Abstract:
A thermal relief valve, comprising a housing having a channel, a first aperture, and a second aperture, wherein the first aperture and the second aperture are arranged symmetrically about a central axis, an actuator within the housing arranged about the axis, a first seal secured to the actuator, the first seal comprising a plurality of apertures, and having a first upwardly facing surface, and a second downwardly facing surface, a first spring arranged between the second surface of the first seal and the housing component, a second seal comprising a first upwardly facing surface and a second downwardly facing surface, the first surface of the second seal positioned on the second surface of the first seal and, a second spring arranged between the second surface of the second seal and the housing, wherein the first seal and the second seal are axially movable by the actuator along the central axis.

Description:
FIELD OF THE INVENTION 
     The invention relates generally to a thermal relief valve, and more specifically, to a thermal relief valve with both a pressure relief seal and a thermal relief seal arranged about a single, central axis. 
     BACKGROUND OF THE INVENTION 
     Thermal relief valves are used in various applications which involve transporting fluid from a transmission to a heat exchanger in an automobile. In most applications, it is beneficial to have the fluid warm so that it can flow easier through tubes and components. In order to warm the fluid in a timely manner, a thermal relief valve is used to bypass the heat exchanger until an optimal operating temperature can be reached. Once this optimal temperature is reached, the thermal relief valve then allows the fluid to flow through the heat exchanger instead of bypassing it. 
     Available space in an engine bay and underneath an automobile can be limited, so it is important that any additional components such as a thermal relief valve take up as little space as possible. Additionally, the efficiency an automobile achieves is related to the weight of the car, so a thermal relief valve should also be as lightweight as possible while still acting as a bypass to the heat exchanger. 
     Since a thermal relief valve forces fluid to bypass a heat exchanger, the thermal relief valve must have a pressure release in order to prevent a blockage of the fluid. Since the fluid is responsible for the cooling of major components, such as the transmission, a blockage in the thermal relief valve would prevent any fluid from reaching the heat exchanger and would cause components to overheat while in operation causing extensive damage to the automobile. 
     A possible solution to this problem is disclosed in United States Patent Application Publication No. U.S. 2011/0061744 (Zillig et al.). Zillig et al. disclose a cooler bypass valve apparatus installed between a heat exchanger and conduits coupled to a device carrying fluid that needs to be cooled such as a radiator and transmission. A housing includes an inlet port and first and second outlet ports. At least one thermal actuator and at least one valve are mounted in a fluid flow passageway in the housing and actuate in response to the temperature of the fluid flowing within the apparatus. One valve that is arranged between an opened and closed position allows fluid to flow from the inlet port through the first and second outlet ports between a heat exchanger bypass loop and a heat exchanger cooling loop. In order to bypass the heat exchanger, sufficient pressure must be present within the system. Additionally, there are two thermal actuators which are arranged between the first and second outlets and actuate between opened and closed positions enabling fluid to only flow from the inlet port and through both the first and second outlet ports separately or in combination. Unfortunately, Zillig et al. fail to disclose an apparatus which bypasses the heat exchanger without any regard for the pressure within the system and also bypasses the heat exchanger completely instead of regulating the amount of fluid passing through the apparatus. Additionally, Zillig et al. fail to disclose an apparatus which includes a means for pressure relief which is axially arranged within the apparatus. 
     Another possible solution to this problem is disclosed in U.S. Pat. No. 8,141,790 (Sheppard). Sheppard discloses a bypass valve for a heat exchanger which allows fluid to flow through the heat exchanger at a certain operating temperature. A thermally sensitive actuator is mounted in the apparatus and can extend or retract depending on the temperature of the fluid flowing around the actuator. Once an optimal operating temperature has been reached, a bypass valve seat is arranged in a housing along with a bypass valve member which is movable by the actuator into an opened or closed position forcing the fluid to travel through the heat exchanger. A relief valve is mounted in the apparatus and has a relief valve member in order to close or open pressure relief ports. This relief valve member is biased towards the closed position to prevent excessive fluid from passing through the apparatus. Excessive pressure build up in the system would cause the relief valve member to move to an open position and allow fluid to flow through the apparatus. If the apparatus is not at an optimal operating temperature, the bypass valve member is not in a closed position which would allow fluid to flow freely through the apparatus without the need for the relief valve member. Unfortunately, Sheppard fails to disclose an apparatus which has the least amount of ports possible in order to save on weight and operating space. Additionally, Sheppard fails to disclose an apparatus which relieves the excessive pressure within the system while also guaranteeing fluid to flow through the heat exchanger and also fails to disclose a pressure relief means axially arranged within the apparatus. 
