JPH0614153U - Rotary valve - Google Patents

Abstract

(57) [Summary] (Corrected) [Purpose] The purpose of the rotary valve that discharges granules quantitatively is to ensure smooth supply of granules and improve the function of preventing bites. [Configuration] Rotor (21) having a plurality of blades (23)
Is rotatably supported around the horizontal axis in the rotor case (25), and the shape of the blade (23) is V-shaped or curved to open rearward in the blade rotation direction.
In the granule inlet (28) provided in the upper part of (25), viewed from above,
Lower edge scraping edge that projects backwards in an inverted V shape
A baffle (30) having (30a) is provided. Further, in order to further improve the bite prevention function, the tip end portion in the radial direction of the blade (23) is formed in a tapered shape.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The invention according to the present application relates to a rotary valve for discharging granules such as plastic pellets in a fixed amount, and more particularly to a structure for preventing its entrapment.

[0002]

[Prior art]

 As shown in FIG. 6, the basic structure of this type of rotary valve is that a rotor 1 having a plurality of blades 3 radially is supported in a rotor case 5 so as to be rotatable around a horizontal axis, and the upper particle The pellets charged from the body charging port 8 are quantitatively stored in the pockets between the blades 3, transferred to the lower end by the rotation of the rotor 1, and discharged from the lower end discharging port 7 into the air transport pipe 6. ing. The problem of such a rotary valve is that the particles are caught between the outer peripheral edge of the blade 3 and the rotor case near the front edge A in the rotor rotation direction of the particle input port 8 and the particles are deformed. The phenomenon of crushing or crushing, that is, the phenomenon of biting occurs.

Therefore, as shown in FIG. 7, a baffle plate 10 having an inverted V-shaped lower end scraping edge 10a protruding rearward is arranged on the front side of the insertion port 8 in the rotor rotation direction, and the granules are formed. The structure is adopted to reduce the biting.

In the structure as shown in FIG. 7, the occurrence rate of particle entrapment changes depending on the magnitude of the cutting angle θ of the rotor 1, and the type of particles, that is, light soft pellets and heavy hard pellets. It also changes depending on the difference. FIG. 5 shows an example of the relationship between the biting rate and the cutting angle θ, where X1 is a general pellet and X2 is a soft pellet. In the case of general pellet X1, the cutting angle θ increases more, and the biting rate sharply decreases when it approaches approximately 30 °. On the other hand, the soft pellet X2 has a larger bite rate than the general case because the granules on the circumference of the rotary valve case are sandwiched between the case and the rotor by the rotation of the rotor and stretched. The biting rate decreases linearly as the cutting angle θ increases.

[0005]

[Problems to be solved by the device]

 As mentioned above, especially when using soft pellets, it is recommended to increase the cutting angle as much as possible to prevent biting, but make the shape of the blade 3 perpendicular to the rotation direction as shown in Fig. 7. If the cutting angle θ is further exceeded with a straight line shape, the ratio of the area of the baffle plate 10 to the total area of the input port 8 will increase too much, and the flow cross-sectional area of the granules will increase significantly. Therefore, the supply of granules is restricted more than necessary, and the smooth supply of granules is hindered.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problem, the device according to claim 1 of the present invention uses a rotor having a plurality of blades in order to obtain a large cutting angle without increasing the angle of the bottom of the baffle plate. It is rotatably supported around the horizontal axis in the rotor case, and the shape of the blade is V-shaped or curved to open backward in the blade rotation direction. Thus, a baffle plate having a scraping edge that projects backwards in an inverted V shape is provided. According to the second aspect of the present invention, in order to further improve the reduction of the biting rate of the granules, the tip portion in the radial direction of the blade is formed in a tapered shape.

[0007]

[Action]

 The granules that are thrown in through the granule feeding port are supplied to the rotor pockets, but protrude backward in the direction of rotation of the rotor in an inverted V shape, and are divided into left and right by the raised baffle plate in the center. At the same time, it is scraped off by the scraping edge at the lower end of the baffle plate. The scraped particles move to the left and right sides between the blade and the scraping edge, and are sequentially stored in the pocket.

[0008]

First Embodiment FIG. 1 is a vertical cross-sectional view of a rotary valve to which the present invention is applied. A rotor 21 is composed of a horizontal rotor shaft 22, a plurality of blades 23, a pair of left and right end plates 24, and the like. The rotor shaft 22 is rotatably supported in a cylindrical rotor case 25, and is rotated in the F direction at a predetermined speed by an appropriate drive mechanism. A plurality of blades 23 are radially provided on the outer periphery of the rotor shaft 22 at equal intervals in the circumferential direction, and each blade 23 and the end plate 24 form a plurality of pockets for accommodating granules having a constant volume.

A discharge port 27 is formed at the lower end of the rotor case 25, and the discharge port 27 is connected to a high-pressure gas type air transportation pipe 26. An inlet 28 is provided at the upper end of the rotor case 25, and a baffle plate 30 is provided at the front side of the inlet 28 in the rotor rotation direction.

In FIG. 2, which shows a plan view of the charging port 28, the charging port 28 is formed in a rectangular shape when viewed from above, and the baffle plate 30 provided on the front side is viewed in the rotation direction F when viewed from above. It has an inverted V-shaped lower end scraping edge 30a protruding toward the rear side. The baffle plate 30 has a ridge line 30b at the center in the left-right direction, and an inclined surface is formed from the ridge line 30b to the lower edge scraping edge 30a, and the ridge line 30b becomes lower as it goes backward. The edge 30c intersects the scraping edge 30a.

