JPH05324074A - Device for correcting belt position of electrophotographic printer - Google Patents

Abstract

PURPOSE:To correct the belt position without requiring large amounts of current by moving the position of a tension roller by means of a planetary gear or cam. CONSTITUTION:When a belt 5 does not travel the prescribed position, a sensor 6 detects it to output the position information, thereby operating the electromagnetic clutch of a gear 13 provided with an electromagnetic clutch. Accordingly, the gear 13 is connected with a stud 12. The gear 13 is engaged with a planetary gear 14, which is driven by a driving gear 11 being driven by a driving roller 1 through a gear line 17. Thus, a return spring 10 rotates the planetary gear 14 on the gear 13, making it to be engaged with the gear 15 which is pushed out of mesh with the gear 16. By moving the planetary gear 14, a link lever 8 connecting the center of the planetary gear 14 to the end section is rotated, correcting the position of the belt 5 by operating a tension roller 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt position correcting device for an electrophotographic printer which simultaneously performs transfer and fixing using a belt.

[0002]

2. Description of the Related Art FIG. 7 is a mechanical system diagram showing an example of a belt position correcting device for a conventional electrophotographic printer, and FIG. 8 is a perspective view of the example shown in FIG.

As shown in FIGS. 7 and 8, a conventional belt position correcting device for an electrophotographic printer, which uses a belt to perform transfer and fixing at the same time, has a belt 65 and a belt 65.
And a tension roller 63 that is held at the tip of a link lever 68 that is rotatable about a fulcrum 69 and that applies tension to the belt 65. Is the drive roller 6
1 and tension roller 63 and guide roller 64
It is wound around and runs in the direction of arrow A.

A sensor 66 is provided on the running path of the belt 65, and when the belt 65 does not run at a predetermined position, the sensor 66 detects it and outputs position information. The belt 65 is moved to a predetermined position by operating the norenoid 67 and driving the other end of the link lever 68 to displace the tension roller 63.

When the norenoid 67 is sucked, the belt 65 moves in a direction away from the sensor 66. When the belt 65 moves to the limit of the allowable range, the norenoid 67 is returned. When the norenoid 67 returns, the belt 65 moves toward the sensor 66.

[0006]

The conventional belt position correcting device for the electrophotographic printer as described above has a drawback that a large current is required to operate the solenoid. Further, when continuously operated, there is a problem that the output decreases due to heat generation and the correction accuracy of the belt position deteriorates.

[0007]

A belt position correcting device for an electrophotographic printer according to the present invention comprises a belt, a drive roller for driving the belt, a tension roller for applying a tension to the belt, and the tension at one end. A link lever that holds a roller and holds a planetary gear at the other end and is capable of pivotal movement, a sensor that detects the traveling position of the belt and outputs position information, and a drive gear that is driven by a drive source of the drive roller. And a gear with an electromagnetic clutch for connecting and disconnecting the shaft of the link lever and the planetary gear, and changing the connection state of the planetary gear and the drive gear based on the position information. Is.

Further, the belt position correcting device for an electrophotographic printer of the present invention holds a belt, a driving roller for driving the belt, a tension roller for applying a tension to the belt, and one end for holding the tension roller. A link lever that holds a planetary gear at the other end and is capable of pivotal movement, a sensor that detects the traveling position of the belt and outputs position information, and connects and disconnects the shaft of the link lever and the planetary gear. Equipped with a gear with an electromagnetic clutch,
An independent drive source that drives the movement of the gear with the electromagnetic clutch and is rotatable in both forward and reverse directions is provided.

Further, the belt position correcting device for an electrophotographic printer of the present invention includes a belt, a driving roller for driving the belt, a tension roller which is rotatable and applies tension to the belt, and the belt. A sensor that detects a traveling position and outputs position information, a cam that displaces the tension roller based on the position information, a spring that faces the cam, and an independent drive source that rotates the cam. It is equipped with.

[0010]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a mechanical system diagram showing a first embodiment of the present invention, and FIG. 2 is a mechanical system diagram showing an operating state of the embodiment of FIG.

In the embodiment shown in FIG. 1, a belt 5, a driving roller 1 for driving the belt 5, and a link lever 8 which is rotatable about a stud 12 are held at the tip of the belt lever 5 with respect to the belt 5. The belt 5 is wound around the drive roller 1, the tension roller 3 and the guide roller 4, and travels in the direction of arrow B.

A sensor 6 is provided on the traveling path of the belt 5, and when the belt 5 does not travel at a predetermined position, the sensor 6 detects it and outputs position information.
The electromagnetic clutch of the gear 13 with the electromagnetic clutch is operated according to the position information from. As a result, the gear 13 with the electromagnetic clutch, which has been idling until now, is connected to the stud 12. The gear 13 with an electromagnetic clutch meshes with the planetary gear 14, and the planetary gear 14 is driven by the drive gear 11 driven by the drive roller 1 via the gear train 17 and rotates in the direction of arrow B via the gear 16. I am allowed to do it. Therefore, the planet gear 14 is driven by the force of the return spring 10.
It rolls on the gear 13 with an electromagnetic clutch, disengages from the gear 16 and comes into mesh with the gear 15. Due to the movement of the planetary gear 14, the wrinkle lever 8 connecting the central portion of the planetary gear 14 to the end portion is rotated, and the tension roller 3 is operated to correct the position of the belt 5.

At the same time when the planet gear 14 meshes with the gear 15, the electromagnetic clutch of the gear 13 with the electromagnetic clutch is cut off, so that the planet gear 14 runs idle. FIG. 2 shows the state at this time.

When the belt 5 does not run at a predetermined position in the state shown in FIG. 2, the electromagnetic clutch of the idling electromagnetic clutch gear 13 is energized, and the electromagnetic clutch gear 13 is connected to the stud 12. It As a result, the planetary gear 14 rolls on the gear 13 with an electromagnetic clutch due to its own weight, disengages from the gear 15 and engages with the gear 16.

At the same time that the planet gear 14 meshes with the gear 16, the electromagnetic clutch of the gear 13 with the electromagnetic clutch is cut off, so that the planet gear 14 runs idle. FIG. 1 shows the state at this time.

As described above, by rolling the planetary gear 14 on the gear 13 with the electromagnetic clutch, the link lever 8 connecting the central portion of the planetary gear 14 to the end portion is rotated, whereby the tension roller is rotated. 3 can be operated to correct the position of the belt 5.

FIG. 3 is a mechanical system diagram showing the second embodiment of the present invention, and FIG. 4 is a mechanical system diagram showing the operating state of the embodiment of FIG.

Belt 25 and drive roller 2 of this embodiment
1 and link lever 28 and tension roller 2
The basic configuration and operation of the gear 3, the guide roller 24, the sensor 26, the electromagnetic clutch gear 33, and the planetary gear 34 are the same as those in the embodiment of FIG.

The gear 33 with an electromagnetic clutch is driven by an independent motor (not shown). The state of FIG.
That is, when the sensor 26 detects that the belt 25 does not travel at a predetermined position while the planetary gear 34 is in contact with the stopper 38, the electromagnetic clutch of the gear 33 with an electromagnetic clutch operates based on the position information from the sensor 26. Then, the gear 33 with the electromagnetic clutch and the shaft 39 are coupled. As a result, the planetary gear 34 rolls on the gear 33 with an electromagnetic clutch and moves in the direction of arrow D, and the stopper 3
8 and leave the stopper 37 in contact. This planetary gear 34
By this movement, the link lever 28, which connects the central portion of the planetary gear 34 to the end portion, is rotated, and the tension roller 23 is operated to correct the position of the belt 25.

When the planetary gear 34 comes into contact with the stopper 37, the electromagnetic clutch gear 33 is de-energized, so that the planetary gear 34 idles. FIG. 4 shows the state at this time.

When the belt 25 does not run at a predetermined position in the state shown in FIG. 4, the electromagnetic clutch of the idling electromagnetic clutch gear 33 is energized, and the electromagnetic clutch gear 33 is connected to the shaft 39. As a result, the planetary gear 34 rolls on the electromagnetic clutch-equipped gear 33 and moves in the direction of arrow E by an independent reverse motor, and leaves the stopper 37 to come into contact with the stopper 38 to reach the state of FIG. Return. When the planetary gear 34 comes into contact with the stopper 38, the electromagnetic clutch of the gear 33 with an electromagnetic clutch is cut off, and the planetary gear 34 idles.

