush dC, and the above partially erased Original unfixed copy 11! By using this method, similar drawings, etc. can be created efficiently.

For this reason, f! Figures 1 and 2 are schematic diagrams illustrating this conventional copying machine.

In the figure, 1 is a photosensitive drum, 2> and 3ζ paper feeding rollers, 4 (miscellaneous paper feeding guide section, 5 is a belt surface charger, 6 is
7 is a static elimination charger, 7 is a suction belt, 8 is a suction fan, 9 is a heat guide plate, 10 and 11 are heating fixing rollers, 1
Reference numeral 2 designates an ejection tray for fixed transfer paper, and 13fd an ejection tray for unfixed transfer paper.

When obtaining a fixed copy, use the guide plate 9 as shown in FIG.
Make the upper surface 9a horizontal. Therefore, when the transfer paper 14 on which the toner image has been transferred is conveyed by the conveyor belt 7,
The transfer paper 14 is guided along the upper surface 9a of the guide plate 9.

As a result, the transfer paper 14 is fixed to the heat fixing rollers 10 and 1.
1, the toner image is fixed by being suppressed and heated, and then delivered to the discharge tray 12 in a JIF manner.

When obtaining an unfixed copy, the guide plate 9 is rotated counterclockwise by a predetermined angle as shown in FIG.

Therefore, the transfer paper 14 conveyed by the conveyor belt 7 is
The transfer paper 14 comes into contact with the surface 9b of the guide plate 9 and is guided by this surface 9b, thereby fixing the transfer paper 14 and immediately ejecting it to the ejection tray 13.

However, in such a copying machine CM, when obtaining an unfixed copy, the transfer paper 14 is
The toner image on the transfer paper 14 detours from the heating fixing roller 10°11, that is, the fixing device, and the toner image on the transfer paper 14 contacts the surface 9b of the guide plate 90 to form an image (
This may cause inconveniences such as streaks or partial disappearance (toner image).

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrophotographic copying machine that can reliably obtain unfixed copies without damaging the toner image. There is.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 3 is a schematic diagram 1 showing an embodiment of an electrophotographic copying machine (hereinafter simply referred to as a copying machine) CM according to the present invention. In the figure, 21 and 22d are transport rollers that transport the original 20, 23 is a contact glass, 24 is a backup plate, 25 and 26 are discharge rollers that eject the original 20, 27 and 28 are lamps that illuminate the original 20, and 2
Reference numeral 9 denotes a focusing light transmitting element array that forms a reflected light image from the original 20 on the photoreceptor drum 30; 31 refers to a photoreceptor drum; a charger that uniformly charges the surface; 32, a photoreceptor drum is formed on the surface thereof; A developing device that develops the electrostatic latent image with toner.
.

33 is a transfer paper tray, 34 is a transfer paper, 35 is a transfer paper 34
36 and 37 are separation rollers that separate and convey the transfer paper 34 one by one, and 38 and 39 are registration rollers.

40 is a transfer device that charges the transfer paper 34 and transfers the toner image on the surface of the photoreceptor drum; 41 is a separator that neutralizes the transfer paper 34 and separates it from the photoreceptor drum 30; 42 is the surface of the photoreceptor drum 30; The photoreceptor drum 30 is a cleaner for removing residual toner, and a static eliminator for removing residual charges on the surface of the photoreceptor drum 30.

44 is a conveyor belt that conveys the separated transfer paper 34; 45
46 is a suction fan that brings the transfer paper 34 into close contact with the conveyor belt 44; 47 is a microswitch; 48 and 49 are discharge rollers; 50 is a fixed transfer device; A discharge tray for accumulating paper 34, and 51 an unfixed transfer paper 34.
This is an unfixed transfer paper discharge section (hereinafter simply referred to as a discharge section) that discharges the unfixed transfer paper.

Details of this discharge section 51 are shown in FIG. In the figure, rollers 51b and 51 that drive the conveyor belt 51&
e, the respective shafts 51b' and 510 are attached to the side plate 51d.
The shaft 51b' is rotatably supported by the casing of the copying machine CM (not shown). Therefore, the transport bell) 51a and the rollers 51b, 51
The side plate 51d provided with the side plate 51d can rotate integrally around the shaft 51b'.

The lever 52 is pivotally supported by the housing via a shaft 52a fixed at one end thereof, and a connecting member 52b at the same end.
Further, a pin 53 is fixed to the connecting member 52b and fits into an elongated hole 51e formed in the side plate 51d.

At the other end of the support member 54 that pivotally supports the discharge roller 48 at one end, a bottle 54a that fits into the elongated hole 51e is fixed. It is pivotally supported by the f-damping body via the provided shaft 54b.

