JPS60230158A - Sheet material feeder - Google Patents

Abstract

PURPOSE:To prevent an accident such as sepn. failure by providing a means for detecting paper and a paper guide and a means feeding diagonally the paper to a sheet material conveying path, feeding and conveying the paper surely even if the paper is set slightly surely by manual insertion, detecting the defective conveyance of the fed paper, if such defect arises, and stopping the copying operation. CONSTITUTION:The transfer paper 2 fed by feed rollers moves in an arrow direction A through the conveying path 3. If the paper 2 fails to move along the paper guide 9, the paper is nipped by the driving roller 5 and driven ball 7 of the means 4 for feeding diagonally the paper provided on the upstream side of the guide 9 and is advanced while moved toward the left side B so that the paper moves along the guide 9. If a paper detecting switch 11 contacts with the paper 2, the copying operation is continued as it is by a control means but the control means stops the copying device when the paper 2 fails to contact with the switch 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feeding failure detection device for an image support material of an image forming apparatus such as an electronic copying machine, which is provided in a manual paper feeding section, for example.

In an electronic copying apparatus capable of copying using sheet materials of different sizes, it is necessary to always maintain the position of the sheet material constant and guide it to the transfer section.

This is extremely important. That is, if the sheet material is supplied to the transfer target section while the position of the sheet material is shifted, not only the transferred image will be shifted, but also there is a risk that it will not be able to be peeled off when it is to be peeled off from the photosensitive drum. This tendency is more common when sheet materials of a predetermined size are fed from a manual paper feeder than when sheet materials of a predetermined size are automatically fed from a paper feeder.

This is because, when paper is automatically fed, the sheet material is usually placed in a paper feed cassette or the like. That is, it is correctly installed at a predetermined position.

On the other hand, in the case of manual paper feeding, there is a high possibility that the user will set the sheet material arbitrarily.

In order to prevent such drawbacks, some conventional devices are equipped with a sheet material detection means at a position corresponding to the end of the sheet material in the direction orthogonal to the conveyance direction of the sheet material during the paper feeding process. (Utility Model Publication No. 57-19711) 0 The purpose of the above device is to detect a jammed sheet material and stop the operation of a device such as an electronic copying device. However, the most desirable thing for the device is to prevent jams from occurring.

The present invention reliably feeds and transports sheet materials even if the setting of the sheet material is somewhat uncertain in the case of manual paper feeding, etc., and also detects sheet materials that have failed to be fed and transported. An object of the present invention is to provide a sheet feeding device that prevents accidents such as poor separation by stopping the copying operation.

Embodiments of the present invention will be described in detail below with reference to the drawings.

In the embodiment, a case will be described in which paper is used as a sheet material, which is a paper feeding device of an electronic copying apparatus as shown in FIG.

FIG. 1 is a perspective view mainly showing the transfer position and separation mechanism. Around the photosensitive drum l having a photosensitive layer therearound, a corona discharger serving as a means for forming a latent image, an optical system for exposure, and a developing device (not shown) serving as a means for developing the formed latent image are successively installed. The photosensitive drum 1 is placed at a predetermined position along the rotational direction of the arrow.

A diagonal feeding means is provided on the conveyance path 3 of the transfer paper λ past a paper feed roller (not shown).

As shown in FIG.
The drive roller 3 is provided with the top surface of the drive roller 3 slightly peeking through the hole 6 for the drive roller 3, and is rotated in the direction of the arrow by a drive means (not shown). At the center of the top of the drive roller 5 is a drive roller! A driven ball 7 that is pressed against the drive roller S by its own weight and rotates as a result of the drive roller S is held in a fixed housing l. Drive roller! The traveling direction of the upper surface of the transfer paper is a direction B slightly to the left of the normal moving direction A of the transfer paper.

A paper guide is provided on the left side of the transfer paper conveyance path 3,
The front end of the paper guide 9 and the pair of feed rollers i provided next
o, at a position within a separation width from the left end of the conveyance path 3,
A paper detection switch // having a contact seen from the lower surface to the upper surface of the conveyance path is fixed.

