Valve timing control device for internal combustion engine and method for attaching valve timing control device

Abstract

It includes: a housing (7) to which a torque is transmitted from a crankshaft; a vane rotor (8) mounted inside the housing and includes a cylindrical rotor (20) fastened to a camshaft (2) by a cam bolt (5); and a groove portion (47) formed at a distal end surface of a tubular part (23) of the rotor and has a lateral surface (47a) in a direction opposite to a direction of fastening of the cam bolt. The lateral surface includes an inside edge (47d) in a radial direction of the rotor, and is inclined in the direction opposite to the direction of fastening of the cam bolt, with respect to a first imaginary plane (S1) containing the inside edge and a rotational axis (O) of the vane rotor. This serves to suppress rotation of the vane rotor during bolting the vane rotor to the camshaft, and suppress deformation due to the suppression of rotation.

1 . An internal combustion engine valve timing control device comprising:
 a housing configured to receive a torque transmitted from a crankshaft;   a vane rotor mounted inside the housing, and including a rotor, wherein the rotor has a cylindrical shape, and is configured to be fastened to a camshaft by a cam bolt; and   a groove portion formed at an end surface of the rotor farther from the camshaft, and including a first lateral surface, wherein the first lateral surface is at a side of the groove portion in a direction opposite to a direction of fastening of the cam bolt;   wherein the first lateral surface includes an inside edge and an outside edge in a radial direction of the rotor, wherein the outside edge is in the direction opposite to the direction of fastening of the cam bolt, with respect to a first imaginary plane, wherein the inside edge and a rotational axis of the vane rotor are on the first imaginary plane.   
     
     
         2 . The internal combustion engine valve timing control device as claimed in  claim 1 , wherein:
 the vane rotor includes a tubular part at an end portion of the vane rotor farther form the camshaft, wherein the tubular part has a cylindrical shape projecting out of the housing; and   the groove portion is formed in the tubular part.   
     
     
         3 . The internal combustion engine valve timing control device as claimed in  claim 2 , further comprising a biasing member disposed between the tubular part and the housing, wherein:
 the biasing member includes a first end portion engaging with the tubular part, and a second end portion engaging with the housing, and is configured to bias the vane rotor in a first rotational direction with respect to the housing;   each of a plurality of portions of the tubular part arranged in a circumferential direction of the tubular part is formed with the groove portion; and   a portion of the tubular part between specific adjacent two of the groove portions is formed with an engaging groove, wherein the first end portion of the biasing member engages with the engaging groove.   
     
     
         4 . The internal combustion engine valve timing control device as claimed in  claim 3 , wherein the engaging groove is in the direction opposite to the direction of fastening of the cam bolt, with respect to an intermediate position between the specific adjacent two of the groove portions in the circumferential direction of the tubular part. 
     
     
         5 . The internal combustion engine valve timing control device as claimed in  claim 2 , wherein:
 the groove portion includes a second lateral surface opposite to the first lateral surface; and   the second lateral surface includes an inside edge and an outside edge in a radial direction of the tubular part, wherein the outside edge of the second lateral surface is in the direction of fastening of the cam bolt with respect to a second imaginary plane, wherein the inside edge of the second lateral surface and the rotational axis of the vane rotor are on the second imaginary plane.   
     
     
         6 . The internal combustion engine valve timing control device as claimed in  claim 2 , wherein:
 the groove portion includes a second lateral surface opposite to the first lateral surface; and   the second lateral surface includes an inside edge and an outside edge in a radial direction of the tubular part, wherein the outside edge of the second lateral surface is in the direction opposite to the direction of fastening of the cam bolt, with respect to a second imaginary plane, wherein the inside edge of the second lateral surface and the rotational axis of the vane rotor are on the second imaginary plane.   
     
     
         7 . The internal combustion engine valve timing control device as claimed in  claim 2 , wherein the tubular part is formed by sintering integrally with the rotor. 
     
     
         8 . An internal combustion engine valve timing control device comprising:
 a housing configured to receive a torque transmitted from a crankshaft, the housing including an operating chamber formed inside the housing;   a vane rotor mounted inside the housing, and including a rotor and a vane, wherein the rotor has a cylindrical shape, and is configured to be fastened to a camshaft by a cam bolt, and wherein the vane separates the operating chamber into a retard operation chamber and an advance operation chamber;   an extension part formed at an end portion of the rotor farther form the camshaft, the extension part projecting out of the housing;   a biasing member disposed between the extension part and the housing, wherein the biasing member includes a first end portion engaging with the extension part, and a second end portion engaging with the housing, and is configured to bias the vane rotor in a first rotational direction with respect to the housing; and   a groove portion formed at a distal end portion of the extension part, and including a first contact surface, wherein the first contact surface is configured to be in contact with a retaining tool for restricting rotation of the rotor during fastening of the cam bolt;   wherein the first contact surface is formed such that a vector of load from the retaining tool on the first contact surface during restriction of rotation of the rotor has an inward component in a radial direction of the rotor.   
     
     
         9 . An internal combustion engine valve timing control device comprising:
 a housing configured to receive a torque transmitted from a crankshaft, the housing including an operating chamber formed inside the housing;   a vane rotor mounted inside the housing, and including a rotor and a vane, wherein the rotor has a cylindrical shape, and is configured to be fastened to a camshaft by a cam bolt, and wherein the vane separates the operating chamber into a retard operation chamber and an advance operation chamber; and   a projecting part formed at an end surface of the rotor farther form the camshaft;   wherein the projecting part includes a first lateral surface, wherein the first lateral surface is at a portion of the projecting part in a direction of fastening of the cam bolt; and   wherein the first lateral surface includes an inside edge in a radial direction of the rotor, and is inclined in a direction opposite to the direction of fastening of the cam bolt, with respect to a first imaginary plane, wherein the inside edge and a rotational axis of the vane rotor are on the first imaginary plane.   
     
     
         10 . A method for attaching an internal combustion engine valve timing control device, wherein the internal combustion engine valve timing control device comprising:
 a housing configured to receive a torque transmitted from a crankshaft, the housing including an operating chamber formed inside the housing;   a vane rotor mounted inside the housing, and including a rotor and a vane, wherein the rotor has a cylindrical shape, and is configured to be fastened to a camshaft by a cam bolt, and wherein the vane separates the operating chamber into a retard operation chamber and an advance operation chamber; and   a tool engagement portion formed at an end surface of the rotor farther from the camshaft, and including a first lateral surface facing in a direction of fastening of the cam bolt;   wherein the first lateral surface includes an inside edge in a radial direction of the rotor, and is inclined in a direction opposite to the direction of fastening of the cam bolt, with respect to a first imaginary plane, wherein the inside edge and a rotational axis of the vane rotor are on the first imaginary plane;   the method comprising:   an operation of bringing an end surface of the rotor into contact with an end surface of the camshaft;   an operation of engaging a retaining tool into the tool engagement portion, wherein the retaining tool includes an engaging projection and a hole, wherein the engaging projection is configured to engage into the tool engagement portion, and wherein the hole of the retaining tool is configured to receive insertion of a fastening tool for fastening of the cam bolt; and   an operation of inserting the fastening tool through the hole of the retaining tool, and fastening the cam bolt by the fastening tool, while restricting rotation of the retaining tool.