Precise high-speed gas static pressure shaft system for friction torque measurement
By designing a precision high-speed gas static pressure shaft system for measuring friction torque, and employing an exhaust regulating valve and a combined throttle, the problem of low accuracy of the friction torque measuring instrument at high speeds was solved, achieving high-precision and stable friction torque measurement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-24
- Publication Date
- 2026-03-06
AI Technical Summary
Existing friction torque measuring instruments cannot meet the requirements of large load capacity, small friction torque with small fluctuations, and low moment of inertia at high speeds, resulting in low measurement accuracy.
A precision high-speed gas static pressure shaft system for measuring friction torque is designed. It adopts an exhaust regulating valve and a combined throttle to reduce friction torque fluctuations by adjusting the gas film pressure and gas outflow, thereby reducing the difficulty of preparing porous materials. The hollow design of the main shaft also reduces the moment of inertia.
This improved the measurement accuracy and stability of the friction torque measuring instrument at high speeds, and reduced friction torque fluctuations and rotational inertia.
Smart Images
Figure CN223976766U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of precision bearing measurement technology, specifically a precision high-speed gas static pressure shaft system for measuring friction torque. Background Technology
[0002] The frictional torque of a bearing is a key indicator for evaluating the quality of finished bearings, and it is generally tested under low-speed operation. With the rapid development of aerospace, high-precision machine tools and other fields, there is an increasing demand for evaluating the stability and energy loss of bearings at high speeds. Therefore, dynamic frictional torque testing of bearings under actual operating conditions is of great significance.
[0003] Currently, most friction torque measuring instruments produced domestically are used under special measurement conditions (measurement speed: 0.5~10r / min), and a few models can reach speeds of 300r / min. It is difficult to meet the conventional measurement conditions specified in GB / T32562-2016 (measurement speed = 0.5 × bearing limit speed). One of the main factors restricting the development of high-speed friction torque measuring instruments is the lack of high-precision measurement shaft systems.
[0004] Existing friction torque measuring instruments mostly employ orifice throttling, slit throttling, and porous material throttling systems. Among these, orifice and slit throttling systems suffer from varying degrees of problems, including low load capacity, large friction torque fluctuations at high speeds, and large moments of inertia. Compared to other types of throttling devices, porous material throttling systems offer better static and dynamic performance and are increasingly used. However, once the porous material is prepared and processed, its permeability is largely determined. In practical applications, micro-vibrations often occur after loading, causing large fluctuations in friction torque and introducing significant additional errors into the measurement system, severely affecting the instrument's measurement accuracy.
[0005] To solve the above problems, the measurement shaft structure of the existing testing instrument needs to be modified so that it can meet the requirements of large load capacity, small and fluctuating friction torque, and low moment of inertia within the speed range while maintaining high speed. Utility Model Content
[0006] The purpose of this invention is to propose a precision high-speed gas static pressure shaft system for measuring friction torque. By designing an exhaust regulating valve and a combined throttle, the friction torque fluctuation and rotational inertia of the shaft system are reduced, the preparation difficulty of porous materials is reduced, and the high-speed performance of the gas static pressure shaft system is improved.
[0007] The technical solution adopted by this utility model is: a precision high-speed gas static pressure shaft system for measuring friction torque, including a main shaft and a bearing seat coaxially sleeved on the outside of the main shaft, wherein the main shaft has two shoulders and a bearing outer peripheral surface disposed between the two shoulders;
[0008] An annular radial static pressure air chamber is formed between the bearing seat and the bearing outer peripheral surface, and an integral porous throttling device coaxial with the bearing seat is provided in the radial static pressure air chamber.
[0009] The bearing seat is provided with an axial static pressure air chamber facing the end face of the bearing shoulder, and a local porous throttle is provided in the axial static pressure air chamber;
[0010] The bearing seat is provided with an air inlet and an air passage system that connects the air inlet to the radial static pressure chamber and the axial static pressure chamber respectively.
[0011] The outer circular surface of the bearing seat is provided with an exhaust port that connects to the radial static pressure air chamber. An exhaust regulating valve core is provided in the exhaust port to adjust the osmotic pressure of the integral porous throttling device and the local porous throttling device.
[0012] As a preferred embodiment, the bearing seat includes a bushing and a lower thrust plate and an upper thrust plate disposed at both axial ends of the bushing, wherein the inner circular ends of the lower thrust plate and the upper thrust plate extend to form a thrust surface covering the end face of the shoulder.
[0013] As a preferred embodiment, the air passage system includes an axially connected air passage and a radial air intake passage disposed within the bushing, as well as an axial air intake passage disposed within the lower thrust plate and the upper thrust plate.
[0014] The radial air intake channel outlet end faces the outer peripheral surface of the bearing;
[0015] The air inlet end of the axially connected air passage is connected to the air inlet hole, and the air outlet end is connected to the radial air inlet passage and the axial air inlet passage, respectively.
