GB2518599A

GB2518599A - Valve actuator

Info

Publication number: GB2518599A
Application number: GB1315999.1A
Authority: GB
Inventors: Paul Wilkinson; Edward Haigh; Martin Parsons
Original assignee: Perkins Engines Co Ltd
Current assignee: Perkins Engines Co Ltd
Priority date: 2013-09-09
Filing date: 2013-09-09
Publication date: 2015-04-01
Anticipated expiration: 2033-09-09
Also published as: GB2518599B; CN204042153U; GB201315999D0

Abstract

An actuator 122 for a bypass valve 120 includes a housing 202 defining a chamber provided with an air feed 214 and a diaphragm 222 provided with a linkage coupled to the bypass valve 120. The chamber is subject to varying positive pressures which cause the diaphragm 222 to move outwardly relative to a neutral position. Under some conditions, negative pressure is created which urges the diaphragm 222 inwardly, which is undesirable. The invention provides an abutment 216 within the chamber to restrict the inward movement of the diaphragm 222.

Description

VALVE ACTUATOR

Tcchnical Field

100011 The present disclosure relates to an actuator and more specifically to the actuator for a valve asscmbly.

BackQround 10002] Usually, a diaphragm type valve actuator used for actuation of a valve assembly is designed for operation in one direction only, meaning that the diaphragm is intended to moye forward or outward of a neutral position, but not rearward or inward of the neutral position. In particular, the diaphragm type valve actuator includcs an actuation chamber in communication with a diaphragm. A positive fluid (typically air) pressure in the actuation chamber causes the diaphragm to move outwardly relative to the actuation chamber.

Under some operating conditions thc fluid in the actuation chamber may see a ncgativc prcssurc. Thc ncgativc prcssurc may urge thc diaphragm inwardily with respect to the actuation chamber. Such an inward movement of the diaphragm may be undesirab'e and detrimental. This undesirable movement of the diaphragm may cause damage to the diaphragm or in some instances may cause a permanent change in a profile of the diaphragm.

100031 Hence, there is a need for an improved system to preveilt the undesirable movement of the diaphragm.

Summary of the Disclosure

100041 In one aspect of the present disclosure, an actuator having a housing defining an interior space is provided. The housing includes a diaphragm configured to enclose the interior space and being moveable between a neutral position whereat the interior space has a lower volume and an extended position whereat the interior space has a higher volume. The housing includes an air inlet provided on the housing and configured to provide an airflow into thc intcrior space. The housing further includes an abutment provided in the interior space and configured to restrict inward movement of the diaphragm beyond its neutral position.

100051 Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Brief Description of the Drawings

100061 Figure 1 is a schematic illustration of an cxcmpaiy enginc system; 10007] Figure 2 is an exploded cross sectional view of an actuator according to

the present disclosure;

100081 Figure 3 is a perspective view of a first configuration of an abutment of the actuator of Figure 2; 10009] Figure 4 is a perspective view of a sccond configuration of the abutment of the actuator of Figure 2; 100101 Figure 5 is a perspective view of a third configuration of the abutment of the actuator of Figure 2; and 100111 Figurc 6 is a pcrspective view of a fourth configuration of the abutment of the actuator of Figure 2.

Detailed Description

100121 Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or the like parts. Referring to Figure 1, an exemplary engine system 100 is illustrated. The engine system 100 includes an cngine 102. The cnginc 102 may bc any intcrnal combustion enginc known in the art. The engine 102 may be powered by any fuel including, but not limited to, petrol, diesel, natural gas or a combination thereof.

100131 The engine 102 may include an engine block (not shown). The engine 102 may also include a cylinder head (not shown) coupled to the engine block.

The engine 102 includes an intake manifold 104 provided in fluid communication with the engine block and/or the cylinder head. The intake manifold 104 is configured to provide an airflow to the engine 102 for combustion process.

10014] The engine 102 includcs an exhaust manifold 106 provided in fluid communication with the engine block and/or the cylinder head. The exhaust manifold 106 is configured to receive an exhaust gas feed from the engine 102 after the combustion process. The exhaust manifold 106 is fluidly connected to a turbocharger 108 via a turbocharger inlet line 110. The turbocharger inlet line is configured to provide the exhaust gas feed from the exhaust manifold 106 to the turbocharger 108.

