Transmission device with low wear rate and tire uniformity testing machine

Abstract

The utility model discloses a low-wear-rate transmission device and a tire uniformity testing machine. The low-wear-rate transmission device comprises a servo motor and a speed reducer, the coupling is arranged between the transmission shaft and the input hole and can transmit the torque of the transmission shaft to the input hole; the connecting flange is arranged between the servo motor and the speed reducer, an observation window is formed in the connecting flange, and the projection of the observation window can respectively cover the connecting part of the transmission shaft and the coupler. The transmission shaft is fixedly connected with the inlaid matching shaft through the coupler, the coupler is connected with the transmission shaft and the inlaid matching shaft in a fastening mode through bolts of the coupler in a fastening and adjusting mode, the coupler can transmit torque output by the transmission shaft to the inlaid matching shaft through friction, and then the inlaid matching shaft transmits the torque to the speed reducer. The speed reducer converts rotary motion into reciprocating linear motion of the load drum, the abrasion condition of a transmission shaft and an input hole when the servo motor changes the rotation state of the servo motor at high frequency is relieved, and the service life of the transmission device is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of tire uniformity detection, in particular to a transmission device with a low wear rate and a tire uniformity testing machine. Background Art

[0002] The tire uniformity tester is mainly used to measure the radial force fluctuation and lateral force fluctuation of the tire when the tire rotates at high speed and bears load, so as to reflect the unevenness of the tire mass distribution, and then measure and evaluate the mass distribution and thickness changes at different positions of the tire, which is also a direct indicator for evaluating the uniformity of the tire. The tester includes a main shaft that clamps the tire and keeps it rotating stably, a load drum that simulates direct contact between the road surface and the tire, a transmission device responsible for adjusting the contact pressure and position between the tire and the load drum, a uniformity measurement unit that measures the various mechanical properties of the tire during rotation, and a control system that controls the motion state of each moving part.

[0003] The existing tire uniformity tester performs a running test on the tire including: adjusting the initial position between the tire and the load drum and loading the specified load, setting tire test parameters, collecting data generated during the test, forward and reverse rotation test, data analysis and reporting. During the loading of the specified load, the control system controls the transmission device to approach the tire until it reaches the specified position. According to the feedback data from the force sensor, displacement sensor, etc., the transmission device is continuously controlled to control the load drum to approach and move away from the tire until the force between the load drum and the tire reaches the specified load requirement. At the same time, during the forward and reverse rotation test, the control system needs to control the transmission device to control the distance between the load drum and the tire so that the load drum and the tire remain in contact or non-contact state.

[0004] The inventor of the present application discovered during the running test that the existing transmission device drives the worm gear reducer through a servo motor, thereby pushing the load drum closer to or away from the tire. The servo motor needs to continuously accelerate to high speed, decelerate to low speed, and rotate forward and reverse within 25 seconds. The instantaneous torque applied by the drive shaft of the servo motor to the input hole of the worm gear reducer is extremely large. However, the connection method between the existing servo motor drive shaft and the input hole of the worm gear reducer is a flat key connection. The flat key connection relies on the two side faces of the key to fit tightly with the keyway on the shaft and the two side faces of the keyway on the input hole of the reducer, and transmits torque through extrusion. When the torque acts on the key, the side faces of the key will be affected by shear force, thereby transmitting the torque from the shaft As for the input hole of the reducer, the inventor of the present application found that when a flat key is used for connection under extremely large instantaneous torque, the keyway of the existing servo motor drive shaft and the keyway of the reducer input hole are very prone to wear, which makes the wear of the transmission device more serious. It is necessary to frequently replace the flat key, servo motor drive shaft and repair the reducer input hole. At the same time, the existing transmission device cannot intuitively observe the wear of the flat key, drive shaft and reducer input hole, which makes it impossible for the inventor of the present application to detect the occurrence of wear in time and replace components in time to reduce the deviation in the corresponding relationship between the load and position applied by the load drum to the tire due to the wear of the transmission device, which increases the number of times the load drum fine-tunes the position and reduces the test efficiency of the tire uniformity tester. Utility Model Content

[0005] The utility model provides a transmission device with low wear rate and a tire uniformity tester to solve the problem of high wear rate of the existing transmission device. The specific technical scheme is as follows:

[0006] A transmission device with a low wear rate includes a transmission device body, which includes a servo motor and a reducer, and also includes: a coupling arranged on the transmission shaft of the servo motor and the input hole of the reducer, the coupling can transmit the torque of the transmission shaft to the input hole; and a connecting flange arranged between the servo motor and the reducer, the connecting flange is formed with an observation window in the axial direction, and the projection of the observation window in the radial direction of the coupling can at least cover the connection part between the transmission shaft and the coupling.

