JP2001230900A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device that can discriminate a side of paper not in use and forms an image thereon even when front sides and rear sides of paper sheets whose one side is formed with an image are placed at random. SOLUTION: In facsimile equipment 1, recoding paper sheets 20 only on the one side of which an image is formed are set in a paper feed cassette or the like and the recording paper sheets 20 are carried one by one from the paper feed cassette or the like to a plotter 6 through a carrying path. When a detection section 6 of the plotter 6 detects a detected side being the lower side of the recording paper sheet 20 in a plotter 6 carried through the carrying path 21 and a main control section discriminates that the detected side of the recording paper sheet 20 is a white side, the main control section drives a lower side recording section 22 of the plotter 9 to allow the lower side recording section 22 to record an image on the lower side being the detected side of the recording paper 20. When the main control section 2 discriminates that the detected face of the destination paper 20 is a side having already been used, the main control section 2 drives an upper side recording section 23 of the plotter 9 via an image input output control section 8 to allow the upper side recording section 23 to record an image on the upper side being a non-detection side of the recording paper 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus in which an unused surface of an image is properly formed even when a single-sided used paper having an image formed on one side is placed upside down. The present invention relates to an image forming apparatus that forms an image by determining.

[0002]

2. Description of the Related Art Conventionally, in order to protect forest resources and to make effective use of resources, image forming apparatuses such as printers, copiers and facsimile machines use single-sided used paper on which an image is formed on one side. An image is formed on an unused surface on which no image is formed.

In this case, the operator of the image forming apparatus has
The single-sided used paper is set in the paper feed cassette of the image forming apparatus so that the image forming surface (used surface) of the single-sided used paper is aligned and an image is formed only on the unused surface.

However, when the image forming surfaces are aligned or set in the paper feed cassette of the image forming apparatus, a human error may occur in which some or all of the single-sided used paper is turned upside down. In addition, aligning the front and back surfaces of the single-sided used paper is a troublesome operation.

In such a case, the image is formed in a state in which the image is overwritten on the already used surface of the single-sided used paper on which the image has been already formed. Check that the image is properly formed on the unused side of the used paper.
It is necessary to check the front and back of the used paper on one side of the paper feed cassette, and to form an image again, which has been a problem that it is complicated.

Therefore, various proposals have conventionally been made to solve this problem. For example, a printing unit that can print a mark at a predetermined position on the recording paper at the same time as printing the image information on the recording paper, a supply unit that accommodates a plurality of recording papers, and that can supply the recording paper to the printing unit, Detecting means for detecting a mark on the recording paper set in the supply means, and discharging the recording paper based on the detection information of the detecting means before performing an operation of printing image information on the recording paper. A facsimile apparatus comprising a paper discharge control means (Japanese Patent Laid-Open No. Hei 5-3084).
63).

That is, this conventional facsimile apparatus adds a mark when printing on a new recording paper, and determines whether or not the recording paper conveyed to the printing section has a mark on the recording surface of the recording paper. It is an object of the present invention to detect whether or not the recording sheet is a recording surface and, if the recording surface is a recorded surface, discharge the recording sheet without printing on the recording sheet and secure appropriate recording.

[0008] Further, the present applicant firstly reads out a recording image on one side of a placed transmission original and transmits it to the other party, and records and outputs a received image on one side of recording paper. Facsimile machine having a recording means
Transmitted document storing means for storing the transmitted document after transmission of the recorded image in the apparatus, and back paper recording means for recording and outputting the received image on the back of the stored transmitted document. (See Japanese Patent Application Laid-Open No. 7-15584).

That is, this facsimile apparatus stores a transmitted original in the apparatus, records an image on the back side of the transmitted original, which is a blank sheet, and effectively uses the transmitted original as a backing sheet without any trouble. It is intended to be.

[0010]

However, in the facsimile apparatus described in Japanese Patent Laid-Open No. Hei 5-308463, a mark is added when printing on new recording paper.
It is detected whether or not the recording surface of the recording paper is a recorded surface by detecting whether or not a mark is given to the recording paper conveyed to the printing unit, and if the recording surface is the recorded surface, printing is performed on the recording paper. Since the recording paper is ejected without recording, the condition is that the recording paper that has been recorded on one side is recorded by the facsimile apparatus and is marked, and recording is performed by an unspecified number of image forming apparatuses. This method cannot be applied to the case where recording is appropriately performed on the non-recording surface of recording paper on which single-side recording has been performed, and there has been a problem that the usability is poor.

Also, in the facsimile apparatus described in Japanese Patent Application Laid-Open No. Hei 7-15584, a transmitted original is stored in the apparatus and an image is recorded on the back side of a blank white sheet of the transmitted original. Although it is possible to reuse the used original, it is not applicable when recording is properly performed on the unused side of single-sided used paper recorded by an unspecified number of image forming apparatuses. There was a problem of poor sex.

Therefore, according to a first aspect of the present invention, there is provided a method for forming an image on one side of a single-sided used sheet in an image forming section.
And a second image forming unit that forms an image on the other side of the single-sided used paper, and which one of the single-sided used paper conveyed from the paper feeding unit to the image forming unit is unused. The first image forming unit and the second image forming unit are selectively driven based on the detection result to determine which one of the used surfaces is the used surface. By forming an image on the used side, even if the user sets the used single-sided paper in the paper feed unit without being aware of the unused side and the used side, the single-sided use recorded by the specific image forming apparatus Without being limited to the used paper, the unused side and the used side of the single-sided used paper set in the paper feed unit are detected in a state where the unused side and the used side are not aligned, and two images are detected. An image forming apparatus that forms an image on an unused surface of a single-sided used paper on one side of a forming unit and has good usability. It is an object of the present invention to provide.

