Abstract: The switching device for switching high electrical currents and voltages has at least one switch pole (1, 1?, 1?) which is operated by means of a rotatable shaft (8, 8?, 8?). Furthermore, the switching device has at least one lever system (10, 10?, 10?), a first switching linkage (11) and at least one drive (2) with a drive rod (24), with the rotatable shaft (8, 8?, 8?) being connected to the lever system (10, 10?, 10?), the lever system (10, 10?, 10?) being connected to the first switching linkage (11), and the first switching linkage (11) being operatively connected to the drive rod (24). Movements of the drive rod (24) are converted to rotary movements of the rotatable shaft (8, 8?, 8?). The physical space which is required for installation of the switching device is intended to be capable of being matched to the physical circumstances.

Abstract: Disclosed is a vacuum switchgear wherein a ground switch, a load switch, and an external connecting conductor to be electrically connected with the inside and outside of the vacuum container are provided in a vacuum container; the ground switch and the external connecting conductor are electrically connected in the vacuum container; and the vacuum container has a joint construction of a body portion having openings on both ends thereof, and a lid joined to the opening of the body.

Abstract: A hybrid high-voltage or medium-voltage breaker device includes an enclosure filled with a dielectric gas, a vacuum switch, a gas switch and an operating rod. The vacuum switch includes a fixed first arc contact and a second arc contact which can move in translation in an axial direction of the enclosure. The gas switch includes a fixed or quasi-fixed third arc contact and a fourth arc contact which can move in translation. The operating rod is connected to the fourth contact. The device also includes a connection arrangement for electrically connecting the second and third contacts and a displacement arrangement connected to the connection arrangement and to the rod which separates the second and fourth contacts from the first and third contacts, respectively.

Abstract: A gas-insulated switchgear device which has a first bushing which accommodates a first terminal, a second bushing which accommodates a second terminal, a first enclosure which contains an interruption unit, and at least one first disconnection unit which has a first fixed contact electrically connected to the interruption unit and a second fixed contact at ground voltage, a first moving contact which is electrically connected to the first terminal and can be coupled to the first and second fixed contacts, the moving contact being fixed to a rotary operating element and rotating rigidly therewith, the fixed contacts that can be coupled to the moving contact lying on the rotation plane of the moving contact.

Abstract: A switchgear wherein a connecting portion to be connected to a transmission side branch bus container and a connecting portion to be connected to a receiving side branch bus container are provided on a circuit breaker container in an up and down relation so as to face the same direction. Any one of the transmission side branch bus container and the receiving side branch bus container is connected to the connecting portion positioned on the upper side, and the other is connected to the connecting portion positioned on the lower side, and a transmission side power cable terminal container or a receiving side power cable terminal container is arranged at a position deviated horizontally from the axis of the transmission side branch bus container or the receiving side branch bus container.

Abstract: A gas insulated switchgear capable of performing maintenance and inspection of a breaker without shutting down a bus line includes a first case containing a breaker and having a bushing for leading a load and a second case containing a plurality of disconnectors and having a plurality of bushings for leading a plurality of bus lines to be connected to the disconnectors. The first case and the second case are connected to each other through a gas partition spacer.

Abstract: In an integrated type gas-insulated switching apparatus, a plurality of switching devices are provided. Each of switching devices includes a contact and an insulated container in which the contact is contained. The contact comprises electrodes adapted to be contacted with each other and separated therefrom. The insulated container is filled with an insulating gas. A conductive container is provided, to which the plurality of switching devices are connected, respectively. An insulated structure supports the conductive container.

Abstract: A gas insulated switchgear capable of performing maintenance and inspection of a breaker without shutting down a bus line. A gas insulated switchgear comprises a first metallic case 9a containing a breaker and having a bushing for leading a load 6a; and a second metallic case 9b containing a plurality of disconnectors and having a plurality of bushings for leading a bus line 6b, 6c to be connected to the disconnectors, wherein the first metallic case 9a and the second metallic case 9b are connected to each other through a gas partition spacer 7a.

