TW201809454A - Rotating machine and method of manufacture - Google Patents

Abstract

A method of manufacturing a rotating machine and a rotating machine are disclosed. The rotating machine comprises: at least one rotatable shaft supported on at least one bearing within a clearance bore; the bearing comprising an inner ring and an outer ring enclosing rolling elements The clearance bore comprises an inner diameter that is larger than a diameter of the outer ring of the bearing; and the rotating machine comprises a bearing biasing means for biasing the bearing in a radial direction away from a central position of the bore so as to constrain radial movement of the shaft.

Description

Rotating machinery and manufacturing method thereof

The present invention relates to a method for manufacturing a rotating machine and the like.

In order for moving parts to work accurately with each other, careful design and manufacture of rotating machinery is required. For example, radial clearances can cause tight moving parts of a rotating machine when they are too small, and poor performance when they are too large. A complex rotating machine can have many different parts, where all parts are manufactured with different clearances, and many of them interact. These tolerances can each contribute to overall performance. Because the sum of these tolerances can be large, the resulting performance can be adversely affected. This problem can cause failures in rotating machinery, in particular, failures in high-precision rotating machinery such as vacuum pumps. One solution to this is to reduce the tolerances in each component through an improved process. Although effective, this is difficult and expensive. It may be desirable to reduce the number of failures in a rotating machine without unduly increasing the cost.

