JPH05338798A - Rotary feeder - Google Patents

Abstract

PURPOSE:To finely adjust the space between a rotor blade and a casing inner wall. CONSTITUTION:In a casing 1 having an upper opening 2 and a lower opening 3, a shaft 4 to which a plurality of rotor blades 5 are radially fixed is supported in such a manner as to be capable of rising and lowering, and the space between the rotor blades 5 and the casing 1 inner wall is adjusted by the rising and lowering of the shaft 4 to provide the optimum space between the rotor blade 5 and the casing 1 inner wall.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary feeder used for transporting powder or granular material such as plastic pellets, and more particularly to gas due to a pressure difference between an inlet and an outlet of the powder or granular material of the rotary feeder. The present invention relates to a rotary feeder that can efficiently supply a fixed amount of powder and granules to a transport pipe with a minimum amount of leakage.

[0002]

Background of the Invention and Prior Art and Problems Thereof A rotary feeder has a rotor 51 which is rotatably supported in a casing 55 having upper and lower openings as shown in FIG.
Since a plurality of blades 52, 52, ... Are radially fixed to the rotary feeder, the granular material A is fed from the hopper 50 disposed above the rotary feeder to another tank or the granular material transport device. Widely used for quantitative supply. The granular material A is the upper hopper 50 as described above.
Is guided to the rotor blades 52 by gravity drop from the bottom, and is supplied from the lower outlet to the transport pipe 54 connected to the air supply source 56 by the rotation of the rotor 51, but the upper and lower parts of the rotary feeder are pressurized inside the transport pipe 54. Due to the pressure difference, the rotor blades 52, 52, ... And the casing 55
Gas leaks to the low pressure side from the gap with the inner wall. When the pressure difference becomes large, the amount of gas leaked to the upper part of the rotary feeder also increases, which impedes the fall of the powder or granules A and reduces the amount of powder or granules charged into the rotary feeder. There is a possibility that the granules will not fall and the granules cannot be transported stably.

Therefore, in order to minimize the amount of gas leakage due to the above-mentioned pressure difference, the rotor blades 52, 52 ,.
.. and the inner wall of the casing 55 must be minimized. However, in order to reduce the gap, it is necessary to manufacture the rotor blades 52, 52, ... And the casing 55 with a considerably high precision, and the manufacturing cost thereof is very high. Further, if the above gap is made too small, the rotor blade may thermally expand depending on the temperature condition of the powder or granular material, or if the casing is deformed by applying a force to the casing from the outside, the rotor blade may be deformed by the inner wall of the casing. There is a risk that it will come into contact with the rotor and become unrotatable, or that the rotor blade will be worn or damaged.

Therefore, in order to block the amount of gas leakage due to the above-mentioned pressure difference, two rotary feeders are installed to increase the ventilation resistance to reduce the amount of gas leakage, or the rotor blade is made of synthetic resin. Alternatively, a member made of a durable elastic body is attached to the tip of the rotor blade to rotate the rotor blade while sliding it into contact with the casing to prevent gas leakage. However, in the former case, the effect of reducing the amount of gas leakage is small and the equipment cost is high, and in the latter case, the rotation of the rotor blade causes the tip of the rotor blade to wear due to sliding contact with the inner wall of the casing, There is a risk that abrasion powder and debris due to the abrasion will be mixed in the powder or granular material to be transported, and there is also a troublesome problem such as replacement of members.

On the other hand, Japanese Patent Publication No. 3-75461 discloses an invention of a rotary feeder for pneumatic transportation. In the rotary feeder according to this publication, the rotor is eccentrically rotatable with respect to the rotating shaft, so that the pressurization is performed. The pressure of the generated air pushes the rotor upward, and the rotor blade rotates while contacting the inner wall near the upper opening of the casing, so that the leakage of high-pressure air is blocked and the granular material is transported.

However, although the contact area between the rotor blade and the casing is extremely small, the surface pressure received by the differential pressure acts as an excessive force. Therefore, in the above invention, the tip portion of the rotor blade is made of a hard material. The surface of the casing is hardened or the inner wall of the casing is hard-coated to prevent wear. However, the above-mentioned padding of the rotor blade tip and the hard coating of the inner wall of the casing have limitations, and the differential pressure increases as the transport pressure to the granules increases, increasing the wear resistance of the hard material. Excessive excess contact pressure may occur and the rotor blades may not rotate smoothly, and in some cases the rotor blades and casing may be damaged, and the wear pieces and broken powder may be mixed with the granular material.

