Abstract:
An engine system with a coolant control valve includes: a valve housing having a first valve space and a second valve space formed at both sides by a partition and including a connection passage formed in the partition; a first rotary valve disposed in the first valve space and having first coolant passages; a second rotary valve disposed in the second valve space and having second coolant passages; distribution lines respectively connected to positions corresponding to the first coolant passages and the second coolant passages and distributing the coolant coming through the first rotary valve and the second rotary valve; and a driver to rotate the first rotary valve and the second rotary valve. In particular, the first and second coolant passages are connected to the connection passage depending on the rotation positions of the first rotary valve and the second rotary valve.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2015-0161802, filed on Nov. 18, 2015, the entire contents of which are incorporated herein by reference. 
       FIELD 
       [0002]    The present disclosure relates to an engine system having a coolant control valve to improve an entire cooling efficiency and a fuel consumption. 
       BACKGROUND 
       [0003]    The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
         [0004]    Engines produce torque by burning a fuel to create engine, and discharge surplus thermal energy. Particularly, a coolant absorbs thermal energy as it circulates through an engine, a heater, and a radiator, and releases the thermal energy. 
         [0005]    Oil becomes highly viscous at low engine coolant temperatures. With thick oil, friction and fuel consumption increase, and exhaust gas temperatures rise gradually, lengthening the time taken for catalyst activation and causing deterioration in exhaust gas quality. Moreover, it takes a long time to get a heater to function normally, so passengers and a driver will feel cold. 
         [0006]    When the engine coolant temperature is excessively high, knocking may occur. If ignition timing is adjusted to suppress knocking, the engine performance may be degraded. In addition, excessive lubricant temperatures may result in poor lubrication. 
         [0007]    However, one coolant control valve is used in specific regions of an engine, and is a valve that controls a number of cooling elements, like keeping the coolant at high temperatures and other regions at low temperatures. 
         [0008]    On the other hand, the coolant of the cylinder block of the relatively low temperature is supplied to the oil cooler and the EGR cooler in a warm condition of the temperature of the coolant such that the fuel consumption may be increased due to the decreasing of the oil temperature and the temperature of the EGR cooler may be overcooled, or the coolant of the cylinder head of the relatively high temperature is supplied to the oil cooler and the EGR cooler such that the oil temperature may be overheated and the temperature of the EGR cooler may be overheated in a high temperature condition of the coolant. 
         [0009]    The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
       SUMMARY 
       [0010]    The present disclosure provides an engine system with a coolant control valve supplying the coolant having a desired temperature to the oil cooler and a EGR cooler depending the temperature of the coolant to improve the fuel consumption efficiency and to cool effectively an recirculation exhaust gas. 
         [0011]    An engine system with a coolant control valve according to one form of the present disclosure includes: a valve housing having a first valve space and a second valve space formed at both sides via a partition and including a connection passage formed in the partition; a first rotary valve disposed in the first valve space and having first coolant passages formed at a predetermined position from an interior circumference to an exterior circumference thereof, wherein one of the first coolant passages is formed at the position corresponding to the connection passage; a second rotary valve disposed in the second valve space and having second coolant passages formed at a predetermined position from an interior circumference to an exterior circumference thereof, wherein one of the second coolant passage is formed at a position corresponding to the connection passage; distribution lines respectively connected to positions corresponding to the first coolant passages and the second coolant passages that do not correspond to the connection passage in the valve housing and distributed with the coolant passing through the first rotary valve and the second rotary valve; and a driver disposed to rotate the first rotary valve and the second rotary valve, wherein the first and second coolant passages corresponding to the connection passage are connected to each other depending on the rotation positions of the first rotary valve and the second rotary valve. 
         [0012]    The coolant exhausted from the cylinder head may be supplied to the center of the first rotary valve, and the coolant exhausted from the cylinder block may be supplied to the center of the second rotary valve. 
         [0013]    The distribution lines may include a first distribution line connected to a heater core disposed to heat an inner air; a second distribution line connected to a radiator disposed to discharge the heat of the coolant; a third distribution line connected to an oil cooler disposed to heat or cool the oil circulating the engine; and a fourth distribution line connected to an EGR cooler disposed to cool the exhaust gas recirculating from the exhaust line to the intake line. 
         [0014]    The driver may include a motor; a drive gear rotated by the motor; a first driven gear externally meshed with the drive gear and disposed to be together rotated with the first rotary valve; and a second driven gear externally meshed with the first driven gear and disposed to be together rotated with the second rotary valve. 