A first aspect of the present invention provides a rotary machine including: at least one rotatable shaft member supported on at least one bearing in a gap hole; the bearing includes an inner ring enclosing a rolling element and a An outer ring; and the clearance hole includes an inner diameter larger than a diameter of the outer ring of the bearing; and the rotary machine includes a bearing biasing member for moving the bearing away from the hole in a radial direction A central position is offset to restrain radial movement of the shaft member. When analyzing the effects of tolerances of different components on machinery, the inventors of the present invention realized that some components have a greater impact on performance than others. In particular, the tolerance in the position of a rotatable shaft in a rotating machine has a greater impact on the overall function of that machine. In many cases, changes in the tolerance have contributed to more than 50% of the overall change. It is necessary to install the rotatable shaft member in a non-fixed manner to allow them to both rotate and move axially. During assembly, and also during use in which the shaft may expand and contract with temperature changes, axial movement is required during the axial setting of the shaft and rotor. Therefore, these shaft members are installed on the bearings, and these bearings are then installed in a clearance hole. A gap is provided between the hole and the bearing to allow axial movement. A clearance hole is substantially any cylindrical hole into which at least a part of the bearing can be inserted. The inventor of the present invention recognizes that although there may be a technical prejudice for offsetting the bearing away from the center position so that the shaft is eccentrically installed in the clearance hole, because this may seem to cause an Resistance, however, this offset would provide an improvement that allows both the position of the shaft to be more accurately predicted and more stable by reducing variations in radial position, which can occur during operation. In fact, the changes and uncertainties that are so important to the overall function in the positioning of the shaft are reduced without the need to improve the manufacturing tolerances of the bearings, bearing components and clearance holes. It should be noted that although the shaft member can be installed in the bearing with a certain gap, in general, it is installed in the bearing as an interference fitting, and the axial movement is provided between the gap hole and the bearing. In some embodiments, the bearing biasing member is configured to bias the shaft member and the gap toward a known contact position. Using a biasing member to bias a bearing away from the center of the hole in a radial direction will cause it to contact the clearance hole and constrain or hinder the shaft in any radial plane (which is any one perpendicular to the axis of the shaft) Plane). The biasing member is arranged so that its contact position is a known position, allowing the position of the shaft to be accurately predicted, and the position of the shaft can be used when designing other components of the rotary machine. In some embodiments, the rotating machine includes at least one rotor and a stator mounted on the at least one shaft, the stator includes a stator hole, and the stator hole and the clearance hole are offset relative to each other to compensate being supported on The shaft member in a radial offset position away from the center position of the clearance hole. As previously noted, by using a biasing member, the shaft is mounted non-concentrically in the clearance hole, however, its position in the other hole is more predictable. Therefore, although the variation in its position can be reduced, its overall impact on other tolerances may not always be beneficial. One way to solve this is to shift the components of the rotating machine in the same way as the mounting of the shaft in the clearance hole has been shifted. In particular, in the case where the clearance hole is offset to match the displacement of the shaft position within the clearance hole, then the radial clearance tolerance can be significantly reduced without improving the tolerance of individual components. In this manner, an improved rotating machine is provided. In some embodiments, the bearing biasing member includes one of a mechanical spring, a gas spring, and a magnetic member. The biasing member may consist of several individuals if it can provide a biasing force for biasing the bearing and thus the shaft away from a center position. Examples of this biasing member are a mechanical spring, a gas spring, and a magnetic member. The magnetic member may be a permanent magnet or it may be an electromagnet. In some embodiments, the mechanical spring includes one of a leaf spring and a coil spring, the mechanical spring extends into the clearance hole and biases the bearing against a opposing surface of the clearance hole. One effect of using a mechanical spring extending into the hole is that it can provide increased wear and deformation of the bearing, and in some embodiments, to reduce such effects, the contact surface of the bearing used to contact the mechanical spring is Shaped to correspond to one of the outer surfaces of the bearing. Providing the contact surface of the spring with a shape corresponding to the outer surface of the bearing reduces the friction and wear of the spring on the bearing and reduces this deformation. In other embodiments, the bearing includes a housing for receiving the rollable elements, the housing includes the biasing member, is composed of a flexible material, and includes the outer ring having a diameter that varies around the ring. The housing is such that one of the largest diameters of the bearing is larger than the inner diameter of the clearance hole when it is not deformed. Rather than providing a separate biasing member, in some embodiments, the biasing member can be made as a component of the bearing itself, the bearing having a housing for receiving a rollable element, the housing being made of a flexible material It is