Japanese Piston Ring push continuously variable valve actuator
At the 39th Tokyo Motor Show, Japan Piston Ring showcased its innovative "Continuous Variable Valve Actuator (CVVA)" system, designed to continuously and precisely control the engine's intake process. This technology is expected to significantly reduce pump losses and enhance fuel efficiency. In traditional engines, throttle bodies are used to regulate the intake and exhaust valve timing. However, this method can lead to inefficiencies—when the throttle closes at low speeds, it restricts air intake, creating a vacuum in the intake manifold that causes resistance and energy loss, known as pump loss.
The CVVA system eliminates the need for a traditional throttle by directly controlling the valve lift through a mechanical linkage. The system uses two swing arms connected to the suction cam and an accelerator. A lever is attached to the second swing arm, allowing the tip of the lever to rotate and adjust the pivot point of the arm. This adjustment controls the valve lift, enabling the engine to optimize air intake based on operating conditions. At low speeds, the valve lift is reduced to minimize air intake, while at high speeds, the lift increases to maximize airflow.
The lever mechanism is driven by an actuator that utilizes a ball screw system powered by a rotary motor. According to the company, for inline engines with multiple cylinders, a single actuator can control all the levers, improving efficiency and reducing complexity. However, the system is not yet compact enough to be directly integrated into the engine, and further miniaturization is needed before it can be widely adopted. This innovation represents a promising step toward more efficient and responsive engine technologies.
ZHENAN NEW METAL CO .,LTD , https://www.zanewmaterial.com