JPS58187614A - Liquid-enclosed rotor - Google Patents

Abstract

PURPOSE:To prevent migration of liquid, staying at the inside, to a rim state and to prevent the production of unsteady vibration, by a method wherein a pluraity of beams are mounted in the vicinity of an inner wall of a cylinder part and in the direction of the axis of the cylinder part. CONSTITUTION:A pluraity of beams 7 are inserted through a cylinder part 1 and in a direction of the axis of the rotation, and the beams 7 pass through an opening formed in a peripheral direction of a flange 2 to be secured to the flange 2 with the aid of beam mounting means 8. By turning a liquid-enclosed rotor in a condition that liquid stays in the cylinder part 1 to some extent, liquid 6, gathering on the bottom, rises along a peripheral surface by a friction between liquid and the inner surface of the cylinder and a centrifugal force, and is going to be distributed along the inner periphery. However, the beams 7 disturb the layer of the liquid 6 and checks rising of the liquid 6 along the inner surface of the cylinder, whereby the liquid 6 is disturbed as if in a cascade state and migration to a rim state is delayed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid-filled rotor that can be generally applied to rotors that are filled with liquid, such as rotors for centrifuges and paper machines.

A rotating body is made hollow and a liquid such as water is poured into it.
There are methods for cooling or drying objects that come into contact with the outer surface of the rotating body or objects inside the rotating body. The rotating body used in this way is partially filled with liquid,
Hereinafter, this will be referred to as a liquid-filled rotor. A liquid-filled rotor also includes a device in which a gas such as water vapor is poured into the rotor, and the liquid is liquefied and remains in the rotating body as a drain or the like.

A conventional example of such a liquid-filled rotor is shown in FIG. In Figure 1, (1) is the cylindrical part, (2) is the 7 flange,
(3) is the shaft (also serves as the liquid supply hole in Figure 1),
(4) shows the bearing, (5) shows the liquid outlet, and (6) shows the liquid. The inside of the cylindrical part (1) is a hollow part,
A liquid (6) is enclosed. Enclosed liquid (6
) to prevent leakage to the outside and to transmit rotational torque.
A flange (2) is provided.

Furthermore, to rotate the cylinder filled with liquid (6)! +
l+ (3), which is supported by a bearing (4). Also, make the shaft (3) hollow and pour liquid into it from one side.
Extraction port (5) attached to the other shaft (3)
Remove the liquid from the. Here, we experimentally found that when the liquid-filled rotor is rotated with a certain amount of liquid accumulated in the cylindrical portion (1), the internal liquid forms the following state. That is, (a) When the rotational speed is slow, the liquid (6) simply accumulates near the bottom of the cylindrical portion (1) and does not rotate. This state is called the pound state (Figure 2).

(b) Next, as the rotation speed is further increased from this pound state, the shape of the liquid accumulated at the bottom of the cylindrical part (1) gradually develops into a crescent shape, and the tip of the crescent shape is shaped by gravity. It will lead to collapse. This state of collapse is called a cascade state (Figure 3).

(Q) As the rotational speed is further increased from this cascade state, the liquid forms a thin layer of liquid over the entire circumference of the cylindrical portion (1). In this way, the liquid has a certain thickness and rotates in a layered manner over the entire circumference at the same circumferential speed as the cylindrical part (1). This state is called the rim state (Fig. 4).

(d) Next, when the rotational speed is lowered from when the liquid is in a rim state, the liquid layer surrounding the inner surface of the cylindrical part ( ) gradually loses its centrifugal force and falls to the bottom of the cylinder. This state is called a collapse state (it is the same form as the cascade state shown in FIG. 8).

In the above state, the rotational speed at which the collapsed state normally occurs is lower than the rotational speed at which the rim state occurs.

That is, when the liquid-filled rotor speeds up and when the speed increases, the above (a)
) to (d) have a history and do not match. Further, depending on the amount of liquid accumulated inside the cylinder, the number of rotations at which each of the above states is reached changes, and in particular, the number of rotations at which the rim state is reached becomes lower as the amount of liquid is smaller.

On the other hand, as a result of experiments, it was found that the influence of the liquid (6) on the vibration of the liquid-filled rotor is as follows.

