JPS644173B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for supplying toner to a dry development device, such as a magnetic brush development device.

Conventionally, as a toner supply device for supplying toner to a dry type developing device, one having one toner tank and supplying the toner in the toner tank to the dry type developing device using a toner supplying means such as a supply roller has been known. ing.

However, with this toner supply device, the amount of toner supplied is not constant because the amount of toner in the toner tank is not constant, and blocking occurs easily in the toner tank. The drawback is that the toner tank has to be replenished from the outside many times because of the small amount of toner.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner supply device that supplies a constant amount of toner, is less likely to cause blocking, and reduces the number of times a toner tank is replenished from the outside.

The present invention includes a first toner tank containing toner for supplying toner to a dry developing device, and a second toner tank communicating with the first toner tank. A toner stirring member for stirring the toner is provided in the second
A toner transfer means is provided in the toner tank of the first toner tank.
A toner transfer amount regulating means is provided at the connecting portion between the toner tank and the second toner tank, and when the amount of toner in the first toner tank is less than a certain value, the toner transfer means is operated to control the amount of toner transferred to the second toner tank. It is characterized in that the toner in the toner tank is transferred to the first toner tank.

The present invention will be explained in detail based on the embodiments illustrated below.

In FIG. 1, reference numeral 1 designates a first toner tank, in which toner 2 is stored and an outlet 1a is formed at the bottom thereof. A supply roller 3 is arranged at the outlet 1a at the bottom of the first toner tank 1. A plurality of axial grooves are formed. At the end of the supply roller 3 protruding from the toner tank 1, two gears 4 and 5 are rotatably supported in series, and an electromagnetic clutch 6 is provided adjacent to the gear 4. The gear 4 is rotated by a drive means (not shown). A current is applied to the electromagnetic clutch 6 from the control circuit only when the toner concentration in the developer tank 7 of the magnetic brush developing device shown in FIG. 2 is lower than a certain value. The gears 4 and 5 are connected to the supply roller 3 so that the rotational force of the gears 4 and 5 is applied to the supply roller 3. When the supply roller 3 rotates, the toner contained in the groove falls into the developer tank 7.

A toner inlet 1b is formed above the side wall of the first toner tank 1, and a second toner tank 8 stores toner in the toner inlet 1b.
The lower part of is connected. First toner tank 1
A rotary rod 9 is disposed in the second toner tank 8, and the rotary rod 9 is rotatably supported by the side wall of the first toner tank 1. A rotating rod 9 protruding from the first toner tank 1 is fixed to a rotating shaft 10 rotatably supported at a predetermined position. A toner transfer amount regulating member 11 is provided at the connecting portion of the rotating rod 10 between the first toner tank 1 and the second toner tank 8, and as the rotating rod 9 rotates, the toner transfer amount regulating member 11 11 also rotates. A toner transfer member 12 is fixed to the toner transfer amount regulating member 11 and the rotary rod 9 located within the second toner tank 8 .

A rotary cylinder 13 is supported on the side wall of the first toner tank 1 on the side far from the second toner tank 8 so as to surround the rotary rod 9 and rotate separately therefrom. A toner stirring member 14 for stirring the toner 2 is disposed in the first toner tank 1, and an end portion of the toner stirring member 14 is fixed to the rotary cylinder 13, and as the rotary cylinder 13 rotates, a toner stirring member 14 is arranged. The toner stirring member 14 rotates. A disc-shaped detection plate 15 is fixed to the protruding end of the rotary cylinder 13. A gear 16 is rotatably supported on the rotating shaft 10 so as to mesh with the gear 5, and a rotary plate 17 is positioned at a position facing the detection plate 15 so as to rotate integrally with the gear 16. Fixed. A long hole is formed in the detection plate 15, and a pressing piece 17a is protruded from the rotary plate 17 so as to be located in the long hole. In addition to the long holes, a detection hole is formed in the detection plate 15, and a sensor 1 for detecting the detection hole is formed.
8 is arranged near the detection plate 15. The output of this sensor 18 is given to a control circuit 19.
An electromagnetic clutch 20 is provided adjacent to the gear 16, and a signal is applied to the electromagnetic clutch 20 from the control circuit 19. The electromagnetic clutch 20 connects the gear 16 to the rotating shaft 10 when a current is applied, so that the rotational force of the gear 16 is transferred to the rotating shaft 10.
be given to

A toner replenishment port 8a is formed in the upper part of the second toner tank 8.
A toner cartridge 21 for replenishing the second toner tank 8 with toner is rotatably attached to the end of the toner a.

