Patent Publication Number: US-11041429-B2

Title: Cooling jacket for exhaust valve and thermostat and cooling bottle

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/723,909 filed on Oct. 3, 2017. The entire disclosure(s) of (each of) the above application(s) is (are) incorporated herein by reference. 
    
    
     FIELD 
     The present disclosure relates to a vehicle and, more particularly, to an apparatus and method for cooling an engine of a vehicle. 
     BACKGROUND 
     This section provides background information related to the present disclosure which is not necessarily prior art. 
     Vehicles such as snowmobiles utilize two stroke engines which are run at high RPM. These two stroke engines produce a significant amount of heat which builds up in the head, cylinder and exhaust ports of the engine structure that needs to be removed from the engine. Traditionally, these two cycle engines use cooling fluid that utilizes a bypass check valve incorporated into the engine crank case to direct the cooling fluid to different heat exchange structures as is needed depending on the temperature of the cooling fluid. 
     These two stroke engines also produce a significant amount vibration in addition to the extreme temperatures which significantly reduce the life of components such as the engine&#39;s fuel system including injectors, the pistons, intake manifolds, and exhaust systems, a cooling system bypass check valve. It is an intention of the present teachings to improve heat management within an engine to improve the life expectancy of engine components. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. The present disclosure teaches an improved system and method for reliably managing two cycle engine heat, and particularly two cycle engine heat snowmobile. The system moves the cooling system bypass check valve out of the engine and into a location in a cooling system which is subjected to significantly lower vibrational energy. 
     According to the present teachings, presented is coolant reservoir configured to be placed within a vehicle cooling system. The coolant reservoir has a bottle that defines a first chamber and a second chamber fluidly coupled to the first chamber through an aperture having a valve seat. The first chamber is fluidly coupled to a source of heated engine cooling fluid, while the second chamber is fluidly coupled to an engine water pump. A thermally responsive actuator having a sliding member and a valve seat engaging surface is disposed within the first chamber. The sliding member is movable from a first open position to a second closed position when the coolant is above a first temperature. 
     According to the afore mentioned paragraph and the following paragraphs, a first spring can be engaged between the sliding member and the coolant bottle and is operative to urge the sliding member in a first direction relative to the valve seat. A second spring can be engaged between the sliding member and the coolant bottle and operative to urge the valve seal in a second direction relative to the valve seat. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have a first member defining a first portion of the first chamber and a first portion of the second chamber. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have a second member defining a second portion of the first chamber, and wherein the thermally responsive actuator has a flange member couple to the second member. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have a first member defines a first portion of the first chamber and a first portion of the second chamber. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have a first member defining a first chamber first aperture fluidly coupled to the engine water pump. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have a first member defining a first chamber first aperture fluidly coupled to the source of heated engine cooling fluid. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have first member defining a bypass aperture between the first and second chambers having the valve seat, whereby the valve seat engaging surface is positioned adjacent the bypass aperture. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir can have the thermally responsive actuator axially coupled to the bottle. 
     According to the afore mentioned paragraphs and the following paragraphs, the coolant reservoir first member defines a first chamber second aperture fluidly coupled to a cooling chamber. 
     According to the afore mentioned paragraphs and the second member defines a first chamber second aperture fluidly coupled to the cooling chamber. 
     According to the present teachings, and the previously mentioned and following paragraphs, presented is coolant reservoir configured to be placed within a vehicle cooling system. A coolant bottle formed of at least first and second members. The first and second members define a first chamber, and the first member further forms a portion of a second chamber. The first and second chambers are fluidly coupled through an aperture having a valve seat. The first chamber is fluidly coupled to a source of heated engine cooling fluid, and the second chamber is fluidly coupled to an engine water pump. The bottle has a thermally responsive actuator disposed within the first chamber that has a sliding member having a valve seat engaging surface. The sliding member is movable from a first open position when the coolant is below a first temperature to a second position when the coolant is above the a first temperature. 
     According to the present teachings, and the previously mentioned and following paragraphs wherein the first member defines a second chamber first aperture fluidly coupled to the engine water pump. 
