JPS63160926A - Rotary feeder for pneumatic transportation - Google Patents

Abstract

PURPOSE:To have sure shutoff performance against leakage by combining a rotor with a rotary shaft with capability of being eccentric to the later named, and allowing the rotor to make contact in the neighborhood of the upper or lower opening. CONSTITUTION:An upper opening 1-1 and a lower opening 1-2 are connected to a pulverized/granular substance supply system and a transport system using high pressure air, respectively. Because the lower opening 1-2 is connected with transport system, the differential pressure to the upper opening 1-1 heaves a rotor 2 when transport is commenced and the intrasystem pressure rises to reach a certain specified level, and the heaved rotor 2 contacts the interior surface of the casing on the upper opening side to provide shutting-off. If in this condition the rotary shaft 3 is rotated, the rotor 2 in fitting at the square section rotates while in contact with the peripheral surface of the upper opening. Therefore, constant supply of pulverized/granular substance is made while the high pressure air is hindered from leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention has a rotary feeder used in a pneumatic conveyance device for powder and granular materials, which improves the ability to block airflow due to the vertical pressure difference and reduces leakage. This invention relates to a rotary feeder that can be used in high-pressure transportation systems.

Conventional technology The rotary feeder has a simple structure of rotating a rotor within a casing and is capable of dropping a fixed amount of powder and granules. Or it is widely used for mixing.

This is because the rotary feeder can easily block the pressure difference between the upper and lower sides and supply powder and granules to the transportation system while maintaining airtightness. Moreover, it is relatively small and has a simple structure, and the rotation speed of the rotor can be adjusted. This is because it is possible to supply a fixed amount at will.

As mentioned above, [1- Since the tally feeder blocks the pressure of the transport system and uses gravity to drop the powder, the smaller the gap between the rotor and the casing, the better. However, in order to solve processing problems such as incorporating the rotor into the casing, or operational problems where rotational resistance becomes excessive due to entanglement of powder particles or thermal expansion of the rotor, making operation difficult, the casing and rotor You need to make a suitable amount of rice in between.

By the way, the above-mentioned gap must be kept to the minimum necessary level since it causes air leakage due to the pressure difference and reduces the sealing performance.

More specifically, the clearance between the casing and rotor is
As the pressure difference between the upper and lower sides increases, the amount of pressure gas leaking increases. Furthermore, as the apparent specific gravity of the transported object becomes smaller, the falling of the transported object becomes smaller or uneven due to the headwind of the leaked gas, making it difficult to supply a constant quantity.

Therefore, the limit of the pressure difference between the upper and lower sides that can be used with a rotary feeder is usually 017 atm or less, and for example, in the case of particles with an apparent specific gravity of around 0.51/m',
0-7000mm) (20, 3000-4000mm for powder)
mm) I20 is said to be the practical limit.

However, recently, in order to improve the efficiency of pneumatic transport, it has become desirable to achieve higher transport pressure.

Therefore, in order to increase the transportation pressure, two methods are used to reduce the amount of leakage by installing a rotary feeder in two stages, or by installing an elastic member at the tip of the rotor blade and sliding it in contact with the fitting circumferential surface of the casing. Attempts have been made to reduce the amount of leakage.

However, in the former case, the leakage amount is 0 compared to the case of 1 stage.
It can only be reduced by about %, and sufficient effects cannot be obtained. In the latter case, the durability of the sealing elastic material becomes a problem, requiring frequent replacement and repair, which is economically disadvantageous.

Problems to be Solved by the Invention In view of the above-mentioned current situation, the present invention provides an appropriate clearance between the casing and the rotor, which makes it easy to assemble the rotary feeder, and also allows the rotary feeder to be assembled under -F pressure during use. It is an object of the present invention to provide a rotary feeder in which a rotor is brought into contact with the vicinity of an upper opening or a lower opening by utilizing differential pressure caused by a difference to ensure leakage protection.

Means for Solving the Problems The present invention provides a rotary feeder in which a rotor is incorporated into a casing having an upper opening and a lower opening, with the rotating shaft of the rotor being pivotally supported. The rotor is assembled eccentrically with respect to the rotating shaft so that the rotor can be brought into contact with the rotating shaft.

In this invention, as a means for eccentrically assembling the rotor with respect to the rotating shaft, as shown in FIG. To enable transmission, a spline part is provided on the rotating shaft as shown in FIG. As shown in the figure, any method can be selected as long as the rotation can be transmitted, such as by interposing flexible joints on both ends of the rotor on which the rotor is fitted, so that the rotor can be freely eccentric.

In addition, the rotating shaft does not have both ends supported, but only one side of the shaft is supported, as shown in Figure 5, and a joint is interposed between the rotor and the rotating shaft, so that the rotor can be freely eccentric. Built-in rotation can be transmitted to.

Function: Since the rotor in this invention is installed eccentrically with respect to the rotating shaft, if there is a pressure difference between the feeding system and the transport system in a powder transport device, the rotor will be pushed due to the pressure difference. When the transport system is under high pressure, the rotor rotates in a state in which it contacts or is on the verge of contact with the upper opening side, that is, in a state where the clearance is close to zero, and leakage is blocked. Further, when the transport system is under negative pressure, contrary to the above, the rotor is pushed toward the lower opening and rotates while blocking the lower opening.

Here, we will discuss the floating eccentricity of the rotor due to the differential pressure of pressurized air. For example, if the dimensions of a rotor with a volume of 20 rl are both 23 cm in diameter and length, the projected area in that case will be 529 d. Also, the unit weight of this rotor is approximately 50
It is 9.

When the pressure of the transport air is set to 0.5 to 9, the differential pressure acting on the rotor is approximately 265 kg, and even if there is a counterbalance condition of the flow of the transported object, the rotor can float eccentrically without any problem.

Embodiments Embodiment 1 An embodiment of the present invention will be explained based on FIGS. 1 and 2.

In the drawing, (1) is a casing having an upper opening (1-1) and a lower opening (1-2), and (2) is a rotating shaft (3).
The rotor (4) is a side plate of the casing, and the shaft neck portion of the rotating shaft (3) is supported by a bearing (5) provided at the center of the rotor (4). (6) is a backing, and (7) is a bearing cover.

The rotor fitting portion of the rotating shaft (3) has a square chamfered cross section, and the rotor fitting hole (8) corresponding thereto also has a square chamfered cross section and is slightly larger than the rotating shaft (3) so that a gap is created between the two. Provided for. A flange (9) for locking the rotor is provided at the end of the rotor fitting portion, and a collar (10) is screwed to the other end to prevent the rotor (2) from moving in the axial direction.

The casing (1) and rotor (2) assembled as described above.
) is normally 10. The clearance due to the dimensional difference between the rotating shaft (3) and the rotor fitting hole (8) should also be set at about the correct m or slightly larger.

Therefore, the upper opening (1-1) side and the lower opening (1-2) side
) side, the rotor (2), which is fitted loosely with respect to the rotating shaft (3) with a clearance, is eccentric downward due to its own weight and comes into contact with the inner peripheral surface of the casing on the lower opening (1-2) side. ing.

Now, when using a powder pneumatic transportation device (not shown), the upper opening (j-1) is connected to the powder supply system and the lower opening (1-2) is connected to a transportation system using high-pressure air. Explain the operation.

Since the lower opening (1-2) side is connected to the transport system,
When transportation starts and the pressure in the system rises and reaches a predetermined pressure, the pressure difference between the upper opening (ii) and the
) is pushed up and comes into contact with the inner circumferential surface of the casing on the upper opening (ii) side and is blocked.

When the rotating shaft (3) is rotated in this state, the rotor (2) fitted with a square cross section rotates while being in contact with the circumferential surface of the lower opening, as shown in FIG. 2B. Therefore, the powder and granular material can be supplied in a fixed amount while blocking the leakage of high-pressure air.

Also, contrary to the above embodiment, the pressure on the transport system side is low and the lower opening (
When negative pressure acts on the 1-2) side, the rotor (2) rotates while contacting the lower opening peripheral surface.

As mentioned above, since the rotary feeder according to the present invention always rotates with the 11-ta in contact with a part of the inner peripheral surface of the casing, it is necessary to take measures to prevent seizure.

As a countermeasure, for example, the inner circumferential surface of the casing and the outer circumferential surface of the rotor are coated or overlaid with a hard metal.
The contact surfaces between the two are made highly hard and have a mirror finish.

In the above embodiment, the rotor (2) is loosely fitted to the rotating shaft (3) with a clearance, and the rotor can be eccentric.As shown in FIG. The fitting hole (
11) is a circular hole, and a pair of protrusions (12) in the axial direction are provided on the inner circumferential surface of the hole, and the rotating shaft (3) inserted into the fitting hole (11) is fitted. The part facing the hole (11) is a plate part (3-1) with a width slightly smaller than the diameter of the fitting hole, and there is a gap between the two so that the rotation is transmitted although there is a loose fit. (2) is pushed and moved when differential pressure acts on it, making it eccentric to the rotating shaft (3), or as shown in Figure 4, the rotating shaft (3) fitted with the rotor (2) is By cutting the rotating shaft on both sides of the rotor and joining them with flexible joints (13) (13), the rotor (2) is made eccentric to the rotating shaft (3) using a uniform means. [1-Y] can be provided eccentrically at will.

Embodiment 2 FIG. 5 shows a case where the rotating shaft (3) of the 0-tar (2) is used as a one-sided support shaft.

A bearing unit (with two sets of bearings, a roller bearing (14) and a ball bearing (15) on the right side of the casing (1)
16), on which the rotating shaft (3) is pivotally supported. This rotating shaft (3) has a protruding piece (17) on the plate at the joint end with the rotor.
) is provided protrudingly, and the opposite end face of the rotor (2) is provided with 1
A pair of protrusions (18) are provided to protrude from the plate-shaped protrusion (17).
) are engaged and combined so that rotation can be transmitted.

In addition, as shown in Fig. 3, there is a play of 1 rotor (2) on the rotating shaft (3).
In the case (2), and also in the case where the rotor (2) shown in FIG. 4 is supported via the flexible joint (13), the rotating shaft (3) can be made into a one-sided support shaft.

Effects of the Invention This invention provides a rotary feeder in which the rotor is provided eccentrically with respect to the rotating shaft, and when in use, the pressure difference between the upper and lower pipes presses the opening toward the lower opening side or the upper opening side to close the opening. Since it can be rotated in a closed state, it is possible to prevent leakage of high-pressure air and supply a fixed amount of powder or granular material. Therefore, the transportation efficiency in high-pressure pneumatic transportation can be improved.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of the rotary feeder according to the first embodiment of the present invention, Fig. 2 Δ is a central sectional view of the same -F, and Fig. B is the rotor when differential pressure is applied from the lower opening side. FIG. 3 is a central sectional view showing the eccentric state, FIG.
Figure B is a sectional view on the line m-■ of the Δ diagram, Figure 4 is a front view showing the rotor and rotating shaft in the third embodiment, and Figure 5 is the second embodiment.
They are a longitudinal cross-sectional view (A figure) and a joint part view (B figure) of a rotary feeder in . 1... Casing 1-1... Upper opening 1-2... Lower opening 3
...Rotating shaft 3-1...Plate-shaped part 4...
Side plate 5...Bearing 6...Backing
7... Bearing cover 8... Fitting hole
9...Flange 10...Color 11.
...Fitting hole 12...Protrusion 13...Flexible joint 14...Roller bearing 15...Ball bearing 16...+11+Ball bearing i.11...Plate-like protrusion 18...・Protrusion 19...Fitting hole Applicant Sankan Air Equipment Co., Ltd. Agent Patent attorney Yoshihisa Oshida 1IfI1 Figure 2 Figure 1 $5 (A) (B) Figure 3 (A) Figure 4 ( B)

Claims (1)

[Claims] In a rotary feeder in which a rotor is built into a casing having an upper opening and a lower opening, with the rotor's rotating shaft being pivotally supported, the rotor can be freely eccentric with respect to the rotating shaft so that it can come into contact with the inner circumferential surface of the casing near the upper and lower openings. A rotary feeder for pneumatic transportation characterized by a combination of a rotor and a rotor.