Patents Assigned to STI srl
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Publication number: 20170261111Abstract: 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: ApplicationFiled: August 1, 2014Publication date: September 14, 2017Applicant: STI SRLInventor: Flavio Tondolo
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Publication number: 20160349768Abstract: 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 cenType: ApplicationFiled: November 5, 2013Publication date: December 1, 2016Applicant: STI SRLInventor: Flavio TONDOLO
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Patent number: 9250632Abstract: 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: GrantFiled: December 27, 2012Date of Patent: February 2, 2016Assignee: STI srlInventors: Flavio Tondolo, Roberto Valoti
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Patent number: 8522818Abstract: 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: GrantFiled: March 30, 2009Date of Patent: September 3, 2013Assignee: STI SrlInventor: Flavio Tondolo
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Patent number: 8517335Abstract: 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: GrantFiled: May 21, 2010Date of Patent: August 27, 2013Assignee: STI SrlInventors: Flavio Tondolo, Roberto Valoti
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Publication number: 20130174915Abstract: 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: ApplicationFiled: December 27, 2012Publication date: July 11, 2013Applicant: STI SRLInventor: STI srl
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Patent number: 8301275Abstract: 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: GrantFiled: June 4, 2010Date of Patent: October 30, 2012Assignee: STI srlInventors: Flavio Tondolo, Roberto Valoti
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Patent number: 8261625Abstract: 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: GrantFiled: May 19, 2008Date of Patent: September 11, 2012Assignee: STI srlInventors: Michele Picerno, Flavio Tondolo
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Patent number: 8201580Abstract: 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: GrantFiled: August 28, 2008Date of Patent: June 19, 2012Assignee: STI srlInventor: Flavio Tondolo