100151 The turbochargcr 108 includes a turbine 112. The turbocharger 108 also includes a compressor 114 mechanically coupled to the turbine 112. The turbine 112 of the turbocharger 108 is provided in fluid communication with the turbocharger inlet line 110. The turbine 112 is configured to receive the exhaust gas feed from the turbocharger inlet line 110. The turbine 112 is configured to rotate as the exhaust gas passes by and in turn drive the compressor 114. The turbocharger 108 includes a turbocharger outlet line 116 provided in fluid communication with the turbine 112. The turbocharger outlet line 116 is configured to exit the exhaust gas feed from the turbine 112 to atmosphere or an aftertreatinent system (not shown) of the engine system 100. A person of ordinary skill in the art will appreciate that the turbocharger 108 described herein is exemplary. Any other known turbocharger may also be utilized.

100161 A bypass line 118 is provided in fluid communication with the exhaust manifold 106 or the turbocharger inlet line 110 and the turbocharger outlet line 116. In another embodiment, the bypass line 118 may be fluidly connected to the exhaust manifold 106 or the turbocharger inlet line 110 and vented to the atmosphere by means of the turbocharger outlet line 116. A bypass valve 120 or more commonly known as a turbo waste gate valve is provided in the bypass line 118. The bypass valve 120 is mechanically coupled to an actuator 122 configured to urge the bypass valve 120 between an open position and a closed position. Depending on the position of the bypass valve 120, a portion of the exhaust gas feed from the turbocharger inlet line 110 may be directed to the turbocharger outlet line 116 and thus bypass the turbine 112. The working of the actuator 122 will be explained later in detail in connection with Figure 2.

100171 The turbocharger 108 includes a compressor inlet line 124. The compressor inlet line 124 is provided in fluid communication with the compressor 114. The compressor inlet line 124 is configured to provide the airflow to the compressor 114. The compressor 114 is configured to compress the airflow received from the compressor inlet line 124. The compressor 114 is in fluid communication with the intake manifold 104 via an intake line 126. The intake line 126 is configured to provide the airflow from the compressor 114 of the turbocharger 108 to thc intake manifold 104. Additionally, components such as an intercooler or an aftercooler (not shown) may be provided in the intake line 126.

100181 The intakc line 126 includes a control valve 128 in fluid communication with the intake line 126. Referring to Figure 1, an enlarged view of the control valve 128 is illustrated. The control valve 128 includes a valve body 130 defining a chamber 132. The control valve 128 also includes an inlet port 134 in fluid communication with the chamber 132. The inlet port 134 is configured to receive a portion of the airflow from the intake line 126. The valve body 130 also defines a first outlet port 136 and a second outlet port 138 in fluid communication with the chamber 132. The first outlet port 136 is in fluid communication with the actuator 122 via a conduit 140. The second outlet port 138 is configured to vent air to the atmosphere.

100191 The control valve 128 also includes a valve element 142 disposed within the chamber 132 and movcablc between a first position and a second position so as to close or open the second outlet port 138 respectively. In the first position, where the second outlet port 138 is closed, an entire portion of the airflow in the chamber 132 is directed through the first outlet port 136 to the actuator 122. In the second position (or a position between the first and second positions) such that the second outlet port 138 is to some extent open, only a part of the airflow in the chamber 132 is directed through the first outlet port 136 while the remainder is vented to atmosphere. The valve element 142 may be operated by any known methods including, but not limited to, electrical, hydraulic, pneumatic, mechanical or a combination thereof Further, the control valve 128 and/or the valve element 142 may be operated based on a signal received from an engine control module (not shown) of the engine system 100.

100201 Based on the position of the valve element 142, a negative pressure or a positive pressure may be created in the first outlet port 136 and in turn in the conduit 140 and in the actuator 122. For example, when the valve element 142 is in the first position and the entire portion of the airflow passes from the chamber 132 to the first outlet port 136, the positive pressure is created in the conduit 140 and the actuator 122. In another exemplary situation, the valve element 142 may be moved to the second position causing the part of the airflow in the chamber 132 to flow to the second outlet port 138. In this situation, a venturi effect may be created across the first outlet port 136 due to a pressure and velocity of the portion of the airflow through the second outlet port 138, which in turn causes the negative pressure in the conduit 140 and in the actuator 122.