[0007] Preferably, the transmission device body further comprises a fitting shaft arranged between the coupling and the input hole, the fitting shaft is coaxial with the input hole and the coupling, and the coupling transmits the torque of the transmission shaft to the input hole through the fitting shaft.

[0008] Preferably, the axis of the coupling coincides with the axis of the transmission shaft and the axis of the input hole.

[0009] Preferably, the maximum torque of the coupling is greater than the maximum torque output by the transmission shaft.

[0010] Preferably, the connection flange forms a cavity, the projection of the cavity in the axial direction of the coupling can completely cover the coupling, and the projection of the observation window in the radial direction of the coupling also needs to cover the connection portion between the coupling and the input hole.

[0011] A tire uniformity tester comprises: a transmission device body; a load drum connected to the output shaft of a reducer; a main shaft, the plane formed by the axis of the main shaft and the axis of the load drum is perpendicular to the horizontal plane; and a control system, which can control the transmission device body to drive the load drum to approach or move away from the main shaft.

[0012] Preferably, the transmission device body converts the rotational motion into reciprocating linear motion of the load drum approaching or moving away from the main shaft through a screw transmission mechanism.

[0013] It can be seen from the above technical solution that the utility model has the following beneficial effects:

[0014] The utility model fixes the transmission shaft and the matching shaft of the servo motor together through a coupling, wherein the coupling is fastened to the transmission shaft and the matching shaft by means of its own bolt tightening and adjustment, so that the coupling can transmit the torque output by the transmission shaft to the matching shaft by means of friction, and the matching shaft welded to the input hole of the reducer transmits the torque to the reducer, and the reducer then drives the screw transmission structure to convert the rotational motion into the reciprocating linear motion of the load drum, thereby reducing the wear of the transmission shaft and the input hole when the servo motor changes its own rotation state at high frequency, and prolongs the service life of the transmission device; secondly, the servo motor and the reducer are fixedly connected by a connecting flange, so that the coupling only bears torque but not other external forces, thereby prolonging the service life of the coupling; in addition, an observation window is formed on the side of the connecting flange, through which the operator can observe the connection and transmission conditions of the coupling with the transmission shaft and the matching shaft respectively, so that the operator can promptly discover the mechanism failure and avoid greater damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a structural schematic diagram of the first embodiment of the utility model.

[0016] In the figure: 1. Transmission device body; 11. servo motor; 12. transmission shaft; 13. reducer; 14. input hole; 15. coupling; 16. matching shaft; 17. connecting flange; 18. cavity; 19. observation window. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] In the description of the embodiments of the present invention, it should be noted that the terms "inside", "outside", "upper", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0019] Embodiment 1

[0020] like Figure 1 As shown, this embodiment includes a transmission device body 1, which includes a servo motor 11 and a reducer 13. The transmission device body 1 also includes: a coupling 15 arranged on the transmission shaft 12 of the servo motor 11 and the input hole 14 of the reducer 13, and the coupling 15 can transmit the torque of the transmission shaft 12 to the input hole 14; and a connecting flange 17 arranged between the servo motor 11 and the reducer 13, and the connecting flange 17 is formed with an observation window 19 in the axial direction, and the projection of the observation window 19 in the radial direction of the coupling 15 can at least cover the connection part between the transmission shaft 12 and the coupling 15.

