JP2955134B2 - Squeeze film damper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a squeeze film damper applied to a bearing of a rotating machine or a mounting portion of a structure.

[0002]

2. Description of the Related Art A squeeze film damper is installed outside a bearing of a gas turbine or a bearing of a compressor, and performs a vibration damping function.

FIG. 4 is a longitudinal sectional view showing an example of such a conventional squeeze film damper. As shown in this figure, a plurality of arc-shaped bearing pads (102) are arranged around a rotating shaft (101) for driving and rotating with a gap (103) therebetween. )
Are each overlapped with an arc-shaped damper block (104) via a pivot (105). An annular support sleeve (1) having an oil passage (107) is formed on the inner periphery of an annular bearing housing (106) for housing the bearing pad (102) and the damper block (104).
08) are integrally fitted, and the damper block (104) is supported on the support sleeve (108) via an elastic pin (109). An oil supply pipe (110) connected to a pressure oil supply source (not shown) communicates with an oil passage (111) formed in the bearing housing (106), and is connected to the support sleeve (108) and the damper block (104). (103) between the rotating shaft (101) and the bearing pad (102) through the gap (112) of the shaft and the oil passage (113) formed in the damper block (104).
To each of these gaps (103),
An oil film is formed on (112). Excess oil is supplied to the oil drain pipe (1) connected to the lower end of the bearing housing (106).
14) to the outside.

Accordingly, since an oil film functioning as a damper is formed in the gap (112) outside the oil film as a bearing formed in the gap (103), the rotating shaft (101)
Radial vibrations generated in the motor can be easily attenuated, and stable rotation can be maintained. The elastic pin (10
9) is elastically deformed by the radial load applied to the rotating shaft (101), and the oil film in the gap (112) is removed by the rotating shaft (10).
Hold concentrically with 1).

As described above, the squeeze film damper has a squeezing effect of oil, that is, a viscous incompressible oil between two surfaces has a relative speed in a direction of increasing or decreasing a gap between the two surfaces. This is a vibration attenuator that utilizes the effect of generating a damping force according to the speed when moving.
This attenuation is enhanced when the gap between the surfaces is narrowed, so that there is a characteristic that a large attenuation can be obtained even with a relatively small size.

[0006]

In order to generate the squeeze effect, a viscous incompressible fluid such as oil is required, but an oil supply system is required to supply the oil. Further, even if an attempt is made to seal the oil with a normal sealing device, the oil cannot be completely sealed.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, the present invention provides an annular damper movable member fixed to the outer ring of a rolling bearing or an outer periphery of a bearing pad of a slide bearing; A squeeze film damper comprising: a damper support member that surrounds the outer periphery with a gap therebetween and supplies damper oil to the gap; and an elastic diaphragm that shields the gap from the outside; In addition to the above, a fin-shaped projection is provided inside an oil chamber formed inside the damper support member, and a throttle hole communicating the gap with the oil chamber is formed. This is to propose a film damper.

[0008]

According to the present invention, an elastic diaphragm for shielding the gap of the squeeze film damper from the outside is provided.
The hydraulic oil sealed in the gap is prevented from leaking without hindering movement due to vibration, and environmental pollution is suppressed.

Further, by supplying the working oil from the oil reservoir to the gap via the throttle hole, the vibration damping effect is enhanced. Further, by providing the fin-shaped protrusions in the oil reservoir, heat radiation from the hydraulic oil is promoted.

[0010]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention. In the figure, (1) is the inner ring of the ball bearing, (2) is the ball,
(3) similarly shows the outer rings. An annular inner damper movable member (4) is fixed to the outer periphery of the bearing outer ring (3), and an elastic diaphragm (6) is sandwiched on the outer periphery of the inner damper movable member (4). An outer damper movable member (5) is fixed with a screw (7). A damper support member (10) surrounds the outer periphery of the outer damper movable member (5) through gaps (8a) and (8b), and the gap (8a)
Form an oil sump (9).

At one end of the damper support member (10), a thrust receiver (11) is provided with a seal ring (12) interposed therebetween.
Is screwed. The other end of the damper support member (10) and the end of the thrust receiver (11) sandwich the both side edges of the diaphragm (6), and hold the pressing member (13).
a) and (13b) are screwed in so that the diaphragm (6) shields the gaps (8a) and (8b) and the oil reservoir (9) from the outside. Hydraulic oil is sealed in the gaps (8a) and (8b) and the oil reservoir (9).

The oil stored in the oil sump (9) is supplied to gaps (8a) and (8b) between the damper support member (10) and the outer damper movable member (5). The vibration force generated by a rotating body (not shown) supported by the inner ring (1) of the ball bearing is generated by the inner ring (1), the ball (2), the outer ring (3), the inner damper movable section (4), and the outer damper movable section. (5), gap (8a),
Although the vibration is transmitted to the damper support portion (10), the vibration is attenuated due to the squeezing effect of the oil in the gaps (8a) and (8b) during transmission. Note that the ball bearing portion of this embodiment is lubricated only with a solid lubricant, and no oil is used.

