JPH10329959A - Paper feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeder in which positioning of stacked paper sheets can be carried out stably even when stopping precision specific to a driving means is dispersed. SOLUTION: The subject paper feeder is provided with a stacking base 2 to which stacked paper sheets 1 are placed, a driving means 3 elevating/lowering the stacking base 2, an uppermost paper position detecting means 6 detecting arrival of the uppermost paper sheet 1a at the predetermined position when the stacking base 2 is elevated, and a controlling means 10 controlling the driving means 3 according to the uppermost paper position detecting means 6. A delay time, which can be regulated, is provided in the duration from the detection of the uppermost paper sheet 1a by means of the uppermost paper position detecting means 10 to the stop of the driving means 3. In this way, dispersion in the stopping precision specific to the driving means 3 is adsorbed, so that the stacked paper sheets 1 can be positioned stably in spite of the dispersion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding device such as a copying machine and a printer.

[0002]

2. Description of the Related Art In recent paper feeders such as copiers and printers, the paper feed tray has been provided with front loading, so that the paper feed tray and the paper feed separation unit are separated, and a guide plate between them is also provided. Be divided. As a result, the distance from the leading end of the laminated paper on the paper feed tray to the entrance of the paper feed separation unit becomes longer, and therefore, when the laminated paper is transported, highly accurate positioning of the laminated paper is required.

[0003]

In such a conventional paper feeder, the positioning accuracy for feeding the laminated paper to the paper feed separation section depends on the motor-specific stop accuracy of the driving means of the laminating table, the lamination paper. This is aggravated by load fluctuations due to fluctuations in the stacking amount and fluctuations in the paper entry direction due to variations in the paper entry direction, and variations in the paper entry direction due to the curl amount of the laminated paper, leading to paper damage and jams during transport. Improvement was required, and there were restrictions on the amount of paper loaded and the amount of paper curl.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a sheet feeder capable of stably positioning a laminated sheet even if the stop accuracy inherent to the driving means varies.

[0005]

According to a first aspect of the present invention, there is provided a laminating table on which a laminating paper is placed, driving means for moving the laminating table up and down, and a top sheet of the laminating paper when the laminating table is raised. In a paper feeding device including a top sheet position detecting unit that detects that a predetermined position has been reached, and a control unit that controls a driving unit based on detection information of the top sheet detected by the top sheet position detecting unit, the control unit includes: A delay time is provided from when the uppermost sheet position detecting means detects the uppermost sheet to when the driving means is stopped,
The delay time can be adjusted.

According to the first aspect of the present invention, a delay time is provided from when the uppermost sheet position detecting means detects the uppermost sheet to when the driving means is stopped, and the delay time is adjustable. Even if there is inherent stop variation of the driving means, the positioning of the laminated paper can be performed with high accuracy, and stable positioning performance and feeding performance of the laminated paper can be obtained.

According to a second aspect of the present invention, in accordance with the first aspect of the present invention, there is provided a stacked paper load amount detecting means for detecting a stacked paper load amount, and the control means is provided for the stacked paper load amount detecting means. The delay time can be varied based on the load amount detection information.

According to the second aspect of the present invention, there is provided a stacked paper loading amount detecting means for detecting a stacked amount of the stacked paper loaded on the loading table, and the stacked paper loading amount detecting means is provided. By varying the delay time based on the amount detection information, it is possible to perform stable positioning of the laminated paper even if the load amount varies, and to obtain stable transport performance. In addition, since the position where the uppermost sheet reaches the paper feed separation unit can be kept substantially constant in response to the change in the load amount (rotation angle) of the rotary type loading table, the restriction on the load amount can be eased. it can. Further, even if the length of the loading table is reduced and the rotation angle is increased, the loading table can be downsized because it can cope with it, and the load on the driving means can be reduced. I can do it.

According to a third aspect of the present invention, in the first aspect of the present invention, a laminated paper curl amount detecting means for detecting a curl amount of the laminated paper is provided, and the control means includes a laminated paper curl amount detecting means. It is characterized in that the delay time can be changed based on the delay time.

According to the third aspect of the present invention, the delay time is varied based on the curl amount detection information of the curl amount detection means, so that the paper sheet separation can be performed stably even if the curl amount of the paper varies. The sheet can be conveyed to the paper stack, and the restriction on the curl amount of the sheet can be reduced.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a paper feeding device of the present invention. The paper feeding device shown in FIG. 1 is a device used for a copying machine, a printer, or the like, and includes a stacking table 2 on which a stacked paper 1 is placed. . The elevating end 2 b of the stacking table 2 is rotatable about a fulcrum 2 a and is supported by one end of a lift arm 4. The other end of the lift arm 4 is fixed to an output shaft 3a of the motor 3 as a driving means.

As a result, when the motor 3 rotates the lift arm 4 in the R direction, the lifting end 2
b can be lifted in the T direction with the laminated paper 1 placed thereon. The driving of the motor 3 is performed by a command from the control means 10.

