JP2685956B2 - Paper cassette control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a paper cassette feeding control device.

(Prior Art) Conventionally, an electrophotographic printer irradiates a charged photosensitive drum with a light source to form an electrostatic latent image on its surface, attaches toner to the electrostatic latent image, and develops the electrostatic latent image. The toner image is transferred to the recording medium.

Since the electrophotographic printer has a medium feeding mechanism, the recording medium contained in the paper cassette is taken out one by one by driving the hopping roller.

FIG. 2 is a diagram showing a medium feeding mechanism of a conventional printer.

In the figure, the medium feeding mechanism has a structure in which paper cassettes are installed above and below, and the upper paper cassette is called a first tray 1 and the lower paper cassette is called a second tray 2. Each tray 1 and 2 has its own paper feed mechanism.

In the tray body installed in the first tray 1, there is a setting lever 4A below the plate 3A on which the recording medium is placed, and the setting lever 4A
A coil spring 5A is arranged below the.

The paper feed mechanism of the first tray 1 has four gears, and the rotation is transmitted in the order of the motor gear 6A, the idle gear 7A, the idle gear 8A, and the planetary gear 9. The planet gear 9 has a shaft movable in the left-right direction, and selectively transmits a force to the registration gear 10 or the hopping gear 11A.

The hopping roller 12A is mounted coaxially with the hopping gear 11A, and rotates in the same direction as the hopping gear 11A rotates. Further, the registration roller 13 is mounted coaxially with the registration gear 10, and the registration gear 10
And rotate in the same direction. The pressure roller 14 is rotatably supported so as to face the registration roller 13.

 Next, the paper feed mechanism of the second tray 2 will be described.

The second tray 2 is installed at the bottom of FIG.
A plate 3B is attached to the second tray 2, and a recording medium is placed on the plate 3B. A setting lever 4B is provided below the plate 3B, and a coil spring 5B is provided below the setting lever 4B.

The paper feeding mechanism of the second tray 2 has three gears, namely a motor gear 6B, an idle gear 7B and a hopping gear.
Rotation is transmitted in the order of 11B. The hopping roller 12B is mounted coaxially with the hopping gear 11B.

Next, the operation of the medium feeding mechanism having the above configuration will be described.

When the first tray 1 is installed in the upper paper feed mechanism,
The setting lever 4A pushes up the plate 3A on which the medium is placed by the force of the compression coil spring to bring the medium into contact with the hopping roller 12A. Then, when the second tray 2 is installed in the lower paper feed mechanism, the setting lever 4B similarly pushes up the plate 3B on which the medium is placed by the force of the compression coil spring 5B, so that the medium is hopping roller.
Contact 12B.

First, of the trays 1 and 2, feeding is started from the first tray 1, and when the medium of the first tray 1 is used up, the feeding of the second tray 2 is started.

When feeding from the first tray 1, use the motor gear
When 6A rotates in the direction of the solid arrow and rotates the idle gear 8A in the direction of the solid arrow, the planet gear 9 moves the shaft to the right while rotating in the direction of the solid arrow, and hopping gear 11A.
And the hopping roller 12A is rotated in the direction of the solid line arrow via the hopping gear 11A. As a result, the medium on the first tray 1 that is in contact with the hopping roller 12A is sent out by the hopping roller 12A, passes through the paper feed sensor 15, and is hopped to the registration roller 13.

Then, after the recording medium passes through the paper feed sensor 15, when a pulse motor (not shown) that drives the motor gear 6A counts a certain number of pulses, the motor gear 6A reverses in the direction of the dotted arrow. As a result, idle gear 8A, planetary gear 9
Also rotates in the direction of the dotted line arrow to rotate the resist gear 10 in the direction of the dotted line arrow to feed the medium into the apparatus.

When it is determined by the paper feed sensor 15 that one recording medium has been fed, the motor gear 6A rotates again in the direction of the solid arrow to feed the recording medium from the first tray 1.

When the recording medium of the first tray 1 is used up, a sensor (not shown) detects that there is no recording medium, and the planet gear 9 remains engaged with the registration gear 10. Subsequently, when feeding the recording medium from the second tray 2, the motor gear 6B rotates in the direction of the solid line arrow to rotate the idle gear.
Rotate 7B in the direction of the solid arrow. The idle gear 7C rotates the hopping gear 11B and the hopping roller 12B in the direction of the solid line arrow to hop the recording medium on the second tray 2 with which the hopping roller 12B is in contact.

The recording medium hopping from the second tray 2 is
It is sent to the upper registration roller 13 through the sheet guide 16. At this time, there is no movement of the planet gears 9 from the first tray 1 unlike the case of hopping, and the registration roller 13
When the paper feed sensor 15 senses the medium from the second tray 2, it starts rotating in the direction of the dotted line arrow, and when it senses that the medium has passed, the rotation is stopped.

