Vibratory system comprising shaft lines, and a corresponding machine and method

1. A vibratory system for a screening and/or feeder machine, the vibratory system comprising:

a plurality of shaft lines, each shaft line having an unbalance module;

a drive device configured to drive the shaft lines in rotation in synchronous manner and in the same direction;

an angle modifier device configured to modify the angular position of the unbalance module of a first one shaft line of the plurality of shaft lines relative to the angular position of the unbalance module of a second shaft line of the plurality of shaft lines, the unbalance modules being capable of taking up a relative first angular position, in which the unbalance modules are in phase and a relative second angular position, in which the unbalance modules are in phase opposition;

a control unit configured to control the drive device and the angle modifier device, said control unit including a processor and computer instructions which, when executed by the processor, causes the processor to:

prior to driving the shaft lines in rotation by means of the drive device, bring the unbalance modules into phase opposition;

drive the shaft lines in rotation by means of the drive device;

keep the unbalance modules of the shaft lines in phase opposition until the unbalance modules have reached a given operating speed;

after said given speed of rotation has been reached for the shaft lines, bring the unbalance modules in phase;

prior stopping rotary drive of the shaft lines, bring the unbalance modules into phase opposition; and

stop the rotary drive of the shaft lines when said unbalance modules have been brought into phase opposition.

2. The vibratory system according to claim 1 , wherein the drive device comprises:

a main motor configured to drive one of the plurality of shaft lines in rotation; and

a synchronous transmission mechanism configured to transmit rotation from the shaft line driven by the main motor to another shaft line so that the plurality of shaft lines rotate in synchronous manner and in the same direction.

3. The vibratory system according to claim 1 , wherein the control unit further includes computer instructions which, when executed by the processor, causes the processor to: while the shaft lines are being driven in rotation by the drive device, modify the amplitude of the vibration by modifying the angular position of the unbalance module of one shaft line relative to the angular position of the unbalance module of another shaft line.

4. The vibratory system according to claim 1 , wherein the control unit further includes computer instructions which, when executed by the processor, causes the processor to: when rotation of the shaft lines is stopped, bring the unbalance modules in phase and into a low position.

5. A screening and/or feeder vibrator machine including a vibratory system and wherein the vibratory system is in accordance with claim 1 .

6. A vibratory system for a screening and/or feeder machine, the vibratory system comprising:

a plurality of shaft lines, each shaft line having an unbalance module;

a drive device configured to drive the shaft lines in rotation in synchronous manner and in the same direction;

an angle modifier device configured to modify the angular position of the unbalance module of a first one shaft line of the plurality of shaft lines relative to the angular position of the unbalance module of a second shaft line of the plurality of shaft lines, the unbalance modules being capable of taking up a relative first angular position, in which the set of unbalance modules presents a static moment of a first value, wherein the angle modifier device comprises an adjustment motor and an epicyclic gear train, the epicyclic gear train comprising a sun gear connected to the outlet shaft of the adjustment motor, a toothed ring connected to one of the shaft lines, and planets mounted to mesh with the toothed ring and with the sun gear, the angle modifier device also comprising a planet carrier that carries the planets and that is coupled to rotate with the other shaft line

a control unit configured to control the drive device and the angle modifier device, said control unit including a processor and computer instructions which, when executed by the processor, causes the processor to, prior stopping rotary drive of the shaft lines:

bring the unbalance modules into a second angular configuration in which the set of unbalance modules presents a static moment having a second value smaller than said first value; and

stop the rotary drive of the shaft lines when said unbalance modules have been brought into the second angular configuration.

7. The vibratory system according to claim 6 , wherein the adjustment motor is configured in such a manner that its outlet shaft is suitable firstly for rotating in one direction in order to modify the angular position of an unbalance module, and secondly for preventing rotation in the opposite direction.

8. A method of controlling a vibratory system including a plurality of shaft lines each including an unbalance module, wherein said method comprises the steps of:

providing a drive device configured to drive the plurality of shaft lines in rotation in synchronous manner and in the same direction;

providing an angle modifier device configured to modify an angular position of the unbalance module of a first one shaft line of the plurality of shaft lines relative to an angular position of the unbalance module of a second shaft line of the plurality of shaft lines, the unbalance modules being capable of taking up a relative first angular position in which the unbalance modules are in phase and a relative second angular position in which the unbalance modules are in phase opposition;

providing a control unit configured to control the drive device and the angle modifier device;

prior to operating the drive device to rotate the plurality of shaft lines, bringing the unbalance modules into the relative second angular position in which the unbalance modules are in phase opposition;

operating the drive device to rotate the shaft lines with the unbalance modules in phase opposition;

keeping the unbalance modules of the shaft lines in phase opposition until the unbalance modules have reached a given operating speed;

after reaching the given operating speed, bringing the unbalance modules into the relative first angular position in which the unbalance modules are in phase;

prior stopping the rotary drive of the shaft lines, bringing the unbalance modules into the relative second angular position in which the unbalance modules are in phase opposition; and

stopping the rotary drive of the shaft lines after the unbalance modules have been brought into phase opposition.

9. The method according to claim 8 , wherein while the shaft lines are being driven in rotation by the drive device, said method includes the step of modifying the amplitude of vibration by modifying the angular position of the unbalance module of one shaft line relative to the angular position of the unbalance module of another shaft line.

10. The method according to claim 8 , wherein when rotation of the shaft lines is stopped, said method includes a step of bringing the unbalance modules in phase and into a low position.