ADAPTER AND ELECTRIC POWER TOOL

• US 20140042981A1
• Filed: 08/08/2013
• Published: 02/13/2014
• Est. Priority Date: 08/09/2012
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: KAIZO, Hiroyuki, ARIMURA, Tadashi, OHASHI, Toshiharu
• Granted Patent: US 9,472,969 B2
• Time in Patent Office: Days
• US Class Current: 320/136
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00304 Overcurrent protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators

Abstract

An adapter includes a converter unit which increases at least one of voltage and current outputted from a battery pack and supply the increased the voltage and/or the current to a load, and a characteristic detection unit which detects at least one of the voltage outputted from the battery pack, the current outputted from the battery pack, a temperature of the battery pack, a voltage inputted to the load, a current inputted to the load and a temperature of the converter unit. The adapter further includes a control unit configured to control the converter unit to increase each of said at least one of the voltage and the current outputted from the battery pack to a corresponding reference value and perform a control operation of suppressing such increase to prevent an occurrence of over-current or over-discharge based on at least one detection result.

Claims

1. An adapter, comprising:

a converter unit configured to increase at least one of a voltage and a current outputted from a battery pack and supply the increased at least one of the voltage and the current to a load;

a characteristic detection unit configured to detect at least one of the voltage outputted from the battery pack, the current outputted from the battery pack, a temperature of the battery pack, a voltage inputted to the load, a current inputted to the load and a temperature of the converter unit; and

a control unit configured to control the converter unit to increase each of said at least one of the voltage and the current outputted from the battery pack to a corresponding reference value and further perform a control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent an occurrence of over-current or over-discharge based on at least one detection result detected by the characteristic detection unit.

2. The adapter of claim 1, wherein the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit within a range equal to or smaller than the corresponding reference value to prevent the occurrence of over-current or over-discharge based on said at least one detection result.

3. The adapter of claim 1, wherein the characteristic detection unit is configured to detect the voltage inputted to the load, and

wherein the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-current or over-discharge based on the detected voltage.

4. The adapter of claim 1, wherein the characteristic detection unit is configured to detect the voltage outputted from the battery pack, and

wherein the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-current or over-discharge based on the detected voltage.

5. The adapter of claim 1, wherein the characteristic detection unit is configured to detect one of the current inputted to the load and the current outputted from the battery pack, and

wherein the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-current or over-discharge based on the detected current.

6. The adapter of claim 1, wherein the characteristic detection unit is configured to detect one of the temperature of the battery pack and the temperature of the converter unit, and

wherein the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-current or over-discharge based on the detected temperature.

7. The adapter of claim 1, wherein the characteristic detection unit is configured to detect at least two of the voltage outputted from the batter pack, the current outputted from the battery pack, the temperature of the battery pack, the voltage inputted to the load, the current inputted to the load and the temperature of the converter unit, and

wherein the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-current or over-discharge based on at least two detection results detected by the characteristic detection unit.

8. The adapter of claim 1, wherein the characteristic detection unit is configured to detect one of the current outputted from the battery pack and the current inputted to the load, and one of the voltage outputted from the battery pack and the voltage inputted to the load, and

wherein, when the detected current reaches a reference current value and the detected voltage becomes equal to or smaller than a reference voltage value, the control unit stops the converter unit and allows the voltage supplied from the battery pack to be supplied to the load.

9. The adapter of claim 1, further comprising:

a storage unit in which temperatures of the battery pack and reference currents corresponding to the temperatures of the battery pack are stored,

wherein the characteristic detection unit is configured to detect the temperature of the battery pack and the current outputted from the battery pack, and

wherein, by referring to a reference current corresponding to the detected temperature of the battery pack, the control unit compares the detected current with the reference current, and performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit when the detected current is higher than the reference current.

10. The adapter of claim 1, wherein the control unit has a first over-current threshold and a second over-current threshold larger than the first over-current threshold,

wherein, when a detection result reaches the first over-current threshold, the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-current, and

wherein, when the detection result reaches the second over-current threshold, the control unit stops the operation of the load.

11. The adapter of claim 1, wherein the control unit has a first over-discharge threshold and a second over-discharge threshold smaller than the first over-discharge threshold,

wherein, when a detection result reaches the first over-discharge threshold, the control unit performs the control operation of suppressing the increase of said at least one of the voltage and the current in the converter unit to prevent the occurrence of over-discharge, and

wherein, when the detection result reaches the second over-discharge threshold, the control unit stops the operation of the load.

12. An electric power tool comprising:

the adapter described in claim 1;

the battery pack; and

a tool body having the load.

13. The electric power tool of claim 12, wherein the adapter is configured to be provided in the tool body.

14. The electric power tool of claim 12, wherein the adapter is configured to be provided between the tool body and the battery pack.