JP3292871B2 - Collision type crusher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collision type pulverizer using a jet jet, and more particularly, to a developer, that is, a toner and / or a toner used in an electrophotographic image forming method.
Alternatively, the present invention relates to a material suitable for producing a colored resin powder for toner.

[0002]

2. Description of the Related Art As an electrophotographic image forming apparatus,
For example, copiers, printers, and the like have become widespread, and their multicoloring has begun to spread. However, a collision-type pulverizing apparatus has been used in the production of toner as a developer and / or colored resin powder for toner. (Japanese Utility Model Laid-Open No. 1-148740,
JP-A-5-303230, JP-A-6-52970
Reference).

FIG. 6 is a schematic overall configuration diagram of a conventional general collision type pulverizer, and this collision type pulverizer has a closed circuit. In the figure, reference numeral 30 denotes a nozzle for jetting compressed air, and a jet jet 32 passing through an acceleration tube 31.
Sucks the crushed object 34 from the crushed object supply hole 33 opened in the middle thereof, moves the crushed object 34 to the crushing chamber 35 together with the crushed object, and contacts the crushing surface 36a of the collision member 36 in the crushing chamber 35 The crushed object 34 is caused to collide. The crushed object 34 colliding with the collision surface 36a is crushed by the impact at that time. The crushed material 37 formed in the crushing chamber 35 is sent to a classifier 39 through a path 38. In addition, a new crushed object 34 a is supplied to the path 38 through a path 40. In the classifier 39, the refined pulverized material 37 is collected through the path 41,
The coarse pulverized material is sent to the hopper 42 and is again
5 is used for grinding.

[0004]

In the collision-type pulverizer described above, the object to be pulverized is supplied stably in the jet stream, and the object to be pulverized is conveyed by a solid / gas two-phase flow. It is important whether the powder is crushed by colliding with the collision surface 36a. Further, in the collision-type pulverizer, the in-machine stability of the classifier 39 that makes the whole a closed circuit affects the pulverization efficiency.

However, in the conventional apparatus, the supply amount of the crushed object 34 to the crushed object supply hole 33 is governed by the return amount of the classifier 39, and the supply hole depends on the characteristics of the powder. In some cases, excessive supply to 33, temporary breathing or shortage of supply occurred. Such a phenomenon has caused a problem that the amount of the crushed object 34 contained in the jet jet 32 in the acceleration tube 31 is not determined. Further, when the supply hole 33 causes a temporary breathing or insufficient supply of the crushed material 34, the gas inside the hopper 42 is sucked from the supply hole 33 by the ejector effect due to the pressure fluctuation inside the acceleration tube 31, and the upstream thereof. Thus, the internal pressure of the classifier 39 on the side was also affected, and the grinding efficiency was reduced. Therefore, an object of the present invention is to provide a collision-type pulverizer capable of improving the pulverization processing capability and the pulverization accuracy.

[0006]

According to the present invention, in order to achieve the above technical object, the object to be ground supplied from the hopper is basically transported to the collision chamber by a jet jet, and On the premise of a collision-type pulverizer that crushes the object to be crushed against the collision member, the apparatus has a constant-quantity supply unit that quantitatively supplies the object to be ground to the hopper.

According to a preferred aspect of the present invention, a first detecting means for detecting an amount of the object to be crushed present in the hopper, and a signal which is received in the hopper upon receiving a signal from the first detecting means. And control means for controlling the quantitative supply means so that the amount of the material to be ground is kept substantially constant.

According to another preferred aspect, the collision-type pulverizing device is constituted by a closed circuit, and in addition to the quantitative supply means, the hopper, and the collision chamber, the collision-type pulverization device is configured to pulverize the pulverized material pulverized in the collision chamber. A classifier for collecting the fine powder, a second detector for detecting a state inside the classifier, and a pulverized object present in the hopper receiving a signal from the second detector. And control means for controlling the quantitative supply means so that the amount of the liquid is kept substantially constant.

According to another preferred embodiment, the collision type crushing device is constituted by a closed circuit, and the crushed material crushed in the collision room is used in addition to the fixed amount supply means, the hopper and the collision room. Having a classifier for collecting fine powder, further, a first detection means for detecting the amount of the crushed material present in the hopper, a second detection means for detecting the internal state of the classifier, Control means for receiving the signals from the first detection means and the second detection means, and controlling the fixed-quantity supply means such that the amount of the material to be ground present in the hopper is kept substantially constant. Have.

