An energy harvesting and vehicle fault monitoring system for active vibration reduction

Abstract

The present invention discloses an energy collection and vehicle fault monitoring system for active vibration reduction. In the present invention, the slide bar fixed on the upper pressure plate and the lower slide groove constitute a sliding pair; the slide bar is sleeved with a vibration reduction spring; one end of the left and right wing support plates are respectively hinged to the two sides of the lower slide groove; the left ratchet is hinged to the other end of the left wing support plate and connected through a left torsion spring; the right ratchet is hinged to the other end of the right wing support plate and connected through a right torsion spring; the middle of the left and right wing support plates are connected through a balance spring; the ratchet is fixed on the input shaft of a micro-generator; the power output end of the micro-generator is connected to an energy storage battery; the monitoring system collects the electrical signal output by the micro-generator, and monitors and analyzes vehicle faults. The present invention can collect vibration energy within half a cycle of vibration of the vehicle's entire suspension system, has a high energy conversion rate, and has an active vibration reduction effect, can provide a stable output voltage, and can perform fault detection of the vertical stiffness of the suspension without detecting the suspension system.

Description

Technical Field

[0001] The invention belongs to the technical field of micro energy collection, and in particular relates to an active vibration reduction energy collection and vehicle fault monitoring system. Background Art

[0002] With the continuous advancement of social technology, vehicles such as cars, trains, and subways are constantly being put into people's daily lives. However, due to the unevenness of ground facilities or the vibrations generated during vehicle startup and acceleration, they can only be converted into heat and dissipated into the air. On the other hand, with the increasing number of sensors, the lines have become very complicated and maintenance has become very difficult. Some special detection sensors cannot even be directly powered by the vehicle battery. If the vibration energy of the vehicle can be reasonably utilized, it can not only improve energy utilization, power the sensors, simplify the lines, but also improve riding comfort. It can even avoid the suspension system that is difficult to apply the monitoring system, and directly monitor whether the vehicle has a fault in real time based on the change law of the electric energy generated by the vehicle vibration signal. Summary of the invention

[0003] The purpose of the present invention is to provide an active vibration reduction energy collection and vehicle fault monitoring system in response to the vibration energy generated by the vehicle suspension system, collect the vehicle's vibration energy, and use the vehicle's vibration energy to monitor whether the vehicle has any faults.

[0004] The present invention discloses an energy collection and vehicle fault monitoring system for active vibration reduction, comprising an upper pressure plate, a lower slide groove, a left wing support plate, a left pawl, a left torsion spring disk, a right wing support plate, a right pawl, a right torsion spring disk, a ratchet, a balance spring, a micro generator and a monitoring system; a slide bar is fixed to the upper pressure plate, and the slide bar and the top of the lower slide groove form a sliding pair; a vibration reduction spring is sleeved on the slide bar, and the two ends of the vibration reduction spring are respectively fixed to the upper pressure plate and the lower slide groove; one end of the left wing support plate and the right wing support plate are respectively hinged to the two sides of the lower slide groove; the other end of the left wing support plate is fixed to the left torsion spring disk and hinged to the left pawl; the other end of the right wing support plate is fixed to the right torsion spring disk and hinged to the right pawl; the left torsion spring is sleeved on the left torsion spring disk, and one end is hinged to the left torsion spring disk. The left torsion spring disc is fixed, and the other end is fixed to the left pawl; the right torsion spring is sleeved on the right torsion spring disc, one end is fixed to the right torsion spring disc, and the other end is fixed to the right pawl; the left pawl and the right pawl are provided with an integrally formed upper oblique claw finger and a lower oblique claw finger; the ratchet is fixed on the input shaft of the micro-generator and is located at the center position below the left pawl and the right pawl; the base of the micro-generator is fixed to the bottom of the lower slide groove; the middle part of the left wing support plate and the right wing support plate are fixed with a hanging rod, and the two ends of the balance spring are respectively hung on the hanging rods in the middle part of the left wing support plate and the right wing support plate; the power output end of the micro-generator is connected to the energy storage battery; the monitoring system collects the electrical signal output by the micro-generator, and monitors and analyzes vehicle faults.

[0005] Preferably, the monitoring system includes an energy collection module, a background monitoring module and an alarm module; the energy collection module receives the electrical signal transmitted by the wire coil of the micro-generator and transmits it to the background monitoring module; the background monitoring module compares each amplitude in the electrical signal with the stored amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally, records the frequency at which the amplitude of the electrical signal exceeds the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally, and determines whether the frequency exceeds a preset value. If it exceeds the preset value, it is determined that a fault has occurred, and an alarm is issued through the alarm module.

