A vibration-damping gear with active control of stiffness

Abstract

The application discloses a damping gear with active control stiffness, and belongs to the field of gear vibration control. The application is used for solving the problems existing in the current gear damping. The application comprises a gear base body, shape memory alloy springs, a lubricating oil groove, a temperature sensor, an electric resistance wire and an end cover. The end cover is fixedly connected with the end face of the gear base body, and covers the groove opening of the lubricating oil groove. The end face of the gear base body is provided with the lubricating oil groove. The m radially telescopic shape memory alloy springs are uniformly distributed along the circumference in the lubricating oil groove. The temperature sensor and the electric resistance wire are symmetrically arranged on the groove bottom of the lubricating oil groove. The electric resistance wire is used for heating the lubricating oil in the lubricating oil groove, so as to control the temperature of the shape memory alloy springs. The spring stiffness is controlled by adjusting the temperature. Finally, the natural frequency of the gear is adjusted, and the purpose of damping is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of active control rigidity gear damping, belong to gear vibration control field. BACKGROUND

[0002] Gear transmission has the advantages of high transmission efficiency, reliable operation, compact structure, etc., and is widely used in transmission systems in the fields of ship, aviation, aerospace, transportation, chemical industry, etc. Gear transmission is often in a complex excitation source environment, and the vibration generated by the gear transmission is one of the main factors affecting the operation of mechanical equipment. Especially when the gear system resonates, the vibration amplitude of the gear system is much higher than that during normal operation, which can cause great harm to the gear transmission system. At the same time, vibration is a common phenomenon in the operation of gear transmission system, although it cannot be completely eliminated, but it can be adjusted to an acceptable safety level. Since the gear rotor device is one of the core components of the transmission system, its vibration directly determines the reliability and stability of the whole equipment. Therefore, how to control the vibration of the gear rotor and then ensure the safe and stable operation of the unit has become a very important and urgent problem in the gear transmission system.

[0003] Domestic and foreign scholars have proposed several measures to control gear vibration:

[0004] (1) Modify the gear, optimize the key parameters of the gear, and thus change the resonance interval of the gear transmission system. In "Research on Gear Modification and Modal Optimization of Centralized Transmission System Based on Genetic Algorithm", Yu Xiaobo modifies the gear microscopically, thereby improving the dynamic characteristics of the gear and avoiding the resonance of the gear transmission system. However, gear modification is usually adopted at the design stage, which is quite different from the actual operation of the gear transmission system, and the effect is not very good; at the same time, many precision gears are modified during the design and manufacturing stage, and it is currently difficult to meet the further low-vibration and low-noise requirements of the gear transmission system. Therefore, it is not an effective vibration reduction method.

[0005] (2) Active and semi-active control method of gear transmission system vibration, this method mainly refers to generating excitation force opposite to the vibration of gear transmission system through additional device to offset the vibration of gear transmission system, the main principle is "vibration reduction by force". Dogruer designed a nonlinear controller with feedforward loop in "Active vibration control of a single-stage spur gearbox", which reduces the meshing vibration of the gear by adjusting the torque acting on the input gear. However, this method only has control effect on vibration of a certain frequency, and has limited vibration control ability for gear rotor system resonance.

[0006] (3) On the gear attached damping vibration structure (such as damping ring, damping layer, etc.) to dissipate the vibration energy of the system, reduce the gear transmission system in the resonance region amplitude. Qiu Zhirui in the bevel gear on the additional damping ring, effectively reduce the gear at the resonance point of the vibration amplitude. But because in the resonance region gear transmission system vibration is usually much larger than the normal work, and damping vibration structure will not change the gear transmission system resonance frequency, so there is still a certain risk, can not completely eliminate the security risks.

[0007] (4) using new materials (such as high polymer composite materials, ceramic materials, magnetic materials, etc.) coated or processed gear, using material properties to absorb, dissipate, reduce the vibration and noise of gear transmission system. But using new materials coated or processed gear manufacturing is not mature, need to consider the cost, processing technology and other factors, so in the engineering practice, the method has great limitations.

[0008] In summary, the gear modification can not completely consider the gear in the engineering practice of various situations, the results may be different from the running results, the method has certain limitations; active control system damping band is narrow, can not eliminate the security risks when resonance; increase damping structure can reduce the resonance amplitude of gear transmission system, but can not eliminate the resonance phenomenon, still exist certain risk; the use of new materials will be subject to cost, process and other factors, difficult to apply in engineering practice. SUMMARY

[0009] In view of the problems existing in the prior art gear damping, the application provides a damping gear with active control stiffness.