On the other hand, the means for transporting the powder or granular material by the rotary feeder is currently widely used because it has a simple mechanism and is easy to operate as compared with other transport means.
In order to increase efficiency and improve productivity, even in order to increase transport pressure more than ever, there has been a long-felt need for a technique that quickly solves the problems of the conventional rotary feeder described above.

[0008]

SUMMARY OF THE INVENTION A rotary feeder has a structure in which a powder or granular material supplied from a raw material tank or the like to a hopper is dropped onto a rotor on which a plurality of rotor blades are fixed in a radial direction to rotate the rotor blades. The gas to be pressurized from the lower air supply source is dropped into a transport pipe through which the powder particles are efficiently pumped in the transport pipe. When the gap between the casing and the inner wall of the casing is large, the pressurized gas in the transport pipe flows away from the tip of the rotor blade toward the hopper,
The pressure in the transport pipe is reduced, which leads to a decrease in the efficiency of pumping the powder and granules in the transport pipe, and the upward flow of gas in the hopper causes the powder and granules to flow backward, reducing the amount of powder and granules input. Will be done.

Therefore, it is important how to minimize the gap between the rotor blade and the inner wall of the casing. Therefore, the present invention solves the above-mentioned problems of the prior art, the mechanism of the device is simple, the manufacturing cost is low, and the rotor blade is smoothly rotated while the leakage of the high pressure gas is blocked as much as possible, and the granular material is The purpose of the present invention is to provide a rotary feeder capable of quickly and efficiently transporting.

[0010]

In order to achieve the above-mentioned object, a rotary feeder according to the present invention lifts or lowers a shaft having a plurality of rotor blades fixed radially in a casing having an upper opening and a lower opening. It is characterized in that it is supported as much as possible and the gap between the rotor blade and the inner wall of the casing is adjusted by raising and lowering the shaft.

[0011]

A rotary feeder according to the present invention supports a shaft having a plurality of rotor blades fixed in a radial direction in a casing having an upper opening and a lower opening so that the shaft can be vertically moved up and down. Since the gap is adjusted by raising and lowering the axis in the vertical direction, the gap can be minimized without contact between the rotor blade and the inner wall of the casing. Is what you can do.

[0012]

Embodiments of the present invention will be described with reference to the drawings.
Is a cylindrical casing having an upper opening 2 and a lower opening 3, 4 is a shaft on which a plurality of rotor blades 5 are fixed in a radial direction, and the shaft 4 is the rotor blade in the casing 1 described above. 5 and the inner wall of the casing 1 are arranged so as to have a predetermined minute gap. Further, a drive source 6 for rotating the shaft 4 is provided at a rear end portion of the shaft 4 via a flexible joint 7 connected to the shaft 4, and the presence of the flexible joint 7 causes the shaft 4 to move. Even if it moves up and down a little, it can sufficiently follow the movement in the up and down direction. 8 is a hopper connected to the upper opening 2 of the casing 1 described above, and 9
Is a transportation pipe that communicates with the lower opening 3 of the casing 1, and an air supply source (not shown) is connected to the rear portion of the transportation pipe 9 to supply high-pressure air into the transportation pipe 9.

The structure for supporting the shaft 4 in the casing 1 will be described. At the tip side of the shaft 4,
At one end of the casing 1, a side cover 11 having a hole through which the shaft 4 can be inserted is fixed in the center, and a disc-shaped cover 13 is fixed to the outer periphery of the annular side cover 11. The upper part and the lower part are attached via a gasket 14 to a substantially annular sub-casing 12 having a horizontal shape. Reference numeral 16 denotes a bearing which is disposed on the tip end side of the shaft 4 and rotatably supports the shaft 4. Reference numeral 17 denotes a bearing housing in which the bearing 16 is mounted.
Is supported by adjusting bolts 18 and 18 'which are screwed onto the horizontal portion of the sub-casing 12 above and below. 19 is the lower adjustment bolt 1 described above.
It is a dial gauge that connects to 8 '.

Numerals 20 and 20 'are rectangular parallelepiped guides fixed to the outer side of the side cover 11 fixed to the end of the casing 1 so as to come into contact with both side surfaces of the bearing housing 17 described above. The shaft 4 is rotatably supported by a bearing 16, and the bearing housing 17 in which the bearing 16 is mounted is fixed to the side cover 11 as described above.
Since it is interviewed with 20 ', the guide 20,
It is possible to move vertically up and down along 20 'and adjust bolt 1
By finely adjusting 8, 18 ', the shaft 4 can be moved up and down by a small amount in the vertical direction.