When the liquid (6) is in the rim state, the critical speed of the liquid-filled rotor decreases at a greater rate than in the states (a) and (b). That is, regardless of the amount of liquid (6) sealed, the critical speed of the liquid-filled rotor decreases to about the critical speed when the container is full of liquid. Furthermore, there is almost no damping effect due to the liquid. Therefore, passing the critical speed in the rim state is more difficult than in the case without sealing.

■ After the liquid (6) passes through the reduced critical speed in the rim state, self-excited vibrations may occur. At this time, the liquid flows against the inner surface of the cylinder.

■ As it transitions to the liquid (6) calim state, the critical speed decreases with the transition, causing a transient change in vibration.

In addition, even if the liquid-filled rotor is operated in any of the conditions (a) and (b) above and vibration is not a problem, the amount of liquid (6) remaining inside the cylinder will decrease. If this occurs, the liquid may suddenly shift to the rim state, which may lead to the vibrations described in ■■■ above.

The present invention was proposed in order to eliminate the above-mentioned conventional drawbacks, and by installing a plurality of beams in the axial direction of the cylindrical part in close proximity to the inner wall of the cylindrical part, the liquid accumulated inside can be removed. It is an object of the present invention to provide a liquid-filled rotor that can be prevented from shifting to a rim state and can be rotated stably without generating unstable vibrations.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 5 shows the structure of a liquid-filled rotor showing an embodiment of the present invention.

In the figure, (1) is the cylindrical part, (2) is the 7 flange (end plate), (3) is the shaft, (4) is the bearing, (5) is the liquid outlet, and (6) is the liquid. , are the same as those shown in Fig. 1. Further, (7) is a beam, and (8) is a beam fixture. 6 is a cross-section AA of FIG. 5 viewed in the direction of the arrow, and FIG. 7 is a cross-section BB of FIG. 5 viewed in the direction of the arrow.

In Fig. 5, the cylindrical part (1)
A plurality of beams (7) are passed through an opening provided in the circumferential direction of the flange (2), for example, through an opening provided in the circumferential direction of the flange (2), and a plurality of beams (7) are passed in the direction of the internal rotational axis. ), (Beam attachment is not limited to the structure of this example, and may be attached by welding to the flange (2), etc.).The beam (7) is not rotating. ,!
: Attach it in a radial position so that it is fully immersed in the liquid (6). Note that beams (although the cross section of the sword is not particularly limited, piano wire may be substituted, or wire (
It is also possible to use a ridge line) as a substitute.

Now, when the liquid-filled rotor is rotated with a certain amount of liquid accumulated in the cylindrical part (1), the liquid (6) accumulated at the bottom of the cylindrical part (1) will cause friction between the liquid (6) and the inner surface of the cylinder. The centrifugal force causes the inner surface of the circumference to rise, and the cylindrical part (1
).

However, the beam (force) disturbs the layer of liquid (6) and
is prevented from rising on the circumferential inner surface, so the liquid (6) is disturbed in a cascade-like manner and the transition to the rim state is delayed.

Due to this action, the liquid becomes in a rim state, and the cause of large vibrations in the liquid-filled rotor is partially eliminated, and the range in which the liquid-filled rotor can be stably rotated is widened.

Furthermore, even when self-excited vibration occurs under the rim condition, the presence of the beam creates a resistance action against the flow of liquid against the inner wall of the cylinder, making it possible to eliminate or reduce the self-excited vibration generation region. Note that the above explanation was for the case of liquid encapsulation, but
The beam effect is equally effective when powder or granules are enclosed.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an example of a conventional liquid-filled rotor;
FIGS. 2, 3, and 4 are explanatory diagrams showing the state of the liquid layer inside the cylinder, respectively. FIG. 5 is a side sectional view of a liquid-filled rotor showing an embodiment of the present invention. FIG. FIG. 7 is a sectional view taken along line AA in the figure, and FIG. 7 is a sectional view taken along line BB in FIG. Explanation of the main parts of the diagram■...Cylindrical part 3...Shaft 6...Liquid? ... Liang patent applicant Mitsubishi Heavy Industries, Ltd.

Claims (1)

[Claims] A liquid-filled rotor characterized in that a plurality of beams are installed in the axial direction of the cylindrical part in close proximity to the inner wall of the cylindrical part.