JP3803040B2 - Pneumatic feeder for pneumatic transportation - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is an air transporting powder feeder for transporting powder to a distance by discharging a predetermined amount of powder from a storage chamber and a silo above the storage chamber, and the high pressure air in the air transport pipe The present invention relates to a technique for preventing a decrease in powder feeding accuracy due to influence.
[0002]
[Prior art]
Conventionally, pneumatic transporting powder feeders that supply a predetermined amount of powder from a storage chamber to an air transport path have been provided with a rotating supply board around the bottom of the storage chamber so that the storage chamber and the outside of the storage chamber can be crotched. The rotating supply board is provided with a plurality of small chambers for storing the powder in the storage chamber, and the powder in the storage chamber is filled with the powder in the storage chamber and rotated to place the powder in the chamber outside the storage chamber in the air transport path. It is a structure in which the powder is discharged, flows into the downstream side together with air, and is conveyed away with air. However, when the pressure of air for pneumatic transportation increases in this conventional pneumatic transport powder feeder, air flows into the storage chamber of the powder feeder via the rotary feeder, and the powder movement is disturbed. There was a problem that accuracy deteriorated. The influence of this air was significant when the air pressure difference between the discharge part and the storage chamber exceeded 1.0 KPa.
In addition, an ejector is installed in the middle of the pneumatic transport section, and the ejector lowers the air pressure of the discharge section to generate a negative pressure, so that the negative pressure causes the powder to be sucked from the discharge section of the rotary feeding board. There is also a powder feeder that feeds powder into the tube. However, in this powder feeding device using negative pressure, if the suction force is weak, the discharge of the powder becomes weak and clogs, and if the suction force is strong, the powder and air leak directions are the same. There is a problem that the fluctuation of the powder becomes large and the powder feeding accuracy is poor.
[0003]
[Problems to be solved by the invention]
The problem to be solved by the present invention is to provide an air transporting powder feeder capable of solving the conventional problems, reducing the influence even when the air pressure is increased, and improving the powder feeding accuracy. Another object of the present invention is to provide an air transporting powder feeder capable of simultaneously using a plurality of air transport pipes having different low pressure and high pressure air pressure.
[0004]
[Means for Solving the Problems]
The configuration of the present invention that solves this problem is as follows.
1) A required amount of powder in the storage chamber is accommodated in a rotating supply board provided so that the storage chamber and the outside of the storage room are crotched, and the stored powder is transferred to the outside of the storage room by rotation of the rotary supply board. In an air transport type powder feeder that discharges powder to an outdoor air transport path, a nozzle for accelerating the air flow rate is installed in the air transport path slightly upstream of the discharge part where the rotary supply board discharges the powder. The powder discharge section is located at a distance from the acceleration air flow so that the air flow accelerated by the nozzle does not directly touch the rotating supply board, and the static air pressure at the discharge section is determined by the air pressure in the storage chamber. Pneumatic transporting powdering device characterized in that the effect of air pressure is reduced by reducing the air pressure difference between the discharge part and the storage chamber so as to be greatly reduced in a high range. 2) Rotating to the outer periphery of the air flow acceleration nozzle Auxiliary blowout that blows a small amount of air toward the discharge part of the supply panel 1) The pneumatic transporting powder feeding device 3) described above, wherein the discharge of the powder is ensured, and the pressure difference between the air pressure in the storage chamber and the powder discharging part is 1.0 KPa. The air transporting powder feeder 4) according to 1) or 2), wherein the air flow rate by the nozzle is adjusted as described below. In the air transporting powder feeder according to 1) to 3), the rotation is further performed in the storage chamber. A second rotary supply disk and a second discharge part having the same structure as the supply board / discharge part are provided, and a second air transport path without a nozzle for flowing an air flow is provided so as to be in contact with the second discharge part. Powder supply for pneumatic transportation, in which high-pressure compressed air is sent to the pneumatic transportation path to pneumatically transport powder, and low-pressure compressed air is sent to the second pneumatic transportation path without nozzles to pneumatically transport powder. In the device.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The main part of the present invention is that the air pressure (static pressure) of the discharge part where the rotary supply board of the powder feeder discharges the powder is greatly reduced by increasing the air flow velocity of air transportation by the nozzle, and the discharge The pressure difference between the air outlet and the air in the storage chamber is made lower in the range where the pressure in the discharge section is higher than the pressure in the storage chamber. In particular, if the differential pressure is within 1.0 KPa, the effect of air pressure can be greatly reduced.
The powder discharge unit is provided at a position slightly away from the accelerated air flow so that the air flow accelerated by the nozzle does not directly touch the rotating supply board.
Further, by providing the auxiliary blowing part, it is possible to spray a small amount of air toward the part of the supply board where the powder is accommodated at the position of the discharge part, and to ensure the discharge of the powder in the discharge part.