Further, inside the cover 55, there is a transfer paper 34 on the conveyor belt 51a.
A suction fan 56 (see FIG. 3) that brings the side plate 5 into close contact with the
1d is provided with a microswitch 57 for detecting the transfer paper 34, and a microswitch 58 that is actuated by a lever 52 and detects the position of the unfixed transfer paper discharge section 5. Upper M1. ': P'fE
located on the body.

FIG. 5 is a block diagram showing the t13 control device of the fixing tool 11 finisher 45. As shown in FIG. In the figure, 101 is a shift register for delaying the activation signal SI of the microswitch 47, 102, 111, 112, 114 and 119 are OR circuits, 103, 109 and 115 &
Flop, 104.107.

108.110.118 and 120 are AND circuits, 1
13 and 117 are inverters, and 116 is a differentiating circuit consisting of a diode, a capacitor, and a resistor.

In the above 41 cases, first, the operation when the toner image is not fixed on the transfer paper 34 will be explained. In this case, as shown in FIG. 4, the lever 52 is rotated in the 1 (7 o'clock) Nl-'Jj direction, so that the pin 53 slides to the left in the 1st hole 51e and moves against the side plate 51.d. IRI' is rotated in the R1 direction. Along with this, the bottle 54a force'J'7C, R
The support member 54 is rotated in the horizontal direction by sliding in the right direction within Le, and the discharge roller 48 is brought into contact with the discharge roller 49 (7) 1. Therefore, the discharge section 51 is moved in the direction shown in the 31st part 1 A- As shown in FIG. :L, the contact glass 23 and the bank up plate 2 are transported in the direction of the arrow by the transport rollers 21 and 22.
4 and is discharged to the right by discharge rollers 25 and 26.

When the original 20 is conveyed to the contact glass 23, its image is illuminated at
The reflected image is uniformly banded by the charger 31 through the convergent light transmitting array 29, and the photoreceptor drum 30, which is rotating in the direction of the arrow, is obtained. As a result, the original fA 2 is displayed on the table IIM of the photosensitive drum 3o.
The depth r1ζ of the image above 0 is shaped riQ.

This still image is developed with toner by the developing device 32. On the other hand, the transfer paper tray 33 is transferred to the pickup roller 35.
The photo paper 34 is conveyed in synchronization with the photosensitive drum 30 by registration rollers 38 and 39 so that its leading edge contacts the leading edge of the image on the photosensitive drum 30. The toner image on the surface of the photoreceptor drum is transferred by the transfer device 40. Then, the separator 4
1, the transfer material 34r to i (+gekiyo belt 44 is used to convey the transfer material to Jingfu/↓To1N45).

During this conveyance, the transfer paper 34 turns on the microswitch 47. Therefore, the microswitch 47 is opened when the transfer paper 34 is passing over it, and as shown in FIG.
a) Add a signal Sf as shown in K to the shift register 101.

The shift register 101 outputs the signals delayed by the time L1+j! and t3 from the output terminals Qm, Qn, and Qi, respectively ((b) in the same figure).
, (c) and (d)).

This delay time t1 is a delay in the time required for the shift register 1o1 to perform m shift operations, that is, the time required for the transfer paper 34 to move from the first shift of the microswitch 47 to the transfer paper entrance of the fixing device 45. The time t2 is the time required for the shift register 101 to shift n times, that is, the transfer paper 34 is transferred to the microswitch 47.
The time required to move from the 0th position 1be to the transfer paper exit of the fixing device 45, and the delay time t8, is the time required for the shift register 101 to perform i-times shifted b operation,
That is, each time is set to the time required for the transfer paper 34 to move from the position of the microswitch 47 to the discharge tray 50 (or the stain discharge section 51). In addition, m (n
(It is i.

L7 Therefore, the output signal of the OR circuit 102 is as shown in the same figure (e
), the leading edge of the transfer paper 34 is connected to the fixing device 1'i".
The logic level is "H" from the time when the rear end enters the 45 until the time when the rear end is discharged -Mt+-.

Then, the clock signal PC immediately after the output signal of the OR circuit 102 of
The state of 03 changes and its output terminal Q becomes the logic level rHJ.
(See figure (f)). At the same time, the output terminal 4 of the flip-ruff 0 frog 103 falls to logic 1/bell rLJ, so the AND circuit 120 is rendered inactive, and the state of the flip-flop 103 is thereby maintained.

