Abstract: Disclosed is a hybrid type air-compressor, which has a main body including a cylinder having upper and lower portions, a motor assembly including an eccentric shaft passing through a side surface of the main body to eccentrically rotate in the cylinder, a first communication part covering an upper portion of the cylinder of the main body and introducing air to discharge the air to the upper portion of the cylinder, a second communication part covering a lower portion of the cylinder of the main body and introducing air to discharge the air to the lower portion of the cylinder; and an air compressing means connected to the eccentric shaft of the motor assembly and vertically moving in the cylinder to alternately compress air introduced into the upper and lower portions of the cylinder.

Abstract: The invention relates to a piston engine comprising one or more air/gas-compressing cylinder-piston units, a crank mechanism connected to the piston in the said cylinder or cylinders for movement of the piston in the cylinder, which crank mechanism is drivingly connected to a rotor in an electric motor. The invention also relates to a coupling and a simple connection for a counterweight.

Abstract: A pressure generating device generates a hydraulic pressure as a result of a tensile or compressive load. The device has connections, one of which can be rigidly connected to a frame by way of a mechanism for introducing a mechanical tensile or compressive load, a pressure cylinder and a piston unit extending at least partially and flexibly in the pressure cylinder and bounding a hydraulic chamber filled with hydraulic fluid jointly with the pressure cylinder. The chamber has a simple and inexpensive construction. The connections are connected to the pressure cylinder or the piston unit by way of a coupling device that is configured such that the same hydraulic chamber has pressure applied thereto under tensile load and under compressive load.

Abstract: In at least some embodiments, a pump includes a turning member and a reciprocating member coupled to the turning member, the reciprocating member performing a pumping motion as the turning member turns. The pump also includes at least one stabilization component in contact with the reciprocating member to stabilize the pumping motion.

Abstract: A reciprocating compressor is provided with a reciprocating compressor frame which includes a central body and at least two crosshead guides extending from opposite sides of the central body. Additionally, the compressor frame has angled crosshead guide support structures extending outwardly from the central body along a respective crosshead guide.

Abstract: The present invention concerns a drive mechanism for oscillating positive-displacement machines such as for example diaphragm pumps comprising an eccentric shaft and a plurality m of piston rods, wherein the piston rods are connected to the eccentric shaft in such a way that rotation of the eccentric shaft produces an oscillating linear movement of the piston rods. To provide a corresponding drive mechanism which avoids or at least reduces the described disadvantages it is proposed according to the invention that the eccentric shaft and the piston rod are connected together by way of a sliding unit guide.

Abstract: Reciprocating motion can be converted to rotary motion through a crankshaft and a connecting rod. In a joint between a connecting rod and a piston, the connecting rod rocks with respect to the piston. In some situations, the connecting rod is a pullrod always in tension or a pushrod always in compression making it difficult to lubricate the bearing surfaces. A joint is disclosed in which the bearing surfaces rock with respect to each other with no sliding between the surfaces. The connecting rod has a bearing surface that is part of a cylinder having a radius equal to a distance between a central axis of the journal to which the connecting rod is coupled and the bearing surface. The pin has a convexly- or concavely-curved bearing surface and the local radius is based on material properties and the local peak force that the rocking joint is designed to transmit.

Abstract: A displacement assembly includes a rotor and a plurality of reciprocating members in engagement with the rotor. The displacement assembly further includes a ring assembly. The ring assembly defines a cam surface that is in engagement with the reciprocating members. The ring assembly has a first ring and an axially adjacent second ring with at least one of the first and second rings being adapted for selective movement relative to the other between a neutral position and a displaced position. The first ring has a first ring portion defining a bore that has an inner surface. The second ring has a second ring portion defining a bore that has an inner surface. A first circumferential portion of the inner surface of the first ring portion and a second circumferential portion of the inner surface of the second ring portion define the cam surface in the displaced position.

Abstract: A reciprocating compressor comprises: a cylinder having an oil pocket on an inner circumferential surface of a piston insertion hole for inserting a piston with a predetermined width and depth; and a piston having a bearing portion protruding so as to slidably contact an inner circumferential surface of the piston insertion hole, and inserted into the piston insertion hole of the cylinder, wherein the bearing portion is formed to have a length shorter than that of the oil pocket of the cylinder. Accordingly, a frictional loss between the cylinder and the piston is reduced.

