JPH11147618A - Paper feeder of large capacity - Google Patents

Abstract

PROBLEM TO BE SOLVED: To horizontally vertically move paper, also so that constitution of a lift mechanism of a tray can be simplified, in the large capacity tray mounted in a paper feed part of an image recorder. SOLUTION: In a large capacity tray 30 arranged in a paper feed part of an image recorder, a support plate 31 supporting paper is supported by using a link mechanism 33 combining four links, to be driven by a drive screw shaft 37 of a drive unit. A lower surface of the support plate 31 and a bottom plate of the tray are fixed to a pad 35, 35a, a slide member 34, 34a arranged in both sides is moved in a direction mutually separating coming into contact by a screw of the drive screw shaft 37, the paper is vertically moved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large-capacity tray disposed in a paper feeding section of an image recording apparatus, and more particularly, to a large-capacity tray configured to simplify a mechanism for lifting paper accommodated in the large-capacity paper feeding tray. .

[0002]

2. Description of the Related Art Generally, a paper feeder provided in an image forming apparatus such as a copying machine, a printer, a facsimile machine, etc.
A paper feed tray capable of storing about 50 to 500 sheets is provided, and a lifting mechanism such as a spring is used to press the paper stored in the paper feed tray toward a paper feed roller or the like. However, in the image forming apparatus, the amount of used paper increases as the number of copies made per unit time increases, and in order to reduce the number of times of replenishing the paper, and when the office is closed. In order to be able to receive the same, a large-capacity paper tray is often provided. For example, the large-capacity paper tray is configured to be capable of storing 1000 to 2000 sheets of paper. However, when the large amount of paper is fully stored, the weight of the paper is about several kg. To become
Spring biasing means cannot be used. Therefore, in the large-capacity tray, the support plate for supporting the paper is suspended and supported by a plurality of wires, and the wire is driven by using a winding unit to move the paper to a predetermined position of the paper feeding unit. It uses a mechanism to raise it.

[0003]

However, in an apparatus for supporting the support plate by using an elevator mechanism, a pulse motor or the like is used to wind up a wire, and a few mm is used.
It is necessary to carry out the operation of raising the paper by each. And
The use of such a motor and the provision of a wire and a guide mechanism for the lift device in order to provide a control unit for driving the motor complicate the configuration of the device, and at the time of maintenance, There is a problem that a lot of trouble is required.

The present invention solves the above-mentioned problem of the conventional large-capacity tray, and employs a lifting device using a means for vertically moving a support plate on which sheets are placed using a link mechanism and a screw shaft. It is an object of the present invention to provide a large-capacity tray capable of simplifying the configuration of the above.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a large-capacity tray disposed in a paper feeding section of an image recording apparatus. According to a first aspect of the present invention, a supporting plate on which a sheet is placed is horizontally supported by a lifting device, and the lifting device is configured by a link mechanism in which a plurality of links are connected via pins. The horizontal screw shaft is rotated to be deformed, and the support plate is moved up and down. The invention according to claim 2 is characterized in that the lift device is configured as a pantograph-shaped link mechanism in which four links are pin-connected in a rhombus shape, and upper and lower opposing pin connection portions are attached to a support plate and a base of a tray, respectively. A slide member provided at the left and right pin coupling portions of the link mechanism is driven in a direction in which the slide member is separated from and brought into contact with a screw shaft. The invention according to claim 3 is characterized in that the lift device is constituted by an X-shaped link mechanism in which a center portion of two links is connected by a pin, and a slide member disposed at a lower end portion of the two links of the link mechanism is a screw shaft. And driving the support plate disposed at the upper ends of the two links to slide under the support plate, and vertically moving the support plate supporting the paper horizontally. Features.

[0006] With the above-described structure, the lift device arranged on the support plate is configured using the link mechanism and the screw shaft. Therefore, the mechanism of the lift device arranged on the large-capacity tray can be simplified. can do. Further, even when the number of sheets stored is very large, the operation of lifting the sheet using the lift device can be accurately performed, and the maintenance of the large capacity tray can be easily performed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A large capacity tray according to the present invention will be described with reference to the illustrated example. Image recording device 1 shown in FIG.
1 shows a configuration in which a facsimile reading device 20 used for a facsimile device is combined with an upper portion of a main body of a device that creates a recording sheet using an electrophotographic method. The paper feeding unit disposed below the image recording apparatus 1 includes:
A large-capacity tray and a paper feed roller 3 for taking out the paper are arranged, and the paper taken out by the paper feed roller 3 is sent out to the image forming section by a transport roller device 6 via a paper transport path 5. . Further, a gate 6a is disposed in the portion of the transport roller device 6, and the gate 6a is opened in timing with a toner image to be formed on the photosensitive drum, and a sheet is sent out by the transport roller device 6, and an image is formed. To perform the transcription action. The image forming unit 10
The developing unit 11 and the photosensitive unit 15 are provided in combination, and an LED head 17 for writing an image on the photosensitive drum 16 is disposed.