[0006] Preferably, the calculation process of the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally is as follows:

[0007] The differential equation of motion of the dual-mass dynamics model of a single wheel suspension system is:

[0008]

[0009] Among them, m1 is the wheel mass, m2 is the body mass, k1 is the vertical stiffness of the wheel, k2 is the vertical stiffness of the suspension, c2 is the suspension damping coefficient, q is the excitation, x1 is the vertical displacement of the wheel, x2 is the vertical displacement of the body, is the first derivative of x1, is the first derivative of x2, is the second derivative of x1, is the second derivative of x2.

[0010] Before the vibration of a single wheel suspension system is filtered by damping and only the vibration of the vehicle body is considered, the vibration natural frequency of the single degree of freedom undamped free vibration of a single wheel suspension system is solved. The specific process is as follows:

[0011] The motion equation of a single wheel suspension system in undamped free vibration is:

[0012]

[0013] Considering only the vibration of the vehicle body, that is, the wheels are stationary, we get:

[0014]

[0015] The natural frequency of the single-degree-of-freedom undamped free vibration of a single wheel suspension system is The fixed period corresponding to the fixed frequency is

[0016] Since the ratchet only rotates in the first half of the cycle 0.5T, the total displacement s within the ratchet rotation period is half of the total displacement of a single wheel suspension system within a cycle T, and the expression is as follows:

[0017]

[0018] Also because Where w is the angular velocity of the ratchet, l is the rotation radius of the ratchet, then:

[0019]

[0020] Simplified

[0021] The conductor coil of the micro-generator rotates synchronously with the ratchet. Under the action of electromagnetic induction, the conductor coil in the micro-generator moves in a uniform magnetic field to cut the magnetic flux lines. The expression of the magnetic flux change is:

[0022]

[0023] Among them, φ0 is the magnetic flux passing through the conductor coil at time t0, φ is the magnetic flux passing through the conductor coil at time t, B is the magnetic field intensity, S is the area of ​​the conductor coil, θ0 is the initial angle between the conductor coil and the magnetic field direction at time t0, θ is the angle between the conductor coil and the magnetic field direction at time t, and △t is the time difference between time t and time t0.

[0024] When the time △t is very small, the induced electromotive force is approximately expressed as follows:

[0025]

[0026] Since the time △t is very small, the induced electromotive force is further approximated as:

[0027]

[0028] The peak value of the induced electromotive force is This peak value is taken as the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally.

[0029] The present invention has the following beneficial effects:

[0030] 1. Convert the vibration energy generated by the vehicle's suspension system into electrical energy for storage and utilization, solving the energy supply problem of special sensors on the vehicle body that are difficult to connect to the on-board battery.

[0031] 2. The structure in which the left and right pawls are meshed with the ratchet wheel is adopted to convert the reciprocating straight line into a unidirectional rotation, and both the left and right pawls can drive the ratchet wheel to rotate in the same direction, so that the present invention can collect vibration energy within half a cycle of the vibration of the vehicle suspension system, and the energy conversion rate is high.

[0032] 3. The structure of upper pressure plate, slide bar and lower slide groove is adopted, and a vibration reduction spring is arranged on the slide bar, which has an active vibration reduction effect on the rotation of the ratchet wheel, ensures the stability of the output movement, can provide more stable output voltage and power, and has a good assist effect during the vibration return.

[0033] 4. By collecting the vibration energy of the vehicle's suspension system and monitoring the electrical signal transmitted by the wire coil of the micro-generator, it is possible to determine whether there is a fault in the vertical stiffness of the suspension and avoid fault detection in the suspension system where it is difficult to apply the monitoring system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the two-dimensional structure of the present invention when it is not stimulated;

[0035] Figure 2 for Figure 1 Right view of;

[0036] Figure 3 It is a structural stereogram of the present invention when it is not stimulated;

[0037] Figure 4 It is a schematic diagram of the two-dimensional structure of the present invention when it is stimulated and the left and right pawls move to the maximum distance;

[0038] Figure 5 It is a structural stereogram of the left wing support plate, the left pawl and the left torsion spring disc in the present invention;

[0039] Figure 6 The working principle diagram of the micro-generator and the monitoring system in the present invention;

[0040] Figure 7 A dual-mass dynamics model consisting of a vehicle body and wheels. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings.

