A flexible clutch assembly line

A flexible clutch assembly line

by Matthew Gagliardi and Raymond J. Cipra

A proposed redesigned clutch assembly system has almost 65 fewer stations and one line versatile enough to handle four types of clutches

A recent study we conducted at Purdue University in West Lafayette, Ind., for a U.S. automaker was designed to develop a flexible assembly line for automatic-transmission clutches. The line would have to accommodate various clutches and parts, especially prototype parts, as well as minimize maintenance, manual stocking of parts, and shutdown times. To accomplish these goals, the designs of parts and assemblies would have to be changed.

This cross section of the forward clutch shows the suggested design changes, including the modified spring-pack cap and bonded seals

As a result of our study, the number of clutch parts can be reduced by 14 and the number of different models of parts by one. A proposed new assembly system means just 13 stations rather than 77, none of which requires manual operation. The old system has four specialized assembly lines, one for each type of clutch in an automatic transmission (forward, reverse, intermediate, and direct); the new system has one line flexible enough to handle any of the four clutches.

Components common to all clutches were identified and atypical parts were considered for combination or elimination. Next, the assembly process for the clutch assemblies was examined to note assembly motions and any special processes. In addition to looking at parts that could be shared or modified for sharing, our study determined that certain parts were not needed--their function could possibly be combined with that of another part. Parts were also examined to see how they were assembled and whether design changes would simplify assembly.

The proposed assembly sequence, which can be used for all four clutch types, needs to make only three major decisions, which depend on the type of clutch being built: whether a ball-check valve needs to be inserted in the cylinder, whether to install a wave spring or a support plate, and whether the clutch is the direct type, which needs to be turned over so that an intermediate clutch can be built for that assembly. The above was adapted from an article The full text of the article may be found in the June 1997 issue of Mechanical Engineering magazine. © 1997 ASME International. To obtain a copy of this issue, click here:

The above was adapted from an article by Matthew Gagliardi, a design engineer at Toyota Technical Center in Ann Arbor, Mich., who co-wrote it while he was a graduate assistant in the School of Mechanical Engineering at Purdue University in West Lafayette, Ind., and Raymond J. Cipra, an associate professor at Purdue's School of Mechanical Engineering. The article was adapted from a paper presented at the 1996 ASME International Mechanical Engineering Congress and Exhibition in Atlanta. The full text may be found in the June 1997 issue of Mechanical Engineering magazine. © 1997 ASME International.© To obtain a copy of this issue, click here.