In this embodiment, since the oil reservoir (9) and the gaps (8a) and (8b) have a sealed structure completely shielded from the outside by the diaphragm (6), the hydraulic oil leaks to the outside. No lubricating oil is used in the ball bearings, so that the environment is not polluted. Therefore, no refueling system is required. However, when the energy required for vibration damping is so large that the heat cannot be released only by heat transfer, the oil supply for supplying oil from the outside is provided in the damper support member (10), so that the forced oil supply can be performed.

The elastic membrane (6) is provided with an appropriate slack so as not to hinder movement due to vibration.
Depending on the type of the elastic body, the elastic body is deformed in a wave shape in advance to facilitate the deformation. The thrust receiver (11) screwed into the damper support member (10) receives thrust. Oil leakage due to the screwing is sealed by a seal ring (12).

Since the squeeze film damper is used to attenuate the vibration, it is sufficient that the clearance between the squeeze surfaces is about 10 times the generated vibration. That is, since the movable range is very narrow, about 10 times the vibration, in this embodiment, the oil is sealed by using an elastic film which can freely deform without interrupting the vibration.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the present invention. In this figure, the same parts as those in the first embodiment described with reference to FIG. 1 are denoted by the same reference numerals to avoid redundancy, and detailed description is omitted.

In this embodiment, an oil reservoir is formed inside the damper support. That is, the damper support member (3)
0) and the thrust receiver (31) screwed into this form a damper support, and form an oil reservoir (29). Then, the oil stored in the oil storage chamber (29) passes through the throttle holes (35) and the gaps (8a), (8b).
It is supplied to. In this embodiment, a radiating fin (34) is provided inside the oil reservoir (29) in order to facilitate heat radiation at the time of sealing.

In this embodiment, the inner ring (1) of the ball bearing is used.
Of the ball (2), the outer ring (3), the inner damper movable part (4), the outer damper movable part (5), and the clearance (8)
a), during transmission to the thrust receiver (31) and the damper support member (30), the squeezing effect of the oil in the gaps (8a) and (8b) and the movement of the oil through the throttle hole (35). The vibration is attenuated by the flow loss.

Since the squeeze film damper is also a mechanism for converting vibration energy into heat energy, it is necessary to consider the cooling of the hydraulic oil when sealing it. In this embodiment, since the fin-shaped projections (radiation fins) (34) are provided in the oil reservoir (29), heat exchange is promoted, and the cooling effect of the working oil is enhanced.

In this embodiment, a throttle hole (35) for communicating the squeeze film damper with the oil sump chamber (29).
The damping effect can be enhanced and adjusted to an optimum state by appropriately setting the number and diameter of the throttle holes (35). When the spring action and the damping action of the squeeze film are tuned in accordance with the vibration characteristics of the supported member, the throttle hole increases the degree of freedom of the size of the gap between the squeeze surfaces, and the hydraulic oil fills the throttle hole. When passing through, the damping effect is superimposed and generated.

FIG. 3 is an overall layout diagram showing a third embodiment of the present invention. The pipe (41) is supported by the partition (42), and is also supported by a partition plate (43) via a squeeze film damper (40) on the way. Piping (4
In 1), a vibration is generated by the fluid flowing inside and outside the pipe.
Attenuate with 0). It should be noted that the same effect can be obtained by replacing the structure generating vibration instead of the pipe (41).

[0022]

According to the present invention, since the elastic diaphragm which shields the gap of the squeeze film damper portion from the outside is provided, the leakage of the hydraulic oil sealed in the gap is prevented without obstructing the movement due to the vibration. Environmental pollution is suppressed.

Further, by supplying the working oil from the oil reservoir to the gap through the throttle hole, the vibration damping effect is enhanced. Further, by providing the fin-shaped protrusions in the oil reservoir, heat radiation from the hydraulic oil is promoted.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the present invention.

FIG. 3 is an overall layout diagram showing a third embodiment of the present invention.

FIG. 4 is a longitudinal sectional view showing an example of a conventional squeeze film damper.

[Explanation of symbols]

 (1) Inner ring of ball bearing (2) Ball of ball bearing (3) Outer ring of ball bearing (4) Inner damper movable member (5) Outer damper movable member (6) Diaphragm (7) Screw (8a), (8b) Gap (9) Oil reservoir (10) Damper support member (11) Thrust receiver (12) Seal ring (13a), (13b) Holding member (29) Oil reservoir chamber (30) Damper support member (31) Thrust receiver (34) ) Heat radiation fins (35) Restricted holes (40) Squeeze film dampers (41) Piping (42) Partition walls (43) Partition plates

Continuation of the front page (72) Inventor Ishiko Masada 5-717-1 Fukahori-cho, Nagasaki-shi Mitsubishi Heavy Industries, Ltd. Nagasaki Research Laboratories (56) References JP-A-48-67640 (JP, A) Real-life Sho-56 -1443619 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16C 27/00

Claims (2)

(57) [Claims] 1. An annular damper movable member fixed to an outer periphery of an outer ring of a rolling bearing or a bearing pad of a slide bearing, and an outer periphery of the damper movable member is surrounded by a gap, and damper oil is supplied to the gap. A damper support member,
A squeeze film damper comprising an elastic diaphragm for shielding the gap from the outside. 2. A fin-like projection is provided inside an oil chamber formed inside said damper support member, and a throttle hole communicating said gap with said oil chamber is formed. Item 4. A squeeze film damper according to Item 1.