JPH042293B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a stirring device for liquids and liquids, liquids and solids, and particularly to a stirring device that requires stirring under vacuum or pressure.

[Conventional technology]

When the inside of a stirring tank is brought to a pressure different from atmospheric pressure, such as a vacuum or high pressure, conventional stirring devices install an electric motor outside the stirring tank, and move stirring tools such as stirring blades inside the stirring tank to the inside of the stirring tank. It was rotated by a drive shaft that penetrated the wall. A mechanical seal or magnetic fluid seal was applied to the portion where the drive shaft penetrated the tank wall.

Various types of stirring devices have also been developed that do not have a drive shaft that penetrates the tank wall. For example, a permanent magnet is placed inside the stirring tank and an appropriate magnetic field is applied from outside the tank to drive it to rotate, or a stirring device that does not have a drive shaft that penetrates the tank wall. There was one in which a stirring cylinder corresponding to the rotor of an electric motor was provided, and a winding corresponding to the stator of the electric motor was provided outside the stirring tank to rotate the stirring cylinder inside.

[Problem that the invention seeks to solve]

However, in most stirring devices that have a drive shaft that penetrates the tank wall, the stirring shaft is cantilevered, which causes the shaft to shake, resulting in incomplete sealing, especially in the case of mechanical seals. There was a problem in that lubricating oil or bacteria could get mixed into the tank due to oil leakage.

Another problem is that when a magnetic fluid seal is used, it evaporates, making it difficult to use at a high temperature of 80° C. or higher or in a vacuum.

In the above-mentioned stirring device that applies an appropriate magnetic field to the outside of the stirring tank to rotate a stirring cylinder or the like disposed inside the stirring tank, a tank wall and an appropriate gap are provided between the primary side and the secondary side. Therefore, there was a problem that the efficiency was lower than that of ordinary electric motors.

Furthermore, when metal is used for the tank, there is a problem in that eddy currents flow due to changes in magnetic flux, which further reduces efficiency.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a stirring device that prevents foreign matter from being mixed into the raw material to be stirred under vacuum or pressure, and that has high stirring efficiency.

[Means to solve problems]

The stirring device according to the present invention, which achieves the above object, includes a stirring tank that can be closed, a stirring chamber for charging and stirring raw materials, and an electric motor for rotating a stirring tool in the stirring chamber via a drive shaft. and a motor chamber, and the motor chamber is filled with a liquid that can be mixed with the solvent or raw material used for stirring,
Moreover, the pressure in the space between the stirring chamber and the motor chamber is configured to be approximately constant.

Here, the motor is preferably a cage-type multipolar induction motor, and its rated frequency is preferably lower than the commercial frequency, and the fixed winding of the motor is made of Teflon-based material that is resistant to chemicals and heat. Alternatively, ceramic insulated wires are used,
It is preferable that the windings of each phase that can be used in the liquid be connected outside the tank.

[Effect]

The stirring device according to the present invention has a stirring tank that can be sealed,
The stirring chamber is divided into a stirring chamber and a motor chamber, and the stirring tool in the stirring chamber is connected to the electric motor via a drive shaft. Therefore, the drive shaft passes through the wall that partitions the stirring chamber and the motor room through an appropriate sealing means, but there is no problem in the motor room even if the solvent used for stirring or the raw materials to be stirred get mixed in. Since the tank is filled with liquid, even if liquid leaks from the motor chamber into the stirring tank at the sealing means, the stirring operation will not be affected.

Moreover, since the pressure in the space between the stirring chamber and the motor chamber is approximately constant, the amount of liquid flowing through the sealing means due to the pressure difference is extremely small.

〔Example〕

Next, an embodiment embodying the present invention will be described with reference to the attached drawings to provide an understanding of the present invention.

Here, FIG. 1 is a side sectional view of a stirring device according to an embodiment of the present invention.

As shown in FIG. 1, a stirring device 10 according to an embodiment of the present invention includes a stirring chamber 1 constituting a lower stirring tank.
1, a motor chamber 12 constituting an upper stirring tank, a stirring blade 13 which is an example of a stirring tool disposed in the stirring chamber 11, an induction motor 14 disposed in the motor chamber 12, and A drive shaft 15 that connects an induction motor (hereinafter referred to as a motor) 14 and a stirring blade 13
It consists of the following: and its auxiliary equipment. These will be explained in detail below.

The stirring chamber 11 constituting the stirring tank and the motor chamber 12 constituting the lower stirring tank are divided by a partition wall 16, and these stirring chamber 11 and motor chamber 12 are made into corrosion-resistant pressure vessels and are placed in a predetermined manner. The structure is such that it can withstand pressure or vacuum.

A discharge valve 17 is provided at the bottom of the stirring chamber 11, and is configured to discharge the raw material after stirring, and the stirring chamber 11 as a whole is mounted on a pedestal 18.

Electric motor 14 arranged in the electric motor room 12
This is a cage-type electric motor, and the core and windings are treated for corrosion resistance. That is, the windings of the motor are made of Teflon or ceramic insulated wire, the core is corrosion-resistant plated or painted, and the rotor 1 is
9 surface is coated with corrosion-resistant material.

and the motor shaft 20 and the motor casing 2
1 is made of stainless steel, and its bearing 22,
23 is made of ceramic or carbon-based material that can be used in liquid and does not corrode. The windings of the stator 24 of the motor 14 are not connected inside the motor room 12, and the winding start and end of each phase are all pulled out outside the tank and connected at a terminal 25 provided outside the tank. .

