A method for testing bearing friction torque

Abstract

This invention relates to the field of bearing testing technology, specifically a method for testing bearing friction torque. The method involves mounting a test bearing on a rotating shaft, applying a first horizontal force Fr1 to the test bearing, starting a motor, and rotating the bearing at a speed n. A torque sensor is used to measure the first friction torque M1 of the current shaft system. Two auxiliary test bearings of the same specifications as the test bearing are mounted side-by-side on the rotating shafts on either side of the test bearing. A first horizontal force Fr1 is applied to the middle test bearing, while a second horizontal force Fr2, equal in magnitude but opposite in direction to the first horizontal force Fr1, is applied to each of the two auxiliary test bearings. The motor is started, and a torque sensor is used to measure the second friction torque M2 of the shaft system. The friction torque of the test bearing under the load of the first horizontal force Fr1 and at a speed n is calculated as (M2 - M1) / 2. This method effectively eliminates the friction torque of the rotor system's supporting bearings, accurately obtaining the friction torque result of the test bearing.

Description

Technical Field

[0001] This invention relates to the field of bearing testing technology, specifically a method for testing bearing friction torque. Background Technology

[0002] Bearing friction torque is a key performance indicator characterizing bearing operation. Low and stable friction torque means less bearing wear, which can extend equipment maintenance cycles and reduce downtime losses. The friction torque of rolling bearings is a key indicator of their rotational resistance, directly determining the energy consumption and temperature rise level of the mechanical system, and is a critical factor affecting the motion accuracy and reliability of equipment. Accurately obtaining bearing friction torque can guide precise equipment design, and monitoring changes in friction torque can also provide early warning of lubrication failure or identify early-stage faults.

[0003] Conventional methods for measuring frictional torque involve placing torque sensors at the motor output and shaft ends. However, the measured value is the frictional torque of the entire rotor system, which includes the frictional torque of the supporting bearing and the test bearing. Therefore, it is impossible to accurately obtain the frictional torque of the bearing under test. Summary of the Invention

[0004] In view of the deficiencies of the prior art, the present invention provides a bearing friction torque testing method, which realizes the acquisition of bearing body friction torque under various load, speed and other working conditions. This method can effectively eliminate the friction torque of the rotor system support bearing and accurately obtain the test bearing friction torque results.

[0005] To achieve the above objectives, the present invention provides a bearing friction torque testing method, employing a friction torque measuring device. The friction torque measuring device includes a motor, a rotating shaft connected to the output end of the motor, a torque sensor mounted on the rotating shaft, and a first support bearing and a second support bearing mounted on the rotating shaft. Specific steps include: Step S100: Install the test bearing on the shaft and between the first support bearing and the second support bearing. Apply a first horizontal force Fr1 to the test bearing. Start the motor. Measure the given running time through the torque sensor. After the test bearing reaches thermal equilibrium, measure the current bearing speed n and the first friction torque M1 of the current shaft system. Step S200: Install two auxiliary test bearings of the same specifications as the test bearing side by side on the rotating shafts on both sides of the test bearing. Apply a first horizontal force Fr1 to the middle test bearing, and simultaneously apply a second horizontal force Fr2 to the two auxiliary test bearings, which is equal in magnitude but opposite in direction to the first horizontal force Fr1. Start the motor, and measure the second friction torque M2 of the shaft system after the test bearing and the two auxiliary test bearings have reached thermal equilibrium under the same speed and time conditions as in step S100, using the torque sensor. Step S300: Calculate (M2-M1) / 2 to obtain the friction torque of the test bearing under the load of the first horizontal force Fr and the rotational speed n.

[0006] Furthermore, the friction torque measuring device includes a test platform, on which a first support bearing support and a second support bearing support are provided, the first support bearing being installed on the first support bearing support and the second support bearing being installed on the second support bearing support.

[0007] Furthermore, the friction torque measuring device includes a first hydraulic cylinder disposed on one side of the test bearing, the first hydraulic cylinder being used to apply a first horizontal force Fr1 to the test bearing.

[0008] Furthermore, the friction torque measuring device includes two auxiliary hydraulic cylinders respectively disposed on one side of the two auxiliary test bearings, the auxiliary hydraulic cylinders being used to apply a second horizontal force Fr2 to the auxiliary test bearings.

[0009] Furthermore, the friction torque measuring device includes a motor support, and the motor is mounted on the motor support.

[0010] Furthermore, the friction torque measuring device includes a baffle, which is disposed at the end of the rotating shaft away from the motor.

[0011] Furthermore, both the first and second support bearings are 6207 deep groove ball bearings, and the test bearing is a NU306EM cylindrical roller bearing.