A pickup roller 7 is disposed near the lifting end 2b of the stacking table 2 and above the stacking end 2b.
The pickup roller 7 is rotated in the U direction by the driving force of the motor 7a, so that the uppermost sheet 1
a is fed along the V direction. Further, a pair of paper separating rollers 8, 8 is disposed in front of the raising / lowering end 2b of the stacking table 2, and one of the paper separating rollers 8 is rotated in the W direction by the driving force of the motor 8a. The uppermost paper 1a of the laminated paper 1 can be fed in the V direction by frictional force and further conveyed to a registration roller (not shown) near, for example, a photoconductor.

A filler 5 is disposed in the vicinity of the paper feed roller 7, and the filler 5 is provided with a light blocking portion 5a and a paper placing portion 5a.
b. The filler 5 can be rotated in the E direction by the pin 5c. When the paper placing portion 5b is lifted in the E direction by the uppermost sheet 1a of the laminated paper 1 on the elevating end 2b of the stacking base 2, the light blocking portion 5a Enter between the transmission type sensors 6.

The transmission type sensor 6 is a top sheet position detecting means for detecting that the top sheet 1a of the laminated sheet 1 on the lifting end 2b has reached a predetermined position, and includes a light emitting unit such as a light emitting diode. And a light receiving unit such as a photodiode for receiving light from the light emitting unit. The light blocking unit 5a blocks light by entering between the light emitting unit and the light receiving unit. This allows
The transmission type sensor 6 provides the control unit 10 with the top sheet position detection information.

The feature of the embodiment of the present invention is that the predetermined position is determined by taking into account the delay in the control of the motor 3, that is, the variation in the inherent stopping accuracy of the motor 3, and the conveyance of the uppermost sheet 1a. In this case, the delay time is set to a position shorter than the optimal position for performing the delay time.

This delay time can be given to the control means 10 by setting it in the operation section 12 in advance.
By doing so, the variation in the stop accuracy (stop time) inherent to the motor 3 is suppressed, and the top sheet 1a can be reliably transported to the sheet separation rollers 8, 8 of the sheet separation section 9 by the pickup roller 7.

In FIG. 1, the lifting end 2 of the
When the stacking amount (number of sheets) of the laminated paper 1 on b decreases and fluctuates,
The load applied to the output shaft 3a of the motor 3 via the lift roller 4 also varies. When the stacking amount of the stacking base 2 is large, the load applied to the output shaft 3a of the motor 3 is large, and the rotation overrun of the output shaft 3a of the motor 3 is relatively small. However, when the stacked amount of the laminated paper 1 on the stacking table 2 is small, the load applied to the output shaft 3a of the motor 3 is small, and the overrun of the rotation of the output shaft 3a of the motor 3 becomes relatively large. The uppermost sheet 1a goes above a predetermined position.

A loading table 2 which rotates as shown in FIG.
In the case of (1), when the load is large, the rotation angle θ shown in FIG. 2 is small, so that the uppermost sheet 1a is surely conveyed to the sheet separation rollers 8, 8 of the sheet separation section 9, but the load is small. When the number is small, the rotation angle θ shown in FIG. 2 becomes large, and even at the same position of the uppermost sheet 1a, the uppermost sheet 1a is sent above the sheet separating section 9 as shown in FIG.

Accordingly, in the embodiment of the present invention, as shown in FIG. 1, a stacking paper stacking amount detecting means 14 for detecting the stacking amount of the stacking paper 1 stacked on the stacking table 2 is provided. When the stacking amount is small based on the stacking amount detection information of the stacking paper generated by the stacking amount detection unit 14 of the stacking paper,
The control means 10 determines the delay time from when the transmission type sensor 6 as the uppermost sheet position detecting means detects the uppermost sheet 1a to when the motor 3 as the driving means stops, when the stacked amount of the laminated paper 1 is large. The control unit 10 controls the height so that the height at which the uppermost sheet 1a reaches the sheet separation rollers 8, 8 of the sheet separation unit 9 is kept substantially constant. Note that, for example, a sensor that detects the weight of the laminated paper can be used as the laminated paper loading amount detection unit 14.

Further, in FIG. 1, if the laminated paper 1 on the loading table 2 is curled, the height at which the uppermost paper 1a reaches the paper feed separation rollers 8, 8 of the paper feed separation section 9 naturally changes. Come. As shown in FIG. 3, when the laminated paper 1 is face-curled, it is shifted upward from the target position, and when the laminated paper 1 is back-curled, it is lower than the target position. Will be shifted. The amount of deviation from the target position varies depending on the degree of each curl.

Accordingly, in the embodiment of the present invention, as shown in FIG. 1, the curl amount detecting means 16 is provided, and the degree of curl detected by the curl amount detecting means 16 is given to the control means 10. I have. This curl amount detecting means 1
For example, a sensor 6 having a light emitting unit and a light receiving unit and optically detecting the height of the curl can be employed.