[0010] The damping gear with active control stiffness provided by the application comprises a gear base body 8, a shape memory alloy spring 9, a lubricating oil groove 10, a temperature sensor 11, a resistance wire 12 and an end cover 14, the end cover 14 is fixedly connected with the end face of the gear base body 8, and the end cover 14 covers the slot opening of the lubricating oil groove 10.

[0011] The end face of the gear base body 8 is provided with the lubricating oil groove 10, m radially telescopic shape memory alloy springs 9 are uniformly distributed along the circumference in the lubricating oil groove 10, the bottom of the lubricating oil groove 10 is provided with the temperature sensor 11 and the resistance wire 12 which are symmetrically arranged, the resistance wire 12 is used for heating the lubricating oil in the lubricating oil groove 10, thereby controlling the temperature of the shape memory alloy spring 9, controlling the spring stiffness through temperature regulation, finally realizing the adjustment of the natural frequency of the gear, and achieving the purpose of damping.

[0012] Preferably, the shape memory alloy spring 9 is fixed by the conical fixing pin 13, m conical fixing pins 13 are uniformly distributed on the inner side groove wall of the lubricating oil groove 10 in the circumferential direction, and one shape memory alloy spring 9 is installed on each conical fixing pin 13, and the shape memory alloy spring 9 is supported between the inner and outer side groove walls of the lubricating oil groove 10.

[0013] Preferably, the end cover 14 is provided with an oil injection hole 15 and an oil discharge hole 16, and the oil injection hole 15 and the oil discharge hole 16 communicate with the lubricating oil groove 10.

[0014] Preferably, the end cover 14 is bolted to the end face of the gear base 8.

[0015] Preferably, the gear opened in the gear base 8 is a spur gear, a helical gear, a herringbone gear, a bevel gear, a face gear or a planetary gear.

[0016] Preferably, the lubricating oil is turbine oil, dimethyl silicone oil, magnetorheological fluid or dimethyl silicone oil.

[0017] Preferably, the end face of the gear base 8 is provided with the lubricating oil groove 10, which is processed by single-sided machining or double-sided symmetrical machining.

[0018] The beneficial effects of the present application are:

[0019] (1) The structure of the present application is ingenious, the structure is partially designed on the basis of retaining the general structure of the gear, so that the gear with single function has multifunctionality.

[0020] (2) The present application can realize online adjustment of the radial stiffness of the gear during operation by adjusting the temperature of the internal lubricating oil, and can make the natural frequency of the gear rotor avoid the complex excitation frequency of the gear.

[0021] (3) The present application can provide damping for the gear transmission system by using the high damping characteristics of the shape memory alloy, dissipate the vibration energy of the gear transmission system, and play a damping effect.

[0022] (4) The structure of the present application is reasonable, when the key components of the present application are damaged, only the end cover needs to be disassembled for replacement, which greatly improves the maintainability and security of the structure.

[0023] (5) And the present application selects 8 memory alloy springs which are uniformly arranged on both sides of the gear, and the springs on each side are uniformly distributed on the same circumference. Such arrangement not only provides horizontal and vertical stiffness but also provides cross stiffness, thereby improving the running stability of the gear rotor.

[0024] Compared with the existing damping device, the present application has the following advantages:

[0025] (1) The active control stiffness damping gear of the present application can adjust stiffness on line, and has more flexibility compared with the existing damping device, and can adapt to different working environments.

[0026] (2) The present application utilizes the high damping characteristics of the shape memory alloy spring, and compared with the existing damping device, not only can change the stiffness of the gear rotor, but also can improve the damping capacity of the gear transmission system, and plays a certain control role in controlling the vibration of the gear.

[0027] (3) The present application utilizes the approximate linearity of the stiffness and damping of the memory alloy spring with temperature in the temperature range from martensite to austenite, which avoids the nonlinear vibration problem of the traditional damping device. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a structural schematic diagram of a reduction gear box using the active control stiffness damping gear of the present application;

[0029] Figure 2 is an isometric side view of the active control stiffness damping gear of the present application, without end cover;

[0030] Figure 3 is a front view of the active control stiffness damping gear of the present application, without end cover;

[0031] Figure 4 is a front view of the active control stiffness damping gear of the present application, without shape memory alloy spring and end cover;

[0032] Figure 5 is a structural schematic diagram of an end cover of the active control stiffness damping gear of the present application;

[0033] Figure 6 is a flow chart of on-line control stiffness of the active control stiffness damping gear of the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0035] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0036] The present application will be further described below with reference to the drawings and specific embodiments, but is not limited by the present application.