Abstract: The hybrid circuit breaker has at least two series-connected arcing chambers, which are operated by a commmon drive via a transmission (29) connected upstream from it. It is intended to be possible to assemble this transmission (29) easily in the interior of the hybrid circuit breaker. This is achieved in that the transmission (29) is formed from at least two transmission parts which can be plugged together, with a first transmission part being firmly connected to the at least one first arcing chamber and a second transmission part being firmly connected to the at least one second arcing chamber. The transmission (29) also has means which allow the movements of the at least two arcing chambers to be technically suitably matched to one another and to be optimized with respect to the time sequence and switching speed thereof.

Abstract: A control system for at least one vacuum interrupter gap in a high-voltage switching device includes at least one non-reactive control resistor disposed in parallel with the vacuum interrupter. The non-reactive control resistor merges concentrically onto the vacuum interrupter chamber and is mechanically and electrically coupled thereto.

Abstract: A gas-insulated switchgear device for high- and medium-voltage applications, comprising an enclosure which contains a disconnection unit which is electrically connected to a first electric terminal and is arranged in the enclosure in a substantially central position, and a first interruption unit and a second interruption unit which can be connected electrically to the disconnection unit and, respectively, to a second electric terminal and a third electric terminal, the first and second interruption units being arranged mutually opposite with respect to the disconnection unit.

Abstract: A gas insulated switchgear capable of performing maintenance and inspection of a breaker without shutting down a bus line includes a first case containing a breaker and having a bushing for leading a load and a second case containing a plurality of disconnectors and having a plurality of bushings for leading a plurality of bus lines to be connected to the disconnectors. The first case and the second case are connected to each other through a gas partition spacer.

Abstract: The present invention provides a switchgear, which can achieve miniaturization and simplification while securing high operation reliability, and excellent in assembly, operability and inspection, and further, has a compact size. A fluid pressure operating section is provided in a mechanical box arranged on a lower end portion of a support porcelain tube. Insulated operating rods are received in the support porcelain tube, and connecting mechanisms are received in a container. Switching contacts of circuit breaker and disconnecting switches and the fluid pressure operating section are connected via the connecting mechanisms and the insulated operating rods.

Abstract: An electromechanical relay including a mechanical displacement electrical contact and a transistor parallel-connected with the electrical contact. The contact is closed for a voltage V corresponding to the forward direction of the transistor and a powering-on of the transistor that starts before the closure of the contact and ends after the closure. The contact is opened for a voltage V corresponding to the forward direction of the transistor and a powering-on of the transistor that starts before the closure of the contact and ends after the closure. Such an electromechanical relay may find particular application to electromechanical switches, hybrid relays.

Abstract: Unit-forming bus bars including input terminal bus bars and output terminal bus bars are secured through an insulation layer to a rear surface of a heat radiation member that is exposed outside an electric connection box case, and switching devices are mounted on the bus bars. Relay switches that are different from the switching devices are mounted on a relay board. The relay board and a control circuit board for controlling driving of the switching devices are disposed on a surface facing away from the rear surface of the heat radiation member, and are parallel to each other.

Abstract: An air-insulated high-voltage disconnector including a pivotally-mounted arm suitable for pivoting at one of its ends about a horizontal axis that is perpendicular to the axis &Dgr; of the arm, and also suitable for turning about its own axis &Dgr;, the free end of the arm carrying a contact part or “hammer” which, when the disconnector is in the closed position, co-operates with a jaw comprising a jaw support to which two facing rows of contact fingers are fixed, wherein the hammer is equipped with contact tabs co-operating with the contact fingers, each contact tab forming a wedge of angle &bgr;, which wedge acts, during disconnector closure, to meet the corresponding row of fingers with an angle of attack &agr;, said angle of attack &agr; being less than 90°.

Abstract: A gas-insulated switch gear has a plurality of bay units having bus ducts each containing a three-phase bus and connected by bellows expansion joints. When the bay unit needs to be inspected for maintenance, the bellows expansion joints are compressed, and only the bay unit can be pulled out of the gas-insulated switchgear.

Abstract: A hybrid interrupter device includes a casing filled with a dielectric gas; a vacuum interrupter having a first arcing contact which is fixed and a second arcing contact which moves in translation in the axial direction of the casing; a force exertion device for exerting a force on the second contact while the vacuum interrupter is allowing current to pass; a gas interrupter having a third arcing contact which is fixed and a fourth arcing contact which moves in translation; and a drive rod connected to the fourth contact. The device further includes a connection device electrically interconnecting the second and third contacts, and capable of being moved in translation together with the second contact; and a displacement mechanism connected to the connection device and to the rod for displacing them so as to separate the second and fourth contacts from the first and third contacts, respectively.

