Advance Products, Inc. produces automation equipment for the die casting industry with a particular emphasis on automatic die spray and metal ladling systems. Recently, the company has dramatically improved the capacity, efficiency and durability of our equipment by simulating its operation using DE/MEC mechanisms analysis software from Desktop Engineering Int'l Inc., Woodcliff Lake, New Jersey. The software makes it possible to closely analyze the linkage motion of the equipment as it moves through the positions required to do its work. During initial equipment design stages, changes can be made to any desired design parameter after which an analysis is run to determine the impact of the change on performance of the system. Using an iterative process, Advance Products engineers have been able to smooth out motion paths and thus reduce cycle time and improve production output by avoiding abrupt motions, moving efficiently and improving the life of the equipment through the bearing analysis capabilities of DE/MEC. Other design changes made it possible to significantly increase the carrying capacity of the ladling system without changing any of the bearings or other major components. The productivity of a related reciprocating sprayer was increased by altering the mechanism to maintain the device in a horizontal plane thus reducing the amount by which the die needs to be opened. This also increased the unit's serviceability since it was more accessible when mounted on the floor. In all cases, motor torque requirements throughout a work cycle permitted a more thorough evaluation of motor size requirements for their equipment.

Advance Products customers include suppliers to the automotive industry as well as companies producing components used in lawn and garden equipment, electric motors, washing machines and other products. The company uses servo drives in all of our equipment, which provide inherent higher reliability than brush-type DC motors, which are commonly used in the industry.

In the past, it was difficult to get an accurate picture of the effects of design changes without hours of calculations and/or building a prototype, which led to very conservative engineering practices. Then, about a year ago, I saw an article in a trade journal that explained how DE/MEC software was used to optimize a coining press and I realized that many of the same issues involved in that project applied to our products as well. We purchased the software and began modeling one of our typical linkage mechanisms. The basic advantage of the software package is that it allows us to alter various elements of a linkage and visualize the performance of the mechanism. One form of output produced by the program is an animation that follows a particular linkage point throughout the cycle of motion. We were able to redesign several mechanisms to smooth out their paths and also make them more direct, which reduces the possibility of abrupt moves and also cuts the cycle time.

The ability to visualize the performance of our mechanisms before they are built provides a number of other advantages. Once the linkage is complete, the program allows the user to add real world loads and calculate bearing loads and torque for each pivot point. We have generally found that the bearing loadings we were using were considerably larger than necessary. By adjusting the strength of several minor components, we were able to increase the rated capacity of our ladling equipment by 50% thus making it possible to substantially increase shot weight without raising the costs of the equipment significantly. The program also has made it possible to determine the optimum size of motors used to drive each axis, where in the past we were forced to rely upon the best-guess approach.

For example, in several cases, prospects for our systems have provided their plant layouts in DXF format. We have imported their data into DE/MEC and laid out our equipment on top of it. This simplified the task of insuring proper clearances and also provided an excellent method of demonstrating our design to our customer using information they determined as being accurate. After the job was complete, we used these same models as support drawings in our equipment manuals.

Aside from helping us improve our designs, the software has also made it a lot easier to demonstrate our designs' features. In some cases, we have modeled our competitors' products and superimposed the animation of their systems' operation over our own system. In this way, the performance gains we have achieved can clearly be seen on the screen. For example, the animation feature shows how our automatic ladler product runs more smoothly and presents less risk of dipping the ladle pivot into the metal. Superimposing the spray animation against our competitors highlights the fact that ours operates in a true horizontal plane. Another benefit of the package is that it makes it very simple to generate a model, perform the analysis and view the results in animated, tabular or graphical format. The only time I had a problem -- exporting to Excel -- technical service talked me through it one mouse click at a time. What we were trying to do was compare the bearing loads of several mechanism variations and show then in a graphical format for emphasis and ease of understanding.

The key capability of Advanced Products, Inc. automatic ladlers is moving a precise amount of molten metal from the furnace to the die casting area. The process begins for a ladler when its cup is dipped into the pot of molten metal in the furnace. The filled ladle is then raised slightly above the pot to pour out excess material back into the pot so that the precise shot amount remains. The purpose is to minimize energy consumption by reducing the amount of metal, which later needs to be trimmed off and reheated. The ladle cup is then rotated back to the level position and carried to a position where the cup will then be rotated to pour the metal into the shot sleeve which feeds the die. Two axes of servo are used to control the ladling device. One axis rotates the cup and the other

maintains the proper position on the linkage. Use of DE/MEC has allowed linkage evaluation to determine motor sizes, bearing loads throughout a cycle using various shot weights, cup path smoothing to reduce spillage of the molten metal, and use of the results in the actual equipment manuals.

Advanced Products has also used these techniques in the design of a complementary product, which sprays a release agent on the die surface to prevent sticking. The critical design issue on these reciprocating sprayers is to provide the straightest possible path for the sprayer as it moves into the die area so that the die can be opened as little as possible. The sprayer operates in a horizontal plane and has several different nozzles, each of which is designed to spray a specific portion of the die. Using DE/MEC, we were able to produce a very smooth motion curve. This reduces the amount by which the die has to be opened and thus reduces the cycle time of our customer's operation. We were also able to reduce motor torque requirements using the optimization features of DE/MEC along with its ability to modify linkages and show all aspects of the modification. A high torque requirement on one particular part of the cycle had to be overcome and an optimization analysis was used to reduce it. This change further increased the life of the unit.

DE/MEC mechanism design software is a powerful and easy to use mechanism design, analysis, animation and optimization tool. Using Window 3.1 and a mouse, it can be used to model the most complex mechanisms on a desktop personal computer. It can also interface with CAD systems. Desktop Engineering Int'l is a software developer and distributor specializing in engineering applications based in Woodcliff Lake, New Jersey. The company's other products include The Desktop Engineer, the world's largest known database of solutions to engineering equations; and DE/CAASE, which provides a revolutionary method of organizing data so that it can be instantly accessed and managed according to the project from which it is being used. The company also has Desktop Engineering Technical Centers in England and Canada, with representatives throughout Eastern Asia and Europe. All Desktop Engineering Int'l products are available from authorized dealers located throughout the world.