Modelling concave globoidal cam with indexing turret. Globoidal indexing cam mechanism is the spatial indexing mechanism of high speed, high precision and widely used in modern machine and automatic production line. Geometry design of globoidal cams with generalized meshing. Design and machining of globoidal index cams journal of. According to the follower mechanism, they try to design the globoidal contour parameters that can achieve the desired law of motion. Such a mechanism with six cylindrical rollers is shown in fig. One of the attractive features is that the dynamic char acteristics of a globoidal index cam can be controlled through the selection of its follower motion curve. Pdf cam design projects in an advanced cad course for. The cam rollers running in the cam followers are precision guided along the cam by the hardened and polished cam track. When we design the motion for the input camshaft, we also add a gearing fb with a ratio of 4 this is how the model looks.
On the basis of theoretical study, the paper using structured program design method and visual basic 6. For the love of physics walter lewin may 16, 2011 duration. A design example is presented for demonstrating procedures of surface generating of the globoidal cam. It will reduce time spent on the drawing board and increase productivity and machine accuracy. Consideration of manufacturing parameters in the design of grooved globoidal cam indexing mechanisms d m tsay and h c ho proceedings of the institution of mechanical engineers, part c.
Each cad and any associated text, image or data is in no way sponsored by or affiliated with any company, organization or realworld item, product, or good it may purport to portray. The aim of this paper is to present the methodology of design and analysis of radial and globoidal cam of tool changing mechanism of atc used in vmc with accurate motion by using dynacam 10 software. The systematic design approach proposed for a globoidal cam mechanism with an intermittent variable speed is to improve its performance, to upgrade effectively. The result of this work enhances the usefulness and convenience of the analysis of geometric properties for roller gear cams with hyperboloid rollers. Rothbart allows engineers and technicians to utilize cutting edge design tools. In general, engineers design the globoidal cam by the handbook. Emphasizing computeraided design and manufacturing techniques, as well as sophisticated numerical control methods, cam design handbook by harold a. Under the column cad a zipped file incuding dxfdwg and tifdrawings as well as step3dmodels can be downloaded. The translational or rotational displacement of the follower is a function of the rotary angle of the cam.
Reconstruction of globoidal cam follower motion curve. Pdf model and simulation of globoidal cam mechanisms. Cams with translating and oscillating followers, globoidal. Such a type of cam is preferred when the requirements are low wear, low noise, better control of the follower, high speed, high dynamic loads, etc. Three models with different modelling methods are made from the same input data. An application of geodesics to the calculation of the rib. Globoidal cams are a common, but still very special design of cam gears. Motioncurve synthesis and geometric design of globoidal cam. Naturally, you have to stare that inside mechanism, where it does the. Product catalogue cam mechanisms for industrial automation. The manual cam layout method described in this section is used primarily for informa tion.
With globoidal indexing cam mechanism as the object of study, this paper introduces its operating principle, analyzes and calculates its main motion parameters. Hi all, what im trying to do is the same cam you can see in this youtube video. A roller is in a cam groovetrack, or two rollers are braced across a cam rib, or two cam flanks. Design of torque balancing cams for globoidal cam indexing. Design and analysis of radial and globoidal cam of tool changing.
Based on the differential geometry and conjugate theory, the machined surface and the surface deviation of a globoidal cam are derived with the help of a vs software. The axis of the globoidal cam is perpendicular to the turret axis. A globoidal cam mechanism is composed of a globoidal cam and a turret with rollers. Modeling a globoidal cam hi all, what im trying to do is the same cam you can see in this youtube video.
The input data include some basic dimensions of the globoidal cam system and a table of angular input and output displacements of the cam and the follower. Equipped with bevel gear or worm geared motors from wellknown manufacturers, our gearboxes represent outstanding drive systems. Pdf model and simulation of globoidal cam mechanisms with. The result of this work is necessary for the computeraided design and manufacturing of roller gear cams for industrial applications. The servo roller positioner grants reliability, high dynamic performance, flexibility, smoothness of motion and efficiency. Mechdesigner will calculate the globoidal cam profile to machine accuracy no. But the contour surface of globoidal cam is nondevelopable curved surface, it cannot be described by mathematical formulation. But the working profile of the globoidal indexing cam mechanism is not fair for the space curved surface and it is difficult to model. The camfollower is rigidly attached to the follower arm. The contact and the shape of the cam is influenced by the shape of the camfollower. When rotating the cam, the cam track and the cam rollers generate a predefined smooth movement of the output shaft. Here the drawings of our globoidal cam gear boxes can be downloaded in several formats. Journal of mechanical engineering science 2001 215. In mechanism environment, ive made the trace curves of some points of.