[0037] DETAILED DESCRIPTION Figures 1 to 6 In the embodiment, the active control stiffness damping gear includes a gear base 8, shape memory alloy springs 9, a lubricating oil groove 10, a temperature sensor 11, a resistance wire 12, and an end cover 14 fixedly connected with the end face of the gear base 8, and covering the slot opening of the lubricating oil groove 10.

[0038] The end face of the gear base 8 is provided with the lubricating oil groove 10, and m radially telescopic shape memory alloy springs 9 are uniformly distributed along the circumference in the lubricating oil groove 10.

[0039] The shape memory alloy springs 9 are fixed by conical fixing pins 13, m conical fixing pins 13 are uniformly distributed along the circumference on the inner side groove wall of the lubricating oil groove 10, one shape memory alloy spring 9 is installed on each conical fixing pin 13, and the shape memory alloy spring 9 is supported between the inner and outer side groove walls of the lubricating oil groove 10.

[0040] The end cover 14 is provided with an oil injection hole 15 and an oil discharge hole 16, and the oil injection hole 15 and the oil discharge hole 16 are in communication with the lubricating oil groove 10.

[0041] The end cover 14 and the end face of the gear base 8 are connected by bolts.

[0042] The gear opened on the gear base 8 is a straight gear, a helical gear, a herringbone gear, a bevel gear, a face gear, or a planetary gear.

[0043] The lubricating oil is turbine oil, dimethyl silicone oil, magnetorheological fluid, or dimethyl silicone oil.

[0044] The end face of the gear base 8 is provided with the lubricating oil groove 10, which is processed by single-face processing or double-face symmetrical processing.

[0045] The active control stiffness damping gear can be used in a primary transmission, a secondary transmission, a multi-stage transmission gear system, etc. Figure 1 The active control stiffness damping gear is used in a reduction gear box

[0046] The active control stiffness damping gear can be applied to gear transmission system damping, used in a primary transmission, a secondary transmission, a multi-stage transmission gear system, etc. Figure 1The schematic diagram of the reduction gear box provided with the active control stiffness damping gear of the application. The power is input to the input shaft 1 by the external power source (which can be a motor, a steam turbine, a gas turbine or other power machinery), the input shaft 1 is driven to rotate, and the bearing 2 and the driving gear 3 are driven to rotate. The driving gear 3 drives the driven gear 4 to rotate by meshing, the driven gear 4 drives the output shaft 6 on the bearing 5 to rotate by rotating, and the output shaft 6 outputs the kinetic energy to drive the energy-consuming machinery (such as a generator, a pump, a propeller or the like) to work to complete the transmission. The gear meshing is the main excitation source of the gear transmission system, the vibration is mainly generated with the driving gear 3 and the driven gear 4, and is transmitted to the input shaft bearing 2 and the output shaft bearing 5 through the input shaft 1 and the output shaft 6, and finally the vibration is transmitted to the gear box body 7 and radiated to other equipment. Since the vibration frequency band generated by the gear meshing is complex, the gear transmission system is prone to resonance, which causes great safety risk.

[0047] The active control stiffness damping gear of the application is composed of a gear base body 8, a shape memory alloy spring 9, a lubricating oil groove 10, a temperature sensor 11, a resistance wire 12 and an end cover 14. The gear base body 8 is provided with a conical fixing pin 13 for fixing the shape memory alloy spring 9. The end cover 14 is provided with an oil injection hole 15 and an oil discharge hole 16. The end cover 14 and the gear base body 8 are connected by bolts. Before the active control stiffness damping gear of the application is installed, the shape memory alloy spring 9 needs to be installed on the gear base body 8 first, then the end cover 14 is fastened with the gear base body 8, then the oil discharge hole 16 is plugged with a plug, oil is injected into the lubricating oil groove 10 through the oil injection hole 15 until no oil can be injected, so that the lubricating oil groove 10 is filled with oil, and finally the oil injection hole is plugged with a plug.

