A trimmer includes a handle assembly, a power mechanism installed at one end of the handle assembly, and a blade assembly connected to the power mechanism. The power mechanism has a housing assembly, a motor received in the housing assembly, and a power transmission assembly mounted on the housing assembly. The motor is an external rotor motor with a diameter greater than or equal to 50 mm. The power transmission assembly has pinion coaxially sleeved on an output shaft of the motor and a big gear meshing with the small gear, and a transmission ratio of the small gear to the big gear is less than 6. By such arrangement, the trimmer can obtain the best output effect under a condition that the output power of the motor is unchanged.

Release mechanism (10) for an electronic locking system (156), wherein the release mechanism (10) is configured such that an input member (14) and an output member (16) are locked against relative rotation and can rotate together within a locking ring opening (22) when a locking member (20) is located in an input member recess (42) and in an output member recess (46), and such that the output member (16) is released to rotate relative to the input member (14) when the locking member (20) is located in the output member recess (46) and in a locking ring recess (26). A freewheel mechanism (66) and assemblies (98) for an electronic locking system (156) are also provided.

Release mechanism (10) for an electronic locking system (156), wherein the release mechanism (10) is configured such that an input member (14) and an output member (16) are locked against relative rotation and can rotate together within a locking ring opening (22) when a locking member (20) is located in an input member recess (42) and in an output member recess (46), and such that the output member (16) is released to rotate relative to the input member (14) when the locking member (20) is located in the output member recess (46) and in a locking ring recess (26). A freewheel mechanism (66) and assemblies (98) for an electronic locking system (156) are also provided.

A flywheel assembly for a renewable energy generation system includes a flywheel housing defining a cavity therein, a flywheel rotatably disposed within the cavity of the flywheel housing, where the flywheel is simultaneously formed from the same component as the flywheel housing, a magnetic levitation disk defining opposed upper and lower surfaces, the upper surface supporting the flywheel and the lower surface including a first plurality of magnets disposed thereon, and a base plate having a second plurality of magnets disposed on a surface thereof that is facing the first plurality of magnets, the second plurality of magnets having a polarity that is opposite of a polarity of the first plurality of magnets such that the magnetic force of the first and second plurality of magnets urges the magnetic levitation disk away from the base plate.

A flywheel assembly for a renewable energy generation system includes a flywheel housing defining a cavity therein, a flywheel rotatably disposed within the cavity of the flywheel housing, where the flywheel is simultaneously formed from the same component as the flywheel housing, a magnetic levitation disk defining opposed upper and lower surfaces, the upper surface supporting the flywheel and the lower surface including a first plurality of magnets disposed thereon, and a base plate having a second plurality of magnets disposed on a surface thereof that is facing the first plurality of magnets, the second plurality of magnets having a polarity that is opposite of a polarity of the first plurality of magnets such that the magnetic force of the first and second plurality of magnets urges the magnetic levitation disk away from the base plate.

Release mechanism for an electronic locking system, wherein the release mechanism is configured such that an input member and an output member are locked against relative rotation and can rotate together within a locking ring opening when a locking member is located in an input member recess and in an output member recess, and such that the output member is released to rotate relative to the input member when the locking member is located in the output member recess and in a locking ring recess. A freewheel mechanism and assemblies for an electronic locking system are also provided.

Release mechanism for an electronic locking system, wherein the release mechanism is configured such that an input member and an output member are locked against relative rotation and can rotate together within a locking ring opening when a locking member is located in an input member recess and in an output member recess, and such that the output member is released to rotate relative to the input member when the locking member is located in the output member recess and in a locking ring recess. A freewheel mechanism and assemblies for an electronic locking system are also provided.

A driving and resistance control system for a permanent-magnet synchronous motor is disclosed. A control device includes a processing unit, a motor driving circuit, a resistance controller, and an interlock switch. In a first operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor open-circuiting, and connecting stator windings of the permanent-magnet synchronous motor to the resistance controller, and under this condition, the external rotor of the permanent-magnet synchronous motor is rotated by spinning of a flywheel, so that the permanent-magnet synchronous motor is operating in a generator mode to generate a resisting force to the flywheel by mesas of a resistance generation device. In a second operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor closed-circuiting and cutting off control of the resistance controller, and electrical energy is supplied from the power supply circuit to the permanent-magnet synchronous motor, so as to make the permanent-magnet synchronous motor operating in a motor mode to induce an acceleration on the external rotor.

A driving and resistance control system for a permanent-magnet synchronous motor is disclosed. A control device includes a processing unit, a motor driving circuit, a resistance controller, and an interlock switch. In a first operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor open-circuiting, and connecting stator windings of the permanent-magnet synchronous motor to the resistance controller, and under this condition, the external rotor of the permanent-magnet synchronous motor is rotated by spinning of a flywheel, so that the permanent-magnet synchronous motor is operating in a generator mode to generate a resisting force to the flywheel by mesas of a resistance generation device. In a second operation mode, the interlock switch makes the motor driving circuit and the permanent-magnet synchronous motor closed-circuiting and cutting off control of the resistance controller, and electrical energy is supplied from the power supply circuit to the permanent-magnet synchronous motor, so as to make the permanent-magnet synchronous motor operating in a motor mode to induce an acceleration on the external rotor.

A kinetic energy recovery system with flywheel includes a cascade flywheel doubly-fed electric machine and an electric motor. The cascade flywheel doubly-fed electric machine has a stator end coil, a rotor end coil and a flywheel. The flywheel can store kinetic energy by increasing speed or releasing kinetic energy by decreasing speed. A control circuit has an inverter, a rectifier and a DC bus connecting the inverter and the rectifier. The inverter supplies alternating current to the rotor end coil. The rectifier has an AC end connected to the stator end coil through an AC bus. The rectifier converts alternating current to direct current, so that the inverter can draw power from the DC bus. The electric motor has a phase coil connected to the AC bus. When the cascade flywheel double-fed electric machine decelerates, the system converts mechanical energy into electrical energy.