JPH0476888B2 - - Google Patents

Description

[Detailed description of the invention]

Industrial Application Fields This invention replaces the rotary leaf feeder, which could conventionally be used only in high-speed, low-concentration systems using a low-pressure air source such as a blower, by using a high-pressure air source such as a compressor to move powder and granules at low speed and high speed. The rotary feeder has a structure that allows for continuous and fixed concentration conveyance, and the rotating shaft of the rotor is eccentrically supported in a cylindrical casing, and the pin at the end of the shaft engages with the hole between the rotor shaft and the drive shaft. This invention relates to a rotary leaf feeder that can utilize higher-pressure air and realize continuous fixed-quantity supply transportation. Conventional technology In general, low-speed transportation in the pressure-feeding pneumatic transportation method of powder and granular materials means that the amount of transportation is small, the diameter of the transportation pipe is small, and the mass flow rate of the transportation air is approximately 2 to 12.
Kg/m ² · s. On the other hand, high-speed transportation refers to a pneumatic transportation method that uses a Roots blower or turbo blower with a discharge air pressure of less than 1 Kg/cm ² as the air source. Good, 12
Transport is performed at a mass flow rate exceeding Kg/m ² ·s, and is a low-concentration transport method mainly suitable for medium-distance transport. In the aforementioned low-speed transportation method, a compressor with a normal pressure of about 5 to 7 kg/ ^cm2 is commonly used as an air source.
As a storage supply source for powder and a delivery mechanism into a transport pipeline, it is essential to install a cellar-type or flank-type blow tank that is regulated as a pressure vessel. However, in the batch switching method, it is inevitable that the transport volume will fluctuate when switching batches.
In addition, as the level of stored powder and granular material changes within the same batch, the amount sent to the transportation pipeline changes, and as a ripple effect of fluctuations in the delivery section, plugs may be crushed within the transportation pipeline. , and that it is difficult to reform after crushing, and the resulting fluctuations in transportation volume cannot be prevented. On the other hand, the rotary feeder has a simple structure in which the rotor rotates within the casing, and it easily blocks the upper and lower passages outside the casing with the required pressure difference, allowing a fixed amount of powder to fall while maintaining airtightness. It is widely used for supplying or mixing powder and granules into transportation systems because it can be supplied in a fixed quantity as desired by adjusting the rotational speed of the rotor. The clearance between the casing and the rotor of a rotary feeder increases as the pressure difference between the top and bottom of the casing increases, so the amount of pressure gas leaking increases. Objects fall less or become uneven, making it difficult to supply a constant quantity. Therefore, even if it is a low-speed, high-concentration transportation method or a high-speed, low-concentration transportation method using a compressor as an air source, for example, in a long-distance, high-pressure transportation method where the pressure loss exceeds 1.5 kg/ ^cm2 , it is difficult to push high-pressure air. As mentioned above, a blow tank is an indispensable component in order to transport the material to be transported into the transport pipeline system. It was thought that it would be impossible to put into practical use a low-speed, high-concentration transport system incorporating the rotary feeder mechanism. In order to reduce the gap between the casing and the rotor, the rotor tip is coated with a soft resin to reduce rotational resistance, and a rotary leaf feeder is constructed with embedded carbon chips and protrudes outward using a spring. was proposed, but there were problems with wear resistance and reliability, and the rotary feeder was considered unsuitable for long-distance, high-pressure transportation. Problems to be Solved by the Invention Therefore, the inventors have made various improvements to the rotary leaf feeder itself, with the aim of realizing a transportation method using higher pressure air in the pneumatic transportation of powder and granular materials using the rotary leaf feeder. As a result of our investigation, we found that by eccentrically supporting the rotating shaft of the rotor in the casing, the rotor is pushed in response to the pressure difference between the inlet passage and the discharge passage.For example, when the discharge passage is under high pressure, Since the rotor moves to the inlet side and can rotate with close to zero clearance with the casing, leaks due to pressure differences are prevented, and powder and granular materials can be transported using air at a higher pressure than before. Knowledge of what can be done (Japanese Patent Application Laid-Open No. 63-160926
Publication No.). On the other hand, in order to improve the efficiency of pneumatic transport, it has recently become desirable to achieve higher transport pressures when transporting powdered and granular materials such as ultra-finely divided or surface-activated composite materials. Ta. An object of the present invention is to provide a rotary leaf feeder that can realize a transportation method using higher pressure air in pneumatic transportation of powder and granular materials. Means for Solving the Problems This invention has a rotor built into a cylindrical casing having upper and lower openings in the vertical direction, with a rotating shaft horizontally and eccentrically supported, and the blade tips of the rotor are connected to the inlet passage. In the rotary leaf feeder, which can come into contact with the inner circumferential surface of the casing near the inlet or outlet due to the pressure difference with the discharge side passage, the rotary A rotary leaf feeder characterized in that a plurality of freely pivotally supported pins are loosely fitted into the other pin holes to allow eccentricity between the rotor rotating shaft and the rotational drive shaft pivotally supported in the casing. The rotary feeder is further characterized in that the casing is provided