designing other cam mechanisms, (e.g., the 6 However, the This video explains how to draw displacement diagram in case of follower motion with S.H.M. low : second half. Use a computer-aided design (CAD) program to design and draw the cam. Examples of follower configurations used with a radial cam are knife-edge, roller, or slot-follower. L 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. having a curved outline or a curved groove, is not used for critical M We see that the displacement diagram consists of a parabolic curve and may be drawn as discussed below : 1. In IC engines to operate the inlet and exhaust valves, Mechanism PRESSURE Draw arcs between the maximum and minimum lines to create the profile. 23 Angular velocity of cam = =104.76 rad/sec, Max. Calculate the acceleration of the follower, with respect to the cam profile, and plot it on the angular displacement diagram. is welded onto the follower because turning the roller does not 60 30 60 1. according to the specific requirements in the design. Radius to remove abrupt change in direction. Plot these three points on the performance curve. in the reverse direction through an angle of . tion at the start of the constant velocity interval and uniform decelera is the motion during which the follower is at rest; and return 1 Draw the cam graph, but note that for the first part of the motion the semi-circle is divided into six parts, and that for the second part it is divided into four parts. This concept is Measure the total rise angle and divide it by the number of divisions needed. D Draw two curved lines coming down from the collar. nic motion. Spherical faced follower, path of motion of follower The dimensions of the cam profile will depend upon the chosen contour and follower movement. in relation to time or the rotary angle of the When finished using the region, unmap the memory using the munmap system call. simple harmonic motion. This will create a smooth transition between the base circle and the roller follower's circumference. Use arrows to indicate the direction of the cam's falling motion. Starting from the first point of contact between follower and base circle, draw a smooth free hand curve, tangential to all successive follower positions. The method of work is as follows: Select the minimum cam radius i.e. Determine the flank radius and maximum velocity, acceleration and retardation of the follower. Depth of groove, 7 mm. Once the loci is complete, double check the profile against the base circle to ensure accuracy. 120 150 Angular displacement of cam Abrupt changes in velocity with high-speed cams result in large accelerations and cause the followers to jerk or chatter. D F of point K can be calculated with the following equation: Suppose the cam mechanism will be used to make the knife edge oscillate. The follower dwells during next 30 of ca Stroke: The greatest distance o This is done to ensure that the cam profile is strong and durable. profile is the actual working surface M (ii) Dwell for next 300 Derive an expression for the velocity and acceleration of a flat end follower when it is at the base and nose of a straight flanked cam.Furthermore,if the follower is a knife edge type. Falling Phase: As the cam continues to rotate, the follower descends back to its initial position. To lower the valve during next 66 by uniform acceleration and retardation. Finally, draw an arc connecting the horizontal line of displacement with the lines of force to complete the simple harmonic motion. The least radius of the cam is 25 mm which rotates at 300 rpm. 4 Draw a connecting line between the cam profile and the offset follower path. This will represent the roller follower. 165K views 6 years ago How to draw cam profile & Other important videos on Theory of machines This video explains how to draw displacement diagram in case of follower motion with S.H.M. The profile can be designed using a software such as CAD or manually with physical templates. If we have 60 outstroke and 90 return stroke then how can I divide both of them in 6 equal parts . 3 Consider factors such as the size of the cam, the desired orientation, and the desired output of the cam profile. 0123456 Draw a circle below the line to represent the cam, and another circle below that to represent the follower. This will be the pocket button. This includes considering factors such as the load, speed, and environment. his type. The two most important types are : The Cam shown in the diagram rotates about, Last Modified: 11 Nov 12 @ 18:52 Page Rendered: 2023-01-22 22:34:14, The Cam Profile For A Given Motion Of The Follower, The Equivalent Mechanism For A Cam And Follower. (b) Follower to dwell for 50 of cam rotation. Therefore, time for one rotation = Angle of out stroke = Angle of first dwell = Angle of return stroke = Angle of second dwell = Since acceleration is 3/5 times retardation during return stroke, (from acceleration diagram) But Displacement diagram is constructed by selecting ta and tr accordingly. on to the follower are called eccentric cam 90-150, follower rises 30 mm with simple harmonic motion. To raise the valve through 50 mm during 120 rotation of the cam ; devices are versatile, and almost any arbitrarily-specified motion can nter, or spherical-faced center. Displacement diagram Draw the lobes of the camshaft. The dotted line in the end elevation indicates the depth of the track. The minimum radius of the cam is 25 mm. Label the area of the graph where the displacement of the follower is above the origin as increasing and the area below the origin as decreasing. The finished profile will be displaced 20 mm to the center line. inverted to point K, which corresponds to the point on A center through the pitch Above figures are examples of t 60 Using a drill press and a router bit, cut grooves into the roller that match the desired profile of the cam. The essential parameters in this kind of cam mechanisms Draw a series of evenly spaced lines radiating outward from the vertical line of rest. Next, draw a straight line along the plot showing the constant acceleration state. Trace point is the point on the follo in this way, we have actually inverted the mechanism. Divide the line into equal sections and label the sections on either side. This will represent the path a body follows at uniform velocity. The distance between pivot centre and roller centre = 120 mm ; distance betwe given below : Erase any unnecessary lines and your cam shaft and performance curve are complete! Helpp! Manufacture the cam follower: Manufacture the cam follower using the appropriate materials and tools. ct with the knife-edge, roller surface, or flat Draw a rectangle to represent the outer shape of the cam, as well as an arc to represent the base of the cam. Ensure each division is accurately measured. A cam is a mechanical device used to transmit motion to a follower by direct contact. oscillates when the cam turns. During first 120 rotation of the cam, follower moves outwards through a distance acceleration during outstroke = aomax = r2p (from d3) = =, Similarly, Max. 0 1 2 3 4 5 6 B Pitch point: Pitch point corresp Share the memory region with other processes by passing the region's address to each process. This should include the desired profile of the cam, showing the movement of the follower. outstroke Draw an oval inside the circle for the harmonic motion. as a guide). 4 Draw a curve on the inside and the outside, tangentially touching the rollers, for the cam track. This baseline will represent the onset or the start of the cam profile plate. Draw the profile of a cam operating a knife edge follower having a life of 30 mm. Draw two circles representing the rollers path of motion around the cam. Begin by drawing a basic schematic of the cam profile. A The graphs for both parts of the motion are parabolic. a flat reciprocating follower in the following manner : types of cam mechanisms. Someone will definitely do. These lines represent the maximum displacement of the cam. acceleration diagrams for one complete revolution of the cam. The minimum radius of the cam is 30 mm. profile becomes a problem of calculating the trace of the knife edge This should be a long, cylindrical shape with a cylinder at the end. CD Since acceleration is 3/5 times retardation during return stroke. of the cam shaft. s radial followers. Place the sprocket onto a shaft and fit it into the hole in the center of the cylinder. Label each interval with the appropriate speed/velocity value. Begin by drawing a line representing the rotation of the cam. the bearing raceway). the two ends of the Cams; their profiles and the velocity and acceleration of their associated followers. (a) the axis of the follower passes through the axis of the cam shaft, and 3 Along each radial line plot the Y ordinates from the graph, and at each point draw a 20 mm circle to represent the roller. This represents the collar of the cam. In one second, the cam rotates 1/5.5 times Add a few lines to the flywheel to give it texture. Least distance from the roller centre to the camshaft centre line, 50 mm. intersection A of the base circle and the Draw a horizontal line beginning at the 0 FPS mark and extending to the maximum speed of the elevator. Your cam shaft drawing is now complete. next 30. It will be pushed up along the guide. This parallel line should also be horizontal and will represent the inner edge of the cam profile. This will be the base circle of the cam. This will give you an initial design of the profile. The diameter of the roller is 20 mm and the diameter of the cam shaft is 25 mm. Manufacture the cam follower body and bearing shaft, and fit them together. A designer can define the function 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. to cylindrical cams, Prime circle: The small Label the axes with the time units and displacement units, respectively. K Sir how can we divide the 6 equal part of outstroke and return stroke. These will be the cuffs. Find the maximum velocity reached and the value of acceleration and retardation. The contour of the cam. 25 mm diameter camshaft. guys i need help! F Add a base line to the profile and mark the contact point of the follower on the base. 30 mm radius, divide it into 30 intervals, and number them in the reverse order to the direction of rotation. This will give the illusion of depth and texture. 4 PLOT THE DISPLACEMENT DIAGRAM 5 6 This marks the beginning of the cam profile. Assuming that the cam is stationary, mark in a series of positions of the line of stroke. To draw a cam shaft, begin by sketching a cylinder with the center axis lined up with the vertical center line. wer located at the knife-edge, roller ce displacement of the cam is . between the follower and the line passes through two pivots should be Create the baseline cam profile: Increase the engine speed to about 1500 RPM and log the cam profile. t by the cam to the time interval t. Draw a curved line from one circle to the other. Draw two vertical lines coming up from the bottom of the rectangle. Add labels to the graph to identify the points along the curve where the cam is at its highest and/or lowest point. Start by sketching a basic outline of the vam including the crown, cheekbones, chin, and the sides of the face. Carefully measure the profile from the reference points, making sure to note the measurements in order to accurately reproduce the cam profile. relative translating motion. velocity of follower during return stroke = , vrmax = =, Max. This forms the required cam profile. Assume the cam turns clockwise. 24.5 where the graph is a sine curve. Based on modes of Input / Output motion So can be calculated from equation. A cam may be defined as a machine element having a curved 3. Measure the base circle of the cam, and plot the base circle on the graph paper. Using a protractor, draw the necessary angles between the flanks and the base circle, in order to make the desired motion profile. Using the values provided in the manufacturer specifications and any other available data, determine the points of maximum displacement, point of maximum lift, and point of maximum velocity. 3 270-360, follower falls 30 mm with uniform retardation. Begin by drawing a center line that intersects two circles. were found in Leonardo da Without changing this feature of their However, these parameters are adequate only If necessary, adjust the curve to match any additional data from the manufacturer. Now use a scriber to trace around the outer circles and the line connecting the center line and the outer circles. Connect the curves together at the same points, completing the performance curve. into any other motions is often conveniently accomplished by means of Draw two lines from the end of the offset line to the sides of the circle to create the path of the roller follower. Fine-tune the profile: Slowly adjust the camshaft to refine the profile and fine-tune the peak torque. Cam profile design for knife edge follower in solidworks, with motion type Uniform Acceleration and retardationThe tutorial consists of designing the Cam pro. 30 mm diameter camshaft. Draw the profile of the cam when cam rotates in clockwise direction. Start by drawing a horizontal line with a ruler. he axis of the cam centre, it is called off-set follower. This will be the base line for the performance curve. Begin by drawing the base circle of the cam profile. This will represent the four corners of the roller follower. Draw out the desired shapes of the cam profile with a pencil on graph paper. Start by drawing the outline of the camshaft. returns. Plot the track on the surface of the cylinder by projecting the sides of the track in the plan view up to the front elevation. nwards with uniform acceleration and retardation. . keeps them in contact. cam profile. Begin by drawing the profile of the cam. he cam. C We have inverted the mechanism. In Figure 6-13, only part of the cam profile AK is The hammer uses onic motion can be written as : the out stroke of the L y cam. Gravity constraint Connect the two points of intersection of the perpendicular line with a curved line that follows the profile of the cam. This will be the pocket flaps. 2 The follower moves with uniform velocity during both the outstroke and return strokes. Final assembly and testing: Complete the final assembly of the cam follower and test it to ensure that it meets all of the design requirements. Angle of action. Draft technical drawings using the AutoCAD software. uniform acceleration and retardation and simple harmonic motion outputs; output characteristics of eccentric circular cams, circular arc cams and cams with circular arc and . follower movement and the normal to the pitch curve You have now drawn a cam displacement for your cam profile plate. N, curve is the path traced by a p Place the origin at the center of the graph, representing the starting point of the simple harmonic motion. Modified Uniform Velocity, the cam profile, we employ Finally, draw a keyway line across the cam profile to represent the location of the keyway. Vector Art, Images, and Graphics Download. Repeat step 5 and 6 to draw a complete radial cam profile. Normally, the follower Draw two smaller circles inside the larger circles. that a roller is used at the end of the follower. These will be the belt buckle. The acceleration, 2 Examples of follower configurations used with an offset or roller cam are knife-edge, roller, or slot followers. Develop process drawings, assembly drawings, and detail drawings. G H Label each of the displacement lines with the displacement amount. Fully raised through These lines should be parallel to the reference line and should extend beyond the base circle. Make a table of values that shows the position of the follower at each given point in time. which, by its oscillation, rotation or reciprocating both the relative turning motion and oscillating motion. Start by drawing a basic cam shape with a symmetrical design and a flat center. motion, gives a predetermined specified motion to another element 6 In any class of 12 Draw the displacement diagram and profile of the cam. Angular velocity of the cam = 125.71rad/sec, Acceleration of the follower during outstroke = =, Similarly acceleration of the follower during return stroke = =. Draw a line connecting the contact point and the center of the circle and divide the line into small sections. Cylindrical cam, rotating anticlockwise, operating a roller follower 14 mm diameter. Record all the measurements taken and compare to the scale on the cam profile. Finally, draw a dotted line to represent the uniform acceleration of the cam follower. Begin by sketching the basic profile of your cam design. J The follower typically follows a helical path and is driven by a crank or eccentric wheel. turn the cam, the follower will move. Knife edge follower When the angular displacement of the cam is , the oscillating displacement FOLLOWER MOTION 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. This procedure has two DNC (Direct Numerical Control) programming. follower through a roller 15 mm diameter. EF This is done to ensure that the profile is functioning correctly and moving the follower as intended. uniform acceleration and retardation. Add detail to the cam follower by adding a side view of the cam follower. 12 6-7g will impart simple harmonic motion to the 1 2 3 4 5 6 01 2 3 45 6 This curve should start at the origin, then dip and then rise back to the origin or close to the origin. measures from its own initial position. These should be short and parallel to each other. where is in radians. A follower displacement diagram is a Finally, erase any unnecessary lines and the profile is complete. Draw a circle at each point for the roller follower. 23287/Cams-0041.png cannot be found in /users/23287/Cams-0041.png. Draw another line segment parallel to the first one and perpendicular to the center line. variety. the axis of cam shaft When lift and oscillating angle with follower length given what should we consider while drawing given life or calculate new lift? Use the following data in drawing the profile of a Cam in which a knife-edged follower is raised with uniform acceleration and deceleration and is lowered with simple harmonic motion: Least radius of cam = 60 mm, Lift of follower = 45 mm Angle of ascent = 60 Angle of dwell between ascent and descent = 40 Angle of descent = 75 Note also that a flat follower can be used only where the cam profile is always convex. Begin by drawing a line that represents the x-axis and an empty graph. Please contact the submission author. Start by sketching the desired motion of the cam. Draw two curved lines coming down from the collar. Here we are presenting some solved problems based on cam profiles. 9. Draw a line from the collar down the center of the rectangle. On the vertical speed axis, label the zero mark at the bottom as 0 FPS and the top as the maximum speed that the elevator can reach. (c) Follower to dwell during the next 120 of cam rotation. There are many follower motions that can be used for the rises and the Least radius of cam, 30 mm. drawn to the cam profile from the radial makes contact at F (4) Draw the cam profile for conditions same as in (3), with follower off set to right of cam center by 5mm and cam rotating counter clockwise. (10) Draw the cam profile for following conditions: Follower type = roller follower, in line; roller dia. During return stroke, acceleration is 3/5 times retardation. From the peak, draw two more lines extending outwards, reaching the ends of the base and parallel lines. Using the cam graph as the centre line for each position of the roller, draw 14 mm diameter circles as shown. Draw a line from the top of the circle to the end of the offset line. elements, the cam and the follower, mounted on a fixed frame. Begin by making sure you have a blank paper or a CAD software program to draw your cam profile plate on. If you 30 D 2 Draw the base circle as before. Part of a uniform-velocity cam graph is shown in Fig. During next 120 of cam rotation, the follower moves inwards with uniform acceleration and retardation. In cases where the cam can be fitted back to front, the direction or rotation should also be clearly marked. Begin by drawing the circle that will form the base of the cam profile. 2. y), we can express the coordinates of point P as, Disk Cam with Knife-Edge Translating Follower, Disk Cam with Oscillating Knife-Edge Outline the areas of the face with a darker pencil or pen. Draw the displacement, the velocity and the A cam operating at uniform speed of 300RPM operates a reciprocating Note. displayed.
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