In the present invention, a single storage chamber is provided with a plurality of rotary supply panels, discharge sections, and air transportation paths, and even if there is a difference in the air pressure of each air transportation path, the differential pressure can be made substantially the same by the nozzle, This makes it possible to provide a plurality of independent powder air transport paths without being affected by each other.
[0006]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
In this embodiment, a high-pressure and low-pressure pneumatic transport path / powder supply mechanism is provided in one storage chamber, a nozzle is provided only in the high-pressure pneumatic transport path, and a rotary feeder disk of the high-pressure powder supply mechanism is provided. It is the example which provided the auxiliary blowing part which blows air toward a discharge part.
[0007]
FIG. 1 is an explanatory diagram of the embodiment.
FIG. 2 is a vertical cross-sectional view of a main part of the embodiment.
FIG. 3 is a plan view of a main part of the embodiment.
FIG. 4 is an explanatory diagram showing an air flow in the embodiment.
[0008]
In the figure, 1 is a storage chamber, 1a is a storage chamber bottom surface, 1b is a storage chamber side surface, 1c is a powder filling port that opens the rotary supply disk 2a portion of the storage chamber bottom surface 1a, and 1d is an agitation mounted in the storage chamber 1 The blade 1e is a motor for rotating the stirring blade, 2 is a powder supply mechanism provided at the bottom of the peripheral side of the storage chamber 1, 2a is a rotary supply plate of the powder supply mechanism, 2b is radially on the outer periphery of the rotary supply plate 2c is a small powder storage chamber formed between the blades, 2d is a motor drive unit for rotating the rotary supply board 2a, and 2e is for sealing a portion outside the storage chamber of the rotary supply board 2a. The casing 2f is a discharge part of the rotary supply board 2a provided in the casing 3 is an air transport path that takes in the high-pressure air of the blower 9, 4 is an air velocity acceleration nozzle 5 provided in the air transport path, Auxiliary blow-out section 5a for blowing out a small amount of air toward the discharge section 2f of the rotary supply board 2a The outlet pipe 5b is a branch pipe for introducing air into the outlet pipe from the air transport path 3, 5c is a detection hole for air pressure (powder pressure) near the discharge section 2f, and 6 is an air transport main pipe for powder transport. , 7 is a mixing unit for connecting the air transportation path 3 to the same air transportation main line, 8 is a compressor of a pre-high pressure air source to the air transportation pipe 3, 9 is a blower for sending air to the air transportation main line 6, and 10 is A powder silo above the storage chamber 1, 11 is a butterfly valve.
In the drawing, 12 is a low-pressure pneumatic transporting powder feed mechanism having the same structure as the powder feed mechanism 2 provided in the storage chamber 1, 12a is a low-pressure rotary feed board having the same structure as the rotary feed board 2a, and 12e is the same low pressure. Casing 12a, 12f is a low-pressure discharge part of low-pressure rotary supply board 12a, 13 is a low-pressure air transport passage in which the low-pressure discharge part is provided in the middle of the passage, 14 is a low-pressure air blower, and 15 is powder. It is a blowout nozzle.
[0009]
In this embodiment, the powder in the powder silo 10 moves to the storage chamber 1, and the powder in the storage chamber 1 is formed between the blades 2b on the outer periphery of the rotary supply board 2a while being stirred by the rotation of the stirring blade 1d. Between the small chambers 2c.
The rotary supply board 2a is rotated by a motor drive unit 2d, and the powder filled in the small chamber 2c is sent along with the rotation of the rotary supply board 2a, and is slid by the ceiling wall of the casing 2e to become a fixed amount. It is discharged at 2f.
[0010]
The high-pressure air 3 in the air transportation path is taken in by branching the high-pressure air generated by the blower 9 from the air transportation main pipeline 6. The air pressure is 30 KPa or more (gauge pressure), the nozzle 4 accelerates the flow velocity to 200 m / s or more, and the static pressure is about 3.0 KPa.
[0011]
At this time, a small amount of air is also blown from the blow pipe 5a of the auxiliary blow section 5 on the outer periphery of the nozzle 4, and the discharge section 2 of the rotary supply board 2a is blown to ensure discharge of the powder at the discharge section 2. .
[0012]
As a result, the discharge portion 2e has a positive differential pressure of about 1.0 KPa compared to the air pressure in the storage chamber, and the differential pressure is greatly reduced from about 10 KPa to 1.0 KPa when there is no nozzle, and a small positive pressure. Differential pressure was used. This positive differential pressure of about 1.0 KPa acts on the discharge part 2f and balances it with the powder pressure so that there is no flushing phenomenon, and a predetermined amount of powder is smoothly transported by air without being affected by air pressure or powder pressure. It feeds into the path 3 and is conveyed downward together with the air flow.
