JPS62244829A - Method for controlling feeding device - Google Patents

Abstract

PURPOSE:To prevent a toner image from shrinking or a picture image from being disturbed by controlling so that a conveyance preventing force may not act on a sheet material by a frictional rotary body at the time of conveying said sheet material by means of a regist roller, in a picture image forming device such as a copying machine, etc. CONSTITUTION:As a motor 16 starts to rotate, at the same time, a sensitive drum 12 also starts to rotate and, after a certain time has passed, a paper feeding clutch 17 is connected to transmit rotation to a frictional rotary body 2 and start the feeding of a sheet. After a certain time, the clutch 17 is disconnected by means of a controller C, while in the meantime, a loop is formed between regist rollers 13, 14 and the frictional rotary body 2. Then, the regist clutch 19 is connected by means of a signal which is generated in order to synchronize a toner image developed on the drum 12 with the sheet and by means of the signal of a clock pulse means 18 which is rotated synchronized with the drum 12, to feed the sheet toward the drum 12. And, after a certain time, the clutch 17 is disconnected, and the frictional rotary body 2 is stopped again. The off-timing is carried out by signals from switches 41-43.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Savings] The present invention relates to a method for controlling a feeding device, and more particularly, to a method for controlling a feeding device, for example, a feeding device for feeding a sheet material in an image forming device such as a copying machine or an N1 recorder. The present invention relates to a method of controlling a sending device.

As for the above-mentioned feeding devices, there is a sheet material feeding device in which double feeding of sheet materials is prevented by pressing n[4 blocking members with a friction rotating body (roller) K, so this will be taken as an example. The details are described below, but are not limited to this.

[Conventional technology]

Conventionally, as shown in FIG. 1, for example, a sheet-like material feeding device consists of a friction rotor 2 rotatably driven by a shaft 1 and a member having a high coefficient of friction such as rubber or synthetic resin. It has a rubbing pad 3, and the 85 pad 3 is fixed to the other end of the separation member 5 which is pivotally supported by a support shaft 5a, and a spring tensioned on the other end of the nuclear separation member 5. 6Vc F) It is pressed against the friction rotating body 2 at a predetermined pressure.

Further, a paper feed cassette 7 is disposed facing the friction rotary body 2 and is removable from the paper feed section, and the paper feed cassette 7 is urged with its free end toward the rotary body 2 by a spring 10. The storage box 9 includes a mounting table 8 and a box-shaped storage box 9 that supports the rotating end 8a and stores the sheet material.

The uppermost sheet-like material 11 such as a large number of papers stacked on the mounting table 8 is in contact with the friction rotating body 2. It is fed by frictional force based on rotation in the direction. Furthermore,
When two or more sheet-like materials 11 are fed, the lower sheet-like material is separated by pressure contact with the friction pad 3, and its feeding is regulated and separated, thereby preventing double feeding in which two or more sheet-like materials 11 are fed. There is.

Furthermore, the storage boxes 9 differ depending on the size of the sheets to be stored and placed, and as shown in FIG. When installed in the paper device, a plurality of switches 'to'2+'5 are provided as detection means on the copying machine main body side.
In particular, when any one of them is turned on, a signal for detecting the size of the sheet stored in the cassette 7 is obtained.

In this way, the sheets separated one by one are transferred to a pair of register rollers 15 and 14 provided for aligning the powder image on the photosensitive drum 12 with the sheet, which is rotated by the friction rotor 2. transported by. A sensor 15 is disposed upstream of the pair of register rollers [, 14], and in addition to detecting the arrival and residence time of the sheet to determine paper jam, the sensor 15 also detects the leading edge of the sheet. A timer means that calculates the distance to the pair of register rollers generates a signal to control the stop timing of the friction rotary body 2 in order to form an appropriate loop between the sensor and the register rollers. It is well known that the above-mentioned loop is formed as a means for correcting the skew feeding of the sheet, and furthermore, the sheet is rotated by an image leading edge cycle emitted from the photosensitive drum 12 or an optical device (not shown) for exposing the image. The register rollers 13 and 14 are started to rotate from the signal 1c, and the sheet is conveyed again and sent onto the photosensitive drum 12, where the toner image is transferred onto the surface thereof.

At this time, in the conventional example of the device, the friction rotor 2 is not rotationally driven, and a one-way clutch (not shown) is disposed between the shaft 1 and the friction rotor 2, so that the seat 11
When the sheet a is conveyed by the register rollers 13 and 14, the iM rubbing rotor 2 is unlocked from the shaft 1 and is freely rotated by the conveying force of the sheet. Since this rotation is a driven rotation, when the rear end of the sheet passes through the contact point between the jP friction rotor 2 and the separation pad 3, the rotation of the friction rotor 20 stops and no rotational driving force is applied by the shaft 1. As long as the next sheet 11b is not sent out.