with a communication path for introducing return side rotor chamber pressure to the rotor chamber filled with powder and granules. Function To be more specific, the rotary leaf feeder according to the present invention rotatably supports a plurality of pins on the end face of either one of the rotor shaft and the drive shaft, or on both end faces, and supports the pins on the end face of the other shaft or the drive shaft. The above-mentioned pin is loosely fitted into a pin hole provided in a disc interposed between the shaft end faces, and the pin is pivotally supported in a disc interposed between the shaft end faces, and the pin is inserted into the pin hole provided in both shaft end faces. The above-mentioned pin is loosely fitted to allow eccentricity between the rotor shaft and the drive shaft supported by the casing to enable torque transmission. When the inventors used this rotary leaf feeder in a pressure-feeding air transport device, the pressure-feeding air source was
Using a compressor that can produce compressed air of Kg/cm ² or more, we investigated the optimal application conditions and found that a configuration in which the rotor shaft is supported eccentrically was created by connecting the rotor shaft and drive shaft with a pin at the end of the shaft. By engaging the parts,
It is suitable for using higher pressure air, and the rotor chamber filled with powder in the casing is communicated with the return side rotor chamber on the opposite side of rotation, so that the return side rotor chamber pressure is filled with powder and granules. The present invention was completed based on the discovery that low-speed, high-density pneumatic transport could be achieved by introducing the air into the rotor chamber. Embodiment An embodiment of the present invention will be described below based on the drawings. FIGS. 1A and 1B and 2A and 2B are longitudinal sectional front explanatory views of the rotary feeder according to the present invention and layout diagrams showing the engagement relationship between pins and pin holes. Third
The figure is an explanatory longitudinal cross-sectional side view of the rotary feeder according to the present invention. In the rotary feeder according to the present invention, as shown in detail in FIG. The diameter is slightly smaller than the minor axis of the elliptical cross section. In the example shown in FIG. 1a, a plurality of pins 12 are rotatably installed at regular intervals on the outer circumferential side of the rotor shaft end face 11 on the right side in the figure, and these pins 12 are attached to a bearing on the right side of the casing 1 in the figure. Pins 12 provided at regular intervals on the outer circumferential side of the end surface of the rotary drive shaft 3
It is loosely fitted into a pin hole 4 having a diameter larger than the outer diameter of the pin hole 4. In addition, in the example shown in FIG. 2a, a plurality of pins 1 are provided at regular intervals on the outer peripheral side of the end surface of the drive shaft 3 which is supported by the rotor shaft end surface 11 and the bearing part 2 of the casing 1.
2 and 5 are rotatably installed, and these pins 12 and 5
is loosely fitted into a pin hole 21 having a diameter larger than the outer diameter of each pin 12, 5 provided at a constant interval on the outer circumferential side of a disc 20 rotatably disposed between each end face of the rotor shaft 10 and the drive shaft 3. . In both of the rotary feeders shown in Fig. 1 and Fig. 2, the rotor 10 has the above-mentioned eccentric configuration without having both ends of the rotary shaft supported. An example is shown in which the shafts are supported in contact with each other. When the pressure on the outlet side of the casing 1 is larger than the pressure on the inlet side of the casing 1 due to a reverse differential pressure, the rotor 10 is lifted from the bottom to the top, and the rotor 10 is lifted up from below to the upper circumferential inner surface of the casing 1 near the lower end of the inlet. It will rotate while being in close contact with. That is, at least two of the blade ends of the rotor 10 rotate as if sliding in direct contact with the circumferential inner surface of the casing 1 at all times with zero distance, but the number of blades of the rotor 10 is determined depending on the required number of blades. It is necessary to design and manufacture according to the specifications and dimensions of the rotary feeder. In addition, the casing 1 includes, as shown in FIG.
Communication holes 7 and 8 and a connecting pipe 9 are provided for providing a pipe line that communicates the rotor chamber filled with powder in the casing and the return rotor chamber on the opposite side of rotation, and the return side rotor chamber It is also preferable that the bar pressure is introduced into the rotor chamber filled with the granular material. This configuration greatly contributes to reducing the amount of leakage under reverse height differential pressure of the rotary leaf feeder. It has been demonstrated that the amount of leakage from the contact between the two is negligible despite the high differential pressure conditions. Furthermore, in order to prevent the communication pipe from being clogged with powder or granules, a pipe through which compressed air from a compressor can be introduced may be provided. Further, the blades of the rotor can be appropriately selected from so-called parallel type, helical type, W-helical type, etc. depending on the type of powder or granular material, and the number of blades can be similarly selected as appropriate for the purpose of continuous quantitative determination. The shape of the inlet can be appropriately selected depending on the type of powder or granular material, such as a full-face opening or an inclination with respect to the rotational axis of the rotor. Comparison of a pneumatic transport device using a rotary feeder according to the present invention, in which a chute tube is connected to the inlet, a drop tube is connected to the outlet, and a multiphase feed pipe is connected to the drop tube, and a conventional batch type pneumatic conveyor. did.
The comparison in Table 1 is for transporting nylon pellets with a diameter of 3 mm and a length of 3 mm for 150 m, and is expressed as an index with the apparatus using the rotary feeder according to the present invention being 1.