         [0015]    A control portion controlling the driver depending on the temperature of the coolant may be further included. 
         [0016]    The control portion may control the rotation positions of the first rotary valve and the second rotary valve such that the coolant is not flowed to the first, second, third, and fourth distribution lines in a cooling state that the temperature of the coolant is lower than a first predetermined temperature. 
         [0017]    The control portion may control the rotation positions of the first rotary valve and the second rotary valve such that the coolant flows to the first distribution line and the coolant is not flowed to the second, third, and fourth distribution lines in a low temperature state that the temperature of the coolant is higher than the first predetermined temperature and is lower than a second predetermined temperature. 
         [0018]    The control portion may control the rotation positions of the first rotary valve and the second rotary valve such that the coolant flows to the first, third, and fourth distribution lines and the coolant is not flowed to the second distribution line and the first and second rotary valves open the connection passage in a warm state that the temperature of the coolant is higher than the second predetermined temperature and is lower than a third predetermined temperature. 
         [0019]    The control portion may control the rotation positions of the first rotary valve and the second rotary valve such that the coolant flows to the first, second, third, and fourth distribution lines and the first and second rotary valves close the connection passage in a hot state that the temperature of the coolant is higher than the third predetermined temperature. 
         [0020]    An engine system with a coolant control valve according to another form of the present disclosure includes: a valve housing having a first valve space and a second valve space formed at both sides via a partition and including a connection passage formed in the partition; a first rotary valve disposed in the first valve space and having first coolant passages formed at a predetermined position from an interior circumference to an exterior circumference thereof, wherein one of the first coolant passages is formed at the position corresponding to the connection passage; a second rotary valve disposed in the second valve space and having second coolant passages formed at a predetermined position from an interior circumference to an exterior circumference thereof, wherein one of the second coolant passage is formed at the position corresponding to the connection passage; distribution lines respectively connected to the positions corresponding to the first coolant passages and the second coolant passages that do not correspond to the connection passage in the valve housing and distributed with the coolant passing through the first rotary valve and the second rotary valve; and a control portion disposed to rotate the first rotary valve and the second rotary valve through the driver and selectively connecting the first and second coolant passages corresponding to the connection passage to each other. 
         [0021]    The control portion may control the rotation positions of the first rotary valve and the second rotary valve in the warm state that the temperature of the coolant is higher than a second predetermined temperature and is lower than a third predetermined temperature such that the first and second rotary valves open the connection passage, the coolant is supplied to the heater core through one among the first coolant passages of the first rotary valve, and the coolant is supplied to the oil cooler and the EGR cooler through the second coolant passages of the second rotary valve. 
         [0022]    The control portion may control the rotation positions of the first rotary valve and the second rotary valve in the hot state that the temperature of the coolant is higher than a third predetermined temperature such that the first and second rotary valves close the connection passage, the coolant is supplied to the heater core and the radiator through the first coolant passages of the first rotary valve, and the coolant is supplied to the oil cooler and the EGR cooler through the second coolant passages of the second rotary valve. 
         [0023]    According to the present disclosure, the coolant control valve is divided into the first and second valve spaces corresponding to the cylinder head and the cylinder block and selectively connects them depending on an operation condition such that the efficiency of the cooling system may be improved. 
         [0024]    Also, in the warm state, the first and second valve spaces are connected through the connection passage to mix the coolant to each other such that the coolant of the cylinder head of the relatively high temperature increases the temperature of the oil through the oil cooler, thereby reducing the fuel consumption and adjusting the temperature of the EGR cooler. 
         [0025]    Particularly, in the hot state, the first and second valve spaces are closed to each other such that the coolant exhaust from the cylinder head and the cylinder block is mixed to each other, thereby effectively cooling the oil cooler and the EGR cooler by using the coolant of the cylinder block in which the temperature of the coolant is relatively low. 
         [0026]    Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       DRAWINGS 
         [0027]    In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which: 
           [0028]      FIG. 1  is a flowchart showing an entire flow of a coolant in an engine system with a coolant control valve; 
           [0029]      FIG. 2  is a schematic cross-sectional view of a length direction of a coolant control valve; 
           [0030]      FIG. 3  is a schematic cross-sectional view of a width direction of a coolant control valve; and 
           [0031]      FIGS. 4 to 7  are flowcharts showing a flow of a coolant depending on an operation condition in an engine system. 
       
