Abstract:
A dual chamber coolant reservoir having a single vent neck. The coolant reservoir is for an internal combustion engine cooling system wherein the reservoir housing includes a first chamber and a second chamber formed integral thereto. A vent neck includes an aperture for accessing the first chamber with either a two or three o-ring cap to maintain pressure within the first chamber. Means for venting the second chamber when coolant exceeds a predetermined pressure level and a means for venting the first and second chamber when said cap is moved from a closed position to an open position. An inline pressure relief valve and check valve providing pressure relief and air displacement.

Description:
PRIORITY CLAIM 
       [0001]    In accordance with 37 C.F.R. 1.76, a claim of priority is included in an Application Data Sheet filed concurrently herewith. Accordingly, the present invention claims priority to U.S. Provisional Patent Application No. 62/088,991, entitled “DUAL CHAMBER COOLANT RESERVOIR”, filed Dec. 8, 2014. The contents of the above referenced application is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention is directed to the field of cooling systems for internal combustion engines and all fluid cooled equipment in particular to a dual chamber coolant reservoir having a single vent neck. 
       BACKGROUND OF THE INVENTION 
       [0003]    Internal combustion engines convert chemical energy, such as gasoline, into mechanical energy. An internal combustion engine compresses a mixture of air and gasoline within a cylinder by use of a piston coupled to a crankshaft. The piston is rotated into a position so as to cause an increase in the mixture density, temperature, and pressure within the cylinder wherein a high voltage electric spark causes the mixture to expand rapidly resulting in movement of the piston. As the piston is moved a connecting rod imparts a linear to rotational movement of the crankshaft to produce the mechanical energy. 
         [0004]    The operation of the internal combustion engine involves many parts which produces heat from friction. Excess heat must be removed for engine longevity. However, for efficient operation the internal combustion engine must operate at a predetermined temperature. For this reason, most engines on a vehicle require a cooling system to regulate the engine temperature. Conventionally a radiator is located in the front of the vehicle and positioned transverse to the direction of movement of the vehicle. A radiator fan is then employed to draw air through the radiator so that cooling may be effected when the vehicle is operating at a speed where insufficient air is being driven through the radiator. 
         [0005]    A coolant reservoir, also referred to as a coolant recovery tank, allows coolant such as a mixture of water and antifreeze to reside as it expands when heated. The coolant reservoir is typically made of plastic and constructed to allow an operator to visually check the level and condition of the coolant. Conventional coolant systems are sealed and placed under pressure. Late model vehicles pressurize the coolant reservoir essentially eliminating the need for the traditional radiator cap fill port. In this embodiment the cooling system recirculates coolant through the engine and into the radiator for dispersion of excess heat. Should the coolant become heated to the point of expansion, the coolant will expand into the coolant reservoir. This typically occurs when the engine has been turned off immediately after operating. The recirculation discontinues and the coolant reservoir accepts the expansion. As the cooling process takes place after engine shutdown, the coolant begins to shrink within the engine and creates a vacuum that draws the coolant from the reservoir back into the radiator and engine portion of the cooling system. Still more recent engines employ a dual chamber reservoir having a pressurized chamber formed integral with an overflow chamber. Such reservoirs have a pressure relief cap and a fill port cap. The problem with such systems is the cost of manufacturing a dual neck reservoir to hold two caps. Further, the caps are rated at different pressures so there is a possibility of attaching the wrong cap to the vent neck. For instance, one cap may have pressure relieve and the second has no relief. In addition, a second cap located on a coolant reservoir would be located along a side of the reservoir making it very difficult to service. 
         [0006]    What is needed in the art is a dual chamber coolant reservoir wherein a single vent neck can be used for coolant insertion and pressure relief. 
       SUMMARY OF THE INVENTION 
       [0007]    Disclosed is a dual chamber coolant reservoir having a single vent neck. The coolant reservoir is for an internal combustion engine cooling system wherein a reservoir housing includes a first chamber and a second chamber formed integral thereto. The first chamber is fluidly coupled to the second chamber by a strategically positioned first trough. A vent neck includes an aperture for accessing the first chamber with a multiple o-ring cap to maintain pressure within the first chamber. Means for venting said second chamber when coolant within the second chamber exceeds a predetermined pressure level and a means for venting said second chamber when said cap is moved from a closed position to an open position. An inline pressure relief valve and check valve providing pressure relief and air displacement. 
