WO2006018916A1

WO2006018916A1 - Dynamic pressure fluid bearing

Info

Publication number: WO2006018916A1
Application number: PCT/JP2005/003314
Authority: WO
Inventors: Hisao Wada; Hideo Kaido; Tooru Nishida
Original assignee: Kawasaki Jukogyo Kabushiki Kaisha
Priority date: 2004-08-17
Filing date: 2005-02-28
Publication date: 2006-02-23
Also published as: CN100510443C; JP3636328B1; CN1898476A; KR20060037254A; JP2006057652A; KR100807889B1

Abstract

A foil type dynamic pressure gas bearing capable of providing excellent bearing performance by using a spring foil easily manufacturable and having excellent productivity and a dynamic pressure gas bearing capable of eliminating a restriction in a rotating direction by using an easily installable top foil fixing structure. The spring foil (12) formed of an elastic thin flat plate having a plurality of slits (16) is fitted to the inside wall of a bearing housing (11), a top foil (13) is disposed on the inside of the spring foil, and a rotating shaft (14) is disposed on the inside of the top foil. The spring foil (12) is bent at the positions of the slits (16) to form a large number of elastic beams in contact with the inside of the inside wall, and the rotating shaft (14) is elastically supported by the elastic beams.

Description

Specification

Hydrodynamic bearing

Technical field

[0001] The present invention relates to a hydrodynamic bearing for a high-speed rotating shaft, and more particularly to a hydrodynamic foil bearing.

Background art

[0002] There are two types of hydrodynamic bearings: static pressure type and dynamic pressure type. The dynamic pressure type bearing that generates pressure by rotating the shaft using ambient air is less expensive than the static pressure type that is externally pressurized by a compressor or the like. It is advantageous in terms of weight reduction, maintenance, etc., and is oil-free

V, there is also an advantage, especially oil-type hydrodynamic bearings are used in aircraft air conditioners, and are often used in small machinery used at high speeds such as air cycle machines. A foil type hydrodynamic bearing is composed of a top oil that forms a gas film with a shaft, a spring oil that elastically supports the oil, and a housing that holds them. There are various types of spring bearings for oil bearings such as bump type and leaf type.

FIG. 30 is a side sectional view showing an example of a bump oil air bearing. A bump oil air bearing that uses a bump type spring oil, as disclosed in Patent Document 1, etc., is a bump oil in which a thin metal plate is formed in a corrugated plate shape between a housing in which a rotating shaft is inserted and the rotating shaft. And a flat metal thin plate with a top lubricant coated with a solid lubricant inside, and the rotating shaft is hydrodynamically supported by a thin fluid film formed between the rotating shaft and the top oil, The top oil is supported by the inertia through the bump oil!

[0004] Bump fill air bearings are equipped with a self-adjusting mechanism for the rotating shaft by means of the bump fill panel function, so the requirements for the work accuracy of the bearing are not strict, but the bump foil needs to be molded into a complex shape, so press High precision molding process is required, and the process is complicated and difficult to manufacture and assemble.

Bump oil has high rigidity and small dimensional margin. In addition, if the rigidity is lowered, plastic deformation will occur due to use and the performance will be exhibited. FIG. 31 is a side sectional view showing an example of a leaf oil air bearing. Leaf-foil bearings that use leaf-type spring-foil oil are placed one on top of the other so that multiple leaf-foils can slide together on the inner periphery of the bearing housing, and there is a gap to draw air inside. The rotating shaft is supported at a distance, and the leaf oil is deformed to fit the rotating shaft in accordance with the axial load action of the rotating shaft to form an appropriate air layer. Yes.

The leaf oil also needs to be molded into a certain shape, which requires time and effort for molding, and also requires time and effort for the bearing.

[0006] Further, Patent Document 2 discloses an air bearing in which an assembly process is omitted by forming a spring oil from a single plate cover. The disclosed spring bearing oil has a rectangular elastic plate cut into one side at an appropriate interval along the long axis to form a multiple support plate, one end of which is provided in the notch inside the housing. It is fixed along the inside of the housing and fixed to the fixed mechanism, and the support plate is in contact with the top oil surrounding the rotating shaft and is supported by the spring action.

The spring oil used in the disclosed hydrodynamic foil bearing also needs to be molded to maintain the posture of the raised support plate.

[0007] Further, in Patent Document 3, a spring foil is accommodated in a three-layer structure in a bearing housing so that the innermost layer has a substantially quadrangular shape, the intermediate layer has a heptagonal shape, and the outermost layer has a substantially hexagonal shape. An oil journal bearing is disclosed. The triple-winding spring oil is formed with a groove across the width of the flat spring oil, and the portion of the groove bent between the grooves is used as an elastic beam.

In the bearing disclosed in Patent Document 3, the elasticity of the beam portion and the frictional damping due to the contact of the bent portion are obtained, and the self-excited vibration generated by the high-speed rotation of the journal can be suppressed. However, it is difficult to leave a certain thickness on a thin plate of spring oil with a thickness of several hundred μm or less, and it is difficult to form a groove. Even when it occurs, it develops in the width direction and is a problem in strength.

[0008] Conventionally, as described in Patent Document 1 and Patent Document 2, the top oil is screwed at one end to the inner cylindrical surface of the housing together with the bump oil or the spring oil. The other end is a free end that can be moved in the circumferential direction. In such a structure, the rotating shaft rotates in the direction from the free end direction to the fixed end direction so that air is wound between the rotating shaft and the bump fluid to form an air layer. When rotating from the top oil fixed end, the top oil wraps around the rotating shaft! Because the air layer cannot be formed, the rotation direction is limited to one direction.

As described above, the conventional top oil fixing method requires a special work for fixing to the inner surface of the housing, and has the problem of limiting the rotation direction of the rotating shaft to one side.

Patent Document 1: Japanese Patent Laid-Open No. 2002-0661645

Patent Document 2: JP 2002-364643 A

Patent Document 3: Japanese Utility Model Publication No. 6-76716

Disclosure of the invention

Problems to be solved by the invention

[0009] The problem to be solved by the present invention is to provide a foil type hydrodynamic bearing having excellent bearing performance using a spring foil that is easier to manufacture and excellent in mass productivity. In addition, a second problem to be solved by the present invention is to provide a peristaltic fluid bearing having no restriction in the rotational direction by using a top oil fixing structure that is easy to mount.

Means for solving the problem

[0010] In order to solve the above problems, the hydrodynamic bearing of the present invention is mounted with a spring oil formed of a thin flat plate having a plurality of slits on the inner wall of the bearing housing, and the top is placed inside the spring fill. This is a foil type bearing in which the oil is arranged and the rotating shaft is arranged inside the top oil, and the spring oil is bent at a position with small rigidity and has many elastic beams that are in contact with the inner side of the inner wall. A rectangular cross section is formed, and the rotating shaft is elastically supported by this elastic beam.

A slit is provided in the spring oil formed of a thin flat plate to give a strength difference in bending rigidity depending on the location. When this spring oil is attached to the inner wall of the bearing housing, it is bent at a slit position with a small rigidity. A large number of elastic beams are formed between adjacent slits in contact with the inner wall, forming a polygonal cross section. This elastic beam can support the top foil in inertia. [0011] The rotating shaft is wrapped in top oil, and a gas such as air is inserted between the rotating shaft and the top oil as it rotates to form a gas layer, and the rotating shaft is supported hydrodynamically. In particular, high-speed rotation can be performed smoothly. As the rotation speed of the rotating shaft increases, the thickness of the gas layer increases and the top oil is pressed against the inner wall of the bearing housing to increase the elastic force of the spring oil. It starts to rotate.

