Necessary elements of a cam mechanism are shown in figure 4. A cam is a mechanical member which impart desired motion to the follower by direct contact. Introduction of cams and types of cam and followers. Since the cam follower is supported in a cantilever position, the mounting hole diameter should be prepared without play between the stud and the hole especially when heavy shock loads are applied. Take the line joining cam center and pivot point as reference and draw. A simple toy based on a cartoon character ed the handyman is controlled by a cam and follower. A cam is a rotating machine element which gives reciprocating or oscillating motion to another element known as follower. The radiusofcurvature of the cam changes as the cam rotates, while the radius of the camfollower does not change as it rotates when a cam and cylindrical camfollower roller lightly touch each other, their contact is a line. The follower arm swings or oscillates in a circular arc with respect to the follower pivot.
The device is classified according to the type of cam and follower that is within the system. D r s1 s1 stud diameter outer main dimensions diameter outer ring width threaded overall length shoulder height f d model no. Introduction a cam and follower is a device that transforms rotating motion from a cam to an oscillating motion from the follower. Cam and followerdynamic simulationautodesk inventor tutorial with caption and audio narration duration. Features of the cam follower outer ring seal side plate stud needle roller cage fig. The follower is pivoted at a suitable point on the frame and oscillates as the cam makes rotary motion. Cam followers come in a vast array of different configurations, however the most defining characteristic is how the cam follower mounts to its mating part. Cam and follower definition and types explained with images. A cam is a mechanical device used to transmit motion to a follower by direct contact. Cam and follower mechanism types and functions mechtics. Norton, design of machinery introduction to cam design. The follower is known as a radial follower if the line of. In this case, the mass m lies in the plane a and the balancing masses lay in the planes l. Analysis and simulation of cam follower mechanism using.
Usually a flat faced or roller companion to the camshaft that transfers the action of the camshaft to the rest of the valve train by sliding or rolling on the cam lobe. The smallest circle drawn, tangential to the cam profile, with its center on the axis of the camshaft. Patel me scholar, department of mechanical engineering, north maharashtra university, jalgaon abstract the objective of this paper is to modelling design and analysis of a cam and follower. From now we will term cam and follower mechanism as cam. Explain what a cam is, how it is used, and the typical types of cams identify force closed and form closed followers and explain the benefits and limitations of each describe the primary types of cam motion programs introduction to cam design source.
The size of the base circle determines the size of the cam. Camcentric adjustable cam followers are used where accurate positioning is required. Cam may be rotating or reciprocating while a follower may be rotating, reciprocating and oscillating. In order to quickly and accurately analyze the complex behavior of camfollower obliqueimpact system, a mathematical model which can describe separation, impact, and contact was established in this paper. Simulation model of cam follower mechanism with 345 polynomial cam profile. The main kinematic variables of the roller are the angular velocity and angular acceleration. Cam and follower mechanism is preferred over a wide variety of internal combustion engines because due to the cam and follower it is possible to obtain an unlimited variety of motions. An optimum design of cam mechanisms with roller follower.
Cam mechanism is a case of a higher pair with line contact. A camfollower forms higher pair as they have point contact at the junction. If i try to mate anything else to the cam, it locks in the highest or lowest position. Cam followers, yoke, and track rollers engineering data introduction selection guide engineering data interchange calculate your savings reduce your inventory brochure. Adding a cam to your mechanism is another important requirement when you design and build going packaging machines. The relevance and role of cams in modern machine systems has made their continuous study necessary and.
The crank which is the rotating disc, the slider which slides inside the tube and the connecting rod which joins the parts together. The point at the knife edge of a follower, or the center of a roller, or the center of a spherical face. Outer ring seal side plate stud mavin the webstore. This is the maximum distance that the cam pushes the follower when the valve is open. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Cam follower background and theory me 4201 section 4. Cam is a mechanical member for transmitting a desired motion to a follower by direct contact. Machine design, constant force action manual typewriters, vol. Cam and follower mechanism is a widely used method of motion transformation. Yoke type cam followers are available with and without seals, and with crowned outer rings.
I have attached another file to understand the connection betwwen the cam and follower. They are particularly useful for reducing clearance or. The coordinates of the visualized cam contour coordinates can be used in the cnc milling machine for the production of the real cam. Modelling, design and analysis of cam and follower a. In a cam follower pair, the cam normally rotates while the follower may translate or oscillate. A cam follower, also known as a track follower, is a specialized type of roller or needle bearing designed to follow cam lobe profiles. The forces to open the intake and exhaust of a conventional valve train system are strongly influenced by the stiffness and the damping of the valve spring and the valve seat, masses, geometries and frictional behaviors of contacting elements of valve train components.
Lab manual to study various types of kinematics links, pairs, chains. The velocity of any cam follower can be calculated using the deferential method provided you have the equation relating the angular. The cam drives the two tools positively away from the danger zone the plunger is moved to the left, and the workhead is moved upwards. Cam and follower mechanism and their types mechanicalmaster. Module 4 drives and mechanisms lecture 1 elements of. Another part associated with the cam is called follower. Introduction the cams are usually rotated at uniform speed by a shaft, but the follower motion is predetermined and will be according to the shape of the cam. The driver is called the cam and the driven member is called the follower. A familiar example is the camshaft of an automobile engine, where the cams drive the push. The contour of the working surface of the cam tracer point. Clevis mounting provides support on both sides of the cam follower and permits use of a high strength pin. The scheme of camfollower me hafig 1 shows the scheme of a camfollower mechanism.
Cam is a rotating element which provides an oscillation or reciprocatory motion to another part connected with the cam. Modeling and nonlinear response of the camfollower. Moreau timestepping method was employed to solve the linear. In cam follower system the cam size minimization is one of the important topics in cam mechanism design. Cam mechanisms are widely used because with them, different types of motion can be possible. However, the manufacturing of cams is expensive and the wear effect due to the. Problem on offset knife edge follower cams and followers kom tom duration. The main purpose of this work is to present a complete kinematic analysis of the roller motion in translating camfollower mechanisms with translating roller followers. Mechanical engineering tutorials solved problems based on cam profiles. Description of the cam follower p 3 featuresofthecamfollower the cam follower is a compact and highly rigid bearing with a shaft.
As we increase the contact force, the cam and follower deflect squash together, like a car tire against a road surface and the contact line becomes a narrow. Whenever i try to mate the follower to the inner profile of the cam, the follower ends up crooked at certain points along the cam. The driver is called cam and driven is called follower. Cams classification of cams and followers, nomenclature, description and analysis of follower motion, pressure. Cam and follower combination belongs to the category of higher pairs.
A cam follower, also known as a track follower,1 is a specialized type of roller or needle bearing designed to follow cams. This analysis is an important step for fixing an optimum size of a cam and. Taylor synopsis a general background to the consideration of tribological factors in cam and follower design is presented as a prelude to the description of the development of computer software for the analysis of the lubrication of any cam and tappet form. With the rotation of the cam, the follower the shaft with the roller at bottom in the above picture gets oscillated or translated according to the profile of the cam. Module 10 lecture 1 kinematics of machines youtube. Tushar kiran et al analysis and simulation of cam follower mechanism using polynomial cam profile 214 int. Cams can provide unusual and irregular motions that may be impossible with the other types of mechanisms.
Introduction, types of cam, types of follower radial cam offset follower end cam types of cam and follower cam and follower real life examples cam and follower nptel cam and follower mechanism pdf. Currently i am using wrap and then deboss to create the cam profile. The cam and the follower have a line contact and constitute a higher pair. Cam follower with tapped greasing hole model cft b3. Generally, manual handling in industries has been reduced to the minimum. A according to type of shape 1 radial or disc cam 2 cylinrical cam 3 translation or wedge cam 4 conjugate cam 5 globoidal cam 6 spherical cam types of cams 2. Predictions of cam follower wear in diesel engines. Analysis and usage of cams and their followers engineering. Slider crank mechanism is mainly used to convert rotary motion to a reciprocating motion or vice versa slider crank mechanism is composed of three important parts. What are the applications of different types of cam. The transient impact hypothesis was extended, and the oblique collision model was established by considering the tangential slip. It is normally connected with a prime mover, which rotates it. Camshaft is the brain of the engine must include cam lobes, bearing.
Cam and follower design basics design of cam profiles. Computer aided kinematic and dynamic analysis of cam and. Proper design of cam and follower is required for perfect tuning between opening and closing of valves with cam shaft speed. This article will discuss the calculation method of the velocity of cam follower. We will discuss the differential method for finding relation between the angular velocity of a cam and the linear velocity of a follower. As the cam rotates in an anticlockwise direction, the. Clearance the radial internal clearances of cam followers are shown in table 4. This is likely to prevent further damage to the mechanisms.
One response to kinematics of the camfollower mechanism. These problems have been solved by many methods using graphical methods 1, 2, which take the effect of cam motion on the curvature of the cam profile and the amount of offset of the follower that need in a specific. Cams are used in internal combustion engines to provide a specific prescribed motion to a valve train system. Cam followers, yoke, and track rollers engineering data. Cam follower mechanical engineering general discussion. The follower is chosen based on the surface in contact and the motion of the follower. If there is a jam, the camfollower cannot return move with the cam. This introduces a little bit about inverse kinematics, and a little on motion design with motiondesigner. Experimental study of engine camfollowers enrico ciulli 1, bruno piccigallo 2, dagoberto vela 1department of mechanical, nuclear and manufacturing engineering, university of pisa, italy email.
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