D.L. Klipp Engineering

Project Examples

Tray Denester/Dispenser

A major manufacturer of molded paper fruit trays had an urgent requirement for an apple tray dispenser to be used on automated “commit to pack”  packing lines.

The specifications were quite stringent. The machine had to dispense all tray sizes manufactured by the three major tray providers without any adjustment. The dispenser footprint had to be very compact to fit into existing packing lines.  Near 100% reliability was demanded as well as easy loading and operation.  The dispensing rate was to be up to 40 trays per minute.  No vacuum was to be used to handle the trays.

The resulting dispenser design is now the most accepted and reliable machine in the industry.  Over two hundred of the devices are in service today.  The machine is pneumatically operated and uses serrated blade segments to pick the trays and pull them from the bottom of a pair of top loaded stacks.  The unique approach to locating the trays for picking lead to the award of U.S. Patent #6,099,239.

Spring Forming Machine

A mattress manufacturer used a special cam driven machine to produce a bedspring of a rather unique design.  The cams had numerous adjustable segments so that the proper spring geometry could be attained.  The kinematics of the cams were horrendous and the process productivity was extremely limited.  To increase production and repeatability of spring shape, servo drives were applied to the machine with limited success.  The desired production rate was 70 springs per minute and they could only attain 37 spm because of poor motion dynamics.

We designed a motion generation system for the four axis arrangement to allow for adjustment of the motions while producing acceptable motion kinematic characteristics.  The fact that the motions were constrained by the necessary spring geometry proved to be quite a challenge.  The machine was tested at speeds up to 76 springs per minute, limited only by the wire unwinder on the prototype.  Motion dynamics were a paradigm shift from the previous arrangement.

Paper Plate Machine

A major manufacturer of molded paper plates was at the mechanical speed limit of their molding machine.  Any attempt to increase throughput degraded product quality and caused unacceptable vibration.

A study was undertaken to review the opportunities to optimize the motion timing and acceleration forms of the limiting machine actions.  By increasing the time taken to index a massive drum element of the machine and incorporating an acceleration form best suited for high inertia loading, it was stated that a mechanical speed increase of 25% could safely be expected.  A second supporting cam motion was also redesigned for optimum performance.

The prototype results were so successful that a plant-wide program was undertaken to upgrade 11 of 13 existing machines.  Based on an expected productivity increase of  20% (other process factors being considered), the internal rate of return  for the project was calculated to be 110%.

The cam upgrade and a subsequent drive system redesign has this plant running today at a productivity rate 80% above the base rate prior to the conversion program.  The reduced manufacturing costs and increased production have resulted in great bottom line profits, facilitated price containment and supported new market penetration.

In addition, previous problems with cam track wear and life issues were examined.  A cam material change was made as part of the upgrade project that resulted in an increase in cam service life by 15 to 20 times.  A cam follower servicing feature was also included that reduced the time required to replace followers from 5 hours to just 1 hour.