GB2276570A - A collision type supersonic jet crusher - Google Patents

Abstract

The jet crusher comprises a crushing room 37, a supersonic jet flow path 3, and a crushing collision member 40 disposed in the crushing room 37 and having a right circular cone 38 for dispersing a supersonic jet flow of material from the supersonic jet flow path, and a disk 39 providing an annular collision surface as a primary collision surface; efficiency is improved by provision of annular member 2 and/or inclination guide member 21. Thus in Figure 1, a right circular conical trapezoidal portion 1 of member 2 has the same solid angle as the crushing collision member and has an apex angle between 30 DEG and 150 DEG . Alternatively, or in addition, the crushing room 37 is provided with guide member 21 having an inclined surface at an angle between 10 DEG and 70 DEG with respect to the axis of the crushing room in a rear portion thereof. <IMAGE>

Description

A COLLISION TYPE SUPERSONIC JET CRUSHER The present invention relates to a collision type supersonic jet crusher in which a coarse particle is crushed into a micro particle by using a jet stream due to a high pressure.

In order to obtain a micro particle in a micron unit, especially the micro particle having a thermal plasticity, such as a thermal plasticity resin powder, and a toner and the like, the coarse particle crushed coarsely is micronized by using the collision type supersonic jet crusher.

These crushers are disclosed, for example, in Japanese Utility Model Application Laying Open (KOKAI) No. 51-100374, Japanese Utility Model Application Laying Open (KOKAI) No. 51-100375 and the like. Also, improved type crushers are disclosed in Japanese Utility Model Application Laying Open (KOKAI) No. 1-148740, Japanese Patent Application Laying Open No. 2-68155, Japanese Utility Model Application Laying Open (KOKAI) No. 3-19543, Japanese Patent Application (KOKOKU).

No. 4-3837 and Japanese Patent Application Laying Open (KOKAI) No. 3-1162.

A general arrangement of the collision type supersonic jet crusher is shown in Fig. 7. A main portion of the crusher in Fig. 7 is almost identical with the crushers described in Japanese Utili ty Model Application Laying Open (KOKAI) No. 1- 148740, Japanese Patent Application Laying Open No. 2-68155 and Japanese Utility Model Application Laying Open (KOKAI) No. 3-19543.

In Fig. 7, a crushed material Ta, which is made of a thermal plasticity resin and the like and is crushed coarsely previously, is thrown from a raw material throwing portion 31, and is fed, through a path 32, a classification room 33 and a path 34, to a jet stream path 35.

A nozzle 36 is disposed under the path 34. A high pressure air is injected from the nozzle 36 because of an inflow of a compressed air. Thereby, there is a jet flow resulting from a supersonic air, in the jet path 35. A crushing collision member 40 is disposed in a crushing room 37 so as to oppose to the nozzle 36. The collision member 40 comprises an assembly of a right circular cone 38 and a disk 39.

The crushed material Ta is fed through the path 34 to a supply port 35a situated in front of the nozzle 36. Then, the crushed material Ta rides on the jet flow, flies at a high speed (a supersonic speed), and is guided to a conical surface of the right circular cone 38 of the collision member 40. Then the material to be crushed Ta primarily collides against a circular flat surface (the disk 39), then secondary collides against an inner surface 37a of the crushing room 37, and thereby is crushed in a form of the micro particle. In this way, most of the material to be crushed Ta becomes a micro powder Tp in a micron unit. Then, the micro powder Tp is joined with the material to be crushed Ta in the path 32 from the crushing room 37 through a path 41, and then a joined flow of the material to be crushed Ta and the macro powder Tp is to the classification room 33.

In the classification room 33, the micro powder Tp is separated from a coarse particle, which is left without being crushed sufficiently in the crushing room 37, and the crushed material Ta, and the micro powder Tp is recovered as a product Ts. The crushed material Ta and the coarse particle are fed again through the path 34 to the jet path 35 and crushed in the crushing room 37.

The crushed material is crushed as mentioned above. This crushing is performed in such a manner that the crushed material collides.against the crushing collision member 40 and the inner surface 37a of the crushing room 37. Therefore, this type of the supersonic jet crusher is called the collision type supersonic jet crusher.

In the equipment, the micro powder having a particle diameter equal to or less than 100 Atm m is classified, selected and used as the product.

