The DBA template has the following advantages:

A precision ball that can guarantee a sphericity of less than 50 nm can be obtained from the market for manufacturing a sample that is close to the shape of the product, for example, a template for a modulus of 10 mm and a number of 40 gears.

During the prototype manufacturing process, the installation adjustment of the position between the two spheres does not need to be very precise.

The distance between the two balls can be measured very accurately. The National Institute of Metrology (NMI) is able to issue traceability certificates for this spherical model.

When measuring the DBA template on the involute detector, due to the error of the horizontal position, the center of the template is slightly deviated from the center of rotation of the instrument spindle, resulting in the change of the effective size of the DBA template in the fixed coordinate system of the involute detector. . The effect of this change on the measurement is only considered when the center distance of the two balls changes in the horizontal section. The effect of the deviation between the center of the template and the center of rotation of the instrument on the calibration results can be fully compensated mathematically.

Fig. 3 Output example and evaluation deviation curve of the involute detector measuring the spherical template

Curve 2 in Figure 3 shows a typical measured output curve of an involute detector (MCB: measured hump curve). The expansion angle is large enough to assess the accuracy of the profile. The TCB curve is also shown on the same graph. The difference between the MCB curve and the TCB curve is extremely small compared to the amplitude of the hump curve, so that it is impossible to evaluate the accuracy of the involute detector by observing the magnitude of the difference. This is also consistent with the fact that the use of non-involute models faces the limitations of item (2) above.

Most of today's involute detectors are of the CNC type, and the measured output can be easily stored in the form of data sets (angles of formation, shape deviation). The numerical processing of the MCB and TCB curves is not difficult, and the difference between the two can be accurately obtained by the following formula: DCE = MCB-TCB. This difference is called "evaluation deviation curve (DCE)", and curve 3 in Fig. 3 is an example of the DCE curve.

If the involute detector has no errors, the DCE is a horizontal straight line. The amount of deviation from the horizontal line reflects the error value of the calibrated involute detector. The results of the DCE allow us to determine that the accuracy of the calibration results is higher than the micron level (uncertainty is less than 1 μm). This overcomes the traditional limitations of item (2) above.

A major challenge in preparing prototypes is that it is very difficult to make a template that is the same size or close to a small or large modulus gear product. From this point of view, the spherical template has a fundamental advantage over the involute model because we can buy a high-precision ball that can fit almost any size of gear at a reasonable price (the diameter range of the ball specified in ISO3290) It is 0.3 to 104.775 mm).

Previous page next page

Water Purifier Kitchen Faucets

The faucets used in general households are unified, and there is no distinction between drinking water and water. But in some western countries, to provide special water purification pipeline, it is required to have a water purification faucet. There is no difference between the clean faucet and the general faucet, but the raw water is different.

Water Purifier Kitchen Faucets,Kitchen Mixer Faucets For Restaurant,Brass Water Purifier Kitchen Faucets,3-Way Drinking Water Filter Kitchen Faucet

Kaiping Jenor Sanitary Ware Co., Ltd , https://www.jmjenorsanitary.com