BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an illustration of a PTC cartridge to be inserted into a housing of a pneumatic device.
FIG. 2 is an illustration of the PTC cartridge according to FIG. 1 inserted into the housing of the pneumatic device.
FIG. 3 is an enlarged view of the connection between the PTC connector and the component.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views.
FIGS. 1 and 2 illustrate a pneumatic device assembly 10, in which a Push To Connect (PCT) fitting cartridge 12 is illustrated. As seen in FIG. 1, PCT cartridge 12 is insertable into port 14 of pneumatic device 16, which may include, for example, a pneumatic brake and a pneumatic height control valve.
The PCT cartridge 12 is provided having a generally cylindrical diameter, but may, be provided with virtually any type of cross-section. PCT cartridge 12 is illustrated in FIG. 1 generally having a cross-section diameter (d).
PCT cartridge 12 is further illustrated in FIG. 1 having a cartridge shoulder 28, which is defined having a cross-section diameter (d1). As can be seen in FIG. 1, cartridge shoulder 28 extends out beyond outer surface 26 of the PCT cartridge 12, such that, diameter (d1) is larger than diameter (d).
PCT cartridge 12 is further illustrated having a tube 18 connection, which is illustrated in FIGS. 1 and 2. Tube 18 may couple to PCT cartridge 12 by means of a tube cavity 20, which extends from a distal end 22 of PCT cartridge 12. Tube cavity 20 is provided for receiving pneumatic tube 18 therein, the tube 18 coupled to the port 14 via the PCT cartridge 12. Tube 18 is provided such that, pressurized air may be selectively introduced and/or exhausted from the pneumatic device 16 via the tube 18.
Referring now to port 14 of pneumatic device 16, port 14 is provided having a generally cylindrical diameter and is provided with an inner surface 24 that is designed to receive outer surface 26 of the PCT cartridge 12 in relatively close fit. The inner surface 24 of port 14 is illustrated having a cross-section diameter (d2).
In this manner, it is a relatively simple matter to insert PCT cartridge 12 into port 14 to couple tube 18 to pneumatic device 16 as is illustrated in FIG. 2.
Port 14 is further provided with a port shoulder 30, which is designed to abut cartridge shoulder 28 of PCT cartridge 12 as shown. As can be seen, port shoulder 30 is provided with a beveled section 32 to simplify the insertion of PCT cartridge 12.
Port shoulder 30 is provided such that, when PCT cartridge 12 is inserted therein, PCT cartridge 12 is steadied and securely maintained therein. Cartridge shoulder 28 is also provided as a stop for PCT cartridge 12 when cartridge shoulder 28 abuts up against port shoulder 30. As can be seen, the cross-section diameter (d1) of cartridge shoulder 28 is larger than the cross-section diameter (d2) of the inner surface 24 of port 14.
As seen in FIG. 2, tube 18 may be inserted in to tube cavity 20 via tube cavity opening 34. Tube cavity opening 34 is indicated as having an opening with a cross-section diameter (d3), while tube cavity is shown having a cross-section diameter (d4), where diameter (d3) is larger than diameter (d4). In this manner, tube 18 encounters a beveled edge at tube cavity opening 34 to facilitate insertion of tube 18 in cavity opening 34.
Referring now to FIG. 3, an enlarged view of a section of FIG. 2 is illustrated, which shows PCT cartridge 12 inserted in port 14, and more particularly, the interaction of PCT cartridge 12 with the inner surface 24 of port 14.
As shown in FIG. 3, outer surface 26 of the PCT cartridge 12 is provided with protrusion(s) 36, which in this embodiment are provided as teeth to engage with inner surface 24. Also illustrated in FIG. 3 is undercut 38, which is situated on inner surface 24 of port 14. Undercut 38 is provided to engage with protrusion(s) 36 such that, upon advancement of PCT cartridge 12 into port 14, a snap fit occurs and an interlock is developed. For example, the cross-section diameter (d) of PCT cartridge 12 is provided slightly larger than the cross-section diameter (d2) of the inner surface 24. Therefore, advancement of PCT cartridge 12 into port 14 will generate “hoop” stress on the surrounding material as the protrusion(s) 36 are slightly deflected radially inward. However, as the protrusion(s) 36 advance past undercut 38, the protrusion(s) 36 is then able to expand radially outward again thereby reliving any “hoop” stress temporarily encountered by port 14.
It may also be seen from FIG. 3, that an O-ring 40 is provided in a channel 42, which is positioned between the inner surface 24 and the PCT cartridge 12. In this manner an air-tight seal may be created between PCT cartridge 12 and port 14. It is contemplated that O-ring 40 may comprise any type of material as desired for the application, but typically will comprise a pliable elastic material, such as, for example, rubber.
It can be seen from FIG. 3 that the interlock created between PCT cartridge 12 and port 14 creates a highly secure connection, which will not easily be interrupted. This is very advantageous as the coupling will not loosen or disconnect due to, for example, vibration.
It may however, become necessary to disconnect PCT cartridge 12 for servicing, replacement, etc. As an interlock has been created between PCT cartridge 12 and port 14, simply applying withdrawing pressure may not detach the PCT cartridge 12 from port 14. Accordingly, detaching means are provided in the form of cartridge shoulder 28, which may be deflected radially inward to as to disengage protrusion(s) 36 from undercut 38. In this manner, PCT cartridge 12 may then be easily withdrawn from port 14.
In this manner, a highly engineered grade plastic PTC fitting cartridge may effectively be used for connection of air tubes or conduits to an air brake or height control valve. Therefore, the present system allows for the speed and convenience of PTC fittings to be taken advantage of, while at the same time, any stress encountered by the surrounding material is substantially eliminated to avoid fracture of the surrounding material.
Although the invention has been described with reference to a particular arrangement of parts, features and the like, these are not intended to exhaust all possible arrangements or features, and indeed many other modifications and variations will be ascertainable to those of skill in the art.
Patent Application
20080012318