However, in this case, it is known that a feeding amount of the crushed material, a pressure and a flow rate of a high pressure crushing air and a shape of the crushing collision member have an effect on a performance required for the equipment, for example, a particle diameter of an obtained toner, its yield and the like.

The crushing collision member 40 is disposed in a direction orthogonal to a jet flow direction.

However, a construction having a collision surface consisting of a right circular conical guide surface as mentioned above (also having a crushing effect resulting from a collision) and a circular flat surface lying concentrically at a lower edge of the guide surface (hereinafter, this is sometimes described as a circular conical type collision plate) is most advantageous. Thereby, If the collision member is used, it is possible to obtain a crushing product in which a distribution of a particle size is sharp.

On the other hand, prior general crushing equipments are classified roughly, based on a crushing means, into (1) a striking type (for example, a hammer mill, an emperor breaker and the like), (2) a milling and compressing type (for example, a roller mill, a tower mill and the like), (3) a compressing type (for example, a jaw crusher, jailetry crusher and the like), (4) a striking and shearing type (for example, a ball mill, a rod mill and the like), and (5) an impacting and shearing type (for example, a jet mill, a jetmizer and the like).

However, many of selection and use of these crushing equipments are controlled by a thermal characteristic of the crushed material in addition to a crushing ability (a processing ability of obtaining the micro particle in the distribution.

of the constant particle size) and a crushing efficiency. Especially, for example, in the crushed material, such as a resin powder, the toner and the like made of principally a resin having the thermal plasticity, a heat is generated and a temperature is increased because of a sharp energy increase on the crushing surface at the time of crushing. As a result, deficiencies, such as an aggregation and a fixing between crushed particles, a fusion into the crushing surface or a powder contacting portion and the like of the crushing equipment are generated. Therefore, it is not preferable to use the crushing equipment utilizing the means of the striking, the milling, the compressing and the like.

In these crushed materials, it is possible to use as a crushing medium in large quantity a cooled compressed gas or a low temperature gas having a great cooling effect as a crushing medium. Therefore, it is preferable to use the crushing equipment utilizing the means of the impacting and the shearing, that is, the collision type supersonic jet crusher, such as the jet mill, the jetmizer and the like. Furthermore, a desire of obtaining the micro particle having the thermal plasticity by means of a high efficient crushing at a low cost is still strong. Then, to realize it by means of the collision type supersonic jet crusher is considered as an advantageous method.

In a prior collision type supersonic jet crusher, in a case where the circular conical type collision plate is used, because of a Coanda effect on the right circular conical guide surface, after most of the crushed materials collide against the crushing surface with the circular flat surface, a flow of the crushed materials is converted suddenly in a direction perpendicular to the nozzle 36 along the circular flat surface while keeping their speeds.

However, simultaneously, due to a shape of the crushing room 37, in some crushed materials, there is a disturbance (a turbulent flow) of a crushing flow before and behind the circular conical collision plate. Therefore, there is a problem that the Coanda effect can not be given sufficiently in the right circular conical guide surface.

SUMMARY OF THE INVENTION In order to solve the problems mentioned above, it is therefore an object of the present invention to provide a collision type supersonic jet crusher having a high crushing process ability by improving a shape of an inner surface of a crushing room, most effectively utilizing a Coanda effect on a right circular conical guide surface and preventing a disturbance of a crushing flow.

The object of the invention can be achieved by a collision type supersonic jet crusher comprising according to the first invention: a crushing room; a supersonic jet flow path communicated with said crushing room for injecting into said crushing room said material to be crushed; a crushing collision member disposed in said crushing room concentrically with and oppositely to said nozzle, said crushing collision member having a right circular conical surface for dispersing a supersonic jet flow of said material from said supersonic jet flow path, and an annular collision surface as a primary collision surface lying concentrically on a bottom edge portion of said right circular conical surface, said crushing room being adapted to constitute at an inner surface thereof a secondary collision surface of said material, wherein said crushing room is provided with, at a front portion thereof, a right circular conical trapezoidal concave surface having the same solid angle as said right circular conical surface of said crushing collision member and having an apex angle between 30' and 150' with respect to a longitudinal sectional shape, said right circular conical trapezoidal concave being formed concentrically and surrounding said right circular conical surface.