Based on the curl amount detection information generated by the curl amount detecting means 16, the control means 10 takes a short delay time from the detection of the uppermost sheet 1a to the stop of the motor 3 in the case of face curl, and in the case of a back curl, The delay time from the detection of the uppermost sheet 1a to the stop of the motor 3 is increased. The control means 10 changes the degree of fluctuation of the delay time according to the degree of the curl amount, and keeps the height at which the uppermost sheet 1a arrives at the sheet separation rollers 8, 8 of the sheet separation part 9 substantially constant. To control.

FIG. 4 shows another embodiment of the present invention. The loading table 32 shown by a solid line is shorter than the loading table 2 shown by a broken line. The lift arm 4 is fixed to the output shaft 3a, and the loading table 32 rotates in the R direction about the fulcrum 32a by driving the motor 3, as in the embodiment of FIG.

When the short loading table 32 is used, if the uppermost sheet 1a of the laminated paper 1 is lifted by the same amount as the loading table 2 indicated by the broken line, the rotation angle θ1 shown in FIG. The rotation angle θ is larger than the rotation angle θ, but even in such a case, the loading table 32 shown in FIG.
Is provided for detecting the stacking amount of the stacked paper 1 loaded on the stacking paper 1, and the delay time is determined based on the stacked sheet stacking amount detection information generated by the stacked paper stacking amount detection means 14. , The stable positioning of the laminated paper 1 can be performed even if the load amount fluctuates, and stable transport performance can be obtained.

Further, even in the case of the rotary type loading table 32, the position where the uppermost sheet 1a reaches the paper feed separation section 9 can be kept substantially constant in accordance with the change in the loading amount (rotation angle). Thereby, the loading table 32 can be made smaller than the loading table 2 and the load on the motor 3 can be reduced, so that the motor and the like can be reduced in size and cost can be reduced.

The present invention is not limited to the above embodiment.
The lift arm 4 connected to the output shaft 3a of the motor 3
Not only the arm type member but also a rotary cam type member can be adopted. The filler 5 may be of another type that rotates about the pin 5c.

[0028]

According to the first aspect of the present invention, a delay time is provided from when the uppermost sheet position detecting means detects the uppermost sheet to when the driving means is stopped, and the delay time can be adjusted. Therefore, even if there is inherent stop variation of the driving means, the positioning of the laminated paper can be performed with high accuracy, and stable positioning performance and feeding performance of the laminated paper can be obtained.

According to the second aspect of the present invention, there is provided a stacked paper loading amount detecting means for detecting the stacked amount of the stacked paper stacked on the loading table, and the stacked paper loading amount generated by the stacked paper loading amount detecting means is provided. By varying the delay time based on the detection information, it is possible to perform stable positioning of the laminated paper even when the load amount varies, and to obtain stable transport performance. Also,
In response to the change in the load (rotation angle) of the rotation type loading table,
Since the position where the uppermost sheet reaches the sheet separation section can be kept substantially constant, the restriction on the stacking amount can be eased. Further, even if the length of the loading table is reduced and the rotation angle is increased, the loading table can be downsized because it can cope with it, and the load on the driving means can be reduced. I can do it.

According to the third aspect of the present invention, the delay time is varied based on the curl amount detection information of the curl amount detecting means, so that the sheet feeding / separating unit for the paper is stable even if the curl amount of the paper fluctuates. , And the restriction on the curl amount of the paper can be eased.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of a sheet feeding device of the present invention.

FIG. 2 is a diagram illustrating a state in which a loading arm is raised by a lift arm in the sheet feeding device of FIG. 1;

FIG. 3 is a diagram illustrating a state in which a sheet of laminated paper on a loading table is curled in the sheet feeding device of FIG. 1;

FIG. 4 is a diagram showing an example using a small-sized lamination base.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Laminated paper 2 Lamination board 3 Motor (drive means) 6 Transmission type sensor (uppermost paper position detecting means) 10 Control means 14 Laminated paper loading amount detecting means 16 Laminated paper curl amount detecting means

Claims (3)

[Claims] 1. A laminating table on which a laminating paper is placed, a driving means for raising and lowering the laminating table, and an uppermost paper position for detecting that the uppermost sheet of the laminating paper has come to a predetermined position when the laminating table rises. A sheet feeding device comprising: a detecting unit; and a control unit that controls the driving unit based on the uppermost sheet detection information of the uppermost sheet position detecting unit. A sheet feeder, wherein a delay time is provided before the driving means is stopped, and the delay time is adjustable. 2. A method according to claim 1, further comprising the step of detecting a stacking amount of the stacking paper, wherein the control unit changes the delay time based on the stacking amount detection information of the stacking amount detection unit. The paper feeding device according to claim 1, wherein 3. A laminated paper curl amount detecting means for detecting the curl amount of the laminated paper, wherein the control means makes the delay time variable based on the laminated paper curl amount detecting means. 2. The paper feeding device according to 1.