JPH0753538B2 - Sheet material feeding unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a sheet-shaped transfer paper, print paper or the like (hereinafter referred to as a 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 conveying device that improves the ability to supply paper. Here, the supply capability is to increase the number of sheets stacked in the cassette by providing a plurality of sheets of the same size, or to supply different types of sheet materials.

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

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 accessories. However, for 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 another device or an attached device is used, the sheet material must be fed from these devices to the image forming apparatus on the main body side. At this time, if the sheet material separating / feeding means on the main body side is left in operation, the sheet material will be greatly worn, and it is necessary to synchronize the separating / feeding means of both devices.

Therefore, the present invention increases the storage capacity of the cassette without improving the existing image forming apparatus, guarantees the printing accuracy, and obtains a small-sized, low-priced, and simple sheet material feeding apparatus. The purpose is to prevent abrasion of the existing sheet material separating and feeding means in the side device and to eliminate the need for synchronization adjustment.

(D) Means for Solving the Problem The present invention is directed to a main body side for removably accommodating a cassette having a predetermined size of sheet material and having an operating portion provided at a position corresponding to the sheet size of the sheet material. A cassette accommodating portion, a detecting means for detecting sheet size information in the cassette based on the operating portion of the cassette accommodated in the cassette accommodating portion, a feeding rotating body, and a separating means engaging with the feeding rotating body. A sheet material separating and feeding means for separating and feeding the sheet material having
A sheet material feeding unit that can be mounted in a cassette storage unit of an image forming apparatus, wherein a protrusion that is detachably fitted in the cassette storage unit of the image forming apparatus, and the protrusion is mounted in the storage unit. At that time, a releasing means for releasing the engagement of the sheet material separating and feeding means of the image forming apparatus, and a plurality of unit-side cassette accommodating portions on the upstream side of the projecting portion for detachably accommodating cassettes, respectively. A sheet size in the cassette, which is arranged between at least one of the unit-side cassette storage portions and the detection means of the image forming apparatus and is based on the operating portion of the cassette stored in the unit-side cassette storage portion. A transmission means for transmitting information to the detection means; and a feeding means for feeding the sheet material from the cassette housed in the unit-side cassette housing section. That.

(E) Operation Based on the above configuration, the cassette of the image forming apparatus is removed, and the protruding portion of the sheet material feeding unit is inserted therein.
At this time, the releasing means provided in the sheet material feeding unit releases the engagement between the feeding rotating body of the image forming apparatus and the separating means.

Then, in this state, the cassettes can be detachably accommodated in a plurality of cassette accommodating portions of the unit, and sheet materials of various sheet sizes in the cassettes can be supplied to the image forming apparatus. At this time, the sheet size information of the unit is transmitted to the image forming apparatus.

As a result, the sheet material is fed similarly to the apparatus on the main body side.

(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 describing the sheet material feeding unit B of the present invention, the image forming apparatus A will be briefly described with reference to FIGS. 2 and 3. In FIG. 2, an intermediate plate 21 is mounted in the cassette 2 so as to be vertically movable, the sheet material 1 is loaded on the intermediate plate 21, and the compression spring 22 causes the uppermost sheet material to move to a feeding roller (feeding roller). It is pressed against the (sending body) 3.

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 6, its front end abuts on the front end 61 of the cassette guide, and the cassette 2 is set at a predetermined position.

At this time, the projection 25 at the tip of the cassette pushes the detection switch 62 of the apparatus A, identifies the type of the cassette 2, and sends a signal 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 roller 3 and the pad 5 are collectively referred to as sheet material separating and feeding means.

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. The configuration of the cassettes 32 and 36 is the same as the cassette 2
It is almost the same as that of. 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.

Instead of pushing down the separation pad 5, the feeding roller 3 may be pushed up. A sheet material overrun detecting means is provided on the entrance side of the feeding roller 3 so that the separating and feeding means (3, 5) can be provided only when a double feeding is performed.
May be activated.

Instead of providing the protrusion 31, an electromagnetic solenoid for releasing the separating and feeding means (3, 5) of the apparatus A in response to an operation signal of the feeding roller 40 or 41 may be provided.

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 guide arm 48 attached to the unit B and movable freely in the left-right direction in the figure is in light contact with the detection switch 62 of the apparatus A. In FIG. 4, as an example, 3
3 corresponding to each detection switch 62a, 62b, 62c
Individual guide arms 48a, 48b, 48c are shown. Cassette 32
The guide arm 48a is moved by the protrusion 32a to activate the detection switch 62a. In this way, the arms 48a, 48
The size of the sheet material is displayed by the selective operation of b and 48c. 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 can be supported 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 45 by the gear 55, and is further transmitted to the driving gear 52 via the gear train 50. The transmitted driving force is applied to the electromagnetic clutch 53 mounted coaxially with the feeding roller 40 or 41.
Thus, the rotation of the feeding roller 40 or 41 is controlled.