According to a second aspect of the present invention, there is provided a double-sided recording function for forming an image on an image forming section on a different side of the single-side used surface according to a conveyance path on which the single-side used paper is conveyed from the sheet feeding section. A transport path switching for switching the transport path of the single-sided used paper conveyed from the paper supply section to the image forming section to a transport path in which the image forming section forms an image on a different side of the single-sided used side. Means for detecting which of the single-sided used paper conveyed from the paper supply unit to the image forming unit is an unused surface and which is a used surface, and based on the detection result, a conveyance path switching unit. By controlling the switching operation of the conveyance path and the operation of the image forming unit to form an image on the unused side of the single-sided used paper in the image forming unit, the user can use the single-sided used paper as the unused side and the used side. To the paper feed unit without having to worry about The single-sided used paper set in the paper feed unit with the unused side and the used side not aligned is not limited to the single-sided used paper recorded by the specific image forming apparatus. Detect unused and used surfaces of
An object of the present invention is to provide an inexpensive image forming apparatus with good usability by forming an image on an unused surface of a single-sided used paper by one image forming unit.

According to a third aspect of the present invention, one of the single-sided used papers to be conveyed next to the single-sided used paper to be conveyed among the single-sided used papers placed on the paper feeder is used as a detection surface. Whether or not the surface is detected by the detection means, based on the detection result,
A normal conveyance unit that conveys single-sided used paper to the image forming unit in a state where the detection surface of the detection unit from the paper supply unit is the image forming surface in the image forming unit, and reverses the single-sided used paper from the paper supply unit. In the state where the surface opposite to the detection surface of the detection means is the image forming surface in the image forming unit, one of the reversing conveyance means for conveying to the image forming unit is driven so that the unused surface of the single-sided used paper is The image forming unit conveys the image forming surface and forms the image in the image forming unit. By simply providing the detecting unit and the reversing conveying unit in the normal image forming apparatus, the user can use the single-sided used paper. Even if you set the unused side and the used side in the paper feeding unit without being conscious of it, the unused side and the used side are not limited to the single-sided used paper recorded by the specific image forming apparatus. Single-sided used paper set in the paper feed unit with misaligned By detecting the unused surface and already spent surface,
It is an object of the present invention to provide an image forming apparatus that forms an image on an unused surface of a single-sided used paper by one image forming unit and has good usability and is inexpensive.

[0015]

According to an aspect of the present invention, there is provided an image forming apparatus which conveys single-sided used paper from a paper feeding unit to an image forming unit and forms an image in the image forming unit. A first image forming unit that forms an image on one side of the single-sided used paper, and a second image forming unit that forms an image on the other side of the single-sided used paper. Detecting means for detecting which of the single-sided used paper conveyed from the paper feeding unit to the image forming unit is an unused surface and which is a used surface, and a detection of the detecting unit Based on the result, the first of the image forming unit
Control means for selectively driving the image forming section and the second image forming section to form an image on an unused surface of the single-sided used paper, thereby achieving the above object. I have.

According to the above arrangement, the first image forming section for forming an image on one side of the single-sided used paper and the second image forming section for forming the image on the other side of the single-sided used paper are formed in the image forming section. An image forming unit, and detects which of the single-sided used paper conveyed from the paper supply unit to the image forming unit is an unused surface and which is a used surface, and based on the detection result, hand,
Since the first image forming unit and the second image forming unit are selectively driven to form an image on the unused surface of the single-sided used paper, the user can change the single-sided used paper to the unused surface and the used surface. Even if the paper is set in the paper feeding unit without being aware of the surface, the paper is not limited to single-sided used paper recorded by a specific image forming apparatus, and is fed in a state where the unused surface and the used surface are not aligned. The unused side and the used side of the single-sided used paper set in the set are detected, and an image can be formed on the unused side of the single-sided used paper in one of the two image forming units. Can be improved.

According to a second aspect of the present invention, there is provided an image forming apparatus in which a single-sided used sheet is conveyed from a paper feeding section to an image forming section and an image is formed in the image forming section. A double-sided recording function for forming an image on a different one of the single-sided used surfaces according to a conveyance path on which the single-sided used paper is conveyed from the paper supply unit, and is conveyed from the paper supply unit. Transport path switching means for switching a transport path of the single-sided used paper to the image forming unit to the transport path on which the image forming unit forms an image on a different surface from the single-sided used surface; and Detecting means for detecting which of the single-sided used paper conveyed to the image forming unit is an unused surface and which is a used surface, and the conveying path switching means based on a detection result of the detecting means Of the transfer route And controls the operation of the image forming section, by providing a control means for causing the image forming unused surface of the one-side spent paper to the image forming section,
The above objective has been achieved.

