JP2000214667A - Developer supply device - Google Patents

Abstract

(57) [Problem] To prevent clogging in a toner cartridge for supplying a toner having a low glass transition point for realizing low-temperature fixing for energy saving, to reduce the remaining amount of toner when replacing the toner cartridge, Economy is improved by lowering running costs. SOLUTION: A transport auger 18 in a toner supply area 16b of a toner cartridge 12 is S1 / L1 × 100.
≤80%, and the transport auger 18 in the toner transport area 16a
Is partly cut so as to satisfy 50% ≦ S2 / L2 × 100 ≦ 100%, thereby reducing the pressure of the toner and preventing the toner from being excessively supplied. (However, L1 is the total length of the supply port 17, S1 is the toner supply area 1
6b, the length of the portion where the transport spiral 18b is attached, L2 is the total length of the toner transport region 16b, and S2 is the length of the portion where the transport spiral 18b is attached in the toner transport region 16a.)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer supply device for transporting developer to a developing device using a transport auger in an electrophotographic apparatus or the like.

[0002]

2. Description of the Related Art Conventionally, as an exchangeable cartridge type developer supply device for supplying toner to a developing device using a two-component developer composed of toner and carrier such as an electrophotographic device, the developer is conveyed to the bottom of a housing. An apparatus is provided in which an auger is provided, the transport auger is rotated, the toner is transported to a supply port opened at the end of the housing, and the toner is dropped and supplied from the supply port to a developing device. In such a developer supply device, the rotation of the transport auger is controlled to be on or off in accordance with a detection result from a density detection device that detects a mixture ratio of toner and carrier in the development device with a sensor. Alternatively, a predetermined amount of toner is stably supplied to the developing device by controlling the rotation speed.

[0003]

However, in the case of a developer supply device in which toner is transported by a transport auger and supplied from a supply port at the end of the housing, the toner is transported to the supply port at the end of the housing. In the vicinity of the supply port located at the leading end of the transport auger in the transport direction, the toner is mechanically or thermally stressed by the pressure from the sequentially transported toner, so that the toner aggregates and adheres to the auger. And clogging is likely to occur. If the toner is clogged due to agglomeration, the supply amount of toner does not reach the required amount, and the image is blurred and the display quality is deteriorated despite the rotation control of the transport auger according to the detection result of the density sensor. The problem of lowering has occurred.

Further, since toner is not supplied to the developing device due to clogging even though toner remains in the housing, it is determined that the developer supplying device is empty, and the replacement thereof is displayed. In addition, the developer supply device must be replaced before the toner is effectively consumed, and the number of developing units per cartridge of the developer supply device is reduced, which causes a problem that the running cost is increased.

In particular, with the recent promotion of energy saving,
In copiers, printers, and the like, it is required to lower the fixing temperature, and in order to achieve this, development of a toner that can be fixed at a lower temperature is required. Since toner that can be fixed at such a low temperature generally uses a resin that is easily melted at a low temperature, toner aggregation occurs due to mechanical or thermal stress due to the pressure of the toner in the developer supply device. Easily, clogging due to toner aggregation near the supply port during transport by the transport auger occurs quickly,
When the developer supply device is replaced, the remaining amount of toner becomes large, and the number of developed sheets per cartridge is further reduced, resulting in a problem of poor economic efficiency.

Accordingly, the present invention has been made to solve the above-described problem, and it is possible to prevent the toner from aggregating and clogging in the vicinity of a supply port irrespective of the pressure of the toner while the toner is being transported by the transport auger. It is an object of the present invention to provide a developer supply device that stably supplies the toner stored in the developer supply device to the end, reduces running costs, improves economy, and obtains good image quality. .

