Valve timing adjusting apparatus

Abstract

A valve timing adjusting apparatus includes a housing, a vane rotor, at least one shaft member, and at least one annular seal member. The at least one shaft member is rotatable synchronously with a driven-side shaft and the vane rotor, and is journaled within the housing. The at least one annular seal member is provided between the at least one shaft member and the housing, and the at least one seal member limits leakage of working fluid from a receiving chamber of the housing to an exterior of the housing.

1 . A valve timing adjusting apparatus mounted on a driving force transmission system that transmits driving force from a driving-side shaft of an internal combustion engine to a driven-side shaft for opening and closing at least one of intake and exhaust valves, wherein the valve timing adjusting apparatus adjusts timing of opening and closing the at least one of the intake and exhaust valves, the valve timing adjusting apparatus comprising:
 a housing that is rotatable synchronously with the driving-side shaft, wherein the housing defines a receiving chamber in a predetermined angular range in a rotational direction;   a vane rotor that is rotatable synchronously with the driven-side shaft, wherein:
 the vane rotor sections the receiving chamber into a retard chamber and an advance chamber; and 
 the vane rotor is rotatable with respect to the housing in a retard direction or in an advance direction based on pressure of working fluid that is supplied to the retard chamber and the advance chamber; 
   at least one shaft member that is provided on at least one of a first side of the vane rotor toward the driven-side shaft and a second side of the vane rotor opposite from the first side, wherein:
 the at least one shaft member is rotatable synchronously with the driven-side shaft and the vane rotor; and 
 the at least one shaft member is journaled within the housing; and 
   at least one annular seal member that is provided between the at least one shaft member and the housing, wherein the at least one seal member limits leakage of working fluid from the receiving chamber to an exterior of the housing.   
   
   
       2 . The valve timing adjusting apparatus according to  claim 1 , wherein:
 the housing includes an annular groove defined at an inner peripheral wall of the housing;   the at least one seal member has an outer peripheral edge portion received by the groove of the housing; and   the at least one seal member has an inner peripheral wall that fluid-tightly contacts an outer peripheral wall of the at least one shaft member over an entire perimeter of the at least one shaft member.   
   
   
       3 . The valve timing adjusting apparatus according to  claim 1  wherein:
 the at least one shaft member includes an annular groove defined at an outer peripheral wall of the at least one shaft member;   the at least one seal member has an inner peripheral edge portion received by the groove of the at least one shaft member; and   the at least one seal member has an outer peripheral wall that fluid-tightly contacts an inner peripheral wall of the housing over an entire perimeter of the housing.   
   
   
       4 . The valve timing adjusting apparatus according to  claim 2 , wherein;
 the groove of the housing has a dimension of D in a radial direction of the groove;   the at least one seal member has a dimension of W in a radial direction of the at least one seal member;   the housing and the at least one shaft member define therebetween a clearance having a maximum dimension of C measured in a radial direction of the at least one shaft member; and   C<W≦D is satisfied.   
   
   
       5 . The valve timing adjusting apparatus according to  claim 3 , wherein:
 the groove of the at least one shaft member has a dimension of D in a radial direction of the groove;   the at least one seal member has a dimension of W in a radial direction of the at least one seal member;   the housing and the at least one shaft member define therebetween a clearance having a maximum dimension of C measured in a radial direction of the at least one shaft member; and   C<W≦D is satisfied.