Abstract: A cryogenic piston expander may reduce or eliminate the inertia of system, as compared to conventional cryogenic piston expanders that utilize a heavy flywheel. The cryogenic piston expander of the present invention may use a single bent running from a motor to a large sprocket mounted on a main shaft of the cryogenic piston expander.

Abstract: In various embodiments, energy-storage systems are based upon an open-air arrangement in which pressurized gas is expanded in small batches from a high pressure of, e.g., several hundred atmospheres to atmospheric pressure. The systems may be sized and operated at a rate that allows for near isothermal expansion and compression of the gas.

Abstract: A primary scotch yoke and a secondary scotch yoke are coupled in opposing arrangement and rigidly attached to a linearly reciprocating element. Each scotch yoke includes a rotary actuator with a cam follower and a yoke attached to the reciprocating element. Each yoke has a cam with an open gap through which the follower may be disengaged from the cam and stopped to an idle position. The follower of the secondary scotch yoke is kept idle in a position similarly disengaged from its cam. A controller detects a failure in the primary scotch yoke, disengages the cam follower of the primary yoke from its cam, and energizes the secondary scotch yoke, thereby causing its cam follower to engage its yoke and continue to provide uninterrupted motion to the reciprocating element, in particular the portable pneumatic pump driving an artificial heart.

Abstract: Disclosed are a reciprocating compressor and a refrigerating apparatus having the same, wherein a magnet bearing is inserted between facing surfaces between a cylinder block and a crank shaft and the magnet bearing so as to generate a magnetic force both in a shaft direction and in a radial direction, so that the cylinder block and the crank shaft can be supported both in the shaft direction and in the radial direction, thereby reducing a frictional loss due to an eccentric load of the crank shaft, and also, both magnets are disposed to overlap each other so as to prevent an increase in an input load due to the magnetic force between the magnets, resulting in further improvement of energy efficiency of the compressor.

Abstract: A mud pump is provided that includes a pump shaft having substantially circular eccentric lobes. Each lobe is rotatably mounted in a connecting rod that, in turn, moves a slide in a horizontal and linearly manner. A piston rod is operatively couples a pump module to one or both sides of each slide frame and a pump module. As the pump shaft turns, each lobe causes the slide to move side to side. As the slide moves side to side, each piston rod operates a pump module whose outputs can be coupled to a common manifold.

Abstract: A reciprocating device, comprising: a motor; at least one crank mechanism attached to the motor; at least one rod attached to the crank mechanism; and at least one sleeve surrounding at least a portion of the at least one rod, adapted to dampen optional vibrations of the rod.

Abstract: The invention relates to mechanical engineering, in particular to piston machines and mechanisms for converting the movement of the pistons thereof into shaft rotation. The technical result of the invention involves increasing the operational reliability, extending the service life, improving the specific mass and dimensional characteristics and enhancing the effectiveness of a machine. The essence of the invention is that the piston and the crank of a piston machine are interconnected by means of a hinged joint with at least a flat hinge which enables the piston to self-center along the surface of a cylinder owing to the movement of the piston with respect to the crank in any direction on a plane that intersects the longitudinal axis of the cylinder. The surfaces of the crank that take up reactive torque are constricted by rollers with synchronized toothed wheels.

Abstract: The invention relates to mechanical engineering, in particular to piston machines. The technical result of the invention consists in increasing the reliability and service life of the cylinder-piston group of a piston machine and the power-to-displacement ratio thereof (when the machine is used as an engine) by decreasing the mass of the reciprocatingly moving elements of the machine, and in improving the efficiency by substituting boundary sliding friction in a badly oiled cylinder-piston pair by rolling friction so that the rolling elements are prevented from slipping. The essence of the invention is that the crosshead and the body of the machine are provided with guides with contact surfaces and that rollers are arranged between the contact surfaces in order to transmit reactive energy from the crosshead to the body.

Abstract: A shifting device (1) for shifting a motor vehicle transmission with a shift selector shaft on which a plurality of shift elements (2) such as shift forks or shift rockers (3) are arranged and can be displaced to carry out a shifting operation. The shifting device (1) includes one hydraulic shift cylinder (5, 11, 18, 25), that can be actuated from both sides, with a piston (9, 15, 16, 19, 26) that can be displaced within a cylinder housing (6) and which is actively connected with a shift element (2) to be actuated. To simplify a shifting device (1) of this type, the piston (9, 15, 16, 19, 26) has a piston rod (10, 17, 23, 29) that follows the movement of the piston (9, 15, 16, 19, 26) and can be connected directly to the shift element (2) in a detachable manner.

