[A study on noise controlling of the electromagnetic valve in external counterpulsation devices]

Noise of ECP (external counterpulsation) comes from the frequent movement of the electromagnetic valve iron core hitting the top of the valve body and the orifice of the bottom, and the high pressure and large air stream rubbing the orifice. This article studies the method to reduce mechanical noise of the electromagnetic valve core, that is to reduce the above movement energy and the hitting force. The method is used in ECP devices with grafying results. This noise controlling technology may reduce the noise of the electromagnetic valve from higher than 50dB to less than 25dB.