[0021] Specifically, the output torque of the servo motor 11 is transmitted to the reducer 13. In this embodiment, the reducer 13 is a worm gear reducer 13, which can convert the high-speed and low-torque output of the servo motor 11 into a low-speed and high-torque output of the reducer 13 through a low transmission ratio; secondly, the diameter of the two ends of the coupling 15 can be adjusted by bolts, and then fixedly connected to the drive shaft 12 and the input hole 14. It transmits torque through the friction force of the inner and outer surfaces, and can make the output torque of the drive shaft 12 be transmitted to the input hole 14 without loss, and it can always maintain the relative position with the drive shaft 12 and the input hole 14 unchanged when the torque output by the drive shaft 12 changes at a high frequency, so as to avoid relative movement and wear. Therefore, the coupling 15 can avoid wear of the drive shaft 12 and the input hole 14 under high-frequency torque changes by transmitting torque through friction, thereby reducing the wear rate of the transmission device.

[0022] Secondly, the left and right ends of the connecting flange 17 are connected to the servo motor 11 and the reducer 13 by bolt connection, so that the relative position between the servo motor 11 and the reducer 13 remains unchanged, and the position of the observation window 19 relative to the drive shaft 12 and the coupling 15 remains unchanged. The operator can observe the transmission conditions of the left end of the drive shaft 12 and the coupling 15 through the observation window 19, such as whether the drive shaft 12 is still rotating, whether the coupling 15 rotates synchronously with the drive shaft 12, whether the coupling 15 breaks due to exceeding its maximum torque, and most importantly, when the drive shaft 12 is stationary, the operator can easily observe whether the drive shaft 12 and the coupling 15 are worn. If wear occurs, the cause should be found and improved in time, thereby reducing the wear rate of the transmission device.

[0023] Furthermore, the transmission device body 1 also includes a fitting shaft 16 disposed between the coupling 15 and the input hole 14 . The fitting shaft 16 is coaxial with the input hole 14 and the coupling 15 . The coupling 15 transmits the torque of the transmission shaft 12 to the input hole 14 via the fitting shaft 16 .

[0024] Specifically, the left end of the matching shaft 16 is fixedly connected to the right end of the coupling 15 by bolting, and the right end of the matching shaft 16 is fixedly connected to the input hole 14 by welding, so that the matching shaft 16 can synchronously transmit the torque transmitted by the coupling 15 to the input hole 14, and then transmit it to the reducer 13; secondly, the matching shaft 16, the input hole 14 and the coupling 15 are coaxial, which can enable them to transmit torque without loss. When the matching shaft 16 is not coaxial with them, the matching shaft 16 will rotate eccentrically during the rotation process, which will not only increase energy loss but also increase component wear.

[0025] Furthermore, the axis of the coupling 15 coincides with the axis of the transmission shaft 12 and the axis of the input hole 14 .

[0026] Specifically, the axes of the coupling 15, the transmission shaft 12 and the input hole 14 coincide with each other, that is, the axes of the coupling 15, the transmission shaft 12, the input hole 14 and the matching shaft 16 coincide with each other, and the torque rotation center does not shift, so that the torque transmitted by the three is always consistent, thereby transmitting the torque without loss and ensuring the transmission efficiency of the transmission device.

[0027] Furthermore, the maximum torque of the coupling 15 is greater than the maximum torque output by the transmission shaft 12 .

[0028] Specifically, the parameters of the coupling 15 include the maximum torque. When the torque between the servo motor 11 and the reducer 13 exceeds the maximum torque, the coupling 15 breaks, disconnecting the servo motor 11 and the reducer 13, thereby preventing the servo motor 11 and the reducer 13 from being damaged due to excessive torque.

[0029] Furthermore, the connection flange 17 is formed with a cavity 18 , and the projection of the cavity 18 in the axial direction of the coupling 15 can completely cover the coupling 15 .

[0030] Specifically, there is always a gap between the outer circumference of the coupling 15 and the inner circumference of the connecting flange 17, which can prevent the coupling 15 from rubbing against the connecting flange 17 during rotation, which not only wears the coupling 15 but also loses part of the torque.

[0031] Furthermore, the projection of the observation window 19 in the radial direction of the coupling 15 also needs to be able to cover the connection portion between the coupling 15 and the input hole 14 .

[0032] Specifically, the caliber of the observation window 19 on the connecting flange 17 can be reduced by opening two calibers, so that the operator can observe the conditions at both ends of the coupling 15 without affecting the structural strength of the coupling 15. One window is used to observe the connection between the coupling 15 and the mating shaft 16, and the other window is used to observe the connection between the coupling 15 and the transmission shaft 12. This allows the operator to always understand the transmission condition of the transmission device and the wear condition of the transmission shaft 12 and the mating shaft 16, and facilitates the timely disassembly of the connecting flange 17 for replacement.

