Abstract: A mold structure and the replacement method thereof. The mold structure has a lower molding plate, at least one lower die core, a plurality of lower supporters, a plurality of first positioning units, an upper molding plate, at least one upper die core, a plurality of upper supporters and a plurality of merging units. The upper die core and the lower die core are passed through by a plurality of fasteners, and fixed on the upper molding plate and the lower molding plate respectively. The upper supporters and the lower supporters are disposed around the upper die core and the lower die core respectively, and passed through by a plurality of fasteners to fix them on the upper molding plate and the lower molding plate respectively. A part of a first positioning unit protruding out of a lower supporter is inserted into a merging unit. The present invention provides an accurate way to fix die cores, improves procedures in conventional molding, further reduces process time and saves cost.

Abstract: The present application discloses a device, method and system for controlling a rotation speed of a motor. The device includes: a reference voltage generating module generating a reference voltage; a PWM signal converting module converting a PWM signal into a voltage signal; a first comparator outputting a first level or a second level; a first switching element having a control terminal connected with an output terminal of the first comparator and a first terminal input with a first signal, and being turned on when receiving the second level and being turned off when receiving the first level; a follower having an input terminal connected with the PWM signal converting module; and a control signal outputting terminal outputting the first signal or the voltage signal. The device, method and system are capable of controlling the rotation speed of the motor to jump at a specific duty cycle.

Abstract: The present application discloses a device, method and system for controlling a rotation speed of a motor. The device includes: a reference voltage generating module generating a reference voltage; a PWM signal converting module converting a PWM signal into a voltage signal; a first comparator outputting a first level or a second level; a first switching element having a control terminal connected with an output terminal of the first comparator and a first terminal input with a first signal, and being turned on when receiving the second level and being turned off when receiving the first level; a follower having an input terminal connected with the PWM signal converting module; and a control signal outputting terminal outputting the first signal or the voltage signal. The device, method and system are capable of controlling the rotation speed of the motor to jump at a specific duty cycle.