[0012] The beneficial effects of this invention are: it solves the technical problem that existing bearing friction torque testing technologies cannot obtain the friction torque of a test bearing independently, and proposes a friction torque measurement method based on the principle of force balance, which uses the method of calculating the difference between two measurements to calculate the friction torque of a single tested bearing.

[0013] This invention utilizes a torque sensor to test the frictional torque of a shaft system and proposes a method to effectively extract the frictional torque of a test bearing from the frictional torque of the shaft system. This method achieves effective differentiation between the frictional torque of the test bearing and the support bearing by setting different numbers of test bearings in two separate steps and applying horizontal forces of the same magnitude but opposite directions, thus overcoming the problem of inaccurate measurement of the frictional torque of the bearing body itself. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of step S100 of a bearing friction torque testing method according to an embodiment of the present invention; Figure 2This is a schematic diagram of step S200 of a bearing friction torque testing method according to an embodiment of the present invention; In the picture: 10. Testing platform 100. Motor; 110. Motor support; 200. Shaft, 300. Torque sensor; 310. Torque sensor support. 410. First support bearing; 411. First support bearing support; 420. Second support bearing; 421. Second support bearing support. 510. Test bearing; 511. First hydraulic cylinder; 520. First auxiliary test bearing; 521. First auxiliary hydraulic cylinder; 530. Second auxiliary test bearing; 531. Second auxiliary hydraulic cylinder. 600, baffle. Detailed Implementation

[0015] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0016] A bearing friction torque testing method employs a friction torque measuring device, which includes a motor 100, a rotating shaft 200 connected to the output end of the motor 100, a torque sensor 300 mounted on the rotating shaft 200, and a first support bearing 410 and a second support bearing 420 mounted on the rotating shaft 200; both the first support bearing 410 and the second support bearing 420 are 6207 deep groove ball bearings.

[0017] The specific steps include: Step S100, see Figure 1The test bearing 510 is installed on the rotating shaft 200, between the first support bearing 410 and the second support bearing 420. The test bearing 510 is a NU306EM cylindrical roller bearing. A first horizontal force Fr1 = 20kN is applied to the test bearing 510. The first horizontal force Fr1 is applied tangentially to the outer ring of the test bearing 510. According to the principle of mechanics, the first support bearing 410 and the second support bearing 420 at both ends are subjected to forces in the opposite direction to the test bearing 510, with a magnitude of Fr1 / 2. The motor 100 is started, and the torque sensor 300 measures the given running time (3000s). After the test bearing 510 reaches thermal equilibrium, the current bearing speed n = 3000r / min, and the current first frictional torque M1 of the shaft system = 29.3Nm. M1 can be directly read from the torque sensor 300. At this time, the first frictional torque M1 of the shaft system includes the frictional torque of the test bearing 510, the first support bearing 410, and the second support bearing 420.

[0018] Step S200, see Figure 2 Two auxiliary test bearings of the same specifications as the test bearing 510, namely the first auxiliary test bearing 520 and the second auxiliary test bearing 530, are installed side by side on the rotating shafts 200 on both sides of the test bearing 510. That is, three NU306EM cylindrical roller bearings are installed side by side. A first horizontal force Fr1=20kN is applied to the middle test bearing 510. At the same time, a second horizontal force Fr2, which is equal in magnitude but opposite in direction to the first horizontal force Fr1, is applied to the first auxiliary test bearing 520 and the second auxiliary test bearing 530 respectively. The first horizontal force Fr1 is applied at a position tangent to the outer ring of the test bearing 510, and the second horizontal force Fr2 is applied at a position tangent to the outer rings of the first auxiliary test bearing 520 and the second auxiliary test bearing 530. According to the force relationship, the load on the first support bearing 410 and the second support bearing 420 is Fr1 / 2. When the motor 100 is started, and the torque sensor 300 measures the same speed and time conditions as in step S100, after the test bearing 510, the first auxiliary test bearing 520, and the second auxiliary test bearing 530 all reach thermal equilibrium, the second frictional torque M2 of the shaft system is 56.3 Nm. M2 can be directly read from the torque sensor 300. At this time, the second frictional torque M2 of the shaft system includes the frictional torque of five bearings: the test bearing 510, the first auxiliary test bearing 520, the second auxiliary test bearing 530, the first support bearing 410, and the second support bearing 420.

[0019] Step S300: Calculate (M2-M1) / 2 = 13.5 Nm, obtaining the frictional torque of test bearing 510 under a load of the first horizontal force Fr1 = 20 kN and a rotational speed n = 3000 r / min, which is 13.5 Nm. Subtracting the second frictional torque M2 measured in step S200 from the first frictional torque M1 measured in step S100, the frictional torques of the first auxiliary test bearing 520 and the second auxiliary test bearing 530 can be obtained. Since the first auxiliary test bearing 520 and the second auxiliary test bearing 530 are consistent with test bearing 510 in terms of model, environment, lubrication, etc., the frictional torque of test bearing 510 under a load of the first horizontal force Fr1 and a rotational speed n can be effectively obtained by calculating (M2-M1) / 2.

