Keiji Nakanishi

Title: Innovations by Keiji Nakanishi in Noise Control Technology

Introduction

Keiji Nakanishi is a notable inventor based in Takatsuki, Japan. He has made significant contributions to the field of noise control technology, particularly in refrigeration systems. With a total of 6 patents to his name, Nakanishi's work focuses on reducing noise generated by rotary compressors in refrigerators.

Latest Patents

Nakanishi's latest patents include a low noise refrigerator and a noise control method. In his low noise refrigerator design, a rotary compressor, which is a primary noise source, is strategically placed within a machine chamber. This chamber features a one-dimensional duct construction that minimizes noise by having a cross-sectional dimension smaller than the wavelength of the noise to be reduced. A vibration pick-up is located near the rotary compressor to detect vibrations that correlate with compressor noise. The output signal from this pick-up is processed by a control circuit, which drives a sound generator to produce a control sound that cancels out the compressor noise.

Another significant patent involves a refrigerator equipped with a noise attenuating function. This design includes a cabinet with storage and machine compartments, where a compressor is housed. A noise detector within the machine compartment detects noise from the compressor and converts it into an electrical signal. This signal is then transformed into an acoustic signal for active noise control. A cancellation sound producer generates sound waves that are out of phase with the detected noise, effectively reducing it. An adaptive control circuit continuously adjusts operational factors based on monitoring results to ensure optimal noise attenuation.

Career Highlights

Keiji Nakanishi is currently employed at Kabushiki Kaisha Toshiba, where he continues to innovate in the field of refrigeration technology. His work has not only advanced the efficiency of refrigeration systems but has also significantly improved user comfort by minimizing noise pollution.

Collaborations

Nakanishi collaborates with Yasuyuki Sekiguchi, contributing to the development of innovative solutions in noise control technology. Their partnership has led to advancements that enhance the functionality and user experience of refrigeration appliances.

Conclusion

Keiji Nakanishi's contributions to noise control technology in refrigeration systems exemplify the impact of innovative thinking in engineering. His patents reflect a commitment to improving everyday appliances, making them quieter and more efficient.