JPS60221779A - Toner replenishing device - Google Patents

Abstract

PURPOSE:To prevent adhesion of toner to a sensor and to maintain stable detecting action by attaching a toner remainder sensor on the inner wall of a hopper, providing a vibrating plate on the side of the sensor and slidably engaging its an end with a screw coil. CONSTITUTION:An electrostriction vibrator sensor 25 that detects remainder of toner is provided on the inner wall of lower part of a toner hopper. A vibrating plate 26 is mounted to the side of the sensor 25 through a sponge seal 27, and a bent piece of the vibrating plate 26 is slidably engaged with a screw coil 5. Accordingly, when the screw coil 5 is rotated, disengagement and returning action by elastic force of the bent piece are repeated and the vibrating plate 26 vibrates periodically. The vibration is transmitted to the sensor 25 and the adhered toner is sprung off. Thus, the adhesion of toner to the sensor 25 is prevented, and the stable detecting action can be maintained avoiding malfunction.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a toner replenishing device used in an electrostatic copying machine that performs dry development. □Conventional structure and problems thereof Conventional dry electrophotographic copying machine A toner replenishing device generally has a toner remaining amount sensor disposed on the lower inner wall of a toner hopper having a toner replenishing roller in its lower opening, and is configured to detect the presence or absence of toner contained in the toner hopper. ing.

Then, the toner remaining amount sensor senses the change in toner pressure, identifies whether the toner is above or below the sensor surface, and if it is below, displays an indication that the toner amount is low. That's what I do.

However, since toner has properties that make it easy to stick and stick, if toner adheres to the surface of the remaining toner amount sensor, or if it hardens after adhesion, the toner will be consumed and the surface will be lower than the sensor surface. There is a drawback that even if the amount of toner remaining is reduced to 1, there is no indication that the remaining amount of toner is low. For this reason, if you continue to use the device, the toner in the developing device will run out, and it is only when the image becomes lighter that you realize that there is no more toner in the toner hopper. It had the disadvantage of not being able to do so.

Purpose of the Invention The present invention aims to eliminate the drawbacks of the above-mentioned conventional example, and stably maintains the detection function of the remaining toner amount sensor.
SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a hopper having an opening for toner replenishment at the bottom, and a toner replenishing device disposed within the hopper. A screw coil for stirring and transferring toner and an electrostrictive vibrator sensor disposed on the inner wall of the hopper, one side of which is close to the electrostrictive vibrator sensor, and the other part of the screw coil that is close to the screw coil. The present invention is constructed by comprising a diaphragm arranged so as to be slidably engaged.Description of Embodiments The present invention will be explained below based on the illustrated embodiments. An overall perspective view of the toner replenishing device, FIG. 2 is a cross-sectional plan view taken along line A-A, FIG. 3 is a cross-sectional plan view taken along line B-B, and FIG. 4 is a cross-sectional view taken along lines a and -C. .

In these figures, reference numeral 1 denotes a hopper in which magnetic toner 2 is stored, which has a toner filling opening and is composed of a vertical first storage section 1& and a horizontal second storage section 1b.

Reference numeral 3 designates a rotating lid that opens and closes the toner filling opening above the first storage portion of the hopper, and 4 designates an upper lid that seals the second storage portion 1b of the hopper 1. 5 is a right-handed helical screw coil, one end of which is press-fitted into the boss 6, and the other end is an impeller-shaped screw coil with four protrusions on the outer periphery as shown in Fig. 4.
It is inserted into the 7-pu 7. The boss 6 and the sleeve 7 are
Both ends of the storage portion 1b are fixed to a rotating shaft 8 which is rotatably supported on the side wall of the storage portion 1b, so that the storage portion 1b rotates together with the screw coil 5. 9 indicates an oil seal. 1o is a rectangular plate-shaped rotating blade made of an elastic member such as rubber or plastic whose one end is fixed to one side of the rotating shaft 8 with a screw or the like, and when the other end rotates, the second storage section 1. It has a length that reaches the bottom wall of the container, and is configured to scoop up the magnetic toner 2 at the bottom. The rotating shaft 8 is rotated counterclockwise by a drive system to be described later, and the screw coil 5 is configured to transport the magnetic toner in the direction of the arrow. Here, the outer diameter of the rotating shaft 8 is smaller than the inner diameter of the screw coil 6, and a gap is formed between the rotary shaft 8 and the screw coil.

Similarly, 11 is a left-handed helical screw coil, 12
13 is a boss, 13 is a sleeve, 14 is a rotating shaft, and 15 is a rotating blade, which is configured exactly the same as the above-mentioned screw coil 6, boss 6, sleeve 7, rotating shaft 8, and rotating blade 10, but in the opposite direction. It is arranged. The rotating shaft 14 is rotated counterclockwise by a drive system, which will be described later, so that the screw coil 11 transports the magnetic toner in the direction of arrow E. Therefore, when the rotating shafts 8 and 14 rotate counterclockwise, the magnetic toner is transferred to the screw coil 5, respectively.
and 11, it is transferred in the arrow direction and the E direction. At the same time, the rotary vanes 10 and 15 disposed at the ends in the opposite direction are also rotating, so the magnetic toner sent in the direction D is transferred by the rotary vane 10 in the direction of arrow F, and the magnetic toner sent in the direction of arrow E is The toner is transported perpendicularly to the direction of the arrow G by the rotating blades 16 and delivered to the opposing screw coils 11 and 6.