According to the above configuration, the image forming section has a double-sided recording function of forming an image on a different side of the single-side used surface in accordance with the transport path of the single-side used paper from the paper feeding section. Transport path switching means for switching the transport path of the single-sided used paper conveyed from the paper feeding section to the image forming section to a transport path in which the image forming section forms an image on a different side of the single-sided used surface. And detects which of the single-sided used paper conveyed from the paper feeding unit to the image forming unit is an unused surface and which is a used surface, and based on the detection result, conveys the conveyance path switching unit. By controlling the path switching operation and the operation of the image forming section, the image forming section forms an image on the unused side of the single-sided used paper, so that the user can switch the single-sided used paper to the unused side and the used side. Set it in the paper feed unit without awareness However, without being limited to single-sided used paper recorded by a specific image forming apparatus, the unused side of the single-sided used paper set in the paper feeding unit in a state where the unused side and the used side are not aligned. The used surface can be detected and one image forming unit can form an image on the unused surface of the single-sided used paper, thereby improving usability at low cost.

According to a third aspect of the present invention, there is provided an image forming apparatus, wherein a plurality of single-sided used sheets are conveyed from a paper supply unit to the image forming unit, and a specific surface of the single-sided used sheet is then processed by the image forming unit. In the image forming apparatus that performs image formation with the image forming surface as the image forming surface, the one surface of the single-sided used paper to be conveyed next among the single-sided used papers placed on the paper feeding unit is set as a detection surface. Detecting means for detecting whether or not the detection surface is an unused surface; and transporting the single-sided used paper from the paper feeding unit to the image forming unit in a state where the detection surface becomes the image forming surface in the image forming unit. A normal-conveying unit that reverses the single-sided used paper from the paper supply unit and conveys the used paper to the image forming unit in a state where the surface opposite to the detection surface becomes the image forming surface in the image forming unit. Based on the detection result of the reverse conveyance means and the detection means. Then, one of the forward transport means and the reverse transport means is driven to transport the unused surface of the single-sided used paper in a state where the unused surface becomes an image forming surface in the image forming portion, and the image forming portion forms an image. The above object is achieved by providing a control means for performing the following.

According to the above arrangement, one surface of the single-sided used paper to be conveyed next among the single-sided used papers placed on the sheet feeding unit is set as a detection surface, and whether the detection surface is an unused surface is used. Whether the single-sided used paper is conveyed to the image forming unit in a state where the detection surface of the detecting unit is the image forming surface of the image forming unit from the paper feeding unit based on the detection result. Transfer / conveying means, and a reversing / conveying means for reversing one-sided used paper from the paper feeding unit and conveying the sheet to the image forming unit in a state where the surface opposite to the detection surface of the detection unit is the image forming surface in the image forming unit Either one is driven and the unused surface of the single-sided used paper is conveyed in a state where the unused surface becomes the image forming surface in the image forming unit, and the image is formed in the image forming unit. By simply providing a reversing conveyance means, the user can convert one-sided used paper to the unused side. Even if the used side is set in the paper feeder without being aware of it, the unused side and the used side are not aligned without being limited to single-sided used paper recorded by a specific image forming apparatus. , The unused side and the used side of the single-sided used paper set in the paper feeding unit can be detected, and one image forming unit can form an image on the unused side of the single-sided used paper. Usability can be improved at low cost.

[0021]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 and 2 show a first embodiment of the image forming apparatus according to the present invention. This embodiment corresponds to claim 1 of the present invention.

FIG. 1 is a block diagram of a facsimile machine 1 to which an image forming apparatus according to a first embodiment of the present invention is applied.

In FIG. 1, a facsimile apparatus 1 includes a main control unit 2, an operation control unit 3, a main memory 4, an image memory 5,
Detecting unit 6, communication / line control unit 7, image input / output control unit 8,
Plotter 9, scanner 10 and hard disk drive (H
D) 11 and the like, and the above components are connected by a bus 12.

The main memory 4 has a ROM (Read Only Memory).
y) and RAM (Random Access Memory)
The ROM stores various programs such as a basic processing program of the facsimile apparatus 1 and a recording control processing program to be described later, and also stores various data and system data necessary for executing these various programs. I have.

The main control unit (control means) 2 mainly includes a CPU
(Central Processing Unit) and the main memory 4
Of the main memory 4 based on the program in the ROM
Facsimile machine 1 using M as a work memory
And executes the basic processing as the facsimile machine 1 and the recording control processing described later.

An operation display unit (not shown) is connected to the operation control unit 3. The operation display unit is necessary for operating the facsimile apparatus 1 such as a ten-key, a start key, a function key, a one-touch dial key, and a speed dial key. In addition to various operation keys, a display (for example, a liquid crystal display) is provided, and various commands such as a transmission operation are input from the operation keys. Various information to be notified to the operator is displayed.

The image memory 5 is composed of a readable / writable memory such as a large-capacity RAM, and mainly stores image information for transmission and received image information. The image information in the image memory 5 is managed by the main control unit 2 and is read out at a predetermined time to perform a transmission process, a recording process on recording paper by the plotter 9, and the like.

The communication / line control unit 7 includes a line L, for example, a PSTN (Public Switched Telephone Network) or an ISDN (Integrated Service).
s Digital Network (service digital network) is connected, and the communication / line control unit 7 automatically receives an incoming call from the line L and performs an automatic call processing to the line L. The communication / line control unit 7 operates under the control of the main control unit 2 to exchange G3 and G4 facsimile control signals with the other party's facsimile machine, and to execute G3 and G4 facsimile communication procedures. .