(Problems to be Solved by the Invention) However, in the paper feed control device from the paper cassette having the above-described configuration, after the medium passes the paper feed sensor 15, the pulse motor (not shown) that drives the motor gear 6A has a constant number of pulses. When counting, the motor gear 6A is controlled to reverse. Moreover, this pulse number is the same both when feeding from the first tray 1 and when feeding from the second tray 2.

However, comparing the case of feeding paper from the first tray 1 and the case of feeding paper from the second tray 2, when the paper is fed from the first tray 1, the registration roller
In order to rotate 13 the planetary gear 9 must be moved to mesh with the registration gear 10. For that purpose, it takes time to move the planetary gear 9, and the timing at which the planetary gear 9 is pulled into the registration roller 13 is deviated. As a result, the printing start position is different.

The present invention solves the problems of the above-described conventional paper cassette feeding control device, and the printing start position differs between when feeding from the first tray and when feeding from the second tray. An object of the present invention is to provide a paper feed control device from a non-paper cassette.

(Means for Solving the Problem) Therefore, in the paper cassette feeding control apparatus of the present invention, first and second trays (first tray, second tray) for accommodating recording media, and the first tray ,
It has first and second hopping rollers for hopping the recording medium accommodated in the second tray, and first and second hopping gears which rotate integrally with the first and second hopping rollers. There is.

The first and second hopping gears are driven by first and second motor gears rotated by a pulse motor.

On the downstream side of the first and second hopping rollers, a registration roller for feeding the hopping recording medium,
A registration gear that rotates integrally with the registration roller is provided.

A planet gear is movably disposed between the first hopping gear and the registration gear, and the first hopping gear and the registration gear are selectively meshed by switching the first motor gear between forward and reverse, 1 transmits the rotation of the motor gear.

A paper feed sensor for detecting a recording medium is provided in the vicinity of the registration roller, and when the paper feed sensor detects the recording medium during the paper feeding from the first tray, the first set time After that, the forward / reverse switching of the first motor gear is performed. When the sheet is fed from the second tray, the sheet feed sensor detects the recording medium, and thus the registration roller is rotated after the second set time.

The second set time is set longer than the first set time by a time required for the planetary gear to move between the first hopping gear and the registration gear by switching the first motor gear between forward and reverse.

(Operation) According to the present invention, the first and second trays (first tray, second tray) for accommodating the recording medium as described above and the hopping of the recording medium accommodated in the first and second trays First and second hopping rollers, and first and second hopping rollers that rotate integrally with the first and second hopping rollers.
A second hopping gear, the first and second hopping gears being a first motor rotated by a pulse motor;
Since it is driven by the second motor gear, the first and second motor gears are
The recording media can be individually taken out from the tray.

A registration roller that feeds the hopping recording medium and a registration gear that rotates integrally with the registration roller are provided on the downstream side of the first and second hopping rollers. A planetary gear is movably arranged between the register gear and the registration gear, and the first hopping gear and the registration gear are selectively meshed by switching the first motor gear between the forward and reverse directions to rotate the first motor gear. introduce. Therefore, the planet gear is the first
The recording medium accommodated in the second tray is hopped by the first hopping roller when meshed with the hopping gear, and the hopped recording medium is sent to the registration roller when meshed with the registration gear. To be paper.

A paper feed sensor for detecting a recording medium is provided in the vicinity of the registration roller, and when the paper feed sensor detects the recording medium during the paper feeding from the first tray, the first set time Later, when the first motor gear is switched between forward and reverse, the planet gear moves between the first hopping gear and the registration gear, and the resist roller is rotated. When the sheet is fed from the second tray, the sheet feed sensor detects the recording medium, and thus the registration roller is rotated after the second set time. The second set time is set longer than the first set time by the time required for the planetary gear to move between the first hopping gear and the registration gear by switching the first motor gear between forward and reverse.

Therefore, when the paper is fed from the first tray and the paper is fed from the second tray, the registration rollers are rotated after the same time has elapsed since the paper feed sensor detected the recording medium.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a flowchart of the paper feeding operation by the paper feeding control device from the paper cassette of the present invention.

Since the medium feeding mechanism has the same structure as the conventional one, its description is omitted.

The operation of the medium feeding mechanism will be described with reference to FIG.

When the first tray 1 is installed in the upper paper feed mechanism,
The setting lever 4A pushes up the plate 3A on which the medium is placed by the force of the compression coil spring 5A to bring the medium into contact with the hopping roller 12A. Then, when the second tray 2 is installed in the lower paper feeding mechanism, the setting lever 4B pushes up the plate 3B on which the medium is placed by the force of the compression coil spring 5B, and the medium is hopping roller 12B.
Contact.

Of the trays 1 and 2, the first tray 1 starts to feed paper, and when the medium in the first tray 1 is used up, the second tray 2 starts to feed paper.

