1PROJECT REPORT ONA JACK CARSubmitted in partial fulfillment of therequirements for the award of the degreeofBACHELOR OF TECHNOLOGYinMECHANICAL ENGINEERINGSubmitted bySAURAV BISWAS 2001413SACHIN GOYAL 2001404ROHIT SINGH KARKI 2001401NISHANT MISHRA 2001368Under the guidance ofMr. GAGAN BANSALAssistant Prof. (ME Dept.)DEPARTMENT OF MECHANICAL ENGINEERINGGRAPHIC ERA UNIVERSITY, DEHRADUNMAY, 2013
2DEPARTMENT OF MECHANICAL ENGINEERINGCANDIDATES’ DECLARATIONI do hereby declare that the work which is being presented in this report entitled “A JACKCAR” submitted towards the partial fulfillment of the requirements for the award of thedegree of Bachelor of Technology in MECHANICAL ENGINEERING from Graphic EraUniversity, Dehradun is an authentic record of my own work carried out under thesupervision of Mr. GAGAN BANSAL, Assistant Professor, Department ofMECHANICAL ENGINEERING.Place: Dehradun Saurav BiswasDate: Sachin GoyalRohit Singh KarkiNishant MishraCERTIFICATEThis is to certify that the above statement made by the candidates is correct to the best of myknowledge.Date:GAGAN BANSALSignature
3DEPARTMENT OF MECHANICAL ENGINEERINGCERTIFICATEThis is to certify that the report entitledA JACK CARSubmitted By-SAURAV BISWAS 2001413SACHIN GOYAL 2001404ROHIT SINGH KARKI 2001401NISHANT MISHRA 2001368may be accepted for the partial fulfilment for award ofBachelor of Technology in MECHANICAL ENGINEERING.Mr. ASHWINI KUMAR Mr. GAGAN BANSAL Mr. AMIR SHAIKHProject Co-ordinator Project Guide Head of theDepartment
4ACKNOWLEDGEMENTApart from our efforts, the success of any project depends largely on the encouragement andguidelines of many others. We take this opportunity to express our gratitude to the peoplewho have been instrumental in the successful completion of this project.We would like to show our greatest appreciation to Mr. GAGAN BANSAL, and Mr.ASHWINI Assistant Professor, Department of Mechanical Engineering, Graphic EraUniversity, Dehradun. We can’t say thank you enough for his tremendous support and help.Without his encouragement and guidance this project would not have materialized.We express a deep sense of gratitude to Mr. AMIR SHAIKH, Head of the Department ofMechanical Engineering, for providing an inspiration required for taking the project to itscompletion.We take this opportunity to thank our Honorable Chairman sir , Mr. KAMALGHANSHALA, for providing healthy environment in our college, which helped inconcentrating on the task.We are also thankful to all the staff members, teaching and non-teaching for helping usduring this project. The guidance and support received from all the members who contributedand who are contributing to this project, was vital for the success of the project. We aregrateful for their constant support and help.SAURAV BISWASSACHIN GOYALROHIT SINGH KARKINISHANT MISHRA
5CONTENTSTitle Page i.Candidates’ Declaration ii.Certificate iii.Acknowledgement iv.Contents v.List of Figures vi.List of Symbols vii.Abstract viii.CHAPTER 1: INTRODUCTION 11.1 Project Motivation 41.2 Back Ground 51.3 Problem Statement 71.4 Objective 81.5Scope 8CHAPTER 2: LITERATURE REVIEW 92.2 Introduction 92.2 Terminology 92.3 Types of Car Jack 162.4 Screw Jack 182.5 Bevel Gear 272.6 Low Speed Geared DC Motor 272.7 Factors Determining The Choice Of Material 28CHAPTER 3: CONSTRUCTION 313.1 Construction Phase 323.2 Lead Screw 333.3 Chassis 373.4 Specifications of Bevel Gear 383.5 Specifications of Dc Geared Motor 393.6 Switch 403.7 Cables 403.8 Battery 413.9 Prototype Model 42CHAPTER 4:MERITS , DEMERITS & APPLICATIONS 444.1 Merits 444.2 Demerits 454.3 Applications 45CHAPTER 5: FUTURE ASPECTS 46CHAPTER 6: CONCLUSION 47REFRENCES 48
6ABSTRACTNow-A-Days, everybody is aware of the several complications and anomaliesthat may or may not occur in a simple LMV. These complications includeunanticipated breakdown, flat tire, etc. or any such complication that renders thevehicle to a halt and unusable. A crude solution for such complications that hasbeen implemented since a long time is a manually operated jack. Hence,irrespective of its size and weight a jack that is used to lift the vehicle is one ofthe most essential accessories that need to be constantly kept close at hand.Thus, the need of keeping the jack available is undeniable. These days severaltypes of either manually operated or automatic jacks whetherlightweight/portable or heavy are widely used to fulfill their purposes in liftingheavy as well as light equipments. There are only a few types of jacks that areconsistently used for lifting a vehicle during its repair work or any such purposeviz. manually operated screw jacks, manually operated screw jacks, manuallyoperated hydraulic jacks etc. Even though they fulfill their purpose there is ahuge drawback to these kinds of jack i.e. they are manually operated andconsume a substantial amount of time and energy for their operation. Thus analternative for these jacks which is already integrated and automatic wouldprove to be beneficial to the end user as well as the repairmen. One suchalternative is the Integrated Automated Screw Jack. This jack would bepermanently mounted on the chassis on the vehicle and will be automaticallyoperated which will evidently eliminate manually operating it to raise thevehicle and would save valuable time.
