Scissor Lifting Mechanism - Essay Example

Scissor Lifting Mechanism College: Testing Scissor Lifting Mechanism After assembly of the scissor lift, the designequipment was subjected to testing. The major tests were the determination of the weight of the equipment as well as the maximum lifting force developed by the scissors lifting and also testing the functionality of the equipment. Materials required for testing The main materials required for testing the equipment were. Weighing machine or a load cell Weights of different sizes. (100g, 250g, 500g and 1kg and 2kg) Tape measure and steel rule. Safety rules observed during experimentation. Some of the safety rules that were observed during the testing of the siccor lift were as follows. The machine was placed in a clear open position and it was ensured that no obstacle was on top of the machine. All the people were advised not to put their arms, hands and feet under the platform when the lift was in motion. Care was taken not to exceed the load capacity of the lift. The machine was placed on a hard, rigid ground which was smooth. This was because the equipment should not be tested or used on uneven, unstable or soft surfaces. Some of the tests done on this prototype were; Testing the operation of the scissor lift system. Measuring the physical dimension of the scissor lift Measuring the weight of the machine Measuring the load bearing capacity or the load carrying capacity of the lift system. All the tests were scheduled to take two hours. The tests were carried out within the stipulated time and the results taken. The operation of the scissor lift The developed scissor lift was tested to determine its workability, functionality and ease of operation. The operator placed the lift on a stable ground and tried if it could be raised and lowered using the rubber bands. On testing the system, it was found to rise through a distance of one meter. The system was able to rise with ease and no difficulties such as lift jamming were experienced (Sigir, 2009). Size and weight requirement The developed prototype was tested to check if it was within the design specification. The whole scissor lift was mounted on a load cell and its total weight determined. The weight of the equipment was found to be less than four (4) Kg as set in the design parameters and specifications. The size of the equipment was also determined by measuring the maximum length and width of the lift as well as the minimum length. Maximum lifting force To determine the actual weight that can be lifted without damaging the equipment. The weights were added in sequence starting with the 100g weight, 500g weight, 750g and finally the 1000g weight. To increase the efficiency of the lift system and the input force, allowance for additional rubber bands was provided. After testing it was found that the scissor lift was able to raise 1 Kg. This was in agreement with the design specifications. Case study of the scissor lifts mechanism On of the patent for the scissor lift mechanism is the Drum Lifters/ Dumpers, the patent number is 7213686, the inventor of this lifting mechanism is Kaufman Michael and the product filing date was March 2004. The scissor lift mechanism has at least two scissor elements. These elements are connected by a swivel axis. The device has a drive for raising and lowering the scissor elements. The scissor mechanism has two coupling bridges that aid in the reduction of traction power and at the same time reduces the control complexity. These bridges are situated at the opposite sides of the coupling and are supported by thrust struts located at the each of the two scissor elements. The distance between the coupling bridges and the height of lift are easily varied. The variation is done by application of a traction force (Kaufman, 2009). Some of the major patent details for this patent are; A Scissors lift mechanism where the swivel axis and the coupling bridges are arranged in a common plane. The common plane is horizontal The traction member is guided back and forth through a plurality of general paths that are between the coupling bridges. The parallel paths of traction are arranged on top of each other. There is an equal spacing between the coupling bridges and the respective scissor elements where the struts are attached. The coupling bridges are arranged and interconnected by a guiding element that can be adjusted. The guide element is made in such a manner that it act as a damping element as well as an emergency brake. The scissor lift mechanism drive is connected to a winding drum of the traction member. The diameter of the drum is a function of the thickness of the traction member and a constant rotational speed of the winding leads to a constant large change in the lift mechanism (Kaufman, 2009). The main aspects of this invention are; Improved scissor type lift mechanism The driving power is reduced bringing about ergonomics aspects of the design The design reduces the complexity making the device suitable for many applications. The main disadvantage of the scissor lift mechanism is the height of the lift that is varied by an expansion in the body. This makes the lever resting position vary greatly against the raised conditions (Kaufman, 2009). The device complies with the Austrian safety standards for lifting devices such as the ergonomics aspects have been considered. Safety, comfortability and ease of torque application have been considered during the design process. Also, the lift system is made in such a way that it cannot tip or overturn; the equipment should also not entrap the parts of the human body, cause injury or fail during operation. This is as stipulated by the Austrian safety standards (Western Australian Consolidated Regulations, 2009). References Sigir. 2009. Helpful Information about Scissor Lifts. [Online]. Available at http://www.sigir08.org/?p=35 .Accessed 30 October 2009. Handle. IT. 2009. Double Scissor Lift Manual. Operation and maintenance manual for double Scissor lifts. [Online]. Available at: http://www.handleitinc.com/literature/manuals/double_scissor_lift_manual.pdf. Accessed 30 October 2009. Think-Greek. 2009. Wooden Hydraulic Machines Kit Set. [Online]. Available at http://www.thinkgeek.com/geektoys/science/bcd8/. Accessed 30th October 2009. Kaufman, M.2009. Scissor Lift Mechanism: Free Patents Online All the Inventions Of Mankind. [Online], Available at: http://www.freepatentsonline.com/7213686.html .Accessed 30 October 2009. Spacepac Industries. 2009. What To Consider When Buying a Scissor Lift Table. [Online]. Available at: http://www.hotfrog.com.au/Companies/Spacepac-Industries/What-to-Consider-When-Buying-a-Scissor-Lift-Tables-10921. Accessed 30 October 2009 Western Australian Consolidated Regulations. 2009. OCCUPATIONAL SAFETY AND HEALTH REGULATION 1996. [Online]. Available at http://www.austlii.edu.au/au/legis/wa/consol_reg/osahr1996382/ Accessed 29 October 2009 Read More