Design And Dynamic Simulation Of Cam Automatic Feeding System For Assembled Camshaft

China is currently undergoing a rapid development resulting in improvement in living standard, which reversely stimulate demand for higher life quality. Under such context, automobiles, as a means of transport become accessible to more families. Unfortunately, due to the asynchronous development in spare parts and vehicle manufacture techniques, a large number of spare parts are imported. Therefore, accelerating spare parts industry, setting up a supporting system of spare parts, encouraging innovation, speeding up the structural upgrading of automobiles, and facilitating sustainable development of motor industry are major objectives put forward in eleventh five-year plan.Engines as motion source directly impact automobiles'performance. So is camshaft, a key part in engines. Modem camshaft processing technologies mainly include welding,sintering, and mechanism jointing, of which the last one is the most popular one. Meanwhile, knurling in mechanism jointing based on knurling cutters causes minute convex on the surface and excessive assembly with cam so that they can be incorporated together. This method is efficiently productive and low cost.Leading camshaft assembly technology, knurling technique developed by Roll forging Institute of Jilin University enjoys extensive popularity in China. However, due to semi-automatic production, the feeding process is operated manually, therefore, unable to compete with automatic production in foreign countries. The design aimed at fulfill the task of cam feeding by mechanic system, puts unprocessed parts in vibratory feeder which selects and shapes and transports the cam to the clamp according to the design requirements, so that the whole feeding task is completed. Taking advantage of manipulator reduces workforce, gets rid of the harm caused by misoperation, and stablizes system.1. Feeding planThe procedure is to accurately transport a pile of cams through a feeding system to the position of a given manipulator. It breaks down into the following paradigmz: design a round vibratory feeder which distributes parts into a line through location restriction device and modifies the stacked parts into single layer through pressure restriction device. Then parts will be transported from the bottom of the feeder to the exit at the top where an intelligent identification device is installed to distinguish those products that are inconsistent with the design requirements and drive them to the bottom part to wait for the refeeding process. Quality parts will enter straight line vibratory feeder and move forward till the end of the feeder where an initial directional clamp is installed to locate the cams in order to facilitate the crawling task of manipulators.2 .Design of manipulatorThe paper introduced and compares two pneumatic manipulator of varied operation modes: straight line manipulator and rotation manipulator in an attempt to identify the better design as the final product to further develop.In order to fulfill six steps in parts transportation: crawling, lifting, transporting, direction modifying, positioning, and releasing, the manipulator must have hand movements, wrist movements, forearm movements, and upperarm movements. Rotation manipulator in this paper is consisted of hand which is operated by HGD pneumatic hand of three support, wrist which is operated by DQRD 90°rotation cylinder, forearm which is operated by DNSU liner cylinder, beam, shoulder which is operated by DQRD 180°rotation cylinder, and base. Straight line manipulator is consisted of hand, wrist, forearm, beam and base, of which hand, wrist are operated by same cylinder motion as rotation manipulator, yet , forearm is operated by SLT non-track cylinder and beam by DNGL cylinder as horizontal motion cylinder to transport cams. Four types of cylinders work in coordination to finish the task.3 .Dummy machine simulationIn this paper, two key positions were experienceing dynamics simulation, which verifies the manipulator's accessibility and precision of initial location.Dummy machine simulation is applied in initial location of cams in directional clamp. Besides, dynamics simulation is applied in response to cylinder's asynchronous movements and slight mistakes resulting in four different possibilities. The results show that the directional clamp are able to finish location task. Through assembly simulation, certain intervention issues that are probably ignored in the design process are addressed to. For instance, portal frame in assembly process will intervene with the bottom plate of directional clamp. In response to this problem, this paper puts forward the modification plan that switches portal frame with single arm. In terms of dynamics simulation, intervention problems take place between line cylinder and buffer. By comparing manipulator's hand speed and accelerating speed in two plans, we are able to identify that straight line manipulator is slower than rotation manipulator in hand speed and accelerating rate, while the former's motion is more smooth and stable which is suitable to be the end product.In sum, the design is going to underpin the creation of a complete production line for assembled camshaft processing.But this paper introduced the elementary design of automatic feeding by assembled camshaft which still needs further modification in structure and techniques before mass production. With the development in overall automobile industry, it is reasonable to conclude that assembled camshaft technology as a product featuring productiviy, speed, quality, and low cost will have a bright prospect.