Patent Publication Number: US-2011067668-A1

Title: Oil supply device for vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 U.S.C. §119 to Japanese Patent Application 2009-219058, filed on Sep. 24, 2009, the entire content of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     This disclosure relates to an oil supply device for a vehicle. 
     BACKGROUND DISCUSSION 
     A known engine oil supply device disclosed in JP2004-143972A (hereinafter referred to as Reference 1) includes a mechanical oil pump, an electric oil pump, and a switching valve selectively varying a supply of oil from the electric oil pump to a variable valve timing device and an oil jet device. The mechanical oil pump is connected to the electric oil pump in order to allow the oil pump to operate at low power. 
     A known oil pump disclosed in JP2008-291825A (hereinafter referred to as Reference 2) includes a relative position varying means controlled by a hydraulic control valve. A relative position between central axes of inner and outer rotors is varied by the relative position varying means in order to prevent an unneeded operation of the oil pump. 
     In an oil supply device for a vehicle, for the purpose of an appropriate supply of oil from an oil pump, for example, a supply condition of the oil from the oil pump to a variable valve timing device (hydraulic actuator) and an oil jet device (oil lubricating system) is desired to vary at start of an internal combustion engine or depending on operating conditions of the internal combustion engine. In addition, a supply condition of the oil from the oil pump is expected to vary in order to prevent the oil pump from excessively supplying the oil to the hydraulic actuator and the oil lubricating system when the internal combustion engine is operated at high speed. Accordingly, it is assumed that a technique according to the engine oil supply device described in Reference 1 and a technique according to the oil pump described in Reference 2 are combined with each other. 
     However, in the case where the techniques disclosed in Reference 1 and Reference 2 are combined, the switching valve varying the supply condition of the oil from the electric oil pump to the hydraulic actuator and the oil lubricating system and multiple control valves of the hydraulic control valve controlling the relative position varying means are required for the oil supply device. As a result, the size and cost of the oil supply device may be increased. 
     A need thus exists for an oil supply device for a vehicle, which is not susceptible to the drawback mentioned above. 
     SUMMARY 
     According to an aspect of this disclosure, an oil supply device for a vehicle includes an oil pump having a supply condition varying mechanism varying a supply condition of oil, a hydraulic actuator to which the oil is supplied from the oil pump, a lubricating system to which the oil is supplied from the oil pump, and an oil supply adjusting mechanism adjusting the supply condition of the oil from the oil pump to the hydraulic actuator and the lubricating system, wherein the supply condition of the oil to the supply condition varying mechanism and the oil supply adjusting mechanism is controlled by a single control valve. 
     According to another aspect of the disclosure, an oil supply device for a vehicle includes a hydraulic actuator provided at an internal combustion engine and being operated by a hydraulic pressure, a lubricating system lubricating the internal combustion engine, an oil pump including a supply condition varying mechanism and supplying the oil to the hydraulic actuator and the lubricating system, the supply condition varying mechanism varying a discharge rate of the oil, an oil supply adjusting mechanism arranged between the hydraulic actuator and the oil pump and between the lubricating system and the oil pump and distributing the oil, which is discharged from the oil pump, to the hydraulic actuator and the lubricating system, wherein a supply condition of the oil to the supply condition varying mechanism and the oil supply adjusting mechanism is controlled by a single control valve. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing and additional features and characteristics of this disclosure will become more apparent from the following detailed description considered with the reference to the accompanying drawing, wherein: 
         FIG. 1  is an oil passage routing chart of an oil supply device for a vehicle according to an embodiment disclosed here. 
     
    
    
     DETAILED DESCRIPTION 
     An oil supply device  100  for a vehicle according to an embodiment will be explained with reference to an illustration of a drawing as follows.  FIG. 1  is an oil passage routing chart of the oil supply device  100  according to the embodiment. The oil supply device  100  includes an oil pump  10 , a hydraulic actuator  30  to which oil is supplied from the oil pump  10 , an engine lubricating system (lubricating system)  40  to which the oil is supplied from the oil pump  10 , an oil supply adjusting valve (oil supply adjusting mechanism)  50 , and an oil control valve (control valve)  60 . The oil pump  10  is driven by an internal combustion engine while including a supply condition varying mechanism  20  that varies a supply condition (discharge rate) of the oil. The hydraulic actuator  30  is arranged at the internal combustion engine while being operated by a hydraulic pressure of the oil. The oil supply adjusting valve  50  distributes the oil, which is discharged from the oil pump  10 , to the hydraulic actuator  30  and the engine lubricating system  40  and adjusts the supply condition of the oil to the hydraulic actuator  30  and the engine lubricating system  40 . The oil control valve  60  controls the supply condition of the oil to the supply condition varying mechanism  20  and the oil supply adjusting valve  50 . 