Abstract: A mobile electrical transformer assembly is mounted on a trailer and includes a three phase transformer. The electrical switching for the transformer includes a circuit interrupter having three vertical towers at transversely spaced positions. Each tower and its associated lightning arrester is mounted on two arms of one of three vertical posts in a row. In respect of the outer posts, both of the arms are pivotal about the vertical axis of the post to move the tower and the arrester outwardly to increase the spacing. The arm of each tower includes a bracket at the bottom mounted for pivotal movement about a horizontal axis for movement of the tower from a vertical operating position to an inclined transport position. The arm of each arrester is movable so that the arresters are moved in the transport position to a location out of alignment with the respective tower.

Abstract: A gas-insulated switchgear device. A casing is provided with a first connection terminal and a second connection terminal, an interruption unit, and a disconnection unit. The disconnection unit includes a first fixed contact connected to the second connection terminal. A second fixed contact is at ground potential. A third fixed contact is connected to the first connection terminal. A first moving contact can be coupled to the third fixed contact. A second moving contact can be coupled to at least one of the first and second fixed contacts, and is electrically connected to the interruption unit. The second moving contact is rigidly fixed to a rotating actuation element. At least one of the first and second fixed contacts lies on the rotation plane of the second moving contact. The interruption unit includes an interruption chamber having a rotating case with a stationary contact and a mobile contact. A longitudinal axis of the interruption chamber is aligned with the rotating actuation element.

Abstract: A hybrid gas insulation switchgear apparatus comprises an enclosure in which an insulating gas is sealed, a bushing unit provided for the enclosure, a breaker unit disposed inside the enclosure, a disconnector unit disposed inside the enclosure and including disconnectors to be connected electrically in series to both sides of the breaker unit, an earth switch unit disposed inside the enclosure and including earth switches disposed between the breaker unit and the disconnectors, respectively, the earth switches being provided with main pole side electrodes disposed on the side of the breaker unit, and a current transformer unit mounted to the enclosure. The bushing unit including bushings each having a conductor connected to an electrode in the disconnector on a side opposite to the breaker.

Abstract: A module for a high- and medium-voltage electric station, comprising: a supporting frame, which has a fixed part and a movable part; first actuation means, which are suitable to move said movable part; first and second sets of three insulating posts, arranged on the fixed part along two corresponding rows; first and second disconnection contacts being respectively associated with the insulating posts of the first and second sets and being electrically connectable, in input and in output with respect to the module, to corresponding electric terminals.

Abstract: A gas-insulated switchgear having three gas-insulated hermetic vessels containing a disconnector for disconnecting a circuit and shunt conductors connected in parallel to each other between the disconnectors of the three hermetic vessels. The shunt conductors each include a conductor having terminal portions extending through and penetrating into the hermetic vessels and a main body portion connected and shunted between the terminal portions for parallel distributing an electric power from a first hermetic vessel to second and third hermetic vessels, an insulating material covering the main body portion and an electrically conductive coating disposed on an outer surface of the insulating material and grounded. The main body portion of the conductor is disposed outside of the hermetic vessels.

Abstract: A circuit interrupting device for use with an electrical power distribution system, comprising a circuit interrupter that includes a primary contact and a movable contact movable relative to the primary contact between a closed position allowing current to pass through the circuit interrupter and an open position separating the contacts and preventing the current from passing through the circuit interrupter. An actuator is coupled to the circuit interrupter. The actuator includes a shaft coupled to the movable contact of the circuit interrupter for substantially simultaneous movement without insulation being disposed between the shaft and the movable contact. The shaft moves the movable contact from the closed position to the open position upon occurrence of a fault current. An electronic control is electrically connected to the actuator and communicating with the actuator to trigger the shaft to move the movable contact of the circuit interrupter from the closed position to the open position.

Abstract: In order to realize reduction of a gas insulated switchgear, a connection bus for connecting potential current transformer units, a first connecting unit, power receiving units and transformer connecting units or for connecting the potential current transformer unit, a bypass unit, a first connecting unit, the power receiving units and transformer connecting units is arranged horizontally to a connecting unit and in parallel thereto. Thereby height dimensions of the transformer connecting units, potential current transformer units and transformer connecting units can be made small and thus a height dimension of the entire apparatus can be made small.

