Patents Assigned to STI srl
  • Publication number: 20170261111
    Abstract: Slide flow distributor (100) comprising a motor (1) moving directly a spool (2) by means of a rod (8) of the motor, a charge chamber (3) of the working fluid, in central position, in fluid communication with two discharge branches (4, 5) and two delivery branches (6, 7) and characterized in that from the portion of the spool (2) proximal to the motor (I) it is provided a pneumatic servo-actuator (9) generating a force in the same direction and development of the axial force of the motor (I), with the result that the spool (2) is accelerated in a predetermined direction, said pneumatic servo-actuator comprising a profiled body (52), a plurality of balls (50) and corresponding elastic means (5 1) which press said plurality of balls (50) on the side surface of the profiled body (52).
    Type: Application
    Filed: August 1, 2014
    Publication date: September 14, 2017
    Applicant: STI SRL
    Inventor: Flavio Tondolo
  • Publication number: 20160349768
    Abstract: Booster valve (4) for pneumatic circuits, comprising: a hollow body (5), a pilot flow inlet/outlet gap (15) communicating directly with a control volume (16), an inlet/outlet gap (45) communicating with an actuator and communicating directly with an accumulation volume (29), a supplying gap (53) communicating directly with a supplying volume (38), a discharge gap (44), an amplified discharge shutter (25) which determines the sealing towards the discharge gap (44), a central device (43) comprising an amplified charge shutter (32) which determines the sealing towards the supplying gap (53), an activation piston (22) which, subjected to the pressure acting in the accumulation volume (29) and in the control volume (16), determines the movement of the amplified discharge shutter (25) or the amplified charge shutter, and having two separated and independent charge (47) and discharge (46); gain control devices which allow an independent adjustment between the charge and the discharge step and vice versa, and the cen
    Type: Application
    Filed: November 5, 2013
    Publication date: December 1, 2016
    Applicant: STI SRL
    Inventor: Flavio TONDOLO
  • Patent number: 9250632
    Abstract: A valve positioner system with zero bleed at steady state is disclosed. The system has a pilot valve, the operation of which is controlled by an electronic circuit powered from a signaling and power connection of a positioner device. A plurality of pneumatic valves are activated and deactivated by the pilot valve to control a valve actuator. With varying configurations and arrangements of normally open or normally closed pilot valves and pneumatic valves, fail freeze and fail safe operations are contemplated. The activation and deactivation of the pilot valve is controlled by an electronic circuit that monitors a valve position signal.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: February 2, 2016
    Assignee: STI srl
    Inventors: Flavio Tondolo, Roberto Valoti
  • Patent number: 8522818
    Abstract: A booster valve comprising a housing having a signal port, an actuator port, a supply port, and an exhaust port disposed therein. Disposed within the housing are upper and lower plugs. The upper and lower plugs and the housing collectively define a signal chamber which fluidly communicates with the signal port, an actuator chamber which fluidly communicates with the actuator port, and a supply chamber which fluidly communicates with the supply port. The upper and lower plugs are selectively moveable between neutral, delivery and discharge positions. When in the neutral position, the actuator chamber is fluidly isolated from both the supply chamber and the exhaust port. When in the delivery position, the actuator chamber fluidly communicates with the supply chamber but is fluidly isolated from the exhaust port. Finally, when in the discharge position, the actuator chamber fluidly communicates with the exhaust port but is fluidly isolated from the supply chamber.
    Type: Grant
    Filed: March 30, 2009
    Date of Patent: September 3, 2013
    Assignee: STI Srl
    Inventor: Flavio Tondolo
  • Patent number: 8517335
    Abstract: A fail-freeze valve positioner system is disclosed. The system has a transducer with a first type output port connectible to a valve actuator, and a second type input port receptive to a valve position signal that is proportional to an output of the first type output port. In addition, the system has a monitoring circuit that generates a pilot activation signal while predefined conditions are met. A primary piloted valve in communication with the monitoring circuit is coupled to the first valve. The first type output port is disconnected from the valve actuator while the pilot activation signal and thus the first valve are deactivated, holding the valve actuator in place.
    Type: Grant
    Filed: May 21, 2010
    Date of Patent: August 27, 2013
    Assignee: STI Srl
    Inventors: Flavio Tondolo, Roberto Valoti
  • Publication number: 20130174915
    Abstract: A valve positioner system with zero bleed at steady state is disclosed. The system has a pilot valve, the operation of which is controlled by an electronic circuit powered from a signaling and power connection of a positioner device. A plurality of pneumatic valves are activated and deactivated by the pilot valve to control a valve actuator. With varying configurations and arrangements of normally open or normally closed pilot valves and pneumatic valves, fail freeze and fail safe operations are contemplated. The activation and deactivation of the pilot valve is controlled by an electronic circuit that monitors a valve position signal.
    Type: Application
    Filed: December 27, 2012
    Publication date: July 11, 2013
    Applicant: STI SRL
    Inventor: STI srl
  • Patent number: 8301275
    Abstract: A method and device for controlling a process variable based upon a set point is disclosed. A process variable is measured, and a proportional term is assigned to a manipulated variable that is based upon a product of a proportional gain coefficient and an error magnitude between the process variable and the set point. An integral term is added to the manipulated variable under a first set of conditions, and a derivative term is added to the manipulated variable under a second set of conditions different from the first set of conditions. The sum of the proportional term, the integral term, and the derivative term is output, resulting in the process variable being responsively adjusted thereto.
    Type: Grant
    Filed: June 4, 2010
    Date of Patent: October 30, 2012
    Assignee: STI srl
    Inventors: Flavio Tondolo, Roberto Valoti
  • Patent number: 8261625
    Abstract: A stepper actuator including a brake drum and a central gear mechanically connected thereto. The brake drum and the central gear are selectively rotatable in opposing first and second rotational directions. First and second actuation members are moveable through first and second actuation cycles to incrementally rotate the central gear. The actuation members engage and subsequently disengage the central gear as they move through their actuation cycles. The actuation members are configured to rotate the central gear during engagement therewith. A braking assembly is operatively connected to the first and second actuation members and is frictionally engaged to the brake drum to prevent rotation of the brake drum when the first and second actuation members are each in a retracted position as occurs when neither is moving through a corresponding actuation cycle.
    Type: Grant
    Filed: May 19, 2008
    Date of Patent: September 11, 2012
    Assignee: STI srl
    Inventors: Michele Picerno, Flavio Tondolo
  • Patent number: 8201580
    Abstract: A valve positioner for controlling a valve closure element is provided. The positioner includes a positioner housing with a plurality of fluid flow passageways in fluid communication with a fluid supply source and the valve closure element. The positioner housing is configured to receive a detachable spool manifold assembly. The spool manifold assembly is positioned adjacent the plurality of fluid flow passageways. The spool manifold assembly includes a reciprocally moveable spool configured to selectively port fluid flow from the plurality of fluid flow passageways. The spool manifold assembly includes a diaphragm connected to the spool via a flexible shaft. The diaphragm is in fluid communication with a transducer for receiving a fluid causing the diaphragm to expand or contract and thereby displacing the spool. The flexible shaft is radially elastic in order to minimize axial backlash between the diaphragm and the spool. The flexible shaft configuration minimizes the spool stroke.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: June 19, 2012
    Assignee: STI srl
    Inventor: Flavio Tondolo