Systems and methods for a compressor system are provided for selectively operating the compressor system with reduced power consumption. An output demand level of the compressor system can be monitored over time to identify a demand profile. A pressure setpoint for the compressor system can be selectively adjusted based on the demand profile, including to selectively transition between an operational pressure setpoint for an active demand profile and a reduced pressure setpoint for an inactive demand profile.

An agricultural work vehicle having an air supply device includes: an air compressor for pressurizing air; an air tank for storing the air compressed by means of the air compressor; a pressure sensor for measuring the pressure of the air stored in the air tank or atmospheric pressure; a controller for stopping the operation of the air compressor when the measured pressure exceeds a first reference value; and an air pressure regulator for discharging, to the outside, the air inside an air pressure circuit system so as to reduce the pressure when the pressure of the air stored in the air tank exceeds a second reference value.

A built-in air pump comprises a housing body and a panel. The panel couples to the housing body and defines an opening. A main pump body couples to the housing body and defines a first accommodating chamber in fluid communication with the opening and with a first and a second venting port. An air replenishing pump has an air replenishing pump body that is located adjacent to the main pump body. The air replenishing pump body couples to the housing body and defines a second accommodating chamber having therein the air replenishing pump. An air passage switch, located in the first accommodating chamber, is moveable between a first and a second position. A controller is in electrical connection with the air replenishing pump and configured to activate the air replenishing pump based on a time determination. An inflatable body including the built-in air pump assembly is also disclosed herein.

A pump system contains a vibration actuator which can be electromagnetically driven by applying an alternating-current voltage E thereto, a sealed chamber connected to a suction port and a discharge port, and a movable wall for changing a volume of the sealed chamber. The movable wall is displaced due to drive of the vibration actuator to supply fluid in the sealed chamber into a target object. The pump system controls an effective value of the alternating-current voltage E so that an amplitude Y of the vibration actuator is constant.

A hydraulic system comprises a fluid tank and a pump, including a pump reservoir, fluidly coupled to the tank via a supply line. A valve is in fluidic communication with the pump reservoir via a pressure line. A backflow line fluidly couples the pump reservoir to the fluid tank via a timer reservoir and an orifice included in the timer reservoir. The hydraulic system transitions between a normal state and a purge state. In the normal state in which the pump is on, a first portion of the fluid is communicated from the pump reservoir to the valve and a second portion of the fluid is communicated from the pump reservoir to the tank. In the purge state, the pressure line and valve are purged followed by the backflow line and the pump reservoir such that no fluid remains in the pump reservoir.

The purpose of the present invention is to provide a reciprocating compressor which is a compact, light-weight, portable air compressor such that deterioration of performance due to problems such as wear on the surface finish of the cylinder when the compressor is used for a long period of time outside the operating temperature range thereof is prevented. To achieve this, the cylinder temperature is detected, and control is carried out so that the compressor is restarted at a lower restart pressure when the temperature is lower than a prescribed value and stopped (and also restarted, preferably) at a low pressure when the temperature is higher than a prescribed value.

An air compressor includes a tank unit that stores compressed air, a motor unit that generates compressed air to be stored in the tank unit, a pressure detection unit that detects a pressure value in the tank unit, and a control unit that drives the motor unit when a pressure value in the tank unit detected by the pressure detection unit is equal to or less than a motor start pressure value, and stops the motor unit when the pressure value in the tank unit detected by the pressure detection unit is equal to or greater than a motor stop pressure value. The control unit changes at least either of the motor start pressure value or the motor stop pressure value every time when a predetermined time passed.

A gas leak determining method for a multi-stage compressor including: a first compressing unit that compresses a gas; and a second compressing unit that further compresses the gas compressed by the first compressing unit includes: a step of calculating a proportion of discharge pressure from the second compressing unit to discharge pressure from the first compressing unit or suction pressure into the second compressing unit; and a step of determining that a gas is leaking from the second compressing unit when the proportion becomes equal to or less than a set value.

An air compressor includes: a motor actuating a mechanism to generate compressed air; a tank part in which the compressed air is stored; a pressure detector detecting a pressure value in the tank part; and a controller driving the motor when the pressure value is equal to or smaller than an ON pressure value and to stop drive of the motor when the pressure value is equal to or greater than an OFF pressure value. The controller executes processing for detecting a continuous drive time or a continuous stop time of the motor and changing at least one of the ON pressure value, the OFF pressure value and an output of the motor, and the controller detects a change amount of the pressure value, and to determine an execution cycle of the processing or a change amount of a value in the processing, based on the detected change amount.

A compressed air system for a motor vehicle with an air supply system includes an electric drive motor, which can be controlled for variable speed, an air compressor coupled to be driven by the electric drive motor, an electric power supply for supplying electric power to the electric drive motor, at least one air reservoir connected with the air compressor to receive air from the air compressor, an air utilization system connected to the air reservoir to receive air from the air reservoir, and a controller to control the speed of the electric drive motor. The controller controls the electric drive motor to determine its speed depending upon at least one of the following signals: a signal representing the activation status of an accelerator pedal of the vehicle, a signal representing the speed of the vehicle, a signal representing the temperature of the power supply, a signal representing the temperature of the electric drive motor, a signal representing the wetness level of the air compressed by the air compressor, a signal representing the load of the air compressor, a signal representing the running time of the air compressor, or a signal representing the status of the electric power supply.