JPH047258A - Paper discharger for picture forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a paper discharging device for an image forming apparatus such as a copying machine or a printer that forms images using an electrophotographic method. This paper relates to a paper ejecting device that appropriately ejects paper to outside the machine after being separated from a container.

Conventional Technology This type of paper ejecting device is designed to make it easier to handle and dispose of jammed transfer sheets in the fixing section or subsequent paper ejecting path.
It is known from the publication No.-50908. The disclosed method is one in which a paper ejection path equipped with a pair of paper ejection rollers is simply retracted in an inverted manner from the operating position following the fixing device, or furthermore, this reversal and evacuation operation is supported by a parallel link type. This is done by the structure such that the distance between the paper ejection roller pair and the previous paper ejection guide and separation claw portion increases during the reversal and retraction operation.

Problems to be Solved by the Invention However, in any of the above-mentioned conventional paper ejection devices, the pivot shaft of the operating member that supports the paper ejection path in a reversible and retractable manner is provided near the bottom of the image forming block. For this reason, when the paper ejection path is reversed and retracted, the swing diameter is limited to within the height of the image forming block, so the swing diameter becomes small. It is still inconvenient.Also, if the swing diameter for reversing and retracting the paper ejection path is small, the posture of the paper ejection path changes rapidly during the reversing and retracting operation, so if the transfer sheet enters and is jammed, the paper ejection path When reversing and retracting the transfer sheet, the transfer sheet may be strained during the reversing and retracting operation.
I hate getting hurt. Furthermore, the separation claw on the paper ejection path side will also suddenly change its position and come into contact with and separate from the fixing roller, which may damage the fixing roller during this contact and separation.
There is also a problem in that the contact angle to the fixing roller becomes inconsistent. To solve this problem, it is conceivable to make the image forming block larger so that the pivot position of the operating member that supports it so that it can be reversed and retracted can be moved far away from the fixing device, but this is not preferable as it would lead to an increase in the size of the device. .

SUMMARY OF THE INVENTION Therefore, the present invention provides a sheet ejecting device for an image forming apparatus that can solve the above-mentioned conventional problems by improving the swing diameter of the reversing and retracting operation of the sheet ejecting path without increasing the size of the device. The challenge is to provide this information.

Means for Solving the Problems In order to achieve the above-mentioned problems, the present invention has a fixing device separating claw behind the fixing device of the image forming block, and a device that is inverted and retracted backward from the operating position following the fixing device. A paper discharging device of an image forming apparatus having a paper discharging path that is supported such that the paper discharging path is reversibly pivoted by a shaft located in a block lower than an image forming block. That is.

According to the above configuration of the present invention, the paper ejection path is located behind the fixing device of the image forming block in which the paper ejection path is provided, and the support member is pivotally supported by a shaft located in a block lower than the image forming block. Since the support member is supported by the support member, by rotating around the pivot position, the paper ejection path along with the separation claw is not limited to the size of the image forming block, that is, it is possible to With a swing diameter of such a large size, it is possible to invert and retract from the operating position following the fuser and return it to the operating position.

Embodiment Below, a paper ejecting device of an image forming apparatus as an embodiment of the present invention shown in FIGS. 1 and 2 will be described.

FIG. 1 shows a copying machine equipped with a paper discharge device according to the present invention. This copying machine has an exposure optical system 1, and an image is formed by exposure by the exposure optical system 1, and the image is transferred to a transfer sheet 2.
The image forming mechanism 3 includes an image forming mechanism 3 that transfers the image to the image forming mechanism 3, and a paper feeding mechanism 4 that feeds the transfer sheet 2 to the image forming mechanism 3. The exposure optical system 1, image forming mechanism 3, and paper feeding mechanism 4 are individually housed in independent optical system box 6, image forming box 7, and paper feeding box 8, respectively. The boxes 6 to 8 are stacked and connected to form a fuselage 9.

The exposure optical system 1 includes a lamp 13 that is supported by a first slider 12 that moves under a platen glass 11 to scan an original on the platen glass 11, a first mirror 14, a second slider 15, and a third slider 16. The second to fifth mirrors 17 to 20 move to keep the optical path length constant.
, a projection lens 21 provided between the third and fourth mirrors 18 and 190, and a sixth mirror 22 for correcting the optical path length during zooming by moving the projection lens 21 in the optical axis direction.

