A method for determining a flow volume of a fluid delivered by a pump. The flow volume is determined as a function of predefined pump information depending on a pump geometry, rotation speed information, which correlates with the rotation speed of the pump, and pressure information, which correlates with a differential pressure at the pump.

In certain examples, a printing system comprises: a depositing system to deposit printing fluid on a print medium; a reservoir; and a displacement pump to move printing fluid to the depositing system from the reservoir. The displacement pump comprises: a pump body defining a chamber, an inlet to fluidly connect the chamber to the reservoir, and an outlet to fluidly connect the chamber to the depositing system; and a displacement member movable relative to the pump body; the displacement member having an outer surface and comprising a cavity located in a portion of the outer surface disposed in the chamber. In use, the displacement member is movable to close the inlet and to force printing fluid in the chamber through the outlet to the depositing system.

The present disclosure provides a control method of a compressor and a refrigerant circulation system. The control method includes deciding whether a current working volume state of the compressor is matched with a control instruction after the compressor completes a change to a working volume according to the control instruction, determining that the compressor operates normally in a case where the current working volume state of the compressor is matched with the control instruction, and determining that the compressor operates in fault in a case where the current working volume state of the compressor is not matched with the control instruction.

The present disclosure provides a control method of a compressor and a refrigerant circulation system. The control method includes deciding whether a current working volume state of the compressor is matched with a control instruction after the compressor completes a change to a working volume according to the control instruction; determining that the compressor operates normally in a case where the current working volume state of the compressor is matched with the control instruction; and determining that the compressor operates in fault in a case where the current working volume state of the compressor is not matched with the control instruction.

According to some embodiments, system and methods are provided, comprising providing a dual-mode model for a reciprocating compressor, wherein the model includes a measurement mode and a tuning mode; receiving one or more inputs to the model from an operating reciprocating compressor; and in response to receipt of the one or more inputs, executing the model in at least one of the measurement mode and the tuning mode, wherein: in a measurement mode, execution of the model further comprises calculating an actual flow rate of gas in the compressor based on the one or more inputs; and in a tuning mode, execution of the model further comprises calculating one of an unloader setting and a speed set point of a physical element of the compressor for a given flow rate of gas. Numerous other aspects are provided.

A hydraulic pressure intensifier (1) is described comprising a housing (2) having a low pressure chamber (3) and a high pressure chamber (4), force transmitting means (5) between the low pressure chamber (3) and the high pressure chamber (4), and a switching valve (8) connecting the low pressure chamber (3) to a first pressure or to a second pressure different from the first pressure. It is intended to have a large volume on the high pressure side of the pressure intensifier. To this end the switching valve (8) is controlled by a pilot valve 18.

A method for determining a flow volume of a fluid delivered by a pump, wherein the flow volume is determined as a function of predefined pump information depending on a pump geometry, rotation speed information, which correlates with the rotation speed of the pump, and pressure information, which correlates with a differential pressure at the pump.

A compressor system for a puncture repair kit, in which a supply pressure of compressed air is controlled to a specified pressure Pp or less without the use of a relief valve, having a motor, a piston, which is driven by the motor via a crank mechanism and has a cylinder component with a cylinder main body having a pump chamber, in which a piston is movable between a bottom dead center and a top dead center and air is compressed, and a receiving chamber for receiving the compressed air compressed in the pump chamber through an air discharge valve. The cylinder main body is elastically deformable as the pressure increases, the cylinder main body being deformable to such an extent that the compression volume V2 of the cylinder fulfills the following expression (a) 0.3?V1?P0/(PP?P0)=<V2<0.8?V1?P0/(PP?P0) (a), where V1 is a swept volume which is a cylinder volume while the piston moves from the bottom dead center to the top dead center, V2 is a compression volume which is a cylinder volume when the piston is located at the top dead center, and P0 is an air pressure.

A hydraulic pressure intensifier (1) is described comprising a housing (2) having a low pressure chamber (3) and a high pressure chamber (4), force transmitting means (5) between the low pressure chamber (3) and the high pressure chamber (4), and a switching valve (8) connecting the low pressure chamber (3) to a first pressure or to a second pressure different from the first pressure. It is intended to have a large volume on the high pressure side of the pressure intensifier. To this end the switching valve (8) is controlled by a pilot valve 18.

According to some embodiments, system and methods are provided, comprising providing a dual-mode model for a reciprocating compressor, wherein the model includes a measurement mode and a tuning mode; receiving one or more inputs to the model from an operating reciprocating compressor; and in response to receipt of the one or more inputs, executing the model in at least one of the measurement mode and the tuning mode, wherein: in a measurement mode, execution of the model further comprises calculating an actual flow rate of gas in the compressor based on the one or more inputs; and in a tuning mode, execution of the model further comprises calculating one of an unloader setting and a speed set point of a physical element of the compressor for a given flow rate of gas. Numerous other aspects are provided.