An aerostatic ultra-speed testing machine and a method of using the same

Abstract

The application provides an air-suspension super-speed testing machine and a use method thereof. The air-suspension super-speed testing machine comprises a rotor shaft, a shell is externally sleeved with the rotor shaft, a gas guide device capable of suspending the rotor shaft is arranged between the shell and the rotor shaft, the gas guide device comprises a gas guide cylinder located on a ring surface of the rotor shaft and a gas distribution ring located on two radial end faces of the rotor shaft respectively, first end covers and second end covers are arranged at two ends of the shell respectively, the first end covers and the second end covers are fixedly connected with the gas guide cylinder, the shell and the gas distribution ring, the rotor shaft is installed in a cavity composed of the gas guide cylinder and the gas distribution ring, and gaps are arranged between the rotor shaft and the gas distribution ring and the gas guide cylinder. The device has the advantages of simple structure, low cost, air-suspension design, no mechanical friction, a rotating speed of 10-20 million revolutions per minute, almost no friction in the working environment due to the air-suspension design, and increased service life.

Description

An air suspension overspeed testing machine and its usage method Technical Field

[0001] This invention relates to the field of mechanical design technology, and in particular to a stability testing device, specifically an air suspension overspeed testing machine and its usage method. Background Technology

[0002] As is well known, the electric motors used in common stability testing equipment can generally reach a maximum speed of 30,000 to 40,000 revolutions per minute. In order to increase the speed, a high-speed gearbox is used. High-speed gearboxes are characterized by high precision, have high manufacturing costs and requirements, and are used in a vacuum environment. The sealing of high-speed gearboxes is also a challenge.

[0003] With the rapid development of investment casting technology, many complex parts (such as aircraft turbine disks and compressor closed impellers) can be manufactured using investment casting technology. However, due to the complex structure of these products, traditional machining methods cannot be used, or the required machining precision cannot be met.

[0004] Especially for components that will be used in rotating structures in the future, such as impellers and turbines, rotational stability is an important factor in product performance. In order to ensure the performance of products made by investment casting, rotational stability testing is required. For example, some turbine and impeller structures operate at speeds of tens or hundreds of thousands of revolutions per minute. Without equipment that can reach this speed, it is impossible to verify their stability. It is precisely because the testing equipment itself does not have enough speed that it is impossible to verify whether the product stability meets the design requirements. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the shortcomings of the existing technology by providing an air suspension overspeed testing machine and its usage method. The equipment has a simple structure, low cost, and ingenious and reasonable structural design. Utilizing an air suspension design, there is no mechanical friction, which can increase the speed to 100,000-200,000 revolutions per minute. It is precisely because of its air suspension design and zero-friction working environment that its service life is increased.

[0006] In addition, through holes are opened in the air guide tube and air distribution plate, and plungers with capillary holes are installed. The plungers are replaceable, and different rotor shafts can be replaced according to the structure of different parts. The diameter of the capillary holes on the plungers can be adjusted in a targeted manner, making the entire equipment more widely applicable.

[0007] The reason for using a plunger instead of directly machining capillary holes on the air guide tube and air distribution plate is that it is more convenient. It is difficult to machine a cylindrical air guide tube so that the central axis of each capillary hole accurately passes through the central axis. The inlay structure makes it easier to machine, improves the overall precision of the equipment, and helps to achieve a zero-friction design for the rotor shaft.

[0008] The technical solution of the present invention is to provide an air suspension overspeed testing machine, which includes a rotor shaft, a housing fitted outside the rotor shaft, and an air guiding device between the housing and the rotor shaft that allows the rotor shaft to be suspended in the air. The air guiding device includes an air guiding cylinder located on the annular curved surface of the rotor shaft and air distribution rings located on two radial end faces of the rotor shaft. The housing has a first end cover and a second end cover at both ends, which fix the air guiding cylinder, the housing, and the air distribution rings. The rotor shaft is installed in the cavity formed by the air guiding cylinder and the air distribution rings, and there are gaps between the rotor shaft and the air distribution rings and the air guiding cylinder.

