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Complete Robotic Dispensing and High Precision Systems
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Hollow Horizontal Gasket Dispensing Hollow Horizontal Gasket Dispensing
News 2015-05-04

    Please note: our hollow gasket dispensing technology is patent pending.

Foam in place gasketing is a versatile process, but requires very expensive equipment. Just the foaming equipment is typically $50,000 and when all of the various required components are in place the pumping equipment can spiral to $100,000 pretty easily. While there are PU foam systems that are less expensive, so far we have found them to be maintenance intensive. Ideally, we would like to have the features of foamed gaskets without the upfront, steep hardware costs or maintenance headaches.
Hollow gaskets can fulfill many of the roles assigned to foamed gaskets. These gaskets can be produced using simple materials such as silicones and the pumping equipment is almost an order of magnitude less costly.
Because these are extruded gaskets, many unique profiles can be applied and we are no longer constrained to simple circular sections with the typical height:width ratios of 1:2 or at best 1:1. Instead, we have produced ratios not only of 1:1 but also up to 1.5:1. The profiles can be other than the classical circular section such as triangular, rectangular, "M' shaped, or whatever best serves the sealing need.
These gaskets will have one or more hollow segments and the segments can be filled with air, nitrogen, or even conductive polymers.
These gaskets can even form sealed channels that can transport air or other fluids in a specific pattern, thus forming heat exchangers or allowing seals that can be pressurized AFTER the mating surfaces have been engaged.
Hollow gaskets have several advantages over traditional foamed gaskets:
1) Tall profiles can readily be formed. Current testing has produced 0.5" tall (12.5mm tall) seals.
2) Because of the extrusion process, the height of the gasket can be held to a very high tolerance.
3) Can be easily compressed more than 60% of overall height with light compressive force
4) When compared to the traditional 1:2 (H:W) profile of a foamed seal with 50% foaming, hollow seals use 47.5% less material.
5) When compared to the traditional 1:2 (H:W) profile of a solid material seal, hollow seals can use 74% less material.

In one particular sample case the overall seal height was 0.48" (12.98mm) and the weight of material per inch was 1.56g.

One issue to keep in mind is that these seals are extruded horizontally onto a surface. As a result, ideal applications are not endless! We can only approximate endless by running the start and stop parallel to one another as seen in the 13mm tall sample photo below. On the other hand, this method allows precise gasket extrusion with many possible profiles.

    Images

  1. 13mm tall seal
  2. 10mm tall seal showing cross section

Hollow Vertical Gasket Dispensing Hollow Vertical Gasket Dispensing
News 2015-05-04

    Please note: our hollow gasket dispensing technology is patent pending.

This variation of hollow gasket dispensing offers a direct replacement for traditional solid gasket dispensing.
Hollow gaskets in this category offer:
1) Greatly reduced material usage
2) The effective force of compression is far less than it would be for an equivalent solid gasket.
3) For many RTVs and UV cure silicones, the cure time is reduced and intensity requirements are also reduced.

Small and large gaskets were done in Novagard 400-150, an oxime moisture cure RTV.

    Images

  1. Large gasket (0.34 inch) with hollow
  2. Medium hollow gasket with pencil (0.29 inch)
  3. Small hollow gasket with pencil (0.16 inch)
  4. Micro hollow gasket (0.06 inch) cutout
  5. Micro hollow gasket with penny
    Links

  1. Novagard 400-150 TDS link
  2. General Novagard Solutions website

Head Mounted Theta-Z axis applications
News 2015-02-21

    Originally developed back in 2007, our theta axis calibration system is rather unique. The difficulty with head mounted dispense tips that rotate is that the tip really needs to be compensated during all degrees of rotation. A fixed dispense tip is relatively easy to calibrate - check X, Y, and Z offsets and tip diameter and you can readily generate a real world offset to the dispense tip. If the tip rotates, these offsets no longer apply.
In order to calibrate a tip with a bend you also need to consider the distance from the center of rotation to the orifice (what we call the arm). During rotation a circle is circumscribed by the arm and from that you can derive the center of rotation. Effectively the tip has its own coordinate frame that gets applied to the pattern during run-time.
In the past, a tip with a bend might have been manually rotated into position once the head theta was in the home position. That is no longer necessary and because of our camera-based tip calibration for theta, the results are astoundingly consistent.
Equipped with information on the arm and a calibrated center of rotation, it is now possible to do some things that are quite interesting. For example, as long as the tip does not physically interfere with the part (the bend accomplishes this typically) it becomes possible to dispense on an inside radius that is smaller than the arm length!
Perhaps that last does not sound remarkable, but as with all of our applications, we attempt to use CAD data rather than modifying the dispense path to accommodate the configuration of the dispense equipment.

    Images

  1. Calibration of form-bent tips

20" Cartesian Positioning Base 20" Cartesian Positioning Base
News 2014-04-20

    We are now announcing our larger base platform! While our standard CP16 platform has a depth of 31 inches, allowing a safe Y travel of 15 1/2 inches and a max work area in Y of 15 1/2 inches, our new platform is 39 1/2", giving a safe Y travel and work envelope in Y of 19.6" or 498mm. If the application has stations on Y, an option that limits maximum pallet size, Y axis travel can be configured for 28.5" or 723mm.
This platform uses our standard X configurations. As a result, X standard travels of 16" and 24" are available off the shelf. We can readily supply X travels of up to 32" on our CP platforms.
Extended Y axis travel is most helpful in those applications that benefit from on-board UV cure systems. These on-board systems are efficient, cost effective, and safe as the operator never handles uncured product. Depending on application cure demands, both Uvexs and Dymax supply UV cure systems that integrate well with CP platforms.

    Images

  1. CP Sytems expand!

Machine footprint and safety Machine footprint and safety
News 2013-07-15

    Safety on the manufacturing floor is always a critical consideration but for some reason, it is not an uncommon practice to market split axis machines with work envelopes larger than the footprint of the machine. This means that the moving pallet which is typically on the Y axis moves past the front (and rear) edge of the machine. Operators are then potentially in the path of the pallet as it moves back and forth.
In any reasonable machine design, no motion component should project beyond the footprint of the machine. A machine with a 500mm travel in the Y axis should have a base 1000mm from front to back at least. Of course the pallet can be design limited to not extend beyond the footprint, but this then shrinks the dispensable area in the Y and so purchasing a machine that doesn't have twice the footprint as the travel in the Y is not an effective use of funds!
In short, for any split axis design such as our CP16, CP2416, and our newly designed CP2420, the Y axis travel should be no more than half of the Y machine base footprint.

    Images

  1. CP16

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©2008, 2009, 2010, 2011 New Precision Technology, Inc.
P.O. Box 81956
Pittsburgh, PA. 15217
1-412-596-5948