[Problem that the invention seeks to solve]

However, the separation pad 3 does not rotate and remains in pressure contact with the friction rotating body 2, and since its surface is made of a material having a high coefficient of friction, a high stopping force is generated against the sheet. Therefore, the register roller 15,
This method has drawbacks such as slippage in the 14th section, variation in synchronization with the toner image, that is, variation in registration storage, and furthermore, the toner image on the sheet shrinks in the paper feeding direction.

For this phenomenon, registration roller 15. Increase the pressure contact force of Jl and increase the sheet conveying force to Jl! It may be possible to make it superior to the stopping force of the rubbing pad 3, but in this case, the 9 load f#l at the start of rotation of the registration rollers 13 and 14 becomes large, and when an electrostatic latent image is formed.

There is a risk that an impact is applied to the drive of the drum 12 during development, resulting in image disturbance, that is, blurring.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned drawbacks of the conventional example, and has a feeding i position that prevents the frictional co-rotating body from acting on the sheet material when the sheet material is transported by the registration means or the transport roller. The purpose is to explain all methods of fR1+ control.

In order to achieve the above object, the control method according to the present invention includes:
A friction rotor that feeds the sheet material by rotating in contact with the surface of the laminated sheet material, a resist means that temporarily stops the fed sheet material to form a loop, and then conveys the sheet material again, and a sheet. and detection means for detecting the dimensions of the sheet material, the rotation of the limb friction rotating body is stopped after a predetermined loop is formed in the sheet material by the registration means, and thereafter, when the sheet material is started to be conveyed by the registration means. Then, the rotation of the bale friction rotor was started, and the bales and wrinkled friction rotor were rotated and fed until they reached the vicinity of the rear end beyond the length of the sheet material in the conveyance direction detected by the detection means. It is characterized by stopping rotational feeding due to

Further, a friction rotating body that feeds the sheet material by making rotational contact with the surface of the stacked sheet materials, a conveyance means that takes over and conveys the fed sheet material, and a detection means that detects the dimensions of the sheet material, While the sheet material is being conveyed by the core conveying means, the y-friction rotating body is rotated to feed the sheet material, and the length of the sheet material in the conveying direction detected by the detecting means is detected near the rear end. It is characterized in that the rotational feeding by the friction rotary body is stopped after the rotational feeding is carried out until the end.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be explained in detail using figures. FIG. 1 is used as a sectional view of an embodiment of the present invention, and FIG. 3 is a schematic diagram of its drive system. Next, FIG. 4 shows a block diagram of the drive circuit. Meanwhile, in the third factor, the same members as those in FIG.

The control method will be explained based on FIGS. 1 and 3. Simultaneously with the start of rotation of the motor 16, the photosensitive drum 12 starts rotating via the gear 3) 1.3), and after a predetermined period of time, the feed clutch 17 is turned on and drive is transmitted to the friction rotary body 2 to feed the sheet. Start paying. In other words, the rotation of the gear 3) rotates the friction rotating body 2 via the gear 33, the belt 34, the clutch 17, the pulley 35, and the belt 56. As described above, the sheets are separated one by one by the friction batt 5, and when the leading edge is detected by the sensor 15, the clutch 17 is turned off after a predetermined time by a timer means (included in the controller C). During this time, a loop is formed between the friction rotating bodies of the registration rollers. Next, the resist clutch 19 is turned on by a signal issued by the clock pulse means 18 which rotates in synchronization with the drum 12 in order to synchronize the toner image burnt on the drum 12 with the sheet. Drive is transmitted to the rollers 13 and further to the cooperating registration rollers 14, so that the sheet is sent out toward the drum 12.

That is, the rotation of gear 3) is transmitted to roller 15 via gear 35, belt 34, pulley 38, gear 39, gear 40, and clutch 19.

Immediately after the registration clutch 19 is turned on, the paper feed clutch 1
7 is turned on again and starts assisting sheet feeding. The difference in the on time of the feed clutch 17 with respect to the registration clutch 19 is determined by taking into consideration the response speed of both clutches.The paper feed clutch 17 is turned on earlier than the registration clutch 19, resulting in a huge loop and bending of the sheet. This is to avoid the risk of causing problems. Conversely, the paper feed clutch 17
The on-timing of the switch was delayed and the loop was terminated. !
! It suffices if the timing is to turn on before the rubbing rotor becomes a load.

Next, after a predetermined period of time, the paper feed clutch 17 is turned off, and the friction rotary body 2 stops again. The on-timing is determined by calculating the length from the pressure contact part of the IP rubbing quadrotor 2 with the friction butt 3 to the rear end of the sheet that has not yet been fed, based on the signals from the switches 41 to 45 that detect the size of the sheet. sheet f
, the P end may be taken immediately after passing the contact portion between the friction rotating body 2 and the friction butt 3. For example, the loop length is subtracted from the detected sheet material dimension, and this remaining amount dimension and the rotational speed of the rotating body 2 are referred to. At this time, it is necessary to turn off the paper feed clutch 17 at a timing that takes into account response errors of both clutches.