7LIST OF FIGURESFIGURE No. TITLE OF FIGURE PAGE No.2.1 Screw jack 102.2 Pahl & Beitz Model of Design Process 142.3 A Car 152.4 House Jack 162.5 Graph b/w efficiency & Helix angle 212.6 Bevel Gear 272.7 Geared Motor 273.1 Prototype Mechanism 313.2 Lead Screw 333.3 Pitch Count 333.4 Major Diameter 343.5 Minor Diameter 353.6 Pitch Diameter 363.7 Types of Thread starts 363.8 Prototype Chassis 373.9 Bevel Gear Arrangement 383.10 Low Speed Geared DC Motor 393.11 Toggle Switch 403.12 Control Cables 403.13 12 V Car Battery 413.14 Lifted Front view of Prototype 423.15 Side View of Prototype 423.16 lift Provided by Prototype 433.17 Normal Stationary Position & Ground Clearance 43.
8LIST OF SYMBOLSη Efficiencyα Helix angleᵠ Angle of frictionμ Coefficient of frictionτ Torque
9CHAPTER 1INTRODUCTION1. INTRODUCTION:Due to the difficulty of operating automobile jacks, various forms of electricjacks have been proffered. With the development of such electric jacks hasgradually come an understanding of some of the problems associated therewith.Due to the torque needed to lift something as heavy as most automobiles, directdrive electric motors are not reliable; therefore, reduction gear drivemechanisms of some sort should be employed, as a severe mechanicaladvantage must be utilized. Direct motor-to-jack drive, with only two gears,fails to accomplish this task. Electric jacks that are built into an automobile havenot been accepted due to expense and the need to at least lift each side of anauto, if not all corners individually. If a system is chosen to individually lifteach corner of the auto, even greater expense in design, production, and cost isencountered. Some have even entertained total encasement of a screw jack typedevice. The invention relates to hydraulic jack and more specifically to anautomobile hydraulic jack system. In most of the garages the vehicles are liftedby using screw jack. This needs high man power and skilled labors In the pastboth hydraulic and pneumatic jack has been utilized in combination with thestructure of automobile. They have always utilized a separate jack for each of 4wheels by having the jacks permanently installed on the vehicle. They are readyto operation at all time. Lifting device has been installed on vehicle, such as airlifting device. Various types of jack or lift devices has been installed on vehiclewhich are turned in 1 fashion or another from a horizontal altitude into a verticalaltitude and then extended for the purpose of lifting the vehicle. It is an object of
10the invention to provide a novel screw jack system that only utilized screwjacks, one that is mounted on chassis on side of car between two wheels and 2jacks that is mounted on side of automobile between its side wheels. It is also anobject of invention to provide novel jack system that can be operated by driverfrom inside the car. It is also an object of invention to. Now the project hasmainly concentrated on this difficulty, and hence such that the vehicles can belifted from the floor land without application of any impact force. By pressing+the button in the dashboard, it activates the screw jack automatically.It is believed that “Necessity is the mother of invention”. Here the necessity liesin reducing the human effort applied during manual operation of the jacks andhence the need of the invention. In day to day life it is very tedious job tooperate the jack manually and it is also a very time consuming work as well. Toreduce the human effort for operating any kind of jack separately. This willmost appropriately benefit senior citizens to provide a safe and simpleautomatic screw jacking system without manual effort. To provide a noveljacking system that can be operated from within the vehicle by means of adashboard control panel. There are certain mechanisms already available for thesame purpose which has a definite capacity to lift the car on 2 wheels viz. ascrew jack, hydraulic jack etc. But the general idea of the project is to minimizethe human effort while operating the jack. To provide a novel screw jackingsystem that is directly and permanently incorporated into the vehicle frame insuch a way as to prevent the additional risk of damage or wear and tear.A primary object of the present invention is to provide a motorized screw jackfor automobiles that can be used during inclement weather. Another object ofthe present invention is to provide a motorized screw jack that is driven by theelectric power source from the 12 volt battery of any automobile. Yet anotherobject of the present invention is to provide a motorized screw jack that a motoris provided for the rotation of a displacement screw, clockwise and counter
11clockwise in order to provide for the raising and lowering of the frame portionof the screw jack. Still yet another object of the present invention is to provide amotorized screw jack for automobiles that provides an upper limit switchpositioned in a sealed housing that as the jack moves in an upward direction adriving element on one portion of the upper structure makes contact with abiased displacement element on the opposing portion of the upper structuredriving a contact of the biased element into a contact of a fixed contact tocomplete the limiting circuit. Another object of the present invention is toprovide a motorized screw jack for automobiles that provides a lower limitswitch that as the jack moves in a downward direction the displacement screwcomes in direct contact with a limit switch roller and drives a contact of a biasdisplacement element into a fixed contact to complete the limiting circuit. Anobject of the electric screw jack apparatus is to use electrical