composed and has a variable diameter such that a larger diameter contacts the opposing surface of the gap hole when mounted therein and the housing is under a deforming force such that it is held in place by the flexible force. In some embodiments, the clearance hole has an alignment member for aligning the bearing biasing member with a predetermined position of one of the clearance holes. The use of the biasing member enables the bearing and therefore the shaft to be held in a fixed position within a clearance hole. Advantageously, if this position is a known position, and therefore, providing an alignment member that aligns the bearing offset member with a predetermined position of the clearance hole provides this predictability. Although the alignment member may be provided in several ways, in some embodiments, the alignment member includes an alignment recess for receiving a cooperating portion of the bearing biasing member. In some embodiments, the bearing biasing member is configured to bias the shaft toward a downward position within the clearance hole. Although the biasing member can be configured in a number of ways to bias the bearing in several directions, in some cases it is configured to bias the bearing toward a downward position within one of the clearance holes. This is particularly effective where the rotating machine system has a large machine with a heavy shaft and is configured to level the shaft. In this case, the biasing member is used to bias the shaft downward so that it can cooperate with gravity and provide a combined downward force, thereby requiring a weaker force from the biasing member to overcome the rotational imbalance. . In other embodiments, it may be advantageous to bias the bearing in one of the directions of the gas load, depending on the configuration of the rotating machine, it may be tied up or out. In the case where the gas load is significantly biased in this way, the biasing member can be caused to work together with the load on the pump to achieve a stable position of one of the shafts. In some embodiments, the rotating machine includes two parallel shaft members, each of which is supported on a bearing in a respective clearance hole, and the bearing biasing member is installed between the two clearance holes. Some rotating machines have two or more than two shaft members, each of which is mounted on a bearing. In some cases, one of the bearing biasing members disposed between the two holes and acting on the bearing of the two shaft members may be used. In this manner, a single bearing biasing member can be used to bias the bearings in each of the two shaft members. In some embodiments, the bearing biasing member extends into the two clearance holes and biases each bearing away from each other toward an outer wall of one of the respective clearance holes. In other embodiments, the bearing biasing member may be configured to bias the bearings toward each other. In this regard, the bearing biasing member may be a magnet that attracts a magnetic material of the bearing element or the bearing outer ring or a magnetic material mounted on the bearing element or the bearing outer ring. In either case, the attraction of the magnet can be used to bias the bearing. In alternative embodiments, the magnet may be mounted to repel the bearing. In either case, the bearing biasing member need not extend into the clearance hole, which reduces bearing deformation and wear. In some embodiments, the bearing biasing member is configured to bias each bearing in the same direction. It may be advantageous to bias the bearings in the same direction, in that it reduces variations in the distance between the two shaft members. In some embodiments, the rotary machine includes a plurality of bearing biasing members, which are used to bias the bearings away from a center position of the hole in a radial direction in order to restrain the radial movement of the shaft, Each of the bearing biasing members is configured such that at least one component of a biasing force exerted on the bearing by the bearing biasing member is directed toward a contact position between the bearing and one of the clearance holes. Although each bearing may be biased by a single biasing member, in some cases it may be advantageous to use two or actually multiple biasing members. In the case where these biasing members are configured such that each of them has a component of a biasing force toward a contact position of a bearing on the clearance hole, then, by having more than one biasing member, holding the shaft member is provided. A more stable configuration in one of the more predictable and non-variable positions, which more effectively offsets rotational imbalances and offsets the load from the pumped gas or liquid. In other embodiments, there may be a single biasing member that functions to contact an intermediate part of a bearing in two or more positions. The use of an intermediate part, such as a bridge part, allows a single biasing member to act on more than one point, thereby providing the desired increase in stability, and providing one of the shaft members with a more predictable and non-variable position. In some embodiments, the rotary machine further includes an axial biasing member for biasing the at least one rotatable shaft member against a plate, so that one end of the shaft member is axially fixed, and the shaft member The other end can move axially in response to thermal changes; configure the bearing biasing member with a bias strength high enough to offset the rotational imbalance, and configure the axial biasing member with relative strength, Such as to allow the shaft to respond to the axial movement of the axially biasing member. Providing a biasing member that biases the bearing away from the center position in a radial direction provides a member that has the ability to offset the rotational imbalance and the shaft has a more predictable position within the rotating machine to offset the rotational imbalance And positions with higher predictability can lead to improved performance and offset problems due to tolerances within the components forming the rotating machinery. The