The slit can be provided in a direction substantially parallel to the rotation axis when the spring oil is inserted into the bearing housing, and the flange can be bent to form a node at the slit position. The difference in bending stiffness between elastic beams is caused by the difference in the length of the oil part sandwiched between the slits.

[0012] The length of the elastic beam can be changed by setting the slits at unequal pitches. Although the bending rigidity is weak at the long elastic beam, the inner diameter of the bearing is reduced because the distance between the inner wall of the housing and the top foil is increased. The bending rigidity increases at the short beam section, and the inner diameter of the bearing increases because the top oil approaches the inner wall of the housing. Therefore, when the load is small or the vibration is small, the spring with the small inner diameter supports the shaft, and when the load is large or the vibration is large, the shaft is supported even at the large inner diameter. It will have a support structure with a unique panel characteristic.

[0013] Slits having different lengths may be alternately arranged. The part with the long slit is broken, and the part with the short slit is hard to break. Therefore, the long slit is initially refracted and contacts the wall of the housing, and the short slit does not break. Therefore, the rotation of the rotating shaft with the small inner diameter of the cylinder made by the top oil is small. When the rotating shaft begins to rotate, the spring oil is refracted even at the short slit position, and the top oil force S approaches the inner wall of the housing, the inner diameter increases, the length of the elastic beam decreases, and the rigidity of the spring oil increases. . In this way, it is possible to obtain a bearing that exhibits characteristics such that when the load is small, the rigidity of the spring foil is low and the rigidity becomes high when the load at which the top oil is easily opened increases.

[0014] The length of the beam formed between the slits of the spring oil is made equal, and the width of the slit is reduced. It may be changed. Since the slit portion does not generate support rigidity for elastically supporting the rotating shaft, the rigidity distribution can be designed relatively easily in order to provide an appropriate difference in support rigidity for each location in the circumferential direction of the housing. By providing a difference in the circumferential direction of the rigidity of the foil bearing, elliptical motion can be generated on the rotating shaft, and vibration can be suppressed. The slits parallel to the rotation axis may be arranged at equal intervals so that the rigidity of the elastic beams is almost equal to each other!

The slit may be formed by force from the side end of the oil toward the center line. If the slit is opened at the side end, the rigidity is reduced at the side of the oil, and it is possible to prevent the rotation shaft from hitting one side.

[0015] The slit can have a shape in which the flat plate force is separated from the remaining sides excluding the bottom, such as two sides of the triangle and three sides of the rectangle. When this spring oil is installed along the top oil, the tongue that extends tangentially at the position of each slit reaches the inner wall of the bearing housing to become a panel, and supports the top oil.

The rigidity may be changed by making the slit into a thick cut shape so that the distance to the ridgeline of the adjacent slit varies depending on the distance of the edge of the flat plate. For example, if the cut-off shape is a shape in which a triangle or semicircular shape protrudes into the slit, the effective width of the beam is small and the rigidity is weak while the protruding portion becomes a fulcrum, but the rotation speed increases and the top oil is transferred to the housing. Stiffness increases as it approaches. In addition, when the slit shape is semicircular, the length of the elastic beam is initially large and the short beam acts as the top oil spreads. It exhibits the characteristics that the rigidity is strengthened.

Thus, desired rigidity characteristics can be obtained by selecting the slit shape.

[0016] Further, a part of the slits may be provided in parallel to the side end line of the flat plate of the spring oil.

By dividing the zone into several zones in the direction of the rotation axis, the same effect can be obtained if springs having different rigidity are arranged in the direction of the rotation axis.

Spring oil can be formed from one end of one thin plate, and solid lubricant can be applied to the other end which is left to the extent that it surrounds the rotating shaft. The top oil is also a force that is always placed inside the spring oil. The slit portion of the spring oil can be provided with multiple slits at high density. Although the slit portion is refracted and comes into contact with the inner wall of the housing, if a plurality of slits are provided at high density, a large number of ridge lines along the inner wall share the pressing force, so that the contact surface pressure can be reduced.

[0017] It is also possible to provide a slit parallel to the side edge of the flat plate of the spring oil at the center of the portion that becomes the beam between the slits. The center of the beam is in contact with the top oil and gives rigidity to the top foil. The slit in the center of the beam increases the contact area between the spring oil and the top foil, reducing the contact pressure. Has the effect of

The spring oil may be wound around the top oil in multiple layers. In particular, the inner spring-foil slit should be aligned with the center of the outer spring-foil beam.

[0018] When the multi-layer structure is used, the rigidity increases as the top oil spreads, so that the low-speed rotational force can be supported with an appropriate rigidity up to the high-speed rotation.

If a plurality of spring oils are arranged so as to overlap each other, it is possible to obtain an effect of attenuating the vibration of the bearing by using the friction of the oils.

[0019] It is preferable that the slit of the spring oil is rounded at the end so as to relieve the stress generated at the end.

The slit can be manufactured by etching. By using the etching method, it is possible to accurately and easily form slits with extremely fine dimensions as in the case of a printed circuit board.

[0020] The bearing housing may be formed such that the cross section of the inner hole is polygonal, and the spring foil slit is positioned at the apex of the polygon. When such apex exists, it becomes easier to fix the spring oil. In addition, if the apex angle of the inner hole section polygon of the bearing housing is positioned in the middle of the beam formed between the slits of the spring oil, the sectional area of the space formed by the housing wall and the spring oil is set. As the flow rate increases, a large amount of cooling fluid circulates and the range of high-speed rotation in which the bearing can be used is expanded.

[0021] In addition, a stop wall rising from the inner wall surface is formed at each of the two locations on the inner wall of the housing where both ends of the top oil come into contact, and the two top oils formed by the elastic flat plate cover are stopped. It is preferably inserted and fixed so as to stretch between the walls. In addition, stop The angle of the wall surface is preferably in the range of 60 ° force and 90 ° with respect to the inner wall surface. In addition, it is preferable to form a digging with a triangular cross section on the front surface of the stop wall so that the top oil naturally draws a curve and is locked.

[0022] When this locking mechanism is used, in order for the top oil to be detached from the housing, the force of the top oil moving in the width direction of the housing, the axial center position of the top oil cylinder shifts, and the edge becomes The force over the stop wall and the top oil circumference must be shortened until it is shorter than the circumference connecting the end of the stop wall. However, if the movement of the top oil in the width direction is suppressed, there will be almost no change that satisfies this condition.Therefore, as in the conventional method, one end of the top oil is fixed to the inner wall of the housing by screws or welding. In comparison, this locking mechanism is an excellent method that can be securely fixed while its structure and method of use are extremely simple.

It is also easy to remove the top oil and disassemble the device.

[0023] Although the movement of the top oil in the width direction can be easily suppressed by friction between the housing and the top oil even in a normal mounting state, a clasp is attached to the side surface of the stop wall to prevent it more reliably. It can be set or fixed on the side of the housing with an ear at the end of the top oil.

In this method, both ends of the top oil are fixed to the housing, and air can be introduced between the top oil and the rotating shaft from any fixed portion, so the rotating shaft can be rotated in either direction. Also, the performance as a fluid bearing can be exhibited.

In order to enhance the cooling capacity by promoting the introduction of air from the space in the fixed part, it is preferable to increase the triangular excavation formed on the front surface of the vertical stop wall. In addition, in the drilling, the inlet (leading) side of the bearing in the rotational direction can be deeper than the outlet (trading) side to facilitate air introduction.

[0024] By providing the top oil together with the spring oil in the circumferential direction, the flying performance and the load capacity can be adjusted. In particular, by providing the top oil at unequal pitches, bearing dynamic characteristics with high vibration stability can be obtained.

With this locking mechanism, it is also possible to fix spring oil or bump foil together with top oil. [0025] Further, in order to solve the above-mentioned problems, the present invention provides a spring oil having a thin flat plate force provided with a plurality of slits used in a foil type hydrodynamic bearing. In addition, a stop wall having an angle of approximately 60 ° force 90 ° with respect to the inner wall surface is formed at the position of the inner wall of the housing where both ends of the top oil come into contact, and a digging having a triangular cross section is formed on the front surface of the stop wall. A top foil mechanism that can be used for hydrodynamic bearings that use various foils that are fixed by extending and inserting the top oil between the surfaces of the stop wall. Provide a stop mechanism.

[0026] According to the hydrodynamic foil bearing of the present invention, it is possible to manufacture a spring-foil oil more easily and accurately than before and easily incorporate it into the bearing. However, the adjustment fee according to the demand is increased, and the stability at high speed is also improved. In the foil bearing of the present invention, the rotating shaft can rotate in any direction. Brief Description of Drawings

FIG. 1 is a cross-sectional view of a dynamic pressure gas bearing according to a first embodiment of the present invention.

FIG. 2 is a slit layout diagram of spring oil used in the dynamic pressure gas bearing of the first embodiment.

FIG. 3 is a drawing for explaining end processing of a slit of spring oil.

FIG. 4 is a plan view schematically showing the state of a slit of spring oil constituting the feature of the second embodiment of the present invention.

FIG. 5 is a cross-sectional view of a dynamic pressure gas bearing according to a second embodiment.

FIG. 6 is a plan view schematically showing the state of a slit of spring oil constituting the feature of the third embodiment of the present invention.

FIG. 7 is a plan view of a spring oil used in a dynamic pressure gas bearing according to a fourth embodiment of the present invention.

FIG. 8 is a drawing for explaining a state in which spring oil is incorporated in a dynamic pressure gas bearing of a fourth embodiment.

FIG. 9 is a plan view of a spring oil used in a dynamic pressure gas bearing according to a fifth embodiment of the present invention.

FIG. 10 is a drawing for explaining the state of incorporation of spring oil in the dynamic pressure gas bearing of the fifth embodiment. FIG. 11 is a plan view of a spring oil used in a dynamic pressure gas bearing according to a sixth embodiment of the present invention.

FIG. 12 is a drawing for explaining the state of incorporation of spring oil in the dynamic pressure gas bearing of the sixth embodiment.

FIG. 13 is a plan view of a spring oil used in a dynamic pressure gas bearing according to a seventh embodiment of the present invention.

FIG. 14 is a plan view of a spring oil used in a dynamic pressure gas bearing according to an eighth embodiment of the present invention.

15] A sectional view of a dynamic pressure gas bearing according to a ninth embodiment of the present invention.

FIG. 16 is a plan view of a spring oil used in the dynamic pressure gas bearing of the ninth embodiment. [17] FIG. 17 is a perspective view illustrating a spring oil locking mechanism.

[18] FIG. 18 is a perspective view illustrating a spring oil locking mechanism with a drop-off prevention mechanism added thereto.

[19] FIG. 19 is a perspective view for explaining another mechanism in which a spring oil locking mechanism is added with another drop-off prevention mechanism.

FIG. 20] A sectional view showing a state in which the locking mechanism of the ninth embodiment is applied to a bump foil bearing device.

21] A sectional view illustrating a case where a plurality of locking mechanisms are used in the dynamic pressure gas bearing of the ninth embodiment.

FIG. 22 is a cross-sectional view of a dynamic pressure gas bearing according to a tenth embodiment of the present invention.

FIG. 23 is a plan view of a spring oil used in the dynamic pressure gas bearing of the tenth embodiment.

FIG. 24 is a drawing showing another shape example of the tongue formed on the spring oil.

FIG. 25 is a drawing showing still another example of the shape of the tongue formed on the spring oil.

FIG. 26 is a plan view of a spring oil used in a dynamic pressure gas bearing according to an eleventh embodiment of the present invention.

27] A sectional view of a dynamic pressure gas bearing according to a twelfth embodiment of the present invention.

28] A sectional view of a dynamic pressure gas bearing according to a thirteenth embodiment of the present invention.

29] A sectional view of a dynamic pressure gas bearing according to a fourteenth embodiment of the present invention. FIG. 30 is a cross-sectional view showing an example of a conventional dynamic pressure gas bearing.

FIG. 31 is a cross-sectional view showing another example of a conventional dynamic pressure gas bearing.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the best mode of the hydrodynamic bearing of the present invention will be described in detail.

Example 1

FIG. 1 is a cross-sectional view of a dynamic pressure gas bearing according to one embodiment of the present invention, and FIG. 2 is a slit layout diagram of a spring oil used therefor.

In the dynamic pressure gas bearing 1 of this embodiment, the spring oil 12 is arranged so as to contact the inner wall of the cylindrical housing 11, and the top oil 13 is fixed to the inner wall of the nose housing with the top oil 13 fixed to the inner wall. The rotating shaft 14 is accommodated through an air layer 15 in a cylindrical shape that is formed so as to make one round along the inner wall.

The spring oil 12 is a thin elastic metal plate having a thickness of several hundreds of meters, and as shown in FIG. 2, slits 16 having the same shape are arranged in parallel to the winding direction of the oil. Slit 16 force S Since the metal part is small at a certain position and its rigidity is weak, when it is loaded into the dynamic pressure gas bearing 1, it is bent at the slit position as shown in Fig. 1, and the spring oil 12 is partially vacant. It becomes a cylinder with a polygonal cross section.

[0031] The spring oil 12 having a polygonal cross section is usually formed by bending at the position of the slit 16, contacting the inner wall of the wing, and the portion sandwiched by the slit 16 is an elastic beam. The top top oil 13 in the inside is supported by inertia.

When the gap between the slits of the spring oil 12 is long, the rigidity of the long elastic beam A formed between them becomes small, and the rigidity of the short elastic beam B existing at a short distance becomes large. Thus, the rigidity of the spring oil 12 can be adjusted by the position of the slit, so that the desired elasticity along the circumference of the bearing can be provided with the desired elasticity.

[0032] The top oil 13 is a thin 100 μm-thick elastic metal plate treated with a solid lubricant to reduce the coefficient of friction with the rotating shaft 14, and one end is fixed to the inner wall of the housing 11. The other end is a free end.

The rotary shaft 14 is rotated in the direction of the free end of the top oil 13 as shown by the arrow in FIG. When rotation starts, air is drawn between the rotating shaft 14 and the top oil 13 An air layer 15 is formed. The air layer 15 significantly reduces the rotational friction of the rotating shaft 14 and enables smooth rotation.

However, in the dynamic pressure gas bearing of this embodiment, when the rotary shaft 14 rotates in the opposite direction from the fixed end, the top oil 13 cannot wind up around the surface of the rotary shaft 14 so that air can be taken in. It will fail to form.

[0033] When the rotation of the rotary shaft 14 becomes high speed, the air layer 15 develops, and when the top oil 13 is pressed against the inner wall of the wing 11, the beam A is deformed and the elastic value gradually increases. However, when the top oil 13 is short and comes into contact with the elastic beam B, the strong and rigid beam B acts, and the rotating shaft 14 is supported with even stronger stiffness.

Therefore, with the configuration of this embodiment, the bearing is supported with relatively weak rigidity at the start of rotation, and is supported with strong rigidity that resists strong stress at high speed rotation, and the bearing has stepwise rigidity suitable for the rotation speed. A device can be obtained.

In addition, by selecting the thickness and material of the elastic metal flat plate and appropriately selecting the number and interval of the slits, the support rigidity and the rigidity distribution in the circumferential direction of the housing can be easily adjusted.

[0034] As schematically shown in FIG. 3, it is preferable that the end of the slit 16 is rounded to reduce the stress.

The hydrodynamic gas bearing of this embodiment is manufactured and manufactured without the need for molding calorie using a press machine or the like by simply opening a slit in the spring oil as compared to a conventional oil-type gas bearing or leaf-type gas bearing. Easy to assemble. In addition, the spring oil can be processed by using an etching technique used for manufacturing printed circuit boards, etc. If the etching technique is used, the accuracy is high and mass production is easy.

Example 2

FIG. 4 and FIG. 5 are drawings for explaining another embodiment of the present invention, and FIG. 4 is a plan view schematically showing the state of the slit of the spring oil constituting the feature of this embodiment. is there. Fig. 5 is a cross-sectional view of the dynamic pressure gas bearing of the present embodiment, where (a) is the state at the beginning of rotation, (b) is the state in the middle of high speed, and (c) is the state during high speed rotation. Indicates.

[0036] In the spring oil 21 used in the present embodiment, slits having different lengths are alternately arranged. It has been. The part where the slit 22 is long has a small remaining flat plate width, so the rigidity is weak and the foil is easily broken. On the other hand, the part with the short slit 23 is harder to break.

Therefore, at the time of stopping, as shown in Fig. 5 (a), the long slit 22 part is refracted and comes into contact with the housing wall 24, and the short slit 23 part is hard to break. The inner diameter of the cylinder is small. Shake of the rotary shaft 26 supported by the top oil 25 is small! /,

[0037] When the rotating shaft 26 starts to rotate and a large load is applied, an air layer 27 is generated between the rotating shaft 26 and the top oil 25 as shown in FIG. The spring oil 21 is refracted even at the position of the slit 23 near the inner wall 24, and the length of the elastic beam is shortened and the rigidity of the spring oil 21 is increased.

Furthermore, when the rotating shaft rotates normally, as shown in Fig. 5 (c), the air layer 27 is generated and the top oil 25 opens sufficiently concentrically with the inner wall 24 of the housing, so that it has high rigidity. It is supported by a short elastic beam.

[0038] In this way, a dynamic pressure gas bearing incorporating spring oil in which slits of different lengths are alternately arranged has a small load! / Sometimes the rigidity of the spring oil is low and the top oil opens. It is possible to obtain a bearing that exhibits favorable characteristics that rigidity increases with an easy load.

Example 3

[0039] Fig. 6 is a plan view of a spring oil with a slit cut from the side end and a central portion remaining.

As shown in FIG. 6, the dynamic pressure gas bearing of the present embodiment incorporates a spring foil 31 in which a plurality of slits 32 are formed so as to leave a central band with a constant width at the center of the foil by cutting the end force on the oil side. Is. Since the spring oil is separated at the side of the bearing in this way, the elastic beams move relative to each other, so that the rigidity at the side is weak compared to the internal rigidity, and when the rotating shaft tilts, It is possible to avoid contact with one piece. Example 4

FIG. 7 is a plan view of the spring oil used in the dynamic pressure gas bearing of the fourth embodiment, and FIG. 8 is a drawing for explaining the state of incorporation of the spring oil of FIG.

As shown in Fig. 7, the spring oil used in this example is a single elastic material. This is a flat plate 33 in which a spring oil 34 part and a top oil 35 part are formed together. The spring oil 34 part has slits in place, and the top oil 35 part has a solid lubricant on the surface. In the figure, when the spring oil 34 is formed with 4 slits and incorporated into the bearing, the spring oil partial force square is formed. However, more slits may be formed, That's not good.

[0041] The dynamic pressure gas bearing 3 of the present embodiment shown in FIG. 8 is obtained by rounding a portion 35 of the elastic flat plate 33 to which a solid lubricant is applied to form a top oil and further forming a portion 34 having slits at each slit position. It is refracted into a polygonal spring oil and inserted into the inner wall 36 of the nosing.

As indicated by the dotted line in the figure, the foil 37 may be prevented from shifting by the rotation of the rotating shaft by extending and fixing the end 37 of the spring oil to the inner wall 36 of the nosing.

Since the dynamic pressure gas bearing of this embodiment integrates the spring oil and the top oil, the number of parts constituting the bearing can be reduced, and the production can be rationalized.

Example 5

FIG. 9 is a plan view of the spring oil used in the dynamic pressure gas bearing of the fifth embodiment, and FIG. 10 is a view for explaining the state of incorporation of the spring oil of FIG.

As shown in FIG. 9, the spring oil 41 used in this embodiment is provided with a plurality of slits 43 adjacent to and parallel to a slit portion 42 formed with an elastic beam in between. When the spring oil 41 is loaded into the housing inner wall 44, as shown in FIG. This reduces the pressure and reduces the wear on the inner wall 44 of the housing.

If the housing inner wall 44 in contact with the spring oil 41 is extremely worn, there is a risk that the elastic value of the elastic beam 45 may decrease and the desired performance may not be achieved. This has the effect of reducing the labor of adjustment.

Example 6 FIG. 11 is a plan view of the spring oil used in the dynamic pressure gas bearing of the sixth embodiment, and FIG. 12 is a drawing for explaining the state of incorporation of the spring oil of FIG.

As shown in FIG. 11, the spring oil 47 used in this embodiment is placed in a portion that becomes an elastic beam by being sandwiched between vertical slits 48 formed in the width direction of the spring foil 47. A plurality of lateral slits 49 are formed in parallel to the side edges.

When the spring oil 47 is charged into the inner wall 46 of the housing, it is refracted while contacting the inner wall 46 at the position of the vertical slit 48 to form a tubular spring oil having a polygonal cross section. As shown in FIG. 12, the spring oil 47 is brought into surface contact with the surface of the top oil 50 at the positions of the plurality of lateral slits 49 to reduce the contact pressure.

Example 7

FIG. 13 is a drawing of a spring oil used in the dynamic pressure gas bearing of the seventh embodiment.

The spring oil 51 used in this embodiment forms slits 52, 53, 54 of the same length at appropriate intervals, and the length of the elastic beam formed between adjacent slits is selected. In addition to adjusting the rigidity of the beam, the width of the slit is selected to adjust the distribution of the elastic beam.

Since the elastic beam is formed between the slit end lines, there is no panel that elastically supports the rotating shaft in the wide slits 53 and 54, so the spring can be selected by selecting the slit width appropriately. The elastic distribution of the oil 51 can be adjusted. By providing a difference in rigidity in the circumferential direction of the bearing, vibration stability performance that suppresses vibrations associated with high-speed rotation is improved.

Example 8

FIG. 14 is a plan view of the spring oil used in the dynamic pressure gas bearing of the eighth embodiment. The spring oil 56 used in this embodiment is formed in the width direction of the spring oil 56. When a plurality of horizontal slits 58 are formed parallel to the side edges of the spring oil 56 at the portion sandwiched between the vertical slits 57 to be divided into appropriate widths and assembled into the housing The support rigidity is changed in the axial direction of the rotary shaft. For example, side If a lateral slit 58 parallel to the end is formed near the side end to increase the rigidity at the center of the bearing and decrease the rigidity at the ends of both sides, it is possible to prevent the rotation shaft from hitting one side.

Example 9

FIG. 15 is a cross-sectional view schematically showing the dynamic pressure gas bearing of the ninth embodiment, FIG. 16 is a plan view of the spring oil used in this embodiment, and FIG. 17 shows the locking mechanism of the spring oil. It is a perspective view to explain.

The dynamic pressure gas bearing 6 of the present embodiment is a gas bearing incorporating spring oil 62 in which slits of the same shape are arranged at equal intervals.

The spring oil 62 and the top oil 63, each having a length approximately equal to the inner circumference of the housing, are fitted inside the bearing housing 61, and the rotating shaft 64 is inserted into a cylinder formed by the top oil 63.

[0047] When the spring oil 62 is rolled into a cylindrical shape having a diameter smaller than that of the housing 61, and is loosened after being placed in the cylinder of the housing, the spring oil 62 spreads by the panel force of the oil and adheres closely to the inner wall. At this time, the position of the slit 67 formed in the spring oil 62 becomes a polygonal cylindrical shape in contact with the inner wall as a ridgeline, and an elastic beam is formed between adjacent ridgelines.

When the top oil 63 is also rolled into a cylindrical shape having a diameter smaller than that of the housing 61 and inserted into the spring oil 62 to be loosened, the spring oil 62 is pressed and spread from the inside by its own panel force. The length of the top oil 63 is such that it almost reaches the end face of the locking mechanism 66 after making one round inside the housing 61. Both ends of the top oil 63 are fixed to the inner wall of the housing 61 by a locking mechanism 66 as shown in FIG.

[0048] The spring oil 62 is formed of a thin, elastic metal flat plate having a thickness of several hundred μm.

As shown in FIG. 16, the spring oil 62 is formed in a rectangular shape and has a longitudinal direction and a lateral direction. The short direction of the spring oil 62 is a direction that is substantially parallel to the axis of the rotary shaft when mounted in the housing 61. A plurality of slits 67 having the same shape are arranged at equal intervals in the longitudinal direction of the spring oil 62, and the slit 67 has a length in the longitudinal direction (slit length) of the slit in the short direction of the spring oil 62, The spring foil 62 has a slit width (slit width) in the longitudinal direction.

When the spring oil 62 is bent, the slit 67 receives the bending deformation. It is distributed between the bending deformation and the bending deformation received by the elastic beam formed between the slit 67 and the adjacent slit 67.

The longer the slit length of the slit 67 with respect to the length of the spring oil 62 in the short direction, the more the spring oil 62 bends in a V-shape at the slit 67, and the elastic beam becomes a straight line in cross section, and the elastic beam is flat. It will be shaped, and most of the bending deformation of the spring oil 62 will be handled by the slit 67. In addition, the smaller the slit length of the slit 67 with respect to the length of the spring oil 62 in the short direction, the more the elastic beam has a planar shape. The bending deformation of Nguf oil 62 tends to be handled by both the slit 67 and the elastic beam.

On the other hand, the size of the gap between the inner wall of the top oil 63 and the outer wall of the cylindrical shaft 14 is an important factor governing the performance of the foil type hydrodynamic bearing. Therefore, it is important to manage the accuracy of the gap to a value higher than a predetermined value when manufacturing a foil type hydrodynamic fluid bearing. The spring oil 62 and top oil 63 are unavoidable for the plate material used! /, And there is a plate thickness error, etc., so manufacturing error is expected in the production of foil type hydrodynamic fluid bearings. In the above, it is required to manage the accuracy of the gap to a value greater than a predetermined value. This allows foil type hydrodynamic bearings to function as designed within an acceptable range.

[0050] In such a situation where it is necessary to strictly control the accuracy of the gap, the spring-type hydraulic fluid bearing 62 must be made of a slit 67 in order to function as designed within an allowable range. It is preferable that most of the bending deformation of the spring oil 62 is handled by the slit 67 so that the elastic beam is bent in a V shape in a straight line in a cross-sectional view and the elastic beam is planar. It has been found. According to the bending deformation analysis of the spring oil and the bearing performance experiment, when the bending deformation of the spring oil 62 is handled by the slit 67 and the elastic beam, the elastic beam of the bending deformation of the spring oil 62 is It was found that the bending deformation ratio (the bending ratio of the elastic beam) is preferably 15% or less. If the bending ratio of the elastic beam is greater than 15%, the variation of the bending deformation of the elastic beam due to the plate thickness error, etc. increases, and the inner wall of the top oil 63 inscribed in the elastic beam that has been bent and deformed by the spring oil 62 And the size of the gap between the outer wall of the cylindrical shaft 14 fluctuates. Oil type hydrodynamic bearings will not function as designed.

[0051] Therefore, the ratio of the slit length of the slit 67 to the length in the short direction of the spring oil 62

((Slit length of slit 67) / (Length in the short direction of spring oil 62)) (Relationship between slit length ratio and bending ratio of the elastic beam above) This was investigated by analysis. According to this analysis, when the slit length ratio is 0%, the bending ratio of the elastic beam is 29%. When the slit length ratio is 60%, the bending ratio of the elastic beam is 27%, and the slit length ratio is When it is 70%, the bending ratio of the elastic beam is 21%, when the slit length ratio is 80%, the bending ratio of the elastic beam is 18%, and when the slit length ratio is 80%, the bending ratio of the elastic beam is When the slit length ratio is 90%, the elastic beam bending ratio is 8%, and when the slit length ratio is 95%, the elastic beam bending ratio is 1% or less. It was. It was also found that when the slit length ratio exceeds 90%, the slit 67 is too long and the strength of the spring oil 62 cannot be secured. Also, according to the results of bearing performance experiments, it is desirable that the slit length ratio is 80% or more and 90% or less, and it is further desirable that the slit length ratio is 80% or more and 85% or less. Is done. When the slit length ratio is less than 80%, the elastic beam has an arc shape in cross-sectional view and the elastic beam has a cylindrical surface shape.Therefore, the gap between the inner wall of the top wall 63 and the outer wall of the cylindrical shaft 14 is reduced. The size of the gap will deviate from the expected tolerance. Also, when the slit length ratio is greater than 90%, the strength of the spring oil 62 cannot be secured, and when the slit length ratio is less than 85%, the strength of the spring oil 62 is securely secured. be able to.

In addition, the groove width (slit width) of the slit 67 is 1.0 or more times the thickness of the elastic metal plate forming the spring oil 62, or 1.0 times the thickness of the elastic metal plate. It is preferably not smaller. The upper limit of the groove width of the slit 67 is determined so that the bending ratio of the elastic beam is 15% or less in consideration of the size of the gap between the slits 67 and the like. If the groove width of the slit 67 is smaller than 1.0 times the thickness of the elastic metal plate, the spring oil 62 will not bend into a V shape at the slit 67 when the spring oil 62 is bent and deformed. Therefore, the elastic beam is less likely to be straight when viewed in cross section, and the bending ratio of the elastic beam is greater than 15%.

[0052] The locking mechanism 66 is formed by forming a pair of triangular grooves 69 on the inner wall of the housing 61 back to back. It is. A ridge 70 left uncut between a pair of triangular grooves 69 is formed, and both sides of the ridge 70 become almost vertical stop walls 68! /.

The end portion of the top oil 63 falls into the triangular groove 69 and is pressed against the inner wall of the housing 61 by the bunker that tries to loosen the oil itself. In order to prevent it from coming off more reliably, it is preferable that both edges of the top oil 63 hit against the stop wall 68 and stop. /.

The top surface of the ridge 70 is the same as the inner surface of the top oil 63 when viewed from the viewpoint of the function of the force that is the same height as the inner surface of the housing 61 due to the convenience of the manufacturing process formed by digging the inner wall of the housing 61. You may protrude to the same Cf standing. The higher the peak 70 is, the more difficult it is for the top oil 63 to come off.

[0053] When this locking mechanism 66 is used, the force of the top oil 63 moving in the width direction of the housing 61 is shifted. If the top oil 63 is not shrunk until the circumference of the top oil 63 becomes extremely shorter than the circumference connecting the stop wall 68 to the stop wall 68 on the opposite side, the top oil will be released from the housing force. There is no. Normally, the top oil 63 is pressed against the inner wall of the housing 61 by the panel force through the spring oil 62, so the friction force is strong and it is difficult to move in the width direction. In addition, when the top oil 63 is contracted and the diameter of the cylinder is reduced, the end edge bites into the stopper wall 68, and a force is applied in the direction of «>.

[0054] The bottom surface of the triangular groove 69 is formed as a surface in contact with the cross-sectional circle of the inner wall of the housing 61, and an end portion extending in a tangential direction from the cylindrical shape formed by the top oil 63 extends along the bottom surface. It is preferable that the edge hits the stop wall 68 and stops. By making the cylindrical force smoothly transition to the flat surface when the top foil 63 fits in the triangular groove 69, it can be prevented from bulging in the transition region. If there is a bulging portion, the top oil 63 comes into contact with the rotating shaft 64, which causes rotation failure, frictional heat generation, wear, etc., which is not preferable.

When the rotating shaft 64 rotates, air is sucked between the top oil 63 and the rotating shaft 64 through a gap formed in the locking mechanism 66, and an air layer 65 is formed. Top oil 63 is not free end because both ends are constrained by friction with the inner wall of housing 61. Since the air introduction opening is provided between the puff oil 63 and the rotating shaft 64, unlike the bearing of the first embodiment, the air layer 65 is generated even if the rotating shaft 64 rotates in either the left or right direction. Is possible.

As the rotating shaft 64 rotates, the air layer 65 develops and the top oil 63 is pressed against the inner wall of the housing 61. Therefore, the elastic beam of the spring oil 62 is deformed during high-speed rotation, and the rotating shaft 64 is supported by strong rigidity. Will come to be.

[0056] It is preferable that the triangular groove 69 is made to have an appropriate depth so that the supply of air is facilitated so that the air layer 65 is generated and generated smoothly.

When the rotation direction of the bearing is fixed, the triangular groove 69 on the rotation direction inlet (leading) side is deeper than the outlet (trading) side, and air is introduced between the top oil and the wording. It ’s good.

[0057] The locking mechanism 66 has a very simple structure as compared with the conventional method in which one end of the top oil is fixed to the inner wall of the housing by screws or welding, and has a special structure for locking to the top oil 63. The assembly force can also be saved without the need for machining. In addition, it is easy to disassemble the bearing device, and it is easy to modify it in accordance with maintenance and change of conditions.

The spring oil 62 can be sufficiently supported by being covered with the top oil 63 and pressed, but it is supported in the same way as the top oil 63 using the locking mechanism 66, and the top oil 63 is supported from above. Then, when assembling the bearing device, spring oil 6

It is convenient because the top oil 63 can be inserted after 2 is fixed.

FIGS. 18 and 19 are perspective views showing a state in which a mechanism for reliably preventing the top oil 63 from falling off is added. In both cases, the top oil 63 is prevented from moving off the inner wall of the bearing housing 61 in the axial direction.

In FIG. 18, the stopper 71 is screwed to the side end of the peak 70 of the locking mechanism to restrict the movement of the top oil 63 in the width direction. The upper edge of the stopper 71 is lowered from the upper surface of the peak 70 so that the movement of the rotating shaft is not hindered.

FIG. 19 shows an example in which a flange 72 that holds the edge of the housing 61 is provided at the end of the top oil 63. Even if the top oil 63 moves in the axial direction due to some force action, the heel 72 is blocked by the edge and cannot move. In either case, the top oil 63 can be reliably prevented from falling off by attaching a simple mechanism.

FIG. 20 is a cross-sectional view showing a state in which the locking mechanism 66 of the present embodiment is applied to the dynamic pressure gas bearing 7 using the bump oil 73.

The locking mechanism 66 of the present embodiment is not limited to the case where the spring oil of the present invention is used, and as shown in FIG. Needless to say, it can also be used in a bearing device using fufu oil.

[0061] Further, only one locking mechanism 66 needs to be arranged in the bearing housing 61, and a plurality of locking mechanisms are installed at equal intervals, and the support rigidity is adjusted. As shown, locking mechanisms may be placed at appropriate intervals to cause unequal support rigidity, for example, to suppress vibrations, or to respond to changes in starting load and rotating load. .

Example 10

FIG. 22 is a cross-sectional view schematically showing a dynamic pressure gas bearing of the tenth embodiment, and FIG. 23 is a plan view of a spring oil used in this embodiment.

The dynamic pressure gas bearing 8 of this embodiment uses a spring oil 82 as shown in FIG. The spring oil 82 is formed by arranging the tongs 86 formed with slits on three sides of the rectangle on the entire surface.In the figure, three rows of tongs 86 of the same shape are arranged in the width direction. Of course, there are 15 rows! /, But it is not limited to these arrangements.

The spring oil 82 is inserted inside the bearing housing 81, and the top oil 83 having a cylindrical shape is fixed to the inner wall by the locking mechanism 84, and the rotary shaft 85 is inserted into the top oil 83, and the bearing 8 Is configured.

[0063] Since the spring oil 82 is arranged along the top oil 83, the tongue 86 extends tangentially from the curved surface of the spring oil 82 and hits the inner wall of the housing 81 to act as a panel. Then, a support rigidity is given to the rotary shaft 85 through the top oil 83. The tongue 86 not only exhibits a panel action, but also slides on the inner wall surface of the housing 81 when pressed, and thus has the ability to suppress vibration by friction damping during high-speed rotation. The tongue 86 is simply formed by cutting the spring oil 82, and unlike the leaf oil, it does not need to be plastically deformed. The incision can be made easily and with high precision by etching in the same manner as the slit of the spring oil used in Example 1 or the like.

FIG. 24 and FIG. 25 are drawings showing an example in which the shape of the tongue formed on the spring oil 82 is changed.

The spring oil 82 in FIG. 24 is an example in which the width of the rectangular tongue is changed in the axial direction. The central tongue 87 is formed wider, and the width of the tongues 88 at both ends is smaller than the central one. By incorporating such a spring oil 82, it is possible to provide a strong support strength at the end portion in the axial direction of the bearing and a weak support rigidity at the end portion, thereby preventing the rotation shaft from hitting one side.

The spring oil 82 in FIG. 25 has a triangular tongue formed by slitting two sides of the triangle, and the central tongue 89 has a larger triangle than the tongue 90 at both ends. The triangular tongs 89 and 90 support the more the high-speed rotation, as the effective support position of the tongs widens toward the base side of the tongue as the distance between the flange 82 and the housing 81 becomes shorter. It has a characteristic that the rigidity increases rapidly. In addition, since the tongue 90 is short in the portion close to the end of the bearing and cannot be strongly pressed against the housing 81, it has a function of preventing the one piece contact where the supporting rigidity is weak.

Example 11

FIG. 26 is a plan view of the spring oil used in the dynamic pressure gas bearing of the eleventh embodiment. The spring oil used in this embodiment has a slit portion with a wide cut-off shape, and is adjacent to the spring oil. The distance force to the ridgeline of the slit to be changed varies depending on the distance of the end force of the oil flat plate, so that the rigidity is changed.

[0067] For example, as shown in FIG. 26 (a), when spring oil 91 in which a wide slit 92 having a shape in which a triangle or a circle protrudes from one side of the slit is juxtaposed as shown in FIG. As the projection of the center of the slit comes into contact with the inner wall of the housing and becomes one of the fulcrums before it spreads, a relatively long beam is formed at the center, and there is no effective beam on the side, causing rotation. The shaft should be supported at the center with relatively weak rigidity become. In this way, it can be configured such that the rigidity changes greatly in the axial direction of the bearing.

In addition, when the rotating shaft rotates and the top oil spreads, the protruding shape in the slit gradually contacts the inner wall of the housing step by step, finally increasing the support rigidity and finally rotating at high speed. Since the elastic beam is pressed against the wall, it becomes extremely strong and rigid, and the change in rigidity accompanying rotation is large.

[0068] Further, as shown in FIG. 26 (b), when the slit shape is a wide slit 93 such as a semicircular shape, a bow shape or a trapezoidal shape, the end of the wide slit 93 is the inner wall of the housing while the top oil does not spread. A force with which a long span beam is formed as a fulcrum in contact with the surface and a relatively weak rigidity is given. Since the elastic beam does not act at the center, there is a stiffness distribution in the axial direction. Furthermore, as the top oil spreads, the center position of the slit comes into contact with the inner wall of the housing, and the short span beam becomes effective and the rigidity increases, and the rigidity changes with rotation. The rigidity distribution and the change state vary depending on the shape of the slit.

Therefore, it is possible to design the supporting rigidity by selecting the wide slit 94 having an appropriate shape as required as shown in FIG. 26 (c).

Example 12

FIG. 27 is a cross-sectional view schematically showing a dynamic pressure gas bearing of a twelfth embodiment.

The dynamic pressure gas bearing 9 of this embodiment uses a double spring oil. A polygonal spring oil 96 is inserted into the housing 95, a polygonal spring oil 97 having the same number of angles is inserted inside, and a top oil 98 is further inserted.

The angular force of the inner spring oil 97 is preferably arranged so that it hits the central portion of the elastic spring 96 of the outer spring oil 96.

[0070] If both the inner and outer spring oils are opened at the same circumferential position and fixed together using the locking mechanism described above, the positional relationship can be defined reliably. This comes out.

In addition, in order to ensure the arrangement of the spring oil, the inner and outer spring foils are built on one elastic metal plate and rolled into a double and set in the housing. You may do it. Further, one end of the spring oil may be fixed to the inner wall of the knowing. Needless to say, the spring oil is not limited to double, but may have a multiple structure with an appropriate number of spring foil layers.

[0071] When the multi-layer structure is used, the rigidity increases as the top oil spreads and the action of the outer spring oil becomes apparent. Therefore, the bearing is manufactured so that it can be supported with moderate rigidity up to high speed rotation. can do.

In addition, since the frictional motion occurs where the spring oil comes into contact with each other, the vibration of the bearing can be attenuated.

Example 13

[0072] FIG. 28 is a cross-sectional view showing a dynamic pressure gas bearing in which a plurality of spring oils are arranged so as to overlap each other and the vibrations of the oils are rubbed together to attenuate the vibration of the bearings. It is.

Four spring oils 100 are arranged so that one end is fixed to the inner wall 99 of the nosing at equal intervals, and overlap each other half, and the top oil 101 is inserted therein.

When the rotating shaft vibrates, the top oil 101 acts on the spring oil 100 and slides to each other, so that a frictional resistance is generated and the vibration can be attenuated.

Example 14

FIG. 29 is a cross-sectional view schematically showing a dynamic pressure gas bearing of the fourteenth embodiment.

The dynamic pressure gas bearing of the present embodiment was assembled so that the inner hole cross section of the bearing housing 102 was formed into a polygon, and the slit of the spring oil 103 was positioned at the ridgeline 105 formed at the apex of the polygon. Is.

The number of ridge lines in the polygonal cylinder formed by the inner bore of the Uzing 102 is twice the number of ridge lines of the polygon cylinder formed by the spring oil 103, and the elastic beam formed by the spring oil 103 makes the ridge line of the housing 1 It is preferable to place them one by one.

[0074] When such an arrangement is adopted, a gap formed behind the elastic beam is increased, and a sufficient flow of cooling air can be secured, so that a usable high-speed rotation range is expanded. Also, spring fo The seal 103 is securely fixed by aligning the slit position with the ridge line 105 of the nosing so that unnecessary displacement does not occur. Further, since the back of the elastic beam is large, the range having the inherent elasticity with respect to the wide force S of the top oil 104 is expanded.

In each of the above embodiments, a gas bearing that can be used in the air is taken up. However, each of the above structures can be used in oil or water as it is. Since fluid bearings using oil or water are used at a relatively low temperature, a thin flat plate can be formed of a polymer material such as tetrafluoroethylene instead of metal.

Claims

The scope of the claims

[1] A spring foil made of a thin flat plate with a plurality of slits is mounted on the inner wall of the bearing housing, a top oil is arranged inside the spring oil, and a rotating shaft is inside the top foil. To form a polygonal cross section having a large number of elastic beams in contact with the inside of the inner wall by bending force S at a position where the rigidity of the spring oil is small, and the elastic beams are used to form the polygonal cross section through the top oil. A foil-type hydrodynamic bearing characterized by inertially supporting the rotating shaft.

[2] The spring oil forms a slit in a direction substantially parallel to the axis of the rotating shaft when mounted in the bearing housing, and the strength of the elastic beam generated between adjacent slits is determined by the slit length. 2. The fill type hydrodynamic bearing according to claim 1, wherein the adjustment is made based on the slit interval.

[3] The spring oil is formed with slits in a direction substantially parallel to the axis of the rotary shaft when mounted in the bearing housing, and the width of each of the slits is appropriately determined to determine the width of the rotary shaft. The foil type hydrodynamic bearing according to claim 1, wherein the support rigidity in the circumferential direction of the is adjusted.

[4] The spring oil should have at least two stages of rigidity generated by the slit so that weak rigidity is applied at the initial stage of rotation of the rotary shaft and strong rigidity is applied at the normal rotation state. The foil type hydrodynamic bearing according to claim 2 or 3.

[5] The spring oil is characterized in that the rigidity is changed by making the slit into a thick cut shape so that the distance to the ridgeline of the adjacent slit differs depending on the distance from the end of the flat plate. The foil type hydrodynamic bearing according to claim 2 or 3.

[6] The foil type according to claim 2 or 3, wherein the slit comprises a slit formed in close contact in parallel, and a plurality of ridge line portions in contact with the inner wall of the bearing housing share the pressing force. Hydrodynamic bearing.

[7] The spring oil covers a slit parallel to the axis of the rotation shaft, and forms a slit parallel to a side end line of the spring oil, thereby allowing the elastic beam to move in the direction of the rotation axis. The foil type hydrodynamic bearing according to claim 2 or 3, wherein the hydrodynamic bearing is divided into two parts.

[8] In addition to the slit parallel to the axis of the rotating shaft, the spring oil is added to the elastic beam. A plurality of slits parallel to the side end line of the spring oil are formed at the center of the spring oil so that the spring oil deforms along the aspect of the top oil and comes into surface contact. 2 or 3 foil type hydrodynamic bearing.

9. The foil-type hydrodynamic bearing according to claim 2, wherein the spring oil is formed by arranging slits having the same shape at equal intervals.

10. The foil type hydrodynamic bearing according to claim 2, wherein the spring oil is formed by forming a plurality of slits from a side end of the oil toward a center line.

11. The bearing housing is assembled such that a cross section of the inner hole of the bearing housing is formed in a polygon and the slit of the spring oil is positioned at the apex of the polygon.

The foil-type hydrodynamic bearing according to any one of 9 and 10.

12. The foil type hydrodynamic bearing according to any one of claims 1, 2, 3, and 9, characterized in that the spring oil is wound around the top oil in a multiple manner.

[13] The flat plate force is applied to the remaining side except for the bottom side by the slit. The tongs projecting in the tangential direction of the spring foil foil form a plurality of elastic beams in contact with the inner wall, and the top oil is formed by the elastic beams. A foil-type hydrodynamic bearing, characterized in that the rotating shaft is elastically supported via a shaft.

[14] The foil-type hydrodynamic bearing according to claim 13, wherein the tongue has a shape that becomes narrower as the bottom force is separated.

[15] A stop wall standing up from an inner wall surface is formed at the position of the inner wall of the housing where both ends of the top oil come into contact, and a dug having a triangular cross section is formed on the front surface of the stop wall. 14. A structured locking mechanism, wherein the top oil is stretched between the two retaining walls to be inserted and fixed.

The foil type hydrodynamic bearing according to any one of!

16. The foil-type hydrodynamic bearing according to claim 15, wherein the digging is deeper on the inlet side in the rotational direction of the bearing than on the outlet side.

[17] A plurality of pairs of the locking mechanisms are provided, and the top foil is logarithmized in the circumferential direction. 17. The oil-type hydrodynamic bearing according to claim 15 or 16, wherein the oil-type hydrodynamic bearing is divided into the same number as that of the hydraulic fluid.

18. The oil-type hydrodynamic fluid according to claim 15 or 16, wherein the locking mechanism is provided with a stopper that prevents the top foil from moving in the width direction on a side surface of the stopper wall. bearing.

[19] A locking mechanism formed by forming a stop wall rising from the inner wall surface at the position of the inner wall of the housing where both ends of the top oil come into contact, and forming a dug with a triangular cross section on the front surface of the stop wall A top oil locking mechanism for a foil-type hydrodynamic bearing, wherein the top oil is stretched between the surfaces of the stop wall and is inserted and fixed.

[20] A spring oil having a thin flat plate force provided with a plurality of slits, the slit being formed in a direction parallel to the axis of the rotating shaft when the spring oil is mounted in the bearing housing When the spring oil is attached to the bearing housing, the foil is bent at the position of the slit to form an elastic beam between the slits to form a cylindrical shape having a polygonal cross section. Spring oil for hydrodynamic bearings.

21. The spring oil for a foil-type hydrodynamic bearing according to claim 20, wherein the spring oil is formed by arranging slits having the same shape at equal intervals.

[22] A spring plate oil that has a flat plate force with a plurality of tongs with a shape that separates the remaining sides excluding the bottom by slits, and is formed on the inner wall of the bearing housing along the outside of the top oil. A spring foil for a foil-type hydrodynamic bearing, wherein when mounted, the tongue protrudes tangentially from the spring oil.

[23] The oil motion according to claim 9, wherein a slit length ratio, which is a ratio of a slit length of the slit to a length in a short direction of the spring oil, is 80% or more and 90% or less. Pressure fluid bearing.

24. The oil-type hydrodynamic bearing according to claim 23, wherein the slit length ratio is 80% or more and 85% or less.

[25] The degree of bending deformation that the spring oil receives is determined by the slit and the slit. If the elastic beam formed between the slits adjacent to the elastic beam is distributed, the ratio of the bending deformation of the elastic beam out of the bending deformation of the spring oil is 15% or less. The foil type hydrodynamic bearing according to claim 9.

26. The foil-type hydrodynamic bearing according to claim 9, wherein a groove width of the slit is 1.0 times or more a thickness of a thin flat plate forming the spring oil.

[27] Mount a spring oil made of a thin plate with a plurality of slits arranged in parallel on the inner wall of the bearing housing in parallel to the winding direction of the oil, and place a top foil inside the spring oil. A rotating shaft is disposed inside the top oil, and the spring oil is bent at a position with small rigidity to form a polygonal cross section having a number of inertial beams in contact with the inside of the inner wall. A foil type hydrodynamic bearing, wherein the rotary shaft is supported by inertia through oil.

[28] The spring oil is formed with slits in a direction substantially parallel to the axis of the rotary shaft when mounted in the bearing housing, and the width of each of the slits is appropriately determined to thereby determine the rotary shaft. 28. The foil-type hydrodynamic bearing according to claim 27, wherein the support rigidity of the foil is adjusted in the circumferential direction.

[29] A locking wall formed by forming a stop wall with an inner wall force rising at the position of the inner wall of the housing where both ends of the top oil come into contact, and forming a dug with a triangular cross section on the front surface of the stop wall 28. A foil-type hydrodynamic bearing according to claim 27, further comprising a mechanism, wherein the top oil is inserted between the surfaces of the stop wall so as to be inserted and fixed.

[30] A spring oil composed of a thin flat plate provided with a plurality of slits, wherein the slits are arranged side by side in a direction parallel to the axis of the rotary shaft when the spring oil is mounted in the bearing housing. When the spring oil is attached to the bearing housing, it is bent at the position of the slit to form an elastic beam between the slits to form a cylindrical shape having a polygonal cross section. Spring oil for foil type hydrodynamic bearings.

31. The spring oil for a foil-type hydrodynamic bearing according to claim 30, wherein the spring oil is formed by arranging slits having the same shape at equal intervals. Corrected paper (, The spring oil further has a plurality of slits parallel to the side end line of the spring oil, and when the spring oil is attached to the bearing housing, it follows the curved surface at the position of the slit. 32. The spring oil for a foil-type hydrodynamic bearing according to claim 30, wherein the spring oil is deformed and brought into surface contact.