     Thus, there has been a long-felt need for a thermal relief valve that is both lightweight and compact while also comprising a pressure relief means axially arranged with a thermal relief means within the body of the apparatus. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention broadly comprises a thermal relief valve, comprising a housing having a channel, a first aperture, and a second aperture, wherein the first aperture and the second aperture are arranged symmetrically about a central axis, an actuator within the housing arranged about the axis, a first seal secured to the actuator, the first seal comprising a plurality of apertures, and having a first upwardly facing surface, and a second downwardly facing surface, a first spring arranged between the second surface of the first seal and the housing component, a second seal comprising a first upwardly facing surface and a second downwardly facing surface, the first surface of the second seal positioned on the second surface of the first seal and, a second spring arranged between the second surface of the second seal and the housing, wherein the first seal and the second seal are axially movable by the actuator along the central axis. 
     Additionally, the present invention comprises a seal assembly of a thermal relief valve, the thermal relief valve comprising a housing, an actuator within the housing, a first spring arranged within the housing, and a second spring arranged within the housing, the seal assembly comprising a first seal secured to the actuator, the first seal comprising a plurality of apertures, and having a first upwardly facing surface, and a second downwardly facing surface and, a second seal comprising a first upwardly facing surface and a second downwardly facing surface, the first surface of the second seal positioned on the second surface of the first seal, wherein the first spring biases the first seal along the second surface of the first seal and the second spring biases the second seal along the second surface of the second seal. 
     Additionally, the present invention comprises a thermal relief valve, comprising a housing having at least one channel, a first aperture, and a second aperture, wherein the first aperture and the second aperture are arranged symmetrically about a central axis, an actuator within the housing arranged about the central axis housing, a first seal secured to the actuator, the first seal comprising a plurality of apertures, and having a first upwardly facing surface, and a second downwardly facing surface, a first spring arranged between the second surface of the first seal and the housing component, a second seal comprising a first upwardly facing surface and a second downwardly facing surface, the first surface of the second seal positioned on the second surface of the first seal and, a second spring arranged between the second surface of the second seal and the housing, wherein when the thermal relief valve is in a first configuration the first surface of the first seal engages the housing and the first surface of the second seal engages the second surface of the first seal, when the thermal relief valve is in a second configuration the actuator is axially displaced, the first surface of the first seal does not engage the housing, and the first surface of the second seal engages the second surface of the first seal, and when the thermal relief valve is in a third configuration the first surface of the second seal does not engage with the second surface of the first seal. 
     A primary object of the invention is to provide a thermal relief valve which is compact, arranges all components on a central axis, and restricts fluid that is being transported to a heat exchanger in order to reach an optimal operating temperature while also having a pressure relief means and a thermal relief means. 
