RESERVE GAS SUPPLY METHOD AND APPARATUS BACKGROUND OF THE INVENTION The present invention provides reserve gas supplies for gas-utilizing appliances and vehicles, in particular appliances and vehicles of the type which use containerized gas supplies, for example portable or ambulatory appliances ranging from things such as gas cooking grills to forklift trucks, etc., which operate by use of"LP" (liquid petroleum) gas supplies provided in containers known as"cylinders." Gas appliances and vehicles of the above-mentioned types generally utilize gas supply cylinders of substantial capacity, so as to avoid having to frequently replace the supply cylinder. Cylinder replacement inevitably involves physically unfastening and manipulating the mechanical connectors utilized and lifting the spent cylinder from its mount, lifting the heavy new cylinder into place, and reconnecting the fittings utilized, all of which constitutes a task which is usually onerous and time-consuming.
In order to accomplish this goal of less-frequent replacement, the standard supply cylinders are usually heavy and awkward to lift, move, and install. At the same time, it often happens that the heavy and cumbersome main supply tank located on or at the appliance or vehicle becomes empty at a time when the appliance or vehicle is not physically located near a supply of replacement containers or cylinders. Consequently, replacement becomes a significant problem since the heavy supply cylinders then have to be transported to the appliance or vehicle and replaced there. In the case of an outdoor gas cooking grill, this is not nearly as onerous as in the case something like a forklift truck or automobile, etc., but it is nonetheless inconvenient and for many people quite difficult, particularly where the user is not a physically strong or able person (as in the case of older people, injured or handicapped individuals, etc.). Furthermore, a replacement for the large and heavy main supply tank may not be readily available, particularly if they are expensive and only need replacement on an infrequent basis.
That obviously presents a situation which is likely to be inconvenient at best and perhaps even dangerous at worst.
SUMMARY OF THE INVENTION The present invention provides a solution to the problem discussed above, and does so in the form an easy and conveniently-managed replacement means and method.
More particularly, the present invention apprehends the difficulty and inconvenience of the aforementioned problem which has existed throughout the entire time such gas- utilizing appliances and vehicles have been in use, and provides a convenient and easily implemented alternative. More particularly still, the invention recognizes the fact that small, lightweight LP gas cylinders are already available and are utilized in small appliances or devices that only use a small amount of fuel during their usual time of usage, or which must of necessity be lightweight and portable due to the nature of the appliance or application, and for the first time appreciates that these small lightweight cylinders (most typically, containing only about one pound of liquefied petroleum and being only slightly more than one foot in length and approximately three inches in diameter) provide an ideal temporary supply of gas which can be utilized under emergency or other such unusual conditions.
At the same time, however, the invention apprehends the fact that the conventional uses for such small and lightweight cylinders are substantially different than those for the larger and heavier, cumbersome cylinders referred to above that are used on heavier machinery and the like, and recognizes that prevailing gas safety and utilization standards require the connection fittings utilized for small-cylinder devices to be completely different from those utilized on the larger devices that use large-capacity cylinders, to prevent accidents and injuries resulting from the fact that the large cylinders contain gas under substantially more pressure than is true for the small cylinders and gas appliance suitable for using the small cylinders cannot handle the higher pressures of the larger cylinders. As a result, the small special-purpose cylinders cannot simply be connected to the gas appliance designed for use with larger cylinders, and appropriate safety measures must be employed in any event.
Accordingly, the present invention provides a safe and convenient adapter mechanism by which the aforementioned small, lower pressure cylinders can be connected directly to the gas appliances and/or vehicles which normally use the larger- capacity cylinders, to provide a temporary supply which will enable the appliance or vehicle involved to continue functioning for at least a brief time, during which it can complete any essential task and be moved to the place where the standard large supply cylinder may be changed or refilled directly, without changing. With respect to the desired safety measures, the invention recognizes that the novel adapter mechanism it
provides is inherently incapable of connecting a large-capacity, high-pressure cylinder to a small-capacity user device.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of a typical small LP gas cylinder coupled to a hose with a connector and a coupler embodying a first embodiment the present invention.