Abstract: A scotch yoke engine or pump with a female Vee land means (2a) extending parallel to the cylinder axis (1) of cylinder (11) and including two surfaces, the first planar surface extending parallel to a first plane, and the second planar surface extending parallel to a second plane, the first plane and the second plane being at an angle to each other, a third guide means (4a) including two surfaces extending parallel to the cylinder axis, the first surface extending parallel to the first plane and the second surface extending parallel to the second plane; a fastener means (6a) such as a bolt or stud adapted to fasten the third guide means into a corner (20a) of the Vee land, the Vee land located in the axial foot print of the cylinder.

Abstract: The actuator unit includes a hollow body defining a sliding chamber within; a piston mounted sliding inside said sliding chamber such to provide an actuation force and operated by a fluid fed from the outside; a body having one transmission end for the transmission of said actuation force prolonged outside said sliding chamber and one hooking end hooked to said piston, amplification means being interposed between said body and said piston to amplify said actuation force so as to obtain an amplified actuation force.

Abstract: The invention relates to a method of calibrating a connecting rod arrangement comprising a crankshaft eye and a connecting rod eye. In order to achieve the best possible parallelism between the connecting rod eye and the crankshaft eye a controlled energy input occurs in at least one predefined surface area of the connecting rod, so that outside a neutral axis a local structural change and thus a tension in the connecting rod occurs.

Abstract: A lever with a shifting pivot or fulcrum point such that in pivoting of the lever between a first position and a second position for at least one angular segment of such pivoting about a first fulcrum point and for a second angular sector of such pivoting, pivots about a second fulcrum point.

Abstract: An improved scotch yoke engine of pump including a piston joined to a yoke structure wherein the piston (1) is free to move along at least one axis defined by a flying cross (60) relative to the yoke structure (7) during piston reciprocation, the piston and yoke structure being joined in a flat type joint arrangement and the piston prevented from rotation around the piston axis by engagement of the piston and the yoke with the flying cross, the flying cross being not locked in position between the piston base (50) and the yoke shank end arrangement (700).

Abstract: An air pump comprises a cylinder, a piston, a piston rod, and four substantially rigid members. The piston is reciprocably movable within the cylinder and is secured to the piston rod. The first member is pivotably connected at its first end to the cylinder. The second member is pivotably connected at its first end to the piston rod and at its second end to the second end of the first member. The third member is pivotably connected at its first end to the connected second ends of the first and second members. The fourth member is pivotably connected to the cylinder and to the second end of the third member. The third member is arranged to transmit between the handle and the connected second ends of the first and second members a force resulting from a force applied to the handle.

Abstract: In an embodiment of the present invention, a piston apparatus of an automatic transmission includes a piston member capable of moving in the axial direction of the rotation shaft, and a hydraulic chamber, and has been configured so that the piston member moves in the axial direction due to pressure in the hydraulic chamber. The piston member includes a cylinder part that extends in the axial direction and to which pressure in the hydraulic chamber is transmitted, a pressing part that extends in the radial direction and presses against a friction engaging element of the automatic transmission, and a connecting part that connects the cylinder part and the pressing part and, with respect to the axial direction, is offset from the pressing part in a direction of separation from the friction engaging element. Also, the axial direction offset amount of the connecting part from the pressing part of the piston member has been set larger than the stroke amount of the piston member.

Abstract: An actuator rod (17) for a turbocharger pressure control assembly comprises a first elongate portion (17a) defining a first rod end and a second portion (17b) defining a second rod end. The first and second portions are pivotally joined to one another to allow a degree of relative pivotal motion therebetween in at least one plane perpendicular to the axis of said elongate first portion (17a).

Abstract: A high pressure fuel pump for an internal combustion engine having a cylinder, a plunger slidably fitted in the cylinder and a seal mechanism for blocking fuel leakage from an end of a sliding portion between the cylinder and the plunger and also for preventing an lubricant for a driving mechanism of the plunger from entering into the cylinder from the end of the sliding portion of the cylinder and the plunger. A holder surrounding the end of the sliding portion of the cylinder and the plunger is provided. The seal mechanism comprises two mutually independent seal devices mounted with a specific spacing in a longitudinal direction from the end of the sliding portion of the cylinder and the plunger along a circumference of the plunger. The two seal devices are held on the circumference of the plunger by the holder surrounding the end of the sliding portion of the cylinder and the plunger while keeping the specific spacing.

