JP2013250036A - Drying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drying device capable of reducing a size.SOLUTION: Moisture is removed from powders and granules by hot air supplied from a hot air supply line 6 into a drying hopper 3, and thereby, the powders and granules are dried. At this time, the air discharged from the inside of the drying hopper 3 to an exhaust line 12 flows through the exhaust line 12 toward a filter 13, and passes through the filter 13. A removing object contained in the air is removed by the filter 13. The powders and granules are supplied with the air into the drying hopper 3. At this time, the air discharged from the inside of the drying hopper 3 to the exhaust line 12 flows through the exhaust line 12 toward the filter 13, and passes through the filter 13. A removing object contained in the air is removed by the filter 13. Thus, one filter 13 is shared for removing the removing objects from air both at the time of drying the powders and granules and at the time of supplying the powders and granules to the drying hopper 3.

Description

  The present invention relates to a drying apparatus for drying a granular material.

  Prior to being supplied to the molding machine, the granular material that is the material of the resin molded product is subjected to a drying process for removing moisture.

  The drying apparatus for this drying process is provided with a hopper that accommodates powder particles. One end and the other end of the air circulation line are connected to the hopper. A blower, a heater, and a filter are interposed in the middle of the air circulation line. When the blower is driven, air flows through the air circulation line from the blower to the hopper. The air flowing through the air circulation line is heated while passing through the heater and becomes warm air. The hot air is supplied from the air circulation line into the hopper, passes through the hopper, and flows out from the hopper to the air circulation line. The hot air passing through the hopper removes moisture from the powder and the powder is dried. The air flowing through the air circulation line is returned to the blower after dust or the like mixed in the air is removed by the filter.

  One end of the primary transportation line is connected to the hopper. The other end of the primary transport line is connected to a material tank in which powder particles are stored. Furthermore, one end of an exhaust line is connected to the hopper. The other end of the exhaust line is open to the atmosphere. An ejector is interposed in the middle of the primary transportation line. When the ejector is driven, the pressure in the primary transport line becomes negative, and the powder is sucked from the material tank to the primary transport line. This granular material is carried into the hopper by air flowing through the primary transport line. And air and a granular material are isolate | separated in a hopper, a granular material is stored in a hopper, and air is discharged | emitted through an exhaust line. A filter is interposed in the middle of the exhaust line, and dust or the like mixed in the air flowing through the exhaust line is removed by this filter.

JP 2004-66529 A Japanese Utility Model Publication No. 63-125512 JP-A-62-147282

  As described above, the air circulation line, the primary transport line, and the exhaust line are connected to the hopper, and an intervening material such as a filter is interposed in each of these lines. Therefore, the conventional drying apparatus has a problem that the configuration is complicated and the size is large.

  In order to simplify the configuration, a configuration in which a part of the air circulation line and a part of the exhaust line are shared by one common line has been proposed. However, it is necessary to additionally provide parts such as a switching valve for switching the connection between the common line, the air circulation line, and the exhaust line, and the size has not been reduced.

  An object of the present invention is to provide a drying apparatus that can be reduced in size.

  In order to achieve the above object, a drying apparatus according to the present invention includes a container for storing a granular material, a filter for removing a removal target contained in a fluid, and a filter case for storing the filter. A dry fluid supply line for supplying a fluid after passing through the filter as a dry fluid into the container, and an upstream end, the upstream end and the downstream end opposite to the upstream end being connected to the filter case and the container, respectively When the dry fluid is supplied into the container from the dry fluid supply line, the fluid discharged from the container is directed to the filter. A dry discharge line that circulates in the same manner, and an upstream end and a downstream end opposite to the upstream end are connected to the container and the filter case, respectively. The transport discharge line through which the fluid discharged from the container circulates toward the filter and the fluid flowing through the transport discharge line are removed from the transport discharge line when supplied into the container together with the fluid. And a fluid exclusion line.

  The granular material to be dried is accommodated in a container. The container is connected to the downstream end of the drying fluid supply line, the upstream end of the drying discharge line, and the upstream end of the transportation discharging line. The upstream end of the drying fluid supply line, the downstream end of the drying discharge line, and the downstream end of the transportation discharging line are connected to a filter case containing a filter.

  In the container, the fluid after passing through the filter is supplied as a drying fluid through a drying fluid supply line. The dry fluid supplied into the container removes moisture from the powder and dries the powder. At this time, the fluid is discharged from the container to the discharge line during drying. The fluid discharged to the drying discharge line flows toward the filter through the drying discharge line and passes through the filter. The removal object such as dust contained in the fluid is removed by the filter.

