JPH0116539B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an air flow type crushing apparatus used for crushing objects having viscoelasticity at room temperature, such as synthetic resins or natural resins, at low temperatures.

PRIOR TECHNOLOGY A so-called low-temperature jet grinding device vaporizes liquid nitrogen, embrittles the material to be ground in a low-temperature atmosphere of the vaporized nitrogen gas, and pulverizes the material to be ground using a high-speed airflow of the vaporized nitrogen gas.
This is conventionally known as disclosed in Japanese Patent Application Laid-Open No. 48-90048.

However, in the case of such a product, the material to be crushed is cooled and made brittle by being brought into contact with the low-temperature atmosphere made of vaporized nitrogen gas only after it enters the crushing device. For this purpose, a separate vaporizer is required from the crushing device for converting liquid nitrogen into vaporized nitrogen gas, and in this vaporizer, the liquid nitrogen receives heat from the external environment and discards the cold energy that the liquid nitrogen had. Since vaporized nitrogen gas was generated by , the cooling energy inherent in liquid nitrogen was wasted without being used, and it was uneconomical in terms of heat.

Problems to be Solved by the Invention It is an object of the present invention to eliminate the drawbacks of the conventional low-temperature jet pulverizer as described above, and to provide a refrigerant chamber in which a gas flow for pulverizing the material to be pulverized is formed as a part of the pulverizer. The liquid refrigerant is generated through heat exchange with the material to be crushed in the storage section, and there is no need to install a separate vaporizer to generate a gas flow, making it compact overall and not wasting the cold energy of the refrigerant. We provide grinding equipment that can

Means for Solving the Problems In order to achieve the above-mentioned objects, the first aspect of the invention is to provide a refrigerant chamber surrounding a reservoir formed at the lower part of the crushing chamber, and to connect the refrigerant chamber with the crusher. It is characterized by communicating with a plurality of gas nozzles provided on the lower side wall of the chamber.

Next, the second invention provides a refrigerant chamber surrounding the storage section formed at the lower part of the grinding chamber, communicates the refrigerant chamber with a plurality of gas nozzles provided on the lower side wall of the grinding chamber, and further provides a storage section. This is characterized in that an auxiliary refrigerant chamber is provided which penetrates through the storage portion and communicates between the opposing refrigerant chambers.

Furthermore, the third invention provides a refrigerant chamber surrounding the storage section formed at the lower part of the grinding chamber, communicates the refrigerant chamber with a plurality of gas nozzles provided on the lower side wall of the grinding chamber, and further includes a storage section. A plurality of auxiliary gas nozzles opening at the bottom of the refrigerant chamber are provided, and the auxiliary gas nozzles and the gas chamber above the refrigerant chamber are connected through a conduit.

Function In the above-mentioned apparatus, the material to be crushed is fed into the cylindrical crushing chamber from the upper supply section, and the liquid refrigerant is fed into the refrigerant chamber. This liquid refrigerant is vaporized in the refrigerant chamber by receiving heat from the material to be crushed in the storage section that is transmitted through the crushing chamber wall of the storage section, and this low-temperature gas flow is ejected from the gas nozzle into the crushing chamber. The ejected low-temperature gas stream embrittles the objects to be crushed in the crushing chamber, and the high-speed airflow causes the objects to collide with each other to crush them.

In this case, in the second invention, by providing an auxiliary refrigerant chamber that penetrates the storage part, heat exchange between the refrigerant and the material to be crushed is performed more efficiently, and in the third invention, the bottom part of the storage part By spouting a low-temperature gas flow from the refrigerant chamber to the auxiliary gas nozzle provided in the auxiliary gas nozzle, the material to be crushed is prevented from solidifying on the wall surface of the crushing chamber.

Embodiment An embodiment of the invention shown in FIG. 1 will be described.

Reference numeral 1 indicates a cylindrical grinding chamber, in which a supply part 2 is attached to one side of the upper part, a storage part 3 is formed in the lower part of the supply part 2, and a plurality of gas nozzles 8 that open into the grinding chamber 1 are installed above it. ing.

A refrigerant chamber 4 is formed by a cold insulation wall 5 surrounding the storage section 3, and this refrigerant chamber 4 is divided into a lower liquid chamber 6 and an upper gas chamber 7. The gas chamber 7 and the gas nozzle 8 are communicated through a conduit 9, and the conduit 9 is equipped with an automatic on-off valve 10, and a liquid supply pipe 11 is opened in the liquid chamber 6. A control valve 12 is installed at 11.