Also, since the counter 105 is enabled while the output terminal Q of the free-ruff 0 frog 103 is at the logic level r II J, the counter 105 is clocked fa
The PC number t is counted up, and the count value of the counter 106 is incremented every time there is a carry (overflow). Then, when nEi" of this counter 106 reaches the intermediate value after a predetermined time T'+, the same 1tl (g)
As shown in FIG.
I (J. Therefore, the output of the AND circuit 110 becomes the logic level rHJ in synchronization with the clock signal PC as shown in C1 in the same figure, and thereby the flip-flop 103 and the counters 105 and 106 are reset. Ru.

Due to the clock signal PC generated immediately after this, the state of the frill rough 0 flop 103 changes to f'■IJ'j''l-:
, and the logic level of its output Cfft1Q is r $I
Stand up to J. .

Therefore, the output 1'r of the flip-flop 10:4
;:Logic level tj1 of 11Q, output of main circuit 102; logic 1/bell r HJ tj:While i
l+1li-f] Tl1- After becoming HJ, the state Z) is repeated in one clock period rLJ.

This flip clip 103 GL) output jI: (5Q
(The signal is passed through the AND circuit 104,
11 is output to the fixing device 45 as a signal SC, thereby charging a capacitor for flash lamp emission of the fixing device 45. Therefore, the time T+&J is set as the time required to accumulate a predetermined charge in this capacitor. In addition, the output of the AND circuit 110 is applied to the OR circuit 111''&21 constant *:i device 45, and the flash lamp trigger acts as (,?) ST.

In this way, each time the transfer paper 34 advances a predetermined distance after entering the transfer paper 34, the flash rung emits light and the toner image on the transfer paper is heated and fixed.

Note that this action ends when the output of the OR circuit 102 becomes the logic level "L", that is, when the trailing edge of the transfer paper 34 is also ejected from the fixing device 45.

Then, this fixed transfer paper 34a is transferred to the discharge roller 4.
8 and 49, the paper is discharged onto the discharge tray 50.

Next, the operation of this embodiment when the transfer paper is discharged in an unfixed state will be explained.

In this case, as shown in FIG. 7, the lever 52 is rotated clockwise to 1iffi, which turns on the microswitch 58. At the time of O, the bottle 53 slides the elongated hole 51e to the right! RII L, and side plate 51. d Rotate clockwise. Accordingly, the pin 54g slides to the left inside the elongated hole 51e, the support member 54 rotates counterclockwise, and the discharge roller 48 is separated from the discharge roller 49. In addition, in the illustrated state, the discharge portion 51 comes into contact with an engaging member (not shown), and this state is maintained.

Therefore, as shown in FIG. 8, it is determined that the upper surface of the conveyor belt 51a of the discharge section 51 is located approximately on the same horizontal plane K (it) as the upper surface of the stacking belt 44,
Moreover, the discharge roller 48 is separated from the discharge roller 49.

As mentioned above, since the microswitch 58 is turned on by the lever 52, the microswitch 58 activation signal St&:J1, j'lT9 (e
), the logic level is rHJ. This signal S is applied to the fixing device 45 as the fixing operation prohibition signal SD via the OR circuit 114, and when the logic level of this signal SD is "H", the signal S is applied to the fixing device 45 as the above-mentioned signal sc and Even if ST is applied, the fixing device (i'j, 4.5 tJ: does not perform the fixing operation. Also, the signal s2 acts as a control signal for the suction fan 56, and therefore the suction fan 56 does not operate the lever 52. Its operation begins when it is rotated to the position shown in FIG.

When the transfer paper 34 separated from the photoreceptor drum 30 moves on the hub belt 44, the microswitch 47 is activated in the same manner as described above, and an activation signal S1 as shown in FIG. 9(a) is output. be done. Then, as shown in FIG. 3(b), shift register 1 is delayed by time t3 from this signal SI.
When the output terminal Qi of 01 rises to the logic level rHJ,
The state of the flip-flop 115 changes and its output signal SM becomes a logic level rHJ (see (f) in the same figure),
At the same time, the output of the differentiating circuit 116 becomes the logic level rHJ (see (c) in the figure).

The signal SM is output from the roller 51b of the discharge section 51.

51c and the drive source of this roller, and therefore, when the signal SM reaches the logic level rHJ, that is, the leading edge of the transfer paper 34 reaches the discharge section. 51, the conveyor belt 51a is activated, and the unfixed transfer paper 34b is thereby conveyed to the discharge section 51 by the conveyor belt 51a.

The microswitch 57 is actuated by the transfer paper 34b conveyed by the discharge section 51, and as shown in Figure 9, the actuation signal S rises to the logic level rIIJ&ζ, and the AND circuit 118 becomes operable. 7; becomes Jl.

