Patent Application
20080083462
Reference is made in the description to the following briefly described drawings, wherein like reference numerals refer to corresponding elements:
Capsule body 20 has a void 21 in which a sealing member 22 is positioned. The sealing member 22 is preferably made of a moldable grade of fluorinated ethylene propylene (“FEP”), but may be made of, without limitation, other fluorocarbon resins, other plastics or any other suitable material. As will be discussed below, one aspect of the present invention is that the sealing member 22, which is a moving part of the valve 19, is softer than the part against which it seals (in the example shown, it seals against the capsule body 20 to close an opening (or passageway) 26 in the capsule body 20). Sealing member 22 is coupled to a spring 24, which urges sealing member 22 toward the opening 26 to close the valve 19. A stem 28 protrudes from the sealing member 22 and through the opening 26 for interaction with a flexible diaphragm 30. “Stem” refers to any device or component suitable for performing the function of stem 28. A spring 32 is coupled to the flexible diaphragm 30 and urges it downward into contact with the stem 28 so that it pushes sealing member 22 away from opening 26 to open the valve. The space between the diaphragm 30 and the opening 26 is a regulated pressure chamber 34.
In operation, when the pressure in regulated pressure chamber 34 is low enough, the spring 32 is strong enough to overcome the force of spring 24 and push the diaphragm 30 and stem 28 so that sealing member 22 moves away from opening 26. This opening admits gas into the chamber 34, thus increasing pressure in the chamber 34, which in turn forces the diaphragm 30 upward against the spring 32. This eventually reduces the force on the stem 28 sufficiently to allow the spring 24 to push the sealing member 22 against the opening 26 to close the valve 19.
The loading on the diaphragm 30 may be increased or decreased by adjusting the force on the spring 32 at its end opposite of the diaphragm 30, thus changing the regulated pressure setting. The particular pressure regulator 10 illustrated in
Also shown in
The sealing member 22 may include a boss 48 or other structure to facilitate coupling with the spring 24. Spring 24 presses, at the end opposite sealing member 22, on a stop 50, which may be held by the capsule body 20 by swaging open-end 52. Of course, no such stop is needed, and the spring 24 may press against the body 14. Stop 50 may be a sintered brass filter, which has a high porosity, allowing gas to pass into the valve. Other approaches may also be used to allow gas to enter the valve, for example, and without limitation, by not closing the valve, or by providing one or more passageways through the valve body 20.
As shown in
In prior art regulators, the moving part of the valve is made of a relatively hard material, such as brass or stainless steel, and sealed against a stationary soft piece which is generally encapsulated with a metal retainer. With the present invention, the moving part is the softer part. Also, therefore, with the present invention, no such encapsulation is necessary.
Furthermore, by forming the sealing member 22 with a material such as FEP, there is relatively little friction between the sealing member 22 and the inside of capsule body 20, in cases where they come into contact. This is in contrast to prior art systems where the moving piece and the sides of the void in which it travels are metal, and thus its movement can be hindered due to higher friction or scratching.
Furthermore, with the valve 19 discussed above, when formed as an integrated unit (such as, without limitation, by coupling the stop 50 to the valve body 20), assembly and repair of pressure regulators is greatly simplified. In particular, during assembly, the integrated valve 19 is simply coupled to the regulator body 14 (at the valve chamber 18), such as, without limitation, by screwing in using a socket. Thus, the valve body 20 and valve chamber 18 may be threaded. For a failed valve, the bonnet and diaphragm simply need to be removed from the regulator body, and the integrated valve unit is then removed and replaced with a new one. To facilitate easy removal and replacement, the valve body 20 may be formed with a head 52 that accommodates a socket.
Within this description, coupling includes both direct coupling of elements, and coupling indirectly through intermediate elements.
The particular embodiments and descriptions provided herein are illustrative examples only, and features and advantages of each example may be interchanged with, or added to the features and advantages in the other embodiments and examples herein. Moreover, as examples, they are meant to be without limitation as to other possible embodiments, are not meant to limit the scope of the present invention to any particular described detail, and the scope of the invention is meant to be broader than any example. Also, the present invention has several aspects, as described above, and they may stand alone, or be combined with some or all of the other aspects.
And, in general, although the present invention has been described in detail, it should be understood that various changes, alterations, substitutions, additions and modifications can be made without departing from the intended scope of the invention, as defined in the following claims.
