I have summarized some of the main items that should be taken into consideration when buying a profile projector. Please feel free to contact us (www.sinowon.com ) with any questions regarding sales applications, or competitive products.
Step one. Is a horizontal or vertical light path model best for your application?
Vertical light path instrument have a beam of light traveling vertically. Parts being inspected are placed on a plate of glass that the light beam travels through.
Vertical profile projectors are ideal for flat parts like gaskets, O rings, stamped parts and electronics.
Vertical profile projector of SINOWON feature quick release mechanisms on both axes making measurements on our vertical machines much faster than on horizontal machines which feature quick release on only 1 axis.
Horizontal light path instruments have a beam of light traveling horizontally across a work-stage. This type of machine is ideal for large heavy parts and shafts to be held on V blocks or between centers. Typical applications include castings, transmission shafts, thread form measurement and machined components.
Step 2, what screen size and stage size best suits your applications?
SINOWON profile projector screen sizes from 300mm to 600mm are available. Before choosing a screen size, determine how much of the part really must be viewed at one time.
When using a digital readout system it is not necessary to view the entire part to measure it. Calculations can be made by dividing the screen diameter by the lens magnification.
For example using 10X lens on a 300mm profile projector would enable viewing 30mm of the part on the screen 300/10=30.
Verify that the work-stage size, travel and weight capacity will accommodate all of the parts that are intended to be inspected. In general, screen sizes 300mm and smaller are bench-top units with weight capacities up to 50kg.
Step 3, what lens/lenses you will require?
Follow the chart below to decide what lens will match the tolerances required. A basic rule of thumb is that a typical attentive operator can repeatedly discriminate. 004” on the comparator screen. Dividing the “discernible resolution” by the lens magnification determines the minimum resolution attainable for each lens.
|
Lens magnification
|
Discernable resolution
|
|
5X
|
0.0008” 0.020mm
|
|
10X
|
0.0004” 0.010mm
|
|
20X
|
0.0002” 0.005mm
|
|
50X
|
0.00008” 0.002mm
|
|
100X
|
0.00004” 0.001mm
|
Step 4, Do I need a digital readout?
Select a basic XY digital readout if only positions and distance are required. If measurement of circles, angles, and parametric distance is required, then select a DRO with geometric capability. Automatic edge sensing should be considered to eliminate operator subjectivity and increase repeatability and accuracy. SINOWON provide two models of DRO, DP100 and DP300. For details www.sinowon.com
Step 5, what options or tooling will be required?
Repeatability and accuracy will suffer if the work-piece is not properly and securely held. Careful consideration should be given to tooling and to the surface on which you place your profile projector.
