JPH0657647U - Automatic double-sided image forming device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an automatic double-sided image forming apparatus capable of performing double-sided printing on paper without human intervention. A main body 1, a paper feed cassette 2 attached to the main body 1, a manual feed tray 3 formed on the paper feed cassette 2, and a sheet taken from the paper feed cassette 2 into the main body 1. An image forming means 6 for forming an image on the front surface and a back surface of P, a paper discharging means 8 for discharging the paper P on which the image is formed by the image forming means 6 to the outside of the main body 1, and a paper discharging means 8 The paper ejection tray 9 that receives the ejected paper P and a first position that is provided between the paper ejection unit 8 and the paper ejection tray 9 and guides the paper P to the paper ejection tray 9 and the paper P is manually fed. A switching gate 10 for switching between a second position for guiding on the tray 3 and a second position for guiding the paper P having an image formed on its surface to the manual feed tray 3 via the switching gate 10 Take it from the manual feed tray 3 into the main body 1 An automatic double-sided image forming apparatus, characterized in that an image is formed on the back side by the image forming means 6 to perform double-sided image formation.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an automatic double-sided image forming apparatus such as a laser printer.

[0002]

[Prior art]

 In conventional image forming devices such as laser printers, when printing on both sides of the paper, after printing on one side, the printed paper is manually turned inside out and inserted into the bypass tray on the paper cassette. I am printing on the back side.

[0003]

[Problems to be solved by the device]

 However, in such a conventional image forming apparatus, double-sided printing was not possible without human intervention.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an automatic double-sided image forming apparatus that can perform double-sided printing on a sheet without human intervention.

[0005]

[Means for Solving the Problems]

 SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a main body, a paper feed cassette attached to the main body, a manual feed tray formed on the paper feed cassette, and a paper feed cassette incorporated into the main body. Image forming means for forming images on the front and back sides of the formed paper, a paper discharging means for discharging the paper on which the image is formed by the image forming means to the outside of the main body, and a paper discharging means for discharging the paper. A paper output tray that receives paper, and a first position that is provided between the paper output tray and the paper output tray and that guides the paper to the paper output tray and a second position that guides the paper onto the manual paper feed tray. And a switching gate for switching between the front and the back, and guides the paper with an image formed on the front side to the manual feed tray through the switching gate, takes the paper from the manual feed tray into the main body, and transfers it to the back side. Image by image forming means By also in the range, characterized in that to carry out the double-sided image formation formed to.

[0006]

[Action]

 The present invention is configured as described above, and guides the paper on the front surface of which the image is formed by the image forming means to the manual feed tray through the switching gate, takes the paper from the manual feed tray into the main body, and transfers it to the back surface. An image is formed by the image forming means and is discharged to a paper discharge tray, so that double-sided image formation is automatically performed on the paper.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a laser printer as an automatic double-sided image forming apparatus of the present invention. At the right end portion of a main body 1, a detachable paper feed cassette 2 having a large number of paper sheets P stored therein is attached. Has been done. A manual feed tray 3 is integrally formed on the upper surface of the paper feed cassette 2. A paper feed roller 4 is arranged at the leading end position of the paper feed cassette 2 mounted on the main body 1 so as to come into contact with the uppermost paper P of the stored papers. By the rotation of the paper feed roller 4, the paper P is taken into the main body 1 one by one. A transfer drum 6, a fixing roller 7, and a paper discharge roller 8 are sequentially arranged along the paper transport path 5. The transfer drum 6 is made of a photoconductor known in copying machines and facsimiles. Around the transfer drum 6, a charging device, an exposure unit, and a developing device (not shown) are sequentially arranged along the rotation direction thereof.

A paper discharge tray 9 is formed in the upper portion of the main body 1 so as to receive the paper P discharged from the paper discharge roller 8. A switching gate 10 for switching the conveyance direction of the paper P is provided between the paper ejection roller 8 and the leading end position of the paper ejection tray 9. One end of the switching gate 10 is pivotally mounted via a support shaft 10a, and the other end is provided so as to move up and down as a free end 10b. The support shaft 10a of the switching gate 10 is connected to a drive source (not shown), and the drive source rotates the free end 10b up and down.

A turntable 11 is arranged above the main body 1, and a shaft 11a at the center of rotation thereof is connected to a motor via a transmission mechanism (not shown). The left side of the edge of the turntable 11 in the figure faces the paper discharge roller 8 and the switching gate 10. A transport roller 12 is provided on the right upper surface of the edge of the turntable 11 in the figure so as to come into contact with and separate from the turntable 11. That is, when the turntable 11 rotates, the transport roller 12 moves upward to separate from the surface of the turntable 11, and when the paper P is transported onto the turntable 11. Further, the sheet P is further moved downward so as to come into contact with the turntable 11 via the sheet P so as to be conveyed to the destination. A conveyance guide 13 composed of a pair of plates facing each other is arranged between the right edge of the turntable 11 in the drawing and the manual tray 3.

An operation panel (not shown) is provided on the outer surface of the main body 1, and includes a print switch, a numeric keypad for setting the number of prints, a double-sided print mode key for instructing double-sided printing, and an instruction that the document to be copied is vertically written. The vertical writing mode key etc. are arranged.