Then, when the rear end of the transfer paper 34b reaches the ejection rflI 51, the logic level of the output terminal Qi of the shift register 101 falls to rLJ, and the falling edge of and is differentiated by the differentiating circuit 116, and this differential The output of the circuit 116 is converted into a nof pulse signal PS by an inverter 117 (
Figure 9(d) Reference 11@). This pulse signal PS resets the 7 reset logic flag 115 via the AND circuit 118 and the OR circuit 119, whereby the logic level of the signal SM falls to "7" and the transport bell 51a stops. 1 In this way, from the time when the leading edge of the transfer paper 34b (51Ri, L) reaches the discharge section 51, the opening operation is performed until the rear end of the transfer paper 34b gets on the discharge section 51, and as a result, the transfer paper 34b is conveyed onto the discharge section 51 and held under suction.

In FIG. 5, signals R8 and JM are a reset number 1d and a paper jam occurrence signal, respectively, which are output from a copy control section (not shown). This signal R8
is added, shift register 101, flip-flop 103, counters 105 and 106, and flip 70
7'109 and flip-flop 115 are reset.

Further, this signal R8 is outputted to the flash lamp as a trigger signal ST via the OR circuit 111, thereby resetting the capacitor that drives the flash lamp.

The signal JM is output to the flag lamp as a trigger signal ST via the OR circuit 111, and is also output to the OR circuit 1.
14 as a fixing operation prohibition signal SD to the fixing device, the capacitor is reset, and the fixing operation of the fixing device i17 is prohibited.As explained above, in this embodiment, the toner image is The transfer paper to which the image is fixed can be separated from the transfer paper to which the image is not fixed. In addition, since the toner image formed on the unfixed transfer paper is ejected into a groove placed horizontally without touching anywhere, the toner image is not damaged. do not have.

In addition, if the above-mentioned signal Ssk copy control (,'l'l1) is added as a copy prohibition signal, 4) "out" ~
Since the next copying operation is not performed unless the unfixed copy discharged to the 1X51 is removed, it is possible to prevent the inconvenience of damaging the toner image by overlapping another transfer sheet on top of the unfixed transfer sheet. This is especially effective when the present invention is implemented in a copying machine having a repeat function.

In the above embodiment, a flash lamp type fixing device is used as the fixing device, but the fixing device is not limited to this.
3. For example, the same method can be implemented even when the heating roller type fixing device 1Y is used. However, in that case, appropriate transfer paper conveyance means should be provided before and after the heat fixing roller (or on either side of the roller), and the activation signal S of the microswitch 58 should be provided.
2 or in conjunction with the discharge section 51! It is necessary to insert a heat shield material between the separated roller and the conveyance path of the transfer paper.

Note that the movement of the lever 52 that operates the ejection part 51 (・I
It is also possible to use a motor operated by a switch that selects manual or unfixed mode.

As described above in the explanation I-, according to the present invention, the fixing device 1''
! Transfer the unfixed transfer paper to 1 without taking a detour from 1.
The unfixed toner f'
Since the transfer paper can be twisted and conveyed without coming into contact with anything and the transfer paper is kept flat, it has the effect that unfixed paper can be reliably obtained without being damaged.

[Brief explanation of drawings]

1 and 2 show a conventional copying machine. ! T
FIG. 3 is a schematic diagram showing the operation mode of an embodiment of the present invention when obtaining a fixed transfer paper, and FIG. 4 shows a discharge section for unfixed transfer paper when obtaining a fixed transfer paper. FIG. 5 is a block diagram showing a control device in an embodiment of the present invention, and FIGS. 6 (-) to (1) show the fixing operation of the device shown in FIG. The waveform diagram shown in FIG. 7 shows the operation state when obtaining a fixed transfer paper. The general e・H<I゛7+, ph s diagram showing the Ni1l mode is a schematic diagram showing the operating mode of a single blood example of the present invention when obtaining unfixed transfer paper, and FIG. ) to (FZ) are waveform diagrams showing the operating state of the apparatus shown in FIG. 5 in 1 when printing unfixed transfer paper. 50... Ejection tray, 51... Ejection section, 52...
Lever, 58...micro switch. Representative Patent Attorney Crest 1) Makoto

Claims (1)

[Claims] A mode in which the transferred toner image formed on the transfer paper is fixed and discharged, and an unfixed i! It also has a discharge mode. In the electrophotographic copying machine, a transfer paper discharging device for discharging fixed transfer paper and an unfixed transfer paper discharging device for discharging unfixed transfer paper are provided on the downstream side of a fixing station in a transfer paper transport path, and By moving the unfixed transfer paper ejecting device f4, the fixing device value is changed (Qj), and the conveyance path of the passed transfer paper is connected to the transfer paper ejecting device side or the unfixed transfer paper ejecting device side. Do!, 7I conversion means, electronic photo r and J photo iso.