In the collision type supersonic jet crusher according to the first invention, the right circular conical surface of the crushing collision member is surrounded by the right circular conical trapezoidal concave surface, as mentioned above.

Furthermore, the apex angle between these right circular conical surface and the right circular conical trapezoidal concave surface is the same angle within a range between 30 and 150'. Thereby, the supersonic jet flow which is supplied into the crushing room can be dispersed along the right circular conical surface without being disturbed.

Therefore, the Coanda effect on the right circular conical surface is largely improved. As a result, the crushing effect on the circular collision surface of the crushing collision member, and the inner surface of the crushing room is largely improved.

By the way, the improved effect of the crushing power (the improved action of the Coanda effect) is insufficient in a case where the apex angle between the right circular conical surface and the right circular conical trapezoidal concave surface is without the range between 30 and 150'.

In accordance with the collision type supersonic jet crusher according to the first invention, the Coanda effect on the right circular cone is largely improved, and the disturbance of the supersonic jet flow is reduced, by providing the right circular conical trapezoidal concave surface which surrounds the right circular cone of the crushing collision member in the crushing room. Therefore, it is possible to obtain a crushed micro powder having a sharp particle size distribution with a high crushing efficiency, and to largely improve a processing power of the crusher.

The object of the invention can be achieved by a collision type supersonic jet crusher according to the second invention, comprising: a crushing room; a supersonic jet flow path communicated with said crushing room for injecting into said crushing room said material to be crushed; a crushing collision member disposed in said crushing room concentrically with and oppositely to said nozzle, said crushing collision member having a right circular conical surface for dispersing a supersonic jet flow of said material from said supersonic jet flow path, and an annular collision surface as a primary collision surface lying concentrically on a bottom edge portion of said right circular conical surface, said crushing room being adapted to constitute at an inner surface thereof a secondary collision surface of said material, wherein said crushing room is provided with an inclination guide member having an inclination surface at an angle between 10' and 70 with respect to an axis direction of said crushing room, in a rear portion thereof, thereby to form an upward flow path or a downward flow path.

In the collision type supersonic jet crusher according to the second invention, the upward flow path or the downward flow path of the supersonic jet flow is formed by providing the inclination guide member (the member also has the crushing action by the collision) having a predetermined inclination angle. Therefore, the Coanda effect on the right circular conical surface is largely improved. As a result, the crushing action is largely improved.

By the way, the improved effect of the crushing power (the improved action of the Coanda effect) is insufficient in a case where the inclination angle of the inclination surface is without the range between 10' and 70'.

In accordance with the collision type supersonic jet crusher according to the second invention, a guide surface of the supersonic jet flow is formed from the inclination surface in the rear portion of the crushing room. Therefore, it is possible to obtain an action and an effect similar to a case of the claim 1. As a result, there is an effect that the processing power of the crusher is largely improved.

The object of the invention can be achieved by a collision type supersonic jet crusher according to the third invention, comprising: a crushing room; a supersonic jet flow path communicated with said crushing room for injecting into said crushing room said material to be crushed; a crushing collision member disposed in said crushing room concentrically with and oppositely to said nozzle, said crushing collision member having a right circular conical surface for dispersing a supersonic jet flow of said material from said supersonic jet flow path, and an annular collision surface as a primary collision surface lying concentrically on a bottom edge portion of said right circular conical surface, said crushing room being adapted to constitute at an inner surface thereof a secondary collision surface of said material, wherein said crushing room is provided with, at a front portion thereof, a right circular conical trapezoidal concave surface having the same solid angle as said right circular conical surface of said crushing collision member and having an apex angle between 30' and 150' with respect to a longitudinal sectional shape, said right circular conical trapezoidal concave being formed concentrically and surrounding said right circular conical surface, and wherein said crushing room is provided with an inclination guide member having an inclination surface at an angle between 10' and 70' with respect to an axis direction of said crushing room, in a rear portion thereof, thereby to form an upward flow path or a downward flow path.

In accordance with the collision type supersonic jet crusher according to the third invention, the crusher has the actions and the effects described in the first invention and the second invention, in combination. As a result, there is an effect that the processing ability of the crusher is further improved.