A plotter 9 and a scanner 10 are connected to the image input / output control unit 8, and operate under the control of the main control unit 2 to control the operations of the plotter 9 and the scanner 10. The image input / output control unit 8 includes an image processing circuit and the like, compresses image data read by the scanner 10 by a predetermined compression method, and sends the image data to the image memory 5 or the hard disk device 11 or the communication / line control unit 7. Output. Further, the image input / output control unit 8 expands (decodes) the image data input from the image memory 5, the hard disk device 11, or the communication / line control unit 7 and outputs the image data to the plotter 9. The plotter 9 records and outputs an image on a recording paper 20 based on image data that is expanded and input by an image processing circuit of the image input / output control unit 8. Further, the image input / output control unit 8 performs left / right inversion processing, up / down inversion processing, scaling processing, and the like of the image in the image processing circuit.

As shown in FIG. 2, the plotter 9 records an image on the lower surface (the lower surface in FIG. 2) of the recording paper 20 conveyed through a conveying path 21 from a paper cassette (not shown) or the like. A recording unit 20 for recording an image on the upper surface (upper surface in FIG. 2) of the recording paper 20. The lower recording unit 22 and the upper recording unit 23 are, for example, electrophotographic recording. The device is being used. The lower surface recording section 2
2 and the upper surface recording unit 23 function as a first image forming unit and a second image forming unit.

The lower recording unit 22 transfers the toner image on the photoconductor 22a to the recording paper 20 on a photoconductor 22a which is disposed below the conveyance position of the recording paper 20 and is driven to rotate clockwise. The roller 22b is provided in a state of contact with the roller 22b. The lower surface recording unit 22 uniformly charges the photoconductor 22a by a charging unit (not shown), and then irradiates the photoconductor 22a with writing light modulated by image data to form an electrostatic latent image. The electrostatic latent image is developed by attaching toner to the photoreceptor 22a on which the electrostatic latent image has been formed, and the toner image on the photoreceptor 22a is transferred to the lower surface of the recording paper 20 to form a toner image on the lower surface of the recording paper 20. To form

The upper surface recording section 23 applies the toner image on the photoconductor 23a to the photoconductor 23a, which is disposed above the conveying position of the recording paper 20 and is driven to rotate counterclockwise.
The transfer roller 23b for transferring the image to the printer is provided in a state of contact with the transfer roller 23b. The upper surface recording unit 23 uniformly charges the photosensitive member 23a by a charging unit (not shown), and then irradiates the photosensitive member 23a with writing light modulated by image data to form an electrostatic latent image. The electrostatic latent image is developed by attaching toner to the photoreceptor 23a on which the electrostatic latent image has been formed, and the toner image on the photoreceptor 23a is transferred to the upper surface of the recording paper 20 to form a toner image on the recording paper 20. To form

The detecting section (detecting means) 6 is arranged such that the lower surface recording section 22 and the upper surface recording section 23 of the plotter 9 use the surface serving as the lower surface of the recording paper 20 as a detection surface in the transport path 21 of the plotter 9. It is arranged so as to detect whether it is white (unused surface) or not. As the detection unit 6, for example, a contact image sensor with a light source capable of detecting one or more lines is used. The detection unit 6 using the contact image sensor scans the detection surface, which is the lower surface of the recording paper 20 conveyed along the conveyance path 21, over the entire surface of the recording paper 20 and determines whether the detection surface is an unused surface or a used surface. And outputs the detection result to the main control unit 2.

The main control unit 2 determines whether the lower surface of the recording paper 20 is a blank surface or an image-formed surface (used surface) by outputting a signal from the contact image sensor or the like as the detection unit 6. The determination is made by comparing with a threshold level previously evaluated for the white (unused) recording paper 20. Note that this threshold level is appropriately set by evaluating so as not to make an erroneous determination due to irregularities of the recording paper 20 or the like.

Referring again to FIG. 1, the scanner 10 uses, for example, an image scanner using a CCD (Charge Coupled Device), and generally has an ADF (automatic document feeder). The ADF feeds the set plurality of documents one by one to a document reading position of the scanner 10, and the scanner 10 scans the document conveyed from the ADF and reads an image of the document at a predetermined resolution. .

The hard disk device 11 has a predetermined large capacity, and has registration information necessary for the operation of the facsimile device 1;
It stores communication information, output information, image data of a transmission original read by the scanner 10, received image data, and the like.

Next, the operation of the present embodiment will be described. In the facsimile apparatus 1 of the present embodiment, the plotter 6 is provided with a lower surface recording unit 22 and an upper surface recording unit 23 that can selectively record images on both the upper and lower surfaces of the recording paper 20, and the recording conveyed to the plotter 6. The detecting unit 6 detects which surface of the paper 20 is the used surface and which surface is the blank surface (unused surface), and forms an image on the blank surface based on the detection result. There is a characteristic in what we do.

That is, in the facsimile machine 1, a plurality of recording papers (single-side used paper) 20 used for image formation on only one side are placed on a paper cassette or the like (not shown), and one sheet at a time from the paper cassette or the like. The recording paper 20 is transported to the plotter 6 through the transport path 21.

The detecting section 6 detects the lower surface of the recording paper 20 conveyed through the conveying path 21 by the plotter 6 and detects the lower surface.
The detection signal is output to the main control unit 2, and the main control unit 2 determines whether the detection surface of the recording paper 20 is a blank surface (unused surface) based on the detection signal from the detection unit 6.

When the main control unit 2 determines that the detection surface of the recording paper 20 is blank, it drives the lower recording unit 22 of the plotter 9 via the image input / output control unit 8, and the lower recording unit 22 controls the recording paper. An image is recorded on the lower surface, which is the detection surface 20.