         [0008]    An objective of the invention is to disclose a coolant reservoir that eliminates the need for a second vent neck and second vent cap. 
         [0009]    Still another objective of the invention is to eliminate the need for servicing a reservoir having a side cap or accidentally switching the two caps. 
         [0010]    Yet still another objective of the invention is to employ a single sealing cap mounted in an easily accessible position along the top surface of the reservoir using an inline valve for pressure relief, and an inline check valve for air displacement. 
         [0011]    Still another objective of the invention is combine the functions of the pressure relieving neck through the fill cap by inclusion of an inline pressure relief valve and check valve allowing expanding fluid to be relieved while allowing air back into the reservoir without restriction. 
         [0012]    Another objective of the invention is to teach the use of a cap mounted pressure relief valve and check valve assembly allowing a single vent port in the vent neck. 
         [0013]    Other objectives and further advantages and benefits associated with this invention will be apparent to those skilled in the art from the description, examples and claims which follow. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  illustrates a front view of a prior art two cap coolant reservoir; 
           [0015]      FIG. 2  illustrates a rear view of  FIG. 1 ; 
           [0016]      FIG. 3  illustrates a single cap coolant reservoir of the instant invention; 
           [0017]      FIG. 4  illustrates the single cap coolant reservoir having a three o-ring design placed in a closed position; 
           [0018]      FIG. 5  illustrates the single cap coolant reservoir with the cap having a first o-ring disengaged; 
           [0019]      FIG. 6  illustrates the single cap coolant reservoir with the cap having a second o-ring disengaged; 
           [0020]      FIG. 7  illustrates the single cap coolant reservoir with the cap having the third o-ring disengaged; 
           [0021]      FIG. 8  illustrates the three o-ring cap hose routing with in-line pressure relief; 
           [0022]      FIG. 9  illustrates the three o-ring cap hose routing with in-line pressure relief if a single valve cannot be used; 
           [0023]      FIG. 10  illustrates a single cap coolant reservoir with a two o-ring seal; 
           [0024]      FIG. 11  illustrates the two o-ring single cap coolant reservoir with the cap closed; 
           [0025]      FIG. 12  illustrates the two o-ring single cap coolant reservoir with the first o-ring disengaged; 
           [0026]      FIG. 13  illustrates the two o-ring single cap coolant reservoir with the second o-ring disengaged; 
           [0027]      FIG. 14  illustrates a three o-ring single cap coolant reservoir with an internal relief valve and check valve; 
           [0028]      FIG. 15  is a further depiction of  FIG. 14  illustrating pressure release; 
           [0029]      FIG. 16  illustrates the three o-ring single cap coolant reservoir with the first o-ring disengaged; 
           [0030]      FIG. 17  illustrates the three o-ring single cap coolant reservoir with the second o-ring disengaged; and 
           [0031]      FIG. 18  illustrates the three o-ring single cap coolant reservoir with the third o-ring disengaged. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0032]    Detailed embodiments of the instant invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific functional and structural details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representation basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. 
         [0033]    Coolant systems used in more recent engines pressurize the coolant reservoir. By way of example,  FIGS. 1 and 2  illustrate a prior art coolant reservoir  10  which includes a container having an upper fluid reservoir  12  and a lower fluid overflow  14 . Excess coolant is relieved from the upper fluid reservoir  12  through an overflow channel  16 . In operation, when the engine cools down, the engine will form a vacuum that draws coolant from the lower fluid overflow  14  back into the upper fluid reservoir  12 . In addition, a pressure relief trough  18  is employed. If a cap placed upon the top fill neck  20  is opened while the coolant is hot, air pressure is relieved through the overflow channel  18  and air will escape out of the overflow port  22  instead of spraying the individual opening the cap. A vent neck  24  is positioned along the side of the reservoir with a pressure relief vent cap, not shown, placed on the vent neck  24  for sealing of the pressurized system. A relief hole  26  releases pressure through the pressure relief cap and through the vent neck port  28 . The vent neck  24  uses a conventional two o-ring cap wherein pressure in excess of 20 psi can be released from the reservoir, or any pressure of design. 
         [0034]    Referring to  FIG. 3 , set forth is the coolant reservoir  50  of the instant invention having a single vent neck  52 . Noticeably absent is the second vent neck, typically located along the lower side surface  54  of the reservoir. In this embodiment, a pressure relief port  56  is positioned alongside a venting port  58 . Venting port  58  is fluidly coupled to a check valve  60 . 
