JP2878926B2 - Bearing device for canned motor and canned motor provided with the bearing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for a canned motor and a canned motor provided with the bearing device, and more particularly to a bearing device for a canned motor comprising a cartridge type bearing and a canned motor provided with the bearing device.

[0002]

2. Description of the Related Art Many canned motor pumps self-circulate a handling liquid and lubricate the bearings with the handling liquid. The bearing of the canned motor is generally made of plain metal and is composed of two radial metals that support the rotor on both sides and two thrust metals that support a thrust load in both axial directions. In order for these components to function sufficiently, the dimensional accuracy of each component as well as the dimensional accuracy between components (concentricity, perpendicularity to an axis, end play, etc.) is required. For that purpose, it is necessary to make the structure and the shape easy to obtain the precision, and to easily secure the precision at the time of processing and assembly.

Next, an example of a conventional canned motor bearing device will be described with reference to FIGS. 6 and 7. FIG. The rotor 60 of the canned motor is generally rotatably supported by radial bearings 62 and 63 on both sides of the rotor.
Thrust disks 64 and 65 are fixed to both sides of the main shaft 61 of the rotor 60, respectively.
Nos. 4 and 65 have rotation-side thrust metals 66 and 67, respectively.
Has been fixed. On the other hand, a fixed-side thrust metal 69 is fixed to the motor frame 68, and the rotating-side thrust metal 66 faces the fixed-side thrust metal 69. Further, the rotation-side thrust metal 67 of the thrust disk 65 faces the end surface of the radial bearing 63 held in the bearing housing 70.

[0004]

Depending on the quality of the liquid handled in the above-mentioned canned motor pump, there is a liquid containing slurry, and in order to prevent the slurry from entering the bearing, the sliding portion of the radial bearing is required. The smaller the clearance, the better. That is, the smaller the clearance of the radial bearing, the higher the pressure of the sliding contact surface of the bearing and the more difficult the slurry to enter. In order to reduce the clearance of the sliding part of the bearing, it is necessary to assemble two radial bearings concentrically. However, to maintain this concentricity requires precision machining, which is a factor of cost increase. Was.

[0005] Further, with regard to the thrust bearing, if the end play in the axial direction is large, slurry tends to enter when the operation is stopped, and the thrust metal may be damaged by the impact during transportation, so that an optimum end play is required. .

In the above-described conventional canned motor, in order to ensure the optimal end play, FIG.
7A shows the dimension A on the rotor side (the distance between the end faces of the rotating thrust metals 66 and 67) and the dimension G on the stator side shown in FIG. It is necessary to accurately determine the distance between the end faces 63. In this case, in order to determine the A dimension, it is necessary to accurately determine the dimensions of a plurality of components that determine the A dimension as shown in FIG. On the other hand, in order to determine the G dimension, it is necessary to accurately determine the dimensions of a plurality of components that determine the G dimension as shown in FIG.

As a result, the conventional canned motor has a problem that machining is very difficult because the spindle 61, which is a very long part, requires high dimensional accuracy.

Further, in the conventional canned motor,
Since high dimensional accuracy is required for the stator, which is a very long part, there has been a problem that it is very difficult to manufacture the stator including processing and the like.

Further, since the thrust bearings are provided at both ends of the main shaft, the end play can be recognized only when the rotor is incorporated into the stator. Therefore, if the end play is not appropriate, the end play must be reassembled many times. There was a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to ensure axial end play between thrust sliding members extremely easily, and to provide bearing mounting portions on both sides of a motor. It is an object of the present invention to provide a bearing device for a canned motor capable of absorbing deviations in concentricity and perpendicularity, dimensional errors in fitting, and the like, and a canned motor provided with the bearing device.

[0011]

In order to achieve the above-mentioned object, a bearing device for a canned motor according to the present invention comprises a radial bearing for rotatably supporting a rotor and a thrust load in both axial directions.
In a bearing device for a canned motor provided with a thrust bearing for supporting a bearing, a bearing housing holding a radial bearing is detachably provided on the motor, and fixed-side thrust sliding members having sliding surfaces are provided on both sides of the bearing housing. A rotating thrust sliding member is provided on the rotor so as to sandwich the fixed thrust sliding member, and the bearing housing is radially fixed to a motor frame via an elastic body. It is.

