WO2011131107A1

WO2011131107A1 - Cartridge

Info

Publication number: WO2011131107A1
Application number: PCT/CN2011/072876
Authority: WO
Inventors: 高瑞祺; 杨晓锋; 周宏辉
Original assignee: 珠海天威飞马打印耗材有限公司
Priority date: 2010-04-20
Filing date: 2011-04-15
Publication date: 2011-10-27
Also published as: CN101887231A

Abstract

A cartridge includes shell. A carbon powder chamber is arranged in the shell. Furthermore, a photosensitive drum （68）, a charging roller （71） supplying power to the photosensitive drum （68）, a development roller （56） supplying carbon powder to the photosensitive drum （68）, a powder supply roller （51）supplying carbon powder to the development roller （56）and a powder discharge cutter （61）adjusting the thickness of the carbon powder layer on the development roller （56） are disposed in the shell. An end of the charging roller （71）is connected with a conducting strip. A voltage reduction device （81） is connected between the conducting strip and the powder supply roller （51） .

Description

Processing box

Technical field

The present invention relates to a printing consumable, and more particularly to a process cartridge for a laser printer. The present invention is based on a Chinese patent application filed on Apr. 20, 2010, the entire disclosure of which is hereby incorporated by reference.

Background technique

Laser printers are common printing devices that provide great convenience for modern office use. Most of the existing laser printers use a process cartridge that is detachably mounted in a laser printer to provide toner for printing. During the printing process, the toner loaded in the process cartridge is transferred onto the paper as a printing medium to form a desired paper. Patterns and text.

An existing type of process cartridge has a toner hopper containing toner and a waste toner hopper containing waste toner, and the structure of the process cartridge is as shown in FIG.

Referring to Figure 1, the process cartridge has a housing 1 with a handle 15 for easy grasp by the user.

Referring to Fig. 2, the casing 1 of the process cartridge is composed of a drum frame 11, a toner hopper frame 12, and two

end covers

13, 14, wherein the handle 15 is located on the drum frame 11. The toner hopper frame 12 has a toner hopper for accommodating toner, and a powder feed roller 21, a developing roller 25, and a powder discharging blade 31 are provided outside the toner hopper.

The drum frame 11 has a waste toner box for accommodating waste toner, and a photosensitive drum 36, a charging roller 41, and a cleaning blade 48 are disposed outside the waste toner box. When the process cartridge is assembled, the drum frame 11 and the toner hopper frame 12 are fixedly connected by the

end caps

13, 14 on both sides, and the drum frame 11, the toner hopper frame 12, and the

end caps

13, 14 are enclosed in a cavity for powder feeding. Parts such as the roller 21, the developing roller 25, the powder discharging blade 31, the photosensitive drum 36, the charging roller 41, and the cleaning blade 48 are located in the cavity.

Referring to Fig. 3, the powder feeding roller 21 has a mandrel 22 made of metal. The mandrel 22 is surrounded by an elastic layer 23, and both ends of the mandrel 22 extend outside the elastic layer 23, and the powder feeding roller 21 is used for development. The roller 25 supplies toner and cleans the residual toner on the surface after development of the developing roller 25. A conductive piece 24 is attached to one end of the mandrel 22, and the conductive piece 24 extends outside the end cover 14. After the process cartridge is mounted to the laser printer, the conductive sheet 24 is in contact with the electrical contacts of the laser printer, and the laser printer supplies a constant voltage to the conductive sheet 24 through the electrical contacts for eliminating some of the polar charge in the toner and providing sufficient The electric field force of the developing bias.

Similarly, the developing roller 25 also has a mandrel 26 made of metal. The mandrel 26 is covered with an elastic layer 27, such as a sponge, rubber, etc., and one end of the mandrel 26 is also connected with a conductive sheet 28, which is outside the conductive sheet 28. The end extends beyond the end cap 14. The conductive sheet 28 is connected to another electrical contact of the laser printer to receive the supplied voltage from the laser printer. When the process cartridge is in operation, the developing roller 25 adsorbs the carbon powder on the outer surface of the developing roller 25 by electrostatic action.

The powder discharging blade 31 is disposed in parallel with the developing roller 25, and has a holder 32 and a blade 33 mounted on the holder 32, and the blade 33 is elastically elastically pressed against the outer surface of the developing roller 25 for controlling carbon The thickness of the powder layer is evenly distributed on the surface of the developing roller, and a certain pressing force is also supplied to the developing roller 25 to rub the carbon powder to electrify it. One end of the holder 32 is connected to the conductive sheet 34, and one end of the conductive sheet 34 extends outside the end cover 14. After the process cartridge is loaded into the laser printer, the conductive sheet 34 is used to receive the voltage supplied by the laser printer.

The axis of the photosensitive drum 36 is disposed in parallel with the axis of the developing roller 25, the outer surface of the photosensitive drum 36 is a photosensitive layer, and the toner on the outer surface of the developing roller 25 can be transferred to the outer surface of the photosensitive drum 36.

As seen from the operation of the photosensitive drum 36, a charging roller 41 is provided upstream thereof, and the charging roller 41 has a metal core 42 which is provided with a conductive layer 43 outside, and the conductive layer 43 is in contact with the outer surface of the photosensitive drum 36. And power is supplied to the photosensitive drum 36. One end of the mandrel 42 is provided with a bracket 44 on which a spring 45 is attached, and the spring 45 is connected to the conductive piece 46. After the process cartridge is loaded into the laser printer, the conductive sheet 46 is used to receive the voltage supplied from the laser printer, and a high-voltage direct current is formed on the charging roller 41 to charge the photosensitive drum 36 to negatively charge the outer surface of the photosensitive drum 36.

A cleaning blade 48 is provided downstream of the photosensitive drum 36 for scraping off the toner remaining on the outer surface of the photosensitive drum 36 after the transfer is completed.

Referring to Fig. 4, the toner on the outer surface of the developing roller 25 is transferred to the outer surface of the photosensitive drum 36 by an electric field force. When the laser printer is in operation, the toner accommodated in the toner hopper is supplied to the outer surface of the developing roller 25 by the powder feeding roller 21, and the powder feeding roller 21 is continuously rotated during operation, and its rotation direction is as indicated by an arrow A1 in Fig. 4.

The powder feeding roller 21 is adjacent to the outer surface of the developing roller 25, so that the toner adsorbed on the outer surface is transferred to the outer surface of the developing roller 25 during the rotation of the powder feeding roller 21, and the developing roller 25 is also continuously rotated during operation, and its rotation direction As shown by the arrow A2 in FIG. During the rotation of the developing roller 25, the excess carbon powder on the outer surface thereof is scraped off by the powder discharging blade 31, and the blade 33 scrapes off the excessively thick carbon powder adsorbed on the outer surface of the developing roller 25, thereby ensuring the toner on the outer surface of the developing roller 25. The thickness of the layer is such that the thickness of the carbon powder layer on the outer surface of the developing roller 25 is uniform.

Since some toners may not be properly charged, or some of the toners have a negative charge, the powder knife 31 also needs to be negatively charged. When scraping excess toner, the negative charge on the blade needs to be transferred to the toner. Above, it is ensured that the toner on the outer surface of the developing roller 25 has a uniform negative charge.

On the other hand, the charging roller 41 charges the photosensitive drum 36 to uniformly charge the outer surface of the photosensitive drum 36. When the laser printer is in operation, the laser irradiates the surface of the photosensitive drum 36 with laser light with image information. This process is an exposure process, and a latent image is formed in a region where the surface of the photosensitive drum 36 is irradiated, that is, the charge in the exposed region disappears and is electrically neutral.

Since the unexposed area on the photosensitive drum 36 is negatively charged, and the exposed area is electrically neutral, and the toner on the outer surface of the developing roller 25 is also negatively charged, the carbon on the outer surface of the developing roller 25 is based on the principle of the force of movement of the electric charge in the electric field. The powder is moved by the electric field force from the outer surface of the developing roller 25 to the exposed area on the photosensitive drum 36. Also, since the electric field force of the non-exposed area is higher than the developing bias, the toner of the outer surface of the developing roller 25 does not move to the non-exposed area of the outer surface of the photosensitive drum 36, and this process is a developing process.

Finally, the paper as the printing medium passes under the photosensitive drum 36, the toner is transferred onto the paper, and the toner is heated and fixed on the paper, and the printing work is completed.

After the photosensitive drum 36 completes the transfer process, the cleaning blade 48 scrapes off the toner remaining on the outer surface of the photosensitive drum 36, and the waste toner is collected into the waste toner box to avoid affecting the next printing duty cycle of the photosensitive drum.

technical problem

Since the ability of different toners to obtain electric charges is not the same, and the powder feeding rollers of different materials have different adsorption capacities and transfer charge capacities for different carbon powders, the voltage required to be loaded on the powder feeding roller needs to be based on different toners and powder feeding. The characteristics of the roll material are adjusted.

However, the voltage value applied by the laser printer to the powder feed roller is fixed, which often causes the voltage applied to the powder feed roller to be too low, resulting in insufficient electric field force of the toner in the electric field, or the neutralization of the positively charged polar toner. . If the electric field force of the electric field of the toner is insufficient, the toner cannot be transferred to the surface of the photosensitive drum 36, resulting in insufficient blackness of printed characters or patterns. If the positively charged polar toner is not eliminated or neutralized, the positive carbon powder will be adsorbed on the unexposed area of the photosensitive drum 36, causing the area where the characters or patterns are not formed to form a gray dot, which affects printing. quality.

Technical solution

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a process cartridge that can effectively avoid print quality problems.

Another object of the present invention is to provide a process cartridge that ensures the blackness of printed characters or patterns.

In order to achieve the above main object, the present invention provides a process cartridge having a casing having a toner cartridge for containing toner, and a photosensitive drum, a charging roller for supplying power to the photosensitive drum, and transferring toner to the photosensitive film. a developing roller of the drum, a powder feeding roller for transferring the toner to the developing roller, and a powder discharging knife for adjusting the thickness of the carbon powder layer on the developing roller, one end of the charging roller is connected with the conductive member, wherein the conductive member and the end of the powder feeding roller There is a step-down device connected between them.

A preferred solution is that the buck device is a resistive or buck circuit.

In a further solution, the conductive member comprises a spring and a conductive strip connected to each other, and one end of the step-down device is connected to the conductive sheet.

Beneficial effect

The processing box manufacturer adjusts the pressure drop value of the pressure reducing device according to the characteristics of the process cartridge toner and the powder feeding roller, and ensures that the carbon powder adsorbed on the developing roller can be under a sufficient electric field force, and the powder feeding roller can neutralize The positive charge of the polar toner ensures that the toner can jump to the outer surface of the drum, and the text and pattern formed on the paper have sufficient blackness to avoid print quality problems.

DRAWINGS

Figure 1 is a structural view of a conventional process cartridge;

Figure 2 is a structural exploded view of a conventional process cartridge;

Figure 3 is a partially exploded enlarged view of a conventional process cartridge;

4 is a schematic enlarged view showing the structure of a powder feeding roller, a developing roller, a powder discharging knife, a charging roller, a photosensitive drum, and a cleaning blade of the conventional process cartridge;

Figure 5 is a partial structural view of the embodiment of the present invention after removing the housing;

Fig. 6 is a partial structural view showing a powder feeding roller, a charging roller and a resistor in the embodiment of the present invention.

The invention will now be further described in conjunction with the various embodiments and the accompanying drawings.

BEST MODE FOR CARRYING OUT THE INVENTION

The process cartridge according to the present invention has a casing composed of a drum frame, a toner hopper frame, and two end caps, and the toner hopper frame has a toner hopper containing toner, which is the same as the existing process cartridge.

In the casing, the process cartridge is provided with a powder feeding roller, a developing roller, a powder discharging knife, a charging roller, a photosensitive drum, and a cleaning blade, and the structure of the above components is as shown in FIG.

The powder feed roller 51 has a mandrel 52 made of metal, and the mandrel 52 is covered with an elastic layer 53. Similarly, the developing roller 56 also has a mandrel 57 which is wrapped with an elastic layer 58 and one end of which is connected to the conductive sheet 59 to receive the voltage supplied by the laser printer. The powder feed roller 51 and the developing roller 56 can supply the developing bias required for development, and the toner adsorbed on the surface of the developing roller 56 can be efficiently transferred to the surface of the photosensitive drum 68.

The powder discharging knife 61 is located above the developing roller 56 for controlling the thickness of the toner layer adsorbed on the developing roller 56. The powder discharging knife 61 has a blade holder 62 made of metal, and a blade 63 is mounted under the blade holder 62. The blade end of the blade 63 is in contact with the outer surface of the developing roller 56, and the excess toner adsorbed on the surface of the developing roller 56 can be scraped off. In order to control the thickness of the toner layer on the surface of the developing roller 56.

One side of the developing roller 56 is provided with a photosensitive drum 68 whose axis is disposed in parallel with the axis of the developing roller 56.

A charging roller 71 is provided above the photosensitive drum 68, and an axis of the charging roller 71 is disposed in parallel with the axis of the photosensitive drum 68. The outer surface of the charging roller 71 is in contact with the outer surface of the photosensitive drum 68 and is loaded with high voltage power to the outer surface of the photosensitive drum 68. A cleaning blade 78 is positioned above the photosensitive drum 68 for scraping off the toner remaining on the outer surface of the photosensitive drum 68 after the transfer.

Referring to Fig. 6, the charging roller 71 has a mandrel 72 made of metal, and the mandrel 72 is covered with an elastic layer 73, and the outer surface of the elastic layer 73 is coated with a conductive material. One end of the mandrel 72 is sleeved with a bracket 74. The bracket 74 is provided with a conductive member. The conductive member includes a spring 75 mounted on the bracket 74 and a conductive piece 76 connected to the spring 75. The conductive piece 76 extends to the end cover of the process box. In addition, the supplied voltage of the laser printer is received, and a negative charge is formed on the elastic layer 73.

