JP3834785B2 - Hydrodynamic bearing - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydrodynamic bearing, in particular, a hydrodynamic bearing that can be used as a bearing for high-speed rotation such as a turbocharger bearing by interposing a metal foil plate in a gap between a housing (sleeve) and a rotating shaft. About.
[0002]
[Prior art]
Conventionally, as a bearing for supporting a shaft that rotates at high speed, such as a turbocharger bearing, an oil-lubricated floating bush or a dynamic pressure bearing that uses a pumping action of a fluid by providing a dynamic pressure groove between the shaft and the sleeve is known. used. However, when the lubricating oil becomes high temperature with high-speed rotation and the viscosity is lowered, the lubricating performance is lowered, and troubles such as seizure may occur. Therefore, as a hydrodynamic bearing that can be used as a high-speed rotary bearing and has high-speed stability, impact resistance, wear resistance, etc., a pin and foil (metal) are provided between the inner peripheral surface of the housing (sleeve) and the outer periphery of the shaft. A hydrodynamic hydrodynamic bearing is proposed in which foil plates) are alternately interposed and can be elastically supported using the same as a bearing surface.
[0003]
As an example of the hydrodynamic bearing, as shown in FIG. 5A, a metal foil plate 15 in which a plurality of pins 13 are fixed at an appropriate interval in the longitudinal direction is combined with a housing 12 as shown in FIG. The metal foil plate is inserted into the gap 14 between the housing 12 and the rotating shaft 11 so that the other surface side of the metal foil plate 15 faces the outer peripheral surface of the rotating shaft 11, that is, spirally. The outer end portion of 15 is fixed to a part of the inner peripheral surface of the housing 12, as shown in FIG. 7, in the gap 24 between the housing 22 and the rotary shaft 21 inserted in the housing 22, One end portion of a metal foil plate 25 provided with a corrugated spring plate 23 on the outside is fixed. As shown in FIG. 8, one end portion is placed in the gap between the housing 32 and a rotating shaft (not shown). 32 fixed to multiple locations on the inner peripheral surface and the other end in contact with the outer surface of the rotating shaft. A plurality of leaf springs 33, 33 disposed so as to project to the inner periphery inward, hydrodynamic bearing or the like of the configuration of arranging the .. circumferentially are known so that. In these bearings, the pin 13, the corrugated leaf spring 24, the leaf spring 33, and the like have a function of maintaining the metal foil 15 or the like in a spiral shape and holding air or lubricating oil as a fluid film.
[0004]
[Problems to be solved by the invention]
As shown in FIG. 6, as a method of fixing the pin 13 to the metal foil plate 15, a method of fixing the pin 13 to the metal foil plate 15 with an adhesive was taken, but workability at the time of incorporation was poor, In addition, the adhesive 10 may be interposed between the pin 13 and the metal foil plate 15 (the pin 13 and the metal foil plate 15 are not in close contact as shown in FIG. 5B). Durability, stability, or quality varies, causing problems in dimensional accuracy management. Further, the hydrodynamic bearing as shown in FIG. 7 or FIG. 8 has various problems such as complicated production and assembly and high cost.
[0005]
The present invention has been made to address the above-described problems, and an object thereof is to provide a hydrodynamic bearing using a metal foil plate that has good assemblability, improved dimensional accuracy, and excellent stability. It is said.
[0006]
[Means for Solving the Problems]
That is, in order to solve the above-described problem, the hydrodynamic bearing according to the first aspect of the present invention includes a metal foil plate circumferentially interposed in a gap between a sleeve and a shaft, and the metal foil. In the hydrodynamic bearing in which a pin fixed to one end of the plate is fitted into a hole provided in the inner peripheral surface of the sleeve, and a plurality of pins are arranged at a predetermined interval on the outer periphery of the metal foil plate,
The perpendicular to the longitudinal direction of the larger small hole section provided in the circumferential direction by a predetermined distance I write fitted by greater freedom of both end portions of the pins in the circumferential direction and the radial direction a pin holder of the plurality of pins, said sleeve Further, the metal foil plate is supported only by coming into contact with the pin.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments of the present invention will be described.
FIG. 1 is a side view showing the configuration of the hydrodynamic bearing of the present invention, and FIG. 2 is an enlarged view of a portion P in FIG. 3A is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 3B is a cross-sectional view taken along the line BB in FIG. FIG. 4 is a perspective view of a thin metal plate and pins constituting the dynamic pressure bearing.
[0008]
The hydrodynamic bearing includes a housing (sleeve) 2 attached to a fixed portion, a shaft 1, a metal foil plate 5 circumferentially interposed in a gap 4 between the sleeve 2 and the shaft 1, and the metal foil. A plurality of pins 3 arranged on the circumference of the plate 5 without being fixed in the longitudinal direction at a predetermined interval, and small holes 6a, 6a,. And pin holders 6 and 6 provided in the above. The pin holder 6 is provided with recesses 2a and 2a at both ends of a housing (sleeve, hereinafter simply referred to as a housing) 2 and fitted therein, and a cover 8 is fitted into the recesses 2a and 2a from the outside. 8 and the pin holder are fixed to the housing 2 with screws 7. Further, as shown in FIG. 4, the pins 3 arranged on the metal foil plate 5 have both ends slightly longer than the width H of the metal foil plate 5, that is, the length supported by the pin holder 6. It is as.
[0009]
A pin 9 is fixed to one end of the metal foil plate 5. On the other hand, a hole 2 b is provided in a part of the inner peripheral surface of the housing 2, and the pin 9 is fitted therein. The metal foil plate 5 is rounded so that the pins 3, 3,... Are located on the outer peripheral side, and the double helix or the pins 3, 3,. Fit as a triple helix around the circumference. Further, holes 6a, 6a,... Provided at predetermined intervals in the circumferential direction of the pin holders 6 are formed in accordance with the helical shape of the metal foil plate 5 by the number of pins 3 arranged on the metal foil plate 5. Here, both ends of the pin 3 are fitted. In this case, the diameter of the holes 6a, 6a,... Is slightly larger than the diameter of the pin 3 so that the pin 3 has a degree of freedom. In the case of this embodiment, the metal foil plate 5 has pins 3, 3,... In the holes 6a, 6a,. Is inserted.
[0010]
In the hydrodynamic bearing having the above-described configuration, the metal foil plate 5 is disposed in the housing 2 and the shaft 1 is inserted. In this case, the assembly work is performed by inserting the pin 3 into each hole 6a of the pin holder 6, 6 is fixed to the housing 2 together with the cover 8 with the screw 7, so that the workability is very good. Further, in this case, since the pins 3, 3,... Arranged on the metal foil plate 5 do not use a conventional adhesive, when a load acts on the metal foil 5, the pins 3, 3,. -Good adhesion between the metal foil plate 5, easy to ensure dimensional accuracy, and stable quality. Therefore, the metal foil plate 5 can be disposed in the housing 2 in a spiral shape and stably.
[0011]
As pointed out as a problem in the incorporation of the conventional metal foil plate 5 (see FIG. 5B), if the adhesive 10 is interposed between the metal foil plate and the pin, the dimensional accuracy is deteriorated and the rotation is reduced. Become unstable. However, by using the pin holder 6 having the holes 6a, 6a,... For the pins in the circumferential direction as in the present invention having the above-described configuration, the metal foil plate 5 and the pins 3, 3 are used as described above. Dimensional accuracy is ensured, and stability during high-speed rotation is improved. That is, when the shaft 1 rotates at a high speed as indicated by an arrow in FIG. 1, ambient air or lubricating oil is introduced between the metal foil plate 5 and the inner peripheral surface of the housing 2 to form a fluid film, and The shaft 1 is stably supported at a high pressure due to the wedge effect.
[0012]
【The invention's effect】
As described above in detail, according to the present invention, workability when the foil of the metal foil plate is incorporated into the housing is extremely improved. Further, since the dimensional accuracy of the bearing inner diameter (the innermost diameter of the foil) is improved, the stability of the hydrodynamic bearing at high speed rotation is improved.
[Brief description of the drawings]
FIG. 1 is a side view showing a configuration of a hydrodynamic bearing of the present invention using a foil.
FIG. 2 is an enlarged view of a portion P in FIG.
3A is a cross-sectional view taken along the line AA in FIG. 2, and FIG. 3B is a cross-sectional view taken along the line BB in FIG.
FIG. 4 is a perspective view of a metal foil plate and pins constituting the hydrodynamic bearing of the present invention .
FIG. 5 is a side view showing a configuration of a conventional dynamic pressure bearing using a foil.
6A is a perspective view of a metal foil plate and a pin constituting a conventional hydrodynamic bearing, and FIG. 6B is an adhesion state between the metal foil plate and a pin. It is sectional drawing when an agent interposes.
FIG. 7 is a side view showing a configuration of a conventional hydrodynamic bearing using a foil.
FIG. 8 is a side view showing a configuration of a conventional dynamic pressure bearing using a foil.
[Explanation of symbols]
1 axis 2 housing (sleeve)
2a Recess 3 Pin 4 Crevice 5 Metal foil plate 6 Pin holder 6a Hole 7 Screw 8 Cover 9 Pin

Claims (1)

A metal foil plate is circumferentially interposed in the gap between the sleeve and the shaft, and a pin fixed to one end of the metal foil plate is fitted into a hole provided in the inner peripheral surface of the sleeve, In the hydrodynamic bearing in which a plurality of pins are arranged at a predetermined interval on the outer periphery,
The perpendicular to the longitudinal direction of the larger small hole section provided in the circumferential direction by a predetermined distance I write fitted by greater freedom of both end portions of the pins in the circumferential direction and the radial direction a pin holder of the plurality of pins, said sleeve The hydrodynamic bearing is characterized in that the metal foil plate is supported only by abutting against the pin.

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