JPH0741174B2 - Method of controlling particle size in dry powder manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an apparatus for producing a dry powder such as a toner used in a copying machine, in which the dry powder is branched directly from the production line to be on-line. The present invention relates to a method and a device for installing a particle size measuring device capable of continuously measuring a particle size and automatically controlling a manufacturing device according to a result measured by the measuring device.

(Prior Art) In a copying machine, a toner made of dry powder is used as a developer, but the toner is manufactured after strict particle size control.

In such a toner manufacturing apparatus, conventionally, an operator manually samples the toner manufactured by the manufacturing apparatus from the manufacturing line and carries it to a measuring apparatus for measurement. (Hereinafter, this will be referred to as an off-line measurement method.) In the above-mentioned off-line measurement method, when the distance between the manufacturing apparatus and the measurement apparatus is long, it takes time to carry the sample, and the measurement result is immediately obtained after sampling. There was a problem that was not found. Therefore, when the powder particle size in the production line is to be controlled based on the measurement result of the particle size, a time delay becomes large, which makes it impossible to control the particle size in a desirable manner. Was causing a big problem above.

To improve the drawbacks of the above offline measurement method,
A measuring device is also known in which the powder is branched and delivered directly from the production line to the measuring device, and the particle size of the powder is always continuously measured. (Hereinafter, this is referred to as an off-line measurement method) In the conventionally known off-line measurement method, the powder is diverged from the manufacturing line and taken out, and the powder is fluid-transported in the pipe together with the compressed air. Was transported to the measuring device.

On the other hand, when the powder is transported along with air by a pipe, the powder adheres to the inner surface of the pipe, or the powder accumulates in the bent part of the pipe, and this accumulated part is peeled off at the time of later measurement. As a result, the measurement results are unreliable. (This is called the contamination phenomenon.) Such a contamination phenomenon is caused when powder is alternately delivered from a plurality of manufacturing equipment lines to one measuring device, or even when one manufacturing equipment is used. In the case of taking out powder from a place following the steps of step 1 and delivering it to the measuring device, etc., it becomes a system that branches out the powder from many places and measures the powder with one measuring device. If so, there was a particular problem.

In order to improve the above-mentioned drawbacks, the inventors of the present invention sampled a dry powder from a line of a manufacturing apparatus, mixed the dry powder into a liquid, and measured the particle size of the powder by a pipe line of the mixed liquid. We have already proposed an on-line dry powder particle size measuring method and apparatus that fluid-transports to the apparatus to eliminate the above-mentioned contamination phenomenon and always obtain highly reliable measurement data. (Japanese Patent Application No. 1-108174) In the known or proposed dry powder particle size measuring method and device, the operator judges the measurement result of the particle size obtained by the measuring device and manufactures it by hand. Controlled each part of the device.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional toner manufacturing apparatus control system, in order to continuously produce a stable particle size, an operator must always perform measurement and control operations with a constant operation. In addition, the skill of the operator is required.

Therefore, an object of the present invention is to produce a toner having a stable particle diameter continuously without an operator after the operation is started once in the above-mentioned known or proposed offline method and apparatus for measuring a particle diameter of dry powder. It is another object of the present invention to provide a control method and a control device for a toner manufacturing apparatus which are enabled.

(Means for Solving the Problem) A feature of the present invention is that a computer to which the data measured by the particle size measuring device is input, and an arithmetic processing by the computer to instruct operating conditions of each device. When a remote command device is provided and the remote command device controls the rotation of the motor of the feeder, the crushing pressure is adjusted by the crushing pressure adjuster, and the opening / closing adjustment of the first damper and / or the second damper is performed, When the difference between the measured particle diameter of the powder and the set particle diameter is large to small, the range is divided into a plurality of ranges, and when the difference is large, the motor, the crushing pressure regulator, the first and / or the second damper If the error is small, only the opening and closing adjustment of the first and / or second damper is performed. The rotation speed of the motor, the crushing pressure with the crushing pressure adjuster, and the opening and closing of the damper are adjusted in this order.

(Example) Hereinafter, an example of the control method and apparatus of the present invention will be described with reference to FIG.

