JPH04327022A - Static pressure bearing testing device - Google Patents

Abstract

PURPOSE:To provide a static pressure bearing testing device which can seize a characteristic of a static pressure bearing alone with accuracy. CONSTITUTION:An impeller 3 of a turbine 1 fixed to a casing 2 is supported by a shaft 4 housed in the casing 2. Static pressure bearings 7, 8 which rotatably journal supported portions 5, 6 of the shaft 4 through a fluid pressure is arranged in the casing 2. A thrust flange 18 is formed on a required portion of the shaft 4. A thrust bearing 20 which holds both ends of the thrust flange 10 through the fluid pressure is arranged in the casing 2. A radial loader which gives a fluid pressure to the shaft 4 between the static pressure bearings 7, 8 in a radial direction is provided on a required portion of the casing 2.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrostatic bearing testing device.

0002

[Prior Art] Currently, pump-type liquid rocket engines are used in the main engines of space shuttles, etc., but one of the major factors that hinders the longevity of the pump-type liquid rocket engines is the lack of turbo pump bearings. There is a wear problem.

[0003] Therefore, as a method to solve this problem,
Consideration has been given to changing the bearing from a conventional ball bearing to a non-contact hydrostatic bearing.

0004

[Problem to be Solved by the Invention] In order to design a hydrostatic bearing for the turbo pump of such a pump type liquid rocket engine, it is necessary to obtain basic data of the hydrostatic bearing.
Until now, there has been no testing equipment that can accurately determine the characteristics of hydrostatic bearings.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a hydrostatic bearing testing device that can accurately grasp the characteristics of only a hydrostatic bearing.

[0006]

[Means for Solving the Problems] The present invention comprises a shaft which is housed in a casing and has a turbine impeller connected to one end thereof, and a static shaft which rotatably supports the shaft at a plurality of locations in the axial direction by fluid pressure. A static pressure is created by applying fluid pressure from the radial direction to the shaft between a pressure bearing, a thrust bearing that holds both axial end surfaces of a thrust collar formed at a predetermined position of the shaft by fluid pressure, and the hydrostatic pressure bearing. This invention relates to a hydrostatic bearing testing device characterized by comprising a radial loader that adjusts the amount of load applied to the bearing.

[0007]

[Operation] Therefore, in the present invention, since the shaft is supported without solid contact with the casing side, it is possible to accurately test the characteristics of only the hydrostatic bearing.

[0008]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 to 4 show one embodiment of the present invention, and the hydrostatic bearing testing device described below is an example in which liquid hydrogen, which is a cryogenic propellant for rockets, is used as the bearing fluid.

In the figure, reference numeral 1 indicates a turbine fixed to a casing 2, and an impeller 3 of the turbine 1 is integrally formed with one end of a shaft 4 housed within the casing 2.

Supported portions 5 and 6 having convex cross sections are formed at a plurality of locations (two locations in the illustrated example) in the axial direction of the shaft 4 over the entire circumferential direction of the shaft 4. The parts 5 and 6 are rotatably supported by static pressure bearings 7 and 8, which are test bearings provided on the casing 2 side.

That is, the hydrostatic bearings 7 and 8 are fitted onto the outer peripheries of the supported parts 5 and 6 with a required clearance, and liquid hydrogen introduction holes formed at predetermined positions in the casing 2 are provided. The supported parts 5 and 6 of the shaft 4 are supported in a non-contact manner by the fluid pressure of the liquid hydrogen 13 introduced from the chambers 9 and 10 to the clearance via the introduction channels 11 and 12.

Further, the fluid pressure between each of the hydrostatic bearings 7, 8 and the supported parts 5, 6 of the shaft 4 is transferred to the casing 2 through pressure detection passages 14, 15 formed on the casing 2 side. The pressure is detected by external pressure gauges 16 and 17.

Furthermore, on the other end side of the shaft 4, there is a
As shown in an enlarged view in FIG. 4, a thrust collar 18 whose outer periphery has a substantially T-shaped cross section is formed all around the shaft 4 in the circumferential direction, and this thrust collar 18 and a holding chamber formed around it. 19 constitutes a thrust bearing 20 for supporting the thrust load generated on the shaft 4.

