Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
  • F16D3/16—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts
  • F16D3/20—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members
  • F16D3/22—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts
  • F16D3/223—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts the rolling members being guided in grooves in both coupling parts
  • F16D3/224—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts the rolling members being guided in grooves in both coupling parts the groove centre-lines in each coupling part lying on a sphere
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
  • F16D3/16—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts
  • F16D3/20—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members
  • F16D3/22—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts
  • F16D3/223—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts the rolling members being guided in grooves in both coupling parts
  • F16D2003/22313—Details of the inner part of the core or means for attachment of the core on the shaft
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
  • F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
  • F16D3/16—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts
  • F16D3/20—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members
  • F16D3/22—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts
  • F16D3/223—Universal joints in which flexibility is produced by means of pivots or sliding or rolling connecting parts one coupling part entering a sleeve of the other coupling part and connected thereto by sliding or rolling members the rolling members being balls, rollers, or the like, guided in grooves or sockets in both coupling parts the rolling members being guided in grooves in both coupling parts
  • F16D2003/2232—Elements arranged in the hollow space between the end of the inner shaft and the outer joint member

Definitions

• the invention relates to a constant velocity joint comprising an outer joint part with circumferentially distributed longitudinal outer ball tracks, an inner joint part with circumferentially distributed longitudinal inner ball tracks, torque transmitting balls that are seated in pairs of associated outer and inner ball tracks, as well as an annular ball cage is seated between the outer joint part and inner joint part and circumferentially distributed cage windows in which the torque transmitting balls are held in a common plane, wherein the pairs of tracks expand at least in part with the joint extended in a coincident axial direction, the ball cage is axially supported in the outer joint part, and the inner joint part is axially slack compared to Ball cage has and wherein means are provided for resilient support of the inner joint part relative to the outer joint part, which on the inner joint part in relation to the gels Kau jointteil act in the same direction in which expand the pairs of trains.
• Constant velocity joints of the above type are referred to as Rzeppa fixed joints.
• these joints include UF joints (undercut free) with axially undercut-free ball tracks and AC joints (angular contact) with arcuate ball tracks that are axially offset from each other.
• Rzeppa hinges Common to said Rzeppa hinges is the feature that the pairs of tracks of outer and inner ball tracks extend in an extended axial direction when the joint is extended, at least in the joint median plane, sometimes using the term "wedge-shaped widening".
• Constant velocity joints of the type mentioned here are in particular a steering joint, i. therefore particularly suitable for use in the steering column of a motor vehicle in which freedom from play and low drag torque are equally important.
• the basic construction of the joint remains substantially unchanged, and the elements used for resilient axial Ab support can be supplemented after performing corresponding holes in the outer joint part and / or in the inner joint part or in a plugged into this drive shaft without affecting the joint functions.
• the outer joint part comprises a bottom or cover in which a resiliently supported pin is guided coaxially, and that on the inner joint part, an end-side spherical support surface is formed, against which the pin bears with bias.
• the support surface is formed on a support body which is fixedly connected to the inner joint part.
• the support surface is formed on a support body which is inserted into an inserted into the inner joint part drive shaft.
• the outer joint part comprises a bottom or lid in which a coaxially guided pin is resiliently supported, and that on the inner joint part an axially located within the inner ball tracks supporting surface is formed, against which the pin bears with bias.
• the support surface can be arranged in close proximity to the joint center.
• the support surface may be spherical, its vertex lying in the joint center, while the support surface may be calotte-shaped in a second embodiment, its center of curvature being in the center of the joint.
• the abovementioned support surface is formed directly on a drive shaft which is inserted into the inner joint part.
• the outer joint part comprises a bottom or cover in which a coaxial pin is firmly inserted, and that on the inner joint part, a resiliently supported support body is coaxially guided, which rests with a support surface with bias on the pin.
• the support member is guided directly in a drive shaft inserted into the inner joint part and is resiliently, in particular supported by a helical compression spring in the drive shaft.
• the drive shaft and optionally the inner joint part of the support body to the journal widening inwardly.
• the pin and the supporting body each have crowned, in particular outer spherical, contact or support surfaces.
• the pin has a spherical, in particular extruded spherical contact surface and the support body has a planar radial support surface.
