Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
  • F16K31/00—Actuating devices; Operating means; Releasing devices
  • F16K31/12—Actuating devices; Operating means; Releasing devices actuated by fluid
  • F16K31/16—Actuating devices; Operating means; Releasing devices actuated by fluid with a mechanism, other than pulling-or pushing-rod, between fluid motor and closure member
  • F16K31/165—Actuating devices; Operating means; Releasing devices actuated by fluid with a mechanism, other than pulling-or pushing-rod, between fluid motor and closure member the fluid acting on a diaphragm
  • F16K31/1655—Actuating devices; Operating means; Releasing devices actuated by fluid with a mechanism, other than pulling-or pushing-rod, between fluid motor and closure member the fluid acting on a diaphragm for rotating valves

Definitions

• This disclosure relates generally to a method and rotary valve actuator to apply increased torque proximate the open or closed position of a valve and, more particularly, to a method and rotary valve actuator having a lever disposed at a rotational position to apply maximum torque proximate the fully open or the fully closed position of the valve.
• rotary valves such as ball valves, butterfly valves, eccentric-disk valves,-eccentric-plug valves, etc.
• rotary valves typically include a fluid flow valve member disposed in the fluid path and coupled rotatably to the body of the rotary valve via a shaft.
• a portion of the shaft extending from the rotary valve functions as a valve-stem, and an end of the shaft or valve stem may be coupled operatively to an actuator (e.g., a pneumatic actuator, an electric actuator, a hydraulic actuator, etc.) Df the rotary valve.
• an actuator e.g., a pneumatic actuator, an electric actuator, a hydraulic actuator, etc.
• the actuator may include a lever coupled to the shaft and the lever may be displaceable by an actuator member such as, for example, an actuator rod, whereby a linear displacement of the actuator rod is converted into a rotational displacement of Hie lever, the shaft and the valve member.
• a controller may cause the actuator to ⁇ otate the lever and shaft and, thus, the valve member to a desired angular -position to vary an amount of fluid flowing through the rotary valve.
• the valve member is typically configured to -engage an annular or circumferential seal that encircles the flow path through the rotary valve to prevent the flow of fluid (e.g., in one or both directions).
• rotary valve actuators and in particular quarter-turn rotary valve actuators, which have a rotational displacement of approximately ninety degrees, apply the maximum amount of torque to the valve member at approximately the midpoint of the rotation of the valve member Xi.e., at about forty-five degrees from the fully open or the fully -closed positions).
• the highest torque requirements for rotary valves usually occur when the valve member is proximate either the fully closed or the fully open position of the valve member.
• the maximum amount of torque is not applied to the valve member.
• a rotary valve actuator comprises an elongated actuator member configured to move in response to a control signal and a lever configured to receive a shaft associated with a valve.
• the rotary valve actuator may also include a lever arm coupled rotatably to an end of the actuator member so that when the lever is coupled to the shaft of the valve, the elongated actuator member applies a maximum torque to the shaft when the valve is proximate a fully closed or a fully open position.
• a method to apply maximum torque proximate a fully-open or a fully closed position of avalve of a rotary valve actuator comprises positioning the lever so that the valve is in a fully open position or a fully closed position when a longitudinal axis of the lever is at a first rotational position that is substantially less than or substantially greater than forty five degrees from a second rotational position at which the actuator member is substantially perpendicular to the longitudinal axis of the lever, and displacing the actuator member so that when the lever rotates to the rotational position at which the actuator member is substantially perpendicular to the longitudinal axis of the lever, the maximum torque is applied to the valve proximate the fully open or the fully closed position of the valve.
• FIG. 1 is a cross-sectional view of an example rotary valve actuator. .
• FIG.2 is a cross-sectional view of the-example rotary valve actuator in FIG. 1 illustrating the rotary valve and valve member.
• FIG.3 is an enlarged cross-sectional view of a portion the example rotary valve actuator of FIG. 1. .
• FIG. 3A is a depiction of alternative couplings of the actuator member with the lever and the lever with the actuator shaft of the rotary valve actuator. .
• FIG. 4 is a flow chart of an example process to apply maximum torque proximate the fully open of the fully closed of a valve of a rotary valve actuator. . '
• the example method and rotary valve actuator disclosed herein applies increased torque proximate the open or the closed positions of a valve.
• typical rotary valve actuators which apply the maximum amount of torque proximate the midpoint of the range of rotation of the valve member (i.e., about halfway between the fully open position and the fully closed position)
• the example method and rotary valve actuator applies the maximum amount of torque proximate the fully open or the fully closed position of the valve member. .
• FIG. 1 is a cross-sectional view of an example rotary valve actuator 100.
• the rotary valve actuator 100 includes an actuator body 101 having a diaphragm casing 102 containing an inlet 103, and a diaphragm 104 located adjacent a diaphragm plate 106 coupled to a diaphragm stem 108.
• the diaphragm plate 106 engages three actuator springs 110, 112 and 114 disposed between the diaphragm plate 106 and body shoulders 116, 118 and 120, respectively.
• the diaphragm stem 108 is coupled to an actuator rod or elongated actuator member 122 coupled -(e.g., via threads) to a rod end 123 having a rod end bearing 126.