         [0035]      FIG. 4  depicts the vent neck  52 , wherein pressurized air from the fluid overflow second chamber  51  of the reservoir  50  is directed through the trough  78  passing between the first o-ring  64  and second o-ring  66  to venting port  80 . The cap  62  in this embodiment is a three o-ring design, having a first o-ring  64 , a second o-ring  66  and third o-ring  68 . When the cap is closed, as illustrated, the o-rings  64 ,  66  and  68  seal between the cap surface and stepped side walls  72 ,  74  and  76 . Pressurized air that enters the vent neck  52  from the second chamber into the port  78  would be directed through the venting port  80 , that will include a pressure relief and check valve, that allows 20 psi pressure and above to escape. There is no restriction for air to be drawn back into the reservoir. 
         [0036]    Referring to  FIG. 5 , cap  62  has been rotated to a position where the first o-ring  64  disengages stepped side wall  74 , wherein pressurized air from the lower section  51  of the reservoir  50  is allowed to vent through the trough  78  to the overflow port  82  uninhibited, thereby releasing air pressure from inside the reservoir to the atmosphere. It is noted that the second o-ring  66  and third o-ring  68  remain engaged between side wall  70  and stepped side walls  74  and  72 . 
         [0037]    Referring to  FIG. 6 , cap  62  is placed in a further open position, wherein first o-ring  64  is disengaged, and second o-ring  66  is now disengaged from side wall  70  and stepped side wall  76 . In this position, pressurized air from the upper section  53  of the reservoir  50  enters the bottom of the vent cap  62  and is allowed to bypass both the first o-ring  64  and the second o-ring  66  to enter the overflow port  82  for uninhibited release to the atmosphere. 
         [0038]    Referring now to  FIG. 7 , the cap  62  is placed into a third position, which is an open position. In this position, first o-ring  64 , second o-ring  66 , and third o-ring  68  are no longer engaging side walls  76 ,  74 , or  72  and all pressure would have been relieved before the third o-ring  68  is disengaged. 
         [0039]    Referring to  FIG. 8 , depicted is the cap  62 , with first o-ring  64 , second o-ring  66  and third o-ring  68  engaged between side wall  70  and stepped side walls  72 ,  74  and  76 . In this illustration, pressurized air coming into the port from the second chamber of the reservoir  78  is directed through the venting port  80  into a venting hose where it is placed in parallel with a pressure relief valve  84 , which allows release of pressure from the venting hose to the exhaust hose  86  at a pre-determined pressure, in this embodiment 5-20 psi. In addition, a check valve  88 , placed in parallel with the pressure relief valve  84 , prevents pressurized air directed through the venting hose to escape through the check valve in a single direction, forcing pressurized air to be released, if over 20 psi, through the pressure relief valve  84  to the exhaust hose  86 . In conditions where the engine is cooling off, the check valve allows air to re-enter the system through the exhaust line  86 , and back in through the venting hose  82 , passing through the check valve  88  without restriction. In a preferred embodiment, the pressure relief and check valve constitute a single valve placed in line with the venting hose. The pressure relief valve can be set at a predetermined relief pressure or be an adjustable valve wherein the pressure relief can be mechanically adjusted. 
         [0040]    Referring to  FIG. 9 , set forth is another embodiment having the cap  62  engaging o-ring seals  64 ,  66  and  68 . In this embodiment, the pressure relief valve  84 ′ is placed in parallel with check valve  88 ′ in line with the venting hose, which allows fluid from escaping through expansion half to an exhaust line  86 . In this embodiment, the use of a single valve is replaced with two independent valves; the exhaust of each is coupled together by a union  94 . 
         [0041]    Referring now to  FIG. 10 , set forth is an embodiment depicting the coolant reservoir  100 , an upper section  102 , a lower section  104 , and a vent neck  106 . In this embodiment, the vent trough  108  extends from an upper portion  109  of the upper section  102 , to the lower section  104 . A second trough  110  extends from the lower section  104  and, unlike the previous embodiment, the trough  110  is discontinued at vent port  112  so as not to extend to the vent neck  106 . In this embodiment, pressure relief and check valve  114  is secured to the vent port  112 . 