That is, the thrust bearing 20 is operated by the fluid pressure of the liquid hydrogen 13 introduced from the liquid hydrogen introduction chamber 21 formed at a predetermined position in the casing 2 to the holding chamber 19 via the introduction channels 22 and 23. The end surfaces 18a and 18b of the thrust collar 18 can be held in a non-contact state.

[0016] Also, at a position near the other end of the shaft 4,
A non-contact displacement meter 24 facing the other end of the shaft 4
is arranged so that displacement of the shaft 4 in the axial direction can be monitored.

[0017]Furthermore, at required positions of the casing 2,
A radial which can adjust the load amount of the hydrostatic pressure bearings 7 and 8 by applying fluid pressure of liquid hydrogen 13 to the shaft 4 between the hydrostatic pressure bearings 7 and 8 from the radial direction of the shaft 4. A loader 25 is provided.

That is, the radial loader 25 has a hollow rod 28 which is biased toward the shaft 4 by a compression spring 27 via a holding member 26, and a hollow rod 28 which is biased toward the shaft 4 by a compression spring 27 via a holding member 26. It consists of a liquid hydrogen introduction chamber 31 communicating with the hollow part 30 of the hollow rod 28 and a pressure chamber 32 formed at the lower end of the hollow rod 28. The fluid pressure of the liquid hydrogen 13 introduced into the pressure chamber 32 through the shaft 4 can be applied to the shaft 4.

Non-contact displacement meters 33, 34, 35 are provided at the upper position of the hollow rod 28, at the side position of the shaft 4, and at the lower position of the shaft 4, respectively.
are arranged, so that the vibration characteristics, rigidity, stability, etc. of the shaft 4 can be investigated based on the amount of displacement in each direction detected by the displacement meters 33, 34, 35.

[0020] Furthermore, the rotational speed of the shaft 4 can also be measured using a separately provided tachometer (not shown).

Furthermore, each of the liquid hydrogen introduction chambers 9 and 10 described above
, 21, 31 are supplied with liquid hydrogen 13 from external equipment (not shown) via liquid hydrogen introduction lines 36, 37, 38, 39.
The hydrostatic bearings 7, 8, and
The liquid hydrogen 13 used in the radial loader 25 and thrust bearing 20 is transferred from liquid hydrogen discharge chambers 40, 41, 42, 43, 44, 45 formed at required positions to liquid hydrogen discharge lines 46, 47, 48, respectively. 49, 50, 51, 55
It is designed to be discharged out of the casing 2 at any time via.

In the figure, 52 is a valve, 53 is an orifice, and 54 is a lavence seal.

The operation will be explained below.

Liquid hydrogen 13 is introduced into the liquid hydrogen introduction chambers 9 and 10 of the hydrostatic bearings 7 and 8 through the liquid hydrogen introduction lines 36 and 38.
When the liquid hydrogen 13 is supplied, the liquid hydrogen 13 is fed between the hydrostatic bearings 7, 8 and the supported parts 5, 6 of the shaft 4 through the introduction channels 11, 12, and the supported parts 5, 6 are filled with fluid. The new liquid hydrogen 13 is supported in a floating state from the hydrostatic bearings 7 and 8 by pressure, and the liquid hydrogen discharge chamber 40,
41, 43, 44 and liquid hydrogen discharge line 4.
6, 47 and 49, 50 to the outside of the casing 2.

Furthermore, when liquid hydrogen 13 is supplied to the liquid hydrogen introduction chamber 21 of the thrust bearing 20 through the liquid hydrogen introduction line 39, the liquid hydrogen 13 passes through the introduction channels 22 and 23 to the shaft of the casing 2 and the thrust collar 18. Both end faces in the center direction 1
8a and 18b, respectively, and the thrust collar 1
Both end surfaces 18a and 18b of 8 are held in a floating state from the casing 2 side, and new liquid hydrogen 1 is sequentially supplied.
3 flows into the liquid hydrogen discharge chamber 45 and is discharged from the liquid hydrogen discharge line 51 to the outside of the casing 2.