     A first oil passage  11  is arranged between the oil pump  10  and the hydraulic actuator  30 . The oil from the oil pump  10  is supplied via the first oil passage  11  to the hydraulic actuator  30 . The oil from the hydraulic actuator  30  is drained from an oil drain passage  31  connected to the hydraulic actuator  30 . 
     A second oil passage  12  is arranged between the oil pump  10  and the engine lubricating system  40 . The second oil passage  12  is diverged from the first oil passage  11 . The oil from the oil pump  10  is supplied to the engine lubricating system  40  via the second oil passage  12 . Further, the oil from the engine lubricating system  40  is drained from an oil drain passage  41  connected to the engine lubricating system  40 . The oil supply adjusting valve  50  is connected to the second oil passage  12  so as to be positioned between the oil pump  10  and the engine lubricating system  40  and between the oil pump  10  and the hydraulic actuator  30 . 
     The oil pump  10  includes a spring  21  and the supply condition varying mechanism  20 . The spring  21  is arranged at one side of a protruding portion protruding from a retaining portion rotatably retaining an outer rotor. The supply/discharge of the oil between the oil control valve  60  and a hydraulic chamber  22  is performed by the supply condition varying mechanism  20  so that an eccentric position of the outer rotor relative to an inner rotor is varied. As a result, the oil pump  10  varies the supply condition of the oil. The hydraulic chamber  22  is arranged at the other side of the protruding portion protruding from the retaining portion and is separated from the one side of the protruding portion in a liquid-tight manner. Further, the oil pump  10  suctions the oil from an oil pan  80  via an oil suction passage  14  and discharges the oil to the first oil passage  11  via an oil filter  90 . 
     The oil supply adjusting valve  50  includes a valve body  51  formed into a stepped cylindrical shape having a small diameter cylindrical portion  51 A and a large diameter cylindrical portion  51 B. A connecting portion  51   a  connecting to the second oil passage  12  and a connecting portion  51   b  connecting to a third oil passage  13  configuring a portion of the second oil passage  12  and communicating with the engine lubricating system  40  are arranged at the small diameter cylindrical portion  51 A. The connecting portion  51   a  is positioned closer to the second oil passage  12  than the connecting portion  51   b.  A connecting portion  51   c  connecting to the oil control valve  60  is arranged at the large diameter cylindrical portion  51 B. A valve  52  is slidably arranged within the valve body  51 . The valve  52  includes a cylindrical portion  52   a,  a small diameter portion  52   b,  and a large diameter portion  52   c.  The cylindrical portion  52   a  slides within the small diameter cylindrical portion  51 A to connect and disconnect a communication between the connecting portion  51   a  and the connecting portion  51   b.  The small diameter portion  52   b  is continuously formed with the cylindrical portion  52   a  while separating the small diameter cylindrical portion  51 A from the large diameter cylindrical portion  51 B in a liquid-tight manner. The large diameter portion  52   c  is continuously formed with the small diameter portion  52   b  while sliding within the large diameter cylindrical portion  51 B and separating the small diameter cylindrical portion  51 A from the large diameter cylindrical portion  51 B in a liquid-tight manner. A slit  52   d  is formed in the cylindrical portion  52   a.  The slit  52   d  communicates between inner and outer sides of the cylindrical portion  52   a  formed in a notched shape facing the connecting portion  51   b.    
     The small diameter cylindrical portion  51 A, the connecting portion  51   a,  the connecting portion  51   b,  the cylindrical portion  52   a,  the small diameter portion  51   b,  and the slit  52   d  vary the supply condition of the oil to the engine lubricating system  40  while configuring an oil passage control portion  53  that varies the supply condition of the oil to the hydraulic actuator  30 . The large diameter cylindrical portion  51 B, the connecting portion  51   c,  and the large diameter portion  52   c  configure a pressure chamber  54  sliding therein the valve  52 . The large diameter portion  52   c  has a diameter larger than a diameter of the small diameter portion  52   b.  For example, when the same magnitude pressure is applied to the large diameter portion  52   c  and the small diameter portion  52   b , a force acting from the large diameter portion  52   c  (pressure chamber  54 ) to the small diameter portion  52   b  (oil passage control portion  53 ) is generated to the valve  52 . 