[0009] Preferably, the air guide cylinder is provided with an air passage between itself and the housing. The air passage is annular. The air guide cylinder is sleeved outside the rotor shaft. The air guide cylinder has a plurality of through holes that penetrate the inner and outer arms of the air guide cylinder in the radial direction. A plunger is provided in the through hole. The plunger has axially arranged capillary holes that face the axis of the rotor shaft. The housing has an air inlet A that communicates with the air passage between the air guide cylinder and the housing.

[0010] Preferably, the rotor shaft extends outward after passing through the first end cover and the second end cover at both ends, and the rotor shaft is a stepped shaft. The radial dimension of the rotor shaft inside the air guide tube is greater than the radial dimension extending to the outside of the end cover.

[0011] Preferably, the valve ring is fitted onto the stepped portion of the rotor shaft, with the inner plane of the valve ring parallel to the stepped end face of the rotor shaft.

[0012] Preferably, both the first end cap and the second end cap have an inwardly recessed mounting groove on the side near the air guide tube, and the air distribution ring is installed in the mounting groove.

[0013] Preferably, the valve ring has a plurality of through holes in a ring shape that penetrate both planes of the valve ring. A plunger is provided in each through hole, and the plunger has axially arranged capillary holes, which are arranged perpendicular to the stepped end face of the rotor shaft.

[0014] Preferably, both the first end cap and the second end cap are provided with an air inlet B1 and an air inlet B2 that communicate with the through hole on the air distribution ring. There are several air inlets B1 and B2, which are arranged in a ring.

[0015] Preferably, both the first end cap and the second end cap are provided with a positioning ring protruding towards the air guide cylinder on the side adjacent to the air guide cylinder.

[0016] Preferably, the second end cover is also provided with a vortex air guide plate on its side. The vortex air guide plate is fixed to the second end cover by screws. The rotor shaft extension end located on one side of the second end cover extends to the outside of the vortex air guide plate and is connected to a turbine. The vortex air guide plate is also provided with an air inlet C to provide power for the turbine rotation.

[0017] Preferably, the rotor on one side of the first end cover extends axially outward to form a test connection end for mounting the test workpiece.

[0018] The beneficial effects of adopting this technical solution are as follows: 1. The high-pressure air from the air inlet A suspends the rotor shaft at the center of the air guide cylinder, and an air layer is formed between the curved surface of the rotor shaft and the air guide cylinder, resulting in no friction. The high-pressure air from the air inlets B1 and B2 suspends the rotor between the two air distribution rings, and an air layer is provided in the end face gap, resulting in no friction. Reducing friction is the most important solution for increasing the rotational speed.

[0019] 2. By utilizing the high-pressure air at the intake port C and passing through the turbine guide plate, the high-pressure air is forced to change direction and form a vortex. The angle of the generated vortex airflow interacts with the turbine, driving the turbine to rotate and increasing the turbine speed to provide a higher rotational speed.

[0020] 3. By utilizing the capillary action on the rotor shaft, the finer the airflow within a certain range, the better its directionality. The airflow from several capillary pores has more points of application, effectively ensuring that the rotor shaft is subjected to more uniform force, without deviation, and located in the center position, preventing contact and friction with the guide tube and air distribution ring.

[0021] 4. Frictionless rotation increases the rotational speed, reaching 100,000-200,000 rpm under the action of a common industrial compressed gas compressor, thus ensuring the rotational stability of the workpiece. Attached Figure Description

[0022] Figure 1 is a schematic diagram of the structure of an air suspension overspeed testing machine.

[0023] Figure 2 is a cross-sectional view of MM in Figure 1.

[0024] Figure 3 is a schematic diagram of the three-dimensional structure of Figure 1 (I).

[0025] Figure 4 is a schematic diagram of the three-dimensional structure of Figure 1 (II). Detailed Implementation

[0026] For ease of explanation, the invention of the air suspension overspeed testing machine will be described in detail below with reference to the accompanying drawings.

