Patent Publication Number: US-2015059670-A1

Title: Variable valve timing control device

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 U.S.C. §119 to Japanese Patent Application 2013-177121, filed on Aug. 28, 2013, the entire content of which is incorporated herein by reference. 
     TECHNICAL FIELD 
     This disclosure generally relates to a variable valve timing control device. 
     BACKGROUND DISCUSSION 
     A known variable valve timing control device favorably includes a driven side rotation member which is formed with a lightweight material which has small rotation inertia in order to easily change a relative rotational phase of the driven side rotation member relative to a driving side rotation member. Therefore, the driven side rotation member is generally made from a low strength material, for example, an aluminum material. On the other hand, a camshaft connected to the driven side rotation member is generally made from a high-strength material, for example, an iron material. Thus, a gap is easily formed at an interface between the driven side rotation member and the camshaft due to a difference between a coefficient of linear expansion of the driven side rotation member and a coefficient of linear expansion of the camshaft. Along with that, the driven side rotation member may be easily damaged because the high-strength camshaft is directly in contact with the low-strength driven side rotation member. 
     Especially, in a case where a flow path of the operation fluid which changes a relative rotational phase of the driven side rotation member relative to the driving side rotation member extends over the driven side rotation member and the camshaft, and the gap is generated at the interface of the driven side rotation member and the camshaft, the relative rotational phase cannot be changed precisely at the right time, or proper timing because of the leakage of the operation fluid via the gap. 
     A known variable valve timing control device is disclosed in JP2012-57578A (hereinafter referred to as Patent reference 1). The variable valve timing control device disclosed in Patent reference 1 is provided with a driving side rotation member (housing), a driven side rotation member (inner rotor), and a fluid pressure chamber defined between the driving side rotation member and the driven side rotation member, and a first flow path and a second flow path allowing an operation fluid to flow in or flow out of the fluid pressure chamber. The variable valve timing control device further includes an intermediate member between an inner circumferential surface of the driven side rotation member and an outer circumferential surface of the camshaft and connects the driven side rotation member and the camshaft. A space configuring a part of the first flow path is defined between the driven side rotation member and the camshaft, whereas a part of the second flow path is placed at the intermediate member. A contact portion where the intermediate member is in contact with the driven side rotation member is provided between the first flow path and the second flow path. The driven side rotation member is made from an aluminum material, whereas the intermediate member is made from an iron material. 
     According to the variable valve timing control device disclosed in Patent reference 1, because the variable valve timing control device includes the intermediate member which is positioned between the inner circumferential surface of the driven side rotation member and the outer circumferential surface of the camshaft, to connect the driven side rotation member and the camshaft, the driven side rotation member made from the aluminum material does not come in contact with the camshaft. Thus, in a case where the camshaft is made from a high-strength material, the driven side rotation member made from the aluminum material may be prevented from being damaged. Further, because the intermediate member is made from the iron material which includes a coefficient of linear expansion that is close to a coefficient of linear expansion of the camshaft which is made from the high-strength material, the gap is not generated at the interface of the intermediate member and the camshaft. Accordingly, in a case where the flow path of the operation fluid extends over the intermediate member and the camshaft, the operation fluid does not leak easily. However, as a result of mounting the intermediate member inwardly of the driven side rotation member between the driven side rotation member and the camshaft in order to prevent the driven side rotation member and the camshaft from being in contact with each other, the space formed between the driven side rotation member and the camshaft corresponds to the part of the first flow path, whereas the part of the second flow path is provided at the intermediate member. Thus, in a state where a gap is generated at an interface between the driven side rotation member and the intermediate member, the first flow path and the second flow path communicate with each other via the gap, and the operation fluid leaks out of and flows into the first and second flow paths. Accordingly, the relative rotational phase of the driven side rotation member relative to the driving side rotation member may not be changed precisely at the right time, or proper timing. Thus, in order to change the relative rotational phase of the driven side rotation member relative to the driving side rotation member precisely at the right time, or proper timing, the contact portion where the intermediate member and the driven side rotation member come in contact with each other in the entire circumference between the first and second flow paths is provided to prevent the operation fluid from leaking out of and flowing into the first and second flow paths. 