A resistor 81 as a step-down device is connected between the conductive sheet 76 and the end of the powder feeding roller 51. One end 82 of the resistor 81 is soldered to the conductive sheet 76, and the other end 83 is soldered to the conductive sheet 54, and the conductive sheet 54 is sent. The one end of the powder roller 51 mandrel 52 abuts, thereby transferring the alternating current output from the laser printer to the powder feed roller 51. Since the voltage value of the laser printer to the charging roller 71 is much higher than the voltage value to be loaded by the powder feeding roller 51, the voltage applied to the conductive sheet 76 by the laser printer can be stepped down by the resistor 81 to ensure the voltage required by the powder feeding roller 51. Claim.

It can be seen that the appropriate voltage value applied to the powder feeding roller 51 can be calculated according to the characteristics of the toner and the material of the elastic layer 53 of the powder feeding roller 51, and the resistance 81 can be calculated according to the voltage value of the laser printer loaded on the conductive sheet 76. The resistance is selected and a suitable resistor 81 is selected to be soldered between the conductive sheet 54 and the conductive sheet 76.

When the laser printer is operated, since the powder feed roller 51 has a suitable negative voltage, it can neutralize the positively charged polar toner, and prevent the positively charged polar toner from being adsorbed on the unexposed area of the photosensitive drum 68. . Moreover, a suitable negative voltage is formed on the powder feeding roller 51, which is advantageous for forming a suitable electric field force in the vicinity of the powder feeding roller 51 and the developing roller 56, ensuring that the toner jumps to the surface of the photosensitive drum 68, and ensures the characters formed on the paper. The blackness of the pattern is sufficient to avoid print quality.

Of course, the above solution is only one embodiment of the present invention, and in practice, there may be more conversions, for example, using a dedicated step-down circuit instead of a resistor as a step-down device, preferably, an adjustable resistance drop is selected. The pressure circuit is more convenient for the production of the process cartridge; or one end of the resistor is connected to the spring instead of the conductive sheet of the charging roller, etc., and these changes do not affect the implementation of the present invention.

Finally, it should be emphasized that the present invention is not limited to the above embodiments, and minor changes such as changes in the step-down device and changes in the connection position of the step-down device should also be included in the scope of protection of the claims of the present invention.

Industrial applicability

Compared with the prior art, in the process cartridge provided by the present invention, one end of the powder feeding roller is not provided with a conductive sheet, that is, the powder feeding roller does not take power from the laser printer. Moreover, a step-down device is disposed between the conductive member of the charging roller and the end of the powder feeding roller, and when the laser printer applies a voltage to the charging roller, the voltage is loaded on the powder feeding roller through the pressure reducing device, thereby applying a voltage to the powder feeding roller. . In this way, the manufacturer of the process cartridge can calculate the appropriate voltage value to be fed to the powder feed roller according to the characteristics of the toner loaded in the process cartridge and the characteristics of the material of the powder feed roller installed, thereby calculating the appropriate pressure drop device according to the voltage value of the charge roller. The step-down value is used to select a suitable step-down device. Since the voltage value of the laser printer to the charging roller is much higher than the voltage value to be loaded by the powder feeding roller, the process cartridge provided by the present invention can ensure that the powder feeding roller obtains a sufficiently high voltage from the charging roller conductive member.

Claims

Processing box, including

a casing having a toner hopper containing toner, and a casing, a charging roller for supplying power to the photosensitive drum, and a developing roller for transferring toner to the photosensitive drum, a powder feeding roller for transferring toner by the developing roller, and a powder discharging knife for adjusting a thickness of the carbon powder layer on the developing roller, wherein one end of the charging roller is connected to the conductive member;

It is characterized by:

A step-down device is connected between the conductive member and the shaft end of the powder feeding roller.
A process cartridge according to claim 1, wherein:

The buck device is a resistor.
A process cartridge according to claim 1, wherein:

The buck device is a buck circuit.
A process cartridge according to claim 3, wherein:

The step-down circuit is a step-down circuit with adjustable resistance.
A process cartridge according to any one of claims 1 to 4, characterized in that:

The conductive member includes a spring and a conductive sheet connected to each other, and one end of the step-down device is connected to the conductive sheet.
A process cartridge according to any one of claims 1 to 4, characterized in that:

The conductive member includes a spring and a conductive piece connected to each other, and one end of the step-down device is connected to the spring.
A process cartridge according to any one of claims 1 to 4, characterized in that:

The powder feed roller includes a mandrel and an elastic layer wrapped around the mandrel, and one end of the pressure reducing device is coupled to an end of the mandrel.