strength of the biasing member can be selected according to the desired characteristics. In particular, reducing the rotational imbalance not only improves performance, but also reduces noise and vibration generated by rotating machinery. In some embodiments, a radial mounting screw is provided as a radial biasing member toward one of the fixed ends of the shaft member. The radial mounting screw secures the bearing in a desired position. In some embodiments, a pad may be installed between the bearing and the screw to reduce the wear and tear of the bearing. In some embodiments, the at least one rotatable shaft is mounted on two bearings; the bearing biasing member of the bearing closest to the axially movable end is configured to be strong enough to offset or inhibit any The rotation is unbalanced and weak enough to respond to the axial biasing member allowing the axial shaft to move; and the bearing biasing member of the bearing closest to the axially fixed end is configured to be strong enough to offset or at least Suppresses any rotational imbalances. In the case where the rotatable shaft member is mounted using an axial biasing member that biases the rotating shaft member against a plate, and the shaft member is supported by two bearings, then, the bearing closest to the axial biasing member The shaft should be allowed to move axially so that it can expand and contract, and another bearing member need not provide this axial movement. Therefore, when selecting the strength of the offset member, the position of the bearing offset should be considered. One of the biasing members strong enough to effectively offset the rotational imbalance provides advantages, however, the bearing biasing member of the bearing closest to the axially movable end of the shaft should not have too high a biasing strength because it requires The shaft is allowed to move axially in response to the axial biasing member so that as it contracts after expansion, it will move back toward its previous position. One way to facilitate axial movement may be to use a low-friction coating on the bearings and / or clearance holes. Although embodiments of the present invention provide the advantages of many different types of rotating machinery, they are particularly advantageous when used in a vacuum pump. A vacuum pump is a high-precision device that requires high-precision tolerances, and changes in these tolerances can cause the pump to tighten. In particular, this configuration may be particularly advantageous where the vacuum pump system does not use lubricants and therefore requires a dry pump of very high accuracy. Other vacuum pumps, such as turbomolecular pumps, rotary vane pumps, or screw pumps with a high rotational speed may also benefit from embodiments of the present invention. A second aspect of the present invention provides a rotary machine including: at least one rotatable horizontal mounting shaft member supported on at least one bearing in a clearance hole, the rotatable horizontal mounting shaft member including a rotor element; The bearing includes an inner ring and an outer ring enclosing rolling elements; and the clearance hole includes an inner diameter larger than a diameter of the outer ring of the bearing; and the rotatable horizontal mounting shaft and the rotor element are housed. Within a certain hole, the stator hole and the clearance hole are offset relative to each other to compensate the shaft member supported in a radially downward position away from the center position of the clearance hole. Although the provision of a biasing member in the first aspect has the benefit of providing a resistance to a rotational imbalance and a predictability to a position of a shaft member, this can also be provided to some extent by gravity, where A shaft is mounted horizontally during operation, and this is especially true for larger machines with heavier shafts. In order to benefit predictably from this position, the stator and the clearance hole may be designed to have a relative offset corresponding to one of the offsets of the shaft within the clearance hole. Therefore, where the clearance hole diameter is said to be designed to be 100 micrometers larger than the outer diameter of one of the bearing housings, the clearance hole may be designed to have an offset of 50 micrometers from a center of a stator hole. A third aspect of the present invention provides a method for manufacturing a rotary machine including a rotatable shaft member which is horizontally mounted in use in a gap hole supported on at least one bearing. The shaft member includes At least one rotor element, the at least one rotor element being received in a certain hole, the method comprising: installing the rotatable shaft member supported on at least one bearing and including the at least one rotor in the clearance hole, The bearing includes an inner ring and an outer ring enclosing the rolling element, and the clearance hole includes an inner diameter larger than a diameter of the outer ring of the bearing; a stator is provided, and the stator has a hole to surround the at least one The rotor element, the stator hole and the clearance hole are offset relative to each other by an amount corresponding to an offset of a central position of the shaft member away from the clearance hole, due to the shaft member residing under one of the clearance holes On the surface. In some embodiments, the method further includes: a bearing biasing member for biasing the bearing in a radial direction away from the center position toward the downward direction of the hole to constrain the diameter of the shaft member To move. Further specific and preferred aspects are described in the accompanying independent and subsidiary claims. If appropriate, the characteristics of the subsidiary claims can be combined with the characteristics of the independent claims, and in addition to their combinations explicitly stated in the technical solution. Where a device feature is described as operable to provide a function, it should be understood that this includes providing a device feature or being adapted or configured to provide one of the device features.