[0042] like Figure 1 , 2, 3, 4 and 5, an energy collection and vehicle fault monitoring system for active vibration reduction comprises an upper pressure plate 1, a lower slide groove 2, a left wing support plate 3, a left pawl 4, a left torsion spring disc 5, a right wing support plate 9, a right pawl 8, a right torsion spring disc 7, a ratchet 6, a balance spring 10, a micro generator 12 and a monitoring system; a slide bar 11 is fixed on the upper pressure plate 1, and the slide bar 11 and the top of the lower slide groove 2 form a sliding pair; a vibration reduction spring is sleeved on the slide bar 11, and the two ends of the vibration reduction spring are respectively fixed to the upper pressure plate 1 and the lower slide groove 2 to ensure the smoothness of movement during the transmission process and the effect of active vibration reduction; one end of the left wing support plate 3 and the right wing support plate 9 are respectively hinged to the two sides of the lower slide groove 2; the other end of the left wing support plate 3 is fixed to the left torsion spring disc 5 and is connected to the left pawl 4 Hinged; the other end of the right wing support plate 9 is fixed to the right torsion spring disc 7 and hinged to the right pawl 8; the left torsion spring is sleeved on the left torsion spring disc 5, one end of which is fixed to the left torsion spring disc 5, and the other end is fixed to the left pawl 4; the right torsion spring is sleeved on the right torsion spring disc 7, one end of which is fixed to the right torsion spring disc 7, and the other end is fixed to the right pawl 8; the left pawl 4 and the right pawl 8 are both provided with an integrally formed upper oblique claw finger and a lower oblique claw finger; the ratchet 6 is fixed to the input shaft of the micro-generator 12, and is located at the center position below the left pawl 4 and the right pawl 8; the base of the micro-generator 12 is fixed to the bottom of the lower slide groove 2; the middle part of the left wing support plate 3 and the right wing support plate 9 are fixed with a hanging rod, and the two ends of the balance spring 10 are respectively hung on the hanging rods in the middle part of the left wing support plate 3 and the right wing support plate 9. The balance spring 10 is used to restrain the centering of the left and right wing support plates, so that the left pawl 4 and the right pawl 8 are always meshed with the ratchet under the constraint of the balance spring 10 during movement, and one of the pawls will not be squeezed out, and the gap between the left pawl 4 and the right pawl 8 and the ratchet is reduced, and the left torsion spring and the right torsion spring can further reduce the gap between the left pawl 4 and the right pawl 8 and the ratchet. The power output terminal of the micro generator 12 is connected to the energy storage battery, and the power stored in the energy storage battery can power the sensor; the monitoring system collects the electrical signal output by the micro generator 12, and monitors and analyzes vehicle faults.

[0043] As a preferred embodiment, the monitoring system includes an energy collection module, a background monitoring module and an alarm module; the energy collection module receives the electrical signal transmitted by the wire coil of the micro generator 12 and transmits it to the background monitoring module; the background monitoring module compares each amplitude in the electrical signal with the stored amplitude of the electrical signal transmitted by the wire coil when the vehicle is driving normally, records the frequency at which the amplitude of the electrical signal exceeds the amplitude of the electrical signal transmitted by the wire coil when the vehicle is driving normally, and determines whether the frequency exceeds a preset value. If it exceeds the preset value, it is determined that a fault has occurred and an alarm is issued through the alarm module.

[0044] As a preferred embodiment, the calculation process of the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally is as follows:

[0045] Since the vertical vibrations of the suspension systems of the front and rear wheels are almost independent during the cyclic vibration of the vehicle suspension system, a dynamic model can be established for a single wheel suspension system; a single wheel suspension system can be simplified to a dual-mass dynamic model consisting of a vehicle body and wheels, such as Figure 7 As shown, this system model can well reflect the dynamic characteristics of vibrations generated by the vehicle body and wheels, and can be used to monitor whether the vehicle has any faults.

[0046] The differential equation of motion of the dual-mass dynamics model of a single wheel suspension system is:

[0047]

[0048] Among them, m1 is the wheel mass, m2 is the body mass, k1 is the vertical stiffness of the wheel, k2 is the vertical stiffness of the suspension, c2 is the suspension damping coefficient, q is the excitation, x1 is the vertical displacement of the wheel, x2 is the vertical displacement of the body, is the first derivative of x1, is the first derivative of x2, is the second derivative of x1, is the second derivative of x2.

