JPH0361224A - Image forming device - Google Patents

Abstract

PURPOSE:To obviate operator's work of refilling papers by having a sheet-in- cassette presence detecting means control the operation of a drive means for a cassette through a sheet absence signal. CONSTITUTION:Sheets S in a cassette 3 is detected by a sheet presence detecting means A and through an undetected sheet signal the operation of a drive means 13 for the cassette 3 is controlled by a control means C. When there are no papers S in the cassette 3 during image forming, cassette S is automatically carried out of a device mainframe 2. As a result, operators can just refill papers in the cassette 3.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention relates to an image forming apparatus such as a copying machine or a printer, and more specifically to a cassette for loading sheets (hereinafter referred to as paper) used in the image forming apparatus. This invention relates to an automatic unloading mechanism.

(B) Prior Art Conventionally, paper cassettes used in copying machines, printers, and the like are capable of being inserted into and removed from the main body of the apparatus in order to replenish paper or change the paper size. In addition, there are two types of paper cassettes that can be attached and removed from the device body: one type that pulls out toward the side of the device body, and the other type that pulls out toward the front of the device body. thing.

2. When replenishing paper, it is possible to replenish paper without removing the cassette from the main body of the apparatus.

3. The cassette can be operated from the front, making it easy to handle.

For these reasons, the number of types in which the cassette is pulled out toward the front (hereinafter referred to as front loading) is increasing.

Furthermore, with front-loading type cassettes, the paper storage section inside the cassette must be brought out in front of the main body of the device, and in order to improve the poor operability of the cassette, which requires a long distance to move in and out. An autoloading device has been proposed in which a drive means is provided to automatically insert and pull out a cassette into a main body.

In the autoloading device, when the paper in the cassette runs out, it is detected and displayed at an appropriate location on the main body of the device.

(c) Problems to be Solved by the Invention However, in the copying machine with the above-mentioned autoloading device, when the paper runs out in the middle of copying multiple sheets, etc., a while after the machine stops, the display indicates that there is no paper. The paper replenishment in the cassette was also disadvantageous in that it was semi-automatic, in that the operator knew the condition and then pressed the eject key to eject the cassette and replenish the paper.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an image forming apparatus equipped with an autoloading device that can automatically unload the cassette from the main body of the apparatus when the paper in the cassette runs out during copying. It is something.

(d) Means for Solving the Problems The present invention has been made in view of the above-mentioned circumstances, and as shown in FIGS. 1 and 2, for example, a cassette (three ), a device body (2) that incorporates this cassette (3) and feeds paper, and the cassette (3).
), the image forming apparatus (1) has a driving means (13) provided in the apparatus main body (2) and for causing the cassette to be inserted into and removed from the apparatus main body (2). (3) sheet presence/absence detection means (A) for detecting the presence or absence of the sheet (S) in the cassette unloading control means (C) for controlling the operation of the driving means (13) based on a detection signal from the detection means; When the sheet presence/absence detection means (A) detects the absence of a sheet, the cassette unloading control means (C) moves the cassette (3) to the apparatus main body (
2), the driving means (13) is controlled so as to carry out the transport from.

(e) Function Based on the above configuration, the inner sheet (S) of the cassette (3) is detected by the sheet presence/absence detection means (A), and this sheet non-detection signal causes the driving means (1) of the cassette (3) to be detected.
3) is controlled by the control means (C), and if there is no paper (S) in the cassette (3) during image formation, the cassette (S) is automatically moved to the main body (2) of the apparatus. The operator only needs to replenish the paper into the cassette (3).

Note that the above-mentioned symbols in parentheses are shown for reference and do not limit the configuration of the present invention in any way.

(f) Examples Hereinafter, one embodiment of the present invention will be described based on the drawings.

As shown in FIGS. 1 and 2, the copying machine 1 has an apparatus main body 2.
It has a conveyance device 5 for automatically attaching and detaching the cassette 3 therein. A paper feed roller 6 consisting of a plurality of half-moon rollers disposed close to the upper side of the conveyance device 5 is fixed to a rotatable shaft 7 and feeds the paper S in the cassette 3 to the photosensitive drum 9. It is something. The toner image formed on the photosensitive drum 9 by a well-known means is transferred onto the fed paper S, and the paper S after this transfer is fixed by a fixing device (not shown) and then discharged from the machine.

As shown in FIG. 1, the conveying device 5 has a pair of parallel frames 11 and 12, and one frame 12 is provided with a motor 13 that can freely rotate in forward and reverse directions. . Gears 15, 16 are fixed to shafts 13a, which are connected to the output shaft of the motor 13 and pivotally supported by both frames 11, 12, respectively. A gear 19 meshing with the gear 15 is fixed to one end of a shaft 17 that is pivotally supported by the frame 12, and a sprocket 21 around which a chain 20 is wound is fixed to the other end of the shaft 17. ing. The chain 20 has a shaft 22
The chain 20 is wound around a sprocket 23 which is pivotally supported on the frame 12, and a drive pin 25 whose free end faces inward and a flag 2 for position detection are located at appropriate positions on the chain 20.
6 are provided respectively.

