发明名称 |
Zero-crossing detector circuit and image forming apparatus having the same |
摘要 |
A zero-crossing detector circuit includes: a first capacitor including a first electrode configured to connect to one end of an AC power supply and a second electrode; a second capacitor including a first electrode configured to connect to the other end of the AC power supply and a second electrode; a current path, which is connected in series between the second electrode of the first capacitor and the second electrode of the second capacitor, and which is connected to a reference potential, and which generates a second-electrode-side voltage when the AC current passes through the current path; a signal converting circuit, which is connected to the AC power supply to receive the second-electrode-side voltage and then converts the second-electrode-side voltage into a pulse signal; and a detecting unit, which detects a pulse period of the pulse signal, which and detects zero-crossing points by using the pulse period. |
申请公布号 |
US8912468(B2) |
申请公布日期 |
2014.12.16 |
申请号 |
US201213560201 |
申请日期 |
2012.07.27 |
申请人 |
Brother Kogyo Kabushiki Kaisha |
发明人 |
Inukai Katsumi |
分类号 |
H05B1/02;G01R19/175;H02M1/08;H02M7/219 |
主分类号 |
H05B1/02 |
代理机构 |
Merchant & Gould PC |
代理人 |
Merchant & Gould PC |
主权项 |
1. A zero-crossing detector circuit comprising:
a first capacitor including a first electrode configured to connect to one end of an AC power supply and a second electrode; a second capacitor including a first electrode configured to connect to the other end of the AC power supply and a second electrode; a current path, which is connected in series between the second electrode of the first capacitor and the second electrode of the second capacitor, and which is connected to a reference potential, and wherein the current path causes an AC current output from the AC power supply to pass through the current path when the AC current returns to the AC power supply, and generates a second-electrode-side voltage when the AC current passes through the current path; a signal converting circuit, which is connected to the AC power supply to receive the second-electrode-side voltage and then converts the second-electrode-side voltage into a pulse signal; and a detecting unit, which detects the presence of a pulse period of the pulse signal and detects zero-crossing points of an AC voltage of the AC power supply by using the pulse signal. |
地址 |
Nagoya-Shi, Aichi-Ken JP |