Mechanisms And Mechanical Movements - Franklin Day Jones
The Industrial press (1918)
In Collection
#5223

Read It:
Yes
Machinery, Kinematics of, Mechanical movements

This treatise on mechanisms and mechanical movements is intended for designers of machinery and for all interested in originating new mechanical devices or in developing and perfecting those now in use. In view of the fact that there is an almost endless variety of mechanisms, it might seem impracticable to deal with such a broad subject in a single volume of this size. As the classes of mechanisms, however, which differ radically in principle, are few in comparison with those which simply vary in form, it was considered not only practicable, but very desirable, to present in one volume a variety of mechanical devices representing different types of mechanisms and selected especially to illustrate important fundamental principles.

The designers of machines or mechanisms in general are constantly engaged in the solution of problems pertaining to motion and its transmission. The motion derived from some source of power must be modified to produce certain effects, and various changes in regard to velocity, direction, and time of action may be necessary. Frequently, the same result may be obtained by forms of mechanisms which differ entirely in principle and effectiveness, and it is essential to employ an approved method. The purpose of this treatise is not only to explain how various mechanical motions may be produced and controlled, but to show the relation between the theoretical and practical sides of the subject. The examples include many ingenious mechanical combinations and are practical designs which not only illustrate the principles involved, but indicate exactly how those principles are applied. An understanding of these concrete examples will prove much more beneficial than a study of abstract theories, which only give an inadequate conception of their application in the design of mechanisms of various types.

Many technical graduates and draftsmen understand the proportioning of parts to safely withstand certain stresses more thoroughly than they do the use of different combinations of parts either for transmitting, reversing, or otherwise modifying motion to secure whatever action or effect may be required. Frequently, the stress involved or the strength of the parts is of little importance, and the principal problem is one pertaining to motion, especially in the development of new forms of mechanisms. While a general knowledge of mechanisms and their possibilities could be obtained by studying miscellaneous designs, this would involve considerable duplication of effort, because so many mechanical devices which vary as to form and purpose are identical in principle. The different forms of mechanisms described in this volume represent many distinct types, and they have been classified and arranged so that various modifications of the same general type may readily be compared.

The columns of Machinery were of valuable assistance in supplying information and illustrations regarding various types of mechanisms, especially of the classes common to the machine- building and machine-tool fields. Special mention should be made of the excellent examples of mechanisms obtained from the contributions of G. W. Armstrong and G. M. Meyncke. The study of mechanical movements is of especial importance at the present time, owing to the increasing use of automatic machines in almost every branch of manufacture, and this treatise is published in the belief that it will be of practical value to many designers, draftsmen, mechanical engineers, and inventors engaged in originating and planning new developments.



CONTENTS

Chapter I
MOTIONS AND GENERAL METHODS OF TRANSMISSION IN MACHINES
Classes of Motion - Velocity and Acceleration - Velocity Ratio - Angular Velocity - Link Mechanisms - Universal Joint - Straight-line Motions - Toggle Joint - Pantograph Mechanisms - Transmission by Frictional and Toothed Gearing - Transmission by Flexible Bands, Ropes, and Chains - Trains of Mechanism - Analyzing Action of Epicyclic Gearing

Chapter II
SPEED-CHANGING AND CONTROLLING MECHANISMS
Types of Mechanical Speed-changing Mechanisms - Arrangement of Cone-pulley Drives - Combination of Cone pulley and Gearing - Geared Speed-changing Mechanisms - Frictional Speed-changing Devices – Multiple disk Type of Speed-changing Mechanism - Friction Disk and Epicyclic Gear Combination - Governors of Centrifugal and Inertia Types

Chapter III
CONVERSION OF ROTARY AND RECTILINEAR MOTIONS
Crank and Connecting-rod - Relative Motions of Crank-pin and Cross-head - the Eccentric - the Crank and Slotted Cross-head or Scotch Yoke - Cylinders which Revolve about a Stationary Crank - Cylinders which Revolve within an Eccentric Track - Rack and Gear Combination - Methods of Doubling Stroke - Single- and Double-stroke Toggle Mechanisms - Press-bed Motions for Flat or Cylinder Presses - the Napier Motion - Reciprocating Motion from Epicyclic Gearing

Chapter IV
REVERSING MECHANISMS
Intermediate Spur Gears for Reversing Motion - Bevel Gear Type of Reversing Mechanism - Reversal of Motion with Friction Disks - Operation of Reversing Clutches - Controlling Point of Reversal by Special or Auxiliary Mechanism - Planer Reversing Mechanism - Reversal of Motion through Epicyclic Gearing - Automatic Ratchet Reversing Mechanism - Automatic Control of Spindle Reversal - Automatic Variation in Point of Reversal - Reversal of Motion after Predetermined Number of Revolutions

Chapter V
QUICK-RETURN MOTIONS
Quick-return Motion from Crank and Oscillating Link - Whitworth Quick-return Motion - Modification of Whitworth Motion - Quick-return Motion from Elliptical Gearing - Eccentric Pinion and Elliptical Gearing for Quick-return Motion

Chapter VI
INTERMITTENT MOVEMENTS
Ratchet Gearing - Ratchet Mechanisms for Releasing Sprockets - Automatic Disengagement of Ratchet Gearing - Escapements - Automatic Reduction of Intermittent Movement - Gearing for Uniform and Variable Intermittent Motion - High-speed Intermittent Gearing of Moving Picture Projector - the Geneva Type of Intermittent Gearing - Intermittent Gears for Shafts at Right Angles - Adjustable Intermittent Motion - Automatic Variation of Intermittent Motion - Automatic Indexing Mechanism - Action of an Adding Mechanism

Chapter VII
IRREGULAR MOTIONS
Plate Cams - Positive Motion Cams - Return Cam for Follower to Secure Positive Motion - Yoke Type of Cam Follower - Inverse Cams - Wiper and Involute Cams - Cylinder or Barrel Cam - Automatic Variation of Cam Motion - Varying Dwell of Cam Follower - Automatic Variation of Cam Rise and Drop - Sectional Interchangeable Cams for Varying Motion - Mechanism for Engaging Cams in a Group Successively - Obtaining Resultant Motion of Several Cams - Double-shifting Cam

Chapter VIII
DIFFERENTIAL MOTIONS
Differential Screw - Chinese Windlass - Differential Motions from Epicyclic Gearing - Compound Differential Gears for Varying Speeds - Differential Motion between Revolving Screw and Nut - Differential Feeding Mechanism for Revolving Spindle - Application of Floating Lever Principle - Controlling Mechanisms for Steam Steering Gears - Substitute for Floating Lever - Differential Governors for Water Turbines - Differential Gearing of Automobiles - Speed Regulation through Differential Gearing - Differential Action through a Cam-controlled Gear - Differential Mechanism of a Gear-cutting Machine - Differential Hoisting Mechanism - Differential Speed Indicator

Chapter IX
CLUTCHES AND TRIPPING MECHANISMS
Controlling Motion by Means of Clutches - Positive and Friction Clutches - Multiple-disk Friction Clutches - Rapid-acting Multiple-disk Clutch equipped with Brake - Magnetic and Induction Clutches - Clutches that Automatically Disengage - Automatic Tripping Mechanisms for Stopping a Machine or some Moving Part - Breakable Pins to Prevent Overload - Automatic Clutch Control to Prevent Overload - Pressure of Frictional Gearing varied according to Load - Automatic Relief Mechanisms for Forging Machines - Automatic Speed-limiting Devices - Electromagnetic Tripping Devices
Chapter X
AUTOMATIC FEEDING MECHANISM
Automatic Feeding Attachments having Inclined Chutes - Attachment for Automatically Feeding Pinion Staffs - Magazine Attachment for Narrow Bushings - Revolving Magazine Attachment - Hopper Feeding Mechanism for Screw Blanks - Simple Arrangement for Feeding Shells with Closed Ends Foremost - Feeding Bullets with Pointed Ends Foremost - Feeding Shells Successively and in any Position - Feeding Shells Successively and Gaging the Diameters

Product Details
LoC Classification TJ175 .J6
No. of Pages 310
Height x Width 240 mm