JP2543498Y2 - Canned motor pump - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in the internal structure of a canned motor, and more particularly, to a canned motor pump using the improved canned motor.

[0002]

2. Description of the Related Art Generally, in a canned motor pump, a rotor and a stator constituting a motor portion are covered with a rotor sleeve and a stator liner, respectively, so that the motor portion is liquid-tight. It is widely awarded as a pump for use in

[0003]

However, this type of conventional canned motor pump has the following drawbacks.

[0004] For example, a motor unit consisting of the induction motor,
While the rotor by a rotating magnetic field formed by the stator Ru is rotated, in this case, the conductor is present inside the rotating magnetic field (stator liner and rotor sleeve) is an eddy current is generated, to generate the energy loss. However , this energy loss is proportional to the square of the frequency of the rotating magnetic field (the drive power supply frequency f for the stator liner, the rotor sliding frequency fs for the rotor sleeve) and the conductivity λ of the conductor. For this reason, in the conventional canned motor pump, as shown in FIG. 2, the eddy current loss e (curve A) increases as the driving power supply frequency (pump rotation speed) f increases.
Rapidly increases, has been a major obstacle to the demands against the speed of the pump.

As will be described in detail later, this drawback will be described later. As can be seen from the curves B and C in FIG. 2 showing the eddy current loss in the stator liner and the rotor sleeve, respectively, as can be seen from FIG. It is caused by This loss is due to the high conductivity of the material forming the stator liner. The fact that the loss C in the rotor sleeve is negligibly small irrespective of the pump rotation speed is due to the extremely small slip frequency fs, and this loss substantially occurs in, for example, a DC brushless motor. do not do.

However, conventionally, this type of canned motor
In the motor part of the pump, is it a conductor that seals the stator?
The stator characteristics of the motor
Correct air gap (stator liner thickness and low
The stator and rotor gap, including the sleeve thickness,
To keep the rotor close to the
A technology to protect the outer peripheral surface with a ceramic material has been proposed.
(Japanese Utility Model Laid-Open No. 61-120098). This place
Air gap can be smaller,
The aforementioned problems with the data liner can be solved
I can't . From this point of view, the stator liner
It is also proposed to be composed of a mixed material, but as mentioned above
In order to reduce the air gap, ceramic materials
Must be formed thinner.
And it was difficult to put it to practical use .

Therefore, an object of the present invention is to control an induction motor.
In the canned motor pump configured as a motor part,
Stator liner to maintain proper air gap
In addition to enabling the use of ceramic materials,
Reinforced with thermosetting resin to maintain sufficient strength
And increase the pump rotation speed (power supply frequency)
Also minimizes eddy current loss and reduces motor efficiency.
Provide a canned motor pump that can be prevented
It is in .

[0008]

In order to achieve the above object,
Therefore, the canned motor pump according to the present invention is provided outside the rotor.
High-strength metal material for the rotor sleeve that covers the periphery in a liquid-tight manner
The inner peripheral part of the stator and the space part on both sides
With a stator liner in a liquid-tight manner.
A part of the pump handling liquid in the gap between the valve and the stator liner.
A can consisting of an induction motor configured to circulate
In a canned motor pump having a motor unit,
Liquid-tightly covers the inner circumference and both sides of the stator
Stator liner with electrically defective conductor ceramic material
As well as inside the stator space and stator
Fill the space between the periphery and the stator liner with thermosetting resin for reinforcement.
It is characterized by being typed .

In this case, the electrically defective conductor ceramic material
Corresponding to the stator space of the stator liner
Reinforcement backing that cooperates with reinforcing thermosetting resin
A sleeve can be provided. In addition, the stay
The ceramic material that forms the tariners has a thickness of 0.2 to
It is preferable to use a thin cylinder of 1.5 mm. Further
A canned motor pump constructed as above, when <br/> to configure and use the rotation speed of the rotor than 4000 rpm, is particularly effective.

[0010]

According to the canned motor pump of the present invention,
Maintain a proper air gap for the stator liner of the motor.
In a state of being able to be lifting, moreover by holding a sufficient strength can be formed by an electric poor conductor ceramic material, this
To prevent the occurrence of eddy currents by Les, Ru can be suppressed loss by this as much as possible. Therefore, a decrease in motor efficiency can be prevented regardless of the pump speed.

In the present invention, the ceramic material
The inner space of the stator liner and the space between the inner periphery of the stator and the stator liner are cast with thermosetting resin to ensure sufficient internal pressure resistance.
It is Ru can be. Thus, in particular large-sized canned motor pump, it is possible to sufficiently secure the pump intensity at the time of high-speed rotation.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a canned motor pump according to the present invention.

FIG. 1 shows an embodiment of a canned motor pump according to the present invention. In FIG. 1, the canned motor pump basically includes a motor unit 10 and a pump unit 12. Motor unit 10 includes a rotor 16 fixed to the rotary shaft 14, it consists of the stator 20 for being fixed to the motor casing 18, each of which rotor sleeve 2
2 and a stator liner 24 (this will be described in detail later). In addition, the rotating shaft 1
4, is supported with both sides thereof by a bearing 26, the bearing monitor 28 is provided at its free end. Pump part 1
2, the impeller 30 supported on the rotary shaft 14, Ru is a pump casing 32 which accommodates this. In such a configuration, the three-phase AC power supply is connected to the terminal box 3.
To supply to the stator 20 by the power supply connection at 4
For example , a rotating magnetic field is generated in the stator 20 to rotate the rotor 16 .
It is rolling, performing <br/> pump operation by rotating the impeller 30 through the rotary shaft 14. During the operation of the pump, a part of the liquid handled by the pump is removed from the circulation pipe 36 and the motor unit 10.
(Gap between rotor sleeve 22 and stator liner 24
, Etc.), and circulates to the pump section 12, whereby the motor section 10 is cooled and the like .