• the rod end bearing 126 is coupled *o an actuator lever 130 at a lever arm 13I 3 and the lever 130 is rotatab ⁇ e about an axis 137.
• the actuator lever 130 is coupled to an actuator shaft 136 that is coupled to a valve member 138 of the rotary valve 139 ⁇ see FIG.2).
• the TOtary valve actuator 100 is illustrated in FIG. 1 as a pneumatic rotary . valve actuator, the rotary valve actuator WO may, alternatively, 'be any of ' several types of actuators such as, for example, an -electric actuator.or a . hydraulic actuator.
• the valve member 138 can be any valve such as, for example, a butterfly valve, an eccentric-disk valve, or an eccentric-plug valve that may be rotated by a rotary valve actuator, such as, for example* the rotary valve actuator 100.
• the rotary valve actuator 100 receives a cdntrol signal such as, for example, compressed air, at the inlet 103 to displace the diaphragm 104 and the diaphragm plate 106 against the springs 110, 112 and 114.
• a cdntrol signal such as, for example, compressed air
• displacement of the diaphragm plate 1O6 in the direction of • arrow 200 results in a corresponding displacement of the actuator member 1-22 to rotate the actuator lever 130 and the actuator shaft I36 about the axis 137 and rotate the valve member 138 to vary or control the flow of fluid through the rotary valve 139.
• FIGS 1 and 2 an enlarged portion of the example notary valve actuator 100 shown in FIGS 1 and 2 is illustrated.
• the actuator -member 122 is displaced in the direction of arrow 300 to rotate the actuator-lever 130.
• the force exerted by. the actuator member 122 is depicted in BIG.3 as a vector or force A.
• the moment of a force such as, for example, force A in FJG. 3,
• -S - may be defined as a turning effect produced by a force at some distance from an axis of rotation.
• the moment of a force may be defined as a measure of the tendency of the force t ⁇ ause a body to rotate about a specific point or axis (i.e., the center of moments).
• the moment of the force A applied by the actuator member 122 to the actuator lever 130 is the product of the force A times the length d of the moment arm B from the axis 137 (i.e., the center of moments) to the point C on the lever 130 when the force A is perpendicular to the moment arm B.
• a similar measure of the operation of the rotary valve actuator 100 is the torque applied by the lever 130 to the rotary shaft 136 and the valve member 138.
• ⁇ is the angle of F relative to r
• the actuator lever 130 is displaced or rotated by the actuator member 122 through an arc of approximately ninety degrees, as illustrated by arc D.
• the lever 130 would be positioned initially so that its longitudinal axis or centerline position E is forty-five degrees from a position at a longitudinal axis or centerline position F where the actuator member 122 is disposed perpendicular to the lever 130.
• the ⁇ enterline position F may be referred to as the moment arm position F of the lever 130.
• the operatively coupled valve member 138 would be in either a fully closed or a fully open position when the lever 130 is positioned along the centerline position E, whereby the rotation of the lever 130 through approximately ninety degrees to a longitudinal axis or centerline position E' would apply the maximum amount of torque to -the valve member 138 at approximately the midpoint of the rotation"(i.e.. at forty- five degrees of rotation when the actuator member 122 is perpendicular to the lever 130 at centerline position F).
• the largest torque requirements for a rotary valve actuator such as, for example, the example rotary valve actuator 100, are at the fully open or the fully -closed positions of the associated valve member 138.
• a known rotary valve actuator which attains the moment arm position F at approximately the midpoint between the fully open or the fully closed position of the valve member, is not able to apply the maximum amount of torque to the valve member proximate the fully open or the fully closed positions of the valve member.
• the example method and rotary valve actuator 100 disclosed herein apply maximum torque to the valve member 138 proximate the-fully open or the fully closed positions of the valve member 138.
• the example rotary valve actuator 100 may include the actuator lever 130 positioned at an initial angular or rotational position to apply the maximum torque closer to or proximate either the fully open or the fully closed positions of the valve member 138.
• FIO. 3 illustrates the lever 130 at an initial rotational position along a centerline position H whereby the lever 130 is disposed less than forty-five degrees from the moment arm position F of the lever 130.
• the valve member 138 is in a closed positioning., fully closed position) when the lever 130 is disposed at the -centerline, position H.
• the lever 130 When the actuator member 122 is displaced in the direction of arrow 300 in FIG. 3, the lever 130 is rotated through approximately ninety degrees to a-centerline position H'.
• the initial rotational position of the lever 130 at the -centerline position H is offset angularly a predetermined amount of «degrees'from the centerline position E, as represented by an arc 'G 5 and the angular offset is
• - S - preferably, but not necessarily, within the range often to twenty degrees.
• a corresponding amount of angular offset at the end of the rotation of the lever 130 is illustrated by an arc G' having a 'corresponding range often to twenty degrees.
• the lever 130 may be disposed at an initial rotational position along its longitudinal axis or centerline position J, whereby the lever 130 is disposed greater than forty-five -degrees from the moment arm position F of the lever 130.