The roughly crushed raw material 1 is supplied to a feeder 3 via a chute 2. The feeder 3 is rotationally driven by the motor M ₁ ,
The raw material 1 supplied to the feeder 3 is introduced from the feeder 3 into the coarse powder cutting classifier 4 by pneumatic transportation. The motor
The supply amount of raw material 1 is changed by adjusting the rotation speed of M ₁ . The coarse-powder cut classifier 4 is composed of a cyclone type classifier, and a crusher 5 is provided below the coarse-powder cut classifier 4. Then, an outlet 5A of the crusher 5 and an inlet 4A of the coarse powder cutting classifier 4 are connected by a circulation path 6,
The coarse powder is crushed while circulating the powder between the coarse powder cut classifier 4 and the pulverizer 5. In this case, the crushing pressure of the crusher 5 is adjusted by the pressure adjuster R to change the particle size for crushing. The coarse-powder cutting classifier 4 drops coarse powder in the circulating powder to the pulverizer 5 again, and at the same time takes out the powder having a predetermined particle size range from the outlet 4B, and is an ultrafine powder. Is classified and removed via the damper A. Then, the ultrafine powder that has been classified and removed through the damper A is pneumatically conveyed to the back filter 8 through the conduit 7. The powder having a predetermined particle size range from which the ultrafine powder and the coarse powder have been removed is again applied to the classifier 9 for cutting the ultrafine powder, and the residual ultrafine powder is further cut by this. The powder obtained by cutting the residual ultrafine powder is pneumatically transported to the fine powder cutting classifier 11 via the feeder 10. The fine-powder cutting classifier 11 cuts powder having a particle size of a predetermined particle size or less, and at the same time removes extra fine powder through the damper B. The powder is a product powder P having a particle size within a predetermined range. The ultrafine powder classified and removed by the damper B is conveyed to the back filter 8 via the pipe 7. The fine powder classified and removed by the fine-powder cut classifier 11 is further applied to the classifier 12 to cut the ultrafine powder, and then stored in the storage container 13.

The particle size measuring system samples only a part of the product powder P obtained by cutting the ultrafine powder and the fine powder by the fine powder cutting classifier 11 and mixes and disperses the sampled powder in the liquid to the measuring device. The fluid is transported by a pipeline.

That is, a part of the product powder P is sampled by the sampling device 14 and fed to the mixer 15. The mixer 15 has a liquid injection pipe 17 communicating with a liquid source 16 such as water and a dispersant injection pipe 19 communicating with a dispersant supply tank 18 in which a dispersant such as a surfactant is stored. A liquid and a dispersant are injected into the sampled powder to mix and disperse them. The mixer 15 is provided with a pump 20 for circulating the mixed liquid.

The sampling, mixing and fluid transportation device is also installed in the classifier 9 installed in the middle of the manufacturing line. Therefore, sampling, mixing, installed in the classifier 11 below,
The feeding device is referred to as a secondary sampling system, and the sampling, mixing, and feeding device installed in the classifier 9 is referred to as a primary sampling system. Since the primary sampling system is the same as the secondary sampling system installed in the fine powder cutting classifier 11, the same reference numerals are given and the description thereof is omitted.

The liquid source 16 and the dispersant supply tank 18 are used in both sampling systems, and therefore, the liquid injection pipe is used.
A pipe 21 that connects the liquid source 16 and the pipe 17 and a pipe 22 that connects the dispersant injection pipe 19 and the dispersant supply tank 18 are provided with three-way valves 23 and 24, respectively. The structure is such that 24 is switched to supply the liquid and the dispersant to the respective mixing trays 15, 15.

In addition, the particle size measuring device 25 is also used for both sampling systems, and a three-way valve 28 is provided in the middle of the two pipes 26, 27 from the mixers 15, 15 and by switching and using it. Only one sampling device 14 can be selected. One pipe 26 is connected to the liquid source 16 via a three-way valve 29, a pipe 30, and a three-way valve 31, and the other pipe 27 is also similarly connected via a three-way valve 29, a pipe 30, and a three-way valve 31. Contacting liquid source 16. The three-way valve 29 connects on the one hand to a pipe 30 and on the other hand to a pipe 33 which opens inside the mixer 15.
Further, the circulation path of the mixed liquid of the mixer 15 is the mixer 15, the pump 20,
It is formed by a three-way valve 31, a pipe 30, a three-way valve 29, and a pipe 33.