When the main control unit 2 determines that the detection surface of the recording paper 20 is a used surface, the image input / output control unit 8
The upper surface recording unit 23 of the plotter 9 is driven via the, and the upper surface recording unit 23 records an image on the upper surface, which is the non-detection surface of the recording paper 20.

As described above, the facsimile apparatus 1 of the present embodiment has the lower surface (detection surface) of the recording paper 20 sent out from a paper cassette or the like on which a plurality of single-sided used recording papers 20 are placed. Is an unused surface (blank surface) or a used surface, and the detecting unit 6 selects one of the lower surface recording unit 22 and the upper surface recording unit 23 of the plotter 6 based on the detection result. The image is recorded on an unused surface of the recording paper 20 by using the image forming apparatus.

Therefore, even when the single-sided used recording paper 20 is placed in a paper feed cassette or the like in a state where the unused surface and the used surface are not aligned, the unused surface of the recording paper 20 is not changed. The facsimile machine 1 can appropriately determine and automatically form an image on an unused surface of the recording paper 20, eliminating the need for the user to check the front and back of the recording paper 20 and perform re-recording. Usability can be improved.

FIG. 3 is a diagram showing a second embodiment of the image forming apparatus according to the present invention. In this embodiment, recording is performed based on a determination result of an unused surface of a recording sheet. The image recording is performed on an unused surface of the recording paper by one image recording section by switching the paper transport path, and corresponds to claim 2.

This embodiment is applied to a facsimile machine similar to that of the first embodiment.
In the description of the present embodiment, the description will be made by using the reference numerals used in the above-described first embodiment as needed.

FIG. 3 shows a plotter 3 of a facsimile apparatus 30 to which the image forming apparatus according to the second embodiment of the present invention is applied.
It is a schematic structure front view of one part.

The plotter 31 switches between the lower surface of the recording paper 20 (the lower surface in FIG. 3) and the upper surface of the recording paper 20 which are conveyed through a conveying path 32 from a paper feed cassette or the like (not shown). The recording unit 33 is provided. For the double-sided recording unit 33, for example, an electrophotographic recording device is used.

The double-sided recording section 33 includes a photoconductor 3 that is rotated and driven in a clockwise and counterclockwise direction.
The upper transfer roller 35 and the lower transfer roller 36 that transfer the toner image on the recording paper 20 onto the recording paper 20 are disposed in contact with each other. When the recording paper 20 is conveyed between the upper transfer roller 35 and the recording paper 20, the photoconductor 34 rotates clockwise to transfer the toner image formed on the photoconductor 34 to the upper transfer roller 35. Is transferred to the lower surface of the recording paper 20 to form a toner image on the recording paper 20. Further, the double-sided recording unit 33 is configured such that the recording paper 20 is
6, the photosensitive member 34 rotates in a counterclockwise direction, and the toner image formed on the photosensitive member 34 is transferred onto the upper surface of the recording paper 20 by the lower transfer roller 36 to form a toner image. Is formed on the recording paper 20.

The plotter 31 has an upper transport path (transport path) 37 for transporting the recording paper 20 between the photosensitive member 34 and the upper transfer roller 35, and the photosensitive member 34 and the lower transfer roller 3.
A lower transport path (transport path) 38 for transporting the recording paper 20 is provided between the upper transport path 37 and the lower transport path 38.
A distribution valve 39 is provided at the branch.

The distribution valve (transportation path switching means) 39
Operating under the control of the system controller 2, the transport path 32 is selectively communicated with the upper transport path 37 and the lower transport path 38, and the transport path of the recording paper 20 transported through the transport path 32 is changed to the upper transport path. 37 and the lower conveyance path 38.

A detection section 40 is provided in the conveyance path 32. The detection section (detection means) 40 uses the double-sided recording section 33 of the plotter 31 as a detection surface, which is the lower surface of the recording paper 20. It is arranged in a state of detecting whether or not the detection surface is a blank paper surface (unused surface). The detection unit 40 is the same as the detection unit 6 of the first embodiment, and uses, for example, a contact image sensor with a light source that can detect one or more lines. Detection unit 4 using contact image sensor
0, the detection surface, which is the lower surface of the recording paper 20 conveyed along the conveyance path 32, is scanned over the entire surface of the recording paper 20 to detect whether the detection surface is an unused surface, and the detection result is sent to the main control unit 2. Output.

The main control unit 2 determines whether the lower surface of the recording paper 20 is a blank surface (unused surface) or an image-formed surface (used surface) by the contact image sensor, which is the detection unit 40. And the like and the threshold level previously evaluated for the white (unused) recording paper 20 is determined. In addition,
The threshold level is appropriately set by evaluating so as not to make an erroneous determination due to the unevenness of the recording paper 20 or the like.

Next, the operation of the present embodiment will be described. In the facsimile apparatus 30 of the present embodiment, the plotter 31 is provided with a double-sided recording section 33 capable of selectively recording an image on both the upper and lower surfaces of the recording paper 20, and any of the recording papers 20 conveyed to the plotter 31. The feature is that the detection unit 40 detects which surface is a used surface and which surface is a blank surface, and forms an image on a blank surface (unused surface) based on the detection result. There is.

That is, in the facsimile machine 30, a plurality of recording papers 20 used for image formation on only one side are placed on a paper cassette or the like (not shown), and one sheet is fed from the paper cassette or the like.
The recording paper 20 is conveyed to the plotter 31 through the conveyance path 32 sheet by sheet.