The electric motor 14 is a multi-polar motor (usually 8 or more poles), and its driving power source is driven at a frequency lower than the commercial frequency, and the rotation speed is about 200 to 400 rpm, depending on the raw material being used. It has rotating stirring blades at the bottom. The reason why the electric motor rotates at such a low speed is that it is extremely difficult to manufacture a reducer that can be used in a vacuum or in any liquid, and even if it were manufactured, foreign substances would be generated due to wear of the reducer. This is because there is a risk of contamination of the stirring chamber, and furthermore, it is possible to obtain the specified rotational speed and rotational force by using an electric motor with a low rated frequency and a large number of poles without using a reducer. It is.

The shaft 20 of the electric motor 14 and the drive shaft 15 of the stirring blade 13 are connected by a coupling coupling 27.

The shaft 20 has a bearing 2 fixed on the partition wall 16.
Further, a sealing gasket 29 is provided on the upper part of the bearing 28 to temporarily seal the motor chamber 12 and the stirring chamber 11.

Further, a small blade 30 is attached to the shaft 20, and circulates the liquid in the motor chamber 12 to move the motor 1.
4 and bearings are cooled.

A lid 31 that can be opened and closed is attached to the top of the electric motor 12.
A detector 32 for detecting the liquid level in the tank and a replenishment tank 33 for the liquid are attached. This liquid is in the motor compartment 12
The stirring chamber 1 is filled with the same liquid as that filled in the stirring chamber 1.
Use the liquid used for the raw material to be stirred in 1, or the liquid that will not affect the raw material even if purchased.

Stop valves 34 and 35 are connected to the upper and lower parts of the replenishment tank 33, and
and a pressure equalizing pipe 36 connecting the electric motor chamber 12 and the stirring chamber 11, respectively. This pressure equalizing pipe 3
The other end of the stirring chamber 11 and the motor chamber 12 can be vacuumed or pressurized to a predetermined pressure by being connected to a pump (not shown).

Note that there is a raw material inlet 3 at the upper side of the stirring chamber 11.
7 and an inspection port 38 are provided, and 40 in the figure is provided.
indicates raw materials (solid and liquid or liquid and other liquid), and 41 indicates the liquid filled in the motor chamber 12.

Next, the operation of the stirring device 10 according to the above embodiment will be explained in more detail.

First, after inputting a predetermined raw material from the raw material input port 37, a pump (not shown) is driven to bring the inside of the stirring chamber 11 to a predetermined pressure. At this time, the pressure inside the motor chamber 12 is also the same, but the pressure applied to the lower sealing gasket 29 is only the head pressure of the liquid contained in the motor chamber 12.

It is assumed that the stirring chamber 11 and the motor chamber 12 are completely sealed.

Next, when the electric motor 14 is driven to rotate, the stirring blade 1
3 starts to rotate, but after repeated use, liquid may leak from the sealing gasket 29 of the partition wall 16 and enter the stirring chamber 11 at the bottom.
Even in this case, there is no particular problem because the liquid is a liquid or solvent that will not affect the raw material even if mixed into the raw material.

On the other hand, when the liquid moves to the lower part, the amount of liquid in the upper motor chamber 12 decreases, so this is detected by the detector 32, and the lower stop valve 34 is opened to replenish the liquid from the replenishment tank 33 to the required level. do.
This control can be performed automatically, or it can be performed manually if the amount of liquid leaking to the bottom is extremely small.

The raw material stirred in this manner is discharged by opening the lower discharge valve 17.

The motor chamber 12 is provided with a water jacket structure 39, so that the heat accompanying the rotation of the motor can be transferred to the liquid circulating inside and then released to the outside.

〔Effect of the invention〕

As is clear from the above description, in the stirring device according to the present invention, the stirring tool is directly driven by an electric motor, so that efficient stirring is possible.

In addition, since the electric motor is sealed and placed inside the electric motor chamber that makes up the stirring tank, unlike the conventional case where the electric motor is placed outside, there is no leakage from the bearings, and it can be used in a vacuum or under pressure. Stirring became possible.

The motor chamber where the electric motor is installed is separate from the stirring chamber, but the motor chamber is filled with a solvent for the raw materials or a liquid that does not cause any problems even if mixed into the raw materials, so there is no risk of leakage from the bearings. However, there is no problem with stirring work.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a stirring device according to an embodiment of the present invention. [Explanation of symbols], 10... Stirring device, 11...
Stirring chamber, 12...motor room, 13...stirring blade,
14... Electric motor, 15... Drive shaft, 16... Partition wall, 17... Discharge valve, 18... Mount.

Claims (1)

[Claims] 1. A hermetically sealed stirring tank is divided into a stirring chamber in which raw materials are introduced and stirred, and a motor chamber in which a motor is installed to rotate a stirring tool in the stirring chamber via a drive shaft. The electric motor chamber is filled with a solvent used for stirring or a liquid that can be mixed with the raw materials, and the pressure in the space between the stirring chamber and the electric motor chamber is approximately constant. stirring device. 2 The motor is a cage-type multipolar induction motor,
The stirring device according to claim 1, wherein the rated frequency is lower than the commercial frequency. 3. The fixed windings of the motor are made of Teflon or ceramic insulated wires that are resistant to chemicals and heat, and the windings of each phase that can be used in liquid are connected outside the tank. The stirring device according to item 1.