A reciprocating piston machine includes a first cylinder and a first piston assigned to the first cylinder and a second piston assigned to the first cylinder or a second cylinder. The reciprocating piston machine further includes a crankshaft having an eccentric crankshaft journal and a drive shaft coupling configured for coupling a drive shaft of a drive motor for driving the crankshaft, a first connecting rod configured to deflect the first piston and configured to be moved by the eccentric crankshaft journal, and a second connecting rod configured to deflect the second piston and configured to be moved by a bearing pin. The reciprocating piston machine additionally includes at least one of a first elastomer element arranged between the bearing pin and the first connecting rod and a second elastomer element arranged between the bearing pin and the second connecting rod.

A heat exchanger generally employs a method for supplying liquid having critical pressure or higher or high pressure in order to suppress boiling. However, gas obtained by a evaporator behind the heat exchanger has relatively low pressure, and therefore supplying the liquid to the heat exchanger requires a system for converting an energy form of the obtained gas into kinetic energy or electrical energy, and increasing the pressure by a mechanical pump. Thus, the complicated system involving an efficiency loss is only solution, and it is difficult to achieve simplification of a system or reduction in the weight of a propellant supply device in a moving body, specifically, a flying object.

A heat exchanger generally employs a method for supplying liquid having critical pressure or higher or high pressure in order to suppress boiling. However, gas obtained by a evaporator behind the heat exchanger has relatively low pressure, and therefore supplying the liquid to the heat exchanger requires a system for converting an energy form of the obtained gas into kinetic energy or electrical energy, and increasing the pressure by a mechanical pump. Thus, the complicated system involving an efficiency loss is only solution, and it is difficult to achieve simplification of a system or reduction in the weight of a propellant supply device in a moving body, specifically, a flying object.

A connector (24) and method of connecting a compressor assembly (10) that increases the pressure of a fluid are described. The compressor assembly (10) includes cylinders (12a,b), crank shaft housings (18a,b), and a motor housing (22). The connector (24) is disposed between the cylinders (12a,b) and the crank shaft housing (18a,b) and configured to engage the cylinders (12a,b) such that vibration during operation of the compressor assembly is reduced through the placement of the connector (24) corresponding to a center of gravity of the compressor assembly (10). The connector may also be used by the compressor assembly as a heat sink, inlet, mount, filter, and/or to provide other functions that improve the operation of compressor assembly.

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 rolling cylinder displacement compressor including a minimum pressure bypass port as an opening of a minimum pressure bypass valve flow path, which is connected to a compression chamber formed in the compression portion in a lowest pressure state, of the bypass valve flow path is arranged such that a compression chamber faces an opening of the discharge flow path or the minimum pressure bypass port. The minimum pressure bypass port may be configured such that a minimum pressure port center as the center of the minimum pressure bypass port is arranged in a rotation advanced-side region with respect to an advanced radius line as a line connecting a cylinder advanced corner point of the compression chamber at the start of a compression stroke and the rotation center of the rolling cylinder.

A hydraulically driven intensifier for increasing pressure of gas comprising a piston-driven compression chamber for gas, operatively connected to an adjacent hydraulic chamber, with lubricant coupling in the compression chamber of the intensifier to circulate the lubricating fluid for cooling and lubricating the piston. A multistage compression system for gas, comprising the aforementioned intensifier, preferably several thereof operatively connected in series.

A fluid end assembly comprising a plurality of fluid end sections positioned in a side-by-side relationship. Each section comprises a housing containing a reciprocating plunger. One and only one packing seal is installed within the housing and surrounds and engages an outer surface of the plunger. A retainer compresses and holds the packing seal within the housing. The retainer is secured to the housing using a clamp, such that no threads are formed in the housing of the fluid end section and no threads are formed in the retainer.

A fluid end assembly comprising a plurality of fluid end sections positioned in a side-by-side relationship. Each section comprises a housing containing a reciprocating plunger. One and only one packing seal is installed within the housing and surrounds and engages an outer surface of the plunger. A retainer compresses and holds the packing seal within the housing. The retainer is secured to the housing using a clamp, such that no threads are formed in the housing of the fluid end section and no threads are formed in the retainer.

A fluid end assembly comprising a plurality of fluid end sections positioned in a side-by-side relationship. Each fluid end section comprises a housing having a bore formed therein for housing a reciprocating plunger. Fluid is prevented from leaking around the plunger by a packing seal assembly. The packing seal assembly comprises one and only one packing seal.