1. An apparatus for measuring the thickness of an oil film in a gear meshing area, the apparatus comprising:

the gear pair is composed of a driving wheel (4) and a driven wheel (6), and the gear pair is arranged in a gear box (9) with lubricating oil;

the motor (1) is used for driving the gear pair, and the motor (1) is connected to the driving wheel (4) through a driving shaft;

a brake (5) for providing a resisting torque, the brake (5) being connected to a driven wheel (6) through a driven shaft;

the oil film thickness measuring device comprises a driving wheel (4) and a driven wheel (6), wherein a modification area (62) lower than a gear meshing surface is arranged in a gear meshing area of the driving wheel (4) or the driven wheel (6), a mounting hole (63) is formed in the modification area (62), an eddy current sensor is mounted in the mounting hole (63), and when the driving wheel (4) is meshed with the driven wheel (6), the height difference between the driving wheel (4) and the driven wheel (6) before and after lubricating oil is introduced is measured through the eddy current sensor, so that the oil film thickness between the driving wheel (4) and the driven wheel (6) is obtained.

2. The device for measuring the thickness of the oil film in the gear meshing area is characterized in that the height of the modification area (62) lower than the gear meshing surface is determined according to the height of the eddy current sensor installed in the installation hole, and the height enables the driving wheel (4) and the driven wheel (6) not to interfere with the eddy current sensor in the meshing process when the eddy current sensor is installed in the installation hole.

3. Device for measuring the thickness of the oil film in the meshing area of a gear according to claim 1 or 2, characterised in that said profiled area (62) is located at the edge of the meshing area of the gear.

4. The device for measuring the oil film thickness of the gear meshing area according to claim 1 or 2, wherein a lead channel (64) communicated with the mounting hole (63) is arranged on the driving wheel (4) or the driven wheel (6) provided with the mounting hole (63), and the lead channel (64) is used for leading out a cable of the eddy current sensor.

5. The device for measuring the thickness of the oil film in the gear meshing area according to claim 4, wherein the wire passage (64) is arranged in the radial direction.

6. The device for measuring the thickness of the oil film in the gear meshing area is characterized by further comprising a torque and rotation speed sensor (7), wherein the torque and rotation speed sensor (7) is installed on the driving shaft and used for measuring the rotation speed.

7. Device for measuring the thickness of the oil film in the meshing area of gears according to claim 6, characterized in that it further comprises a coupling (2), said coupling (2) being used to connect the electric motor (1) to the driving shaft and/or to connect the driven shaft to the brake (5).

8. Device for measuring the thickness of the oil film in the meshing area of gears according to claim 7, characterised in that said brake (5) is a magnetic particle brake.

9. The device for measuring the thickness of the oil film in the gear meshing area is characterized by further comprising a measurement and control system, wherein the measurement and control system is connected with the motor (1), the brake (5), the eddy current sensor and the torque rotating speed sensor (7) and used for controlling the rotating speed and the loading torque of the gear pair and collecting and processing signals of the eddy current sensor and the torque rotating speed sensor.

10. A measuring method using the device for measuring the thickness of an oil film in a gear meshing area according to any one of claims 1 to 9, comprising:

a gear pair formed by a driving wheel (4) and a driven wheel (6) is driven by a motor (1);

lubricating oil is supplied to the meshing area of the gear pair through a gear box (9), so that an oil film is formed in the meshing area of the gear pair;

and measuring an eddy current sensor placed in any mounting hole of the driving wheel or the driven wheel, wherein the eddy current sensor is used for measuring the distance difference between the tooth surfaces before and after lubricating oil is introduced, and the oil film thickness of the gear is obtained.

Background

The gear system is an important power and transmission component of an aircraft engine, and the lubricating performance of the gear system greatly influences the service performance and the working efficiency of the gear system. The thickness of the oil film of the gear is an important parameter for evaluating the lubrication effect of the gear.

At present, methods commonly used for oil film thickness include a resistance method, a discharge voltage method, a displacement method, a capacitance method, an X-ray projection method, an optical interference method and the like, wherein the capacitance method and the optical interference method are the most effective. However, these methods are usually used for measuring the thickness of the oil film between the disks, and are mainly used for principle test verification, and are difficult to be applied to the measurement of the thickness of the oil film of the gear in actual working conditions. Because the rotation of the gear causes the lubricating oil and the air to form a two-phase flow field, the change of the measuring environment has great influence on the precision of the traditional measuring mode. Although the precision of measuring the oil film thickness by an optical method is high, the design of an optical path is very difficult, a measuring device is required to adopt a transparent material, and a plurality of limiting factors exist. Meanwhile, the gear meshing surface can be subjected to larger extrusion stress in actual working conditions, and if the oil film thickness is measured by directly burying a sensor in a gear meshing area, the bearing capacity of the gear becomes the technical bottleneck of a test scheme.