[0012]

According to the present invention having the above-described structure, since a component that is long in the axial direction such as the main shaft and the stator does not require processing accuracy, it is extremely easy to secure the end play. Further, since the rotor excluding the impeller can be assembled in advance, it is extremely easy to adjust the axial end play between the thrust sliding members. Since the end play adjustment is easy, the end play can be reduced to “0 (zero)” without limit, and it is possible to prevent a metal crack due to an impact during transportation and a foreign substance from entering a sliding portion.

Further, according to the present invention, since the bearing housing is fixed via an elastic body such as an O-ring, the elastic body may be out of alignment and squareness of the bearing mounting portions on both sides of the motor. It is a structure that absorbs dimensional errors and the like of fitting of the spigot part, and it is not necessary to accurately obtain the processing accuracy of each part.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a bearing device for a canned motor according to the present invention and a canned motor provided with the bearing device will be described below with reference to FIGS. FIG. 1 is a sectional view showing an all circumferential flow type in-line pump provided with a bearing device for a canned motor according to the present invention. The in-line pump shown in this embodiment includes a suction-side casing 1, a discharge-side casing 5,
An outer cylinder 9 for connecting the suction side casing 1 and the discharge side casing 5 is provided. The suction side casing 1 and the discharge side casing 5 are formed by deep drawing a steel plate such as stainless steel by pressing. The suction-side casing 1, the outer cylinder 9, and the discharge-side casing 5 are each provided with a flange 1 extending outward at an outer peripheral portion of an end on the opening side.
a, 9a, 9b, 5a. Then, the suction side casing 1 and the outer cylinder 9 are clamped by adjacent flanges 1a, 9a by casting flanges 20, 20, such as cast iron, and fastened by bolts 45.
They are connected together. Similarly, the discharge side casing 5 and the outer cylinder 9 are integrally connected by mutually adjoining flange portions 5a and 9b being sandwiched by flanges 21 and 21 made of cast iron or the like and tightened by bolts 45. Have been. The suction-side casing 1, the discharge-side casing 5, and the outer cylinder 9 constitute a sheet metal pump casing, and a canned motor 22 is provided in the pump casing.

The suction side casing 1 includes a main body 2 on a truncated cone, and a cylindrical suction nozzle 3 extending from the main body 2 to the suction side. Similarly to the suction-side casing 1, the discharge-side casing 5 also has a truncated-cone-shaped main body 6 and a cylindrical discharge nozzle 7 extending from the main body 6 to the suction side. . The discharge side casing 5 and the suction side casing 1 are formed in exactly the same size and the same shape.

On the other hand, an inner casing 10 is provided inside the suction side casing 1, and this inner casing 10
Is composed of a container-shaped main body 11 and a cylindrical suction side 12 extending from the main body 11 to the suction side. A guide device 13 forming a guide vane or a volute is provided inside the main body 11 of the inner casing 10.
Is installed. The guide device 13 has a spigot fitting portion, and the spigot fitting portion is fitted to the motor frame 23 of the canned motor 22. This canned motor 2
The second motor frame 23 has high rigidity, and the guide device 13 is supported by the motor frame 23.
As a result, the inner casing 10 is supported by the motor frame 23 of the can motor 22 having high rigidity. One end of the suction side portion 12 of the inner casing 10 extends to the vicinity of the suction nozzle 3. In addition, a seal member 14 is interposed in a gap between the end of the suction side portion 12 of the inner casing 10 and the suction nozzle 3 of the suction side casing 1, and the seal member 14 allows the suction side (low pressure side) to be discharged. Side (high pressure side) is sealed.

An impeller 15 is housed inside the inner casing 10, and the impeller 15
Is fixed and supported on the main shaft 16 of the main body. A turning prevention plate 18 is fixed inside the suction side portion 12 of the inner casing 10. A liner ring 19 is disposed adjacent to the main body 11 and the suction side 12 of the inner casing 10, and the liner ring 19 and the edge 1 of the impeller 15 are provided.
A slight clearance is formed between the gap 5a. Further, a suction flange 48 and a discharge flange 49 are fixed to the suction nozzle 3 and the discharge nozzle 7 via intermediate rings 46, 46, respectively.