As described above, since the magnetic toner is transferred while being stirred by the screw coil and the rotating blade in the second storage section 1b, assimilation of the magnetic toner in the hopper can be prevented.

Providing a gap between the screw coil and the rotating shaft to give fluidity to the magnetic toner even between the screw coils of one pitch also has a more effective effect. ・16 is the replenishment roller, and the screw It is rotatably disposed parallel to the coil and at the substantially central bottom of the second storage section 1b. In this embodiment, a recess corresponding to the length of the replenishment roller 16 is formed at the bottom between the screw coils, and a slight gap is provided between the replenishment roller and the replenishment roller. A slit-shaped opening or a plurality of elongated openings H for supplying magnetic toner to a developing device (not shown) is formed in this recessed portion.

4. Magnets 17, such as rubber magnets, are provided on both shoulders of this recess over the entire length, as shown in FIG.

The magnet 17 is an anisotropic type permanent magnet, with N-
It is magnetized with fls, and as shown in FIG. 6, it is arranged so that the point where the lines of magnetic force are concentrated is located on the replenishment roller 16 side. Therefore, a magnetic curtain is formed between the replenishment roller 16 and the magnet 17 due to the concentration of magnetic lines of force, and the magnetic toner is attracted to the magnet 17, forming a magnetic toner seal between the replenishment roller 16 and the developer. It will not leak to the sides.

The replenishment roller 16 has a flat portion 16a formed with a part of its outer periphery cut out in the axial direction, and when the replenishment roller 16 rotates once, the magnetic toner adhering to the magnet 17 is scraped off by this flat portion. Drop it through the opening H at the bottom of the fourth part and replenish it to the developing device.

By disposing anisotropic type magnets in which lines of magnetic force are concentrated at the tip on both shoulders of the bottom recess of the second storage section 1b facing the replenishment roller, magnetic toner is drawn from the gap between the replenishment roller and the replenishment roller by the action of the lines of magnetic force. Natural fall can be prevented, and furthermore, by increasing the magnetic force, the gap between the replenishment roller and the inner wall of the recess can be designed to be large, thereby preventing the inability to replenish the magnetic toner due to an increase in the rotational load of the replenishment roller 16.

18 is a gear pivotally supported by the rotating shaft 8, 19 is a gear pivotally supported by the rotating shaft 14, and power from a drive source (not shown) is transmitted to the driving gear 20. It is designed to be driven via a transmission gear 21. 22 is an intermediate gear, which controls the rotation of gear 19 from gear 1.
8, and is rotatably supported on the shaft of the supply roller 16. 23 is pivotally supported by the shaft of the supply roller 16,
Power from a drive source (not shown) is transmitted by a drive gear 24.

The replenishing rollers 16 are controlled by a control system to normally rotate clockwise and to stop after each rotation. Note that the rotation may be stopped every several rotations depending on the amount of replenishment, and this can be selected freely.

25 is a sensor that detects the remaining amount of magnetic toner.
In this embodiment, an electrostrictive vibrator is used and is disposed on the inner wall of the second storage portion 1b with the sensor surface facing inward.

26 is plastic such as polyester film.

Sensor 2 is a diaphragm made of elastic material such as rubber or metal plate.
It is arranged close to 5.

As shown in FIG. 7, a bent piece 26a is formed on the diaphragm 26, and the - side is attached to the sensor 25 via a sponge seal 27, and the bent piece 26a is slidably connected to the screw coil 5. It is engaged. Note that the diaphragm 26 may be directly attached without using the sponge seal 27.

When the screw coil 5 rotates, the bent piece 26a is bent in the direction of the arrow. However, when the screw coil 5 rotates further, it becomes uncoupled and returns in the direction of arrow E by elastic force, and this operation is reversed at the end of the rotation of the screw coil 5. Therefore, the diaphragm 26 vibrates periodically, this vibration is transmitted to the sensor 25, and the magnetic toner adhering to the sensor surface is repelled. This action removes the magnetic toner adhering to the sensor surface, eliminating the problem of the sensor detecting the presence of magnetic toner even though there is almost no magnetic toner in the hopper due to adhesion of magnetic toner. Therefore, the sensor stably performs the remaining amount detection operation, and the problem of a decrease in image density due to insufficient supply of magnetic toner can be prevented.

