Blowers with variable nozzles are provided. A blower includes a fan, and a main body housing the fan, the main body defining an airflow path extending between an inlet end and an outlet end. A blower further includes a variable nozzle disposed at the outlet end. The variable nozzle includes an attachment collar, the attachment collar comprising a body defining an exterior surface and an interior surface and extending along a longitudinal axis. The variable nozzle further includes a plurality of air control bodies, each of the plurality of air control bodies movably connected to the attachment collar and comprising an air control surface and an extension rod. The variable nozzle further includes an adjustment collar, the adjustment collar disposed around the attachment collar and defining a plurality of adjustment channels, wherein each of the plurality of extension rods is disposed in one of the plurality of adjustment channels.

A method for mitigating water invasion to a submersible motor includes: forming an accumulation zone within an inner space of the submersible motor, wherein the accumulation zone is disposed at a bottom of the inner space below a motor shaft; measuring a conductivity of a fluid inside the accumulation zone using a sensor, wherein the fluid comprises water and dielectric oil; comparing the conductivity of the fluid with a threshold value; upon detecting that the conductivity of the fluid is greater than the threshold value, activating a solenoid pump to discharge the fluid from the accumulation zone to an outside of the submersible motor.

A method for mitigating water invasion to a submersible motor includes: forming an accumulation zone within an inner space of the submersible motor, wherein the accumulation zone is disposed at a bottom of the inner space below a motor shaft; measuring a conductivity of a fluid inside the accumulation zone using a sensor, wherein the fluid comprises water and dielectric oil; comparing the conductivity of the fluid with a threshold value; upon detecting that the conductivity of the fluid is greater than the threshold value, activating a solenoid pump to discharge the fluid from the accumulation zone to an outside of the submersible motor.

A cascade extension device and a cascade system having the cascade extension device are provided. The cascade extension device includes a control module, a buffer module, a storage module, and a selecting output module. The cascade system includes a processor and a plurality of extension devices. The processor may simultaneously control the plurality of extension devices through judging the data packet received as a write command, a read command, or a bypass command by a plurality of extension devices.

A compressor that vibrates a rotary shaft or changes an operating frequency of a motor, in response to a vibration frequency of a discharge passage falling outside of a normal range. The compressor may include one or more impeller configured to draw in and compress refrigerant; a motor configured to rotate the one or more impeller; a rotary shaft, to which the one or more impeller and the motor are coupled; at least two thrust bearings that limit vibration of the rotary shaft; a vibration measuring sensor configured to measure a vibration frequency of a discharge passage; and a controller configured to control the at least two thrust bearings based on the vibration frequency. Upon determining that the vibration frequency falls outside of a normal vibration frequency range, the controller controls the at least two thrust bearings to vibrate the rotary shaft a predetermined number of times.

A system and a method for automatically correcting a rotational speed of a motor of a fan are provided. After the fan is moved from an open space to a closed space, a sample and hold circuit samples and holds working periods of a driving signal by which the motor is driven to rotate at a first rotational speed as a first sampled working period, and a working period of a driving signal by which the motor is driven to rotate at a second rotational speed. An arithmetic circuit calculates a difference between the first sampled working period and a first reference working period, and a difference between the second sampled working period and a second reference working period. The arithmetic circuit calculates other working periods of driving signals by which the motor is driven to rotate at other rotational speeds based on the differences.

A system for controlling thermal comfort in a space is provided with a variable mode of operation. The system may include a conditioner for conditioning air in the space, and a sensor for measuring a temperature in the space. A controller is provided for controlling the conditioner based on the temperature sensed by the sensor, and a fan for circulating air within the space is regulated based on the temperature sensed by the sensor. A related system for controlling a fan based on height is also provided, as is a system and method for easily and efficiently determining the height of a fan using a simple camera, such as one on a “smart” phone. A further aspect pertains to a controller, such as for example a portable handheld device, having a user interface adapted for suggesting an increase in a set point temperature of a thermostat based on the selected speed of the fan.

A necklace-type fan includes: a necklace part which has a curved tube shape, and has a plurality of wind blowing holes formed in a longitudinal direction of the necklace part; a wind generation part which has an interior being in communication with the necklace part, and has a fan installed to pump the wind into the necklace part; and a control unit which adjusts a rotational speed of the fan, wherein the wind introduced through the wind generation part is discharged through the wind blowing holes while being changed in intensity by the control unit.

An air conditioning apparatus includes an electric compressor, an inverter, a temperature detection element, and an ECU. The electric compressor compresses a refrigerant drawn from a refrigerant intake port and discharges the refrigerant from a refrigerant discharge port. The inverter is integrated with the electric compressor so as to be cooled by the drawn refrigerant, and operates the electric compressor according to a control signal. The temperature detection element detects a temperature of the inverter. The ECU outputs a control signal to control the inverter. The ECU performs any one or both of a control for reducing a self-cooling amount of the electric compressor and a control for increasing a self-heat generation amount of the inverter with respect to the inverter when the temperature detected by the temperature detection element is lower than a predetermined reference temperature.

Systems and methods for controlling stators of a compressor of a gas turbine engine are provided. The stators and rotatable blades may be included in a stage of the compressor. The rotatable blades may be configured to rotate about an axial axis of the compressor, and each of the stators is rotatable about a corresponding vane axis that extends radially outward from the axial axis of the compressor. Electric motors may be coupled to the stators, where each of the electric motors is configured to individually rotate a corresponding one of the stators in the compressor. A motor controller may be configured to cause the electric motors to rotate the stators in unison or individually.