Abstract: A low speed cam is disposed on a cam shaft. A low speed sub-rocker arm actuated by the low speed cam is pivotally connected to a main rocker arm. A connecting member is supported by the main rocker arm. The connecting member has both a first condition wherein the sub-rocker arm and the main rocker arm are fixed to each other to constitute a single unit and a second condition wherein the sub-rocker arm and the main rocker arm are disengaged from each other. A hydraulically actuating mechanism has a hydraulic work chamber. The mechanism induces the first condition of the connecting member upon discharge of hydraulic fluid from the work chamber and induces the second condition upon feeding of hydraulic fluid to the work chamber. A control unit causes the hydraulically actuating mechanism to induce the first condition of the connecting member when the engine stops.

Abstract: A variable valve actuation apparatus for engine cylinder valves comprises a main rocker arm having an end portion for driving association with a cylinder valve. The main rocker arm supports a sub-rocker arm. A lost motion mechanism is between the main rocker and sub-rocker arms. The main rocker arm is formed with a plunger seat. The plunger seat includes a bearing surface on which a plunger of the lost motion mechanism rests. Further, the plunger seat includes gutters for discharging lubricant oil.

Abstract: An cylinder valve controlling apparatus comprises a first rocker arm and a second rocker arm cooperating with a middle lift cam and a low lift cam, respectively, to active two cylinder valves arranged for each of the engine cylinders, respectively. The apparatus further comprises a free rocker arm cooperating with a high lift cam. During engine operation at low speeds, the first rocker arm activates one of the cylinder valves in accordance with the profile of the middle lift cam, while the second rocker arm activates the other cylinder valve in accordance with the profile of the low lift cam. During engine operation at middle speeds, a coupling including a first lever establish drive connection between the first and second rocker arms and thus the first and second rocker arms follow the profile of the middle cam.

Abstract: A valve lifter and processing method therefor include a valve lifter surface to be installed in a recess of a cylinder head of an internal combustion engine. The method includes a grinding step for beveling, or tapering, the circumferential end of a cylindrical wall portion of the valve lifter which slidingly contacts the recess. Excess material resulting from the beveling process is then removed for smoothing the beveled circumferential end. The smoothed surface is then coated with a hardening layer for abrasion protection and smoother operational movement. As a final step, the hardening layer may be polished for further enhancement of operating performance.

Abstract: A video signal recording/reproducing apparatus includes a recording medium having a video track and an audio track separately formed, wherein a video signal is recorded in the video track and an audio signal to be multiplexed and a discrimination signal of a low frequency and a low level representing the kind of multiplexing thereof are recorded in the audio track. Decision is made of the kind of multiplexing of the audio signal, such as a bilingual mode, a stereo mode or a monaural mode, as recorded in the audio track, in response to the descrimination signal reproduced from the audio track and a multiplexed audio signal is produced in response to the decision signal representing the kind of the audio signal and the audio signal reproduced from the audio track.