         [0042]    Referring now to  FIG. 11 , cap  116  having a first o-ring seal  118  and a second o-ring seal  120  is depicted. The first seal provides a seal between side wall  122  and step wall  124 . The second o-ring seal  120  provides a seal between side wall  126  and step wall  128 . When the cap is closed, no air is directed to the cap section and, as shown in  FIG. 10 , air is vented through the pressure relief/check valve  114  should any excess pressure above 20 psi expand from the lower section  104 . 
         [0043]    Referring to  FIG. 12 , set forth is an illustration with the cap  116  in a first position wherein first o-ring seal  118  no longer engages side wall  124  and pressurized air from the top of the reservoir can enter the cap area through the opening  130  and escape through relief port  132 . The second o-ring seal  120  remains engaged with side wall  126  and step wall  128 . 
         [0044]    Referring to  FIG. 13 , the cap  116  is placed in a position so that first o-ring  118  and second o-ring seal  120  no longer engage step side walls  128  or  124 . In this position all pressure has been relieved before the second o-ring  120  disengages. 
         [0045]    Referring to  FIGS. 14-18 , set forth an another embodiment wherein the pressure relief valve and check valve are formed integral with a cap.  FIG. 14  depicts the vent neck  152 , wherein pressurized air from the fluid overflow second chamber  151  of the reservoir  150  is directed through the trough  178  passing between the first o-ring  164  and second o-ring  166  with relief valve  184  preventing release of a pressure beneath 20 psi or the like predetermined pressure. While the preferred embodiment is to employ a predetermined pressure relief valve, the 20 psi valve is simply for illustration purposes only. The pressure can be any predetermined value and, as may also consist of a mechanism to allow for adjustment of the pressure relief valve. The cap  162  in this embodiment is a three o-ring design, having a first o-ring  164 , a second o-ring  166  and third o-ring  168 . When the cap is closed, as illustrated, the o-rings  164 ,  166  and  168  seal between the cap surface and stepped side walls  172 ,  174  and  176 . Pressurized air that enters the vent neck  152  from the second chamber  151  into the trough  178  would trapped by the pressure relief valve  182 . Check valve  186  prevents pressurized fluid from escaping through the check valve with no restriction for air to be drawn back into the reservoir. Referring to  FIG. 15 , cap  162  is illustrated being subjected to pressure exceeding 20 psi, or any pressure of design, wherein excess pressure is expelled through vent port  180  positioned between the first o-ring  164  and the third o-ring  168 . 
         [0046]    Referring to  FIG. 16 , cap  162  has been rotated to a position where the first o-ring  164  disengages stepped side wall  174 , wherein pressurized air from the lower section  151  of the reservoir  150  is allowed to vent through the trough  178  to the vent port  180  uninhibited, thereby releasing air pressure from inside the reservoir to the atmosphere. It is noted that the second o-ring  166  and third o-ring  168  remain engaged between side wall  170  and stepped side walls  174  and  172 . 
         [0047]    Referring to  FIG. 17 , cap  162  is placed in a further open position, wherein first o-ring  164  is disengaged, and second o-ring  166  is also disengaged from side wall  170  and stepped side wall  176 . In this position, pressurized air from the upper section  153  of the reservoir  150  enters the bottom of the vent cap  173  and is allowed to bypass both the first o-ring  164  and the second o-ring  166  to enter the vent port  180  for uninhibited release to the atmosphere. 
         [0048]    Referring to  FIG. 18 , the cap  162  is placed into a third position, which is an open position. In this position, first o-ring  164 , second o-ring  166 , and third o-ring  168  are no longer engaging side walls  176 ,  174 , or  172  and all pressure would have been relieved before the third o-ring  168  is disengaged. 
         [0049]    It is to be understood that while a certain form of the invention is illustrated, it is not to be limited to the specific form or arrangement herein described and shown. It will be apparent to those skilled in the art that various changes may be made without departing from the scope of the invention and the invention is not to be considered limited to what is shown and described in the specification and any drawings/figures included herein. 
         [0050]    One skilled in the art will readily appreciate that the present invention is well adapted to carry out the objectives and obtain the ends and advantages mentioned, as well as those inherent therein. The embodiments, methods, procedures and techniques described herein are presently representative of the preferred embodiments, are intended to be exemplary and are not intended as limitations on the scope. Changes therein and other uses will occur to those skilled in the art which are encompassed within the spirit of the invention and are defined by the scope of the appended claims. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention which are obvious to those skilled in the art are intended to be within the scope of the following claims.