JP2000045990A - Motor integral type thrust bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the bearing structure and reduce the device size and number of parts and thereby to reduce cost by providing a mechanism for generating pressure on at least one of either the upper or lower end of the rotor of a motor and constructing the thrust bearing with the rotor end and the housing of at least one of the impellers. SOLUTION: A thrust groove 7 for generating pressure on a ring 1 for a thrust bearing is made. A motor rotor is formed by fixing a rotor iron core with the ring 1 from up and down. A double pressed dynamic pressure thrust bearing is made by inserting the motor rotor with an impeller housing 3 with a clearance h. In the case where a thrust force generated by a lower side impeller 8 is greater than a thrust force generated by an upper side impeller 8 and thus double pressed thrust bearing is not required, the ring 1 having the thrust groove 7 for generating pressure is disposed on only one side of a rotor iron core 2. Further, a dynamic pressure thrust bearing is formed with the ring 1 and an impeller housing 3 opposed thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor-integrated thrust bearing device such as a centrifugal compressor and an expansion turbine.

[0002]

2. Description of the Related Art A conventional motor-integrated thrust bearing device of this type, for example, a thrust bearing device in a rotating machine having impellers at both ends of a motor is configured as shown in FIG. 1 is an overall sectional view mainly showing a thrust bearing device in a rotating machine having an impeller at both ends of a conventionally used motor.

In FIG. 10, impellers 8 at both ends of a rotating shaft 9 of a motor apply a static pressure of passing gas to an impeller back plate 10.
10 and the impeller housing 3, and a pressure difference generates a thrust force in the direction of the arrow in FIG. Therefore, in this rotating machine, since it is necessary to support the thrust force in two directions by the thrust bearing, it is necessary to constitute a double-pressing thrust bearing for supporting the thrust plate 6 from both sides, and the bearing portion has a dynamic thrust bearing. In general, when a pressurized gas bearing is used, the bearing components must have a structure that is as simple as possible and easy to obtain accuracy. Therefore, there are problems such as an increase in the number of parts, an increase in cost, and an increase in the size of the machine.

[0004] In order to reduce the size of the thrust bearing, there is a configuration in which the thrust force is integrated in one direction and the thrust bearing is held in one direction. The method of integrating the thrust force in one direction is as follows.
Since the fluid thrust force is generated by the pressure acting on the impeller back plate portion 10, as a conventional first embodiment, a seal is provided between the impeller back plate portion 10 and the impeller housing 3 as shown in FIG. There is a method of reducing the thrust force by adopting a structure provided with the device 11 and reducing the area of the impeller back plate on which pressure acts.

[0005] In addition to the above method, Japanese Patent Laid-Open No.
There is a method proposed in Japanese Patent Application Publication No. 5984, which discloses a gas bearing-supported expansion turbine having a turbine impeller on one side and a blower impeller on the other end, and a flow path between a blower diffuser outlet and a blower impeller back plate. This is a method of increasing the thrust force generated on the blower side, reducing the difference in thrust force with the turbine side, and supporting the thrust force in a well-balanced manner.

Further, as a second conventional embodiment,
In particular, in the case of a vertical installation, there is a method of installing the lower thrust force generated by the impeller below so that the gravity and the thrust force are in the same direction.

[0007]

However, according to the above-described first embodiment, the size can be reduced, but the impeller and the casing must be machined, which makes the machining difficult and makes the machining procedure difficult. Increase in cost is an issue due to the increase in the number of parts and the number of parts.

According to a second conventional embodiment,
Because the vertical relationship of the impeller is determined, the conventional method may not be adopted due to various problems.For example, when a rotary machine having a compressor impeller and a turbine impeller at both ends of a motor is used in a vertical type, In general, the pressure on the compressor side is higher than the pressure on the turbine side, so the compressor impeller and turbine impeller position the compressor in the lower part and the turbine in the upper part, so that the thrust force is directed downward in the same vertical direction as gravity. As a result, it is possible to reduce the size of the thrust bearing.However, if condensed water is generated in the turbine, install the turbine at the bottom as a method of collecting condensed water and drop the condensed water by gravity. Since the method of collecting and recovering is simple without using a special condensed water recovery mechanism or the like, it is necessary to install the turbine at the lower part. In other words, there is a problem that the conventional downsizing method cannot be adopted because the gravity and the thrust force are in opposite directions.

The present invention has been made in view of the foregoing, and has as its object to simplify the thrust bearing structure to reduce the size of the machine, reduce the number of parts, and thereby reduce the cost.