     According to the present teachings, and the previously mentioned and following paragraphs wherein the first member further defines a second chamber first aperture fluidly coupled to the source of heated engine cooling fluid. 
     According to the present teachings, and the previously mentioned and following paragraphs wherein the first member defines a second chamber second aperture fluidly coupled to a heat exchange chamber. 
     According to the present teachings, and the previously mentioned and following paragraphs wherein the second member defines a first chamber second aperture fluidly coupled to the heat exchange chamber. 
     According to the present teachings, and the previously mentioned and following paragraphs further comprising a third member defining a closable third coolant accepting aperture. 
     According to the present teachings, and the previously mentioned and following paragraphs further having a conical swirl plate member disposed between the third chamber and second chamber, the conical swirl plate member defines a plurality of coupling apertures fluidly coupling the second and third chambers. 
     According to the present teachings, and the previously mentioned and following paragraphs where the sliding valve element has a second exterior bearing surface which is configured to engage a first end of the second intermediate spring. 
     According to the present teachings, and the previously mentioned and following paragraphs wherein the sliding valve element bearing surface slidably supports the valve seal and regulates the movement of the valve seal toward and away from the valve seat. 
     According to the present teachings, and the previously mentioned and following paragraphs wherein the thermally responsive actuator includes a retractable piston, the thermally responsive actuator is configured to retract the piston and thereby position the sliding valve element in an open position. 
     According to the present teachings, and the previously mentioned and following paragraphs where the thermally responsive actuator includes a retractable piston, the thermally responsive actuator is configured to retract the piston and thereby position a valve seal stop on the sliding valve element in an open position. 
     According to the present teachings, and the previously mentioned and following paragraphs, presented is coolant reservoir configured to be placed within a vehicle cooling system. The coolant reservoir has a first member defining first and second chambers and a first bypass passage having a first valve seat there between. The first chamber is fluidly coupled to a heated engine fluid supply and the second chamber is fluidly coupled to an engine fluid return. The bottle includes a thermally responsive actuator that moves a valve bearing element between an open and closed positions. The thermally responsive actuator includes a sliding valve element disposed within the first chamber and a valve seal which is configured to engage the first valve seat. The sliding valve element has a second exterior bearing surface which is configured to fixably engage the first member. The thermally responsive actuator is operably engaged between the sliding valve element and the bottle and operative to urge the sliding valve element away the valve seat and wherein the second spring is engaged between the sliding valve element and the valve seal and operative to urge the valve seal toward the valve seat. 
     According to the present teachings, and the previously mentioned and following paragraphs where the first member defines a second chamber first aperture fluidly coupled to the engine water pump. 
     According to the present teachings, and the previously mentioned and following paragraphs where the first member further defines a second chamber first aperture fluidly coupled to the source of heated engine cooling fluid. 
     According to the present teachings, and the previously mentioned and following paragraphs where the first member defines a second chamber second aperture fluidly coupled to a heat exchange chamber. 
     According to the present teachings, and the previously mentioned and following paragraphs where the second member defines a first chamber second aperture fluidly coupled to the heat exchange chamber. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1  is a perspective view of a snowmobile. 
         FIGS. 2A and 2  B are exploded views of the snowmobile of  FIG. 1 . 
         FIGS. 3A and 3B  are opposite side views of the engine of  FIG. 2 . 
         FIG. 4  is an exploded view of the engine of  FIG. 3 . 
         FIG. 5  is a block diagrammatic view of a cooling system for a vehicle. 
         FIG. 6  is a view of a coolant reservoir bottle configured to be placed within a vehicle cooling system in  FIG. 5 . 
         FIGS. 7A and 7B  are cross sectional views of a coolant reservoir configured to be placed within the vehicle cooling system shown in  FIG. 5  with a valve elements in opened and closed positions respectfully. 
         FIGS. 8A and 8B  are perspective views of a thermally activated valve according to the present teachings. 
         FIG. 9  is a perspective view of an engine having improved cooling fluid flow according to the present teachings. 
         FIGS. 10A and 10B  represent front and rear views of the flow of cooling fluid through an engine according to the present teachings. 
         FIG. 10C  represents a sectional view of the crankcase through the exhaust port valves. 
         FIG. 11  is a side cross sectional view of the engine show in  FIG. 9 . 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. Although the following description includes several examples of a snowmobile application, it is understood that the features herein may be applied to any appropriate vehicle, such as, all-terrain vehicles, utility vehicles, moped and scooters. The examples disclosed below are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed in the following detailed description. Rather, the examples are chosen and described so that others skilled in the art may utilize their teachings. 
     Referring now to  FIGS. 1-2B  one embodiment of an exemplary snowmobile  10  is shown. Snowmobile  10  includes a chassis  12 , an endless belt assembly  14 , and a pair of front skis  20 . Snowmobile  10  also includes a front-end  16  and a rear-end  18 . 
     The snowmobile  10  also includes a seat assembly  22  that is coupled to the chassis assembly  12 . A front suspension assembly  24  is also coupled to the chassis assembly  12 . The front suspension assembly  24  may include a steering wheel  26 , shock absorbers  28  and the skis  20 . A rear suspension assembly  30  is also coupled to the chassis assembly  12 . The rear suspension assembly  30  may be used to support the endless belt  14  for propelling the vehicle. An electrical console assembly  34  is also coupled to the chassis assembly  12 . The electrical console assembly  34  may include various components for electrically controlling the snowmobile  10 . 
     The snowmobile  10  also includes an engine assembly  40 . The engine assembly  40  is coupled to an intake assembly  42  and an exhaust assembly  44 . The intake assembly  42  is used for providing fuel and air into the engine assembly  40  for the combustion process. Exhaust gas leaves the engine assembly  40  through the exhaust assembly  44 . An oil tank assembly  46  is used for providing oil to the engine for lubrication and for mixing with the fuel in the intake assembly  42 . A drivetrain assembly  48  is used for converting the rotating crankshaft assembly from the engine assembly  40  into a force to use the endless belt  14  and thus the snowmobile  10 . The engine assembly  40  is also coupled to a cooling assembly  50 . 
     The chassis assembly  12  may also include a bumper assembly  60 , a hood assembly  62  and a nose pan assembly  64 . The hood assembly  62  is movable to allow access to the engine assembly  40  and its associated components. 
     Referring now to  FIGS. 3A, 3B and 4 , the engine assembly  40  is illustrated in further detail. The engine assembly  40  is a two-stroke engine that includes the exhaust assembly  44  which may be referred to as an exhaust manifold. 
     The engine assembly  40  may include spark plugs  70  which are coupled to a cylinder head cover  72 . The cylinder head cover  72  is coupled to the cylinder head  74  which is used for housing the pistons  76  to form a combustion chamber  78  therein. The cylinder head  74  is mounted to the engine block  80 . 
     The fuel system  82  includes fuel lines  84  and fuel injectors  86 . The fuel lines  84  provide fuel to the fuel injectors  86  which inject fuel, in this case, into a port adjacent to the pistons  76 . An intake manifold  88  is coupled to the engine block  80 . The intake manifold  88  is in fluidic communication with the throttle body  90 . Air is air for the combustion processes admitted into the engine through the throttle body  90  which may be controlled directly through the use of an accelerator pedal or hand operated switch. A throttle position sensor  92  is coupled to the throttle to provide a throttle position signal corresponding to the position of a throttle valve of throttle plate  94  to an engine controller. 
     The engine block  80  is coupled to crankcase  100  and forms a cavity for housing the crankshaft  102 . The crankshaft  102  has connecting rods  104  which are ultimately coupled to the pistons  76 . The movement of the pistons  76  within the engine chamber  78  causes a rotational movement at the crankshaft  102  by way of the connecting rods  104 . The crankcase may have openings or vents  106  therethrough. The system is lubricated using oil lines  108  which are coupled to the oil injectors  110  and an oil pump  112 . 
