International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: editor@ijaiem.org Volume 4, Issue 5, May 2015 ISSN 2319 - 4847 PORTABLE EXTENDABLE CHAIR 1 Mr. AKSHAY DIXIT , Mr. SIDDHANT CHAWADE2, Mr. ABHIMANYU KUMAR3 Final year student of Department of Mechanical Engineering, GNIT, Ibrahimpatnam ABSTRACT At present people use ladders and long stools to work on a point which is more than their height. In this case one can easily reach the work point, what if he wanted to move the ladder? For this purpose he has to get down and move his ladder every time which consume more time and even increase work burden. For this purpose therefore we intend to design a chair or a platform which is comfortable to work and can be lifted to a certain point and can be moved in horizontal direction. Basically the Portable Extendable Chair is equipment which is served for lifting vertically upwards, moving in horizontal direction and it can be rotated 360 both in clockwise and anticlockwise directions In the design and fabrication of Portable Extendable Chair the Electro-mechanical actuators are used. The Electro-mechanical actuator consists of motor which can drive both in forward and reverse direction, and a Screw attached to its shaft. A nut is welded along the column which makes the screw to rotate and move both up and down.The Portable Extendable Chair has a platform which is designed to be lifted form low to high level using Electro-mechanical actuators. Similarly another Electro-mechanical is used to give horizontal motion to the platform. At the bottom to this platform there is a flywheel gear which is attached to the motor, this gives a rotation movement to the Portable Extendable Chair. The Platform Designed for lifting purpose is comfortable which will easily bear the load. The specifications of motor and screw electro-mechanical actuator can be decided on the basis of applying load and height which is to be lifted. This Portable Lifting Device is designed so that it occupy less space with high comfort factor when compared to other lifting machineries Keyword: Electro-mechanical actuator, wiper motor, fly wheel gear, Screw 1. INTRODUCTION The Portable Extendable chair is a device which can be lifted both up and down i-e can be moved both in vertical direction and horizontal direction. The main intention of designing this Portable Extendable chair was to give more accuracy and more comfort level to the operator who is working at a height which is more than his own height. In this designing of portable Extendable chair we have not only designed the lifting device but also designed and successfully made a pair of electro mechanical actuator at very low cost. These Electro-Mechanical actuator used for vertical lifting and horizontal movement in the chair and this pair of Electro-Mechanical actuator are designed on considering the factors like the height (the amount of distance which is to be lifted) and other important factor which is to be considered is the load ( the amount of weight which is to be lifted). The eye catching feature of the Portable Extendable chair is that it can be rotated 360 both in clockwise and anticlockwise direction. So this Portable Extendable chair basically provides the operator the flexibility to move easily both in horizontal and vertical direction and simultaneously rotated to work on the side walls. 2. ELECTRO-MECHANICAL ACTUATOR Basically the Electro-Mechanical actuator are similar to the mechanical actuator except that the control knob or handle of mechanical actuator is replaced with an electric motor in Electro-Mechanical actuator. This rotary motion supplied by motor (here wiper motor of automobile i-e Car) is used source which provides rotational movement This rotary motion of motor is converted into linear displacement. Here the mechanical actuator functions by converting rotary motion into linear motion to execute movement. As already mentioned that two Electro-Mechanical actuators are used in this project which are responsible for the vertical and horizontal motion. 3. VERTICAL LIFITNG At the base of the Portable Extendable chair an Electro-Mechanical actuator is arranged which is responsible for lifting the operator to the desired height .The base of the Portable Extendable chair is made quiet heavy when compared to the platform at the top this base provides the counter weight when the operator is at the corner. Volume 4, Issue 5, May 2015 Page 456 International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: editor@ijaiem.org Volume 4, Issue 5, May 2015 ISSN 2319 - 4847 Fig 3.1: (a) Assembly (b) Design These above shown are the assembly of actuator and design of the Electro-Mechanical actuator which are used in this project. A hollow cylinder is constructed around the EN8 screw which act as cover and inside a nut is being welded to the cylinder and extended stoke is attached using a bush and a guiding pin is provided so as to guide the lifting. 4. HORIZONTAL MOVEMENT To the top of Portable extendable chair there is a rectangular frame in which there is another actuator arranged which provides horizontal motion to the platform. At one corner of the platform a wiper motor is fixed and an EN8 screw is fixed to the shaft of the motor. A nut is being weld at bottom of the platform. When the motor supplies the rotary motion to the screw, the fixed screw starts rotating and the nut which is welded to the bottom of the platform moves along the rectangular frame, by creating this movement of platform along the rectangular frame horizontal motion to the Portable Extendable chair is achieved. Fig 4.1: (a) Assembly (b) Design 5. WIPER MOTOR The wiper motor is responsible for all the vertical lifting movement, horizontal movement as well as the rotational movement. The motor is used for the rotary feed which later converts into linear displacement.This motor employed in Portable Extendable chair is the wiper motor which are used in automobile i-e in cars, lorry, buses etc. This Wiper motor converts electricity into mechanical work. In the design and manufacturing of Portable Extendable chair the motor for rotary input is Tata Indica’s wiper motor. There are three wiper motors used in manufacturing of Portable Extendable chair the first motor is arranged at the bottom of the base which is responsible for vertical lifting, the other motor is attached to the rectangular frame which gives horizontal motion to the platform and the third motor is Volume 4, Issue 5, May 2015 Page 457 International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: editor@ijaiem.org Volume 4, Issue 5, May 2015 ISSN 2319 - 4847 responsible for rotation of Portable Extendable chair this rotation is obtained by fixing Fly wheel gear and the pinion to the shaft of the motor. 5.1 SPECIFICATIONS Voltage : 12V Power : 50W No load speed : 45-60RPM Full load speed : 40-60RPM Weight : 1.3KG Fig 5.1: Wiper motor used for horizontal vertical and rotatory motion 6. FLY WHEEL GEAR OF SELF START MOTOR A Fly wheel gear of self-start motor of a car is used along with a pinion gear for the rotatory motions. This rotations can be 360 either in clockwise direction or anticlockwise directions. The pinion gear is fixed to the shaft of the motor, it meshes with the fly wheel gear. The pinion gear is connected to the shaft of the wiper motor. As the pinion gear rotates the gear rotates and thus gives a rotary movement to the Portable Extendable chair. The fly wheel gear is fixed to the rectangular frame with a ball bearing inside it. The purpose of bearing is used to reduce rotational friction and support radial and axial loads. Number of teeth of gear = 100 Number of teeth of pinion = 8 Volume 4, Issue 5, May 2015 Page 458 International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: editor@ijaiem.org Volume 4, Issue 5, May 2015 Fig 6.1: (a) Fly wheel gear ISSN 2319 - 4847 (b) Design 7. SCREW A screw with large number of threads is attached to the shaft of the wiper motor. The screw is housed by a hollow cylindrical tube made up of mild steel. Another hollow cylinder is welded to the nut and mounted over the screw. The inner hollow cylinder cannot rotate as it is fixed with the help pf a guiding pin, but it can move vertically upwared and downwards when the motor is turned on. The screw is made up of EN8 steel.EN8 is a grade of steel that is commonly used in shafts, stressed pins and studs. It is a medium-strength steel that is unalloyed and has good tensile strength. EN8 is superior to mild steel in strength, wear resistance and toughness. These properties make EN8 the preferred choice for tasks that cannot be completed using mild steel yet do not justify incurring the additional cost of using an alloyed steel. It is commonly used in engineering applications where parts are not subjected to heavy stress. EN8 is readily machinable and can be welded. It is usually delivered in untreated condition. Fig 7: (a) EN8 screw (b) Design 8. AC TO DC CONVERTER As wiper motors are used which requires DC current from a battery, an AC to DC converter is used. All the motors and switches are connected to the converter. Fig 7.1: AC to DC converter Volume 4, Issue 5, May 2015 Page 459 International Journal of Application or Innovation in Engineering & Management (IJAIEM) Web Site: www.ijaiem.org Email: editor@ijaiem.org Volume 4, Issue 5, May 2015 ISSN 2319 - 4847 9. CONCLUSION The below images are final assembly view and the design view of the Portable Extendable chair.In short this chair is compact and quick to be lifted and can be moved in horizontal direction and easily rotated both in clockwise and anticlockwise direction, this chair consists of rollers which help for shifting this lifitng device to desired location. Fig 9.1 (a): Final prototype (b): Design REFERENCES [1] http://en.wikipedia.org/wiki/Actuator [2] http://en.wikipedia.org/wiki/Linear_actuator [3] http://www.weiku.com/products/5738035/AC_TO_DC_power_converter.html [4] http://en.wikipedia.org/wiki/Switch [5] http://en.wikipedia.org/wiki/Ball_bearing [6] http://www.thebigbearingstore.com/6203-2rs-6203-zz-radial-ball-bearing-17x40x12/ [7] http://www.ask.com/home-garden/en8-steel-b84eb5e21bdcb2ef [8] http://www.tradeindia.com/suppliers/wiper-motor.html [9] http://en.wikipedia.org/wiki/AutoCAD Volume 4, Issue 5, May 2015 Page 460