[0027] As shown in Figures 1 to 4, an air suspension overspeed testing machine includes a rotor shaft 1. A housing 2 is fitted around the rotor shaft 1. An air guiding device is provided between the housing 2 and the rotor shaft 1 to suspend the rotor shaft 1. The air guiding device includes an air guiding cylinder 3 located outside the annular curved surface of the rotor shaft 1 and air distribution rings 4 located on the two radial end faces of the rotor shaft 1. Its function is to use the air guiding cylinder 3 to blow high-pressure air radially and the air distribution rings to blow high-pressure air axially, so that the rotor shaft is located in the cavity formed by the air guiding cylinder 3 and the air distribution rings 4 by the force of the high-pressure air, so that the curved surface and the end face do not contact each other, avoiding mechanical friction and affecting the rotational speed.

[0028] The shell 2 is provided with a first end cap 5 and a second end cap 6 at both ends. Of course, in order to facilitate manufacturing, the two end caps are adopted. It can also be designed as a single end cap with the other end cap being integrated with the shell. Alternatively, it can be designed as a no-end-cap design, with the cylinder made into two halves and connected by flanges, etc. These are all equivalent designs consistent with the technical solution. In order to facilitate manufacturing and installation, this technical solution is designed as a two-end-cap design. This embodiment is also described using the two-end-cap design.

[0029] The first end cap 5 and the second end cap 6 fix the air guide cylinder 3, the housing 2, and the air distribution ring 4. There are gaps between the rotor shaft 1 and the air distribution ring 4 and the air guide cylinder 3, mainly to prevent mechanical friction.

[0030] The air guide cylinder 3 is connected to the housing 2 by an air passage 7, which is annular. The air guide cylinder 3 is sleeved around the outside of the rotor shaft 1. The air guide cylinder 3 has several through holes 8 that penetrate the inner and outer arms of the air guide cylinder 3 radially. A plunger 9 is provided in each through hole 8. The plunger 9 has axially arranged capillary holes 10, which are oriented towards the axis of the rotor shaft 1. The housing 2 has an air inlet A that communicates with the air passage 7 between the air guide cylinder 3 and the housing 2. High-pressure gas enters the annular air passage through the air inlet A, and then enters the gap between the rotor shaft and the air guide cylinder through the several capillary holes 10. The uniform gas distribution through the annular air passage ensures that the pressure of each capillary hole is the same. In essence, the high-pressure gas directly acts on the rotor shaft through the capillary holes 10, thereby achieving a non-contact state between the rotor shaft and the air guide cylinder. Furthermore, the continuous entry of high-pressure gas ensures that the separation state is always maintained, achieving no mechanical friction.

[0031] The rotor shaft 1 extends outward after passing through the first end cover 5 and the second end cover 6 at both ends. The rotor shaft 1 is a stepped shaft. The radial dimension of the rotor shaft 1 inside the air guide tube 3 is greater than the radial dimension extending to the outside of the end cover. The rotor shaft needs to be driven by an external force to rotate, so it needs to extend to the outside. The stepped shaft structure is used, and the axial limit and non-contact state of the rotor shaft are achieved through the action of the air distribution ring 4 at the stepped end face.

[0032] The valve train 4 is fitted onto the stepped section of the rotor shaft 1, with the inner plane of the valve train 4 parallel to the stepped end face of the rotor shaft 1. This parallelism is primarily to provide an axial thrust and maximize the thrust without decomposing forces in other directions.

[0033] The first end cap 5 and the second end cap 6 are both provided with inwardly recessed mounting grooves 11 on the side near the air guide cylinder 3. The air distribution ring 4 is installed in the mounting groove 11. The air distribution ring 4 is provided with a plurality of through holes 8 in a ring shape, penetrating the two planes of the air distribution ring 4. A plunger 9 is provided in the through hole 8. The plunger 9 is provided with axially arranged capillary holes 10. The capillary holes 10 are arranged perpendicular to the stepped end face of the rotor shaft 1. The function of the capillary holes 10 here is the same as that of the capillary holes on the air guide cylinder, except that the position of the capillary holes on the rotor shaft is different. The high-pressure airflow flowing out of the capillary holes here blows towards the stepped end face of the rotor shaft in order to position the rotor shaft axially between the two air distribution rings to achieve no mechanical friction.

[0034] To better achieve centered, non-contact rotation of the rotor shaft, the diameter of the capillary is set to 0.25mm ± 0.05mm, the single-sided gap between the rotor shaft and the air guide is 0.05mm ± 0.05mm, and the single-sided distance between the stepped end face of the rotor shaft and the surface of the air distribution plate is 0.05mm ± 0.05mm.

[0035] The first end cap 5 and the second end cap 6 are each provided with an air inlet B1 and an air inlet B2 that communicate with the through hole 8 on the air distribution ring 4. There are several air inlets B1 and B2, which are arranged in a ring. The air distribution pipe is not a ring-shaped air passage, but each through hole on the air distribution ring is connected to an air inlet B1 or an air inlet B2. Of course, the high-pressure gas entering each air inlet B1 and air inlet B2 has the same pressure. To ensure that the gas pressure coming out of each capillary is consistent, the rotor shaft is guaranteed to be balanced.

[0036] The first end cap 5 and the second end cap 6 are each provided with a positioning ring 12 protruding towards the air guide cylinder 3 on the side adjacent to the air guide cylinder 3; this is mainly for easy fixing and positioning during installation.

[0037] The second end cover 6 is also provided with a vortex-shaped air guide plate 13 on its side. The vortex-shaped air guide plate 13 is fixed to the second end cover 6 by screws. The rotor shaft 1 extension end located on one side of the second end cover 6 extends to the outside of the vortex-shaped air guide plate 13 and is connected to a turbine 14. The vortex-shaped air guide plate 13 is also provided with an air inlet C to provide power for the rotation of the turbine 14. High-pressure gas enters through the air inlet C. Because the blades of the vortex-shaped air guide plate are located between the high-pressure gas channel and the turbine, the high-pressure gas will fill the rectification chamber after entering. Then, the high-pressure gas is evenly distributed and directionally blown out by the blades of the vortex-shaped air guide plate. Each blade has an angle. The airflow rotates and flows out through the vortex-shaped air guide plate, which blows directly onto the turbine located outside the vortex-shaped air guide plate. Since the vortex-shaped air guide plate is a component matched with the turbine, it accelerates the speed of the turbine. The turbine is installed on the extension end of the rotor shaft, thereby driving the rotation of the rotor shaft.

[0038] The rotor shaft 1 on one side of the first end cover 5 extends outward to form a test connection end 16 for mounting the test workpiece 15. The turbine drives the rotor shaft to rotate, and the other end of the rotor shaft is also provided with an extension. By mounting the workpiece to be tested, high-speed rotation can be achieved, thereby realizing the test of the stability of the workpiece under high-speed conditions.

[0039] A method for using an air suspension overspeed testing machine, characterized by the following steps:

[0040] 1) Install the test workpiece (15) to be tested on the test connection end (16) and tighten it with screws;

[0041] 2) High-pressure gas (0.4MPa, flow rate 5L / s) is continuously introduced through inlet A, inlet B1 and inlet B2;

[0042] 3) High-pressure gas (0.8MPa, flow rate 30L / s) is continuously introduced through the inlet C via a throttle valve;

[0043] 4) When the speed reaches the required level, the throttle valve makes corresponding adjustments, that is, the high pressure gas is kept stable by adjusting the control valve, so as to ensure that the speed of the rotor shaft (1) reaches the balance. When the test time requirement is reached, the air inlet C stops supplying gas. When the rotor shaft (1) stops rotating, the air inlet A, air inlet B1 and air inlet B2 stop supplying gas and the test workpiece (15) is disassembled.

[0044] During the testing process, the stability detection of the workpiece also requires a stability testing sensor. This sensor is a current traditional stability testing system, which is existing technology. Its structure and working principle will not be described in detail here. The inventive point of this technical solution is how to provide an air suspension testing machine that can provide high-speed rotation. The structure of this testing machine is the inventive innovation point of this technical solution. In the above embodiments, the best implementation of the present invention has been described. Obviously, under the inventive concept of the present invention, many changes can still be made. Here, it should be stated that any changes made under the inventive concept of the present invention will fall within the protection scope of the present invention.

Claims

1. An air suspension overspeed testing machine, characterized in that: The system includes a rotor shaft (1), which is fitted with a housing (2). An air guiding device is provided between the housing (2) and the rotor shaft (1) to allow the rotor shaft (1) to be suspended in mid-air. The air guiding device includes an air guiding cylinder (3) located outside the annular curved surface of the rotor shaft (1) and air distribution rings (4) located on two radial end faces of the rotor shaft (1). A first end cap (5) and a second end cap (6) are respectively provided at both ends of the housing (2). The first end cap (5) and the second end cap (6) fix the air guiding cylinder (3), the housing (2), and the air distribution rings (4) together. The rotor shaft (1) Installed in the chamber formed by the air guide cylinder (3) and the air distribution ring (4), there are gaps between the rotor shaft (1) and the air distribution ring (4) and the air guide cylinder (3); the air guide cylinder (3) is connected to the housing (2) by an air passage (7), the air passage (7) is an annular air passage (7), the air guide cylinder (3) is sleeved outside the rotor shaft (1), the air guide cylinder (3) is radially provided with several through holes (8) penetrating the inner and outer arms of the air guide cylinder (3), the through holes (8) are provided with plungers (9), the plungers (9) are provided with axially arranged capillary holes (10), the capillary holes (10) face the rotor shaft ( 1) The housing (2) is provided with an air inlet A that is connected to the air passage (7) between the air guide cylinder (3) and the housing (2); the first end cover (5) and the second end cover (6) are provided with air inlets B1 and B2 that are connected to the through holes (8) on the air distribution ring (4), and there are several air inlets B1 and B2 arranged in a ring; the air distribution ring (4) is provided with several through holes (8) that penetrate the two planes of the air distribution ring (4) in a ring, and a plunger (9) is provided in the through hole (8), and the plunger (9) is provided with capillary holes (10) arranged axially. The hole (10) is set perpendicular to the stepped end face of the rotor shaft (1); the side of the second end cover (6) is also provided with a vortex air guide plate (13), which is fixed on the second end cover (6) by screws. The rotor shaft (1) on one side of the second end cover (6) extends to the outside of the vortex air guide plate (13) and is connected to a turbine (14). The vortex air guide plate (13) is also provided with an air inlet C to provide power for the rotation of the turbine (14); the rotor shaft (1) on one side of the first end cover (5) extends outward to form a test connection end (16) for installing the test workpiece (15).

2. The air suspension overspeed testing machine according to claim 1, characterized in that: The rotor shaft (1) extends outward after passing through the first end cover (5) and the second end cover (6) at both ends. The rotor shaft (1) is a stepped shaft. The radial dimension of the rotor shaft (1) inside the air guide tube (3) is greater than the radial dimension extending to the outside of the end cover.

3. The air suspension overspeed testing machine according to claim 1, characterized in that: The valve ring (4) is fitted onto the stepped part of the rotor shaft (1), and the inner plane of the valve ring (4) is parallel to the stepped end face of the rotor shaft (1).

4. The air suspension overspeed testing machine according to claim 2, characterized in that: The first end cap (5) and the second end cap (6) are both provided with an inwardly recessed mounting groove (11) on the side near the air guide tube (3), and the air distribution ring (4) is installed in the mounting groove (11).

5. The air suspension overspeed testing machine according to claim 4, characterized in that: Both the first end cap (5) and the second end cap (6) have a positioning ring (12) protruding towards the air guide cylinder (3) on the side near the air guide cylinder (3).

6. A gas suspension overspeed testing machine according to any one of claims 1-5, characterized in that: The steps for using the air suspension overspeed test machine are as follows: 1) Install the test workpiece (15) to be tested at the test connection end (16) and tighten it with screws; 2) Continuously introduce 0.4MPa high-pressure gas with a flow rate of 5L / s through inlet A, inlet B1 and inlet B2. 3) 0.8MPa, flow rate 30L / s high pressure gas is continuously introduced through the throttle valve and inlet C; 4) When the speed reaches the requirement, the throttle valve makes corresponding adjustments, that is, the high pressure gas is kept stable by adjusting the control valve, so as to ensure that the speed of the rotor shaft (1) reaches balance. When the test time requirement is reached, the gas supply at inlet C stops. When the rotor shaft (1) stops rotating, the gas supply at inlet A, inlet B1 and inlet B2 stops, and the test workpiece (15) is disassembled.

Images