29-01-2013, 11:14 AM
MODIFIED FIXTURE DESIGN FOR THE MEASUREMENT OF TDC OF THE PISTON
MODIFIED FIXTURE DESIGN.doc (Size: 3.97 MB / Downloads: 49)
ABSTRACT:
Today’s automotive world is changing rapidly due to advancement in technique. Several changes have occurred in production, manufacturing and assembly fields with new techniques. We have proposed a new technique using sensors to measure the value of TDC. We also have designed a fixture for mounting these sensors. This is just a small venture of several revolutionary breakthroughs which have and will be done in the fascinating field of automobile engineering in this area of globalization and advancement.
INTRODUCTION:
This project mainly concentrates on the measurement of the TDC of the piston using advanced techniques. Presently dialguages have been used for this purpose. But it has many disadvantages. Dial gauges have got more moving parts than other types. Due to more moving parts, the friction is more. Accuracy is less. Any slackness in moving parts reduces the accuracy considerably. It also causes sagging and backlash error. So a fixture is designed for S2, S3, S4 engines to set the piston in the prescribed limit using the sensors for accurate setting. The fixture is very compact and designed on the basis of reducing labor fatigue, increasing productivity and to gain more accuracy. The design is designed in such a way using advanced technology to overcome the conventional method.
METHODOLOGY:
This fixture is designed on the basis of improving productivity and efficiency. It is designed using soft wares like PRO-E, CAD/CAM. The use of sensors has enhanced the success of this project. This is a simple design which overcomes a major problem faced by many companies.
CONSTRUCTION OF FIXTURE:
The fixture consists of five major parts namely:
• Base frame
• Shaft with sliders
• Stoppers(for S2 and S3)
• Sensors
• Display
To maintain linearity, common locating pins are provided and to maintain rigid fixing magnetic bushes are provided at common locations for all the three engines.
The base frame is made up of cast iron mostly. It consists of handles at its front and rear end. A cylindrical shaft is connected to the base frame by means of a holder. The slider consists of cylindrical edges which are connected to the shaft in such a way that they can be adjusted easily along the shaft. The shaft also consists of stoppers. Depending upon the cylindrical bore centers of S2 and S3, stoppers are provided at required positions.
DESIGN DESCRIPTION:
The purpose of the design description is to show how a design meets its requirements. It consists of a textual description, liberally augmented with pictures, architecture diagrams, schematics, structure charts and whatever else is necessary to fully describe the design. The complete design was made with the use of CAD/CAM system. The attention was focused at reliability, complexity, simplicity, low weight and affordability.
The main objective of an information model is the description of types of ideas, facts and processes which together form a model of a portion of interest of the real world. The possibility of implementing these information models in a computer application has introduced improvements in the time, cost and set up of the manufacturing process.
WHAT IT CAN DO?
It operates in a completely non-contact mode and this are not subjected to any mechanical wear. Moreover they are insensitive to any extreme environmental conditions and thus are an ideal choice for applications, in which absolute reliability and robustness is needed and superior switch accuracy and high switch frequencies are required. This is the reason why millions of inductive proximity switches are found in automatic processes – in machine construction as well as in automotive field, in chemical apparatuses, in ware houses and conveying systems, in the textile or packaging industries.
WHAT MAKES IT SO SPECIAL?
Inductive proximity switches are able to recognize metal objects at a distance of 100mm. for this purpose they are used in various constructions – from cylinders with diameter as from 3mm up to rectangular sensors with an edge length of 180 X 180 mm. their housings come in a number of different synthetic materials or metals, and thus are suitable for a large number of applications. Their electric properties comprise 2, 3, 4 wire DC, AC, NAMUR and AS-interface.