     According to the variable valve timing control device disclosed in Patent reference 1, the intermediate member is inserted from an end of the driven side rotation member to be positioned between the inner circumference of the driven side rotation member and an outer circumference of the camshaft. Thus, after mounting the driven side rotation member and the intermediate member to the driving side rotation member, the intermediate member may easily come out of the driven side rotation member when the camshaft is mounted to the variable valve timing control device. Accordingly, the mounting process of the variable valve timing control device may be complicated. Further, in a case where the intermediate member is press-fitted into the driven side rotation member, a gap may be generated between the intermediate member and the driven side rotation member because of a resistance force applied when the intermediate member is press-fitted into the driven side rotation member. The first and second flow paths communicate with each other via the gap, leading to the inferior operation. 
     A need thus exists for a variable valve timing control device which is not susceptible to the drawback mentioned above. 
     SUMMARY 
     According to an aspect of this disclosure, a variable valve timing control device includes a driving side rotation member configured to synchronously rotate with a driving shaft of an internal combustion engine, a driven side rotation member provided inwardly of the driving side rotation member to be coaxial with the driving side rotation member, the driven side rotation member integrally rotating with a camshaft for opening and closing a valve of the internal combustion engine, a fluid pressure chamber defined between the driving side rotation member and the driven side rotation member, a first flow path and a second flow path allowing a flow of an operation fluid into and out of the fluid pressure chamber to change a relative rotational phase of the driven side rotation member relative to the driving side rotation member between a most advanced angle phase and a most retarded angle phase, an intermediate member being provided between an inner circumferential surface of the driven side rotation member and an outer circumferential surface of the camshaft, the intermediate member connecting the driven side rotation member and the camshaft, and a contact portion where the intermediate member and the driven side rotation member come in contact with each other at a position between the first flow path and the second flow path when mounting the intermediate member to the camshaft after mounting the intermediate member and the driven side rotation member to the driving side rotation member after mounting the intermediate member to the driven side rotation member by press-fitting in a state where a space configuring a part of the first flow path is defined between the driven side rotation member and the camshaft and the intermediate member includes a part of the second flow path. 
    
    
     
       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 drawings, wherein: 
         FIG. 1  is a cross sectional view illustrating an entire configuration of a variable valve timing control device according to a first embodiment disclosed here; 
         FIG. 2  is a cross-sectional view of the variable valve timing control device taken along line II-II in  FIG. 1 ; 
         FIG. 3  is a detailed view of an oil control valve when controlling a relative rotational phase of a driven side rotation member relative to a driving side rotation member to establish an advanced angle position; 
         FIG. 4  is a detailed view of the oil control valve when controlling the relative rotational phase of the driven side rotation member relative to the driving side rotation member to establish a retarded angle position; 
         FIG. 5  is an exploded perspective view partially illustrating the configuration of the variable valve timing control device; 
         FIG. 6  is a cross sectional view illustrating an entire configuration of a variable valve timing control device according to a second embodiment; and 
         FIG. 7  is a cross sectional view partially explaining a configuration of a variable valve control device according to a third embodiment: 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of a variable valve timing control device for controlling, or regulating the timing for opening and closing an intake valve of an engine for a vehicle will be explained hereunder with reference to the drawings. 
     A first embodiment of the variable valve timing control device of this disclosure will be explained with reference to  FIGS. 1 to 5 . 
     As shown in  FIGS. 1 and 2 , the variable valve timing control device includes a driving side rotation member  1  (a housing) and a driven side rotation member  2  (an inner rotor). The aluminum-alloy-made driving side rotation member  1  synchronously rotates with a crankshaft of an engine for a vehicle. The aluminum-alloy-made driven side rotation member  2  is positioned inwardly of the driving side rotation member  1  to be coaxial with the driving side rotation member  1 . The driven side rotation member  2  integrally rotates with a camshaft  10  which opens and closes an intake valve of the engine. 
     The driven side rotation member  2  is relatively rotatably supported by the driving side rotation member  1 . The camshaft  10  is coaxially configured with a camshaft body  10   a  and a steel-made oil control valve bolt  10   b,  or a steel-made OCV bolt  10   b.  The steel-made OCV bolt  10   b  is coaxially positioned within the driven side rotation member  2  and is screwed and fixed to the camshaft body  10   a.  The engine for the vehicle corresponds to an internal combustion engine, whereas the crankshaft corresponds to a driving shaft of the internal combustion engine. 
