JPH0192145A - paper feeder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a paper feeding device, such as a copying machine or a terminal printer, which has a paper feeding roller that feeds paper by sandwiching the paper between two rollers.

[Conventional technology]

Conventionally, as shown in Fig. 6, in a paper feed roller set, one or more rubber rollers are attached in the middle of one metal shaft, and the driving force from the main body is intermittently applied to one end of the metal shaft. a driving roller 1 equipped with a driving device 4 for transmitting information to the driving roller 1; a driven roller 2 made of metal or plastic that faces the driving roller 1; and a presser spring 3 that presses the driven roller 2 against the driving roller 1; Next, it consists of a release mechanism for releasing the pressing force. The driving roller 1 and the driven roller 2 are supported by the main body frame via bearings at right angles to the paper advancing direction 11. As the drive device 4, an electromagnetic clutch or a spring clutch is generally used, and it temporarily blocks paper coming in from an external paper feed device (not shown) and synchronizes with the printing mechanism of the main body (not shown). , feed the paper to the printing mechanism.

The release mechanism is as follows. Release lever 5
One end is rotatably connected to the plunger 6, the other end is connected to both ends of the driven roller 2, and is rotatably supported by a shaft 7 on a main body frame (not shown). When it is necessary to release the holding force on the paper, such as to feed the paper to the contact area between the drive roller 1 and the driven roller 2, or to remove paper caught between the drive roller 1 and the driven roller 2,
Energize solenoid 8. Then, the release lever 5 rotates around the shaft 7, lifts the driven roller 2, and releases the holding force on the paper.

The paper passes through the gate rollers described above in the following manner.

Paper is fed into the main body from an external paper feed unit (not shown). Paper is fed into the main body along the traveling direction 11 by a paper feeding device outside the main body (not shown) or manually. A vapor entry sensor 9 detects that paper has entered the main body. When the paper is further fed, the paper is guided along the paper guide 10 to the contact area between the drive roller 1 and the driven roller 2. During this time, the drive roller 2 is stopped. The paper feeding device described above feeds the paper slightly longer than the distance from the paper feeding device to the contact point between the driving roller 1 and the driven roller 2, and the leading edge of the paper is fed to the driving roller 1.
and press it against the contact part of the driven roller 2. Next, at a certain timing with a printing mechanism (not shown), the electromagnetic clutch or the spring clutch 4 is energized to move the drive roller 1 and start feeding the paper.

When the paper reaches another set of feed rollers (not shown) arranged at right angles to the paper traveling direction 11, the solenoid 8 is energized. Then, the release lever 5 rotates around the shaft 7, the driven roller 2 is lifted, and the holding force on the paper is released. Then, when paper accumulates due to the slight difference in feeding speed between the roller set and the gate roller set during surface feeding, the tray 9/ is released.

Further, when a paper jam occurs and the paper is to be removed, the above-mentioned release operation is performed.

[Problem that the invention seeks to solve]

The conventional example described above has the following drawbacks. (1
), unreliable. ■It is large scale. The reasons for this are as follows. - For example, in the case of a copying machine with an A4 size printing speed of about 10 pPm, the drive device 4 requires a torque of about 1.5 kgtcm in order to obtain sufficient paper feeding force. In order to turn on and off such a large load torque, a spring clutch with a diameter of about 40 mm and a length of about 30 mm, or an "ffi!! clutch" is used. High durability is required to withstand the instantaneous large load when the device 4 is turned on and off, and a large margin against speed fluctuations.Also, since the device 4 is turned on and off, the spring clutch and electromagnetic clutch are required to be worn out. In addition, as mentioned above, in order to obtain a paper feeding force of 1.5 kg, the contact force between the drive roller 1 and the driven roller 2 is required to be approximately 3 kg. and,
The driven roller 2 is warped, and there is a large difference in paper feeding force between the center and both ends of the shaft, causing the paper to meander. or,
The drive shaft 1 is fixed to the frame through a bearing, and since the above-mentioned force of 3 kg is supported by this bearing, wear resistance of the bearing and high rigidity of the frame are required. In addition, the release mechanism is equipped with solenoid 8 in order to release the contact force of 3 kg mentioned above.
A large output and large rigidity are required for the release lever 5 and shaft 7.

It is an object of the present invention to eliminate the above-mentioned drawbacks and realize a highly reliable and compact printing device.

[Means for solving problems]

The present invention uses a magnetic material to control one of a pair of paper feed rollers facing each other in a printing device in which it is necessary to control the paper feed intermittently or to temporarily release the holding force on the paper. This is a paper feeding device in which one side is constructed of one type, and the other side is constituted by an electromagnet.

〔Example〕

Examples will be described below using figures.

In FIG. 1, the driving roller 101 is made of a magnetic material, and the driven roller 1 is
This is an example in which 02 is constructed with an electromagnet.

The drive roller 101 is supported by a main body frame (not shown) via a bearing 104, and has a gear 103 fixed to one end thereof and receives driving force from the main body. The driven roller is supported by a guide 6 with freedom of rotation and vertical movement, and receives power from a drive circuit 107 via S poles 105 at both ends. The drive circuit 109 is connected to the signal line 108
Electric power is intermittently supplied to the driven roller 102 by signals sent from the main body via the main body. The paper is delivered to the paper feed roller set of the present invention shown in FIG. 1 by an external paper feeder (not shown) or a pair of paper feed rollers in the previous stage. When the electromagnet off signal is coming to the signal line 108, no force is acting between the drive roller 101 and the driven roller 102 to sandwich the paper, and the paper is held between the drive roller 101 and the driven roller 102.
Stops at contact point 2. A signal to turn on the electromagnetic roller is sent to the signal line 108 at a certain timing with a main body printing mechanism (not shown) or another main body mechanism. Then, a force is generated between the driving roller 101 and the driven roller 102 to clamp the paper, and paper feeding is started. When the paper reaches the paper feed mechanism such as the paper feed roller of the next stage, the signal line 108 is turned off again.
f signal is sent, and the driving roller 101 and the driven roller 102
There is no longer any force holding the paper between them, and the paper is freed, and the paper is no longer undulating or undulating, which is caused by the slight difference between the paper feed speed of the paper feed mechanism in the next stage and the paper feed speed of the paper feed roller set in Figure 1. It can prevent slipping. Further, if a paper jam occurs during paper feeding, a signal to turn off the electromagnet is sent from the main body to the signal line 108.

Then, the clamping force on the paper disappears, and the paper can be easily removed. The advantage of this embodiment is (1) high reliability. (2) It is small. The reason for this is that the large paper feeding force is transmitted by electrical on-off rather than frictional force transmission as in an electromagnetic clutch or a spring clutch, so there is less wear on the sliding parts. In addition, since the clamping force on the paper acts directly between the feed rollers,
Only about 173 of the force of the conventional example is applied to the bearing supporting the roller, the frame roller shaft. As a result, the life of the bearing section is greatly extended, and the rigidity of the shaft and main body frame can be reduced. The reason for (2) is that in the conventional example shown in FIG.
Because of the arrangement of the renoids 8, the conventional paper feeding device was a paper feeding device that was considerably wider than the paper passing area, but in this embodiment, the only thing that can be arranged outside the side of the paper passing area is the gear. , the sheet passing area plus approximately 10 mm.

FIG. 2 shows a driving roller 101 and a driven roller 102 divided into a plurality of parts.

In FIG. 3, the driving roller 101 and the driven roller 102 are divided into a plurality of parts, and each driven roller 102 has an electrode.
It is designed to be able to move up and down independently. Even when feeding envelopes or double-page paper with adhesive (with different thickness depending on the location), the multiple driven rollers 102 move up and down independently (therefore, there is no difference in the feeding force depending on the location). .

FIGS. 4 and 5 are diagrams showing examples of the arrangement of magnetic poles. Fourth
The figure shows an S pole and an N pole arranged in the longitudinal direction of the driven roller 101.

FIG. 5 shows magnetic poles arranged in the radial direction of the driven roller 202. The drive roller 201 and the driven roller 202 are cylindrical objects made of non-magnetic material.The drive roller 201 is rotatably supported by a main body frame (not shown) via a bearing 214, and the driven roller 202 is rotated and rotated in the vertical direction. It has a degree of freedom and is supported. A core 210 made of a magnetic material is inside the driving roller 201, an electromagnet 212 is inside the driven roller 202, and one of the magnetic poles is always connected to the driving roller 201.
It is fixed so as to face the contact point of the driven roller 202 and the driven roller 202. The drive circuit 107 and the electromagnet 212 are directly connected via a shaft 213 fixed to the electromagnet 212. This embodiment has a simple magnetic circuit design, with only one contact! As the magnetic roller of the drive roller described in the 0 or more embodiments, which has high reliability because it has no poles, it is possible to use a roller made of magnetic metal.

In addition, there are examples in which the magnetic roller is made of magnetic rubber, examples in which the magnetic roller is formed by covering the magnetic metal with a tube made of rubber or foamed resin, and examples in which the magnetic roller is formed by coating the magnetic metal with rubber. , the coefficient of friction of the drive roller increases, the reliability of paper feeding increases, the clamping force against the paper to obtain the same paper feeding force is small, the current flowing through the electromagnet of the driven roller also needs to be small, and the drive circuit 1
07. The reliability of the contact 105 can be improved.

In the above embodiments, the driving roller is made of a magnetic material and the driven roller is made of an electromagnet, but the driven roller can be made of a magnetic material and the driving roller can be made of an electromagnet in the same manner. or,
The magnetic rollers of the embodiments described above can be constructed from permanent magnets. As a result, the clamping force on the paper becomes even stronger, and if you want to release the clamping force on the paper, if you apply a current in the opposite direction to the electromagnet, the driving roller and the driven roller will repel each other, and there will be a gap between the driving roller and the driven roller. There is more space between them, which makes it easier to remove paper.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to realize a paper feeding device that is small and has highly reliable paper feeding performance.

[Brief explanation of the drawing]

FIG. 1 is a diagram of an embodiment. Figure ts2 is a diagram of an embodiment in which a driving roller and a driven roller are divided into a plurality of parts. FIG. 3 is a diagram of an embodiment in which the drive roller is divided into a plurality of parts, and the driven roller, electrode, guide, drive circuit, and signal line are provided independently for a plurality of days. FIG. 4 is a diagram of an embodiment in which magnetic poles are arranged in the longitudinal direction of the roller. FIG. 5 is a diagram of an embodiment in which magnetic poles are arranged in the radial direction of the roller. FIG. 6 is a diagram of a conventional example. 101... Drive roller 102... Followed roller 105... G1 pole 106... Guide 107... [Moving circuit 108... Signal line 210... Core 212... Electromagnet 1... Drive roller 2...Followed roller 4...Electromagnetic clutch or spring clutch 5...Release lever 6...Plunger 8...Solenoid and above Applicant Seiko Epson Corporation Figure 2

Claims (1)

[Claims] A paper feeding device comprising a paper feeding roller pair consisting of a magnetic roller made of a magnetic material and an electromagnetic roller made of an electromagnet and facing the magnetic roller.