JPS60137733A - Device for sending sheet out - Google Patents

Abstract

PURPOSE:To suck and send out a sheet without winding it, by applying a voltage across only a part of an electrode pattern provided along the total circumference of an endless belt, to generate an electrostatic field between electrodes located at a portion which needs a sucking force. CONSTITUTION:A control circuit 9 acts to close a switch SW to apply the voltage of a DC power source 10, between a pair of fixed contact members 7a, 7b. The contact members 7a, 7b come into contact with same of groups of moving contact members 4a, 4b exposed on the inside of an electrostatic suction belt 2, so that the contact members 7a, 7b are connected to groups of isolated electrodes 5a, 5b corresponding to an outside portion of a basic material 3. As a result, the voltage is applied to some of the group of electrodes 5a, 5b to generate a strong electric field between the electrodes 5a, 5b so that paper P is sucked on a dielectric member 6 and sent out in a direction B. At that time, the application of electricity at an insulation roller 1a is stopped so that the sucking force of the belt 2 drops. For that reason, the paper P is sent out in the direction B without being wound on the roller 1a.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a sheet feeding device (1) used for feeding out sheets of paper, film, etc. in copying machines, printing machines, etc.
1 related.

[Prior art]

Conventionally, copying machines, printing machines, etc. (2) have been used as feeding devices to feed out sheets one by one from stacked stacks of sheets, such as paper or film, by pressing a rubber roller against the sheet stack and rotating it to generate friction force. Devices that send out sheets of paper or the like are widely used.As sheet feeding devices, there are also known sheet feeding devices that suck air through a thin tube and send out sheets of paper or the like.

However, in the former case, the frictional force of the rubber roller decreases due to deterioration due to environmental factors such as time, heat, ions, toner, etc., and when the frictional force decreases, inconveniences occur such as feeding is no longer performed. There is a problem with the lifespan of the rubber.

On the other hand, in the latter case (2), there are problems such as the equipment is complicated (2), the equipment becomes larger and the cost increases (2), there are problems such as increased noise.

[Purpose of the invention]

This invention was made in view of the above points, and uses electrostatic adsorption force to feed the sheet, and also uses a device such as a special separating claw to peel the sheet I from the feeding mechanism. The purpose of this is to prevent the sheet from wrapping around itself even if it is not in use.

[Structure of the invention]

In order to achieve the object stated in -I-, this invention uses an endless belt formed around the entire circumference of an electrode pattern for generating electrostatic adsorption force as a feeding mechanism, and furthermore, the electrode pattern of the entire circumference (two-feeding Rather than doing
A part of the electrode pattern (only two voltages are applied to form an electrostatic electric field between the electrodes located in the part where adsorption force is required,
This allows the sheet to be sucked and sent out.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Figures 1 to 4 show an embodiment of the present invention.
A case is shown in which power is supplied to an endless belt for feeding consisting of an insulating phase and an electrode pattern from the non-adsorption surface side.

In Fig. 1, (1a) and (1b) are rotated by bearings (a pair of absolute H
'r'l roller, (2) is an insulating roller (la), (
lb) Interval i: A stretched endless electrostatic adsorption belt, and a part of this electrostatic adsorption belt (2) is loaded with paper P as a sheet to be sent out in the direction of arrow B by a mechanism (not shown). Pressure N is applied from below and they are pressed together. As shown in FIG. 2, the endless electrostatic adsorption belt (2) has a base material (3) made of a flexible insulating layer such as polyester or polyimide, and each line in the width direction of the base material is formed on the inner surface of the base material (3). 'l1llIC=, as shown in FIG. (4, b)... group is provided. Also, on the opposite surface of the base material (3),
is an isolated electrode (5
a), (,5a)..., (5b), (5b)・
... are provided alternately along the moving direction (==) of the electrostatic adsorption belt (2), and the moving side contact piece (4a) is connected to the isolated electrode (5a), and the moving side contact piece (4, b) is an isolated electrode (5b), and each corresponding moving side contact piece is in contact with the isolated electrode.
Isolated electrodes (5a), (5a)..., (5+
1).

(5b)...A dielectric material (6) is attached to the surface of the side where the group is provided.

The dielectric (6) includes isolated electrodes (5a), (5aL..., (
5b), (5+))... As described later, when applying a voltage between these electrodes to form an electrostatic field between these electrodes to attract the paper P, in order to strengthen the attraction force, the dielectric constant is It has a high volume resistivity of about 1010 Ωcm and is made of a flexible additive, for example, a polymer matrix mixed with barium titanate and carbon.

The isolated electrodes (5a), (5a)-, (5b), (
5t+)--Group and moving side contact pieces (4a), (4a
)-, (xen), (+b)-... groups are provided over the entire circumference of the endless electrostatic adsorption belt (2), and the isolated electrodes (5a), (5a)=., (5b).