A photointerrupter sensor 27 is installed on the side of the frame 12.
. It is something. Frame 11.12
The rail 1 has a plurality of guide rollers 30 at the inner lower part of the rail 1.
1a.

12a, and one rail 12a is provided with a microswitch 31 that detects that the cassette 3 is inserted.

A gear 1 is attached to both ends of the shaft 33 which is pivotally supported by the other frame 11.
A gear 35 meshing with the sprocket 6 and a sprocket 36 similar to the sprocket 21 are respectively fixed, and a subrocket 37 connected to the sprocket 36 by a chain 38 is pivotally supported on the frame 11 by a shaft 39. ing. Further, the sprocket 37 is provided with a drive pin 25 that faces the drive pin 25 .

Grooves 40 in the shape of a cross in side view are formed on both sides of the front end of the cassette 3 to engage with the drive pin 25. When the drive pin 26 is in the front standby position as shown in FIG. When inserted into the conveying device 5, the drive pins 25 can enter through the openings 40c of the grooves 40, respectively.

As shown in FIG. 4, the apparatus main body 2 is provided with a paper presence/absence detection mechanism (sheet presence/absence detection means) A that detects the presence or absence of paper S in the cassette 3.

This paper presence/absence detection mechanism A consists of a detection lever 43 and a sensor 45, which are rotatably supported around a shaft 42, and when paper S is loaded in the cassette 3, the detection One end 43a of the lever 43 is placed on the upper surface of the paper S by its own weight, and the other end 43b is in a state where the optical path of the sensor 45 is blocked. The front end of the middle plate 46 on which the sheets S in the cassette 3 are placed is urged upward by a spring 47, and this urging force brings the sheets S into contact with the separator 49.

When the paper S in the set 3 runs out, one end 43a of the detection lever 43 falls into the notch 46a formed in the middle plate 46, and the detection lever 43 rotates counterclockwise in the figure around the shaft 42. do. Due to this rotation, the other end 43b of the detection lever 43 is retracted from the sensor 45 and turned OFF.
The control section C (see FIG. 6) of the main body 2 of the apparatus is informed that the paper S in the cassette 3 has run out.

The control section C includes the motor 1 as shown in FIG.
3, sensors 27 and 29, a microswitch 31, a sensor 45, an eject key 47 used when ejecting the cassette 3, etc. are connected to the cassette 3, respectively.

In the image forming apparatus configured as described above, when the cassette 3 is loaded with sheets S and installed in the main body 2 of the apparatus, the direction of entry of the opening 40a of the groove 40 of the cassette 3 (see FIG. 2) When the cassette 3 is inserted into the transport device 5 in this state, the drive pin 25 is inserted into the groove 40, and at the same time, the microswitch 31 is turned on by the bottom of the cassette 3. .

Upon receiving the ON signal from the microswitch 31, the control unit C drives the motor 13 to rotate the drive pin 25 together with the chain 20. As the drive pin 25 rotates, the drive pin 25 engages with one wall surface 40a of the groove 40, and as the drive pin 25 then moves linearly, the cassette 3 is moved in the direction of arrow E (see FIG. 2) and transported. It is inserted into the device 5.

When the cassette 3 is transported to the back standby position, the chain 2
The flag 26 with 0 is detected by the sensor 27, and upon receiving this detection signal, the control unit C stops the rotation of the motor 13, and thereby the cassette 3 is mounted at a predetermined position within the main body 2 of the apparatus.

When ejecting the cassette 3, the operator operates the eject key 47 shown in FIG. and rotate the drive pin 25 in the opposite direction. As the driving pin 25 reverses and moves in the opposite direction, the other wall surface 40b of the groove 40 is pressed by the driving pin 25, and the cassette 3 is moved in the direction of arrow Z in FIG.
When detected, the rotation of the motor 13 is stopped by a command from the control unit C. In this state, the cassette 3 is located at the front standby position, and the drive pin 25 is stopped in a state where the cassette 3 can be removed (see FIG. 1).

Next, the paper S in the cassette 3 installed in the device main body 2
If it runs out during copying, the detection lever 4 shown in FIG.
As described above, one end 43a of 3 is connected to the opening 4 of the middle plate 46.
6a and rotates counterclockwise in the figure, the sensor 45 outputs a signal ○FFL (no paper S, no sheet), and this signal indicating no paper S is sent to the control unit C.
is input. A series of controls for automatically unloading the cassette 3 based on the detection of the state of no paper S, and automatically loading the cassette 3 after replenishing the paper S by the operator will be explained using the control flowchart shown in FIG.

First, when the power is turned on by the operator, sensor 2
7 checks the current position of cassette 3 (S
101). In this case, the cassette 3 is attached to the main body 2 of the device, the drive pin 25 is at the back standby position, and the sensor 27 is ON, so the microswitch 31 is ON.
3102), and since this is ON, next check whether the copy key (indicated path) is pressed (S103). If the copy key is not pressed, press the eject key 47. By pushing, the motor 13 is driven in the direction (counter-arrow E direction) to carry out the cassette 3 outside the machine (outside the apparatus main body 2).

