JP2913432B2 - Document fall prevention device for image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a document conveying device provided on an upper surface of a main body of the apparatus, and more particularly to a device for preventing a document from dropping from the document conveying device.

[0002]

2. Description of the Related Art Conventionally, in a copying machine or the like, it is known to provide a document conveying device on an upper surface of a copying machine body. In this document feeder, documents are stacked on document support means such as a document tray, and the documents on the document support means are sent out one by one by a sending means such as a roller.

The document feeder is supported by the body of the copying machine via hinges so as to open and close the upper surface of the body of the copying machine so as to be vertically rotatable.

On the other hand, in a copying machine or the like, the copying machine main body is configured to be able to be divided into an upper half and a lower half, and the upper half is supported so as to be vertically rotatable about a fulcrum at one end of the lower half. It is known that the upper half is rotated upward to open the inside of the apparatus main body so that inspection, repair, removal of a jam sheet, and the like can be performed.

[0005]

However, according to the above-mentioned prior art, when the upper half of the apparatus main body is turned upward to open the apparatus main body, or when the document feeder is turned upward to rotate the apparatus main body. When the upper surface of the document is opened, if there is a document on the document support means of the inclined document feeder, the document may slide down from the document support means.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus for preventing a document from dropping from a document supporting means of a document conveying apparatus which is inclined when the upper half of the apparatus body is rotated upward to open the apparatus body. The object of the present invention is to provide a document fall prevention device.

[0007]

In order to achieve the above object, the present invention comprises the following means.

An opening detecting means for detecting that the upper half is opened, and an open detecting means provided to be capable of pressing and separating from the original on the original supporting means. When the opening detecting means detects that the upper half is opened, the original is opened. Document pressing means pressed against

A jam detecting means for detecting a copy sheet conveyance failure of the apparatus main body, and a press-contact / separation mechanism for the document on the document support means, are pressed against the document when the sheet conveyance failure is detected in the apparatus main body. Document holding means.

An open detecting means for detecting that the original conveying device is separated from the platen, and an original pressing means for pressing the original based on the detection result of the open detecting means are provided, and the pressing means is mounted on the original supporting means. A document feeder that feeds out the original from the top sheet consists of an original feed roller that is provided so as to be able to press and separate the top sheet of the original, and feeds the original loaded on the original support means from the bottom sheet. The apparatus is constituted by a weight member for adding a weight to the uppermost sheet in a state where the feeding means is pressed against the lowermost sheet.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention can be applied to various image forming apparatuses such as a copying machine, a printer, a facsimile, and the like. As an example, a copying machine will be described below with reference to FIGS.

As shown in FIG. 1, a platen P is provided on an upper surface of an image forming apparatus main body, for example, a copying machine main body M. A document conveying device F is provided so as to cover the platen P.

The document feeder F is supported by the copying machine main body M1 so as to be vertically rotatable (see FIG. 7). The copying machine main body M has a built-in image forming mechanism that exposes the original on the platen P and copies the original onto a sheet by the reflected light.

As shown in FIG. 1 to FIG.
Is configured to be splittable into an upper half body M1 and a lower half body M2, and the upper half body M1 is supported so as to be vertically rotatable about a fulcrum 1 on one end side of the lower half body M2.

At the time of inspection, repair, and removal of a defective sheet, for example, a jam sheet, the upper half body M1 is rotated upward so that the inside of the copier main body M can be opened. As shown in FIG. 1, the document feeder F of this example
A document support means for loading documents such as document tray 2;
Separating means 3 for separating and feeding the originals on the original tray 2 into one sheet, conveying means such as a conveying belt 4 for conveying the originals from the separating means 3 along the platen P, and discharged from the conveying belt 4 And a discharge tray 5 for storing originals.

The separating means 3 is a feeding means such as a pick-up roller 6 which can press and separate the uppermost sheet on the document tray 2 and presses the sheet to feed the original, a sheet feeding roller 7 rotating in the feeding direction, and a sheet feeding means. A separation belt 8 that rotates in a direction opposite to the roller 7 and separates the original into one sheet;
And its pinch roller 10.

The axis of the pickup roller 6 is the swing arm 1
1 is connected to the shaft of the paper feed roller 7. The pickup roller 6, the paper feed roller 7, the separation belt 8, and the like are rotated by a paper feed motor (not shown).

When one document is fed, the paper feed motor rotates forward, the pickup roller 6 and the paper feed roller 7 rotate in the forward direction, and the separation belt 8 rotates in the reverse direction. Then, the swing arm 11 descends, and the pickup roller 6 is pressed against the uppermost sheet at a constant pressure by the action of a spring clutch (not shown).

