JPH0241636Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a paper feeding mechanism for image forming apparatuses such as electronic copying machines and printers capable of automatic copying and manual copying.

(b) Prior art In order to reduce the external dimensions of the copying machine main body, the number of paper feed cassettes that can be detachably stored in the copy machine main body is limited to a small number, and copy paper other than the copy paper stored in this paper feed cassette is An electronic copying machine is in use that can easily make copies without having to replace the paper feed cassette. That is, this electronic copying machine takes out copy paper from a paper feed cassette by pressing a copy start switch attached to the copy machine body, transfers an original image onto the copy paper, and
This enables automatic copying, which fixes the original image, and manual copying, which similarly transfers and fixes the original image onto copy paper inserted through the window in the copying machine main body.

Conventional electronic copiers of this type (for example, Sanyo Electric Co., Ltd.)
The main parts of the electronic copying machine (SFT-850) are as shown in FIG. By pressing a copy start switch (not shown), only the topmost copy paper P is taken out by the paper feed roller 3 from the paper feed cassette 2 that has already been set in the copying machine main body 1, and this is taken out. The copy paper P is fed through a path 4 and register rollers 5 and 6 to just before the photosensitive drum 7, where it waits for the start of the transfer operation. Here, the register rollers 5 and 6 always try to apply a transporting force to the copy paper P;
It is prevented from slipping on the copy paper P by a stopper (not shown) that engages with the tip. This stopper is removed based on a transfer start command, and the register controllers 5 and 6 feed the copy paper P toward the photosensitive drum 7. These register rollers 5 and 6,
A sensor 8 provided on the side of the photosensitive drum 7 detects whether the copy paper P is in a state of waiting for the start of transfer. In addition to this paper feeding mechanism for automatic copying, copy paper is inserted from the window 9 of the copying machine main body 1 for manual copying.
A sensor 10 that detects the presence or absence of copy paper
It includes manual feed rollers 11 and 12 for transferring P' to the register rollers 5 and 6 side, and a passage 13. When this sensor 10 detects the introduction of copy paper P', it acts as a manual start switch for starting various mechanisms within the copying machine body 1, similar to the copy start switch described above.

In this conventional example, it is necessary to provide a sensor 10 and manual feed rollers 11 and 12 for manual copying, which not only has the disadvantage of increasing the number of parts, but also has the disadvantage of reducing the size of the copying machine itself. I was getting used to it.

(c) Purpose of the invention The present invention was created in view of the above points, and aims to provide a paper feeding mechanism for image forming devices such as electronic copying machines and printers that thoroughly reduces the number of parts and pursues miniaturization. It is something.

(d) Structure of the invention The invention consists of a first paper feed path that mechanically takes out the transfer paper in the paper feed cassette based on the main start command and transports it toward the register means, and a transfer paper feeder from the manual feeding window of the main body. a second paper feed path that receives the transfer paper and guides the transfer paper toward the register means, and a sensor disposed upstream of the register means,
The sensor has the role of notifying the presence or absence of the transfer paper at the register means position in response to the transfer paper passing through the first paper feed path, and the role of issuing a manual start command in response to the transfer paper passing through the second paper feed path. This is a paper feeding mechanism of an image forming apparatus configured to have the role of outputting.

(e) Embodiment FIG. 1 is a schematic diagram of the main parts of an electronic copying machine which is an embodiment of the apparatus of the present invention. In the same figure, 20
21 is a copying machine main body, 21 is a paper feed cassette that is configured to be freely retractable from the copying machine main body 20, and 22 is a copying machine main body;
23 and 24 are register rollers that control the transfer of the copy paper P to the photosensitive drum 25; 26 is the copy paper P; This is a guide path for transporting paper from the paper feed cassette 21 toward the register rollers 23 and 24. Also, 27
Reference numeral 28 denotes an opening for introducing manual copy paper P' into the copying machine main body 20, and a guide passage 28 for guiding the copy paper P' introduced from this opening 27 to register rollers 23 and 24. Both guide passages 26 and 28 join upstream of register rollers 23 and 24, and the copy sheets that have passed through register controllers 23 and 24 are treated in the same manner without distinction after this register controller. For convenience, the paper feed roller 22 and the guide path 26 are referred to as the first paper feed path, and one opening 27 is referred to as the first paper feed path.
The guide path 28 is referred to as a second paper feeder.