     A steel-made intermediate rotation member  6  serving as an intermediate member is provided between an inner circumference of the driven side rotation member  2  and an outer circumferential surface of the OCV bolt  10   b.  The intermediate rotation member  6  is coaxially inserted and press-fitted into the driven side rotation member  2  to be positioned therein from a direction of a camshaft body  10   a.  The cylindrical rotation member  6  transmits the rotation of the driven side rotation member  2  to the OCV bolt  10   b.  The OCV bolt  10   b  is positioned between the driven side rotation member  2  and the intermediate rotation member  6  and screwed and fixed to an end portion of the camshaft body  10   a.  The intermediate rotation member  6  connects the driven side rotation member  2  and the camshaft  10 . The camshaft body  10   a  serves as a rotation shaft of a cam which controls, or regulates the opening and closing of the intake valve of the engine. The camshaft body  10   a  integrally rotates with the driven side rotation member  2 , the intermediate rotation member  6 , and the OCV bolt  10   b.  The camshaft body  10   a  is rotatably mounted to a cylinder head of the engine. 
     As shown in  FIG. 1 , the driving side rotation member  1  is integrally configured with a front plate  11 , an outer rotor  12  and a rear plate  13 . The front plate  11  is positioned on the opposite side of the camshaft body  10   a  relative to the intermediate rotation member  6 . The driven side rotation member  2  is covered by the outer rotor  12 . The rear plate  13  is integrally provided with a timing sprocket  15 . The driven side rotation member  2  is accommodated in the driving side rotation member  1  and a fluid pressure chamber  4  is defined between the driving side rotation member  1  and the driven side rotation member  2 . 
     When the crankshaft rotates, a rotational force is transmitted to the timing sprocket  15  via a force transmission member  100 . The driving side rotation member  1  rotates in a rotation direction S shown in  FIG. 2 . In response to the rotation of the driving side rotation member  1 , the driven side rotation member  2  is activated to rotate in the rotation direction S. Accordingly, the camshaft  10  rotates and the cam being provided at the camshaft body  10   a  pushes down the intake valve of the engine to open the valve. 
     As shown in  FIG. 2 , plural projections  14  is positioned inwardly of the outer rotor  12  and protrudes inwardly in a radial direction and being spaced apart along the rotation direction S. Thus, the fluid pressure chamber  4  is provided between the driven side rotation member  2  and the outer rotor  12 . The projection  14  functions as a shoe relative to an outer circumferential surface of the driven side rotation member  2 . Projections  21  are provided on the outer circumferential surface of the driven side rotation member  2  to be positioned at portions which face the fluid pressure chambers  4 , respectively. The fluid pressure chamber  4  is divided into an advanced angle chamber  41  serving as a fluid pressure chamber and a retarded angle chamber  42  serving as a fluid pressure chamber by the projection  21  along the rotation direction S. According to the embodiment, four fluid pressure chambers  4  are provided, however, the construction is not limited to the foregoing. 
     The oil serving as the operation fluid is supplied to and drained from the advanced angle chamber  41  and the retarded angle chamber  42 , or is blocked to be supplied to and drained from the advanced angle chamber  41  and the retarded angle chamber  42 , to apply the oil pressure to the projection  21 . Accordingly, the relative rotational phase of the driven side rotation member  2  relative to the driving side rotation member  1  is displaced in either the advanced angle direction or the retarded angle direction, or the relative rotational phase is maintained at a predetermined phase. The advanced angle direction is defined as a direction where the volume of the advanced angle chamber  41  increases and is indicated with an advanced angle direction S 1  (serving as a first rotation direction) in  FIG. 2 . The retarded angle direction is defined as a direction where the volume of the retarded angle chamber  42  increases and is indicated with a retarded angle direction S 2  (serving as a second rotation direction) in  FIG. 2 . The relative rotational phase when the volume of the advanced angle chamber  41  is maximized is defined as a most advanced angle phase. The relative rotational phase when the volume of the advanced angle chamber  42  is maximized is defined as a most retarded angle phase. 
     The variable valve timing control apparatus includes a lock mechanism  8  which locks, or retains the relative rotational phase of the driven side rotation member  2  relative to the driving side rotation member  1  at a predetermined lock phase which is positioned between the most advanced angle phase and the most retarded angle phase. In a state where the oil pressure is not stable immediately after starting the engine, the rotational phase of the camshaft  10  relative to the crankshaft may be maintained properly and the engine may rotate stably by locking, or retaining the relative rotational phase. 
     As shown in  FIG. 2 , a lock member  81  is movably configured along an axial direction. The lock member  81  is maintained in a locked state, or a retained state by being held in an engaged state with a lock groove provided at either the front plate  11  or the rear plate  13  by using a biasing member. A lock passage  82  is provided at the driven side rotation member  2  and connects the lock mechanism  8  and an advanced angle oil passage  43  (serving as a first flow path). When the advanced angle control is operated to displace the relative rotational phase of the driven side rotation member  2  relative to the driving side rotation member  1  to the advanced angle direction S 1 , the oil pressure is applied to the lock mechanism  8 . As a result, the lock member  81  comes out of the lock groove against the biasing force applied by the biasing member to release the locked state. 