FIG. 5 is a mechanical system diagram showing a third embodiment of the present invention, and FIG. 6 is a mechanical system diagram showing an operating state of the embodiment of FIG.

Belt 45 and drive roller 4 of this embodiment
1 and tension roller 43 and guide roller 44
The basic structure and operation of the sensor 46 and the sensor 46 are the same as those in the embodiment of FIG.

The tension roller 43 has a spring 49.
The cam 50 is pressed in the direction of arrow F by the cam 50 and is opposed to the cam 50. The cam 50 is driven by an independent motor (not shown). In the state shown in FIG. 5, the cam 50 pushes the tension roller 43 to compress the spring 49. In this state, the sensor 46 indicates that the belt 45 does not travel at a predetermined position.
Is detected, the motor for driving the cam 50 operates according to the position information from the sensor 46, and the cam 50 is rotated by half. This causes the tension roller 43 to move to the cam 50.
The spring 49 extends to move the tension roller 43, and the position of the belt 45 is corrected. FIG. 6 shows the state at this time.

When the belt 45 does not run at a predetermined position in the state shown in FIG. 6, the cam 50 is rotated half a turn to the state shown in FIG. This makes the tension roller 4
3 is a state in which the spring 49 is compressed and the belt 45
Correct the position of.

[0027]

As described above, the belt position correcting device for the electrophotographic printer of the present invention is configured to move the position of the tension roller by the planetary gear or the cam without using the solenoid. This has the effect of not requiring a large current for belt position correction. In addition, even if it is operated continuously, stable operation can be performed, so that there is an effect that highly accurate position correction can be performed.

[Brief description of drawings]

FIG. 1 is a mechanical system diagram showing a first embodiment of the present invention.

FIG. 2 is a mechanical system diagram showing an operating state of the embodiment of FIG.

FIG. 3 is a mechanical system diagram showing a second embodiment of the present invention.

FIG. 4 is a mechanical system diagram showing an operating state of the embodiment of FIG.

FIG. 5 is a mechanical system diagram showing a third embodiment of the present invention.

6 is a mechanical system diagram showing an operating state of the embodiment of FIG.

FIG. 7 is a mechanical system diagram showing an example of a belt position correction device of a conventional electrophotographic printer.

FIG. 8 is a perspective view of the example of FIG. 7.

[Explanation of symbols]

 1, 21, 41, 61 Drive roller 3, 23, 43, 63 Tension roller 4, 24, 44, 64 Guide roller 5, 25, 45, 65 Belt 6, 26, 46, 66 Sensor 8, 28, 68 Link laver 10 Return Spring 11 Drive Gear 12 Stud 13/33 Gear with Electromagnetic Clutch 14/34 Planetary Gear 15 Gear 16 Gear 17 Gear Train 37/38 Stopper 39 Shaft 49 Spring 50 Cam 67 Norenoid 69 Support Point

Claims (3)

[Claims] 1. A belt, a driving roller for driving the belt, a tension roller for applying a tension to the belt, a link that holds the tension roller at one end and a planetary gear at the other end, and is a link that can rotate. A lever, a sensor that detects the traveling position of the belt and outputs position information, a drive gear driven by a drive source of the drive roller, and a coupling / separation of the shaft of the link lever and the planetary gear. And a gear with an electromagnetic clutch, wherein a coupling state between the planet gear and the drive gear is changed based on the position information, and a belt position correcting device for an electrophotographic printer. 2. A belt, a drive roller for driving the belt, a tension roller for applying a tension to the belt, a link for holding the tension roller at one end and a planetary gear for the other end, and the link being rotatable. A lever, a sensor for detecting the traveling position of the belt and outputting position information, and a gear with an electromagnetic clutch for connecting / disconnecting the shaft of the link lever and the planetary gear. A belt position correction device for an electrophotographic printer, which is provided with an independent drive source capable of rotating in both forward and reverse directions to drive the movement of the electrophotographic printer. 3. A belt, a drive roller that drives the belt, a tension roller that is rotatable and applies tension to the belt, and a sensor that detects a traveling position of the belt and outputs position information. A belt position of an electrophotographic printer comprising a cam for displacing the tension roller based on the position information, a spring provided to face the cam, and an independent drive source for rotating the cam. Correction device.