JP2518299Y2 - Paper feeder for electrophotographic printer - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a sheet feeding device for an electrophotographic printer that selectively uses cut sheets and continuous sheets.

2. Description of the Related Art Since electrophotographic printers are excellent in high-speed printing performance, they have been put to practical use in recent years as terminals for various computers. There are two types of printing paper for this electrophotographic printer: single-cut paper and continuous paper. In general, single-cut sheets are conveyed by rollers that hold them, and continuous sheets are conveyed by a tractor that engages pins with feed holes provided on the side of the sheet. An electrophotographic printer capable of printing is also provided with both a single-sheet paper transporting roller and a continuous paper transporting tractor as a paper feeding device. By the way, in a conventional electrophotographic printer capable of printing on both single-cut paper and continuous paper, tractors arranged before and after the printing position, that is, before and after the photosensitive drum (drum-shaped photoreceptor), Each of them is composed of a pair of left and right tractor feeders, and at least one of the tractor feeders is movable along its support shaft and is positioned according to the width size of the continuous paper used. Also, when switching from continuous paper to single-cut sheet and using it, if the tractor feeder is located inside the width of the single-cut sheet, set the movable tractor feeder of the tractor downstream from the photosensitive drum to the single-cut sheet. It was moved to a position where it would not interfere with transportation.

[Problems to be solved by the device]

As described above, the conventional apparatus has a problem that it takes time and effort to move the tractor behind the photosensitive drum every time the continuous paper having a width narrower than the cut sheet width is used. The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to switch papers without trouble in a paper feeding device of an electrophotographic printer that can selectively use cut papers and continuous papers.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, a sheet feeding device according to the present invention merges a single-sheet sheet carry-in path and a continuous sheet carry-in path in front of a photosensitive drum, and from the meeting point, between the photosensitive drum and a transfer device. In an electrophotographic printer that conveys paper along a common conveyance path from a fixing device to a discharge port, (a) a hopper for stacking cut-sheets in the carry-in path of the cut-sheets and the hopper (B) In the continuous paper carry-in path, fixed to a fixed position on one side in the paper width direction for carrying continuous paper into the common transport path. A first tractor comprising a fixed tractor feeder and a movable tractor feeder whose mounting position can be changed in the other side of the paper width direction, and (c) at the confluence, a single-cut sheet fed from the hopper. The common transport path (D) A fixed tractor fixed to a fixed position on one side in the paper width direction for carrying continuous paper to the common carrying path between the photosensitive drum and the fixing device. The second tractor including a feeder is provided. (E) A second roller and a third roller, which are arranged in front of and behind the second tractor, for transporting cut sheets, respectively.

[Action]

With the above configuration, when the continuous paper is used, the continuous paper is positioned on the first tractor and, after passing through the photosensitive drum, is fed to the fixed tractor feeder of the second tractor. When switching to single-cut paper after printing continuous paper and printing, the left and right feeders of the first tractor are continuous because the confluence of the single-paper input path and continuous paper input path is downstream of the first tractor. The position at which the paper is used may remain unchanged. In addition, since the second tractor is only the fixed tractor feeder on one side, there is nothing that interferes with the conveyance of cut sheets,
You can save the trouble of moving the second tractor.