[0033] Embodiment 2

[0034] This embodiment includes: the transmission device body 1 in embodiment one; a load drum connected to the output shaft of the reducer 13 in embodiment one; a main shaft, the plane formed by the axis of the main shaft and the axis of the load drum is perpendicular to the horizontal plane; and a control system, which controls the transmission device body 1 to drive the load drum closer to or away from the main shaft.

[0035] Specifically, in the process of evaluating the uniformity of the tire, the control system controls the output speed and rotation direction of the transmission device body 1 according to the set tire load, and then controls the load drum to approach the tire to apply pressure thereto, so that the tire reaches the specified load. The rotation of the main shaft drives the tire that has reached the specified load to rotate, and then the radial force fluctuation and lateral force fluctuation of the tire are measured to reflect the unevenness of the tire mass distribution, and then the mass distribution and thickness changes at different positions of the tire are measured and evaluated, wherein the axes of the load drum and the main shaft are perpendicular to the horizontal plane, so that the radial force received by the tire during rotation has no gravity component to affect the experimental data, thereby improving the accuracy of the measurement data of this embodiment.

[0036] Furthermore, the transmission device body 1 converts the rotational motion into a reciprocating linear motion of the load drum approaching or moving away from the main shaft through the screw transmission mechanism.

[0037] Specifically, the screw transmission mechanism can convert the rotation of the reducer output shaft into the linear movement of the load drum, wherein the control system continuously controls the distance between the load drum and the main shaft, that is, the distance between the outer surface of the load drum and the outer surface of the tire, according to the set tire load and the real-time data measured by the sensor, so as to ensure that the load on the tire is within the required range.

[0038] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0039] The technology, shape and structure parts not described in detail in the present invention are all known technologies.

Claims

1. A transmission device with a low wear rate, comprising a transmission device body (1), wherein the transmission device body (1) comprises a servo motor (11) and a reducer (13), characterized in that: The transmission device body (1) further comprises: A coupling (15) disposed on the transmission shaft (12) of the servo motor (11) and the input hole (14) of the reducer (13), wherein the coupling (15) is capable of transmitting the torque of the transmission shaft (12) to the input hole (14); and A connecting flange (17) is arranged between the servo motor (11) and the reducer (13), and an observation window (19) is formed on the connecting flange (17) along the axial direction. The projection of the observation window (19) in the radial direction of the coupling (15) can at least cover the connection portion between the transmission shaft (12) and the coupling (15).

2. The transmission device according to claim 1, characterized in that: The transmission device body (1) also includes a mating shaft (16) arranged between the coupling (15) and the input hole (14); the mating shaft (16) is coaxial with the input hole (14) and the coupling (15); the coupling (15) transmits the torque of the transmission shaft (12) to the input hole (14) through the mating shaft (16).

3. The transmission device according to claim 2, characterized in that: The axis of the coupling (15) coincides with the axis of the transmission shaft (12) and the axis of the input hole (14).

4. The transmission device according to claim 3, characterized in that: The maximum torque of the coupling (15) is greater than the maximum torque output by the transmission shaft (12).

5. The transmission device according to claim 1, characterized in that: The connecting flange (17) is formed with a cavity (18), and the projection of the cavity (18) in the axial direction of the coupling (15) can completely cover the coupling (15).

6. The transmission device according to claim 5, characterized in that: The projection of the observation window (19) in the radial direction of the coupling (15) also needs to be able to cover the connection portion between the coupling (15) and the input hole (14).

7. A tire uniformity testing machine, characterized in that: include: The transmission device body (1) according to any one of claims 1 to 6; A load drum connected to the output shaft of the reducer (13) according to claim 1; a main shaft, the plane formed by the axis of the main shaft and the axis of the load drum being perpendicular to the horizontal plane; and A control system is provided, wherein the control system can control the transmission device body (1) to drive the load drum to approach or move away from the main shaft.

8. The tire uniformity testing machine according to claim 7, characterized in that: The transmission device body (1) converts the rotational motion into reciprocating linear motion of the load drum approaching or moving away from the main shaft through a screw transmission mechanism.

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