New Ideas From An Old Hand

There were many new and exciting new products exhibited at IMTS in Chicago. As I mentioned last month, I planned to spend a good deal of time in the tooling, workholding and accessories pavilions after I had "kicked the tires" in the machine halls. I fully expected to uncover some new and beneficial ideas from some new small "up-starts." Surprise, surprise, the following information is indicative of the strides that many of the old timers are making to help us stay productive.

Troyke Mfg. Co. was founded in Cincinnati, Ohio, in 1939, to build manual rotary tables for the machine tool, defense and other manufacturing industries. Its product line has evolved over the past 61 years to include manual, cross slide, servo powered and tilting rotary tables. Troyke has always built special or custom rotary tables. Many of today's standard product lines were once special projects. Like the industry it serves, Troyke Mfg. has evolved from overhead belt machines and drawing boards to CNC machines and AutoCAD.

Although Troyke is constantly developing new products and production techniques, many of its vendors and customers date from the 1940s. Five years ago, Western Cutterheads of La Center, Kentucky, requested that Troyke quote a twin spindle tilting rotary table. The table was to be used on a Cincinnati Machine, Arrow 750, vertical spindle machining center to machine components for the new Hydro-lock tooling system that Western was introducing.

Hydro-lock is a tooling system used by the woodworking industry to make tooling to produce turned parts, for example stair spindles and porch posts. The part geometry required five-axis machine capability (four-axis contouring and M function tilt axis). Production quantity dictated a twin spindle to minimize cycle time.

The first approach utilized standard components. Two 6-inch diameter tables were mounted horizontally, in tandem, and co-planer to a sub plate. The sub plate was then supported at one end by a vertical 10-inch diameter rotary table and at the opposite end by an outboard bearing support. The assembly provided twin tandem tilting rotary tables and was rigid and accurate enough for the application. However, the assembly was too high and too long for the machine Z and X axis.

At the request of Western Cutterhead's Ken Anselm, Troyke designed and built a 10-inch diameter table that would have the above 6-inch prototype's geometry and rigidness while using less of the machine's X and Z axis envelope. This was accomplished by moving the worm gearing and breaking assembly to the bottom of the sub plate and mounting the rotary axis motor to the outboard end, concentric to the tilt axis table. A special drive shaft was mounted in roller bearings to drive the rotary axis wormshaft via a timing belt. The two rotary axis wormshafts were coupled end to end and rotated as one axis. Basically, the rotary axis servomotor runs through the center of the tilt axis.

Since installing the first TDL-10 in 1996, Western Cutterhead has installed three more Cincinnati Machine Arrow 750 machining centers, requiring Troyke TDL-10-2 tandem tilting rotary tables. Troyke has expanded the TDL series to include both single and tandem tables in 6.5-, 10-, 15-, 20- and 25-inch diameters.

Mike Ortman, Troyke's OEM sales manager says, "The TDL series is an excellent choice for milling applications requiring high torque and rigidity in single or dual tilting tables."

At IMTS 2000, Troyke introduced the "L" series of tilting rotary tables. A derivative of the TDL series, the L series features a single rotary axis base casting mounted directly to the face of the tilt axis table. Like the TDL series, the L series rotary axis servomotor is mounted to the back of, and drives through, the center of the tilt axis table. Both the L and TDL tables feature ±100 degree tilt axis range.

The L series was primarily designed for light duty such as laser applications, EDM or cutter grinding applications since it has no outboard support. However, preliminary testing of both the 6.5- and 10-inch prototypes show excellent rigidity, and Troyke now recommends the L-6.5 and L-10 for standard machining applications requiring 4th and 5th axis.

Other new products introduced by Troyke at IMTS 2000 include: the H-10, 10-inch diameter, high speed, harmonic drive table equipped with a Mectrol harmonic drive for high speed (0-80 rpm) contour machining and indexing,n the T-5C, servo collet fixture, single or multiple spindle, equipped with a pneumatic draw tube for use with 5C collets, step collets or manual chucks andn the DL-16.5, vertical, 16.5-foot diameter table equipped with a 6.1-inch cent hole and pneumatic braking.