MXPA98008341A - Actuator and articulated connection of rotate valve - Google Patents

Abstract

The present invention relates to a rotary valve actuator assembly, comprising: a tubular housing having a pair of holes on opposite sides thereof, a piston mounted on the tubular housing and movable relative to the tubular housing, as along an elongated shaft of the tubular housing, an articulated connection including a pair of arms that couple the piston through the holes in the tubular housing, the articulated connection being interconnected with a rotary arrow completely positioned to the outside of the tubular housing, wherein the movement of the piston along the axis, causes the articulated connection to rotate the arrow, and a source of fluid pressure coupled with the housing, to move the piston along the

Description

"ACTUATOR AND ARTICULATED CONNECTION OF ROTATING VALVE" FIELD OF THE INVENTION The present invention relates generally to an actuator and articulated rotary valve connection for an actuator and, more particularly, to a simplified actuator mechanism that can be produced at a lower cost and which occupies less space.

BACKGROUND OF THE INVENTION It is common in the use of rotary-operated valves, such as rotary shut-off valves and butterfly valves, to employ an actuator that resolves a transfer of the linear actuator in a rotational pulse. This rotation is used to open and close the gate or plug of the valve. One of these rotary valves is shown and described in U.S. Patent No. 5,305,987 issued to Baumann. In this reference, an articulated connection is provided at the end of the arrow. This articulated connection is interconnected with a linear drive device. These actuators often include large mechanical housings that receive air and cause the linear actuator component to be moved through interaction with a coiled diaphragm that moves in response to the applied pressure. The housing is held relative to the valve housing by a large frame that provides space for the required articulated connections to move. The approach outlined above for constructing the rotary valve unit is effective, but requires a large amount of space around the effective valve housing for the actuator mechanism. Similarly, the drive mechanism is relatively complicated and therefore proves to be costly to build and service. The service, by itself is difficult because the housing must be assembled and disassembled under the pressure of a long compression spring. The assembly and disassembly requires the respective fixing and separation of several bolts and other components. It has also been recognized that the articulated connections that resolve the linear movement in frotational movement of the arrow and frequently have a tendency to kickback and / or can be difficult to assemble into an arrow. Many rotary valve arrows define a square cross section that can create kickback if the articulated connection is not dimensioned exactly with respect to the arrow. A knurled arrow would reduce kickback but would provide a greater misalignment tendency of the articulated connection since the articulated connection can be placed in a large number of rotational orientations. However, a square cross section is more prone to allow play between the articulated connection and the arrow as the articulated connection is rotated to turn the arrow in turn. The use of fixing screws or complicated clamps to increase the resistance between the articulated connection and the arrow, have been proposed but these structures add to the complexity of the interconnection between the components and therefore increase the costs in the assembly time for a valve. U.S. Patent No. 4,345,850 issued to Baumann discloses a novel rotary valve articulated connection arrangement in which the moments and pulses are generated in each of the two opposing arms that "lock" the two arms in firm engagement with the end of the square arrow. The application of this articulated connection arrangement is limited to cases in which the two arms are in relatively close proximity to one another, since the arms must rest against each other to generate the necessary impulse for a safe engagement. It is therefore desirable to provide an articulated connection that firmly engages an arrow of square cross-section and which nevertheless allows a greater distance separation between the arm sections. Therefore, an object of this invention is to provide a rotary valve actuator assembly that is reliable, easy to maintain, which occupies less space than a more conventional actuator. This actuator must be capable of being used with a variety of rotary valve types and must allow rotation in each of the opposite directions, with relative accuracy. The actuator must generate sufficient torque to energize most small-sized or intermediate-sized valves. An articulated connection that can be used in conjunction with this actuator, would allow for firm engagement of a square configuration arrow or other configuration when two or more of the arms of the articulated connection are spaced a predetermined distance apart from each other.

COMPENDIUM OF THE INVENTION This invention overcomes the disadvantages of the prior art by providing an actuator having an elongated tubular housing with end caps that are secured free of screws or other removable fastening members. This invention also overcomes the disadvantages of the prior art by providing an articulated connection that is firmly fixed to a flat side of the arrow, using a wedge arrangement. According to one embodiment, the rotary valve actuator assembly comprises a tubular housing that can be constructed of a seamless stainless steel tube. A piston, typically constructed of a synthetic material, is mounted in the tubular housing and an elongated shaft of the tubular housing moves relative to the tubular housing. An articulated connection interengrana the piston through a hole in the tubular housing. The articulated connection can be formed with a pair of arms that engage on the opposite side of the piston. The arm may include blocks that slide along grooves that are provided in the piston. As the piston moves along the axis, the arms rotate to rotate the arrow on the rotary valve. A fluid pressure source is coupled to the tubular housing and acts on a running diaphragm which moves the piston in a predetermined direction against the force of a compression spring. An articulated connection housing is provided. The housing of the articulated connection is interconnected with a valve box and the arrow of the valve projects through the housing of the articulated connection. The housing of the articulated connection supports the tubular housing and holds the tubular housing stationary relative to the arrow. The tubular housing is dimensioned so that it can be placed in each of the opposite orientations relative to the housing of the articulated connection. At least one end cap of the tubular housing can be detachably attached to the tubular housing using a snap ring. Another end cap of the tubular housing can be permanently fixed to the tubular housing with one end of the tubular housing plastically deformed to retain the other end cap. The other end cap can be provided domed to accommodate high pressure. The articulated connection in accordance with this invention that can be used with a variety of assemblies including the actuator described herein, provides an arrow having at least one flat surface and a pair of arms with arm ends having holes defining a configuration that is approximately the same as the arrow. A center piece, which in this embodiment may include a stop member, which provides between the arms and includes a pair of wedges directed oppositely. The wedges are received by corresponding angled slots in each of the arm ends. When the ends of the arm are pressed together against the central piece, they generate force components that drive the central piece and the ends of the arm radially against the arrow. By promoting the compression force, the radial driving force is increased. This compression force is provided by an end nut in accordance with this embodiment. By way of example, round arrows with a flat surface, hexagonal arrows and square arrows may be used, together with the hinged connection of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS The aforementioned and other objects and advantages of the invention will be further elucidated with reference to the following detailed description of the preferred embodiments as illustrated by the drawings, in which: Figure 1 is a perspective view of a rotary valve assembly and actuator in accordance with this invention; Figure 2 is a detailed partial perspective view of the actuator assembly of Figure 1; Figure 3 is a detailed perspective view of the actuator assembly with the orientation of the inverted actuator; Figure 4 is a side cross section of drive assembly taken on line 4-4 of Figure 2; Figure 5 is another cross section of the actuator assembly illustrating the relative portions of the actuator piston and the hinged connection; Figure 6 is a front cross section of the actuator assembly taken on line 6-6 of Figure 5; Figure 7 is a partial cross-section of the articulated connection for use with the actuator assembly in accordance with this invention; Figures 8A, 8B and 8C are partial cross sections of the arrows of the conjointly articulated connections taken on line 8--8 of Figure 7; and Figure 9 is a somewhat schematic detailed view of an articulated connection and wedge system for use with a square cross section arrow in accordance with this invention.