100211 Referring to Figure 2, a cross sectional view of the actuator 122 is illustrated. The actuator 122 may include a housing 202 defining an interior space 204. The interior space 204 may have a generally circular cross section, though may take one of many other shapes. The housing 202 may have a first portion 206 and a second portion 208. The first portion 206 may have a hollow, cup-shaped configuration with a first peripheral edge 210. A first flange 212 may be provided on the first peripheral edge 210 extending inwards and/or outwards with respect to the interior space 204. An air inlet 214 may be provided on a surface of the first portion 206. The air inlet 214 may be attached to the conduit and thus fluidly coupled to the first outlet port 136 of the control valve 128 to receive the portion of the airflow into the interior space 204. The first portion 206 may also include an abutment 216 provided in the interior space 204. The abutment 216 will be explained in detail with respect of Figures 2 to 6.

100221 The second portion 208 may be similar to the first portion 206. The second portion 208 may have a hollow, cup-shaped configuration with a second peripheral edge 218. A second flange 220 may be provided on the second peripheral edge 218 extending inwards and/or outwards with respect to the interior space 204. Unlike the first portion 206, the second portion 208 includes no abutment 216.

100231 A diaphragm 222 may be provided between the first and second flanges 212, 220. More specifically, the diaphragm 222 may be provided in the interior space 204 comprising a first chamber 224 defined by the first portion 206 and a second chamber 226 defined by the second portion 208. The diaphragm 222 is provided between the first and second portions 206, 208 in order to delineate the first and second chambcrs 224, 226 respectively. The diaphragm 222 has a domc shaped configuration having a convex inner portion 228 and a concave outer portion 230. The diaphragm 222 may be provided with a peripheral lip 232 extending outwards from the concave outer portion 230. The diaphragm 222 may be formed of rubber or any flexible polymeric material known to one skilled in the art.

100241 The diaphragm 222 may be provided between the first and second portions 206, 208 in a manner such that the concave outer portion 230 of the diaphragm 222 extends into the first chamber 224. Further, the peripheral lip 232 of the diaphragm 222 is provided in contact with the first and second flanges 212, 220 of the first and second portions 206, 208 of the housing 202 respectively.

Based on the portion of the airflow received in the first chamber 224 through the air inlet 214 and the positive or negative pressure created in the conduit 140, the diaphragm 222 may be configured to move outwardly or inwardly of a neutral position with respect to the first chamber 224. The first chamber 224 may have a lower volume when the diaphragm 222 is in the neutral or inward position compared to an extended or outward position.

100251 An elongate member 234 such as a rod 234 is fixedly attached to the diaphragm 222 and extends into the second portion 208 of the housing 202. The rod 234 may interconnect the diaphragm 222 and the bypass valve 120 such that movement of the diaphragm 222 may adjust the position of the bypass valve 120, thus causing a corresponding change in exhaust gas flow through the turbine 112.

100261 The second chamber 226 may include a spring 236 provided in cooperation with the rod 234 housed within the second chamber 226. The spring 236 may be configured to retain a profile of the diaphragm 222 in the neutral position. During operation of the engine system 100, when the positive pressure is created in the first chamber 224, the diaphragm 222 moves outwards with respect to the first chamber 224 of the housing 202, thus compressing the spring 236.

100271 During assembly of the actuator 122, the first and second flanges 212, 220 cooperate with each other and trap the diaphragm 222 therebetween by trapping the peripheral lip 232 of the diaphragm 222 between the first and second flanges 212, 220. This arrangement may provide an air tight seal between the diaphragm 222 and the first portions 206 of the housing 202. An air tight seal may also be created between the diaphragm 222 and the second portion 208 of the housing 202 though the seal may be less critical. The first and second portions 206, 208 may be secured together using bolts, screws andlor other suitable fasteners. Additionally or alternatively, a suitable adhesive may be used for the coupling of the diaphragm 222 within the housing 202.

10028] In the present disclosure, the abutment 216 is provided in the first portion 206 of the housing 202 of the actuator 122. The abutment 216 may be provided in the interior space 204 of the first portion 206 of the housing 202. The abutment 216 may be provided in a manner such that the abutment 216 corresponds at least partially to the profile of the diaphragm 222 when the diaphragm 222 is in the neutral position. The abutment 216 is positioned immediately adjacent the diaphragm 222 in a manner so as to allow the outward movement of the diaphragm 222 with respect to the first chamber 224 based on the airflow. The abutment 216 is configured to prevent the inward movement of the diaphragm 222 with respect to the first chamber 224 of the housing 202, particularly when the negative pressure is created within the first chamber 224.

Further, a clearance may be provided between the abutment 216 and the diaphragm 222 according to system design and requirements.

100291 Figures 2 to 6 illustrate different configurations of the abutment 216.

The abutment 216 may include one or more members extending inwardly from the first portion 206 of the housing 202. More specifically, the abutment 216 may include one or more members depending axially from the first portion 206 of the housing 202 towards a center of the diaphragm 222 or the first portion 206.

100301 Referring to Figures 2 to 6, the abutment 216 may include a substantially dome shaped configuration having a peripheral flange 238. A dome 240 of the abutment 216 may include one or more cut-outs 242. The cut-outs 242 are configured to maximize the airflow to the diaphragm 222 while the remainder of the abutment 216 restricts movement of the diaphragm 222 inwardly of the neutral position. In one embodiment, as shown in Figure 3, the cut-out 242 may be centrally positioned on the dome 240 of the abutment 216. In another embodiment, as shown in Figure 4, a plurality of projections 402 may extend from a portion of the abutment 216 defining the cut-out 242. Thc plurality of projections 402 may be arranged in a radially inward configuration.

100311 Referring to Figure 5, the dome 240 may include one or more members like fingers 502 extending from diametrically opposite locations on the peripheral flange 238 to a center of the abutment 216. More specifically, four fingers 502 are provided in the abutment 216 and meet at the center of the dome 240. Spaces between the fingers 502 define the cut-outs 242. Referring to Figure 6, the abutment 216 is shown with an additional cut-out 242 at the center of the dome 240 along with the cut-outs 242 formed between the fingers 502.

100321 The peripheral lip 232 may be configured to affix the abutment 216 to the first portion 206 of the housing 202 by any known means like welding, brazing, soldering and so on. In one embodiment, the abutment 216 may be formed as an integral part of the first portion 206 of the housing 202. In another embodiment, the peripheral lip 232 of the abutment 216 may be trapped between the first flange 212 of the first portion 206 of the housing 202 and the peripheral lip 232 of the diaphragm 222. The abutment 216 may be formed of any suitable metal or polymer according to system design and requirements.

Industrial Applicability

100331 The present disclosure relates to the abutment 216 provided within the actuator 122. During operation of the engine system 100, in one exemplary situation, the control valve 128 may be in the closed position. In this situation, the portion of the airflow may be diverted to the first outlet port 136 and further to the first chamber 224 of the actuator 122 from the inlet port 134 of the control valve 128. The airflow may create the positive pressure in the first chamber 224.

The airflow in the first chamber 224, due to its increased pressure, may urge the diaphragm 222 outwardly, so as to move further into or towards the second chamber 226. Further, the movement of the diaphragm 222 causes the movement of the rod 234 which in turn causes the selective operation of the bypass valve houscd in thc turbocharger 108. It should be notcd that in this exemplary situation, the abutment 216 does not restrict the movement of the diaphragm 222.

100341 In another exemplary situation, when the control valve 128 may be in the open position, the negative pressure may be created in the first chamber 224 of the housing 202. The negative pressure may urge the diaphragm 222 to move inwards into the first chamber 224 either from the neutral position or the outward position. Tn doing so, the diaphragm 222 may come in contact with the abutment 216 positioned adjacent the diaphragm 222. The abutment 216 prevents inward movement of the diaphragm 222 into the interior space 204 of the first chamber 224. This restriction on the inward movement of the diaphragm 222 may prevent excessive stress and strain in the diaphragm 222 and also prevent rupture of the diaphragm 222.

100351 While aspects of the present disclosure have been shown and described with reference to particular embodiments, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined by the claims.

Claims

Claims What is claimed is: 1. An actuator comprising: a housing defining an interior space; a diaphragm configured to enclose the interior space and being moveablc between a neutral position whcrcat the interior space has a lower volume and an extended position whereat the interior space has a higher volume; an air inlet provided on the housing and configured to provide an airflow into the interior space; and an abutment provided in the interior space and configured to restrict inward movement of the diaphragm beyond its neutral position.
2. The actuator of claim I, wherein the abutment includes one or more members extending inwardly fitm the housing.
3. The actuator of claim 1, wherein the abutment includes a member depending axially ftxm the housing towards a center of the diaphragm.
4. The actuator of claim 1, wherein the abutment includes ibur members equally spaced around the housing and extending inwardly towards a center of the interior space.
5. The actuator of claim 1, wherein the abutment includes one member extending across the interior space.
6. The actuator of claim 6, wherein the interior space has a generally circular cross-section and the member has opposed ends extending from diametrically opposed locations on the housing.
7. The actuator of claim 1, wherein thc abutment includes cut-outs to maximize airflow to the diaphragm while restricting movement of the diaphragm inwardly of its neutral position.
8. The actuator of claim 1, wherein the abutment includes a single cutout positioned towards a center of the abutment.
9. The actuator of claim 1, wherein the abutment has a profile corresponding closely to that of the diaphragm.
10. The actuator of claim 1, wherein the diaphragm has a convex inner portion and a concaved outer portion.
11. The actuator of claim 1, wherein the abutment is made of a metal or a polymer.
12. The actuator of claim 1, wherein the abutment is integral to the housing.
13. The actuator of claim 1, wherein the abutment is a distinct unit disposed adjacent the diaphragm and trapped between a first portion and a second portion of the housing, the first and second portions being delineated by the diaphragm disposed therebetween.Amendments to the claims have been filed as follows Clalins What k cIaimadk: A ni* *tuat tbfl 4mbb', the valve watr; mØti&th.g:.a housing detning an £nteuor sjnee a d'aphragm prowded within the interior space to dcñne a tint cnarnbe and a second chamber within the houmg the aiaphragrn being noseah1c hk'ts.cen a neatiul poSition n which the nteuor space has a first vvtWne and an *ide1.Utwards pdsition in whidi the interior: pac&.ha.s a second volume fhat4s; 1arer than thefirst vohinie; an air inlet pan ided In thud communication with the flrc ehathh the Mr Jei being eorThgi rcd.c:vde at, arIkw into thc imericr an abutment pinvided in the interror pxe and tonflguied te * r.etdot movement ofT the; diaphragm. beyond Us neutral. positton:j an, irwardly dIrection awa> ±i am the extended outwaids puition and 4n elongate member thedly utiached.o the dhipbragrn and o extendin! tnto the second chamber the elongate member being in * I thcatki tth the aitb1y Thr dtttithv of the valve assenthl;y.2. The vt1:ve. aetoiltor.otcThint 1, wherein the abutment includes.one cr more membus exteuding inwardis from the houtng 3. The valve actuator of claim 1, where in the abutment thclude.s a nienther (hpfll4!:;.g i{XiI ftqm the: hdpsitig tow*rd; a center of sh diaphragrm 4. The valve actuator.1 daim 1. wherein tite aliutatent.ineludes hair nietñb&s equalIty spalccd. ithund the b.ousfrg and ext:c.ndin inwardly ±owards. a center of theinieriorspace.S ta' ajuitjr c f jjm v,hcrem the abumeiit intudes one member extenwng. across the intetisr spacc. The rtettnucw of iM:6 her.iit Øie interini: space ha grsilv.CITCUIcW crclss-secnori and tie member h4' oproed ends cxtertding tram di.ameri&ll: opposed ktati*Ons n the hbtisin..7 i'he vafte'*aetmfor of:elaffii 1. wherein the. ahuti eñt. includes cm-mts to.n'aximize ai floss to the diaphragm hde restnetmg mos ement of the di:.a!=thni jnwardly.cEi its n eutr&1 ponww., The aRe actuatci of claim 1.heiein the abutment includes a srn1e ci:aoupc.si:tionS t.Savd a céntØr of: the at 9. The. actuatct f:lS-1.., tvhtS:h(. abttnerjt *ha a hat of the *diaphrm r 10 [he %a1\e actuator at claim I t%herdul the diaphragm ha a cone inner pcrtion.and a noaved nitr portion.11 1k ah e aetratot of claim 1. wherein the abutment i made of a metal or ..po1yme.12. The valve aei:uatcr of claim 1, v1hereih the thutrneit j.s inwgral tt the: heusing 13. The valve ttuttci Qf.fltj 1 wherein tne xhttt1flUit..I.s dO4lfl(4.ttnit.diwa,ed ad!acent the diaphragm and trapped het'een a first portion and second pornon at the housing the first rid second portions being delineated by the diaphragm disposed therehemetn