JPH0443708B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides an airflow type pulverization section for pulverizing a processed material from a raw material feeder using an air flow, and a processing material from the pulverization section into fine powder and coarse powder particles. The present invention relates to a crushing and classifying device that is provided with a classifying section and a conveying means for returning and supplying coarse powder from the classifying section to the crushing section.

[Conventional technology]

Conventionally, the conveying means was configured to be, for example, a dead weight drop type so that the entire amount of coarse powder particles from the classification section was immediately supplied to the airflow crushing section [for example, in JP-A-57
-Refer to Publication No. 135052].

[Problems to be solved by the invention] However, if the object to be processed is something that is difficult to crush, such as metal, the amount of coarse particles from the classification section tends to increase, and a large amount of coarse particles are If the reduced coarse particles are immediately supplied to the crushing section, the reduced coarse powder particles that are difficult to crush will rapidly increase, which will greatly reduce the crushing efficiency due to airflow in the crushing section, and will easily cause clogging in the airflow type crushing section, making it even more difficult. There was room for improvement.

The purpose of the present invention is to automatically and reliably prevent coarse powder particles from the classification section from being excessively supplied to the pneumatic crushing section, and to prevent operation from becoming impossible due to an increase in the amount of reduced coarse powder particles. The goal is to automatically and reliably prevent this from happening.

[Means for solving problems]

The characteristic configuration of the present invention is that the conveying means for returning the coarse powder from the classification section to the pneumatic crushing section for processing together with the material to be processed from the raw material feeder includes a retention section for the coarse powder and a coarse powder in the retention section. Measuring means for measuring particle size;
Further, a discharge means is provided to take out an excess amount of coarse powder particles to the outside of the system, and the amount of material to be processed supplied by the raw material feeder and the amount taken out by the discharge means are adjusted so as to maintain the measured value by the measuring means within a set range. The purpose of this invention is to provide a controller that automatically adjusts the temperature, and its functions and effects are as follows.

[Effect]

In other words, the coarse powder particles from the classification section are temporarily retained in the retention section and then supplied to the airflow type crushing section in appropriate amounts by the conveying means, so even if the amount of coarse particles from the classification section increases, the airflow type Excess reduced coarse powder particles are not supplied to the crushing section, and efficient crushing processing in the air flow crushing section can be reliably continued.

In addition, the amount of coarse particles in the retention area is detected by a measuring means,
If the detected amount exceeds the set amount and it becomes impossible to continue good operation due to the increase in the amount of coarse particles, the amount of material to be processed by the raw material feeder is reduced and the invention of coarse particles occurs. At the same time, since the excess amount of coarse particles can be taken out of the system by the discharge means, it is possible to reliably prevent troubles such as inability to operate due to an increase in the amount of coarse particles.

Furthermore, the amount of coarse particles in the retention section can be automatically maintained within the set range through the cooperation of the measuring means, controller, raw material feeder, and discharge means, which prevents operation failure due to an increase in the amount of coarse particles. This can be achieved reliably and effectively in terms of management.

〔Effect of the invention〕

As a result, even for materials that are difficult to crush with air flow crushing, such as metals, it is possible to reliably continue efficient crushing over a long period of time. It has now become possible to provide a crushing and classifying device that is even better in terms of overall performance.

〔Example〕

Next, an example will be shown with reference to FIGS. 1 and 2.

To form the pneumatic crushing section A, an annular collision surface 1
The ring 1 forming the a is automatically freely attached to the casing 2.
The material to be processed from the raw material feeder 3 is collided with the collision surface 1 by high-speed airflow from the pressure gas jetting nozzle 4a.
A nozzle 4 configured to blow the object toward a direction a is provided, and the object to be processed is pulverized by applying impact force by high-speed airflow and impact force by impact surface 1a.

As shown in FIG. 2, the nozzle 4 is arranged with respect to the collision surface 1a so that the object to be treated that bounces off the collision surface 1a revolves around the annular passage 5 around the ring 1, and the object to be treated is placed in the center (P ) It is configured so that it can be rotated around the area.

The ring 1 is sequentially rotated at a slow speed by a drive device,
Uneven wear of the ring 1 due to the object to be treated is prevented.

A cyclone type classification section B is provided below the crushing section A to separate the material to be processed falling from the crushing section A into fine powder and coarse particles. An upward fine powder discharge passage 8 formed by a cylindrical body 7 whose vertical position can be freely adjusted is connected to the center of the classification chamber 6, and a conical part is connected to the bottom of the classification chamber 6. The body 9 forms an annular coarse powder discharge passage 10.

In other words, the material to be treated falling from the annular passage 5 is separated into fine powder and coarse powder in the classification chamber 6 by inertial flow, the fine powder is sent to the fine powder discharge passage 8 by air current conveyance, and the coarse powder is reduced to coarse powder by falling under its own weight. The grains are configured to be sent to a grain discharge path 10.

The airflow chamber 11 is applied to the entire outer circumference of the classification chamber 6.
The swirling airflow chamber 11 is connected to the entire circumference of the annular coarse powder discharge passage 10, and the gas that swirls in the swirling airflow chamber 11 as it is ejected from the air supply pipe 12 is in an inertial swirling flow state. The coarse powder is configured to be supplied into the classification chamber 6 from the coarse powder discharge path 10.

That is, the swirling air current blows up the fine powder in the coarse powder particles and sends it to the fine powder discharge path 8, and the fine powder can be transported by air current.

A fine powder collector 13 and an exhaust fan 14 are connected to the fine powder discharge path 8, and the fine powder transported by the airflow is transferred to the fine powder collector 1.
3, it is configured so that it can be separated and recovered from the gas.

A conveyance means C is provided to return and supply the coarse powder particles from the classification section B to the crushing section A, and to form the conveyance means C, a retention section 15 for coarse powder particles connected to the coarse particle discharge path 10 is formed. A hopper 16 is provided in the upper part separately from the casing 3, and a load cell 17 for measuring the amount of coarse particles in the retention section 15 is provided at the support part of the hopper 16, and pressurization from the air supply path 18 is provided. Air flow conveying means 18 and 19 are separately formed and connected to the bottom of the hopper 16 for supplying the coarse powder that falls quantitatively from the hopper 16 with gas to the crushing section A through the pipe line 19. , a screw conveyor 20 is provided to take out an excess of coarse powder in the retention section 15 to the outside of the system, and a conical valve body 21 is provided to adjust the amount of coarse powder supplied from the hopper 16 to the air flow conveying means 18 and 19. It is provided. A sealing material 22a or 2 made of rubber, resin, cloth, etc. is installed between the casing 2 and the hopper 16, and between the hopper 16 and the air flow conveying means 18, 19, respectively.
2b is provided to prevent coarse powder particles from leaking out while enabling load detection by the load cell 17.

Based on the information from the load cell 17, the transmission section 3a of the raw material feeder 3 is operated to automatically start/stop the electric motor (M) of the screw conveyor 20, and the valve (V ₁ ) is provided with a microcomputer type controller 23 for automatically opening and closing operations, and is configured so that the amount of coarse powder in the retention section 15 is automatically adjusted as follows.

(b) When the measured weight (W) of the load cell 17 is less than the set lower limit value (W ₁ ) at the start of operation.

The speed of the raw material feeder 3 is controlled so that the material to be processed is supplied to the pulverizing section A at the maximum set amount, which is set to allow efficient processing according to the processing capacity of the pulverizing section A, and the valve (V ₁ ) is closed to control the air flow. conveyance means 18,
19 is stopped, the screw conveyor 20 is stopped, and the coarse powder is retained in the retention section 15.

(b) When the measured weight (W) is greater than or equal to the set lower limit value (W ₁ ) and less than the set upper limit value (W ₂ ).

The valve (V ₁ ) is opened to quantitatively reduce and supply the coarse powder to the crushing section A, and the coarse powder is re-pulverized, and the screw conveyor 20 is kept stopped.
Then, the rate of change in the measured weight (dw/dt) is detected, and the detected measured weight is determined based on the pre-programmed correlation between the rate of change in the measured weight (dw/dt) and the amount of supplied material (dQ/dt). Change (dw/
The speed of the raw material feeder 3 is controlled so that the amount of supplied material to be processed (dQ/dt) is commensurate with dt). In other words, when the rate of change in measured weight (dw/dt) increases, the rate of change (dw/dt) increases, the feed rate of the processed material (dQ/dt) decreases, and conversely,
When the rate of change in measured weight (dw/dt) decreases, the greater the rate of change, the greater the feed rate of the material to be treated (dQ/dt). At the same time, the amount of processing in the crushing section A is increased as much as possible to perform the crushing process efficiently.

(c) When the measured weight (W) exceeds the set upper limit (W ₂ ). The valve (V ₁ ) is kept open, and the speed of the raw material feeder 3 is controlled so that the material to be processed is supplied to the pulverizing section A at the minimum supply amount set so as not to significantly reduce the pulverizing efficiency, and the screw conveyor 20 to reduce the amount of coarse particles in the retention section 15 to below the set upper limit.

(d) When the measured weight (W) decreases below the set lower limit value (W ₁ ).

The valve (V ₁ ) is kept open, the screw conveyor 20 is kept in a stopped state, and as in the case of item (b) above, the amount of material to be processed (supplied) corresponding to the measured weight change (dw/dt) is The raw material feeder 3 is adjusted so that the ratio is dQ/dt), and the grinding process is carried out efficiently while the amount of coarse powder in the retention section 15 changes.