• the distance x of a contact region T of the mutual support of the inner joint part and the outer joint part from the joint center M is less than or equal to half the outer diameter D / 2 of the ball cage.
• the distance x is less than or equal to half the inner diameter d / 2 of the ball cage in the joint center plane E, in particular that the distance x is less than or equal to half the outer diameter Di / 2 of Gele ⁇ kinnenteils.
• said Abstützschleppmoment is reduced to an increasing extent.
• the mentioned Abstützschleppmoment can be practically neglected, if in a particular embodiment, the distance x is set to zero.
• the distance x is applied from the center of the joint to the bottom or cover of the outer joint part, but in any case is chosen smaller than in known joints, it is also possible in a modified embodiment that the distance from Joint center point in the direction of the opening side of the outer joint part is offered.
• the surfaces of the supporting elements which are in contact with each other in the contact area T can be formed on the one hand as a convex surface, in particular as an outer sphere, on the other hand as a hollow surface, in particular as an inner sphere, as in the above-mentioned joint.
• both said surfaces are designed as crowned, in particular as outside spherical surfaces.
• FIG. 1 shows a constant velocity universal joint according to the invention in a first embodiment a) in a longitudinal section in an extended position b) in a longitudinal section in an angled position c) in the enlarged detail X according to illustration b;
• Figure 2 shows a constant velocity universal joint according to the invention in a second embodiment a) in a longitudinal section in the extended position b) in a longitudinal section in an angled position c) in the enlarged detail X according to illustration b; d) in the enlarged detail Y according to illustration c;
• FIG. 3 shows a constant velocity universal joint according to the invention in a third embodiment a) in a longitudinal section in an extended position b) in a longitudinal section in an angled position c) in the enlarged detail X according to illustration b; d) in the enlarged detail Y according to illustration c;
• FIG. 4 shows a constant velocity universal joint according to the invention in a fourth embodiment a) in longitudinal section in the extended position b) in the enlarged detail X according to illustration a; c) in the enlarged detail Y according to illustration b;
• FIG. 1 shows a constant velocity universal joint 11 in so-called monoblock construction, in which a bottom 13 and a shaft journal 14 are integrally formed on an outer joint part 12.
• the bottom or a lid could also be used as a separate part and welded or bolted to the outer joint part.
• longitudinal circumferentially distributed outer ball tracks 15 are formed whose center of curvature is offset from a joint center plane E from axially to the opening 16 of the outer joint part 12 out.
• the joint further comprises an inner joint part 17, in which a drive shaft 18 is inserted, wherein the parts (17, 18) are rotatably connected to each other via splines and beyond axially secured against each other.
• Longitudinally distributed inner ball tracks 19 are formed on the inner joint part 17 whose center of curvature is offset in relation to the joint center plane E in the direction of the bottom 13 of the outer joint part 12.
• outer ball tracks 15 and inner ball tracks 19 form pairs of tracks and extend thereafter in the direction from the bottom 13 to the opening 16 of the outer joint part.
• pairs of tracks of outer ball tracks 15 and inner ball tracks 19 receive a torque transmitting ball 31.
• the balls are held by an annular ball cage 22 which is seated between the outer joint part 12 and the inner joint part 17, with their ball centers K in the joint center plane E and guided at flexion of the joint on the bisector plane.
• the balls 31 are in this case received in circumferentially distributed cage windows 23 in the ball cage 22.
• the ball cage 22 has a spherical outer surface 24, which is guided substantially free of play in a innenkugeligen guide surface 20 of the outer joint part 12.
• the inner surface 25 of the ball cage 22, however, has play against an outer surface 21 of the inner joint part 17.
• the outer and inner ball tracks are each described by a circular arc shape, so that the joint is a Rzeppa joint of the type AC (angular contact).
• A12 guided pin 36 is inserted, which is guided in a bore 37 which extends into the shaft journal 14.
• the pin 36 is supported by a helical compression spring 38 in the shaft journal 14 and thus against the outer joint part 12 from.
• the pin 36 has a hemispherical contact surface 39.
• a support body 41 Opposite the pin 36 is located on the inner joint part 17, a support body 41, which is supported with a contact surface 42 on an end face 26 of the inner joint part 17.
• the support body 41 is inserted with a projection 44 in an inner cylindrical bore 27 of the drive shaft 18.