The image forming mechanism 3 includes a photosensitive drum 31, a charging charger 32 disposed around the photosensitive drum 31, a developing device 33, a transfer charger 34, a separation charger 135, and a cleaning device 136.
etc., and a photosensitive drum 31 using a known electrophotographic method.
A toner image corresponding to the original image to be exposed is formed thereon and transferred to the transferred transfer sheet 2. In front of the transfer section where the photosensitive drum 31 and the transfer charger 34 face each other, there is provided a paper feed conveyance path 35 for feeding the transfer sheet 2 received from the paper feed box 8 to the transfer section, and a timing roller is provided on the way. 36 are provided. The timing roller 36 is fed the transfer sheet 2 in a stopped state,
While the skew of the transfer sheet 2 is corrected by aligning the leading edge thereof, the timing of feeding the transfer sheet 2 to the transfer section is adjusted depending on the timing at which conveyance is started.

After the transfer unit, there is a conveyance device 37 that conveys the transferred transfer sheet 2 while adsorbing it to a belt, and a fixing device 38 that performs a fixing process on the transfer sheet 2 conveyed by the conveyance device 37.
, a paper discharge path 10 having a pair of paper discharge rollers 39 in two stages, front and rear, for discharging the transfer sheet 2 sent out from the fixing device 38;
1 is provided.

The paper feeding mechanism 4 has three paper feeding sections 41 to 43 that accommodate transfer sheets 2 of different sizes and selectively feed them. Each paper feed unit 41 to 43 has a paper feed cassette 44 to
Pickup roller 4 that sends out the transfer sheet 2 in 46
7 to 49, and a handling pad 51 for handling the transferred transfer sheets 2 one by one. Each paper feed section 41 to 43
Each of the blocks is divided into blocks, and the blocks can be exchanged by exchanging two blocks for one block for multiple sheets. Each paper feed section 41 to 43
The paper feeding power centers 44 to 46 are of a front loading type in which they are inserted and removed from the front side of the machine body 9, or from the front side of the page in FIG.

As shown in FIG. 2, the paper ejection path 101 further includes upper and lower sheet guides 102 in front of the previous paper ejection roller pair 39.
．． 103, and upper and lower sheet guides 104 and 105 are also provided at the two-stage paper ejection roller pair 39. A fixing device 38 is installed at the front end of the sheet guide 102, 103.
Separation claws 108 and 109 are positioned on the surfaces of the upper and lower fixing rollers 106 and 107 on the side from which the transfer sheet 2 is sent out, and are brought into contact with the biased force of a spring (not shown). The structure of these paper discharge paths 101 is a resin cover 111 that covers the outside of the machine body 9.
It is unitized into a sheet discharge section layer 112 provided in a part of the sheet.

For this unitization, a pair of left and right support side plates 113 are provided on the inner surface of the paper discharge section layer 112, and a paper discharge path 101 is provided on the support side plates 113.

The support side plate 113 has a lower roller 11 of the paper ejection roller pair 39.
4.115, lower sheet guide 103.105,
The child separation claw 109 is directly supported and forms a lower block 122 bordering on the paper passage path 121 of the paper discharge path 101.

On the other hand, the upper rollers 113 and 116 of the paper ejection roller pair 39
．． 117 , the upper sheet guides 102 and 104 , and the upper separating claw 108 form an upper block 123 bordering on the paper passage path 121 of the paper ejection path 101 . above block 1
23 is the rotating shaft 12 of the lower roller 115 of the lower block 122
The lower block 122 is supported by a movable plate 125 which is rotatably supported by the support side plate 113 so as to be rotatable about the lower block 122.

The paper discharge section layer 112 is pivoted by a pin 132 to a support frame 131 inserted into the paper feed box 8 from the image forming box 7, so that it can be opened and closed. The paper ejecting section layer 112 is opened and closed by rotation around this pivot point, and as described above, since the pivot point is located at a low position beyond the border of the paper feed box 8 below the image forming box 7, Without being affected by the height of the image box 7, the swing diameter of the reversing and retracting operation of the paper ejection path 1°l increases, and the paper ejection path 101
can be retracted from the operating position indicated by the solid line in FIG. 2 to the non-operating position, which is largely moved backward from the fixing device 38, as shown by the imaginary line in FIG. 2 to FIG. 3. As a result, the fuser 38
Since there is a large gap between the transfer sheet 2 and the paper ejection path 101, the jammed transfer sheet 2 is exposed to a large extent in the fixing layer 38 portion and the paper ejection path 101, making it easier to clear the jam.

Furthermore, if the pivot point of the paper ejection section layer 112 is low, the locus of movement of the paper ejection path 101 when retracting the paper ejection path 101 to the non-operating position as described above will draw a large circular arc due to a large swing diameter. Therefore, the jammed transfer sheet 2
has entered the paper ejection path 101, the paper ejection path 1
If the transfer sheet 01 has a small swing diameter and moves with a sharply curved trajectory with a sudden change in posture, the transfer sheet 2 may move away from the fixing device 38 while being squeezed.
As described above, when the movement locus of the paper ejection path 101 traces a large arc and the posture change is gradual, such a squeezing phenomenon can be reduced, and strain on the transfer sheet 2 can be avoided. can.

