Abstract: The presented valve (1) is based on two axially adjustable sleeve-shaped valve seat rings (14, 36) that are associated with locking arrangements in the form of annular armature plates (22, 35) and associate holding coils (24, 36). The valve closure member (39) can be variably adjusted via a position adjustment drive. Said valve closure member has a double function. On the one hand, it acts to move the valve seat rings (14, 26) into locking position and, on the other hand, it acts to control the gas flow.

Abstract: A linkage mechanism for a control valve in a nail gun is provided. The control valve is disposed on a main body of the nail gun. A valve plug of the control valve adjoins to a safety rod of the nail gun. A trigger valve is mounted on the main body and an outer trigger is disposed adjacent to the trigger valve. An inner trigger is pivotably disposed in the outer trigger. An end of a rod member is slidably disposed at a side of the outer trigger and another end of the rod member is connected between the valve plug and the safety rod with an arm. A stopping portion is formed at a middle portion of the rod member. The stopping portion is configured for pressing the outer trigger so as to drive the inner trigger to push the rod member, the arm, the valve plug and the safety rod to move along a nail driving direction of the nail gun. The present linkage mechanism can improve a stability of controlling of nail shooting action and a durability of the nail gun.

Abstract: A pressure reducing valve includes a opening/closing valve between primary and secondary pressure chambers, a diaphragm body, a valve hole through which the secondary pressure chamber is communicatively connected with the atmosphere, a relief valve which opens/closes the valve hole, and a linkage member which links the opening/closing valve with the relief valve so as to open/close in association with each other. The linkage member includes a valve guide having a valve passage through which the primary and secondary pressure chambers are communicatively connected, and a pintle inserted into a pintle hole and guided thereby. The opening/closing valve and the relief valve are provided on lower and upper ends of the pintle, respectively. The valve hole has a common axis with those of the valve passage and the pintle hole. One and the other of the valve guide and the pintle are made of resin and metal.

Abstract: A dispensing valve assembly is configured to control flow from an associated container or like reservoir, and includes a dispensing valve body configured for connection to the associated container. The valve assembly includes a resiliently deformable valve member, positioned within the valve body, for controlling flow therethrough. Selective opening of the valve member is effected by the provision of a reciprocably movable actuation member, positioned generally within the valve body, which can be actuated to bear against and engage the valve member to move the valve member from its closed configuration to its open configuration. An actuation button, provided on the exterior of the valve body, is engageable with the internal actuation member to permit convenient operation of the valve assembly.

Abstract: An intake airflow control mechanism for an engine includes a first valve shaft on which valve elements of intake airflow control valves are fitted in such a manner that the valve elements pivot in accordance with the rotation of the first valve shaft; a second valve shaft on which valve elements of intake airflow control valves are fitted in such a manner that the valve elements pivot in accordance with the rotation of the second valve shaft; an actuator that rotates the first valve shaft, a link mechanism that transmits the rotation of the first valve shaft to the second valve shaft, a stopper that stops the rotation of the second valve shaft when the second valve shaft is in a prescribed rotational position, and a sensor that detects the amount by which the first valve shaft is rotated by the actuator.

Abstract: An exhaust valve assembly includes a valve body, a valve supported by a shaft within the valve body, and an actuator that drives the shaft to move the valve relative to the valve body. A side load feature engages one portion of the shaft to reduce valve chatter by side loading the shaft.

Abstract: The invention relates to an actuating device (10) for shut-off needles in injection molds having needle valve nozzles. The actuating device has at least one lifting element (20), to which at least two shut-off needles (16) may be fixed, and at least one actuating element (30) which is mounted so that it is longitudinally displaceable in a first direction (R1) and which is coupled to the lifting element (20) in such a way that a motion of the actuating element (30) along the first direction (R1) is converted to a motion of the lifting element (20) in a second direction (R2) transverse to the first direction (R1). In order to guide the sliding mechanism in a precise and consistently reliable manner, according to the invention the actuating element (30), which is slid in a guide unit (90) along the first direction (R1), is provided with an additional force-guided element (50).

Abstract: A pinch valve for regulating fluid flow having a close mechanism using push-pull members and an open mechanism using open follower members in order to pinch a sleeve closed and to assist in opening it. In a particular embodiment, a four-bar linkage is employed.