Further objects and advantages of the present invention will be apparent from the following description of the preferred embodiments of the invention as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a longitudinal sectional view show ing a main portion of a first embodiment according to the present invention.

Fig. 2 is a perspective view of a circular member in the first embodiment as shown in Fig. 1.

Fig. 3 is a perspective view of a crushing collision member in the first embodiment as shown in Fig. 1.

Fig. 4 is a longitudinal sectional view showing a main portion of a second embodiment according to the present invention.

Fig. 5 is a perspective view of a division body in the second embodiment as shown in Fig. 4.

Fig. 6 is a longitudinal sectional view showing a main portion of a third embodiment according to the present invention.

Fig. 7 is a longitudinal sectional view showing a crushing equipment of prior examples.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described hereinafter referring to embodiments as shown in figures.

A first embodiment A general construction of a first embodiment of the crusher according to the present invention is similar to the crushing equipment shown in Fig. 7. Fig. 1 shows its main portion. In the first embodiment, as shown in Fig. 2, an annular member 2 having a right circular conical trapezoidal concave portion 1 is inserted into a cylindrical crushing room 37. The annular member 2 contacts to an inner circumferential surface of the crushing room 37 at a circumferential surface thereof, and contacts to a front edge surface of the crushing room 37 at a bottom surface thereof.

In Fig. 1, 3 denotes a penetrating hole through which a supersonic jet flow is injected, and the same reference numerals as shown in Fig. 7 indicate components identical with those shown in Fig, 7.

A solid angle (strictly speaking. a virtual solid angle) of the right circular conical trapezoidal concave portion 1 of the annular member 2 is set to the same solid angle 8 as a crushing collision member 40 as shown in Fig. 3. That is, in Figs. 1 and 3, an apex angle 9 of a longitudinal sectional shape (an isosceles triangle) of the right circular cone 38 ranges between 30 and 150'. and a (virtual) apex angle of the right circular conical trapezoidal concave portion 1 equals to the apex angle 8 mentioned above.

An assembly of the right circular cone 38 and the disk 39 is adapted to be divided and furtherdetachably mounted on the collision member 40 by a jig of an exclusive use. Thereby only the disk which has been abraded can be easily exchanged, and the disk can be easily upside down.

The right circular cone 38 and the disk 39 may be identical in material with each other, and may be different in material from each other.

That is, a combination of the material of the right circular cone 38 and the material of the disk can be selected freely. Accordingly, a proper material can be selected for each of a smashing face of the right circular cone 38 and a smashing face of the disk 39, and a melt article by heat can be prevented from generating and also a smashing efficiency can be improved. For example, the right circular cone 38 is made of ceramic having a coefficient of thermal conductivity not less than 0. 1 Cal/cm.sec. C at 20' C test, for example SiC and the like in such a manner that a leading end of the cone 38 does not receive an influence of'heat reserve of frictional heat due to the collision of the material to be crushed Ta thereto.The disk 39 is made of ceramic having an abrading characteristic not greater than o. 4g of a blasting abrading amount at an aluminum powder injecting angle 30', a pressure 5.5Kg/cm2 and 2 minutes injecting test, for example Si3N4 or SiC.

Further, due to the above mentioned construction, a shape of the leading end of the cone 38 can be exchanged easily. For example, it is preferable that the leading end of the cone 38 is shaped in smooth arch relating to a conical surface of the cone 38 at a range between 80 to 99% of a height H of the cone 38. According to the shape of the leading end of the cone 38, the heat reserve in the leading end of the cone 38 due to the frictional heat by the collision is prevented from concentrating in one point of the leading end of the cone 38. Therefore, when smashing a material of a low softening degree, a melt material by heat is prevented from generating. Incidentally, an application of such a shape to the leading end of the cone 38 brings the same advantage to the conventional one body type conical collision plate.

A second embodiment A general construction of a second embodiment of the crusher according to the present invention is similar to that of Fig. 7. Fig. 4 shows its main portion. In the second embodiment, a rear portion of the crushing collision member 40 is designated as a cylindrical portion 40a. The cylindrical portion 40a is inserted and supported between two detachable and unitable division bodies 11 and 12 as shown in Fig. 5. The division bodies 11 and 12, and the cylindrical portion 40a is inserted in the crushing room 37.

The division bodies 11 and 12 comprise right triangle prism congruent to each other, each of which has a bottom surface of a right triangle.

Concave portions 13 and 14 in a form of a semicircle are defined at the bottom surfaces on their one sides of the right triangle poles. The concave portions 13 and 14 are opposed to each other.

An inclination angle P of an inclination surface on a front side is set between 10' and 70'. An inclination guide member 21 comprising the division bodies 11 and 12 is arranged in the rear portion of the crushing room 37. Thereby, an upward stream path of a supersonic jet flow is formed by the inclination guide member 21.

A third embodiment A general construction of a third embodimen-t of the crusher according to the present invention is similar to Fig. 7. Fig. 6 shows its main portion. In the third embodiment, the circular member 2 as shown in Fig. 2, the division bodies 11 and 12, that is, the inclination guide member 21, as shown in Fig. 5 are provided. The third embodiment has respective effects and actions of the first and second embodiments in combination.

Thereby, a crushing ability of the crusher according to the third embodiment is extremely advantageous.

In the first and third embodiments, a portion of an inner surface of the crushing room 37 corresponding to the right circular conical trapezoidal concave portion 1 of the circular member 2 may be formed previously in one unit body with the crushing room 37. Furthermore, in the second and third embodiments, the inclination guide member 21 may be formed previously in one unit body with the crushing room 37, into which a rear portion of the crushing collision member 40 may be inserted.

A crushing experiment example performed by a crusher according to the present invention and a comparison experiment example performed by a prior crusher as shown in Fig. 7 will be described here inafter.

A first experiment example A polyester system resin of 15 weight parts, a styrene acryl system resin of 85 weight parts and a phthalocyanine system pigment of 5 weight parts were mixed (a softening point of 75 'C) with each other. It was melted and kneaded by a thermal roll mill and then cooled. After that, It was crushed roughly by a jaw crusher and then was crushed by the crusher as shown in Fig. 1. The crushed material of 83 kg per one hour could be supplied, in order to obtain a micro powder having a volume average particle diameter of 12 atom. In the first experiment example, the crusher having a crushing pressure of 6. 0 kg/cm2 and a maximum consumption air of 10 m3/minute was used.

In the first embodiment, the crushing collision member 40 was made of conventional ceramic, wherein, in which the apex angle 8 of the right circular cone 38 was 60', and in which an area ratio of a bottom area of the right circular cone 38 to an area of a circular plate (an annular collision surface) 39 was 1/2. The annular member 2 made of a ceramic was used. An interval d between a circular conical surface of the right circular cone 38 and a concave surface of the annular member 2 was set to 40 mm (refer to Fig.

1) A first comparison example The same crushed material as the first experiment example was crushed by the crusher as shown in Fig. 7. The crushed material of 80 kg per one hour could be supplied, in order to obtain a micro powder having a volume average particle diameter of 12 atom. In the first comparison example, the crusher having a crushing pressure of 6. 0 kg/cm2 and a maximum consumption air of 10 m3/minute was used similarly to the first experiment example.

A second experiment example The same crushed material as the first experiment example was crushed by the crusher as shown in Fig. 4. The crushed material of 81 kg per one hour could be supplied, in order to obtain a micro powder having a volume average particle diameter of 12- te m. In the second experiment example, the crusher having a crushing pressure of 6. 0 kg/cm2 and a maximum consumption air of 10 m3/minute was used similarly to the first experiment example.

Furthermore, the inclination guide member 21 made of the ceramic having an inclination angle P of 45' was used.

A third experiment example The same crushed material as the first experiment example was crushed by the crusher as shown in Fig. 6. The crushed material of 85 kg per one hour could be supplied, in order to obtain a micro powder having a volume average particle diameter of 12 Atom. In the third experiment example, the crusher having a crushing pressure of 6. 0 kg/cm2 and a maximum consumption air of 10 m3/minute was used similarly to the first experiment example.

Furthermore, the same circular member 2 as the first experiment example was used, and the same inclination guide member 21 as the second experiment example was used.

Results of the experiment examples and comparison examples mentioned above will be shown in total at the table 1.