The air flow on the downstream side of the nozzle 4 that carries the powder in the air transport path 3 is reduced in flow rate to a pressure of about 10 KPa due to the increase in the area of the passage, and the powder and air are mixed through the mixing unit 7. It is sent to the air transport main pipeline 6 and sent to a distant powder blowing nozzle 15 together with powder and air from other supply devices.
Even when the compressor 8 is used as the air source of the high-pressure air transportation path, the static pressure of the discharge part 2f can be reduced by 20 KPa or more.
[0013]
In addition, the storage chamber 1 of the embodiment is provided with a powder feeding mechanism 12 for another low-pressure air transport path 13, and the low-pressure rotary supply board 12 a of the supply mechanism 12 is the same as the high-pressure side rotary supply board 2 a. The powder in the storage chamber 1 is filled and fed into the storage chamber 1 and discharged by the low pressure discharge section 12f. The low-pressure discharge part 12f is disposed in the low-pressure air transport path 13, and the powder is discharged and pneumatically transported by blowing off the air in the air transport path 13 directly. The differential pressure between the low pressure discharge section 12f and the air pressure in the storage chamber 1 and the differential pressure between the high pressure side discharge section 2f and the storage chamber 1 are approximately the same by the high pressure side nozzle 4. Even if the air pressure in the air transport path is different, a plurality of air transports are possible with high accuracy.
[0014]
【The invention's effect】
As described above, according to the present invention, by providing the nozzle for accelerating the flow velocity in the air transport path slightly upstream of the powder discharge section, the static air pressure of the discharge section is greatly reduced to be slightly higher than the air pressure in the storage chamber. By setting the pressure value (small differential pressure), the powder supply is not disturbed by the pressure of the transport air, and the powder supply accuracy is not lowered. In addition, the low-pressure and high-pressure air transportation paths can be used simultaneously.
By discharging a small amount of air from the auxiliary blowing portion toward the discharge portion on the outer periphery of the air jet flow of the nozzle, it becomes possible to reliably discharge the powder at the discharge portion.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of an embodiment.
FIG. 2 is a longitudinal sectional view of a main part of the embodiment.
FIG. 3 is a plan view of a main part of the embodiment.
FIG. 4 is an explanatory view showing an air flow of the embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Storage chamber 1a Storage chamber bottom surface 1b Storage chamber side surface 1c Powder filling port 1d Stirring blade 1e Motor 2 Powder supply mechanism 2a Rotation supply board 2b Blade 2c Small chamber 2d Motor drive part 2e Casing 2f Discharge part 3 Air transport path 4 Nozzle 5 Auxiliary Blowing section 5a Blowing pipe 5b Branch pipe 5c Detection hole 6 Pneumatic transport main line 7 Mixing section 8 Compressor 9 Blower 10 Powder silo 12 Powder supply mechanism 12a for low-pressure air transport Low-pressure rotary supply panel 12e Casing 12f Low-pressure discharge section 13 Low pressure Air transport path 14 Low pressure air blower 15 Powder blowing nozzle

Claims (4)

A rotating supply disc provided so that the storage chamber and the outside of the storage chamber can be crawled to store a required amount of powder in the storage chamber, and the powder stored by the rotation of the rotary supply disc is transferred to the outside of the storage chamber. In an air transport type powder feeder having a structure for discharging powder to an air transport path, a nozzle for accelerating air flow velocity is provided in the air transport path slightly upstream of the discharge section where the rotary supply board discharges powder. The body discharge unit is located at a distance from the acceleration air flow so that the air flow accelerated by the nozzle does not directly touch the rotating supply board, and the static air pressure at the discharge unit is higher than the air pressure in the storage chamber. A pneumatic feeder for reducing the influence of the air pressure by reducing the air pressure difference between the discharge part and the storage chamber so as to greatly reduce the air pressure. The air according to claim 1, wherein an auxiliary blow-out portion for blowing a small amount of air toward the discharge portion of the rotary supply board is provided on the outer periphery of the air flow acceleration nozzle so as to ensure discharge of the powder from the discharge portion. Transport powder feeder.   3. The air transporting powder feeding device according to claim 1, wherein the air flow rate by the nozzle is adjusted so that the pressure difference between the air pressure in the storage chamber and the discharge part of the powder is 1.0 KPa or less.   4. The pneumatic transporting powder feeding device according to claim 1, wherein the storage chamber is further provided with a second rotating supply disk and a second discharging part having the same structure as the rotating supply disk / discharge part, and in contact with the second discharging part. A second air transport path without a nozzle for flowing an air flow is provided, and high pressure compressed air is sent to the air transport path with the nozzle to pneumatically transport the powder, and the second air transport path without the nozzle is Pneumatic feeding powder feeder that sends low-pressure compressed air to pneumatically transport powder.

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