Abstract A dispenser is disclosed for the precise metering of a plurality of viscous fluids, such as the components of an epoxy adhesive in which small amounts to be metered are desired and the proportion of components is critical. The dispenser includes a cartridge, a plurality of pistons operatively located in cylindrical compartments in the cartridge, and means for connecting the ends of the pistons and maintaining the pistons in alignment during dispensing. The cartridge includes a plurality of adjacent cylindrical compartments having adjoining walls, a rear wall at one end of the compartments and having annular openings therein of a diameter equal to the diameter of the respective cylindrical compartments, and forward end closures having orifices leasing through channels to adjacent nozzles. The pistons include a piston drive tab, longitudinal ribs and radial ribs, and a piston head providing sealing means in engagement with the walls of its respective cylindrical compartment. An important aspect is that the longitudinal and radial ribs extend radially from the axis of the piston substantially as far as the radius of the respective cylindrical compartment, in order to reduce the possibility of misalignment of the pistons during dispensing. In addition, misalignment forces are also minimized by the provision of finger tabs on each side of the cartridge spaced equally from the mean thrust axis of the pistons and positioned adjacent to the rear wall of the cartridge.
A dispenser for precisely metered dispensing of small quantities of a plurality of viscous fluids stored therein within segregated compartments, which comprises: a. a cartridge including a plurality of adjacent cylindrical compartments having adjoining walls, a rear wall at one end of said compartments and having annular openings communicating with and of diameter equal to the diameter of the respective compartments, forward end closures for said compartments each having an orifice, leading through a channel to a nozzle; b. a corresponding plurality of pistons of corresponding length to said compartments including a piston drive tab, longitudinal ribs and radial ribs, and a piston head, wherein said piston head provides sealing means in engagement with its respective compartment, and wherein said longitudinal and radial ribs extend radially from the axis of said piston substantially as far as the radius of the respective cylindrical compartment; and c. means for maintaining said pistons in fixed relationship in said compartments throughout the stroke of said pistons comprising means for connecting the piston drive tabs rigidly in a common plane wherein said means is extruded plastic and comprises a rear wall and two front walls defining two grooves for engagement with the edges of said piston tabs.
Claim 2
Dependent Claim
202 words
A dispenser for precisely metered dispensing of small quantities of a plurality of viscous fluids stored therein within segregated compartments, which comprises: a. a cartridge including a plurality of adjacent cylindrical compartments having adjoining walls, a rear wall at one end of said compartments and having annular openings communicating with and of diameter equal to the diameter of the respective compartments, forward end closures for said compartments each having an orifice, leading through a channel to a nozzle; b. a corresponding plurality of pistons of corresponding length to said compartments including a piston drive tab, longitudinal ribs and radial ribs, and a piston head, wherein said piston head provides sealing means in engagement with its respective compartment, and wherein said longitudinal and radial ribs extend radially from the axis of said piston substantially as far as the radius of the respective cylindrical compartment; and c. means for maintaining said pistons in fixed relationship in said compartments throughout the stroke of said pistons comprising means for connecting the piston drive tabs rigidly in a common plane wherein said means is extruded plastic and comprises a rear wall and two front walls defining two grooves for engagement with the edges of said piston tabs.