JPS6115948Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stabilizer ring for a stirring blade.

In a stirrer, when the length of the stirring shaft is particularly long, the operating rotational speed required for stirring approaches the critical rotational speed of the stirring shaft system, and the vibration of the stirring shaft becomes large during operation.

Also, vibrations become large when the liquid level fluctuates and passes through the stirring blade during stirring, or when the liquid level is operated at 1.5 d or less (a=diameter of the stirring blade).

In such cases, a method is generally taken to prevent vibration by attaching a stabilizer ring to the lowest stirring blade.

A conventional stabilizer ring has a single cylindrical ring attached to the lower discharge side of the stirring blade, and is intended to prevent vibration of the stirring blade by the resistance of the ring surface.

However, stabilizer rings are not necessarily stable against vibrations either. Particularly when the liquid is violently turbulent, such as when passing through the liquid surface, it may even cause vibration. This is because the turbulence of the liquid inside the ring becomes extremely large and unstable.
This is because the pressure difference between the inside and outside of the ring fluctuates as a result, which causes vibration.

In view of this, the present invention aims to eliminate the drawbacks of the conventional stabilizer ring by forming the stabilizer ring into a double cylinder to eliminate fluctuations in the pressure difference between the inside and outside of the stabilizer and to prevent vibrations of the stirring blades.

The outer diameter of the inner ring is approximately 70% of the outer diameter of the outer ring.
is appropriate. That is, the ring gap cross-sectional area and the inner ring cross-sectional area are made approximately equal.

As mentioned above, when the stabilizer ring is formed into a double cylinder, the flow rate of the downward discharge flow of the stirring blade passing through the gap of the double cylinder is larger than the flow rate passing through the inner ring. The flow passing through the gap flows down at a high velocity. Therefore, the dynamic pressure inside the gap becomes negative pressure, and the liquid is sucked in to increase the negative pressure, reaching a state of equilibrium with the frictional resistance in the gap and maintaining a constant negative pressure.

In this way, it is possible to exert its original effect as a stabilizer ring without causing harmful pressure fluctuations with the external fluid, and to prevent vibrations of the stirring blades and stirring shaft.

Furthermore, if the stirring flow is severely disturbed, a plurality of rectifying plates may be provided in the gap between the double cylinders to further ensure the vibration damping effect of the stirring blades.

As a general rule, the current plate should be used in the gap between the double cylinders.
Divide it equally into 4, 6, etc.

If the stirring flow is particularly turbulent, arrange the current plate irregularly.

As described above, when a rectifying plate is provided in the gap between the double cylinders, the flow flowing down the gap is rectified and flows at a uniform flow velocity, so the dynamic pressure of the flow also becomes more uniform and negative. Since the inside of the ring gap becomes a more even negative pressure, the vibration damping effect of the stirring blade is further ensured.

Next, embodiments of the present invention will be described.

FIG. 1 is a sectional view of a stirring device having a conventional stirring blade with a stabilizer ring, FIG. 2 is a detailed sectional view of a stirring blade with a stabilizer ring according to claim 1, and FIGS. 3 and 4 are , which shows a plan view of the stabilizer ring according to claim 2.

In the figure, 1 is a stirring blade, 2 is a stabilizer ring made of a double cylinder, 3 is an inner ring, 4 is a gap between the double cylinders, and 5 is a current plate provided in the gap 4.

In FIG. 3, the gap 4 is divided into four equal parts and a rectifying plate 5 is provided. The discharge flow a from the stirring blade is rectified in the gap 4 and flows down at a flow velocity higher than the flow velocity b in the inner ring, so according to Bernoulli's theorem, the dynamic pressure in the gap becomes a uniform negative pressure.
Since harmful pressure fluctuations do not occur between the stabilizer ring and the external fluid C, the stabilizer can effectively exhibit its original vibration damping effect. It is better to increase the number of rectifying plates 5 as the diameter of the stabilizer ring becomes larger.

If the turbulence of the stirring flow is particularly severe, the current plate 5
It is effective to arrange them irregularly as shown in FIG. Figure 4 shows the circumference of the ring with a random number of 5,
Divided into ratios of 3, 7, 4, 3, 5, the current plate 5
It has 6 sheets.

In this case, the flow velocity passing through the ring division gaps 4a, 4b, etc. is not the same due to resistance due to the size of the flow path, so the dynamic pressure is also not constant and is different in each division.

Therefore, if the external fluid is highly turbulent and the dynamic pressure fluctuates greatly, during one revolution of the stabilizer ring, there is a high possibility that the dynamic pressure fluctuations within the ring will cancel each other out and the fluctuating differential pressure will become zero. The stirring blades do not generate large vibrations.

As described above, the present invention replaces the conventional single ring with a double cylindrical stabilizer ring for the stirring blade, or installs a plurality of rectifying plates in the gap between the cylinders to further enhance the stabilizer ring. It is stable and can exhibit an effective effect in preventing vibration of the stirring blade.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a stirring device having a conventional stirring blade with a stabilizer, Fig. 2 is a detailed sectional view of the stirring blade of the present invention, and Figs. 3 and 4 are stabilizer rings of different embodiments. The top view of the figure is shown. 1... Stirring blade, 2... Stabilizer ring,
3... Inner ring, 4... Gap, 5... Current plate.

Claims (1)

[Claims for Utility Model Registration] (1) A stabilizer ring for a stirring blade characterized by a double cylinder provided at the bottom of the stirring blade. (2) The stabilizer ring according to claim 1, which is a utility model registration, characterized in that a plurality of rectifier plates are provided in the gap between the double cylinders.