Patent Application
20070159132
1. Field of the Invention
The present invention relates generally to a battery charger and more particularly, to such a battery charger that is to be used in a motor vehicle to charge the battery pack of a power hand tool.
2. Description of the Related Art
Various battery-operated power hand tools are commercially available. When the battery power of the battery pack of a power hand tool is low, the battery pack must be charged to the saturated status. When charging the battery pack of a power hand tool outdoors, the user may directly install the battery charger in the power socket for cigarette lighter of a motor vehicle to obtain the necessary working voltage from the car battery.
A conventional battery charger for charging a battery pack for power hand tool is known comprising a housing, which defines an accommodation chamber for receiving the battery pack to be charged, a connector fixedly provided at one end of the housing, a charging unit mounted inside the housing and electrically connected to the connector for charging the battery pack inserted into the accommodation chamber of the housing. According to this design, the user cannot adjust the angular position of the housing relative to the connector. After installation of the battery charger in the power socket for cigarette lighter in a motor vehicle, the gearshift lever of the motor vehicle may interfere with the insertion of the battery pack into the accommodation chamber of the housing.
The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a battery charger, which can be adjusted to different installation angles to prevent interference of the gearshift lever when installed in the power socket for cigarette lighter in a motor vehicle for charging a battery pack for power hand tool.
To achieve this object of the present invention, the battery charger for use in a vehicle for charging a battery pack of a power hand tool comprises a first housing, a second housing, a charging unit, a fastening device and a spring member. The first housing has an accommodation chamber for receiving a battery pack, a coupling portion, and a positioning portion provided at the coupling portion. The second housing has a connector electrically connectable to a power socket of a vehicle, a coupling portion pivotally coupled to the coupling portion of the first housing for allowing biasing of the second housing relative to the first housing, and a positioning portion. The charging unit is mounted in one of the first housing and the second housing for charging the battery pack accommodated in the accommodation chamber. The charging unit comprises a circuit board provided with a charging circuit, and a set of contact terminals electrically connected to the charging circuit and protruding into the accommodation chamber for the contact of the electrodes of the battery pack inserted into the accommodation chamber. The fastening device is mounted in the connection point between the coupling portion of the first housing and the coupling portion of the second housing and provided with a positioning portion movably coupled to the positioning portion of the second housing, and an engagement portion. The fastening device is movable between a first position where the engagement portion is engaged with the positioning portion of the first housing to lock the second housing to the first housing for prohibiting biasing of the second housing relative to the first housing and a second position where the engagement portion is disengaged from the positioning portion of the first housing for allowing biasing of the second housing relative to the first housing. The spring member is stopped between the first housing and the fastening device to support the fastening device in the first position.
As shown in
The first housing 20 comprises two half shells 21a and 21b. The two half shells 21a and 21b are abutted against each other and affixed together with screws 22, such that an accommodation chamber 23 is defined therein for accommodating a battery pack 24 for power hand tool to be charged. After insertion of a battery pack 24 into the accommodation chamber 23, a part of the inserted battery pack 24 exposes to the outside of the first housing 20. The two half shells 21a and 21b each have an elongated locating groove 25 corresponding to each other, a coupling portion 26a or 26b at one end, namely, the front end. The coupling portion 26a of one half shell 21a has a through hole 262. The coupling portion 26b of the other half shell 21b has a positioning portion 264. According to this embodiment, the positioning portion 264 comprises a plurality of rectangular locating slots 266 radially arranged in communication with one another.
The charging unit 30 can be installed in the first housing 20 or the second housing 40. According to this embodiment, the charging unit 30 is provided inside the first housing 20. The charging unit 30 comprises a circuit board 32 provided with a charging circuit (not shown) and fastened to the elongated locating grooves 25 in the two half shells 21a and 21b of the first housing 20, and a set of contact terminals 34 electrically connected to the charging circuit of the circuit board 32 and projecting into the accommodation chamber 23 of the first housing 20 for the contact of the electrodes of the battery pack 24 that is inserted into the accommodation chamber 23.
The second housing 40 is comprised of two half shells 41a and 41b. The two half shells 41a and 41b are abutted against each other and fastened together with screws 42 so as to form a front connector 43 insertable into the power socket for cigarette lighter of a motor vehicle. The two half shells 41a and 41b each have a circular-like coupling portion 44a or 44b disposed at the rear side and respectively pivotally coupled to the coupling portions 26a and 26b of the first housing 20, allowing biasing of the second housing 40 relative to the first housing 20 within a predetermined angle. Further, the rectangular locating slots 266 are radially arranged around the pivot point between the coupling portions 40a and 40b of second housing 40 and the coupling portions 26a and 26b of the first housing 20, Further, the coupling portion 44a of one half shell 41a of the second housing 40 has a through hole 441. The coupling portion 44b of the other half shell 41b of the second housing 40 has a positioning portion 443. The positioning portion 443 according to this embodiment comprises a positioning hole 445, which is coaxially disposed in alignment with the through hole 441 and the center of axis of the coupling portions 26a and 26b of the first housing 20, and two locating grooves 447 respectively formed at the top and bottom sides of the annular wall that surrounds the positioning hole 445.
Referring to
The spring member 60 according to this embodiment is a compression coil spring sleeved onto the locating bolt 52 and stopped between a part of the locating bolt 52 and one half shell 21b of the first housing 20. The spring member 60 imparts an outward pressure to the locating bolt 52, supporting the locating bolt 52 in the first position. When moved the locating bolt 52 to the second position, the spring member 60 is compressed.
When wishing to adjust the angular position of the battery charger 10, press the locating bolt 52 against the spring member 60 to move the locating bolt 52 from the first position to the second position and to further disengage the stop block 54 from the locating slots 266 as shown in
As indicated above, the battery charger 10 allows the user to adjust the angular position of the second housing 40 relative to the first housing 20 so that when the connector 43 is connected to the power socket for cigarette lighter in a motor vehicle, the gearshift lever does not interfere with the installation of a battery pack in the battery charger 10 for charging.
Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.