[0007]

According to the present invention, as a means for solving the above-mentioned problems, there is provided a storage portion for storing a developer,
A housing extending from the storage section to the front end of the developer in the direction of transport of the developer at the bottom of the storage section and including a developer supply mechanism having a developer transport area and a developer supply area; A supply port that is opened at the bottom of the developer supply area and supplies the developer in a dropping manner, and a transport spiral is attached to the outer periphery of the rotating shaft in a spiral shape, and extends from the storage section to the developer supply mechanism at the bottom of the housing. A developer supply device provided with a transport auger for transporting the developer to the supply port, wherein a part of the transport spiral positioned at the developer supply mechanism is cut.

According to another aspect of the present invention, there is provided a container for storing a developer, and a developer conveyer extending from the container to a leading end of the developer in the conveying direction at the bottom of the container. A housing formed of a developer supply mechanism having an area and a developer supply area; a supply port opened at the bottom of the developer supply area of the developer supply mechanism and configured to supply the developer by dropping; A transport auger provided with a transport spiral attached to the developer supply mechanism at the bottom of the housing from the storage section to transport the developer to the supply port.
Assuming that the total length of the supply port is L1 and the length occupied by the transport spiral in L1 is S1, the following equation (1): S1 / L1 × 100 ≦ 80% The transport spiral is cut, and the entire length of the developer transport area is set to L.
2. The length occupied by the transport spiral in L2 is S2
In this case, the transport spiral positioned in the developer transport area is cut so that 50% ≦ S2 / L2 × 100 ≦ 100%.

According to the present invention, the present invention reduces the toner pressure by partially cutting off the conveying spiral of the auger located in the developer supply mechanism, prevents the toner from aggregating and adhering to the auger, The purpose of the present invention is to reduce the amount of toner remaining at the time of replacement of the agent supply device, and to improve the economic efficiency by reducing the running cost. Further, by adjusting the cut amount of the transport spiral located in the developer supply area and the cut amount of the transport spiral located in the developer transport area, the toner supply amount is stabilized, and a developed image having good display quality can be obtained. What you get.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, in order to prevent toner agglomeration occurring near a supply port in a developer supply device, a part of a transfer spiral of a transfer auger near a supply port is cut.
This is to reduce the mechanical or thermal stress applied to the toner near the supply port due to the pressure of the toner sequentially conveyed while expanding the volume of the hollow portion near the toner supply port. However, if the transport spiral of the transport auger is cut too much,
The transport auger cannot maintain the transport adjustment function, the toner supply amount is increased more than necessary, and the excessive supply of the toner causes insufficient mixing of the toner and the carrier. Therefore, the cut amount of the transport spiral is adjusted to stabilize the toner supply.

An embodiment of the present invention will be described below with reference to FIGS.
This will be described with reference to FIG. FIG. 1 shows a toner cartridge 12 that is a developer supply device that supplies a toner 11 that is a developer to a toner inlet 10a of a developing device 10 that performs magnetic brush development using a two-component developer including a toner and a carrier. Show. The toner cartridge 12 has stirring blades 14 for stirring the toner 11 in the toner storage unit 13, and a toner supply mechanism 16 including a toner transport region 16 a and a toner supply region 16 b is provided at an end of the toner storage unit 13. Is formed. Between the toner storage unit 13 and the toner supply mechanism 16, the toner 11 in the toner storage unit 13 is supplied to the supply port 1 formed in the toner supply area 16 b.
A transport auger 18 for transporting in seven directions is provided. The supply port 17 is inserted through the injection port 10a of the developing device 10.

The transport auger 18 is configured to perform on / off control of driving in accordance with a detection result from a toner density sensor (not shown) of the developing device 10. The transport auger 18 includes a rotating shaft 18a and a transport spiral 18b spirally attached to the outer periphery thereof.

In the toner supply area 16b,
When the total length of the supply port 17 is L1, a part of the transport spiral 18b is cut so that the length of the portion of the L1 to which the transport spiral 18b is attached is S1, and a free space is provided in the toner supply area 16b. R1 is formed. Here, “Equation 3” S1 / L1 × 100% is defined as a free volume ratio.