[0020] In one embodiment, the friction torque measuring device includes a test platform 10, on which a first support bearing support 411 and a second support bearing support 421 are provided. The first support bearing 410 is installed on the first support bearing support 411, and the second support bearing 420 is installed on the second support bearing support 421.

[0021] In one embodiment, the friction torque measuring device includes a first hydraulic cylinder 511 disposed on one side of the test bearing 510, the first hydraulic cylinder 511 being used to apply a first horizontal force Fr1 to the test bearing 510.

[0022] In one embodiment, the friction torque measuring device includes two auxiliary hydraulic cylinders respectively disposed on one side of two auxiliary test bearings, namely a first auxiliary hydraulic cylinder 521 and a second auxiliary hydraulic cylinder 531. The first auxiliary hydraulic cylinder 521 is used to apply a second horizontal force Fr2 to the first auxiliary test bearing 520, and the second auxiliary hydraulic cylinder 531 is used to apply a second horizontal force Fr2 to the second auxiliary test bearing 530.

[0023] In one embodiment, the friction torque measuring device includes a motor support 110, and a motor 100 is mounted on the motor support 110.

[0024] In one embodiment, the friction torque measuring device includes a baffle 600 disposed at the end of the rotating shaft 200 away from the motor 100. A graphite self-lubricating bushing is press-fitted at the connection between the baffle 600 and the rotating shaft 200, and the rotating shaft 200 rotates only within the bushing while the baffle 600 remains stationary.

[0025] The test platform 10 is equipped with a torque sensor support 310, and a torque sensor 300 is mounted on the torque sensor support 310.

[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0029] In this invention, unless otherwise explicitly specified and limited, "above" or "below" a second feature can mean that the first and second features are in direct contact, or that they are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of a second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" a second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature. It should be noted that when an element is referred to as "fixed to" or "set on" another element, it can be directly on the other element or there may be an intermediate element present. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element present. The terms "vertical," "horizontal," "above," "below," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible embodiments.

Claims

1. A method for testing bearing friction torque, employing a friction torque measuring device, the friction torque measuring device comprising a motor, a rotating shaft connected to the output end of the motor, a torque sensor disposed on the rotating shaft, and a first support bearing and a second support bearing mounted on the rotating shaft; Its features are, The specific steps include: Step S100: Install the test bearing on the shaft and between the first support bearing and the second support bearing. Apply a first horizontal force Fr1 to the test bearing. Start the motor. Measure the given running time through the torque sensor. After the test bearing reaches thermal equilibrium, measure the current bearing speed n and the first friction torque M1 of the current shaft system. Step S200: Install two auxiliary test bearings of the same specifications as the test bearing side by side on the rotating shafts on both sides of the test bearing. Apply a first horizontal force Fr1 to the middle test bearing, and simultaneously apply a second horizontal force Fr2 to the two auxiliary test bearings, which is equal in magnitude but opposite in direction to the first horizontal force Fr1. Start the motor, and measure the second friction torque M2 of the shaft system after the test bearing and the two auxiliary test bearings have reached thermal equilibrium under the same rotational speed and time conditions as in step S100, using the torque sensor. Step S300: Calculate (M2-M1) / 2 to obtain the friction torque of the test bearing under the load of the first horizontal force Fr1 and the rotational speed n.

2. The bearing friction torque testing method according to claim 1, characterized in that: The friction torque measuring device includes a test platform, on which a first support bearing support and a second support bearing support are provided. The first support bearing is installed on the first support bearing support, and the second support bearing is installed on the second support bearing support.

3. The bearing friction torque testing method according to claim 1, characterized in that: The friction torque measuring device includes a first hydraulic cylinder disposed on one side of the test bearing, the first hydraulic cylinder being used to apply a first horizontal force Fr1 to the test bearing.

4. The bearing friction torque testing method according to claim 1, characterized in that: The friction torque measuring device includes two auxiliary hydraulic cylinders respectively disposed on one side of the two auxiliary test bearings. The auxiliary hydraulic cylinders are used to apply a second horizontal force Fr2 to the auxiliary test bearings.

5. The bearing friction torque testing method according to claim 1, characterized in that: The friction torque measuring device includes a motor support, and the motor is mounted on the motor support.

6. The bearing friction torque testing method according to claim 1, characterized in that: The friction torque measuring device includes a baffle, which is disposed at the end of the rotating shaft away from the motor.

7. The bearing friction torque testing method according to claim 1, characterized in that: Both the first and second support bearings are 6207 deep groove ball bearings, and the test bearing is a NU306EM cylindrical roller bearing.

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