Abstract: The invention relates to a closure device (28) for a filter unit (1) for the mutual and releasable insertion into a return air duct or exhaust air duct (2) of a barrier system (3), comprising a main body (30), an opening (6) in the main body (30) that can be peripherally bounded by an annular seal (11), a lid (10) that can be switched between an open position in which the opening (6) is open and a closed position in which it bears in a sealing manner against the annular seal (11) in order to selectively open and close the opening (6) and that has passing through it an imaginary longitudinal axis (A), wherein the lid (10) is connected in an articulated manner to the main body (30) so as to be able to pivot by means of at least one rotary articulation (40) through which there passes a pivot axis (S).

Abstract: A valve for throttling gas flow from a semiconductor processing tool includes a valve body. A shaft extends through the valve body. The shaft defines an internal cavity and a first opening communicating with the internal cavity. A first deflector is positioned on the shaft proximate the first opening and directed at a first interface between the shaft and the valve body. A method for throttling gas flow from a semiconductor processing tool includes providing a gas in an internal cavity defined in a shaft of a valve and directing the gas through an opening defined in the shaft and communicating with the bore toward an interface between the shaft and a valve body of the valve supporting the shaft.

Abstract: An eccentric butterfly valve, suitable for high-pressure fluids, in which: even if a dimensional error among components is large, the seat ring is aligned with the disk while sealability between the seat ring and the body is ensured; for either pressure, positive pressure or counter pressure, the seal surface pressure between the disk and the seat ring is ensured to achieve sealability; and a continuous seal portion is ensured between the body and the seat ring, thereby reliably inhibiting fluid leakage, and a method of manufacturing the eccentric butterfly valve. A tapered surface 31 formed on a seat ring 20 and a step portion 30 formed on a body 2 are opposed to each other. With a corner portion 35 of the step portion 30 on a tapered surface 31 side digging into the tapered surface 31, an annular seal portion 33 is formed on an opposed plane between the body 2 and a seat ring 6.

Abstract: Technologies are generally described for valve assemblies that include a valve body whose inner wall defines two ports and a controllable flow path that extends along the inner wall between the two ports of the valve body. Each port may be fitted with a corresponding gasket. A rotatable member disposed in the controllable flow path of the valve body may include a hemispherical-shaped body with a substantially flat disk-shaped surface portion, and a seal ridge formed about a perimeter of the substantially flat disk-shaped surface portion. During opening and closing operation, the seal ridge may be selectively engaged with either one of the gaskets reducing an initial contact surface, and thereby reducing friction between the rotatable member and the gaskets.

Abstract: A ceiling vent assembly has a frame that is open at its top and bottom and a pair of louvers pivotably mounted in the frame such that each louver pivots between an open position and a closed position relative to the frame. Each louver has a pivot end, wherein the pivot end is located adjacent to but spaced apart from the pivot end of a second louver of the pair of louvers. The ceiling vent assembly has a sealing mechanism with a flange extending from the pivot end of each louver of the pair of louvers, wherein the flange from the first louver contacts the flange from the second louver in a space between the louvers such that the sealing mechanism reduces the flow of air through the space when the first and second louvers are in either the open or closed positions.

Abstract: An eccentric butterfly valve that maintains high sealability when closed even when a high-pressure fluid is oriented in either direction of a forward flow or backflow. The valve includes a disk (23) axially supported at an eccentric position via a stem (22) inside a body (21). The disk is provided to a seat ring (24) fixed with a seat retainer (25) so as to be hermetically sealable. A flexible part is formed on an inner diameter side of the seat ring, and a spring member is mounted between the flexible part and the seat retainer. In the spring member, a load increases substantially in proportion to the magnitude of tilt of the flexible part when the disk is displaced to a seat retainer side. When the flexible part is elastically deformed, the spring member is elastically deformed in a state where contact with the seat retainer is avoided.

Abstract: A valve disk of a double eccentric butterfly valve having boss sections (3, 4) for accommodating a stem (8) and rib sections (6, 7) each extending toward outer edge portions of the valve disk in a direction intersecting a stem (8) from the boss sections are provided on a surface on one side of a disc (2), and each of the ribs respectively excluding the boss sections is provided such that a height from a surface (2a) of the disc on the side on which a distance to an end on the edge portion side of the valve disk is longer than that on the side on which a distance to an end on the edge portion side of the valve disk is short when the heights are respectively compared at positions spaced an equal distance apart from a stem center axis (20), and the butterfly valve.

Abstract: A resilient seal includes an annular body portion and a seating surface defined by the annular body portion and configured to interface with a seat of a subsurface safety valve. The resilient seal further includes a plurality of sealing surfaces defined by the annular body portion. Each sealing surface of the plurality of sealing surfaces is positioned to interface with a flapper of the subsurface safety valve in a closed position of the flapper of the subsurface safety valve. Additionally, the resilient seal includes at least one annular channel defined by the annular body portion between adjacent sealing surfaces of the plurality of sealing surfaces.

Abstract: A valve includes a flap, a tubular valve body defining a passageway, and a guiding device to guide the flap relative to the valve body for pivoting the flap relative to the valve body about a pivot axis between a closed position and an open position of the passageway. The guiding device comprises a pin traversed by the pivot axis and comprising a body with a base and, opposite the base, a free end resting against the valve body. The pin also comprises two lugs each protruding from the base in a direction opposite to the free end, the two lugs defining between them a slot, wherein an edge of the flap is received. The valve further comprises at least one member, connected to the flap, and which presses one of the lugs of the pin against the flap.

Abstract: Exemplary embodiments are directed to butterfly valves, generally including a body assembly. The body assembly generally includes a body, a disc rotationally disposed inside an opening of the body, a bearing disposed inside the disc and the body, and a stem passing through the disc, the bearing and the body. The bearing generally includes an internal bearing edge. The stem generally includes an external stem edge to engage the internal bearing edge to prevent stem blowout from the body. Methods of assembling and positioning a butterfly valve are also provided.

Abstract: Systems provide and methods utilize a multi-bar linkage in conjunction with an actuator to provide mechanical advantage which increases as a control surface moves towards the extremes of its operating envelope.

Abstract: Sealing arrangement of a fluid system for use with cryogenic media, said arrangement comprising a sealing ring in which a first system component is connected to a second system component by means of the sealing ring which sealing ring further has a first sealing surface which sealingly engages the first system component and the sealing ring has a second sealing surface which sealingly engages the second system component which first sealing surface and second sealing surface of the sealing ring are designed such that the first and second system components in the area of the sealing surfaces extend radially within the sealing ring in a section plane which extends parallel to the direction of contraction, and the sealing ring when exposed to cold, contracts thermally to a greater extent than the first system component and the second system component.

Abstract: A vacuum valve placed between a vacuum vessel and a vacuum pump to adjust a valve opening degree using an operating fluid includes a packing mounted in a recessed groove of a piston. The packing is provided with a contact portion on a radially inner side and a contact portion on a radially outer side, and a slide-contact portion contacting with an inner peripheral surface of a cylinder. A portion between the contact portion and the slide-contact portion has a thin thickness.

Abstract: A butterfly valve has a housing that has an annular valve seat and a butterfly disk that has an annular valve seat. At least one of the valve seats is a spring seat that has an annular mounting portion and an axially opposite annular engagement portion. The engagement portion is configured to contact the other valve seat and resiliently deform radially under hoop stress caused by the contact as the butterfly disk moves to the closed position. The engagement portion is connected to the main body of the respective one of housing or the butterfly disk by the mounting portion. The mounting portion is attached to the main body of the respective one of housing or the butterfly disk in a manner such that the mounting portion can articulate relative to the main body of the respective one of housing or the butterfly disk as the engagement portion resiliently deforms radially.

Abstract: A vacuum pressure control apparatus includes an annular elastic seal member formed with a valve seat, and a doubly eccentric butterfly valve element configured to come into contact or separate from the valve seat. The vacuum pressure control apparatus is to be placed on a pipe connecting a vacuum chamber and a vacuum pump. The vacuum pressure control apparatus is configured to rotate the butterfly valve element in a first direction from a first valve closed position corresponding to an initial state to change vacuum pressure in the vacuum chamber. The vacuum pressure control apparatus further includes a control unit configured to rotate the butterfly valve element in a direction opposite to a first direction so that the butterfly valve element is moved to a second valve closed position different from the first valve closed position.

Abstract: A valve assembly having a valve housing, the valve housing defining a passageway. A flapper valve arranged within the passageway is coupled to a rotatable valve shaft. A flexible wall, sealed along opposed edges to the valve housing, is controllable to at least two positions. The first position seals against the flapper valve and the second position releases the flapper valve allowing for ready movement of the valve.

Abstract: The disclosed embodiments include a ball valve seal having a main body and a seal finger extending from the main body, wherein the seal finger is configured to extend from the main body and contact and flex against an outer surface of a ball body of the ball valve seal when the ball valve is assembled.

Abstract: An operating valve includes a valve chamber which is formed in a main body having a passage, a valve body which is housed in the valve chamber and has a passage corresponding to the passage of the main body, a rotary shaft which is detachably connected to the valve body, an operating member which operates a rotation of the rotary shaft, and a bias member which biases the rotary shaft to a position of the valve body.

Abstract: A lightweight butterfly valve having a disk maintained in a fixed position on a compound shaft through an interlocking relation ship between each of the individual shafts of the compound shaft and the disk as the disk is moveable between an open or closed position with the butterfly valve may having other features such as an electric drive to quickly rotate the compound shaft to provide for rapid opening and closing the butterfly valve, a disk position indicator and a shaft stop to prevent the disk from being driven past a full open condition.

Abstract: Provided is an eccentric valve and a manufacturing method thereof. The eccentric valve has a tri-offset structure, and comprises: a valve body, a valve seat, a valve unit, a valve stem and a seal. The disc-shaped valve unit is disposed in a through hole centered in the valve body. The valve stem penetrates shaft holes on the valve unit and the valve body. Rotating the valve stem causes rotation of the valve unit for closing/opening the through hole. The valve seat is mounted on the inner surface of the through hole, and the seal is mounted on the outer surface of the valve unit. When the through hole is closed, the valve seat and the seal are mutually engaged. The inner surface of the valve seat is part of an oblique cone. The seal is a centrosymmetric ring, of which the outer surface is cambered.

Abstract: A leak detecting device for water filled vessel such as a swimming pool. An annular resilient seal having a central opening contacts the surface of the vessel under water and creates a seal between the resilient seal and the vessel. A rigid housing open in its interior is coupled to the resilient seal and has an opening for an inlet to deliver fluid into the interior of the housing, or couple a flow meter thereto to measure the fluid flow, or deliver a dye into the housing and through the central opening of the resilient seal.

Abstract: High temperature seals for use in rotary valves are described herein. An example seal for use with a rotary valve includes a primary seal to engage a flow control member when the primary seal is in a first condition and a secondary seal at least partially disposed within the primary seal. The primary seal is to prevent the secondary seal from engaging the flow control member when the primary seal is in the first condition and the secondary seal is to engage the flow control member when the primary seal is in a second condition.

Abstract: A safety fitting for blocking a line, includes a blocking body that is located in a widened section of a housing, can be guided linearly in the direction of flow of the line and is held in an open position. The blocking body can be moved under the influence of a pressure fluctuation in the line or moved actively into a sealing position. The housing has a cylindrical sealing section, in which the blocking body engages with a cylindrical section thereby forming a cylindrical annular gap.

Abstract: A body for an actuated valve, the actuated valve comprising flow regulating means for regulating the flow of a fluid between an input bore and an output bore of a barrel, and actuating means for controlling a position of the flow regulating means, the body comprising: a barrel having at least the input bore and the output bore; an actuating volume inside of which at least part of the actuating means can be placed, wherein the barrel and the actuating volume are integrally formed in a single piece.

Abstract: Disclosed is a butterfly valve capable of controlling a flow of a fluid according to a rotation of a disk. The butterfly valve includes a body provided with an inner space having two open ends; a disk unit having a disk rotatably installed at the inner space, and configured to selectively open and close the inner space according to a rotation of the disk; a first seat portion protruding from an outer circumferential surface of the disk; a second seat portion protruding from an inner circumferential surface of the body, and arranged to face the first seat portion; and a sealing unit mounted to the body, and formed to contact the first and second seat portions such that a gap between the outer circumferential surface of the disk and the inner circumferential surface of the body is sealed. Under this configuration, the butterfly valve may have an enhanced reliability under low and high temperatures and a high pressure.

Abstract: Butterfly valves comprise a valve seat comprising a generally S-shaped cross-section and a valve seat retainer configured with appropriately shaped cooperating surfaces. Fluid control systems comprising such a butterfly valve are also disclosed.

Abstract: A butterfly valve for handling materials where the temperature of the materials flowing through the butterfly valve can exceed the breakdown temperature of the sealing member with the butterfly valve inhibiting contact of hot transportable materials with the sealing member to isolate the hot transportable materials from the sealing member. Cooling conduits maintain at least portions of the valve that contacts the sealing member at a temperature below the breakdown temperature of the sealing member to prevent seal failure.

Abstract: A butterfly valve with an undulating sealing surface, which has an inflatable annular seal mounted in a housing. A disk is pivotally mounted in the housing and has an edge with an undulating sealing surface and a peripheral sealing edge. The undulating sealing surface of the disk and a sealing face of the annular seal have non-mating profiles when the valve is in an unsealed condition. Pressure in a chamber proximate the annular seal causes the face of the annular seal to expand and deform and the face forms a high-pressure seal between the sealing ridge and the annular seal. Also includes a method for stopping delivery, of a conduit transportable material through a butterfly valve.

Abstract: A butterfly valve with an undulating sealing surface, which has an inflatable annular seal mounted in a housing. A disk is pivotally mounted in the housing and has an edge with an undulating sealing surface and a peripheral sealing edge. The undulating sealing surface of the disk and a sealing face of the annular seal have non-mating profiles when the valve is in an unsealed condition. Pressure in a chamber proximate the annular seal causes the face of the annular seal to expand and deform and the face forms a high-pressure seal between the sealing ridge and the annular seal. Also includes a method for stopping delivery of a conduit transportable material through a butterfly valve.

Abstract: A butterfly valve for handling materials where the temperature of the materials flowing through the butterfly valve can exceed the breakdown temperature of the sealing member with the butterfly valve inhibiting contact of hot transportable materials with the sealing member to isolate the hot transportable materials from the sealing member. Cooling conduits maintain at least portions of the valve that contacts the sealing member at a temperature below the breakdown temperature of the sealing member to prevent seal failure.

Abstract: A pressure control butterfly valve includes a valve disc rotatable in a vertical direction relative to a flow passage in a body, a seat ring reciprocating in a direction of the flow passage to allow a valve seat seal part to abut on and separate from the valve disc, and a valve opening/closing mechanism provided with an airflow path to which air is supplied in a direction of separating the seat ring from the valve disc and with a spring for biasing the seat ring toward the valve disc. The valve opening/closing mechanism is for nonslidably rotating the valve disc from which the seat ring has been separated by supply of air to the airflow path and for allowing the seat ring to abut on and separate from the valve disc by means of the supply of air to the airflow path and the biasing force of the spring when the valve disc has been rotated to a valve-closed state, thereby controlling pressure in the flow passage.

Abstract: An exhaust device for adjusting an exhaust gas cross sectional area of an exhaust passage in a combustion engine includes a valve body arranged in the exhaust passage communicating to an exhaust port of the combustion engine; a valve shaft fixed or integrally formed to the valve body and arranged so as to transverse the exhaust passage, the valve shaft changing the opening of the valve body by turning with the valve body about an axis of the valve shaft; a pair of bearing members for supporting rotatably the valve shaft at both ends thereof in a axial direction of the valve shaft; and a stopper arranged on the valve shaft so as to face an end face on the inward side of the exhaust passage of each bearing member in the axial direction. The stopper is restricted in the axial direction by the end face of each of the bearing members so that the valve body and the valve shaft do not move in the axial direction.

Abstract: A butterfly valve for handling materials where the temperature of the materials flowing through the butterfly valve can exceed the breakdown temperature of the sealing member with the butterfly valve inhibiting contact of hot transportable materials with the sealing member to isolate the hot transportable materials from the sealing member. Cooling conduits maintain at least portions of the valve that contacts the sealing member at a temperature below the breakdown temperature of the sealing member to prevent seal failure.

Abstract: Apparatus for increasing stiffness in a seal are disclosed. A disclosed apparatus includes a first flexible member having a curved sealing surface and a second flexible member adjacent to a retainer side of the first flexible member. The second flexible member is configured to increase a stiffness of the first flexible member in one of a plurality of flow directions.

Abstract: The invention relates to a valve comprised of a housing with a valve seat for a flap that is rotatably mounted on a drive shaft. The exterior of the flap is provided with a first piston sealing ring and a second piston sealing ring that are placed inside an encircling groove of the flap. Each sealing ring is provided in the form of a metal ring. The first ring has a first gap and the second ring has a second gap that are not aligned with one another. The invention also relates to the use of said valve.

Abstract: A flap valve for fuel aggregates, such as fuel cells, comprises a flap arranged within a flow channel. A shaft for pivoting the flap is connected to the flap. Further, a seal disposed in a recess of the channel wall is provided, which comprises at least one pressure pocket connected with the flow channel.

Abstract: A shut-off device (1) includes a housing (2) and a butterfly valve (4). The butterfly valve (4) can be swivelled using a drive shaft (3). When the butterfly valve (4) is closed, the butterfly valve (4) is sealed off from the housing (2) and from the pipe connection by an annular seal (7). The annular seal (7) is held on a face (5) of the housing (2) by a backup ring (6). The annular seal (7) is attached to the backup ring (6) using two annular projections (11, 12). The two annular projections (11, 12), respectively, interface with annular grooves (13, 14) provided on the backup ring (6). A fluid pressure chamber (22) is formed between the backup ring (6) and the annular seal (7), and a fluid connection pipe (24) extends through the backup ring (6) into the fluid pressure chamber (22).

Abstract: A hand-operated hemispherical or spherical valve that provides an improved seal when dealing with fluids containing, or consisting entirely of, particulate matter is provided by the present invention. The valve utilizes an inflatable elastomeric valve seat that interacts with a primary closing member to permit or restrain the flow of fluids or particulate matter in a channel. The valve is opened and closed by turning a handwheel that is connected to a drive shaft. A sleeve having a cam is mounted on the drive shaft such that the cam engages a pressurized gas supply switch that inflates the inflatable elastomeric valve seat or seats when the hand wheel is turned to a closed position. Conversely, when the hand wheel is turned to an open position, a valve drive shaft, key and keyway function in conjunction with the drive shaft to turn the sleeve and disengage the cam such that the elastomeric valve seats are deflated prior to the primary closing member moving out of the closed position.

Abstract: A retaining piece of a ball valve is provided with an engaging surface and a groove defined to provide resilience to the engaging surface which engages with an outer surface of a ball. With such an arrangement, the engagement between the outer surface of the ball and the engaging surface is fluid-tight. Furthermore the engaging surface is resilient and is able to deform slightly to suit the surface of the ball even after a long-term use, and therefore prolongs the operation life of the ball valve.

Abstract: A sealing member 11 made of an elastic material secured to the outer peripheral edge of a door plate 10 is provided with support portions 11a and 11b that extend in a direction to intersect the door plate 10, and the support portions 11a and 11b are directly supported by the outer peripheral edge of the door plate 10. Sealing portions 11c and 11d pressed onto a sealing surface 12a of an air passage casing 12 are so formed as to be directed toward the central portion of the door from the support portions 11a and 11b, and the sealing member 11 is folded, in cross-section, from the outer peripheral edge of the door plate 10 toward the central portion of the door due to the support portions 11a and 11b and the sealing portions 11c and 11d.

Abstract: The valve includes a closure disc (34) sealable at its rim to a valve seat (18) so that in this position the seat (18) and rim define between them an annular space (54) which is connected to a port (60) by passages (54, 56, 58) extending through a mating face (e.g. carbon fibre gasket (22)) of the valve seat (18). As shown the space (54) is a recess in the disc rim defined between fibre seal rings (46, 48) but other arrangements are disclosed in which the seal rings and/or recess may be accommodated in the valve seat. The port (60) may be used for leakage detection, pressure monitoring of bleeding or fluid injection.

Abstract: A throttle body (11) has a through-bore (18), a circular throttle blade (20) of nominal uniform thickness is disposed within the through-bore and on a cylindrical shaft (22). The through-bore has two generally semi-circular ledges (56, 58) spaced upstream and downstream respectively from an imaginary flat plane that contains the shaft axis, each at a distance substantially equal to one-half the blade thickness. One ledge occupies essentially one semi-circumference of the through-bore for sealing with one of the opposite semi-circular perimeters of the throttle blade when the blade is closed, and the other occupies essentially an opposite semi-circumference of the through-bore for sealing with the other semi-circular perimeter of the blade when the blade is closed.

Abstract: A seat structure for a ball valve which includes a seat member formed by rolling up an alternate stack of a thin steel plate and a thin graphite plate. The seat member is provided with a fixture portion fixed into an inner periphery of the valve body and a ball contact which is in contact with a surface of a valve ball provided between the inflow vent side and the outflow vent side. The seat structure improves an anti-abrasion and enables a secure functioning of the ball valve at a high temperature and high pressure.

Abstract: A seating ring having a unique surface designed to engage with the convex outer surface of a valve disc, thereby providing a uniquely tight and bi-directional seal. The seating ring has a first, free end, an angled contact point adjacent to the free end, a convex sealing surface adjacent to the angled contact point, a hairpin curve adjacent to the convex sealing surface, and a second, mounting end.

Abstract: Rotatable valve assembly includes a mounting mechanism for rotatably mounting a valve in a housing. The mounting mechanism includes a shaft having an outside end extending through the housing. A conversion mechanism converts fluid pressure in the housing into torque exerted on the shaft. A release mechanism is located outside the housing for preventing rotation of the shaft and valve when the torque exerted on the shaft is below a selected magnitude. A linearizing mechanism converts the forces exerted on the release mechanism by the shaft into a linear force. The release mechanism allows the shaft to rotate when the torque exerted on the shaft and the linear force exerted on the release mechanism exceeds a selected magnitude. A seal is provided for sealing the gap between the valve and the housing in the closed position of the valve.

Abstract: A valve including a valve body having a centrally disposed aperture, a rotatable shaft, and a valve disc. The disc has a circumference with an outer edge and is disposed about the shaft such that the disc rotates to an open position and a closed position within the aperture. The valve body further includes a body moment arm about the circumference of the aperture, a body annular recess about the body moment arm and an annular seating ring retainer also about the circumference of the aperture. The seating ring retainer includes a retainer moment arm opposing the body moment arm and a retainer annular recess, a portion of which adjoins the body annular recess. An annular seating ring, also disposed about the circumference of the aperture, has a first end including a tip and a sealing surface adapted to contact the outer edge of the disc when the disc is in the closed position.

Abstract: A method for adjusting sealing engagement of a valve seat includes providing a valve with a disk in a flow passageway and a valve seal with a seat positioned for sealing engagement with the disk, the valve body and seal together defining a channel having a seal surface lubricated to resist adhesion of the surface and polymeric material, the valve body defining a passage for external access to the channel; injecting liquid polymeric material through the passage into the channel, the polymeric material in the channel pressuring the valve seat toward sealing engagement with the disk; allowing the polymeric material to harden; producing a tunnel through the hardened polymeric material from an external port to the lubricated surface of the seal; and injecting liquid polymeric material under pressure through the tunnel into the channel and causing the liquid polymeric material to flow along the lubricated surface of the seal to collect in selected regions to improve sealing engagement of the seat with the disk.

Abstract: A sealing arrangement for a valve or shaft is disclosed which is designed to respond to movements of a rotatable element in a particular manner and to increase sealing pressure with increasing fluid pressure. The seal undergoes a radial compressive type movement as the pressure within a vessel housing increases between opposed sealing sleeves and this causes an increase in the sealing pressure. This predetermined movement of the seal creates a spring bias in the seal, urging the seal to return to the original, less stressed condition. Preferably, the seal is of a composite structure and a particular component of the intermediate wall section creates this spring bias. This structure has improved operating characteristics and accommodates a wider range of resilient materials to be used for the sealing washer.

Abstract: The present invention comprises an improved two-way dynamic shaft-sealing member for a fluid transport system having a butterfly valve with an inflatable seal with the improved shaft-sealing member including a rigid race secured to and carried by the interface portion of the inflatable seal to maintain the integrity of the interface portion of the seal with a compressible sealing ring located in the race and held in confinement by the race to hold the sealing ring in a sealing condition against the inside of the race and the outside of the shaft to prevent fluids from escaping therepast as the shaft is moved or the inflatable seal is inflated or deflated.

Abstract: A stop cock for a liquid container, comprising a substantially annular valve housing, a circular valve rotatably mounted in the valve housing, a handle mounted on an operational shaft for rotating the valve between a closed and open position, a seat mounted in the valve housing and cooperating with the valve in the closed position, characterized in that the handle (21) comprises a recess (28) for rotatably receiving a stop bush (29) that comprises a cam (30) which in the closed position cooperates with an indentation (42) of a top plate (24) arranged on a boss (9) and includes a circular passage for shaft (7), said stop bush (29) having an unround passage (33) for mounting a correspondingly formed driving shaft (34) of an unlocking lever (35), the handle (21) and the top plate (24) in a plurality of positions.