Abstract:
A switchover manifold for selectively connecting one of a plurality of compressed gas vessels to a point of use such that the supply of compressed gas remains uninterrupted even as the compressed gas vessels are opened and closed to the point of use for renewal of depleted compressed gas vessels. The switchover manifold has an inlet for each gas vessel all in communication with a utilization outlet, and an externally operated valve which opens only one compressed gas vessel to the utilization outlet at any one time. The manifold may be utilized in conjunction with a gas bottle cart. The gas bottles may be medical side D bottles being used in association with a medical procedure comprising insufflation.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to control of medical gases being dispensed from plural gas storage tanks, and more particularly to an apparatus which both enables plural tanks to be connected together and also enables a user to select which tank is actively connected to medical apparatus which uses the stored medical gases. 
       BACKGROUND OF THE INVENTION 
       [0002]    Medical procedures may utilize medical gases which are stored under pressure in dedicated pressure vessels. One example is insufflation apparatus which may be connected to a compressed gas bottle or other dedicated vessel. 
         [0003]    As a medical procedure progresses, the gas may become depleted. It may be inefficient if not hazardous to a procedure should the patient become deprived of medical gas. It is undesirable to interrupt a medical procedure to disconnect and replace a depleted compressed gas bottle. There exists a need to be able to renew compressed gas bottles without interrupting a medical procedure. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention provides a manifold which enables immediate switchover of gas supply from one compressed gas bottle to another, while maintaining the supply of compressed gas uninterrupted. Also, the switchover manifold is provided with pressure gauges arranged to indicate immediately and readily the remaining pressure and hence volume of contents for each of several compressed gas bottles connected thereto. The switchover manifold has for example a three way valve arranged to make active connection of any one selected compressed gas bottle to that apparatus which actually utilizes the compressed gas. 
         [0005]    The switchover manifold may be mounted on a gas bottle cart to support medical gases for example. The gas bottles may be size D medical gas bottles. The associated procedure may be a medical procedure such as surgery, comprising a step of insufflation utilizing a gas supply the continuity of which is assured by utilization of plural gas bottles which may be connected to the switchover manifold and periodically replaced without interrupting the medical procedure. 
         [0006]    It is an object of the invention to provide a way of replacing depleted compressed gas bottles in the course of a medical procedure without discontinuing the supply of compressed gas from the medical procedure. 
         [0007]    It is an object of the invention to provide improved elements and arrangements thereof by apparatus for the purposes described which is inexpensive, dependable, and fully effective in accomplishing its intended purposes. 
         [0008]    These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
           [0010]      FIG. 1  is a side view of apparatus of the invention. 
           [0011]      FIG. 2  is an exploded, enlarged side detail view of the top of  FIG. 1 . 
           [0012]      FIG. 3  is an enlarged side view of the central component of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Referring first to  FIGS. 1 and 2 , according to at least one aspect of the invention, there is shown apparatus  100  for enabling a compressed gas supply to remain continuously available to a procedure which utilizes compressed gas, while enabling replacement of depleted compressed gas storage vessels in the course of the procedure without resulting in any interruption to the supply of compressed gas to the procedure. An advantageous example of a procedure which benefits from the invention is a surgical procedure requiring insufflation, although obviously, other procedures may also utilize the invention. 
         [0014]    The apparatus  100  may comprise a first compressed gas storage vessel  102  containing a gas and at least one second compressed gas storage vessel  104 . As employed herein, the terms “compressed gas storage vessel” and “gas bottle” will be utilized interchangeably, unless context dictates otherwise. Because the invention contemplates assuring a constant supply of gas, it follows that the gas contained within the first and second gas storage vessels  102 ,  104  will be identical or alternatively, functionally equivalent. The compressed gas storage vessel  102  may be a conventional compressed gas bottle having a mechanical connector  106  adapted to establish a delivery path for compressed gas stored within the first compressed gas storage vessel  102 . The compressed gas storage vessel  104  may have the same functional and structural features. 
         [0015]    Gas obtained selectively from one of the compressed gas storage vessels  102  or  104  is discharged to a utilization hose  110  which may be part of or may be connected to an insufflator (not shown) or other apparatus using the gas being dispensed. The reason for selective discharge of gas is to facilitate replacement of the compressed gas storage vessels  102 ,  104  as each becomes depleted. Depletion may signify that pressure falls below a predetermined pressure value, and thus the gas may not be fully exhausted when it is regarded as depleted. To this end, only one compressed gas storage vessel  102  or  104  is actively placed in communication with the utilization hose  110 , while the remaining compressed gas storage vessel  104  or  102  is mechanically connected, but in a manner in which gas contained therein is not in communication with the utilization hose  110 . 