power alreadyavailable to elevate an automobile. Another object of the electric screw jackapparatus is to incorporate a screw jack in electrically elevating an automobile.An added object of the electric screw jack apparatus is to employ gear reductiondrive between the motor and the screw jack. A further object of the electricscrew jack apparatus is to ensure a fail-safe coupling between the gear reductiondrive and the screw jack. And, an object of the electric screw jack apparatus isto gain electrical power from the battery from an automobile. Yet another objectof the electric screw jack apparatus is to provide for an inexpensive multiplejack size utilization with a motor and gear reduction member change. A furtherobject of the electric screw jack apparatus is to be integrated.Screw jack is one of the most widely used accessories for lifting vehicles andlight or heavy equipments. It is relatively cheaper than its counterparts and mostwidely and readily available. It is made up of High Carbon Steel and otheralloying elements which impart strength and ductility. It is rigid in constructionbut flexible in its pattern of usage. Flexible in a sense that it can used for a
12variety of purposes ranging from lifting of cars to elevating foundations of ahouse for which screw jacks of very high capacity can be used.1.1 PROJECT MOTIVATIONAn automotive jack is a device used to raise all or part of a vehicle into the airin order to facilitate repairs. Most people are familiar with the basic car jack(manually operated) that is still included as standard equipment with most newcars. These days, a car jack is an important tool to have in our vehicle due tounknown upcoming event such as flat tire in our journey. Even so, people wholike to rotate their tires themselves or who may install snow tires before thewinter and remove them in the spring need to use a jack to perform the job.Changing a flat tire is not a very pleasant experience.Women may be able to drive a five-ton truck, but need a mans help if they mustchange a tire. Women have a much lighter skeleton that means, among otherthings, she can’t pull more forces as well as men and are at greater risk ofskeletal injuries.Working near a vehicle that is supported by a car jack can be fatal. In Australia,over the last four years at least 19 people have been crushed and killed by avehicle while they were working. All the deaths were men and involved thevehicle being lifted or supported in the wrong way .On average, 160 injuries areassociated with car jacks each year. Injuries have ranged from amputation tofractures and crush injuries. The correct use of jacks can prevent death orinjury.
13Available car jacks, however, are typically manually operated and thereforerequire substantial laborious physical effort on the part of the user. Such jackspresent difficulties for the elderly and handicapped and are especiallydisadvantageous under adverse weather conditions.In today’s scenario basic problem arises with the families is of unloading theluggage to get the car jack out of the car.1.2 BACKGROUNDIn the repair and maintenance of automobiles (car), it is often necessary to raisean automobile to change a tire or access the underside of the automobile.Accordingly, a variety of car jacks have been developed for lifting anautomobile from a ground surface. Available car jacks, however, are typicallymanually operated and therefore require substantial laborious physical effort onthe part of the user. Such jacks present difficulties for the elderly andhandicapped and are especially disadvantageous under adverse weatherconditions.Furthermore, available jacks are typically large, heavy and also difficult tostore,transport, carry or move into the proper position under an automobile. Inaddition, to the difficulties in assembling and setting up jacks, such jacks aregenerally not adapted to be readily disassembled and stored after automobilerepairs have been completed. Suppose car jacks must be easy to use forpregnant women or whoever had problem with the tire in the middle ofnowhere.In light of such inherent disadvantages, commercial automobile repair andservice stations are commonly equipped with large and hi-tech car lift, whereinsuch lifts are raised and lowered via electrically-powered systems. However,
14due to their shear size and high costs of purchasing and maintaining electrically-powered car lifts, such lifts are not available to the average car owner.Engineering is about making things simpler or improving and effective. Suchelectrical-powered portable jacks not only remove the arduous task of lifting anautomobile via manually-operated jacks, but further decrease the time needed torepair the automobile. Such a feature can be especially advantageous when it isnecessary to repair an automobile on the side of a roadway or under otherhazardous conditions.There also reports on car jacks which lead to a serious number ofaccidents.These are due of safety features that are on conventional car jacks arenot enough. A specified jack purposed to hold up to 1000 kilograms, but testsundertaken by Consumer Affairs has revealed that is fails to work after lifting250 kilograms and may physically break when it has a weight close to its 1000kilograms capacity. Whilst no injuries have been reported to date, Ms Rankinehas expressed concerned about the dangers associated with the use of a vehiclejack that does not carry the weight it is promoted to hold. Tests have proven thatthe jack has the propensity to buckle well under the weight it is promoted towithstand, and it doesn’t meet the labeling or performance requirements of theAustralian Standard for vehicle jacks.