At this time, a thrust load is generated on the shaft 4 due to an imbalance in the pressure distribution of the liquid hydrogen 13 used in the hydrostatic bearings 7 and 8 in the axial direction of the shaft 4, and the shaft 4 is, for example, Even if the liquid hydrogen 13 moves toward the turbine 1 side (left side in the figure) as shown in FIG. The thrust collar 18 is obstructed by the approximately T-shaped cross-sectional shape.
The fluid pressure acting on the end face 18a on the turbine 1 side increases, generating a force that pushes the shaft 4 back in the opposite direction to the thrust load, and the thrust collar 18 is pushed back to a position where it is out of contact with the casing 2 side. is retained.

The balance function of the thrust bearing 20 with respect to the thrust load is as shown in FIG.
The thrust collar 18 acts in the same way when a thrust load is generated toward the opposite side (the right side in the figure), and also acts in the same way on the thrust load generated when the turbine 1 is driven, which will be described later. It will always be maintained in a non-contact state.

Furthermore, when the liquid hydrogen 13 is supplied to the liquid hydrogen introduction chamber 31 of the radial loader 25 through the liquid hydrogen introduction line 37, the liquid hydrogen 13 is passed through the communication hole 29 and the hollow part 30 of the hollow rod 28, and is then pressurized. The fluid pressure in the pressure chamber 32 is applied to the shaft 4 and a load is applied to the hydrostatic bearings 7 and 8.

At this time, the liquid hydrogen 1 in the pressure chamber 32
3 leaks from the boundary with the shaft 4 due to the new liquid hydrogen 13 that is successively supplied, so the lower end of the hollow rod 28 rises slightly with respect to the shaft 4 and is in a non-contact state.

The liquid hydrogen 13 leaked from the pressure chamber 32 flows into the liquid hydrogen discharge chamber 42 and flows into the liquid hydrogen discharge line 48.
is discharged from the casing 2.

Next, a driving gas such as hydrogen gas is supplied to the turbine 1 to rotationally drive the impeller 3 to rotate the shaft 4, and the radial loader 25 adjusts the load amount and the rotational speed of the turbine 1. , liquid hydrogen 13
The characteristics of the hydrostatic bearings 7 and 8 are tested while adjusting the supply pressure.

Therefore, according to the above embodiment, since the shaft 4 can be supported without making solid contact with the casing 2 side, the characteristics of only the hydrostatic bearings 7 and 8, which are the test bearings, can be accurately grasped. be able to.

The hydrostatic bearing testing apparatus of the present invention is not limited to the above-described embodiments, and fluids used in the hydrostatic bearings, radial loaders, and thrust bearings include liquid oxygen, liquid oxygen, and liquid hydrogen in addition to liquid hydrogen. Of course, a fluid such as liquefied methane may be selected, and various other changes may be made without departing from the gist of the present invention.

[0034]

[Effects of the Invention] As explained above, according to the hydrostatic bearing testing device of the present invention, the shaft can be supported without solid contact with the casing side, so the characteristics of the hydrostatic bearing can be accurately measured. can be grasped.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a view taken along arrow II-II in FIG. 1;

FIG. 3 is an enlarged view of the thrust bearing of FIG. 1;

FIG. 4 is an enlarged view of the thrust bearing in FIG. 1;

[Explanation of symbols]

1 Turbine 2 Casing 3 Impeller 4 Shaft 7 Static pressure bearing 8 Static pressure bearing 18 Thrust brim 20 Thrust bearing 25 Radial loader

Claims (1)

[Claims] 1. A shaft having one end connected to a turbine impeller and housed in a casing; a hydrostatic bearing rotatably supporting the shaft at multiple locations in the axial direction by fluid pressure; The amount of load applied to the hydrostatic bearing is adjusted by applying fluid pressure from the radial direction to the shaft between the thrust bearing, which holds both axial end surfaces of the thrust collar formed in the required position using fluid pressure, and the hydrostatic bearing. A hydrostatic bearing testing device characterized by being equipped with a radial loader.