  Moreover, a granular material is supplied with a fluid in a container. At this time, the fluid is discharged from the container to the discharge line during transportation. The fluid discharged to the transportation discharge line flows toward the filter through the transportation discharge line and passes through the filter. The removal object such as dust contained in the fluid is removed by the filter. The fluid flowing through the transport discharge line is removed from the transport discharge line through the fluid discharge line.

  Thus, one filter is shared by the removal of the removal target from the fluid flowing through the discharge line during drying and the removal of the removal target from the fluid flowing through the discharge line during transportation. Therefore, the size can be reduced as compared with a configuration in which a filter is provided for each application.

  It is preferable that a single common line is shared as the drying discharge line and the transportation discharge line. As a result, the configuration can be simplified and the size can be further reduced.

  The fluid exclusion line may be configured to release fluid to the atmosphere. The drying device may further include a valve that opens and closes the fluid exclusion line.

  The valve is preferably closed when the internal pressure of the fluid exclusion line is less than a predetermined pressure and opened when the internal pressure is equal to or higher than the predetermined pressure. As a result, when the granular material is supplied into the container together with the fluid without controlling the opening and closing of the valve, the excess amount of the fluid in the container, the discharge line during transportation, and the fluid exclusion line is automatically removed to the atmosphere. Can be released.

  Moreover, it is preferable that the upstream end of the fluid exclusion line is connected to the filter case. Thereby, the fluid which distribute | circulates the discharge line at the time of transport can be let through a filter, and the removal target object contained in the fluid excluded from the discharge line at the time of transport can be removed. Therefore, when the fluid exclusion line is configured to release the fluid to the atmosphere, the fluid after the removal target is removed can be released to the atmosphere.

  According to the present invention, one filter is commonly used for the removal of the removal target from the fluid flowing through the discharge line during drying and the removal of the removal target from the fluid flowing through the discharge line during transportation. Therefore, the size can be reduced as compared with a configuration in which a filter is provided for each application.

FIG. 1 is a diagram schematically showing the configuration of a drying apparatus according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram schematically showing the configuration of a drying apparatus according to an embodiment of the present invention.

  The drying device 1 is an on-machine type drying device that is disposed above the molding machine 2 and that dries the granular material supplied to the molding machine 2.

  The drying device 1 is provided with a drying hopper 3 that accommodates the granular material to be dried. The upper part of the drying hopper 3 has a cylindrical shape, and the lower part of the drying hopper 3 has a funnel shape that tapers downward. A lower end portion of the drying hopper 3 is connected to the molding machine 2.

  At the lower end of the drying hopper 3, an opening (not shown) for supplying the granular material in the drying hopper 3 to the molding machine 2 is formed. This opening may be provided with a valve for switching supply and stop of the powder from the drying hopper 3 to the molding machine 2.

  The drying hopper 3 is provided with a hot air supply pipe 4. The upper end portion of the hot air supply pipe 4 penetrates the upper lid 5 that closes the upper surface of the drying hopper 3 and protrudes above the upper lid 5, for example. The lower end portion of the hot air supply pipe 4 is disposed on the central axis of the drying hopper 3 in the lower part in the drying hopper 3 and has a conical shape extending downward.

  One end of the hot air supply line 6 is connected to the upper end of the hot air supply pipe 4. A blower 7 is interposed in the middle of the hot air supply line 6. In addition, a heater 8 is interposed between the hot air supply line 4 and the blower 7 in the hot air supply line 6.

  One end of a primary transport line 9 is connected to the upper lid 5 of the drying hopper 3. The other end of the primary transport line 9 is connected to a raw material tank 10 in which powder particles are stored. An ejector 11 is interposed in the middle of the primary transport line 9.

  One end of an exhaust line 12 is connected to the upper lid 5 of the drying hopper 3. The other end of the exhaust line 12 is connected to a filter case 14 that houses a filter 13.

  The filter 13 is disposed in contact with the upper inner surface of the filter case 14. A first connection port 15 is formed at a portion of the filter case 14 where the filter 13 is in contact. The other end of the exhaust line 12 is connected to the first connection port 15. In the filter case 14, a space 16 is formed around the filter 13. The filter case 14 is formed with a second connection port 17 and a third connection port 18 facing the space 16. The other end of the hot air supply line 6 is connected to the second connection port 17.

  One end of an air discharge line 19 is connected to the third connection port 18. A pressure adjustment valve 20 is provided at the other end of the air discharge line 19. The pressure regulating valve 20 is closed when the internal pressure of the air discharge line 19 is less than a predetermined pressure, and is opened when the internal pressure of the air discharge line 19 is equal to or higher than the predetermined pressure.