     The oil control valve  60  includes an oil passage  61   a  connecting to the second oil passage  12  leading to the oil pump  10 , an oil passage  61   b  connecting to the hydraulic chamber  22  (supply condition varying mechanism  20 ), an oil passage  61   c  connecting to the pressure chamber  54  (oil supply adjusting valve  50 ), and a valve body  61  to which an oil drain passage  61   d  is connected. The oil of the valve body  61  is drained to the oil pan  80  via the oil drain passage  61   d . A spool  62  and a solenoid  63  that drives the spool  62  are attached to the valve body  61 . The spool  62  switches a connection between the oil passages  61   a,    61   b,  and  61   c  and the oil drain passage  61   d.  The oil control valve  60  is controlled by a duty ratio based on a signal of an ECU  70  computing a detection value from a pressure status of the oil in the hydraulic actuator  30  and the engine lubricating system  40  and rotations of the internal combustion engine, and the like. The ECU  70  controls the oil control valve  60  on the basis of the duty ratio to switch a flow of the oil from the oil control valve  60  via the oil passage  61  b to the hydraulic chamber  22  and a flow of the oil from the oil control valve  60  to the pressure chamber  54  via the oil passage  61   c  and to the oil drain passage  61   d  via the oil passage  61   c.    
     An operation of the oil supply device  100  will be explained as follows. According to the oil supply device  100  of the embodiment, when the internal combustion engine starts or rotates at low speed, the oil control valve  60  is controlled based on a duty ratio (for example, the oil control valve  60  is energized at zero or one hundred percent duty cycle) by the ECU  70  so as to be in Condition A (a first position) shown in the most right in  FIG. 1  and the oil passage  61   b  connecting to the hydraulic chamber  22  and the oil passage  61   c  connecting to the pressure chamber  54  are connected to the oil drain passage  61   d.  At this time, the oil pump  10  is configured so that the eccentric position of the outer rotor relative to the inner rotor is set at a large value by the supply condition varying mechanism  20  and that a discharge rate of the oil is high. The connecting portion  51   b  is opened by the valve  52  slid toward the pressure chamber  54  by the oil flowing into the oil passage control portion  53 ; thereby, the oil is supplied to the engine lubricating system  40 . Further, the oil discharged from the oil pump  10  is supplied to the hydraulic actuator  30  via the first oil passage  11 . An oil supply limiting means limiting a supply of the oil from the oil pump  10  to the hydraulic actuator  30  is not arranged therebetween. Accordingly, the oil is consistently supplied from the oil pump  10  to the hydraulic actuator  30  under Condition A (the first condition). Consequently, a non-operational state of the hydraulic actuator  30  due to no supply of the oil may be prevented. 
     Further, when the oil is not supplied sufficiently to operate the hydraulic actuator  30 , for example, in the case where the discharge rate of the oil from the oil pump  10  is low, the oil control valve  60  is controlled based on a duty ratio (for example, the oil control valve  60  is energized at fifty percent duty cycle) by the ECU  70  so as to be in Condition B (a second position) shown in the intermediate position in  FIG. 1 . Further, the oil passage  61   b  connecting to the hydraulic chamber  22  is connected to the oil drain passage  61   d  and the oil passage  61   a  communicating with the oil pump  10  via the second oil passage  12  is connected to the pressure chamber  54 . At this time, the oil pump  10  is configured so that the large value of the eccentric position of the outer rotor relative to the inner rotor is maintained by the supply condition varying mechanism  20  and that the discharge rate of the oil is high. The connecting portion  51   b  is closed by the valve  52  slid toward the oil passage control portion  53  by the oil supplied to the pressure chamber  54 ; thereby the oil to be supplied to the engine lubricating system  40  is limited and the oil is supplied to the hydraulic actuator  30 . In addition, a minimum volume of the oil required for the engine lubricating system  40  is supplied by the slit  52   d.  In other words, when the oil control valve  60  is under Condition B (the second position), the supply of the oil to the engine lubricating system  40  is limited and a limited volume of the oil is supplied to the hydraulic actuator  30 . Accordingly, the oil supply adjusting valve  50  serves as a throttle valve supplying the oil preferentially to the hydraulic actuator  30  rather than to the engine lubricating system  40 . As described above, even when the discharge rate of the oil from the oil pump  10  is low, the hydraulic actuator  30  may not be brought into the non-operational state due to an insufficient hydraulic pressure while the supply of the oil to the engine lubricating system  40  is limited (reduced). However, in the case of the oil pump  10  that is a mechanical oil pump receiving the rotations of the internal combustion engine so as to be driven, for example, when a discharge rate of the oil of the oil pump  10  is low, the number of rotations of the internal combustion engine is small. Accordingly, slide members configuring the engine lubricating system  40  are slid at low speed of the internal combustion engine; therefore, lubrication of the internal combustion engine may be performed with a small volume of the oil. As a result, although the supply of the oil to the engine lubricating system  40  is limited (reduced), overheating, seizure, and the like of the engine lubricating system  40  due to an insufficient lubrication may be inhibited. 
     Furthermore, in the case where the hydraulic actuator  30  is in operation while the internal combustion engine is operated at medium or high speed, the oil control valve  60  is controlled based on a duty ratio (for example, the oil control valve  60  is energized at one hundred or zero percent duty cycle) by the ECU  70  so as to be in Condition C (a third position) shown in the most left side relative to the ECU  70  in  FIG. 1 . Further, the hydraulic chamber  22  connects to the second oil passage  12  which communicates with the oil pump  10 , via the oil passage  61   b  and the oil passage  61   c  while the pressure chamber  54  connects to the second oil passage  12  via the oil passage  61   c  and the oil passage  61   a.  At this time, the oil pump  10  is configured so that the eccentric position of the outer rotor relative to the inner rotor is set at a small value by the supply condition varying mechanism  20  and that the discharge rate of the oil is low; thereby the oil is prevented from being excessively supplied. The connecting portion  51   b  is closed by the valve  52  slid toward the oil passage control portion  53  by the oil supplied to the pressure chamber  54 ; thereby, the supply of the oil from the oil pump  10  to the engine lubricating system  40  is limited and the oil is supplied to the hydraulic actuator  30 . In addition, the minimum volume of the oil required for the engine lubricating system  40  is supplied by the slit  52   d.  In other words, when the oil control valve  60  is under Condition C (the third position), the oil supply adjusting valve  50  serves as the throttle valve supplying the oil preferentially to the hydraulic actuator  30  rather than to the engine lubricating system  40  and the discharge rate of the oil from the oil pump  10  is reduced by the supply condition varying mechanism  20 . Accordingly, the volume of the oil to be supplied to the hydraulic actuator  30  and the engine lubricating system  40  that are oil supply destinations is reduced by the supply condition varying mechanism  20  and the volume of the oil to be supplied to the engine lubricating system  40  is minimized by the oil supply adjusting valve  50 . As described above, even when the discharge rate of the oil from the oil pump  10  increases, the volume of the oil to be supplied to the hydraulic actuator  30  and the engine lubricating system  40  is secured and the oil may be prevented from being supplied to the hydraulic actuator  30  and the engine lubricating system  40  more than necessary. 
     Thus, according to the oil supply device  100  of the embodiment, the supply condition of the oil relative to the hydraulic actuator  30  and the engine lubricating system  40  is varied depending on operating conditions of the internal combustion engine from the start of the operation to the operation at high speed and the supply condition of the oil from the oil pump  10  is varied. Consequently, the oil may be appropriately supplied to the internal combustion engine by the oil supply device  100 . 
     In addition, the supply condition of the oil from the oil control valve  60  to the hydraulic actuator  30 , the engine lubricating system  40 , and the supply condition varying mechanism  20  of the oil pump  10  is controlled based on the duty ratio. Accordingly, the supply condition of the oil is controlled by the single oil control valve  60 . As a result, the size and cost of the oil supply device  100  may be reduced and the oil supply device  100  may be simplified. Moreover, the oil supply device  100  may be downsized and simplified only by arranging the oil drain passage  61   d  at the oil control valve  60 . 
     As described above, the oil pump  10  varying the supply condition of the oil is applied to the oil supply device  100  of the embodiment; therefore, an additional oil pump is not required. Further, the supply condition of the oil to the hydraulic actuator  30  and the engine lubricating system  40  is controlled by the single oil control valve  60  to thereby control the supply condition of the oil to the supply condition varying mechanism  20  and the oil supply adjusting valve  50 . Accordingly, the size and cost of the oil supply device  100  are reduced and the oil supply device  100  is simplified. Furthermore, the oil is drained from the oil control valve  60  via the single oil drain passage  61   d , leading to the reduction of the size and cost of the oil supply device  100 . 
     According to the aforementioned embodiment, the oil supply adjusting valve  50  is configured to consistently supply the oil to the hydraulic actuator  30  and the engine lubricating system  40 . 
     According to the aforementioned embodiment, the oil supply device  100  further includes the first oil passage  11  supplying the oil from the oil pump  10  to the hydraulic actuator  30  and the second oil passage  12  supplying the oil from the oil pump  10  to the engine lubricating system  40 . The second oil passage  12  is diverged from the first oil passage  11 . The oil supply adjusting valve  50  is connected to the second oil passage  12  so as to be positioned between the oil pump  10  and the engine lubricating system  40 . 
     Since the oil supply adjusting valve  50  is arranged as described above, an oil passage route may be simplified. 
     According to the aforementioned embodiment, the oil control valve  60  is controlled based on the duty ratio to vary the supply condition of the oil to the supply condition varying mechanism  20 , the hydraulic actuator  30 , and the engine lubricating system  40 . 
     Accordingly, the supply condition of the oil to the hydraulic actuator  30  and the engine lubricating system  40  is independently controlled based on the duty ratio by the single oil control valve  60 . 
     According to the aforementioned embodiment, the oil supply adjusting valve  50  includes the oil passage control portion  53  connecting to the second oil passage  12  and the pressure chamber  54  connecting to the oil control valve  60 . Further, the oil passage control portion  53  is connected to the engine lubricating system  40  via the third oil passage  13  configuring a portion of the second oil passage  12 . 
     Accordingly, the oil supply adjusting valve  50  is simply configured to control the supply condition of the oil to the hydraulic actuator  30  in accordance with the supply condition of the oil in the pressure chamber  54 . 
     According to the aforementioned embodiment, the oil control valve  60  includes the first position (Condition) A where the oil is not supplied to both of the supply condition varying mechanism  20  and the pressure chamber  54 , the second position (Condition) B where the oil is supplied to either the supply condition varying mechanism  20  or the pressure chamber  54 , and the third position (Condition) C where the oil is supplied to both of the supply condition varying mechanism  20  and the pressure chamber  54 . 
     Accordingly, the supply condition of the oil to the hydraulic actuator  30  and the engine lubricating system  40  is independently controlled by the single oil control valve  60  that is easily configured only by having the first position A, the second position B, and the third position C. 
     According to the aforementioned embodiment, the oil supply adjusting valve  50  limits the supply of the oil to the engine lubricating system  40  when the oil is supplied to the pressure chamber  54 . 
     Accordingly, the supply of the oil to the engine lubricating system  40  that is one of supply destinations of the oil supplied from the oil pump  10  is limited; thereby the oil is preferentially supplied to the hydraulic actuator  30  that is the other of the supply destinations of the oil supplied from the oil pump  10 . 
     According to the aforementioned embodiment, the oil pump  10  limits the supply of the oil to the hydraulic actuator  30  and the engine lubricating system  40  when the oil is supplied to the supply condition varying mechanism  20 . 
     Accordingly, the discharge rate of the oil from the oil pump  10  is limited; therefore, the supply of the oil to the hydraulic actuator  30  and the engine lubricating system  40  is reduced. 
     The principles, preferred embodiment and mode of operation of the present invention have been described in the foregoing specification. However, the invention which is intended to be protected is not to be construed as limited to the particular embodiments disclosed. Further, the embodiments described herein are to be regarded as illustrative rather than restrictive. Variations and changes may be made by others, and equivalents employed, without departing from the spirit of the present invention. Accordingly, it is expressly intended that all such variations, changes and equivalents which fall within the spirit and scope of the present invention as defined in the claims, be embraced thereby.