Abstract: A charging and discharging device includes a transformer consisting of a primary winding and multiple secondary windings including at least a first secondary winding and a second secondary winding; multiple ports electrically connected to the primary winding and the multiple secondary windings of the transformer, respectively, wherein the multiple ports at least include a first port electrically connected to the primary winding via a first conversion circuit; a second port electrically connected to the first secondary winding via a second conversion circuit; and a third port electrically connected to the second secondary winding via a third conversion circuit; and a first controllable switch connected between the first conversion circuit and the primary winding.

Abstract: The utility model relates to a display means of digital level. Said digital level is provided with one notch in basal body, where said display lies. Two ends of said display are provided with two center-axles that lie in the same axis line of rotation, and two sidewalls of said notch are provided with two center-axle-holes, wherein said display is rotatablely connected with said basal body of digital level by inserting said two center-axles into said two center-axle-holes. Said display of this utility model is rotatable, so in practical application, user can locate this display on the desired position, thus to read the value shown thereon conveniently. Moreover, the positioning and position restriction to the rotation of said display could suit many conveniences for users to read the value shown thereon.

Abstract: The utility model relates to a display means of digital level. Said digital level is provided with one notch in basal body, where said display lies. Two ends of said display are provided with two center-axles that lie in the same axis line of rotation, and two sidewalls of said notch are provided with two center-axle-holes, wherein said display is rotatablely connected with said basal body of digital level by inserting said two center-axles into said two center-axle-holes. Said display of this utility model is rotatable, so in practical application, user can locate this display on the desired position, thus to read the value shown thereon conveniently. Moreover, the positioning and position restriction to the rotation of said display could suit many conveniences for users to read the value shown thereon.

Abstract: A laser marking device including an oscillating mechanism that enables the laser beams emitted from the device to be emitted in either a constant state or in a pulsed state to enhance the visibility of the laser beam in various lighting conditions. The oscillating mechanism modulates the power supplied by the power source into either a constant state or a pulsed state in order to send the power in that state to the laser generator, which consequently emits a laser beam in either a constant or pulsed state. In bright light conditions in which the beam is not readily visible, the beam can be emitted in a pulsed state to be sensed by a separate detector capable of detecting the pulsed beam from the device. The detector provides an indication to the operator of the position of the beam relative to the detector such that the operator can readily determine the location of the beam.

Abstract: A laser marking device including an oscillating mechanism that enables the laser beams emitted from the device to be emitted in either a constant state or in a pulsed state to enhance the visibility of the laser beam in various lighting conditions. The oscillating mechanism modulates the power supplied by the power source into either a constant state or a pulsed state in order to send the power in that state to the laser generator, which consequently emits a laser beam in either a constant or pulsed state. In bright light conditions in which the beam is not readily visible, the beam can be emitted in a pulsed state to be sensed by a separate detector capable of detecting the pulsed beam from the device. The detector provides an indication to the operator of the position of the beam relative to the detector such that the operator can readily determine the location of the beam.