The gears 4 and 5 are constantly rotated during copying, and the gear 16 meshing with gear 5 is also constantly rotated during copying. When the rotating plate 17 rotates integrally with the gear 16, the pressing piece 17a rotates and presses the edge of the elongated hole of the detecting plate 15, rotating the detecting plate 15 and rotating the rotating cylinder 13 integrated with the detecting plate 15. Also, a toner stirring member 1 integrated with this rotary cylinder 13
4 rotates. This toner stirring member 14 is a second
When rotated in the direction of arrow a in the figure, it falls freely from approximately the position shown in the figure. In order to allow the toner agitating member 14 to fall freely in this way, a long hole into which the pressing piece 17a is inserted is formed in the detection plate 15. Freely falling toner stirring member 14
In conjunction with this, the rotary cylinder 13 also rotates, and the detection plate 15 integrated therewith also rotates. The toner stirring member 14 falls freely and stops due to the resistance of the toner. The magnitude of the rotation angle due to free fall of the toner stirring member 14 is approximately inversely proportional to the amount of toner stored in the first toner tank 1. Therefore, the rotation of the detection plate 15 due to the free fall of the toner stirring member 14 is determined from the reference rotation angle of the detection plate 15 due to the free fall of the toner stirring member 14 corresponding to the reference value of the amount of toner stored in the first toner tank 1. The sensor 18 detects whether the angle is large or small and detects the amount of toner stored in the first toner tank 1. The sensor 18 includes a light emitting element and a light receiving element that are arranged to face each other with the detection plate 15 at the center. Even if the detection plate 15 rotates due to free fall, the detection plate 1
When the detection hole 5 does not pass between the sensors 18 and the amount of toner stored in the first toner tank 1 is less than the reference value, the detection plate 15 rotates due to the free fall of the toner stirring member 14. The detection hole of the detection plate 15 is configured to pass between the sensors 18 when the detection plate 15 is detected. The sensor 18 provides an output to the control circuit 19 only when the detection hole of the detection plate 15 passes between the sensors 18 . The sensor 18 performs a detection operation only for a predetermined time from the start of free fall of the toner stirring member 14.

The toner stirring member 14 stops on top of the toner after falling freely. Next, since the rotary plate 17 is always rotating, the pressing piece 17a again engages with the edge of the elongated hole of the detection plate 15 and presses it, thereby rotating the rotary cylinder 13 and the toner stirring member 14. In this way, the toner stirring member 14 rotates while repeating a state in which it intermittently falls freely and stops for a certain period of time. Note that the means for detecting the rotation angle of the detection plate 15 due to the free fall of the toner stirring member 14 may be one in which a magnet is attached to a portion of the detection plate 15 and the movement of this magnet is detected by a Hall element.

When the sensor 18 provides an output to the control circuit 19, the control circuit 19 applies current to the electromagnetic clutch 20 for a predetermined period of time to shift the gear 16 to the rotating shaft.
0 to rotate the rotary shaft 10, rotate the rotary rod 9 integral therewith, and rotate the toner transfer member 12 and toner transfer amount regulating member 11 integral therewith. When the toner transfer member 12 rotates, the toner in the second toner tank 8 passes through the toner transfer amount regulating member 11 and is transferred to the first toner tank 1.
gradually transferred inside. The toner transfer amount regulating member 11 has a large number of holes 1 in a disk as shown in FIG.
1a. Note that the toner transfer amount regulating member 11 may be fixed to the connecting portion between the first toner tank 1 and the second toner tank 8 without being rotated together with the rotating rod 9. Further, the toner transfer member 12 may be coil-shaped as shown in FIG. 4. Furthermore, the means for rotating the toner agitating member 14 while repeating a state in which the toner agitation member 14 is intermittently free-falled and stopped for a certain period of time is not limited to the above-mentioned one, and the gear 1
6 may be transmitted to the toner stirring member 14 by a one-way clutch.

