JPH055958A - Carrier sheet - Google Patents

Abstract

PURPOSE:To offer a carrier sheet that the trailing edge of an original can be precisely detected even when the carrier sheet is obliquely carried. CONSTITUTION:A notch 15 extending to the trailing edge of the carrier sheet 10 from a position which is prescribed-distance inside from the leading edge 13 of the sheet 10 is formed on the sheet 10. The width of the notch 15 is gradually made wider according as it goes toward the trailing edge. Therefore, even when the sheet 10 is obliquely carried, a trailing edge sensor is not superposed to the side of the notch of the sheet 10 on the way of the notch and the trailing edge of the original can be correctly detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier sheet which is used as a document conveyance assisting tool when a document is conveyed and read.

[0002]

2. Description of the Related Art In a facsimile machine or an electrophotographic copying machine capable of making a copy of a large-sized original such as Japanese Industrial Standard A-line No. 0 (hereinafter referred to as "A0 size"), the original is conveyed and read. In this case, a carrier sheet is often used as a document transportation aid. Actual Kaihei 1
An example of a carrier sheet used in a facsimile machine is shown in Japanese Patent Laid-Open No. 122663 and Japanese Patent Application Laid-Open No. 2-149061 which is a prior application of the present applicant.

That is, the former publication discloses a carrier sheet in which an elongated notch having a length capable of exposing the rear end of a document is formed from the rear end toward the front end. According to this carrier sheet, even when the document length is shorter than the carrier sheet, the document trailing edge exposed from the notch can be detected, and the document length can be accurately grasped.

Further, the latter publication discloses a carrier sheet in which an elongated cutout path is formed which starts from a position inside a predetermined distance from the front end of the sheet and extends to the rear end of the sheet in parallel with the sheet conveying direction. Has been done. If this carrier sheet is used, the trailing edge of the document can be detected regardless of the size of the carrier sheet, and reading can be performed according to the size of the document.

[0005]

By the way, when a conventional carrier sheet as described above is used as a document conveyance assisting tool and the carrier sheet is conveyed in a slightly slanted manner instead of being straight in the conveying direction, In the case of so-called skew feeding, there are cases where the trailing edge of the original cannot be accurately detected.

A more specific description will be given with reference to the drawings. For example, consider the case where the carrier sheet 1 is conveyed in a skewed manner as shown in FIG. In such a case, first, the rear end center 4 of the document 2 exposed from the cutout path 3 is detected by the sensor 5 (see FIG. 2B), and when the carrier sheet 1 is further conveyed, the side 6 in the middle of the cutout path 3 is detected by the sensor. A situation occurs in which it is detected again by 5 (see FIG. 2C).

Therefore, the object of the present invention is to provide a carrier sheet which does not have the above-mentioned drawbacks.

[0008]

SUMMARY OF THE INVENTION The present invention is a carrier sheet used as a document conveyance assisting tool when a document is conveyed and read, from a position inside a predetermined distance from the leading edge of the sheet. It is characterized in that a notch formed so as to start and extend to the rear end of the sheet in the sheet conveying direction and the width thereof gradually increases.

[0009]

According to the carrier sheet of the present invention, the notch formed in the carrier sheet gradually becomes wider toward the rear end in the carrying direction. Therefore, even when the carrier sheet is conveyed in a state that it is slightly inclined with respect to the conveying direction, the sensor does not overlap the middle side of the cutout or the like, and the trailing edge of the document can be accurately detected.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view of a carrier sheet according to an embodiment of the present invention. The carrier sheet 10 is formed by stacking two base sheets 11 and a transparent cover sheet 12, and the base sheet 11 and the cover sheet 12 are connected to each other at the front end side 13.

The carrier sheet 10 according to this embodiment is provided with a notch 15 which starts at a position inside a predetermined distance from the leading edge 13 and extends to the trailing edge of the sheet in the sheet conveying direction. The width of the notch 15 gradually increases toward the rear end. This is the feature of this embodiment. By doing so, as shown in FIGS. 3A and 3B, even when the carrier sheet 10 is conveyed in a skewed manner, the trailing edge detection sensor 62 is also included.
Switches from ON to OFF or from OFF to ON only when the rear edge of the document 14 exposed from the notch 15 is detected,
The trailing edge detection sensor 62 does not overlap the side of the cutout 15 of the carrier sheet 10.

