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.

A vehicle-mounted electric oil-free air compressor, including a motor, a box body, a piston, and a flywheel shaft. The motor is fixed on the box body, a cylinder cover is at the top of the box body, a main shaft of the motor includes a coupling driving end, the flywheel shaft is driven by an elastic body to rotate. The piston includes a primary intake valve piece and a primary exhaust valve piece, the box body is provided with a secondary cavity, a secondary exhaust valve piece is provided at a vent hole on one side of the cavity, and the primary exhaust valve piece is also a secondary intake valve piece of the compressor, increasing the exhaust pressure. When the piston reciprocates, the stress is balanced and the vibration is small, and with the assistance of a high-efficiency flywheel, the operation of the air compressor is stable.

A three-stage compression air pump includes a pump head and a pumping device. The pumping device includes first and second cylinders and a plunger. The first cylinder is connected with the pump head and coupled to a first piston moving in the second cylinder. The second cylinder includes a first end cap and a second end cap respectively coupled to the two ends thereof The first cylinder is inserted through the first end cap. The second end cap defines an orifice allowing outside air to flow into the second cylinder and includes a one-way valve preventing the air in the second cylinder from flowing outside the three-stage compression pump. The plunger is inserted in and movably coupled to the first cylinder and coupled to a second piston moving in the first cylinder and connected with the second end cap. The plunger is inserted through the first piston.

Disclosed embodiments include a reconfigurable multi-stage gas compressor having a first-stage compression cylinder, a second-stage compression cylinder, and two stepped cylinders. Each of the stepped cylinders include first and second compression cylinders. The gas flow paths through the stepped cylinders are configured in a user-selectable configuration to be in series or in parallel so that the reconfigurable multi-stage gas compressor functions as one of: a three-stage compressor, as a four-stage compressor, and as a hybrid three/four stage compressor. In first and second configurations, the system generates four stages of compression and outputs 4-stage compressed gas through a single exit port, and through dual exit ports, respectively. In a third configuration, the system outputs hot and cooled 3-stage compressed gas through first and second ports and 4-stage compressed gas through a third port. In a fourth configuration, the system outputs hot and cooled 3-stage compressed gas with no 4-stage compressed gas.

A gas compressor, wherein the gas compressor can be used for compressing gas, vapor, or combinations thereof. The gas compressor includes a drive power section and a dual activating compressor section. The gas compressor can be used in a system for compressing gas, vapor, or combinations thereof.

A variable pressure air pump includes a first cylinder and a second cylinder movable relative to the first cylinder along a longitudinal axis. An air tube is mounted in the first and second cylinders. A mounting portion is integrally formed on a first end of the air tube. A first piston and a second piston compress air in the first and second cylinders. A connecting device is mounted to the first cylinder for coupling with an object to be inflated. An air escape device selectively seals a second chamber of the second cylinder to selectively compress the air in the second cylinder. A first check valve is mounted to the mounting portion of the air tube. A second check valve is mounted to the second piston.

A variable pressure air pump includes a first cylinder and a second cylinder movable relative to the first cylinder along a longitudinal axis. An air tube is mounted in the first and second cylinders. A mounting portion is integrally formed on a first end of the air tube. A first piston and a second piston compress air in the first and second cylinders. A connecting device is mounted to the first cylinder for coupling with an object to be inflated. An air escape device selectively seals a second chamber of the second cylinder to selectively compress the air in the second cylinder. A first check valve is mounted to the mounting portion of the air tube. A second check valve is mounted to the second piston.

An air pump includes a mouthpiece, an adjustment mechanism, and an air cylinder mechanism that includes a small-diameter cylinder permitted to move relative to the adjustment mechanism. When the small-diameter cylinder is moved away from the adjustment mechanism, air from external environment is sucked into a first space of the air cylinder mechanism. The adjustment mechanism is operable to switch between a singular pumping state, where air in the first space is released to the external environment when the small-diameter cylinder is moved toward the adjustment mechanism, and a dual pumping state, where the air in the first space is injected into the mouthpiece when the small-diameter cylinder is moved toward the adjustment mechanism.

An air pump includes a mouthpiece, an adjustment mechanism, and an air cylinder mechanism that includes a small-diameter cylinder permitted to move relative to the adjustment mechanism. When the small-diameter cylinder is moved away from the adjustment mechanism, air from external environment is sucked into a first space of the air cylinder mechanism. The adjustment mechanism is operable to switch between a singular pumping state, where air in the first space is released to the external environment when the small-diameter cylinder is moved toward the adjustment mechanism, and a dual pumping state, where the air in the first space is injected into the mouthpiece when the small-diameter cylinder is moved toward the adjustment mechanism.

The present application discloses a compressor including a crank shaft, a first reciprocation converter, a first cylinder body, a first pressurizing portion, a second reciprocation converter, which is connected to the crank shaft with a phase different by 180 degrees from the first reciprocation converter, a second cylinder body, a second pressurizing portion, and a connecting portion configured to interconnect the compression chambers. The compression chambers are arranged so that a timing at which the gas is discharged from a specific compression chamber among the compression chambers becomes the same as a timing at which the discharged gas is suctioned into another compression chamber at a higher side by one stage than the specific compression chamber.