A foam pump has dual, coaxial air and liquid cylinders, each having a respective air and liquid piston which move together during a dispensing operation. One or more air passageways between the air cylinder and a liquid-air mixing chamber are configured to impart rotation to an airstream passing from the air cylinder to the mixing chamber to increase turbulent mixing of the air and liquid in the mixing chamber. The liquid cylinder is axially aligned with the air cylinder to provide a low profile pump which does not require a dip tube or sleeve to communicate with the bottom of the liquid source when used in an inverted application wherein the foam pump is positioned below the source of liquid. A resilient valve member in the liquid outlet is biased to close on its own to prevent leaking in the event the air and liquid pistons do not fully return to the home position.

A fluid machine for a pneumatic or hydraulic drive system, said fluid machine being able to work as a fluid motor or as a fluid pump, comprising: at least two piston assemblies each comprising a piston means (110a-c), the at least two piston assemblies being operable to cause sequential reciprocating movement of the pistons means (110a-c); a drive member (120) rotatable about an axis and providing an annular, wave-like surface (122) extending at least partially radially to the axis, towards which the piston means (110a-c) project, wherein, in case of working as a fluid motor, the pistons means (110a-c) are arranged to drive rotation of the drive member (120) about the axis at least by a pushing action on said wave-like surface (122) or, in the case of working as a fluid pump, the piston means (110a-c) are arranged to cooperate with said wave-like surface (122) so that rotation of the drive member (120) drives sequential reciprocating motion of the piston means (110a-c).

The invention relates to a pump comprising a piston (1) which slides in a body (3) having a chamber (5) defined between an inlet valve (11) and an outlet valve (12), comprising an outlet valve element sliding during actuation in a sealed manner in the chamber (5), which comprises passage means (40) such that, at the end of the actuation, said outlet valve element (39) cooperates in a non-sealing manner with said passage means (40) in order to open said outlet valve (12), said inlet valve (11) comprising an inlet valve element (10) which slides after closure of the inlet valve (11) in a sleeve (9) of the body (3) having a reduced diameter and containing a spring (20) bearing on said inlet valve element (10) and on a bottom of said sleeve (9), said spring (20) returning the piston (1) into its rest position, said sleeve (9) having an inner diameter of less than 4.2 mm, said spring (20) having a force of at least 20 N, so that said pump delivers said fluid product at a pressure (P) of at least 15 bars.

A discharge pump (2) includes a stationary suction part (A) which includes a cylinder (A1) having a first check valve (V1) at a lower part thereof, and a mounting member (A3) to be mounted on a neck part of a container body, and an actuating member (B) which includes a discharge head (B4), a stem (B2), a piston guide (B1), and an annular piston (B3), a second check valve (V2) being formed between a lower end part of the annular piston and a lower part of the piston guide, and in a fitting part between the stem and the piston guide, an engaging unit (E) which is configured to restrict the stem and the piston guide from idling each other when screwing of the actuating member to the stationary suction part is released and the actuating member is raised from the stationary suction part is provided.

A discharge pump (2) includes a stationary suction part (A) which includes a cylinder (A1) having a first check valve (V1) at a lower part thereof, and a mounting member (A3) to be mounted on a neck part of a container body, and an actuating member (B) which includes a discharge head (B4), a stem (B2), a piston guide (B1), and an annular piston (B3), a second check valve (V2) being formed between a lower end part of the annular piston and a lower part of the piston guide, and in a fitting part between the stem and the piston guide, an engaging unit (E) which is configured to restrict the stem and the piston guide from idling each other when screwing of the actuating member to the stationary suction part is released and the actuating member is raised from the stationary suction part is provided.

An example apparatus to prevent side load in hydraulic override pumps includes a lever rotatably mounted to a support. The apparatus includes a pump cylinder rotatable about a first end of the pump cylinder. The apparatus also includes a pump rod operatively coupled to the lever to move within the pump cylinder based on rotation of the lever. The pump cylinder rotates when the pump rod moves within the pump cylinder.

An example apparatus to prevent side load in hydraulic override pumps includes a lever rotatably mounted to a support. The apparatus includes a pump cylinder rotatable about a first end of the pump cylinder. The apparatus also includes a pump rod operatively coupled to the lever to move within the pump cylinder based on rotation of the lever. The pump cylinder rotates when the pump rod moves within the pump cylinder.

A pipetting device includes a housing, a valve assembly, and an actuator assembly. The housing includes a tip for receiving a capillary tube. The valve assembly includes a shuttle valve having a filling position and a dispensing position and a valve rod. The actuator assembly includes an actuator, a valve trigger, a piston mount, and an indexing mechanism. The actuator extends from the housing and has a push button coupled to a push rod. The valve trigger being configured to engage the valve assembly and includes an aperture configured to receive the piston mount therein. The indexing mechanism is configured to index a rotated position of the push button to a predefined volume of dispensed fluid.

A pipetting device includes a housing, a valve assembly, and an actuator assembly. The housing includes a tip for receiving a capillary tube. The valve assembly includes a shuttle valve having a filling position and a dispensing position and a valve rod. The actuator assembly includes an actuator, a valve trigger, a piston mount, and an indexing mechanism. The actuator extends from the housing and has a push button coupled to a push rod. The valve trigger being configured to engage the valve assembly and includes an aperture configured to receive the piston mount therein. The indexing mechanism is configured to index a rotated position of the push button to a predefined volume of dispensed fluid.

[Object] To provide a trigger-type pump dispenser that makes it possible to prevent an out-of-nozzle squirting phenomenon that occurs at a final stage of sucking up of liquid out of a vessel into a cylinder. [Solution] A trigger-type pump dispenser A includes a handle structure 1, a nozzle base structure 2 attached to the handle structure 1, a trigger 3, a cylinder structure 4, a cap 5 by which the cylinder structure 4 is held down and attached to the mouth of a vessel, a piston structure 6 that slides inside the cylinder structure 4, an inverted-mortar-shaped lip 61 formed in the piston structure 6, a spring 7 that springs the piston structure 6, a valve case 8 attached to the nozzle base structure 2, a mortar-shaped valve seat 81 formed in the valve case 8, a leak valve 9, attached to a bottom part of the cylinder structure 4, that has a bulging portion 91 at a tip thereof, a first valve FV, and a second valve SV. A movement of the piston structure 6 from top dead center to bottom dead center causes liquid in the cylinder structure 4 to be discharged from a nozzle orifice N. The bulging portion 91 at the tip of the leak valve 9 is disposed to pass through the inverted-mortar-shaped lip 61. A through-hole diameter D1 of the mortar-shaped valve seat 81 of the valve case 8 is smaller than a nozzle orifice diameter D2.