Table 1 Air Coarse Supplied Consumption Particle Amount of Flow Amount Diameter Crushed Material First Experiment 10 m3/min 12 Atm m 83 kg/hr Example First Comparison 10 m3/min 12 m 80 kg/hr Example Second Experiment 10 m3/min 12 Atm m 81 kg/hr Example Third Experiment 10 m3/min 12 m 85 kg/hr Example From the table 1, it is known that the crush ing abilities of the crushers in the first. second and third experiment examples are superior to that in the first comparison example, and that the crushing ability of the crusher in the third experiment example is superior to both of the first experiment example and the second experiment example.

Many widely different embodiments of the present invention may be constructed without departing from the spirit and scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments described in the specification, except as defined in the appended claims.

Claims (7)

CLAIMS:

1. A collision type supersonic jet crusher comprising: a crushing chamber; a supersonic jet flow path communicated with said crushing chamber for injecting into said crushing chamber said material to be crushed; a crushing collision member disposed in said crushing chamber concentrically with and opposite to said nozzle, said crushing collision member having a right circular conical surface for dispersing a supersonic jet flow of sand material from said supersonic jet flow path, and an annular collision surface as a primary collision surface lying concentrically on a bottom edge portion of said right circular conical surface; said crushing chamber being adapted to constitute at an inner surface thereof a secondary collision surface of said material;; wherein said crushing chamber is provided with, at a front portion thereof, a right circular conical trapezoidal concave surface having the same solid angle as said right circular conical surface of said crushing collision member and having an apex angle between 300 and 1500 with respect to a longitudinal sectional shape, said right circular conical trapezoidal concave surface being formed concentrically and surrounding said right circular conical surface.

2. A collision type supersonic jet crusher according to Claim 1, wherein the right circular conical trapezoidal concave surface is formed by inserting an annular member forming said circular conical trapezoidal concave portion into said crushing chamber.

3. A collision type supersonic jet crusher comprising: a crushing chamber; a supersonic jet flow path communicated with said crushing chamber for injecting into said crushing room said material to be crushed; a crushing collision member disposed in said crushing chamber concentrically with and opposite to said nozzle, said crushing collision member having a right circular conical surface for dispersing a supersonic jet flow of said material from said supersonic jet flow path, and an annular collision surface as a primary collision surface lying concentrically on a bottom edge portion of said right circular conical surface; said crushing chamber being adapted to constitute at an inner surface thereof a secondary collision surface of said material;; wherein said crushing chamber is provided with an inclined guide member having an inclined surface at an angle between 100 and 700 with respect to the axis of the crushing chamber, in a rear portion thereof, thereby to form an upward flow path or a downward flow path.

4. A collision type supersonic jet crusher according to Claim 3, wherein said inclined guide member is formed by two detachable and unstable division bodies, and a rear portion of said crushing collision member is inserted and supported between said two division bodies.

5. A collision type supersonic jet crusher comprising: a crushing chamber; a supersonic jet flow path communicated with said crushing room for injecting into said crushing room said material to be crushed; a crushing collision member disposed in said crushing chamber concentrically with and opposite to said nozzle, said crushing collision member having a right circular conical surface for dispersing a supersonic jet flow of said material from said supersonic jet flow path, and an annular collision surface as a primary collision surface lying concentrically on a bottom edge portion of said right circular conical surface, said crushing chamber being adapted to constitute at an inner surface thereof a secondary collision surface of said material, wherein said crushing chamber is provided with, at a front portion thereof, a right circular conical trapezoidal concave surface having the same solid angle as said right circular conical surface of said crushing collision member and having an apex angle between 300C and 1500 with respect to a longitudinal sectional shape, said right circular conical trapezoidal concave being formed concentrically and surrounding said right circular conical surface, and wherein said crushing chamber is provided with an inclined guide member having an inclined surface at an angle between 100 and 700 respect to the axis of the crushing chamber, in a rear portion thereof, thereby to form an upward flow path or a downward flow path.

6. A collision type supersonic jet crusher according to Claim 5, wherein the right circular conical trapezoidal concave surface is formed by inserting an annular member forming said right circular conical trapezoidal concave portion into said crushing chamber.

7. A collision type supersonic jet crusher according to Claim 5 or Claim 6, wherein said inclined guide member is formed by two detachable and unstable division bodies, and a rear portion of said crushing collision member is inserted and supported between said two division bodies.