Abstract:
A slide valve for use in an air intake manifold is disclosed, wherein a durability of the valve and a quality of a seal created while the valve is in a closed position are maximized, and a cost and a weight of the valve are minimized.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a tuning valve and more particularly to a planar slide valve for use in an intake manifold. 
     BACKGROUND OF THE INVENTION 
     Variable geometry intake manifolds for engines are known. In such a manifold, intake air is controlled to different runners from a plenum to provide varying conditions at an inlet port of a cylinder. The plenum may include a plurality of chambers formed therein, wherein each chamber communicates with a separate runner or bank of runners. The chambers may include tuning valves disposed between adjacent chambers to facilitate communication therebetween. The tuning valves are used as a means of managing the pressure wave dynamics within the manifold, thereby influencing the volumetric efficiency of the engine. 
     Prior art tuning valves, typically butterfly valves, may be prone to leakage or permitting undesirable communication to occur across the valve. More specifically, when the butterfly valve is in a closed position, the pressure pulsations exerted on the valve can cause the valve to open slightly or otherwise impinge on existing gaps in the closed valve, wherein a small amount of fluid, such as air, is permitted to communicate therethrough. To overcome this problem, some butterfly valves are produced with elastomeric seals around their periphery in combination with stronger springs to maintain valve position while under load. These additions tend to increase the costs of the assembly with additional materials and the need for more powerful actuation devices. While these sealed tuning valves have resulted in reduced leakage of pressure pulsations and fluid past the valve while in a closed position, there is a continued desire to maximize the robustness of the seal and minimize the cost, weight, and complexity of the valves. 
     Another problem associated with butterfly style tuning valves is that debris may accumulate on the sealing surfaces of the valve. The debris can prevent a full closure of the valve, which is undesirable. 
     Another problem associated with butterfly type valves occurs when part of the valve protrudes into adjacent air flow paths when changing from closed to open position, such as when the valve is positioned close to the runner entry points or critical flow passages, disturbing airflow to the engine and, thus, negatively affecting engine performance. 
     It would be desirable to produce a tuning valve for use in an intake manifold, wherein a durability thereof and a quality of a seal in a closed position are maximized, communication is sufficient when in an open position, and wherein a cost and a weight thereof are minimized. 
     SUMMARY OF THE INVENTION 
     Harmonious with the present invention, a tuning valve for use in an intake manifold, wherein a durability thereof and a quality of a seal in a closed position are maximized, communication is sufficient when in an open position, and wherein a cost and a weight thereof are minimized, has surprisingly been discovered. 
     In one embodiment, an valve for an air intake manifold comprises: a first end plate having a plurality of apertures formed therein; a second end plate having a plurality of apertures formed therein; and an intermediate plate disposed between the first end plate and the second end plate, the intermediate plate having a plurality of apertures formed therein, wherein a position of the intermediate plate is adjustable with respect to the first end plate and the second end plate to facilitate control of a flow through the valve. 
     In another embodiment, a valve for an air intake manifold comprises: a first end plate having a plurality of apertures formed therein, wherein the apertures are surrounded by frames, the frames having a first wall, a second wall, and a pair of side walls, wherein the side walls are sloped from the first wall to the second wall; a second end plate having a plurality of apertures formed therein, wherein the apertures are surrounded by frames, the frames having a first wall, a second wall, and a pair of side walls, wherein the side walls are sloped from the first wall to the second wall; and an intermediate plate disposed between the first end plate and the second end plate, the intermediate plate having a plurality of apertures formed therein, a plurality of first members formed thereon, and a plurality of second members formed thereon, the first members adapted to receive the frames formed on the first end plate, the second members adapted to receive the frames formed on the second end plate, wherein a position of the intermediate plate is adjustable with respect to the first end plate and the second end plate to facilitate control of a flow of fluid through the valve. 