DETAILED DESCRIPTION OF THE PREFERRED MODE Figure 1 illustrates, in a total view, a rotary valve and actuator assembly in accordance with this invention. The valve housing 20 can comprise any type of rotationally driven valve wherein a plug or gate member (not shown) regulates the flow between an inlet 22 and an outlet 24 based on the rotational movement of the gate. The valve 20 is connected by a flange assembly 26 to the actuator assembly 28 of this invention. The actuator assembly comprises a housing 30 having a front half 32 and a rear half 34. The rear half engages the flange assembly 26. The housing 30 can be constructed of any suitable material such as cast aluminum, iron or stainless steel. It can be formed using a die-cutting or casting process and while a relatively accurate fit of the front and back halves 32 and 34 is desirable, this portion of the housing is not typically air-tight and, therefore, a variety of processes can be used. of economic production. A counter limit / limit stop screw 36 and a rotating wheel 38 are provided. The screw 36 can be seated in each of two threaded bases 40 and 42 in the rear portion of the housing. The function of the screw 36 will be described further below. In this embodiment, the front-rear halves 32 and 34 are joined by a series of flanges 44 which receive the bolts 46. The two halves 32 and 34 are secured between the actuator element 48 in accordance with this invention. The actuator element 48 is formed as an integral unit and this mode receives fluid pressure through an accessory 50 which interconnects with a pressure line 52. The fluid pressure in the form of air, another gas or a liquid is used to control the movement of the actuator element 48 in accordance with this invention. The relative movement of the actuator is indicated in this embodiment by a scale 54 and a movable indicator 56 (Figure 1) which is fixed to one end of the actuator and articulated connection assembly which is shown in greater detail in Figure 2, below. Referring to Figures 2 to 5, the front half of the housing has been removed to reveal the internal workings of the actuator assembly. The actuator element 48 is formed of a seamless tube in this embodiment constructed of a durable material such as stainless steel. The tube material that can be easily obtained can be used in accordance with this embodiment to reduce the costs of the manufacturing time in relation to the actuator element 48. The actuator element 48 includes a pair of opposed perforated holes 60 that expose the inteira tor of the tube. The articulated connection 62 is operably connected with the actuator element 48 through the holes 60. Further refining to Figures 4 to 6, the articulated connection 62 includes a pair of arms 64 and 66 that sit firmly on an arrow 68 of square cross section. The end 70 of the arrow 68 can be threaded (see Figure 3) to receive a retaining tine 72 as shown in Figure 1. The mechanism for securing the arms 64 and 66 on the arrow 68 will be described further below. Each arm 64, 66 includes a block 74 and 76 of associated guidance, respectively. The guide blocks are received by the forming grooves 80 formed in the side walls of the actuator piston 82 of this invention. As shown in detail in Figure 5, the forward and backward movement (double arrow 84) of the piston 82 within the actuator tube causes the corresponding rotation movement (curved arrows 86) of the articulated connection 62. The blocks 74 and 76 move along the respective slots 80 as the hinged connection 62 rotates (see double arrows 88 in Figure 5). Therefore, the slots accommodate the change in arm position in a direction transverse to the central axis of the cylindrical tube. The blocks 74 and 76 are pivoted relative to their respective arms 64 and 66 to facilitate movement along the slots 80. The pivotal movement is achieved using the screws 88 that pivot freely relative to the ends 90 and 92 of the arm (Figure 6). The piston in this mode is constructed of a durable plastic such as nylon or Delrin®. These materials are self-lubricating and, therefore, a minimum lubrication of the piston in relation to the tube is required. The piston 82 includes a hollow center which is open in the front part 96 to receive a spring 98. The springs rest on the rear wall 100 of the piston 82 and on a front wall 102 of the tube. The force of the spring constant and applied relative to the piston is selected so that the force of the spring is exceeded and the piston moves to a fully forward position (103 in Figure 5) when maximum pressure is applied to the actuator. In this mode, a maximum pressure of approximately 7.03 kilograms per square centimeter is proposed, generating a maximum force of approximately 227 kilograms inside the piston and a torque of approximately 5,175 kilograms. These values can be changed depending on the size and function of the actuator assembly, in accordance with this invention. The piston 82 of this embodiment includes a main wall section 106 that is separated from the inner wall of the tube. Two sets of guide rings 108 and 110 mesh the inner wall of the tube. By minimizing the surface contact between the piston 82 and the inner wall of the tube, the friction is reduced and the risk of interlocking between the components is minimized. The rear ring 108 has a diameter that is approximately 1.59 millimeters smaller than the inner diameter of the tube. The outer ring 110 is formed more closely with the diameter of the inner diameter of the tube. The hole 60 makes the deformation of the tube more similar and, therefore, the more similar conformation of the front ring assembly 110 provides additional support to the tube, at its weakest point. As mentioned above, the tube of the actuator element 48 is constructed of a seamless stainless steel tube. For the illustrated valve, the diameter of the tube is approximately 10.16 centimeters. The thickness of the wall is approximately 1.59 millimeters. The end cap 102 is removable to serve the interior of the member 48. A pressure ring 120 sits within a recess 122 formed within the tube. The recess has sufficient depth to prevent the pressure ring from moving axially out of the opening of the tube. The end cap 102 that is constructed of stainless steel or a similar durable material includes a shoulder 124 that abuts against the snap ring. As detailed in Figures 2 and 3, a plastic cap 126 can be installed in a hole in the end cap. This hole and cover 126 can be omitted, however. The end cap 102 is installed and removed by pushing the cap inward against the spring 98 until it clears the pressure ring 120. Once the end cap 102 of the pressure ring 120 is cleared, it can be removed or installed relative to the recess 124. The pressure rings having large diameters as shown can be obtained from a variety of commercial sources in Germany and in Germany. any other site. When it is under the load of the spring, it is impossible to dislodge the pressure ring 120 since the peripheral shoulder 125 of the cover 102 hermetically meshes the internal diameter of the pressure ring, thus preventing the pressure ring from moving radially inwardly. outside the slot 122. The actuator element 48 also includes a cover 130 of opposite base that is molded or formed in a domed configuration. This vaulted configuration helps maintain high pressure. An orifice 132 places the fluid line 52 in communication with the interior of the actuator element in the vicinity of the end cap 130. The end cap 130 is permanently secured in the tube by plastically deforming the end wall 134 formed at the rear end of the tube. The deformed end wall prevents the end cap 130 from moving axially outward away from the tube. Appropriate solders or solder joints can also be applied between the tube and the end cap. It is generally proposed that the end caps 130 be pressed inwardly. The end cap 130 includes an approximately cylindrical inner wall section 136 that extends into the inner wall of the tube. The inner wall section 136 includes a recess 138 for receiving the base 140 by doubling as a radial stationary seal on a running diaphragm 142. The rolling diaphragm can be obtained from a variety of commercial sources. In this embodiment, it is a fabric reinforced with rubber-nitrile that has a thickness of approximately 1.016 millimeters. The running diaphragm occupies the space between the main wall 106 of the piston 82 and the inner wall of the tube at the rear of the ring 108. As shown in Figure 5, the pressure causes the diaphragm to rest on the rear wall 100 of the piston 82, thus moving the piston forward to the front end cover 102. The diaphragm forms a positive fluid seal within the back of the actuator element 48. In this manner, the actuator and piston assembly are open and not sealed forward of the diaphragm 142. It should be apparent from this disclosure that the actuator element 48 shown and described is relatively easy to construct and maintain and requires less space than the actuators. conventional It is constructed essentially free of screws or other fasteners and can be considered disposable when it has been damaged. However, the service provided to the actuator is possible through the removable front cover 102, as mentioned above. In addition to the disadvantages described above, FIG. 2 and FIG. 3 show the additional versatility of the actuator assembly in accordance with this invention. The recess 122 adjacent the front cover 102. serves as a positioning ring that sits within the corresponding recesses 148 within the half 34 of the rear housing (Figure 2). The actuator element 48 is symmetrically dimensioned so that it can be rotated 180 ° and set in an opposite set of recess 150 within the rear half 34 of the housing (Figure 3). Therefore, the actuator element 48 can be positioned to operate in each of the opposite directions relative to the valve, by a simple repositioning process. In this modality, the unused set of recesses (eg the recess that is not engaged in the front cover assembly can be filled with an O-ring of appropriate size and thickness to settle more securely in the middle section of the actuator element 48.) The upper part of the articulated connection 62 includes a stop structure 150 that rotates together with the arms 64 and 66. The stop structure includes a roller 152 that reduces friction when engaging the threaded stops placed within the bases 40 and 42. As described above, the screw 36 and an opposite screw (156 in Figure 5) can be moved if desired relative to their respective bases 40 and 42, to define the limit stop positions of the hinged connection 62. On the other hand, the limit stop positions are defined by a minimum and maximum travel of the piston 82 within the tube of the actuator element 48. The screw 36 can also be used as a mechanism to counteract manual in case of pressure failure. As the screw is rotated inward it causes the stop structure 150 to rotate the arrow 68 thereby moving the valve gate (not shown). 11 movement of the stop structure 150 exceeds the force imparted by the spring 98. With further reference to Figures 7 to 9, the clamping mechanism for an articulated connection 62 in accordance with this invention is shown and described. Figure 7 illustrates with particularity the assembly of the articulated connection 62 on the arrow 68 of square cross-section that is interconnected with the gate of a rotary valve (not shown). In this embodiment, the square cross section portion of the arrow 68 is formed of a larger diameter round arrow wherein the round portion 160 of the arrow defines a shoulder 162, against which an inner end of the arm 64 abuts. free end of the arrow 68 in this embodiment is rounded and is provided with an end section 70 having threads for receiving a nut 72. The length of the square cross section portion of the arrow is selected so that the nut 72 can Fully tighten to apply force (arrow 164) to the articulated connection assembly 62. In this embodiment, the stop portion 150 defines a center piece of the hinged connection 62. It includes a square cross-section hole that is shaped relatively closely to the size and configuration of the arrow 68 of square cross-section. In this embodiment, the opposite upper legs of the stop structure 150 define the wedges 166 that extend in opposite directions away from the stop structure. In particular, the wedges 166 define extensions that extend beyond the end walls 168 of the lower portion 170 of the stop structure 150. Also referring to Figures 8A and 9, each arm 64 and 66 includes a mounting arm or end of the respective arm 174 and 176 that also has a square cross-sectional hole formed therein. These holes conform to the size and configuration of the arrow 68. Each end of the arm 174 and 176 also includes an internal facing triangular recess 180 that is dimensioned and positioned to receive a respective wedge 166. The angle of the wedge can be about 15 ° more or less. This angle can be varied depending on the application. Referring again to Figure 7, exerting a force (arrow 164) on the articulated connection 62, the opposing arm ends 174 and 176 are forced towards compression (arrow 184 and 186, respectively) against the wedges 166 of the structure 150. of stop. Since the wedges and the shaping grooves on the arm ends 174 and 176 are at an angle, they resolve the compression force (arrow 184 and 186) into perpendicular force components) arrow 194, 196 and 198 that drive the ends of the arm 174 and 176 and the stop structure 150 in firm engagement with the flat pieces of the arrow 68. The tighter the nut 72 at the end 70 of the arrow is twisted, the greater the engagement of the components of the articulated connection with the parts plane of the arrow 68. Provided that the end walls 174 and 176 of the arrows are made sufficiently strong, considerable clamping force can be imparted to the components of the articulated connection. This clamping force considerably reduces the possibility of kickback when the arms 64 and 66 are actuated to rotate the arrow 68. Note that, as illustrated in Figure 7, a space 200 must be provided between the end walls 168 of the stop structure, and the corresponding end walls 202 of each end 174 and 176 of the arm. Without this space, the components do not have sufficient space to move perpendicularly to a fully engaged position in the flat pieces of arrow 68. It should be evident that the basic principle described herein is applicable to a variety of arrow configurations. It is generally desirable that the arrow has at least one flat piece. For example, Figures 8B and 8C show the arrows 268 and 368 which are respectively round and hexagonal. Each arrow 268 and 368 includes at least one flat piece 290 and 390 on which a wedge 266 and 366 may be seated. The respective arm end 274 and 374 includes a hole conforming to the configuration of the arrow with a recess 280 and 380 at an appropriate angle, respectively. In order to receive the wedge 266 and 366. Also, the central wedge carrier portion need not include a surrounding housing with a hole to receive the arrow. Instead, as shown in Figure 9, the center piece may comprise a single wedge plate 208 with wedge 166 that is defined at either end. The length of plate 208 or other wedge carrier structure is infinitely variable and therefore the arms can be placed at considerable distance from one another according to this invention. Further, even when the arrow includes a stop wall 162, nuts or other clamping structures may be provided at both ends and adjusted to change the compression force and location of the articulated connection as appropriate. It should be apparent that the arm fixing mechanism, which is described herein, allows the arms and arrows to be produced at a slightly lower tolerance while still allowing a relatively relatively kick-free fit. The arms can be produced using casting processes or other forming processes, in accordance with this modality. The aforementioned has been a detailed description of a preferred embodiment. Various modifications and equivalents may be made without departing from the spirit and scope of this invention. For example, even when a rolling diaphragm is used in accordance with this embodiment, a sealed piston may be substituted where desirable. The size and configuration of the components may be varied for use with different types of rotary valves and the actuator assembly described herein may be used with or without the singular articulated connection fixing mechanism as shown and described. Similarly, the articulated connection fixing mechanism can be applied to other structures, in which it is desirable to secure the arms on the arrows, using a quick and inexpensive technique. Accordingly, this description is intended to be taken only by way of example and not otherwise to limit the scope of the invention.

Claims (29)

CLAIMS:

1. A rotary valve actuator assembly comprising: a tubular housing; a piston mounted in the tubular housing and moving relative to the tubular housing along an elongated shaft of the tubular housing; an articulated connection which interengages the piston through a hole in the tubular housing and which is interconnected with a rotary arrow wherein the movement of the piston along the axis causes the articulated connection to rotate the arrow; and a fluid pressure source coupled with the housing to move the piston along the axis.

2. The rotary valve actuator assembly according to claim 1, further comprising a housing of the articulated connection that receives the tubular housing that holds the tubular housing stationary relative to the arrow.

The rotary valve actuator assembly according to claim 2, wherein the tubular housing includes a rolling diaphragm positioned between a closed end of the tubular housing and the piston.

4. The rotary valve actuator assembly according to claim 3, further comprising a compression spring positioned between one end of the tubular housing and a portion of the piston remote from the running diaphragm for pushing the piston in a predetermined direction which is overcome by the application of fluid pressure.

The rotary valve actuator assembly according to claim 4, wherein the tubular housing includes a pair of elongated holes on each of the opposite sides thereof and wherein the articulated connection includes arms that engage a portion of the piston to through the holes.

The rotary valve actuator assembly according to claim 5, wherein the arms include pivot blocks that slide along the slots formed in the piston.

The rotary valve actuator assembly according to claim 6, wherein the arrow includes at least one flat surface therein and wherein the arms include arm ends each having flat surfaces that engage the flat surface in the arrow.

The rotary valve actuator assembly according to claim 7, wherein the arrow comprises an arrow of square cross section having four planar surfaces.

The rotary valve actuator assembly according to claim 8, further comprising a stop structure positioned between each of the arms and extending in a direction opposite to an extension direction of the arms, and further comprising at least one adjustable stop constructed and positioned to engage the stop structure at predetermined variable locations to limit the rotation of the arrow.

The rotary valve actuator assembly according to claim 9, wherein the stop structure includes a roller engaging the adjustable stop.

The rotary valve actuator assembly according to claim 10, wherein the adjustable stop comprises a screw and wherein the housing of the articulated connection includes a threaded base for receiving the screw.

The rotary valve actuator assembly according to claim 11, wherein each of the ends of the arm includes an angled slot and wherein the stop structure includes a pair of opposite wedges and wherein the slot and wedges they are constructed and positioned to be interlocked so that each end of the arm and the abutment structure abuts against the arrow under axial pressure.

The rotary valve actuator assembly according to claim 1, wherein the piston comprises a synthetic material.

14. The rotary valve actuator assembly according to claim 13, wherein the piston includes guide rings having diameters that are approximately equal to the diameter of an inner wall of the tubular housing, and wherein the piston includes a main wall that is distant from the inner wall of the tubular housing.

The rotary valve actuator assembly according to claim 1, wherein the tubular housing comprises a seamless stainless steel tube.

The rotary valve actuator assembly according to claim 15, wherein the tubular housing includes a removable end cap retained in the tubular housing by a pressure ring.

The rotary valve actuator assembly according to claim 16 further comprising a recess for receiving the pressure ring formed in the inner wall of the tubular housing.

18. The rotary valve actuator assembly according to claim 17, further comprising an articulated connection housing for retaining the tubular housing, the housing of the articulated connection includes a recess for receiving a projection formed on an external wall adjacent to the recess to receive the pressure ring.

The rotary valve actuator assembly according to claim 18, wherein the articulated connection housing includes two pairs of recesses each to receive the projection of the tubular housing in each of the opposite orientations of the tubular housing relative to the articulated connection housing.

20. An articulated connection for a rotary arrow comprising: an arrow mounted so as to be able to rotate, the arrow including at least one flat surface extending therethrough through a portion thereof and the arrow having an elongated axis; a stop placed along the arrow; a pair of arms having arm ends, as the arm ends have holes dimensioned and positioned to pass through the portion of the arrow having the flat surface, each of the holes includes an angled recess; a wedge structure having a predetermined length and a pair of wedge surfaces dimensioned and positioned to inter-engage with the recess at an angle at each of the arm ends; and an adjustable end stop which applies a force to each of the arm ends and the wedge structure in the direction of the axis, wherein at least one of the ends of the arm rests against the stop so that each one end of the arm is forced into engagement with the arrow and the wedge structure is forced into engagement with the flat surface.

The articulated connection according to claim 20, wherein the wedge structure includes a body having a hole dimensioned and positioned to pass over the portion of the arrow having a flat surface and wherein the body has edges on top of at least a portion thereof.

22. The articulated connection according to claim 21, wherein the wedge surfaces extend outwardly at the end edges.

The articulated connection according to claim 22, wherein the wedge surfaces are dimensioned and positioned to extend lengthwise and to mesh with the flat surface.

24. The articulated connection according to claim 20, wherein the arrow comprises an arrow having a square cross section.

The articulated connection according to claim 20, wherein the arrow comprises an arrow having a round cross section in a portion thereof.

26. The articulated connection according to claim 20, wherein the arrow comprises an arrow having a hexagonal cross-section.

27. The articulated connection according to claim 20, wherein the wedge structure includes a stop structure extending therefrom dimensioned and positioned to engage at least one stop when the arrow rotates toward a predetermined angular location.

28. A rotary valve actuator assembly comprising: a housing of the articulated connection interconnected with a valve housing having a valve arrow extending therethrough; a tubular housing supported by the housing of the articulated connection and having a piston therein that moves along an elongated shaft of the tubular housing in response to the applied fluid pressure; an interconnected articulated connection between the piston and the arrow to translate the linear movement of the piston in rotation movement of the arrow; a compression spring that pushes the piston in a predetermined direction with a pushing force, the pushing force being overcome by fluid pressure; and the end layers are positioned at opposite ends of the tubular housing, the end caps being attached to the tubular housing free of threaded fasteners.

29. A rotary valve actuator assembly according to claim 28, further comprising a pressure ring positioned at one end of the tubular housing constructed and positioned to removably retain one of the end caps.