     These and other objects, features and advantages of the present invention will become readily apparent upon a review of the following detailed description of the invention, in view of the drawings and appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the invention taken with the accompanying figures, in which: 
         FIG. 1  is a top perspective view of thermal relief valve  10  of the present invention; 
         FIG. 2  is a bottom perspective view of thermal relief valve  10 ; 
         FIG. 3  is a top view of thermal relief valve  10 ; 
         FIG. 4  is a bottom view of thermal relief valve  10 ; 
         FIG. 5  is a side view of thermal relief valve  10 ; 
         FIG. 6  is a top perspective view of first housing component  12 ; 
         FIG. 7  is a bottom perspective view of first housing component  12 ; 
         FIG. 8  is a top perspective view of second housing component  14 ; 
         FIG. 9  is a bottom perspective view of second housing component  14 ; 
         FIG. 10  is a perspective view of thermal actuator  36  and thermal relief seal  25 ; 
         FIG. 11  is a cross-sectional view of thermal relief valve  10  in a first configuration taken generally along line  11 - 11  shown in  FIG. 5 ; 
         FIG. 12  is a cross-sectional view of thermal relief valve  10  in a second configuration taken generally along line  11 - 11  shown in  FIG. 5 ; and, 
         FIG. 13  is a cross-sectional view of thermal relief valve  10  in a third configuration taken generally along line  11 - 11  shown in  FIG. 5 ; 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the invention. It is to be understood that the invention as claimed is not limited to the disclosed aspects. 
     Furthermore, it is understood that this invention is not limited to the particular methodology, materials and modifications described and as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular aspects only, and is not intended to limit the scope of the present invention. 
     Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention pertains. It should be understood that any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the invention. The assembly of the present invention could be driven by hydraulics, electronics, and/or pneumatics. 
     Adverting now to the figures,  FIG. 1  is a top perspective view of thermal relief valve  10  of the present invention. Thermal relief valve  10  broadly comprises first housing component  12  and second housing component  14 . First housing component  12  comprises rim  13 , aperture  15 , guides  16   b,  and channels  16   a  which allow fluid (not shown) to flow into thermal relief valve  10 . Cylindrical enclosure  17  houses pin  34  (shown in  FIG. 11 ) and is integral to first housing component  12 . Rim  13  is integral with first housing component  12  and secures second housing component  14  to first housing component  12 . In a preferred embodiment, rim  13  has a larger radius than first housing component  12  and second housing component  14 . It should be appreciated, however, that the use of different radii is possible and considered to be within the scope of the invention as claimed. For example, first housing component  12  could have a larger radius than rim  13 . First housing component  12  is secured to second housing component  14  along surface  14   b  and surface  13   a  via a press fit (shown in  FIG. 11 ). Other securement means are possible such as screwing first housing component  12  and second housing component  14  together or using a permanent seal such as epoxy or welding. Additionally, first housing component  12  and second housing component  14  could be manufactured as a single component. If first housing component  12  and second housing component  14  were integral with one another, internal components such as thermal relief seal  10 , pressure relief seal  30 , thermal actuator  36 , seal assembly  23 , spring  22 , and spring  24  could be arranged within the housing by an externally threaded screw plate engaged with internal threads on the housing (not shown) or the housing could be formed to secure all the components within the housing. 
       FIG. 2  is a bottom perspective view of thermal relief valve  10 . Second housing component  14  is concentrically arranged within rim  13  of first housing component  12 . Apertures  18  are arranged in a symmetrical pattern centered on central axis  40  (shown in  FIG. 11 ) of thermal relief valve  10  on the bottom of second housing component  14 . Recess  19  is arranged in the center of second housing component  14  and secures spring  22  and spring  24  within first housing component  12  and second housing component  14  (shown in  FIG. 11 ). In a preferred embodiment, first housing component  12  and second housing component  14  are manufactured from nylon. It should be appreciated, however, that the use of different materials is possible and considered to be within the scope of the invention as claimed. For example, first housing component  12  and second housing component  14  could be manufactured from a durable but lightweight material such as aluminum. 
       FIG. 3 ,  FIG. 4 , and  FIG. 5  are a top view, bottom view, and side view of thermal relief valve  10 , respectively. As shown in the figures, channels  16   a  and guides  16   b  are arranged in a symmetrical pattern about cylindrical enclosure  17 . Guides  16   b  guide thermal actuator  36  (shown in  FIG. 11 ) during linear displacement of thermal relief seal  25 . Channels  26   a  are integral with first housing component  12  and allow fluid (not shown) to flow through thermal relief valve  10  when thermal relief seal  25  is not linearly displaced by thermal actuator  36  (shown in  FIG. 11 ). 