The motor frame 23 of the canned motor 22 has a substantially cylindrical frame outer shell 24 and frame side plates 25, 2 provided at both side openings of the frame outer shell 24.
6 is comprised. The frame outer shell 24 has a plurality of ribs 24a radially formed on its outer peripheral portion along the axial direction. The plurality of ribs 24a are formed integrally with the outer frame 24 of the motor frame by press molding, and the outer surfaces of the ribs 24a are fitted to the inner peripheral surface of the outer cylinder 9 of the pump casing. Both parts are joined and integrated by spot welding or the like.

In the motor frame 23, the stator 2
7 and a rotor 28 are provided. The rotor 28 is supported by the main shaft 16, and a cylindrical can 29 is fitted inside the stator 27. Also,
A radial bearing 30 is provided on the frame side plate 25, and the radial bearing 30 rotatably supports a shaft sleeve 31 fitted to the main shaft 16.

A bearing housing 32 is detachably provided on the frame side plate 26, and an O-ring 40 made of an elastic material is interposed between the bearing housing 32 and the frame side plate 26. The fixing between the bearing housing 32 and the frame side plate 26 is performed by a loose fit spigot and an O-ring 40 made of an elastic material. At this time, since the outer diameter of the bearing housing 32 is larger than the inner diameter of the can 29, the O-ring 40
Has a large friction torque, and the effect of preventing the bearing housing 32 from rotating is large. The bearing housing 32 is prevented from coming off in the axial direction from the frame side plate 26 by the holding plate 41. An elastic member 42 is interposed in the axial gap between the bearing housing 32 and the frame side plate 26. The bearing housing 32 holds a radial bearing 33 and a fixed-side thrust metal 34, respectively. The radial bearing 33 is configured to rotatably support a shaft sleeve 35 fitted to the main shaft 16.

On the other hand, two thrust disks 36 and 37 are fixed to the discharge side end of the main shaft 16 so as to sandwich the bearing housing 32. The thrust disk 36 constitutes a fixed-side thrust sliding member. Radial bearing 3
3 is provided with a rotating-side thrust metal 38 facing the end face,
The thrust disk 37 is the fixed-side thrust metal 34.
And a rotation-side thrust metal 39 opposed to the above.

In this embodiment, in order to obtain the optimum end play (e), the rotor side a shown in FIG.
It is necessary to obtain the dimensions, g dimensions on the stator side shown in FIG. In the present embodiment, the main shaft 16, which is a large part as compared with the conventional example, does not need dimensional accuracy, and all the parts that require dimensional accuracy have small dimensions, so that the dimension a is extremely easy to come out. On the other hand, on the stator side, the number of components requiring dimensional accuracy is small, and further, the accuracy of the axial dimension of the stator is not required, so that end play (e) can be secured very easily. Has become.

In this embodiment, as shown in FIG. 4, it is possible to assemble the rotating body R excluding the impeller, that is, to assemble the small parts on one side of the motor. Most of the cartridge structure
It is configured to be inserted into the spigot portion I of the stator via the O-ring 40. As a result of the cartridge structure, the end play (e) can be easily adjusted before the cartridge is inserted into the stator. Also, the spigot I
Since the O-ring 40 is fitted in the bearing housing 32 and the radial position of the bearing housing 32 is fixed, the concentricity and perpendicularity of the bearing mounting portions on both sides of the motor and the dimensional error in fitting the spigot portion are reduced. The structure is such that the O-ring 40 absorbs it, and does not require machining accuracy of the spigot portion of the stator and the bearing housing.

Next, another embodiment of the present invention will be described with reference to FIG. 5, components having the same functions and functions as those of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, the bearing device including the thrust bearing is substantially the same as the embodiment shown in FIG. 1, but the bearing device located on the opposite side across the rotor is different.
That is, the bearing housing 52 is detachably provided on the frame side plate 25. An O-ring 53 made of an elastic material is interposed between the bearing housing 52 and the frame side plate 25. Grooves 52a, 25a for accommodating the O-ring 53 are formed in both the bearing housing 52 and the frame side plate 25, and thereby the bearing housing 52 is prevented from coming off. The bearing housing 52 holds the radial bearing 30.

In order to completely prevent the bearing housing 52 from coming off, a collar 54 is fixed to the main shaft 16. In the present embodiment, the bearing housings 32, 52 provided at both shaft ends of the main shaft 16 are supported by the frame side plates 25, 26 in a floating state. Of the concentricity and dimensional error of the bearing mounting part can be absorbed.

In this embodiment, the inner casing 10 is constituted by a suction side partition plate 11a and a guide device 12a. A member 55 for preventing slurry from entering the bearing is provided on the non-load side of the main shaft 16.

In the embodiment shown in FIGS. 1 and 5,
Although the radial bearing 33 and the fixed-side thrust metal 34 are provided as the fixed-side thrust sliding members, the radial bearing 33 is extended without providing the fixed-side thrust metal 34, and the end surface of the radial bearing 33 is directly rotated. 39 may be brought into sliding contact.

[0029]

As described above, according to the present invention, it is extremely easy to secure the end play because no processing accuracy is required for components that are long in the axial direction such as the main shaft and the stator. Further, since the rotor excluding the impeller can be assembled in advance, it is extremely easy to adjust the axial end play between the thrust sliding members. Since the end play adjustment is easy, the end play can be set to “0 (zero)” without limit, and it is possible to prevent metal breakage due to impact during transportation and entry of foreign matter into the sliding portion.

Further, according to the present invention, since the bearing housing is fixed via an elastic body such as an O-ring, the elastic body may be out of concentricity and squareness of the bearing mounting portions on both sides of the motor, or may have an inlay. It is a structure that absorbs dimensional errors and the like of fitting of parts, and it is not necessary to accurately obtain the processing accuracy of each part.

[Brief description of the drawings]

FIG. 1 is a sectional view of an in-line pump provided with a bearing device for a canned motor according to the present invention.

FIG. 2 is a sectional view of a bearing device for a canned motor according to the present invention.

FIG. 3 shows a rotor side (FIG. 3 (a)) and a stator side (FIG. 3 (b)) in the canned motor bearing device according to the present invention.
It is explanatory drawing which respectively shows.

FIG. 4 is an explanatory view showing a method of assembling a bearing device for a canned motor according to the present invention.

FIG. 5 is a sectional view showing another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a conventional canned motor bearing device.

FIG. 7 is an explanatory view showing a rotor side (FIG. 7 (a)) and a stator side (FIG. 7 (b)) in a conventional canned motor bearing device.

[Explanation of symbols]

 Reference Signs List 1 suction side casing 3 suction nozzle 5 discharge side casing 7 discharge nozzle 9 outer cylinder 10 inner casing 13 guide device 14 seal member 15 impeller 16 main shaft 22 canned motor 23 motor frame 24 motor frame outer body 25, 26 frame side plate 27 stator 28 Rotor 32,52 Bearing housing 40,53 O-ring

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-69439 (JP, A) JP-A 55-32627 (JP, U) JP-A 2-79155 (JP, U) (58) Investigation Field (Int.Cl. ⁶ , DB name) H02K 5/132 H02K 5/167

Claims (5)

(57) [Claims] 1. A radial bearing for rotatably supporting a rotor ;
In a bearing device for a canned motor having a thrust bearing for supporting a thrust load in both axial directions, a bearing housing holding a radial bearing is detachably provided on the motor, and a fixed side having sliding surfaces on both sides of the bearing housing. A thrust sliding member is provided, and a rotating-side thrust sliding member is provided on the rotor so as to sandwich the fixed-side thrust sliding member,
A bearing device for a canned motor, wherein the bearing housing is fixed in a radial direction to a motor frame via an elastic body. 2. The canned motor bearing device according to claim 1, wherein an outer diameter of said bearing housing is larger than a can inner diameter of said motor. 3. The bearing device for a canned motor according to claim 1, wherein said bearing housing is held down by a holding plate to prevent the bearing housing from coming off in the axial direction. 4. The bearing device for a canned motor according to claim 1, wherein an elastic body is interposed in an axial gap between the bearing housing and the motor frame. 5. A bearing device according to any one of the rotor interposed therebetween claims 1 to 4 to 1 side of the motor is provided, wherein the kite is provided a bearing housing holding the radial bearing on the other side And canned motor.