An auxiliary refrigerant chamber 15 is provided passing through the storage section 3, and both ends thereof are open to the liquid chamber 6.

A plurality of auxiliary gas nozzles 16 are opened at the bottom of the storage section 3, and the gas chamber 7 and the gas nozzles 16 are communicated through a secondary conduit 17.
A pressure gauge 18 with contacts and a pressure regulating valve 19 are installed in this conduit 17 in this order from the gas chamber 7 side, and a branch pipe 20 is connected to the conduit 17 behind this pressure regulating valve 19. A valve 21 is installed and the tube 20 opens to the atmosphere.

In addition, safety valves 2 are installed at the upper and lower parts of the cold insulation wall 5 of the gas chamber 7.
2 and a liquid level detector 23 are installed respectively.

25 is a known airflow classifier installed in the upper chamber 18, and a high-speed rotating blade 27 is installed inside. An exhaust duct 26 is connected to this classification equipment 25, and an exhaust fan 28 is connected from the exhaust duct 26. Air is sucked in by the dust collector 29, and particulates contained in this air are collected by the dust collector 29. In this embodiment, the classifier 25 is built into the crushing chamber 1, but it can also be made independent from the crushing chamber 1.

When pulverizing is carried out using the above-mentioned apparatus, the material to be pulverized is fed into the pulverizing chamber 1 from the supply section 2, and a liquid refrigerant is fed into the refrigerant chamber 4 through the liquid supply pipe 11. This liquid refrigerant is vaporized by the heat that enters from the material to be crushed accumulated in the storage section 4 through the walls of the crushing chamber 1 and the auxiliary refrigerant chamber 15, and this vaporized gas is passed from the gas chamber 7 through the conduit 9 on the one hand. The gas is ejected from the gas nozzle 8 into the grinding chamber 1 as a gas stream.
Furthermore, the vaporized gas is ejected from the gas chamber 7 via the secondary conduit 17 and from the auxiliary gas nozzle 16 into the reservoir 3 as a gas stream. The ejected gas flow embrittles the objects to be crushed in the crushing chamber 1, and the high-speed airflow causes the objects to be crushed to collide with each other and are crushed. In this case, in particular, the gas flow from the auxiliary gas nozzle 16 also serves to crush the material to be crushed in the reservoir 3 and to prevent the material to be crushed from solidifying on the wall of the reservoir.

In the above case, since the refrigerant chamber 4 is surrounded by the cold insulation wall 5, heat intrusion from adjacent equipment, foundations, external environment, etc. is efficiently suppressed, and wasteful escape of cold heat held by the refrigerant is suppressed. .

The pulverized material thus pulverized is sent to the exhaust fan 2.
By operating 8, it flies through the grinding chamber 1,
Due to the impeller 27 of the airflow classifier 25 rotating at high speed, fine particles with a predetermined particle size or less are carried by the airflow, pass between the blades of the impeller 27, enter the dust collector 29 from the exhaust duct 36, and other particles are The coarse particles descend along the wall surface of the crushing chamber 1 and are crushed again in the storage section 3, and the process of crushing, ascending, sorting (classifying), and descending is repeated in this manner.

Next, the particles contained in the airflow that have entered the dust collector 29 are separated into airflow and particles, the particles are collected as a product, and the airflow is discharged to the atmosphere through the exhaust fan 28.

(1) In the above case, the amount of the material to be crushed is the standard value, that is, the fluid nozzle 8 of the crushing device
If the load is lower than the load that causes all of the refrigerant to operate, the amount of newly supplied material to be crushed is small, so the amount of heat received by the refrigerant decreases, and the amount of refrigerant vaporized decreases. As a result, the pressure of the vaporized gas decreases, and when it falls below the pressure value set in the pressure regulating valve 19, the contact pressure gauge 18 detects this and automatically opens/closes the valve 10 in stages according to the degree of pressure decrease. The gas nozzle 8 is closed and the number of operating gas nozzles 8 is reduced, thereby maintaining the pressure within the gas chamber 7 at a predetermined pressure.

In this case, when the amount of vaporized refrigerant decreases, the gas-liquid interface of the refrigerant in the refrigerant chamber 4 rises, but when the number of operating gas nozzles 8 decreases, the gas-liquid interface falls. However, in spite of this, in order to prevent the rise and fall of the gas-liquid interface to be too drastic, the level of the gas-liquid interface is detected by the liquid level detector 23, and the level of the gas-liquid interface is thereby detected. Control valve 12 is adjusted to maintain the proper level of air-liquid interface.

(2) When the amount of the material to be crushed is close to the standard value, the pressure gauge with contact 18 and the liquid level detector 23 will not output an abnormality detection signal, so the automatic on-off valve 10 and the control valve 12 will not be activated. The vaporized gas is maintained at a predetermined pressure simply by operating the pressure regulating valve 19 without any adjustment.

(3) If the supplied amount of the material to be crushed exceeds the standard value, or if the amount of heat brought in by it is abnormally large, or if the cold insulation wall 5 is damaged, etc. When the heat is abnormally large, the vaporization of the liquid refrigerant is accelerated, and the pressure in the gas chamber 7 becomes abnormally high despite the gas flow ejected from the gas nozzles 8 and 16. When the pressure cannot be adjusted only by operating the pressure regulating valve 19, the safety valve 22 operates to discharge the vaporized gas to the outside, thereby preventing damage to the device due to the pressure increase. .

Effects of the Invention The first invention is as described above, in which a refrigerant chamber is provided surrounding the reservoir formed at the lower part of the crushing chamber, and the refrigerant chamber and a plurality of gas nozzles provided on the lower side wall of the crushing chamber are connected to each other. Since the vaporized gas of the refrigerant that embrittles and crushes the material to be crushed obtains the heat for vaporizing it from the material to be crushed in the storage section, a separate There is no need to provide a vaporizer, making the whole system more compact, and the cooling energy of the refrigerant can be used effectively without wasting it.

The second invention is based on the first invention, and further includes an auxiliary refrigerant chamber that penetrates the storage part and communicates the opposing refrigerant chambers with the storage part in between. Exchanges are carried out more efficiently,
This has the effect of realizing more effective use of the cold energy of the refrigerant.

A third aspect of the present invention is that in the first aspect, a plurality of auxiliary gas nozzles opening at the bottom of the storage part are further provided, and the auxiliary gas nozzles and the gas chamber at the upper part of the refrigerant chamber are connected by a conduit, so that the pulverized material in the storage part is This has the effect of breaking up the objects, preventing the objects to be crushed from solidifying themselves, and also preventing the objects to be crushed from solidifying on the walls of the storage section, thereby facilitating the execution of effective crushing work.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view of an embodiment of the invention. 1... Grinding chamber, 2... Supply section, 3... Storage section,
4...Refrigerant chamber, 6...Liquid chamber, 7...Gas chamber, 8
... Gas nozzle, 9, 17 ... Conduit, 11 ... Liquid supply pipe, 15 ... Auxiliary refrigerant chamber.

Claims (1)

[Claims] 1. A plurality of gas nozzles are arranged on the lower side wall of a cylindrical crushing chamber having a supply section at the upper part, and a storage section for the material to be crushed is formed in the lower part of the crushing chamber. A pneumatic pulverizer that pulverizes objects to be pulverized by colliding with each other using a low-temperature gas flow ejected into a pulverizing chamber, characterized in that a refrigerant chamber surrounding the storage section is provided, and the refrigerant chamber and the gas nozzle are communicated with each other. Air flow type grinding equipment for low temperature grinding. 2. A plurality of gas nozzles are arranged on the lower side wall of a cylindrical crushing chamber having a supply section at the top, a storage section for the material to be crushed is formed further below the crushing chamber, and low-temperature gas is ejected from the gas nozzles into the crushing chamber. In a pneumatic pulverizer that pulverizes objects to be pulverized by colliding with each other using a gas flow, a refrigerant chamber surrounding the storage section is provided, the refrigerant chamber and the gas nozzle are communicated with each other, and the refrigerant chamber is connected to the storage section. An air flow type pulverizer for low-temperature pulverization, characterized in that an auxiliary refrigerant chamber is provided that communicates two refrigerant chambers facing each other. 3. A plurality of gas nozzles are arranged on the lower side wall of a cylindrical crushing chamber having a supply section at the top, a storage section for the material to be crushed is formed further below the crushing chamber, and low-temperature gas is ejected into the crushing chamber from the gas nozzles. In a pneumatic pulverizer that pulverizes objects to be pulverized by colliding with each other using a gas flow, a refrigerant chamber is provided surrounding the reservoir, the refrigerant chamber communicates with the gas nozzle, and the refrigerant chamber is opened at the bottom of the reservoir. A pneumatic pulverizer for low-temperature pulverization, characterized in that a plurality of auxiliary gas nozzles are provided, and the auxiliary gas nozzles and a gas chamber above the refrigerant chamber are connected through a conduit.