     In another embodiment a valve for an air intake manifold comprises: a first end plate having a plurality of apertures formed therein and a first channel formed on an inner surface thereof; a second end plate having a plurality of apertures and a first channel formed on an inner surface thereof, wherein the second end plate is formed integrally with a wall of a plenum of the intake manifold; and an intermediate plate disposed between the first end plate and the second end plate, the intermediate plate having a plurality of apertures formed therein and a central shaft disposed thereon, the central shaft adapted to be received by the first channel formed in the first end plate and the first channel formed in the second end plate, wherein the position of the intermediate plate is adjustable with respect to the first end plate and the second end plate to facilitate control of a flow of fluid through the valve. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above, as well as other objects and advantages of the invention, will become readily apparent to those skilled in the art from reading the following detailed description of a preferred embodiment of the invention when considered in the light of the accompanying drawings in which: 
         FIG. 1  is an exploded perspective view of a slide valve in accordance with an embodiment of the invention; 
         FIG. 2  is a perspective view of the slide valve illustrated in  FIG. 1  in a fully closed position; 
         FIG. 3  is a perspective view of the slide valve illustrated in  FIG. 1  in a fully open position; 
         FIG. 4  is an exploded perspective view of a slide valve in accordance with another embodiment of the invention; and 
         FIG. 5  is an exploded perspective view of a slide valve in accordance with another embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make and use the invention, and are not intended to limit the scope of the invention in any manner. 
       FIG. 1  shows a slide valve  10  in accordance with an embodiment of the invention. The valve  10  is adapted to be disposed in a wall (not shown) dividing adjacent chambers, of a plenum (not shown) of an air intake manifold (not shown). It is understood that the valve  10  can be disposed in other locations as desired. The valve  10  includes a first end plate  12 , a second end plate  14 , and an intermediate plate  16 . The intermediate plate  16  is disposed between the first end plate  12  and the second end plate  14 . It is understood that additional intermediate plates  16  can be disposed between the first end plate  12  and the second end plate  14  as desired. In the illustrated embodiment, the first end plate  12 , the second end plate  14 , and the intermediate plate  16  are substantially rectangular in shape. It is understood that the first end plate  12 , the second end plate  14 , and the intermediate plate  16  may have other shapes as desired without departing from the scope and spirit of the invention. Optionally, a sealing material (not shown) such as a elastomeric seal may be disposed on one or more of the plates  12 ,  14 ,  16 . 
     A first bearing insert  18  is disposed between the first end plate  12  and the second end plate  14  adjacent a first end  20  of the intermediate plate  16 . A second bearing insert  22  is disposed between the first end plate  12  and the second end plate  14  adjacent a second end  24  of the intermediate plate  16 . In the embodiment shown, the plates  12 ,  14 ,  16  and the bearing inserts  18 ,  22  are formed from metal. However, other materials can be used to form the plates  12 ,  14 ,  16  and the bearing inserts  18 ,  22  as desired. 
     A first channel  26  and a second channel  28  are formed on an inner surface  30  of the first end plate  12 . The first channel  26  is adapted to receive a first edge  29  of the first bearing insert  18  and the second channel  28  is adapted to receive a first edge  31  of the second bearing insert  22 . A plurality of spaced apart substantially rectangular shaped apertures  32  is formed in the first end plate  12 . 
     A first channel  34  and a second channel  36  are formed on an inner surface (not shown) of the second end plate  14 . The first channel  34  is adapted to receive a second edge  33  of the first bearing insert  18  and the second channel  36  is adapted to receive a second edge  35  of the second bearing insert  22 . A plurality of spaced apart substantially rectangular shaped apertures  38  is formed in the second end plate  14 . 
     A plurality of spaced apart substantially rectangular shaped apertures  40  is formed in the intermediate plate  16 . The first end  20  of the intermediate plate  16  is adapted to be received in a channel  41  formed in the first bearing insert  18 . The second end  24  of the intermediate plate  16  is adapted to be received in a channel  43  formed in the second bearing insert  22 . 
     To assemble the valve  10 , the intermediate plate  16  is disposed between the first end plate  12  and the second end plate  14 . The first bearing insert  18  is disposed in the first channel  26  of the first end plate  12  and in the first channel  34  of the second end plate  14 . The second bearing insert  22  is disposed in the second channel  28  of the first end plate  12  and in the second channel  36  of the second end plate  14 . The first end plate  12  and the second end plate  14  are then fastened by any suitable means to form the valve  10 . The valve  10  is then disposed in a desired position, such as in the wall dividing adjacent chambers of the plenum of the air intake manifold, for example. It is understood that the valve  10  can be disposed in other locations as desired. 
     In operation, the valve  10  is movable between a closed position as shown in  FIG. 2  and an open position as shown in  FIG. 3 . It is understood that the valve  10  can be moved to intermediate positions as desired. While the valve  10  is in an open position, the apertures  32 ,  40 ,  38  respectively formed in the plates  12 ,  16 ,  14  are aligned, and a maximum amount of a fluid such as air, for example, is permitted to flow through the valve  10 . While the valve  10  is in an intermediate position, the apertures  32 ,  40 ,  38  respectively formed in the plates  12 ,  16 ,  14  are partially offset from each other, and an intermediate amount of the fluid is permitted to flow through the valve  10 . While the valve  10  is in a closed position, the apertures  32 ,  40 ,  38  respectively formed in the plates  12 ,  16 ,  14  are completely offset from each other, and the flow of fluid through the valve  10  is militated against. While the valve  10  is in a closed position, since the apertures  32 ,  40 ,  38  respectively of adjacent plates  12 ,  16 ,  14  respectively are completely offset from one another, any fluid that flows between adjacent plates  12 ,  16 ,  14  respectively is caused to flow on a tortuous path through the valve  10 . The tortuous path creates high impedance against any such fluid flowing through the valve  10  while in a closed position. Accordingly, the flow of such fluid through the valve  10  is militated against. If the sealing material is disposed on one or more of the plates  12 ,  14 ,  16 , a quality of a seal facilitated by the closed valve  10  is maximized. 
     An actuating means (not shown), such as an electric actuator, for example, is operatively coupled to the intermediate plate  16 . The actuating means receives a signal from a source (not shown), and causes an appropriate movement of the intermediate plate  16 . If additional fluid flow through the valve  10  is desired, the intermediate plate  16  is caused to move toward the open position. If less fluid flow through the valve  10  is desired, the intermediate plate  16  is caused to move toward the closed position. The first bearing insert  18  and the second bearing insert  22  militate against the flow of the fluid around the first end  20  of the intermediate plate  16  and the second end  24  of the intermediate plate  16 . As additional fluid is caused to flow through the valve  10 , the fluid is caused to flow through an appropriate runner to a cylinder head. 
     As the valve  10  opens and closes, the plates  12 ,  16 ,  14  are caused to slide relative to one another. As the plates  12 ,  16 ,  14  slide, contact between the plates  12 ,  16 ,  14  dislodges unwanted debris, such as sludge or ice, for example, from the plates  12 ,  14 ,  16 . As a result, the buildup of unwanted debris on the valve  10  is militated against, and an efficiency of the valve  10  is maximized. 
     Since the valve  10  operates in a plane, protrusion of the valve  10  into the flow path of the fluid is avoided. Accordingly, a flow rate of the fluid past the valve  10  is maximized. Additionally, pressure pulsations exerted on the valve  10  in the direction of operation of the valve  10  are minimized. Thus, leakage caused by an opening of the valve  10  by the pressure pulsations is minimized. Further, since the thickness of the valve  10  is smaller than other types of valves, packaging and shipping costs associated with the valve  10  are minimized. 
       FIG. 4  shows a slide valve  110  in accordance with another embodiment of the invention. The valve  110  is adapted to be disposed in a wall (not shown) dividing adjacent chambers of a plenum (not shown) of an air intake manifold (not shown). It is understood that the valve  110  can be disposed in other locations as desired. The valve  110  includes a first end plate  112 , a second end plate  114 , and an intermediate plate  116 . The intermediate plate  116  is disposed between the first end plate  112  and the second end plate  114 . It is understood that additional intermediate plates  116  can be disposed between the first end plate  112  and the second end plate  114  as desired. In the embodiment shown, the plates  112 ,  114 ,  116  are formed from metal or plastic. However, other materials can be used to form the plates  112 ,  114 ,  116  as desired. In the illustrated embodiment, the first end plate  112 , the second end plate  114 , and the intermediate plate  166  are substantially rectangular in shape. It is understood that the plates  112 ,  114 ,  116  may have other shapes as desired without departing from the scope and spirit of the invention. Optionally, a sealing material (not shown) such as a elastomeric seal may be disposed on one or more of the plates  112 ,  114 ,  116 . 
     A first channel  126  is formed on an inner surface (not shown) of the first end plate  112 . The first channel  126  is adapted to receive a first surface  127  of a central shaft  128  disposed on the intermediate plate  116 . A plurality of spaced apart substantially rectangular shaped apertures  132  is formed in the first end plate  112 . A frame  134  surrounds each aperture  132  formed in the first end plate  112 . The frame  134  includes a first wall (not shown), a second wall  135 , and a pair of side walls (not shown). The second wall  135  extends outwardly from the first end plate  112  further than the first wall. The side walls are substantially wedge shaped and extend from the first wall to the second wall  135 . 
     A first channel  136  is formed on an inner surface  138  of the second end plate  114 . The first channel  136  is adapted to receive a second surface (not shown) of the central shaft  128  of the intermediate plate  116 . A plurality of spaced apart substantially rectangular shaped apertures  142  is formed in the second end plate  114 . A frame  144  surrounds each aperture  142  formed in the second end plate  114 . The frame  144  includes a first wall  146 , a second wall  148 , and a pair of side walls  150 . The second wall  148  extends outwardly from the second end plate  114  further than the first wall  146 . The side walls  150  are substantially wedge shaped and extend from the first wall  146  to the second wall  148 . 
     The second end plate  114  includes an integrally formed frame  152  that is attached to a gasket  154  disposed on an end wall (not shown) of the plenum. A bushing  156  disposed on the frame  152  is adapted to receive an extension piece  162  formed on the intermediate plate  116 . It is understood that the frame  152  can be formed separately from the second end plate  114  as desired. It is also understood that the second end plate  114  can be attached to other structure as desired without departing from the scope and spirit of the invention. 
     A plurality of spaced apart substantially rectangular shaped apertures  158  is formed in the intermediate plate  116 . The intermediate plate  116  includes a plurality of first members  160  that extend outwardly from a first surface  161  thereof. The first members  160  include a first wall  163 , a second wall  165 , and a pair of side walls  167 . When aligned with the frames  134  of the first end plate  112 , the first members  160  substantially conform to the shape of the frames  134  to form a substantially fluid tight seal therebetween. The intermediate plate  116  includes a plurality of second members (not shown) that extend outwardly from a second surface (not shown) thereof. The second surface is on an opposed side of the intermediate plate  116  from the first surface  161  thereof. The second members include a first wall, a second wall, and a pair of side walls. When aligned with the frames  144  of the second end plate  114 , the second members substantially conform to the shape of the frames  144  to form a substantially fluid tight seal therebetween. The extension piece  162  extends outwardly from a first end  164  of the intermediate plate  116 , and is adapted to be received in the bushing  156  of the second end plate  114 . 
     To assemble the valve  110 , the intermediate plate  116  is disposed between the first end plate  112  and the second end plate  114 . The central shaft  128  disposed on the intermediate plate  116  is received by the first channel  126  of the first end plate  112 . The second lip formed on the intermediate portion  116  is received by the first channel  136  of the second end plate  114 . The first end plate  112  and the second end plate  114  are fastened by any suitable means to form the valve  110 . The valve  110  is then disposed in a desired position, such as in the wall dividing adjacent chambers of the plenum of the air intake manifold, for example. In this situation, the frame  152  would be sealed to the gasket  154  that disposed on the end wall of the plenum in the intake manifold. It is understood that the valve  110  can be disposed in other locations as desired. 
     In operation, the valve  110  is movable between an open position, a closed position, and intermediate positions as desired. While the valve  110  is in an open position, the apertures  132 ,  158 ,  142  respectively formed in the plates  112 ,  116 ,  114  are aligned, and a maximum amount of a fluid such as air, for example, is permitted to flow through the valve  110 . While the valve  110  is in an intermediate position, the apertures  132 ,  158 ,  142  respectively formed in the plates  112 ,  116 ,  114  are partially offset from each other, and an intermediate amount of the fluid is permitted to flow through the valve  110 . While the valve  110  is in a closed position, the apertures  132 ,  158 ,  142  respectively formed in the plates  112 ,  116 ,  114  are completely offset from each other, and the flow of fluid through the valve  110  is militated against. While the valve  110  is in a closed position, since the apertures  132 ,  140 ,  138  respectively of adjacent plates  112 ,  116 ,  114  respectively are completely offset from one another, any fluid that flows between adjacent plates  112 ,  116 ,  114  respectively is caused to flow on a tortuous path through the valve  110 . The tortuous path creates high impedance against any such fluid flowing through the valve  110  while in a closed position. Accordingly, the flow of such fluid through the valve  110  is militated against. If the sealing material is disposed on one or more of the plates  112 ,  114 ,  116 , a quality of a seal facilitated by the closed valve  110  is maximized. 
     An actuating means (not shown), such as an electric actuator, for example, is operatively coupled to the extension piece  162  of the intermediate plate  116 . The actuating means receives a signal from a source (not shown), and causes an appropriate movement of the intermediate plate  116  by moving the extension piece  162 . If additional fluid flow through the valve  110  is desired, the intermediate plate  116  is caused to move toward the open position. If less fluid flow through the valve  110  is desired, the intermediate plate  116  is caused to move toward the closed position. As additional fluid is caused to flow through the valve  110 , the fluid is caused to flow through an appropriate runner to a cylinder head. 
     As the valve  110  opens and closes, the plates  112 ,  116 ,  114  are caused to slide relative to one another. As the plates  112 ,  116 ,  114  slide, contact between the plates  112 ,  116 ,  114  dislodges unwanted particles and debris from the plates  112 ,  114 ,  116 . As a result, the buildup of debris, such as sludge or ice, for example, on the valve  110  is militated against, and an efficiency of the valve  110  is maximized. However, since the side walls of the frames  134  of the first end wall  112  are substantially wedge shaped and the side walls  167  of the first members  160  are substantially wedge shaped, surface to surface contact between the frames  134  and the first end plate  112  is minimized when the position of the intermediate plate  116  is being adjusted. Similarly, since the side walls  150  of the frames  144  of the second end wall  114  are substantially wedge shaped and the side walls of the second members are substantially wedge shaped, surface to surface contact between the second members and the frames  144  is minimized when the position of the intermediate plate  116  is being adjusted. Accordingly, deterioration of the plates  112 ,  116 ,  114  while the position of the intermediate plate  116  is being adjusted is minimized, and the efficiency of the valve  110  is maximized. Though surface to surface contact between the plates  112 ,  114 ,  116  is minimized while the position of the valve  110  is being adjusted is minimized, a substantially fluid tight seal is facilitated between the first end plate  112  and the intermediate plate  116  and the second end plate  114  and the intermediate plate  116  while the valve  110  is in a closed position. 
     Since the valve  110  operates in a plane, protrusion of the valve  10  into the flow path of the fluid is avoided. Accordingly, a flow rate of the fluid past the valve  110  is maximized. Additionally, pressure pulsations exerted on the valve  10  in the direction of operation of the valve  10  are minimized. Thus, leakage caused by an opening of the valve  110  by the pressure pulsations is minimized. Further, since the thickness of the valve  110  is smaller than other types of valves, packaging and shipping costs associated with the valve  110  are minimized. 
       FIG. 5  shows a slide valve  210  in accordance with another embodiment of the invention. The valve  210  is adapted to be disposed between adjacent chambers of a plenum (not shown) of an air intake manifold (not shown). The valve  210  includes a first end plate  212 , a second end plate  214 , and an intermediate plate  216 . The intermediate plate  216  is disposed between the first end plate  212  and the second end plate  214 . It is understood that additional intermediate plates  216  can be disposed between the first end plate  212  and the second end plate  214  as desired. In the embodiment shown, the plates  212 ,  214 ,  216  are formed from metal or plastic. However, other materials can be used to form the plates  212 ,  214 ,  216  as desired. In the embodiment illustrated, the first end plate  212 , the second end plate  214 , and the intermediate plate  166  are substantially rectangular in shape. It is understood that the plates  212 ,  214 ,  216  may have other shapes as desired without departing from the scope and spirit of the invention. Optionally, a sealing material (not shown) such as a elastomeric seal may be disposed on one or more of the plates  212 ,  214 ,  216 . 
     A first channel  226  is formed on an inner surface (not shown) of the first end plate  212 . The first channel  226  is adapted to receive a central shaft  228  disposed on the intermediate plate  216 . A plurality of spaced apart substantially rectangular shaped apertures  232  is formed in the first end plate  212 . A frame  234  surrounds each aperture  232  formed in the first end plate  212 . The frame  234  includes a first wall (not shown), a second wall  235 , and a pair of side walls (not shown). The first wall extends outwardly from the first end plate  212  further than the second wall  235 . The side walls are substantially wedge shaped and extend from the first wall to the second wall  235 . 
     In the embodiment illustrated, the second end plate  214  is formed integrally with a wall  235  of the plenum of the air intake manifold, wherein the wall  235  divides the plenum into adjacent chambers. A plurality of spaced apart substantially rectangular shaped apertures  242  is formed in the second end plate  214 . A frame  244  surrounds each aperture  242  formed in the second end plate  214 . The frame  244  includes a first wall  246 , a second wall  248 , and a pair of side walls  250 . The first wall  246  extends outwardly from the second end plate  214  further than the second wall  248 . The side walls  250  are substantially wedge shaped and extend from the first wall  246  to the second wall  248 . 
     In the embodiment illustrated, the second end plate  214  includes a plurality of protuberances  252  that extend outwardly from a first surface  254  of the second end plate  214 . The protuberances  252  are adapted to receive an outer edge  256  of the first end plate  212 . It is understood that additional or fewer protuberances  252  can extend from the first surface  254  of the second end plate  214  as desired. 
     A plurality of spaced apart substantially rectangular shaped apertures  258  is formed in the intermediate plate  216 . The intermediate plate  216  includes a plurality of first members  260  that extend outwardly from a first surface  261  thereof. The first members  260  include a first wall  263 , a second wall  265 , and a pair of side walls  267 . When aligned with the frames  234  of the first end plate  212 , the first members  260  substantially conform to the shape of the frames  234  to form a substantially fluid tight seal therebetween. The intermediate plate  216  includes a plurality of second members (not shown) that extend outwardly from a second surface (not shown) thereof. The second surface is on an opposed side of the intermediate plate  216  from the first surface  261  thereof. The second members include a first wall, a second wall, and a pair of side walls. When aligned with the frame  244  of the second end plate  214 , the second members substantially conform to the shape of the frames  244  to form a substantially fluid tight seal therebetween. An extension piece  262  extends outwardly from a first end  264  of the intermediate plate  216 . 
     To assemble the valve  210 , the intermediate plate  216  is disposed between the first end plate  212  and the second end plate  214 . The first lip  228  formed on the intermediate plate  216  is received by the first channel  226  of the first end plate  212 . The first end plate  212  and the second end plate  214  are then fastened by any suitable means to form the valve  210 . The valve  210  is then disposed into the plenum between adjacent chambers thereof. It is understood that the valve  210  may be disposed in other locations as desired. 
     In operation, the valve  210  is movable between an open position, a closed position, and an infinite number of intermediate positions as desired. While the valve  210  is in an open position, the apertures  232 ,  258 ,  242  respectively formed in the plates  212 ,  216 ,  214  are aligned, and a maximum amount of a fluid such as air, for example, is permitted to flow through the valve  210 . While the valve  210  is in an intermediate position, the apertures  232 ,  258 ,  242  respectively formed in the plates  212 ,  216 ,  214  are partially offset from each other, and an intermediate amount of the fluid is permitted to flow through the valve  210 . While the valve  210  is in a closed position, the apertures  232 ,  258 ,  242  respectively formed in the plates  212 ,  216 ,  214  are completely offset from each other, and the flow of fluid through the valve  210  is militated against. While the valve  210  is in a closed position, since the apertures  232 ,  240 ,  238  respectively of adjacent plates  212 ,  216 ,  214  respectively are completely offset from one another, any fluid that flows between adjacent plates  212 ,  216 ,  214  respectively is caused to flow on a tortuous path through the valve  210 . The tortuous path creates high impedance against any such fluid flowing through the valve  210  while in a closed position. Accordingly, the flow of such fluid through the valve  210  is militated against. If the sealing material is disposed on one or more of the plates  212 ,  214 ,  216 , a quality of a seal facilitated by the closed valve  210  is maximized. 
     An actuating means (not shown), such as an electric actuator, for example, is operatively coupled to the extension piece  262  of the intermediate plate  216 . The actuating means receives a signal from a source (not shown), and causes an appropriate movement of the intermediate plate  216  by moving the extension piece  262 . If additional fluid flow through the valve  210  is desired, the intermediate plate  216  is caused to move toward the open position. If less fluid flow through the valve  210  is desired, the intermediate plate  216  is caused to move toward the closed position. As additional fluid is caused to flow through the valve  210 , the fluid is caused to flow through an appropriate runner toga cylinder head. 
     As the valve  210  opens and closes, the plates  212 ,  216 ,  214  are caused to slide relative to one another. As the plates  212 ,  216 ,  214  slide, contact between the plates  212 ,  216 ,  214  dislodges unwanted particles and debris from the plates  212 ,  216 ,  214 . As a result, the buildup of debris on the valve  210  is militated against, and an efficiency of the valve  210  is maximized. However, since the side walls of the frames  234  of the first end wall  212  are substantially wedge shaped and the side walls  267  of the first members  260  are substantially wedge shaped, surface to surface contact between the first members  260  and the frames  234  is minimized when the position of the intermediate plate  216  is being adjusted. Similarly, since the side walls  250  of the frames  244  of the second end wall  214  are substantially wedge shaped and the side walls of the second members are substantially wedge shaped, surface to surface contact between the second members and the frames  244  is minimized when the position of the intermediate plate  216  is being adjusted. Accordingly, deterioration of the plates  212 ,  216 ,  214  is minimized, and an efficiency of the valve  210  is maximized. Though surface to surface contact between the plates  212 ,  214 ,  216  is minimized while the position of the valve  210  is being adjusted is minimized, a substantially fluid tight seal is facilitated between the first end plate  212  and the intermediate plate  216  and the second end plate  214  and the intermediate plate  216  while the valve  210  is in a closed position. 
     Since the valve  210  operates in a plane, protrusion of the valve  210  into the flow path of the fluid is avoided. Accordingly, a flow rate of the fluid past the valve  210  is maximized. Additionally, pressure pulsations exerted on the valve  210  in the direction of operation of the valve  210  are minimized. Thus, leakage caused by an opening of the valve  210  by pressure pulsations is minimized. Further, since the thickness of the valve  210  is smaller than other types of valves, packaging and shipping costs associated with the valve  210  are minimized. Moreover, since the second end plate  214  is formed integrally with the wall  235 , the need for additional sealing structure for sealing the second end plate  214  to the wall  235  and the steps associated therewith are minimized. 
     From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions.