Table Height Adjustment Mechanism

grabcad

My Design of work bench consists of two mechanisms. One is Cross linkage mechanism which is inspired from scissor lift. In scissor lift hydraulic, pneumatic or electrical power may be used, but in my design considering the requirement of adjusting the height manually, I eliminated the usage of any external energy sources and used Screw Jack to have the required motion. I also eliminated the usage of heavy and costly gears and gearboxes which makes the concept very economical. The concept is econimical but still the strength of the design is not compromised. I did the structural analysis using SolidWorks Simulation software to make sure the strength of the design. The factor of safety has arrived 1.2 for the given working load of 500kgs. So, please consider my design for 'Table height adjustment mechanism challenge'.