A method for dispensing a product from an interior volume of a container to which a power assembly is secured, which includes rotating an actuator sleeve of the power assembly in one direction relative to the container to draw an amount of the product from the interior volume into a pump chamber and to pressurize the pump chamber, and temporarily depressing an actuator of the power assembly to dispense a portion of the product from the pump chamber through a nozzle for a duration of time during which the actuator is temporarily depressed. During the duration when the product is dispensed from the container, the power assembly does not rotate relative to the container, and the power assembly is never rotated in an opposite direction.

The present invention is directed to a minimum pressure valve comprising a housing (13) with a valve inlet (11) and a valve outlet (12) which are connected by means of a chamber (16), said minimum pressure valve (10) further comprising a valve body (17) movable in said chamber (16) between a closed position in which said valve inlet (11) is closed off, and an open position in which said valve inlet (11) is open, whereby said minimum pressure valve (10) further comprises a regulation unit (18) for setting the value of the pressure at which the valve body (17) moves into an open position.

The present invention is directed to a minimum pressure valve comprising a housing (13) with a valve inlet (11) and a valve outlet (12) which are connected by means of a chamber (16), said minimum pressure valve (10) further comprising a valve body (17) movable in said chamber (16) between a closed position in which said valve inlet (11) is closed off, and an open position in which said valve inlet (11) is open, whereby said minimum pressure valve (10) further comprises a regulation unit (18) for setting the value of the pressure at which the valve body (17) moves into an open position.

The discharge valve arrangement (17) includes a valve plate (18) including a discharge passage (22) and a valve seat (23) surrounding the discharge passage (22); a valve housing (24) being secured to the valve plate (18) and including a bottom portion (25) facing away from the valve plate (18), a sidewall (26) extending from the bottom portion (25) and towards the valve plate (18), and a discharge opening (28) formed in the sidewall (26); a valve member (31) displaceable between a closed position in which the valve member (31) closes the discharge passage (22) and an open position in which the valve member (31) opens the discharge passage (22). The valve housing (24) includes a gas damping chamber defined by the bottom portion (25) and the sidewall (26) and being configured to accommodate the valve member (31) in the open position; and an exhaust opening (37) formed in the bottom portion (25) and emerging in the gas damping chamber.

The discharge valve arrangement (17) includes a valve plate (18) including a discharge passage (22) and a valve seat (23) surrounding the discharge passage (22); a valve housing (24) being secured to the valve plate (18) and including a bottom portion (25) facing away from the valve plate (18), a sidewall (26) extending from the bottom portion (25) and towards the valve plate (18), and a discharge opening (28) formed in the sidewall (26); a valve member (31) displaceable between a closed position in which the valve member (31) closes the discharge passage (22) and an open position in which the valve member (31) opens the discharge passage (22). The valve housing (24) includes a gas damping chamber defined by the bottom portion (25) and the sidewall (26) and being configured to accommodate the valve member (31) in the open position; and an exhaust opening (37) formed in the bottom portion (25) and emerging in the gas damping chamber.

A method for expanding a compressed gas (GD) at a gas pressure (pD) with a reciprocating-piston machine, wherein the reciprocating-piston machine includes a piston that can move to and fro and a working chamber delimited by the movable piston. The method being carried out as follows: the compressed gas (GD) is supplied to the working chamber via an actuatable rotary slide valve, wherein the compressed gas (GD) in the working chamber is expanded in the working chamber.

A method for expanding a compressed gas (GD) at a gas pressure (pD) with a reciprocating-piston machine, wherein the reciprocating-piston machine includes a piston that can move to and fro and a working chamber delimited by the movable piston. The method being carried out as follows: the compressed gas (GD) is supplied to the working chamber via an actuatable rotary slide valve, wherein the compressed gas (GD) in the working chamber is expanded in the working chamber.

Pumps for noncontact tonometry are provided. In one embodiment, a pump for noncontact tonometry includes a compression pump, a compression chamber, a first pressure sensor in communication with the compression chamber, a surge chamber, and a valve separating the compression chamber and surge chamber. The compression pump compresses a first volume of gas into the compression chamber. When the first pressure sensor detects a threshold pressure in the compression chamber, the valve opens and releases the gas into a surge chamber, where it combines with a gas residing in the surge chamber to form a puff of gas that escapes from the surge chamber through a flow-limiting nozzle. The components of the pump, which relies on passive rather than active components to create the controlled puff, can be assembled to have a profile that is portable and fit for home use.

An air compressor apparatus is disclosed that includes an air tank. A first compressor assembly can be fluidly coupled to the air tank, the first compressor assembly including a first head unloader valve. A second compressor assembly can be fluidly coupled to the air tank, the second compressor assembly including a second head unloader valve. A control unit can be electrically coupled to the first and second compressor assemblies, the control unit operable to control the operation of the first and second compressor assemblies. During startup, the first and second air compressor assemblies can be configured to draw less than 20 amps of current combined from a single 120 volt power source. The first and second compressor assemblies can each be dual piston compressor assemblies.

Various embodiments of the present disclosure are directed to reciprocating compressors. In one example embodiment, a reciprocating compressor is disclosed including a cylinder, a piston, at least one suction valve, at least one pressure valve, at least one connection chamber, a sequence valve, a sequence valve control unit, and an unloader. The piston moves back and forth in the cylinder in order to form a compression chamber in the cylinder. The at least one suction valve and the at least one pressure valve are provided on the compression chamber. The at least one connection chamber having a connection chamber volume, which is connected to the compression chamber via at least one overflow opening. The sequence valve opens and closes the at least one overflow opening, and the sequence valve control unit controls the sequence valve. The unloader is actuated by an electrically controllable actuator.