Method of setting tappet clearance and device therefor
AssigneeHonda Motor Co., Ltd.
InventorNaoya Tanuma
Life of this patent
Estimating the term…
Abstract
Even in the case where, due to distortion (undulation) or the like of an end surface of an adjusting screw abutting on a valve stem end, there exists a non-linear undulation movement amount in a movement amount of the end surface with respect to a rotation return angle of the adjusting screw, the undulation movement amount is continuously measured, and a screw return movement amount based on a screw pitch and on the rotation return angle is continuously calculated, and, when a total movement amount of the undulation movement amount and the screw return movement amount has attained a prescribed clearance, return rotation is ended.
Claims9
A method of setting tappet clearance by which a tappet clearance between an end surface of an adjusting screw screwed into an acting end of a rocker arm, and a valve stem end, is set to a prescribed clearance, the method comprising:
- a step of starting return rotation of the adjusting screw from a position where the end surface of the adjusting screw is abutting on the valve stem end due to weight of the rocker arm on an acting end side, and a pressing torque on the valve stem end has a zero value, the return rotation being started in a state where the abutting is being continued;
- a step of, when rotation is being returned in the state where the abutting is being continued, continuously measuring, as an undulation movement amount, movement of the end surface of the adjusting screw in both directions in an axial direction of the adjusting screw due to undulation, and continuously calculating, as a screw return movement amount, movement based on a screw pitch in a return direction in the axial direction of the adjusting screw and on a rotation return angle;
- and
- a step of ending the return rotation of the adjusting screw when a total movement amount of the undulation movement amount and the screw return movement amount that have been continuously acquired has attained the prescribed clearance.
A device that sets tappet clearance by which a tappet clearance between an end surface of an adjusting screw screwed into an acting end of a rocker arm, and a valve stem end, is set to a prescribed clearance, the device comprising:
- a screwdriver configured to rotate the adjusting screw;
- a return rotation starting unit configured to start return rotation of the adjusting screw by the screwdriver, from a position where the end surface of the adjusting screw is abutting on the valve stem end due to weight of the rocker arm on an acting end side, and a pressing torque on the valve stem end has a zero value, the return rotation being started in a state where the abutting is being continued;
- a measuring unit configured to, when rotation is being returned in the state where the abutting is being continued, continuously measure, as an undulation movement amount, movement of the end surface of the adjusting screw in both directions in an axial direction of the adjusting screw due to undulation;
- a return movement amount calculating unit configured to continuously calculate, as a screw return movement amount, movement based on a screw pitch in a return direction in the axial direction of the adjusting screw and on a rotation return angle;
- and
- a return rotation ending unit configured to end the return rotation of the adjusting screw when a total movement amount of the undulation movement amount and the screw return movement amount that have been continuously acquired has attained the prescribed clearance.
Dependencies are inferred from the claim text.