In the toner transport region 16a, when the total length of the toner transport region 16b is L2, the length of the portion of the transport spiral 18b to which the transport spiral 18b is attached is L2. A portion is cut to form a free space R2 in the toner transport region 16a. Here, “Equation 4” S2 / L2 × 100% is defined as the auger occupancy.

Next, a toner cartridge 12 from which a part of the transport spiral 18b of the transport auger 18 is cut is mounted on a copying machine DP3580 manufactured by Toshiba, and a supply port is provided when the toner 11 is supplied to the developing device 10. The determination of a test for checking clogging, excessive supply of toner, and insufficient supply of toner at 17 will be described. Each test was conducted using a chart in which the area of the character portion occupies 8% of the whole in A4 size.
It is performed by copying 100,000 sheets.

(1) Clogging at Supply Port With regard to clogging at the supply port 17, toner 1/10 or more of the toner filling amount is contained in the replaced toner cartridge 12 according to the indication of replacement of the toner cartridge 12. If the toner cartridge 12 remains, the remaining toner amount is set to x (large), and it is determined that clogging has occurred.
When the remaining toner amount at the time of replacement is 1/10 or less of the toner filling amount, the remaining toner amount is set to ○ (small), and it is determined that clogging does not occur.

(2) Excessive Supply of Toner Regarding excessive supply of toner 11, if the fog of the developed image is 1.5% or less, it is determined to be （(no fog).
If it is 5% or more, it is determined to be x (with fog).

(3) Insufficient supply of toner Regarding the insufficient supply of toner 11, the blur of the developed image is measured using a Macbeth densitometer, and the image density becomes 1.00.
If it is more than the above, it is determined to be （(no blurring), and if it is 1.00 or less, it is determined to be × (there is blurring).

Next, an example of the above embodiment will be described.

(Embodiment 1) In this embodiment, one of the transport spirals 18b in the toner supply area 16b is adjusted so that the free volume ratio defined by "Equation 3" S1 / L1 × 100% becomes 80%. A free space R1 is formed in the toner supply region 16b by cutting the portion, and the transport spiral 18b in the toner transport region 16a is adjusted so that the auger occupancy defined by “Equation 4” S2 / L2 × 100% becomes 75%. Is cut to form a free space R2 in the toner transport region 16a.

Further, as the resin component, a copolymer of styrene and a substituted product thereof, an acrylic resin and the like, which have been conventionally used as a binder resin for a developer, can be used. Specific examples of the copolymer of styrene and its substituted product include, for example, polystyrene homopolymer, hydrogenated styrene resin, styrene-isobutylene copolymer, styrene-butadiene copolymer, acrylonitrile-butadiene-styrene terpolymer. Acrylonitrile-styrene-acrylic ester terpolymer, styrene-acrylonitrile copolymer, acrylonitrile-acrylic rubber-styrene terpolymer, acrylonitrile-chlorinated polystyrene-styrene terpolymer, acrylonitrile-EVA- Styrene terpolymer, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer,
Examples thereof include styrene-butadiene rubber, styrene-maleic acid ester copolymer, styrene-isobutylene copolymer, and styrene-maleic anhydride copolymer.

As the acrylic resin, for example,
Polyacrylate, polymethyl methacrylate, polyethyl methacrylate, poly-n-butal methacrylate, polyglycidyl methacrylate, polyfluorinated acrylate, styrene-methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-ethyl acrylate copolymer Coalescence and the like are exemplified.

In addition, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin, phenol resin, urea resin, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic Alternatively, a toner 11 made of an alicyclic hydrocarbon resin, an aromatic petroleum resin, chlorinated paraffin, paraffin wax or the like and having a glass transition point of 65 ° C. is used.