• the support body 41 forms a conspiracykugelige support surface 43, on which the pin 36 acts by means of the contact surface 39 with the force F under bias.
• a contact area T between the pin 36 and the support body 41 always lies close to the longitudinal axis A12 of the outer joint part due to the coaxial arrangement of the pin in the outer joint part, but migrates at a bend of the longitudinal axis A18 of the inner joint part by a Gelenkbeugewinkel ß by the same angle ß from the longitudinal axis L18 on the spherical surface of the support surface 43 of the support body 41.
• the inventive distance x of the contact region T from the joint center M is consistent with spherical shape of the support surface 43 and in any case smaller than the radius D / 2 of the spherical outer surface 24 of the ball cage, preferably smaller than the pitch radius D «/ 2 of the balls and in particular smaller than the radius d / 2 of the inner surface 25 of the ball cage.
• the lever arm R which enters with the force F in the calculation of a support drag torque against the free rotation of the joint in the bent position, increases with the Gelenkbeugewinkel ß.
• the force F as well as the dependence of the lever arm R on the angle ß changes in bending due to the variable deflection of the helical compression spring 38, since the lever arm R is then no pure sine function of ß.
• the support surface 43 is spherical, so that x remains as constant as F.
• the prestressed helical compression spring 38 and thus the pin 36 moves the inner joint part 17 indirectly via the support body 41 to the opening 16 of the outer joint part 12, whereby the inner Ball tracks 19 also act towards the opening on the balls 31.
• the balls 31 are based in this case in the cage windows 23 also from the opening down, whereby the ball cage 22 in turn with its spherical outer surface 24 in the innenkugeligen Inner surface 20 of the outer joint part axially supported. In this way, the joint is free of play.
• the axial distance x of the contact point T from the joint center M is significantly shortened, so that when the joint is bent the lever arm R, which enters into the Abstützschleppmoment against free rotation, is also small.
• FIG. 2 The individual representations of FIG. 2 are described below together, unless particular reference is made to individual representations.
• the figure shows a constant velocity universal joint 11 in so-called monoblock construction, in which a bottom 13 and a shaft journal 14 are integrally formed on an outer joint part 12.
• the bottom or a lid could also be used as a separate part and welded or bolted to the outer joint part.
• longitudinal circumferentially distributed outer ball tracks 15 are formed, the Krümmungsstoffpu ⁇ kt is offset from a joint center plane E from axially to the opening 16 of the outer joint part 12 out.
• the joint further comprises an inner joint part 17, in which a drive shaft 18 is inserted, wherein the parts (17, 18) are rotatably connected to each other via splines and beyond axially secured against each other.
• Longitudinally distributed inner ball tracks 19 are formed on the inner joint part 17 whose center of curvature is offset in relation to the joint center plane E in the direction of the bottom 13 of the outer joint part 12.
• outer ball tracks 15 and inner ball tracks 19 form pairs of tracks and extend thereafter in the direction from the bottom 13 to the opening 16 of the outer joint part.
• pairs of tracks of outer ball tracks 15 and inner ball tracks 19 receive a torque transmitting ball 31.
• the balls are held by an annular ball cage 22 which is seated between the outer joint part 12 and the inner joint part 17, with their ball centers K in the joint center plane E and guided at flexion of the joint on the bisector plane.
• the balls 31 are in this case received in circumferentially distributed cage windows 23 in the ball cage 22.
• the ball cage 22 has a spherical outer surface 24 which is substantially free of play in a innenkugeligen guide surface 20 of the outer joint part 12th to be led.
• the inner surface 25 of the ball cage 22, however, has play against an outer surface 21 of the inner joint part 17.
• the outer and inner ball tracks are each described by a circular arc shape, so that the joint is a Rzeppa joint of the type AC (angular contact).
• a coaxial with the longitudinal axis A12 guided pin 36 2 is inserted, which is guided in a bore 37 which extends into the shaft journal 14.
• the pin 36 is supported via a helical compression spring 38 in the shaft journal 14 and thus from the outer joint part 12.
• the pin 36 has a hemispherical contact surface 39 second
• the pin 36 2 oppositely located at the inner joint part 17 and in this inserted drive shaft 18 is an inwardly tapered extension 28.
• a Swisskugelige support face 43 2 is formed with a small radius at which the pin 36 2 by means of the contact surface 39 2 the force F acts under prestress.