The operation of the laser printer of the present invention will be described below with reference to the flowchart of FIG. 2 and FIG. Printing is started, and a control unit (not shown) of the main body 1 determines whether or not the operator selects the double-sided printing mode on the operation panel (Step 1). In the case of the single-sided printing mode instead of the double-sided printing mode, the switching gate 10 is conveyed by the drive source (not shown) via the support shaft 10a so as to move the free end 10b of the switching gate 10 in the downward direction, that is, conveyed. The received paper P is set to a position where it is guided to the paper discharge tray 9 (Step 2).

The paper P taken into the main body 1 from the paper feeding cassette 2 by the paper feeding roller 4 is conveyed on the paper conveying path 5. The toner image formed on the transfer drum 6 is first transferred to the paper P conveyed on the conveyance path 5, and then the toner image transferred on the paper 6 is fixed by the fixing roller 7, Single-sided printing is executed (Step 3). Then, the further conveyed sheet P is conveyed on the upper surface of the switching gate 10 by the sheet ejection roller 8 and is ejected to the sheet ejection tray 9 (Step 4), and the one-sided printing is completed.

When the double-sided printing mode is selected in Step 1 above, the switching gate 10 is moved by the drive source (not shown) via the support shaft 10a so as to move the free end 10b of the switching gate 10 upward. The position indicated by the solid line, that is, the position where the conveyed paper P is guided onto the turntable 11 on the bypass side is set (Step 5). At the same time, the transport roller 12 is moved upward and retracted from the turntable 11 (Step 6).

The paper P taken into the main body 1 from the paper feed cassette 2 by the paper feed roller 4 is transported on the paper transport path 5. The toner image formed on the transfer drum 6 is first transferred to the paper P conveyed on the conveyance path 5, and then the toner image transferred on the paper 6 is fixed by the fixing roller 7, Surface printing is executed (Step 7). Then, the further conveyed sheet P is conveyed on the lower surface of the switching gate 10 by the sheet discharge roller 8 and guided onto the turntable 11.

The control unit determines whether or not the vertical writing mode key on the operation panel is operated to select the vertical writing mode (Step 8). Here, when the vertical writing mode is selected, the turntable 11 on which the paper P is placed after the front surface printing is performed is rotated by 180 degrees. That is, the front-back direction of the paper P is switched (Step 9). In the case of horizontal writing, the turntable 11 is not rotated.

At the same time when the 180 ° rotation of the turntable 11 is completed, the transport roller 12 is moved downward to a position where it comes into contact with the paper P, and the rotation of the transport roller 12 causes the paper P to pass through the transport guide 13. It is conveyed and guided to the manual feed tray 3 (Step10). The paper P guided on the manual feed tray 3 is placed on the manual feed tray 3 with the front side having its surface printed facing downward and the back side facing upward. Subsequently, the switching gate 10 is set to the position indicated by the broken line in the figure via the support shaft 10a so as to move the free end 10b thereof downward, that is, the position for guiding the conveyed paper P to the paper discharge tray 9. (Step 11).

The paper P on the manual feed tray 3 with the back side facing upward is taken into the inside of the main body 1 by the rotation of the paper feed roller 4 and is carried on the paper carrying path 5 (Step 12). The toner image formed on the transfer drum 6 is transferred onto the paper P conveyed on the conveyance path 5, and then the toner image transferred onto the paper 6 is fixed by the fixing roller 7. Back surface printing is executed (Step 13). Then, the further conveyed sheet P is conveyed on the upper surface of the switching gate 10 by the sheet discharge roller 8 and is discharged to the sheet discharge tray 9 (Step 4), and the double-sided printing is completed.

[0018]

[Effect of device]

 As described above, according to the present invention, the paper having the image formed on the front surface is once guided to the manual feed tray via the switching gate, the paper is re-loaded from the manual feed tray into the main body, and the image is formed on the rear surface. Since it does, double-sided printing can be performed automatically without human intervention.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a laser printer showing an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the laser printer shown in FIG.

[Explanation of symbols]

 1 ... Main body, 2 ... Paper feed cassette, 3 ... Manual feed tray, 6 ... Transfer drum, 8 ... Paper ejection roller, 9 ... Paper ejection tray, 10 ... Switching gate, 11 ... Turntable.

Claims (1)

[Scope of utility model registration request] 1. A main body, a paper feed cassette mounted on the main body, a manual feed tray formed on the paper feed cassette, and front and back surfaces of sheets taken into the main body from the paper feed cassette. An image forming means for forming an image on each of the above, a paper discharge means for discharging the paper on which the image is formed by the image forming means to the outside of the main body, a paper discharge tray for receiving the paper discharged by the paper discharge means, A switching gate is provided between the paper discharge means and the paper discharge tray, for switching between a first position for guiding the paper to the paper discharge tray and a second position for guiding the paper on the manual feed tray. , The paper having the image formed on the front surface is guided to the manual feed tray through the switching gate, the paper is taken into the main body from the manual feed tray, and the image is formed on the back surface by the image forming means to form a double-sided image. Do Automatic double-sided image forming apparatus characterized by was Unishi.