FIG. 2 is a front view of a typical small LP gas cylinder coupled to a hose with a connector and a coupler embodying a second embodyment of the present invention.
FIG. 3 is cross-sectional view of the connector and the coupler embodying the first embodiment of the present invention.
FIG. 3A is a cross-section view of a modified connector of the first embodiment of the present invention.
FIG. 4 is cross-sectional view of the connector and the coupler embodying the second embodiment of the present invention.
FIG. 5 is a cross-section view of a connector of a third embodiment of the present invention.
FIG. 6A is a cross-section view of a first component of a connector of a fourth embodiment of the present invention.
FIG. 6B is a cross-section view of a second component of a connector of the fourth embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS For purposes of description herein, and in the appended claims, the terms "upper,""lower,""right,""left,""rear,""front,""vertical,""ho
rizontal,"and derivatives thereof should be understood as relating to the invention as orientated in Fig. 1. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification, are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
The attached figures illustrate two embodiments of the apparatus intended for use with low-pressure equipment such as gas grills and the like, as well as one embodiment
of a device suitable for use with larger machinery such as forklifts or other such vehicles, etc. In the first such case, Figs. 1 and 2 illustrate the outward appearance of the first two alternative embodiments showing a typical small LP gas cylinder 10 coupled to a hose or other such conduit 12 which leads to a gas appliance such as an outdoor cooking grill (not illustrated) in accordance with the invention and by use of the novel connector apparatus 14 (which may be used in each embodiment). In Figure 1, the gas appliance supply conduit 12 is terminated by a coupling 16 which is of a type known as a"CGA 791 Type 1"coupling, which has a manually operable outside connector nut 18 and other parts to be described later. In the embodiment of Fig. 2, the conduit 12 is terminated by a coupler of the type known as a"CGA 510,"designated by the numeral 20, which threads into the connector 14 and has a hexagonal nut-like portion 22 that must be tightened by use of a wrench, as well as a comparable nut 24 included as part of the novel connector 14, on which a similar wrench is utilized to obtain a tight connection.
The interior of the interconnected connector 14 and coupling 16 of Fig. 1 is shown in Fig. 3, which constitutes a central longitudinal section view thereof. As shown there, the coupling 16 will be seen to include the aforementioned manually actuable outer nut 18 and, inside the latter, a standard gas inlet fitting 26 which is conventionally known as"POL"fitting, having a bullet-shaped nose portion 28 and a threaded or otherwise-configured shank or tail portion 30 by which the hose 12 is attached to it. On its inside diametral surface, the nut 18 is formed with appropriate threading (illustrated as having an ACME-Type Thread Profile) 32, that is made to match and connect with complementary threads 34 on the outside of the connector 14, by which the coupling 16 is secured to the connector 14.
Inside connector 14, as further shown in Fig. 3, is a poppet-type valve 36 having a head 38 which is sealable against a corresponding shoulder-like seat 40 and is carried on the end of a valve stem 41 extending toward the right as seen in Fig. 3, terminating with a disk-shaped actuation base 42 against which the forwardmost end of POL fitting nose 28 bears directly as the coupling 16 is engaged with the connector 14 by tightening the outer connector nut 18. As shown in Fig. 3, the internal poppet valve 38 is spring- loaded toward a closed position by a coil spring 44 which bears against an internal shoulder 43 of connector 14 on one end and against a thrust washer 46 or the like
indexed against the inner side of actuator base 42, opposite the surface contacted by POL fitting nose 28. Preferably, the valve assembly 36 is sealed to the inside of connector portion 14 by an O-ring 48 or the like.
When connector 14 and coupling 16 are secured together, by engaging and tightening the nut 18, valve 36 is forced open to permit gas flow through connector 14.
This is accomplished by providing a flow passage which extends through at least a portion of the stem 41 of valve 36 and opens outwardly through the center of actuation base 42, in direct alignment with a comparable passage inside the POL fitting 26 leading to the tail portion 30 thereof and into the interior of hose 12. The inlet to this valve stem passage may conveniently be provided through at least one inlet aperture 50 extending radially from the elongated axial passage to the outside of that portion of valve 36.