151.3 PROBLEM STATEMENTAvailable jacks present difficulties for the elderly, women and are especiallydisadvantageous under adverse weather conditions. These presently availablejacks further require the operator to remain in prolonged bent or squattingposition to operate the jack.Doing work in a bent or squatting position for a period of time is not ergonomicto human body. It will give back problem in due of time. Moreover, the safetyfeatures are also not enough for operator to operate the present jack. Present carjack do not have a lock or extra beam to withstand the massive load of the car.This is for the safety precaution in case if the screw break.Furthermore, available jacks are typically large, heavy and also difficult tostore, transport, carry or move into the proper position under an automobile.Suppose car jacks must be easy to use for pregnant women or whoever hadproblem with the tire in the middle of nowhere.The purpose of this project is to encounter these problems. An electric –pneumatic car jack system Which would comprise of 4 electro-pneumatic jacksattached with the chassis at the four corners each operating individually wouldbe developed. Operator only needs to press the button from the controllerwithout working in a bent or squatting position
161.4 OBJECTIVESIn order to fulfill the needs of present car jack, some improvement must bemade base on the problems statement: To design and implement a car jack system that is safe, reliable and ableto raise and lower the height level when framed with the chassis of a carindividually at each corners . To develop a car jack system that is powered by internal car power andfully automated working individually with a button system.1.5 SCOPESI. The developed automatic car jack can only withstand belowII. The developed automatic car jack must be operated on a flat surface.III. The developed A jack car is only a prototype and not readily functioningas commercial product.IV. The design is based on current screw jack & cars in the market.V. The developed A jack car is for all individual person.VI. The developed A jack car can only work by using the internal car power(12V)
17CHAPTER 2LITERATURE REVIEW2.1 INTRODUCTIONThe main purpose of this literature review is to get information about the projectfrom the reference books, magazines, journals, technical papers and web sites.In this chapter the discussion will be made base on all the sources.2.2 TERMINOLOGYIn this section, all the terminology on this project is presented.2.2.1 JackA mechanical jack is a device which lifts heavy equipment. The most commonform is a car jack, floor jack or garage jack which lifts vehicles so thatmaintenance canbe performed. Car jacks usually use mechanical advantage to allow a human tolift a vehicle. More powerful jacks use hydraulic power to provide more liftover greater distances. Mechanical jacks are usually rated for a maximum liftingcapacity (for example, 1.5 tons or 3 tons).
18Fig :2.1 Screw jack2.2.2 DesignTo design is either to formulate a plan for the satisfaction of a specified need orto solve a problem. If the plan results in the creation of something having aphysical reality, then the product must be functional, safe, reliable, competitive,usable,manufacturable, and marketable. .
19These terms are defined as follows:I. Functional: The product must perform to fill its intended need andcustomer expectation.II. Safe: The product is not hazardous to the user, bystanders, or surroundingproperty. Hazards that cannot be ‘designed out’ are eliminated byguarding (a protective enclosure); if that is not possible, appropriatedirections or warning are provided.III. Reliable: Reliability is the conditional probability, at a given confidencelevel,that the product will perform its intended function satisfactorily orwithout failure at a given age.IV. Competitive: The product is a contender in its market.V. Usable: The product is ‘user friendly’ accommodating to human size,strength.Posture, reach, force, power and control.VI. Manufacturable: The product has been reduced to a ‘minimum’ numberof parts.Suited to mass production, with dimensions, distortion, andstrength under control.
20VII. Marketable: The product can be bought, and service (repair) is available.It is important that the designer begin by identifying exactly how torecognize a satisfactory alternative, and how to distinguish between twosatisfactory alternatives in order to identify the better. From this,optimization strategies can be formed or selected.Then the following tasks unfold: Invent alternative solution Establish key performance metrics Through analysis and test, simulate and predict the performance of each alternative, retain satisfactory alternatives, and discard unsatisfactoryones. Choose the best satisfactory alternatives discovered as an approximationto optimality. Implement the designThe characterization of a design task as a design problem can introduce the ideathat, as a problem, it has solution. The design of the project is explained asfollows:
21Configuration: Bevel gear arrangment, bearing, housing lead screw (the power screw)Function: Elevating & LoweringPower Source: ElectricallyCharacteristic: Positioning precision, Safely self-locking, Heavy duty, Uniform lifting speed, small sizes, easy installation, low noise, long life, security and environment protection.
220.127.116.11 Flow Chart of Design & optimization ProcessFig : 2.2 Pahl & Beitz Model of design Process
232.2.3 CARAn automobile, autocar, motor car or car is a wheeled motor vehicle usedfor transporting passengers, which also carries its own engine or motor. Mostdefinitions of the term specify that automobiles are designed to run primarily onroads. The term motorcar has also been used in the context of electrified railsystems to denote a car which functions as a small locomotive but also providesspace for passengers and baggage. These locomotive cars were often used onsuburban routes by both interurban and intercity railroad systems. Mostautomobiles in use today are propelled by an internal combustion engine, fueledby deflagration of gasoline (also known as petrol) or diesel. Both fuels areknown to cause air pollution and are also blamed for contributing to climatechange and global warming.FIG 2.3 A Car
242.3 TYPES OF CAR JACK2.3.1 House Jack Or Screw JackA house jack, also called a screw jack is a mechanical device primarily usedto lift buildings from their foundation for repairs or relocation. A series of jacksare used and then wood cribbing temporarily supports the structure. Thisprocess is repeated until the desired height is reached. The house jack can beused for jacking carrying beams that have settled or for installing new structuralbeams. On the top of the jack is a cast iron circular pad that the 4” × 4” post isresting on. This pad moves independently of the house jack so that it does notturn as the acme-threaded rod is turned up with a metal rod. This piece tilts veryslightly but not enough to render the post dangerously out of plumb.Fig 2.4 House jack
252.3.2 Hydraulic jackHydraulic jacks are typically used for shop work, rather than as an emergencyjack to be carried with the vehicle. Use of jacks not designed for a specificvehicle requires more than the usual care in selecting ground conditions, thejacking point on the vehicle, and to ensure stability when the jack is extended.Hydraulic jacks are often used to lift elevators in low and medium risebuildings.A hydraulic jack uses a fluid, which is incompressible, that is forced into acylinder by a pump plunger. Oil is used since it is self lubricating and stable.When the plunger pulls back, it draws oil out of the reservoir through a suctioncheck valve into the pump chamber. When the plunger moves forward, it pushesthe oil through a discharge check valve into the cylinder. The suction valve ballis within the chamber and opens with each draw of the plunger. The dischargevalve ball is outside the chamber and opens when the oil is pushed into thecylinder. At this point the suction ball within the chamber is forced shut and oilpressure builds in the cylinder.In a bottle jack the piston is vertical and directly supports a bearing pad thatcontacts the object being lifted. With a single action piston the lift is somewhatless than twice the collapsed height of the jack, making it suitable only forvehicles with a relatively high clearance. For lifting structures such as housesthe hydraulic interconnection of multiple vertical jacks through valves enablesthe even distribution of forces while enabling close control of the lift.In a floor jack (aka trolley jack) a horizontal piston pushes on the short end ofa bellcrank, with the long arm providing the vertical motion to a lifting pad,kept horizontal with a horizontal linkage. Floor jacks usually include castorsand wheels, allowing compensation for the arc taken by the lifting pad. This
26mechanism provide a low profile when collapsed, for easy maneuveringunderneath the vehicle, while allowing considerable extension.2.3.3 Pneumatic JackA pneumatic jack is a hydraulic jack that is actuated by compressed air - forexample, air from a compressor - instead of human work. This eliminates theneed for the user to actuate the hydraulic mechanism, saving effort andpotentially increasing speed. Sometimes, such jacks are also able to be operatedby the normal hydraulic actuation method, thereby retaining functionality, evenif a source of compressed air is not available.2.4 Screw JackScrew jack is a portable device consisting of a screw mechanism used to raise orlower the load. There are two types of jacks most commonly used,1] Hydraulic2] Mechanical
272.4.1 Merits of Screw jack –1] Can be used to lift a heavy load against gravity.2] Load can be kept in lifted position.3] Due to leverage obtained by handle force required to raise load is very less &can be applied manually also2.4.2 Demerits of screw jack –1] Chances of dropping of load2] Tipping or slipping of load.3] This failure is not “SAFE FAIL”& can cause serious accidents.2.4.3 Reasons of Accidents –1] Load is improperly secured on jack.2] The screw jack is overloaded.3] Center of gravity is off center with axis of jack.4] Jack is not placed on hard & level surface.
282.4.6 Efficiency of screw jackThe efficiency of square threaded screws may be defined as the ratio betweenthe ideal effort (i.e. the effort required to move the load, neglecting friction) tothe actual effort (i.e. the effort required to move the load taking friction intoaccount).We know that the effort applied at the circumference of the screw to lift theload isP = W tan (α + φ) ...(i)where W = Load to be lifted,α = Helix angle,φ = Angle of friction, andμ = Coefficient of friction between the screw and nut = tan φ.If there would have been no friction between the screw and the nut, then φ willbe equal to zero.The value of effort P0 necessary to raise the load, will then be given by theequation,P0 = W tan α [Substituting φ = 0 in equation (i)]This shows that the efficiency of a screw jack, is independent of the loadraised.In the above expression for efficiency, only the screw friction isconsidered.
29Fig : 2.5 Graph b/w Efficiency & Helix Angle2.4.5 Over Hauling and Self Locking ScrewsWe have seen that the effort required at the circumference of the screw to lowerthe load isP = W tan (φ – α)and the torque required to lower the load,In the above expression, if φ < α, then torque required to lower the load will benegative. In other words, the load will start moving downward without the
30application of any torque. Such acondition is known as over hauling of screws.If however, φ > α, the torque required to lower the load will be positive,indicating that an effort is applied to lower the load. Such a screw is known asself locking screw. In other words, a screw will be self locking if the frictionangle is greater than helix angle or coefficient of friction is greater than tangentof helix angle i.e. μ or tan φ > tan α.2.4.6 Efficiency of Self Locking ScrewsWe know that the efficiency of screw,and for self locking screws, φ ≥ α or α ≤ φ.∴ Efficiency for self locking screws,From this expression we see that efficiency of self locking screws is less than ½or 50%. If the efficiency is more than 50%, then the screw is said to beoverhauling.
