Abstract: The described embodiments relate generally to devices, methods and systems for managing access to a memory card, such as a smart card, by a plurality of accessing devices. Certain embodiments relate to a smart card reader (SCR) for managing concurrent access to a smart card by a plurality of accessing devices, the SCR comprising: a processor; a channel manager responsive to the processor for interfacing with the smart card; a communication interface responsive to the channel manager for communicating with the plurality of accessing devices; and wherein, when a session is open on a first channel between a first accessing device and the smart card and the channel manager is configured to issue an open channel command to the smart card to cause the smart card to open a second channel between the smart card and the second accessing device in response to the session request.

Abstract: A sprinkler comprising a housing fitted with an inlet port connectable to a water supply line and extending into an inlet chamber, a hollow stem member with an inlet end thereof being in flow communication with said inlet chamber and an outlet end thereof being in flow communication with an irrigation head, a diaphragm seal sealingly fixed at peripheral boundaries thereof to the housing and sealingly articulated to the stem member and supporting it at an essentially upright position. The diaphragm is deformable between a first position in which the irrigation head is retracted within the housing and a second position in which the irrigation head projects from the housing.

Abstract: An energy efficient water sprinkler has a housing with primary and secondary water chambers each with a turning wheel for translating the force of impacting water to rotational motion of a central shaft journal. Water is forced through a central channel in the rotating shaft and discharged from the housing. A portion of the discharged water is directed to deflection fins on the outer surface of the housing to further impart rotational or energy to the rotating shaft.

Abstract: A rotating spray nozzle, comprising an elongate stem securable to a liquid-supply pipe, the stem defining a passageway therethrough for communicating a liquid from the supply pipe, the passageway communicating at least one inlet opening and at least one outlet opening defined in the stem; and a polymer nozzle body freely rotatably mounted on the stem for rotation about a nozzle axis, the nozzle body having an internal cavity in communication with the at least one outlet opening of the stem, and at least one nozzle defined through the nozzle body and communicating with the internal cavity, the at least one nozzle being offset from the nozzle axis to impart a driving couple to the nozzle body to cause rotation thereof when a liquid from the supply pipe is communicated through the at least one nozzle. The stem defines a longitudinal portion bounded at opposite ends thereof by integral annular shoulders having diameters greater than the longitudinal portion.

Abstract: The invention relates to a spray nozzle, particularly a high pressure nozzle, for descaling steel products, having a mouthpiece, which is provided with a discharge opening and a discharge chamber, which tapers towards the discharge opening. According to the invention the discharge opening spans a curved surface and a surface surrounding the discharge opening boundary at each point of said boundary strikes the discharge opening boundary at an angle between 65 and 95°, particularly 90° to the median longitudinal axis. Use e.g. for descaling nozzles.

Abstract: The invention relates to a method for the comminuting of natural or synthetic mineral products having a size of 10 nm to 30 mm, which are obtained from the upstream process in pre-comminuted form for example in a roller mill for inter-particle comminution, wherein these solids are further comminuted in a working process initially dry then wetted with liquid and in this liquid are comminuted so as to obtain a suspension that can be pumped, which suspension is subsequently ground to the desired final fineness by means of agitating mills.

Abstract: In a method for detaching a charge (5) which is stuck to the inner wall of a grinding pipe (1), the grinding pipe (1) is rotated in a targeted manner such that the charge (5) that is stuck is removed from the inner wall of the grinding pipe (1) as a result of multiple modification of the rotational speed of the grinding pipe (1) and, optionally, as a result of abrupt braking of the grinding pipe (1). Generally speaking, the material-dependent maximum angle of rotation F of the grinding pipe is not exceeded in order to avoid the charge that is stuck from falling in an uncontrolled manner. The invention supercedes labor-intensive and protracted methods for detaching such charges (5) since the tasks can be carried out by the same motor of the drive device (2) which is used to drive the grinding pipe (1) during the grinding process.

Abstract: Active protection system for a paper shredder, which includes an upper cover and a shedder plate on the upper cover. The paper shredder plate includes a touch structure, which engagingly interacts with a preferential power supply switch. When closed, the shredder plate prevents contact with the shredding blade. When opened, the shredder plate both initiates shredder normal operation, and prevents feeding of unexpected items into the shredder making accidental contact with the shredding blade. When an unexpected item contacts the safety structure, beneath the paper shredder plate, the protection system switches off the shredder power supply.