(5b)... Isolated electrodes (5a) located in a part between the groups, that is, in the part of the electrostatic adsorption bell I' (2) that is in pressure contact with the paper P and requires adhesion force, (5a) - , (5b
), (5b)・=Group part (In order to supply power only to the second part, on the inner circumferential side of the part of the endless electrostatic adsorption bell I・+21 that is in pressure contact with the paper P, Moving side contact pieces (4・a), (4a)..., (4b), (4
b)...a pair of fixed contact pieces (7a) in contact with the group;
(7b) is installed, and electric wires (8) and (8) are drawn out from each, and in Figure 4 (1 not shown),
A voltage of, for example, 3000 V is applied between the fixed contact pieces (7a) and (7b) from the DC power supply (10) via the switch SW closed by the control circuit (9).

(7b) and each of the above-mentioned moving side contact pieces (4a), (4
a)...

Through (4b), (4b)..., voltage is applied only to the portion of the isolated electrode (5) where voltage needs to be applied while the endless electrostatic adsorption belt (2) is moving; The part (- indicates that no voltage is applied.

Next, the operation of feeding out the sheets P one by one from the stacked stack of sheets in the above configuration (2) will be described.

First, when a printing or copying operation is started, the control circuit (9) is activated and the switch SW is closed, and the voltage of the DC power supply (10) is applied to the pair of fixed contact pieces (7a).

(7b) added in between. This pair of fixed contact pieces (7a
).

(7b) is a moving side contact piece (4a) exposed inside the endless electrostatic adsorption belt (2), (4a) --(4
b), (4b)... are in contact with a part of the group, respectively, and the moving side contact pieces (4a), (4a) =..., (4b
), (4b) One group is the corresponding isolated electrode (5a) provided outside the profiteer (3) as described above.

Since the isolated electrodes (5a), (5b), (5b)... are connected to each other, the voltage from the DC power supply (10) is applied to the isolated electrodes (5a), (5a)...

(5b), (5b)... will be applied to part of the group.

When the voltage is applied in this way, the isolated electrode (5a
), (5b) (1 strong electric field is generated, and the paper P is attracted to the dielectric (6) via the dielectric (6). When the paper P is attracted, a motor (not shown) etc. The insulating rollers (la), (11)) rotate in the input direction (two revolutions), and accordingly, feeding of the attracted paper P in the B direction is started.

When feeding out the paper P, on the insulating roller (lb) side, the electrostatic adsorption belt (2) moves (accompanied by the movement of the electrostatic adsorption belt (2), one after another (1) new isolated electrodes (5a), (5b)
At the same time as the application of 1 is applied, the insulating roller (1a)
On the side, the application of the voltage is cut off, and in this way the endless electrostatic adsorption belt (2) moves (2).

Therefore, the parts where adsorption force is required (isolated electrodes in two places (5a
).

(5b) Electricity is supplied only between the insulating roller (la), which does not feed the paper P, and the electrostatic adsorption belt (2) located on the outer periphery of (1, b) and the paper P are in pressure contact with each other. The side that is being held is on the opposite side (the electrostatic adsorption belt (2
) isolated electrodes (5a), (5a)-, (
5+)), (5b) ・"No voltage is applied between the groups. Therefore, the fixed contact pieces (7a), (7b)
Although a strong adhesion force is generated on the surface of the dielectric (6) where the movable contact pieces (4a) and (4b) come into contact with each other, the electrostatic adsorption belt on the insulating roller (1a) side (2) When the paper P is gradually separated from the paper P (secondly, when the power is not supplied as described above), the suction force rapidly decreases,
The paper P is reliably sent out in the direction of arrow 13 along the outer periphery of the insulating roller (1a) without being wrapped around it.

this. In order to feed the paper P using the principle of electrostatic adsorption, and to supply power to the endless electrostatic adsorption belt (2) with an electrode pattern formed around the entire circumference, The part where force is required (two isolated electrodes (5a)
) , (5a)..., (5b), (5b) ・=
For this reason, there are problems with the life of the rubber, as in the case of conventional rubber roller feeding methods (two-way rollers), and device problems, such as in the case of vacuum suction feeding methods. In addition to being able to obtain a small and inexpensive feeding device without problems such as increase in size, cost increase, or noise,
A device such as a separation claw for peeling off the paper P sent out from the electrostatic adsorption belt (2) is also unnecessary, and it is possible to make it reliable (only two feeds can be performed). In other words, it is possible to make use of electrostatic adsorption force. In the case where the paper P is sent out by adsorption, if the entire circumference of the endless electrostatic adsorption belt (2) (two wafers) [its isolated electrodes (5a),
=, (5b), (5b) If power is constantly supplied to the group, suction will continue even after feeding, and the paper P will wind up, causing separation. Although a device such as a claw is required, with the above structure, the paper P can be reliably sent out without being wrapped around the paper P without using such a special device for peeling.

Figures 5 to 7 show other embodiments of the present invention. This is done from the front side.

That is, in FIG. 5, a pair of rollers (lla)
.

The endless electrostatic adsorption bell) +12+ is stretched between C1 and b), as in the embodiment described in nIJ, but in this example, the above electrostatic adsorption bell) (12+ is shown in Fig. 6). and the outside of the base material (4) (two-arc vertical electrode (13a)) as shown in FIG.

Only one group (], 3a) -, (13b), (13b) is provided, and a pair of fixed contact pieces (14a), (],
4b) is formed into a ski shape, and these are electrostatic adsorption bells)
(On the outer peripheral side of 12+, that is, on the paper suction surface side (two are provided).

Isolated electrodes (13a), (13
a)...

(13b), (13b)"' group consists of isolated electrodes (1,
8a), (13a)- can come into contact with one ski-shaped fixed contact piece (14=a) (2, and the isolated electrodes (13b), (13b)... Each ski has its end exposed from the dielectric (15) so as to be able to contact the fixed contact piece (14b), and serves as a fixed electrode that directly contacts these exposed parts. fixed contact pieces (14a), (Mb
) is fixed to the paper suction surface side by an appropriate method, and is supplied with power from a DC power supply at a voltage of, for example, aooo'v (2) in the same manner as in the previous embodiment. Isolated electrodes (13a) , (13a) ・, Q
sb), Qab) - The dielectric (15) attached to the center of the surface on the side where the group is provided may have the same structure as in the previous embodiment.

In the above configuration, when the paper P receives pressure N from below and comes into contact with the electrostatic adsorption bell) +12+, the fixed contact piece (i
ia), (14b) are isolated electrodes (13a), (13
a) -, (tab), (13b)... Isolated electrode (18a) in the part that contacts the sheet surface of the group and requires suction force
, (], 8b), power is supplied, suction force is generated, and the paper P is suctioned. And Laura (], l
When a) and (Ilb) are rotated in the A direction by the driving source, the adsorbed paper P is moved by the fixed contact pieces (14・a) and (1
4b) and is sent out in the direction of arrow B.

Therefore, in the case of this embodiment, as in the embodiment described above, electrostatic adsorption force is used to feed the paper, and power is supplied only to the parts where adsorption force is required, making it compact and compact. Of course, it is possible to obtain a feeding device that is inexpensive and highly reliable, and does not require a dedicated separation claw or other device. (=fixed contact piece (14a) as described above constituting means for applying voltage,
(14b) will also serve as a separating material, so
Even if the paper P does not separate,
It also has the advantage of not causing paper jams.

In addition, in each example, electrostatic adsorption belt (2), (1
As for the voltage of the DC power supply applied to a part of the electrode pattern formed in 2), a sufficient feeding force can be obtained with 5ooov, but it is necessary to detect the thickness and area of the paper P and feed it back to the applied voltage. For example, from very thin paper to thick paper,
For example, it can be used as a paper feeding device when using paper having different thicknesses from about 40 microns to about 500 microns.

〔Effect of the invention〕

As described above, this invention eliminates problems such as the lifespan of rubber that occurs when feeding with conventional rubber rollers, and problems such as increasing the size of the device and noise when feeding by vacuum suction, and allows the feeding device to be made smaller and smaller. In addition to being inexpensive and highly reliable, it also requires a device such as a special separation claw to peel the sheet from the endless belt for feeding, which is formed with an electrode pattern that generates electrostatic adsorption force. It also has the advantage of being able to prevent the sheet from wrapping around itself.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a side view of one embodiment f11 of the present invention, Fig. 2 is a sectional view showing a contact portion, Fig. 3 is an electrode arrangement diagram for explaining the arrangement of electrodes, and Fig. 4 is a side view of one embodiment f11 of the present invention. The figure shows a circuit diagram for supplying 71g, FIG. 5 is a side view showing another embodiment of the invention, FIG. 6 is a top view of the same, and FIGS. FIG. 3 is a partial cross-sectional view showing the relationship between fixed contact pieces. Code explanation (21+12+... Electrostatic adsorption belt (4a) (
4b)...Moving side contact piece (5a) (5b) (1
3a) (13b) --Isolated electrode (7a) (7b) (1
4a) (14b) ＋＋＋＋＋・Fixed contact piece Patent applicant: Fuji Xerox Co., Ltd. Agent: Tomohiro Tsuchinaka, patent attorney: Katsuo Naruse, Figure 1, Figure 4, Figure 4, Figure 1-9

Claims (1)

[Claims] The electrode pattern for generating electrostatic adsorption force is arranged around the entire circumference (
An endless belt for sheet feeding formed in two parts,
1. An endless belt (means for applying a voltage only to a part of the electrode pattern to attract two sheets) by forming an electrostatic electric field.