Motioncurve synthesis and geometric design of globoidal. The camfollower is in continuous contact with the camprofile. Modeling concave globoidal cam with indexing turret. Our product range consists of globoidal cam gears, parallel cam gears, globoid index tables, cylindrical index tables, cylindrical ring tables and placers. The globoidal cam and output turret with integrated rollers are a preloaded system that delivers zero backlash for superior accuracy, stiffness and long term durability. It is also necessary for the task of computeraided design and manufacturing of roller gear cams for industrial applications, e. From the machining point of view of the globoidal cam by an end mill, the side surface geometry can be easily defined as the swept surface by the tool path. Consideration of manufacturing parameters in the design of. In the working process, the rollers are driven by the. Mechdesigner will calculate the globoidal cam profile to machine accuracy no approximations. Design and analysis of cylindrical cam with roller follower rotary indexing table by panchal vikram jayantilal enrollment no.
Cam design software is fully integrated into mechdesigner you can model then let mechdesigner calculate the cam coordinates of just about every cam type, including. Design and machining of globoidal index cams citeseerx. Chen roller guide design and manufacturing for spatial cylindrical cams t. The globoidal cam rotates about its axis driving a roller follower. Abstractthis paper describes a computeraided design for design of the concave globoidal cam with cylindrical rollers and swinging follower. This analysis plays a significant role in the performance determination of the cam as well as the atc of cnc machines. The parametric design and simulation for globoidal. The traditional design method requires a great deal of calculation, and the design process is. Design of cam still needs to be improved for better performance of mechanical systems.
Mechdesigner models globoidal cams with complete accuracy globoidal cams combine great strength and stiffness with compactness. This cylindrical cam tutorial there is a cylindrical cam tool directly in later releases of inventor along with the previously posted link might get you started to a solution. Tolerance analysis and allocation of special machine tool. In practice, they are used almost exclusively in globoidal indexers, which are a standard. Globoidal cam indexers features flange or shaft output, universal mounting optional thru hole, optional double extended output. The solid model of the globoidal cam with tapered ribs is shown in fig. Camfields globoidal cam indexers are robust, versatile units suitable for a vide variety of application. The input data are angular input and output displacements of the cam and the follower and some other geometrical parameters of the globoidal cam mechanism. The first step when design cam is to define the mathematical functions to be used to define the motion of the follower. Pdf globoidal cam mechanisms with oscillating and dual stopping followers are. The camfollower can have a number of different shapes, each with advantages and disadvantages. The motion requirements, listed below, are commonly used in cam profile design. Globoidal cams are you using inventor 10 or are you really using inventor 2010.
Zero backlash roller gear cam mechanism innovative roller gear design provides exceptionally smooth motion performance. Globoidal cams combine great strength and stiffness with compactness. Design and analysis of radial and globoidal cam of tool. A designer can define the function according to the specific requirements in the design. This paper describes a computeraided design for design of the concave globoidal cam with cylindrical rollers and indexing turret. Four models with different modeling methods are made from the same input data. Geometry design of roller gear cams with hyperboloid rollers. This paper describes a computeraided design for design of the concave globoidal cam with cylindrical rollers and indexing turret follower. A design procedure for increasing the performance of an intermittent globoidal cam mechanism is presented. This design of cam can help to prepare geometric drawings and model of cam which used.
Download limit exceeded you have exceeded your daily download allowance. The cam design and the preload between cam and output turret allows for a high rigid, precise and backlash free unit in any position. Request pdf design of torque balancing cams for globoidal cam indexing mechanisms a technique for designing torque balancing cam tbc systems that. Motion curve in cam mechanism, a cam is the mechanical element used to drive another element, referred follower, through a specified yuan l. Most of these cam gears can also be designed as pendulum gear. The proposed procedure is based on the synthesis of rollerfollower turret motions at two different speeds to lower the inertia effect caused by the startstop behaviour of the intermittent mechanism. A simple, yet useful approach to the geometry design and machining of globoidal index cams and rollerfollower turrets is developed. Also the measure feature checks that there arent compenetration as i showed in the video into the ppt file. Design of globoidal indexing cam mechanism cad system. Globoidal cams a globoidal cam can have two types of surfaces, convex or concave. Globoidal cam in indexing machine cmb engineering, 2007. In order to produce a special machine tool for manufacturing highquality globoidal cams, this paper presents a systematic approach for tolerance analysis and tolerance allocation for the special machine tool. A globoidal cam with an indexable turret and roller follower rotating in an enclosed track has been evaluated in our analysis.
Design and drawing of cam profiles linkedin slideshare. The computeraided design cad files and all associated content posted to this website are created, uploaded, managed and owned by third party users. I have the motion law i want to assign to the rotation of the tower in function of the rotation of the cam. In a variety of designs, including stud and yoke types, with specialized options. The basic curves and splines used to design the cam profile by various researchers in past two decades.
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