The toner cartridge of Example 1 was mounted on a copying machine DP3580 manufactured by Toshiba, and a test was conducted. As a result, no clogging occurred in the supply port 17 as shown in Table 1. In addition, the remaining amount of toner when the toner cartridge 12 is replaced is small, the number of developed sheets per cartridge is increased by the effective use of the toner 11, and the economic efficiency can be improved by reducing the running cost. In addition, the toner supply condition was good, and there was no fogging of an image due to excessive toner supply or blurring due to insufficient toner supply, and high display quality was obtained.

(Embodiment 2) In this embodiment, the free volume ratio defined by “Equation 3” S1 / L1 × 100% is the same as that of (Embodiment 1), and “Equation 4” S2 / A part of the transport spiral 18b in the toner transport area 16a is cut to form a free space R2 in the toner transport area 16a so that the auger occupancy defined by L2 × 100% becomes 50%.

The same toner 11 as in the first embodiment is used.

The toner cartridge of (Example 2) was mounted on a copying machine DP3580 manufactured by Toshiba, and a test was conducted. As a result, as shown in (Table 1) as in (Example 1), the toner at the supply port 17 was changed. There was no clogging, and economic efficiency could be improved by reducing running costs. Further, the toner supply condition was good, and high display quality was obtained.

(Embodiment 3) In this embodiment, the free volume ratio defined by “Equation 3” S1 / L1 × 100% is the same as in (Embodiment 1).
The auger occupancy defined by “Equation 4” S2 / L2 × 100% is set to 100% without cutting the transport spiral 18b in the toner transport area 16a.

As the toner 11, the same toner as in the first embodiment is used.

The toner cartridge of (Example 3) was mounted on a copying machine DP3580 manufactured by Toshiba, and a test was conducted. As a result, as shown in (Table 1) as in (Example 1), the toner at the supply port 17 was changed. There was no clogging, and economic efficiency could be improved by reducing running costs. Further, the toner supply condition was good, and high display quality was obtained.

(Embodiment 4) In the present embodiment, all the transport spirals 18b in the toner supply area 16b are set so that the free volume ratio defined by "Equation 3" S1 / L1 × 100% becomes 0%. While cutting, the conveying spiral 18b in the toner conveying area 16a is not cut, and the auger occupancy defined by “Equation 4” S2 / L2 × 100% is set to 100%.

The same toner 11 as in the first embodiment is used.

The toner cartridge of (Example 4) was mounted on a copying machine DP3580 manufactured by Toshiba and a test was conducted. As a result, as shown in (Table 1) of (Example 1), the toner at the supply port 17 was changed. There was no clogging, and economic efficiency could be improved by reducing running costs. Further, the toner supply condition was good, and high display quality was obtained.

(Embodiment 5) In this embodiment, the free volume ratio defined by “Equation 3” S1 / L1 × 100% is the same as in (Embodiment 1).
The auger occupancy defined by “Equation 4” S2 / L2 × 100% is set to 100% without cutting the transport spiral 18b in the toner transport area 16a.

A toner 11 having a glass transition point of 55 ° C., which is made of a styrene-acrylic resin as a resin component, is used.

The toner cartridge of (Example 5) was mounted on a copying machine DP3580 manufactured by Toshiba, and a test was conducted. As a result, as shown in (Table 1) as in (Example 1), the toner at the supply port 17 was changed. There was no clogging, and economic efficiency could be improved by reducing running costs. Further, the toner supply condition was good, and high display quality was obtained.

Next, a comparative example will be described with reference to FIG. The toner used in the toner cartridge 22 of this comparative example differs from that of the above-described embodiment, or the cut amount of the transport spiral 24b around the transport auger 24 in the toner transport area 26a and the toner supply area 26b is different.

(Comparative Example 1) In this comparative example, a part of the transport spiral 24b in the toner supply area 26b is cut so that the free volume ratio defined by “Equation 3” S1 / L1 × 100% becomes 85%. Then, a free space R1 is formed in the toner supply area 26b, and a part of the transport spiral 24b in the toner transport area 26a is set so that the auger occupancy defined by “Equation 4” S2 / L2 × 100% becomes 75%. To form a free space R2 in the toner transport area 26a.