The remainder of coupling 14 comprises an adapter fitting 51 having an internally threaded end extremity 53 that is made to screw directly over the threaded outlet end of the small gas cylinder 10, together with an axial passage 55 extending into the area adjacent the head 38 of valve 36. Conventionally, fittings which are made to screw onto a gas cylinder 10, of the type shown in Fig. 1, typically have an internal probe 52, shown in Fig. 3A, that is receivable within a comparable guide opening in the end of the cylinder 10, and such a probe is therefore preferably (but not necessarily) made a part of connector portion 14B, as illustrated. If so used, probe 52 has a central gas flow passage, as is conventionally true, which communicates into the aforementioned chamber adjacent valve head 38. (As will be apparent, Fig. 3A is otherwise the same as Fig. 3.) It is to be particularly noted, that the embodiment of connector 14 shown in Fig.
3 depict connector parts 14A and 14B as being separate from one another, and interconnectable by corresponding threading on the inside of portion 14B and outside of portion 14A, in which case an O-ring or similar such seal 54 is preferably used. At the same time, connector 14 may comprise an integral unit, i. e., portions 14A and 14B being part of the same one-piece unit. Each such embodiment has its own potential advantages, and it is to be noted that component portion 14A is already a commercially available part in and of itself, sold under the trademark"Retro-Q@"by the S. H. Leggitt
Company of San Marcos Texas. Of course, that commercial product is not directly usable as the adaptive coupling unit 14B contemplated by the present invention.
Figure 4 illustrates the alternative embodiment of the connector assembly noted briefly above which is generally illustrated in Fig. 2. Upon close inspection, it will be seen that the connector 14 shown in Fig. 4 is the same as that illustrated in Fig. 3 and described in detail immediately above; however, the coupling portion 20 engaged therewith is of a different type, i. e., that which has long been in use and is known as the standard"510"fitting (another standardized CGA designation). Coupling portion 20 has an inner bullet-nosed POL fitting 126 which is directly comparable to the fitting or fitting portion 26 described above in Fig. 3, but it does not include a manually actuable outer nut and on the contrary has an integral threaded shank 58 which engages complementary internal threads 59 provided in the end extremity of connector portion 14A. Connector portion 20 also carries the integral outside hex nut portion 22 shown and mentioned in connection with Fig. 2, which is tightened by use of a wrench against a like force applied to comparable hex nut portion 24 formed on the outside of the connector 14. Conventionally, a"510"type gas fitting has left-hand threads, to make it unlikely to be engaged with any other device. In all other respects, apart from those just described, the apparatus of Fig. 4 is directly comparable to that of Fig. 3 and the connector 14 is the same and operates in the same manner.
Figure 5 illustrates, in central longitudinal cross-section, a further embodiment 114 of the concept underlying the connector assembly 14 discussed above, in this case particularly configured for use with large-capacity gas-operated devices such as vehicles, in particular, forklift truck vehicles. As in the case of the connector 14 described above, connector 114 is configured so as to be directly attachable to a small, lightweight gas cylinder (for example of the same type referred to above) at one end (shown at the left in Fig. 5, and to be attachable to the conventional connector half employed by the particular vehicle involved as the inlet to its engine fuel inlet, leading to the fuel injectors, etc., (shown at the right in Fig. 5). In the case of forklift trucks, these typically utilize a connector of the type known as a"CGA 790 Style,"which is similar, or at least analogous, to the couplings 16 and 20 referred to above.
As in the case of the coupling embodiment 14 described above, coupling embodiment 114 may optionally be comprised of two parts, designated 114A and 114B
respectively, which are physically configured and sized differently from couplings 16 and 20 but are functionally very similar. As in the case of connector 14, the connector 114 includes an internal poppet valve 136 that is forced off a complementary seat formed by a radially inwardly projecting annular shoulder 140, as illustrated in Fig. 5 (the valve seat and valve face preferably being conically angular, as illustrated). Like valve 26 of coupling 14, valve 136 is forced to move laterally off its seat to permit gas flow past the valve 136 and through the connector by connecting the latter to the coupling part (in this case not specifically shown) attached to the vehicle gas inlet supply, which in the illustrated embodiment is to be secured to the end of coupling part 114B shown at the right in Fig. 5, illustrated as having ACME-Type threading 60 on its outside diameter.
This end of coupling part 114B also has a square-section washer-like seal 62 immediately inside its inlet, and an O-ring seal 64 further downstream, closer to the end of poppet valve 136 (which in this case has a forwardly-projecting actuation stem 136A).
Like valve 26, poppet valve 136 has an actuation spring, designated 144, which normally holds it in a closed position.
In the embodiment illustrated, coupling/connector 114 includes an internal hub 66 which is supported in place by a plurality of mutually spaced inwardly-projecting arms or legs 70 that provide a plurality of annularly disposed gas flow passages 68 between them. The central hub portion 66 has a smooth axial passage at its center through which the projecting stem 141 of valve 136 extends and by which the latter is guided in its opening and closing motions. As already indicated, in other respects, the connectors 14,114 are based on the same underlying concept and are functionally very similar. Also, as illustrated in Fig. 5, the portion 114A of connector 114, which is secured to the small auxiliary supply cylinder contemplated by the invention, includes a concentric, axially extending probe 152, intended for the same purpose as the probe 52 mentioned in the preceding discussion.
Figs. 6A and 6B collectively illustrate a second embodiment 214 of the connector/adapter shown in Fig. 5 and discussed above, which is particularly configured for forklift truck vehicles and the like. In this embodiment, the two component parts of the connector/adapter 214, designated 214A and 214 B, respectively, are directly analogous to the cooperative halves 14A and 14B, 16A and 16B of Figs. 3 and 5, discussed above. Instead of connecting directly together, however, a length of hose 215
(one end of which is shown in Fig. 6A and the other in Fig. 6B) is utilized, in conjunction with a cooperative pair of barbed fittings 270 and 272, which threadedly connect into the cooperative coupling halves 214A and 214B, respectively (as illustrated in the drawings). By utilizing this configuration, the two halves of the connector/adapter 214 may be separated any desired distance from one another rather than threaded directly to each other, or provided as an integral unit, as in the case of the previous embodiments.
Apart from this, the components and operation of embodiment 214 of Figs. 6A and 6B are much the same as those of the preceding embodiments, particularly the embodiment 114 shown in Fig. 5. Thus, the component part 214A includes a poppet valve 236 which is directly analogous to the poppet 136 of the Fig. 5 embodiment, with a similar central hub structure 266 for supporting the slidable valve stem (oriented toward the right as shown in Fig. 6A), together with a coil spring 244 which normally holds valve 236 in a closed position (the valve being showed open in Fig. 6A, with coil spring 244 compressed). In this case, the part designated 216 and shown at the extreme left in Fig. 6A comprises a part of the conventional forklift truck connector (known as a CGA790 connector), which includes a cylindrical internal piston-like member 228 that engages the stem portion of valve 236 which extends toward the left, to bear against the latter and force valve 236 to an open position as connector 216 is threadedly tightened with respect to connector/adapter 214, by means of an ACME thread connection much like that shown and described above. As in the case of the outer nut 18 of the Fig. 3 embodiment, the connector 216 includes a nut portion 218 which is rotatably secured to that portion of component 228 which is oriented to the leftmost extremity of Fig. 6A, and is rotatably attached thereto. Other directly analogous feature of connector/adapter 214, comparable to connector 114 of Fig. 5, will no doubt be apparent to those skilled in the art.
The purposes, objectives, and advantages of the invention will be understood by those skilled in the art following consideration of the foregoing description and attached drawings. Furthermore, it is understood that use of the term"gas"in this application refers to a gas or liquid, i. e., a fluid. Of course, the above description is addressed to the preferred embodiments only. Modifications of these embodiments may occur to those skilled in the art and to those who make or use the invention, without departing from the underlying invention itself. Therefore, it is to be understood that the particular embodiments shown in the drawings and described above are merely for illustrative purposes and these should not be interpreted as limiting the scope of the invention.