When the step motor gear 6A rotates in the direction of the solid line arrow to rotate the idle gear 8A in the direction of the solid line arrow, the planetary gear 9 moves in the right direction while rotating in the direction of the solid line arrow to mesh with the hopping gear 11A. The hopping roller 12A is rotated in the direction of the solid line arrow via the hopping gear 11A. As a result, the medium on the first tray 1 that is in contact with the hopping roller 12A is sent out by the hopping roller 12A, passes through the paper feed sensor 15, and is hopped to the registration roller 13.

Steps-Next, after the recording medium passes through the paper feed sensor 15, a counter (not shown) starts counting, and when a constant count value k is counted, the motor gear 6A reverses in the direction of the dotted arrow. This allows idle gear 8A,
The planet gear 9 also reverses in the direction of the dotted arrow to rotate the registration gear 10 in the direction of the dotted arrow.

Then, when the paper feed sensor 15 for feeding the medium into the apparatus detects that one medium has been fed, the motor gear 6A again rotates in the direction of the solid arrow to feed the medium from the first tray 1.

When the medium in the first tray 1 is used up, a sensor (not shown) detects that there is no medium, and the planetary gear 9 remains engaged with the registration gear 10. When feeding the medium from the second tray 2, the motor gear 6B rotates in the direction of the solid line arrow to rotate the idle gear 7B in the direction of the solid line arrow. The idle gear 7B rotates the hopping gear 11B and the hopping roller 12B in the direction of the solid line arrow to hop the medium on the second tray 2 with which the hopping roller 12B is in contact. The medium hopping from the second tray 2 is sent to the upper registration roller 13 through the sheet guide 16.

Steps-After the recording medium hopped from the second tray has passed the paper feed sensor 15 so that the print start position is the same as that of the first tray 1, the count value set in the counter is increased. That is,
The registration gear 10 and the registration roller are increased by increasing the amount of movement of the planetary gear 9 as compared with the case of feeding from the first tray 1.
13 rotations are delayed. In this case, the first tray 1
It is not necessary to move the planetary gear 9 as in the case of feeding paper from.

In this way, by individually controlling both trays 1 and 2, it is possible to make the print start position the same.

It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible based on the gist of the present invention.
They are not excluded from the scope of the present invention.

For example, the invention can be applied not only to a printer but also to a copying machine having two or more paper cassettes.

As described above in detail, according to the present invention, the paper feed sensor for detecting the recording medium is provided in the vicinity of the registration roller, and when the paper is fed from the first tray, the paper feed sensor is provided. When the paper sensor detects the recording medium and the first motor gear is switched between forward and reverse after a first set time, the planetary gear moves between the first hopping gear and the registration gear, and the registration roller moves. Is rotated. On the other hand, when the sheet is fed from the second tray, the sheet feed sensor detects the recording medium, so that the registration roller is rotated after the second set time, and the second set time is the first set. Since the time required for the planetary gear to move between the first hopping gear and the registration gear is made longer than the first set time by switching the motor gear between forward and reverse,
When the paper is fed from the first tray and the paper is fed from the second tray, the registration rollers are rotated after the same time has elapsed since the paper feed sensor detected the recording medium.

Therefore, the print start position can be the same when the paper is fed from the first tray and when the paper is fed from the second tray.

[Brief description of the drawings]

FIG. 1 is a flow chart of a paper feeding operation by a paper cassette feeding control device of the present invention, and FIG. 2 is a view showing a medium feeding mechanism of a conventional printer. 1 ... First tray, 2 ... Second tray, 3A, 3B ...
Plate, 4A, 4B ... Setting lever, 5A, 5B ... Coil spring, 6A, 6B ... Motor gear, 7A, 7B, 8A ... Idle gear,
9 ... Planetary gear, 10 ... Registration gear, 11A, 11B ... Hopping gear, 12A, 12B ... Hopping roller, 13 ... Registration roller, 14 ... Pressure roller, 15 ... Paper feed sensor.

Claims (1)

(57) [Claims] 1. (a) First and second trays for accommodating recording media, and (b) First and second hopping rollers for hopping the recording media accommodated in the first and second trays. (C) first and second hopping gears that rotate integrally with the first and second hopping rollers, and (d) first and second hopping gears that drive the first and second hopping gears.
A second motor gear, (e) a registration roller that feeds the hopping recording medium, (f) a registration gear that rotates integrally with the registration roller, and (g) a space between the first hopping gear and the registration gear. A planetary gear that selectively meshes by switching the first motor gear between forward and reverse, and transmits the rotation of the first motor gear to selectively perform hopping and paper feeding; (h) near the registration roller A paper feed sensor for detecting the recording medium, and (i) when the paper is fed from the first tray, the paper feed sensor detects the recording medium so that the first motor gear Means for switching between forward and reverse, and (j) when the sheet is fed from the second tray, the sheet feeding sensor detects a recording medium so that the registration roller is set after a second set time. (K) the second set time is only the time required for the planetary gear to move between the first hopping gear and the registration gear by switching the first motor gear between forward and reverse. A paper cassette control device from a paper cassette, characterized in that it is longer than the first set time.