JP2000279782A - Agitator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agitator compact in structure, low in cost and easy in maintenance without impairing the necessary function for the agitator. SOLUTION: An agitating vessel 11 is provided with a shaft sealing device 16. A rotary driving part of a rotating shaft 18 is mounted on the shaft sealing device 16. A hollow shaft 20 is inserted from the shaft sealing device 16 to the driving part. An agitating shaft 19 projecting to outside the vessel from inside the agitating vessel 11 is inserted into the hollow shaft 20 and is fixed to the hollow shaft 20 in the driving part. The hollow shaft 20 is pivotally supported in the driving part and is connected to a driving motor 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stirrer, and more particularly to a stirrer shaft and a transmission structure of a stirrer shaft for sealing a stirrer shaft projecting outward from a stirrer and connecting the stirrer shaft to a rotary drive unit. About.

[0002]

2. Description of the Related Art High temperature (or low temperature) stored in a container,
A stirrer that stirs and mixes a flowing or semi-flowing substance under high-pressure (or reduced-pressure) conditions rotates a stirring blade fixed to a stirring shaft in the vessel, and outputs power from the vessel to the outside. In this configuration, the shaft end of the agitating shaft protruding from the shaft is connected to an external drive source. As such a stirrer, there are a vertical stirrer in which a stirrer shaft is arranged vertically and a horizontal stirrer in which a stirrer shaft is horizontally arranged, and a power transmission and shaft sealing mechanism to the stirrer shaft of the vertical stirrer. Generally has a structure as shown in FIG.

A vertically long base 10 is provided above the center of a stirring vessel 11.
The rotary drive motor 1 and the speed reducer 2 are mounted on the gantry 10. The output shaft of the speed reducer 2 extends into the gantry 10 and is connected to the drive shaft 8 below the flexible shaft coupling 3. The drive shaft 8 is supported by the upper bearing 4 held by the inner flange 15 interposed in the middle of the gantry, and is further connected to the seal shaft 9 by the fixed shaft coupling 5. The periphery of the seal shaft 9 is sealed by a shaft sealing device 6 such as a mechanical seal so as to isolate the inside of the container 11 from the gantry 10 side (atmosphere side), and a lower bearing built in the shaft sealing device 6. (Not shown), the lower end of which is inserted into the container. In addition,
The shaft sealing device 6 is fixed to a pedestal 13 fixed to an opening at the center upper end of the container.

[0004] A seal shaft 9 protruding into the container 11 from the opening of the pedestal 13 at the top of the container is connected to the upper end of the stirring shaft 12 via a fixed shaft coupling 7 in the container 11. Stirring shaft 12
Stirring blades are attached to the middle to lower portions, but these stirring blades are not shown in FIG. Here flexible shaft coupling 3
The lower drive shaft 8, the seal shaft 9 and the stirring shaft 12 are firmly connected as a single rotation shaft by fixed shaft couplings 5 and 7, respectively, and the rotation output of the motor 1 is optimized for the rotation operation by the speed reducer 2. The rotational speed is converted to torque and transmitted to the rotary shaft via the flexible shaft coupling 3. The flexible shaft coupling 3 absorbs elastic deformation and thermal deformation of the rotating shaft, particularly shaft deformation due to the bending of the seal shaft 9 in the shaft sealing device 6. In this structure, each component member is indispensable as a rotational force transmission and sealing mechanism, and a function as a stirrer is achieved by assembling and connecting the respective mechanism parts.

[0005]

The above-mentioned conventional structure is a structure in which the shaft from the drive unit to the inside of the container is divided, and each structure is integrally connected by a shaft joint and supported by a bearing. Has a configuration independent of the driving unit, the transmission unit, and the shaft sealing unit. For this reason, the overall size is inevitably large, and the maintenance requires complicated work such as disassembly of each part. Usually, the upper part of the container where the stirrer is installed is equipped with various pipes and instrumentation equipment, and various operations and work spaces are required, so a large stirrer tends to cause various troubles. is there.

In the conventional structure described above, various functional parts (motors, reduction gears, mechanical seals, etc.) are individually procured from commercially available products, and bearing boxes, shaft couplings, etc. are added so that they can be operated without difficulty. However, the overall structure is made up, and from the viewpoint of equipment cost, redundant and useless components are required, which eventually leads to an increase in the size of the whole.

An object of the present invention is to provide a compact, low-cost, and easy-to-maintain vertical stirrer that eliminates the above-mentioned problems and does not impair the required function of the stirrer.

[0008]

According to the present invention, a shaft sealing device is installed in a stirring vessel, and a rotary drive unit for a stirring shaft is mounted on the shaft sealing device. From the shaft sealing device to the driving unit, A hollow shaft is inserted, and a stirring shaft protruding from the inside of the stirring container to the outside of the container is inserted into the hollow shaft and fixed to the hollow shaft in the drive unit, and the hollow shaft is supported and supported in the drive unit. An agitator operatively connected to the drive motor is provided.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a stirring shaft driving portion of a vertical stirrer according to an embodiment of the present invention. Attachment seat 11a at the opening in the upper center of the stirring vessel 11
The casing 17 of the shaft sealing device 16 is installed, and a transmission / reduction gear box 18 is further mounted thereon. Stirring shaft 19
Protrudes from the opening of the container 11 through the shaft sealing device 16 to the upper part of the transmission box 18. Stirring shaft 19
A hollow shaft 20 is arranged on the outer periphery of the shaft from the speed changer box 18 to the shaft sealing device 16 over substantially the entire length thereof. In addition, a rotation drive motor 21 is mounted above the transmission / reduction gear box 18 at a position shifted from the axis of the stirring shaft 19.