【Example】

Next, an embodiment of the present invention will be described with reference to the drawings. In the housing 1, a charging device, an exposing device, a developing device, a transfer device 3, a cleaning device, and a fixing device 4 are arranged around the photosensitive drum 2 as basic components of the electrophotographic printer. For simplification, the charging device, the exposing device, the developing device, and the cleaning device, which are not directly related to the present invention, are not shown. Next, as a mechanism for transporting the paper, as a paper loading-related configuration, a hopper 6 for loading the single-cut paper 5 is loaded in and out of one side of the housing 1 and the continuous paper 7 is loaded in the same side of the housing. It has an insertion opening 8. Further, the paper transport path system has a single-cut paper carry-in path 9 connected to the leading end of the loaded hopper 6 and a continuous paper carry-in path 10 connected to the insertion port 8. Both of these carry-in paths are provided on the photosensitive drum 2.
Has a common conveyance path 11 which is continuous in front of the housing 1 and continues from the confluence to the discharge opening 12 opened on the other side of the housing 1 through the photosensitive drum 2 and the transfer device 3 and the fixing device 4. There is. A guide 13 is provided on each of the carry-in paths 9 and 10 and the common carrying path 11. As a cut sheet conveying means, a feeding roller 14 provided in the cut sheet carry-in path 9 for feeding the cut sheet 5 one by one from the loaded hopper 6, and a cut sheet provided at a confluence point of the carry-in path. First roller 15 for holding the slip paper and photosensitive drum 2
The second roller 16 and the third roller 17 are provided between the fixing device 4 and the fixing device 4 so as to be separated from each other in the front-rear direction. The first roller 15 is composed of a drive roller 15b fixed at a fixed position on the drive shaft 15a and a driven roller 15c which is in pressure contact with the drive roller 15b, and the second roller 16 is a drive roller 16b fixed at a fixed position on the drive shaft 16a. And a driven roller 16c that is in pressure contact with this, and the third roller 17 is composed of a drive roller 17b fixed in a fixed position on the drive shaft 17a and a driven roller 17c that is in pressure contact with this, and each roller 15, 16, 17 Driven rollers at 15c, 16c, 17c
When the continuous paper is processed, as shown in FIG. 5, as an example, the contact / separation means 15D, 16 including solenoids, links, and levers are used.
D and 17D separate the drive rollers 15b, 16b and 17b from each other. Between the drive shafts 16a, 17a of the second roller 16 and the third roller 17, a plurality of conveyor belts 18 are laid across the common conveyor path 11 in the width direction. In addition, as the continuous paper conveying means, the insertion port 8 and the carry-in path 9,
Between the confluence points of 10, that is, the first tractor 19 provided in the continuous paper carry-in path 10, the second roller 16 and the third roller 17
And a second tractor 20 provided between the two. The first tractor 19 is composed of two tractor feeders, that is, a fixed tractor feeder 19a and a movable tractor feeder 19b, which are separated in the paper width direction. The fixed tractor feeder 19a has a fixed position of the drive shaft 19c and the support shaft 19d, that is, for any of continuous papers having different paper widths.
The movable tractor feeder 19b is attached on one side of the conveyance reference line so as to be movable along the drive shaft 19c and the support shaft 19d. Further, the second tractor 20 is composed of one fixed tractor feeder 20a provided on the common transport reference line with the fixed tractor feeder 19a of the first tractor 19,
The drive shaft 20c and the support shaft 20d are mounted at fixed positions. Each of the tractor feeders 19a, 19b, 20a of the first tractor 19 and the second tractor 20 has a cover 19e, 1 for pressing a sheet, respectively.
9f and 20e are mounted, and there is a small gap between the tractor feeder and the cover so that sheets can pass through. The single-cut sheet transporting means 14 to 17 and the continuous sheet transporting means 19 and 2
A clutch 21 provided at one end of the drive shaft 15a of the first roller 15, as a configuration for applying a driving force to 0 and transmitting the conveying force to the sheet by each of these conveying means,
A gear 22 provided on the drive shaft 15a and connected to the driven side of the clutch, a gear 23 meshed with the gear, a pulley 24 fixed to the gear, and a drive shaft 16a for the second roller 16.
Transmission belt 26 laid between pulleys 25 fixed on top
And have. Further, the transmission belt 29 is stretched between the pulley 27 fixed to the other end of the drive shaft 16a of the second roller 16 and the pulley 28 fixed to one end of the drive shaft 20c of the second tractor 20,
A clutch 30 is provided on the drive shaft 20c of the second tractor, and further, a pulley 31 fixed on the other end of the drive shaft 20c of the second tractor and a drive shaft 19c of the first tractor 19 are fixed. A transmission belt 33 is wound around the pulley 32. A motor M capable of rotating in the forward and reverse directions is mounted on the shaft of the pulley 28. In this way, when the clutch 21 is turned on, the rotational force of the motor is transmitted to the drive shaft 15a of the first roller 15 and the drive shaft 16a of the second roller 16, and from the drive shaft 16a of the second roller 16 via the conveyor belt 18. Are transmitted to the drive shaft 17a of the third roller 17. Further, when the clutch 30 is turned on, the rotational force of the motor is transmitted to the drive shafts 19c, 20c of the first tractor 19 and the second tractor 20. Next, the operation when transporting continuous paper and single-cut paper based on the above configuration will be described. As shown in FIG. 2, in the sheet feeding device having the above-described configuration, when using a narrow continuous sheet 7A, for example, a 6-inch sheet, the movable tractor feeder 19 of the first tractor 19 is used.
Set b according to the continuous paper width. The loaded continuous paper 7A passes in the downstream direction along the carry-in path 10 and the guide 13 by the rotation of the tractors 19 and 20, that is, between the photosensitive drum 2 and the transfer device 3, and is transferred to the fixed tractor feeder 20a of the second tractor 20. Be guided. 3 shows a case where a wide continuous paper 7B, for example, a 15-inch paper is used in place of the narrow continuous paper 7A in FIG. 2, and the movable tractor feeder of the first tractor 19 is shown.
The state is shown in which 19b is moved away from the fixed tractor feeder 19a, that is, further moved rightward with respect to the conveying direction and set. Next, when switching from printing processing for continuous paper to printing processing for single-cut paper, continuous paper is detected by a continuous paper detector (not shown) provided between the confluence and the first tractor 19. When the motor is reversed,
After retracting the continuous paper until the continuous paper detector stops detecting, the clutch 30 is turned off, and the driven rollers 15c, 16c, 17c are pressed against the drive rollers 15b, 16b, 17b and the motor is rotated in the forward direction. Then, the feeding roller 14 is rotated by a predetermined amount. Continuous paper detector is OF from the beginning
In the case of F, the motor is immediately rotated forward and the clutch 3
The feeding roller 14 is rotated with 0 being OFF. In this way, the single-cut sheet 5 is fed out from the hopper 6 in FIG. 1, and the first-roller 15 provided at the confluence of the single-cut sheet carry-in path 9 and the continuous sheet carry-in path 10 conveys the single-cut sheet paper. 11 is fed to the second tractor 20 between the photosensitive drum 2 and the transfer device 3 and the second roller 16.
Is passed through the gap between the tractor feeder 20a and the cover 20e and guided to the third roller 17. Since the portion of the cut sheet other than the one end side is placed on the upper surface of the endless belt 18, the sheet can be conveyed by the plural endless belts 18 in addition to the second and third rollers 16 and 17. Therefore, the cut sheet is reliably transported. When the cut sheet paper 5 is conveyed through the common conveyance path 11, the other side of the second tractor 20 in the paper width direction does not have a tractor feeder unlike the conventional machine, so that regardless of the width size of the cut sheet paper, Transported smoothly. Therefore, switching from continuous paper to single-cut paper can be performed quickly without the need to manually move the tractor as in the conventional case.