[0016] As a preferred embodiment, the outer circular surface of the integral porous throttle is provided with an annular flow divider groove, the axial position of which corresponds to the outlet end of the radial air intake channel.
[0017] As a preferred embodiment, the outer circular surface of the integral porous throttling device is also provided with an annular pressure relief groove, which is connected to the exhaust port.
[0018] As a preferred embodiment, the diversion channel is provided in two parts and is symmetrically distributed along the axial direction, and the pressure relief channel is located at the axial midpoint between the two diversion channels.
[0019] As a preferred embodiment, the vent hole includes a cylindrical threaded cavity and a conical contraction cavity connected in sequence;
[0020] The exhaust regulating valve core includes a fine-tuning screw that mates with a cylindrical threaded cavity. The circumferential surface of the fine-tuning screw is provided with an axially penetrating exhaust groove, and the end of the fine-tuning screw is provided with an elastic sealing washer that mates with the conical surface of the conical contraction cavity.
[0021] As a preferred embodiment, there are two exhaust ports, which are distributed at an equal angle of 120° to the intake port in the circumferential direction of the bearing seat.
[0022] As a preferred embodiment, at least three localized multi-hole throttles are arranged at equal angles in the circumferential direction of the lower thrust plate and the upper thrust plate, respectively.
[0023] As a preferred embodiment, the outer circumferential surface of the bearing is fixedly provided with a lug for installation.
[0024] Compared with the prior art, the beneficial effects of this utility model are:
[0025] 1. This utility model, by designing an exhaust regulating valve, can control the gas outflow of the shaft system, adjust the gas film pressure, reduce frictional torque fluctuations, and reduce the difficulty of preparing porous materials.
[0026] 2. This utility model, through the integrated design of the exhaust regulating valve core and the bushing, makes the shaft system structure more compact and the adjustment more convenient.
[0027] 3. This utility model reduces the mass and rotation radius of the main shaft by fixing the thrust plate to the bushing and designing the hollow main shaft, thereby effectively reducing the rotational inertia of the shaft system. Attached Figure Description
[0028] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 This is a schematic diagram of the shaft system assembly of this utility model;
[0030] Figure 2 This is a schematic diagram of the shaft system cross-section of this utility model;
[0031] Figure 3 This is a schematic diagram of the main shaft of this utility model;
[0032] Figure 4 This is a schematic diagram of the cross-section of the shaft system of this utility model;
[0033] Figure 5 This is a schematic diagram of the exhaust regulating valve core of this utility model;
[0034] Figure 6 This is a schematic diagram of the assembly of the exhaust regulating valve core and the exhaust port in this utility model.
[0035] Figure label:
[0036] 1. Bushing; 101. Axial connecting air passage; 102. Radial air intake passage; 103. Axial air intake passage;
[0037] 2. Integral porous flow throttle, 201. Flow divider, 202. Pressure relief groove;
[0038] 3. Spindle, 301. Shoulder, 302. Bearing outer circumferential surface;
[0039] 4. Lower thrust plate;
[0040] 5. Upper thrust plate;
[0041] 6. Localized multi-hole throttling device;
[0042] 7. Exhaust regulating valve core; 701. Fine adjustment screw; 702. Elastic sealing washer; 703. Exhaust groove;
[0043] 8. Ear base;
[0044] 9. Vent hole; 901. Columnar threaded cavity; 902. Conical contraction cavity;
[0045] 10. Air intake. Detailed Implementation
[0046] The present invention will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.
[0047] It should be noted that, unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "a," "an," or "the," etc., used in this utility model patent application specification and claims do not express a quantity limitation, but rather indicate the presence of at least one; the terms "first," "second," and "third," as used herein, should not be considered as a limitation on the order of components, but are merely for distinguishing different components; the terms "comprising" or "including," etc., indicate that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including" and their equivalents, but do not exclude other elements or objects having the same function.
[0048] To more clearly describe the specific structural composition of this precision high-speed gas hydrostatic shaft system for measuring friction torque, see attached... Figure 1-6 This embodiment is described as follows:
[0049] like Figure 1-4As shown, a precision high-speed gas static pressure shaft system for measuring friction torque includes a main shaft 3 and a bearing seat coaxially sleeved on the outside of the main shaft 3. The main shaft 3 has two shoulders 301 and a bearing outer peripheral surface 302 disposed between the two shoulders 301. An annular radial static pressure chamber is formed between the bearing seat and the bearing outer peripheral surface 302. An integral porous throttling device 2 coaxial with the bearing seat is disposed in the radial static pressure chamber. An axial static pressure chamber (which can be cylindrical) is disposed in the bearing seat facing the end face of the shoulder 301. A local porous throttling device 6 is disposed in the axial static pressure chamber. The bearing seat has an air inlet 10 and an air passage system that connects the air inlet 10 to the radial static pressure chamber and the axial static pressure chamber respectively. An exhaust port 9 communicating with the radial static pressure chamber is disposed on the outer circular surface of the bearing seat. An exhaust regulating valve core 7 that can adjust the permeation pressure of the integral porous throttling device 2 and the local porous throttling device 6 is disposed in the exhaust port 9.