Next, a case of actually copying an original using the carrier sheet 10 will be described. Figure 4
FIG. 5 is a simplified cross-sectional view showing the internal structure of a copying machine equipped with a carrying device according to an embodiment of the present invention, and FIG.
FIG. 5 is a perspective view showing an external configuration of the copying machine shown in FIG. 4. This copying machine is for obtaining a copy image of a large-sized document such as A0 size, and while conveying the document,
The document surface is illuminated and scanned by a fixedly arranged optical system, and an image is formed based on the illumination and scanning.

The body 21 of the copying machine has caster wheels 2 at the bottom.
It is mounted on a moving deck 23 provided with 2. A roll paper supply unit 25 for supplying copy paper is provided in association with the moving deck 23. The roll paper 24 is accommodated in the roll paper supply unit 25, and the roll paper 24 is supplied to the paper feed path 51 in the copying machine main body 21 by the paper feed roller 26.

On the upper part of the main body 21 of the copying machine, the sheet conveying section 30 for conveying the carrier sheet 10 on which the original 14 is set by switching the conveying direction to the forward direction R1 or the reverse direction R2.
Is provided. The copying operation is performed when the carrier sheet 10 is conveyed in the forward direction R1, and when a plurality of sheets are copied, the sheet conveying unit 30 alternately conveys the carrier sheet 10 in the forward direction R1 and the reverse direction R2. ..

When copying a plurality of sheets in this way, the carrier sheet 10 on which the original 14 is set is
Since the conveyance is repeated alternately in the forward direction R1 and the reverse direction R2, the carrier sheet 10 may be conveyed a little obliquely with respect to the conveying direction during that time, rather than being straight. In this embodiment, even in such a case, the trailing edge of the document is correctly detected, as will be described later.

The sheet conveying section 30 is provided with the carrier sheet 10.
For slit exposure of the first conveying roller 32, which is driven when the first leading edge detection switch 31 for detecting the leading edge of the document (that is, the leading edge of the document 14) is turned on, and the document 14 set on the carrier sheet 10. A second conveying roller 34 provided at a position facing the transparent plate 33 to bring the carrier sheet 10 into close contact with the transparent plate 33, and a third conveying roller 3 for discharging the carrier sheet 10 after exposure.
5 and. First and second transport rollers 32,
A second tip detection switch 36 is further arranged between 34. Reference numeral 38 is a reversing portion for reversing the direction of the carrier sheet 10 to prevent the carrier sheet 10 from falling to the back surface of the copying machine main body 21.

In relation to the transparent plate 33, the carrier sheet 1
A light source 37 for illuminating the document surface of the document 14 set to 0 is fixedly arranged. The light from the light source 37 is applied to the document surface via the transparent plate 33. Then, the reflected light from the surface of the document 14 is guided to the surface of the photoconductor drum 40 provided in the copying machine main body 21 by the SELFOC lens 38. The surface of the photosensitive drum 40 before being exposed by the light from the SELFOC lens 38 is uniformly charged by the charging corona discharger 41. Therefore, an electrostatic latent image corresponding to the original image is formed on the surface of the photosensitive drum 40 after exposure. This electrostatic latent image is visualized as a toner image by the developing device 42, and this toner image is guided to the vicinity of the transfer corona discharger 44 as the photosensitive drum 40 rotates in the direction of arrow 43.

On the other hand, the roll paper 2 guided to the paper feed path 51
Further, 4 is a conveyance roller 52 and a registration roller 53.
Is guided to the vicinity of the transfer corona discharger 44. Then, the toner image on the surface of the photosensitive drum 40 is transferred to the roll paper 2 by the corona discharge in the transfer corona discharger 44.
Transferred to 4. The roll paper 24 after the transfer is peeled from the surface of the photoconductor drum 40 by corona discharge in the peeling corona discharger 45, and is further guided to the fixing device 55 through the transport path 54. In the fixing device 55, the toner on the surface of the roll paper 24 is fixed, and the roll paper 24 after the toner is fixed is discharged from the discharge roller 56 to the outside of the copying machine main body 21. Further, the trailing end of the supplied roll paper 24 is cut by, for example, a cutter 57 provided between the transport roller 52 and the registration roller 53. Meanwhile,
The toner remaining on the surface of the photosensitive drum 40 after the transfer of the toner image is removed by the cleaning device 46 and is prepared for the formation of the next electrostatic latent image.