Therefore, a method or a device for measuring the thickness of the oil film in the gear meshing area is needed to solve the measurement problem.

Disclosure of Invention

It is an object of the present application to provide a device for measuring the thickness of an oil film in a gear meshing area to solve or mitigate at least one of the problems of the background art.

On one hand, the technical scheme provided by the application is as follows: an apparatus for measuring the thickness of an oil film in a gear meshing area, the apparatus comprising:

the gear pair is formed by the driving wheel and the driven wheel and is arranged in the gear box with lubricating oil;

the motor is used for driving the gear pair and is connected to the driving wheel through a driving shaft;

a brake for providing a resisting torque, the brake being connected to the driven wheel through the driven shaft;

the oil film thickness measuring device comprises a driving wheel, a driven wheel and a correcting area, wherein the gear meshing area of either the driving wheel or the driven wheel is provided with the correcting area lower than a gear meshing surface, the correcting area is internally provided with a mounting hole, an eddy current sensor is mounted in the mounting hole, and when the driving wheel is meshed with the driven wheel, the height difference between the driving wheel and the driven wheel before and after lubricating oil is introduced is measured through the eddy current sensor, so that the oil film thickness between the driving wheel and the driven wheel is obtained.

In a preferred embodiment of the present application, a height of the modified area below the gear meshing surface is determined according to a height of the eddy current sensor mounted in the mounting hole, and the height is such that when the eddy current sensor is mounted in the mounting hole, the driving wheel and the driven wheel do not interfere with the eddy current sensor during meshing.

In a preferred embodiment of the present application, the modification area is located at an edge of the gear meshing area.

In a preferred embodiment of the present application, a lead channel communicating with the mounting hole is provided on the driving wheel or the driven wheel having the mounting hole, and the lead channel is used for leading out a cable of the eddy current sensor.

In a preferred embodiment of the present application, the wire passage is arranged in a radial direction.

In a preferred embodiment of the present application, the apparatus further comprises a torque and rotation speed sensor mounted on the driving shaft for measuring a rotation speed.

In a preferred embodiment of the present application, the device further comprises a coupling for connecting the motor to the driving shaft and/or for connecting the driven shaft to the brake.

In a preferred embodiment of the present application, the brake is a magnetic particle brake.

In a preferred embodiment of the present application, the device further includes a measurement and control system, the measurement and control system is connected with the motor, the brake, the eddy current sensor and the torque speed sensor, and is used for controlling the rotating speed and the loading torque of the gear pair, and collecting and processing signals of the eddy current sensor and the torque speed sensor.

On the other hand, the technical scheme provided by the application is as follows: a measuring method using the device for measuring the oil film thickness in the gear meshing area, which comprises the following steps:

a gear pair formed by a driving wheel and a driven wheel driven by a motor;

lubricating oil is supplied to the meshing area of the gear pair through a gearbox, so that an oil film is formed in the meshing area of the gear pair;

and measuring an eddy current sensor placed in any mounting hole of the driving wheel or the driven wheel, wherein the eddy current sensor is used for measuring the distance difference between the tooth surfaces before and after lubricating oil is introduced, and the oil film thickness of the gear is obtained.

The measuring device that this application provided has advantages such as simple structure, with low costs, easily promote under can carrying out accurate measurement to oil film thickness.

Drawings

In order to more clearly illustrate the technical solutions provided by the present application, the following briefly introduces the accompanying drawings. It is to be expressly understood that the drawings described below are only illustrative of some embodiments of the invention.

FIG. 1 is a schematic diagram of the device for measuring the thickness of an oil film in a gear meshing area.

FIG. 2 is a schematic view of a modification zone on a driven wheel according to an embodiment of the present application.

Reference numerals:

1-electric machine

2-shaft coupling

3-bearing

4-driving wheel

5-brake

6-driven wheel

7-torque rotational speed sensor

8-electric slip ring

9-Gear case

61-Gear teeth

62-modification area

63-mounting hole

64-lead channel

Detailed Description

In order to make the implementation objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application.

In order to overcome the following defects of the prior art for measuring the thickness of an oil film:

1) the optical interference method for measuring the oil film thickness has the advantages that on one hand, the light path design is difficult, on the other hand, the test must be carried out by adopting a transparent material, the mechanical property of the transparent material is far different from that of a metal material, the load and the speed of the measuring working condition are limited, and the method is difficult to be used for measuring actual mechanical parts;

2) the thickness of an oil film is measured by a capacitance method, the thickness and physical property change of lubricating oil have adverse effect on the test process, and the test result is greatly influenced by the measurement environment;

3) the method for directly burying the sensor in the gear meshing area to measure the thickness of an oil film damages gear teeth, the bearing capacity of the gear is rapidly reduced, the crushing failure of the gear is easily caused during the measurement of the actual working condition, and the sensor is damaged and the measurement is interrupted.

