Authors: Vishnu Aadithyan. M, Sabaresan K.S, Sanjith Karthi. R, Dr. D. Shanmugam , Mr. Mahendran
DOI Link: https://doi.org/10.22214/ijraset.2023.51638
Certificate: View Certificate
With the increasing levels of technology, the efforts being put to produce any kind of work has been continuously decreasing. The efforts required in achieving the desired output can be effectively and economically be decreased by the implementation of better designs. Power screws are used to convert rotary motion into translatory motion. A screw jack is an example of a power screw in which a small force applied in a horizontal plane is used to raise or lower a large load. The principle on which it works is similar to that of an inclined plane. The mechanical advantage of a screw jack is the ratio of the load applied to the effort applied. The screw jack is operated by turning a lead screw. The height of the jack is adjusted by turning a lead screw and this adjustment can be done either manually or by integrating an electric motor. In this project, an electric motor will be integrated with the screw jack and the electricity needed for the operation will be taken from the battery of the vehicle and thereby the mechanical advantage will be increased.
I. LITERATURE SURVEY
Screw type mechanical jacks were very common for jeeps and trucks of World War II vintage.
For example, the World War II jeeps (Willys MB and Ford GPW) were issued the "Jack, Automobile, Screw type, Capacity 1 1/2 ton", Ordnance part number 41-J-66. This jacks, and similar jacks for trucks, were activated by using the lug wrench as a handle for the jack's ratchet action to of the jack. The 41-J-66 jack was carried in the jeep's tool compartment. Screw type jack's continued in use for small capacity requirements due to low cost of production raise or lower it. A control tab is marked up/down and its position determines the direction of movement and almost no maintenance.
The virtues of using a screw as a machine, essentially an inclined plane wound round a cylinder, was first demonstrated by Archimedes in 200BC with his device used for pumping water.
There is evidence of the use of screws in the Ancient Roman world but it was the great Leonardo da Vinci, in the late 1400s, who first demonstrated the use of a screw jack for lifting loads. Leonardo?s design used a threaded worm gear, supported on bearings, that rotated by the turning of a worm shaft to drive a lifting screw to move the load - instantly recognisable as the principle we use today.
We can?t be sure of the intended application of his invention, but it seems to have been relegated to the history books, along with the helicopter and tank, for almost four centuries. It is not until the late 1800s that we have evidence of the product being developed further.
With the industrial revolution of the late 18th and 19th centuries came the first use of screws in machine tools, via English inventors such as John Wilkinson and Henry Maudsley The most notable inventor in mechanical engineering from the early 1800s was undoubtedly the mechanical genius Joseph Whitworth, who recognised the need for precision had become as important in industry as the provision of power.
While he would eventually have over 50 British patents with titles ranging from knitting machines to rifles, it was Whitworth?s work on screw cutting machines, accurate measuring instruments and standards covering the angle and pitch of screw threads that would most influence our industry today.
Whitworth?s tools had become internationally famous for their precision and quality and dominated the market from the 18η0s. Inspired young engineers began to put Whitworth?s machine tools to new uses. During the early 1880s in Coaticook, a small town near Quebec, a 24year-old inventor named Frank Henry Sleeper designed a lifting jack. Like da Vinci?s jack, it was a technological innovation because it was based on the principle of the ball bearing for supporting a load and transferred rotary motion, through gearing and a screw, into linear motion for moving the load. The device was efficient, reliable and easy to operate. It was used in the construction of bridges, but mostly by the railroad industry, where it was able to lift locomotives and railway cars.
Local Coati cook industrialist, Arthur Osmore Norton, spotted the potential for Sleeper?s design and in 188θ hired the young man and purchased the patent. The „Norton? jack was born. Over the coming years the famous „Norton? jacks were manufactured at plants in Boston, Coaticook and Moline, Illinois.
Meanwhile, in Alleghany County near Pittsburgh in 1883, an enterprising Mississippi river boat captain named Josiah Barrett had an idea for a ratchet jack that would pull barges together to form a „tow?. The idea was based on the familiar lever and fulcrum principle and he needed someone to manufacture it. That person was Samuel Duff, proprietor of a local machine shop.
Together, they created the Duff Manufacturing Company, which by 1890 had developed new applications for the original „Barrett Jack? and extended the product line to seven models in varying capacities.
Over the next 30 years the Duff Manufacturing Company became the largest manufacturer of lifting jacks in the world, developing many new types of jack for various applications including its own version of the ball bearing screw jack. It was only natural that in 1928, The Duff Manufacturing Company Inc. merged with A.O. Norton to create the Duff-Norton Manufacturing Company.
Both companies had offered manually operated screw jacks but the first new product manufactured under the joint venture was the air motor-operated power jack that appeared in 1929. With the aid of the relatively new portable compressor technology, users now could move and position loads without manual effort. The jack, used predominantly in the railway industry, incorporated an air motor manufactured by The Chicago Pneumatic Tool Company.
Since then the product has evolved to push, pull, lift, lower and position loads of anything from a few kilos to hundreds of tonnes. One of the biggest single screw jacks made to date is a special Power Jacks E-Series unit that is rated for 350 tonnes –even in earthquake conditions for the nuclear industry. More recent developments have concentrated on improved efficiency and durability, resulting in changes in both lead screw and gearbox design options for screw jacks.
A screw jack that has a built-in motor is now referred to as a linear actuator but is essentially still a screw jack. Today, screw jacks can be linked mechanically or electronically and with the advances in motion-control, loads can be positioned to within microns. Improvements in gear technology together with the addition of precision ball screws and roller screws mean the applications for screw jacks today are endless and a real alternative to hydraulics in terms of duty cycles and speed at a time when industry demands cleaner, quieter and more reliable solutions.
II. POWER SCREWS
A power screw is a mechanical device used for converting rotary motion into linear motion and transmitting power. A power screw is also called translation screw. It uses helical translatory motion of the screw thread in transmitting power rather than clamping the machine components.
The main applications of power screws are as follows:
There are three essential parts of a power screw, viz.screw, nut and a part to hold either the screw or the nut in its place. Depending upon the holding arrangement, power screws operate in two different ways. In some cases, the screw rotates in its bearing, while the nut has axial motion. The lead screw of the lathe is an example of this category. In other applications, the nut is kept stationary and the screw moves in axial direction. Screw-jack and machine vice are the examples of this category.
Power screws offer the following advantages:
The disadvantages of power screws are as follows:
D. Forms of Threads
There are two popular types of threads used for power screws viz. square and I.S.O metric trapezoidal.
The advantages of square threads over trapezoidal threads are as follows:
a. The efficiency of square threads is more than that of trapezoidal threads.
b. There is no radial pressure on the nut. Since there is no side thrust, the motion of the nut is uniform. The life of the nut is also increased.
2. Advantages of Trapezoidal Threads
The advantages of trapezoidal threads over square threads are as follows:
a. Trapezoidal threads are manufactured on thread milling machine. It employs multi-point cutting tool. Machining with multi-point cutting tool is an economic operation compared to machining with single point-cutting tool. Therefore, trapezoidal threads are economical to manufacture.
b. Trapezoidal thread has more thickness at core diameter than that of square thread.Therfore; a screw with trapezoidal threads is stronger than equivalent screw with square threads. Such a screw has large load carrying capacity.
c. The axial wear on the surface of the trapezoidal threads can be compensated by means of a split-type of nut. The nut is cut into two parts along the diameter. As wear progresses, the looseness is prevented by tightening the two halves of the nut together, the split-type nut can be used only for trapezoidal threads. It is used in lead-screw of lathe to compensate wear at periodic intervals by tightening the two halves.
III. MECHANICAL JACKS
A mechanical jack is a device which lifts heavy equipment. The most common form is a car jack, floor jack or garage jack which lifts vehicles so that maintenance can be performed. Car jacks usually use mechanical advantage to allow a human to lift a vehicle by manual force alone. More powerful jacks use hydraulic power to provide more lift over greater distances. Mechanical jacks are usually rated for maximum lifting capacity. There are two types of mechanical jacks:
A. Scissor Jacks
A scissor jack has four main pieces of metal and two base ends. The four metal pieces are all connected at the corners with a bolt that allows the corners to swivel. A screw thread runs across this assembly and through the corners. As the screw thread is turned, the jack arms travel across it and collapse or come together, forming a straight line when closed. Then, moving back the other way, they raise and come together. When opened, the four metal arms contract together, coming together at the middle, raising the jack. When closed, the arms spread back apart and the jack closes or flattens out again.
C. Design and Lift
A scissor jack uses a simple theory of gears to get its power. As the screw section is turned, two ends of the jack move closer together. Because the gears of the screw are pushing up the arms, the amount of force being applied is multiplied. It takes a very small amount of force to turn the crank handle, yet that action causes the brace arms to slide across and together. As this happens the arms extend upward. The car's gravitational weight is not enough to prevent the jack from opening or to stop the screw from turning, since it is not applying force directly to it. If you were to put pressure directly on the crank, or lean your weight against the crank, the person would not be able to turn it, even though your weight is a small percentage of the cars.
Screw Jacks are the ideal product to push, pull, lift, lower and position loads of anything from a couple of kilograms to hundreds of tonnes.The need has long existed for an improved portable jack for automotive vehicles. It is highly desirable that a jack become available that can be operated alternatively from inside the vehicle or from a location of safety off the road on which the vehicle is located. Such a jack should desirably be light enough and be compact enough so that it can be stored in an automobile trunk, can be lifted up and carried by most adults to its position of use, and yet be capable of lifting a wheel of a 4,000-5,000 pound vehicle off the ground. Further, it should be stable and easily controllable by a switch so that jacking can be done from a position of safety. It should be easily movable either to a position underneath the axle of the vehicle or some other reinforced support surface designed to be engaged by a jack. Thus, the product has been developed considering all the above requirements. This particular design of the motorized screw jack will prove to be beneficial in lifting and lowering of load
 Design of machine elements by V.B.Bhandari  A text book of machine design by Rajendra Karwa  Analysis and Design of Machine Elements by V K Jadon, Suresh Verma  Tribology in Machine Design by T. A. Stolarski  A text book of Machine Design by R.S.Khurmi,J.K.Gupta  Design of Machine Elements by Farazdak Haideri  Machine Design by S.G.Kulkarni  Design of machine elements by K.Rao  http://en.wikipedia.org/wiki/Jack_(device)  http://hubpages.com/hub/Automobile-Jacks  http://www.powerjacks-de.com/Screw-Jacks-FAQ.html  http://www.radicon.com/screw-jacks.php  http://www.powerjacks.com/PowerJacks-History-The-Screw-Jack-Story.php  http://www.scribd.com/doc/38577261/Screw-Jack-Design
Copyright © 2023 Vishnu Aadithyan. M, Sabaresan K.S, Sanjith Karthi. R, Dr. D. Shanmugam , Mr. Mahendran . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Paper Id : IJRASET51638
Publish Date : 2023-05-05
ISSN : 2321-9653
Publisher Name : IJRASET
DOI Link : Click Here