Next, the structure for supporting the rear end side of the shaft 4 will be described. A side cover 21 having a hole through which the shaft 4 can be inserted is fixedly provided at the other end of the casing 1. A substantially annular sub-casing 22 in which an upper part and a part of the lower part are horizontal is fixedly provided on the outer peripheral side of the sub-casing 22, and an annular cover 23 is provided outside the sub-casing 22. It is fixed via a gasket 24 having an opening formed in the center. Reference numeral 23a denotes an inner cover fixed to the outer end of the bearing housing 27 via the gasket 24. Since the gasket 24 is made of an elastic material, the shaft 4 is prevented from moving in the vertical direction. Can be followed sufficiently. Reference numerals 32 and 32 'are adjusting bolts screwed into the horizontal portion of the sub-casing 22 to support the bearing housing 27 from above and below, and 33 is a dial gauge connected to the adjusting bolt 32.

Reference numeral 26 denotes a bearing which is attached to a bearing housing 27 and rotatably supports the shaft 4. The central portion of the bearing housing 27 has projections 28, 28 'which are horizontal in opposite directions to the shaft 4. Is projected. On the other hand, the side cover 21 fixed to the casing 1
Inside the rectangular parallelepiped guide members 29, 29 ′ fixed to the outside of the shaft, recesses 30, 30 ′ are formed in the horizontal direction with respect to the shaft 4, respectively, and the protrusions protruding from the bearing housing 27 are provided. 28, 28 'are loosely fitted in the recesses 30, 30' of the guide members 29, 29 '.

Therefore, the shaft 4 is rotatably supported by the bearing 26, and the projections 28, 28 'projectingly provided on the bearing housing 27 are bored in the rectangular parallelepiped guides 29, 29' fixedly mounted on the side cover 21. Since the recesses 30 and 30 'are loosely fitted, the shaft 4 does not move in the horizontal direction and can be moved up and down along the guides 29 and 29' only in the vertical direction. 'Is operated to move the shaft 4 up and down through the bearing housing 27, whereby the gap between the rotor blade 5 and the inner wall of the casing can be adjusted. In the figure, 31 and 31 are O-rings arranged on the inner peripheral surface of the bearing housing 27.

Since the present embodiment is configured as described above, its operation will be described. To describe the operation, powder particles are introduced from the hopper 8 to rotate the rotor blades 5 and the pressurized gas is fed under pressure to the transport pipe 9. Then, the casing 1 having the upper opening 2 and the lower opening 3 is sealed by the covers 13 and 23, 23a having the gaskets 14 and 24 attached to both sides thereof, so that there is no escape of the pressurized gas. In addition, since the gap between the rotor blade 5 and the inner wall of the casing 1 is minimized, gas leakage is also minimized, and the granular material is efficiently pumped, but the amount of the granular material to be transported, It is necessary to adjust the gap between the rotor blade 5 and the inner wall of the casing 1 by the temperature and the transport pressure so that the gap satisfies the above conditions.

The above-mentioned rotor blade 5 and casing 1
When it becomes necessary to adjust the gap between the inner wall of the rotor and the inner wall of the bearing, in the present embodiment, of the two bearings 16 and 26 for supporting the shaft 4 on which the rotor blade 5 is fixed at its front end and rear end. Bearing housing 17 for holding the tip bearing 16
Is prevented from moving in the horizontal direction, and guides 20 and 20 ′ that can be moved up and down only in the vertical direction are fixedly installed facing the side cover 11, and a bearing 26 that supports the rear end of the shaft 4 is provided.
The bearing housing 27 that holds the projections 28, 28 'projecting in the horizontal direction of the shaft 4 respectively,
The guide member 29, 29 ′ fixed to the guide member 29, 29 ′ is provided with the recessed portion 30, 30 ′ formed in the guide member 29, 29 ′.
Since the shafts 8 and 28 'are loosely fitted, the shaft 4 does not move in the horizontal direction and can be moved up and down only in the vertical direction. Therefore, the adjustment bolt 1 screwed onto the sub-casings 12 and 22 at the upper part of the shaft 4.
8 ', 32' are loosened, a gap is provided between the tips of the adjusting bolts 18 ', 32' and the bearing housings 17 and 27, and then screwed into the sub-casings 12, 22 at the lower part of the shaft 4 for adjustment. Rotate the bolts 18 and 32 by finely adjusting them and pulling them up to a predetermined level while maintaining the balance of the shaft, and then finely adjusting the adjusting bolts 18 'and 32' on the upper part of the shaft 4 to fix the shaft level. It is possible to make the gap between the blade 5 and the inner wall of the casing 1 to a minimum value of 3 to 100 mm.