[0049] Before the vibration of a single wheel suspension system is filtered by damping and only the vibration of the vehicle body is considered, the vibration natural frequency of the single degree of freedom undamped free vibration of a single wheel suspension system is solved. The specific process is as follows:

[0050] The motion equation of a single wheel suspension system in undamped free vibration is:

[0051]

[0052] Considering only the vibration of the vehicle body, that is, the wheels are stationary, we get:

[0053]

[0054] The natural frequency of the single-degree-of-freedom undamped free vibration of a single wheel suspension system is The fixed period corresponding to the fixed frequency is

[0055] Therefore, considering only the vehicle body vibration, the displacement of a single wheel suspension system after being stimulated by the outside world and before the vibration is filtered by damping changes according to the sine law with time t. When the displacement is transmitted to the upper pressure plate, it drives the upper pressure plate to vibrate at the same frequency. After it is further transmitted to the ratchet and meshes with the left pawl 4 and the right pawl 8, the vibration frequency changes.

[0056] Since the ratchet only rotates in the first half of the cycle 0.5T, the total displacement s within the ratchet rotation period is half of the total displacement of a single wheel suspension system within a cycle T, and the expression is as follows:

[0057]

[0058] Also because Where w is the angular velocity of the ratchet, l is the rotation radius of the ratchet, then:

[0059]

[0060] Simplified

[0061] The conductor coil of the micro-generator 12 rotates synchronously with the ratchet. Under the action of electromagnetic induction, the conductor coil in the micro-generator 12 moves in a uniform magnetic field (generated by the magnet 13 and the magnet 2 15 that are arranged opposite to each other and have opposite polarities) to cut the magnetic flux lines. The expression of the change of magnetic flux is:

[0062]

[0063] Among them, φ0 is the magnetic flux passing through the conductor coil at time t0, φ is the magnetic flux passing through the conductor coil at time t, B is the magnetic field intensity, S is the area of ​​the conductor coil, θ0 is the initial angle between the conductor coil and the magnetic field direction at time t0, θ is the angle between the conductor coil and the magnetic field direction at time t, and △t is the time difference between time t and time t0.

[0064] Since the magnitude of the induced electromotive force is proportional to the change in magnetic flux and inversely proportional to the time when the magnetic flux change occurs, when the time △t is very small, the induced electromotive force is approximately expressed as follows:

[0065]

[0066] Since the time △t is very small, the induced electromotive force is further approximated as:

[0067]

[0068] The peak value of the induced electromotive force is This peak value is taken as the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally.

[0069] If the monitoring system determines that the amplitude of the electrical signal transmitted by the wire coil of the micro-generator 12 exceeds If the frequency exceeds the preset value, there must be a fault in the vertical stiffness k2 of the suspension, and an alarm should be issued in time to eliminate the hidden danger.

[0070] The active vibration reduction energy collection and vehicle fault monitoring system works as follows:

[0071] The lower slide groove 2 is fixed on the suspension of the vehicle, and the upper pressure plate 1 is fixed on the vehicle body; the upper pressure plate 1 receives the vibration energy from the vehicle's entire suspension system to perform reciprocating motion, pushing the left pawl 4 and the right pawl 8 on both sides to move, thereby causing the left pawl 4 and the right pawl 8 to drive the ratchet to perform rotational motion. During this process, the balance spring, the left torsion spring connected to the left pawl 4, and the right torsion spring connected to the right pawl 8 continuously adjust the elastic force to adjust the angles of the left pawl 4 and the right pawl 8 to ensure that the left pawl 4 and the right pawl 8 are always in close contact with the ratchet; the rotational motion of the ratchet prompts the micro-generator 12 to convert the vehicle's vibration energy into electrical energy, store it in the energy storage battery, and power the sensor. At the same time, the electrical signal of the micro-generator 12 flows through the monitoring system, and the monitoring system monitors and analyzes vehicle faults. When the upper pressure plate makes a progress motion, the left pawl 4 pushes the ratchet wheel to rotate, and the distance between the left and right pawls gradually increases until it reaches a maximum value, and then decreases. The current generated inside the conductor coil 14 flows back to the conductor coil 14 through the commutator 1 17, the brush, the electronic components (sensor), the monitoring system, the brush and the commutator 2 18 in sequence to form a loop. The two brushes are respectively recorded as brush 1 16 and brush 2 19. The two brushes are alternately in contact with the commutator 1 17 and the commutator 2 18. Figure 6 As shown; after the external excitation disappears, the upper pressure plate makes a return motion under the action of the damping spring, the balancing spring, the left torsion spring connected to the left pawl 4 and the right torsion spring connected to the right pawl 8. The right pawl 8 pushes the ratchet to rotate, and the distance between the left and right pawls slowly increases to a maximum value, and then shrinks. The direction of the current generated inside the conductor coil 14 is the same as the direction of the current when the left pawl 4 pushes the ratchet to rotate.

Claims

1. An energy collection and vehicle fault monitoring system for active vibration reduction, comprising an upper pressure plate and a lower slide groove, characterized in that: It also includes a left wing support plate, a left pawl, a left torsion spring disk, a right wing support plate, a right pawl, a right torsion spring disk, a ratchet, a balance spring, a micro-generator and a monitoring system; a sliding rod is fixed to the upper pressure plate, and the sliding rod and the top of the lower slide groove constitute a sliding pair; a damping spring is sleeved on the sliding rod, and the two ends of the damping spring are respectively fixed to the upper pressure plate and the lower slide groove; one end of the left wing support plate and the right wing support plate are hinged to the two sides of the lower slide groove respectively; the other end of the left wing support plate is fixed to the left torsion spring disk and hinged to the left pawl; the other end of the right wing support plate is fixed to the right torsion spring disk and hinged to the right pawl; the left torsion spring is sleeved on the left torsion spring disk, one end is fixed to the left torsion spring disk, and the other end is fixed to the left pawl The right torsion spring is sleeved on the right torsion spring disk, one end of which is fixed to the right torsion spring disk, and the other end of which is fixed to the right pawl; the left pawl and the right pawl are both provided with an integrally formed upper oblique claw finger and a lower oblique claw finger; the ratchet is fixed on the input shaft of the micro-generator and is located at the center position below the left pawl and the right pawl; the base of the micro-generator is fixed to the bottom of the lower slide groove; a hanging rod is fixed to the middle of the left wing support plate and the right wing support plate, and the two ends of the balance spring are respectively hung on the hanging rods in the middle of the left wing support plate and the right wing support plate; the power output end of the micro-generator is connected to the energy storage battery; the monitoring system collects the electrical signal output by the micro-generator, and monitors and analyzes vehicle faults.

2. The active vibration reduction energy collection and vehicle fault monitoring system according to claim 1, characterized in that: The monitoring system includes an energy collection module, a background monitoring module and an alarm module; the energy collection module receives the electrical signal transmitted by the wire coil of the micro generator and transmits it to the background monitoring module; the background monitoring module compares each amplitude in the electrical signal with the stored amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally, records the frequency at which the amplitude in the electrical signal exceeds the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally, and determines whether the frequency exceeds a preset value. If it exceeds the preset value, it is determined that a fault occurs, and an alarm is issued through the alarm module.

3. The active vibration reduction energy collection and vehicle fault monitoring system according to claim 1 or 2, characterized in that: The calculation process of the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally is as follows: The differential equation of motion of the dual-mass dynamics model of a single wheel suspension system is: Among them, m1 is the wheel mass, m2 is the body mass, k1 is the vertical stiffness of the wheel, k2 is the vertical stiffness of the suspension, c2 is the suspension damping coefficient, q is the excitation, x1 is the vertical displacement of the wheel, x2 is the vertical displacement of the body, is the first derivative of x1, is the first derivative of x2, is the second derivative of x1, is the second derivative of x2; Before the vibration of a single wheel suspension system is filtered by damping and only the vibration of the vehicle body is considered, the vibration natural frequency of the single degree of freedom undamped free vibration of a single wheel suspension system is solved. The specific process is as follows: The motion equation of a single wheel suspension system in undamped free vibration is: Considering only the vibration of the vehicle body, that is, the wheels are stationary, we get: The natural frequency of the single-degree-of-freedom undamped free vibration of a single wheel suspension system is The fixed period corresponding to the fixed frequency is Since the ratchet only rotates in the first half of the cycle 0.5T, the total displacement s within the ratchet rotation period is half of the total displacement of a single wheel suspension system within a cycle T, and the expression is as follows: Also because Where w is the angular velocity of the ratchet, l is the rotation radius of the ratchet, then: Simplified The conductor coil of the micro-generator rotates synchronously with the ratchet. Under the action of electromagnetic induction, the conductor coil in the micro-generator moves in a uniform magnetic field to cut the magnetic flux lines. The expression of the magnetic flux change is: Among them, φ0 is the magnetic flux passing through the conductor coil at time t0, φ is the magnetic flux passing through the conductor coil at time t, B is the magnetic field intensity, S is the area of ​​the conductor coil, θ0 is the initial angle between the conductor coil and the magnetic field direction at time t0, θ is the angle between the conductor coil and the magnetic field direction at time t, and △t is the time difference between time t and time t0; When the time △t is very small, the induced electromotive force is approximately expressed as follows: Since the time △t is very small, the induced electromotive force is further approximated as: The peak value of the induced electromotive force is This peak value is taken as the amplitude of the electrical signal transmitted by the wire coil when the vehicle is running normally.

Images