When measuring the sampled mixed liquid, the mixed liquid accumulated in the pipe 30 is used as the liquid source 16, the liquid injection pipe 17, and the three-way valve.
The liquid is transported to the particle size measuring device 25 by the liquid pressure of the liquid source 16 through the route of 31, pipe 30, three-way valve 29, and pipe 26.

Next, a manufacturing line control method and apparatus will be described.

Among the devices on the production line, the devices that influence the particle size of the product toner are mainly the following devices.

Rotational speed of change of the rotational speed the motor M ₁ of the motor M ₁ of the feeder 3 will shall change the amount of raw material supplied to the feeder 3, the particle size becomes large and the supply amount is large, less supply amount Then, the particle size becomes smaller. If the supply amount by the supply device 3 is excessively reduced, the production amount itself is reduced. Therefore, it is desirable to avoid reducing the supply amount as much as possible.

Crushing pressure of the crusher 5 In the crusher 5, the powder is placed on compressed air to collide with the collision plate, so the crushing pressure (linked to the amount of compressed air)
Is larger, the particle size is smaller, and if the crushing pressure is smaller, the particle size is larger.

In the A and B damper opening classifier, if the opening of the damper is increased, the pulling on the damper side becomes stronger and the amount of powder falling downward increases. Therefore, the A damper drops into a crusher and is pulverized again to have a smaller particle size, and the B damper also collects fine powder and the particle size of the powder becomes smaller.

In the present invention, the particle size of the powder is adjusted by adjusting the supply amount by the supply device 3, the crushing pressure of the crusher 5, and the opening amounts of the A and B dampers, and has the following configuration. There is.

The data measured by the particle size measuring device 25 is stored in the computer.
Enter 40. The computer 40 arithmetically processes the input data as described later, and inputs a signal to the remote command device 42 via the D / A converter 41. Motor M ₁ of the remote commander 42 feeder 3, the motor M ₂ of feeder 10 (which is not necessary), given grinding pressure regulator R, dampers A, a signal to the damper B, and the motor M ₁ , M ₂ is adjusted to a predetermined value, the crushing pressure is adjusted by the crushing pressure adjuster R, and the openings of the dampers A and B are changed. The remote command device 42 performs other remote operations (for example, operation of the water supply source 16 and operation of the mixer 15), but since the purpose of the present invention is to control the particle size, description thereof will be omitted.

The particle size control of the present invention is as follows.

[1] When the particle size is controlled by the measurement data of both the primary sampling system and the secondary sampling system (product) (in the following, the numerical value of the difference from the set value of the particle size is μ) (A) Motor Adjustment of M ₁ , crushing pressure and A damper (1) If the current particle size is larger than the set value, control as follows by the computer.

* When the difference from the set value is 1.5 or more Reduce the rotation of motor M1 by ₂ rpm.

Increase the crushing pressure by 0.2 Kg / cm ² .

Open the A damper 2 °.

* When the difference from the set value is 1 or more and less than 1.5 Increase the grinding pressure by 0.2 Kg / cm ² .

Open the A damper 2 °.

* When the difference from the set value is 0.5 or more and less than 1 Open the A damper 2 °.

* When the difference from the set value is 0.2 or more and less than 0.5 Open the A damper by 1 degree.

* If the difference from the set value is less than 0.2 No change in condition (2) If the current particle size is smaller than the set value, control as follows by the computer.

* When the difference from the set value is 1.5 or more Increase the rotation of the motor M1 by ₂ rpm.

Reduce the crushing pressure by 0.2 Kg / cm ² .

Close A damper 2 °.

* When the difference from the set value is 1 or more and less than 1.5 Reduce the crushing pressure by 0.2 Kg / cm ² .

Close A damper 2 °.