A detection surface serving as a lower surface of the plotter 31 of the recording paper 20 conveyed through the conveyance path 32 is detected by the detection unit 40, and a detection signal is output to the main control unit 2. Based on the detection signal from the unit 40, it is determined whether the detection surface of the recording paper 20 is a blank surface (unused surface).

When the main control unit 2 determines that the detection surface of the recording paper 20 is blank, the main control unit 2 drives the distribution valve 39 upward to make the transport path 32 communicate with the upper transport path 37, and through the upper transport path 37. The recording paper 20 is transferred to the photosensitive member 3
4 and the upper transfer roller 35,
The photoconductor 34 is driven to rotate clockwise.

The double-sided recording unit 33 moves the recording paper 20 between the photosensitive member 34 and the upper transfer roller 35 through the upper conveyance path 37.
Is conveyed, the toner image formed on the photoreceptor 34 rotating clockwise is transferred to the unused lower surface of the recording paper 20 by the upper transfer roller 35, and the toner image is transferred onto the recording paper 20. Form.

When the main control unit 2 determines that the detection surface of the recording paper 20 is the used surface, it drives the distribution valve 39 downward to make the transport path 32 communicate with the lower transport path 38. The recording paper 20 is transferred to the double-sided recording unit 3
The photoconductor 34 is conveyed between the third photoconductor 34 and the lower transfer roller 36, and the photoconductor 34 is rotated counterclockwise.

The double-sided recording section 33 moves the recording paper 20 between the photoreceptor 34 and the lower transfer roller 36 through the lower conveying path 38.
Is conveyed, the photoconductor 34 rotates counterclockwise.
The toner image formed on the recording paper 20 is transferred to the unused upper surface of the recording paper 20 by the lower transfer roller 36 to form a toner image on the recording paper 20.

As described above, the facsimile apparatus 30 according to the present embodiment has the lower surface (detection surface) of the recording paper 20 sent out from a paper cassette or the like on which a plurality of single-sided used recording papers 20 are placed. Is detected by the detection unit 40 as to whether it is an unused surface (blank surface) or a used surface, and based on the detection result, the distribution valve 39 is driven so that the photosensitive member 34 of the duplex recording unit 33 The recording paper 20 is conveyed between any one of the upper transfer roller 35 and the lower transfer roller 36 that comes into contact, and an image is recorded on an unused surface of the recording paper 20.

Therefore, even when the single-sided used recording paper 20 is placed on a paper feed cassette or the like in a state where the unused surface and the used surface are not aligned, the unused surface of the recording paper 20 is not changed. The facsimile machine 30 can appropriately determine and automatically form an image on an unused surface of the recording paper 20, eliminating the need for the user to check the front and back of the recording paper 20 and perform re-recording. Usability can be improved.

FIGS. 4 and 5 are views showing a third embodiment of the image forming apparatus according to the present invention. In this embodiment, a plurality of recording sheets stored in a recording sheet cassette are removed. Of the recording paper conveyed next to the plotter, it is determined in the recording paper cassette which unused surface is to be used, and based on the result of the determination, the recording paper is conveyed as it is or inverted, and one paper is conveyed. The image recording section records an image on an unused surface of the recording paper, and corresponds to claim 3.

This embodiment is applied to a facsimile machine similar to that of the first embodiment.
In the description of the present embodiment, the description will be made by using the reference numerals used in the above-described first embodiment as needed.

FIGS. 4 and 5 are schematic front views of a sheet feeding mechanism 51 of a facsimile apparatus 50 to which the image forming apparatus according to the third embodiment of the present invention is applied.

4 and 5, the paper feeding mechanism 51 of the facsimile apparatus 50 includes a recording paper cassette 52, a normal rotation paper feeding section 53, a reversing paper feeding section 54, a detection section 55, and the like. A plurality of single-sided used recording papers 20 are stored in 52.

The forward rotation paper feeding section (forward rotation transporting means) 53 is disposed near one end of the recording paper 20 in the recording paper cassette 52, and feeds the uppermost recording paper 20 in the recording paper cassette 52. 1
A sheet feed roller 56 that separates the sheets one by one and sends the sheet to a plotter (not shown);
The paper feed roller 56 is rotated clockwise to separate the uppermost recording paper 20 in the recording paper cassette 52 one by one and guided by the guide plate 57 as it is. And sends it to a plotter (not shown).

The reversing sheet feeding section (reversing and conveying means) 54 is disposed near the other end of the recording sheet 20 in the recording sheet cassette 52, and stores the uppermost recording sheet 20 in the recording sheet cassette 52 in one.
A paper feed roller 58 that separates each sheet and sends it to a plotter (not shown);
The sheet feed roller 58 is provided with a reversing guide plate 59 that guides the recording paper 20 while reversing 0, a conveyance guide plate 60 that conveys the reversed recording paper 20 in the plotter direction, and the like. The uppermost recording paper 20 in the cassette 52 is separated one by one, and the recording paper 20 is reversed by a reversing guide plate 59, and the recording paper 20 is reversed by a plotter (not shown) while being guided by a conveyance guide plate 60. And send it out.

The detecting section (detecting means) 55 is attached to the lower surface of the reversing guide plate 59, and the upper surface of the recording paper 20 to be transported next is used as a detecting surface, and the detecting surface is a blank surface (unused surface). It is arranged in a state of detecting whether or not. As the detection unit 55, for example, a CCD (Charge Coupled Dev
A device that detects the entire detection surface of the recording paper 20, such as ice), detects whether the detection surface is an unused surface or not, and outputs the detection result to the main control unit 2.

