The present disclosure provides generally for a fluid-dispensing device. More specifically, the present disclosure provides for a precision fluid-dispensing device that may deliver a predefined volume of fluid quickly and reliably. In some aspects, the precision fluid-dispensing device may be used to deliver a fluid to a receiving container, such as in a manufacturing line, as a non-limiting example. In some embodiments, the precision fluid-dispensing device may dispense very accurate volumes of fluid using the head pressure of the fluid from an elevated reservoir or pressurized fluid supply. In some implementations, the precision fluid-dispensing device may dispense fluid gently and quickly, which may allow for handling of fluids that may be sensitive to agitation or mixing.

A liquid pump having a pump liner and a pump piston, wherein the pump liner defines a central longitudinal bore and a transverse inlet bore communicating with the central bore for conveying a liquid. The pump piston has a centerline intersecting with a centerline of the transverse inlet bore, and further has a flat surface formed parallel with the piston centerline at a distal end of the piston. The flat surface defines a cut-out portion of the piston, wherein the cut-out portion has a hydraulic diameter equal to the diameter of the transverse inlet bore of the liner, and a distance from the centerline of the piston to the flat surface defining the cut-out portion is greater than or equal to ½ of the diameter of the transverse inlet bore of the liner.

A liquid pump having a pump liner and a pump piston, wherein the pump liner defines a central longitudinal bore and a transverse inlet bore communicating with the central bore for conveying a liquid. The pump piston has a centerline intersecting with a centerline of the transverse inlet bore, and further has a flat surface formed parallel with the piston centerline at a distal end of the piston. The flat surface defines a cut-out portion of the piston, wherein the cut-out portion has a hydraulic diameter equal to the diameter of the transverse inlet bore of the liner, and a distance from the centerline of the piston to the flat surface defining the cut-out portion is greater than or equal to ½ of the diameter of the transverse inlet bore of the liner.

Plunger pump includes cylinder having inside cylinder chamber; plunger disposed in cylinder to be relatively movable forward and backward to cylinder chamber so outer plunger's circumferential face is in slide contact with cylinder's inner circumferential face, and having cut face on distal end's outer periphery; and suction and discharge ports provided to cylinder to communicate with cylinder chamber, plunger pump transferring fluid by reciprocating plunger in axial direction while rotating plunger relative to cylinder chamber to let suction and discharges ports alternately communicate with cylinder chamber, wherein cylinder includes cylinder main body and spacer section being disposed in cylinder main body's inner portion of proximal end side, and sliding against plunger's portion closer to proximal end side than portion of plunger advancing and retracting into cylinder chamber, and plunger pump further includes seal section provided on cylinder's proximal end side for sealing cylinder main body, plunger and spacer section.

Plunger pump includes cylinder having inside cylinder chamber; plunger disposed in cylinder to be relatively movable forward and backward to cylinder chamber so outer plunger's circumferential face is in slide contact with cylinder's inner circumferential face, and having cut face on distal end's outer periphery; and suction and discharge ports provided to cylinder to communicate with cylinder chamber, plunger pump transferring fluid by reciprocating plunger in axial direction while rotating plunger relative to cylinder chamber to let suction and discharges ports alternately communicate with cylinder chamber, wherein cylinder includes cylinder main body and spacer section being disposed in cylinder main body's inner portion of proximal end side, and sliding against plunger's portion closer to proximal end side than portion of plunger advancing and retracting into cylinder chamber, and plunger pump further includes seal section provided on cylinder's proximal end side for sealing cylinder main body, plunger and spacer section.

An angle adjustment mechanism for a pump and a motor includes a base, an eccentric bushing and a fixed link. The base has a motor flange for mounting a motor, a pump flange opposite the motor flange for mounting a pump, a hinge disposed between the motor flange and the pump flange and a pair of spaced apertures disposed opposite the hinge. The eccentric bushing has a body portion received in one of the apertures of the base and an inner bore with an axial center line offset from an axial center line of the body portion. The fixed link has a first pin portion received in the inner bore of the eccentric bushing and a second pin portion received in the other of the apertures of the base. With this arrangement, rotation of the eccentric bushing changes the distance between the apertures of the base, thereby changing an angle between the motor flange and the pump flange about the hinge.

