Checking Fixtures by Unique Circle Engineering Private Limited
Checking fixtures is an important part of our activity, we design and manufacture serial and prototype checking fixtures forinterior plastic parts of vehicle, like dashboards, consoles, door panels,but also used for exterior plastic parts vehicle typebumpers, trims, strip holders, calender… We design and manufacture some assembly fixtures of metal parts or gluing fixtures ofcomposite-made-parts.
It also manufactures fixtures for all types of Head & Tail Lamps, Holding Fixtures, Assembly Fixtures, Cooling Fixtures, Vibration Welding Fixtures, FRP Components, Special Purpose Machinery (SPM) for Plastic Components, Ultrasonic Welding Fixtures, Robotics Fixture and Punching Tools for plastic components and is catering to a wide scope of industries in the diverse range of the automotive market sector. Established for over 15 years, Unique Circle has the technical competence and capabilities to manage large Scale complex projects and regularly manage customers' complete tooling requirement from Concept Design, CAD/CAM Modelling to Development and Production and after sales support.
Unique Circle has a fully staffed and experienced fixture design team. Our designers have worked in various sectors of this industry giving us a wide range of design capabilities. We are currently designing on Catia V.5 and also Unigraphics which are maintained at the latest revision levels in use. We are well versed in all types of fixtures and gages as well as secondary tooling. Our facilities are fully integrated to provide instantaneous information from top to bottom.
We do check fixtures for stamped metal parts, complete frame assemblies, bumpers, headlights/taillights etc. You name it, if a part needs to be checked we can build you a gauge for it. Our manufacturing process begins with the customer approved design. Meeting with designers, the tooling shop manager and CNC programming manager discuss details and schedules. Once the issue of how best to fabricate each of the components is decided, the project is scheduled to be completed as the customer requires. The final assembly is CMM checked and certified to meet or exceed desired specifications and tolerances.
Unique Circle has been manufacturing checking fixtures for the past 25 years mainly for the Automotive & Aerospace industries, all fixtures are designed using the latest in 3-D CAD software allowing us to present fully working CAD models including the working environment and ergonomics prior to manufacture.
Fixtures range in complexity from simple CMM holding jigs up-to full production checking systems including electronic part sensing & automatic data recording, with sizes ranging up-to full car body (Internal & external) checking fixtures we can offer a complete service to suit our customers requirements.
All fixtures come complete with a CMM report, Gauge R & R study and a Work Instruction manual, if required we also offer on-site installation & training.
In order to carry out periodical verifications on your checking fixtures, it is
important to have references enabling you to position the fixture in a coordinates
system. This alignment can be geometric or by 3 centres
The alignment can be done by:
Machined planes on the base plate
Part aligning elements (RPS)
Sights or spheres driven into the base plate
Rectified steel bushings driven into the base plate
The geometric alignment system is more precise, and is probably the best one on a
metrological point of view; yet, it is also the most complex and expensive system,
since it aligns the checking fixture by using the same areas as the ones used to align the part to be measured.
The most commonly used system is the one using three rectified bushings, as it
enables to get a precision very close to theory with more reasonable costs.
The part RPS, indicated in the 2D drawing, are usually used to align the part.
Remember to identify clearly the location of the RPS, and how you want to
simulate them. The fixations are usually an accurate reproduction of the real
environment of the part, but it is also possible to represent only the theoretical
The cost of each system can be quite different, and so are the measurement results
each system can provide; consequently, it is very important to define them from the beginning. The part alignment system must prevent the part from being mounted in different positions on the checking fixture; this can be done by using conic and retractablecentring elements, that can absorb the tolerances of the elements used to centre the part. This is the only way to ensure the checking fixture repeatability for measurements, and good results in the R&R studies.
In many cases, the checking fixture will be used to carry out as much checks in the
production chain as in the metrology laboratory. If the checking fixtures are to be
used to do measurements with a CMM machine, you have to say so, in order to
design the alignment systems in a way allowing the access of the CMM machine probe.