The clearance between the rotor blade and the inner wall of the casing, the operation of the adjusting bolt, the rotation speed of the shaft, the charged amount of the powder, and the gas pressure to be pumped are all optimally set by the computer depending on the transportation conditions of the powder. , Driven. Also,
In this embodiment, they are collectively referred to as powder particles, but, of course, their shapes such as powder, particles, and pellets are not limited, and the bearing housing and guide at the rear end of the shaft are In the above description, the fitting between the convex portion and the concave portion was described as the fitting mode, but the shape of the fitting portion is not limited, and in the present embodiment, the vertical movement of the shaft is adjusted by the adjusting bolt. Although the adjustment is made, the point is to move the shaft in the vertical direction and fix it at an arbitrary position while maintaining the balance of the shaft. For example, the shaft may be finely adjusted by a cam mechanism. It should be noted that clogging of the powder or granular material in the casing 1,
Measures such as bridge are mainly the shape of rotor blade,
It can be solved by the method such as the number of sheets and the angle when fixed to the shaft.

In the present embodiment, the shaft is supported at the front end and the rear end of the shaft, and when the shaft is moved up and down in the vertical direction, the shaft is not moved in the horizontal direction but is moved up and down only in the vertical direction. The shape of the guide used is changed in consideration of the elongation of the shaft in the longitudinal direction due to thermal expansion, so that the shaft can cope with some expansion at the tip portion.

According to the present embodiment, the rotary feeder for efficiently feeding the granular material by minimizing the gap between the rotor blade fixed to the shaft and the inner wall of the casing to prevent leakage of the pressurized gas as much as possible. The bearing housing, which holds the bearings that support the shaft, can be moved vertically in the vertical direction only along the guide without moving the bearing housing in the horizontal direction by the guide. It is possible to raise and lower the shaft in the vertical direction while maintaining the equilibrium level, and to minimize the gap between the rotor blade and the inner wall of the casing.

In order to minimize the gap between the rotor blade and the inner wall of the casing as described above, the roundness and dimensions of the components such as the casing cover, the rotor blade, and the shaft should be manufactured with high precision. If possible, but
There is a limit to the processing accuracy, and it also costs money, and considering the thermal expansion of each device due to the temperature of the powder or granules to be put in, the significance of manufacturing each device with high accuracy as described above is lost. Will end up. However, since the present embodiment is configured as described above, fine adjustment of the gap between the rotor blade and the inner wall of the casing becomes easy.

[0024]

The rotary feeder according to the present invention supports a shaft having a plurality of rotor blades fixed in a radial direction in a casing having an upper opening and a lower opening so that the shaft can be moved up and down.
Since the gap between the rotor blades and the inner wall of the casing is adjusted by raising and lowering the shaft, the gap between the rotor blades and the inner wall of the casing can be adjusted to a minimum, and the operation for the adjustment is simple. The structure is simple, the manufacturing cost is low, and the effect of this device on the industry is remarkable.

[Brief description of drawings]

FIG. 1 is an overall explanatory view of a rotary feeder of the present invention.

FIG. 2 is a sectional view taken along line BB of FIG.

FIG. 3 is a right side view with the cover of FIG. 1 removed.

4 is a left side view of FIG. 1 with the cover removed.

FIG. 5 is an explanatory diagram of a rotary feeder.

[Explanation of symbols]

 1 Casing 2 Upper opening 3 Lower opening 4 Rotor blade 8 Hopper 9 Transport pipe 11,21 Circular side cover 12,22 Sub-casing 13,23 Disk-shaped cover 16,26 Bearing 17,27 Bearing housing 18,18,32,32 'Adjustment bolts 20, 20, 29, 29' Guide member 28 Convex portion 30 Recessed portion

Claims (1)

[Claims] 1. A shaft having a plurality of rotor blades fixed in a radial direction is supported in a casing having an upper opening and a lower opening in a vertically movable manner, and a gap between the rotor blade and the inner wall of the casing is adjusted by lifting the shaft. A rotary feeder characterized by: