Abstract: A variable vane actuation assembly for gas turbine engines having rotatable stator vanes comprises an engine casing, a unison ring, a bumper ring, a radial spline connection and a plurality of bumper shims. The engine casing is configured to encase the rotatable stator vanes. The unison ring is disposed concentrically with the engine casing. The bumper ring is disposed concentrically between the engine casing and the unison ring. The radial spline connection extends from the engine casing and joins with the bumper ring to permit the bumper ring to float radially with respect to the engine casing, but prevent the bumper ring from rotating circumferentially with respect to the engine-casing. The plurality of bumper shims are positioned between the unison ring and the bumper ring to limit deformation of the unison ring.

Abstract: A turbocharger comprising a turbine housing where at least one supply channel supplies an exhaust gas. The exhaust gas is fed through a guide grid that forms passages of variable cross-section between the supply channel and a turbine rotor. This guide grid comprises a plurality of vanes of predetermined width in a vane space of about the same width. A vane support ring defines one axial end of the annular vane space and an opposite ring is spaced from the vane support ring by about the width of the vanes to define the other axial end of the annular vane space. To maintain this width, at least two spacers are integrally formed on at least one the rings.

Abstract: A device for controlling variable-pitch vanes in a turbomachine has rods each having at one end a finger for mounting in a control ring and at its other end an assembly orifice for mounting on a drive square of a vane, the axis of the vane being inclined relative to the axis of the finger of the rod, and the assembly orifice in the rod presenting a dimension in the longitudinal direction of the rod that is greater than that of the drive square, and co-operating therewith to define clearance that varies over the height of the drive square and of the orifice.

Abstract: Control lever for the angular setting of a stator blade, comprising a first end intended to be fitted in a fixed manner on a blade pivot, a second end comprising a cylindrical pin for fitting on a control ring, and a flat intermediate part connecting the first and second ends having shapes and dimensions determined in order to increase the natural frequencies of the lever in flexion and in torsion above the vibratory frequencies of the turboshaft engine upstream of the lever and in order to retain the stiffness of the lever.

Abstract: Gas turbine engine systems involving gear-driven variable vanes are provided. In this regard, a representative gas turbine engine system includes: a ring gear assembly operative to be mounted within an engine casing; and a vane module having a first vane airfoil and a first gear, the first gear being operative to engage the ring gear assembly such that movement of the ring gear alters a position of the first vane airfoil.

Abstract: The shape, of a vane for use in a variable nozzle assembly of a turbocharger was designed, including a step of defining a camberline curve and a thickness curve by means of two Bézier curves having a certain number of control points, and a step of applying computational fluid dynamics analysis and a Design of Experiments methodology for optimizing the setting of the control points to improve performance of the vane. As result, a distinct vane shape as shown in the drawings was obtained.

Abstract: A vane system for a centrifugal compressor (10), comprising two rows (15, 20) of vanes (15?, 20?) installed in series inside a suction duct (14), the first row (15) of fixed vanes (15?) being suitable for homogenizing the gas flow that passes through them and sending it to the second row (20) of adjustable vanes (20?) equipped with a guiding mechanism comprising a mechanical system (30) suitable for varying the orientation of the vanes (20?).

Abstract: An article of manufacture having a nominal profile substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in a TABLE 1. Wherein X and Y are distances in inches which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z in inches. The profile sections at the Z distances being joined smoothly with one another to form a complete airfoil shape.

Abstract: A stage of variable-pitch vanes for a turbomachine, these vanes (10) comprising internal pivots engaged in corresponding housings of a sectorized internal ring (12), each ring sector comprising axial orifices for mounting two pins (70, 76) for the radial retention of the ring sector on the internal pivot of a vane, wherein each pin (70, 76) comprises means (72, 78) cooperating by shape coupling with complementary means (78, 72) of the other pin (76, 70) in order to rotationally immobilize these pins in the orifices in the ring sectors.

Abstract: A split shroud system for a gas turbine engine having a pair of annular-shaped shrouds that each have an inner pocket; to form a pair of inner pockets. Each of the pair of pockets having liner parts that form a circle. Liner parts of one of the pair of pockets facing liner parts of the other of the pair of pockets to form liner part pairs. One of each of said of pair of liner parts has a mutual abutting surface that forms a plurality of slots for accepting a plurality of vane inner trunnions.

Abstract: A turbocharger of variable turbine geometry, comprising: a vane bearing ring assembly including a vane bearing ring and a disk which can be fixed to the vane bearing ring for creating a flow channel; and at least one support pin which is connected with a first end to the vane bearing ring and which is welded with a second end to the disk which comprises recesses for the support pin end to be welded, the recesses being surrounded by a heat throttle.

Abstract: A turbine engine includes a plurality of variable fan inlet guide vanes. Where the turbine engine is a tip turbine engine, the variable fan inlet guide vanes permit the ability to control engine stability even though the fan-turbine rotor assembly is directly coupled to the axial compressor at a fixed rate. The fan inlet guide vanes may be actuated from an inner diameter of the fan inlet guide vanes.

Abstract: A turbine section of a gas turbine engine includes a ring of turbine nozzle segments each having paired turbine vanes. Turbine throat area is modulated by rotating each rotational turbine vanes about an axis of rotation which is located such that rotation changes the turbine throat area concurrently between one rotational stator vane and two adjacent fixed turbine vanes. Each paired turbine vane doublet includes at least one rotational turbine vane between two fixed turbine vanes.

Abstract: A bushing assembly for a turbine vane includes a bushing, housing, and a flexible conductor. The bushing includes a bore for receiving a trunnion of the vane and a first conductor extending from the bushing. The first conductor is adapted to be connected to a heater element disposed on the vane. The housing is positioned over the, and the bushing is rotatable relative to the housing. The housing includes a second conductor extending from the housing for connection to an electrical power source.

Abstract: A stator stage of a compressor of a turbomachine, comprising an annular row of variable-pitch vanes, each vane comprising an external cylindrical pivot defining the axis of rotation of the vane, and an internal cylindrical pivot mounted in a housing of an internal ring, the internal pivot of each vane extending along an axis substantially parallel to the axis of rotation of the vane and at a distance from this axis, and being mounted in the housing of the ring by a swiveling or a tilting system.

Abstract: An exhaust turbocharger equipped with a nozzle throat area varying mechanism can be provided in which brazing welding is achieved with a small number of man-hour and at low cost, and which is stable in quality without danger of fracture of brazing-welded parts of constituent members. The variable-throat exhaust turbocharger equipped with a nozzle throat area varying mechanism for varying the blade angle of a plurality of nozzle vanes supported rotatably by members including turbine casing, is characterized in that members having at least one through-hole with at least one shaft member to be inserted into the through-hole(s) to be fixed therein among constituent members of the nozzle throat area varying mechanism are connected by means of brazing welding.

Abstract: A vane ring assembly which includes a lower vane ring (23), an upper vane ring (31), one or more guide vanes (80) positioned at least partially between the vane rings, and a plurality of spacers (49, 50 or 59) positioned between the lower and upper vane rings (23, 31) for maintaining a distance between the lower and upper vane rings, the vane ring assembly being retained in a turbine housing (102) by a retaining ring (400) which is located in a groove (510) in the turbine housing.

Abstract: A variable nozzle device comprises a wall member, a unison ring provided on a first side of the wall member, and a vane, a vane body of which is provided on a second side of the wall member, said second side being opposite to said first side, wherein said vane further having a tab member comprising a tab portion and a shaft portion, said shaft portion being movably inserted in a slot of the wall member; and said tab portion being adapted to hold the vane body by abutting against a portion of the wall member which defines the slot, wherein the vane body and the tab member are provided as separate, parts and are fixable to each other.

Abstract: A variable shape inlet guide vane (IGV) system includes a variable-shape IGV flap with a flexible portion that enables the desired spanwise distribution of Cx, alpha, and beta at a fan rotor inlet. An actuation system that rotates a root section of the variable-shape IGV flap to flex the flexible portion such that the twisted shape of the flap can reverse rather symmetrically during actuation from max open to max closed.

Abstract: A gas turbine engine includes at least one compressor stage with an inner ring under variable angle stator vanes including axial keys for centering the inner ring with respect to the stator vanes, and including at least one sealing member support mounted on the inner ring. The keys include a transverse groove cooperating with a radial rib arranged transverse to the engine axis on the periphery of the support for the sealing member.

Abstract: A securing arrangement 32 for securing an actuating lever 20 to a spindle 14, for example a spindle 14 of a variable inlet guide vane 10 in a gas turbine engine, comprises a fastening formation 38 rotatably co-operable, in use, with a corresponding fastening formation 30 on the spindle 14. The securing arrangement 32 is rotatable relative to the spindle 14 to a securing position in which the respective fastening formations 30, 38 co-operate so that the securing arrangement 32 secures the actuating lever 20 to the spindle 14. The securing arrangement 32 includes anti-rotation means 42, preferably in the form of anti-rotation tabs 44, for preventing rotation of the securing arrangement 32 from the securing position.

Abstract: An attachment system for use with a variable incidence vane is disclosed. The attachment system includes a vane arm for joining a unison ring to a vane spindle. The vane arm has an arm portion and a bushing connected to the arm portion. The attachment system further has a pin for joining the vane arm to the unison ring. The pin fits within an interior bore in the bushing and is joined to the unison ring by a dual swage.

Abstract: A variable stator vane assembly and a bushing thereof. The bushing includes a metal bushing body and a wear-resistant coating. The assembly includes a rotatable trunnion and a first metal bushing. The trunnion is capable of being located in a through hole extending between outer and inner surfaces of a compressor casing of a gas turbine engine. The first metal bushing is capable of being located in the through hole proximate the outer surface to surround a first portion of the trunnion when the trunnion is located in the through hole. The first metal bushing and the first portion have wear-resistant coatings which are in mutual contact, apart from any intervening lubricant, when the trunnion and the first metal bushing are located in the through hole and the trunnion is rotating with respect to the first metal bushing.

Abstract: Within an intake for a gas turbine engine provision is provided through stator vanes 25, 45 in the stator whereby back pressure from a necessary obstruction 34, 46 can be utilised to balance forward pressure variations caused by intake droop or crosswinds in order to reduce those forward pressure detriments for more efficient engine operation according to a desired objective regime. Typically the flow through the intake 20 is analysed and then an appropriate positioning of the stator vanes 25, 45 determined in order to provide approximate balance between the forward pressures and back pressures. Normally, a combination of camber variation of stator vanes 45a and stagger variation of stator vanes 45b are utilised in order to achieve a desired momentum balance around the circumference of the intake 20. It will be understood that both the forward pressures and the back pressures are differentially variable about the circumference such that one opposes the other.

Abstract: A turbine housing of an exhaust gas turbocharger having an adjustable turbine geometry is provided having a carrier ring on which are mounted adjustable guide vanes for regulating the boost pressure and having a cover ring for the guide vanes, whereby the carrier ring and cover ring are spaced a distance apart by means of spacer elements to form a guide vane gap. A fastening screw passes through each spacer element, and screwed into the carrier ring and/or cover ring. Receiving openings for the head of the fastening screw are provided in the carrier ring or cover ring. At least one securing recess is provided in the carrier ring and/or cover ring on the outside circumference of the receiving opening, said securing recess being provided to accommodate material of the screw head to establish a form-fitting connection.

Abstract: The present invention relates to the control of variable-pitch blades, particularly a device for controlling a pivot of a variable-pitch blade in a stator of a turbomachine compressor. The device for controlling a pivot of a variable-pitch blade (1) comprises a control lever (2) and a pivot (3) comprising a bottom end (31) and a top end (32), said top end (32) being connected to the control lever (2). According to the invention, this device is noteworthy in that it comprises two swivel bearings (7), a first swivel bearing (7) being placed at the bottom end (31) of the pivot (3) and a second swivel bearing (7) being placed at the top end (32) of the pivot (3).

Abstract: A variable stator of a turbomachine with a profile skeleton line extending along a meridional flow line, with the stator being radially divided into at least three zones (Z0, Z1, Z2) and with the respective radial inner and the radial outer profile skeleton line of each zone (Z0, Z1, Z2) being designed such that it satisfies the following equations: ? * = ? 1 - ? P ? 1 - ? 2 S * = S P S where: P is any point of the profile skeleton line, ?1 is the angle of inclination at the stator leading edge, ?2 is the angle of inclination at the stator trailing edge, ?* is the dimensionless, specific angle of the total curvature, S* is the dimensionless, specific extension, ?P is the angle of the tangent at any point P of the profile skeleton line to the central meridional flow line, sP is the extension of the profile skeleton line at any point P, and S is the total extension of the profile skeleton line.

Abstract: An actuation system for a plurality of variable stator vanes pivotally mounted in a casing of a compressor. The system includes a plurality of levers each having a proximal end and an opposite distal end. Each of the proximal ends are fixedly coupled to a corresponding stator vane of the plurality of variable stator vanes for pivoting the corresponding stator vane about a stator vane axis. The system also includes an actuation ring coaxially surrounding the casing adjacent the plurality of levers. The actuation ring is coupled to the distal ends of each of the plurality of levers for pivoting the levers as the actuation ring is rotated about a compressor rotation axis. The actuation ring includes a pin extending outward from a radially outward surface of the actuation ring. The system also includes a template comprising a slot for receiving at least a portion of the actuation ring pin.

Abstract: A diffuser includes multiple vanes rotatable about pivot pins between multiple positions. A mounting plate supports a backing plate. The vanes are arranged between the backing plate and the shroud. The pivot pins are in a slip fit relationship with the backing plate, vanes and shroud and are threadingly received by bosses in the mounting plate. The mounting plate and pivot pin arrangement better enables the backing plate and shroud to remain parallel with one another during deflection of the backing plate and/or shroud. Structure, such as integral protrusions and/or bolts, extend from between the backing plate and shroud through apertures in the vanes to better contain the vanes in the event of a catastrophic failure.

Abstract: A variable-throat exhaust turbocharger has a variable throat mechanism that reduces wear of contact surfaces of connection pin parts formed integral with lever plates or a drive ring and the grooves into which the connection pin parts are engaged. A mechanism also prevents slipping out of the drive ring from a nozzle mount toward the lever plate to prevent a probable occurrence of failure in action of the variable throat mechanism caused by the slipping out of the drive ring. The connection pin parts connecting between the lever plates and drive ring of the variable throat mechanism are formed integral with either the lever plates or the drive ring by extrusion or by precision casting. At least the connection pin parts or grooves into each of which each of the connection pin parts, is engaged, are treated with surface hardening including diffusion coating.

Abstract: An exhaust turbocharger with a variable-nozzle mechanism with fail-safe feature included is provided with which, even if wear of the drive ring supporting part where the supporting elements are in reciprocating sliding or rolling contact with each other under high temperature without lubrication increases, the drive ring can be supported on the nozzle mount on the second supporting part, which enables the drive ring to be always supported rightly on the nozzle mount, and to prevent the occurrence of eccentric rotation or dropping out of the drive ring due to excessive wear of the drive ring supporting part or the occurrence of reduction in engine performance due to malfunctions of the variable-nozzle mechanism such as the error in the relation between the output of the actuator and the nozzle vane opening or the occurrence of breakage of the variable-nozzle mechanism as has been experienced in prior arts.

Abstract: A variable-pitch stator vane stage in which the vanes are moved by a rotary actuator ring driven by an electric motor. The outer actuator ring is connected by cranks to the vanes and is constrained to move in rotation only, centered on the axis of the turbomachine; the drive system includes two coaxial portions, an inner portion secured to the casing and an outer portion including the actuator ring, with an electrical drive unit being arranged between the two portions.

Abstract: There is provided a turbocharger with a variable nozzle assembly having a plurality of cambered vanes positioned annularly around a turbine wheel, each vane (20) being pivotable around a pivot point (Pp) and being configured to have a leading edge (Ple) and a trailing edge (Pte) connected by an outer airfoil surface (2) and an inner airfoil surface (4), said outer airfoil surface (2) being substantially convex and said inner airfoil surface (4) having a convex section at the leading edge (Ple) which has a local extreme (Pex) of curvature and transitions into a concave section towards the trailing edge (Pte). The positions of the pivot point (Pp) and the local extreme (Pex) are set such that, even when the vanes are placed in a closed position, the exhaust gas stream exercises a positive torque on the vanes which tends to open the nozzle.

Abstract: A turbomachine having at least one flow path, in which at least one stator blade 2 is arranged, which is variable around a rotational axis 1, and which comprises at its radial end areas one rotary base 3 each, wherein a portion of the rotary base 3 is non-circular, when viewed in a direction of the rotational axis 1 of the stator blade 2.

Abstract: A variable geometry compressor for use in, for example, a turbocharger. A swing-vane diffuser is provided down-stream of the centrifugal compressor wheel. A nozzle ring is adjustable mounted on a center housing, and defines the nozzle face for the compressor diffuser. No spacers are deployed in the diffuser thereby improving efficiency, yet by stacking only the vanes and the nozzle ring, the diffuser clearances are maintained within strict tolerances. Further, seals, such as O-rings, are situated between the nozzle ring and the compressor housing and back plate to eliminate deleterious gas leaks between the diffuser and the spaces behind the nozzle ring.

Abstract: A stator arrangement, or distributor, for a turbine machine is disclosed which includes a guide blade. The blade shaft is supported to be able to pivot around the pivot axis, with a part which is to be guided being situated to the outside. The pivoting device contains a setting ring which is located outside a flow channel and which can be pivoted around the turbine axis, and adjusting levers which transmit torque from the setting ring to the blade shaft of each guide blade. The adjusting lever is slipped with one end onto the blade shaft. The other end can be configured as a ball head, the adjusting levers being guided in a groove of the setting ring. The surface which acts on the ball head of the adjusting lever for transmission of torque from the setting ring to the blade shaft of each guide blade can be configured as a ball socket. Exemplary embodiments can yield a uniform large-area pressure distribution by which the wear of the parts which press on one another can be distinctly reduced.

Abstract: A method enables a variable vane assembly for a gas turbine engine including a casing and an inner shroud to be assembled. The method comprises providing at least one variable vane including a radially inner spindle that has a substantially circular cross-sectional shape, and coupling the variable vane radially between the casing and the inner shroud such that the radially inner spindle is rotatably coupled within an opening extending through the inner shroud, wherein the opening has a non-circular cross-sectional profile.

Abstract: Variable nozzle (10) for a gas turbine fixed to a shaft (11) equipped with a pressurized upper surface (12) and a depressurized lower surface (14) opposite to the upper surface (12), the variable nozzle comprises a series of substantially “C”-shaped sections, each having a first rounded end (20) and a second rounded end (21), each section of the series of sections also having the concavity facing upwards with respect to a base (90) and arranged one after another continuously, in the direction of an axis of the shaft (11) along a curved line (60), the at least second degree curved line (60) lies on a surface (70) having an axis orthogonal to the axis of the shaft (11) and also tilted with respect to the base (90) by an angle (80).

Abstract: A variable stator vane assembly 10 where two downwardly inclined engagement faces 30 are provided on the top of the stator vane upper stem 14, extending for part of the width thereof. A pair of projections 36 with inwardly inclined surfaces 38 are provided on the underside of the lever arm 16. The surfaces 38 are only engageable with the faces 30 in one axial alignment, and otherwise the lever arm 16 will be raised relative to the stator vane 12 to clearly indicate incorrect mounting thereon.

Abstract: A variable geometry inlet guide vane assembly that reduces stress placed on downstream compressor blades in gas turbine engines. The invention circumferential leans upstream guide vanes, pushing engine core air flow radially. This allows for aerodynamic stresses on the downstream blades to be reduced. The invention overcomes the difference in movement between a unison ring and a vane arm by providing a hinge in conjunction with a spherical bearing that couples to the unison ring.

Abstract: The use of spring clamping clips between two adjacent guide vane shafts leads to a defined force on the bearing points of the guide vane in the guide bush. The seating force, resulting from the clamping force and the flow-related lift/drift forces, of the guide vane in the guide bush is therefore always positive and the guide vane rests constantly in the guide bush.

Abstract: A vane assembly includes vanes each having an axle and an arm immovably connected with the vane prior to assembling the vane assembly. The vane, axle, and arm can be an integral one-piece structure formed by casting, machining, or metal injection molding. The axles engage apertures in a nozzle ring and are rotatable in the apertures about axes of the vanes. An actuator ring is assembled with the nozzle ring and is rotatable relative thereto. The actuator ring defines connecting elements that connect with cooperative connecting elements on the vane arms. Rotation of the actuator ring causes the vanes to rotate for adjusting the angles of the vanes. During assembly, the motion of inserting the axles into the apertures is also effective for placing the arms in position for connection with the actuator ring.

Abstract: The invention relates to a variable-pitch control device for a turbomachine compressor, the device comprising a rod, means for fastening a first end of the rod to a pivot of a vane to be controlled, and connection means between a second end of the rod and a control ring. The rod is substantially cylindrical, its first end being engaged in a bore in the pivot of the vane. The device further includes clamping means for clamping the first end of the rod in the bore in the pivot in order to fasten it to said pivot.

Abstract: A turbine unit having a rotor housing (2) having at least one admission channel (9) for a fluid, as well as a turbine rotor (4) which is supported in a turbine space (23) of the rotor housing (2) and wherein fluid is led into the turbine space (23) at its periphery through a VTG mechanism (5-8) of variable turbine geometry. The VTG mechanism (5-8) has a nozzle ring (6) having a plurality of vane shafts (8) which are arranged in the form of a crown on the nozzle ring (6) and which carry on one of their ends vanes (7) which can be moved from a substantially tangential position (relative to the crown) into a substantially radial position, as well as at least one control element (19) in order to pivot the orientation of the vanes (7).

Abstract: A fluid flow engine comprises: a turbine housing including at least one supply channel for supplying a driving fluid; at least one turbine rotor rotatably supported in the turbine housing about an axis of rotation; and a guiding grid of variable turbine geometry radially outside and surrounding the turbine rotor. The guiding grid comprises a nozzle ring forming one end limitation of a vane space and a plurality of guiding vanes each being pivoted about a pivoting axis and being supported by the nozzle ring so as to supply an adjustable amount of fluid from the supply channel to the turbine rotor. At least one spacer is connected to the nozzle ring for securing an axial distance for enabling the vanes to wove freely. The spacer includes at least one bolt or pin tat penetrates into the nozzle ring.

Abstract: A variable pitch stator vane stage, said vanes being moved by an automatically-centered rotary actuator ring. The casing carries a stationary coaxial annular rail projecting from its outside surface, and circumferentially spaced apart moving equipments are provided that are constrained to move along said rail, each moving equipment being coupled to the actuator ring via a radial guide arrangement.

Abstract: A control lever for the pitch angle of a blade in a turbomachine, said lever having a first end intended to be mounted on a blade pivot so as to rotate it and a second end comprising a cylindrical peg for mounting on a control annulus, this peg being fixed by crimping of one of its ends in an orifice of the second end of the lever and comprising an annular flange to which is applied the second end of the lever, wherein stress distribution means are interposed between the second end of the lever and the crimped end of the peg.

Abstract: A variable stator vane assembly for a gas turbine engine including an actuation ring including an upper surface, a lower surface, a first side, a second side, and at least one recess that is defined between the upper surface, the lower surface, the first side, and the second side, a plurality of variable stator vanes, and a lever arm assembly coupled between the actuation ring and at least one of the variable stator vanes, the lever arm assembly including an articulating block inserted at least partially into the actuation ring recess such that the articulating block is movable in a first axis; and a lever arm coupled to the articulating block and at least one of the variable stator vanes such that the lever arm is movable in a second axis that is different than the first axis.

Abstract: A method for fabrication of a locomotive diesel engine turbocharger turbine stage so as to avoid harmonic vibration in the turbine blades when the engine is operated at pre-selected throttle settings. Upon determining throttle settings for the engine and modeling of the turbocharger therefor, at least one natural vibration frequency of the turbine blades and a turbine nozzle vane excitation frequency as a function of turbocharger rotation speed are determined. Then the data obtained is analyzed to ascertain whether at least one data coincidence, that is whether a rotation speed correlative of a throttle setting has a coincidence over a predetermined range of both a natural frequency and said turbine vane nozzle excitation. If not, the model is suitable for fabrication of the turbocharger; if so, the model is modified by changing blade stiffness and/or vane numbering until no data coincidences are present.

Abstract: The preswirl guide device for generating a preswirl in the intake region of a compressor comprises a multiplicity of guide vanes, which are pivotable about a respective vane shank connected to the guide vane, and a pivotable adjusting ring and adjusting levers for transmitting torque from the adjusting ring to the vane shank of each guide vane. The vane shank and the adjusting lever of the respective guide vanes are of one-piece design. The casing in which the guide vanes are rotatably mounted consists of at least two parts joined together in the region of the bearings of the guide vanes. Due to the one-piece design of the guide vane, the number of components to be fitted is reduced. This simplifies the fitting and possible service work on the guide device.