• the valve member 138 may be at a fully closed position when the lever 130 is disposed at ⁇ enterline position J.
• the actuator member 122 is displaced in the direction of arrow 300 in FIG. 3
• the lever 130 is rotated through approximately ninety degrees to longitudinal axis or centerline position J'.
• the initial rotational position of the lever 130 at the centerline position J is offset angularly a predetermined amount of degrees from the centerline position E, as represented by an arc I, and the angular offset is preferably, but not necessarily, within the range often to twenty degrees.
• a corresponding amount of angular offset at the-end of the rotation of the lever 130 is illustrated by an arc I' having a-iange of ten to twenty degrees.
• the actuator lever 130 may be disposed at the initial rotational positions of the centerlines H or J or, for example, at other initial rotational positions within the preferred angular offset range often to twenty degrees, by utilizing different couplings of the actuator member 122 to the lever 130 or the lever 130 to the actuator shaft 136.
• FIG. 3A alternative couplings of the actuator member 122-tshown in phantom) with the lever 130 and the lever 130 with the actuator shaft 136 of the rotary actuator 100, are illustrated.
• the actuator lever 130 may include a plurality of openings 132, 133 and 134 for coupling the actuator member 122 to the lever 130 by a fastener (not shown).
• the openings 132, 133 and 134 are angularly spaced-apart relative to one another and the axis 137.
• the openings 132, 133 and 134 are located such that when the actuator member 122 is coupled with the lever 130 by the fastener, the lever 130 may be positioned at different initial rotational positions less than or greater than a position forty- five degrees (e.g., the centerline E) from the moment arm position "F, and within the range often to twenty degrees from the position at forty-five degrees.
• the rod end 123 (shown in phantom) is threadedly coupled to the actuator member 122 and includes the rod end bearing 126 coupled to the lever 130.
• the rotary valve actuator 100 will maintain the actuator member 122 in an initial or at-rest position of the actuator member 122 as illustrated in FIG; 1.
• the lever 13G may be disposed at different initial rotational positions less than or -greater than the -centerline E position forty-five degrees from the moment arm F.
• FIG.3A also illustrates another alternative coupling assembly to position the lever 130 at different initial rotational positions.
• the actuator shaft 136 may include therein openings 140, 141 and 142 -(shown in phantom) to enable the lever 130 to be coupled by a fastening member 143 at different angular positions relative to the actuator shaft 136.
• the fastening, member 143 e.g., a pin
• the opening 141 is illustrated as being located at the opening 141.
• FIG. 4 is a representative flow-chart of an example process or method 400 to apply maximum torque proximate the fully open or the fully closed positions of a valve operated by a rotary valve actuator.
• the example method 400 includes providing a rotary valve actuator (e.g., the rotary valve actuator 100 in FIGS. 1-3A) having an actuator member (e.g., the actuator member 122) that rotates a lever (e.g., the actuator lever 130) at least about ninety degrees and the lever coupled operativelyto a valve (e.g., the valve 138 in FIG. 2).
• the lever is positioned -so the valve is disposed at a fully open or a fully closed position (e.g., see the fully closed valve 138 in FIG.2) and the lever at an initial rotational position (e.g., the lever 130 positioned at an initial rotational position such as, for example, the centerline H in FIG.
• the lever is positioned so the initial rotational position (e.g., the lever 130 positioned at either the centerline H or the centerline J in FIG. 3) is ten to twenty degrees less than or -greater than the position at forty-five degrees (e.g., the centerline E), block 406.
• the actuator member e.g., the actuator member 122 in FKJ.3 is displaced to rotate the lever (e.g., the actuator lever 130) to the position of the actuator member perpendicular to the lever-(e.g., the centerline or moment arm position F in FIG. 3) to apply maximum torque proximate fee folly open or the fully closed position of the valve (e.g., the fully closed position of the valve member 138 in FIG. 2).
• the positioning of the lever at the initial rotational position angularly offset from the typical initial rotational position of the lever in a known rotary valve actuator enables the rotary valve actuator to apply the maximum amount of torque to the valve proximate -either the-fully open or the fully closed position of the valve.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Mechanically-Actuated Valves (AREA)
• Lift Valve (AREA)
• Fluid-Driven Valves (AREA)
• Actuator (AREA)

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• 2006
  • 2006-05-18 US US11/436,451 patent/US20070267587A1/en not_active Abandoned
• 2007
  • 2007-04-17 BR BRPI0712906A patent/BRPI0712906B8/pt not_active IP Right Cessation
  • 2007-04-17 WO PCT/US2007/009309 patent/WO2007136481A1/en not_active Ceased
  • 2007-04-17 MX MX2008014675A patent/MX2008014675A/es active IP Right Grant
  • 2007-04-17 CN CN2007800180356A patent/CN101449092B/zh active Active
  • 2007-04-17 DE DE602007008245T patent/DE602007008245D1/de active Active
  • 2007-04-17 EP EP07755541A patent/EP2035733B1/en active Active
  • 2007-04-17 CA CA2652378A patent/CA2652378C/en active Active
  • 2007-04-17 JP JP2009510946A patent/JP5393448B2/ja not_active Expired - Fee Related

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