* When the difference from the set value is 0.5 or more and less than 1 Close A damper 2 °.

* When the difference from the set value is 0.2 or more and less than 0.5 Close A damper 1 °.

* When the difference from the set value is less than 0.2. No condition change. (B) Adjustment of B damper (1) If the current particle size is larger than the set value, control by computer as follows.

* When the difference from the set value is 0.2 or more Open the B damper 2 °.

* If the difference from the set value is less than 0.2 No change in condition (2) If the current particle size is smaller than the set value, control as follows by the computer.

* When the difference from the set value is 0.2 or more Close the B damper 2 °.

* If the difference from the set value is less than 0.2 No condition change [2] When the particle size is controlled only by the measurement data of the secondary sampling system (product side) (A) Adjustment of Moses M ₁ , crushing pressure, A damper (1) When the current particle size is larger than the set value, the computer controls as follows.

* When the difference from the set value is 1.5 or more Reduce the rotation of motor M1 by ₂ rpm.

Increase the crushing pressure by 0.2 Kg / cm ² .

Open the A damper 2 °.

Open the B damper 2 °.

* When the difference from the set value is 1 or more and less than 1.5 Increase the grinding pressure by 0.2 Kg / cm ² .

Open the A damper 2 °.

Open the B damper 2 °.

* When the difference from the set value is 0.5 or more and less than 1 Open the A damper 2 °.

Open the B damper 2 °.

* If the difference from the set value is 0.2 or more and less than 0.5 Open the B damper 2 °.

* When the difference from the set value is 0.2 or less No change in conditions (2) If the current particle size is smaller than the set value, control as follows by the computer.

* When the difference from the set value is 1.5 or more Increase the rotation of the motor M1 by ₂ rpm.

Reduce the crushing pressure by 0.2 Kg / cm ² .

Close A damper 2 °.

Close the B damper 2 °.

* When the difference from the set value is 1 or more and less than 1.5 Reduce the crushing pressure by 0.2 Kg / cm ² .

Close A damper 2 °.

Close the B damper 2 °.

* When the difference from the set value is 0.5 or more and less than 1 Close A damper 2 °.

Close the B damper 2 °.

* When the difference from the set value is 0.2 or more and less than 0.5 Close the B damper 2 °.

* Set value and the difference is more None If conditions change 0.2 following is an example of a control condition of the present invention, each of the numerical values employed in the present invention (e.g., rotation up of the motor M ₁ per once down The crushing pressure can be increased or decreased, the damper opening / closing angle, etc.) can be appropriately changed.

The order of influence on the particle size adjustment of the powder is the supply amount by the supply device 3 (the number of rotations of the motor M ₁ ), the crushing pressure, and the opening / closing of the damper. In some cases, the adjustment cannot be made only by adjusting the crushing pressure or the A and B dampers. Therefore, in order to deal with such an unadjustable case, the crushing pressure,
It is necessary to set adjustment limits for the A and B dampers, and to adjust the powder supply amount and the crushing pressure by the feeder 3 when such adjustment limits are reached.
Therefore, if the adjustment limits of the A and B dampers are exceeded, the crushing pressure (in addition to this, the supply amount of the feeder 3 may be adjusted) is adjusted, and if the adjustment limits of the A and B dampers and the crushing pressure are exceeded. It is necessary to add an adjustment condition for adjusting the supply amount of the feeder 3 to the adjustment condition,
Such condition addition is not necessary for the present invention because it is added as necessary.

Although the above description has been described with respect to the toner production line used in the copying machine, the present invention is also applicable as a sampling device in other dry powder production lines, and these are also included in the present invention. It is what is done.

Further, in the above-mentioned embodiment, the one in which the dry powder sampled is fluidly transferred to the measuring device is described, but the present invention is not limited to the means for transferring the dry powder to the measuring device. It also includes various other automatic transfer methods.

(Effects of the Invention) According to the control method of the present invention described above, the following effects are achieved.

