Fig. 2.59. Electromagnetic valve of the VAD system: 1 – food is included; 2 – food is switched off; 3 – channel A (to the atmosphere); 4 – channel B (on the executive mechanism); 5 – channel C (to an inlet collector); 6 – spiral; 7 – plunger; 8 – spring

The electromagnetic valve changes the channel of vacuum of an inlet collector between an inlet collector and the executive mechanism. When food is included, the plunger of the valve is delayed and opens pass between air channels A and B which opens access to atmospheric air to the executive mechanism of the gate. When food is switched off, the plunger comes back forward and opens pass between air channels B and C which opens access to vacuum from an inlet collector to the executive mechanism of the gate. The electromagnetic valve consists of the solenoid, a spring, a plunger and the filter (fig. 2.59).