Abstract: The present disclosure provides a battery pack including a housing, wherein the housing has a bottom portion and side walls extending upward around a periphery of the bottom portion; an upper portion opening is formed at top ends of the side walls extending upward; an upper cover is mounted on the upper portion opening of the housing; and the battery pack comprises: multiple flat battery cells; and a first end plate and a second end plate, wherein when the multiple battery cells are sequentially arranged and mounted into the housing from the upper portion opening, the first end plate and the second end plate are located at two end sides of the sequentially arranged multiple battery cells to laterally fix the sequentially arranged multiple battery cells. The two end plates may absorb deformation of the battery cell while expanding.

Abstract: A leakproof gas-liquid mixing pump has a lower shell body, a pressing member and an upper shell body, the lower shell body has a liquid channel part and an outer shell part, the pressing member has a pressing part, a liquid guiding part and a first spring, the upper shell body surrounds the pressing member and is connected to the outer shell part and the liquid container. The leakproof gas-liquid mixing pump solves the problem that the gas-liquid mixing pump of the state of the art will leak when used upside down.

Abstract: A paper dispenser includes a base, paper dispensing portion and cover. The paper dispensing portion has two support members and a paper dispensing unit. The paper dispensing unit has an auxiliary roller, paper dispensing roller, swing unit and paper dispensing cutter disposed at the swing unit. The paper dispensing cutter swings between the inside and outside of a receiving groove of the paper dispensing roller. The support members each have a roll resilient positioning unit, arcuate pivotal connection unit and cam guide groove surrounding the pivotal connection unit and being closed. Two sides of the paper dispensing roller are pivotally disposed at one end of the pivotal connection unit. The guide unit is movably disposed at the cam guide groove. The cover is pivotally disposed at the base and has a paper discharge hole. The paper dispensing portion is disposed between the cover and base.

Abstract: A directional gear is adapted to be fitted to a driving shaft and includes a driving element, an external gear and a plurality of catching elements. The driving element is fitted to the driving shaft. A plurality of receiving slots are disposed at the periphery of the driving element. The external gear is disposed radially outside the driving element and includes a ring-shaped body and a plurality of tilted inner teeth. The tilted inner teeth are connected to the inner side of the ring-shaped body. The catching elements are movably disposed in the receiving slots and each include a catching portion corresponding in shape to the corresponding tilted inner teeth. The catching elements are selectively engaged with at least one of the tilted inner teeth of the external gear through the catching portions.

Abstract: A directional gear is adapted to be fitted to a driving shaft and includes a driving element, an external gear and a plurality of catching elements. The driving element is fitted to the driving shaft. A plurality of receiving slots are disposed at the periphery of the driving element. The external gear is disposed radially outside the driving element and includes a ring-shaped body and a plurality of tilted inner teeth. The tilted inner teeth are connected to the inner side of the ring-shaped body. The catching elements are movably disposed in the receiving slots and each include a catching portion corresponding in shape to the corresponding tilted inner teeth. The catching elements are selectively engaged with at least one of the tilted inner teeth of the external gear through the catching portions.