• a contact area T between the journal 36 2 and the support surface 43 2 always lies close to the longitudinal axis A12 of the outer joint part due to the coaxial arrangement of the pin in the outer joint part, but migrates when the longitudinal axis A18 of the inner joint part is bent a Gelenkbeugewinkel ß by the same angle ß from the longitudinal axis A 18 on the spherical support surface 43 second
• the distance x according to the invention of the contact region T from the joint center M is in this case equal to zero.
• the lever arm R which enters with the force F in the calculation of a Abstützschleppmomentes against the free rotation of the joint in the bent position, is negligible.
• the preloaded compression spring 38 and thus the pin 36 2 displaces the inner joint part 17 indirectly via the drive shaft 18 to the opening 16 of the outer joint part 12, whereby the inner ball tracks 19 also act on the balls 31 towards the opening.
• the balls 31 are also supported in the cage windows 23 towards the opening, whereby the ball cage 22 in turn is axially supported with its spherical outer surface 24 in the inner spherical inner surface 20 of the outer joint part. In this way, the joint is free of play.
• the axial distance x of the contact point T from the joint center M is equal to zero, so that when bent joint of the lever arm R, in the Abstützschleppmoment against free Turning is negligible.
• the figure shows a constant velocity universal joint 11 in so-called monoblock construction, in which a bottom 13 and a shaft journal 14 are integrally formed on an outer joint part 12.
• the bottom or a lid could also be used as a separate part and welded or bolted to the outer joint part.
• outer joint part 12 longitudinally distributed circumferentially distributed outer ball tracks 15 are formed whose center of curvature is offset from a joint center plane E from axially to the opening 16 of the outer joint part 12 out.
• the joint further comprises an inner joint part 17, in which a drive shaft 18 is inserted, wherein the parts (17, 18) are rotatably connected to each other via splines and beyond axially secured against each other.
• Longitudinally distributed inner ball tracks 19 are formed on the inner joint part 17 whose center of curvature is offset in relation to the joint center plane E in the direction of the bottom 13 of the outer joint part 12.
• outer ball tracks 15 and inner ball tracks 19 form pairs of tracks and extend thereafter in the direction from the bottom 13 to the opening 16 of the outer joint part.
• pairs of tracks of outer ball tracks 15 and inner ball tracks 19 receive a torque transmitting ball 31.
• the balls are held by an annular ball cage 22 which is seated between the outer joint part 12 and the inner joint part 17, with their ball centers K in the joint center plane E and guided at flexion of the joint on the bisector plane.
• the balls 31 are in this case received in circumferentially distributed cage windows 23 in the ball cage 22.
• the ball cage has a spherical outer surface 24, which is guided substantially free of play in a innenkugeligen guide surface 20 of the outer joint part 12.
• the inner surface 25 of the ball cage 22, however, has play against an outer surface 21 of the inner joint part 17.
• the outer and inner ball tracks are each described by a circular arc shape, so that the joint is a Rzeppa joint of the type AC (angular contact).
• a coaxial with the longitudinal axis A12 guided pin 36 3 is inserted, which is guided in a bore 37 which extends into the shaft journal 14.
• the pin 36 3 is supported via a helical compression spring 38 in the shaft journal 14 and thus from the outer joint part 12.
• the pin 36 has a hemispherical contact surface 39 3rd
• the pin 36 3 opposite is located on the inner joint part and inserted into this drive shaft 18, a conical widening 28.
• a contact area T between the pin 36 3 and the support surface 43 3 always lies close to the longitudinal axis A12 of the outer joint part due to the coaxial arrangement of the pin in the outer joint part, but migrates at a bend of the longitudinal axis A18 of the inner joint part by a Gele ⁇ kbeugewinkel ß to the same angle ß from the longitudinal axis A 18 on the ball surface 43 of the plug 41.
• the inventive distance x of the contact region T from the joint center M is in this case applied to the opening 16 of the outer joint part.
• the lever arm R which enters with the force F in the calculation of a Abstützschleppmomentes against the free rotation of the joint in the bent position, this is very small.
• the preloaded compression spring 38 and thus the pin 36 3 displaces the inner joint part 17 indirectly via the drive shaft 18 to the opening 16 of the outer joint part 12, whereby the inner ball tracks 19 also act on the balls 31 towards the opening.