[0050] In the above embodiment, the bearing seat includes a bushing 1 and a lower thrust plate 4 and an upper thrust plate 5 disposed at both axial ends of the bushing 1. The inner circular ends of the lower thrust plate 4 and the upper thrust plate 5 extend to form a thrust surface covering the end face of the shoulder 301. A local porous throttle 6 is located on the thrust surface, and an air film is formed between the thrust surface and the end face of the shoulder 301.
[0051] In the above embodiment, an annular flow divider 201 and an annular pressure relief groove 202 are provided on the outer circular surface of the integral porous flow divider 2. The axial position of the flow divider 201 corresponds to the outlet end of the radial intake channel 102. The pressure relief groove 202 is connected to the exhaust port 9. Furthermore, there are two flow dividers 201 and they are symmetrically distributed along the axial direction. The pressure relief groove 202 is located at the axial middle position between the two flow dividers 201.
[0052] In the above embodiments, the air passage system specifically includes an axially connected air passage 101 and a radial air intake passage 102 disposed in the bushing 1, and an axial air intake passage 103 disposed in the lower thrust plate 4 and the upper thrust plate 5; the outlet end of the radial air intake passage 102 faces the outer peripheral surface 302 of the bearing; the air intake end of the axially connected air passage 101 is connected to the air intake hole 10, and the air outlet end is connected to the radial air intake passage 102 and the axial air intake passage 103 respectively.
[0053] The shaft system forms a gas static radial bearing and an axial gas static thrust bearing, and the external quick-connect plug is installed in the air inlet 10 to supply compressed air to the main shaft 3.
[0054] The integral porous throttle 2 and the outer diameter of the main shaft 3 form a gas static pressure radial bearing. The integral porous throttle 2 is glued to the inner hole of the bushing 1. Compressed air enters the diversion groove 201 of the integral porous throttle 2 through the axial connecting air passage 101, the radial air inlet passage 102, and the radial static pressure air chamber to provide radial support for the main shaft 3, thereby achieving radial load-bearing and high-precision rotary motion.
[0055] Multiple local porous throttling devices 6 are evenly distributed on the lower thrust plate 4 and the upper thrust plate 5 in the circumferential direction. The lower thrust plate 4 and the upper thrust plate 5 are installed on both ends of the bushing 1 by screws, and cooperate with the two shoulders 301 of the main shaft 3 to form a gas static pressure thrust bearing. Compressed air enters the local small-hole throttling device 6 through the axial connection channel 101, the axial air intake channel 103 and the axial static pressure air chamber, providing axial support for the shoulders 301 of the main shaft 3 and bearing the axial load. In order to ensure uniform airflow, at least three local porous throttling devices 6 are arranged at equal angles in the circumferential direction of the lower thrust plate 4 and the upper thrust plate 5.
[0056] During exhaust, the airflow passes through the pressure relief groove 202 of the integral porous throttling device 2 and enters the exhaust port 9;
[0057] See Figure 5 and Figure 6 Specifically, the exhaust port 9 includes a columnar threaded cavity 901 and a conical contraction cavity 902 connected in sequence; the exhaust regulating valve core 7 includes a fine-tuning screw 701 that cooperates with the columnar threaded cavity 901, the circumferential surface of the fine-tuning screw 701 is provided with an axially penetrating exhaust groove 703, and the end of the fine-tuning screw 701 is provided with an elastic sealing washer 702 that cooperates with the conical surface of the conical contraction cavity 902;
[0058] The exhaust regulating valve and the bushing are integrated into a single design. During commissioning, the gas discharge volume in the pressure relief groove 202 can be controlled and the gas film pressure adjusted by adjusting the gap between the sealing gasket 702 and the conical surface of the conical contraction chamber 902 by adjusting the screw length of the fine-tuning screw 702 according to the existing permeability, load and speed requirements of the porous throttling device. This achieves the purpose of reducing micro-vibration and friction torque fluctuations and improving the high-speed stability of the shaft system.
[0059] For example, there are two exhaust holes 9, and the two exhaust holes 9 and the air inlet hole 10 are distributed at an equal angle of 120° in the circumferential direction of the bearing, which can ensure uniform pressure in the shaft system.
[0060] The spindle 3 is made of low-density, high-strength titanium alloy material, and its internal design is a multi-stage hollow structure, which reduces the weight of the spindle and thus achieves the purpose of low rotational inertia; the outer circumferential surface of the bearing seat is fixedly provided with a lug 8 for installation.
[0061] The parts not described in detail in the above embodiments are existing technologies.
[0062] It should be noted that although the present invention has been described through the above embodiments, there may be other various embodiments of the present invention. Without departing from the spirit and scope of the present invention, those skilled in the art can obviously make various corresponding changes and modifications to the present invention, but all such changes and modifications should fall within the scope of protection of the appended claims and their equivalents.
Claims
1. A precision high-speed aerostatic shafting for friction torque measurement, characterized in that: The shaft seat comprises a shaft sleeve (1) and a lower thrust plate (4) and an upper thrust plate (5) arranged at the axial two ends of the shaft sleeve (1), and the inner circular face end of the lower thrust plate (4) and the upper thrust plate (5) extends to form a thrust face covering the end face of the shaft shoulder (301). The shaft seat and the bearing outer circumferential surface (302) form an annular radial static pressure gas cavity, and a whole-type porous restrictor (2) coaxial with the shaft seat is arranged in the radial static pressure gas cavity. An axial static pressure gas cavity is arranged in the shaft seat and faces the end face of the shaft shoulder (301), and a local porous restrictor (6) is arranged in the axial static pressure gas cavity. The shaft seat is provided with an air inlet hole (10) and an air channel system for respectively connecting the air inlet hole (10) with the radial static pressure gas cavity and the axial static pressure gas cavity. An exhaust hole (9) is arranged on the outer circumferential surface of the shaft seat and communicates with the radial static pressure gas cavity, and an exhaust adjusting valve core (7) is arranged in the exhaust hole (9) and is used for adjusting the permeation pressure of the whole-type porous restrictor (2) and the local porous restrictor (6).
2. The precise high-speed aerostatic shafting for friction torque measurement according to claim 1, characterized in that: The shaft seat comprises a shaft sleeve (1) and a lower thrust plate (4) and an upper thrust plate (5) arranged at the axial two ends of the shaft sleeve (1), and the inner circular face end of the lower thrust plate (4) and the upper thrust plate (5) extends to form a thrust face covering the end face of the shaft shoulder (301).
3. The precise high-speed aerostatic shafting for friction torque measurement according to claim 2, characterized in that: The air channel system comprises an axial connection air channel (101) and a radial air inlet channel (102) arranged in the shaft sleeve (1), and an axial air inlet channel (103) arranged in the lower thrust plate (4) and the upper thrust plate (5); The outlet end of the radial air inlet channel (102) faces the bearing outer circumferential surface (302); The air inlet end of the axial connection air channel (101) is connected with the air inlet hole (10), and the air outlet end is respectively connected with the radial air inlet channel (102) and the axial air inlet channel (103).
4. The precise high-speed aerostatic shafting for friction torque measurement according to claim 3, characterized in that: The outer circumferential surface of the whole-type porous restrictor (2) is provided with an annular shunt groove (201), and the axial position of the shunt groove (201) corresponds to the outlet end of the radial air inlet channel (102).
5. The precise high-speed aerostatic shafting for friction torque measurement according to claim 4, characterized in that: The outer circumferential surface of the whole-type porous restrictor (2) is further provided with an annular pressure relief groove (202), and the pressure relief groove (202) communicates with the exhaust hole (9).
6. The precise high-speed aerostatic shafting for friction torque measurement according to claim 5, characterized in that: The shunt groove (201) is provided with two and is symmetrically distributed along the axial direction, and the pressure relief groove (202) is located at the axial intermediate position between the two shunt grooves (201).
7. The precise high-speed aerostatic shafting for friction torque measurement according to claim 1, characterized in that: The exhaust hole (9) comprises a columnar threaded cavity (901) and a tapered contraction cavity (902) which are sequentially connected; The exhaust adjusting valve core (7) comprises a fine adjustment screw (701) matched with the columnar threaded cavity (901), the circumferential surface of the fine adjustment screw (701) is provided with an exhaust groove (703) penetrating in the axial direction, and the end of the fine adjustment screw (701) is provided with an elastic sealing washer (702) matched with the tapered surface of the tapered contraction cavity (902).
8. The precise high-speed aerostatic shafting for friction torque measurement according to claim 1, characterized in that: The exhaust hole (9) is provided with two, and the two exhaust holes (9) and the air inlet hole (10) are distributed at an angle of 120° in the circumferential direction of the shaft seat.
9. The precise high-speed aerostatic shafting for friction torque measurement according to claim 3, characterized in that: The local porous restrictor (6) is arranged at least three in the circumferential direction of the lower thrust plate (4) and the upper thrust plate (5) respectively.
10. The precise high-speed aerostatic shafting for friction torque measurement according to claim 1, characterized in that: The outer circumferential surface of the shaft seat is fixedly provided with an ear seat (8) for installation.