29 is a sensor located between the confluence of the guide passages 26 and 28 and the register rollers 23 and 24;
This sensor 29 has the same role as the conventional sensor 8 shown in FIG. 4 for copy paper P from the first paper feed path, and also for copy paper P from the second paper feed path.
In addition to the function of sensor 8, P' has the function of conventional sensor 10, that is, the role of a start switch during manual copying.

Reference numeral 25 denotes a photosensitive drum that is rotatably supported within the copying machine main body 20, and the original image formed on the photosensitive drum 25 is transferred onto copy paper P fed from register rollers 23 and 24. The image is transferred by a corotron 30 and fixed by a fixing device (not shown). Note that this photosensitive drum 25
As with a general electronic copying machine, there are a corotron for charging, an exposure device for forming a latent image, a developing device for developing the latent image, and toner for transfer leakage. Cleaning equipment is installed to remove the These act organically according to the program of the control mechanism to form a copy of the original on copy paper.

FIG. 2 shows a flowchart of the start process of the microcomputer 31 (see FIG. 3) attached to the device of the present invention. Before entering the routine shown in this flowchart, the microcomputer performs the initial settings of the microcomputer, the initial settings of the electrical components (motor, lamp, etc.), the jam removal, ), perform initial settings, etc. Then, when this copy preparation is complete, copy start instructions (input) are sent in this start processing routine.
wait for it to arrive.

If neither the command for auto copy nor the operation for manual copy is performed,
The loop of FIG. 2 is repeated until any operation is performed. When the start switch 32 for automatic copying is turned on, the loop moves from the loop to the exit loop, and the lever for pressing the copy paper P against the paper feed roller 22 starts feeding the paper from the paper feed cassette 21. (not shown) is turned on. After paper feeding starts, the copy paper P is at a predetermined position (sensor 29
Wait for the time (T seconds) until the sensor 2
Distinguish the signal of 9 (discrimination ○a). If the sensor 29 is on, the copy paper P is being fed normally, so the clutch 34 that turns on the register rollers 23 and 24 is turned on, the copy paper P is sent to the next process, and the copy process is started. to go into. If the sensor 29 is off, it is determined that the copy paper P has jammed in the first paper feed path or that there is no copy paper in the paper feed cassette 21, and the process proceeds to jam removal. When the sensor 29 turns on in the loop (judgment ○B), it goes to the route and goes to judgment ○B, but the sensor 29 is already on during manual copying, and there is no need for the time to pass from the paper feed cassette 21. Therefore, the register rollers 23 and 24 are immediately turned on to send the copy paper P' to the next portion and start the copying process. In this way, the sensor 29 is configured to function as a jam detection in the portion of judgment ○A, and to function as a start switch for manual copying in the portion of judgment ○B. The present invention is applicable not only to the electronic copying machine described above, but also to devices such as printers that connect paper (transfer paper) to image holding means such as a photoreceptor drum and form a transferred image on the paper. be.

(f) Effects of the invention The present invention provides an image forming apparatus in which automatic paper feeding mode and manual paper feeding mode can be selected, in which a sensor is disposed upstream of the register means, and this sensor detects the first paper feeding mode in automatic paper feeding mode. 1 paper feed path, and also functions as a start switch in manual feed mode, so it does not require a manual feed roller or It is practical because the sensor for the start switch can be omitted.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the main parts of an embodiment of the present invention;
FIG. 2 is a flowchart of a start process, FIG. 3 is a block diagram of a control system by a microcomputer, and FIG. 4 is a schematic diagram of a conventional device. Explanation of main symbols, 21...paper feed cassette, 23,
24...Register roller, 20...Copier main body, P,
P′...copy paper, 29...sensor.

Claims (1)

[Scope of utility model registration request] A first paper feed path for automatic paper feeding that mechanically takes out the transfer paper in the paper feed cassette based on the main start command and transports it toward the register means, and a first paper feed path for automatic paper feeding that receives the transfer paper from the manual feed window of the main body and transfers the paper. A second paper feed path for manual paper feeding that guides paper toward the register means, and a sensor disposed upstream of the register means, and the sensor is configured to guide the paper toward the register means when the paper is in the automatic paper feed mode. A paper feed mechanism of an image forming apparatus configured to detect a paper jam in a first paper feed path and operate as a manual feed start switch when in manual feed mode.