• the balls are also supported in the cage windows 23 from the opening, whereby the ball cage 22 in turn is axially supported with its spherical outer surface 24 in the inner spherical inner surface 20 of the outer joint part. In this way, the joint is free of play.
• the axial distance x of the contact point T from the joint center M is significantly shortened, so that when the joint is bent, the lever arm R, which enters the support drag torque against free rotation, is also small.
• FIG. 4 shows a Gleichiauffangelenk 11 in so-called monoblock construction, in which at a joint outer part 12, a bottom 13 and a shaft journal 14 are integrally formed.
• the bottom or a lid could also be used as a separate part and welded or bolted to the outer joint part.
• longitudinal circumferentially distributed outer ball tracks 15 are formed whose center of curvature is offset from a joint center plane E from axially to the opening 16 of the outer joint part 12 out.
• the joint further comprises an inner joint part 17, in which a drive shaft 18 is inserted, wherein the parts (17, 18) are rotatably connected to each other via splines and überhi are axially secured against each other.
• Longitudinally distributed inner ball tracks 19 are formed on the inner joint part 17 whose center of curvature is offset in relation to the joint center plane E in the direction of the bottom 13 of the outer joint part 12.
• outer ball tracks 15 and inner ball tracks 19 form pairs of tracks and extend thereafter in the direction from the bottom 13 to the opening 16 of the outer joint part.
• pairs of tracks of outer ball tracks 15 and inner ball tracks 19 receive a torque transmitting ball 31.
• the balls are held by an annular ball cage 22 which is seated between the outer joint part 12 and the inner joint part 17, with their ball centers K in the joint center plane E and guided at flexion of the joint on the bisector plane.
• the balls 31 are in this case received in circumferentially distributed cage windows 23 in the ball cage 22.
• the ball cage has a spherical outer surface 24, which is guided essentially free of play in an inner spherical guide surface 20 of the outer joint part 12.
• the inner surface 25 of the ball cage 22, however, has play against an outer surface 21 of the inner joint part 17.
• the outer and inner ball tracks are each described by a circular arc shape, so that the joint is a Rzeppa joint of the type AC (angular contact).
• pin 36 4 In the bottom 13 of the outer joint part 12 a coaxially to the longitudinal axis A12 arranged pin 36 4 is firmly inserted.
• the pin 36 4 has a hemispherical contact surface 39 4th
• the pin 36 4 opposite is located on the inner joint part Supporting body 41 4 , which is guided in a bore 29 and is supported via a helical compression spring 30 in the drive shaft 18 and thus relative to the inner joint part 17.
• the support body 41 4 forms an outer spherical support surface 43 4 , which acts on the pin 36 4 via the contact surface 39 4 with the force F under bias.
• the support surface 43 4 as well as the contact surface 39 4 is spherical, is in the Detail Y according to illustration c a radially planar support surface 43 4 'shown, which cooperates with a spherical contact surface 39 4 .
• the distance x according to the invention of the contact region T from the joint center M is thus again equal to zero.
• the lever arm R which enters with the force F in the calculation of a Abstützschleppmomentes against the free rotation of the joint in the bent position, is negligible.
• the prestressed helical compression spring 30 displaces the inner joint part 17 indirectly via the drive shaft 18 toward the opening 16 of the outer joint part 12, whereby the inner ball tracks 19 likewise act on the balls 31 towards the opening.
• the balls are also supported in the cage windows 23 to the opening, whereby the ball cage 22 in turn is axially supported with its spherical outer surface 24 in the inner spherical inner surface 20 of the outer joint part 12. In this way, the joint is free of play.
• the axial distance x of the contact point T from the joint center M is equal to zero, so that when the joint is bent the lever arm R, which enters into the Abstitzschleppmoment against free rotation, is negligible.
• the balls should preferably be installed squeeze-free in the cage windows.

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• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Pivots And Pivotal Connections (AREA)

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• 2006
  • 2006-04-07 DE DE102006016867.4A patent/DE102006016867B4/de active Active
• 2007
  • 2007-03-01 WO PCT/EP2007/001755 patent/WO2007115606A1/de active Application Filing
  • 2007-03-01 CN CN2007800117494A patent/CN101421528B/zh active Active
  • 2007-03-01 RU RU2008144123/11A patent/RU2422691C2/ru active

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