Abstract: An apparatus for making a cementitious composition may comprise a grinding mill for producing a cementitious composition from clinker and gypsum and classifiers for separating the cementitious composition into various portions. A primary portion of the cementitious composition has a particle size distribution such that substantially all of its particles are of a size of about 10 microns or smaller. A secondary portion and a remainder portion of the cementitious composition are combinable to form a resultant cementitious composition selected from Type I portland cement and Type III portland cement.

Abstract: A built-in module for an inverter and having tension control with integrated tension and velocity closed loops, where required tension feedbacks can be obtained by internal calculations of the inverter or feedback signals of a tension sensor. The tension control module is applied to provide a tension control for a winding mechanism which is operated by driving at least one motor. The tension control module firstly builds a tension control to provide a balanced tension to the winding mechanism. Afterward, the tension control module builds a velocity control to provide an accelerated or decelerated adjustment for the winding mechanism. Accordingly, the winding mechanism can stably maintain a tension-balanced operation.

Abstract: A towel dispenser includes a housing for receiving toweling. The housing includes a main body; a loading door that is configured to rotate relative to the main body between a closed position and an open position; and a guide system that includes a first roller attached to the main body and a second roller attached to the loading door. The towel dispenser may include a motor for driving dispensing of the toweling from the housing and an associated sensor. The towel dispenser can be mounted to an underside of a cabinet. In an aspect, the loading door includes a curved body and a lip that generally extends away from the curved body. A portion of the main body that extends over the lip when the loading door is in the closed position includes the motor therein.

Abstract: A towel dispenser includes a housing for receiving toweling. The housing includes a main body; a loading door that is configured to rotate relative to the main body between a closed position and an open position; and a guide system that includes a first roller attached to the main body and a second roller attached to the loading door. The towel dispenser may include a motor for driving dispensing of the toweling from the housing and an associated sensor. The towel dispenser can be mounted to an underside of a cabinet. In an aspect, the loading door includes a curved body and a lip that generally extends in parallel to a top surface of the housing away from the curved body.

Abstract: A towel dispenser includes a housing for receiving toweling. The housing includes a main body; a loading door that is configured to rotate relative to the main body between a closed position and an open position; and a guide system that includes a first roller attached to the main body and a second roller attached to the loading door. The towel dispenser can be mounted to an underside of a cabinet. In an aspect, the towel dispenser includes a motor and a transmission for feeding the toweling outside of the housing during dispensing of a towel, and an associated sensor. The motor is mechanically connected to the first roller by a transmission, and the second roller is connectable to the motor via the transmission.

Abstract: A towel dispenser includes a housing for receiving toweling. The housing includes a main body; a loading door that is configured to rotate relative to the main body between a closed position and an open position; and a guide system that includes a first roller attached to the main body and a second roller attached to the loading door. The towel dispenser may include a motor for driving dispensing of the toweling from the housing and an associated sensor. The towel dispenser can be mounted to an underside of a cabinet. In an aspect, the second roller includes an axis of rotation that is fixed relative to the loading door, and the first roller includes an axis of rotation that is substantially parallel with the axis of rotation of the second roller regardless of whether the loading door is in the closed position or the open position, or transitioning therebetween.

Abstract: A system for modifying a shock wave formed in a fluid by a body to modify effects of the shock wave on information transferred to or from the body. The system includes laser pulses for heating fluid along a path to form a volume of heated fluid expanding outwardly from the path, the path extending from the body and through the shock wave; an element for transferring the information to or from the body; and a timer for timing the transferring of the information relative to the heating of the fluid along the path to modify certain effects of the shock wave on the information.

Abstract: A device for controlling an aircraft during non-flying operations has a retractable tiller that extends with the nose landing gear of the aircraft. Ground crew use the control device to maneuver the aircraft for various ground-based operations. The tiller provides left and right directional input to the steering of the nose wheel. The tiller also provides throttle and brake controls, such as a twist-grip handle on the tiller. The throttle and brake controls are spring-loaded to an engine idle and braked position. Separate brakes also may be provided for additional braking control. The control device also includes various auxiliary controls for additional operations such as wing fold, tail hook extension and retraction, launch bar extension and retraction, etc. Other functions including engine start, engine shutdown, a vehicle system built in test and other functions and tests also may be provided on the control device.

Abstract: A samara wing including a main wing with a leading edge and a trailing edge. An aileron has a leading edge and a trailing edge and is pivotally attached proximate the trailing edge of the main wing and separated therefrom by a gap. The aileron is rotatable between the first position where the trailing edge of the aileron is facing forward in a plummet mode of operation and a second position where the trailing edge of the aileron is facing rearward typically for an autorotation mode of operation.

Abstract: Flotation systems including separately packed floats and life rafts are disclosed. Such systems, advantageously used for helicopters or other vessels, attach rafts to exterior covers of the floats. Thus, if not needed, or if maintenance or repair is required, the rafts may be removed from the float covers quickly and easily and without unpacking the floats themselves. Likewise, removal of the rafts permits maintenance to be performed on the floats without any need to unpack the rafts. Also identified are mechanisms for indirectly connecting both floats and rafts to vessels and for independently inflating both floats and rafts using a single actuator.

Abstract: A ground sensing system for an aircraft attaches to the aircraft's landing gear to provide a ground touch indication. The ground sensing system includes a bracket, an upper arm, a lower arm, a roller and a sensor. The bracket is mounted to the landing gear while the upper arm is pivotally and biasly coupled to the bracket. The lower arm is pivotally and biasly coupled to the upper arm. The roller mounts to the lower arm and extends just slightly beneath a lowermost surface of the tire when the aircraft is airborne. The sensor is triggered once a portion of the upper arm has sufficiently entered the sensor's field of view, which occurs when the roller is urged upward by the ground during landing.

Abstract: Structural panels for use in manufacturing fuselage bodies and other aircraft structures are disclosed herein. In one embodiment, a monolithic integrated structural panel is configured to include a skin, an array of stiffeners and an array of frames which are preferably arranged in a mutually orthogonal layout, without the need of cut-outs in any of the crossing elements. One advantage of the disclosed embodiments is that the frame and stringer members have continuous flanges and spliced webs. The disclosed embodiments herein are compatible with composite materials technology, offering another advantage, namely the possibility of manufacturing integrated products in a single cure (“one-shot”) cycle. A structure of composite materials, e.g. carbon fiber reinforced plastics, typically comprises a skin panel, reinforced by frame and stringer members.

Abstract: An inlet door and actuation mechanism for an auxiliary power unit has an actuation mechanism mounted within a housing. The housing includes a bearing mount for allowing a bearing on the mechanism to adjust angularly as the inlet door pivots. The bearing mount and bearing provides a fireproof enclosure between areas on opposed sides of a wall of the housing.

Abstract: An enhanced aerial delivery system addresses issues raised when large quantities of fluids, powders, and other agent materials are to be transported in and aerially dispersed by aircraft. Some aspects include positioning and securing of tanks aboard the aircraft to facilitate management and safety of the tanks and aircraft. Other aspects address coupling of the tanks and associated piping to lessen structural effects upon the aircraft. Further aspects deal with channeling, containing, and dumping stray agent materials that have escaped from the agent tanks on board the aircraft.

Abstract: A clip assembly (111) having a clamp member (115) with opposing fingers (121 and 123) configured to form a channel, and an insert member (129) that holds the fire detector wire (128) is disclosed. The insert member (128) is made of, coated with, or treated with an anti-friction material. The insert member includes end flanges (133, 135) that retain the insert member between the opposing fingers. The fire detector wire is installed into the insert member, and the insert member is then snapped into the channel formed by the opposing fingers of the clamp member.

Abstract: A peripheral device support assembly. The peripheral device support assembly includes two detachable armrest and support tray adapted to be attached to each arm of an office chair. The detachable armrest and support tray includes a mount for securing the armrest support unit to a chair arm and a first portion hingedly attached to the mount for allowing the first portion to swivel in relation to the mount. The detachable armrest and support tray also includes a second portion pivotally connected to the second portion such that the first portion folds back over a second portion for storage. A tray spans the distance between the second portion of each detachable armrest and support tray to provide additional workspace.

Abstract: The invention provides a support apparatus capable of supporting a monitor. The support apparatus includes a mounting base, a first frame mounted on the mounting base, a lock member, and a second frame. The first frame thereon defines a first direction and a second direction perpendicular to the first direction. The first frame includes a through hole along the second direction, a slide extending along the first direction, and a slot. The lock member includes a columnar member and a release part. The release part is disposed to pass through the through hole, and an end of the columnar member is disposed limitedly and movably in the slot. The second frame is disposed movably on the slide, and includes a hook. When the hook engages to the columnar member, the release part can be driven to disengage the columnar member from the hook.