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 cassette.

The operation of the sheet material feeding unit B of the present invention will be described. By inserting the cassette 32 into the unit B, the protrusion 32a attached to the tip of the cassette 32 is guided and
Move the arm 48a to the left to detect the device A detection switch 62a.
Operate. 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) Effects of the Invention Since the sheet material feeding unit according to the present invention is as described above, it has the following effects. That is, according to the present invention, since the sheet material feeding unit includes the protruding portion that can be detachably fitted into the cassette housing portion on the image forming apparatus side, the sheet material feeding unit can be easily operated by the same operation as that of the normal cassette mounting. It can be attached to the image forming apparatus.

Further, according to the present invention, a cassette storage portion is formed on the sheet material feeding unit side, and the cassette is detachably stored in the cassette storage portion. Therefore, the size of the sheet material can be changed only by exchanging the cassette stored in the cassette storage portion, and the operation is simplified. Further, since the sheet size information in the cassette is transmitted to the detecting means on the image forming apparatus side through the transmitting means from the operating portion provided on the cassette, it is possible to appropriately use the controller on the image forming apparatus side. It is possible to print.

Further, when the sheet material feeding unit is mounted, the engagement of the sheet material separating and feeding means is released by the releasing means. Therefore, when the sheet material is fed by the feeding means on the side of the sheet material feeding unit, the feeding rotator of the sheet material separating and feeding means and the separating means do not come into contact with each other, and as a result, the feeding rotator. Wear can be prevented.

Further, as described above, the mounting of the sheet material feeding unit is carried out by utilizing the existing cassette housing portion on the image forming apparatus side, and the sheet size is detected by the existing detecting means and cassette on the image forming apparatus side. It is not necessary to form a special mechanism on the side of the image forming apparatus because it is performed by using the operating part of Therefore, the image forming apparatus does not become expensive although the effect of improving the sheet material supply capability and the like can be obtained as described above.

Furthermore, since a plurality of cassette storage portions are provided on the sheet material feeding unit side, the sheet material supply capacity can be improved. That is, if a plurality of cassettes in which sheet materials of the same size are stored in the plurality of cassette storage portions are installed, the sheet material supply capacity is improved in that the number of sheets to be supplied is increased, and different types of sheet materials are stored. If a plurality of cassettes are mounted, it is possible to supply different kinds of sheet materials, and the supply capacity is improved.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a state in which the sheet material feeding unit of the present invention is attached to an image forming apparatus. FIG. 2 is a vertical cross-sectional view of the 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, 24,32 ′, 32a …… Working part (projection), 33,37 …… Middle plate, 34,38 …… Spring, 35,39…
… Separation claws, 40, 41 …… Feed rollers, 42, 43, 44, 46, 47 ……
Guide plate, 45 ... Conveying roller, 48,48a, 48b, 48c ... Transmission means (guide arm), 50 ... Gear train, 51 ... Motor, 52 ... Gear, 53 ... Electromagnetic clutch, 62, 62a, 62b, 62c
...... Detection means (detection switch).

Claims (4)

[Claims] 1. A main body side cassette storage unit for removably storing a cassette having a predetermined size of sheet material and having an operating portion provided at a position corresponding to the sheet size of the sheet material, and the cassette storage unit. A sheet material having a detecting means for detecting sheet size information in the cassette based on the operating part of the cassette housed in the cassette, a feeding rotating body, and a separating means engaging with the feeding rotating body; A sheet material feeding unit that can be mounted in the cassette housing portion of the image forming apparatus with respect to the image forming apparatus that comprises a sheet material separating and feeding means for A protruding portion that freely fits; a releasing means that releases the engagement of the sheet material separating and feeding means of the image forming apparatus when the protruding portion is mounted in the storage portion; and an upstream side of the protruding portion. There A plurality of unit-side cassette storage sections each of which stores a cassette detachably, and at least one of the unit-side cassette storage sections and the detection means of the image forming apparatus are arranged, and the unit-side cassette storage section is provided. Transmitting means for transmitting the sheet size information in the cassette based on the operating portion of the cassette stored in the cassette to the detection means, and feeding means for feeding the sheet material from the cassette stored in the unit-side cassette storage portion Sheet material feeding unit equipped with. 2. The sheet material feeding unit according to claim 1, wherein the releasing means releases the separating feeding means by pushing it. 3. The sheet material feeding unit according to claim 1, wherein the releasing means pushes and releases the feeding rotating body. 4. The sheet material feeding unit according to claim 1, wherein said releasing means is an electric means and is released in response to a releasing signal.