     As shown in  FIG. 1 , the OCV  51  serves as a control valve and controls, or regulates a supply and draining of the oil to and from the fluid pressure chamber  4 . The OCV  51  is coaxially provided with the camshaft  10  and positioned inwardly of the intermediate rotation member  6  in the radial direction. The OCV  51  includes a spool  52 , a spring  53  which biases the spool  52 , and an electromagnetic solenoid  54  which activates the spool  52 . The spool  52  is accommodated in an accommodation space  5   a  which is provided at an end portion of the OCV bolt  10   b  and is slidable along an axis X inside the accommodation space  5   a.  The electromagnetic solenoid  54  adopts a known structure. 
     A spring  53  is provided inside the accommodation space  5   a  at a position which is axially inward of the accommodation space  5   a  and constantly biases the spool  52  in a direction opposite to the camshaft body  10   a.  Upon supplying electricity to the electromagnetic solenoid  54 , a push pin  54   a  provided at the electromagnetic solenoid  54  pushes a rod portion  52   a  which is provided at the spool  52 . In consequence, the spool  52  slides towards the camshaft body  10   a  against the biasing force of the spring  53 . The OCV  51  is configured to regulate, or control the position of the spool  52  by regulating, or controlling a duty ratio of the electric power supplied to the electromagnetic solenoid  54 . Further, the feeding amount by the OCV  51  to the electromagnetic solenoid  54  is controlled by an electric control unit, or an ECU. 
     As shown in  FIG. 5 , the cylindrical intermediate rotation member  6  is positioned inwardly of the driven side rotation member  2 , specifically, positioned at a portion closer to the cam shaft body  10   a  (the right in  FIG. 5 ). A washer member  7  is positioned inwardly of the driving side rotation member  1  and the driven side rotation member  2  and positioned opposite from the camshaft body  10   a  (the left in  FIG. 5 ) relative to the intermediate rotation member  6 . The intermediate rotation member  6  and the washer member  7  are positioned inwardly of the driven side rotation member  2 . As shown in  FIGS. 1 and 5 , in a state where the driven side rotation member  2  is covered by the driving side rotation member  1 , the OCV bolt  10   b  is placed inwardly of each center hole of the washer member  7 , the driven side rotation member  2  and the intermediate rotation member  6  and screwed and fixed to the camshaft body  10   a.  As shown in  FIG. 1 , the intermediate rotation member  6  and the driven side rotation member  2  are in contact with each other along the entire circumference in the axial direction between the advanced angle oil passage  43  and a retarded angle oil passage  44  (serving as a second flow path) and include a contact portion A. Thus, the intermediate rotation member  6  comes in contact with the driven side rotation member  2  at a position between the advanced angle oil passage  43  and the retarded angle oil passage  44  when mounting the intermediate rotation member  6  to the camshaft  10  after mounting the intermediate rotation member  6  and the driven side rotation member  2  to the driving side rotation member  1 . 
     The washer member  7  increases a tightening force of the OCV bolt  10  relative to the camshaft body  10   a.  A torsion spring  9  is mounted to position between the washer member  7  and the front plate  11  and biases the washer member  7  and the front plate  11  to rotate the driven side rotation member  2  relative to the driving side rotation member  1  in the advanced angle direction S 1 . 
     An outer diameter of the intermediate rotation member  6  is set to be slightly greater than an inner diameter of a cylindrical inner wall  2   a  (serving as an inner wall) of the driven side rotation member  2 . In a state where the intermediate rotation member  6  is inserted into the driven side rotation member  2  to be positioned inside thereof along the axis X, a fitting portion  20  fits the entire outer circumferential surface of the intermediate rotation member  6  into the entire inner circumferential surface of the cylindrical inner wall  2   a.  Accordingly, the intermediate rotation member  6  is integrally mounted to the driven side rotation member  2  by press-fitting into the driven side rotation member  2  at the fitting portion  20 . 
     A fitting pressure level of the fitting portion  20  to the driven side rotation member  2  is set to be a pressure level that allows the intermediate rotation member  6  to forcibly move to come in contact with the driven side rotation member  2  when the OCV bolt  10  which is inserted into and extends through the washer member  7 , the driven side rotation member  2 , and the intermediate rotation member  6  from a direction of the front plate  11  is screwed and fixed to the camshaft body  10   a.  Accordingly, the intermediate rotation member  6  reliably comes in contact with the driven side rotation member  2  throughout the circumference between the advanced angle oil passage  43  and the retarded angle oil passage  44  to prevent the oil from leaking out of and flowing into the advanced angle oil passage  43  and the retarded angle oil passage  44 . 
     When the driven side rotation member  2  and the intermediate rotation member  6  are mounted to the driving side rotation member  1 , a certain amount of a friction force is applied to the fitting portion  20  between the driven side rotation member  2  and the intermediate rotation member  6 . Then, the friction force serves as a resistance force and prevents the intermediate rotation member  6  from coming out of the driven side rotation member  2  until the camshaft  10  is connected to the intermediate rotation member  6  after mounting the intermediate rotation member  6  to the driven side rotation member  2 . 
     As shown in  FIG. 1 , the oil reserved in the oil pan  61  is sucked by a mechanical oil pump  62  that is actuated in response to the transmission of the rotational drive force of the crankshaft, and is supplied to an oil supply passage  45 . The OCV  51  controls the supplying and draining, or the blocking operation to supply and drain the oil to and from the advanced angle oil passage  43  and the retarded angle oil passage  44 . 
     The advanced angle oil passage  43  serves as an oil passage for changing the relative rotational phase of the driving side rotation member  1  and the driven side rotation member  2  in the advanced angle direction S 1 . The retarded angle oil passage  44  serves as an oil passage for changing the relative rotational phase of the driving side rotation member  1  and the driven side rotation member  2  in the retarded angle direction S 2 . Thus, the advanced angle oil passage  43 , the retarded angle oil passage  44  and a supply oil passage  45  correspond to flow paths which selectively supply and drain the oil to and from the fluid pressure chamber  4  in order to change the relative rotational phase of the driven side rotation member  2  relative to the driving side rotation member  1  between a most advanced angle phase and a most retarded angle phase. The advanced angle oil passage  43  corresponds to a first flow path and the retarded angle oil passage  44  corresponds to a second flow path. 
     As shown in  FIG. 1  and  FIG. 2 , the advanced angle oil passage  43  which communicates with the advanced angle chamber  41  is configured with a first through hole  43   a,  a first annular oil passage  43   b,  and a second through hole  43   c.  The first through hole  43   a  is provided at the OCV bolt  5   b.  The first annular oil passage  43   b  is positioned between the OCV bolt  5   b  and the driven side rotation member  2 . The second through hole  43   c  is provided at the driven side rotation member  2 . Thus, the space configuring the first annular oil passage  43   b  which corresponds to a part of the advanced angle oil passage  43  is defined between the driven side rotation member  2  and the OCV bolt  10   b.    
     The retarded angle oil passage  44  which communicates with the retarded angle chamber  42  is configured with a third through hole  44   a,  a second annular oil passage  44   b,  a fourth through hole  44   c,  and a fifth through hole  44   d.  The third through hole  44   a  is provided at the OCV bolt  5   b.  The second annular oil passage  44   b  is provided at an inner circumferential surface of the intermediate rotation member  6  between the OCV bolt  10   b  and the intermediate rotation member  6 . The fourth through hole  44   c  is provided at the intermediate rotation member  6 . The fifth through hole  44   d  is provided at the driven side rotation member  2 . Thus, the second annular oil passage  44   b  and the fourth through hole  44   c  which configure parts of the retarded angle oil passage  44  are provided at the intermediate rotation member  6 . 
     The oil supply passage  45  selectively supplying the oil to the advanced angle oil passage  43  and the retarded angle oil passage  44  is configured with a first passage  45   a,  a second passage  45   b,  a third annular passage  45   c,  and a sixth through hole  45   d.  The first passage  45   a  is provided at the camshaft body  10   a.  The second passage  45   b  is provided at the intermediate rotation member  6 . The third annular passage  45   c  is provided at the intermediate rotation member  6  between the intermediate rotation member  6  and the OCV bolt  10   b.  The sixth through hole  45   d  is provided at the OCV bolt  10   b.    
     Thus, the intermediate rotation member  6  includes the second annular oil passage  44   b,  the fourth though hole  44   c,  the second passage  45   b  and the third annular oil passage  45   c  which are the parts of the advanced angle oil passage  43 , the retarded angle oil passage  44 , and the supply oil passage  45  which supply and drain the oil to and from the fluid pressure chamber  4 . 
