Semi-commanded valve system applied to compressor and method for modulating the capacity of a compressor provided with a semi-commanded valve system

1. A semi-commanded valve system applied to a compressor, wherein the compressor comprises at least a cylinder, at least a piston, at least a compression-chamber, and at least one prestressed valve acting in a respective orifice, the semi-commanded valve system comprising:

the at least one prestressed valve in an open operational state, and comprising at least a ferrous portion; and

at least one selectively actuated magnetic field generating element aligned with the at least one prestressed valve;

wherein the open operational state of the at least one prestressed valve is configured to be selectively switched by actuating the at least one selectively actuated magnetic field generating element, wherein the at least one selectively actuated magnetic field generating element, when activated, is configured to attract the at least one prestressed valve towards the at least one selectively actuated magnetic field generating element based upon the alignment to put the at least one prestressed valve in a closed operational state;

wherein when the piston starts from a lower dead point and travels towards to a superior dead point, pressure within the cylinder increases until it becomes higher than a pressure in a discharge chamber, and, at this time, the at least one prestressed valve begins an opening movement, which is facilitated by open prestress of said at least one prestressed valve;

wherein when the piston discharges a gas to an outside of the cylinder, a return to the lower dead point begins, and the at least one prestressed valve with open prestress remains opened to allow for the gas of the discharge chamber to return into the cylinder; and

wherein this return of gas of the discharge chamber into the cylinder stops when the at least one selectively actuated magnetic field generating element is driven, thereby closing said at least one prestressed valve.

2. The semi-commanded valve system, in accordance with claim 1 , wherein the at least one prestressed valve is configured to be selectively switched between the open operational state and the closed operational state using at least one magnetic pulse of the at least one selectively actuated magnetic field generating element.

3. The semi-commanded valve system, in accordance with claim 2 , wherein the open operational state of the at least one prestressed valve opens the respective orifice.

4. The semi-commanded valve system, in accordance with claim 2 , wherein the closed operational state of the at least one prestressed valve closes the respective orifice.

5. The semi-commanded valve system, in accordance with claim 1 , wherein the at least one prestressed valve comprises a suction valve.

6. The semi-commanded valve system, in accordance with claim 1 , wherein the at least one prestressed valve comprises a discharge valve.

7. The semi-commanded valve system, in accordance with claim 1 , wherein the at least one selectively actuated magnetic field generating element comprises an electric coil.

8. The semi-commanded valve system, in accordance with claim 1 , wherein the at least one prestressed valve and a respective selectively actuated magnetic field generating element of the at least one selectively actuated magnetic field generating element are disposed on at least a valve plate.

9. The semi-commanded valve system, in accordance with claim 1 , wherein the at least one prestressed valve includes two prestressed valves, and wherein a magnetic insulation is provided between the two prestressed valves.

10. A method for modulating the capacity of the compressor provided with the semi-commanded valve system as defined in claim 1 , comprising refluxing at least one of suction and exhaustion by non-spontaneous switching of the at least one prestressed valve.

11. The method, in accordance with claim 10 , further comprising delaying spontaneous closing of the at least one prestressed valve.

12. The method, in accordance with claim 10 , further comprising delaying spontaneous opening of the at least one prestressed valve.