Valve opening/closing timing control device, and production method for drive side rotational body of valve opening/closing timing control device

Abstract

A valve opening/closing timing control device includes a housing main body that includes an opening which opens to at least one side in a direction along a rotational axis and a cover plate closing the opening by making contact with an end surface of the opening, the drive side rotational body rotating synchronously with a crankshaft, and a driven side rotational body housed within the drive-side rotational body and defining an advance chamber and a retardation chamber relative to an inner peripheral surface of the housing main body, the driven-side rotational body rotating integrally with a camshaft and coaxially with the rotational axis. In addition, the housing main body includes a hard layer formed at least at the inner peripheral surface of the housing main body in a surface thereof excluding the end surface of the opening.

1 . A valve opening/closing timing control device comprising:
 a drive side rotational body including a housing main body that includes an opening which opens to at least one side in a direction along a rotational axis and a cover plate closing the opening by making contact with an end surface of the opening, the drive side rotational body rotating synchronously with a crankshaft; and   a driven side rotational body housed within the drive side rotational body and defining an advance chamber and a retardation chamber relative to an inner peripheral surface of the housing main body, the driven side rotational body rotating integrally with a camshaft and coaxially with the rotational axis, wherein   the housing main body includes a hard layer formed at least at the inner peripheral surface of the housing main body in a surface thereof excluding the end surface of the opening.   
     
     
         2 . The valve opening/closing timing control device according to  claim 1 , wherein the housing main body is in an annular form and the hard layer at the inner peripheral surface is formed up to the same position as the end surface of the opening in an axis direction of the housing main body. 
     
     
         3 . A production method for a drive side rotational body of a valve opening/closing timing control device, the valve opening/closing timing control device including:
 a drive side rotational body including at least one housing main body that includes an opening which opens to at least one side in a direction along a rotational axis and a cover plate closing the opening by making contact with an end surface of the opening, the drive side rotational body rotating synchronously with a crankshaft; and   a driven side rotational body housed within the drive side rotational body and defining an advance chamber and a retardation chamber relative to an inner peripheral surface of the housing main body, the driven side rotational body rotating integrally with a camshaft and coaxially with the rotational axis,   
       the production method comprising forming a hard layer at least at the inner peripheral surface of the housing main body in a region thereof excluding the end surface of the opening. 
     
     
         4 . The production method for the drive side rotational body according to  claim 3 , wherein
 the housing main body is made of an aluminum material and the end surface of the opening of the housing main body is covered by a rubber member constituted by at least two types of rubber materials including different hardness,   the rubber material including a high hardness in the rubber member is disposed at a portion making contact with an edge portion of the end surface of the opening in a vicinity of the inner peripheral surface of the housing main body among edge portions of the end surface of the opening.   
     
     
         5 . The production method for the drive side rotational body according to  claim 3 , wherein the hard layer is formed at least at an inner peripheral surface of a cylinder body among the inner peripheral surface and an outer peripheral surface of the cylinder body,
 the cylinder body is cut along a cutting-plane line which is specified at the outer peripheral surface depending on a thickness dimension of the housing main body to form the drive side rotational body.