Patent Application
20100213217
This invention relates generally to the field of dispensing liquid materials and, more specifically, to dispensing assemblies.
Various types of dispensers are used in many industries for placing liquids, such as adhesives, conformal coating materials, solder paste, solder flux, and similar materials onto substrates during an assembly process or other processes. One type of liquid dispensing assembly includes a body defining a cartridge with a reservoir for holding a supply of liquid to be dispensed. An end fitting, such as a syringe dispensing tip or other fitting, is coupled to the cartridge at one end and communicates with the reservoir. A piston disposed in the reservoir is movable to pressurize the liquid in the reservoir and thereby dispense the liquid onto a substrate.
Typically, the end fitting, such as the syringe dispensing tip, is coupled to a connector portion of the cartridge with a rotational connection. For example, this connection is typically a threaded type of connection. In order to securely rotate the end fitting onto the connector portion of the cartridge, the user often tightly grips the connector portion of the cartridge with a tool such as a pair of pliers. This can cause undesirable stress on the cartridge and can make coupling of the end fitting to the cartridge difficult. In addition, the cartridge is typically held in a retainer, which is also generally cartridge-shaped or cylindrical. A retaining cap is then used at the end of the retainer opposite to the tip to securely hold the cartridge in place. The retaining cap also provides an input port for pressurized fluid, such as air, used to move the piston. Oftentimes, when rotating end fittings onto the connector portion of the cartridge, which extends through an open end of the retainer, the cartridge will tend to rotate within the retainer. This further exacerbates the problem of tightening the end fitting.
The present invention, in one illustrative embodiment, generally comprises a dispensing assembly including a cartridge and a retainer. The cartridge has a dispensing end and defines a reservoir therein for holding a liquid. The dispensing end includes a connector portion for receiving an end fitting with a rotational connection. The retainer includes a first open end and receives the cartridge such that the connector portion communicates with the first open end in a manner allowing connection of the end fitting. The retainer is coupled with the cartridge in a manner preventing relative rotation between the cartridge and the retainer.
Among other aspects that may be incorporated into the dispensing assembly, for example, the connector portion may include internal threads for mating with external threads associated with the end fitting. The internal surface at the first open end of the retainer can mate with the outer surface of the connector portion in the manner mentioned above, i.e., a manner preventing relative rotation between the cartridge and the retainer. For example, the internal surface at the first open end and the outer surface of the connector portion may have mating sections, such as the flat sections of a hexagon. The dispensing assembly may further comprise a cap that releasably mates with a second open end of the retainer. Although the dispensing assembly may take various forms, for example, the cartridge may further include a piston. In this case, the cap may include an input port for receiving a pressurized fluid and directing the pressurized fluid into the reservoir to move the piston in order to dispense the liquid.
Various additional features and advantages will become apparent upon review of the following detailed description of an illustrative embodiment, taken in conjunction with the accompanying drawings.
Referring to
The retainer 14 includes a first open end 34 and a second open end 36. The retainer 14 receives the cartridge 12 such that the connector portion 26 communicates with the first open end 34 in a manner allowing connection of the end fitting 30. In the illustrated embodiment, for example, the connector portion 26 extends through the first open end 34 such that it is exposed as shown in
A coupling is made between the cartridge 12 and the retainer 14 such that relative rotation between the cartridge 12 and the retainer 14 is prevented. In the illustrated embodiment, this coupling takes the form of a hexagonal outer surface defined by flat sections 40 on the connector portion 26 and a corresponding internal hexagonal surface defined by flat sections 42 at the first open end 34 of the retainer 14. Thus, as will be appreciated by reviewing
The cap 16 includes connecting structure 52 configured to rotationally engage, tighten and lock with corresponding connecting structure 54 at the second open end 36 of the retainer 14. Thus, the cap 16 may be tightly connected, locked and sealed on the retainer 14 as shown in
While the present invention has been illustrated by a description of an embodiment and while this embodiment has been described in some detail, it is not the intention of the Applicants to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The various features discussed herein may be used alone or in any combination depending on the needs and preferences of the user. This has been a description of illustrative aspects and embodiments the present invention, along with the preferred methods of practicing the present invention as currently known. However, the invention itself should only be defined by the appended claims. What is claimed is:
