Molded Parts: Stamp, Place, Remove, Inspect

Filtertek, Inc. is a world innovator in filter technology. The Hebron, IL, manufacturer makes custom filtration products and fluid control devices for automotive, healthcare and consumer product applications. The company’s ingenuity is reflected in a portfolio of more than 340 issued patents and pending patent applications for novel designs of fuel filters, transmission sump filters, semi...

09/01/2008


Filtertek, Inc. is a world innovator in filter technology. The Hebron, IL, manufacturer makes custom filtration products and fluid control devices for automotive, healthcare and consumer product applications. The company’s ingenuity is reflected in a portfolio of more than 340 issued patents and pending patent applications for novel designs of fuel filters, transmission sump filters, semi-solid product dispensers, check valves, IV filters, and more. But it had a problem. Said John Leahey, Filtertek’s director of domestic medical products, “We needed to increase the output of injected molded parts to meet our customers’ demand.”

HiTech Manufacturing Solutions, Inc. in Green Bay, WI, specializes in designing and building custom automation machinery. Project Manager Larry DeGroot worked on a concept for Filtertek and HiTech was consequently contracted to build and integrate automation machinery with a molding machine. As a result of HiTech’s integrated approach, Filtertek doubled its production volume while significantly lowering and/or eliminating labor and material usage.

What Filtertek had before

“The biggest challenge in designing this machine,” DeGroot said, “was thought to be the punching and handling of the membrane. As it turned out, this was easier than expected.”

However, unexpected challenges occurred in the speed and handling of parts during the unload and inspection stages, said DeGroot. “But with our strong engineering skill set and communication with the customer, we were able to come up with robust solutions,” he said.

Previously, for example, the screen inserts in one of Filtertek’s products were produced in a manual, sheet-fed operation. In the new, automated machine, the screen insert is made from a ribbon feed and the inserts are loaded directly into the part cavities. Also, the parts used to be inspected as a separate process. In the new line, DeGroot says, 100% inspection is done in-line, at twice the production rate.

HiTech designed, built and integrated the automated machinery to:

  • Remove runners;

  • Punch and place a hydrophilic membrane;

  • Remove finished filters;

  • Vision inspect 100% of filters for the presence and placement of the membrane; and

  • Test air flow rate in process on a statistically significant sampling of finished filters.

The system is designed to produce 48 parts every 15 seconds. Parts are sorted and retained by mold base (four mold bases) from the molding machine. A Rockwell Automation Allen-Bradley MicroLogix 1500 PLC is used with DeviceNet I/O. A Pro-face Xycom touchscreen industrial PC running Windows XP is the HMI hardware. Rockwell RSView Machine Edition software is used for the operator interface, employing embedded ActiveX controls to connect two Cognex DVT machine vision cameras. Through the interface, the operator can view batch controls, machine status, machine position, alarming, the vision system interface with real-time images, and production data/statistics.

After the first molding station completes a set of parts, the runners are ejected and captured for recycling. Sensors and fault logic ensure runners are not left in the mold.

Next, a punch press cycles on demand and cuts 48 pieces of membrane as the molding press table indexes. A vacuum fixture picks up these membrane discs, retracts, and lowers them into molded component halves. MAC pneumatic controls ensure that all filters are inserted into the parts.

At the filter ribbon handling stage, six 3-in. reel hubs are mounted on the punch press stand. A servo drive advances the filter ribbons to minimize waste in the ribbon and ensure that no splices are punched. Reel sensors alert operators when the reel is getting low on material.

Handling finished parts

To remove the molded parts, a servo-driven carriage is used to move grippers over finished parts. Finished parts are positioned by the mold where they can be gripped and taken from the mold/molding machine by an end-of-arm removal system. While transferring from the mold, runners are automatically removed from the end-of-arm grippers. The carriage has a servo-driven slide to allow the parts to be unloaded into zones on an inspection conveyor. Loading into zones optimizes unloading speed.

A servo-driven conveyor with fixtures is used to sequence parts for inspection and testing. Parts are tracked along the conveyor using a known, repeatable unloading sequence and data shifting to follow the conveyor. This allows the parts to be sorted into appropriate individual bins matching mold bases. Parts are sampled off the inspection conveyor by the flow testing equipment. The sampling cycle rate is user selectable, up to three times per hour. Sampling allows each mold cavity to be tested during a test cycle.

Each part that is not flow tested is inspected by a Cognex Model DVT 515 vision system. “The vision system uses telecentric lenses and on-axis lighting to allow internal and external inspection of filters,” says DeGroot. “This is needed because the filter is half way down the inside of a cylindrical part. A telecentric lens allows simultaneous inspection of the inside and outside of the filter.”

Filter media is tested for presence and correct placement. Good parts are removed using pneumatically operated suction and guided into a servo-driven parts diverter. Bins for each mold allow the diverter to segregate good parts, which allows the user to monitor product quality for each mold separately.

This new concept in molding automation provided the customer with a reliable machine that produces a quality product, including 100% visual and in-process air flow rate sampling inspection. As a result of HiTech’s integrated approach, Filtertek greatly increased its production while significantly lowering and/or eliminating labor and material usage.



Author Information

Renee Robbins is senior editor of Control Engineering. She can be reached at renee.robbins@reedbusiness.com




No comments
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2013 Top Plant.
The Product of the Year program recognizes products newly released in the manufacturing industries.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
The true cost of lubrication: Three keys to consider when evaluating oils; Plant Engineering Lubrication Guide; 11 ways to protect bearing assets; Is lubrication part of your KPIs?
Contract maintenance: 5 ways to keep things humming while keeping an eye on costs; Pneumatic systems; Energy monitoring; The sixth 'S' is safety
Transport your data: Supply chain information critical to operational excellence; High-voltage faults; Portable cooling; Safety automation isn't automatic
Case Study Database

Case Study Database

Get more exposure for your case study by uploading it to the Plant Engineering case study database, where end-users can identify relevant solutions and explore what the experts are doing to effectively implement a variety of technology and productivity related projects.

These case studies provide examples of how knowledgeable solution providers have used technology, processes and people to create effective and successful implementations in real-world situations. Case studies can be completed by filling out a simple online form where you can outline the project title, abstract, and full story in 1500 words or less; upload photos, videos and a logo.

Click here to visit the Case Study Database and upload your case study.

Maintaining low data center PUE; Using eco mode in UPS systems; Commissioning electrical and power systems; Exploring dc power distribution alternatives
Synchronizing industrial Ethernet networks; Selecting protocol conversion gateways; Integrating HMIs with PLCs and PACs
Why manufacturers need to see energy in a different light: Current approaches to energy management yield quick savings, but leave plant managers searching for ways of improving on those early gains.

Annual Salary Survey

Participate in the 2013 Salary Survey

In a year when manufacturing continued to lead the economic rebound, it makes sense that plant manager bonuses rebounded. Plant Engineering’s annual Salary Survey shows both wages and bonuses rose in 2012 after a retreat the year before.

Average salary across all job titles for plant floor management rose 3.5% to $95,446, and bonus compensation jumped to $15,162, a 4.2% increase from the 2010 level and double the 2011 total, which showed a sharp drop in bonus.

2012 Salary Survey Analysis

2012 Salary Survey Results

Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Society for Maintenance and Reliability Professionals an organization devoted...
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.