Adjustable inerter based on differential transmission and control method

Abstract

The invention discloses an adjustable inerter based on differential transmission and a control method. The adjustable inerter comprises a shell, an electromagnetic clutch arranged in the shell, a flywheel connected with the electromagnetic clutch, an output bevel gear connected with the flywheel, planetary bevel gears arranged on the two sides of the output bevel gear and connected with the output bevel gear in a meshed mode, an input bevel gear connected with the planetary bevel gears in a meshed mode and a lead screw connected with the input bevel gear. A rotor shell is arranged on the outer side of the input bevel gear, a rotor gear shaft is arranged between the planetary bevel gears on the two sides, the two ends of the rotor gear shaft are installed in the rotor shell, a rotor magnet is arranged on the outer side of the rotor shell, and a rotor magnet is arranged on the outer side of the rotor magnet. A stator winding is fixedly arranged in the shell corresponding to the rotor magnet; fixed lifting lugs are arranged at the upper end of the shell and the lower end of the lead screw nut; the method has the beneficial effect that different requirements of a quasi-zero stiffness inerter control strategy on the inertia force of the suspension are met.

Description

Technical Field

[0001] The invention relates to the technical field of engineering vibration isolation, in particular to an adjustable inertia container based on differential transmission and a control method thereof. Background Art

[0002] As an end-point inertial element, the introduction of the inertial chamber provides a new idea for the innovative development of vibration isolation technology; the introduction of the inertial chamber into the vehicle suspension system provides mass impedance characteristics for the traditional suspension structure based on "spring-damper", effectively improving the vibration isolation performance of the vehicle suspension system; among them, the implementation forms of the inertial chamber include ball screw type, gear rack type and hydraulic type; the quasi-zero stiffness vibration isolation theory has excellent performance in the field of engineering vibration isolation due to its characteristic that the dynamic stiffness tends to zero. Existing quasi-zero stiffness vibration isolators generally bear the load with a positive stiffness spring, and the negative stiffness mechanism offsets the stiffness of the positive stiffness spring, so that the dynamic stiffness of the system tends to zero; the positive stiffness is generally provided by a spring, and the negative stiffness mechanism has many forms, such as inclined or horizontal springs, electromagnetic springs, bi-stable laminates, diamond mechanisms and X-shaped mechanisms;

[0003] Defects and drawbacks of current technology: During vehicle driving, the load, speed, road conditions and other driving conditions will change greatly, and different working conditions have different requirements for vehicle ride comfort and handling stability, and the suspension characteristics must also change accordingly; the application of quasi-zero stiffness control can effectively improve the suspension vibration isolation performance, but the existing quasi-zero stiffness isolators have problems such as complex structure and difficult installation, and the passive inertia container structural parameters are fixed, and the inertia coefficient cannot be continuously adjusted, which cannot meet the vibration isolation requirements of vehicles under various working conditions;

[0004] In view of the above situation, it is necessary to improve the existing vibration isolation technology so that it can adapt to the current needs of vehicle vibration isolation. Summary of the invention

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is an adjustable inertia container based on differential transmission, comprising a shell, an electromagnetic clutch arranged in the shell, a flywheel connected to the electromagnetic clutch, an output bevel gear connected to the flywheel, planetary bevel gears arranged on both sides of the output bevel gear and respectively meshed with the output bevel gears, an input bevel gear meshed with the planetary bevel gears, a lead screw connected to the input bevel gear, a lead screw nut arranged on the lead screw and connected to the lead screw, the lead screw nut and the lead screw form a ball screw pair, a rotor shell is provided on the outside of the planetary bevel gears, the output bevel gear and the input bevel gear, a rotor gear shaft is provided between the planetary bevel gears on both sides, two ends of the rotor gear shaft are installed in the rotor shell, a rotor magnet is provided on the outside of the rotor shell, a stator winding is fixedly provided in the shell corresponding to the position of the rotor magnet, and fixing ears are provided at the upper end of the shell and the lower end of the lead screw nut.

