Auto Band Positioner

PMC Markerband Positioner and Precrimper

Simple, accurate, and fast positioning and precrimping of marker bands
  • Secure Precrimping with Hexagonal Crimp
  • Accurate Placement
  • Simple Control
  • Reliable Mechanical Positioning

The Blockwise marker band positioner / precrimper model PMC is a tabletop machine that slides bands along a catheter inner member or other substrate to position them, then lightly precrimps the bands into a hexagonal shape to hold them in position prior to swaging.

The band positioner / precrimper model PMC uses a simple, reliable, mechanical approach to positioning bands, with no optical sensors or vision systems. The PLC control software can be set up by a novice in just a few minutes.

In a typical application, the product consists of an “inner member” (plastic tube) slipped over a mandrel, with two bands placed on the mandrel.

In a typical operating sequence (after setting up a recipe in the PLC) the operator places the catheter inner member with bands into the side-loading gripper, the mandrel into the crimper, and then presses the START button. The crimper closes, and the operator touches the tip of the inner member against the face of the crimper dies (providing a position reference for the machine), then presses the START button again. The machine then uses the crimper, with almost zero closing force, to gently slide the bands, as a group, along the inner member to a known position. Then, one-by-one, the crimper is used to grab the outside of each band to move it away from the group, then push the band into position using the face of the crimper dies, then precrimp the band into a hexagonal shape.

Cycle time depends on the process settings; typical cycle time for PTCA-type catheters is about 28 seconds.

The 6-jaw crimper has 3 crimp-force settings that are used and commanded by the PLC: 1) a high crimp force (diameter-limited) for precrimping the bands into a hexagonal shape, 2) a low crimp force for grabbing the outside of a band that’s adjacent to another band without deforming the band, 3) a very low (almost zero) force used when sliding the bands along the catheter by pushing them with the face of the dies. The inner member is not harmed by the dies when sliding the bands.

When precrimping the bands, the crimper diameter can be limited by a mechanical stop set by a fine-pitch adjusting screw.

The PLC software provides up to 100 user-changeable “recipes” that contain:
  1) The number of bands to be positioned and precrimped (1 to 25).
  2) The length of the bands.
  3) The desired positions of each band from the tip of the inner member to the right side of the band

The model PMC band positioner / precrimper provides very accurate results. The standard deviation of band-to-band position is normally about 0.025 mm. The subsequent swaging step will slightly elongate the bands and the plastic tube beneath the bands, so the band-to-band and tip-to-band distance changes measurably. Those changes can be measured and compensated for when setting up a recipe for the model PMC machine, so that the average post-swage positions match the desired values. Besides shifting the average positions, the swaging process also adds its own position variability; in fact the additional variability from the swaging process is usually more significant than that from the model PMC positioning process.

Required Installation Connections – Model PMC

Description Physical Specs Functional Specs
Electric Power Powers the control system, HMI, heaters, etc. C13 Coupler (IEC 60320) 100-240 VAC 2A 50-60Hz
Compressed Air Powers the Simpluer connector, etc. (see Knowledge Base: Compressed Air & High Pressure Gas Connections) Instant Tube Fitting Accepts ¼-inch OD Plastic Tube 6.9 to 8.3 bar (100 to 120 psi)

Model PMC Markerband Positioner and Precrimper

Simple, easy-to-use, automatic machine for placing markerbands on catheters. Uses reliable mechanical method that can be set up in just minutes. Great choice for production environments.

Typical Cycle Time 2 bands: 28 seconds
Standard Deviation Band-to-Band Distance: 0.028 mm
Allowable number of Bands: 1 to 25
Band Diameter Range: 0.25 to 4.7 mm
Maximum Tip-to-Band Distance: 290 mm
Side-Loading Gripper Die Material: Acetal Copolymer Plastic
6-Jaw Crimper Die Material: Hardened Stainless Steel