     The crankshaft  102  is coupled to the flywheel  118  and having a stator  120  therein. The flywheel  118  has crankshaft position sensors  122  that aid in determining the positioning of the crankshaft  102 . The crankshaft position sensors  122  are aligned with the teeth  124  and are used when starting the engine as well as being used to time the operation of the injection of fuel during the combustion process. A stator cover  126  covers the stator  120  and flywheel  118 . 
       FIG. 5  is a block diagrammatic view of a cooling system for a vehicle. As described further below, the engine assembly  40  is water cooled, having a water pump  49  configured to push coolant fluid into the engine block  80  and through the engine assembly  40 . The heated coolant fluid leaves a source of heated engine cooling fluid  211  in the engine assembly  40 , which in this case originates from the cylinder head  74  of the engine assembly  40 , and travels to a coolant reservoir  200 . The coolant reservoir  200  has a bottle  202  configured to be placed within the vehicle cooling system. The bottle  202  defines first and second chambers  204  and  206  which are fluidly coupled together through an aperture  207 . Defined about the aperture  207  is a valve seat  208 . The first chamber  204  is fluidly coupled to the source of heated engine cooling fluid  211 , while the second chamber  206  is fluidly coupled to the engine water pump  49  which returns the coolant fluid back to the engine assembly  40 . 
     Upon exposure to heated fluid from the source of heated engine cooling fluid  211 , a thermally responsive actuator  212  closes the aperture  207  between the first and second chambers  204  and  206 , inducing the heated fluid from the engine assembly  40  to pass from the first chamber  204 , through a first chamber exit port  222  to a heat exchange chamber  262 . The heat exchanger  262  is configured to be cooled by moving snow that removes heat from the cooling fluid. This heat reduced cooling fluid is then returned to the second chamber  206  through an inlet port  226  where bubbles are allowed to escape into the third chamber  205 . The fluid is then transferred from the second chamber  206  through a second chamber exit port  228  to a hose  230  coupled to the water pump  49 . 
       FIG. 6  is an exterior view of the bottle  202  within the vehicle cooling system shown in  FIG. 5  with an interior valve element (not shown). The bottle  202  is formed of first, second, and third exterior members ( 232 ,  234 ,  236 ) which define the first, second and third chambers  204 ,  206 ,  205 . The first and second members  232  and  234  define the first chamber  204 , and the first member  232  further forms a portion of a second chamber  206 . The third chamber  205  which is fluidly coupled to the second chamber  234  is formed of the third funnel shaped exterior member  236 , which has a closable filling port  242  that allows the filling of the cooling system with coolant as needed. The first chamber  204  is fluidly coupled to the source of heated engine cooling fluid  211 , and the second chamber is fluidly coupled to the engine water pump  49  as described above. 
     As shown in  FIGS. 7A and 7B , the bottle  202  has a thermally responsive actuator  212  disposed within the first chamber  204 , and configured to move a thermally actuated sliding valve element  210  having the valve seat engaging surface or seal  208 . The thermally actuated sliding member  210  is movable from a first open position where the valve seal  209  engages the valve seat  208  that is displaced from the valve seat  208  to a second position when the coolant is below a first temperature. 
     As shown in  FIG. 7A , when functioning, such as during vehicle startup, the thermally responsive actuator  212  is in an open position within the first chamber  204 . Fluid from the heated engine fluid supply  211  flows in to the first chamber  204 , past the thermally responsive actuator  212 , and valve seat  208  through the aperture  207  and into the second chamber  206 . The fluid then is returned directly to the water pump  49 . The sliding valve element  210  has a second exterior bearing flange  252  which is configured to engage the first member  232  to fixably couple the element to the bottle  202 . At temperatures below a first predetermined temperature cooling fluid is allowed to circulate directly into the engine at startup. 
       FIG. 7B  is a cross sectional view of the bottle  202  with the thermally responsive actuator  212  in a closed position. When subjected to heated engine fluid, the thermally responsive actuator  212  thermal element  256  expands and thus translates the sliding valve element  210  and associated seal member  209  into engagement with the valve seat  208 . This closes the aperture  207  between the first and second chambers  204  and  206  which directs the heated fluid through the heat exchange chamber  262 . 
