JP2000180277A - Rotational contact resistance measuring device and bearing rotational resistance measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotational contact resistance measuring device capable of measuring minute rotational contact resistance without receiving disturbance caused by bearing resistance torque that is fluctuated by a baring load, etc. SOLUTION: A testing machine 1 comprises a simulation wheel 31 as a first rotational body and a rail simulation wheel 55 as a second rotational body. Then while the wheel 31 is being pressed against the rail simulation wheel 55 by a pressure mechanism 9, each wheel is rotated by motors 3 and 63 to perform a rotational contact resistance measurement. Alternatively, the rotational resistance measurement of a bearing 28 is performed. A driving side torquemeter 35 is mounted on an axle 33 between an drive side bearing 27 and the wheel 31 and an anti-driving side torquemeter 27 is mounted on the axle 33 between an outboard bearing 28 and the wheel 31. By subtracting resistance torque of the bearing from driving toque or breaking torque of the rotational axis, adhesion power can be measured more accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary contact resistance measuring device for measuring the characteristics of adhesion of a railway wheel to a rail. In particular, the present invention relates to a rotational contact resistance measuring device capable of measuring a minute rotational contact resistance without being affected by disturbance caused by a resistance torque of a bearing that fluctuates due to a rotational speed, a bearing load, a bearing temperature, a thrust force, and the like. In addition, the present invention relates to a bearing rotation resistance measuring device capable of measuring a resistance torque of a bearing under various conditions.

[0002]

2. Description of the Related Art A description will be given of a test machine (hereinafter referred to as a wheel / rail test machine) for measuring the adhesive force characteristics of a railway wheel to a rail and rolling fatigue characteristics. The friction between the wheels and rails of a railway vehicle is an important factor related to the acceleration / deceleration performance of the vehicle. In the railway industry, the horizontal load acting on wheels is usually referred to as adhesion, and this value is the main subject of discussion.

A wheel / rail tester has a first rotating body as a simulated wheel and a second rotating body as a simulated rail. A rotation difference is provided by giving a speed difference (slip).
Then, the adhesive force between the two rotating bodies and the wear rate (mm / km) of the wheel and the rail are measured.

[0004]

SUMMARY OF THE INVENTION One of the methods for measuring adhesive strength
One method is to measure the driving (or braking) torque acting on the wheels and divide the torque by the radius of the wheels. However, strictly speaking, this driving torque includes the rotational resistance torque of the bearing that supports the wheel axle, which causes a measurement error.

As a method of canceling the bearing resistance torque as much as possible, the following method can be considered. Before applying the test load to the rotating body, after running the rotating body for a certain period of time and allowing the bearing temperature to rise to some extent (for example, 60 ° C)
Next, the idling torque of the rotating shaft is measured. Then, after starting the measurement by applying a load, the idle torque is added to and subtracted from the measured torque to calculate a torque corresponding to the adhesive force.

However, the idling torque merely represents the bearing resistance torque under a specific condition.
The actual bearing resistance torque varies depending on the load (radial, thrust, moment) applied to the bearing, the number of revolutions, the temperature, the state of wear of the bearing, and the like. Furthermore, in recent tests for ultra-high-speed railways (500 km / hr), the presence or absence of slight adhesive strength is a problem, unlike before,
A method should be established to more accurately cancel bearing resistance torque, which was previously thought to be negligible. It should be noted that attention to such a problem is first raised by the present inventors this time.

The present invention is based on the above-mentioned novel attention, and has as its object to provide the following rotational contact resistance measuring device or bearing rotational resistance measuring device. It can accurately measure the adhesive force characteristics of railway wheels to rails. A minute rotational contact resistance can be measured without being affected by disturbance caused by the resistance torque of the bearing which fluctuates according to the rotational speed, the bearing load, the bearing temperature, the thrust force and the like. The resistance torque of the bearing under various conditions can be measured.

[0008]

According to a first aspect of the present invention, there is provided a rotary contact resistance measuring apparatus comprising: a first rotating body; a bearing for supporting the first rotating body; A driving mechanism for rotating the rotating body at a first peripheral speed; a second rotating body; a bearing for supporting the second rotating body; and a driving mechanism for rotating the second rotating body at a second peripheral speed. A pressing mechanism for applying a pressing force between the outer circumference of the first rotating body and the outer circumference of the second rotating body; a load cell for measuring the pressing force; and a driving torque for measuring a driving torque of the first rotating body. And a resistance torque meter for measuring a resistance torque of a bearing that supports the first rotating body.

[0009] By subtracting the resistance torque of the bearing from the driving torque or braking torque of the rotating shaft, the torque based on the adhesive force, and hence the adhesive force, can be measured more accurately. The resistance torque of the bearing is accurate because it is an actually measured value at the time of the load and the number of rotations during the test.

A rotary contact resistance measuring device according to a second aspect of the present invention includes a lateral moving mechanism or a rotating mechanism for periodically moving the first rotator and the second rotator relatively in the direction of the rotation axis. .

In a general rotary contact resistance measuring device,
As the measurement is continued, a phenomenon that the rotational contact resistance (adhesive force of the wheel) gradually decreases may be observed. This is because the same outer peripheral surface of the rotating body repeats rotational contact,
It is thought that it gradually becomes "adapted". The phenomenon we want to simulate in the case of a wheel / rail tester is a phenomenon in which wheels roll on the surface of a long rail,
The rotation history phenomenon is an undesirable phenomenon that does not actually occur. For this reason, a rotating contact resistance measuring device that constantly repeats contact at the same location on the outer peripheral surface of the rotating body can only obtain a measured value lower than the actual adhesion between the wheel and the rail. This is a particularly serious problem in development and testing for ultra-high-speed railways.

Therefore, in the rotational contact resistance measuring device according to the second aspect of the present invention, the first rotating body and the second rotating body are relatively moved periodically in the direction of the rotation axis, and the same portion during the measurement is measured. To avoid repeated contact. Therefore, it is possible to measure the wheel adhesive force characteristic closer to the actual state.

The rotary contact resistance measuring device of the present invention preferably includes a twist mechanism for twisting the rotation axes of the first rotating body and the second rotating body. In addition, the first
It is preferable to include a contact angle imparting mechanism for mutually inclining the rotation axes of the rotating body and the second rotating body. This allows
The simulation of the contact state between the wheel and the rail when the railway vehicle travels on the curved section can be performed in a form closer to the actual state.

A bearing rotation resistance measuring device according to a first aspect of the present invention includes a shaft fitted to an inner ring of a bearing, a pressing mechanism for applying a radial load to an outer ring of the bearing, and a drive for rotating the shaft at an arbitrary speed. A mechanism, and a resistance torque meter for measuring a bearing resistance torque applied to a shaft between the bearing and the drive mechanism is provided.

According to the bearing rotational resistance measuring device, it is possible to measure the bearing resistance when the load state, the rotational speed, and the cumulative rotational speed of the bearing change. Therefore, a new performance evaluation criterion can be provided for a bearing in which only the standard values for the maximum load and the maximum number of revolutions have been conventionally known. In particular, in the case of railway wheel bearings, it is possible to grasp the amount of increase in the running resistance value depending on the occupancy rate for each train set, and thus very important data can be obtained in terms of the operation and design of the vehicle.

It is preferable that the bearing rotational resistance measuring device of the present invention further includes a mechanism for applying a thrust load to the bearing. A change in bearing rotation resistance due to a thrust load can also be simulated. A means for applying a thrust load is preferably a hydraulic cylinder or the like.

A bearing rotational resistance measuring device according to a second aspect of the present invention comprises: a first rotating body; a bearing supporting the first rotating body; and a drive for rotating the first rotating body at a first peripheral speed. A mechanism, a second rotating body, a bearing for supporting the second rotating body, a driving mechanism for rotating the second rotating body at a second peripheral speed, an outer periphery of the first rotating body, and a second rotation A pressing mechanism for applying a pressing force to the outer periphery of the body, a load cell for measuring the pressing force, and a resistance torque meter for measuring a resistance torque of a bearing supporting the first rotating body. And

The bearing rotational resistance measuring device according to the second aspect can measure the bearing resistance of a railway wheel bearing or the like in a more realistic manner. It is preferable that the bearing rotation resistance measuring device of this aspect includes a twist mechanism for twisting the rotation axes of the first rotating body and the second rotating body. In addition, it is preferable to include a contact angle imparting mechanism that inclines the rotation axes of the first rotating body and the second rotating body with respect to each other. This makes it possible to simulate the state of contact between the wheels and the rail when the railway vehicle travels on the curved section in a manner closer to the actual state.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically showing a configuration of a wheel / rail tester according to one embodiment of the present invention. FIG. 2 is a block diagram showing a configuration of a measurement control system of the wheel / rail tester of FIG. This tester 1 includes a simulation wheel 31 as a first rotating body and a rail simulation wheel 55 as a second rotating body. Then, while the wheel 31 is pressed against the simulated rail wheel 55 by the pressing mechanism 9, each wheel is rotated by the motors 3 and 63 to measure the rotational contact resistance. Alternatively, the bearing 28
Measurement of rotational resistance.