However, in the present invention, the rotor sleeve 22 is made of a metal material, but preferably has a high strength, preferably SUS316L, similarly to a normal canned motor pump. On the other hand, the stator liner 24 is formed of a thin cylinder of 0.2 to 1.5 mm in thickness made of an electrically defective conductor ceramic material, preferably PSZ (partially stabilized zirconia). Then, the stator liner 24 is inserted into the space portions 38, 38 on both sides of the stator 20 and the inside of the stator inner peripheral surface 20a, and then a thermosetting resin 40 such as varnish is injected into the inserted portion, and is heated and cured. , Enhances liquid tightness and reinforces internal pressure resistance.

The stator liner 24 may be further provided with a backup sleeve 42 at a portion corresponding to both side spaces 38, 38 of the stator 20, as shown in the figure. With such a configuration, the synergistic action of the backup sleeve 42 and the thermosetting resin 40 causes the above-described liquid tightness and internal pressure resistance (here, the disadvantage that the ceramic material is extremely poor in tensile strength). ) Can be more reliably increased.

As described above, according to the present invention, since the stator liner is formed of the electrically defective conductor ceramic material, the generation of the eddy current in the stator liner is prevented, and the loss due to the eddy current is suppressed as much as possible. Therefore, a decrease in motor efficiency can be effectively suppressed especially in a region where the pump rotation speed (drive power supply frequency) is high. Further, there is an advantage that the corrosion resistance is improved. Incidentally, the effect of the present invention is that, for example, the conductivity of SUS316L is about 1.4 × 10 ⁶ moh / m, and that of PSZ is about 10 ⁻⁸ moh / m, and between 1/10 ¹⁴ moh / m.
It will be easily understood from the above differences,
Further, the loss in the rotor sleeve is ignored as described above. However, when the loss is compared with that of the stator liner of the same material, when the slip is 3%, (3/1000) ² , That is, about 10 ^-3
It becomes the size of.

Further, according to the present invention, since the stator liner is cast with a thermosetting resin between the stator space portion and the inner peripheral portion of the stator and the stator liner, the liquid tightness and the internal pressure resistance are sufficiently improved. Can be secured. On the other hand, the rotor sleeve is made of a high-strength metal material,
The strength of the rotor can be sufficiently ensured. Therefore,
In particular, even in a large-sized canned motor pump, the pump strength during high-speed rotation is sufficiently ensured.

Although the present invention has been described with reference to a preferred embodiment, the present invention is not limited to the above-described embodiment.
Many modifications can be made without departing from the spirit thereof. Further, the present invention is applied not only to a pump but also to a blower and the like, and is further applied to not only a three-phase power source but also a canned DC motor.

[0019]

As described above , according to the canned motor pump of the present invention, the rotor sleeve that covers the outer periphery of the rotor in a liquid-tight manner is formed of a high-strength metal material.
The inner circumference and the space on both sides of the stator
The rotor sleeve and the stator.
Make sure that part of the liquid handled by the pump is
Equipped with a canned motor unit consisting of an induction motor
And the canned motor pump, thereby forming an electric poor conductor ceramic material a stator liner covering the liquid-tight inner peripheral portion and both side space portion of the stator, between the status pace portion and the stator inner circumference and the stator liner The construction is made by casting with a thermosetting resin for reinforcement, so that the stator liner of the motor
With sufficient air gap and sufficient strength
Is formed by the electrically defective conductor ceramic material
This prevents the occurrence of eddy currents in the stator liner, thereby minimizing losses due to this , and also has excellent internal withstand pressure structurally.
A robust structure can be achieved . Therefore, according to the present invention,
If so , a decrease in motor efficiency can be effectively suppressed, especially even in a region where the pump rotation speed (drive power supply frequency) is high.

Further, in the present invention, since the liquid tightness and strength of the stator liner and the rotor sleeve (rotor) are sufficiently achieved, the pump strength at the time of high-speed rotation is sufficient even in a large canned motor pump. This has the advantage of being secured.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a canned motor pump according to the present invention.

FIG. 2 is a graph showing eddy current loss in a conventional canned motor pump.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Motor part 12 Pump part 14 Rotating shaft 16 Rotor 18 Motor casing 20 Stator 22 Rotor sleeve 24 Stator liner (ceramic thin cylinder) 26 Bearing 28 Bearing monitor 30 Impeller 32 Pump casing 34 Terminal box 36 Circulation pipe 38 Stator space 40 Heat Curable resin 42 Backup sleeve

Claims (4)

(57) [Scope of request for utility model registration] A rotor sleeve for covering the outer periphery of a rotor in a liquid-tight manner is formed of a high-strength metal material .
Peripheral and both side spaces are liquid-tight by stator liner
Between the rotor sleeve and the stator liner.
The pump is configured to allow a part of the pump handling liquid to flow through the gap.
A canned motor with a canned motor section consisting of an induction motor
In Taponpu, thereby forming an electric poor conductor ceramic material a stator liner covering the liquid-tight inner peripheral portion and both side space portion of the stator, reinforcing heat between the status pace portion and the stator inner circumference and the stator liner A canned motor pump characterized by casting with a curable resin. 2. A switch made of an electrically defective conductor ceramic material.
In the part corresponding to the stator space of the data liner,
Reinforcement backup file that cooperates with reinforcement thermosetting resin
2. The canned motor pump according to claim 1, further comprising a drive. 3. A ceramic material forming a stator liner.
The canned motor pump according to claim 1 or 2, comprising a thin cylinder having a thickness of 0.2 to 1.5 mm . 4. The canned motor pump according to claim 1, wherein the rotation speed of the rotor is set to 4000 rpm or more.