         [0016]    Actual communication between the compressed gas storage vessels  102 ,  104  and the utilization hose  110  is managed by a switchover manifold  108  which is disposed to establish flow paths from the first compressed gas storage vessel  102  and the second gas storage vessel  104  to the point of use or to conduits ultimately leading to the point of use. The switchover manifold  108  comprises a body  118  which may incorporate an internal three-way or “tee” shaped passage which extends to a first supply inlet  112  associated with the compressed gas storage vessel  102 , a supply inlet  114  which is associated with the compressed gas storage vessel  104 , and the utilization hose  110 . The body  118  serves as a structural member which defines the internal passage and which supports other functional components of the switchover manifold  108 . The switchover manifold  108  also comprises an internal selector valve (not visible) which is movable between a first position and at least a second position. In the first position, the selector valve is disposed to establish fluid communication selectively between the first supply inlet  112  and a utilization outlet  116  and to obstruct fluid communication between the second supply inlet  114  and the utilization outlet  116 . In the second position, connection logic is reversed, the selector valve establishing fluid communication selectively between the second supply inlet  114  and the utilization outlet  116 , and obstructing fluid communication between the first supply inlet  112  and the utilization outlet  116 . 
         [0017]    It may be mentioned here that the terms “supply inlet” and “utilization outlet” are conceptual rather than necessarily referring to specific apparatuses or portions of the switchover manifold  108  in that these terms designate function. Obviously, communication and obstruction functions could proceed as described even with different apparatus utilized or interposed between or among the various recited elements of the invention. Illustratively, the switchover manifold  108  may be connected to or terminate at mechanical connectors such as tee fittings  120 ,  122 , each of which has an internal three-way or “tee” shaped passage (not shown) so as to enable connection of the switchover manifold  108  to respective hoses  124 ,  126 , which in turn conduct gas from compressed gas storage vessels  102 ,  104  to the switchover manifold  108 . Each hose  124  or  126  is matingly compatible with the mechanical connector of its associated compressed gas storage vessel  102  or  104 , and with respective supply inlets of the switchover manifold  108 , such as the tee fittings  120 ,  122 . 
         [0018]    The tee fittings  120 ,  122  may be provided as separate components which for example thread to the body  118 , may be integral to the body  118 , or may be provided in other ways. The tee fittings  120 ,  122  enable respective pressure gauges  128 ,  130  to be mounted to the switchover manifold  108  and connected to the internal passage of the switchover manifold  108  so as to be in fluid communication with the supply inlets  112 ,  114  and to monitor and annunciate pressure at each of the supply inlets  112 ,  114 . It will be seen in  FIGS. 1 and 2  that pressure gauges  128 ,  130  face the same direction and are thereby readily read by an observer. It will also be seen that the switchover manifold  108  is generally bilaterally symmetrical about a hypothetical plane indicated by a projection line  136  which bisects the utilization outlet. The hypothetical plane indicated by the projection line  136  is perpendicular to the plane of the drawing of  FIG. 2 . “Generally bilaterally symmetrical” signifies that the components are arranged in mirror image on both sides of the hypothetical plane, apart from the readouts of the pressure gauges  128 ,  130 . Rather than literally being symmetrical, the gauges may be arranged with their readouts or gauge faces both arranged to read right to left, for example with zero values displayed at the lower left of each scale of the respective pressure gauge  128 ,  130 . This enables immediate intuitive comprehension of pressure values being displayed by the pressure gauges  128 ,  130 , which would be complicated were the readouts of the pressure gauges  128 ,  130  literally mirror images of one another. 
         [0019]    Hoses  124 ,  126  may have respective integral threaded connectors  132 ,  134 , or may comprise separate elements (not shown) to enable connection and performance as described. The same applies to the utilization hose  110 , which may connect to or terminate at a mechanical connector of the  116 , such as the threaded stub  134 . 
         [0020]    The various mechanical connectors of the compressed gas storage vessels  102 ,  104  described herein are manually connectable to the switchover manifold  108  in a way which establishes fluid-tight continuity from each of the compressed gas storage vessels  102 ,  104  to the internal passage of the switchover manifold  108 . Fluid-tight continuity signifies that compressed gases being supplied will not leak to an objectionable extent under conditions of normal use. Threaded connections, which may for example be sealed by conventional sealing tape, fluent sealing substances, and the like, are described in illustrative capacity, although other connection schemes may be provided. 
         [0021]    Best seen in  FIG. 2 , the selector valve comprises an external operating handle  138  which is disposed to move the valve (not shown, but which may be any suitable known type) between the first position and the at least second position. The operating handle  138  may comprise a pointer  140  disposed to point towards the first supply inlet  112  when the first supply inlet  112  is in fluid communication with the utilization outlet  116  and to point towards the second supply inlet  114  when the second supply inlet  114  is in fluid communication with the utilization outlet  116 . Preferably, the operating handle  138  moves through a partial rotation of one hundred eighty degrees (indicated by an arrow  140 ) when moving between the first position and the second position. The operating handle  138  may project from the body  118  of the switchover manifold  108  in the same direction as that of the first pressure gauge  128  and the second pressure gauge  130 , so that the pressure gauges  128 ,  130  and the operating handle  138  may be conveniently viewed from one perspective. 
         [0022]      FIG. 2  also shows three tabs  144 ,  146 ,  148  each bearing respective holes  150 ,  152 ,  154  for receiving and retaining a fastener such as a bolt (not shown) to enable mounting of the switchover manifold  108  to a gas cart (not shown), such as an insufflation equipment cart or a gas bottle cart. 
         [0023]    Turning now to  FIG. 3 , the invention may be thought of as only the switchover manifold  108 , which is disposed to establish flow paths selectively from a first compressed gas source and a second compressed gas source to a point of use. That is, when thought of as only the switchover manifold  108 , elements such as conduits such as the hoses  124  and  126  and even gauges such as the gauges  128  and  130  may be omitted. Considered in this way, the invention may be limited to the body  118  in which is defined an internal passage including a first inlet conduit  160 , a second inlet conduit  162 , and a utilization conduit  164 , wherein the internal passage is configured to establish fluid communication among the first inlet conduit  160 , the second inlet conduit  162 , and the utilization conduit  164 ; a selector valve (of which only a stem  166  is seen, in end view in  FIG. 3 ), and at least one projecting tab bearing at least one hole for receiving and retaining a fastener to enable mounting of the switchover manifold  108  to a gas cart. Although  FIGS. 2 and 3  show each tab as bearing one such hole, it would be possible to provide one or more tabs bearing more than one hole. Also, the body  118  may be redesigned such that one or more holes for receiving a fastener is formed in the body in the absence of a discernible, discrete tab such as the tabs  142 ,  144 ,  146 . 
         [0024]    The selector valve may of course be the structural and functional equivalent of the valve of the switchover manifold  108  of  FIG. 2  for example, and further may include a handle such as the external operating handle  138 . The selector valve may be arranged such that the operating handle represented by the valve stem  166  moves through a partial rotation of one hundred eighty degrees when moving between the first position and the second position. 
         [0025]    The switchover manifold may include one or more pressure gauges such as the pressure gauges  128  and  130 , connected thereto such as by a threaded connection, or formed integrally with a body such as the body  118  redesigned from that shown herein for such a modification, while still omitting the hoses  124  and  126 . 
         [0026]    The apparatus  100  may be utilized to implement a method of operating a medical gas supply provided by more than one compressed gas storage vessel while conducting a medical procedure. The method may comprise the steps of: 
         [0027]    providing at least two compressed gas storage vessels such as the compressed gas storage vessels  102 ,  104  each connected in common to a manifold such as the manifold  108  having a utilization outlet  116 , and a valve disposed to open one of the at least two compressed gas storage vessels  102 ,  104  to the utilization outlet  116  while closing all other ones of the compressed gas storage vessels to the utilization outlet  116 ; 
         [0028]    opening a first one of the compressed gas storage vessels  102 ,  104  to the utilization outlet  116  while the medical procedure is being conducted and is utilizing gas obtained from the utilization outlet  116 , using the valve; 
         [0029]    in a manual operation, operating the valve to close the first one of the compressed gas storage vessels  102 ,  104  to the utilization outlet  116  of the manifold  108  when the first one of the compressed gas storage vessels  102 ,  104  becomes depleted to a predetermined degree, while in a continuum of movement during the same manual operation, opening another one of the compressed gas storage vessels  102 ,  104  to the utilization outlet  116  of the manifold  108 . 
         [0030]    The method recited above may comprise a further step of replacing the first one of the compressed gas storage vessels  102  or  104  with a fully charged compressed gas storage vessel (not shown, but which may be similar to the compressed gas storage vessels  102 ,  104 ) while simultaneously conducting the medical procedure. 
         [0031]    The method may comprise a still further step wherein the step of conducting a medical procedure comprises a step of practicing insufflation using gas supplied by the compressed gas storage vessels. 
         [0032]    The present invention is susceptible to variations and modifications which may be introduced thereto without departing from the inventive principles. In one non-limiting example, although the invention has been described in terms of two compressed gas vessels  102 ,  104 , it would be possible to modify the invention to accommodate more than two such vessels. In another non-limiting example, it would be possible to configure a manifold (not shown) which is similar in function to the manifold  108  such that the connection points serving the compressed gas storage vessels  102 ,  104  are spaced apart and directed so as to accommodate direct connection of the compressed gas storage vessels  102 ,  104  to the manifold, thereby eliminating the hoses  124 ,  126 . 
         [0033]    While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is to be understood that the present invention is not to be limited to the disclosed arrangements, but is intended to cover various arrangements which are included within the spirit and scope of the broadest possible interpretation of the appended claims so as to encompass all modifications and equivalent arrangements which are possible