[0010] According to another preferred embodiment, there is provided a scrubbing means provided in the hopper for preventing the crushed material from adhering to the inside of the hopper and / or blocking the outlet of the hopper. And an outlet changing means disposed to face the outlet of the hopper and changing an effective opening area of the outlet and a flow path thereof.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. For convenience of explanation, the object to be ground will be described first. The raw material of the material to be ground has the following composition.

Raw material composition Polyester resin 50 parts by weight Styrene acrylic resin 50 parts by weight Phthalocyanine pigment 7 parts by weight Low molecular weight polyethylene 2 parts by weight Negative charge control agent 2 parts by weight

The raw materials having the above-mentioned composition are mixed by a mixer, and the mixture is melt-kneaded at about 200 ° C. by an extruder, then cooled and solidified, and is then coarsely reduced to particles of 200 to 20,000 μm by a hammer mill. It was crushed to make a material to be crushed.

First Embodiment (FIG. 1) FIG. 1 is an overall configuration diagram of a collision-type pulverizer according to a first embodiment. In the figure, reference numeral 1 denotes a compressed air discharge nozzle, and the compressed air discharged from the nozzle 1 is supplied to an acceleration tube 2. A pulverized material supply hole 3 is provided in the middle of the accelerating tube 2, and the pulverized material 5 in the raw material hopper 4 is supplied by the jet jet of the accelerating tube 2.
Is the accelerating tube 2 through its supply hole 3, namely the hopper outlet.
Is sucked into. Object 5 to be crushed in accelerator tube 2
Flows toward the pulverizing chamber 7 together with the jet jet of the acceleration tube 2, that is, the high-speed air flow 6, and collides with the collision surface 8 a of the collision member 8 disposed at a position facing the outlet of the acceleration tube 2, and the impact causes Crushed.

The crushed material 9 crushed in the crushing chamber 7 is sent to a fixed type air classifier 11 through a path 10, and the fine powder fined to a predetermined particle size is collected through a path 12. The coarse powder is once stored in the container 13. The container 13 is supplied with a new material to be crushed 5a through a path 14. A fixed quantity feeder 15 is provided between the outlet of the container 13 and the raw material hopper 4.
Thereby, the material 5 to be ground in the container 13 is quantitatively sent to the raw material hopper 4. As the fixed-quantity feeder 15, an appropriate feed feeder such as an accumulate type applying a rotating plate type, an electromagnetic type applying a vibration type, or a spiral type applying a screw type can be adopted.

Using the pulverizing apparatus shown in FIG. 1, compressed air with a flow rate of 5 m ³ / min is introduced from the nozzle 1 and the material 5 to be pulverized is supplied from the quantitative feeder 15 to the raw material hopper 4 at a rate of 25 kg / hr. Crushed. The crushed material 9 obtained in the crushing chamber 7
Collected fine powder contained therein through a classifier 11. The collected fine powder was measured over time with a particle flow distribution measuring device (Coulter counter). The results are shown in Table 1 below.

[0017]

[Table 1] Time (min) 5 10 15 30 45 60 90 120 Volume average particle size (μm) 8.4 8.4 8.5 8.4 8.4 8.5 8.5 8.5 8.5

From Table 1, it can be seen from the table that the fixed amount of gas to be supplied into the supply hole 3 makes the amount of gas suction inside the hopper constant and the balance of the classifier stable. Is stable.

FIGS. 2 to 5 show another embodiment of the present invention. In these other embodiments, the same elements as those in the above-described first embodiment are denoted by the same reference numerals, and the description thereof will be appropriately omitted. The features of these embodiments will be described below.

Second Embodiment (FIG. 2) In this embodiment, a sensor 17 is provided in the raw material hopper 4, and when the height of the material 5 to be crushed existing in the hopper 4 becomes higher than a predetermined level, the sensor 17 is activated. A signal is sent to the quantitative feeder 15, and the operation of the quantitative feeder 15 is interrupted. Thus, the height level of the powder existing in the raw material hopper 4, that is, the object 5 to be crushed is always kept almost constant. In the above description, only one sensor is provided, but two sensors for detecting the upper limit position and the lower limit position of the powder surface may be provided. in this case,
When the sensor that detects the upper limit position of the powder surface detects the powder surface, a stop signal is issued to stop the fixed quantity feeder 15.
When the sensor that detects the lower limit position of the powder surface detects the powder surface, it issues an operation signal to operate the quantitative feeder 15, and the material 5 to be ground until the sensor that detects the vertical position detects the powder surface. Is supplied. As a result, since the powder surface always exists between the upper limit position and the lower limit position, the crushed object 5 is supplied to the crushed object supply port 3 with maximum stability.