[0006] As a further supplement to the technical solution, the input bevel gear is fixedly connected to the upper end of the lead screw and is connected to the inner surface of the housing through a lead screw bearing.

[0007] As a further supplement to the technical solution, the output bevel gear is fixedly connected to one end of the flywheel and is connected to the inner surface of the housing through a flywheel bearing.

[0008] As a further supplement to the technical solution, the other end of the flywheel is fixedly connected to the input end of the electromagnetic clutch and the output end of the electromagnetic clutch is fixedly connected to the housing.

[0009] As a further supplement to the technical solution, the planetary bevel gear is connected to the rotor gear shaft via a bearing, and both ends of the rotor gear shaft are fixedly mounted on the rotor housing.

[0010] As a further supplement to the technical solution, the rotor housing is connected to the input bevel gear and the output bevel gear respectively through two upper and lower rotor bearings.

[0011] As a further supplement to the technical solution, the rotor magnet is fixedly mounted on the rotor housing.

[0012] As a further supplement to the technical solution, the stator winding, the rotor magnet and the rotor housing together constitute a rotating electrical machine.

[0013] A control method for an adjustable inertia container based on differential transmission includes three working modes: a semi-active control mode, an energy feeding mode, and an active control mode.

[0014] As a further supplement to the technical solution, the specific control method of the semi-active control mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch is disconnected, the flywheel and the output bevel gear have the freedom to rotate relative to the housing, the lead screw nut performs linear motion relative to the housing, driving the lead screw and the input bevel gear to rotate around their own axes, and the input bevel gear drives the planetary bevel gears, the output bevel gear and the flywheel to rotate around their own axes, thereby realizing inertial packaging; when current flows through the stator winding, according to the law of electromagnetic induction, the rotor magnet drives the rotor housing to rotate around its own axis under the action of the magnetic field, thereby driving the planetary bevel gears to rotate around the axis of the rotor housing, changing the transmission ratio between the input bevel gear and the output bevel gear, and realizing a change in the inertia coefficient;

[0015] The specific control method of the energy feeding mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch is engaged, the flywheel and the output bevel gear are fixedly connected to the housing, and the lead screw nut performs linear motion relative to the housing, driving the lead screw and the input bevel gear to rotate around their own axes. Since the output bevel gear is fixedly connected to the housing and cannot rotate, the input bevel gear drives the planetary bevel gear to rotate while revolving around the rotor housing, driving the rotor housing and the rotor magnet to rotate around their own axes, so that the rotor magnetic field cuts the stator winding, and the stator winding generates a back electromotive force, converting the vibration energy into electrical energy, thereby realizing the recovery of the system vibration energy;

[0016] The specific control method of the active mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch is engaged, the flywheel and the output bevel gear are fixedly connected to the housing, current is passed through the stator winding to generate a magnetic field to drive the rotor magnet and the rotor housing to rotate around their own axis, and the rotor housing drives the planetary bevel gears to rotate while revolving around the rotor housing. Since the output bevel gear is fixedly connected to the housing and cannot rotate, the planetary bevel gear drives the input bevel gear and the screw to rotate around their own axis, and the driving torque of the rotating motor is converted into a linear output force of the screw nut through the ball screw pair, thereby realizing active control of the device.