The plotter (image forming section) of the present embodiment
Is a plotter used in a normal facsimile machine, and forms an image on a specific surface of the recording paper 20 (the upper surface in the recording paper cassette 52).

Next, the operation of the present embodiment will be described. In the facsimile apparatus 50 of the present embodiment, the top surface of the recording paper 20 sent out to the plotter next among the recording papers 20 stored in the recording paper cassette 52 has a blank surface (unused surface).
Is detected by the detection unit 55, and based on the detection result, the recording paper 20 is sent out as it is by the normal rotation paper supply unit 53 or inverted by the reverse paper supply unit 54, and The feature is that the recording paper 20 is sent out such that the recording paper becomes the recording surface of the plotter.

That is, in the facsimile apparatus 50, a plurality of recording papers 20 used for image formation on only one side are stored in a paper feeding cassette 52, and among the recording papers 20 in the recording paper cassette 52, Then, the detection unit 55 detects whether or not the upper surface of the next uppermost recording sheet 20 to be sent out is blank (unused surface). The upper surface of the recording paper 20 is a recording surface on a plotter.

When the main control unit 2 determines that the upper surface (detection surface) of the recording paper 20 is a blank paper surface, it drives the normal rotation paper supply unit 53 and controls the paper supply roller 56 as shown in FIG. By rotating clockwise, the uppermost recording paper 20 in the recording paper cassette 52 is separated one by one, and
And send it out to a plotter (not shown).

When the main control unit 2 determines that the upper surface (detection surface) of the recording paper 20 is a used surface, it drives the reversing paper supply unit 54 as shown in FIG. 58
Is rotated in the counterclockwise direction to separate the uppermost recording paper 20 in the recording paper cassette 52 one by one.
Then, the recording paper 20 is turned upside down and sent out to a plotter (not shown) in an inverted state while being guided by the conveyance guide plate 60.

As described above, the facsimile apparatus 50 of the present embodiment has the upper surface (detection) of the recording paper 20 to be sent out next in the paper supply cassette 52 in which a plurality of used single-sided recording papers 20 are placed. Surface) is detected by the detecting unit 55 whether it is an unused surface (blank surface) or a used surface, and based on the detection result, one of the normal rotation paper feeding unit 53 and the reverse paper feeding unit 54 is detected. Is driven to send the recording paper 20 to the plotter as it is or inverted, and the recording paper 20 is conveyed so that the blank surface of the recording paper 20 becomes the recording surface of the plotter.

Therefore, even when the single-sided used recording paper 20 is placed on a paper feed cassette or the like in a state where the unused surface and the used surface are not aligned, the unused surface of the recording paper 20 is not changed. An appropriate determination can be made and an image can be automatically formed on an unused surface of the recording paper 20. This eliminates the need for the user to check the front and back sides of the recording paper 20 and to perform re-recording, and the like. Usability can be improved.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the present invention is not limited to the above-described embodiment, and various modifications may be made without departing from the gist of the invention. It goes without saying that it is possible.

For example, in each of the above-described embodiments, the case of recording an image by an electrophotographic method has been described. However, the present invention can be applied to a thermal transfer method or an ink jet method. In this case, in the above-described second embodiment, the recording paper 2
0 is conveyed and the recording paper 20 is conveyed in the lower conveyance path 38, the left and right sides of the image are reversed. Therefore, it is possible to reverse the control depending on whether the recording direction of the recording head is recorded up or down. Can respond.

In each of the above embodiments, the case where the present invention is applied to a facsimile machine has been described. However, the image forming apparatus is not limited to the facsimile machine, but is similarly applied to a copying machine, a printer, and the like. be able to.

[0080]

According to the image forming apparatus of the present invention, the first image forming unit for forming an image on one side of the single-sided used paper and the one-sided used paper for the single-sided used paper are provided in the image forming unit. A second image forming unit that forms an image on the other surface, and which one of the single-sided used paper conveyed from the paper supply unit to the image forming unit is an unused surface and which is a used surface And the first image forming section and the second
The image forming section is selectively driven to form an image on the unused side of the single-sided used paper, so that the user can feed the single-sided used paper without paying attention to the unused side and the used side. Is not limited to single-sided used paper recorded by a specific image forming apparatus, and single-sided used paper set in the paper feed unit with unused and used The unused surface and the used surface can be detected, and an image can be formed on the unused surface of one-side used paper in one of the two image forming units, thereby improving usability.

According to the image forming apparatus of the present invention, the image forming section is formed on a different one of the single-side used surfaces in accordance with the conveyance path on which the single-side used paper is conveyed from the paper feeding section. The image forming unit has a double-sided recording function for forming an image, and the conveyance path of the single-sided used paper conveyed from the paper feeding unit to the image forming unit is formed by the image forming unit on a different side of the single-sided used surface. A conveyance path switching unit for switching to a path, detecting which of the single-sided used paper conveyed from the paper feeding unit to the image forming unit is an unused surface and which is a used surface, and based on the detection result, Then, the operation of switching the transport path of the transport path switching means and the operation of the image forming unit are controlled to form an image on the unused surface of the single-sided used paper in the image forming unit. Be aware of used and used surfaces Even if the paper is set in the paper feeding unit without being used, the paper is not limited to the single-sided used paper recorded by the specific image forming apparatus. The unused side and the used side of the single-sided used paper can be detected, and the image forming unit can form an image on the unused side of the single-sided used paper, thereby improving the usability at a low cost. .