     As shown in  FIG. 1 , the oil which flows inside the supply oil passage  45  flows into an annular groove  52   b  which is provided at an outer circumferential surface of the spool  52 . In a state where the annular groove  52   b  communicates with neither the first through hole  43   a  nor the third through hole  44   a  which are provided at the OCV bolt  10   b,  the oil is not supplied to the advanced angle chamber  41  and the retarded angle chamber  42 . In this state, because the first through hole  43   a  is configured so as not to communicate with the seventh through hole  52   c  which is provided at the spool  52 , the oil in the advanced angle chamber  41  is not drained to the outside of the variable valve timing control device via the advanced angle oil passage  43 , the seventh through hole  52   c , the accommodation space  5   a  and a drain hole  52   d.  In addition, in this state, the third through hole  44   a  is configured so as not to communicate with the accommodation space  5   a,  the oil in the retarded angle chamber  42  is not drained to the outside of the variable valve timing control device via the retarded angle oil passage  44 , the accommodation space  5   a  and a drain hole  52   d.  That is, upon supplying a predetermined amount of electricity to the electromagnetic solenoid  54  to control the OCV  51  to hold the spool  52  at the position shown in  FIG. 1 , the relative rotational phase of the driven side rotation member  2  relative to the driving side rotation member  1  is maintained because the oil is blocked so as not to be supplied and drained to and from the advanced angle chamber  41  and the retarded angle chamber  42 . 
     When the electromagnetic solenoid  54  is not energized, the spool  52  is held at the position shown in  FIG. 3  by the biasing force of the spring  53 . In those circumstances, the annular groove  52   b  of the spool  52  communicates with the first through hole  43   a  of the OCV bolt  10   b  and does not communicate with the third through hole  44   a.  Simultaneously, the third through hole  44   a  communicates with the accommodation space  5   a.  Thus, the oil supplied to the supply oil passage  45  is supplied to the advanced angle chamber  41  via the advanced angle oil passage  43 , whereas the oil in the retarded angle chamber  42  is drained to the outside of the variable valve timing control device via the retarded angle oil passage  44 , the accommodation space  5   a,  and the drain hole  52   d . In those circumstances, the relative rotational phase is displaced in the advanced angle direction S 1  by the oil pressure applied to the advanced angle chamber  41 . 
     When the electromagnetic solenoid  54  is energized maximally, the spool  52  is held at the position shown in  FIG. 4  against the biasing force of the spring  53 . In those circumstances, the annular groove  52   b  of the spool  52  communicates with the third through hole  44   a  of the OCV bolt  10   b  and does not communicate with the first through hole  43   a.  Simultaneously, the first through hole  43   a  communicates with the seventh through hole  52   c  of the spool  52 . Thus, the oil supplied to the supply oil passage  45  is supplied to the retarded angle chamber  42  via the retarded angle oil passage  44 , whereas the oil in advanced angle chamber  41  is drained to the outside of the variable valve timing control device via the advanced angle oil passage  43 , the seventh through hole  52   c , the accommodation space  5   a,  and the drain hole  52   d.  In those circumstances, the relative rotational phase is displaced in the retarded angle direction S 2  by the oil pressure applied to the retarded angle chamber  42 . 
     A second embodiment of this disclosure will be explained referring to  FIG. 6 . In the second embodiment, the fitting portion  20  of the intermediate rotation member  6  is press-fitted to a portion of the cylindrical inner wall  2   a  along the direction of the axis X, specifically, only the portion positioned between a portion where the retarded angle oil passage  44  is formed and the contact portion A. The outer circumferential surface of the intermediate rotation member  6  protruding towards the rear plate  13  relative to the driven side rotation member  2  is relatively rotationally in close contact with the rear plate  13 . 
     That is, in a state where the fitting portion  20  press-fits only to the portion of the cylindrical inner wall  2   a  positioned between the portion where the retarded angle oil passage  44  is formed and the contact portion A, the intermediate rotation member  6  is in close contact with the driven side rotation member  2  at the fitting portion  20  and at the contact portion A. Accordingly, the advanced angle oil passage  43  and the retarded angle oil passage  44  are prevented from communicating with each other via the interface between the intermediate rotation member  6  and the driven side rotation member  2 . 
     On the other hand, in a state where the gap is generated between the outer circumferential surface of the intermediate rotation member  6 , specifically, a part protruding towards the rear plate  13  relative to the portion where the retarded angle oil passage  44  is formed, and the rear plate  13 , the oil may leak to the outside of the variable valve timing control device via the retarded angle oil passage  44  which extends over the intermediate rotation member  6  and the driven side rotation member  2 . Thus, the outer circumferential surface of the intermediate rotation member  6  is configured so as to be relatively rotationally in close contact with the rear plate  13  to prevent the oil from leaking out via the retarded angle oil passage  44 . Constructions other than the aforementioned configuration are similar to the constructions of first embodiment. 
     A third embodiment of this disclosure will be explained referring to  FIG. 7 . Similarly to  FIG. 6  showing the configuration of the second embodiment, according to the third embodiment, the outer circumferential surface of the intermediate rotation member  6 , specifically, the part protruding towards the rear plate  13  relative to the driven side rotation member  2  is relatively rotationally in close contact with the rear plate  13  to prevent the oil from leaking to the outside via the retarded angle oil passage  44 . In the third embodiment, plural fitting portions  200  which are formed on the outer circumferential surface of the intermediate rotation member  6  in order to be fitted to the cylindrical inner wall  2   a  of the driven side rotation member  2  are press-fitted to plural portions of the cylindrical inner wall  2   a,  the plural portions which are equally spaced apart along the circumferential surface of the cylindrical inner wall  2   a.    
     That is, press-fitting portions  20   a  include the same width and are equally spaced apart on the cylindrical inner wall  2   a  of the driven side rotation member  2  in a circumferential direction at, for example, three portions. A length from an inner surface of the press-fitting portions  20   a  to a center of the driven side rotation member  2  is shorter than a length from the cylindrical inner wall  2   a  to a center of the intermediate rotation member  6 . The intermediate rotation member  6  includes the fitting portions  200  which are equally spaced apart and press-fitted to the press-fitting portions  20   a.    
     According to the third embodiment, for example, three outer diameter portions  6   a  of the intermediate rotation member  6  are reliably press-fitted to the cylindrical inner wall  2   a.  Thus, the intermediate rotation member  6  is coaxially positioned with the driven side rotation member  2  precisely while reducing the size of the portion of the intermediate rotation member  6  to be processed for press-fitting. 
     Alternatively, the fitting portions  200  may include the plural press-fitting portions  20   a  which are unequally spaced apart on the cylindrical inner wall  2   a  in the circumferential direction. That is, according to the third embodiment, the driven side rotation member  2  includes the plural press-fitting portions  20   a  which are irregularly positioned along the circumferential direction of the driven side rotation member  2  and come in contact with the intermediate rotation member  6  when press-fitting to the intermediate rotation member  6 . A length from the press-fitting portion to a center of the driven side rotation member  2  is shorter than a length from the cylindrical inner wall  2   a  to a center of the driven side rotation member  2 . 
     Alternatively, according to the variable valve timing control device of the disclosure controls an opening and closing timing of an exhaust valve. 
     Alternatively, according to the variable valve timing control device of the disclosure is applicable to an internal combustion engine for an automobile and for other purposes. 
     According to the aforementioned embodiment, the variable valve timing control device includes the driving side rotation member ( 1 ) configured to synchronously rotate with the driving shaft of the internal combustion engine, the driven side rotation member ( 2 ) provided inwardly of the driving side rotation member ( 1 ) to be coaxial with the driving side rotation member ( 1 ), the driven side rotation member ( 2 ) integrally rotating with the camshaft ( 10 ) for opening and closing the valve of the internal combustion engine, the fluid pressure chamber ( 4 ,  41 ,  42 ) defined between the driving side rotation member ( 1 ) and the driven side rotation member ( 2 ), the first flow path (the advanced angle oil passage  43 ) and the second flow path (the retarded angle oil passage  44 ) allowing the flow of the operation fluid into and out of the fluid pressure chamber ( 4 ,  41 ,  42 ) to change the relative rotational phase of the driven side rotation member ( 2 ) relative to the driving side rotation member ( 1 ) between the most advanced angle phase and the most retarded angle phase, the intermediate member (the intermediate rotation member  6 ) being provided between the inner circumferential surface of the driven side rotation member ( 2 ) and the outer circumferential surface of the camshaft ( 10 ), the intermediate member (the intermediate rotation member  6 ) connecting the driven side rotation member ( 2 ) and the camshaft ( 10 ), and the contact portion (A) where the intermediate member (the intermediate rotation member  6 ) and the driven side rotation member ( 2 ) come in contact with each other at the position between the first flow path (the advanced angle oil passage  43 ) and the second flow path (the retarded angle oil passage  44 ) when mounting the intermediate member (the intermediate rotation member  6 ) to the camshaft ( 10 ) after mounting the intermediate member (the intermediate rotation member  6 ) and the driven side rotation member ( 2 ) to the driving side rotation member ( 1 ) after mounting the intermediate member (the intermediate rotation member  6 ) to the driven side rotation member ( 2 ) by press-fitting in a state where the space configuring the part of the first flow path (the advanced angle oil passage  43 ) is defined between the driven side rotation member ( 2 ) and the camshaft ( 10 ) and the intermediate member (the intermediate rotation member  6 ) includes the part of the second flow path (the retarded angle oil passage  44 ). 