An axle 33 is fitted and fixed to the wheel 31. The axle 33 is rotatably supported by two bearings (a driving bearing 27 and a non-driving bearing 28) on both sides of the wheel 31. The non-drive side bearing 28 has a thermometer 2
9 is attached.

An axle 33 between the drive-side bearing 27 and the wheel 31
, A drive-side torque meter 35 is mounted, and an anti-drive-side torque meter 37 is mounted on the axle 33 between the non-drive-side bearing 28 and the wheel 31. These torque meters 3
Reference numerals 5 and 37 denote known non-contact torque meters attached to the axle. Although not shown, each torque meter includes a strain gauge, a circuit for detecting the strain thereof, an FM telemeter for wirelessly transmitting an output, and the like. Note that the strain gauge is attached to a position 180 ° opposite to the axle 33, and the bending strain applied to the axle 33 is canceled.

The axle 33 is driven to rotate by the DC motor 3 on the left side of the figure via the connecting shaft 5 and the constant velocity joint 7. The DC motor 3 has a built-in encoder and drives the axle 33 at an arbitrary rotation speed. An encoder 41 and a slip ring 43 are provided on the right side of the axle 33, and detect the rotation speed of the axle 33, the bearing temperature, and the like.

The simulated rail wheel 55 is rotatably supported by bearings 51 and 57 via a shaft 53 fitted and fixed to the wheel, and is driven at an arbitrary rotational speed by a DC motor 63.

The pressing mechanism 9 includes a hydraulic pressing cylinder 11
Is provided. The cylinder 11 drives a vertically moving frame 15 of the pressing mechanism in a vertical direction. The frame 15 is guided by the upward linear guide 13 at both ends. Below the vertically moving frame 15, a left and right moving frame 19 is held via a left and right linear guide 17 so as to be able to move left and right. At the left end of the vertical moving frame 15, a horizontal moving cylinder 21 is controlled. Left and right moving frame 1
9 is driven by the same cylinder 21 to the left and right in the figure.

A load cell 23 is provided below the left and right moving frame 19. Actually, four load cells 23 are arranged, one at each of the four corners of the frame 19. Under the load cell 23, a bearing frame 25 is attached. The bearing frame 25 hangs left and right, and bearings 27 and 28 are attached to its lower end.

Next, the operation of the wheel / rail tester of FIG. 1 will be described. The pressing force of the pressing cylinder 11 acts on the wheels 31 via the frames 15, 19, 25, bearings 27, 28, and axle 33, and presses the wheels 31 against the simulated rail wheels 55. The pressing force can be detected by the load cell 23. By moving the laterally moving cylinder 21, the wheels 31
Are driven left and right. Accordingly, the rolling can be performed while always considering the contact position between the wheel 31 and the simulated rail wheel 55, and as described above, the adhesion characteristic test between the wheel and the rail can be performed in a manner closer to the actual state. Or,
If the wheel 31 or the simulated rail wheel 55 is provided with a flange, the lateral movement cylinder 21 can apply a thrust load to the shaft 31 and the bearings 27 and 28.

The pressing mechanism 9 and the wheels 31 can be slightly rotated in a horizontal plane by a manual adjustment mechanism (not shown). By adjusting this mechanism, an attack angle between the wheel 31 and the simulated rail wheel 55 can be provided. Note that the attack angle is, as shown in FIG.
And 55 are the twist angles α of the rotating shafts, and are the angles formed by the peripheral velocity vectors of both wheels. This makes it possible to simulate the behavior of wheels and rails on a curved track.

Further, a contact angle β (FIG. 1) can be given between the wheel 31 and the simulated rail wheel 55. This angle provides an opening between the rotating shafts 33 and 53 of both wheels. Specifically, the rail simulation wheel 55 and the drive motor 6
3 is placed on the entire bed 65 on which the actuator 6 is mounted.
Tilt at 7.

By adjusting the rotation speeds of the drive motor 3 for the wheels 31 and the drive motor 63 for the simulated rail wheels 55,
An arbitrary slip can be given between the wheel 31 and the rail simulation wheel 55. Further, as shown in FIG. 4, nozzles 91 and 93 for spraying air or water to the contact portion between the two wheels may be provided, and the experiment may be performed while changing the friction condition between the two wheels.