In short, the supply amount of the raw material feeder 3 and the screw conveyor 20 are adjusted so that the measured value by the load cell 17 is maintained within the set range (W<W ₂ ).
The amount taken out is automatically adjusted by a controller 23.

[Another example]

Next, another embodiment will be described.

The specific configuration of the pneumatic crushing section A can be changed as appropriate, and for example, the following configuration can be used.

(a) The ring 1 is formed into a polygonal shape, or formed so that it can be rotated intermittently by driving force or artificial force. Further, instead of the ring 1, a fixed member is used to form the collision surface 1a.

(b) A plurality of nozzles 4 may be provided, or a dedicated nozzle for reducing coarse powder particles may be provided.

(c) The annular passage 5 is omitted.

The specific configuration of the classification section B can be changed as appropriate, and for example, the following configuration can be used.

(a) A screen and a rotatable classification impeller are installed at the entrance of the fine powder discharge path 8.

(b) A second classifier is added between the classification chamber 6 and the fine powder collector 13 to enable two-stage classification or multi-stage classification. (c) The classification chamber 6 is placed above or to the side of the crushing section A. It is configured such that the material to be processed is sent from the crushing section A to the classification chamber 6 by an appropriate transport means such as an air flow transport pipe.

The conveying means C for reducing and supplying coarse powder particles can be appropriately modified in its system and specific configuration, and for example, the following configuration can be used.

(b) Use appropriate conveyors such as belt conveyors, bucket conveyors, screw conveyors, etc. singly or in combination.

(b) Adjust the vertical position of the valve body 21 using an air cylinder.
The valve body 21 may be configured to be operated by a suitable drive device such as a hydraulic cylinder or an electric motor, or by manual operation, or the valve body 21 may be fixed.

(c) Instead of the load cell 17, an optical means for detecting the level of the stored coarse particles or other suitable means for measuring the amount of coarse particles can be used, and these are collectively referred to as the measuring means 17.

(d) Instead of the screw conveyor 20, it is possible to use an appropriate means for taking out coarse particles, such as an air flow conveying pipe 24 with a valve (V ₂ ) shown in FIG. collectively. Further, the coarse powder particles may be returned and supplied to the raw material feeder 6 by the discharge means 20 and 24.

The operation mode of the raw material feeder 3 and the discharge means 20, 24 by the controller 23 can be changed appropriately, and for example, the following can be used.

(a) It is free to use the measured value by the measuring means 17, and the measured value itself, the differential value or integral value of a change in the measured value, etc. can be used.

(b) The amount of material to be processed supplied by the raw material feeder 3 can be adjusted by two-stage switching between maximum and minimum supply, multiple-stage switching, on/off control, appropriately programmed proportional control, or any other suitable method.

(c) Adjustment of the amount taken out by the discharge means 20, 24 is performed by closing the valve (V ₂ ) Open or
The amount taken out during operation of the discharge means 20, 24 can be adjusted by two-stage switching, multi-stage switching, appropriately programmed proportional control, or any other suitable method.

(d) How to combine the adjustment of the amount of material to be processed supplied by the raw material feeder 3 and the amount taken out by the discharge means 20, 24 can be appropriately selected. It may be programmed so that the first one is executed preferentially, and the other one is executed when the measured value by the measuring means 17 cannot be maintained within the set range.

(E) If the frequency at which the measurement location by the measurement means 17 exceeds the set upper limit exceeds the set value, the discharge means 20 and 24 are operated to take out all or most of the coarse particles in the retention section 15 out of the system. You can program it as follows.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIG. 2 is a view taken along the - arrow in FIG. FIG. 3 is a sectional view showing another embodiment of the present invention. A...Crushing section, B...Classifying section, C...Transporting means, 3...Raw material feeder, 15...Retention section, 1
7... Measuring means, 20, 24... Discharging means, 23
...Controller.

Claims (1)

[Claims] 1 An air-flow crushing section A that crushes the material to be processed from the raw material feeder 3 with airflow, a classification section B that separates the material from the pulverizing section A into fine powder and coarse powder, and a classification section B that separates the material from the classification section B into coarse powder. A pulverizing and classifying device is provided with a conveying means C for reducing and supplying powder particles to the pulverizing section A,
The conveyance means C includes a retention section 15 for coarse powder particles, a measuring means 17 for measuring the amount of coarse powder particles in the retention section 15, and a discharge means 2 for taking out an excess amount of coarse powder particles out of the system.
0 and 24, and the amount of material to be processed fed by the raw material feeder 3 and the discharge means 2 are adjusted so that the measured value by the measuring means 17 is maintained within a set range.
A crushing and classifying device equipped with a controller 23 that automatically adjusts the amount of 0 and 24 taken out.