Charger

Patent metadata

Field	Value
Publication number	US-9257855-B2
Application number	US-201313969826-A
Country	US
Kind code	B2
Filing date	Aug 19, 2013
Priority date	Aug 21, 2012
Publication date	Feb 9, 2016
Grant date	Feb 9, 2016

Abstract

A charger in one aspect of the present invention includes: a connecting portion, two protection devices, a charging device, a control device, and a voltage detection device. A first protection device is configured such that its power consumption in a charging inhibited state is lower than that in a charging permitted state. A second protection device is configured such that its power consumption in the permitted state is lower than that in the inhibited state. The control device is configured to respectively set, when the battery is not connected to the connecting portion, the first protection device to the inhibited state and the second protection device to the permitted state, and thereafter switch, when the voltage value of the charging path detected by the voltage detection device is equal to or greater than a predetermined specified voltage value, the second protection device to the inhibited state.

First claim

What is claimed is:

1. A charger comprising:
a connecting portion configured to connect a battery;
two protection devices configured to switch between inhibition and permission of charging the battery;
a charging device configured to stop charging the battery in a case where at least one of the two protection devices is in a charging inhibited state, in which charging the battery is inhibited, and to perform charging the battery in a case where both of the two protection devices are in a charging permitted state, in which charging the battery is permitted;
a control device configured to, when the battery is connected to the connecting portion, bring the two protection devices into the charging permitted state to thereby permit charging the battery by the charging device; and
a voltage detection device configured to detect a voltage value of a charging path from the charging device to the connecting portion,
wherein a first protection device, which is one of the two protection devices, is configured such that its power consumption in the charging inhibited state is lower than its power consumption in the charging permitted state,
a second protection device, which is the other of the two protection devices, is configured such that its power consumption in the charging permitted state is lower than its power consumption in the charging inhibited state, and
the control device is configured to respectively set, when the battery is not connected to the connecting portion, the first protection device to the charging inhibited state and the second protection device to the charging permitted state, and thereafter switch, when the voltage value of the charging path detected by the voltage detection device is equal to or greater than a predetermined specified voltage value, the second protection device to the charging inhibited state.

2. The charger according to claim 1 , further comprising:
a display unit configured to display a state of the charger,
wherein the control device is configured to display, in a case where the control device switches the second protection device to the charging inhibited state when the battery is not connected to the connecting portion, an abnormality on the display unit when the battery is thereafter connected to the connecting portion.

3. The charger according to claim 1 , further comprising:
a current detection device configured to detect a current value flowing through the charging path,
wherein the control device is configured to respectively set, when the battery is connected to the connecting portion and charging of the battery by the charging device has been completed, the first protection device to the charging inhibited state and the second protection device to the charging permitted state, and thereafter switch, when the current value detected by the current detection device exceeds a predetermined specified current value, the second protection device to the charging inhibited state.

4. The charger according to claim 1 , wherein
each of the two protection devices includes a photo coupler configured to be brought into a conductive state by a light entering from a light emitting device into a light receiving device,
the first protection device is configured such that the light emitting device of the photo coupler emits a light when the first protection device is in the charging permitted state, and
the second protection device is configured such that the light emitting device of the photo coupler emits a light when the second protection device is in the charging inhibited state.

5. The charger according to claim 1 , wherein
the two protection devices include two switches provided in series in the charging path and configured to open and close the charging path, one switch of the two switches corresponding to the first protection device and the other switch of the two switches corresponding to the second protection device,
the one switch includes a normally open switch configured to be brought into a closed state by electric conduction, and
the other switch includes a normally closed switch configured to be brought into an open state by electric conduction.

Assignees

• Makita Corp

Inventors

• Ishikawa Yoshihiro

Classifications

• H02J7/663

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• H02J7/685

  using connection detecting circuits (H02J7/68 takes precedence) · CPC title

• H02J7/80

  including monitoring or indicating arrangements · CPC title

• H02J7/62

  against overcurrent · CPC title

• H02J7/61

  against overcharge · CPC title