Abstract: A lash adjuster is provided which includes a cylindrical housing having an open top and formed with an internal thread on an inner periphery thereof, a screw rod having an external thread formed on an outer periphery thereof and in threaded engagement with the internal thread, and a spring biasing the screw rod outwardly of the housing. Each of the internal thread and the external thread having a pressure flank configured to receive pressure when a force that tends to push the screw rod into the housing acts on the screw rod, and a clearance flank having a smaller flank angle than the pressure flank. The screw rod has an end protruding from the housing and configured to support an arm of a valve operating mechanism so as to be pivotable about this end. Oil film expelling grooves are formed in the pressure flank of the external thread, using a tap having a thread that extends so as to cross the internal thread.

Abstract: A lash adjuster is provided which includes a cylindrical housing having an open top and formed with an internal thread on an inner periphery thereof, a screw rod having an external thread formed on an outer periphery thereof and in threaded engagement with the internal thread, and a spring biasing the screw rod outwardly of the housing. Each of the internal thread and the external thread having a pressure flank configured to receive pressure when a force that tends to push the screw rod into the housing acts on the screw rod, and a clearance flank having a smaller flank angle than the pressure flan. The screw rod has an end protruding from the housing and configured to support an arm of a valve operating mechanism so as to be pivotable about this end. Oil film expelling grooves are formed in the pressure flank of the external thread, using a tap having a thread that extends so as to cross the internal thread.

Abstract: A rotation transmission device includes a roller clutch unit for selectively engaging an inner member mounted on a rotary shaft with an outer ring through rollers, and an electromagnetic clutch unit for electromagnetically controlling the selective engagement by the rollers. The current until the clutch engages is set so as to correspond to a state in which a maximum current according to the revolving speed is required and is varied according to the revolving speed of the rotary shaft to reduce power consumption and the size of the electromagnetic coil.

Abstract: An object is to provide a rotation transmission device in which a current is applied to an electromagnetic coil to selectively engage a roller clutch, and in which the current applied to the electromagnetic clutch is controlled based on the revolving speed of a rotary shaft to reduce power consumption and the size of the electromagnetic coil. The rotation transmission device C1 includes a roller clutch unit 10 for selectively engaging an inner member 11 mounted on the rotary shaft with an outer ring 14 through rollers 13, and an electromagnetic clutch unit 20 for electromagnetically controlling the selective engagement by the rollers 13. The current until the clutch engages is set so as to correspond to a state in which a maximum current according to the revolving speed is required and is varied according to the revolving speed of the rotary shaft to reduce power consumption and the size of the electromagnetic coil 21.

Abstract: A rotation transmission device includes an input member, an outer ring mounted around the input member, a two-way clutch and an electromagnetic clutch for selectively engaging and disengaging the two-way clutch, both clutches being mounted between the input member and the outer ring. The electromagnetic clutch includes an armature coupled to a retainer of the two-way clutch so as to be non-rotatable and axially movable relative to the retainer. By energizing its electromagnet, the armature is pulled toward the electromagnet until it is pressed against a rotor fixed to the outer ring. The input member is formed with an oil supply passage. Oil is supplied through the oil supply passage and an oil passage defined between the outer periphery of the input member and the inner periphery of the rotor into a space between the two clutches. The oil passage has a restricted, narrow portion to limit the amount of oil supplied into the above space.

Abstract: A rotation transmission device includes an input member, an outer ring mounted around the input member, a two-way clutch and an electromagnetic clutch for selectively engaging and disengaging the two-way clutch, both clutches being mounted between the input member and the outer ring. The electromagnetic clutch includes an armature coupled to a retainer of the two-way clutch so as to be non-rotatable and axially movable relative to the retainer. By energizing its electromagnet, the armature is pulled toward the electromagnet until it is pressed against a rotor fixed to the outer ring. The input member is formed with an oil supply passage. Oil is supplied through the oil supply passage and an oil passage defined between the outer periphery of the input member and the inner periphery of the rotor into a space between the two clutches. The oil passage has a restricted, narrow portion to limit the amount of oil supplied into the above space.