    
    
       [0032]    The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
       DETAILED DESCRIPTION 
       [0033]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
         [0034]      FIG. 1  is a flowchart showing an entire flow of a coolant in an engine system with a coolant control valve according to one form of the present disclosure. 
         [0035]    Referring to  FIG. 1 , an engine system includes: a heater core  100 , a coolant control valve  110 , a radiator  120 , a cylinder head  130 , a cylinder block  140 , an oil cooler  150 , an EGR cooler  160 , a coolant pump  170 , and a control portion  180 . 
         [0036]    The heater core  100  is disposed to warm an indoor air of a vehicle by using a supplied warm coolant, and the oil cooler  150  is disposed to execute a function of cooling an oil circulating in an engine or a transmission by using the supplied coolant. 
         [0037]    The EGR cooler  160  executes a function of cooling a recycled exhaust gas by using the supplied coolant, and the radiator  120  executes a function of discharging the heat of the supplied coolant. 
         [0038]    The cylinder head  130  is disposed on the cylinder block  140 , the coolant pump  170  pumps the coolant to one side of the cylinder block  140 , the part of the coolant supplied to the cylinder block  140  is supplied to one side lower part of the cylinder head  130 , and the rest passes through the cylinder block  140 . 
         [0039]    Also, a structure that the coolant exhausted from the cylinder head  130  and the coolant exhausted from the cylinder block  140  may be supplied to the coolant control valve  110  is provided. 
         [0040]    The coolant control valve  110  is set to distribute the coolant supplied from the cylinder head  130  to the heater core  100  and the radiator  120  and distribute the coolant supplied from the cylinder block  140  to the oil cooler  150  and the EGR cooler  160 . 
         [0041]    Also, the coolant supplied from the cylinder head  130  and the cylinder block  140  may be mixed to each other depending a driving condition. 
         [0042]    In one form, the control portion  180  controls the coolant control valve  110  depending on the operation condition of the engine or the temperature of the coolant, thereby effectively and rapidly controls the entire coolant system. 
         [0043]      FIG. 2  is a schematic cross-sectional view of a length direction of a coolant control valve according to one form of the present disclosure, and  FIG. 3  is a schematic cross-sectional view of a width direction of a coolant control valve according to one form of the present disclosure. 
         [0044]    Referring to  FIG. 2  and  FIG. 3 , the coolant control valve  110  includes: a first rotary valve  255   a , a sealing member  265 , a first coolant passage  250   a , a first valve space  276 , a drive gear  205 , a motor  200 , a first driven gear  210 , a connection passage  270 , a second driven gear  215 , a valve housing  260 , a second coolant passage  250   b , a second valve space  278 , a second rotary valve  255   b , and a partition  280 . Also, at a predetermined position outside of the valve housing  260 , a first distribution line  292 , a second distribution line  294 , a third distribution line  296 , and a fourth distribution line  298  are connected, respectively. 
         [0045]    The first valve space  276  is formed at the position corresponding to the cylinder head  130  in the upper side of the valve housing  260  and the second valve space  278  is formed at the position corresponding to the cylinder block  140  in the lower side. 
         [0046]    The partition  280  is formed between the first valve space  276  and the second valve space  278 , and the connection passage  270  connecting the first valve space  276  and the second valve space  278  to each other is formed in the partition  280 . 
         [0047]    In the first valve space  276 , the first rotary valve  255   a  of a pipe shape is disposed, and an interior circumference of the first valve space  276  and an exterior circumference of the first rotary valve  255   a  has a shape corresponding to each other. 
         [0048]    In the first rotary valve  255   a , three first coolant passages  250   a  are formed at a predetermined position from the interior circumference to the exterior circumference. In one form, the first coolant passage  250   a  is three, however it may be changed depending on a design specification. The center of the first coolant passages  250   a  is formed at the position corresponding to the connection passage  270 . 