[0017] Its beneficial effect is that, based on the quasi-zero stiffness inertia control strategy, the electromagnetic clutch engagement and disengagement and the rotation direction of the rotating motor can be controlled, and three different working modes of "semi-active control", "energy feeding" and "active control" can be realized; when the electromagnetic clutch is engaged, the device works in the "energy feeding" mode, using the ball screw to convert the linear motion into the gear rotation motion, driving the rotating motor to rotate, and realizing the vibration energy recovery of the system. Compared with the linear motor, the differential transmission characteristics of the bevel gear can increase the motor energy feeding power. When the electromagnetic clutch is disconnected and the rotating motor and the planetary gear rotate in the same direction, the device operates in a "semi-active control" mode. By controlling the relative speed of the rotating motor and the planetary gear, the rotation speed of the flywheel is changed, and the inertia coefficient of the device is made steplessly adjustable. When the rotating motor and the planetary gear rotate in opposite directions, the device switches to an "active control" mode. The rotating motor acts as a force generator, and the motor torque actively controls the vibration system through bevel gears and ball screws, effectively solving the problem of actively realizing an inertia coefficient less than zero under quasi-zero stiffness control. The present invention meets the different requirements of the quasi-zero stiffness inertia control strategy for the inertia force of the suspension. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a cross-sectional structural diagram of the present invention.

[0019] Figure 2 It is a schematic diagram of the internal structure of the present invention.

[0020] In the figure, 1, housing; 2, electromagnetic clutch; 3, flywheel bearing; 4, flywheel; 5, stator winding; 6, rotor magnet; 7, rotor housing; 8, screw bearing; 9, screw; 10, screw nut; 11, output bevel gear; 12, planetary bevel gear; 13, rotor gear shaft; 14, input bevel gear; 15, rotor bearing. DETAILED DESCRIPTION

[0021] In order to make the technical solution more clear to those skilled in the art, Figure 1-2 The technical solution of the present invention is described in detail:

[0022] like Figure 1 As shown, an adjustable inertia container based on differential transmission includes a housing 1, an electromagnetic clutch 2 arranged in the housing 1, a flywheel 4 connected to the electromagnetic clutch 2, an output bevel gear 11 connected to the flywheel 4, planetary bevel gears 12 arranged on both sides of the output bevel gear 11 and respectively meshed with the output bevel gears 11, an input bevel gear 14 meshed with the planetary bevel gears 12, a lead screw 9 connected to the input bevel gear 14, and a lead screw nut 10 arranged on the lead screw 9 and connected thereto, wherein the lead screw nut 10 and the lead screw 9 form a ball screw pair, a rotor housing 7 is arranged on the outside of the planetary bevel gears 12, the output bevel gear 11, and the input bevel gear 14, a rotor gear shaft 13 is arranged between the planetary bevel gears 12 on both sides, two ends of the rotor gear shaft 13 are installed in the rotor housing 7, a rotor magnet 6 is arranged on the outside of the rotor housing 7, and a stator winding is fixedly arranged in the housing 1 at a position corresponding to the rotor magnet 6. 5, the upper end of the housing 1 and the lower end of the lead screw nut 10 are provided with fixing ears; wherein, the stator winding 5, the rotor magnet 6, and the rotor housing 7 together constitute a rotating motor; the flywheel 4 and the housing 1 can be controlled to be fixed or rotated relatively by connecting or disconnecting the electromagnetic clutch 2; the input bevel gear 14 is fixedly connected to the upper end of the lead screw 9 and is connected to the inner surface of the housing 1 through the lead screw bearing 8; the output bevel gear 11 is fixedly connected to one end of the flywheel 4 and is connected to the inner surface of the housing 1 through the flywheel bearing 3; the other end of the flywheel 4 is fixedly connected to the input end of the electromagnetic clutch 2 and the output end of the electromagnetic clutch 2 is fixedly connected to the housing 1; the planetary bevel gear 12 is connected to the rotor gear shaft 13 through a bearing, and the two ends of the rotor gear shaft 13 are fixedly mounted on the rotor housing 7; the rotor housing 7 is respectively connected to the input bevel gear 14 and the output bevel gear 11 through two upper and lower rotor bearings 15; the rotor magnet 6 is fixedly mounted on the rotor housing 7.

[0023] The control method of the present invention includes three working modes: semi-active control mode, energy feeding mode, and active control mode, which will be described in detail below:

[0024] The specific control method of the semi-active control mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch 2 is disconnected, the flywheel 4 and the output bevel gear 11 have the freedom to rotate relative to the housing 1, the screw 9 and the nut perform linear motion relative to the housing 1, driving the screw 9 and the input bevel gear 14 to rotate around their own axes, and the input bevel gear 14 drives the planetary bevel gear 12, the output bevel gear 11 and the flywheel 4 to rotate around their own axes, thereby realizing inertial packaging; when current flows through the stator winding 5, according to the law of electromagnetic induction, the rotor magnet 6 drives the rotor housing 7 to rotate around its own axis under the action of the magnetic field, thereby driving the planetary bevel gear 12 to rotate around the axis of the rotor housing 7, changing the transmission ratio between the input bevel gear 14 and the output bevel gear 11, and realizing the change of the inertia coefficient;

[0025] In the semi-active mode, the rotation speeds of the input bevel gear 14, the planetary bevel gear 12 and the output bevel gear 11 satisfy the following relationship:

[0026] n1+n3=2n2(1)

[0027] Wherein n1 is the rotation speed of the input bevel gear 14 , n2 is the revolution speed of the planetary bevel gear 12 , and n3 is the rotation speed of the output bevel gear 11 .

[0028] The gear speed is converted into angular velocity to satisfy:

[0029] ω1+ω3=2ω2 (2)

[0030] Wherein ω1 is the angular velocity of the input bevel gear 14, ω2 is the orbital angular velocity of the planetary bevel gear 12, and ω3 is the angular velocity of the output bevel gear 11.

[0031] The relationship between the angular velocity of the input bevel gear 14 and the relative velocity of the two end points of the device is:

[0032]

[0033] Wherein P is the helical lead of the screw 9, and V is the relative speed of the two end points of the device.

[0034] Combining equations (2) and (3), we can obtain:

[0035]

[0036] Affected by the transmission characteristics of the bevel gear, the rotation direction of the flywheel 4 is opposite to that of the input bevel gear 14, so the inertia moment generated by the flywheel 4 is:

[0037]

[0038] Where J is the inertia coefficient of flywheel 4.

[0039] The inertia force converted by the screw nut 10 is:

[0040]

[0041] According to the dynamics formula of inertia vessel:

[0042] F=b(v2-v1) (7)

[0043] The inertia coefficient of the device in the semi-active control mode is obtained as:

[0044]

[0045] Wherein J is the inertia coefficient of the flywheel 4, P is the helical lead of the screw 9, α2 is the angular acceleration of the rotor housing 7, and a is the relative acceleration of the two end points of the device.

[0046] In the specific implementation process, in the semi-active control mode, based on the dynamic principle of quasi-zero stiffness, the variable inertia and the suspension load spring are used to match the stiffness to achieve quasi-zero stiffness control, where the output force F of the variable inertia container is b for:

[0047] F b =b(z s -z u ) (9)

[0048] In the formula, z s is the sprung mass displacement, z u is the unsprung mass displacement.

[0049] To achieve zero dynamic stiffness of the suspension system, it is equivalent to the resultant force of inertia force and elastic force being zero, that is:

[0050] b(z s -z u )+k(z s -z u )=0 (10)

[0051] Therefore, the target value of the inertia coefficient is:

[0052]

[0053] when When b>0, When , it switches to active control mode. The inertia coefficient in semi-active control mode is:

[0054]

[0055] Because z s -z u = 0, the discriminant is meaningless, and (z s -z u )(z s -z u )and The positive and negative signs of are the same, so formula (10) can be further transformed into:

[0056]

[0057] make Then b>0, indicating that the forces at both ends of the inertial container are inversely proportional to the relative acceleration, but the direction is the same as the direction of the relative acceleration. At this time, the inertial container is a semi-active element, which can change the inertia coefficient of the device by controlling the speed change of the rotating motor composed of the stator winding 5, the rotor magnet 6 and the rotor housing 7, thereby realizing "semi-active control".

[0058] The specific control method of the energy feeding mode is as follows: Figure 2 As shown, when performing linear reciprocating motion, the electromagnetic clutch 2 is engaged, the flywheel 4 and the output bevel gear 11 are fixedly connected to the housing 1, and the lead screw 9 and the nut perform linear motion relative to the housing 1, driving the lead screw 9 and the input bevel gear 14 to rotate around their own axes. Since the output bevel gear 11 is fixedly connected to the housing 1 and cannot rotate, the input bevel gear 14 drives the planetary bevel gear 12 to rotate while revolving around the rotor housing 7, driving the rotor housing 7 and the rotor magnet 6 to rotate around their own axes, so that the rotor magnetic field cuts the stator winding 5, and the stator winding 5 generates a back electromotive force, which converts the vibration energy into electrical energy, thereby realizing the recovery of the system vibration energy.

[0059] The specific control method of the active mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch 2 is engaged, the flywheel 4 and the output bevel gear 11 are fixedly connected to the housing 1, and current is passed through the stator winding 5 to generate a magnetic field to drive the rotor magnet 6 and the rotor housing 7 to rotate around their own axes. The rotor housing 7 drives the planetary bevel gears 12 to rotate while revolving around the rotor housing 7. Since the output bevel gear 11 is fixedly connected to the housing 1 and cannot rotate, the planetary bevel gears 12 drive the input bevel gear 14 and the screw 9 to rotate around their own axes, and convert the driving torque of the rotating motor into a linear output force of the screw 9 nut through the ball screw 9 pair, thereby realizing active control of the device.

[0060] In active mode, when And (z s -z u )(z s -z u )and When the positive and negative signs of are the same, b<0, indicating that the forces at both ends of the inertia container are proportional to the relative acceleration, but the direction is opposite to the direction of the relative acceleration. At this time, the inertia container is an active element, and the device switches to the active control mode. Therefore, equation (10) can be further transformed into:

[0061]

[0062] The present invention is based on a quasi-zero stiffness inertia control strategy to control the engagement and disengagement of the electromagnetic clutch and the rotation direction of the rotary motor, and can realize three different working modes of "semi-active control", "energy feeding" and "active control", and meet the different requirements of the quasi-zero stiffness inertia control strategy for the inertia force of the suspension.

[0063] The above technical solutions only reflect the preferred technical solutions of the technical solutions of the present invention. Some changes that may be made to certain parts thereof by technicians in this technical field all reflect the principles of the present invention and fall within the protection scope of the present invention.

Claims

1. An adjustable inertia container based on differential transmission, characterized in that: The invention comprises a housing (1), an electromagnetic clutch (2) arranged in the housing (1), a flywheel (4) connected to the electromagnetic clutch (2), an output bevel gear (11) connected to the flywheel (4), planetary bevel gears (12) arranged on both sides of the output bevel gear (11) and respectively meshingly connected to the output bevel gears (11), an input bevel gear (14) meshingly connected to the planetary bevel gears (12), a lead screw (9) connected to the input bevel gear (14), and a lead screw nut (10) arranged on the lead screw (9) and connected to the lead screw, wherein the lead screw nut (10) is meshed with the lead screw nut. The rod (9) forms a ball screw pair, a rotor housing (7) is provided on the outside of the planetary bevel gear (12), the output bevel gear (11) and the input bevel gear (14), a rotor gear shaft (13) is provided between the planetary bevel gears (12) on both sides, both ends of the rotor gear shaft (13) are installed in the rotor housing (7), a rotor magnet (6) is provided on the outside of the rotor housing (7), a stator winding (5) is fixedly provided in the housing (1) at a position corresponding to the rotor magnet (6), and a fixing lug is provided at the upper end of the housing (1) and the lower end of the screw nut (10).

2. The adjustable inertia container based on differential transmission according to claim 1, characterized in that: The input bevel gear (14) is fixedly connected to the upper end of the lead screw (9) and is connected to the inner surface of the housing (1) via a lead screw bearing (8).