Abstract: Disclosed is a remotely operable top drive safety valve assembly having first and second valve elements. An actuator sleeve moves longitudinally on the main body of the top drive safety valve assembly under the influence of an operating arm. When operating the first valve element, a lock plate is preferably installed over the second valve element stem, and an arm is externally fixed to the stem of the first valve element and is disposed in a cutout in the wall of the actuator sleeve. Movement of the actuator sleeve up and down moves the arm, and thereby moves the first valve element between open and closed positions. When operating the second valve element, the arm on the upper valve element stem is removed, a lock plate is preferably installed over the first valve element stem, an arm is installed on the second valve element stem, and a linkage assembly is installed which operationally engages the second valve element stem arm with the actuator sleeve.

Abstract: A variable fuel admission carburetor is provided including a piston and cylinder that are mated concentrically, and coexist in a carburetor chamber. The cylinder includes a longitudinal slot which allows varying amount of fuel into the carburetor. Through the relative longitudinal movement of the piston in the cylinder, the exposed length of the slot is varied, thereby varying the amount and rate that the fuel enters the chamber.

Abstract: The invention relates to a shut-off fitting comprising a housing which is connected to an adjacent pipeline in a pressure tight manner, the diameter of said pipeline defining a tubular passage in the housing. Said fitting also comprises at least one closing body which can be displaced between an open position and a closed position. The inventive shut-off fitting is characterized in that the at least one closing body can be displaced by an articulated mechanism, by means of an actuator which can be vertically displaced in relation to the flow direction, in such a way that it is arranged outside the tubular passage in its open position. The closing body has a contour which is adapted to the contour of the tubular passage, in the open position, and is located on the tubular passage in a radially sealing manner.

Abstract: A valve mechanism having at least one movable valve member for sealing of a valve opening in a housing. Movements of the individual movable valve members are accomplished essentially parallelly to, and perpendicularly to, the seat surface of the valve during the opening and closing of the valve. In order to achieve high forces and low wear in the movement carried out with aid of a slot guide which guide serves to transmit forces during, and in the direction of, the opening and closing, the slot guide comprises slots which are formed in a drive plate, which slots cooperate with and overlap complementary slots in the movable valve members.

Abstract: An elbow fluid flow valve exhibiting reduced flow loss and including a body having a specified shape and size and defining a short radius associated with an elbow shaped fluid passageway characterized by a first fluid flow inlet and a second fluid flow outlet. A cover secures over the valve body, and such that a generally sleeve shaped annulus is defined therebetween. A light-weight and linearly translatable sleeve is mounted exteriorly of the valve body and within the intermediately defined annulus. The sleeve is operable to be displaced between a first location permitting fluid flow to the outlet and a second location interrupting fluid flow.

Abstract: A fuel metering apparatus provides a carburetor; a fuel float control, a fuel metering assembly and a rocker arm assembly. The rocker arm is mechanically linked to and is operated by an accelerator pedal. Its position determines the size of a gap between a fuel metering tube and the metering piston, of the fuel metering assembly, to adjust a gap between the metering piston and a metering tube, which determines the precise rate of fuel flowing into the carburetor's air stream.

Abstract: An opening/shutting apparatus for flow control includes a damper door that opens/shuts a fluid channel of an interior of a duct, a knob that adjusts the damper door, a link coupled to an end of the damper door, and a rod hinged with both the knob and the link, the rod transmitting a rotational force of the knob to the link. The rod is configured to have a hinged structure where one end thereof is hinged with the link and the other end is hinged with the knob, and, when the interior of the duct is hermetically sealed, a rotational center of the knob is placed on a straight extension line connecting respective hinged points of the rod.

Abstract: An actuator element suitable, for example, for actuating a rotatable disk or a flap valve shaft. The actuator includes a housing, a drive situated in the housing, and at least one position detector, in which a movably mounted piston rod in the housing is operatively connected to the drive for exerting a force effect, and in which the position detector includes at least one stationary Hall sensor and at least one magnet movable relative to the Hall sensor such that the magnet produces a magnetic field for generating a magnetic flux.

Abstract: A flow control valve system has a housing that defines a flow path, a throttle element disposed in the flow path, and a linkage assembly coupled to the throttle element and oriented substantially outside the flow path. With such an orientation, the linkage assembly has minimal effect on a pressure gradient or pressure drop within the flow control valve system. As such, the linkage assembly allows the flow control valve system to deliver fluid from a fluid input channel to a fluid output channel at a relatively large volume flow rate.

Abstract: A drain pipe dispenses waste water from the vehicle. The drain pipe has a circumferential slot and a gate collar around the drain pipe over the slot. A gate valve is coupled to the gate collar. A gate reciprocable between a closed and open position is provided. A drive rod coupled to the gate with a free end is formed with a C-shaped hook. A pivot bolt is provided. The lever is rotatably supported on the pivot bolt. A handle has an intermediate extent. The intermediate extent is slidably received in the C-shaped hook whereby moving the handle toward the drain pipe closes the gate valve and moving the handle away from the drain pipe opens the gate valve.

Abstract: The valve (1) has a valve casing (2), a cone (4) with a shaft (40) emanating from the Cone (4), and a seat (20). The valve has a control element (3) for moving the cone (4) to and from the seat (20). The control element (3) comprises a first leg (30) located outside the valve casing (2) and a second leg (31) which is at least partially located inside the valve casing (2). The second leg (31) passes through and is firmly attached to an elastic and springing-back wall section (21) on the valve casing (2) which faces the seat (20) and its lower end (310) merges into the shaft (40) via a joint (5). When the valve is closed the springing-back wall section (21) presses the cone (4) against the seat (20) via the second leg (31) and the shaft (40).

Abstract: A fluid diaphragm valve and interconnected pilot valve apparatus for control flow of fluid discharge from a pressurized fluid distribution system. The apparatus has a primary valve with an inlet adapted to receive fluid under pressure, and an outlet adapted to discharge fluid to an outlet conduit. A diaphragm chamber is provided in the primary valve that is responsive to fluid pressure controlled by a pilot diaphragm valve. Upon release of fluid pressure in the pilot diaphragm valve, the primary valve allows passage of fluid to the outlet conduit. Bleed fluid from the pilot valve is also discharged into the outlet conduit and is thus saved for use. Upon closure of the pilot valve, a bleed port in the primary diaphragm in the primary valve allows repressurization and seating of the primary diaphragm, thus terminating fluid flow through the primary valve.

Abstract: An operating mechanism is provided and has an operating lever, an adjusting lever, and a valve element that is rotatably disposed in a channel, wherein the adjusting lever is connected with the valve element via a shaft. A coupling element is provided for interconnecting the positions of the operating lever and the adjusting lever. The distance of the pivot axis of the adjusting lever from a connection of the coupling element with the adjusting lever is variable as a function of the position of the adjusting lever.

Abstract: This invention discloses an ornamental fountain wherein a fountain nozzle is made to discharge a pressurized stream of liquid, and a shutter prevents or allows the stream to exit.

Abstract: A diaphragm valve for shutting off milk flow through a claw (13) of a vacuum driven milking machine has, in a preferred embodiment, a lever (5) linked (6), outside the milk flow, to the diaphragm (4), thereby avoiding any bushings which are prone to leakage. The lever (5) can be swung manually to a position holding the diaphragm away from its seat thereby permitting milk flow. In the automatically closing embodiments, the lever is swung in this case against the bias of a spring (7) and is retained in this open position if the suction force acting on the diaphragm (4) and the link (6) is sufficient to overcome the bias of the spring (7), which will be the case when there is normal milk flow through the valve.

Abstract: A method and apparatus for translating linear movement into rotational movement in an actuator configuration is provided. For example, a rotary actuator assembly includes a housing having a central bore. A piston is disposed within the housing and is linearly movable along an axis of the central bore. A rolling diaphragm is disposed within the housing and coupled with the piston. A bifurcated linkage having an end flange couples with the piston and the rolling diaphragm. An articulatable coupling further connects the bifurcated linkage with a rotating linkage. A spring button, which can be cone shaped, is disposed within the housing. A compression spring is retained between the end flange of the bifurcated linkage and the spring button, for example, by a threaded rod and nut. The assembly is arranged such that when force is applied to the rolling diaphragm the bifurcated linkage is linearly transported, which results in the pivoting of the rotating linkage about a pivot point.

Abstract: A solenoid-operated valve which has, between a moving element operated by an electromagnetic force and a valve element, a displacement converting mechanism for increasing or decreasing a displaced amount of the valve element relative to a displaced amount of the moving element, or a force converting mechanism for increasing or decreasing a driving force of the valve element relative to a driving force of the moving element. This solenoid-operated valve can reduce power consumption because it changes the displaced amount or the driving force of the valve element with a simple structure.

Abstract: An amplifying linkage for rotational actuation between a driving shaft and a driven shaft wherein the driving shaft rotates through a first rotary angle and the driven shaft rotates through a second and different rotary angle. The driven shaft is provided with a first lever arm having a slot formed in its distal end, and the driving shaft is provided with a second lever arm having a pin protruding in a direction parallel to the axis of the driven shaft. The shafts are offset such that the pin is receivable and slidable in the slot. Rotation of the driving shaft through a first angle causes the driven shaft to be rotated through a second angle. The first lever arm is shorter than the second lever arm, so that the second angle is always greater than the first (angular rotation is amplified). The invention is particularly useful in adapting a four-pole torque motor to the actuation of an Electric Throttle Control throttle valve for an internal combustion engine.

Abstract: A valve has a valve body having a passage including a hole in which gas flows. A valve disc is provided for closing the hole, and an actuator is provided for operating the valve disc. An emergency cutoff device is provided so that the valve disc closes the hole in an emergency when electric power supply is cut off.

Abstract: A control handle support and valve linkage assembly for use in a lift truck or like vehicle is provided. The assembly includes a first stationary bracket and a second bracket that pivots relative to the first bracket. At least one, and preferably an array of control handles are coupled to the second bracket. A seat deck on the lift truck includes an actuator for engaging a member projecting from the second bracket. When the seat deck is in the closed position, the second bracket is kept in a first, retracted position, and hence, the control handle(s) are kept close to and within the comfortable reach of an operator seated in the adjacent seat. Then, when the seat deck is opened, such as when the operator desires to access a battery compartment or the like, the second bracket, and hence, the control handle(s) automatically and simultaneously pivot or rotate relative to the first stationary bracket. This moves the control handles out of the path of travel of the seat deck to avoid creating any interference.

Abstract: A valve actuator includes two parallel tracks in each of which a slider block is disposed to slide with a pivot pin and nut carried between the slider blocks; a valve stem engaging member is provided with an arm terminating in a sleeve in which a pin having an eccentrically shaped central portion is disposed; from each slider block, an arm extends to connect to an end of the pin in the sleeve; a set screw is employed to fix the position of the pin once the angular position of the arms is set to obtain the optimum mechanical advantage.

Abstract: A gate valve (20) for a semiconductor processing system includes a base frame (28) configured movable along a guide (26) to move toward and away from a valve seat (22), which surrounds an opening portion (14). A first stopper (56) is disposed at the upper end of the guide (26), for defining the movement limit of the base frame (28) on the valve seat (22) side. A swing frame (34) is rotatably attached to the base frame (28), and has an upper end connected to a valve plug (24). The swing frame (34) is connected to the base frame (28) by a link mechanism (36), which can bend and stretch while flexing an intermediate portion, and by a spring and damper member (46). The intermediate portion of the link mechanism (36) has a mediation member (38) connected to a reciprocation rod (54) of an air actuator (52).

Abstract: A butterfly damper has a plurality of blades movable between an open and a closed position in response to an operating means attached to the blades and attached to an actuating means. A shaft rotatable about its axis in response to said actuating means has crank arm means attached to it and to said blades, to open and close said damper in response to rotation of said shaft. Connector arm means are pivotally connected to crank arms and pivotally connected to said blades at pivot point locations such that the pivot points of said pivotal connections are over center of the plane of the axis of said shaft when the blades are in the closed position.

Abstract: A fluid pump is provided that produces an outflow of fluid that is not proportional to the speed of the input drive. Thus, the fluid pump can be tuned to provide a substantially constant outflow of fluid irrespective of the speed of the input drive. The fluid pump also provides fluid outflow when the rotational direction of the input drive is reversed.

Abstract: A clutch arm centering device is disclosed. The device is mounted on a clutch using to operate piston valves on a crane or other heavy machine. The piston valves may be operated using a valve arm which has two operative positions and a neutral position between the two operative positions. A clutch arm of the clutch is linked to valve arm to allow the valve arm to be manipulated by a remote control coupled to the clutch. As parts of the linkage between the clutch arm and the valve arm wear, the centering device biases the clutch arm to a central position which corresponds to the neutral position of the valve arm, thereby avoiding problems of understroking and overstroking which arise in the prior art.

Abstract: A valve, especially a switch-over valve for large channel cross sections, is provided. A wing is pivotably mounted in a housing having channel connections. A fixating lever assembly provides for movement of the wing and includes a fixating lever and at least one link rod, one end of which is pivotably connected with the fixating lever while the other end is pivotably connected with the wing. A respective driver passes through and is mounted on opposite side walls of the housing. An inner end of each driver is connected to the fixating lever of a given one of the assemblies. A rotary drive mechanism engages an outer end of each driver.

Abstract: An electrically controllable valve comprising at least one input port (13) and one or more output ports (12, 14), at least one sealing means (17, 18) being arranged to control the flow of a fluid between said input port and at least one of said output ports, said valve comprises one or more piezo-electric actuators (26) arranged to control the state of said sealing means, whereby the flow of fluid through said valve may be electrically controlled.

Abstract: A valve system for fluid pipes is disclosed. This valve system is designed to be operable using pneumatic pressure or using another means, such as a valve control lever or fluid pressure, in place of pneumatic pressure and is designed to be controlled easily and precisely. The valve body (20) is thus movable within the passage (13) while minimizing frictional force between the valve body and the valve housing (10). The valve control lever (50) is operated in conjunction with the annular guide groove (24) formed on the circumferential external surface of the pressure actuated flange (25) of the valve body (20). In such a case, the linear moving direction and moving distance of the valve body is determined by the rotating direction and rotating angle of the lever (50). The valve system of this invention also has a rotor (40) used for centrifugally forcing the fluid introduced into the passage. A fluid guide rod (45) axially extends along the center of the passage, thus guiding the flow of fluid.

Abstract: To be able to reduce the size of a drive part and, as a result, to achieve the reduction in size and the lowering of manufacturing cots of a gate valve. An open/close mechanism is configured from a turning pair only. This open/close mechanism is configured from a first swing link, second swing link and coupling link. The first swing link is driven by a rotation cylinder to perform a swinging motion. The second swing link is connected to a drive shaft and performs a swinging motion with the drive shaft as its axis. The first swing link and second swing link are coupled by the coupling link. When the rotation cylinder is driven, whereby the first swing link is caused to swing, the coupling link is vertically driven whereby the second swing link is caused to swing. As a result, a valve, connected to the second swing link, swings and the opening and closing operation of the flow path port is performed.

Abstract: The invention relates to a heating, ventilation and/or air conditioning apparatus that includes a control device and a flap controlled by the control device. The control device includes a control member and a kinematic control linkage of the direct-coupling type arranged between the control member and the flap. The kinematic linkage includes a cable fixed close to its ends and at least one elastic element arranged in such a way as to confer deformability by flexing the kinematic linkage when the flap is at an end stop position. The provided flexibility makes it possible to dispense with the setting-up of the control device and reduces the spring effect in the kinematic linkage.

Abstract: A valve, especially a switch-over valve for large channel cross sections, is provided. A wing is pivotably mounted in a housing having channel connections. A fixating lever assembly provides for movement of the wing and includes a fixating lever and at least one link rod, one end of which is pivotably connected with the fixating lever while the other end is pivotably connected with the wing. A respective driver passes through and is mounted on opposite side walls of the housing. An inner end of each driver is connected to the fixating lever of a given one of the assemblies. A rotary drive mechanism engages an outer end of each driver.

Abstract: A damper assembly in which the position of the damper blades is controlled by an electric powered actuator. The powered actuator rotates a threaded lead screw shaft attached to an operator means attached to the damper blades of the damper, which causes the damper blades to open and close or be positioned somewhere in-between. The actuator can be controlled by sensors in a remote location. The actuator allows the damper to be modulated to set up pressure differentials and to be closed well in advance of oncoming smoke, fire, or other detected toxic fumes. There are a variety of nuts and gear arrangements coacting with the lead screw to drive the operator.

Abstract: A linkage assembly including a crank arm, first and second elongated links, and first and second springs. Ends of the links are adjacent one another and overlap. The first spring is held within this overlapping portion. The second spring is held about an unoverlapped portion of the second link. In a neutral position, the first and second links are balanced in force. In an open position, the first and second links are moved away from one another, causing the second link to be less compressed than the first link. In a back pressure position, the first and second links are moved toward one another, causing the first link to be less compressed than the second link. The first and second springs are held such that they are balanced in the neutral position and provide a restorative force in the open and back pressure positions.

Abstract: A valve actuator includes two parallel tracks in each of which a slider block is disposed to slide with a pivot pin and nut carried between the slider blocks; a valve stem engaging member is provided with an arm terminating in a sleeve in which a pin having an eccentrically shaped central portion is disposed; from each slider block, an arm extends to connect to an end of the pin in the sleeve; a set screw is employed to fix the position of the pin once the angular position of the arms is set to obtain the optimum mechanical advantage.

Abstract: Disclosed is a differential valve specifically a cabin air discharge valve for use in the cabin pressure regulating system of an airplane. The valve has two valve stages for closing a valve port including a smaller first stage and a larger second stage. The first and second stages are connected to a common drive gear mechanism that actuates the smaller first valve stage separately and prior to actuating the larger second valve stage. Also disclosed is a method for regulating cabin pressure by means of the differential valve.

Abstract: A mechanical dual temperature damper closing mechanism having a primary link that separates when the ambient temperature reaches approximately 74° F., closing the damper. The new mechanism provides a reliable means for reopening the damper to allow airflow for the control of smoke spread. A secondary link is engaged within the new mechanism to reopen the damper. When the ambient temperature reaches 180° F. the secondary link separates, closes the damper such that it cannot be reopened.

Abstract: An electromagnetically operating device for actuating a valve comprises a single solenoid cooperating with an armature which cooperates by a crank system with a shaft which, in turn, is cooperating by a crank system with a valve. The fully open position and the closed position of the valve is defined by the stretched position or the folded position of its crank system. The armature, in the fully open position and in the closed position of the valve, is substantially in the same end position so that the crank system during a valve stroke moves through a dead center position.

Abstract: A hydrant valve assembly including a spool member having at least one spool seal which is at times under extremely high pressure tending to cause the seal to be displaced from an associated recess, the spool member forming venting passages in the seal recess to alleviate seal pressure, the invention also including a new wet pipe design and a new collar design.

Abstract: The present invention relates to an apparatus for controlling the supply of intake air to a vehicle, incorporating a control unit which is arranged to indicate and initiate supply of intake air to at least three intake air regions in the vehicle which usually comprise a defroster region, a panel region and a floor region. The apparatus incorporates a control arrangement which is designed, depending on the setting of the control unit, to control dampers (15 A-C) which are situated in ducts which lead to the intake air regions. The control arrangement incorporates a cam arrangement designed to act upon an arm (14 A-C), arranged for each inlet air region, for variable setting of at least one of the dampers (15 A-C) between an open and a closed position.

Abstract: Apparatus for coordinating the positions of valves in a pair of air flow passages along a jet engine nacelle to control two rotary valves from a single linear actuator. Each of the valves is of a ball type which is rotatable within a housing to achieve variable flow control in accordance with the particular shape of the opening through the rotatable valve member which varies with valve member rotation. The valve member bore shape may differ for the two valves, as well as the angle of the linkage between the linear actuator and each valve, to achieve different flow control relationships for the two valves from the single actuator armature. Each valve incorporates a pressure balancing member at the inlet seal of the valve which results in a reduction of the force of the seal element against the rotatable valve member when the valve is in the closed position, thereby reducing the torque required to rotate the valve out of the closed position.

Abstract: A bottom valve assembly is provided for a tank car having a top portion, a bottom portion, and a manway disposed in the top portion. The assembly includes a valve seat disposed in the bottom portion of the tank car and defining an outlet opening and a plug moveable between closed and open positions relative to the outlet opening. In the closed position, the plug is disposed against a seat to form a substantially liquid-tight seal. The assembly also includes a link pivotally mounted to the manway, operating linkage coupled to the plug and pivotally coupled to the link, and a lever fixedly secured to the link. Movement of the lever causes the plug to be moved between the open and closed positions. The assembly may also include a latch for preventing movement of the plug from the closed position and a secondary linkage for moving the latch and to provide an indication at the manway of the plug position.

Abstract: A swing gate valve for closing a lateral discharge opening in an elongated conduit includes a swing gate shaped to fit around the exterior of the conduit in an open position adjacent the lateral opening. A pair of pivotable swing arms are connected to the swing gate on opposite sides of the conduit, and are operated by an air ram to swing the gate to move it to a closed position over the discharge opening to an open position.