Mechanical Engineering-Machine Designing-1

Explore the gears introduction, tracing development from ancient China to the 1970s. Learn how diameter, teeth count, and fit profile influence velocity ratio and gear design.

Examine types of gears, including helical, double helical, and internal gears, and learn how gear transmissions convert rotary to linear motion while achieving various velocity ratios.

Explore key gear terms such as gear diameter and center distance, addendum and dedendum circles, working depth, space, thickness, profile, fillet radius, face, and circular orbit.

explore basic formulas in gear design, including velocity ratio and the inverse relation between rotation counts and gear diameters, and distinguish pitch diameter, module, and inch versus metric systems.

Explore the pressure angle in gear profiles, showing how it affects interference, noise, and efficiency, with ideal values of 14.5°, 20°, and 25°, and related addendum and module relationships.

Explore the laws of gearing, showing velocity ratio inversely proportional to center distance and how center lines and perpendiculars identify a point on the gear circle to avoid interference.

Explore the laws of gearing by examining how noise and interference arise in gear systems and how center distance should be set to minimize interference.

Learn two forms of gear tooth profile generation - profiles produced by a circle rolling without slipping outside or inside a circle - with dynamic constructions and practical demonstrations.

Model cycloidal gear teeth through circle-based construction, defining addendum circles, base lines, and angular divisions to create a precise tooth profile.

Explore constructing an involute tooth profile through circle geometry, base circle, tangents, and addendum, and compare involute and cycloidal gears for strength and velocity ratio.

Explore spur gear design by calculating power, line velocity, center distance, and gear material, while applying pressure angle, service factor, and data inputs to master the design formulas.

Explore permissible working stress and how load charts guide spur gear design. Apply pitch line velocity thresholds (12–12.5 m/s, up to 20 m/s) to compute gear life values in modeling.

An in-depth design of a spur gear pair, with driver and driven gears at 800 and 200 rpm, calculating pitch diameter, center distance, tooth count, and essential force variables.

Calculate spur gear profile effects by applying addendum factors, pressure angle values, and the solid box equation, using table-based numbers from the lecture.

Explore spur gear modeling, including selecting shaft key sizes, determining gear diameter, and designing custom gear sizes using the first method for gear modeling.

Model spur gear-2 by manually drawing addendum and base circles, setting radii (such as 72) and a broughton profile, then mirror and trim to finalize.

Explore design of helical and double helical gears, identifying left- and right-handed gears, and applying helix angle, normal and circular pitch, and base-data formulas for gear design.

Explore modeling the helical gear by constructing the main circle and another circle, defining diameters and radii, and determining the helix angle for left- or right-handed gears.

Design bevel gears by selecting diameter, tooth count, and length, then determine the bevel angle, often 45 degrees for certain tooth counts, and translate sketches into 3d modeling.

Learn to design bevel gears with formula-based calculations for diameter, pitch angle, tooth numbers, addendum, and dedendum, and model gear arrangements using offset and flank radius concepts.

Model a bevel gear by constructing a center line, offset distances, and multiple circle profiles; then apply the tangent constraint and a circular pattern to finalize the geometry.

Designing of worm gear-1 analyzes worm gear geometry, velocity ratio, starts and pitch, and lead angle through formulas and table-based calculations.

Apply formulas and tables to design a worm gear system, solve numerical problems, and determine velocity ratio, center distance, and key dimensions.

Model the worm by building its profile from the center, applying a 180-degree revolution, and using 56-degree and 44-degree references, tangent circles, and plane sketches for assembly.

Model the worm gear by defining the diagram and outer diameter, drawing two circles with the same center, and using sketches, mirroring, and circular pattern to complete the profile.

Explore shaft designing as the rotating machine element that transmits power, analyze forces and stresses, perform mathematical calculations, and study practical examples to understand shaft design challenges.

Examine the types of shafts and their role in transmitting power from source to machinery through gears, and compare transmission shafts with machine shafts in design and strength.

Identify standard shaft sizes and available raw material sizes in local markets. Visit the raw materials store to understand availability and the data used for different materials.

Explore how shafts transmit power and endure stresses, including shear stress and bending stress from gears and pulleys, with emphasis on when one force dominates.

This course covers shaft designing for strength and rigidity to transmit power and motion in machines, outlining four loading cases: dominant torque, dominant bending, their combination, and special combined loading.

Neglect bending moment and analyze twisting moment only; compute torque from power and speed, size the shaft via the polar moment of inertia and allowable shear stress.

Analyze bending moment dominated shaft design by applying bending stress formulas using moment of inertia and radius, with a cantilever example and neglecting twisting moment.

This lecture examines a shaft subjected to combined twisting and bending moments, using a transmission chart to compute maximum moments and determine the required shaft diameter.

This lecture analyzes a shaft subjected to combined twisting and bending moments, resolves vertical and horizontal forces, determines reactions, and computes the bending moment and maximum torque.

Analyze a shaft subjected to fluctuating load by applying combined bending and twisting moment formulas and stress criteria to determine the required shaft size.

Explore a shaft subjected to axial load with combined moments, applying the bending moment formula and the ratio of the inner diameter to the outer diameters to determine design values.

Design shafts to satisfy torsional rigidity by sizing the diameter to limit angular deflection under maximum twisting moments, applying theta = tl/(jg) with g and l.

learn to select shaft keys by analyzing twisting moment, using a diameter-based table to determine key size and length, guided by material properties and stress calculations.

Explore fits and tolerances for keys, using a table of tolerances to determine shaft sizes and achieve the desired dimensions in mechanical design.

This lecture presents two shaft modeling methods, including extruding a shaft of set length and using a center line approach, to design step-up shafts with varying diameters and keys.

Explore the lever principle with a fixed fulcrum, showing how adjusting the effort–distance changes load lifting and mechanical advantage, and preview the related formula.

Explore the three lever types, first, second, and third class, by examining fulcrum position, load, and effort, with the knee joint as an example.

Explore lever formulas for simple levers, focusing on fulcrum position, effort, and load to determine balance and required effort.

Apply twisting moment concepts to hand lever design by equating moment to force times distance, using linked dimensions and hinge loads to verify feasible performance.

Explore the calculation of bending moments and bending stress for a hand lever design, using simple formulas to determine end moments, section dimensions, and material effects.

Examine the design of a foot lever, calculating bending and twisting moments to determine shaft diameter, key lengths, and overall dimensions using design formulas.

Explore the design procedures for a bell crank lever, applying first-class lever principles to calculate loads, bending stresses, shaft dimensions, and bushings and clearances.

Modeling a bell crank lever involves defining internal and external dimensions, locating the fulcrum, and drawing center lines and circles to ensure accurate planar alignment.

Explore how springs behave as elastic bodies under load, distorting and absorbing energy. Examine applications in suspension systems, aircraft landing gear, vibration damping, and spring index specifications.

Explore different types of springs, including helical and laminated leaf springs, and learn how they store and release energy while serving as vibrational dampers and shock absorbers in mechanisms.

Explore materials for helical springs, evaluate properties for different loading scenarios, and learn to select wire diameter, alloy, and coating to balance strength, corrosion resistance, and cost.

Identify key spring terms such as solid length, maximum compression, number of coils, coil diameter, and spring index, then apply end configurations and formulas for length and pitch.

Analyze stresses in a helical spring, focusing on diameter, spring index, and deflection, and apply two key equations to compute shear stress.

Analyze spring size by calculating outer and wire diameters, apply the deflection formula to find deflection under load, and compare scenarios to select final dimensions.

Understand how springs in series and parallel determine deflection and load distribution, using spring rate and the concept of combined stiffness to analyze system behavior.

Master spring selection by evaluating spring rate, force, and deflection, and choosing ends and materials for specific environments, using calculation tools to size diameter and predict deflection.

Explore how bearings enable relative motion between machine elements and how to select bearings based on loads acting on the bearing and dimensional considerations, including lubrication types and methods.

Explore sliding and rolling bearings, including ball, cylindrical roller, spherical, needle, and thrust types; learn selection factors like radial and axial loads, misalignment, lubrication, and bearing nomenclature.