  When the granular material stored in the drying hopper 3 is dried, the blower 7 is driven. Thereby, air is sent out from the blower 7, and the air flows toward the drying hopper 3 through the hot air supply line 6.

  Further, the heater 8 is turned on. The air flowing through the hot air supply line 6 is heated while passing through the heater 8 to become hot air, and is supplied from the hot air supply line 6 into the drying hopper 3. The heater 8 is PID controlled so that the temperature of the hot air flowing through the hot air supply line 6 becomes a predetermined temperature. By supplying warm air into the dry hopper 3, moisture contained in the granular material in the dry hopper 3 is vaporized. Air containing moisture in the drying hopper 3 is discharged from the drying hopper 3 to the exhaust line 12. The air flowing through the exhaust line 12 flows into the filter case 14 from the first connection port 15 of the filter case 14, passes through the filter 13, and reaches the space 16 in the filter case 14. When the air passes through the filter 13, a removal target such as dust mixed in the air is captured by the filter 13 and removed.

  By driving the blower 7, the air in the space 16 is sucked into the hot air supply line 6 through the second connection port 17. Then, the air is sucked into the blower 7 and sent out from the blower 7 toward the drying hopper 3.

  Thereby, air circulates through the warm air supply line 6, the drying hopper 3, the exhaust line 12, and the filter case 14 in this order. As a result, the granular material in the dry hopper 3 is dried.

  When powder particles are supplied to the drying hopper 3, compressed air from a compressor (not shown) is supplied to the ejector 11. By supplying this compressed air, an air flow flowing from the raw material tank 10 toward the drying hopper 3 is generated in the primary transport line 9. And the granular material stored in the raw material tank 10 is sucked into the primary transport line 9 by the airflow, and the granular material is transported by the airflow toward the primary transport line 9 toward the drying hopper 3. The Then, the granular material supplied into the dry hopper 3 is separated from the air and stored in the dry hopper 3.

  The blower 7 is driven while the granular material is supplied to the drying hopper 3, and air circulates through the hot air supply line 6, the drying hopper 3, the exhaust line 12, and the filter case 14. Since air is supplied from the primary transport line 9 to the drying hopper 3, the internal pressures of the hot air supply line 6, the drying hopper 3, the exhaust line 12, and the filter case 14 increase accordingly. Accordingly, when the internal pressure of the air discharge line 19 becomes equal to or higher than a predetermined pressure, the pressure regulating valve 20 is automatically opened. And if the internal pressure of the air discharge line 19 falls below predetermined pressure, the pressure regulation valve 20 will close automatically. Thereby, the internal pressure of the warm air supply line 6, the drying hopper 3, the exhaust line 12, and the filter case 14 is maintained below a predetermined pressure.

  The drying device 1 is provided with a level sensor 21 that detects that the level of the granular material stored in the drying hopper 3 has reached a predetermined level. When the level sensor 21 detects that the level of the granular material stored in the drying hopper 3 has reached a predetermined level, the supply of compressed air from the compressor to the ejector 11 is stopped, and the drying hopper 3 is stopped. The supply of powder and granule is stopped.

  Note that the PID control of the heater 8 may be continued while the granular material is supplied to the drying hopper 3. When it is difficult to maintain (temperature control) the temperature of the hot air flowing through the hot air supply line 6 at a predetermined temperature, the PID control of the heater 8 is interrupted and the heater 8 is kept at a constant duty ratio. The heater 8 may be controlled with relatively low accuracy such as being turned on / off. However, it is preferable that the heat generation from the heater 8 is continued, thereby preventing the temperature of the air circulating through the hot air supply line 6, the drying hopper 3, the exhaust line 12 and the filter case 14 from being excessively lowered.

  As described above, the particles to be dried are accommodated in the drying hopper 3. The drying hopper 3 is connected to the downstream end of the hot air supply line 6 and the upstream end of the exhaust line 12. The upstream end of the hot air supply line 6 and the downstream end of the exhaust line 12 are connected to a filter case 14 that houses a filter 13.

  In the drying hopper 3, the air after passing through the filter 13 is supplied as hot air as dry air through the hot air supply line 6. The warm air supplied into the drying hopper 3 removes moisture from the powder and dries the powder. At this time, air is discharged from the drying hopper 3 to the exhaust line 12. The air discharged to the exhaust line 12 flows through the exhaust line 12 toward the filter 13 and passes through the filter 13. The removal target contained in the air is removed by the filter 13.

  In the dry hopper 3, powder particles are supplied together with air. At this time, air is discharged from the drying hopper 3 to the exhaust line 12. The air discharged to the exhaust line 12 flows through the exhaust line 12 toward the filter 13 and passes through the filter 13. The removal target contained in the air is removed by the filter 13.

  Thus, one filter 13 is shared by the removal of the object to be removed from the air both when the granular material is dried and when the granular material is supplied to the drying hopper 3. Therefore, in the drying apparatus 1, the size can be reduced as compared with the configuration in which a filter is provided for each application.

  A single exhaust line 12 is commonly used as a line through which air discharged from the drying hopper 3 circulates during drying of the granular material and a line through which air discharged from the drying hopper 3 circulates during transportation of the granular material. . As a result, the configuration can be simplified and the size can be further reduced.

  The upstream end of the air discharge line 19 is connected to the third connection port 18 of the filter case 14. Thereby, by passing through the filter 13, the air from which the removal target is removed can be released to the atmosphere through the air release line 19.

  Further, the air discharge line 19 is provided with a pressure regulating valve 20, which closes when the internal pressure of the air discharge line 19 is less than a predetermined pressure, and the internal pressure is equal to or higher than the predetermined pressure. Sometimes open. Thereby, when the granular material is supplied into the drying hopper 3 together with air without performing valve opening / closing control, on the circulation path composed of the hot air supply line 6, the drying hopper 3, the exhaust line 12 and the filter case 14. The excess of air at can be automatically released to the atmosphere.

  As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, although the pressure adjustment valve 20 is provided in the air discharge line 19, an electromagnetic valve may be provided in the air discharge line 19 instead of the pressure adjustment valve 20. In this case, the opening and closing of the solenoid valve is controlled by the control unit including the microcomputer, and the solenoid valve is opened in response to the start of the supply of compressed air from the compressor to the ejector 11. The solenoid valve may be closed in response to the stop.

  Further, the case where the fluid flowing through the hot air supply line 6, the primary transport line 9, the exhaust line 12 and the air discharge line 19 is air is taken as an example. However, the fluid flowing through the hot air supply line 6, the primary transport line 9, the exhaust line 12, and the air discharge line 19 is not limited to air, but may be, for example, nitrogen gas or the like to prevent oxidation of the granular material. An inert gas may be used. Furthermore, other types of gas, for example, carbon dioxide (carbon dioxide) may be used, or a mixed gas in which a plurality of types of gases such as nitrogen gas and carbon dioxide are mixed may be used.

  Further, in the above-described embodiment, the on-machine type drying apparatus 1 for drying the granular material supplied to the molding machine 2 is taken up. However, the drying apparatus according to the present invention is supplied to the molding machine 2. It may be an apparatus for drying granular materials other than granular materials, for example, granular foods and medicines.

  In addition, various design changes can be made to the above-described configuration within the scope of the matters described in the claims.

1 Drying device 3 Drying hopper (container)
6 Hot air supply line (dry fluid supply line)
12 Exhaust line (drying line during drying, discharging line during transportation)
13 Filter 19 Air release line (fluid exclusion line)
20 Pressure control valve

Claims (5)

A container for containing the powder,
A filter for removing an object contained in the fluid;
A filter case for housing the filter;
A dry fluid supply line for supplying an upstream end and a downstream end opposite thereto to the filter case and the container, respectively, and supplying the fluid after passing through the filter as a dry fluid into the container;
An upstream end and a downstream end opposite to the upstream end are connected to the container and the filter case, respectively, and when the drying fluid is supplied into the container from the drying fluid supply line, the fluid discharged from the container is the filter. A dry discharge line that circulates towards
The upstream end and the downstream end opposite to the upstream end are connected to the container and the filter case, respectively, and when the granular material is supplied into the container together with the fluid, the fluid discharged from the container is directed toward the filter. A distribution line for transportation,
A drying apparatus comprising: a fluid exclusion line for removing fluid flowing through the transport discharge line from the transport discharge line.   The drying apparatus according to claim 1, wherein a single common line is shared as the discharge line during drying and the discharge line during transportation. The fluid exclusion line is configured to discharge fluid to the atmosphere,
The drying apparatus according to claim 1, further comprising a valve that opens and closes the fluid exclusion line.   The drying device according to claim 3, wherein the valve is closed when an internal pressure of the fluid exclusion line is less than a predetermined pressure, and is opened when the internal pressure is equal to or higher than the predetermined pressure.   The drying device according to any one of claims 1 to 4, wherein the fluid exclusion line has an upstream end in a fluid flow direction connected to the filter case.

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