On the other hand, when the paper feed motor rotates in the reverse direction, the pickup roller 6 rises and is separated from the original.

In this example, as shown in FIG. 2, the lower half M2 is provided with an opening detecting means for detecting that the upper half M1 has been rotated upward, for example, an opening sensor S1.
When the opening sensor S1 detects the upward rotation of the upper half body M1, the pickup roller 6 is lowered and the original is pressed down. That is, the pickup roller 6 serves as a document pressing unit.

However, an empty sensor S as an empty detecting means for detecting the presence or absence of a document on the document tray 2
2 detects that there is no document on document tray 2,
The pickup roller 6 is maintained at a raised position without descending.

The various driving controls described above are performed by control means (not shown) such as a CPU.

The operation of the embodiment constructed as described above will now be described with reference to FIGS. 1 to 3 and the flowchart of FIG.

When a document is set on the document tray 2, the empty sensor S2 is turned on. In this state, the copying machine main body M
When the start key (not shown) is turned on, the paper feed motor rotates forward, the pickup roller 6 and the paper feed roller 7 rotate in the forward direction, and the separation belt 8 rotates in the reverse direction.

Then, the swing arm 11 is lowered, and the pickup roller 6 is pressed against the uppermost sheet with a constant pressure by the action of a spring clutch (not shown). The original is sent out by the pickup roller 6, separated into one sheet by the paper feed roller 7 and the separation belt 8, and sent to the registration roller 9.

After the registration (skew correction), the sheet is conveyed and set on the platen P by the conveying belt 4, and is discharged from the conveying belt 4 to the discharge tray 5 after the copying is completed.

Now, for example, when the upper half body M1 is rotated upward to open the copying machine body M as shown in FIG. 2 in order to remove a jam sheet inside the copying machine body M, the opening operation is performed. Is detected by the open sensor S1.

Then, based on this detection signal, the paper feed motor rotates forward, the pickup roller 6 descends while rotating, and after a predetermined time (pulse) elapses, the paper feed motor is stopped, and the pickup roller 6 also stops. Since the document on the document tray 2 is pressed down by the pickup roller 6, the document can be prevented from sliding down from the inclined document tray 2.

However, when the empty sensor S2 detects that there is no document on the document tray 2, such an operation is not necessary, and the pickup roller 6 does not move down and keeps the ascending position.

After the jammed sheet is removed, when the upper half body M1 is lowered and closed, the sheet feeding motor rotates in the reverse direction and is separated from the original.

The present invention is not limited to the above embodiment, and various modifications can be made.

For example, as shown in FIG.
A jam sensor S3 serving as a jam detecting means may be provided inside the document feeder to press a document on the document tray 2 of the document feeder F when a sheet jam is detected.

If a sheet jam occurs in the copying machine main body M, the copying operation of the copying machine is automatically stopped, and the upper half M1 is opened to take out the jammed sheet.

Further, the detecting means may be provided in the document conveying device without providing the detecting means in the image forming apparatus main body. The example shown in FIG. 5 is a document feeder F (see FIG. 1).
Is provided with an inclination detecting means 21 for detecting the inclination of the document feeder F.

S4 is a photo sensor. The weight 22 is hung on a shaft 23 and always maintains a vertical orientation regardless of the presence or absence of inclination. 24 turns off the photo sensor S4
It is a shielding plate. When the document feeder F changes from the normal position to the tilted position, the state changes from FIG. 5A to FIG. 5B, and the shielding plate 24 turns off the photo sensor S4 to detect that the document feeder F is tilted. I do.

In the first embodiment, the original feeding means such as the pickup roller 6 provided on the uppermost sheet so as to be able to be pressed and separated is used as the original pressing means. However, as shown in FIG. 6, in the case of a type in which the feeding means 31 is pressed against the lowermost sheet and the weight means 32 is provided on the uppermost sheet so as to be able to be pressed and separated, the weight means 32 is used for the original. It becomes a holding means.

Further, as shown in FIG. 7, the document feeder F is generally rotatable up and down via a hinge 41 for opening and closing the upper surface of the image forming apparatus main body such as the copying machine main body M. Open detection means 42 is provided for detecting whether the document feeder F has opened or closed the top surface of the copying machine main body M. When the document feeder F is rotated upward, the document is pressed. You may.