       FIG. 6  and  FIG. 7  are a top perspective view and bottom perspective view of first housing component  12 , respectively. As shown in the figures, channels  26   a  are arranged symmetrically about central axis  40  (shown in  FIG. 11 ). It is important to note that channels  26   a  extend radially outward greater than the radial distance of thermal relief seal  25 . When thermal actuator  36  is not thermally expanded linearly, upwardly facing surface  25   a  of thermal relief seal  25  engages surface  12   a  of first housing component  12  (shown in  FIG. 11 ). When thermal relief seal  25  is not linearly displaced and engaged with surface  12   a  of first housing component  12 , fluid can only pass through thermal relief valve  10  via channels  26   a  unless there is excessive pressure build up. In the case of excessive pressure build up, fluid could flow through pressure relief apertures  26   b  of thermal relief seal  25  (shown in  FIG. 10 ). Additionally, guides  16   b  extend linearly within first housing component  12  to guide thermal actuator  36 . In a preferred embodiment, channels  26   a  are arranged symmetrically within first housing component  12 . It should be appreciated, however, that the use of different arrangements and positions of channels  26   a  is possible and considered to be within the scope of the present invention as claimed. For example, channels  26   a  could be channels or apertures arranged on thermal relief seal  25  (shown in  FIG. 10 ) to allow fluid to flow through thermal relief valve  10  when thermal relief seal  25  is not linearly displaced. 
       FIG. 8  and  FIG. 9  are top and bottom perspective view of second housing component  14 , respectively. Second housing component  14  comprises apertures  18 , recess  19 , and supports  27 . Recess  19  is axially arranged on second housing component  14  and engages spring  22  and spring  24  along surface  19   a  (shown in  FIG. 11 ). Supports  27  are symmetrically arranged on surface  14   a  of second housing component  14 . Supports  27  reinforce second housing component  14  when spring  22  and spring  24  engage recess  19  (shown in  FIG. 11 ). In a preferred embodiment, apertures  18  are symmetrically arranged about recess  19 . It should be appreciated, however, that the use of different arrangements are possible and considered to be within the scope of the present invention as claimed. For example, apertures  18  could be combined into a single aperture positioned within recess  19  to allow fluid to pass through thermal relief valve  10  or apertures  18  could be asymmetrical. Both recess  19  and supports  27  are integral with second housing component  14 . 
       FIG. 10  is a perspective view of thermal actuator  36  and thermal relief seal  25 . Thermal actuator  36  broadly comprises pin  34  and body  32 . Pin  34  is concentrically arranged within body  32  and can be linear displaced within body  32 . Additionally, thermal relief seal  25  is secured to surface  32   a  of body  32 . Thermal relief seal  32  can be integral with body  32  or permanently secured via a press fit or epoxy. Arranged within thermal actuator  36  is an expandable medium (not shown). In a preferred embodiment, the expandable medium is a wax element which melts when thermal actuator  36  reaches a specific operating temperature. It should be appreciated, however, that the use of different expandable mediums is possible and should be considered within the scope of the invention as claimed. Surface  36   a  of thermal actuator  36  engages surface  12   a  of first housing component  12  and surface  34   a  of pin  34  engages surface  17   a  of cylindrical enclosure  17  (shown in  FIG. 11 ). Pressure relief apertures  26   b  are symmetrically arranged about body  32  of thermal actuator  36 . In a preferred embodiment, thermal relief seal  25  and pressure relief seal  30  are washers axially arranged on body  32  of thermal actuator  36 . Other types and shapes of seals can be used depending on the operating constraints. 
