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The purpose of this paper is to present a methodology for design, analysis and evaluation of cam‐follower systems used for the control of valve movement in internal combustion engines. The strategy begins with the inverse engineering of existing motor parts, designing them with the CATIA CAD Software and consequentially the created assembly is simulated using real time conditions in SimDesigner software, with the Adams Solver.

The cam profile is generated and the kinematic and dynamic analysis of the variable valve mechanism is presented. The whole mechanism is verified in a dynamics analysis to check the validity of the criteria for the follower‐cam system design. Comparisons with standard profiles of motion were made, while it is also evaluated in an experimental device, where the actual valve displacement was measured.

The variable valve lift mechanism is designed to have maximum lifts greater than the lift of the conventional mechanism, with the geometrical constraints, profile of forces, velocities and accelerations to be better, in terms of stresses and work required, than the design of conventional mechanisms.

The novelty of the paper is consisted in presenting an integrated simulation methodology in order to precisely model, in component and assembly basis, the follower cam mechanisms with variable valve lift, and using the available software to perform the kinematic and dynamic analysis. The proposed simulation methodology can be easily adapted by a design engineer to model and to analyzed kinematically and dynamically moving components and assemblies found in internal combustion engines and not only.

This paper aims to propose an elementary approach towards the measurement of a globoidal cam profile used in an automatic tool changer (ATC) of computer numerical control (CNC) machines.

A simple and unique online method has been designed for the profile metrology of the cam. This simple methodology will replace the traditional methodology of profile metrology of cam by coordinate measuring machine (CMM). A globoidal cam with an indexable turret and roller follower (rotating in an enclosed track) has been evaluated in our analysis. This analysis plays a significant role in the performance determination of the cam as well as the ATC of CNC machines.

A novel model has been designed and implemented to investigate the profile of a globoidal cam. The proposed methodology becomes an enhancement over the old methodology, i.e. measurement through CMM. Theoretical analysis and practical implementation prove the significance of the method.

An enhanced methodology to effectively measure the globoidal cam profile has been proposed. The practical implication of the proposed methodology remains for the CNC machine tool and ATC manufacturers. Finally, analytical explorations have been carried out to prove the validity of the proposal.

Introduces the reader to the concepts and benefits of electronic cam capability in electronic motion control systems. General mechanical cam operation is discussed and the concept of electronic cam is described. A “rotary knife” application is used to illustrate how electronic cam can increase the quality of motion and simplify programming.

CAST iron is arguably the most versatile of engineering materials and nowhere is this more evident than in the internal combustion engine.

THE Newall Engineering Co. Ltd., of Peterborough, has developed a machine for the automatic grinding of the convex surfaces of turbine blades. The machine has been developed to a requirement stated by an aero‐engine manufacturer on behalf of the Ministry of Supply.

In combination with dirigible craft provided with means for directing the same, power mechanism for actuating said directing means and means sensitive to turn of the craft, means for integrating the extent of turn and a separate device sensitive to acceleration, all connected to conjonitly control operation of said power mechanism.

An aircraft comprising in combination, a fuselage having an empennage and forward propulsive means, a disk‐shaped aerofoil mounted on said fuselage for universal inclination thereon, means for rotating said aerofoil, a plurality of rotary wing blades mounted for rotation with said disk‐shaped aerofoil, and means for retracting said blades into said aerofoil and for extending said blades outside of said aerofoil.

Considers the mathematical modelling of sewing machines. The machine with a rotary hook and with a feed mechanism driven by two triangle cams is studied. The behaviour of the system is described by a set of non‐linear autonomous ordinary differential equations. It is shown that, due to the timing belt extensibility, the actual relative position of the needle and the hook is different from that expected. This difference is a result of the conflict between the almost constant speed of the hook shaft and the fluctuating speed of the crank‐shaft caused by the reciprocating motion of working elements. The vibration of the belt increases with speed. Resonance increase of vibrations takes place when the shaft speed is equal to natural frequency or its fraction 1/n for n = 1, 2, 3, 4, 5.

This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of elastohydrodynamic lubrication (EHL), according to the cam wear prediction using Archard’s model. Cam–follower kinematic pairs always work under wear because of concentrated contacts. Given that a cam and follower contact often operates in the mixed or boundary lubrication regime, simulation of cam wear is a multidisciplinary problem including kinematic considerations, dynamic load and stress calculations and elastohydrodynamic film thickness evaluations.

Multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL are applied to obtain the dynamic loads, the time histories of contact pressure and the oil film thicknesses in cam–follower conjunctions to predict cam wear quantitatively.

The wear depth of the cam in the valve train of a heavy-load diesel engine is calculated, which is in good agreement with the measured value in the practical test. The results show that the cam–tappet pair operates under a mixed lubrication or boundary lubrication, and the wear depths on both sides of the cam nose are extremely great. The wear of these points can be decreased significantly by modifying the local cam profile to enlarge the radii of curvature.

The main value of this work lies in the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL, which can give good prediction for the wear of cam.

In combination with an aeroplane having a wing for sustaining purposes, an aileron pivotally supported adjacent the wing and adapted to float freely, and a hinged tab associated with the aileron and adapted in response to tilting relatively to the aileron during flight of the aeroplane to control the angular position of said aileron with respect to the air stream, a system for controlling the tab comprising a cam mounted to rotate about the pivot axis of the aileron, pilot actuated means for turning the cam relatively to the wing, a cam follower in operative engagement with the cam, and an operating connexion extending between the cam follower and the tab and operative to tilt the tab relatively to the aileron in response either to turning of the cam relatively to the wing or to relative turning of the cam and aileron, said cam being so designed that when it is in a neutral stationary position with respect to the wing and said wing is caused in connexion with flight to change its angle of attack from zero to stall it effects tilting of the tab into a position wherein it causes the aileron to assume substantially the same angle of attack as the wing and being also so designed that when it is in its said neutral stationary position with respect to the wing and such wing is caused to increase its angle of attack above the stall angle it positively maintains the tab in a fixed tilted position with respect to the aileron.