A two-component piston for a cartridge includes a piston cover as the first component and a piston body as the second component. The piston has a first side and a second side, and a rear side of the piston cover arranged adjacent to at least a part of the piston body. A front side of the piston cover is arranged at the first side, and the rear side of the piston cover includes a valve member. The valve member is to be received within the piston body and to extend into the piston body towards the second side. The piston cover is configured to be moved relative to the piston body on actuation of the valve member and the piston cover is non-releasably connected to the piston body.

A piston includes: a base body; a sealing ring provided at an outer peripheral surface of the base body and configured to slidingly contact an inner peripheral surface of a container; a pressing body provided at one side of the base body in a non-hermetical state with respect to the container, the one side being close to a fluid; and a supporting member supporting the pressing body in a state where the pressing body is separated from the base body. The base body includes an air discharge hole through which an inside and outside of the container communicate with each other, the inside and outside of the container being sealed by the sealing ring. The pressing body can approach and separate from the base body between a first position at which the pressing body opens the air discharge hole and a second position at which the pressing body closes the air discharge hole. The pressing body is supported by the supporting member at the first position and moves to the second position by force applied from the fluid in the container.

A piston assembly including a piston for a cartridge discharging device for discharging a pasty compound out of a cartridge which has an inner wall, having a piston and a rear face which can be acted upon by a pressure plate secured to a push rod, a front face opposite the rear face, and a retaining element which secures the pressure plate against the rear face by a retaining protrusion which covers an edge of the pressure plate in a retaining position. The retaining protrusion is secured to the piston in a movable manner into a release position in a direction away from the push rod.

The present invention relates to a pneumatic glue gun including tank components which contain a glue hose and an injector head; pressure generating units which contain a shell, an extruder, a slidable piston and a push/pull rod; and a drive component connected with the extruder. The tank components are fixed on the shell through a open end of the glue hose and faced the interior space of the shell. The drive component increases the atmospheric pressure between the extruder and the piston by driving the movement of the extruder in the shell, and the piston slides in the glue hose through the increased atmospheric pressure. The glue of the present invention does not need to be replaced, and the glue can be replenished at any time, so the work of replacing the tank is eliminated, and no waste of resources is caused.

Apparatuses and methods related to a high pressure fluid processing device having a dual check valve setup that can be quickly and easily maintained with replacement parts are disclosed herein. In a general example embodiment, a high pressure processing device includes a body including a first surface having a first recess, a second surface having a second recess, and a third surface having a third recess, a first subassembly at least partially inserted into the first recess of the body, the first subassembly including a first check valve, a second subassembly at least partially inserted into the second recess of the body, the second subassembly including a second check valve, and a third subassembly at least partially inserted into the third recess of the body, the third subassembly coupling the body to a fluid driving mechanism, wherein the first subassembly, second subassembly and third subassembly are configured to be independently attachable to and detachable from from the first recess, second recess and third recess, respectively.

An electrically powered handheld dispensing device used to dispense viscous materials from a cartridge in a drip-free manner. The dispensing device having a cartridge locking mechanism that affirmatively locks a material cartridge in place, limiting its axial motion in the cartridge holder. The dispensing device having a plunger assembly containing dogs that bite into the inner surface of the material cartridge piston after a plunger makes contact with the material cartridge piston. The dispensing device having a motor control circuit that automatically reverses the drive motor at high speed to reverse the piston inside the material cartridge to a predetermined distance when the user releases the trigger control, which may also suck material back from the cartridge nozzle tip preventing drips. A manually operated gear-release mechanism disengages the plunger assembly from the gear drive transmission, enabling rapid movement of the plunger in either direction for the loading or unloading of full or partially expended material cartridges.

A mixing device for bone cement comprising a plunger for extruding the mixed material, which plunger is also used as a cover. The plunger has spring blades adapted to be latched on a collar of the housing.

A caulk cartridge for use with high organic solvent caulk is disclosed. The cartridge includes a cartridge body formed as an open-ended elongate cylindrical tube having a first end, a second end, and an inner surface, a nozzle affixed to the first end of the cartridge body, and a plunger engaging with the inner surface of the cartridge body and forming a seal at the second end and slidable along a longitudinal axis of the cartridge body from the second end toward the first end. The cartridge body is manufactured from a cellulosic thermoplastic with a high organic solvent barrier.

Described are metering dispensers having a body configured to hold a flowable composition in a chamber, a drive screw coupled to the body, and a plunger threadingly coupled to the drive screw. The plunger includes at least two annular lips that form a fluid seal with the chamber as the plunger travels along the drive screw through the chamber. A base is rotationally coupled to the body with a cam that contacts at least one tab extending externally from the body so that the tab enters at least one low point on the cam by traveling over a trailing edge of the low point, and the trailing edge then prevents the tab from exiting the low point in the direction of the trailing edge.

A spray applicator assembly discharges distributable product from a cartridge using low air pressure. The cartridge is held captive between a piston advancing from the rear to expel contents and a nozzle snugly attached at the front to receive expelled contents and to convert the contents into droplets by subjecting the contents to an array of focused high velocity air streams. The nozzle has an open barrel design and is able to discharge a variety of liquid or viscous distributable product without readjustment, other than resetting a proportioning valve in the low pressure air feed line. An air chamber immediately in front of the cartridge nose provides constant backpressure, which dominates to cleanly stop flow of distributable product into the nozzle whenever the piston stops advancing. When the piston resumes advancement, the flow restarts cleanly. Clean stopping and starting saves distributable product from waste. Variations in the distributable product might include, without limitation, a broad variety of materials including coating materials and combustibles.