On the upper surface of the copying machine main body 21, the forward direction R
1, the transport path 6 is provided on the upstream side of the sheet transport unit 30.
1 is formed up to the position where it projects from the upper surface of the copying machine main body 21. Then, at a predetermined position of the transport path 61,
A rear end detection sensor 62 is provided. When copying one sheet, when the trailing edge of the document 14 is determined based on the output of the trailing edge detection sensor 62, the cutter 57 provided in the sheet feeding path 51 is operated to cut the roll sheet 24. To be done. In this case, from the cutter 57 to the transfer position 40b
The length of the paper feed path for the roll paper 24 to reach the position from the trailing edge detection sensor 62 to the document exposure position 64 is longer than the length from the exposure position 40a of the photosensitive drum 40 to the transfer position 40b. Is set to be longer. Therefore, if the cutter 57 is operated at the time when the trailing edge of the original 14 is discriminated based on the output of the pair of trailing edge detection sensors 62, the roll paper with the image corresponding to the trailing edge of the original 14 cut is cut. It can be formed at the rear end of 24.

Of course, the sheet supply path length and the roll paper 2
The relationship with the paper feed path length of 4 can be set arbitrarily,
In this case, the cutter 57 may be operated at a timing deviated by a predetermined timing from the timing at which the trailing edge of the document 14 is detected based on the detection output of the pair of trailing edge detection sensors 62. FIG. 6 is a block diagram showing the electrical construction of the copying machine, and only the portions related to the features of this embodiment are shown. The output of the rear end detection sensor 62 is given to the control unit 70 including a CPU and the like. Further, the detection outputs of the tip detection switches 31 and 36 are also given to the control unit 70. The control unit 70 controls the transport rollers 32,
While controlling the document clutch 72 for 34, 35, etc. to convey the carrier sheet 10, the paper feed roller 26,
The roll paper clutch 73 for the transport roller 52, the registration roller 53, and the like is controlled to supply the roll paper 24. Further, the control unit 70 controls the light source 37.

Further, the control unit 70 includes a cutter solenoid 7
The cutter 57 is operated by turning 1 on / off to cut the roll paper 24. FIG. 7 is a flow chart for explaining the control operation in the control unit 70 of FIG. The control operation of the control unit 70 will be described with reference to FIG. When it is determined that the leading edge detection switch 31 is turned on (step S1), the light source 37 is turned on (step S2), then the document clutch 72 is turned on (step S3), and the document 14 held on the carrier sheet 10 is conveyed. Is started.

When it is determined that the leading edge detection switch 36 is turned on (step S4), the document clutch 72 is once turned off (step S5), and the transport timing of the document 14 coincides with the transport timing of the roll paper 24. It is determined whether or not (step S6). When the above timings match, the clutch 72 is turned on again (step S
7), copy processing is performed (step S8). Next, it is determined whether or not there is a detection signal from the trailing edge detection sensor 62 (step S9), and if there is a detection signal, the cutter solenoid 71 is turned on (step S10), the cutter 57 is operated, and the roll paper 24 is cut. To do. Then, the copy process ends (step S11).

The above description is based on the carrier sheet 10.
However, the carrier sheet according to the present invention can also be used in a facsimile device and other image reading devices.

[0024]

By using the carrier sheet according to the present invention, the trailing edge of the original can be correctly identified even when the carrier sheet is conveyed in a so-called skewed state.

[Brief description of drawings]

FIG. 1 is a perspective view of a carrier sheet according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining the problem of detecting the trailing edge of a document when a conventional carrier sheet is used.

FIG. 3 is a diagram for explaining the principle of determining the trailing edge of an original when the carrier sheet according to this embodiment is used.

FIG. 4 is a simplified cross-sectional view showing the internal structure of a copying machine equipped with a carrying device according to an embodiment of the present invention.

5 is a perspective view showing an external configuration of the copying machine shown in FIG.

6 is a block diagram showing an electrical configuration of the copying machine shown in FIG.

7 is a flowchart for explaining a control operation in a control unit 70 in FIG.

[Explanation of symbols]

 10 Carrier Sheet 14 Document 15 Notch 62 Rear Edge Detection Sensor

Claims (1)

Claim: What is claimed is: 1. A carrier sheet used as a document transportation assisting tool for transporting and reading a document, the carrier sheet starting from a position inside a predetermined distance from the leading edge of the sheet,
A carrier sheet, characterized in that it has a notch formed so as to extend to the rear end of the sheet in the sheet conveying direction and the width thereof gradually increases.