[Table] Effects of the Invention In the rotary leaf feeder according to the present invention, the rotor is installed eccentrically with respect to the housing. The rotor is pushed and rotates in a state in which it contacts or is about to contact the upper inlet side, that is, in a state in which the clearance at the tip of the rotor blade is close to zero, thereby preventing pressure leakage in this part. For example, when a chute tube is connected to the inlet of the rotary feeder according to the present invention and a drop tube is connected to the outlet, the effect of the material seal of the chute tube, the effect of stirring and mixing to assist quantitative discharge in the drop tube, and This, combined with the effect of forming appropriate plugs of a certain length and at certain intervals in the multiphase feed pipe connected to the drop tube, enables continuous quantitative supply transport with low-speed, high-concentration transport using a compressor as an air source. do. In addition, in the handling process of various new micronized materials and composite materials in recent years, particles are transferred at a low speed as much as possible to prevent particle breakage, deterioration, decrease in homogeneity, and contamination. There is a growing demand for a low-speed, high-concentration pneumatic transportation system that focuses on reducing the chance of frictional contact with walls, and this can more than meet this demand.

[Brief explanation of the drawing]

FIGS. 1A and 1B and 2A and 2B are longitudinal sectional front explanatory views of the rotary feeder according to the present invention and layout diagrams showing the engagement relationship between pins and pin holes. Third
The figure is an explanatory longitudinal cross-sectional side view of the rotary feeder according to the present invention. 1...Casing, 2...Bearing part, 3...Drive shaft,
4, 21... Pin hole, 5, 12... Pin, 6... Bolt, 7, 8... Communication hole, 9... Connection pipe line, 10... Rotor, 11... Rotor shaft end surface.

Claims (1)

[Claims] 1. A rotor is housed in a cylindrical casing having upper and lower openings in the vertical direction, with a rotating shaft horizontally and eccentrically supported, and the blade tips of the rotor are connected to an inflow side passage and a discharge side passage. In the rotary leaf feeder, which can come into contact with the inner circumferential surface of the casing near the inlet or outlet with a pressure difference of A rotary leaf feeder characterized in that a plurality of pins are loosely fitted into the other pin holes to allow eccentricity between the rotor rotating shaft and a rotational drive shaft pivotally supported in a casing. 2. The rotary leaf feeder according to claim 1, wherein the casing is provided with a communication path for introducing return side rotor chamber pressure to the rotor chamber filled with powder.