Also, the upper and lower separating claws 108 and 109 are the upper and lower fixing rollers 1.
06 and 107 in mutually different directions, but due to the locus of the large arc of the paper ejection path 101, the upper and lower fixing rollers 106 and 107 do not suddenly change their posture, and therefore do not force it. Therefore, damage to the fixing rollers 106, 107 can be avoided, and each separation claw 10B, 109 can be operated at an appropriate angle with respect to each fixing roller 106, 107.

When the paper ejection path 101 is retracted to the non-operating position as shown by the imaginary line in FIG. 2, by rotating the movable plate 125, the upper block 123 is moved counterclockwise from the lower block 122 as shown in FIG. The paper passage path 121 can be opened by pulling the sheet apart in the direction shown in FIG.

As a result, even if the transfer sheet 2 is jammed in the paper discharge path 101, it can be disposed of without difficulty by opening the paper passage 8121.

The closed state of the paper discharge section door 112 is maintained by a lock claw 141 provided at the upper end thereof being elastically engaged with the opening edge 111a of the cover 111 by the bias of a spring 142 as shown in FIG. To release this lock, press the lock claw 141 with the spring 1.
This can be done by rotating clockwise about the shaft 143 against the rotation angle 42.

The locking of the paper discharge section door 112 in the closed position by the lock claw 141 requires the pivot structure of the lock claw 141 and the
An elastic play is provided by the elastic deformation and pivot structure of 12, and when the paper discharge section door 112 is closed, the notch 144 formed in the support side plate 113 closes the image forming box 7.
As shown in the imaginary line in FIG. 3, the paper ejection path 10
1 and the fixing device 38 is accurately positioned.

On the other hand, the side plate 113 supports the upper back release claw 108 of the paper ejection path 101.
The shaft 147 pivotally supported by the stopper pin 146 and the notch 144 that engages with the stopper pin 146 are positioned on the movable plate 125 so that they are on the same axis. This allows for positioning of the notch 144 to engage with the stopper pin 146.
The pivot shaft 147 of the upper back release claw 108 and the stopper pin 146 are now located on the same axis, and the paper ejection path 10
1 and the notch 144 between the fixing device 38 and the stopper pin 14
6, the upper back release claw 108 can be properly operated at a precise position and angle relative to the upper fixing roller 106. Further, since the device release claw 109 is properly positioned on the support side plate 113, the device release claw 109 can similarly be properly operated on the lower fixing roller 107 by virtue of the positioning of the upper spine release claw 108.

Note that the present invention can be implemented in various modes other than those shown in the above-described embodiments, and the configuration of the paper ejection path and the method and structure of evacuation from the fixing device can be variously changed.

Effects of the Invention According to the present invention, the paper ejection path is located behind the fixing device of the image forming block in which the paper ejection path is provided, and is a support member pivotably supported by a shaft located in a block lower than the image forming block. By rotating the supporting member around the pivot position, the paper ejection path is not limited to the size of the image forming block together with the separating claw, in other words, it is possible to prevent the paper ejection path from being limited to the size of the image forming block. With the swing diameter, it is possible to invert and retreat from the operating position following the fuser and return to the operating position, so the paper ejection path can be evacuated from the operating position with a swing diameter large enough without increasing the size of the device. and can be returned to the operating position. Therefore, the paper ejection path is reversed greatly backward from the operating position, making it easier to clear the transfer sheet jam, and the posture change of the paper ejection path at that time becomes gentler, so that the transfer sheet is in a state where the transfer sheet enters the path. Even when the transfer sheet is reversed and retracted, it is possible to avoid squeezing the transfer sheet too tightly.

Similarly, the separation claw held in the paper ejection path can be easily moved toward and away from the fixing roller without any sudden changes in posture, so damage to the fixing roller can be avoided, and it is suitable for the fixing roller. contact can be made at any angle.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of a copying machine having a paper ejection device as an embodiment of the present invention, and FIGS. 2 and 3 are enlarged sectional views of main parts showing changes in the state of the paper ejection device. be. −・−1−−−−−−−・−Transfer sheet−・−−−−
−・−Image forming box・−・−・−−−m−Paper feed box−−−−−・・−m=−−・−・Constant loading device−・・
-1---------Paper ejection path, 109------
−One separation claw・−−−One paper ejection section door

Claims (1)

[Claims] (1) A paper ejecting device of an image forming apparatus having a separating claw for the fusing device behind the fusing device of the image forming block and a paper ejecting path that is supported so that it can be reversed and retracted backward from the operating position following the fusing device. A paper ejecting device for an image forming apparatus according to the aspect of the present invention, wherein a supporting member of a paper ejecting path is reversibly pivoted by a shaft located in a block lower than an image forming block.