Abstract: The invention pertains to a cartridge (1) with at least one chamber (6a, 6b) for accommodating a substance that respectively features a dispensing opening (11a, 11b) and another opening that is closed by a piston (8a, 8b) that can be displaced in the chamber and serves for dispensing the substance. The cartridge (1) furthermore features a piston rod mechanism (4) for displacing the piston (8a, 8b) in the chamber (6a, 6b). In this case, the piston rod mechanism is composed of several piston rods (14, 14a, 14b, 15, 15?) that can be transferred from a first dispensing stage to a second dispensing stage with the aid of a spring element (18, 18a, 18b).

Abstract: An air pump comprises a cylinder, a piston, a piston rod, three substantially rigid members, and a handle. The piston is reciprocably movable within the cylinder and is secured to the piston rod. The first member is pivotably connected at its first end to the cylinder. The second member is pivotably connected at its first end to the piston rod and at its second end to the second end of the first member. The third member is pivotably connected at its first end to the connected second ends of the first and second members. The handle is pivotably connected to the second end of the third member. The third member is arranged to transmit between the handle and the connected second ends of the first and second members a force resulting from a force applied to the handle.

Abstract: A heart pump has a pump chamber and a pump element that strokes between a retracted and an extended position. A motor rotates a drive shaft in a single direction. A reversing mechanism coupled between the drive shaft of the motor and the pump element converts rotary motion of the drive shaft to reciprocal stroking movement of the pump element. A mechanical stroke length controller connected to the reversing mechanism varies the stroke length in response to changes in fluid pressure in the pump chamber.

Abstract: This disclosure concerns machines that convert rotating motion to reciprocation, and vice-versa, and more particularly, but not exclusively, to reciprocating piston machines. Some embodiments include a crankshaft defining a crankshaft-drive and at least one radially extending piston-journal spaced from the crankshaft-drive, and a piston configured to pivotally engage the piston-journal. The piston defines a cylindrical head and an elongate body. Some embodiments further include a drive-member defining a central-axis-of-rotation and being rotatably engageable with the crankshaft-drive. Some embodiments also include a block defining one or more cylinders for receiving one or more pistons. The drive-member rotates when the piston reciprocates, and vice-versa.

Abstract: A crosshead and connecting rod assembly for a pump comprises a connecting rod which includes a first end that is rotatably connected to the crankshaft of the pump, a second end that comprises a generally cylindrical configuration, and a shaft that extends between the first and second ends. The second end comprises at least one annular shoulder adjacent to the shaft, and the crosshead and connecting rod assembly further comprises a crosshead which includes a body that comprises a generally semi-cylindrical socket within which the second end is rotatably received and at least one trunnion that comprises a generally semi-cylindrical recess which aligns with the socket and within which the shoulder is rotatably received when the trunnion is connected to the body.

Abstract: A vacuum pump comprises a casing having a bottom forming an aperture therein and a chamber slidably coupled within the casing. The chamber has a bottom forming an aperture therein. The vacuum pump further comprises a piston slidably coupled within the chamber. The piston includes an upper portion generally parallel to the chamber bottom. The piston further includes a hollow shaft extending from a bottom surface of the upper portion. The shaft has a first end adjacent to the upper portion and a second opposing end. The shaft is configured to fit within the chamber aperture and the casing aperture. The shaft includes at least one aperture positioned at the first end. The second end of the shaft is coupled to the casing at the casing aperture. The vacuum pump is configured to evacuate air from a flexible storage container by pushing the chamber in a downward direction.

Abstract: A two-stroke engine (1) including, an engine block (2) having a cylinder (3), a double-ended piston (4) received for reciprocation in the cylinder (3), the piston (4) comprising a body having first and second opposing ends (7, 9), the first end (7) forming a wall of the combustion chamber (8), the second end (9) forming a wall of a pre-compression chamber (10), the piston (4) including a piston opening (11) between the first and second ends (7, 9); at least one passage extending from the pre-compression chamber (10) to the combustion chamber (8) for charging the combustion chamber(8); a connecting rod (6) operatively connecting the piston (4) to a crankshaft (5), and characterised in that the piston opening (11 ) encloses the connecting rod (6) and the crankshaft (5) protrudes through the piston opening (11).

Abstract: A fluid pump comprising a plurality of piston cylinders (1, 2, 3, 4), wherein each individual cylinder has a piston rod (5, 6, 7, 8) with a piston (9, 10, 11, 12) arranged in the cylinder and a valve housing (13, 14, 15, 16) mounted at the end of the cylinder opposite the piston rod, and a drive arrangement for the piston rods, said drive arrangement comprising two main gearwheels (17, 18) which mesh and rotate in opposite directions. The present fluid pump is characterized in that the reciprocating motion of the piston rods (5, 6, 7, 8), which extend in pairs in opposite directions, is effected with the aid of two beams (19, 20) that are fixed to the end of the respective pair of piston rods opposite the pistons (9, 10, 11, 12), and which extend at right angles relative to the piston rods, and that the beams are connected to the main gearwheels (17 18) by shaft pins (21, 22, 22, 23) which move in pairs in guides (24) provided in the longitudinal direction of the respective beam.

Abstract: A connection between a rod and crosshead in a reciprocating compressor includes threaded units, an anti-rotational securing device and axial positioning elements, wherein the threaded units has a first inner lock nut, provided with an inner thread onto which there is screwed a threaded end portion of the rod and provided with two outer threads with a different diameter, one of which is for connection to the left-handed anti-rotational securing device, and the units also include a second outer lock nut in the inner diameter of which a thread is provided.

Abstract: A highly reliable reciprocating compressor works efficiently with less energy, and produces smaller vibrations. This reciprocating compressor includes a crankshaft, a block, a piston, a connecting rod, and a balancing weight. The cylinder is placed offset such that an axis line thereof and an axis line of the main shaft do not cross each other. The center of gravity of the balancing weight is placed substantially opposite to the center of the eccentric section with respect to the axis line of the main shaft and deviated along a rotating direction of the main shaft from the place just opposite to the center of the eccentric section. The foregoing construction allows reducing lateral pressure of the piston, thereby increasing the reliability and efficiency of the reciprocating compressor, and allows to cancel unbalancing force produced by motions of the piston, the connecting rod and the eccentric section with motion of the balancing weight.

Abstract: A crosshead assembly in conjunction with a Stirling engine is disclosed. The assembly comprises a displacer piston (1), displacer rod (8), power piston (2), power piston crosshead assembly (2), displacer piston crosshead assembly (7), displacer crosshead connecting rod (6) and power crosshead connecting rod (5). In order to achieve a compact design, the displacer crosshead (7) and the power crosshead (2) are placed concentrically in such a way that the displacer crosshead oscillates within or partly within the power crosshead.

Abstract: Disclosed are crankshaft, single-plate cam and beam mechanisms that provide significant improvements in performance for 2 & 4-stroke engines, compressors and pumps. These cost effective mechanisms include linkages with the new and improved use of pivoting arms that operate with a variety of cylinder arrangements. One embodiment of the crankshaft mechanism has its crankpin roller positioned within a novel yoke-arm. The cam mechanism uses a pair of centrally positioned parallel links that are connected to roller cam followers and single or diametrically-opposed pistons. A pair of laterally extending follower arms connects to the ends of the links to provide support and alignment for the piston rods. Between the reciprocating links, cam followers and follower arms is a rotating odd-lobe plate cam. A beam mechanism uses opposite-direction extending balancing beams that are connected to links, cam followers and piston rods.

Abstract: A fluid pressure driven generator which includes a generator housing and a rotor positioned within the generator housing. A power shaft is positioned in the rotor with a moment arm connected between the power shaft and rotor. A high fluid pressure inlet will be formed in the housing and connected to a source of high pressure fluid. The housing will also have low pressure outlet which will feed a source of low pressure fluid.

Abstract: An air pump comprises a cylinder, a piston, a piston rod, three substantially rigid members, and a handle. The piston is reciprocably movable within the cylinder and is secured to the piston rod. The first member is pivotably connected at its first end to the cylinder. The second member is pivotably connected at its first end to the piston rod and at its second end to the second end of the first member. The third member is pivotably connected at its first end to the connected second ends of the first and second members. The handle is pivotably connected to the second end of the third member. The third member is arranged to transmit between the handle and the connected second ends of the first and second members a force resulting from a force applied to the handle.

Abstract: A yoke structure for a compressor is disclosed, which is applied to a scotch yoke type reciprocating compressor. The yoke structure comprises a crankshaft (10); a crankpin (20) connected to the crankshaft (10), to rotate along a predetermined round trajectory which has the crankshaft at its pivot, as the crankshaft rotates; a frame having a pair of slide ways (41) formed on two parallel inner faces of the frame (40) opposing each other, one or more pistons (30) to be fixed to outer faces of the frame outside the slide (41) ways; a sliding block (30) positioned between the pair of slide ways (41) and rotatably connected to the crankpin (20); and a pair of self-lubricating materials (32) attached to the sliding block (30) so as to be in contact with opposing faces of the slide ways (41).

Abstract: A pump (1) with an oscillating part having a housing (2) with a working chamber (3) and a crankcase (4) defined from the working chamber by the pump part. A pump drive mechanism (6) with a drive shaft (7) is located inside the crankcase (4) and the drive shaft is mounted on bearings (8, 9) that are arranged in the walls of the crankcase. The pump has a suction inlet separate from the crankcase. The pump (1) includes at least one flow channel in the crankcase wall for compensating pressure in the crankcase when the pump part oscillates and a flow damper arranged in the at least one flow channel. In a preferred embodiment, the at least one passage hole having at least one bearing therein is configured as the flow channel.

Abstract: The invention concerns a piston compressor with a piston, which is connected with a crank pin of a drive shaft via a connecting rod having a longitudinal channel. It is endeavored to make the manufacturing of a piston compressor cost effective. For this purpose, it is ensured that the shaft of the connecting rod is made as a sheet metal pipe.

Abstract: A hermetic compressor capable of appropriately injecting oil from an eccentric unit of a rotating shaft in accordance with amounts required by respective regions. The hermetic compressor comprises a compression chamber in which a refrigerant is compressed, a piston to compress the refrigerant in the compression chamber, a rotating shaft to provide a drive force to advance or retreat the piston in the compression chamber, the rotating shaft having an oil path formed therein, a hollow eccentric unit to eccentrically rotate as the rotating shaft rotates, a bushing coupled to the eccentric unit and having a closed surface to close an opening of the eccentric unit, and an oil injection port formed at the bushing to determine an injection direction and injection degree of oil injected along an inner peripheral surface of the eccentric unit.

Abstract: A scotch yoke type fluid device where the or each piston (32) has its own slider (18) and its own pair of sliding surfaces (30) disposed on the same side of the big end bearing (16) of the crank (12). The main crank axis (14) is movable along a path such that the pistons are neither substantially retarded nor advanced. The effective centre of mass of the crank, piston and slider remains stationary relative to the crank axis. Guide means (2030) constrain each piston to move along its piston axis. The guide means is transverse of the sliding surfaces (30) and engages crankcase mounted guides. An intermediate member may interconnect the piston and the slides capable of adjusting the intermediate member to change the compression ratio. For a device having opposed pistons, the yoke (6060) attached to the two pistons is split into two parts (6062a, 6062b) releasably held together.

Abstract: An actuator for an active suspension system includes an armature and a housing enclosing an interior. The interior has a volume that varies in response to movement of the armature. A wall of the housing forms a first aperture through which air passes in response to movement of the armature.

Abstract: A piston mechanism comprises a crankcase, a crankshaft with three crankpins, a cylinder with diverging pistons defining working chambers having inlet and outlet openings, and two connecting members, one of which cooperates with the middle crankpin and the other with the two outer crankpins. In the body of the cylinder there are guide channels provided, in which connecting rods are arranged in alternating sequence, which are attached to one or the other connecting member by their bases, forming two synchronous groups of connecting rods. The guide channels are provided with through-cuts in the working surface of the cylinder with outlets into its cavity so that the faces of the connecting rods of the synchronous groups facing the cavity of the cylinder form movable parts of its working surface.

Abstract: Dual capacity compressor including a power generating part (20) having a reversible motor (21, 22) and a crank shaft (23) inserted in the motor (21, 23), a compression part (30) having a cylinder (32), a piston (31), and a connecting rod (33), a crank pin (110) in an upper part of the crank shaft (23) eccentric to an axis of the crank shaft, an eccentric sleeve (120) rotatably fitted to the crank pin (110), and the connecting rod (33) respectively, a key member (130) for positive fastening of the eccentric sleeve (120) to the crank pin (110) in all rotation directions of the motor, and an eccentric mass (200) provided to the eccentric sleeve (120) for rotating the eccentric sleeve (120) around the crank pin (110), thereby preventing relative motion between components that sustain the eccentricity, and permitting a smooth motion between the components.

Abstract: An airless spray pump is provided with a single-acting piston pump which allows the use of a low-cost yoke drive. Motor and pump shaft are offset for most efficient force utilization.