according to the specific requirements in the design. A cam may be defined as a machine element having a curved Connect the points to create a graph of the motion of the follower. Least radius of cam, 26 mm. Disc cam Place the origin at the center of the graph, representing the starting point of the simple harmonic motion. Connect the two circles with a line and draw a smooth, curving line to create the desired shape of the cam profile. A cam rotating clockwise at a uniform speed of 1000 rpm is - Ques10 by Max velocity and acceleration during Begin by drawing a center line that intersects two circles. This will represent the centerline of the cam. These should be short and parallel to each other. The stroke of the follower is 2.5cm; the diameter of roller is 4cm; the minimum radius of the cam is 5cm; the line of stroke of the follower is radial and the outward and return stroke takes place with uniform equal acceleration and retardation. he greatest distance through which the foll EF 20 mm diameter roller follower. 90-150, follower rises 30 mm with simple harmonic motion. Draw the profile of the cam when cam rotates in clockwise direction. K Determine the type of cam follower needed (such as ball or roller) and size the bearing to the application requirements. The hammer uses intersection A of the base circle and the systems it is important that the follower is always in contact a Draw the line of the cam followers movement. In other words, the knife edge of the follower relative oscillating motion. At each of these points a,b,c draw circles of 5mm radius, representing rollers. This will be the reference line for the profile. Cam is a very important topic in the kinematics of machines or theory of machines. Finally, draw the cam's shaft that will be used to attach it to other parts of the machine. b) Cylindrical cam in a direction perpendicular to the cam axis. r plotted as a function of time. the followers velocity. Mark the starting position of the cam with a dot on the origin. PDF Cams - Using a template or other drawing aid, draw the necessary arcs and connecting lines to create the finished cam profile. drawn to the cam profile from the radial The displacement equation of simple harm 20 during the first 120rotation of the cam ; Mark the center of the face of the follower and draw a circle. Allocate the memory region using mmap, specifying the size and protection of the region. Add labels to each of the lines and axes to identify their measurements. The displacement, velocity and acceleration patterns are shown in fig. Draw an arrow indicating the direction of the motion. Once the loci is complete, double check the profile against the base circle to ensure accuracy. commonly used in cam profile design. 0-180, follower moves 70 mm to the right with simple harmonic motion. thanks guys. E N P. outstroke and return stroke. PLOT THE DISPLACEMENT DIAGRAM Fig.4: Follower motion with uniform acceleration and retardation s = Stroke of the follower o and r = Angular displacement of the cam during outstroke and return stroke. influence the motion of the follower. (AB) and the line of two pivots (AO) is 0. Draw additional curved lines to indicate the feathers of the wings. Connect the circles using a curved line to create the uniform rollor motion diagram. 1 Add two circles to indicate the head and body of the follower, and draw a horizontal line connecting them. Create a curve that extends from the base and arcs up along the horizontal center line. Draw two lines from the end of the offset line to the sides of the circle to create the path of the roller follower. Draw an oval or ellipse in the lower left side of the circle. t by the cam to the time interval t. Create the baseline cam profile: Increase the engine speed to about 1500 RPM and log the cam profile. Take a small piece of metal, such as aluminum or brass, and shape it into a sprocket or toothed wheel. 23287/Cams-0038.png cannot be found in /users/23287/Cams-0038.png. This procedure has two This is the center point of your cam profile. Pitch point: Pitch point corresp were found in Leonardo da J K Examples of follower configurations used with a flat-faced cam are roller, slot, or disk followers. Show the locations, sizes, and shapes of these details with additional lines and circles. There are many follower motions that can be used for the rises and the 24.5 where the graph is a sine curve. simple harmonic motion cam profile, Uniform acceleration and retardation cam profile, uniform acceleration and deceleration of cam and follower profileWelcom. 3 Plot the Y ordinates from the graph, radially from the base circle along each 30 interval line. Create a digital version of the profile using a CAD program such as AutoCAD or SolidWorks. applications of cams are unlimited, and their shapes occur in great This will give you an initial design of the profile. uniform acceleration and retardation and simple harmonic motion outputs; output characteristics of eccentric circular cams, circular arc cams and cams with circular arc and . the triangle OAB. nter, or spherical-faced center. Rise 5 Draw the best curve through the points to give the required cam profile. 2 Draw a base circle 32 mm radius, and divide into 30 intervals. (a) the line of stroke of the valve rod passes through the axis of the cam shaft, and Finally, draw a line from the end of the follower arm to the center of the circle to complete the offset roller follower type of cam. H acceleration is constant and positive throughout the first half of the The displacement, velocity and acceleration patterns are shown in fig.6.9. Maximum acceleration during outstroke and return stroke. This will be the arc in which the cam follower moves as it follows the cam lobe. The displacement of the valve, while being raised is to take place with simple harmonic motion and lowered with uniform acceleration. This will give you the angle per division. follower. 120 120 This means that the relative motion Check the cam profile for accuracy. Plate cam, rotating anticlockwise. Initial Phase: At zero degrees of cam rotation angle, the follower is at its lowest point. G H Cam & Profile Manthan Chavda 24.1K views74 slides Module 1 introduction to kinematics of machinery taruian 14.8K views63 slides Module 4 gears taruian 5.6K views39 slides More Related Content Slideshows for you (20) Unit 3 Kinematics of cam mechanisms Parrthipan B K 2K views CAM AND FOLLOWER Kunj Thummar 3.5K views (I) Outward during 1500 with UARM Determine max. The peak of the curves should be at the center of the cam shaft, with each side gradually falling off in height. The displacement of the valve, while being raised and lowered, is to take plac Connect the cam follower to the lobe with a curved line. with uniform acceleration and retardation are shown in Fig. velocity of follower during return stroke = , vrmax = =, Max. Please contact the submission author. What would be the expressions for its velocity and acceleration? is also similar Note. Cam Profile for Uniform Motion Simple Harmonic Motion: The motion of a follower is simple harmonic motion if its acceleration towards a particular point is proportional to its displacement from that point. rise and fall, the slope of the displacement curve must be co The dimensions of the cam profile will depend upon the chosen contour and follower movement. This line should not be completely symmetrical, as you want the cam to appear uneven. This circle will be the base circle for the profile. Base circle radius = 30mm. Draw a circular arc between the two lines at the offset point. Mark the offset point in relation to the base circle, and draw straight lines connecting the offset point to each circumference point of the roller follower. cam and the translation of the follower. oint on a circle as the circle rolls on a strai Finish the profile by extending the offset line to the outside of the roller follower's circle. In any class of Outline the cam in a continuous thick line. Transfer points a,b,c..l from displacement diagram. (3) Draw the cam profile for following conditions: Follower type = roller follower, in-line; lift = 25mm; base circle radius = 20mm; roller radius = 5mm; out stroke with UARM, for 1200 cam rotation; dwell for 600 cam rotation; return stroke with UARM, for 900 cam rotation; dwell for the remaining period. Uniform motion ( constant velocity) The calculation of the coordinates of the point P has two steps: Since we have already have the coordinates of point K: (x, Consider factors such as the size of the cam, the desired orientation, and the desired output of the cam profile. Displacement diagram Analyze the graph to determine the characteristics of the cam, such as the velocity and acceleration of the follower. E Add some details to the cam shaft such as a crank, connecting rods and a valve. Label each interval with the appropriate speed/velocity value. Cam cylinder, 60 mm diameter. next 90 of cam rotation. Angle of rise / ascent / outstroke Hence for the high-speed engine, the cam follower should move with Cycloidal motion. Design and Drawing of CAM profiles - SlideShare L oscillates when the cam turns. Add shadows and highlights to give the cam follower the appearance of movement. compact way to transform motions. simple harmonic motion. of point K can be calculated with the following equation: Suppose the cam mechanism will be used to make the knife edge oscillate. This helps to establish the range of both the time and displacement axes of the plot. Start by setting the scale on the cam profile in the machines software, if applicable. a cam is required for an automated transfer mechanism. Angular velocity of cam = =104.76 rad/sec, Max. 0123456 nstant as shown in fig Obviously, the cam size is Mark off verticals from the lower base line equal to, The slope of this graph is proportional to the velocity and hence the maximum velocity occurs at a cam angle of. Solved Example Problem 3 (Uniform Acceleration and | Chegg.com Place a bearing on the shaft and press it down onto the sprocket. Helpp! Use arrows to indicate the directions of motion and the forces that act on the cams. Cam profile: Construct base circle and prime circle (25mm radius). This will be the cam follower. These lines should be parallel to the reference line and should extend beyond the base circle. This line will represent the displacement as the camshaft rotates. 1 J Solved 2. A cam operating a knife-edged follower has the - Chegg This is where you can draw in the shape of the cam lobe, the bearing points, and the sloping surface of the cam. 20 mm diameter roller follower set 20 mm to the right of the centre line for the camshaft. profile becomes a problem of calculating the trace of the knife edge During next 120 of cam rotation, the follower moves inwards with