Chassis system drives 24-station medical assembly

Edited by Mike Santora

The TR1100 ring style chassis features a ring indexer, stationary plates, and riser. These are all housed in an octagon-shaped frame design enclosed with a guarding system on the lower half for protective access to controls and mounting automation.The system was manufactured, tooled, mounted, and machined complete by WEISS at its Willoughby, OH facility.

A west-coast medical parts manufacturer was recently faced with the challenge of creating a closed female luer valve with a robust system featuring 24 install stations for a 3-5 piece assembly production process. This manufacturer’s medical product line provides patients and caregivers with devices that help improve patient outcomes by minimizing bacterial ingress that can cause bloodstream infections, and preventing exposure to infectious diseases or hazardous drugs. To create the valve the company sought the help of WEISS and its subsidiary WEISS North America, Inc. For the project WEISS completed three, turnkey TR1100, ring-style chassis systems.

The TR1100 ring style chassis features a ring indexer, stationary plates, and riser. These were all housed in an octagon-shaped frame design, that was enclosed with a guarding system on the lower half for protective access to controls and mounting automation.

The system was manufactured, tooled, mounted, and machined complete by WEISS at its Willoughby, OH facility. Here’s how they did it.

TR1100 / MEDICAL MULTI-TASK CHALLENGE:

WEISS engineers had to build a base machine chassis that could accommodate 24 install stations for a 3-to-5 piece multiple size medical valve assembly process that included: loading, pressing, ultrasonic welding, leak testing, inspection and ejecting.

At the heart of the system, the TR1100 Series rotary indexing rings have a large central opening (up to 1750 mm), flat design, and high-level parts accuracy. The ring-shaped design allows extra free design space, and the rotating aluminum ring can be adjusted to specifications in terms of diameter and thickness.

The TR1100 modified chassis design was based on the client‘s request for the octagon shaped frame beneath the top plate. This fully enclosed guarding undercarriage system is made from a combination of aluminum extrusion and sheet metal fabrications that included six bolt-on panels and two swinging door panels for access to controls. The entire frame was powder coated.

The frame extrusion also needed to be flush with both the top plate and the mount enclosure doors. The index table has a 2-in. thick aluminum riser, the octagon table top is 63-in. across flats and 1.25-in. thick. The 48-in. diameter aluminium dial plate is 1.00-in. thick and the 44-in. diameter stationary tool plate is 1.25-in. thick. All chassis system plates featured a hard coat anodized finish that is essential in providing superior durability.

TR1100 rotary indexing rings specs:

Dial ring outside diameter: min. 1100 mm
Dial ring inside diameter: max. 800 mm
Ring thickness: min. 25 mm
Overall height of assembly (from base to top of ring): 70 mm
+ ring thickness
Indexing precision (degree seconds): ± 18″
Indexing precision in radian measurement: ± 0.048 mm
(at ø 1100 mm)

HP70 / SPEED & ACCURACY ACCESSORY:

For mounting automation inside the guarding frame, it was also requested that WEISS engineers mount some of their HP70 Pick-and-Place direct-drive components. The HP70s delivered 70 mm of vertical stroke with 225 mm of horizontal stroke. The HP70 tops out at over 100 cycles per minute with repeat accuracy of 0.01mm.

Key to the HP70’s design, is a drive concept that works with two linear motor axes that feature a ‘knuckle‘ design on the y/z axis−eliminating the need for another linear motor for the z axis.

Ultimately, the WEISS engineering group provided a one-source medical parts assembly solution−delivering a 1.25 second index cycle time with an indexing table speed of .33 seconds−from station to station.

WEISS
www.weissna.com