According to the image forming apparatus of the present invention, the one surface of the single-sided used paper conveyed next among the single-sided used papers placed on the paper feeding unit is set as the detection surface. The detection unit detects whether the detection surface is an unused surface or not, and based on the detection result, the single-sided used paper in a state where the detection surface of the detection unit by the detection unit becomes the image forming surface in the image forming unit. Forward conveyance means for conveying the paper to the image forming unit, and image formation in a state in which the one-sided used paper is inverted from the paper supply unit and the surface opposite to the detection surface of the detection unit becomes the image forming surface in the image forming unit. Since one of the reversing conveyance means for conveying to the image forming unit is driven to convey the unused surface of the single-sided used paper to be the image forming surface in the image forming unit, and the image is formed in the image forming unit, By simply providing the detection means and the reverse conveyance means in the image forming apparatus of Even if the used paper is set in the paper feeder without paying attention to the unused side and the used side, it is not limited to single-sided used paper recorded by a specific image forming apparatus. The unused side and the used side of the single-sided used paper set in the paper feed unit are detected in a state where the used side and the used side are not aligned, and one image forming unit detects the unused side of the single-sided used paper. An image can be formed, and the usability can be improved more inexpensively.

[Brief description of the drawings]

FIG. 1 is a block diagram of a facsimile apparatus to which an image forming apparatus according to a first embodiment of the present invention is applied.

FIG. 2 is a schematic configuration diagram of a plotter portion of the facsimile apparatus of FIG.

FIG. 3 is a schematic configuration diagram of a plotter portion of a facsimile apparatus to which an image forming apparatus according to a second embodiment of the present invention is applied.

FIG. 4 is a schematic configuration diagram illustrating a state in which a recording sheet is being conveyed by a normal sheet feeding unit of a sheet feeding mechanism of a facsimile apparatus to which a third embodiment of the image forming apparatus according to the present invention is applied.

FIG. 5 is a schematic configuration diagram of a state in which a recording sheet is being conveyed by a reversing sheet feeding unit of the sheet feeding mechanism of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Facsimile apparatus 2 Main control part 3 Operation control part 4 Main memory 5 Image memory 6 Detecting part 7 Communication / line control part 8 Image input / output control part 9 Plotter 10 Scanner 11 Hard disk device 12 Bus 20 Recording paper 21 Transport path 22 Lower surface recording Unit 22a Photoconductor 22b Transfer Roller 23 Upper Recording Unit 23a Photoconductor 23b Transfer Roller 30 Facsimile Device 31 Plotter 32 Transport Path 33 Double-sided Recording Unit 34 Photoconductor 35 Upper Transfer Roller 36 Lower Transfer Roller 37 Upper Transport Path 38 Lower Transport Path 39 Sorting Valve 40 Detector 50 Facsimile machine 51 Paper feed mechanism 52 Recording paper cassette 53 Forward paper feeder 54 Reverse paper feeder 55 Detector 56 Paper feed roller 57 Guide plate 58 Paper feed roller 59 Reverse guide plate 60 Transport guide plate

Claims (3)

[Claims] An image forming apparatus configured to convey a single-sided used sheet from a paper feeding unit to an image forming unit and form an image in the image forming unit; And a second image forming unit for forming an image on the other surface of the single-sided used paper, and the first image forming unit is conveyed from the paper feeding unit to the image forming unit. Detecting means for detecting which one of the single-sided used paper is an unused surface and which is a used surface, and the first image forming section of the image forming section based on a detection result of the detecting means. An image forming apparatus comprising: a control unit configured to selectively drive the first image forming unit and the second image forming unit to form an image on an unused surface of the single-sided used paper. 2. An image forming apparatus according to claim 1, wherein said single-sided used paper is conveyed from said paper supply unit to said image forming unit to form an image in said image forming unit. A double-sided recording function for forming an image on a different side of the single-side used surface according to a conveyance path on which the used paper is conveyed, and the image forming unit for the single-side used paper conveyed from the paper supply unit Transport path switching means for switching the transport path to the transport path for forming an image on a different surface from the one-side used surface in the image forming unit, and the one-sided transported from the paper feeding unit to the image forming unit Detecting means for detecting which of the used paper is the unused surface and which is the used surface, and based on the detection result of the detecting means, the switching operation of the transport path by the transport path switching means and the image forming. Control the operation of the unit An image forming apparatus characterized by comprising a control means for causing the image forming unused surface of the one-side spent paper to the image forming unit. 3. An image for conveying a plurality of single-sided used paper from a paper supply unit to an image forming unit and forming an image on the specific side of the single-sided used paper as an image forming surface in the image forming unit. In the forming apparatus, one surface of the single-sided used paper to be conveyed next among the single-sided used papers placed on the paper feeding unit is used as a detection surface to determine whether the detection surface is an unused surface. Detecting means for detecting, a normal rotation conveying means for conveying the single-sided used paper to the image forming section from the paper feeding section in a state where the detection surface becomes the image forming surface in the image forming section, A reversing conveyance unit for reversing the one-sided used paper from the unit and conveying the sheet to the image forming unit in a state where the surface opposite to the detection surface is the image forming surface in the image forming unit; Based on the result, the forward transport means and the reverse transport Control means for driving one of the steps to convey the unused surface of the single-sided used paper to be an image forming surface in the image forming unit and causing the image forming unit to form an image. An image forming apparatus comprising: