DC VOLTAGE DETECTOR

• US 20170082664A1
• Filed: 05/14/2015
• Published: 03/23/2017
• Est. Priority Date: 06/04/2014
• Status: Abandoned Application

• Current Assignee: Hasegawa Electric Co., Ltd.
• Original Assignee: Hasegawa Electric Co., Ltd.
• Inventors: Yamada, Hiroshi
• Application Number:
  US15/310,922
• Publication Number:
  US 20170082664A1
• Time in Patent Office: Days
• CPC Class Codes: G01R 15/16 using capacitive devices
• CPC Class Codes: G01R 19/00 Arrangements for measuring currents or voltages or for indicating presence or sign thereof G01R5/00 takes precedence; for measuring bioelectric currents or voltages A61B5/24
• CPC Class Codes: G01R 19/155 Indicating the presence of voltage

Abstract

A DC voltage detector, which is configured to detect the presence or absence of a DC voltage in a detection target (21) through bringing a detection electrode (11) provided inside a housing (23) to a vicinity of the detection target (21), includes an AC generation unit (12) configured to generate an AC current corresponding to the DC voltage through changing a capacitance, the AC generation unit (12) being arranged between an inter-electrode stray capacitance (C₁) formed between the detection target (21) and the detection electrode (11) and a ground stray capacitance (C₂) formed between an internal shield (30) of the housing (23) and a ground.

Claims

1. A DC voltage detector, which is configured to detect the presence or absence of a DC voltage in a detection target through bringing a detection electrode provided inside a housing to a vicinity of the detection target,

the DC voltage detector comprising an AC generation unit configured to generate an AC current corresponding to the DC voltage through changing a capacitance, the AC generation unit being arranged between an inter-electrode stray capacitance formed between the detection target and the detection electrode and a ground stray capacitance formed between an internal shield of the housing and a ground.

2. The DC voltage detector according to claim 1, wherein the AC generation unit comprises:

a variable capacitor connected to an output side of the detection electrode; and

a piezoelectric element configured to change a capacitance of the variable capacitor.

3. The DC voltage detector according to claim 1, wherein the internal shield is formed on a portion inside the housing excluding the detection electrode.

4. The DC voltage detector according to claim 1, wherein the detection target comprises a grounding circuit.

5. The DC voltage detector according to claim 1, wherein the detection target comprises a non-grounding circuit.