As in the first embodiment, compressed air having a flow rate of 5 m ³ / min is introduced from the nozzle 1 using the pulverizing apparatus shown in FIG. 2, and the pulverized material 9 obtained in the pulverizing chamber 7 is classified into a classifier. Through 11, fine powder contained therein was recovered. The collected fine powder was measured over time with a particle flow distribution measuring device (Coulter counter). The results are shown in Table 2 below. In addition, the fixed-quantity feeder 15 that is ON / OFF controlled by a signal from the sensor 17 supplies the material 5 to the raw material hopper 4 at a rate of 26 kg / hr.

[0022]

[Table 2] Time (min) 5 10 15 30 45 60 90 120 Volume average particle size (μm) 8.1 8.1 8.2 8.1 8.0 8.1 8.2 8.2

From Table 2, it can be seen that the material 5
Is supplied at the maximum stability, so that the pulverizing ability is improved. Further, compared with the case of the apparatus shown in FIG. 1, the gas suction amount in the hopper is further reduced, so that the performance (accuracy) is improved by improving the classification balance, and the volume average particle diameter can be reduced.

Third Embodiment (FIG. 3) In this embodiment, as in the second embodiment, the raw material hopper 4
A sensor 17 is provided, and when the height level of the material 5 to be crushed present in the hopper 4 becomes higher than a predetermined level, a signal is sent from the sensor 17 to the quantitative feeder 15 and the operation of the quantitative feeder 15 is interrupted. Is done. Further, the classifier 11 is provided with a pressure sensor 19.
Is sent to the quantitative feeder 15 and the sensor 1
The accuracy of the control of the supply amount of the fixed-quantity supply device 15 is enhanced together with the signal from the control unit 7.

As in the first embodiment, compressed air having a flow rate of 5 m ³ / min is introduced from the nozzle 1 using the pulverizing apparatus shown in FIG. 3, and the pulverized material 9 obtained in the pulverizing chamber 7 is classified into a classifier. Through 11, fine powder contained therein was recovered. The collected fine powder was measured over time with a particle flow distribution measuring device (Coulter counter). The results are shown in Table 3 below. It is turned on by signals from the sensor 17 and the pressure sensor 19.
The quantitative feeder 15 controlled by the / OFF control supplies the material 5 to the raw material hopper 4 at a rate of 26.5 kg / hr. Also,
Among the particles contained in the collected fine powder, coarse particles (particle size
Table 3 also shows the content ratio (wt%) of 12 μm or more).

[0026]

[Table 3] Time (min) 5 10 15 30 45 60 90 120 Volume average particle size (μm) 8.1 8.1 8.2 8.1 8.0 8.1 8.2 8.2 Content ratio of coarse particles 0.9 0.8 0.9 1.0 0.9 0.9 0.8 0.9

From Table 3, it can be seen that both the supplied amount of the material to be ground and the volume average particle size of the ground material are very good. In addition, it can be seen that classification accuracy and performance are improved by pressure management in the classifier.

Fourth Embodiment (FIG. 4) This embodiment shows an example in which the raw material hopper 4 is provided with a wiping device 20. The removing device 20 may be an externally mounted type such as a knocker type or a vibrator type, or may be a device installed inside the hopper 4 such as a vibrator or an air bag. According to this embodiment, it is possible to prevent adhesion (bridge) and / or blockage of the material 5 to be crushed, which is likely to occur inside the hopper 4, due to eccentricity, aggregation and the like. This removal device 2
Needless to say, 0 can be applied to all of the above-described first to third embodiments. By the way, the operation was carried out under the same conditions as those of the first, second and third embodiments, and the vibrator-type sweeping-off device 20 was installed in the hopper 4 and 240 mi.
n. After the operation, the inside of the hopper 4 was observed, but no adhesion of the crushed object 5 and no blockage due to the crushed object 5 could be observed.

Fifth Embodiment (FIG. 5) In this embodiment, the raw material hopper 4 has a material supply hole 3, ie, an effective opening area of the hopper outlet and a substantial outlet changed in the portion of the supply hole 3. Outlet changing means 2
2 are provided. The outlet changing means 22 is formed of a member tapering toward, for example, the supply hole 3 disposed along the axis of the hopper 4, and this member is moved up and down by a driving means (not shown) to make the supply hole 3 effective. The opening area is changed. Also, the tapered outlet changing means 22
May be formed in a non-circular shape such as an ellipse, and a motor 23 connected to the shaft 22a of the outlet changing means 22 may be provided as shown in FIG. In this manner, by rotating the motor 23 by a predetermined angle, the shaft 22a rotates by the stepping method, the tapered member 22 descends, and the substantial flow path of the material supply hole 3 of the raw material hopper 4 is reduced. Can be changed. This provides the following advantages. That is, for example, there is a case in which the pulverizability is inferior depending on the particle size of the toner and the polymer material used. Increased and improved grindability.

Using the pulverizer shown in FIG. 5, compressed air with a flow rate of 5 m ³ / min was introduced from the nozzle 1 under the same conditions as in Example 1, and 18.5 kg / min. hr
And supplied to the raw material hopper 4 for pulverization.
The crushed material 9 obtained in the crushing chamber 7 is passed through a classifier 11
The fine powder contained therein was recovered. The collected fine powder was measured over time with a particle flow distribution measuring device (Coulter counter). The results are shown in Table 4 below. At this time, the effective area of the pulverized material supply hole 3 is determined by the outlet changing means 22.
At 30%.

[0031]

[Table 4] Time (min) 5 10 15 30 45 60 90 120 Volume average particle size (μm) 5.9 6.1 6.2 6.1 6.0 6.1 6.2 6.1

From Table 4, it can be seen that by controlling the amount of toner supplied to the supply port, it is possible to secure a stable volume average particle diameter even in a small particle size product.

Comparative Example (FIG. 6) Using the conventional collision-type pulverizer shown in FIG.
Compressed air with a flow rate of 5 m3 / min was introduced from the above, and the pulverized material 37 pulverized in the pulverizing chamber 35 was collected through a classifier 39 to recover fine powder contained therein. The collected fine powder was measured over time with a particle flow distribution measuring device (Coulter counter). The results are shown in Table 5 below. At this time, the supplied amount of the crushed material was 25 kg / hr.

[0034]

[Table 5] (Conventional) Time (min) 5 10 15 30 45 60 90 120 Volume average particle size (μm) 7.9 8.4 8.6 8.7 8.8 8.7 8.7 8.8 Content ratio of coarse particles 1.9 1.8 1.9 2.0 1.9 1.8 1.8 1.9

From Table 5, it can be seen that, in the case of this comparative example, the supply amount of the material to be pulverized into the supply hole is unstable, so that (1) the pulverizing capacity is reduced, and (2) the gas suction amount in the hopper above the supply hole Is unstable, resulting in poor classifier balance, leading to a decrease in accuracy.
As a result, the content of coarse particles increases. In this comparative example,
No increase in supply is expected.

[0036]

As is apparent from the above description, according to the present invention, the supply of the material to be ground to the hopper is basically stabilized by the quantitative supply means, so that the supply which has conventionally been a problem The occurrence of excessive or temporary breathing or shortage of supply can be suppressed, thereby improving the pulverization processing capacity and the pulverization accuracy.

In a preferred embodiment, the amount of the material to be ground in the hopper is detected to control the quantitative supply means. Therefore, it is possible to prevent excessive supply, temporary breathing, or shortage of supply, which has been a problem in the related art, thereby further improving the pulverization processing capacity and the pulverization accuracy.

Further, in the apparatus in which the internal state of the classifier is detected to control the quantitative supply means, the supply of the material to be ground to the hopper which has become unstable due to the internal state of the classifier is performed. Can be prevented, so that excessive supply or temporary breathing or shortage of supply, which has been a problem in the past, can be prevented from occurring, whereby the pulverization processing capacity and the pulverization accuracy can be further improved. In addition, it is possible to suppress the coarse particles from entering into the fine particles collected from the classifier, and therefore, it is possible to sharpen the distribution of the particle diameter of the fine particles collected from the classifier.

Further, in the apparatus in which the amount of the material to be ground present in the hopper is detected and the state inside the classifier is detected to control the quantitative supply means, the above-described effects are combined. Therefore, the pulverization processing capability and the pulverization accuracy can be further improved, and the distribution of the particle diameter of the fine particles collected from the classifier can be sharpened.

Further, as another preferred embodiment, in a device provided with a wiping means for preventing the adhesion of the material to be ground and / or blocking the outlet of the hopper, the adhesion inside the hopper is prevented. As a result, the material to be ground can be supplied stably. Further, in the apparatus provided with the outlet changing means for changing the effective opening area of the hopper outlet and the flow path thereof, the supply capacity of the hopper can be adjusted according to the pulverizing performance according to the powder characteristics or the target particle size. Therefore, the crushing ability of the crushing device can be maximized according to the powder characteristics.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a collision type crusher of a first embodiment.

FIG. 2 is an overall configuration diagram of a collision type crusher of a second embodiment.

FIG. 3 is an overall configuration diagram of a collision-type pulverizer according to a third embodiment.

FIG. 4 is an overall configuration diagram of a collision type crusher of a fourth embodiment.

FIG. 5 is an overall configuration diagram of a collision type crusher of a fifth embodiment.

FIG. 6 is an overall configuration diagram of a conventional collision-type pulverizer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Nozzle 2 Accelerator tube 3 Pulverized object supply hole (hopper outlet) 4 Hopper 5 Pulverized object 6 Jet jet 7 Crushing chamber 8 Collision member 8a Collision surface 11 Classifier 13 Container 15 Quantitative feeder 17 Sensor attached to hopper (1st detecting means) 19 Sensor attached to classifier (2nd detecting means) 20 Destroying device 22 Outlet changing means

Continued on the front page (72) Inventor Keiko Watanabe 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Satoru Okano 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company In Ricoh (56) References JP-A-6-226133 (JP, A) JP-A-51-100375 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B02C 19/00- 25/00

Claims (5)

(57) [Claims] 1. An object to be ground supplied from a hopper is carried to a collision chamber by a jet jet, and the object to be ground is made to collide with a collision member in the collision chamber to pulverize the object. A collision-type crushing apparatus having a constant-quantity supply means for supplying the first hopper, a first detection means for detecting an amount of the object to be crushed present in the hopper, and a signal from the first detection means for receiving the signal from the first detection means. A collision-type pulverizer having control means for controlling the constant-quantity supply means such that the amount of the object to be pulverized therein is kept substantially constant. 2. An object to be ground supplied from a hopper is carried to a collision chamber by a jet stream, and the object to be ground is made to collide with a collision member in the collision chamber to pulverize the object. In the collision-type pulverizing device having a quantitative supply means for supplying the liquid, the collision-type pulverization device is constituted by a closed circuit, and in addition to the quantitative supply means, the hopper and the collision chamber, the pulverization performed in the collision chamber A classifier for collecting fine powder from the object, a second detector for detecting the state of the inside of the classifier, and a signal received from the second detector for receiving the powder present in the hopper. A collision-type pulverizer, comprising: a control unit for controlling the constant-quantity supply unit such that the amount of the pulverized material is kept substantially constant. 3. A crushed object supplied from a hopper is carried to a collision chamber by a jet jet, and the crushed object collides with a collision member in the collision chamber to crush the crushed object. In the collision-type pulverizing device having a quantitative supply means for supplying the liquid, the collision-type pulverization device is constituted by a closed circuit, and in addition to the quantitative supply means, the hopper and the collision chamber, the pulverization performed in the collision chamber A classifier for collecting fine powder from the material, further, a first detection means for detecting the amount of the material to be crushed present in the hopper,
A second detecting means for detecting an internal state of the classifier, and receiving signals from the first detecting means and the second detecting means, keeps the amount of the material to be ground in the hopper substantially constant. And a control means for controlling the fixed-quantity supply means so as to fall. 4. The hopper according to claim 1, further comprising a wiping unit for preventing the crushed material from adhering to the inside of the hopper and / or blocking the outlet of the hopper. The collision-type pulverizer according to claim 1. 5. The hopper according to claim 1, further comprising an outlet changing means disposed so as to face the outlet of the hopper and changing an effective opening area of the outlet and a flow path thereof. Collision type crusher.