DESC:ENERGY HARVESTING SYSTEM USING PIEZO ELECTRIC CELL ACTUATION
Field of the Invention
The present invention relates to an electric energy harvesting and more particularly relates to energy harvesting system using piezoelectric cell actuation and method therefor.
Background of the Invention
Vehicles are subjected to vibrations while being driven due to a variety of road undulations and random road excitations. This causes the vehicle to undergo a significant amount of energy dissipation while compromising fuel economy. In a vehicle, shock absorbers or a combination of shock absorber with leaf springs are mounted to improve the comfort of ride and overcome the undulation of road conditions and rail. As an important part of the vehicle chassis, the suspension system plays a key role in supporting the body and absorbing vibrations, caused by rough road surfaces, while it concentrates the main vibration energy of the vehicle. Vehicle energy loss harvesting technology has a positive significance to the development of the current automotive industry, by improving vehicle energy efficiency, fuel economy, etc. The combination of shock absorber with leaf springs is still improved by the latest trailers and commercial vehicles by separating the trailer portion and the rider seating arrangement in the cabin. Hence suspension is more sensitive to rider than the full truck. Considering the actual requirement of suspension on trailer, it is mainly the leaf spring which takes the load and hydraulic suspension effect is mostly minimized. Currently, the energy associated with these vibrations is lost. However, harvesting and utilizing this energy would provide an additional source of energy that could be used to increase fuel economy.
When certain materials are applied with load they generate electric current. This phenomenon is known as piezoelectric effect and the materials possessing this property are known as piezoelectric materials. Since these materials require some amount of load to operate, attempts have been made for utilizing the property of piezoelectric materials for generation of electric power. However, current technologies do not utilize the vehicle vibrations effectively for generation of power. Hence there is a need to utilize the movement of loaded vehicle to convert the repetitive load application between wheel axle and chassis, which is going as waste energy.
Objects of the invention
The primary object of the present invention is to provide energy harvesting system using piezoelectric cell actuation.
Another object of the present invention is to harvest electrical energy by utilizing vibration energy between wheel axle and chassis of a loaded vehicle.
Summary of the invention
Accordingly the present invention provides a energy harvesting system for a vehicle having a leaf spring suspension and a vehicle frame, that utilizes the vibration energy between wheel axle and chassis of a loaded vehicle for harvesting electrical energy. the energy harvesting system mainly comprises a piezoelectric cell bank fitted between the leaf spring suspension and the vehicle frame, and a energy converter coupled thereto. the piezoelectric cell bank includes a lower plate, and an upper plate fitted one above another using studs. The lower plate is having a bottom surface in contact with the leaf spring and an array of piezoelectric cells fitted on top surface thereof. The upper plate is having a top surface in contact with the vehicle frame and a bottom surface configured with cavities for receiving piezoelectric actuators therein. The plurality of middle plates is fitted between the lower plate and the upper plate. Each middle plate of the plurality of middle plates is configured with cavities on a bottom surface thereof and piezoelectric actuators on a top surface thereof. The piezoelectric cell bank receives vibrations of the leaf spring through the lower plate and generates voltage proportional to the vibrations. The energy converter is coupled to the piezoelectric cell bank for receiving the voltage generated therein, which is further fed to a battery or any other circuit in the vehicle.
Brief description of the drawings
The objective and advantages of the present inventions will become apparent from the following description read in accordance with the accompanying drawings, wherein
Figure 1 shows a perspective view of a energy harvesting system using piezoelectric cell actuation, in accordance with the present invention;
Figure 2 shows exploded view of the energy harvesting system using piezoelectric cell actuation, in accordance with the present invention;
Figure 3 shows a piezoelectric cell unit and exploded view of piezoelectric cell bank of the energy harvesting system, in accordance with the present invention;
Figures 4, 5 and 6 show detailed view of an upper plate, two middle plates and a lower plate of piezoelectric cell bank of the energy harvesting system, in accordance with the present invention.
Detailed description of the present invention
The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.
The present invention provides a electric energy harvesting system using piezoelectric actuation. A piezoelectric cell bank fixed between an unsprung mass and a sprung mass of the vehicle generates voltage proportional to the energy of vibrations in a loaded vehicle due to road undulations.
Leaf spring is a suspension system for vehicles that is used on almost all vehicles like tractors, trucks and vans that haul heavy loads. The spring leaf is made up of an arc-shape, slender piece of steel that is stacked with the same material in smaller sizes and bolted together creating a reinforced bow-like item. It is then attached to the rear axle and the chassis providing support to any additional weight that is added to a vehicle, preventing the axle from buckling in and snapping from the pressure of an extreme amount of weight. The purpose of a leaf spring is to provide support for a vehicle. It also provides for a smoother ride absorbing any bumps or potholes in the road. In the present invention, the energy of vibrations is utilized to produce electric energy by fitting piezoelectric cell bank between the leaf spring and the vehicle chassis/ vehicle frame. the harvested electrical energy can charge the vehicle battery and provide power for the respective load.
The present invention is illustrated with reference to the accompanying drawings, throughout which reference numbers indicate corresponding parts in the various figures. These reference numbers are shown in bracket in the following description. table 1 below enlists the reference numbers and corresponding components indicated by the reference numbers.
Table 1
Ref. No. Component Ref. No. Component
10 Leaf spring suspension 42 Lower plate
20 Vehicle frame 44 Middle plates
30 Shackles 46 Upper plate
40A Piezoelectric actuators 48 Cell bank studs
40B Grooves 50 Piezoelectric cell bank

Referring to figures 1 to 6, there is shown a energy harvesting system (100) (herein after referred as “the system (100)”), using piezoelectric cell actuation in accordance with the present invention.
The system (100) comprises a piezoelectric cell bank (50) and an energy converter. The piezoelectric cell bank (50) is fitted between the leaf spring suspension (10) and the vehicle frame (20). The piezoelectric cell bank (50) is having a lower plate (42), a plurality of middle plates (44) and an upper plate (46) fitted one above another using studs (48).
The lower plate is having a bottom surface in contact with the leaf spring (10) and an array of piezoelectric cells (40A) fitted on a top surface thereof. The upper plate (46) is having a top surface in contact with the vehicle frame (20) and a bottom surface having cavities (40B) configured thereon for receiving piezoelectric actuators (40A) therein. The plurality of middle plates (44) is fitted between the lower plate (42) and the upper plate (46). Each middle plate of the plurality of middle plates (44) is having cavities (40B) on a bottom surface thereof and piezoelectric actuators (40A) on a top surface thereof. In an embodiment, the lower plate (42), the plurality of middle plates (44) and the upper plate (46) are metallic plates.
When unsprang mass vibrates as per road condition, the piezoelectric cell bank (50) receives vibrations of the leaf spring (10) through the lower plate (42) and generates voltage proportional to the vibrations. The energy converter (not shown) is coupled to the piezoelectric cell bank (50) for receiving the voltage generated therein. The amount and consistency of the voltage generated from piezoelectric cell bank (50) depends upon the load that is acting thereon and since the contour of the road is unpredictable, therefore the voltage generated is also varying. The energy converter, the energy converter is a rectifier circuit that filters the voltage received from the piezoelectric cell bank (50) and feed the output to a battery or other electrical system in the vehicle.
The invention effectively uses suspension system while on ride, and also seeks opportunities to extract any other way of benefit during the Suspension operation. The most repetitive function of the suspension is reciprocating movement of one end of the suspension which is a best source of generating energy.
Advantages of the invention
• Vibration because of road variation will be used to generate energy.
• Battery charging of conventional vehicle.
• Utilization of energy to boost the mileage of electric vehicle.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the scope of the present invention.
,CLAIMS:CLAIMS
We claim:
1. A energy harvesting system (100) for a vehicle having a leaf spring suspension (10) and a vehicle frame (20), the energy harvesting system (100) comprising:
a piezoelectric cell bank (50) fitted between the leaf spring suspension (10) and the vehicle frame (20), the piezoelectric cell bank (50) having:
• a lower plate (42) having a bottom surface in contact with the leaf spring (10) and an array of piezoelectric cells (40A) fitted on a top surface thereof;
• an upper plate (46) having a top surface in contact with the vehicle frame (20) and a bottom surface having cavities (40B) configured thereon for receiving piezoelectric actuators (40A) therein;
• a plurality of middle plates (44) fitted between the lower plate (42) and the upper plate (46), each middle plate of the plurality of middle plates (44) having cavities (40B) on a bottom surface thereof and piezoelectric actuators (40A) on a top surface thereof,
wherein the piezoelectric cell bank (50) receives vibrations of the leaf spring (10) through the lower plate (42) and generates voltage proportional to the vibrations; and
a energy converter coupled to the piezoelectric cell bank (50) for receiving the voltage generated therein.
2. The energy harvesting system (100) as claimed in claim 1, wherein the lower plate (42), the plurality of middle plates (44) and the upper plate (46) are metallic plates.
3. The energy harvesting system (100) as claimed in claim 1, wherein the lower plate (42), the plurality of middle plates (44) and the upper plate (46) are fitted one above another using studs (48).
4. The energy harvesting system (100) as claimed in claim 1, wherein the energy converter is a rectifier.
Dated this on 30th day of June 2019

Prafulla Wange
(Agent for the applicant)
(IN/PA-2058)