An example of supplying the toner in the first toner tank 1 to the magnetic brush developing device is shown in FIG. 2, and will be described next.

A developer tank 7 is arranged below and surrounding the outlet 1a of the first toner tank 1, and a developer 22 made of magnetic powder and toner is stored in the developer tank 7. ing. The pumping roller 2 is placed so that the lower part is located in this developer 22.
3 is placed. This pumping roller 23 consists of a plurality of magnets 23b fixed to an immovable shaft 23a and a sleeve 23c surrounding these magnets and rotating in the direction of arrow b. A developing roller 25 is disposed above the lifting roller 23 and near the drum-shaped photoreceptor 24 on which an electrostatic latent image is formed. It consists of a magnet 25b and a sleeve 25c that surrounds them and rotates in the direction of arrow c.

The developer 22 is attached to the magnet 23b of the pumping roller 23.
The sleeve 23c moves in the rotating direction due to the magnetic force of the sleeve 23c and the rotational force of the sleeve 23c, and then the developing roller 2
The magnetic force of the magnet 25b moves to the lower part of the sleeve 25c, and the magnetic force of the magnet 25b and the sleeve 25c
The sleeve 25c is moved in the rotational direction by the rotational force of the sleeve 25c. The developer near the magnets 23b and 25b has a brush shape. The developer on the developing roller 25 is shaped by a doctor 26 provided at the end of the developer tank 7, and then approaches or contacts the electrostatic latent image surface of the photoreceptor 24, which is rotated in the direction of arrow d. Toner charged to a polarity opposite to that of the electrostatic latent image is applied to the electrostatic latent image by Coulomb force, and the electrostatic latent image is developed. The developed developer on the developing roller 25 is scraped off by the blade 27. The toner scraped off by the blade 27 and the toner dropped by the supply roller 3 are agitated by an agitation blade 28 disposed at the position where they fall.

In addition to the illustrated magnetic brush developing device, the toner supplying device of the present invention includes a cascade developing device that flows or cascades a developer consisting of toner and carrier onto the electrostatic latent image surface of a photoreceptor, and a rotating device that rotates while vibrating. A fur brush developing device that continuously supplies toner to a fur brush that has a mohair coating and contacts the electrostatic latent image surface of a photoreceptor by tapping the fur brush; A vibrating roller is used to dispense the toner, and then the toner is transferred from the supply roller to a velvet-covered pressure roller, which rotates while in contact with the electrostatic latent image surface of the photoreceptor. It can be applied to a dry developing device such as a developing device.

According to the present invention, since the first toner tank and the second toner tank are provided and the amount of toner stored in the first toner tank can be kept almost constant, the amount of toner supplied to the dry developing device can be reduced. In addition, since the toner agitating member and the toner transporting member are provided, blocking is less likely to occur, and since the amount of toner stored is relatively large, the number of times the toner tank is replenished from the outside with toner is small.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of the toner supply device of the present invention, FIG. 2 is a sectional view showing the configuration when the same device is used in a magnetic brush developing device, and FIG. 3 is a diagram showing the toner supply device of the present invention. FIG. 4 is a side view showing a transfer amount regulating member, and a perspective view showing a toner transfer member of the same device. 1...First toner tank, 2...Toner, 3
... Supply roller, 8 ... Second toner tank, 9
... Rotating rod, 11 ... Toner transfer amount regulating member, 1
2... Toner transfer member, 14... Toner stirring member, 15... Detection plate, 18... Sensor.

Claims (1)

[Claims] 1. A first toner tank having an outlet formed at the bottom and a toner inlet formed above the side, and a toner tank provided at the outlet at the bottom of the first toner tank to supply toner. a supply roller, a second toner tank whose lower part is connected to the toner inlet of the first toner tank, and a stirring member rotatably disposed within the first toner tank to stir the toner; A toner amount detection means for detecting the amount of toner in the first toner tank and a toner amount detection means disposed in the second toner tank detect that the toner amount is less than a certain value. the toner transfer means that is activated to transfer the toner to the first toner tank when the toner tank is activated, and the toner transfer amount regulating means that is provided at the connecting portion between the first toner tank and the second toner tank. A toner supply device characterized by: