JPH0549349B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an impingement type air flow crusher and a crushing method using jet air flow (high pressure gas). In particular, the present invention relates to an impingement type air current pulverizer and a pulverization method for efficiently producing toner or colored resin powder for toner used in an electrophotographic image forming method. [Prior Art] Toner or colored resin powder for toner used in an electrophotographic image forming method usually contains at least a binder resin and a colorant or magnetic powder. The toner develops the electrostatic charge image formed on the latent image carrier, and the formed toner image is transferred to a transfer material such as plain paper or plastic film.
The toner image on the transfer material is fixed to the transfer material by a fixing device such as a heat fixing means, a pressure roller fixing means, or a heat pressure roller fixing means. Therefore, the binder resin used in the toner has the property of plastically deforming when heat and/or pressure is applied. Currently, toner or colored resin powder for toner is
Binder resin and colorant or magnetic powder (if necessary,
Furthermore, it is prepared by melt-kneading a mixture containing at least a third component), cooling the melt-kneaded product, pulverizing the cooled product, and classifying the pulverized product. The refrigerant is usually pulverized by coarse (or medium) pulverization using a mechanical impact pulverizer, and then the coarse pulverized powder is pulverized by an impingement air flow pulverizer using a jet air flow. An impingement-type air-flow pulverizer using a jet air flow conveys a powder raw material in a jet air flow, causes the powder raw material to collide with a collision member, and is pulverized by the impact force. Conventionally, as shown in FIGS. 5, 6, and 8, the collision surface 14 of the collision member in such a crusher is perpendicular to the jet airflow direction (the axial direction of the accelerator tube) carrying the powder raw material, or Tilt (e.g. 45°)
(Japanese Patent Application Laid-Open No.
57-50554 and JP-A-58-143853). In the crusher shown in FIG. 5, the powder raw material having a coarse particle size is supplied to the acceleration tube 3 from the input port 1, and the powder raw material is crushed by the jet airflow blown out from the jet nozzle 2 to the collision surface of the collision member 4. 14, is crushed by the impact force, and is discharged to the outside of the crushing chamber from the discharge port 5. However, when the collision surface 14 is perpendicular to the axial direction of the acceleration tube 3, the raw material powder blown out from the jet nozzle 2 and the collision surface 14
There is a high proportion of the powder reflected by the collision surface 14 coexisting in the vicinity of the collision surface 14, and as a result, the powder concentration near the collision surface 14 becomes high, resulting in poor pulverization efficiency. Furthermore, the primary collision is mainly at the collision surface 14, and it cannot be said that the secondary collision with the crushing chamber wall 6 is effectively utilized. Furthermore, in a crusher where the angle of the collision surface is perpendicular to the acceleration tube 3, when crushing thermoplastic resin, fusion and agglomerates are likely to occur due to local heat generation at the time of collision, making it difficult to operate the device stably. This causes a decrease in crushing capacity. Therefore, it has been difficult to use the powder at a high concentration. In the crusher of FIG. 6, since the collision surface 14 is inclined with respect to the axial direction of the acceleration tube 3, the powder concentration near the collision surface 14 is lower than that of the crusher of FIG. The crushing pressure is dispersed and reduced. Furthermore, it cannot be said that the secondary collision with the crushing chamber wall 6 is effectively utilized. As shown in FIGS. 6 and 7, when the angle of the collision surface 14 is inclined at 45 degrees with respect to the acceleration tube, the above-mentioned problems when crushing thermoplastic resin are reduced. However, the impact force used for crushing during collision is small, and there is less crushing due to secondary collision with the crushing chamber wall 6, so the crushing capacity is 1/2 to 1/2 compared to the crusher shown in Fig. 4. The crushing ability drops to 1.5. In the pulverizer shown in FIG. 8, since the collision surface 14 is inclined downward with respect to the axial direction of the accelerator tube, the powder concentration near the collision surface 14 is lower than that in the pulverizer shown in FIG. 5. Furthermore, although the secondary collision with the crushing chamber wall 6 is effectively utilized, as shown in FIG. 9, the secondary collision with the crushing chamber wall 6 is substantially only utilized on the lower wall surface. Therefore, a crusher and a crushing method with even better crushing efficiency are desired. [Object of the Invention] An object of the present invention is to provide an impingement-type air current pulverizer and a pulverizing method in which the above-mentioned problems are solved. An object of the present invention is to provide an impingement type air flow mill and a milling method for efficiently milling powder mainly composed of thermoplastic resin. An object of the present invention is to provide an impingement type air flow mill and a milling method in which fusion of powder raw materials and milled powder in a powder chamber is less likely to occur. An object of the present invention is to provide an impingement type air flow mill that suppresses the fusion of the powder raw material and the pulverized powder and generates fewer aggregates and coarse particles even when the throughput of the powder raw material is increased. It's about doing. An object of the present invention is to efficiently crush powder raw materials mainly composed of thermoplastic resins such as polyester resins or styrene resins (for example, styrene-acrylic ester copolymers or styrene-methacrylic ester copolymers). The purpose of the present invention is to provide an impingement type airflow crusher. SUMMARY OF THE INVENTION An object of the present invention is to provide an impingement type air current crusher that can efficiently produce toner or colored resin particles for toner used in copying machines and printers having heating and pressure roller fixing means. An object of the present invention is to provide an impingement type air flow mill that can efficiently pulverize resin particles having an average particle size of 30 to 1000 μm to an average particle size of 5 to 15 μm. [Summary of the Invention] The present invention provides an acceleration tube for transporting and accelerating colored resin powder with high-pressure gas, a crushing chamber, and a collision member for crushing the colored resin powder ejected from the acceleration tube by collision force. The acceleration tube has a pipe passage whose cross-sectional area perpendicular to the axial direction of the acceleration tube gradually increases toward the exit of the acceleration tube, and the collision member faces the exit of the acceleration tube. The colored resin powder is provided in the crushing chamber, and the colored resin powder is crushed by the collision surface of the collision member, and after the collision, it is dispersed in substantially the entire circumferential direction, and the dispersed colored resin powder causes a secondary collision with the crushing chamber wall. so that the tip of the collision surface of the collision member has a conical shape with an apex angle of 120 to 170°, and the inner diameter of the acceleration tube outlet has an inner diameter of 10 to 100 mm, which is smaller than the diameter b of the collision member. , The distance a between the accelerator tube outlet and the tip of the collision member is
A collision type airflow characterized in that the diameter b of the collision member is 0.5 to 2 times, and the shortest distance c between the collision member and the wall of the crushing chamber is set to 0.1 to 1 time the diameter of the collision member. Regarding the crusher. Furthermore, the present invention conveys colored resin powder with high pressure gas in an acceleration tube to accelerate the colored resin powder,
In a pulverization method, colored resin powder is discharged from an accelerating tube outlet into a pulverizing chamber, and the colored resin powder is pulverized by colliding with a collision surface of a collision member provided in the pulverizing chamber opposite to the accelerating tube outlet. The acceleration tube has a pipe passage whose cross-sectional area perpendicular to the axial direction of the acceleration tube gradually increases toward the exit of the acceleration tube, and the inside diameter of the exit of the acceleration tube is smaller than the diameter b of the collision member. 100mm, and the distance a between the accelerator tube outlet and the tip of the collision member is
The diameter b of the collision member is 0.5 to 2 times, the shortest distance c between the collision member and the crushing chamber wall is set to 0.1 to 1 time the diameter of the collision member, and the particle is accelerated in the pipe passage. The tip of the collision surface of the colored resin powder discharged from the accelerator tube outlet has an apex angle of 120 to 170°.
The present invention relates to a method for pulverizing colored resin powder, characterized in that the colored resin powder is pulverized by colliding with a collision member having a conical shape, and the colored resin powder after the collision is further pulverized by secondary collision with a wall of a pulverizing chamber. [Detailed Description of the Invention] The collision type airflow crusher of the present invention efficiently crushes thermoplastic resin powder or powder mainly composed of thermoplastic resin to the order of several μm using high-speed airflow. can do. The present invention will be explained based on the accompanying drawings. FIG. 1 is a diagram showing a schematic cross-sectional view of the pneumatic pulverizer of the present invention and a flowchart of a pulverization method that combines a pulverization process using the pulverizer and a classification process using a classifier. The powder raw material 7 to be crushed is supplied to the acceleration tube 3 from the powder raw material input port 1 provided in the crusher wall 11 above the acceleration tube 3 . Compressed gas such as compressed air is introduced into the acceleration tube 3 from the compressed gas supply nozzle 2, and the powder raw material 7 supplied to the acceleration tube 3 is instantly accelerated to have a high velocity. The powder raw material 7 discharged from the acceleration tube outlet 13 into the crushing chamber 8 at high speed collides with the collision surface 14 of the collision member 4 and is crushed. In the crusher shown in FIG. 1, since the collision surface 14 has a conical shape with an apex angle of 120°, the crushed powder is dispersed substantially in the entire circumferential direction, and the crushing chamber wall 6 and the secondary It causes a collision and is further shattered. FIG. 2 is a diagram schematically showing a cross section along the A-B plane of the collision type air flow crusher shown in FIG. ing. Second
From the figure, it can be seen that in the air flow type crusher of the present invention, the secondary collision of powder on the crushing chamber wall 6 is effectively utilized. Furthermore, in the crusher of the present invention, the powder is well spread in the axial direction of the collision member on the collision surface 14 as shown in FIG. 14, so that the crushing chamber wall 6 is widely utilized for secondary collisions. Therefore, since the concentration of powder near the collision surface 14 does not become high, the powder processing efficiency can be improved, and it is possible to satisfactorily suppress the fusion of powder at the collision surface 14. The powder introduced into the crushing chamber 8 is crushed by a first collision on the collision surface 14, and then further crushed by a second collision on the crushing chamber wall 6, and in some cases, the crushed powder is is further crushed by tertiary (and quaternary) collisions with the crushing chamber wall 6 before being conveyed to the discharge port 5.
The powder discharged from the outlet 5 is classified into fine powder and coarse powder by a classifier 24 such as a fixed wall air classifier. The classified fine powder can be used as a product as it is, or if necessary, it can be further classified and used as a product. The classified coarse powder is charged into the powder raw material input port 1 together with the newly input powder raw material. A case in which the pulverized powder is used as a toner of an electrophotographic developer or colored resin particles for toner will be further described. The toner is composed of powder having an average particle size of 5 to 20 μm. The toner may be formed from toner colored resin particles themselves, or may be formed from toner colored resin particles and an additive such as silica. The colored resin particles for toner are composed of a binder resin and a colorant or magnetic powder, and may further contain additives such as a charge control agent and/or an offset prevention agent, if necessary. As the binder resin, a styrene resin, an epoxy resin, or a polyester resin having a glass transition point Tg of 50 to 120° C. is used. As the coloring agent, various dyes or pigments such as carbon black, nigrosine dyes or phthalocyanine pigments are used. As the magnetic powder, powder of metal or metal oxide, such as iron, magnetite, and ferrite, which is magnetized by a magnetic field, is used. The mixture of binder resin and colorant (or magnetic powder) is melt-kneaded, the melt-kneaded product is cooled, and the cooled material is coarsely or medium-pulverized to have an average particle size of 30 to
A 1000 μm powder raw material is prepared. The powder raw material input from the powder raw material input port 1 is 3 to 10 kgf/cm ²
The compressed air having a pressure of The powder raw material having a high speed of 300 to 400 m/sec is discharged into the grinding chamber 8 from the acceleration tube outlet 13. Since the collision member 4 is easily worn out, it is made of ceramic such as alumina oxide or stainless steel and is coated with ceramic by thermal spraying on the surface of the base. Similarly, the grinding chamber walls are
Preferably, the surface is made of at least ceramic. The collision member 4 has a cylindrical or polygonal cylindrical shape, and in the case of a cylindrical cylinder, one having a diameter b of usually 40 to 500 mm is used. The tip of the collision member 4 facing the acceleration tube outlet 13 has a conical shape. The tip of the collision member 4 has an apex angle of 110° to 175° (preferably 120° to 170°). apex angle of cone
If the apex angle of the cone is less than 110°, the impact force during crushing will be small and the powder efficiency will decrease. On the other hand, if the apex angle of the cone exceeds 175°, the powder raw material will easily fuse to the surface of the collision member.
Therefore, it is difficult to increase the throughput of powder. The acceleration tube outlet 13 usually has an inner diameter of 10 to 100 mm, and preferably has an inner diameter smaller than the diameter b of the collision member 4. It is preferable that the tip of the collision surface 14 of the collision member 4 and the central axis of the acceleration tube 3 are substantially aligned (with a deviation of 10 mm or less) from the viewpoint of uniform pulverization. The distance a between the acceleration tube outlet 13 and the tip of the collision member 4 is preferably 0.5 to 2 times the diameter b of the collision member 4. If it is less than 0.5 times, over-pulverization tends to occur, and if it exceeds 2 times, the grinding efficiency tends to decrease. The shortest distance c between the collision member 4 and the crushing chamber wall 6 is preferably 0.1 to 1 times the diameter b of the collision member 4. If it is less than 0.1 times, over-grinding tends to occur.
Furthermore, the powder tends not to flow smoothly. On the other hand, if it exceeds 1, the pulverization efficiency tends to decrease. Grinding chamber wall 6 with which powder collides secondary
It is preferable to have a U-shape as shown in FIG. 2 from the viewpoint of preventing the powder from adhering and making the grinding uniform. The shape of the crushing chamber wall 6 can be rectangular or square as shown in FIG.
Compared to the U-shaped case shown in FIG. 2, fusion of powder is more likely to occur. FIG. 12 shows a collision type airflow crusher having another aspect of the present invention, in which a discharge port for crushed powder is provided in the axial direction of the collision member 4. FIGS. 3 and 4 show a crusher in which the apex angle of the conical portion is 160° or 170°. When using the collision type air flow crusher of the present invention, the fifth
If the crushing efficiency of the crusher shown in the figure is 1, it is possible to achieve a crushing efficiency of about 1.2 to about 3.3. Hereinafter, the present invention will be explained in detail based on Examples and Comparative Examples. Example 1 Powder was pulverized using an impingement type air flow pulverizer shown in FIGS. 1 and 2 of the accompanying drawings. A fixed wall type wind classifier was used as a classification means to classify the pulverized powder into fine powder and coarse powder. The collision type air flow crusher has a cylindrical collision member 4 made of ammonium oxide ceramic with a diameter b of 60 mm, and the tip of the collision member 4 has an apex angle of 120°.
It had a conical shape. The inner wall of the crushing chamber 8 was coated with ceramic. Accelerator tube outlet 13
The inner diameter of the accelerator tube 3 was 25 mm, and the central axis of the accelerator tube 3 and the tip of the collision member 4 coincided. The closest distance a from the acceleration tube outlet 13 to the collision surface 14 is 60 mm,
The closest distance c between the collision member 4 and the crushing chamber wall 6 is 20 mm.
It was hot. The cross section of the impingement type air flow crusher along plane A-B had a U-shape as shown in FIG. The distances between the collision member 4 and the left and right and lower crushing chamber walls 6 are as follows:
It was 20 to about 40 mm. The following material was used as raw material 7. Polyester resin 100 parts by weight (Weight average molecular weight (Mw) = 50000; Tg = 60°C) Phthalocyanine pigment 6 parts by weight Low molecular weight polyethylene 2 parts by weight Negative charge control agent 2 parts by weight (Azo metal complex) Mixture of the above formulation Approximately 180 toner raw materials
After melting and kneading for about 1.0 hours at °C, it is cooled and solidified.
The powder was coarsely ground into particles and used as a powder raw material. When the powder raw material is supplied from the input port 1 at a rate of 30 kg/hour, the powder raw material is accelerated in the acceleration tube 3 by compressed air (6 kgf/cm ² ) blown out from the nozzle 2. The powder raw material 7 was discharged from the tube outlet 13 into the crushing chamber 8, and struck against the collision surface 14, and was crushed by the impact force. At the same time, due to the conical collision surface 14 with an inclination of 120 degrees, the collided powder raw material was dispersed in the entire circumferential direction and secondarily collided with the opposing crushing chamber wall 6, where it was further crushed. The pulverized powder raw material was smoothly conveyed to the classifier 24 from the discharge port 5, the fine powder was removed as classified powder, and the coarse powder was again input from the input port 1 together with the powder raw material. Ground powder with a weight average particle size of 12 μm was collected as fine powder at a rate of 30 Kg/hour. In this way, since the collision surface of the collision member 4 has a conical shape with an inclination of an apex angle of θ120 degrees, the collided powder raw material is dispersed in the entire circumferential direction and causes a secondary collision with the opposing crushing wall. . Therefore, since no fusion, agglomerates, or coarse particles occur near the collision member, the powder concentration does not increase, and furthermore, due to secondary collisions, it has been confirmed that the crushing capacity is much higher than before. Ta. Example 2 The same powder raw material as in Example 1 was pulverized in the same manner as in Example 1 using a collision member having a conical collision surface with an inclined apex angle of θ 160 degrees as shown in FIG. As in Example 1, it was confirmed that the dust concentration near the collision surface during crushing did not increase and secondary collisions occurred, so that the crushing capacity was much higher than that of the conventional example. The amount of powder raw material input was adjusted according to the amount to be processed. Example 3 The same powder raw material as in Example 1 was pulverized in the same manner as in Example 1 using a collision member having an inclined conical collision surface with an apex angle of 170 degrees as shown in FIG. It was confirmed that the dust concentration near the collision surface does not increase during the collision, and because secondary collisions occur, the crushing capacity is much higher than before. Comparative Example 1 The same powder raw material as in Example 1 was pulverized using a conventional impingement type air flow pulverizer shown in FIG. In the crusher, a planar impact surface 14 that is perpendicular to the acceleration tube 3
The material was crushed in the same manner as in Example 1 using the collision member 4 having the following. Since the powder raw material that collided with the collision surface 14 was reflected in a direction opposite to the discharge direction, the powder concentration near the collision surface became significantly high. Therefore, when the powder raw material supply rate exceeds 10 kg/hour, fusion, agglomerates, and coarse particles begin to form on the collision member, and the fused materials sometimes clog the acceleration tube outlet 13 and the classifier. . Therefore, it was necessary to reduce the grinding throughput to 10 kg per hour, which became the limit of the grinding capacity. Comparative Example 2 The same powder raw material as in Example 1 was used in Figs. 6 and 7.
It was pulverized using the impingement type air flow pulverizer shown in the figure. When pulverization was performed in the same manner as in Example 1 using a collision member having a collision surface of 45 degrees in the crusher, the powder raw material that collided with the collision surface was moved in a direction away from the acceleration tube outlet 13 compared to Comparative Example 1. No fusion or agglomeration occurred because the light was reflected to However, when colliding,
Since the impact force was weak, the pulverization efficiency was poor, and only about 10 kg of fine powder with a weight average particle size of 12 μm could be obtained per hour. Comparative Example 3 The same powder raw material as in Example 1 was pulverized using an impingement type air flow pulverizer shown in FIGS. 10 and 11. In the crusher, a collision member having a conical collision surface with an inclination of an apex angle of 90 degrees was used, and Example 1
When the material was pulverized in the same manner as above, the powder raw material that collided with the collision surface was dispersed backwards, so that no fusion or agglomeration occurred. However, since the impact force is weak during collision, the crushing efficiency is poor, and the weight average particle size
Only about 10 kg of 12 μm fine powder was obtained per hour. Comparative Example 4 The same powder raw material as in Example 1 was prepared in Figs. 8 and 9.
It was pulverized using the impingement type air flow pulverizer shown in the figure. When pulverization was performed in the same manner as in Example 1 using a collision member having a 45-degree collision surface in the pulverizer, no fusion or agglomerates were formed. However, the weight average particle size
Only about 1.1 kg of 12 μm fine powder was obtained per hour. The results of Examples 1 to 3 and Comparative Examples 1 to 4 are shown in Table 1 below.

[Table] Example 4 The following materials were used as powder raw materials. Styrene butyl acrylate 100 parts by weight (Mw=200000; Tg=60℃) Magnetic powder 60 parts by weight (magnetite, average particle size 0.3μ) Low molecular weight polyethylene 2 parts by weight Negative charge control agent 2 parts by weight From the mixture of the above formulation Approximately 180 toner raw materials
After melt-kneading for about 1.0 hours at °C, the mixture was cooled and solidified, and the solid material was coarsely ground into particles of 100 to 1000 μm using a hammer mill, which was used as a powder raw material. Powder raw material was supplied at a rate of 9.1 kg/hour from the input port 1, compressed air of 6 kgf/cm ² was introduced from the nozzle 2, and the material was pulverized by the collision type air flow crusher shown in Figures 1 and 2. The pulverized powder was classified into fine powder and coarse powder by a classifier 24. As a fine powder, weight average particle size
12 μm powder was collected at a rate of 9.1 Kg per hour. Example 5 The same powder raw material as in Example 4 was produced using an impact type air flow mill shown in FIG. When the material was pulverized in the same manner as in 4, fine powder with a weight average particle size of approximately 12 μm was collected at a rate of 9.8 kg per hour. The amount of powder raw material input was adjusted according to the amount to be processed. Example 6 The same powder raw material as in Example 4 was used in the collision type air flow mill shown in FIG. When pulverized in the same manner as in Example 4, fine powder with a weight average particle size of about 12 μm was collected at a rate of 8.4 kg per hour. Comparative Example 5 When the same powder raw material as in Example 4 was pulverized using an impingement type air flow pulverizer shown in FIG. 5, only 7 kg of fine powder with a weight average particle diameter of about 12 μm was collected per hour. Comparative Example 6 The same powder raw material as in Example 4 was prepared in Figs. 6 and 7.
When the material was pulverized using the impingement air flow pulverizer shown in the figure, only 4.2 kg of fine powder with a weight average particle size of approximately 12 μm was collected per hour. Comparative Example 7 When the same powder raw material as in Example 4 was pulverized using the collision type airflow pulverizer shown in Figs. 10 and 11, fine powder with a weight average particle diameter of about 12 μm was produced at a rate of 7.7 kg per hour. only was collected. The results of Examples 4 to 6 and Comparative Examples 5 to 7 are shown in Table 2 below.

[Table] Example 7 A powder raw material was pulverized using an impact type air flow pulverizer shown in FIGS. 12 and 13. The distance a from the accelerator tube outlet to the collision surface is 50 mm, the diameter b of the collision member is 60 mm, the distance c from the collision surface to the crushing chamber wall is 20 mm, and the apex angle θ of the collision surface is 160 degrees. It was hot. Furthermore, the shape of the crushing chamber wall was circular, and the discharge port 5 was provided in the axial direction of the collision member. The following materials were used as powder raw materials. Styrene-acrylic acid ester resin 100 parts by weight Magnetite 60 parts by weight Low molecular weight polyethylene 2 parts by weight Negative charge control agent 2 parts by weight Approximately 180 parts of toner material consisting of the mixture of the above formulation was used.
After melting and kneading for about 1.0 hours at °C, the mixture was cooled and solidified, and coarsely ground into particles of 100 to 1000 μm using a hammer mill, which was used as a powder raw material. When the powder raw material is supplied from the input port 1, the powder raw material is struck against the collision surface of the collision member 4 by the compressed air blown out from the nozzle 2, and is pulverized by the impact force. At the same time, the collision surface of this collision member 4 has a conical shape with an inclination of 160 degrees, and disperses the collided powder raw material in the entire circumferential direction, causing a secondary collision with the opposing crushing chamber wall 6. , where it was further shattered. The crushed powder raw material is smoothly conveyed to the classifier from the discharge port 5, and the fine powder is removed as a product.
The coarse powder was again charged from the input port 1 together with the powder raw material. Since fusion, agglomerates, and coarse particles do not occur, the crushing ability does not decrease, making it possible to increase the powder concentration during crushing, and maintaining strong impact force until secondary collision. Overall, the crushing efficiency was improved by 80 to 100% compared to the case where the collision surface is perpendicular to the accelerator tube. Example 8 The same powder raw material as in Example 7 was pulverized using the collision type air flow pulverizer shown in FIGS. 14 and 15. In Example 8, similar to Example 7, fusion, aggregates,
Since coarse particles are not produced, the crushing ability does not decrease, making it possible to increase the powder concentration during crushing, and maintaining a strong impact force until the time of secondary collision. Overall, the crushing efficiency was improved by 20 to 50% compared to the case where the collision surface is perpendicular to the accelerator tube. [Effects of the Invention] As explained above, by forming the tip of the collision member into a specific conical shape, it is possible to prevent the occurrence of fusion, agglomerates, coarse particles, etc. during pulverization of powder raw materials.
Enables stable operation of equipment. Moreover, strong impact force can be maintained until the secondary collision of powder raw materials. Therefore, the conventional crushing capacity can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a diagram schematically showing the cross section and the crushing/classifying process of the collision type air flow crusher of the present invention, in which the conical collision surface of the collision member has an apex angle of 120°,
FIG. 2 is a diagram schematically showing a cross section of the crusher shown in FIG. 1 along the line A-B. Figures 3 and 4
The figure shows that the apex angle of the conical collision surface of the collision member is 160°.
It is a diagram schematically showing the cross section of the collision type air flow crusher of the present invention having an angle of 170° and the crushing/classifying process. FIG. 5 is a diagram schematically showing a cross section and a crushing/classifying process of a collision type air flow crusher as a comparative example, in which the collision surface of the collision member is perpendicular to the axial direction of the accelerator tube. FIG. 6 shows that the collision surface of the collision member is inclined upward at 45° with respect to the axial direction of the accelerator tube.
FIG. 7 is a diagram schematically showing a cross section and a crushing/classifying process of an impingement type air flow crusher as a comparative example, and FIG. 7 is a diagram schematically showing a cross section of the collision type air flow crusher shown in FIG. FIG. Figure 8 schematically shows the cross section and crushing/classifying process of a collision type airflow crusher as a comparative example, in which the collision surface of the collision member is inclined downward at 45 degrees with respect to the axial direction of the accelerating tube. FIG. 9 is a diagram schematically showing a cross section of the collision type air flow crusher shown in FIG. 8 along the line A-B. In FIG. 10, the apex angle of the conical collision surface of the collision member is 90°. FIG. 11 is a diagram schematically showing the cross section and the crushing/classifying process of an impact type air flow crusher as a comparative example; FIG.
FIG. 2 is a diagram schematically showing a cross section of the collision type air flow crusher shown in the figure, taken along the line A-B. Figures 12 to 1
FIG. 5 is a diagram schematically showing the cross section and the crushing/classifying process of another embodiment of the collision type air flow crusher of the present invention. DESCRIPTION OF SYMBOLS 1... Powder raw material input port, 2... Compressed gas supply nozzle, 3... Accelerator tube, 4... Collision member, 5... Discharge port, 6... Grinding chamber wall, 7... Powder raw material, 8 ……
Grinding chamber, 11...Crusher wall, 13...Acceleration tube outlet, 14...Collision surface, 24...Classifier, {a...
Distance between the acceleration tube outlet and the collision member, b...The diameter of the collision member, c...The shortest distance between the collision member and the crushing chamber wall}.

Claims (1)

[Claims] 1. An acceleration tube for transporting and accelerating colored resin powder with high-pressure gas, a crushing chamber, and a collision member for crushing the colored resin powder ejected from the acceleration tube by collision force. The accelerating tube has a pipe passage whose cross-sectional area perpendicular to the axial direction of the accelerating tube gradually increases toward the outlet of the accelerating tube, and the collision member is arranged in the crushing chamber opposite to the outlet of the accelerating tube. The colored resin powder is pulverized by the collision surface of the collision member, and after the collision, the colored resin powder is dispersed in substantially the entire circumferential direction, and the dispersed colored resin powder causes a secondary collision with the wall of the pulverization chamber. The tip of the collision surface of the collision member has a conical shape with an apex angle of 120 to 170°, and the acceleration tube outlet has an inner diameter of 10 to 100 mm, which is smaller than the diameter b of the collision member. The distance a between the tube outlet and the tip of the collision member is
A collision type airflow characterized in that the diameter b of the collision member is 0.5 to 2 times, and the shortest distance c between the collision member and the wall of the crushing chamber is set to 0.1 to 1 time the diameter of the collision member. Crusher. 2. The colored resin powder is conveyed by high pressure gas in the acceleration tube, the colored resin powder is accelerated, and the colored resin powder is discharged from the acceleration tube outlet into the crushing chamber. In the pulverization method of pulverizing the colored resin powder by colliding it against the collision surface of a collision member, the acceleration tube is a tube whose cross-sectional area perpendicular to the axial direction of the acceleration tube gradually increases toward the exit direction of the acceleration tube. The acceleration tube outlet has an inner diameter of 10 to 100 mm smaller than the collision member diameter b, and the distance a between the acceleration tube outlet and the tip of the collision member is:
The diameter b of the collision member is 0.5 to 2 times, the shortest distance c between the collision member and the crushing chamber wall is set to 0.1 to 1 time the diameter of the collision member, and the particle is accelerated in the pipe passage. The tip of the collision surface of the colored resin powder discharged from the accelerator tube outlet has an apex angle of 120 to 170°.
1. A method for pulverizing colored resin powder, which comprises colliding the powder with a collision member having a conical shape to crush it, and pulverizing the colored resin powder after the collision by secondly colliding with a wall of a pulverizing chamber.