An angle adjustment mechanism for a pump and a motor includes a base, an eccentric bushing and a fixed link. The base has a motor flange for mounting a motor, a pump flange opposite the motor flange for mounting a pump, a hinge disposed between the motor flange and the pump flange and a pair of spaced apertures disposed opposite the hinge. The eccentric bushing has a body portion received in one of the apertures of the base and an inner bore with an axial center line offset from an axial center line of the body portion. The fixed link has a first pin portion received in the inner bore of the eccentric bushing and a second pin portion received in the other of the apertures of the base. With this arrangement, rotation of the eccentric bushing changes the distance between the apertures of the base, thereby changing an angle between the motor flange and the pump flange about the hinge.

A micropump including: a stator (4); a rotor (6) slidably and rotatably mounted at least partially in the stator, the rotor comprising a first axial extension (24) having a first diameter (D1) and a second axial extension (26) having a second diameter (D2) greater than the first diameter; a first valve (V1) formed by a first valve seal (18) mounted on the stator around the first axial extension, in conjunction with a first channel (42) in the rotor that is configured to allow liquid communication across the first valve seal when the first valve is in an open position; a second valve (V2) formed by a second valve seal (20) mounted on the stator around the second axial extension, in conjunction with a second channel (44) in the rotor that is configured to allow liquid communication across the second valve seal when the second valve is in an open position; a pump chamber (8) formed between the rotor and stator and between the first valve seal and second valve seal, and a cam system comprising a cam track (22, 22′) on one of the rotor or stator and a cam follower (36, 36′) on the other of the rotor or stator for axially displacing the rotor relative to the stator as a function of the rotation of the rotor, the cam track comprising a valves-closed chamber-full section (28), a valves-closed chamber-empty section (30), an intake section (32) and an expel section (34). The expel section comprises an expel hold position (34b) defining an intermediate axial position between the valves-closed chamber-full section and valves-closed chamber-empty section for partial delivery of a pump cycle volume during the expel phase.

A micropump including: a stator (4); a rotor (6) slidably and rotatably mounted at least partially in the stator, the rotor comprising a first axial extension (24) having a first diameter (D1) and a second axial extension (26) having a second diameter (D2) greater than the first diameter; a first valve (V1) formed by a first valve seal (18) mounted on the stator around the first axial extension, in conjunction with a first channel (42) in the rotor that is configured to allow liquid communication across the first valve seal when the first valve is in an open position; a second valve (V2) formed by a second valve seal (20) mounted on the stator around the second axial extension, in conjunction with a second channel (44) in the rotor that is configured to allow liquid communication across the second valve seal when the second valve is in an open position; a pump chamber (8) formed between the rotor and stator and between the first valve seal and second valve seal, and a cam system comprising a cam track (22, 22′) on one of the rotor or stator and a cam follower (36, 36′) on the other of the rotor or stator for axially displacing the rotor relative to the stator as a function of the rotation of the rotor, the cam track comprising a valves-closed chamber-full section (28), a valves-closed chamber-empty section (30), an intake section (32) and an expel section (34). The expel section comprises an expel hold position (34b) defining an intermediate axial position between the valves-closed chamber-full section and valves-closed chamber-empty section for partial delivery of a pump cycle volume during the expel phase.

A pump includes: a stator (4), a rotor (6) slidably and rotatably mounted at least partially in the stator, the rotor comprising a first axial extension (24) having a first diameter (D1) and a second axial extension (26) having a second diameter (D2) greater than the first diameter, a first valve (V1) formed by a first valve seal (18) mounted on the stator around the first axial extension, in conjunction with a first channel (42) in the rotor that is configured to allow liquid communication across the first valve seal when the first valve is in an open position, a second valve (V2) formed by a second valve seal (20) mounted on the stator around the second axial extension, in conjunction with a second channel (44) in the rotor that is configured to allow liquid communication across the second valve seal when the second valve is in an open position; a pump chamber (8) formed between the rotor (6) and stator (4) and between the first valve seal (18) and second valve seal (20); and a pump chamber seal (22) circumscribing the rotor second axial extension and separating the pump chamber (8) from an external environment. The stator (4) further comprises a dead-zone seal section (40) surrounding a dead-zone volume (39) formed between the rotor second axial extension (26) and the stator (4), wherein the dead-zone seal section (40) comprises axially extending portions (58) connected to upper and lower radial portions (60,60′) to form a closed sealing circuit.