Scissor Jack

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As long as one has a car, then having this sort of scissor jack in their trunk is practically unavoidable. Used to lift heavy loads, scissor jacks are synonymous with their relative ease of use and their manifest advantage over other mechanical devices used to augment or transport loads. Powered by the rotary motion of the power screw, most scissor jacks can easily lift a 15 kN load with approximately only a 400 N force applied at the crank end. These sorts of numbers imply a large mechanical advantage ratio, which is to be expected in such a device. As the power screw turns, the rotary motion is converted into linear motion in the jack's head. This particular design features a threaded power screw with a pitch of 2.5 mm and 11 mm nominal diameter. The chosen thread type was selected for maximum power transmission capability. The maximum load to be carried under safety conditions was designed to be 800 kg, which is sufficient for the applications this device is commonly used for. Below is the CAD model of the proposed device. All parts were modeled and designed to scale, and an illustrative exploded pictorial view showcasing all the parts that make up the device has been added for clarity. Since aesthetics are an important part in the design process, it was deemed necessary by the designer to add variant colors that potential customers can buy in the event of the contraption being produced. As always, your constructive comments and criticism are always appreciated. If any of you have questions or future design suggestions pertaining to the project, please post them in the comments section below. The CAD files are available for free download on my GrabCAD page: If you're a professional engineer or manufacturer, please contact me for any technical details (detailed drawings, bill of materials, CAD simulation) not mentioned in this post.