3. The adjustable inertia container based on differential transmission according to claim 1, characterized in that: The output bevel gear (11) is fixedly connected to one end of the flywheel (4) and is connected to the inner surface of the housing (1) via a flywheel bearing (3).

4. The adjustable inertia container based on differential transmission according to claim 1, characterized in that: The other end of the flywheel (4) is fixedly connected to the input end of the electromagnetic clutch (2), and the output end of the electromagnetic clutch (2) is fixedly connected to the housing (1).

5. The adjustable inertia container based on differential transmission according to claim 1, characterized in that: The planetary bevel gear (12) is connected to the rotor gear shaft (13) via a bearing, and both ends of the rotor gear shaft (13) are fixedly mounted on the rotor housing (7).

6. The adjustable inertia container based on differential transmission according to claim 1, characterized in that: The rotor housing (7) is respectively connected to the input bevel gear (14) and the output bevel gear (11) via two upper and lower rotor bearings (15).

7. The adjustable inertia container based on differential transmission according to claim 1, characterized in that: The rotor magnet (6) is fixedly mounted on the rotor housing (7).

8. The adjustable inertia container based on differential transmission according to claim 7, characterized in that: The stator winding (5), the rotor magnet (6) and the rotor housing (7) together constitute a rotating electrical machine.

9. A control method for an adjustable inertia container based on differential transmission according to any one of claims 1 to 8, characterized in that: It includes three working modes: semi-active control mode, energy feeding mode and active control mode.

10. The control method of an adjustable inertia container based on differential transmission according to claim 9, characterized in that: The specific control method of the semi-active control mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch (2) is disconnected, the flywheel (4) and the output bevel gear (11) have the freedom to rotate relative to the housing (1), the lead screw nut (10) performs linear motion relative to the housing (1), drives the lead screw (9) and the input bevel gear (14) to rotate around their own axes, and the input bevel gear (14) drives the planetary bevel gear (12), the output bevel gear (11) and the flywheel (4) to rotate around their own axes, thereby realizing inertial packaging; when current flows through the stator winding (5), according to the law of electromagnetic induction, under the action of the magnetic field, the rotor magnet (6) drives the rotor housing (7) to rotate around its own axis, thereby driving the planetary bevel gear (12) to rotate around the axis of the rotor housing (7), changing the transmission ratio between the input bevel gear (14) and the output bevel gear (11), thereby realizing a change in the inertia coefficient; The specific control method of the energy feeding mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch (2) is engaged, the flywheel (4) and the output bevel gear (11) are fixedly connected to the housing (1), and the lead screw nut (10) performs linear motion relative to the housing (1), driving the lead screw (9) and the input bevel gear (14) to rotate around their own axes. Since the output bevel gear (11) is fixedly connected to the housing (1) and cannot rotate, the input bevel gear (14) drives the planetary bevel gear (12) to rotate while revolving around the rotor housing (7), driving the rotor housing (7) and the rotor magnet (6) to rotate around their own axes, so that the rotor magnetic field cuts the stator winding (5), and the stator winding (5) generates a back electromotive force, converting the vibration energy into electrical energy, thereby realizing the recovery of the system vibration energy; The specific control method of the active mode is as follows: when performing linear reciprocating motion, the electromagnetic clutch (2) is engaged, the flywheel (4) and the output bevel gear (11) are fixedly connected to the housing (1), and current is passed through the stator winding (5) to generate a magnetic field to drive the rotor magnet (6) and the rotor housing (7) to rotate around their own axis. The rotor housing (7) drives the planetary bevel gear (12) to rotate while revolving around the rotor housing (7). Since the output bevel gear (11) is fixedly connected to the housing (1) and cannot rotate, the planetary bevel gear (12) drives the input bevel gear (14) and the lead screw (9) to rotate around their own axis, and the driving torque of the rotating motor is converted into a linear output force of the lead screw nut (10) through the ball screw pair, thereby realizing active control of the device.

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