Abstract: An apparatus for setting the spacing of a free standing range relative to a floor includes a base component for contacting the floor, a threaded element, and a winding follower. The winding follower extends into the helical recess of the threaded element such that the winding follower travels progressively further along the helical recess of the threaded element. A blocking member engages the winding follower during travel of the winding follower along the helical recess of the threaded element to resist a disengagement movement.

Abstract: A mounting platform for a lighting fixture comprising a substantially flat plate and an integral cutting guide. The integral cutting guide includes an aperture formed through the substantially flat plate and a flange formed around a perimeter of the aperture. The flange and the substantially flat plate intersect in a curve. The flange can form an angle of less than 90 degrees with respect to the bottom surface. The mounting platform can also include elongated slots for securing the mounting platform to a ceiling support member. The elongated slots are of a sufficient length to allow the mounting platform to be secured to the ceiling support member to allow placement of the integral cutting guide between a first ceiling support member and a second ceiling support member. The span between the first and second ceiling support members can be in the range of approximately 16 to 24 inches.

Abstract: A suction cup device includes a cup forming unit cooperating with a flat surface to create a volume-variable space, a liftable rod secured to a central portion of the cup forming unit, a bracing shell member having a force-transmitting surrounding wall in engagement with a peripheral portion of the cup forming unit, and a twistable cap member having a surrounding bottom wall in abutting against a circumferential abutment region of the bracing shell member and threadedly engaged with the liftable rod such that a manually twisted movement of the twistable cap member can result in axial movement of the rod so as to pull the central portion away from the flat surface to produce a reduced pressure in the volume-variable space and a biasing force to thereby ensuring fluid-tight engagement of the cup forming unit with the flat surface.

Abstract: A bracket for mounting a portable aspirator to a wall. The bracket allows easy securing and removing of the aspirator with one hand in emergency situations. The bracket will also secure the aspirator against a 10 G loading force. Electrical leads on both the aspirator and the bracket allow the aspirator to charge when secured.

Abstract: Adjustable mounting apparatus for securing electrical connectors and equipment to powersports vehicles such as motorcycles, all terrain vehicles and snowmobiles. These mounting brackets are low cost, compact and lightweight. The brackets install easily without the use of fasteners and are adjustable without the use of tools or modification allowing them to conform to surfaces that may be flat, curved or fully round.

Abstract: A universal metal stud clip is a support mechanism for securing one or more electrical boxes or other construction components to metal construction elements such as metal studs. The opposed spring arm design permits the clip to be oriented in any useful way and frictionally secured to metal studs of varying dimensions. Metal stud clips include one or more pair of resilient arms to frictionally engage metal studs. Using two or more pair of resilient arms provides a very stable attachment to the metal stud.

Abstract: A foldable urine collection device which comprises a pair of wire members having first and second opposed ends and having an upwardly disposed urine collection cup intermediate said first and second ends so that the urine collection cup is generally centrally disposed within a toilet bowl for use by a user wherein the first and second ends of the wire frame connect to opposing rims of the toilet bowl so as to secure the device therein. Also shown is an intermediately disposed net having a plurality of flexible fingers disposed so as to capture the collection cup therein in a manner so that a plurality of sizes of collection cups can be captured with the flexible fingers. The flexible fingers secure the cup within the urine collection device.

Abstract: An elevating mechanism includes a sleeve having a first end and a second end, and an elevating component installed inside the sleeve and having a third end and a fourth end. When the elevating component is located in a first position relative to the sleeve, a main spring is compressed by the elevating component at a first deformation. When the component is located in a second position relative to the sleeve, the main spring is compressed by the elevating component at a second deformation. The first deformation is greater than the second deformation. When the elevating component is located in the first position relative to the sleeve, a complementary spring is compressed at a third deformation. When the component is located in the second position relative to the sleeve, the complementary spring is compressed at a fourth deformation. The third deformation is greater than the fourth deformation.