As described above, since the friction rotor 2 performs auxiliary feeding until immediately after the rear end of the sheet is finished being fed, no load is placed on the conveyance of the registration rollers 13 and 14. Also,
Registration roller j3. j4 stops after a predetermined time has elapsed after the rear end of the sheet material passes the sensor 15.

FIG. 5 is a block chart showing the operation of the present invention.

In addition, even if the machine does not have a sheet size detection means, set a small size sheet that can be easily transported in the machine, and for other sizes, check the sheet size in some way during the copying operation. By inputting it, you can increase the effect of Giant 1.

Further, in this embodiment, a friction butt that is pressed against the friction prevention member is used, but even if this friction rotation rotates in the opposite direction to the friction rotation body, the same problem will occur, and the present invention is also effective against this problem. be.

Further, the present invention is also applicable to a cassette type device using a separating claw 50 as shown in FIG.

Further, as the registration means, a registration claw may be provided on the upstream side of the registration roller, and the tip of the sheet material may be brought into contact with this registration claw. 2. Furthermore, as a further embodiment, as shown in FIG.
, 54, the friction rotary body 52 continues to rotate and feed. In this case, the rotational feeding of the friction rotor 52 may be stopped a predetermined time after the tip of the note is detected by the sensor 55. Other aspects are the same as those of the previous embodiments.As described above, according to the embodiments of the present invention, the simple mechanism of rotating the sheet feed roller later can reduce the variation in the registration storage η and the shrinkage of the image. This method has the advantage that it does not cause shake, etc., and that the registration rollers or conveyance rollers can be rotated with a light load.

〔Effect of the invention〕

Since the method of controlling the feeding device according to the present invention is as described above, there is an advantage that when the sheet material is transported by the registration means or the transport means, the transport inhibiting force due to the friction 1'El does not act on the sheet material.

[Brief explanation of drawings]

1- is a schematic configuration diagram of a conventional feeding device, FIG. 2 is an enlarged view showing a cassette size detection section, and FIG. 3 is a main part of a feeding device for carrying out the control method according to the present invention. A perspective view of
FIG. 4 is a block circuit diagram for carrying out the control method according to the present invention, FIG. 5 is a flowchart, and FIGS. 6, 1 and 7 are schematic diagrams of the respective embodiments. . 2.52...Friction rotating body 3...Friction butts 4-45...Switch 7 Departing paper cassette 8...Place table 9...Storage box 11...Sheet material 11a...Sheet material (Top paper) 116... Sheet material (next group) 12... Photosensitive drum 13.14... Registration roller 1555... Sensor 16... Motor 17... Paper feed clutch 18, 1 clock pulse Means 19...Resist clutch

Claims (4)

[Claims] (1) A friction rotor that feeds the sheet material by making rotational contact with the surface of the stacked sheet materials, and a resist means that temporarily stops the fed sheet material to form a loop, and then conveys the sheet material again. and a detection means for detecting the dimensions of the sheet material, stopping the rotation of the friction rotary body after forming a predetermined loop in the sheet material by the registration means, and then transporting the sheet material by the registration means. At the same time, the rotation of the friction rotary body is started, and after rotating and feeding the sheet material until it reaches the vicinity of the rear end beyond the length of the sheet material in the conveyance direction detected by the detection means, A method of controlling a feeding device, the method comprising: stopping rotational feeding by the friction rotor. (2) A friction rotating body that feeds the sheet material by making rotational contact with the surface of the stacked sheet materials, a conveyance means that takes over and conveys the fed sheet material, and a detection means that detects the dimensions of the sheet material. , and the friction rotating body is rotated and fed while the sheet material is being conveyed by the conveyance means, and after the length of the sheet material in the conveyance direction detected by the detection means has been exceeded. 1. A method of controlling a feeding device, comprising: stopping rotational feeding by the friction rotary body after rotationally feeding the material until it reaches the vicinity of an end. (3) A friction rotor that feeds the sheet material by making rotational contact with the surface of the stacked sheet materials, and a resist means that temporarily stops the fed sheet material to form a loop, and then conveys the sheet material again. and, after forming a predetermined loop in the sheet material by the registration means, the rotation of the friction rotary body is stopped, and then, as the sheet material starts to be conveyed by the registration means, the rotation of the friction rotor body is stopped. After starting the rotation and performing rotational feeding until reaching the vicinity of the rear end beyond the length of the sheet material in the conveying direction detected by the detection means, the rotational feeding by the friction rotating body is stopped. A method of controlling a feeding device, characterized in that: (4) A friction rotating body that feeds the sheet material by rotating in contact with the surface of the laminated sheet material, and a conveying means that takes over and conveys the fed sheet material, and the conveying means While conveying the sheet material, the friction rotary body is rotated to feed the sheet material, and the rotational feeding is continued until the sheet material reaches the vicinity of the rear end beyond the length of the sheet material in the conveyance direction detected by the detection means. 1. A method of controlling a feeding device, comprising: stopping rotational feeding by the friction rotary body after the friction rotary body has reached the position of the friction rotor.