         [0049]    Furthermore, the first distribution line  292  and the second distribution line  294  are connected by the valve housing  260  with a predetermined interval. The first and second distribution lines  292 ,  294  are disposed in the upper side of the valve housing  260 , and in the first rotary valve  255   a , the first coolant passage(s)  250   a  are respectively formed at the positions corresponding to the first and second distribution lines  292  and  294 . 
         [0050]    Accordingly, as the first rotary valve  255   a  is rotated, the first coolant passage(s)  250   a  may be communicated with the first distribution line and/or the second distribution line. According to one form, the coolant may be transferred via the first coolant passage(s)  250   a . The coolant profile may be formed inside of the first rotary valve  255   a  and communicated with the first and second distribution lines  292 ,  294  when the first rotary valve  255   a  is rotated. The position of coolant profile may be changed. 
         [0051]    Also, the sealing member  265  is interposed between the interior circumference of the first valve space  276  of the valve housing  260  and the exterior circumference of the first rotary valve  255   a . The sealing member  265  may inhibit or prevent the coolant distributed to the first distribution line  292  through the first coolant passage(s)  250   a  and the coolant distributed to the second distribution line  294  through the first coolant passage(s) from being leaved through the sealing structure. 
         [0052]    In one form of the present disclosure, the coolant exhausted from the cylinder head  130  is supplied to the center of the first rotary valve  255   a  through the upper part of one side of the valve housing  260 , and the supplied coolant is respectively distributed to the first distribution line  292  or the second distribution line  294  through the first coolant passage(s)  250   a . Here, the first distribution line  292  is connected to the heater core  100 , and the second distribution line  294  is connected to the radiator  120 . 
         [0053]    In the second valve space  278 , the second rotary valve  255   b  in a pipe shape is disposed, and the interior circumference of the second valve space  278  and the exterior circumference of the second rotary valve  255   b  have the shape corresponding to each other. 
         [0054]    In the second rotary valve  255   b , three second coolant passages  250   b  are formed at a predetermined position from the interior circumference to the exterior circumference. The three second coolant passages  250   b  are shown in  FIG. 2 , and the number of the second passages may be changed depending on a design specification. The center of the second coolant passages  250   b  is formed at a position corresponding to the connection passage  270 . 
         [0055]    Furthermore, the third distribution line  296  and the fourth distribution line  298  are connected by the valve housing  260  with a predetermined interval on the lower side of the valve housing  260 , and the second coolant passage  250   b (s) are respectively formed at positions corresponding to the third and fourth distribution lines  296  and  298  in the second rotary valve  255   b.    
         [0056]    Accordingly, as the second rotary valve  225   b  is rotated, the second coolant passage(s)  250   b  may be communicated with the third distribution line and/or the fourth distribution line. According to one form, the coolant may be transferred via the second coolant passage(s)  250   b , and the coolant profile may be formed inside of the second rotary valve  255   b  and communicated with the third and fourth distribution lines  296 ,  298  when the second rotary valve  255   b  is rotated. The position of coolant profile may be changed. 
         [0057]    Also, the sealing member  265  is interposed between the interior circumference of the second valve space  278  of the valve housing  260  and the exterior circumference of the second rotary valve  255   b , and the sealing member  265  may inhibit or prevent the coolant distributed to the third distribution line  296  through the second coolant passage  250   b  and the coolant distributed to the fourth distribution line  298  through the second coolant passage  250   b  from being leaving to the third distribution line  296  through the sealing structure. 
         [0058]    In another form of the present disclosure, the coolant exhausted from the cylinder block  140  is supplied to the center of the second rotary valve  255   b  through the lower part of one side of the valve housing  260 , and the supplied coolant is respectively distributed to the third distribution line  296  or the fourth distribution line  298  through the second coolant passage  250   b . Here, the third distribution line  296  is connected to the oil cooler  150 , and the fourth distribution line  298  is connected to the EGR cooler  160 . 