After the copy key is pressed and the copying operation starts, check whether there is paper S in the cassette 3 before making the next copy (5L21). If the paper S runs out, after confirming that the operation of the main unit 2 of the device has finished, remove the paper cassette 3.
The drive motor 13 is rotated in the ejection direction of the cassette 3 (S107). Next, check whether the sensor 29 is ON (5108). When the drive pin 25 moves to the front standby position, the sensor 29
is turned on, and the motor 13 is turned off (S109).

Next, check whether the microswitch 31 is turned on (5110), and if it is turned on, the same check is continued until it turns off. At this time, the operator
Confirm that the has stopped, replenish paper S, and load paper cassette 3.
After pulling out the cassette 3 until the microswitch 31 turns OFF, push the cassette 3 in again until the microswitch 31 turns ON. Then, it is checked that the microswitch 31 has changed from ON to OFF and then from OFF to ON (8110) (Sill), and the motor 13 is rotated in the direction of carrying in the cassette 3 (S113).

Next, check whether the sensor 27 is ON and the eject key 47 is OFF5114) (SIL5)
do. At this time, the sensor 27 detects that the cassette 3 is in the installed position (
If it has not moved to the back standby position), it is OFF, so next check whether the microswitch 31 is ON (
S116) This will not occur unless the operator removes the cassette 3 before the drive pin 25 engages with the cassette 3.
Since it is N, next check whether the sensor 27 is ON and the eject key 47 is ON (8117).
(8118), eject key 471; When tOFF is pressed, the process is repeated from (S114) to (S115).

In the meantime, cassette 3 moves to the mounting position and sensor 2
7 is ON, sensor 27 is ON and eject key 47
is off (Si14) (S115), the motor 13 is turned off (S119), and the cassette 3 is placed in the installed state. In the manner described above, the operator replenishes the paper S.

On the other hand, as shown in the control flowchart of FIG. 3, the cassette 3 is pushed into the apparatus body 2 and the microswitch 31 is turned on, regardless of whether or not the paper S has been replenished.
(S110.111), the cassette drive motor 13 is rotated in the cassette 3 loading direction (8
113). The subsequent operation is as described above, and during this time, the operation of the motor 13 is controlled independently of the signal from the paper S presence/absence detection means (paper presence/absence detection mechanism A) in the cassette 3.

By performing such control, when the paper S in the cassette 3 runs out and the paper S is carried out, if there is no paper S to replenish at hand, the cassette 3 can be left in the state in which it has been carried out. Once the cassette 3 is carried into the apparatus main body 2, the cassette 3 can be taken out using the eject key 47 and the sheets S can be replenished when necessary.

Although the above embodiment is an example in which the present front loading device is applied to a copying machine, it is not limited to this and can be applied to a printer,
It goes without saying that the present invention can be applied to other image forming apparatuses such as those for fusing, and furthermore, it can be applied not only to front loading apparatuses but also to other loading mechanisms.

(G) As described in detail, according to the present invention, the control means controls the operation of the cassette drive means based on the sheet non-detection signal from the sheet presence/absence detection means for detecting the presence or absence of sheets in the cassette. By providing this, the operator's effort in replenishing paper can be saved as much as possible, and the advantages of autoloading of the image forming apparatus can be fully utilized.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the essential parts of an image forming apparatus according to the present invention, FIG. 2 is a longitudinal cross-sectional side view of a copying machine (image forming apparatus) to which the present invention is applied, and FIG. A control flowchart showing one embodiment of the control of the autoloading mechanism of the image forming apparatus of the invention, FIG. 4 is a longitudinal sectional side view of the paper presence/absence detection mechanism section in the cassette, FIG. 5 is an operational view, and FIG. FIG. 3 is a block diagram of a control unit according to the invention. S... Sheet (paper) A... Paper presence/absence detection mechanism (sheet presence/absence detection means), C
... Control unit (cassette unloading control means) 2 ... Apparatus main body 3 ... Cassette 13 ... Motor (drive means) 9 ... Sensor 1 ... Micro switch

Claims (1)

[Scope of Claims] 1. A cassette for stacking sheets, a device main body incorporating the cassette and feeding paper, and a device that allows the cassette to be inserted into and removed from the device main body, and the device main body an image forming apparatus comprising: a sheet presence/absence detection means for detecting the presence or absence of a sheet in the cassette; and a sheet absence detection signal from the sheet presence/absence detection means to operate the drive means. and a control means for controlling cassette unloading, and when the sheet presence/absence detecting means detects the absence of a sheet, the cassette unloading control means controls the driving means to unload the cassette from the apparatus main body. An image forming apparatus characterized by: 2. The image forming apparatus according to claim 1, wherein the cassette unloading control means for operating the drive means controls the drive means to operate after the image forming operation of the image forming apparatus main body is completed. 3. The cassette unloading control means for activating the driving means responds to the sheet non-detection signal of the sheet presence/absence detection means in the cassette when the cassette is returned into the main body of the apparatus after activating the driving means. 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is controlled so that the carrying-out operation of the driving means is stopped regardless of the movement of the driving means.