[0038]

According to the present invention described above, the upper half and the lower half can be divided so that the upper half is vertically rotatable about a fulcrum at one end of the lower half. A document transport device for transporting a document toward a platen mounted on the upper surface of the upper half body and transporting the document to the platen provided on the upper surface of the device body, and a document support unit provided on the document transport device for loading the document. When the upper half is opened upward, the original pressing means is pressed against the original and presses the original, so that the original can be prevented from dropping from the original supporting means.

Further, since the original is pressed even when the original conveying device is separated from the platen of the apparatus main body, the original can be prevented from dropping.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a longitudinal section of an embodiment of the present invention.

FIG. 2 is a closed state diagram of the image forming apparatus main body of the embodiment.

FIG. 3 is an open state diagram of the image forming apparatus main body of the embodiment.

FIG. 4 is a flowchart for explaining the operation of the embodiment.

FIG. 5 is an operation state diagram of a detection unit according to another embodiment.

FIG. 6 is a schematic diagram showing a document pressing unit according to still another embodiment.

FIG. 7 is an open state diagram of a document feeder according to still another embodiment. M Copying machine main body (image forming apparatus main body) M1 Upper half body M2 Lower half body F Document feeder 1 Support point 2 Document tray (document supporting means) 6 Pickup roller (document holding means) 21 Tilt detecting means 32 Weight means (document holding) 42) Open detection means of the document feeder S1 Open sensor (open detection means of the apparatus main body) S2 Empty sensor S3 Jam sensor (jam detection means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI G03G 15/00 526 G03G 15/00 526 (58) Field surveyed (Int.Cl. ⁶ , DB name) B65H 7/06 B65H 1 / 06 B65H 3/54 310 B65H 31/26 G03G 15/00 107 G03G 15/00 526

Claims (5)

(57) [Claims] An apparatus main body configured to be splittable into an upper half and a lower half, wherein the upper half is supported so as to be vertically rotatable about a fulcrum at one end of the lower half; A document feeder mounted on the upper surface of the upper half body and transporting the document toward a platen provided on the upper surface of the apparatus main body; and a document supporter provided in the document transporter and stacking the document. In the image forming apparatus, an opening detecting unit that detects that the upper half is opened, and an upper half that is provided so as to be able to press and separate from the original on the original supporting unit and that the upper half is opened by the opening detecting unit And a document pressing means pressed against the document when detecting that the document has fallen. 2. An apparatus main body which is configured to be able to be divided into an upper half and a lower half, wherein the upper half is vertically rotatable around a fulcrum at one end of the lower half. A document feeder mounted on the upper surface of the upper half body and transporting the document toward a platen provided on the upper surface of the apparatus main body; and a document supporter provided in the document transporter and stacking the document. In the image forming apparatus, a jam detecting means for detecting a copy sheet conveyance failure of the apparatus main body, and a pressurized / separable sheet provided on the document on the document supporting means for detecting a sheet conveyance failure in the apparatus main body. Then, a document pressing means pressed against the document, and a document drop prevention device for an image forming apparatus, comprising: 3. An image forming apparatus main body and an image forming apparatus main body mounted on an upper surface of the image forming apparatus main body.
The platen is detachable from the platen provided on the upper surface.
And a document support provided on the document transport device for loading documents.
An image forming apparatus comprising: means, and to detect that the document feeder is separated from the platen
Opening detection means for pressing the original based on the detection result of the opening detection means.
A document holding means , wherein the document holding means is stacked on the document supporting means;
The uppermost sheet of the original that is
Document feeding that feeds the original loaded on the support means from the top sheet
An image forming apparatus, comprising:
Paper fall prevention device. 4. An image forming apparatus main body and an apparatus main body mounted on an upper surface of the apparatus main body.
The platen is detachable from the platen provided on the upper surface.
And a document support provided on the document transport device for loading documents.
Means for feeding the original loaded on the original supporting means from the lowermost sheet
An image forming apparatus comprising: means out, and to detect that the document feeder is separated from the platen
Opening detection means for pressing the original based on the detection result of the opening detection means.
A document holding means , wherein the document holding means is stacked on the document supporting means;
Is placed on the top sheet of the original that can be pressed and separated.
A weight is attached to the top paper with the feeding means pressed.
Image shape characterized by comprising a weight member to be added
Document fall prevention device of the printer. 5. A method for detecting the presence or absence of a document on said document supporting means.
Empty detecting means is provided.
When the means detects that there is no original, the original pressing means
Control means for keeping
Claim 1, claim 3, or claim 4
A document fall prevention device for the image forming apparatus according to the above.