Abstract: A small-size axial powder feeding inner hole plasma spraying gun comprises a nozzle with one end fixed on one side of a front gun body through a nozzle gland and the other end extending to the other side of the front gun body; an insulator arranged between the front gun body and a rear gun body; a powder feeding frame fixedly connected to the rear gun body internally provided with a powder inlet channel, a cathode seat of a cathode being connected to the powder feeding joint, a cathode head extending into a spray hole channel of the nozzle, and an annular cavity being formed between the cathode head and an inner wall of the spray hole channel; an air inlet channel arranged on the front gun body and communicated with the annular cavity; and a cooling channel with an interior introduced with cooling water.

Abstract: The disclosure discloses a preparation method of a composite coating for a resin matrix composite, comprising the following steps: preparing ceramic-resin composite powders which comprise Al2O3 ceramic, a thermosetting resin and a curing agent and are semi-thermosetting resin powders; and respectively spraying pure Al2O3 ceramic powders and the composite powders on the surface of the resin matrix composite by supersonic atmospheric plasma spraying to form a ceramic-resin composite coating, wherein the pure Al2O3 ceramic powders are fed into jet flow in a manner of feeding powder inside a spray gun, and the composite powders are fed into jet flow in a manner of feeding powder outside the spray gun. Correspondingly, the disclosure also provides a preparation device of a composite coating for a resin matrix composite.

Abstract: Disclosed is an uninterrupted power supply apparatus, comprising a rectifying unit outputs a positive half-cycle of voltage potential and a negative half-cycle of voltage potential; a backup battery outputs a backup voltage; a first boost unit receives the positive half-cycle of voltage potential or the backup voltage and outputs a first voltage; a second boost unit receives the negative half-cycle of voltage potential or the backup voltage and outputs a second voltage; a current shunt unit receives the first voltage and the second voltage and outputs an AC output voltage; a charge circuit, coupled to the rectifying unit, the backup battery, and the first and/or the second boost unit, for being capable of controlling the first and/or the second boost unit to either store a charging power or charge the backup battery by applying the stored charging power alternatively and successively.

Abstract: Disclosed is an uninterrupted power supply apparatus, comprising a rectifying unit outputs a positive half-cycle of voltage potential and a negative half-cycle of voltage potential; a backup battery outputs a backup voltage; a first boost unit receives the positive half-cycle of voltage potential or the backup voltage and outputs a first voltage; a second boost unit receives the negative half-cycle of voltage potential or the backup voltage and outputs a second voltage; a current shunt unit receives the first voltage and the second voltage and outputs an AC output voltage; a charge circuit, coupled to the rectifying unit, the backup battery, and the first and/or the second boost unit, for being capable of controlling the first and/or the second boost unit to either store a charging power or charge the backup battery by applying the stored charging power alternatively and successively.