Abstract: A mechanism for locking rails of a motor vehicle seat including a first rail joined to a structure element along a longitudinal axis of the vehicle, a second rail sliding in the first rail and supporting the seat frame of the seat, a first cross-bar pivoting in the second rail along an axis essentially perpendicular to the two rails coaxially held in a desired position relative to one another via a return mechanism of the first cross-bar, and a second cross-bar, which includes a first protuberance oriented toward the front of the seat and a second protuberance oriented toward the rear of the seat, connected to the first cross-bar so that the longitudinal displacement of the seat is controlled by the two protuberances.

Abstract: A portable device accessory is used to hold, grip or manipulate a portable device such as and not limited to mobile phones, MP3 players, portable entertainment/computing devices, and/or gaming devices. The accessory possesses two suctions cups connected by a neck and having an aperture for receiving a jack on earphone. Certain embodiments of the accessory will have tabs, ridges, groove and/or a space to receive earphones. The accessory permits a jack of earphones to be threaded through an aperture and the cord of the earphones to be wrapped around the accessory. The suction cups may be inverted to conceal the cord wrapped around a neck of the accessory and tabs may be used to hold inverted suction cups together.

Abstract: The concrete form tool apparatus allows a single worker to correctly position inner and outer stem wall forms. The apparatus saves time and labor by allowing a worker to quickly position forms. The apparatus properly positions inner and outer stem wall forms in a parallel relationship, a proper height relationship, and in a proper distance relationship.

Abstract: A valve assembly has a valve body having an inlet section for a pressurized fluid and an outlet. A piston is movable within the valve body between an open position and a closed position blocking fluid communication. The piston has an end section, a sealing section and a middle section located between the end section and the sealing section. A cavity receives the piston within the valve body. The cavity has a superior chamber, an intermediate chamber, and an inferior chamber. A spring within the superior chamber exerts a spring force onto the piston to urge the piston towards the open position. An actuator device provides upon actuation for a first flow of fluid outside the cavity from the inlet section to the superior chamber. The first flow causes a pressure within the superior chamber to increase until it is about the same as the pressure within the container so that the spring force moves the piston to the open position.

Abstract: A valve is described having an inlet, an outlet, a sealing element and a device to generate a magnetic field, whereby the sealing element can be moved at least partially by the device and whereby the sealing element connects the inlet to the outlet in a fluid-conducting manner in that the sealing element lifts off at least partially from a valve seat wherein the sealing element is made at least partially of a foam element that can be deformed by the magnetic field.

Abstract: A cable drawworks for a drilling rig is provided having a three-phase AC electric motor controlled by a variable frequency drive control system. A primary drive transmission consisting of a chain and sprockets connects the motor to a drum shaft that passes through the hub of a cable drum such that the cable drum is rotatably mounted on the drum shaft. The drum shaft connects to a secondary drive transmission, attached to the frame via an oscillating plate assembly, that connects the drum shaft to the cable drum. Each end of the cable drum has a brake drum and a brake band wrapped around thereon. A brake actuating system is used to tighten the bands around each drum during braking conditions and includes an equalization linkage system between the brake bands resulting in equal braking forces being applied to each brake drum.

Abstract: A come-along for pulling loads includes a rope winding mechanism that enables the rope to be wound and fed out smoothly. The rope winding mechanism includes a positioning hole that reduces the angle between the secured end of the rope and an axial tube about which the rope is wound. The come-along also includes a rope securing mechanism. The secured end of the rope has a seal head that fits through an installation hole and rests against the positioning hole. A helical slot around the axial tube enables the rope to wind evenly.

Abstract: A shock-absorbing fence comprises: a guard net provided in a stretched state between main posts provided to stand at a predetermined interval; a safety net attached between a skirt of the guard net and a ground; and a member joining an upper rim of the safety net to the skirt of the guard net as well as securing a lower rim of the safety net to the ground, the member including a horizontal support rope member provided along the lower rim of the safety net and a plurality of hillside support rope members connecting between a plurality of points of the horizontal support rope member and a plurality of hillside anchors, the safety net being allowed to deform in an extended manner following deflection and deformation of the guard net, while maintaining a gap below the guard net in a closed state, in case of rockfall.

Abstract: A device for gassing a liquid, particularly for membrane facilities used in immersion operation, has a gas supply channel and at least one gas lance from which a gas flow exits in gassing operation. The gas lance is connected to the gas supply channel via at least one connection channel including a first mouth area on the side of the gas lance and a second mouth area on the side of the gas supply channel and generating as a throttle a flow pressure loss of the gas flow entering the gas lance. Below the first mouth area an extension section is provided, which adjoins the gas lance and has an opening below the first mouth area.