A separating means is provided opposite to the left end of the photosensitive drum. Separating means/J is a separating guide/3 made of, for example, a thin metal or polyester film, one end of which is fixed above the conveying path 3 and extends in the direction of movement of the transfer paper.
The tension spring l! comes into contact with the left end of the l! is fixed at the bottom edge of the The separation means are not limited to the above,
A separation claw or the like may also be used.

The distance between the right side of the separating guide 7.2 and the paper guide bar is the above-mentioned separating width.

Further, a corona discharger 6 is provided downstream of the developing device in the rotational direction of the photosensitive drum 2, adjacent to the photosensitive drum 1 between the feed roller pair IO and the separation means lλ.

When the copying operation starts, the photosensitive drum / rotates in the direction of the arrow, and the latent image formed by the exposure optical system is developed by the developing device.

On the other hand, the transfer paper fed by the paper feed roller moves along the conveyance path 3 in the direction of arrow A, and if the transfer paper is not moving along the paper guide.

The driving roller is sandwiched between the driving roller 3 and the driven ball and is moving! Then, it moves to the left side by the driven ball and moves forward (ie, in the direction of arrow B) until it becomes one paper guide.

Next, when the paper detection switch // comes into contact with the transfer paper, the paper detection switch // continues the copying operation by a control means (not shown), but when the transfer paper comes into contact with the paper detection switch If not, the control means stops the electronic reproduction device.

When the transfer paper comes into contact with the paper detection switch IT and the copying operation continues, the leading edge of the transfer paper reaches the feed roller pair 10, and the position of the rotating photosensitive drum l and the developer are synchronized.
Moving further, the developer particles being developed on the photosensitive drum 1 are charged with an opposite polarity by the corona discharger 16, and the developer particles are transferred to the transfer paper 3@, and the transfer process is completed. After that, the transfer paper λ is separated from the photosensitive drum 1 by the separating means 12, and the transfer paper λ is separated from the photosensitive drum 1, and is delivered to a fixing device (not shown).

On the other hand, the developer remaining on the photosensitive drum l during the transfer is removed by a cleaning means.

Although the case where sheet materials are manually fed into an electronic copying apparatus has been described above, excellent results can also be obtained in an electronic copying apparatus in which sheets are automatically fed from a paper feeder.

As described above, the present invention provides an image forming apparatus having a separating means at the side end of a photosensitive drum, in which the position of the sheet material is regulated along the sheet material transport direction upstream of the sheet material transport path from the separating means. A sheet material guide, a diagonal conveying means disposed upstream of the sheet material guide and conveying the sheet material in a direction along the sheet material guide, and an iron material located between the sheet material guide and the separating means. Since it has a sheet material detection means disposed upstream of the sheet material conveyance path of the separation means and a control means for controlling the image forming apparatus based on a signal from the detection means, manual paper feeding guidance is somewhat uncertain. Even if the manual feed guide is poor and the paper feed cannot be corrected to the proper transfer paper conveyance path, the electronic copying device stops working and prevents jams from occurring. . Further, in order to normalize the paper feeding guide, it is possible to prevent the transferred image from shifting with respect to one sheet of transfer paper.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the present invention, and Fig. 1 is an enlarged cross-sectional side view showing the diagonal feeding means. 3. Drive roller 6. - Hole Φ - Driven ball 9. Paper guide io.. Feeding roller pair //-. Paper detection switch l
, Co. Separation means. Patent applicant: Canon Co., Ltd. Agent: Part Arai

Claims (1)

[Claims] l In an image forming apparatus having a separating means at a side end of a photosensitive drum, a sheet material guide for regulating the position of the sheet material along the sheet material conveying direction is provided upstream of the sheet material conveying path from the separating means, and the sheet material guide. a diagonal conveying means disposed upstream of the sheet material guide and conveying the sheet material in a direction along the sheet material guide; and a diagonal conveying means disposed between the sheet material guide and the separation means to convey the sheet material of the nuclear separation means. A sheet material feeding device for an image forming apparatus, which includes a sheet material detecting means arranged upstream of a path, and a control means for controlling the image forming apparatus based on a signal from the detecting means.