[Effect of device]

As described above, according to the present invention, since the second tractor is composed of only one fixed tractor feeder, there is no need to move and adjust the second tractor according to the continuous paper width as in the conventional case. Also, it became possible to use continuous paper that is narrower than the width of single-cut sheets. Further, when switching from continuous paper to single-cut sheet, when the second tractor has a movable tractor feeder as in the conventional case, this movable tractor feeder must be moved to the outside of the single-cut sheet width. There is no sense. In addition, the number of parts is reduced, resulting in a low price.

[Brief description of drawings]

FIG. 1 is a schematic side view of an electrophotographic printer provided with an example of a paper feeding device according to the present invention, and FIG. 2 is a plan view showing a main part of the paper feeding portion of FIG. FIG. 3 shows a set state, FIG. 3 is a plan view showing a state in which wide continuous paper is set, FIG. 4 is a plan view showing a state in which cut sheet paper is set, and FIG. FIG. 3 is a perspective view showing the configuration of the power transmission system of FIG. 5 ... Single-cut paper, 6 ... Hopper, 7 ... Continuous paper, 9 ...
… Clip sheet carry-in route, 10 …… Continuous form carry-in route, 11 ……
Common transport path, 14 …… Feeding roller, 15 …… First roller,
16 …… Second roller, 17 …… Third roller, 18 …… Endless belt, 19 …… First tractor, 19a …… Fixed tractor feeder, 19b …… Movable tractor feeder, 20 …… Second tractor, 20a… … Fixed tractor feeder.

Continuation of front page (51) Int.Cl. ⁶ Identification number Internal reference number for FI Technical indication G03G 15/00 518 G03G 15/00 518 (56) Reference JP-A-63-251267 (JP, A) JP Flat 2-13527 (JP, A) JP-A-64-64874 (JP, A) Actually developed 61-47651 (JP, U)

Claims (1)

(57) [Scope of utility model registration request] 1. A conveyance path for single-cut sheets and a conveyance path for continuous sheets are merged in front of a photosensitive drum, and a common path from the junction to the discharge opening through the photosensitive drum and the transfer device and between the fixing device. In a paper feeding device of an electrophotographic printer that conveys paper along a conveyance path, (a) a hopper for loading cut papers in the entrance path for the cut papers, and one piece of the cut papers from the hopper (B) a fixed tractor feeder fixed to a fixed position on one side in the paper width direction for carrying the continuous paper into the common conveyance path, and A first tractor composed of a movable tractor feeder whose mounting position can be changed in the other side in the width direction, and (c) at the confluence point, for feeding the single-cut sheets fed from the hopper to the common conveyance path. The first roller of (D) A second tractor, which is a fixed tractor feeder fixed to a fixed position on one side in the paper width direction, for conveying continuous paper, to the common conveyance path between the photosensitive drum and the fixing device, (E) A second roller and a third roller, which are arranged in front of and behind the second tractor, for transporting cut sheets, and (f) spanned between the drive shafts of the second roller and the third roller. A paper feeding device for electrophotographic printers, each equipped with an endless belt that gives the paper conveyance power.