Before discussing the embodiments in more detail, an overview is first provided. In a rotating machine having a shaft member supported on a rolling element bearing, a bearing or several bearings are usually required to slide axially at at least one end of the shaft member to accommodate growth of the shaft length due to heat or other influences. Axial sliding of the bearing is usually made possible by accommodating the bearing in a clearance hole. However, this clearance allows substantial changes in the radial position of the bearing, which is often detrimental to the performance of a machine. The change in bearing position results in a corresponding change in one of the radial clearances, which can cause component tightening, or in the case of pumps and engines, can result in loss of compression and mechanical efficiency. Specifically, in vacuum pumps, the ultimate pressure can be reduced, resulting in the need for a more expensive design to achieve satisfactory performance. Embodiments attempt to improve the radial control of rotating parts in a machine by biasing the bearings in a fixed direction. By holding the bearing in a known contact position or area, the variation in radial clearance in a machine can be significantly reduced. Depending on the nominal clearance and component tolerances, the amount of improvement can be as much as ten times. If (by offsetting the bearing) the variation in the position of the shaft is more determined, then the radial clearance in a machine can be reduced and a significant improvement in performance can be achieved. Alternatively, better control of the bearing position may allow some tolerances to be relaxed while still meeting certain performance requirements, thus reducing manufacturing costs. Examples in which embodiments may provide improved performance include turbines, gas and fluid compressors, vacuum pumps, and other precision rotating machinery. Specifically, in a vacuum pump, the embodiments can potentially be applied to a rotary vane pump, a turbo molecular pump, a screw pump, a multi-stage dry pump, and a mechanical booster. FIG. 1 schematically shows a cross section through a bearing 10 mounted in a clearance hole 12 according to the prior art. As can be seen, its position within the hole can vary significantly. FIG. 2 schematically shows the same cross section through a bearing installed in a clearance hole, but in this case, an offset load is applied to the bearing according to an embodiment. By applying a lateral load to the bearing, it has been demonstrated that during operation, changes in the position and rotational imbalance of the bearing 10 are significantly reduced. The biasing member that provides the lateral load is configured to provide a magnitude of the lateral load such that it allows the bearing to thermally expand in the bore, while overcoming or at least suppressing typical bearing response forces during rotation. A bearing can be strongly biased by any actual and cost-effective component to a designated position in one of its holes. These components include: mechanical and gas springs, electromagnetic power, permanent magnets, and gravity. For a two-axis machine such as one shown in FIG. 3, the bearing 10 may be forced to separate from a single spring 20. This can be a conventional coil or leaf spring or any other energized device. One potential embodiment may be the use of an annular spring, as shown in FIG. 3. As a bearing is biased away from the center, it is possible and practically desirable to reposition the hole to ensure that the bearing and the shafts it carries return to the desired center position. Alternatively, other components within the rotating machine may be offset to compensate for predicted offsets of the offset bearings and shafts. Figure 4 shows a longitudinal section through a rotating machine, and Figure 5 shows a cross section through a double-shaft machine of the same type. The rotary machine has a motor 30 for driving one of the shaft members 32. The shaft member 32 has a rotor element 34 which is mounted in a stator 36 having a certain hole 37. The rotating machine is a mechanical booster pump and has two rotating shaft members 32. The operation of the pump is affected by the gap. Increasing the gap reduces pump efficiency, and smaller gaps provide an increased risk of tightening the pump. The gaps that affect the operation of this pump include the rotor gap A between the rotor element 34 and the stator hole 37, the rotor-to-rotor gap B between the different rotor elements 34 shown in FIG. 5, and the bearing 10 to the gap hole 12, etc. It is easier to see in Figures 1 to 3. There is also a gap between the rotor element and the through hole (not shown). All of these will affect the operation of rotating machinery. However, in the statistical analysis of the performance of rotating machinery, it has been found that because the gap between the bearing and the clearance hole has an effect on many other gaps, a surprising amount is contributed to the overall performance of the rotating machinery. In this regard, it is found from statistical analysis that the shaft clearance tolerance will usually contribute more than 50% to the overall tolerance of the rotating machine. Therefore, it is judged that in the case where these variations can be reduced, then, an improved machine can be provided. Therefore, the improved machinery can be compensated by offsetting the bearing toward one edge of the clearance hole and offsetting the clearance hole, which is one of the positions of the shaft member that is not in the center of the clearance hole. The biasing member can be some form of spring or magnet, as shown in Figures 6 to 10, or with a horizontal mounting shaft, which can be simply attributed to gravity, the clearance hole relative to the stator hole and the through hole. Offset to provide improved performance. In the roots pump of FIG. 4, the shaft member 32 is mounted on the four bearings 10 and 16 in the respective clearance holes 12 and 18. At one end of the shaft member 32, the abutment plate 40 holds the shaft member 32 toward the motor, so that there is very limited axial movement at this end of the pump. Therefore, the bearing 10 at this end of the pump can be supported without allowing axial movement, and thus, it can be installed as an interference fit in the clearance hole 12 or it can be held in place using a strong biasing member in. The bearings 16 facing the opposite ends of the shaft member 32 are installed in the respective clearance holes 18 in a manner allowing axial movement, and are further biased toward the plate 40 by the axial biasing member 50. Therefore, bearing biasing members (not shown) that bias the bearings 10, 16 toward a fixed position within the respective clearance holes 12, 18 are selected so as to suppress radial movement due to rotational imbalance while allowing the shaft To move. In addition to the required axial movement that allows for thermal changes, it is also required during pump assembly in which the shaft member 32 slides into place with the plate 40 having a gasket 21 for changing their axial position. They are appropriately set to provide a suitable axial clearance. Figures 6 to 9 show examples of different types of biasing members of the bearings 10, 16 that can be used to bias the bearings in an embodiment of the invention. For the bearing 10 and the gap 12, the examples shown in FIGS. 6 to 9 are also applied to the bearing 16 and the gap 18. FIG. 6 shows a leaf spring 20 used as a biasing member of the bearing 10. The leaf spring 20 is mounted in one of the alignment recesses 14 in the clearance hole 12, thereby providing a known and predictable position for both the biasing member and the biasing shaft. FIG. 7 shows a dual shaft member system in which a magnetic biasing member 20 is installed between two shaft members and interacts with a magnet mounted on the housing of the bearing 10 so that the bearings in each clearance hole 12 are in the same direction. Up bias. Therefore, the magnets mounted on the bearings on the left-hand side of the drawing are repelled by the magnets 20, and their magnets mounted on the bearings on the right-hand side shown are attracted to the center magnet 20. There is an advantage to biasing the bearings in the same direction, as it reduces variations in the distance between the shafts. FIG. 8 shows a biaxial system similar to the system shown in FIG. 7, but in this case, the magnetic biasing member 20 installed between the two shafts and the magnet mounted on the housing of the bearing 10 Interact so that the bearings in each clearance hole 12 are offset in different directions, in this case offset away from the center position towards the outer edges of their respective clearance holes. If a magnet having a different polarity is used as the biasing member 20, the bearing can be attracted toward a center position. In either case, the biasing member does not extend into the clearance hole and biases the bearing away from a center position. FIG. 9 schematically shows how the use of a plurality of biasing members 20 and how to improve the stability of the bearing, and therefore how to improve the stability of the shaft, and to further reduce the rotational imbalance and associated vibrations and noise . As can be seen, a plurality of biasing members each having an element with a biasing force in a common direction are used. In this example, the common direction is downward, and therefore they work in conjunction with gravity. In some cases, the biasing member may be an integral part of the bearing. FIG. 10 shows an embodiment in which the bearing 10 has a housing made of a flexible material having a deformed circular shape. The inner shell 6 of the holding shaft is circular. One side of the housing has a diameter 8 larger than one of the other sides. The overall diameter is adapted to be slightly smaller than the clearance hole, where it is installed so that it is held in place by the deformed flexible shell. The center hole of the inner shell 6 will be biased toward one side of the shaft due to the deformed shape of the outer shell. FIG. 11 shows an embodiment in which an intermediate bridge part 12 is used to provide two points where a bearing is contacted from a single biasing member. This provides additional stability and a more predictable position of the shaft member with a single biasing member. The arrows in the diagram indicate the application of the bias load. Fig. 12 shows a further biasing member 24, 26, which can be used on the axially fixed end of the shaft member because it provides a fixed member that holds the bearing in a desired position. A curved plate 24 is provided between the screw 26 and the bearing 10 to reduce wear and tear on the bearing. In the "Invention", although it seems counter-intuitive to move the shaft away from a center position, because it seems to increase any lack of concentricity in the machine and thereby reduce performance, it is found that this offset provides the shaft One of the pieces has a more predictable position and reduces rotational imbalance. In addition, if the rotating machine is designed to compensate for this offset by offsetting the gap stator holes relative to each other, the shaft is actually moved back to a center position while still being held in a predictable and relatively stable position. In this way, embodiments provide: • The potential to relax manufacturing tolerances, thereby reducing machining costs. • Improved product performance by reducing the potential for nominal radial clearance. • Improved product reliability through better dimensional control, resulting in reduced tightening during testing, resulting in smaller assembly rework and debris. • Reduced tightening during testing, resulting in smaller assembly rework and debris. • Reduced performance variation due to narrow distribution of rolling gaps. • Repeatable shaft position improves the clarity of radial clearance assessment (paint spot testing, etc.), enabling fast radial clearance optimization. • Reduced noise and vibration In addition, implementing this concept into rotating machinery requires only small component changes, such as introducing an offset member to offset the bearing. Although the illustrated embodiments of the present invention have been disclosed in detail with reference to the accompanying drawings herein, it should be understood that the present invention is not limited to the precise embodiments and may be defined without departing from the scope of equivalent patents and the like In the context of the scope of the present invention, various changes and modifications can be implemented therein by those skilled in the art.

6‧‧‧ inner shell
8‧‧‧ shell
10, 16‧‧‧ Bearing
12, 18‧‧‧ clearance hole
14‧‧‧ align with the recess
20‧‧‧spring / biasing member
21‧‧‧Gasket
22‧‧‧Bridge Parts
24‧‧‧ curved plate
26‧‧‧Screw
30‧‧‧Motor
32‧‧‧ Shaft
34‧‧‧rotor element
36‧‧‧ Stator
37‧‧‧Stator hole
40‧‧‧board
50‧‧‧ axial offset member
B‧‧‧ Clearance

An embodiment of the present invention will now be further described with reference to the accompanying drawings, in which: FIG. 1 schematically shows a cross-section of a bearing through a clearance hole according to the prior art; FIG. 2 shows schematically A cross-section of a bearing through an installation in a clearance hole according to an embodiment; FIG. 3 schematically shows a cross-section of a bearing through a clearance hole installed in a biaxial machine according to an embodiment; FIG. 4 Shows a longitudinal section through a rotating machine; Figure 5 shows a cross section through the same machine; and Figures 6 to 12 provide examples of different biasing members for biasing bearings in a clearance hole according to an embodiment .

10‧‧‧bearing

20‧‧‧Spring

Claims (3)

A rotary machine includes: at least one rotatable horizontal mounting shaft member supported on at least one bearing in a gap hole, the rotatable horizontal mounting shaft member includes a rotor element; the bearing includes one of the enclosed rolling elements An inner ring and an outer ring; the clearance hole includes an inner diameter larger than a diameter of the outer ring of the bearing; and the rotatable horizontal mounting shaft and the rotor element are housed in a certain sub-hole, the stator hole and The clearance holes are offset relative to each other to compensate the shaft member which is supported in a radially offset position away from the center position of the clearance holes. A method of manufacturing a rotary machine including a rotatable shaft member which is horizontally mounted in a clearance hole supported on at least one bearing when in use, the shaft member includes at least one rotor element, the at least one The rotor element is accommodated in a certain hole, and the method includes: installing the rotatable shaft member supported on at least one bearing in the clearance hole, the bearing including an inner ring and an outer ring surrounding the rolling element And the gap hole includes an inner diameter larger than a diameter of the outer ring of the bearing; a stator having a certain sub-hole is provided to surround the at least one rotor element, the stator hole and the gap hole are offset relative to each other This corresponds to an amount that the shaft member is offset away from a center position of the clearance hole, which is due to the shaft member residing on a lower surface of the clearance hole. The method of claim 2, further comprising a bearing biasing member for biasing the bearing in a radial direction away from the center position toward the downward direction of the hole so as to restrain radial movement of the shaft member .