The application provides a device and a method for online measurement of the thickness of a gear oil film by adopting an eddy current method.

As shown in fig. 1, the device for measuring the thickness of the oil film in the gear meshing area proposed by the present application mainly comprises: the motor 1, the driving wheel 4, the brake 5, the driven wheel 6 and the like, wherein the driving wheel 4 and the driven wheel 6 form a gear pair, the gear pair is arranged in a gear box 9, and the gear box 9 is connected with a lubricating oil supply system (not shown) capable of supplying lubricating oil. The motor 1 and a driving shaft supported by a bearing 3 are connected to a driving wheel 4 for driving the gear pair. The brake 5 is connected to the driven wheel 6 with a driven shaft supported by the bearing 3 for providing a resisting torque. Wherein, a modification area 62 lower than the gear meshing surface is arranged on the gear meshing area of either the driving wheel 4 or the driven wheel 6, a mounting hole 63 is arranged in the modification area 62 in the direction approximately vertical to the meshing surface, and an eddy current sensor (not shown) is mounted in the mounting hole 63. When the driving wheel 4 is meshed with the driven wheel 6 in the meshing area, the eddy current sensor measures the distance difference between the driving wheel 4 and the driven wheel 6 before and after the lubricating oil is introduced, and the oil film thickness of the gear meshing area is obtained.

The device that this application provided is under the prerequisite of guaranteeing oil film thickness measurement accuracy, can not receive the restriction of measuring the operating mode, also not influenced by lubricating oil rerum natura change etc. and the measurement principle is simple, the precision is high, and the interference killing feature is strong.

In a preferred embodiment of the present application, the height of the modified area 62 below the meshing surface of the gear is determined according to the height of the eddy current sensor installed in the installation hole, and the height is such that when the eddy current sensor is installed in the installation hole 63, the driving wheel 4 and the driven wheel 6 do not interfere with the eddy current sensor during meshing.

As shown in fig. 2, in the embodiment of the present application, a modified area 62 is provided on the driven wheel 6, and the modified area 62 is preferably provided at the edge of the gear teeth 61 of the driven wheel 6, so that the driven wheel 6 is engaged with the driving wheel 4 with as little load as possible, and the risk of damage to the eddy current sensor is avoided.

In a further preferred form of the above embodiment, a lead passage 64 is formed in the body of the driven wheel 6, and the lead passage 64 communicates with the mounting hole 63, which can be used as a passage for laying an eddy current sensor cable. Preferably, the lead passage 64 is arranged along the radial direction of the driven wheel 6, and after the lead of the eddy current sensor passes through the lead passage 64, the lead is laid along the driven shaft and passes through the gear box 9, and finally is connected to the electric slip ring 8 arranged at the end part of the driven shaft to realize data transmission.

In addition, in this application, the device may further include a torque and rotation speed sensor 7, where the torque and rotation speed sensor 7 is disposed on the driving shaft and is used for measuring the torque output by the motor 1 and the rotation speed of the driving wheel 4.

The device in the present application is used for measuring gear parts in an aircraft engine, so the gear structure and the like are generally large, and in order to realize torque transmission, the present application adopts the coupling 2 to connect the multiple motors 1 with the driving shaft, and simultaneously, the brake 5 is connected with the driven shaft through the coupling 2.

In the present application, the brake 5 is a magnetic powder brake. It will be appreciated that other types of brakes, such as electromagnetic brakes, may be used for the brake 5.

The device of the application further comprises a measurement and control system (not shown), wherein the measurement and control system is connected with the motor 1, the brake 5, the eddy current sensor and the torque rotating speed sensor 7 and used for controlling the rotating speed and the loading torque of the gear pair and collecting and processing signals of the eddy current sensor and the torque rotating speed sensor.

The device for measuring the thickness of the oil film in the gear meshing area has the following measuring process:

firstly, processing a modification area on the edge of a meshing area of one of a driving wheel and a driven wheel through a material removing process, and installing an eddy current sensor in the modification area;

installing a driving wheel and a driven wheel into a gear box, and leading out a lead of the eddy current sensor from the gear box;

the motor drives the driving wheel and the driven wheel to move, and meanwhile, lubricating oil is provided for the gear box through a lubricating oil system;

and measuring the distance difference between the tooth surfaces before and after the lubricating oil is introduced through the eddy current sensor to obtain the oil film thickness between the gears.

The device and the method for measuring the oil film thickness of the gear meshing area can realize online accurate measurement of the oil film thickness of the meshing area of the rotating metal gear component, only the gear is subjected to modification in measurement, the bearing capacity of the meshing area is not affected, the measuring working condition is not limited by load, rotating speed and the like, a measuring sensor has no damage risk, and the testing process principle is simple and is less affected by the environment.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.