     The bottle  202  first member  232  defines the first chamber first aperture  258  fluidly coupled to a source of heated engine cooling fluid  211  (in this case the cylinder head  74 ). The second member  234  defines a first chamber second aperture  260  fluidly coupled to a cooling chamber  262 . The coolant reservoir first member  232  defines the second chamber second aperture  256  fluidly coupled to the cooling chamber  262  configured to receive cooled fluid from the cooling chamber  262 . 
     Disposed between the second and third chambers  206  and  205  is a conical swirl plate member  264 . The conical swirl plate member  264  defines a plurality of coupling apertures  266  fluidly coupling the second and third chambers  206  and  205 . These apertures  266  are configured to allow trapped gasses within the cooling system to escape from the second chamber  206  into the third chamber  205  as well as to allow coolant poured into the third chamber  205  through the closable filling port  242  to flow down into the second and third chambers  204  and  206  where it is incorporated into the cooling system. 
       FIGS. 8A and 8B  is a perspective view of the thermally responsive actuator  212  according to the present teachings. The thermally responsive actuator  212  is configured to retract the piston  270  and thereby position the valve seal member  209  away from the valve seat  208  when the thermally responsive actuator  212  is exposed to fluid temperatures below a predetermined value, in an open position (see  FIG. 7A  above). The first and second springs  214  and  216  function to pull the thermally responsive actuator  212  way from the valve seat  208 , when the piston  270  is retracted. Similarly, the thermally responsive actuator  212  is configured to expel the piston  270  and thereby position the valve seal member  209  on the valve seat  208  when the thermally responsive actuator  212  is exposed to fluid temperatures above a predetermined value, in a closed position (see  FIG. 7B  above). The sliding valve element  210  bearing surface slidably supports the valve seal member  209  and regulates the movement of the valve seal member  209  toward and away from the valve seat  208 . 
       FIG. 9  is a perspective view of the engine  40  having improved cooling fluid flow according to the present teachings.  FIGS. 10A and 10B  represent front and rear views of the flow of cooling fluid through the engine shown in  FIG. 9 .  FIG. 10C  represents a sectional view of the crank case through the exhaust valves. As can be seen, the cooling routes surround the oval aperture of the exhaust valve inlet to take excess heat way from this very susceptible component. These represent flow areas  254  as shown in  FIG. 10A . 
       FIG. 11  is a cross sectional view of engine showing the cooling apertures within the engine shown in  FIG. 9 . With reference to these figures, the engine assembly  40 , having the engine block  80  and cylinder head  74 , define interior cooling chambers  250  which accept flowing cooling fluid. The velocity of the fluid at the entrance into the engine is greater than 2.1 m/s and preferably between 2.1 and 3.0 m/s. Fluid velocities for a second series of passages  254  annularly disposed about the exhaust port  256  are most preferably greater than 2.4 m/s and preferable remain between 2.1 and 3 m/s. Temperatures for the cooled regions can be between 275 degrees F. and 350 degrees F. 
     As shown, cooling fluid from the bottle  202  passes through the water pump  49  and into a first portion of the engine block at  252 . As this high velocity cooled fluid enters the engine block  80 , a first portion of the flow passes directly into the second series of passages  254  annularly disposed about the exhaust port  256  which is coupled to the exhaust assembly  44 . After cooling the engine components adjacent to the exhaust portion  256  this portion of the fluid flows into the cylinder head  74 . A second portion  258  of the flow passes directly into a third series of passages  260  annularly disposed about the cylinders and pistons  76 . After cooling the engine components adjacent to the cylinders this portion of the fluid flows into the cylinder head  74  and combines with the first portion of the fluid flow. This heated combined fluid flow exits the cylinder head  74 , and becomes the source of heated engine cooling fluid  211 . 
     Examples are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of examples of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that examples may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some examples, well-known processes, well-known device structures, and well-known technologies are not described in detail. 
     The foregoing description has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular example are generally not limited to that particular example, but, where applicable, are interchangeable and can be used in a selected example, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.