In the developing unit 11 and the photosensitive unit 15 arranged in the image forming section 10 of the image recording apparatus, the developing unit 11 and the photosensitive unit 15 are provided inside the developing unit 11 similarly to a general electrophotographic image forming apparatus. Stir the toner,
Means for supplying the toner to the developing roller 12, means for charging the toner, and the like are provided. Also, the photosensitive drum 16
Although a mechanism such as a charging unit is also arranged, in the description of the present invention, the charging unit and the toner conveying unit can be configured in the same manner as a general electrophotographic system. A description of the configuration and operation of each component disposed in 10 is omitted.

In the image recording apparatus, the photosensitive drum 16 is irradiated with light of image information from the LED 17 to form an electrostatic latent image on the photosensitive drum which is uniformly charged in advance. For the electrostatic latent image,
The toner is supplied from the developing roller 12 to form a toner image, and the transfer roller 18 transfers the toner image to the sheet by the action of applying a potential from the back side of the sheet. The sheet on which the toner image has been transferred is fixed through a fixing device 7 and sent out to a discharge tray 9 by a discharge roller 8.

In the example shown in FIG. 1, the image recording apparatus is combined with a reading mechanism of a facsimile apparatus to form an image recording apparatus 1 as an apparatus having a composite function. In the image recording apparatus 1, a facsimile reading device 20 disposed at an upper portion of the apparatus main body reads an image of a document set on a document tray 21 based on an operation command input to a control device 19 provided in the apparatus main body. , The image information is transmitted using a facsimile function. The facsimile reader 20
A pickup roller 22 for taking out a document from a document tray 21 and a sheet separating device 23 are arranged, and while the document is transported by a transport roller device 24 along a document transport path formed in a substantially U-shape, a reading unit is provided. To read the image.
A platen glass 27 is disposed in the reading unit, as in the case of a general facsimile machine, and a lamp 2
8 and a CCD 29 are provided. Then, light from the lamp 28 is irradiated on the original, and the reflected light is converted into an electric signal by the CCD 29 and transmitted via a communication line.
The image information obtained from the CD can be transmitted to the LED of the image forming unit to create a recording sheet.

In the document feeder disposed in the facsimile reading device 20, the sheet separating device 23 is configured by combining a feed roller and a retard roller, and separates the documents one by one and sends them out to the reading unit. As the transport roller device, a plurality of pressing roller members are arranged for a large-diameter drive roller also serving as a guide portion inside a curved portion of a U-shaped document transport path, and a plurality of pressing roller members are arranged at the curved portion of the document. Is configured to be guided. A discharge roller device 25 is disposed at the discharge side end of the document conveying path, and discharges the read document toward the discharge tray 26.

FIGS. 2 and 3 show a configuration of a large capacity tray 30 arranged in a paper feeding section of the image recording apparatus. FIG. Indicates that the paper has run out. In this embodiment,
A support plate 31 for placing paper inside the large capacity tray is supported by using a lift device 32,
The lift device 32 is configured as a diamond-shaped link mechanism 33 by connecting the ends of four links L1 to L4 with pins as shown in FIG. In the link mechanism 33, the upper pad 35 arranged at the upper connection portion is attached to the center of the support plate 31, and the lower pad 35a arranged at the lower connection portion is fixed to the lower portion of the tray. In addition, slide members 34 and 34a are disposed at connection portions on both sides of the link mechanism 33, and the slide member is provided on a drive screw shaft 37 configured as a screw shaft in a direction opposite to a center portion as a boundary. A nut portion corresponding to the screw is provided. A motor 38 and a gear transmission mechanism 39 are disposed in the drive unit 36, and the gear provided at the end of the drive screw shaft 37 is engaged with the gear at the end of the gear transmission mechanism 39, and the drive screw shaft 37 is moved in the forward and reverse directions. Can be rotated arbitrarily.

In the link mechanism 33, the screw of the drive screw shaft 37 is meshed with the screw portion provided on the slide members 34 and 34a arranged on both sides. , The two slide members 34 and 34a are moved in a direction in which they are separated from each other. Then, when the paper is lifted, by rotating the drive screw shaft 37 to one side and moving the slide members toward each other, the support plate 31 can be raised as shown in FIG. When the paper is lowered, the drive screw shaft is driven in the reverse direction, so that the link mechanism 33 is moved as shown in FIG.
Is moved in the direction in which is crushed. The drive unit 36 for vertically moving the support plate 31 includes a motor and a gear transmission mechanism 39 as one unit, and is disposed at an end of a drive screw shaft 37 so that the unit is integrally formed with the drive screw. By being configured to be movable in the vertical direction together with the shaft, as shown in FIGS. 2 and 3, the support plate is moved in the vertical direction following the vertical movement of the support plate.

A paper feed roller 3 swingably supported by a link 3a is arranged in a paper feed section of the large capacity tray 30, and the paper taken out by the paper feed roller 3 is transported through a paper transport path 5. Paper is fed toward the roller device 6. In the paper feed roller 3, a roller is provided so as to be able to be separated from and brought into contact with the paper by a link 3a, and the roller 3 is pressed against the paper only when a paper feeding operation is performed. As the mechanism, a conventionally known means such as a drive mechanism combining a solenoid and a spring can be used.

At the upper part of the large capacity tray, sensors S1 and S2 are arranged for defining the rising position of the sheet P and for detecting the presence or absence of the sheet in the tray. In the present embodiment, the sensor S1 is a paperless sensor,
2 is used for detecting the rising position of the sheet, and the sensor S
Reference numeral 1 denotes a state in which a hole is formed in the support plate 31, and in the state where there is no paper on the support plate, the arm of the sensor enters the hole of the support plate and swings greatly to detect the no paper state. . The sensor S2 is used to detect the rising position of the paper placed on the support plate. For example, when the lift device 32 is driven to lift the paper, the sensor S2 detects ,
The paper is raised by a few mm and set so that the paper can be sent out by the paper feed roller.

During the operation of preparing the recording paper (feeding operation from the paper feed tray), the position of the upper end of the paper is lowered, and the sensor S2 does not detect the paper. At times, the control device drives the drive unit of the lift device by the signal of the sensor, and starts the operation of raising the support plate. Then, during the operation of raising the support plate, after the sensor S2 detects the sheet,
The control is performed such that the sheet is lifted by a few millimeters to stop the rising of the sheet. When all the paper in the paper feed tray is fed, the sensor S1 outputs a no-paper signal. When the signal is output, the control panel of the image recording apparatus displays the no-paper signal. (Sheet replenishment command) and the operation of driving the motor of the drive unit in the reverse direction to lower the support plate 31 to the lower limit position is performed so that the large capacity tray can be pulled out from the apparatus main body. Also, when replenishing paper while a small number of papers remain in the large capacity tray, operate the handle for pulling out the tray or input any other operation signal to the control device. Thereby, the operation of automatically lowering the support plate can be performed.

The example shown in FIGS. 4 and 5 shows another configuration of the large capacity tray. A lift device 42 for moving the support plate 41 of the large capacity tray 40 up and down is provided with an X-type link mechanism. 43. The link mechanism 43 includes two links L1 and L2 at the center pin 43.
The links are connected by a to form an X-shape. Slide members 44 and 44a are provided below the link, and the slide members are provided with screw portions corresponding to the screws of the drive screw shaft 47. Further, supporting members 45, 45 are provided at the upper end of the link.
The support member is slidably provided on the lower surface of the support plate 41 so that the support member 41 is moved up and down while the horizontal state of the support plate 41 is maintained. In the drive unit 46 provided on the large capacity tray 40, a motor 48
And the gear transmission mechanism 49 is combined to drive the gear at the end of the drive screw shaft 47. The drive screw shaft 47 is provided with a screw in the opposite direction with respect to the center part, and by rotating the drive screw shaft in the forward and reverse directions, the slide member 4
The support plate 41 supporting the link mechanism 43 is moved up and down by moving the base plates 4 and 44a in a direction in which they are separated from each other.

One sensor S is disposed above the large-capacity tray to detect the rising position of the sheet and the detection of no paper. Then, when there is a sheet on the support plate 41, the sensor S detects the rising of the sheet, and after the arm of the sensor detects the sheet, the support plate is further raised by a predetermined height. , Corresponding to the feeding operation by the half-moon roller 4. In the state in which a predetermined number of sheets have been fed out during the sheet feeding, the sensor cannot detect the upper part of the sheet, and in that case, a driving signal to the driving device is output by a signal from the sensor. Then, the support plate is raised to a certain height so that the sheet feeding operation can be continued. Further, when the paper runs out, the arm of the sensor S falls into the hole provided in the support plate, and it is detected that the arm swings greatly, so that a no-paper signal can be output. As described above, in this embodiment, the sheet detecting operation can be performed by providing a means for outputting two types of detection signals to one sensor. Also in this embodiment, similarly to the case of FIGS. 2 and 3, control for the up and down movement of the support plate can be performed, and it is possible to cope with the operation of replenishing paper and feeding paper.

In the large-capacity tray according to the embodiment of the present invention, the paper feed roller disposed in the paper feed unit of the image recording apparatus may be a roller provided with a swingable arm or a half-moon roller. Is also applicable. As the sensor disposed above the sheet feeding unit, any of a sensor that outputs a plurality of detection signals by one and a sensor that disposes a sensor having two different functions can be used. In addition to the above configuration, any mechanism such as a motor or a gear transmission mechanism arranged in the drive unit may use any mechanism as long as it can perform an operation of intermittently raising a support plate supporting a sheet by several mm. be able to. Further, the large capacity tray of the present invention can be used for any image recording apparatus such as a facsimile machine, a copying machine, a printer, etc., and the size of the paper to be mounted on the large capacity tray is limited to one type. In addition, the function of raising the support plate in a horizontal state by the lift device can be favorably exhibited.

[0020]

As described above, the large-capacity sheet feeding apparatus of the present invention is constructed as described above. Therefore, in order to move the support plate of the large-capacity tray up and down, a lift device arranged on the support plate is linked. Since the mechanism is configured using the mechanism and the screw shaft, the mechanism of the lift device arranged on the large-capacity tray can be simplified. Further, even when the number of sheets stored on the support plate is very large, the operation of lifting the sheet using the lift device can be performed accurately, and the maintenance of the large capacity tray can be easily performed. it can. By providing the large-capacity tray of the present invention in any image recording apparatus, the number of sheet replenishments can be reduced, and it is possible to cope with the production of a large amount of recording paper.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an example in which a large capacity tray is provided in a facsimile machine.

FIG. 2 is an explanatory diagram showing a configuration of a large capacity tray of the present invention.

FIG. 3 is an explanatory diagram of a state in which a support plate of a large-capacity tray has risen to an upper limit position.

FIG. 4 is an explanatory view of another embodiment of a large capacity tray.

FIG. 5 is an explanatory diagram of a state in which a support plate has risen to an upper limit position in the large capacity tray of FIG. 4;

[Explanation of symbols]

1 image recording device, 2 paper feed section, 3 paper feed roller, 4 half-roller, 5 paper transport path, 7
Fixing device, 10 image forming unit, 11 developing unit, 12 developing roller, 15 photoconductor unit, 16 photoconductor drum, 17 LED, 18
Transfer roller, 19 controller, 20 facsimile reader, 27 platen, 29 CC
D, 30/40 Large capacity tray, 31/41 Support plate, 32/42 Lifting device, 33/43
Link mechanism, 36/46 drive unit, 37
・ 47 drive screw shaft, 38 ・ 48 motor, 39
· 49 gear transmission mechanism, 34 · 44 slide member, 45 support member.

Claims (3)

[Claims] 1. A large-capacity tray disposed in a paper feeding section of an image recording apparatus, wherein a supporting plate on which paper is placed is horizontally supported by a lifting device, and the lifting device is connected to a plurality of links via pins. A large-capacity sheet feeding device, comprising a link mechanism, wherein the link mechanism is deformed by rotating a horizontal screw shaft to move the support plate up and down. 2. The link mechanism according to claim 1, wherein the lift device is configured as a pantograph-shaped link mechanism in which four links are pin-connected in a rhombus shape, and upper and lower opposing pin-connecting portions are respectively attached to a support plate and a base of a tray. The large-capacity sheet feeding device according to claim 1, wherein the slide members provided at the left and right pin coupling portions are driven in a direction in which the slide members are separated from each other by a screw shaft. 3. The lift device is constituted by an X-shaped link mechanism in which a center portion of two links is connected by a pin, and a slide member disposed at a lower end portion of the two links of the link mechanism uses a screw shaft. And a support member disposed at the upper end of the two links is slid to the lower surface of the support plate, and the support plate for supporting the paper is moved up and down horizontally. The large-capacity sheet feeding device according to claim 1.