On the other hand, the blade 23 is formed in a V shape that opens rearward in the rotation direction. In other words, it can be said that it is formed in an inverted V shape so as to project forward in the rotation direction F. The angle θ2 of the scraping edge 30a of the baffle plate 30 with respect to the reference straight line S parallel to the rotor axis is set to, for example, 30 °, while the angle θ1 of the blade 23 with respect to the reference straight line S is, for example, 20 °. It is set to °. Therefore, the cutting angle θ of the entire rotor 21 is set to 50 °, for example.

Next, the operation will be described. In FIG. 1, a part of the granules charged into the charging port 28 from the upper hopper is directly supplied to the pocket of the rotor 21, and a part of the granular material is guided by the baffle plate 30 to reach the lower end of the charging port, and is put in the pocket. Supplied. Then, by the rotation of the rotor 21, it reaches the lower end outlet 27, is dropped and supplied into the air transport pipe 26, and is transported to the target location by the air flowing in the transport pipe 26. Even if the particles are protruding from the pocket when they are supplied into the above pocket, the gap between the blade 23 and the scraping edge 30a at the lower end of the baffle plate is, for example, 50 °, as shown in FIG. Since the cutting angle θ is secured, the above-mentioned protruding particles move smoothly to the left and right as the rotor 21 rotates, and during the movement, some are stored in the pocket and the rest are Supplied in the pocket.

During the discharging operation, the portion between the discharging port 27 and the charging port 28 is sealed by the fitting portion between the outer peripheral surface of the blade 23 of the rotor 21 and the inner peripheral surface of the rotor case 25, which allows the transport pipe It is possible to efficiently prevent the air in 26 from leaking to the inlet side.

Particularly, since the angle θ1 of the blade 23 with respect to the reference straight line S is suppressed to, for example, 20 °, in FIG. 1, at least the complete seal portion D between the blade 23 and the inner peripheral surface of the rotor case 1 is Two or more places can be secured in the front part and the rear part from the inlet 28, respectively. By the way, if the angle θ1 of the blade 23 becomes too large, for example, if it becomes larger than 30 °, the left and right end portions of the blade 23 are fitted to the inner peripheral surface of the rotor case at the rear side of the charging port 28. However, it is difficult to secure two or more complete seals D in the front part and the rear part of the charging port 28, because the central tip end is in the desired state of the charging port 28. become. Therefore, considering the sealing property, it is appropriate that the blade angle θ1 is about 20 ° to 30 °.

[0015]

[Another embodiment]

 (1) FIG. 3 shows an example in which the tip cross-sectional shape of the blade 23 is formed in a tapered shape according to the invention of claim 2 of the present application. Specifically, it is formed in a trapezoidal shape having an inclined surface on the rear side in the rotation direction. As a result, the phenomenon of the particles being caught between the rotor case 25 and the blade 23 can be further reduced. (2) FIG. 4 is another example of the cross-sectional shape of the tip of the blade 23, which is an example in which the tip is formed in a tapered shape and the tip is formed in an arc shape. (3) The blade may have a curved shape.

[0016]

[Effect of device]

 As described above, the invention according to claim 1 of the present application supports the rotor 21 having the plurality of blades 23 in the rotor case 25 so as to be rotatable about the horizontal axis, and the shape of the blade 23 is located rearward in the blade rotation direction. It has a V-shaped or curved shape that opens toward the bottom, and a lower end scraping edge 30a that projects backwardly in an inverted V-shape when viewed from above is provided at the grain inlet 27 provided in the upper portion of the rotor case 25. Since the baffle plate 30 is provided, a large cutting angle θ formed by the lower edge scraping edge 30a of the baffle plate 26 and the blade 23 can be obtained while suppressing the area of the baffle plate 26 shielded into the inlet 28. be able to. As a result, it is possible to secure a sufficiently large area of the supply port and to keep the supply of the granules smooth while reducing the biting rate. In particular, the effect is remarkable when a lightweight soft pellet is used as the material.

Since a large cutting angle θ is ensured by the inclination of both the baffle plate 30 and the blade 23, the inclination angle of the blade 23, that is, the angle θ1 with respect to the reference straight line parallel to the rotor axis is excessive. It is possible to sufficiently secure a complete seal portion D between the inner peripheral surface of the rotor case 25 and the rotor 21 and also to maintain a sufficient sealing property.

Further, as in the second aspect of the present invention, by forming the tip end portion of the blade 23 in the radial direction in a tapered shape, the phenomenon of the trapping of particles between the rotor case 25 and the blade 23 is further improved. Can be reduced.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a rotary valve to which the device according to claim 1 of the present application is applied.

FIG. 2 is a plan view of FIG.

FIG. 3 is a sectional view of a blade to which the device according to claim 2 of the present application is applied.

FIG. 4 is a sectional view of another blade to which the device according to claim 2 of the present application is applied.

FIG. 5 is a graph showing a relationship between a cutting angle and a biting rate.

FIG. 6 is a vertical sectional view of a conventional example.

FIG. 7 is a plan view of another conventional example.

[Explanation of symbols]

 21 rotor 23 blade 25 rotor case 27 discharge port 28 input port 30 baffle plate 30a scraping edge

Claims (2)

[Scope of utility model registration request] 1. A rotor having a plurality of blades is rotatably supported in a rotor case about a horizontal axis, and the shape of the blade is V-shaped or curved to open rearward in the blade rotation direction, and the upper part of the rotor case. A rotary valve, characterized in that a baffle plate having a lower end scraping edge projecting in an inverted V shape toward the rear when viewed from above is provided at the granule introducing port provided in the above. 2. The rotary valve according to claim 1, wherein the thickness of the tip of the blade in the radial direction is tapered.