JPH0777931B2 - Sheet material feeding unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to sheet-shaped transfer paper, print paper, etc. (hereinafter referred to as sheet material) in an image forming apparatus such as a copying machine or a laser beam printer. The present invention relates to a sheet material feeding unit that improves the ability to feed. Here, the supply capacity is to increase the number of sheets loaded in the cassette by providing a plurality of sheet materials of the same size, or
It is possible to supply different kinds of sheet materials.

(B) Conventional Technology Conventionally, in an image forming apparatus, there is the following sheet material feeding device capable of adding another multi-stage cassette mechanism in addition to the existing single-stage cassette mechanism.

In some cases, the sheet material stacking cassette attached to the image forming apparatus from the beginning of manufacture is left as it is, and another sheet material feeding device is provided below or beside the apparatus. In this device, when attaching another device to the device body, the mounting accuracy decreases, and the sheet material fed from the cassette of another device is printed compared to the sheet material fed from the first cassette. The accuracy (mainly the accuracy in the width direction of the sheet material) becomes poor.

Some have been designed from the beginning to allow attachment of ancillary equipment. However, in a small-sized machine, a single-stage cassette is sufficient for ordinary users, and an expensive device that enables connection of multi-stage cassettes is not required.

(C) Problems to be Solved by the Invention By the way, when mounting a multi-stage cassette on both devices, a new means for identifying the size of the sheet material in the cassette in the device on the main body side is not used. Both devices were provided with identification means. As a result, the mechanism of both the devices becomes large, the cost becomes high, and it becomes difficult for the user to handle.

Therefore, the present invention increases the storage capacity of the cassette and makes full use of the identification means for identifying the size of the sheet material provided in the image forming apparatus without making any improvement to the existing image forming apparatus. The purpose of the present invention is to provide a small-sized, inexpensive, and simple sheet material feeding unit.

(D) Means for Solving the Problems The present invention is to contact a cassette storage unit that detachably stores a cassette to which an operating unit corresponding to the size of a sheet material to be stacked is attached, and an operating unit of the cassette. A sheet material feeding unit detachably attached to the cassette housing portion of the image forming apparatus including an identification means for identifying the size of the sheet material in the cassette. A unit-side storage unit for detachably storing the cassette, a transport unit for transporting the sheet material from the cassette stored in the unit-side storage unit to the image forming apparatus, and the sheet material feeding unit for the image forming apparatus. When attached, it is operated by the operation means of the cassette stored in the unit side storage portion and comes into contact with the identification means of the image forming apparatus. It is characterized by comprising a binding means.

Further, the sheet material feeding unit of the present invention is characterized in that the connecting means is a rod-shaped guide arm.

(E) Operation When the sheet material feeding unit is attached to the image forming apparatus, the connecting means is operated by the operating means of the cassette housed in the unit side storage portion, and the connecting means contacts the identifying means of the image forming apparatus. The identification means is activated. The image forming means obtains size information of the sheet material fed from the sheet material feeding unit side by the operation signal of the identifying means.

(F) Embodiment FIG. 1 shows a state in which a sheet material feeding unit (multistage cassette unit) B of the present invention is attached to a conventional image forming apparatus (laser beam printer in the illustrated example) A.

Before explaining the sheet material feeding unit B of the present invention,
The image forming apparatus A will be briefly described with reference to FIGS. In FIG. 2, there is a middle plate inside the cassette 2.
The sheet material 1 is mounted on the intermediate plate 21 so as to be vertically movable, and the uppermost sheet material is pressed against the feeding roller 3 by a compression spring 22.

FIG. 3 shows a state in which the cassette 2 is pulled out from the insertion port 23 in FIG.

Returning to FIG. 2 again, a plurality of (1 to 3) protrusions 25 are provided at the tip of the cassette 2 to indicate the size type of the sheet material loaded on the cassette 2. When the cassette 2 is inserted along the cassette guide (cassette accommodating part) 6, the tip of the cassette 2 is the tip 61 of the cassette guide.
Then, the cassette 2 is installed at a predetermined position.

At this time, the projection (operating means) 25 at the tip of the cassette is placed in the device A.
The detection switch (identification means) 62 is pressed to identify the type of the cassette 2, and a signal is sent to the controller (not shown) of the apparatus A. Based on the signal, the size of the sheet material 1 is identified, the scanning of the laser beam of the laser scanner 13 which will be described later is controlled, and the sheet material 1 is printed at a desired position.

The feeding roller 3 starts to rotate in response to the print command.
Separation pad 5 uses pin 9 as a fulcrum and spring 10
Is pressed against the feeding roller 3. The sheet material 1 is separated one by one by the feeding roller 3 and the separation pad 5 in pressure contact with the sheet, and is fed to the register roller 7.

