Cutting Capability of Microdrills in Nonstep Drilling

There is a high demand for microdrilling processes to drill microholes with diameters equal to or less than 0.2 mm for use in fuel injection nozzles. In this study, nonstep drilling methods are developed for high-efficiency processing. Herein, the effects of the cutting oil supply method and the drill’s feed rate on the developed thrust force and torque during drilling are investigated. Accordingly, it is shown that drop supply of the cutting oil is the optimal method for nonstep drilling because the oil is sucked into the microhole. Furthermore, a high-feed rate is preferred because it produces continuous chips.**This paper is a translation with revision of the paper: M. Uchiyama and N. Sakata, “Cutting capability of micro drills in non-step drilling 1st report: Optimization of cutting oil supply and drill feed,” J. of the Japan Society for Abrasive Technology, Vol.59, Issue 1, pp. 27-31, doi: 10.11420/jsat.59.27, 2015 (in Japanese).

Texture and Antioxidant Properties of Puffed Pounded-Unripe Rice Coated by Marigold Extract as Affected by Fluidized-Bed Coating Conditions

We investigated the effects of fluidized-bed coating parameters on texture and antioxidant properties of puffed pounded-unripe rice (PPUR) coated by marigold extract with variations of inlet air temperature of 50, 60 and 70°C and coating solution feed rate of 5, 7.5 and 10 ml/min. The results showed that increasing inlet air temperature tended to reduce the hardness of coated PPUR, while the adverse effect was found with increasing feed rate. Both parameters did not significantly affect the crispiness. We also found that fluidizing air temperature and feed rate significantly affect total phenolic content (TPC), total flavonoid content (TFC) and their antioxidant activities. Higher feed rate slightly increased TPC and antioxidant activities as determined by DPPH and FRAP assays, but not for TFC. As mostly found in medicinal plants, all antioxidant properties decreased when temperature increased. Based on the amount of TPC and TFC and their antioxidant activities, we recommend low inlet air temperature and high feed rate to improve health benefits of puffed pounded-unripe rice as a breakfast cereal. However, agglomeration must be concerned when using high feed rate.

Non-Contact Measuring Modeling and Simulation of CNC Machine Tools under High Feed Rate Condition

This article sets forth a new precision measurement method of CNC machine tools. The method incorporates the laser interferometer and the measurement principle of the double ball bar (DBB), and can measure the machine tool precision under the high feed rate condition. The generalized measurement model of three-axis has been built. Data analysis software is developed to simulate the run condition of machine tools. The repeatable experiment results proves that the method is feasible and its precision is higher than DBB`s.