31Note: It can be proved as follows:Let W = Load to be lifted, andh = Distance through which the load is lifted.∴ Output = W.h2.4.6 Screw jack has following parts :-1] FRAME2] SCREW3] NUT4] HANDLE5] CUP6] SET SCREW7] WASHER
318.104.22.168 FRAME –• FRAME SIZE - Most of the times frame is conical in shape and hollowinternally to accommodate a nut & screw assembly. The hollow conical shapeinsures a safe & complete resting of a jack on ground. If it is provided with legslike structure , it quite possible that in case of uneven distribution load may faildown because all legs will not touch ground.• FORCE ANALYSIS – The force by a load is directed by a cup to screw thenis directed by cup to screw then to threads of screw to nut then to frame so it isalways compressive in nature.• MANUFACTURING PROCESS – The complex shape of frame leads us touse a ’Casting’ process for manufacturing. For all this purpose We need toselect a cast iron as material for frame. We select a FG200 as material for framesuch as it contains carbon precipitates as “graphite flakes” as graphite is soft innature it improves its ability to resist a compressive load.FG200 = Graphite flakes Gray cast iron with ultimate tensile strength of200N/mm22.214.171.124 SCREW –• SCREW SIZE – Screws is nothing but a member having Helical groovearound periphery of solid bar. It can be around 22 to 100mm diameter forsquare power screws & 24 to 100mm for trapezoidal power screws.• THREAD PROFILE – The screw or power screw thread is always a squaretype because it has more efficiency than trapezoidal threads and there is noradial thrust on screw i.e. no Bursting Pressure, so motion is uniform.
33• Square threads usually turned on lathes using single point cutting tool. Itleads us to use free cutting steel.• Square threads are weak in roots. Wear of thread surface lead us to use“Unalloyed free cutting steel”.We select “25C12S14 UNALLOYED FREE CUTTING STEEL”It indicates - 025% carbon, 1.2% manganese, 0.14%sulphurIt has tensile strength of 560N/mm2 with 10% elongation. Sulphur givesresistance to wear & 0.25% carbon gives it sufficient strength to compensateweakness in roots. also easy in cutting due to manganese.126.96.36.199 NUT –• As we know there always a relative motion between screw and nut, whichcause a friction. The friction causes wear if some material is used for screw &nut it will wears both components. So one out of two has to be softer than otherso as to ease of replacement. The size & shape of screw is costlier than nut, sogenerally we use softer material for nut than screw.• Phosphor bronze is ideal material for nut which is a copper alloy having0.2%phospher which increases tensile strength. Ultimate tensile strength for thisis 190mpa and coefficient of friction is 0.1 Bearing pressure is 10mpa.• Advantages of phosphor bronze are,1] Good corrosion resistance.2] Low coefficient of friction3] Higher tensile strength than copper brass.
3188.8.131.52 HANDLE –• Handle is subjected to bending moments.• So plain carbon steel with 0.3%carbon i.e. 30C8 can be selected.• Yield strength in tension is 400mpa184.108.40.206 CUP –• Shape of cup is again complex and so economical to manufacture by Castingprocess, hence material will be cast iron with grade FG220.127.116.11.6 SETSCREW –• Purpose of set screw is to resist motion of nut with screw. 5• It can be of commercial steel.18.104.22.168 WASHER –• Washer is to provide uniform force of tightening nut over screw force byenlarging area under actions of force. We can use commercial steel.
352.5 Bevel GearThe bevel gears are used for transmitting power at a constant velocity ratiobetween two shafts whose axes intersect at a certain angle.Fig: 2.6 Bevel gear2.6 DC Geared MotorFig 2.7 DC geared Motor
362.7 MaterialsMaterials require for the manufacturing of a components depends upon thefollowing factors:FACTORS DETERMINING THE CHOICE OF MATERIALSThe various factors which determine the choice of material are discussedbelow.1. Properties:The material selected must posses the necessary properties for the proposedapplication. The various requirements to be satisfied can be weight, surfacefinish, rigidity, ability to withstand environmental attack from chemicals,service life, reliability etc.The following four types of principle properties of materials decisively affecttheir selectiona. Physicalb. Mechanicalc. From manufacturing point of viewd. ChemicalThe various physical properties concerned are melting point, ThermalConductivity, Specific heat, coefficient of thermal expansion, specific gravity,electrical Conductivity, Magnetic purposes etc.The various Mechanical properties Concerned are strength in tensile,compressive shear, bending, torsional and buckling load, fatigue resistance,impact resistance, elastic limit, endurance limit, and modulus of elasticity,hardness, wear resistance and sliding properties.
37The various properties concerned from the manufacturing point of view are. Castability, Weldability, Brazability, orge ability, erchantability, urface properties, hrinkage, Deep drawing etc.2. Manufacturing Case:Sometimes the demand for lowest possible manufacturing cost or surfacequalities obtainable by the application of suitable coating substances maydemand the use of special materials.3. Quality Required:This generally affects the manufacturing process and ultimately the material.For example, it would never be desirable to go for casting of a less number ofcomponents which can be fabricated much more economically by welding orhand forging the steel.
384. Availability of Material:Some materials may be scarce or in short supply. It then becomes obligatory forthe designer to use some other material which though may not be a perfectsubstitute for the material designed.The delivery of materials and the delivery date of product should also be kept inmind.5. Space Consideration:Sometimes high strength materials have to be selected because the forcesinvolved are high and the space limitations are there..6. Cost:As in any other problem, in selection of material the cost of material plays animportant part and should not be ignored.Some times factors like scrap utilization, appearance, and non-maintenance ofthe designed part are involved in the selection of proper materials.
39CHAPTER 3CONSTRUCTIONWorm and worm gear, bearing, housing and lead screw (the power screw).Here in this project the lead screw is driven by the help of a worm gearassembly which is automated by a help of a 12v dc low speed geared motor, aswe can see in the picture shown below:Fig :3.1 Prototype mechanism
403.1 CONSTRUCTION PHASENow let us discuss the construction phase step by step: First of all the jack with the above said dimensions is coupled with thegeared dc speed motor. Now the motor is connected with a 12v dc supply keeping in mind thepower consumption of the motor the battery or the supply should becapable enough to drive the motor. Now this assembly is fixed with the help of nuts & bolts and weldingprocess as required with the frame of our vehicle. Here in our project wehave fixed the jack only in one place as we are trying to display theconcept so we have not placed the jack in all the four sides of the vehicle. The frame is covered as required at the last, so that the display of theconcept is as same as in actual vehicle. A 2-way switch has been used in order to drive the motorised jack. The construction of our model has been kept as simple as possiblekeeping in mind the abstract of the project and also keeping in mind thecost limitation of the project so as to justify the prototype model conceptand to utilize the maximum resources available to us.
413.2 LEAD SCREWThe lead/ power screws (also known as translation screws) are used to convertrotary motion into translatory motion In case of screw jack, a small forceapplied in the horizontal plane is used to raise or lower a large load.3.2.1Thread Form:The lead screw having Acme threads having 29°thread angle.Fig : 3.2 Lead Screw3.2.2Thread Pitch:The thread pitch is the axial distance from one thread groove to the next-5.0mmFig :3.3 Pitch count
423.2.3 Major Diameter:It is the largest diameter of an external or internal screw thread. The screw isspecified by this diameter. It is also known as outside or nominal diameterThe major diameter can be measured with a micrometer, caliper or steel rule.Major diameters are generally the first numbers found in thread designations-Major Diameter :20mm2022Fig : 3.4 Major Diameter3.2.4 Minor Diameter:It is the smallest diameter of an external or internal screw thread. It is alsoknown as core or root diameter.The minor diameter can be measured with a micrometer, caliper or steel ruleMinor Diameter :17.2mm
43Fig : 3.5 Minor Diameter3.2.5 Pitch DiameterIt is the diameter of an imaginary cylinder, on a cylindrical screw thread,thesurface of which would pass through the thread at such points as to make equalthe width of the thread and the width of the spaces between the threads. It isalso called an effective diameter. In a nut and bolt assembly, it is the diameter atwhich the ridges on the bolt are in complete touch with the ridges of thecorresponding nut.Pitch Diameter:19.5mm
44Fig : 3.6 Pitch Diameter3.2.6 Hand of Thread:The thread is of 1 startFig : 3.7 Types of thread starts
453.3 ChassisThe frame which supports an automobile is called Chassis.The prototype of chassis is made up of cast iron hollow pipe material ofthickness 2mm and cross setion of 2 inch × 1 inch. The total length and widthof this rectangular frame is 3 feet × 2 feet.The shape of the prototype chassis is close to the original chassis.Fig 3.8 Prototype Chassis
463.4 Specifications of Bevel GearThe bevel gear assembly shaped like right circular cone their imaginary verticesmust occupy the same point.Fig : 3.9 Bevel Gear Arrangement Pitch- 5.0mm No of teeth Pinion 10 No. of teeth Gear 21 Major diameter of Pinion : 40 mm Major diameter of gear : 90 mm Minor Diameter of pinion :30 mm Minor Diameter of gear : 80 mm
473.5 Specifications of DC Low Speed Geared Motor Rated Voltage : 12V Rared Speed : 50 RPM( max) Rated Power :0 .15 hp Rated Load : 60 watts Rated Torque : 10 N-m Mounting : M-6 screw holes Shaft : 10mm shaft with 2 flats where flat is 6.6mm & threaded end to fita M-6 tightening nut.-Fig : 3.10 Low Speed Geared DC Motor
483.6 SwitchA switch is used in order to start or stop the entire operation of the screw jack.The type of switch that is used is known as a toggle switch.Fig : 3.11 Toggle Switch3.7 CablesControl cables are used in order to connect the battery to the motor and theswitchFig : 3.12 control cables
493.8 BatteryLead–acid batteries, invented in 1859 by French physicist GastonPlanté, are the oldest type of rechargeable battery. Despite having avery low energy-to-weight ratio and a low energy-to-volume ratio, theirability to supply high surge currents means that the cells maintain arelatively large power-to-weight ratio. These features, along with theirlow cost, make them attractive for use in motor vehicles to provide thehigh current required by automobile starter motors.Fig : 3.13 12 V Car Battery
503.9 Prototype ModelFig 3.14 Lifted Front view of PrototypeFig 3.15 Side view of prototype
51Fig 3.16 lift Provided by PrototpeFig 3.17 Normal Stationary Position & ground Clearance
52CHAPTER 4MERITS, DEMERITS & APPLICATION4.1 MERITS Simpler Design: As all the components are pre-engineered only slightmodification is required Almost zero maintenance Cost of power transmission is minimum as it uses internal car power with12V geared motor Self locking Property of Power Screw reduces chances of accident. Repairing is easy. Replacement is easy Manual Power not required. If in case extra lift is required small manual screw loosening has to bedone. The loaded light vehicles can be lifted easily
534.2 DEMERITSThe possible disadvantages of this invention may be as below, but if comparewith effective it is negligible. Elements of this system have to manufactured separately to a high degreeof precision which increases the overall manufacturing cost of the system. The entire system is subjected to mechanical friction, hence regularlubrication must be provided Intial cost in design modifications Additional protection against rust and corrosion is required.4.3 ApplicationsThe innovation has several advantages and wide scope of applications: It would be useful for car owners for onsite tyre replacement It would be helpful for mechanics for reparing of parts on chassisanywhere by lifting the car on integrated jacks. It can be used in all types of LMV’s & with slight modifications onSUV’s & LUV’s also.
54CHAPTER 5FUTURE ASPECTSFUTURE ASPECTS: This innovation would help the women elders and other fellow folks toeasily change the tires when stuck in the middle of nowhere. This innovation would save time of installing a manual jack andunloading the vehicle as the problem of unloading would be minimized. It would help in washing of the lower body of the car as it would raise thecar by about 2 feet. It would help the mechanic to repair on road as the innovation wouldincrease the road clearance of the car and would be easily repaired. As the innovation is new and never been used anywhere in the world wewould work on this so we could PATENT our innovation. Since a jack has always been an integral part of any operation related toservicing of the vehicle therefore with some substantial modificationslike, by increasing the required torque and power capacity of the jack itcan be used also for HMVs. Some modifications can also be implementedinto the designing of the vehicle chassis to accommodate the jack. Thiswill not only be an efficient design but also be rugged.
55CHAPTER 6CONCLUSIONThe present invention is a vehicle screw jack jack positioned on a each sidebetween the front and rear wheels with an electric dc geared motor drivearrangement for the operation of lifting and descending of the vehicle to itsposition for operation. The jack has gear configured for a low speed ofoperation. Switches and are used to control the direction of movement of thejack. Releasing the switches during operation stops the jack in the presentposition. This invention relates to a jacking arrangement for automobileswhereby a lifting jack is secured on the lower part of the chassis of a vehicle.The jack has a screw jacks configuration with a a low speed geared motor motor.The extension of the jack is limited by a switch handle which is configured forcutting off the current flow as the switch is closed by the action of a powerscrew approximately reaching a maximum extension position. Simultaneously,a switch handle is depressed changing the polarity of the current flow throughthe motor thereby positioning the motor for the retraction of the jack. At theinstant prior to the jack reaching a maximum retracted position, polarity switchhandle is depressed again reversing the polarity of the motor. In-place vehiclejack assemblies of the pivoted lever type configured for being permanentlymounted at the front and rear of the vehicle frame structure are described. Eachof the jack assemblies comprises a unitary device which is independentlyoperable by an electrical motor, and independently selectively controlled at thejack or remotely from the control compartment of the vehicle.
56REFRENCES1. Mickael, Emil “Motor driven scissor jack with limit switches.” U.S PatentNumber 6,695,289 B1, 2004.2. Chang; Shoei D. (Da Li Hsien, TW), Liaw; Huey S. (Da Li Hsien, TW),“Motor driven scissor jack for automobiles,” U.S Patent Number4653727, 1987.3. John Norman (2009), Fire Department Special Operations.4. Rodriguez, Daniel G. "Automatic Jacking System for an AutomotiveVehicle." U.S. Patent Number 6,991,221, 2006.5. Integrated Automated Jacks for 4-wheelers P.S. Rana1, P.H. Belge1, N.A.Nagrare1, C.A. Padwad1, P.R. Daga1, K.B. Deshbhratar1N.K.Mandavgade26. 13 april 2013.7. G.B.S. Narang, “Automobile Engineering”, Khanna Publishers,Delhi,1991, pp 671.8. William H. Crowse, “Automobile Engineering”.9. Mechanisms In Modern Engineering Design Vol. V. Part I.10.Elements Of Workshop Technology – VOL II -S. K. Hajra Choudhury.11.R.S. Khurmi & J.K. Gupta ‘A Textbook Of Machine Design’-XIV Edition3