A styrene / acrylic resin having a glass transition point of 65 ° C. is used as the resin component.

(Comparative Example 2) In this comparative example, a part of the transport spiral 24b in the toner supply area 26b is cut so that the free volume ratio defined by “Equation 3” S1 / L1 × 100% becomes 80%. Then, a free space R1 is formed in the toner supply area 26b, and a part of the transport spiral 24b in the toner transport area 26a is set such that the auger occupancy defined by “Equation 4” S2 / L2 × 100% becomes 45%. To form a free space R2 in the toner transport area 26a.

The glass transition point of Comparative Example 2 was 65
Use a toner of ° C.

(Comparative Example 3) In this comparative example, the transport spiral 24b in the toner supply area 26b and the transport spiral 24b in the toner transport area 26a are not cut, and "Equation 3" is calculated as S1 / L1 × 100%. The defined free volume ratio is set to 100%, the auger occupancy defined by “Equation 4” S2 / L2 × 100% is also set to 100, and the styrene-acrylic resin is used as a resin component, and the glass transition point is set. Uses a toner of 70 ° C.

For these (Comparative Examples 1) to (Comparative Example 3), a copying machine D manufactured by Toshiba
As a result of a test of the toner cartridge mounted on the P3580, as shown in Table 1, in Comparative Example 1, the free volume ratio of the toner supply region 26b was large and the free space R1 was small. Then, pressure was applied to the toner, and the toner was aggregated, clogging occurred in the toner supply area 26b, and the image was blurred due to insufficient toner supply, and the display quality was degraded. At the same time, the amount of toner remaining when the toner cartridge 22 is replaced is large, and the number of developed sheets per cartridge is reduced. Also, in (Comparative Example 2), the toner transport area 2
6a has a small auger occupancy, and the toner is excessively supplied, causing fog on the image and deteriorating the display quality.

(Comparative Example 3) shows the toner supply area 26b.
Also, the transport spiral 24b is not cut in any of the toner transport areas 26a and the free spaces R1 and R2 are not formed at all. However, since the glass transition point of the toner is as high as 70 ° C., pressure is applied to the toner. Regardless, the toner is hardly agglomerated, the toner does not adhere to the transport auger 24, and the clogging does not occur. As a result, good display quality can be obtained, and further, the economic efficiency can be improved by reducing the running cost.

[Table 1] From the above results, in the present embodiment, the toner 11
Has a low glass transition point of 65 ° C. and the toner 11 is easily melted at a low temperature, it is necessary to prevent the toner from agglomerating, eliminate clogging, and perform good toner supply.
When 1 is the total length of the supply port 17 and S1 is the length of the portion where the transport spiral 18b is attached in the toner supply area 16b, the following equation is obtained. S1 / L1 × 100 ≦ 80% When L2 is the entire length of the toner transport area 16b and S2 is the length of the portion where the transport spiral 18b is attached in the toner transport area 16a, a part is cut, "Equation 2" 50% ≦ S2 / L2 × It has been found that it is only necessary to cut a part of the transport spiral 18b so that 100 ≦ 100%.

According to this structure, the toner transport area 16a despite the low glass transition point of the toner 11
By cutting a part of the transport spiral 18b in the toner supply area 16b to form free spaces R1 and R2, respectively, the pressure applied to the toner 11 near the supply port 17 can be reduced, and the mechanical force applied to the toner 11 can be reduced. Alternatively, thermal stress can be reduced to prevent the toner 11 from aggregating and adhering to the transport auger 18 to cause clogging. Therefore, the toner in the toner storage section 13 can be supplied to the end, and the number of developed sheets per cartridge can be increased, so that the running cost can be reduced and the economic efficiency can be improved. Further, blurring of an image due to insufficient toner supply can be prevented, and display quality can be improved. In addition, the cut amount of the transport spiral 18b in the toner transport area 16a is less than 50% of the entire length of the toner transport area 16a, which prevents the toner 11 from being excessively supplied. As a result, no fogging occurs in the image, and a good display quality without fogging can be obtained.

The present invention is not limited to the above-described embodiment, but can be variously modified. If the glass transition point is 65 ° C. or lower, the resin material used for the toner is not limited. Is also good.

[0047]

As described above, according to the present invention, even if the glass transition point is as low as 65 ° C. or less and the developer is easily melted at a low temperature, clogging due to agglomeration occurs during the transportation and supply of the developer. This eliminates the occurrence of blurring, prevents blurring of the developed image, obtains good display quality, reduces the amount of developer remaining in the developer supply device, allows the developer to be consumed efficiently, and reduces running costs. Can improve economic efficiency. Further, by preventing the excessive supply of the developer, it is possible to prevent the charging failure of the developer caused by the excessive supply, thereby preventing the image from fogging, obtaining a good display quality, and saving the apparatus by lowering the fixing temperature. Energy can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a toner cartridge according to an embodiment of the present invention as viewed from the front.

FIG. 2 is a schematic explanatory view showing the toner cartridge according to the embodiment of the present invention as viewed from a side.

FIG. 3 is a schematic explanatory view showing a transport auger in the toner supply mechanism according to the embodiment of the present invention.

FIG. 4 is a schematic explanatory view showing a transport auger in a toner supply mechanism of a comparative example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 developing device 11 toner 12 toner cartridge 13 toner storage unit 14 stirring blade 16 toner supply mechanism 16 a toner transport region 16 b toner supply region 17 supply port 18 transport auger 18 a rotating shaft 18 b transport spiral

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuo Higashihata 70, Yanagicho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Tec Image Information Systems Co., Ltd. K Image Information System Co., Ltd. (72) Inventor Kenji Tanaka 70 Yanagimachi, Saiwai-ku, Kawasaki City, Kanagawa Prefecture Toshiba Tec Image Information System Co., Ltd. F-term (reference) 2H077 AA02 AA25 AB03 AB07 AC02 BA09 EA03

Claims (3)

[Claims] And a developer supply mechanism that has a developer transport area and a developer supply area that extend from the storage section to a front end of the developer in a transport direction of the developer at a bottom of the storage section. And a supply port opened on the bottom surface of the developer supply area of the developer supply mechanism and supplied to drop the developer, and a transport spiral spirally attached to the outer periphery of the rotating shaft,
A developer auger provided at the bottom of the housing from the storage section to the developer supply mechanism for transporting the developer to the supply port, wherein the transporter located at the developer supply mechanism is provided. A developer supply device characterized by cutting a part of a spiral. 2. A developer storage mechanism for storing a developer, and a developer supply mechanism extending from the storage part to a front end of the developer in a transport direction of the developer at a bottom of the storage part and having a developer transport region and a developer supply region. And a supply port opened on the bottom surface of the developer supply area of the developer supply mechanism and supplied to drop the developer, and a transport spiral spirally attached to the outer periphery of the rotating shaft,
A developer auger provided at the bottom of the housing from the storage section to the developer supply mechanism for transporting the developer to the supply port, wherein the total length of the supply port is L1, L1. When the length occupied by the transport spiral in the area is defined as S1, the transport spiral positioned in the developer supply area is cut such that S1 / L1 × 100 ≦ 80%, and the developer transport is performed. L is the total length of the region
2. The length occupied by the transport spiral in L2 is S2
In the developer supply device, the transport spiral positioned in the developer transport area is cut so that “Equation 2” is 50% ≦ S2 / L2 × 100 ≦ 100%. 3. The developer supply device according to claim 1, wherein a glass transition point of the developer stored in the storage section is 65 ° C. or less.