Next, the measurement control system of the present apparatus will be described with reference to FIG. The measurement control unit 71 includes a microcomputer and the like. Each of the motors 3,
63, torque meters 35 and 37, the load cell 23, the encoder 33, and the like send signals such as the rotation speed, torque, and current value. Further, the measurement control section 71 sends a control signal to each of the motors 3 and 63 and the cylinders 11 and 21.

The signals from the driving torque meter 35 and the non-driving torque meter 37 are subtracted (or added) by the subtraction unit 73 of the measurement control unit 71. That is, the torque captured by the drive-side torque meter 35 is the sum of the adhesive force torque applied to the wheels 31 and the resistance torque of the anti-drive-side bearing 28, and the torque captured by the anti-drive-side torque meter 37 is Since the torque is the resistance torque of the side bearing 28, the adhesion torque of the wheel 31 can be measured without error by subtracting both torques.

The measurement controller 71 records the adhesion torque and the bearing rotation resistance torque, and after performing a predetermined calculation process and the like, displays a predetermined test result.

FIG. 5 is a diagram schematically showing a configuration of a wheel / rail tester according to another embodiment of the present invention. The features of this embodiment are as follows. (1) No torque meter is provided on the non-drive side of the wheel 31, and torque meters 83 and 81 are provided on the drive side of the wheel 31 and on the motor side of the drive-side bearing 27. this is,
This is because the space around the wheel 31 and the axle 85 is narrow.
If the torque of the torque meter 83 is subtracted from the torque of the torque meter 81, the rotational resistance of the bearing 27 can be obtained. Since the rotational resistance of the bearing 28 is considered to be the same as the rotational resistance of the bearing 27, the adhesive force of the wheel 31 can be substantially obtained by subtracting the rotational resistance of the bearing 27 from the torque of the torque meter 83.

(2) The axle 85 at the torque meter 83 is thin. This is to increase the measurement accuracy by increasing the distortion of the portion. The signal from the torque meter 83 is
5 through the signal line passed through the hole 85a.
Sent to 3. (3) The reference wheel 89 on the right side of the simulated rail wheel 55 measures an absolute difference between the diameter of the simulated rail wheel 55 and the laser by measuring the relative diameter difference with the laser simulated wheel 55, and determines the absolute reference for obtaining the accurate diameter of the simulated rail wheel 55. It is for putting out.

The specifications (example) of the wheel / rail testing machine of the embodiment of FIG. 5 are shown below. Wheel diameter: 300mm Rail simulated wheel diameter: 150-170mm Radial load: ~ 20kN Lateral movement: ± 7mm (3Hz) Wheel peripheral speed: 500km / h Sliding rate: 0-100%

[0036]

As is apparent from the above description, according to the present invention, by subtracting the bearing torque from the driving torque or braking torque of the rotating shaft, the torque based on the adhesive force, and hence the adhesive force, can be obtained more accurately. Can be measured. The resistance torque of the bearing is accurate because it is an actually measured value at the time of the load and the number of rotations during the test. According to the bearing rotational resistance measuring device of the present invention, it is possible to measure the bearing resistance when the load state, the rotational speed, and the cumulative rotational speed of the bearing change. Therefore, a new performance evaluation criterion can be provided for a bearing in which only the standard values for the maximum load and the maximum number of revolutions have been conventionally known. In particular, in the case of railway wheel bearings, it is possible to grasp the amount of increase in the running resistance value depending on the occupancy rate for each train set, and thus very important data can be obtained in terms of the operation and design of the vehicle.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a configuration of a wheel / rail tester according to one embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a measurement control system of the wheel / rail tester of FIG.

FIG. 3 is a diagram illustrating an attack angle.

FIG. 4 is a diagram showing a method of changing experimental conditions of the wheel / rail tester of FIG.

FIG. 5 is a view schematically showing a configuration of a wheel / rail testing machine according to another embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 1 wheel / rail testing machine 3 DC motor 5 connecting shaft 7 constant velocity joint 9 pressing mechanism 11 pressing cylinder 13 vertical linear guide 15 vertical moving frame 17 horizontal moving linear guide 19 left / right moving frame 21 lateral moving cylinder 23 load cell 25 bearing frame 27 drive Side bearing 28 Non-drive side bearing 29 Thermometer 31 Wheel 33 Axle 35 Drive side torque meter 37 Non-drive side torque meter 41 Encoder 43 Slip ring 51, 57 Bearing 53 Shaft 55 Simulated rail wheel 59 Frame 61 Diaphragm coupling 63 DC motor 65 Bed 67 Actuator 81 Motor torque meter 83 Axle torque meter 85 Axle 89 Reference wheel 91, 93 Nozzle

