JPS6315215Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a conveying device for powder such as toner, and in particular, to eliminate clogging of powder when conveying powder from one station to another. This invention relates to a powder conveying device that can convey powder smoothly.

[Prior art]

2. Description of the Related Art Conventionally, a powder conveying device as shown in FIG. 1 has been used in a copying machine or the like to convey toner from a toner storage section to a developing device, or to convey toner from a cleaning section to a developing section. FIG. 1 is a sectional side view of the main part of a powder conveying device, in which a spiral conveying member 2 is wound around a drive shaft 1 at an appropriate pitch and fixed to form a spiral roll.

The spiral roll is rotated within the pipe 3 for powder conveyance by a driving means (not shown), and the toner in the pipe 3 is discharged through a discharge port 4a formed in the reducing section coupling means 4 disposed near the end surface of the pipe 3. 7 to the next station.

The end of the drive shaft 1 is supported by a bearing 5 fitted in the reduction unit coupling means 4. 6 is a collar ring for preventing the drive shaft from coming off. The inner diameter of the pipe 3 is formed slightly larger than that of the conveying member 2 of the station so that there is a predetermined gap G, and the toner 7 is conveyed between the inner wall of the pipe 3 and the station.

[Problems with conventional technology]

According to the powder conveying device having the conventional structure described above, the toner 7 adheres to the spiral conveying member 2, making it impossible to convey the toner 7, and the toner does not fall at the discharge port 4a of the reducing unit coupling means 4. In order to prevent the toner 7 from adhering to such a spiral-shaped conveying member 2, it has been proposed that the surface of the conveying member be coated with Teflon (trademark), but this causes problems in high humidity and is insufficient as a conveying member. It is. Further, the toner 7 enters between the bearing 5 disposed in the reducing part coupling means 4 and the drive shaft 1 of the spiral roll, and unless the drive torque of the drive shaft is increased, it will not rotate, and in the worst case, it will not work due to torque overload. Causes harm. In addition, there is a distance l between the end 4b of the reducing unit coupling means 4 and the end of the discharge port 4a, and the toner 7 accumulated in this part increases the drive torque of the drive shaft, causing overload. There are also some drawbacks.

[Purpose of invention]

The present invention was devised in view of the above-mentioned drawbacks, and it is an object of the present invention to provide a powder conveying device in which toner does not adhere to the spiral roll conveying member, which does not cause clogging, and which does not overload the drive shaft. .

[Key points of the idea]

In order to achieve the above object, the present invention includes a powder conveying member having a spiral shape extending along the powder conveying direction, and a drive shaft that is rotatably supported and rotationally drives the powder conveying member. and a storage member that accommodates the powder conveyance member and the drive shaft and forms a powder conveyance path, in which the powder conveyance member has only one end connected to the drive shaft. The powder conveying member is fixed and the other end is a free end, and the drive shaft is loosely inserted through the powder conveying member along the longitudinal direction thereof.

[Example of idea]

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. 2 to 5. FIG. 2 is a plan view showing an embodiment of the part in which the powder conveying device of the present invention is used in a copying machine, and 10 is a photosensitive drum. is formed as a latent image on the circumferential surface of the photosensitive drum 10, and the latent image is visualized by the developing device 11 and transferred to transfer paper.
Although the transferred paper is not shown in FIG. 2, it is discharged to the outside of the copying machine via a fixing device. On the other hand, toner remaining on the surface of the photosensitive drum 10 is removed from the surface of the photosensitive drum 10 by a cleaner device 12. Generally, the toner transferred to the transfer paper at the transfer section is about 70 to 80% by weight of the toner attached to the photosensitive drum 10, and the remaining toner is stored in the cleaner device 12; Due to the problem of holding space and economic issues, the cleaner part coupling means 8 provided between the cleat device 12 and the pipe 3 of the conveyance means and the reducing part coupling means 4 provided between the developing device 11 and the pipe 3 of the conveyance means are used. Therefore, the stored toner in the cleaner device 12 is returned to the developing device 11 via the pipe 3 of the conveying means.
That is, in the cleaner device 12, toner collected by appropriate means is moved as indicated by the arrow and reused within the developing device 12.

FIG. 3 shows a side cross-sectional view of the inside of the pipe 3 of the conveying means shown in FIG. 2, and both ends of the pipe 3 constituting the conveying means are pivotally supported by the powder conveying device frame.
That is, the cleaner part coupling means 8 and the reducing part coupling means 4 are fitted. The cleaner part coupling means 8 has an opening 8a at its upper part, and the toner 7 stored in the above-mentioned cleaner device 12 falls through the opening 8a and is carried into the pipe 3 of the conveyance means. A bearing 5 is fitted on the side surface of the cleaner part coupling means 8,
A drive shaft 1 is rotatably fitted into the bearing 5, and a gear 9 is fixed to the drive shaft 1 which protrudes outward from the bearing 5 of the cleaner section coupling means 8, and is driven by a drive means (not shown). The force is transmitted to the gear 9 to drive the drive shaft 1 with a predetermined rotational force. Reference numeral 6 designates a flange ring similar to that shown in FIG. 1, and the reducing unit coupling means 4 is constructed in the same manner as shown in FIG. 1, and has a toner discharge port 4a at the lower end. It is formed so that it coincides with the end 4b of the inner surface of the side wall of the means 4 and does not have a distance l as shown in FIG. Furthermore, a holding part 4c for receiving the drive shaft 1 is integrally formed in the end 4b of the side wall of the reducing part coupling means 4 in a dish shape, so that the inner diameter of the holding part 4c is about 0.1 to 0.5 mm larger than the outer diameter of the drive shaft 1. Selected and loosely fitted. An enlarged side sectional view of this portion C is shown in FIG.

The drive shaft 1 is spanned between the bearing 5 of the cleaner section coupling means 8 and the holding section 4c of the reducing section coupling means 4, and is rotatably rotated by the drive means, and the spiral conveying member 2 is connected to the drive shaft 1. It is fixed to the drive shaft 1 in a cantilevered manner only on the upstream side where the toner is inserted and conveyed, and is in a free state at the other end (downstream side) on the discharge port 4a side.

Furthermore, since the diameter of the hole at the center of the spiral conveying member is selected to be larger than the diameter of the drive shaft 1, the tip of the conveying member 2 increases as the distance from the fixed end of the drive shaft 1 and the conveying member 2 increases. becomes free and comes into contact with the inner wall of the pipe 3 of the conveying means.

In a stationary state as shown in FIG. 3, the free end of the spiral conveying means 2 is in contact with the inner wall of the pipe 3 due to its own weight, but when rotational force is applied by the drive shaft 1, the outer diameter of the drive shaft 1 The free end of the conveying member 2 is swung within the size range of the difference between the diameter of the hole at the center of the spiral and the diameter of the hole at the center of the spiral.

To explain the operation in the above configuration, the opening 8
The toner falling from a is spiral rolled, that is, by the rotation of the drive shaft 1 and the conveying member 2, the toner is conveyed in the direction of the arrow along the spiral of the conveying member 2, and the toner is transferred from the discharge port 4a into the developing device 11. 7 is reduced. At this time, when the drive shaft 1 rotates, the toner 7 is moved in the direction of arrow B by the rotational force applied by the fixed part of the conveyance member 2, but as the outer diameter portion of the spiral conveyance member 2 moves toward the free portion at the tip, the toner 7 is moved in the direction of arrow B. Since it operates so as to be in contact with the inner wall of the pipe 3, unlike the conventional example shown in FIG. 1, there is no part where the toner is not conveyed in the gap G, so that the amount of movement of the toner 7 is large. In addition, the free portion of the conveying member 2 is shaken over most of its length with respect to the drive shaft 1, causing vibration every time it rotates, shaking off the toner that has adhered to the conveying member 2, and causing the toner to adhere to the conveying member 2. prevent this from happening.

In the present invention, since the drive shaft 1 passes through the center of the spiral-shaped conveyance member 2, the conveyance member 2 has almost no conveyance thrust to convey the toner 7 in the direction of arrow B compared to a case where the drive shaft 1 is not provided. The toner stirred by the central shaft portion can be effectively moved along the spiral of the conveying member, and the free end of the conveying member 2 can be prevented from flapping around without limit.

In the present invention, the outer diameter part of the conveying member 2 hits the inner wall of the pipe 3 every time it rotates, making it emit a sound, but in reality, when the toner is inserted into the pipe, the above-mentioned sound does not occur and the conveying member It has been confirmed that the outer diameter part of No. 2 does not hit the inner wall of the pipe and cause damage. Further, the holding portion 4c is attached to the reducing portion coupling means 4.
and set the hole diameter of the drive shaft 1 and the holding part 4c to 0.1 to 0.5.
Since the bearings are loosely fitted so that there is a gap K of mm, the toner 7 will not enter the bearing 5 and cause an overload condition as shown in FIG. That is, the drive shaft 1 and the holding part 4c
Even if toner gets into the hole span, there is no need to increase the torque of the drive shaft 1 since the tolerance is larger than the normal bearing tolerance. Furthermore, even if toner enters the holding portion 4c, it has a dish-shaped structure that does not leak to the outside, so that the inside of the copying machine will not be contaminated.

FIG. 5 shows another embodiment of the enlarged part C in FIG. It is designed so that it can slide inside. With this configuration, it is possible to further reduce the causes of increasing the torque of the drive shaft 1.

Furthermore, the end portion 4b of the reducing unit coupling means 4 and the discharge port 4a
As shown in Fig. 1, the toner 7 accumulated in the part indicated by l of the pipe
It is possible to reduce the increase in load due to

In the above embodiment, a conveying device for returning toner from a cleaning device to a developing device has been described, but it is obvious that the present invention is not limited thereto and can also be applied to a toner replenishing device.

[Effect of idea]

As mentioned above, according to the present invention, even if toner adheres to the conveying member, it can always be shaken off.
It is possible to provide a powder conveyance device that does not cause clogging of toner, which has great practical effects.

[Brief explanation of drawings]

FIG. 1 is a sectional side view of the main part of the conveying means of a conventional powder conveying device, and FIG. 2 shows an embodiment in which the powder conveying device of the present invention is used between a cleaning device and a developing device of a copying machine. A plan view, FIG. 3 is a side sectional view of the main part of the powder conveying device of the present invention shown in FIG. 2, FIG. 4 is an enlarged side sectional view of section C in FIG. 3, and FIG. It is an enlarged side sectional view showing another example of the enlarged part of C section similar to . DESCRIPTION OF SYMBOLS 1... Drive shaft, 2... Spiral-shaped conveyance member, 3... Pipe, 4... Reduction part coupling means, 4a
...Discharge port, 4b...End part, 4c...Holding part, 6
...Brim ring, 7...Toner, 8...Cleaner unit coupling means, 9...Gear, 10...Photosensitive drum, 11...
...Developing device, 12...Cleaning device.

Claims (1)

[Scope of utility model registration request] A powder conveying member having a spiral shape extending along a powder conveying direction, a drive shaft that is rotatably supported and rotationally drives the powder conveying member, and a drive shaft that rotates the powder conveying member and the drive shaft. In an apparatus for conveying powder such as toner, which includes a storage member that accommodates toner and forms a powder conveyance path, the powder conveyance member has only one end fixed to the drive shaft and the other end set as a free end;
A powder conveyance device characterized in that the drive shaft is loosely inserted into the powder conveyance member along the longitudinal direction.