The stirring shaft 19 is taperedly fitted (indicated by reference numeral 22) with the hollow shaft 20 in the transmission box 18, and both are firmly fixed by a key and fixing bolts 23. In a portion corresponding to the shaft sealing device 16, the hollow shaft 20 is formed to have an inner diameter slightly larger than the outer diameter of the stirring shaft 19, so that a certain gap S between the hollow shaft 20 and the stirring shaft 19 is formed. Has occurred. Specifically, in the illustrated embodiment, the inner diameter of the hollow shaft 20 is formed in a tapered shape from the point corresponding to the upper part of the shaft sealing device 16 to the lower end, and the lower end of the hollow shaft 20 is connected to the stirring shaft 19. A slight gap S is generated between them. The outer periphery of the hollow shaft 20 in the shaft sealing device 16 is sealed to the shaft sealing device casing 17 by a mechanical seal 25 so as to shut off the inside of the container 11 from the outside air. In the variable speed reducer, the outer periphery of the hollow shaft 20 is supported by bearings 26 and 27 at two upper and lower portions, and a driven gear 28 is fixed to a middle portion of the hollow shaft 20 by a key.
The driven gear 28 meshes with a driving gear (not shown) fixed to the output shaft of the driving motor 21, thereby forming the hollow shaft 20.
The rotational power of the motor 21 is changed and decelerated and transmitted to the agitating shaft 19 via the motor. The lower end of the stirring shaft 19 is connected to a blade shaft on which a stirring blade is mounted, but this portion is not shown in FIG. Further, the hollow shaft 20 and the stirring shaft 19 are not limited to the above-described taper fitting, and may be other commonly used fixing means.

With such a configuration, the rotation output of the drive motor 21 is reduced to the required speed by the variable speed reducer in the variable speed reducer box 18 and transmitted to the stirring shaft 19 as described above.
The stirring shaft 19 itself is supported only at two places via the hollow shaft 20, and the shaft sealing device 16 seals the hollow shaft 20 at a position immediately close to the variable speed reducer and extending from the variable speed reducer. Because of the configuration, the shaft runout of the hollow shaft 20 is extremely small, and a bearing such as a mechanical seal built-in bearing is not required. Further, the shaft displacement due to shaft vibration, shaft deflection, and other elastic deformation due to power transmission of the stirring shaft 19, or thermal deformation is absorbed by the gap S between the inner periphery of the hollow shaft and the outer periphery of the stirring shaft. The displacement does not affect the mechanical seal 25 of the shaft sealing device 16. The amount of the gap between the hollow shaft 20 and the stirring shaft 19 depends on the capacity of the stirrer to be applied, the rotation speed of the stirring shaft 19, or the type of the substance to be stirred. A dimension sufficiently exceeding the displacement amount, for example, 0.
It is set to about 5-5 mm. Since there is no need to consider the influence on the seal portion, the outer diameter of the stirring shaft 19 can be the shaft diameter necessary only for power transmission required for the stirring operation, and the shaft diameter can be made smaller than before.

Further, according to the present invention, the weight of the drive motor 21 and the speed reducer is supported by the casing 17 of the shaft sealing device 16 itself. Simplified. When the drive units such as the drive motor 21 and the speed reducer become large and become unstable, an appropriate number of columns may be installed around the drive unit. In the illustrated embodiment, the axis of the motor 21 and the axis of the stirring shaft 19 are shifted from each other, but the present invention is not necessarily limited to this embodiment. The motor may be placed horizontally, that is, horizontally, and the axis of the motor and the stirring shaft 19 may be arranged orthogonally via a gear mechanism such as a worm gear structure. In the above-described embodiment, the vertical stirrer has been described as an example. However, the present invention is characterized in that the shaft sealing device 16 and the speed changer box 18 are integrated via the hollow shaft 20. It is equally applicable to machines.

[0013]

As described above, according to the present invention, the shaft sealing device and the drive unit are mounted on the stirring container in a form of a directly connected integral structure, and the stirring shaft is penetrated from the shaft sealing device to the variable speed reducer. A hollow shaft is arranged on the outer periphery of the stirring shaft, and a gap is formed between the stirring shaft and the lower half of the hollow shaft. Thus, a compact, lightweight, low-cost agitator that secures the necessary functions of each part without obtaining the shaft displacement of the agitating shaft does not affect the axle sealing device.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a stirring shaft driving portion of a vertical stirrer according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of a stirring shaft driving portion of a conventional vertical stirrer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Stirring container 12 Stirring shaft 16 Shaft sealing device 17 Shaft sealing device casing 18 Variable speed reduction box 19 Stirring shaft 20 Hollow shaft 21 Drive motor 25 Mechanical seal 26, 27 Bearing

Claims (2)

[Claims] 1. A shaft sealing device is installed in a stirring vessel, a rotation drive unit for a stirring shaft is mounted on the shaft sealing device, a hollow shaft is inserted from the shaft sealing device to the driving unit, and A stirring shaft protruding out of the container is inserted into the hollow shaft and fixed to the hollow shaft in the drive unit, and the hollow shaft is bearing-supported in the drive unit and is operatively connected to a drive motor. And a stirrer. 2. A gap is formed in the shaft sealing device between an inner periphery of the hollow shaft and an outer periphery of the stirring shaft, and an outer periphery of the hollow shaft is sealed with respect to a shaft sealing device casing. The stirrer according to claim 1, wherein: