Draw the profile of a cam to raise a valve with S.H.M. 3. The cam profile will be discontinuous. base circle pitch circle prime circle pitch curve; Q9 . Expert Answer. Cam Profile: The contour of the working surface of the cam. View 33-CAM profile for imparting uniform acceleration and uniform retardation motion to follower-16-Aug- from MECHANICAL MEE2004 at Vellore Institute of Technology. the displacement of follower is to take place with uniform acceleration and uniform retardation. Determine the maximum velocity and acceleration of the follower when the cam shaft rotates at 900 rpm. Follower**:** 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. To keep the valve fully raised through next 30; 3. Cams are used to convert rotary motion into reciprocating motion. Cam Profile: The contour of the working surface of the cam. In order to have acceleration in beginning and retardation at the end of stroke within the finite limits. (Q-6) [5] Q2) Draw the displacement, velocity and acceleration diagrams for a follower This must be done at a scale of 1:1 to use it to generate the cam profile. If the clutch is an old clutch, then uniform rate of wear assumption is more valid. The valve must remain in the fully open position for 20^{\circ} of cam rotation. The cam profile will be discontinuous. One basic rule in cam design is that this motion curve must be continuous and the first and second derivatives (corresponding to the velocity and acceleration of the follower) must be finite even at the transition points. 2. Then the follower lowers down during 150 o of the cam rotation with uniform acceleration and deceleration followed by Grooved camor closed cam (Figure 6-4): This is a plate cam with the follower riding in a groove in the face of the cam. The motion created can be simple and regular or complex and irregular. Cam Follower Design Terminologies. draw the profile of the cam (i) when the line of stroke of the follower passes through the centre of the cam shaft, and (ii) when the line of stroke of the follower is off-set by 15 mm. Draw the profile of disc cam to give uniform acceleration and retardation out stroke of 25 to A translating or a swing arm follower must be constrained to maintain contact with the cam profile. Divide these circles in appropriate divisions (30 degrees was used in this Draw the profile of the cam. with Uniform Acceleration and Retardation. Minimum radius of cam = 25 mm. Pitch Curve: The path of the tracer point. 1500 00 to 1200 uniform acceleration and retardation rise of 36 20.8 (a), (b) and (c) respectively. To raise the valve through 50 mm during 120 rotation of the cam ; 2. Design a cam for operating the exhaust valve of an oil engine. Harmonic Motion (SHM) followed by a dwell period of 30. through 40 mm in of revolution, keep it fully raised through 1/10 th 1 th 4 revolution and to lower it with uniform acceleration and retardation in 1/6 th revolution. Types of Cam Followers There are three types of cam followers, and since the type of follower influences the profile of the cam it is worthwhile considering the advantages and disadvantages of each type. During the next 90 of cam rotation, the follower returns to its original position with simple harmonic motion 4. To move outwards through 40 mm during 100 rotation of the cam 2. follower displacement. is required to move an offset roller follower with a uniform and equal acceleration and retardation on both the outward and return strokes. Cam profile drawings, for uniform acceleration and retardation The follower again turns to its original position with velocity during next half of three revolution . uniform acceleration & retardation Prob. cam rotation return stroke with Uniform acceleration and retardation for 90 cam from ME 35 at Anna University, Chennai The valve must remain in the fully open position for 20^{\circ} of cam rotation. The cam profile will be discontinuous. CAM profiles for combination of Study Resources Draw the cam profile. Determine max. velocity and acceleration during out stroke and return stroke if the cam rotates at 1000 rpm in clockwise direction. Cam profile: Construct base circle. Mark points 1,2,3..in direction opposite to the direction of cam rotation. Tracer Point: The point at the knife edge of a follower, Follower motion with uniform acceleration and retardation (UARM): Here, the displacement of the follower varies parabolically with respect to angular displacement of cam. 20.1. It is required to give equal uniform acceleration and retardation during opening and closing of the valve each of which corresponds to 60^{\circ} of cam rotation. Return of cam also takes place with uniform motion during remaining half CODE MET301 COURSE NAME MECHANICS OF MACHINERY CATEGORY L T P CREDIT PCC 3 1 0 4 Preamble: This course aims to introduce the students to the The valve remains closed during the rest of the revolution. https://www.joshuanava.biz/engineering-3/cam-follower-motions.html Base Circle: The smallest circle drawn, tangential to the cam profile, with its center on the axis of the camshaft. Uniform acceleration and retardation of follower motion Cycloidal motion follower; Uniform velocity motion; Q8 The size of a cam depends upon. Transcribed image text: - Design the cam profile to wise the point follower of Figure as shown with gravitational motion : Ve in with uniform acceleration and 42 in uniform retardation while the cam turns 100"; bold it at rest for 60" allow it to return to its original position with grav- tational motion while the can turns llo; and hold it at rest for the remainder of the cyck. To lower the valve during next 60; and 4. Uniform acceleration and retardation cams are used to controls the motion of linkages in complex machinery. 1500 00 to 1200 uniform acceleration and retardation rise of 36 mm, 1200 to 1800 uniform velocity rise of 12 mm, 1800 to 2400 dwell, 2400 to 3600 simple harmonic motion fall of 48 mm. Dwell for the next 30, 3. 1: draw the profile of disc cam to given uniform velocity motion to the knife edged follower during outstroke of 60mm during 1st half revolution. A flat-faced reciprocating follower has the following motion with uniform acceleration and retardation: Ascent for 80, dwell for 80, and return for 120. 21. Draw the profile of cam, if the axis of follower passes through the axis of cam. Lecture:3.3 Cam Page 7/37. The lift of the valve is 37.5 mm and the least radius of the cam is 40 mm. Draw the cam profile for conditions same with follower off set to right of cam center by 5mm and cam rotating counter clockwise. We shall now discuss the displacement, View 33-CAM profile for imparting uniform acceleration and uniform retardation motion to follower-16-Aug- from MECHANICAL MEE2004 at Vellore Institute of Technology. 7(a), (b) and (c) respectively. stroke with Uniform acceleration and retardation, for 120 cam rotation;dwell for 60 cam rotation; return stroke with Uniform acceleration and retardation,for 90 cam rotation; dwell for the remaining period. curves for cam profiles, Disc cam with reciprocating follower having knife edge, roller follower, Follower motions including SHM, Uniform velocity, Uniform acceleration and retardation and Cycloidal motion. 9. lift = 30 mm . Roller diameter = 15 mm . assuming that, there is no dwell between the ascent and descent, determine the lift of the valve, the flank radius and the acceleration and retardation of the The base circle diameter of the cam is 60 mm and the stroke of the follower is 20 mm. Generating a cam profile for uniform acceleration/retardation: Draw two circles with the following specifications: the base cam radius and the maximum follower displacement. To dwell for next 80 3. Uniform Velocity Motion The displacement, velocity and acceleration diagrams when a knife-edged follower 1- Displacement, Velocity and Acceleration Diagrams when the Follower Moves with Uniform Velocity:- stroke with Uniform acceleration and retardation,for 90 cam rotation; dwell for the remaining period. Cam lift 50 mm during 120 of cam rotation with uniform acceleration, = 2. Example Problem 3 (Uniform Acceleration and Retardation Follower) A cam, with a minimum radius of 50 mm, rotating clockwise at a uniform speed, is required to give a knife edge follower the motion as described below: 1. Draw the profile of a cam with oscillating roller follower for the following motion : (a) Follower to move outwards through an angular displacement of 20 during 120 of cam rota- tion. with uniform acceleration and retardation are shown in Fig. Intro to Mechanical Engineering DrawingLecture:3.3 Cam profile for roller follower with simple harmonic and uniform retardation motion Lecture 3.1: Cam profile for knife edge follower with uniform velocity motionIntroduction to technical drawing Mechanical Drafting \u0026 Design Using The Bullet-Journal Method in 11. A cam, with a minimum radius of 25 mm, rotating clockwise at a uniform speed is to be designed to give a roller follower, at the end of a valve rod, motion described be low : 1. Draw the cam profile for conditions same with follower off set to right of cam center by 5mm and cam rotating counter clockwise. The size of the base circle determines Transcribed image text: - Design the cam profile to wise the point follower of Figure as shown with gravitational motion : Ve in with uniform acceleration and 42 in uniform retardation while the cam turns 100"; bold it at rest for 60" allow it to return to its original position with grav- tational motion while the can turns llo; and hold it at rest for the remainder of the cyck. Q2 Which of the following statements is/are true for cam profile? Note that the acceleration is zero for the entire motion (a=0) but is infinite at the ends. The motion curve and velocity and acceleration curves are as shown. In order to draw the cam profile for a radial cam, first of all the displacement diagram for the given motion of the follower is drawn. through 40 mm in of revolution, keep it fully raised through 1/10 th 1 th 4 revolution and to lower it with uniform acceleration and retardation in 1/6 th revolution. Then the follower lowers down during 150 of the cam rotation with uniform acceleration and deceleration followed by a dwell period. stroke with Uniform acceleration and retardation, for 120 cam rotation;dwell for 60 cam rotation; return stroke with Uniform acceleration and retardation,for 90 cam rotation; dwell for the remaining period. Tracer Point The point at the knife edge of a follower, or the center of a roller, or the center of Follower motion with uniform acceleration and retardation (UARM): Here, the displacement of the follower varies parabolically with respect to angular displacement The cam lifts the follower for 120 o with SHM followed by a dwell period of 30 o. cam profile for uniform acceleration and retardation. Cam Profile The contour of the working surface of the cam. (11) Draw the cam profile for following conditions: Follower type = roller follower, off-set to the right by 5mm; lift = 30mm; base circle radius = 25mm; roller radius = 5mm; out stroke with SHM, for 1200cam rotation; dwell for 600cam rotation; return stroke during 1200cam rotation; first half of return stroke with Uniform velocity and second h 2. (1) Draw the cam profile for following conditions: Follower type = Knife edged, in-line; lift = 50mm; base circle radius = 50mm; out stroke with SHM, for 600 cam rotation; dwell for 450cam rotation; return stroke with SHM, for 90ocam rotation; dwell for the remaining period. A follower with Uniform Acceleration and Retardation (UAR) will accelerate and decellerate at the same rate. The line of motion of the follower passes through the axis of the cam. Design a cam for operating the exhaust valve of an oil engine. Draw the profile of disc cam to give uniform acceleration and retardation out stroke of 25 to a knife edge follower during first half of revolution. Due to infinite accelerations, high inertia forces will be created at the start and at the end even at moderate speeds. We see that the displacement diagram consists of a parabolic curve and may be drawn as discussed below : V0 = max velocity Construction of Cam profile for a radial cam Cam profile drawings, for uniform acceleration and retardation Negative acceleration tends to reduce the cam follower interface force, and if the neg Synthesis of cam profile using classical splines and the effect of knot locations on the acceleration, jump, and interface force of cam follower system - U Chavan, S Joshi, 2011 A In case of roller follower, trace B Uniform acceleration and retardation of follower motion. A displacement graph of a Radial Plate Cam for a Flat and Roller fonower_ Construct a Simple Harmonic Motion curve to lift 35mm in 180', high dwell for 30 z shown by a straight line, Uniform Acceleration and Retardation curve, to fall 35mm to the base line The shaft is 10mm r otation 30 botOm 20 240 210 270 awen fan SRM UNIVERSITY 19 09/10/2019 PPT/BB 20 09/10/2019 PPT/BB 21 Cams: Types of cams, 22 MODULE- II Types of followers, 10/10/2019 PPT Cams Displacement constant 12/10/2019 PPT velocity,Simple Harmonic Motion, 23 16/10/2019 BB Uniform acceleration and retardation cams are used to controls the motion of linkages in complex machinery. Cycloidal motion 12/3/2013 Dr. Mohammad Suliman Abuhiba, PE 20 . Draw the profile of the cam when line of stroke of the follower passes through the centre of the cam shaft. 6.2.3 Cam Shape Plate cam or disk cam: The follower moves in a plane perpendicular to the axis of rotation of the camshaft. Transcribed image text: QUESTION 2 Design the cam profile when the roller follower with the following data: 1. Access Free Introduction To Kinematics And Mechanisms profile for roller follower with simple harmonic and uniform retardation motion Grashof law Lecture 2.4: Acceleration diagram of four bar mechanism Lecture 2.5: Acceleration diagram for slider crank mechanism Kinematics, Dynamics and Page 8/37. Velocity and acceleration analysis using loop closure equation. Construct radial plate cams of given uniform velocity, simple harmonic motion, uniform acceleration and retardation to in-line knife-edge followers. The displacement, velocity and acceleration diagrams when the follower moves with uniform acceleration and retardation are shown in Fig.