Abstract: Apparatus for aerating waste water, provided with a container for waste water and a rotor which is rotatable about a substantially vertical axis (1) and the downward directed part of which can reach into the waste water, which rotor comprises blades (4) having surfaces which are orientated substantially radially and axially, wherein a surface (12) curved in the direction of rotation of the rotor is present close to the upper edge (8) of a blade (4), and wherein the curved surface close to the upper edge forms an angle of between 10° and 60° with the vertical plan of the blade.

Abstract: An apparatus for the transfer of mass and heat including a membrane having a hydrophilic surface and an opposing hydrophobic surface. The construction prevents transmission or leakage of fluids from one side of the membrane to the other regardless of pressure gradients within the membrane bubble point or water intrusion pressure range, but allows the transfer of vaporized fluid from one side of the membrane to the other.

Abstract: A twist locking connector for a steam humidifier. The steam humidifier includes a tank for heating water to generate steam and a steam tube receiver structure in fluid communication with the tank. The steam tube receiver structure has an opening configured to receive a steam tube, where the opening has a plurality of ramp structures about the opening on a side facing the tank. The steam humidifier also includes a steam tube for transmitting steam from the tank to a duct, the steam tube having a plurality of locking tabs adjacent to an end and a flange adjacent to, but separated by a distance from, the locking tabs. The steam tube is assembled to the steam tube receiver by inserting the steam tube through the opening in the steam tube receiver structure and rotating the steam tube to cause the locking tabs to engage with the ramp structures.

Abstract: An insulator for a bushing may include a plurality of insulator bodies, a center hole formed to each insulator body for coupling the insulator bodies of the bushing to a bushing bracket, and operation slot being formed on each insulator body, wherein the insulator bodies are separately and relatively-rotatably coupled each other.

Abstract: Disclosed is a clamping device for securing and clamping work-piece quickly and efficiently. The clamping device includes an elongated slide bar; a first support assembly and a second support assembly. The first support assembly affixed at a proximal end portion of the elongated slide bar includes a first body portion, and a first clamping member. The second support assembly includes a second body portion, a second clamping member configured on the second body portion, and a locking mechanism configured on the second body portion. The second body portion is slidably coupled to the elongated slide bar for assuming a plurality of positions with respect to the first body portion. The first clamping member and the second clamping member are positioned in a spaced apart relationship for abuttingly clamping the work-piece there between to assume a clamped position of the plurality of positions.

Abstract: A universal holding fixture assembly includes a plurality of linear actuators supported by the fixture and adapted to engage and support a workpiece relative to the fixture. A linear displacement member is supported by a housing and adapted to move between retracted and extended positions. An end effector assembly is operatively supported by the linear actuator and adapted to engage the workpiece when the linear displacement member is in its extended position. A sensor is operatively supported by the end effector assembly and is responsive to contact with the workpiece to establish a datum of the position of the linear actuator relative to the workpiece.

Abstract: A automatic truss jig setting system is disclosed that includes a table including a plurality of segments with a side edge of adjacent segments defining a slot. At least one pin assembly, and optionally a pair of pin assemblies, is movable independently of each other along the slot. Movement apparatus is provided for independently moving the pin assemblies along the slot. Each of the side edges of the segments associated with the slot defines a substantially vertical plane with a zone being defined between the substantially vertical planes of the side edges, and the movement apparatus is located substantially outside of the zone of the slot. The invention may optionally include a system for handling the obstruction of pin assembly movement, and a system for keeping track of the position of the pin assembly when the pin assembly has encountered an obstruction.

Abstract: A holding device for a rim of a vehicle wheel having a base plate which has a central recess for being pushed onto the shaft of a balancing machine, having a plurality of rotatably mounted holding elements and having at least one coupling element which is arranged coaxially with respect to the central recess and is mounted rotatably on the base plate, the holding elements and the coupling element having an interacting coupling for the positive coupling of the rotational movement of the holding elements. There is provision, in addition to the coupling which bring about the positive connection, for the holding elements and the coupling element to have a further coupling mechanism for the frictional coupling of the rotational movement of the holding elements, and for at least one fixing device to be provided for fixing the holding elements, if required.