Reference numeral 28 denotes a regulating sheet such as a plastic film or thin plate made of polyester or the like, which is disposed on the inner wall of the first storage portion 1a of the ompper 1. The lower opening communicating with the first storage section 1ρ and the second storage section 1b is formed with a width that is large enough to overlap the rotating blade 15 fixed to the magnetic toner population side end of the rotating shaft 14 and one end of the screw coil 5. has been done. As shown in FIG. 2, the regulation sheet 28 has a length that covers the entire diameter of the screw coil 5 from the right end of the opening of the first storage section 1a, and is slightly narrower than the width of the first storage section. It has a width.

This regulation sheet 28 prevents the magnetic toner in the first storage section 1a from being directly transferred by the screw coil 5.

Here, the function of the regulation sheet 28 will be further explained using FIG. 8. Figure 8 shows the amount of magnetic toner and the rotation axis 8.
, 14, the curve A indicates the case where the regulation sheet 28 is not provided, and the curve A indicates the case where the regulation sheet 28 is provided. As is clear from the figure, in the case of curve A, when the amount of magnetic toner in the hopper 1 increases by 2α, the load torque increases rapidly and εα
When it becomes so, it exceeds 9 to 9 cm. This is the second storage part 1
Although there is a sufficient amount of magnetic toner inside b, the magnetic toner that has been agitated and transferred by the rotary blade 15 is transferred to the screw coil 5 on the right side in the perpendicular direction, and the screw coil 6 is directly transferred to the first screw coil 5. This is because the magnetic toner inside the storage section 1& is being compressed and a large force is required to feed the magnetic toner to the inner side. On the other hand, when the regulation sheet 28 is disposed above the screw coil 5, the screw coil 5 only needs to send the magnetic toner transferred by the rotating blade 16, so that the load torque does not increase much as in the case of a curved opening.

Next, the operation of the above embodiment of the present invention will be explained.

When the rotary lid of the hopper 1 is opened and the magnetic toner 2 is stored in the first storage portion 1a, and a drive source (not shown) is driven, the rotation shafts 8 and 14 are rotated counterclockwise.

The magnetic toner 2 is transferred to the screw coil 5 by the rotating blade 15.
sent inside. The magnetic toner is moved in the direction of the arrow F by the screw coil 5, and when it reaches the rotating blade 1o, it is sent in the direction of the arrow F. The magnetic toner that has reached the boss 12 is sent in the direction of arrow E by the rotation of the screw cobble 11.

Through the above-described operations, the magnetic toner is stored in the second storage section 1b and is constantly circulated within the second storage section 1b. 1st
The magnetic toner placed in the storage section 1a moves to the second storage section 1b, but when a predetermined amount is reached, the toner regulating sheet 28 and the second storage section 1b move in the direction of arrow G. Since the size surrounded by the bottom of the inlet is the size of the inflow port, magnetic toner exceeding a predetermined amount will not enter the screw coil 6. When replenishing the magnetic toner 2, a drive source (not shown) is moved to drive the connecting gears 23 and 24 to rotate the replenishment roller 16 once in the clockwise direction, and a predetermined amount of the magnetic toner 2 is deposited into the second storage portion 1b. It falls from the opening at the bottom into a developing section (not shown).

Although the above embodiments of the present invention have been described using magnetic toner as an example, the toner is not limited to this, and the same effect can be obtained even if an insulating toner is used.

Effects of the Invention As detailed above, according to the present invention, the toner sensor is vibrated by the vibrating member provided on the side surface of the toner sensor, and the toner near the toner sensor is periodically shaken, so that the sensor of the toner sensor Toner no longer adheres to the surface9, and the operation to detect the amount of toner in the toner storage section works stably.In addition, since the detection of the amount of toner in the toner storage section works stably, the problem of reduced image density due to lack of toner does not occur. Therefore, it is possible to obtain an excellent effect that a dry type developing device with stable image quality can be realized.

[Brief explanation of the drawing]

FIG. 1 is an overall perspective view of the toner replenishing device according to the present invention, FIG. 2 is a cross-sectional plan view taken along the line A-A, FIG. 3 is a cross-sectional view taken along line C-C, and FIG. 5 is an enlarged perspective view of the essential parts of the bottom of the hopper in the embodiment of the present invention, FIG. 6 is the same sectional view, and 7M is a cross-sectional view of the hopper according to the embodiment of the present invention.
1 is a characteristic diagram showing the relationship between the drive load torque of the rotating shaft; FIG. 1...Hopper, 1°°°°°first storage section,
1b"°"° 2nd storage section, 6.11 Old... Screw coil, 8°14... Rotating shaft, 10.15...
... Rotating vane, 16 ... Supply roller, 17
...Magnet, 26...Sensor, 26.
...Diaphragm, 26a'...Bent piece, 28.
...Regulation sheet, H...Opening. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4 Figure ?

Claims (1)

[Claims] A hopper having an opening for toner replenishment at the bottom, a screw coil disposed within the hopper for agitating and transferring toner, an electrostrictive vibrator sensor disposed on the inner wall of the hopper, and the electrostrictive vibrator. A toner replenishing device comprising a diaphragm having one side close to the sensor and the other side slidingly engaged with the screw coil.