     According to the aforementioned embodiment, the intermediate rotation member  6  comes in contact with the driven side rotation member  2  between the first flow path and the second flow path when the intermediate rotation member  6  is mounted to the camshaft  10  after the intermediate rotation member  6  and the driven side rotation member  2  are mounted to the driving side rotation member  1  after the intermediate rotation member  6  is press-fitted into the driven side rotation member  6 . Thus, when the intermediate rotation member  6  and the driven side rotation member  2  are mounted to the driving side rotation member  1 , the intermediate rotation member  6  is positioned inside the driven side rotation member  2  by press-fitting. Accordingly, without having to be glued by an adhesive material or attracted by a magnetic force of a magnet, the intermediate rotation member  6  is prevented from being coming out of the driven side rotation member  2  by the friction force applied between the driven side rotation member  2  and the intermediate rotation member  6  before mounting the driven side rotation member  2  and the intermediate rotation member  6  to the camshaft  10 . Thus, after mounting the driven side rotation member  2  and the intermediate rotation member  6  to the driving side rotation member  1 , the intermediate rotation member  6  is prevented from coming out of the driven side rotation member  2  before mounting the camshaft  10  to the intermediate rotation member  6 . 
     According to the variable valve timing control device of the embodiment, the driven side rotation member  2  is prevented from being damaged by the camshaft  10  which is made from the high-strength material. Along with that, the mounting process is simplified while adopting the construction where the operation fluid is prevented from leaking out of and flowing into the first and second flow paths. 
     According to the aforementioned embodiment, the variable valve timing control device further includes the control valve ( 51 ) being positioned inwardly of the intermediate member (the intermediate rotation member  6 ) in the radial direction, the control valve ( 51 ) controlling the operation fluid to flow into and out of the fluid pressure chamber ( 4 ,  41 ,  42 ). 
     According to the aforementioned configuration, comparing to a case where a control valve is positioned outside a camshaft, the flow path in which the operation fluid flows in and out of the fluid chamber is shortened. Accordingly, the OCV  51  may be mounted to a reduced space while reducing the process for configuring the flow path. 
     According to the aforementioned embodiment, the intermediate member (the intermediate rotation member  6 ) is press-fitted to the portion of an inner wall (cylindrical inner wall  2   a ) of the driven side rotation member ( 2 ). 
     According to the aforementioned configuration, the intermediate rotation member  6  may be processed with a reduced man-hour and a reduced size of the portion to be processed. 
     According to the aforementioned embodiment, the intermediate member (intermediate rotation member  6 ) is press-fitted to the inner wall (cylindrical inner wall  2   a ) of the driven side rotation member ( 2 ) at the plural positions being equally spaced apart along the circumferential direction relative to the axis (X). 
     According to the aforementioned configuration, the intermediate rotation member  6  may be processed with a reduced man-hour and a further reduced size of the portion to be processed. 
     According to the aforementioned embodiment, the intermediate member (intermediate rotation member  6 ) is fitted only to the portion positioned between the portion where the second flow path (the retarded angle oil passage  44 ) is formed and the contact portion (A) of the inner wall (cylindrical inner wall  2   a ). 
     According to the aforementioned configuration, the intermediate rotation member  6  may be processed with a reduced man-hour and a reduced size of the portion to be processed. 
     According to the aforementioned embodiment, the driven side rotation member ( 2 ) includes the plural press-fitting portions ( 20   a ) being irregularly positioned along the circumferential direction of the driven side rotation member ( 2 ), the plural press-fitting portions ( 20   a ) coming in contact with the intermediate member (intermediate rotation member  6 ) when press-fitting to the intermediate member (intermediate rotation member  6 ), and the length from the press-fitting portion to a center of the driven side rotation member  2  is shorter than the length from the inner wall (cylindrical inner wall  2   a ) to a center of the driven side rotation member ( 2 ). 
     According to the aforementioned configuration, the intermediate rotation member  6  may be processed with a reduced man-hour and a further reduced size of the portion to be processed. 
     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.