Fig. 2 shows the actual product when the particle size of the product is set to 14.6μ.
It is a diagram of the transition of particle size of 50% diameter in 48 hours. As can be seen from the diagram, compared with the case where the control shown by the chain line is not performed, the one controlled only by the measurement data of the secondary sampling system shown by the dotted line The change is smaller, and the one controlled by both the measurement data of the primary sampling system and the secondary sampling system shown by the solid line is even smaller.

Fig. 3 is a diagram showing changes in product yield in 48 hours. As can be seen from the figure, when the control indicated by the chain line is not performed, the yield decreases with the passage of time, whereas the control performed only by the measurement data of the secondary sampling system indicated by the dotted line shows the change in time. The yield increases with the passage of time, and those controlled by both the measurement data of the primary sampling system and the secondary sampling system shown by the solid line have a stable high yield regardless of the passage of time.

Further, according to the method of the present invention, since the control of the particle size is managed by the computer, it is not necessary for the person performing the work or operation to be skilled, and the operator always has a stable particle size regardless of the operator's regret. And the product yield can be obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a control system of a dry powder manufacturing apparatus to which the present invention is applied, and FIG. 2 is a diagram showing a transition of a product particle size for 48 hours when a set value is 14.6 μ, 50% on the vertical axis
The particle diameter is the diameter, and the horizontal axis is the time. FIG. 3 shows the transition of the yield of products for 48 hours, in which the vertical axis represents the yield (%) and the horizontal axis represents the time. 3: Feeder, 5: Crusher, M ₁ : Motor R: Pressure regulator, A: Damper, B: Damper

Front page continuation (72) Inventor Toshiaki Miyashita 3-1, Somoe-cho, Shizuoka-shi, Shizuoka Prefecture Inside the Tomagawa Paper Mill Chemicals Mill (72) Hideo Ishida, 3-1, Somae-cho, Shizuoka-shi, Shizuoka Prefecture No. Tomoegawa Paper Co., Ltd., within a chemical product mill (56) Reference Japanese Patent Laid-Open No. 58-153547 (JP, A) Jitsuko Sho 49-24372 (JP, Y1)

Claims (3)

[Claims] 1. A feeder that feeds raw materials by driving a motor, a coarse-powder cut classifier that receives a powder from the feeder to perform classification, and a powder that is dropped and fed from the coarse-powder cut classifier. A crusher, a crushing pressure adjuster that adjusts the crushing pressure by the crusher, a first damper that communicates with the classifier to classify ultrafine powder, and the powder from the crusher is supplied. First classifier, a second classifier supplied with powder from the first classifier to classify the product powder, and a second classifier to communicate with and extract ultrafine powder A second damper, a first sampling device provided in the first classifier to automatically sample powder, and a second damper provided in the second classifier to automatically sample product powder A second sampling device, the first sampling device and the second sampling device; In an automatic measuring method in a dry powder manufacturing apparatus, which comprises a particle size measuring apparatus for automatically feeding a powder sampled by a sampling apparatus and measuring the particle size, the particle size measuring apparatus measures the particle size. A computer to which the data is input and a remote command device that is operated by the computer to instruct the operating conditions of each device are provided, and the remote command device controls the rotation of the motor of the feeder and the grinding pressure regulator. When adjusting the crushing pressure and adjusting the opening and closing of the first damper and / or the second damper, the range from the case where the difference between the measured particle size of the powder and the set particle size is large to the case where it is small is made plural. Separately, when the error is large, the motor, the crushing pressure adjuster, and the first and / or second dampers are respectively adjusted, and when the error is small, Only the opening and closing adjustment of the first and / or second damper is performed, and in the middle thereof, the order of the control operation is adjusted in the order of the rotation speed of the motor, the adjustment of the crushing pressure by the crushing pressure adjuster, and the opening and closing of the damper. And a method for controlling the particle size in a dry powder manufacturing apparatus. 2. The method for controlling the particle size in the dry powder manufacturing apparatus according to claim 1, wherein the control is performed only by the measurement data of the particle size of the second classifier. 3. A method for controlling a particle size in a dry powder manufacturing apparatus according to claim 1, wherein the particle size is controlled by measuring the particle size measurement data of the first classifier and the second classifier.