A compressor according to an embodiment includes: a discharge valve; a discharge space formed downstream of the discharge valve; a liquid injection hole for injecting a refrigerant liquid into the discharge space; and a heat medium flow path located opposite to the discharge space across a partition wall forming the discharge space.

A refrigeration system, in particular a transport refrigeration system, comprising: a refrigerant circuit, which in particular works using CO.sub.2 as the refrigerant and in which there is guided a total mass flow of the refrigerant; a high-pressure-side heat exchanger arranged in the refrigerant circuit and cooling refrigerant compressed to a high pressure; at least one cooling stage which expands the principal mass flow from the intermediate-pressure collector to a low pressure in at least one cooling expansion member and in so doing makes refrigeration capacity available at a low-pressure-side heat exchanger; and a refrigerant compressor unit which compresses the principal mass flow from a low pressure to a high pressure, wherein the refrigerant compressor unit has a first compressor stage for compressing, to a medium pressure, the refrigerant of the principal mass flow supplied at low pressure, and a second compressor stage for compressing, to a high pressure, the refrigerant of the principal mass flow that has been compressed to a medium pressure.

A device includes at least one volume that comprises a liquid quantity of a liquid and a partial volume with a working medium. The device further includes multiple volume limiting elements which limit the at least one volume and which are configured such that one or more passages allow outflow of a maximum of a predetermined partial quantity of the liquid quantity during one or more of a compression period, an expansion period, or a displacement period. The liquid quantity performs a rotation about an axis of rotation. The multiple volume limiting elements are configured to prevent an annular flow of the liquid quantity about the axis of rotation. The at least one volume is changeable in terms of its overall size by displacement of at least one of the volume limiting elements.

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.

A compressor assembly includes a compressor having a cylinder and a connecting rod in a connecting rod plane. The connecting rod includes a compressor piston and a connecting rod bearing. The compressor assembly includes a drive having an axis of rotation, a drive shaft, and a housing. The drive shaft is mounted in a drive shaft bearing and has a connecting rod side end and a connecting rod remote end. The drive shaft has a connecting-rod receiving portion which is arranged eccentrically to the axis of rotation of the drive at the connecting rod side end.

Systems and methods are described for a reciprocating mechanism. The system includes at least one axially translating y-axis component configured to reciprocate substantially along a y-axis with a reciprocating motion of a piston assembly relative to a base. The system also includes at least one x-axis component slidingly coupled via at least one bearing assembly to and translating with the at least one y-axis component along the y-axis. The at least one x-axis component is configured to reciprocate substantially perpendicularly to the y-axis relative to the at least one y-axis component, and includes an orbital output component and an orbital linking component disposed substantially concentric with the orbital output component. The system also includes a stationary output component rotatably attached to the base in a direction that is substantially perpendicular to both the x-axis and y-axis, and a stationary linking component rotatably attached to the base in a direction that is substantially concentric with the stationary output component.

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.

The present invention is directed to a dual engine-compressor system having a crankcase enclosing a crankshaft and having engine cylinder housings and compressor cylinder housings linearly disposed on opposite sides of the crankcase. Combustion pistons are reciprocatingly disposed in the engine cylinder housings and defines alternating combustion chambers on opposite sides of the pistons. Compressor pistons are reciprocatingly disposed in the compressor housings and define alternating low and high pressure compressor chambers on opposite sides of the compressor pistons. The compressor pistons undergo a 4-cycle process to drawn in, re-distribute, and then compress fluid. The compressor cylinder and piston has a series of one-way intakes and reed valves to selectively draw or push fluid in response to movement of the compressor piston.

A multi-cylinder reciprocating compressor, especially suitable for carbon dioxide frigorific circuits, wherein the high-pressure chambers of the heads are connected via an external manifold, comprising a high-pressure cock which, in co-operation with the casing, defines a channel which environmental air flows through to remove heat.

A refrigeration system, in particular a transport refrigeration system, comprising: a refrigerant circuit, which in particular works using CO.sub.2 as the refrigerant and in which there is guided a total mass flow of the refrigerant; a high-pressure-side heat exchanger arranged in the refrigerant circuit and cooling refrigerant compressed to a high pressure; at least one cooling stage which expands the principal mass flow from the intermediate-pressure collector to a low pressure in at least one cooling expansion member and in so doing makes refrigeration capacity available at a low-pressure-side heat exchanger; and a refrigerant compressor unit which compresses the principal mass flow from a low pressure to a high pressure, wherein the refrigerant compressor unit has a first compressor stage for compressing, to a medium pressure, the refrigerant of the principal mass flow supplied at low pressure, and a second compressor stage for compressing, to a high pressure, the refrigerant of the principal mass flow that has been compressed to a medium pressure.