         [0059]    The first driven gear  210  that is rotated along with the first rotary valve  255   a  is disposed at the other side of the valve housing  260  and the second driven gear  215  that is rotated along with the second rotary valve  255   b  is disposed, and the first driven gear  210  and the second driven gear  215  are externally meshed to each other. 
         [0060]    Meanwhile, the first driven gear  210  and the second gear  215  may have a predetermined gear ratio. In one, the number of teeth of the first driven gear  210  may be larger than the number of teeth of the second driven gear  215 . The first driven gear  210  which rotates the first rotary valve  255   a  received relatively higher temperature coolant may be controlled delicately. For example, the ratio between the first driven gear  210  and the second driven gear  215  may be 1.2. 
         [0061]    Also, the first driven gear  210  and the drive gear  205  are externally meshed, and the motor  200  is disposed to rotate the first drive gear  205 . 
         [0062]    When the control portion  180  (e.g., an engine control unit “ECU”) outputs signals to rotate the motor  200 , the drive gear  205  rotates the first driven gear  210  and the first rotary valve  255   a . The first driven gear  210  rotates the second driven gear  215  and the second rotary valve  255   b.    
         [0063]    Accordingly, both the first and second rotary valves  255   a  and  255   b  may be simultaneously controlled through one motor  200 . The connection passage  270  may be selectively connected depending on the rotation position of the first and second rotary valves  255   a  and  255   b , and the coolant may be selectively distributed to the first, second, third, and fourth distribution lines  292 ,  294 ,  296 , and  298 . 
         [0064]      FIGS. 4 to 7  are flowcharts showing a flow of a coolant depending on an operation condition in an engine system according to the present disclosure. 
         [0065]    Referring to  FIG. 4 , in a cooling state that the temperature of the coolant is lower than a first predetermined temperature, the control portion  180  controls the motor  200  to control the rotation positions of the first rotary valve  255   a  and the second rotary valve  255   b  for the coolant not to be flowed to the first, second, third, fourth distribution lines, and the connection passage  292 ,  294 ,  296 ,  298 , and  270 . Accordingly, the coolant passing through the cylinder head  130  and the cylinder block  140  is stopped or reduced, thereby shortening a warming up time of the engine. 
         [0066]    The first predetermined temperature of coolant may be below 40 degrees. 
         [0067]    Referring to  FIG. 5 , in a low temperature that the temperature of the coolant is higher than first predetermined temperature and is lower than a second predetermined temperature, the control portion  180  controls the motor  200  to control the rotation positions of the first rotary valve  255   a  and the second rotary valve  255   b  such that the coolant flows to the first distribution line  292 , and the coolant does not flow to the second, third, and fourth distribution lines  294 ,  296 , and  298 . 
         [0068]    Accordingly, by using the coolant which passes through the cylinder head  130  and is relatively high temperature, the coolant may be appropriately distributed to the heater core  100 , and heats the heater core  100 . Here, the connection passage  270  is closed such that the coolant passing through the cylinder head  130  is supplied to the first rotary valve  255   a . The second predetermined temperature of coolant may be 60 degrees. 
         [0069]    Referring to  FIG. 6 , in the warm state that the temperature of the coolant is higher than the second predetermined temperature and is lower than a third predetermined temperature, the control portion  180  controls the motor  200  to control the rotation positions of the first rotary valve  255   a  and the second rotary valve  255   b  such that the coolant flows to the first, third, and fourth distribution lines  292 ,  296 , and  298  and the coolant does not flow to the second distribution line  294 . 
         [0070]    Accordingly, by using the coolant passing through the cylinder head  130  and the cylinder block  140 , the coolant may be appropriately distributed to the heater core  100 , the EGR cooler  160 , and the oil cooler  150 . In this case, the first and the second coolant passage  250   a  and  250   b  of the first rotary valve  255   a  and the second rotary valve  255   b  are communicated each other, and the connection passage  270  is opened. Therefore, the coolant passing through the cylinder head  130  and the cylinder block  140  may be respectively supplied to the first rotary valve  255   a  and the second rotary valve  255   b  and may be mixed together. 
         [0071]    Here, the coolant that is discharged from the cylinder head  130  and has the relatively high temperature is supplied to the oil cooler  150  and the EGR cooler  160  such that the fuel consumption may be improved and the temperature of the EGR cooler  160  may be appropriately adjusted by the increasing of the temperature of the engine oil. In addition, the heater core  100  is heated by the coolant passing through the first rotary valve  255   a  of cylinder head  130  into the first distribution line  292 . 
         [0072]    The third predetermined temperature of coolant may be 90 degrees. 
         [0073]    Referring to  FIG. 7 , in a hot state that the temperature of the coolant is higher than the third predetermined temperature, the control portion  180  controls the motor  200  to control the rotation positions of the first rotary valve  255   a  and the second rotary valve  255   b  such that the coolant flows to the first, second, third, and fourth distribution lines  292 ,  294 ,  296 , and  298 , thereby controlling the entire positions. 
         [0074]    Accordingly, by using the coolant passing through the cylinder head  130  and the cylinder block  140 , the coolant may be appropriately distributed to the heater core  100 , the oil cooler  150 , the EGR cooler  160 , and the radiator  120 . 
         [0075]    In this case, the connection passage  270  between the first rotary valve  255   a  and the second rotary valve  255   b  is closed such the first and the second coolant passage  250   a  and  250   b  are not communicated each other. In other words, the coolant passing through the cylinder head  130  and the cylinder block  140  may be separately supplied to the first rotary valve  255   a  and the second rotary valve  255   b  respectively. From this structure, the coolant which is relatively high temperature passing through the cylinder head is supplied into and cooled by the radiator  120  and heats the heater core  100 . And the coolant which is relatively lower temperature passing through the cylinder block  140  cools the EGR cooler  160  and the oil cooler  150 . 
         [0076]    While this present disclosure has been described in connection with what is presently considered to be practical exemplary forms, it is to be understood that the present disclosure is not limited to the disclosed forms. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 
         [0000]    
       
         
               
             
               
               
               
             
           
               
                   
               
               
                 &lt;Description of symbols&gt; 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 100: heater core 
                 110: coolant control valve 
               
               
                   
                 120: radiator 
                 130: cylinder head 
               
               
                   
                 140: cylinder block 
                 150: oil cooler 
               
               
                   
                 160: EGR cooler 
                 170: coolant pump 
               
               
                   
                 180: control portion 
                 200: motor 
               
               
                   
                 205: drive gear 
                 210: first driven gear 
               
               
                   
                 215: second driven gear 
                 250a: first coolant passage 
               
               
                   
                 250b: second coolant passage 
                 255a: first rotary valve 
               
               
                   
                 255b: second rotary valve 
                 260: valve housing 
               
               
                   
                 265: sealing member 
                 270: connection passage 
               
               
                   
                 276: first valve space 
                 278: second valve space 
               
               
                   
                 280: partition 
                 292: first distribution line 
               
               
                   
                 294: second distribution line 
                 296: third distribution line 
               
               
                   
                 298: fourth distribution line