Abstract: This hybrid circuit breaker has at least two series-connected arcing chambers which are operated by a common drive or by separate drives and are filled with different arc extinguishing media. The arc extinguishing and insulating medium in the first arcing chamber surrounds the second arcing chamber in an insulating manner. The aim is to provide a hybrid circuit breaker which can be produced economically and which has high availability. This is achieved, inter alia, wherein means are provided which always ensure that the movement of the first arcing chamber leads the movement of the second arcing chamber during a disconnection process, and that the movement of the second arcing chamber always leads the movement of the first arcing chamber during a connection process.

Abstract: A gas insulated switchgear capable of performing maintenance and inspection of a breaker without shutting down a bus line. A gas insulated switchgear comprises a first metallic case 9a containing a breaker and having a bushing for leading a load 6a; and a second metallic case 9b containing a plurality of disconnectors and having a plurality of bushings for leading a bus line 6b, 6c to be connected to the disconnectors, wherein the first metallic case 9a and the second metallic case 9b are connected to each other through a gas partition spacer 7a.

Abstract: A gas insulation switchgear having a lowered overall height is provided.

Abstract: A gas insulation switchgear having a lowered overall height is provided.

Abstract: The present invention provides a switchgear, which can achieve miniaturization and simplification while securing high operation reliability, and excellent in assembly, operability and inspection, and further, has a compact size. A fluid pressure operating section is provided in a mechanical box arranged on a lower end portion of a support porcelain tube. Insulated operating rods are received in the support porcelain tube, and connecting mechanisms are received in a container. Switching contacts of circuit breaker and disconnecting switches and the fluid pressure operating section are connected via the connecting mechanisms and the insulated operating rods.

Abstract: In a high-voltage circuit breaker having an interrupter unit that can be actuated mechanically and that can be driven by a switch rod made of an insulating material, it is provided that the switch rod has at least two segments that are pushed into one another in partially overlapping telescoping fashion and that are connected with one another, the region in which the segments overlap one another and/or the segment having the larger outer diameter being arranged in the region of the greatest mechanical loading of the switch rod.

Abstract: In an integrated type gas-insulated switching apparatus, a plurality of switching devices are provided. Each of switching devices includes a contact and an insulated container in which the contact is contained. The contact comprises electrodes adapted to be contacted with each other and separated therefrom. The insulated container is filled with an insulating gas. A conductive container is provided, to which the plurality of switching devices are connected, respectively. An insulated structure supports the conductive container.

Abstract: The single-phase circuit-breaker comprises at least one interrupting chamber formed by an insulating tube filled with an insulation gas, and it comprises at least one current transformer whose secondary is disposed in air around the primary at one end of the tube. The primary is at the high voltage electrical potential of the phase and is constituted by an annular metal support. The secondary is subjected to a high voltage electrical potential that is practically equal to the potential of the primary. The current transformer is thus integrated in the circuit-breaker, and the measurement electronics associated with the secondary can be located in air close to the secondary.

Abstract: A fault interrupter is provided that includes a high-speed disconnect in series with an interrupter wherein the circuit opening is via the interrupter and the circuit making is via the disconnect. A stored energy disconnect operating mechanism operates the disconnect between ground, open and closed positions and also charges the interrupter mechanism during a slow opening of the disconnect without fully charging the disconnect operating mechanism. Thus, the required operating forces to open the disconnect and charge the interrupter mechanism are reduced. During a manual opening, the disconnect operating mechanism trips open the interrupter, then only partially charges to begin opening the disconnect before releasing the stored energy. Continued operation of the disconnect operating mechanism slowly drives the disconnect open while charging the interrupter mechanism and closing the interrupter.

Abstract: The switchgear comprises a circuit breaker connected between a generator and a transformer, together with a disconnector connected between the circuit breaker and the transformer, the disconnector having a fixed pole common to three positions: a first position and a second position respectively for connecting together or isolating the transformer and the circuit breaker when the circuit breaker is respectively closed or open; and a third position for grounding the fixed pole when the circuit breaker is open. The fixed pole of the disconnector is electrically connected to the transformer, thereby making it possible to interconnect or to isolate or to ground the tranformer while using only one disconnector included in the switchgear.

Abstract: A rotary contact circuit breaker employs a crank to couple a switching mechanism to the rotary contact pole structure. The use of a crank allows for the mechanism and pole structure the individually optimized without effecting the performance of the other. In particular the crank allows for a mechanism that is able to achieve maximum torque delivery to the pole structure.

Abstract: A surge arrester for high system voltages is provided. The arrester comprises an elongated column composed of a plurality of coaxially arranged valve units. The column is mechanically divided into an upper and a lower column part, and the two column parts are interconnected via a moment-limiting articulated member. The articulated member has an upper bearing plate with a concave sliding surface, which makes contact with a convex sliding surface of a lower bearing plate. The upper bearing plate is connected to the grounded stand of the arrester via tensionally prestressed, insulating links. The articulated member comprises a number of springs, adapted to the stiffness of the lower column part, to keep the two bearing plates correctly positioned relative to each other in the transversal direction.

Abstract: Electric circuit breaker with means for adjusting the contacts comprising, for each electric phase, moving levers having main contacts and arc-breaking contacts co-operating with main contacts and arc-breaking contacts provided on a terminal bar there being provision for the levers loaded by springs to be supported by a crank pivoting about a pin and for the crank to be operationally connected to a link-rod articularly joined to an operating shaft and for each end of the operating shaft to have translatable and position-adjustable supports.

Abstract: An integral stationary arcing contact and arc runner for electrical switching apparatus is formed by an electrically conductive member secured to the line conductor adjacent the stationary main contact thereby providing a joint free path for the arc to pass from the arcing contact to the arc runner. Preferably, the electrically conductive member is a sheet metal member having a base section secured to the line conductor, an arcing contact section adjacent the stationary main contact and extending generally perpendicular to the line conductor and a runner section extending at an obtuse angle to the arcing contact section toward the arc chute. A support member between the arcing contact section and the housing transmits reaction forces imposed by the moving conductor assembly on the sheet metal member into the housing.

Abstract: An electric switch for use in a five-pole isolating switch used as a phase inverter has a fixed contact and a mobile contact cooperating with the fixed contact to open or close an electrical line. The mobile contact is moved in a longitudinal direction by an articulated pair of levers. An isolating switch used as a phase inverter having five switches comprises a single three-position actuator for maneuvering the mobile contacts through a linkage.

Abstract: A high voltage hybrid circuit-breaker has an arc circuit with a gas circuit-breaker connected in a series with a vacuum bulb. The housing is subdivided into a first compartment enclosed by an insulator for housing the primary contacts of the primary circuit and of the gas circuitbreaker and a second adjacent compartment (14) containing the vacuum bulb, defined by a conductive metallic shell. The movable arcing contact of the gas circuit-breaker is actuated with the movable primary contact by a primary control rod connected to a common mechanism, wherein the displacement of the movable arcing contact of the vacuum bulb is derived from the translational movement of the primary rod through an intermediate transmission lever received in the second compartment.

Abstract: An apparatus for operating a combined interrupter disconnect switch is disclosed. The disconnect switch is operated by a slow speed linear motion of a mechanism pullrod. The interrupter, which is a component of the disconnect switch arm, is operated by a high speed linear motion of the same mechanism pullrod. In a preferred embodiment, the apparatus of the present invention comprises: an operating rod; a high speed operating mechanism connected to the operating rod; a sliding gear having an elongated gear face; a motor, rotatably connected to the sliding gear; a coupling gear drive having a longitudinally disposed threaded shaft and an external gear face, connected to the operating rod and meshed with said sliding gear; a threaded rod threaded into the threaded shaft of the coupling gear drive; and a drive rod connected to the threaded rod and to the mechanism pullrod. The high speed operating mechanism and motor respectively provide high speed and slow speed linear motion to the mechanism pullrod.

Abstract: A circuit breaker comprises a vacuum interrupter and an isolator in series combination, the vacuum interrupter providing fast interruption of current and the isolator providing a large gap when in the open condition for additional safety and protection against transients. The circuit breaker may be operated by a single actuator device and is adapted to provide sequential isolation first by the vacuum interrupter, followed by the isolator to a fully open circuit condition, and on closing is adapted to first close the isolator under a no-load condition followed by closure of the vacuum interrupter to resume current flow. The isolator additionally provides for the single actuator device to slowly close the isolator with low force and to quickly close the vacuum interrupter with high force. An actuator mechanism also provides further control of the relative speeds of closure of the isolator and vacuum interrupter.

Abstract: This present invention concerns a circuit-breaker of the self-blasting type including a system for immobilizing the semi-mobile piston during a first part of displacement of the mobile contact assembly between the closed position and the open position and for displacing the piston axially during a second portion of the same displacement of the mobile contact assembly. This system includes at least one first longitudinal slot and at least one second longitudinal slot on the fixed tube, a freely rotatable locking tube carried by the fixed tube, aligned with the slots thereof and including at least one first longitudinal slot and at least one second longitudinal slot, at least one pin carried by the second tube and penetrating the first slot of the fixed tube and the first slot of the locking tube, and at least one pin carried by the piston and penetrating the second slot of the fixed tube and the second slot of the locking tube.

Abstract: A distribution circuit breaker for two circuits operated by a common handle, in which an arc gas generated in one circuit is prevented from flowing into the other circuit includes a breaking mechanism chamber (A) for a first circuit and another breaking mechanism chamber (B) for a second circuit are defined in a single circuit breaker case on each side of a partition (3a). Contact driving means (8) is forked at the lower end portion to have two fingers which are positioned on each side of the partition and to be spaced from each other, and movable contacts (10a,10b) are attached to the lower end portions of the fingers, respectively. An arc gas suppressing barrier is provided with respect to at least one movable contact.

Abstract: The present invention relates to a high-voltage circuit-breaker including a casing that is filled with a dielectric gas and that contains a first arcing contact and a second arcing contact, which arcing contacts are mounted to move in opposite directions from an open position to a closed position and vice versa, the first contact being secured by means of a ring to a tube mounted to slide in a support portion electrically connected to a terminal. Said ring is made of an insulating material, the first contact is extended by a rod that is in alignment with the contact, which rod is disposed on the side of the first contact that is further from the second contact, and is connected to a resistance, and said rod carries a switching member organized to connect said rod directly to said support portion during closure.

Abstract: A high voltage open-air switch has a movable disconnect switch blade which contains a circuit interrupter therein having interrupter contacts in series with the open air disconnect switch contacts. The circuit interrupter has a lower BIL rating than the switch. An operating mechanism causes the independent operation of the interrupter and disconnect switch such that there is a high speed opening of the interrupter contacts, followed by the low speed opening of the disconnect switch contacts, and a slow speed closing of the disconnect switch contacts followed by the high speed closing of the interrupter contacts. The switch can be adapted to numerous switch configurations and permits substantial savings in space by the reduced mounting space requirements for the interrupter assembly.

Abstract: A circuit-breaker having two interrupting chambers per pole, the chambers being disposed in a T or V configuration at the end of a column provided at its base with a control system for operating a drive rod, each chamber containing a moving assembly connected via a linkage to the drive rod, and main contacts and arcing contacts, wherein each chamber contains a semi-moving assembly including main contacts and arcing contacts co-operating respectively with the main contacts and the arcing contacts of the moving assembly, the semi-moving assembly in each of the chambers including a mechanism for moving it at a velocity of equal magnitude and of opposite direction to the velocity of the moving assembly with which it co-operates.

Abstract: Each interrupter unit (10, 12, 14) of the switch for medium voltage and high voltage has a drive shaft (30), a moving switch contact piece (18) and a transmission linkage (38) which connects the switch contact piece (18) to the drive shaft (30). All the interrupter units (10, 12, 14) are of identical construction. A drive lever (40) is seated in a rotationally fixed manner on each drive shaft (30), which drive levers (40) are connected to one another via connecting rods (44, 46). In order to bring about staggered switching, the drive levers (40) of at least two interrupter units (10, 12, 14) are arranged in a different rotation position with respect to their drive shafts (30).

Abstract: A gas-insulating switching unit includes a gas-filled housing containing a multi-pole vacuum switch and a three-position circuit breaker arranged below it. The vacuum switch is arranged so that the longitudinal axes of the horizontally positioned vacuum switching tubes are perpendicular to the front wall of the housing. The switch shaft of the circuit breaker is parallel to the front wall of the housing. Actuating rods are sealed against the front wall be bellows and can be used to operate the vacuum switching tubes. The circuit breaker is operated by a drive device via two pivoting levers that can be coupled by means of a fork opening.