[0010]

SUMMARY OF THE INVENTION A motor-integrated thrust bearing device according to the present invention has been made in order to solve the above-mentioned problem. A mechanism for generating pressure at one end is formed, and a thrust bearing is formed by the rotor end and both impellers or the housing of one of the impellers.

In the above-mentioned rotary machine, a mechanism for generating pressure in at least one housing of the impeller is formed, and a rotor end of a motor on a side facing the housing that forms the mechanism for generating pressure, and a pressure generating mechanism. The thrust bearing is constituted by a housing having a mechanism for causing the thrust bearing.

In the above-mentioned rotary machine, an impeller housing includes a mechanism for generating pressure at one end of a stator of a motor, and a mechanism for generating pressure at the stator end and at a side opposite to the stator end. The thrust plate is sandwiched between the two to constitute a double presser thrust bearing.

In the rotary machine, a thrust plate having a mechanism for generating pressure is sandwiched between one end of a stator of a motor and a housing of an impeller opposed to the end of the stator, thereby forming a double holding thrust bearing. Make up.

Further, in a rotating machine having an impeller at both ends of the motor, a mechanism for generating pressure on one of the surfaces where the one end of the stator of the motor and the thrust plate meet is constituted, and the thrust bearing is formed by the stator of the motor and the thrust plate. It constitutes.

In the motor-integrated thrust bearing device according to the present invention, the thrust bearing is constituted by the rotor or the stator of the motor and the housing of the impeller in a rotating machine having impellers at both ends of the motor. Need not be configured separately from the motor, the size of the machine can be reduced, the number of parts can be reduced, and the cost can be reduced accordingly.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a motor-integrated thrust bearing device according to the present invention will be described below with reference to FIGS.

FIGS. 1 and 2 show a first embodiment. FIG. 1 is an overall sectional view, and FIG. 2 is an exploded perspective view of a structure of a thrust bearing portion. In FIGS. A thrust groove 7 for generating pressure in the ring 1 for use,
The rotor core 2 and the ring 1 are fixed by using a ring 1 to fix the rotor core 2 made of laminated silicon steel sheets and the like from above and below.
As a motor rotor, and the rotor is sandwiched between the impeller housing 3 with a clearance h,
A double press dynamic pressure thrust bearing is configured.

Normally, the rotor core 2 and the stator core 4 have the same length, and the stator core 4 has the stator winding 5 attached thereto. The spacer must be larger than the height d of the winding 5 or between the thrust bearing ring 1 and the rotor core 2 so as to be larger than the height d. This is a value determined by design.

FIG. 3 is an overall sectional view showing another embodiment of the first embodiment. For example, the lower impeller 8
If the thrust force generated by the thrust bearing 7 is larger than the thrust force generated by the upper impeller 8 and no double pressing thrust bearing is required, the thrust bearing ring 1 in which the thrust groove 7 for generating pressure is produced is attached to the rotor core 2. Installed on one side only,
The ring 1 and the impeller housing 3 facing the ring 1 constitute a dynamic pressure thrust bearing.

The thickness D of the thrust bearing ring 1 is made larger than the height d of the stator winding 5 or the height D is made larger than the height d between the thrust bearing ring 1 and the rotor core 2. Insert the spacer.

4 and 5 show a second embodiment of the present invention. FIG. 4 is an overall sectional view, and FIG. 5 is an overall sectional view showing another embodiment of the second embodiment. In the first embodiment, the thrust groove 7 for generating pressure is formed in the thrust bearing ring 1 in the first embodiment, but the thrust groove 7 for generating pressure is formed in the thrust groove 7 in the second embodiment. It is formed on the impeller housing 3 facing the bearing ring 1 to constitute a dynamic pressure thrust bearing.

FIGS. 6 and 7 show a third embodiment of the present invention. FIG. 6 is an overall sectional view, and FIG. 7 is an exploded perspective view of the structure of a thrust bearing.
A thrust groove 7 for generating pressure is formed on one end of a stator core 4 formed by laminating silicon steel plates and the like, and the stator core 4 and the ring 1 are integrally formed to constitute a motor stator. And a thrust groove 7 for generating pressure, on the side opposite to the stator and the thrust bearing ring 1.
The thrust plate 6 is sandwiched between the impeller housings 3 prepared above, with a clearance h, to form a double-pressing dynamic pressure thrust bearing.

The thickness D of the thrust bearing ring 1 is made larger than the thickness d of the stator winding 5 or the height d is made larger than the height d between the thrust bearing ring 1 and the rotor core 2. Insert the spacer. And the gap h
Is a value determined by the design of the bearing.

FIG. 8 is an overall sectional view showing a fourth embodiment of the present invention. In the third embodiment, the thrust groove 7 for generating pressure is formed by the thrust bearing ring 1 and the ring 1. In the fourth embodiment, thrust grooves 7 for generating pressure are formed on both sides of the thrust plate 6 to constitute a dynamic pressure thrust bearing. .

FIG. 9 is an overall sectional view showing a fifth embodiment of the present invention, in which a thrust bearing ring 1 is installed at one end of a stator core 4 so that the stator core 4 and the ring 1 have an integral structure. A thrust groove 7 for generating a pressure on one of the surfaces where the ring 1 and the thrust plate 6 are joined, and a thrust bearing is constituted by the ring 1 and the thrust plate 6.

With such a configuration, the thrust bearing is integrated with the motor rotor or the stator, so that the size of the thrust bearing can be reduced, and the number of parts can be reduced due to the simplification of the structure.

[0027]

As described above, according to the present invention,
In a rotating machine having an impeller at both ends of a motor, a thrust bearing is configured by a rotor or a stator of the motor and a housing of the impeller.Thus, it is not necessary to configure the thrust bearing separately from the motor. It is possible to reduce the cost and thereby the cost.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a motor-integrated thrust bearing device of the present invention.
1 is an overall sectional view showing an embodiment of the present invention.

FIG. 2 is a first view of a motor-integrated thrust bearing device according to the present invention;
It is an exploded perspective view of the thrust bearing part composition showing the embodiment.

FIG. 3 is a first view of a motor-integrated thrust bearing device according to the present invention;
FIG. 15 is an overall sectional view showing another embodiment of the embodiment.

FIG. 4 shows a second embodiment of the motor-integrated thrust bearing device of the present invention.
1 is an overall sectional view showing an embodiment of the present invention.

FIG. 5 is a second view of the motor-integrated thrust bearing device of the present invention.
FIG. 13 is an overall cross-sectional view showing another embodiment of the embodiment.

FIG. 6 shows a third embodiment of the motor-integrated thrust bearing device of the present invention.
1 is an overall sectional view showing an embodiment of the present invention.

FIG. 7 is an exploded perspective view of a configuration of a thrust bearing portion showing a third embodiment of a motor-integrated thrust bearing device according to the present invention.

FIG. 8 shows a fourth embodiment of the motor-integrated thrust bearing device of the present invention.
1 is an overall sectional view showing an embodiment of the present invention.

FIG. 9 shows a fifth embodiment of the motor-integrated thrust bearing device of the present invention.
1 is an overall sectional view showing an embodiment of the present invention.

FIG. 10 is an overall sectional view mainly showing a thrust bearing device in a rotary machine having impellers at both ends of a conventional motor.

FIG. 11 shows a conventional thrust force reduced to 1
It is principal part sectional drawing which shows embodiment which collects in a direction and reduces a thrust bearing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thrust bearing ring 2 Rotor core 3 Impeller housing 4 Stator core 5 Stator winding 6 Thrust plate 7 Thrust groove 8 Impeller 9 Rotary shaft 10 Impeller back plate 11 Sealing device

Claims (5)

[Claims] In a rotating machine having an impeller at both ends of a motor, a mechanism for generating pressure at upper and lower ends of a motor rotor or at one end thereof is constituted, and the rotor end and both impellers or one of the impellers are formed. A thrust bearing device integrated with a motor, wherein a thrust bearing is constituted by a housing of an impeller. 2. A rotating machine having an impeller at both ends of a motor, wherein a mechanism for generating pressure in at least one housing of the impeller is formed, and a motor facing the housing which forms the mechanism for generating pressure is provided. Rotor end,
A thrust bearing device integrated with a motor, wherein a thrust bearing is constituted by a housing having a mechanism for generating pressure. 3. A rotary machine having an impeller at both ends of a motor, a mechanism for generating pressure at one end of a stator of the motor, and a mechanism for generating pressure at the stator end and a side facing the stator end. The thrust plate is sandwiched between the housings of the impeller having the above structure to form a double-holding thrust bearing. 4. In a rotary machine having an impeller at both ends of a motor, a thrust plate having a mechanism for generating pressure on both sides is sandwiched between one end of a stator of the motor and a housing of the impeller opposed to the stator end. A motor-integrated thrust bearing device, comprising a double presser thrust bearing. 5. A rotary machine having an impeller at both ends of a motor, wherein a mechanism for generating a pressure is applied to one end of a stator of the motor or one of surfaces on which a thrust plate is fitted, and a thrust is generated by the stator of the motor and the thrust plate. A motor-integrated thrust bearing device comprising a bearing.