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Takuya Honto, 2-8-8 Hikaricho, Kokubunji, Tokyo Metropolitan Institute of Technology (72) Inventor Eiichi Maebashi 2-8-8 Hikaricho, Kokubunji, Tokyo 38 F-term in the Railway Technical Research Institute (reference) 2F051 AA01 AB01 AB09 AC04 BA03 BA07

Claims (14)

[Claims] A first rotating body; a bearing for supporting the first rotating body; a driving mechanism for rotating the first rotating body at a first peripheral speed; a second rotating body; A driving mechanism for rotating the second rotating body at a second peripheral speed; and a pressing mechanism for applying a pressing force between the outer periphery of the first rotating body and the outer periphery of the second rotating body. A load cell for measuring the pressing force, a driving torque meter for measuring the driving torque of the first rotating body, and a resistance torque meter for measuring the resistance torque of a bearing supporting the first rotating body. A rotary contact resistance measuring device, comprising: A first rotating body; a bearing for supporting the first rotating body; a driving mechanism for rotating the first rotating body at a first peripheral speed; a second rotating body; A driving mechanism for rotating the second rotating body at a second peripheral speed; and a pressing mechanism for applying a pressing force between the outer periphery of the first rotating body and the outer periphery of the second rotating body. A load cell for measuring the pressing force; a driving torque meter for measuring a driving torque of the first rotating body; and a periodically rotating the first rotating body and the second rotating body substantially in a rotation axis direction. A rotary contact resistance measuring device comprising a horizontal moving mechanism or a rotating mechanism for moving. 3. The apparatus according to claim 1, further comprising a lateral movement mechanism or a rotation mechanism for periodically moving the first rotator and the second rotator relative to each other in a rotation axis direction. Rotary contact resistance measuring device. 4. A first rotating body, a bearing for supporting the first rotating body, a drive mechanism for rotating the first rotating body at a first peripheral speed, a second rotating body, A driving mechanism for rotating the second rotating body at a second peripheral speed; and a pressing mechanism for applying a pressing force between the outer periphery of the first rotating body and the outer periphery of the second rotating body. A load cell for measuring the pressing force, a driving torque meter for measuring a driving torque of the first rotating body, and a twist mechanism for twisting the rotating shafts of the first rotating body and the second rotating body. A rotary contact resistance measuring device. 5. The rotating contact resistance measuring device according to claim 1, further comprising a twist mechanism for twisting the rotation axes of the first rotating body and the second rotating body. 6. The apparatus according to claim 1, further comprising a contact angle imparting mechanism for mutually inclining the rotation axes of said first rotating body and said second rotating body. Rotary contact resistance measuring device. 7. The method according to claim 1, wherein the first rotating body is a simulated railway wheel, and the second rotating body is a simulated railway rail.
The rotational contact resistance measuring device according to any one of claims 1 to 6. 8. A shaft fitted to the inner ring of the bearing, a pressing mechanism for applying a radial load to the outer ring of the bearing, a driving mechanism for rotating the shaft at an arbitrary speed, and a shaft between the bearing and the driving mechanism. A bearing rotational resistance measuring device, comprising: a resistance torque meter for measuring a bearing resistance torque. 9. The bearing rotational resistance measuring device according to claim 8, further comprising a mechanism for applying a thrust load to the bearing. 10. A first rotating body, a bearing for supporting the first rotating body, a drive mechanism for rotating the first rotating body at a first peripheral speed, a second rotating body, A driving mechanism for rotating the second rotating body at a second peripheral speed; and a pressing mechanism for applying a pressing force between the outer periphery of the first rotating body and the outer periphery of the second rotating body. A load cell that measures the pressing force; and a resistance torque meter that measures a resistance torque of a bearing that supports the first rotating body. 11. The apparatus according to claim 10, further comprising a lateral movement mechanism or a rotation mechanism for periodically moving the first rotator and the second rotator relative to each other in a rotation axis direction. Bearing rotation resistance measuring device. 12. The bearing rotation resistance measuring device according to claim 10, further comprising a twist mechanism for twisting a load on the first rotating body and the second rotating body. 13. The device according to claim 10, further comprising a contact angle imparting mechanism for inclining the rotation axes of the first rotating body and the second rotating body with respect to each other. Rotary contact resistance measuring device. 14. The simulated railway wheel, the first rotator is a simulated railroad rail, and the bearing is a simulated axle bearing.
14. The rotary contact resistance measuring device according to any one of 13).