Final term of mechanical engineering at engineering college, my search for an engineering project idea ended with an idea of designing and fabricating a 12 volt DC hydraulic jack for lifting light motor vehicles. This Hydraulic Jack project is my engineering college project, it was a part of my curriculum and mandatory for partial fulfillment of the requirements for the award of the degree as bachelor of engineering.
Vehicles are lifted for various purposes like for downside inspection or repair, replacement of tyres etc. On service stations both manual hand operated and automatic hydraulic jacks are used to lift the vehicles. But on the road, for tyre replacement, driver have to put efforts with conventional hand operated jacks present in the vehicle.
The objective of this hydraulic jack project was to design, fabricate and use a motorized hydraulic jack as an inbuilt solution for lifting the vehicle with control in the hand of driver sitting inside. But due to short time span for submitting and syllabus with other core subjects of the term. The idea of fitting and making it slide on the frame was dropped. And finally I submitted the project with objective of designing and fabricating a 12 volt dc hydraulic jack with 1 ton capacity for lifting light motor vehicles. After so many hurdles, this hydraulic jack project was completed some days before the submission date with some fault and must needed corrections, which I did at last moment before submitting. But the idea was great of designing a mechanism which will slide the actuator below the vehicle for lifting desired side. This can reduce all efforts of workmen with only some control switches on dashboard inside the vehicle. Unfortunately due to limited time the objective was altered.
Hydraulics is the branch of fluid mechanics which deals with energy transformation through fluid medium. In this project, fluid is used as a medium for energy transfer. Yes, it is transfer of energy, the electrical energy from the vehicle battery is converted into mechanical energy as linear actuation with the help of a fluid medium.
Major components of the jack
- Hydraulic pump
- Control Unit
- Actuator/Ram Cyclinder
Following points are considered while implementing this hydraulic jack project idea.
- Actuation speed on load should be optimum (Not too slow or fast).
- Load capacity should be enough to lift a car from either side.
- Maximum lifting height should be sufficient for down side inspection.
- Load should remain in standstill position unless dropped by the operator through control unit shutoff function.
The maximum lifting height depends on the actuator stroke while standstill lock is the function of control unit which restricts the reverse flow of fluid from actuator to pump while ram is carrying the load. These both are fabricated according to the design. Actuation speed and load capacity depends upon the combine function of pump, actuator and DC motor. It is quite difficult for an engineering student to make a pump and motor of own choice. So these two components are sourced from scratch. In scratch there are very few chances to get a component fully confirming the specifications with your design. Finally found a smallest pump and a motor in the scratch for the project. Although the components are smallest in the scratch but big for the project. There was no other option available at the time. So I did some alteration in actuator according to the pump and motor. For adjusting the flow rate, pump rpm has been reduced with proper gear ratio between shaft of motor and pump. Control unit is designed with the overload relief, bypass and shutoff functions. As I dropped the initial idea of sliding the actuator on the frame with flexible fluid hose, with remaining setup fitted elsewhere. So all these components, expect the portable actuator, are mounted on aluminum plate with a fluid reservoir, electronic switch and wiring. The actuator is connected to control unit with a flexible high pressure hose.
How it works…
On switching the jack on the motor getting power from battery starts rotating the pump. Pump takes in oil from the reservoir and feed it to the control unit. Control unit redirect the flow towards the actuator and actuator starts lifting the load. On after having full stroke, the relief function reliefs the pressure so thus pump and motor unloaded. The reverse flow of fluid from the cylinder is restricted by the bypass valve or delivery valve fitted inside the control unit. Now the load is up and standstill. While dropping the jack, shut-off valve is opened which releases the fluid from actuator and direct it towards the reservoir and since the load is dropped slowly.
Other Supporting Pictures….