The laser beam from the laser scanner 13 is a reflection mirror
It is irradiated to the drum 15 via 14. The register roller 7 starts rotating in synchronization with the irradiation of the laser beam and conveys the sheet material reaching the register roller 7 to the transfer unit 16. An image is formed on the surface of the drum 15 irradiated with the laser beam by the developing device 17, and the image is transferred onto the sheet material by the transfer unit 16. After the sheet material passes through the fixing unit 18 to fix the image, the sheet material is discharged onto the receiving table 20 by the discharging roller 19.

An embodiment of the sheet material feeding unit B of the present invention will be described with reference to FIG. 1, FIG. 4 and FIG.

FIG. 1 shows a state in which the projecting portion 30 of the sheet material feeding unit B slides along the cassette guide 6 of the image forming apparatus A, and the tip of the projecting portion 30 abuts the tip 61 of the guide 6. . The unit B can store two types of cassettes 32 and 36 in the unit side storage portions 32 ₁ and 36 ₁ , respectively. The configurations of the cassettes 32 and 36 are almost the same as those of the cassette 2 described above. The sheet material 1 is loaded on the middle plates 33, 37 of the cassettes 32, 36 and pushed up by the springs 34, 38.

A protrusion 31 is provided at the tip of the protruding portion 30 of the unit B, hits the member 11 supporting the separation pad 5 of the device A, and
The inclined surface of 11 is used to push down to form a gap between the feeding roller 3 and the separation pad 5.

Next, the function for displaying the size of the sheet material that can be stacked on the cassettes 32 and 36 will be described. In FIG.
A rod-shaped guide arm (coupling means) 48 attached to the unit B and movable freely in the left and right directions in the figure is lightly contactable with the detection switch 62 of the apparatus A. Fourth
In the figure, as an example, three detection switches (identification means) 62a, 62b, 62c and three rod-shaped guide arms (connection means) 48a, 48b, 48c corresponding to each are shown.
The guide arm 48a is moved by the protrusion (operating means) 32a of the cassette 32 to operate the detection switch 62a. In this way, by the selective actuation of the arms 48a, 48b, 48c,
Display sheet material dimensions.

The device A and the unit B may be connected by using a conventional connection lock mechanism. For example, if the device has a cassette lock mechanism, the lock mechanism can be used as it is.

In the illustrated example, these devices A and B are mounted on the same plane for use. However, if the unit B is small, the device A alone can support it in a cantilever manner.

The protruding portion 30 projects in the same shape as the cassette 2,
If a rotation fulcrum is provided on the base portion and it can be folded when removed, the handling becomes simple.

Although the tip of the protrusion 30 is inserted up to the same position as the cassette 2 of the apparatus A, the positioning may be performed in the vicinity of the insertion port 23 of the cassette 2.

Next, the drive system of the sheet material feeding unit B will be described with reference to FIG. The drive gear 55 (see FIG. 3) is connected to the motor 51 of device A. The driving force is transmitted to the conveying roller (conveying means) 45 by the gear 55, and the gear train is further transmitted.
It is transmitted to the drive gear 52 via 50. The transmitted driving force is controlled in rotation of the feeding roller 40 or 41 by an electromagnetic clutch 53 mounted coaxially with the feeding roller 40 or 41.

Although the conveying roller 45 is provided on the way, the conveying roller 45 can be omitted by rotating the feeding roller 40 or 41 a plurality of times.

Although the connection of the electric system between the device A and the unit B is not shown, they may be connected by a conventional connector or both may be connected by a cord.

Next, the widthwise reference when the sheet material is conveyed will be described. The feeding roller 3 and the separation pad 5 of the apparatus A are attached to the substantially central portion of the sheet material having the largest size to be used (FIG. 5). This is because the friction separation method makes it possible to achieve stable feeding by keeping the balance between the left and right by contacting the substantially central portion of the sheet material. The cassette 2 shown in FIG.
It is a cassette that was attached to a conventional device. The sheet material 1 is the largest size sheet material used. The small-sized sheet material 1'is formed into a cassette so that the sheet material 1'can be arranged substantially in the center, as shown in the drawing.

However, when connecting the sheet material feeding unit B,
Linking the size of the cassette with the controller of the apparatus A, like the upper cassette 36 of the unit B, is mechanically complicated and expensive. Therefore, by installing a small-sized sheet material 1'in the cassette based on the left side edge (starting side of writing of laser) of the maximum-sized sheet material 1 to be used like the upper cassette 36, laser writing is always started. Can be fed without changing the timing. However, it is necessary for the user to confirm the size of the sheet inserted in the cassette and issue an image command suitable for the sheet material.

The same applies to the lower cut.

The operation of the sheet material feeding unit B of this embodiment will be described. When the cassette 32 is inserted into the device B, the protrusion 32a attached to the tip of the cassette 32 moves the guide arm 48a to the left, and the detection switch 62a of the device A is activated. According to the print command from the apparatus A, either the upper or lower stage is selected first, and the feeding roller 40 or 41 starts rotating. By rotating the feeding roller, the cassette 32
Sheet separation claw 35 attached to the tip of (or 36)
(Or 39), the sheet material in the cassette 32 is conveyed.

The sheet material is guided between the guide plates 42 and 43 and is conveyed to the conveying roller 45 which is constantly rotating. The sheet material is further guided by the roller 45 between the guide plates 46 and 47. Guide plate 46,
Since the sheet material introduced between the spaces 47 has a gap between the feeding roller 3 and the separation pad 5, without stopping,
The sheet material passes smoothly between them without slowing it down. The sheet material guided to the register roller 7 is temporarily stopped in order to synchronize with the laser beam. Less than,
The sheet material is printed through the path described above.

The above is a description of one embodiment according to the present invention, but the present invention is not limited to this embodiment. For example, the sheet material feeding unit B may have only one cassette housing portion. In this case, it is preferable that a storage part having a different shape from the storage part of the apparatus A is configured so that cassettes of different sizes can be mounted.
Of course, the cassettes of the same shape may be loaded.

In addition, as shown in FIG. 1, even if there are multiple stages, the cassette 3
2, 36 and the cassette 2 in FIG. 2 may have the same size or different sizes.

Further, the rollers 40 and 41 may be controlled by another drive source provided in the unit B. In this case, the signals from the device A may be connected so that the rollers 40, 41 and the roller 3 rotate at the same time, or each time the sheet is fed by the roller 3, the sheet is fed from the cassette 36 or 32 by the roller 41 or 40. Alternatively, one sheet may be fed, and the sheet may be kept waiting under the roller 3 until the next sheet feeding command (apparatus A) is issued.

(G) Effect of the Invention According to the present invention, the storage capacity of the cassette can be increased without any improvement to the existing image forming apparatus, and the sheet material feeding unit is attached to the image forming apparatus. And the connecting means is operated by the operating means of the cassette stored in the unit side storage portion, and the existing identifying means of the image forming apparatus can be operated by the connecting means, so that the sheet material feeding unit can be downsized. Cost reduction and simplification can be achieved.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a state in which a sheet material feeding unit of the present invention is mounted on a known image forming apparatus. FIG. 2 is a vertical sectional view of the known image forming apparatus shown in FIG. FIG. 3 is a view similar to FIG. 2 and shows a state in which the cassette is removed.
FIG. 4 is a plan view of a connecting portion between the image forming apparatus and the sheet material feeding unit. FIG. 5 is an explanatory view of the sheet material stacking position in the cassette. A: image forming apparatus, B: sheet material feeding unit, 1
...... Sheet material, 2 …… Cassette, 3 …… Feeding roller, 5
...... Separation pad, 6 ...... Cassette guide, 7 ...... Register roller, 9 ...... pin, 10 ...... Spring, 11 ......
Support member, 13 ... Laser scanner, 14 ... Reflecting mirror, 15 ... Drum, 16 ... Transfer section, 17 ... Developer, 18 ...
… Fixing unit, 19 …… Discharging roller, 20 …… Catch, 21…
… Middle plate, 22 …… Spring, 23 …… Insertion port, 30 …… Projection part, 32,36 …… Cassette, 33,37 …… Middle plate, 34,38 …… Spring, 35,39 …… Separating claw , 40,41 …… Feeding roller, 4
2,43,44,46,47 …… Guide plate, 45 …… Conveying rollers, 48…
… Guide arm, 50 …… Gear train, 51 …… Motor, 52…
… Gears, 53 …… Electromagnetic clutch, 61 …… Detection switch.

Claims (2)

[Claims] 1. A cassette housing for detachably housing a cassette to which an operating means corresponding to a size of a sheet material to be loaded is attached, and a size of a sheet material in the cassette by contacting the operating means of the cassette. Identification means for identifying,
With respect to the cassette storage section of the image forming apparatus equipped with
In a detachably attached sheet material feeding unit, a unit side storage section for detachably storing the cassette to which the operating means is attached, and a sheet material from the cassette stored in the unit side storage section to an image forming apparatus. When the transporting means for transporting and the sheet material feeding unit are attached to the image forming apparatus, they are operated by the operating means of the cassette stored in the unit side storage portion to contact the identifying means of the image forming apparatus. A sheet material feeding unit, comprising: 2. The sheet material feeding unit according to claim 1, wherein the connecting means is a rod-shaped guide arm.