Elements of Mechanics and Machine Design: A Treatise on Theoretical Mechanics, Methods of Calculating the Strength and Dimensions of Parts Subjected to Various Kinds of Stresses, Mechanical Power Transmission Problems, and the General Procedure in Designing Important Machine MembersErik Oberg |
Common terms and phrases
angles applied assumed back-gear beam bearing belt bending body calculations cast iron cent center of gravity central gear compressive stress cross-section dead gear deflection determined diameter diametral pitch direction distance driven gear driving arm elastic limit energy Epicyclic Gear Epicyclic Train equal example factor of safety feet per minute feet per second fiber flywheel foot-pounds force acting given Hence hook horsepower idler inch-pounds inertia internal gear keyways length lever load lubrication Machinery Fig material maximum stress mechanical metal method moment of inertia motion multiplied number of teeth obtained P₁ P₂ pinion plate pounds per square pressure principle pulleys radius ratio resistance revolutions per minute rotation section modulus shaft shearing stress shown in Fig speed spring square inch steel strength of materials subjected surface tensile stress tension thickness tion torsional transmitted ultimate strength values velocity weight wheel width
Popular passages
Page 37 - Every body continues in its state of rest or of uniform motion in a straight line, except in so far as it may be compelled by impressed forces to change that state.
Page 106 - The principal conclusions to be drawn from the results of this research may be briefly stated as follows: 1. The length of tube, between transverse joints tending to hold it to a circular form, has no practical influence upon the collapsing pressure of a commercial lap.welded steel tube so long as this length is not less than about six times the diameter of the tube.
Page 31 - A force has three characteristics which, when known, determine it. They are direction, place of application, and magnitude. The direction of a force is the direction in which it tends to move the body upon which it acts. The place of application is generally assumed to be a point, as the center of gravity. The magnitude is measured in pounds, as already stated.
Page 14 - The perpendicular distance of the center of gravity of a triangle from the base is equal to one-third of the altitude. The center of gravity of a parallelogram is at the intersection of its two diagonals; consequently, it is midway between its sides.
Page 39 - If a body is acted upon by several forces, it is acted upon by each of these as if the others did not exist. This is true whether the body is at rest or in motion. In other words, if two or more forces act upon a body at the same time, each produces exactly the same effect as if it acted alone; the total effect or resultant motion of all the forces may be found by a diagram in the same way as the resultant of forces is found.
Page 37 - ... line, unless it is compelled to change that state by forces impressed thereon. Law 2. The alteration of motion is ever proportional to the motive force impressed ; and is made in the direction of the right line in which that force is impressed. Law 3. To every Action there is always an equal Reaction: or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts. Mach has this to say (1883, p.
Page 22 - ... the sum of the moments of the forces which tend to turn the body in one direction must be equal to the sum of the moments of those which tend to turn it in the opposite direction about the same axis.
Page 42 - For convenience, this may be called a simple pendulum, and any pendulum in which the weight is not so concentrated, is a compound pendulum. Strictly, however, a true simple pendulum is merely an ideal conception — it is a particle of matter suspended by a weightless cord, and capable of vibrating without friction, while any pendulum that can be actually constructed is a compound pendulum. The length of a pendulum is the distance from, the point of suspension to a point lying below the center of...
Page 33 - Parallelogram of Forces. — If two forces applied at a point are represented in magnitude and direction by the adjacent sides of a parallelogram...
Page 107 - The apparent fiber stress under which the different tubes failed varied from about 7000 pounds for the relatively thinnest to 35,000 pounds per square inch for the relatively thickest walls. Since the average yield point of the material was 37,000 and the tensile strength 58,000...