[0048] Figure 6 The control flow chart of the active control stiffness damping gear of the application. Before running, the optimal working temperature under different excitation of multiple working conditions is set, so that the natural frequency of the active control stiffness damping gear of the application avoids the excitation frequency of each working condition. The vibration data of the gear are collected in real time during the running of the gear rotor system, and the main frequency components of the vibration are transmitted to the control system. The control system queries the database to obtain the optimal temperature of the shape memory alloy spring 9 corresponding to each vibration frequency and compares it with the actual measured temperature, and calculates the temperature difference. When the temperature difference is not equal to zero, the temperature of the shape memory alloy spring 9 is adjusted by controlling the power of the resistance wire to adjust the stiffness of the gear, until the temperature difference is 0, at which time the vibration data and temperature data of the gear are output. The temperature sensor 11 and the resistance wire 12 can measure and adjust the lubricating oil in the lubricating oil groove 10 online to achieve the purpose of controlling the temperature of the shape memory alloy spring 9. At the same time, the shape memory alloy spring has high damping characteristics, which can provide damping for the gear transmission system and play a damping role.

[0049] The present application controls the rigidity of the shape memory alloy spring 9 by controlling the temperature of the lubricating oil, realizes the regulation and control of the natural frequency of the gear, and avoids the risk of gear resonance. At the same time, the shape memory alloy spring 9 has high damping characteristics and the ability to reduce the vibration of the gear transmission system, and can be widely applied to the gear transmission system, prolonging the service life of key parts such as gears and bearings.

[0050] While the present application has been described herein with reference to particular embodiments thereof, a latitude of modification relative to the specific embodiments described is possible upon reading and understanding the application more fully. Many modifications can be made to the example embodiments described without departing from the spirit and scope of the application as defined in the appended claims. It is therefore intended that such modifications be included within the scope of the application. The disclosure has been presented for purposes of illustration and description but is not intended to be exhaustive or to limit the application to the precise form disclosed. Many modifications, variations, alterations, transformative uses, and equivalent arrangements will be apparent to one skilled in the art once the application has been made. It is the intent that each element that is uniquely described in support of the claims is to be considered as an element that is individually recited in the claims. The patentable scope of the application is defined by the appended claims and their equivalents in which changes can be made.

Claims

1. A vibration damping gear with actively controlled stiffness, characterized in that, It includes a gear base (8), a shape memory alloy spring (9), a lubricating oil groove (10), a temperature sensor (11), a resistance wire (12), and an end cap (14). The end cap (14) is fixedly connected to the end face of the gear base (8) and covers the groove of the lubricating oil groove (10). A lubricating oil groove (10) is provided on the end face of the gear base (8). m radially telescopic shape memory alloy springs (9) are evenly distributed along the circumference inside the lubricating oil groove (10). The shape memory alloy springs (9) are fixed by conical fixing pins (13). m conical fixing pins (13) are evenly distributed along the circumference on the inner side wall of the lubricating oil groove (10). A shape memory alloy spring (9) is installed on each conical fixing pin (13). The shape memory alloy springs (9) are supported between the inner and outer side walls of the lubricating oil groove (10). The bottom of the lubricating oil tank (10) is provided with symmetrically arranged temperature sensors (11) and resistance wires (12). The resistance wires (12) are used to heat the lubricating oil in the lubricating oil tank (10). The tank also includes a control system configured to perform the following operations: A database of the correspondence between different excitation frequencies and the optimal operating temperature of shape memory alloy springs (9) is pre-established and stored; During gear operation, the vibration data of the gear is acquired in real time and its main vibration frequency components are extracted; The corresponding target optimal temperature is obtained by querying the database based on the main vibration frequency components. The actual temperature measured by the temperature sensor (11) is compared with the target optimal temperature, and the heating power of the resistance wire (12) is automatically adjusted according to the comparison result, thereby controlling the temperature of the shape memory alloy spring (9). The spring stiffness is controlled by adjusting the temperature, and finally the natural frequency of the gear is adjusted so that it avoids the excitation frequency, thereby achieving the purpose of vibration reduction. The end cap (14) is provided with an oil injection hole (15) and an oil discharge hole (16), which are connected to the lubricating oil groove (10).

2. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The end cap (14) and the end face of the gear base (8) are connected by bolts.

3. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The gears in the gear base (8) are spur gears, helical gears or herringbone gears.

4. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The gear in the gear base (8) is a bevel gear.

5. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The gear in the gear base (8) is a face gear.

6. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The lubricating oil used is magnetorheological fluid.

7. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The lubricant used is dimethyl silicone oil.

8. The vibration damping gear with actively controlled stiffness according to claim 1, characterized in that, The end face of the gear base (8) is provided with a lubricating oil groove (10) and is machined by single-sided or double-sided symmetrical machining.

Images