       FIG. 11  is a cross-sectional view of thermal relief valve  10  in a first configuration taken generally along line  11 - 11  shown in  FIG. 5 . As shown in the figure, thermal actuator  36 , seal assembly  23 , spring  22 , and spring  24  are axially arranged about centerline  40 . Seal assembly  23  comprises thermal relief seal  25  and pressure relief seal  30 . Thermal relief seal  25  is held in place against surface  12   a  of first housing component  12  by spring  22  and directs fluid through channels  26   a.  Additionally, pressure relief seal  30  is axially arranged about body  32  of thermal actuator  36  and held in place against downwardly facing surface  25   b  of pressure relief seal  25  by spring  24 . Spring  22  engages downwardly facing surface  25   b  of thermal relief seal  25  and surface  14   a  of second housing component  14 . Spring  24  engages downwardly facing surface  30   b  of pressure relief seal  30  and surface  19   a  of recess  19 . Spring  22  and spring  24  provide resistance to fluid (not shown) flowing through thermal relief valve  10 . Since thermal relief seal  25  and pressure relief seal  30  have independent springs, both thermal relief seal  25  and pressure relief seal  30  can be linearly displaced independently of one another. In a preferred embodiment, spring  22  has a greater stiffness value than spring  24  since spring  22  is compressed by pin  34  linearly expanding and engaging surface  17   a  while spring  24  is compressed by the force the fluid (not shown) imparts on upwardly facing surface  30   a  of pressure relief seal  30 . It should be appreciated, however, that the use of different stiffness values for spring  22  and spring  24  is possible and considered to be within the scope of the invention as claimed. 
       FIG. 12  is a cross-sectional view of thermal relief valve  10  in a second configuration taken generally along line  11 - 11  shown in  FIG. 5 . As the temperature of fluid (not shown) flowing though thermal relief valve  10  increases, the expandable medium (not shown) will expand, forcing pin  34  to be linearly displaced along centerline  40  and to engage surface  17   a  of cylindrical enclosure  17  via surface  34   a.  When pin  34  is linearly displaced, thermal relief seal  25  and pressure relief seal  30  are also linearly displaced causing upwardly facing surface  25   a  of thermal relief seal  25  to separate from surface  12   a  of first housing component  12  allowing fluid (not shown) to flow though thermal relief seal  10  at a greater volumetric flow rate. It is important to note that upwardly facing surface  30   a  of pressure relief seal  30  remains engaged with downwardly facing surface  25   b  of thermal relief seal  25  when thermal actuator  32  axially displaces thermal relief seal  25  and thermal relief seal  30 . 
       FIG. 13  is a cross-sectional view of thermal relief valve  10  in a third configuration taken generally along line  11 - 11  shown in  FIG. 5 . Pressure relief apertures  26   b  allow fluid (not shown) to apply pressure to pressure relief seal  30  if there is a pressure build-up in the system. If the pressure applied to pressure relief seal  30  through pressure relief apertures  26   b  reaches a certain amount, upwardly facing surface  30   a  of pressure relief seal  30  would separate from downwardly facing surface  25   b  of thermal relief seal  25  and allow fluid to flow through thermal relief valve  10  at a greater volumetric flow rate. It is important to note that thermal relief seal  25  can be axially displaced any length along centerline  40  when pressure relief seal  30  is forced open due to pressure from the fluid (not shown) since thermal relief seal  25  is axially displaced as a function of temperature while pressure relief seal  30  is axially displaced as a function of temperature due to downwardly facing surface  25   b  of thermal relief seal  25  engaging with upwardly facing surface  30   a  and a function of pressure being applied to upwardly facing surface  30   a  of pressure relief seal  30 . 
     it will be appreciated that various aspects of the above-disclosed invention and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. 
     LIST OF REFERENCE NUMERALS 
     
         
           10  thermal relief valve 
           12  first housing component 
           13  cap 
           13   a  surface 
           14  second housing component 
           14   a  surface 
           14   b  surface 
           15  aperture 
           16   a  channel 
           16   b  guides 
           17  cylindrical enclosure 
           17   a  surface 
           18  apertures 
           19  channel 
           19   a  surface 
           22  spring 
           23  seal assembly 
           24  spring 
           25  thermal relief seal 
           25   a  upwardly facing surface 
           25   b  downwardly facing surface 
           26   a  channels 
           26   b  apertures 
           27  support 
           30  pressure relief seal 
           30   a  upwardly facing surface 
           30   b  downwardly facing surface 
           32  body 
           32   a  surface 
           34  pin 
           34   a  surface 
           36  thermal actuator 
           36   a  surface 
           40  centerline