• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The invention relates to a method for manufacturing a pulley device (1) for a tensioning or winding roller of a transmission element comprising a pulley (2), at least two bearings (6, 10) and a sleeve (14). the bearings (6, 10) being successively mounted adjacent to said sleeve (14) before the pulley (2) is formed by injection of material onto said bearings (6, 10).
    公开号:FR3039864A1
    申请号:FR1557575
    申请日:2015-08-06
    公开日:2017-02-10
    发明作者:Daniel Capoldi；Frederic Bordier；Laurent Cherioux；Thierry Prouteau；Philippe Weber
    申请人:SKF AB；
    IPC主号:
    专利说明:

    Method of manufacturing a pulley device, pulley device according to such a manufacturing method and engine equipped with such a pulley
    Description
    The present invention relates to a manufacturing method for a pulley device for a tensioning roller or winder intended to cooperate with a transmission element, for example a chain or a timing belt of a motor vehicle internal combustion engine. The invention also relates to an engine equipped with such a pulley device.
    Such a roller is generally used to permanently maintain a tension on the transmission element, such as a belt or a chain, in a specific range or to locally change the path taken by it. We then speak respectively of tensioner roller or roller winder.
    In a roller, a pulley is rotatably mounted on a screw or a shaft via a bearing, the roller being then attached directly or indirectly to a motor unit or to a member of a tensioner device, for example an articulated arm or an eccentric.
    The bearing is a mechanical device for implementing a pivot connection between the pulley and the screw or the axis. For this purpose, the bearing may be a bearing.
    It is known to provide a roller bearing equipped with an inner ring, an outer ring surmounted by the pulley and a row of rolling elements, for example balls, housed radially between defined bearing paths on each of the rings.
    To support higher loads, the bearing can be equipped with at least two rows of rolling elements. Alternatively, the roller may be equipped with at least two single-row rolling element bearings.
    However, the use of a plurality of axially adjacent bearings requires the use of an interference-mounted pulley on the outer rings of the bearings, as described for example in WO 01/33108 A1. Indeed, due to tolerances and manufacturing defects of the elements of each bearing, there are axial and radial misalignment even between two bearings supposed to be identical. A pulley mounted tight on the outer rings of the axially adjacent bearings makes it possible to make up for misalignments between said outer rings.
    A pulley made of metal or rigid plastic can then be used for this purpose, said inner rings of the bearings being mounted in an inner cylindrical surface of a central bore of the pulley.
    However, such a constraint prevents the manufacture of a pulley by injection of material on the outer rings of the bearings. Indeed, in this case the misalignment can not be caught by the pulley since the material constituting said pulley is only deposited and fits the rings. A pulley material less rigid, less massive, less expensive is appropriate. The overmolding process, controlled by those skilled in the art and inexpensive, is also not appropriate. The object of the present invention is to provide a new method of manufacturing pulley device particularly simple and economical to implement. To this end, the invention relates to a method of manufacturing a pulley device for tensioner roller or winder of a transmission element.
    According to the invention, the device comprises a pulley, at least two bearings and a sleeve and the method comprises the following successive steps: (a) At least two single-row rolling element bearings are previously assembled, said bearings comprising each an inner ring provided with a bore, an outer ring provided with an outer cylindrical surface, and a single row of rolling elements housed radially between the inner and outer rings, said rings being able to rotate relative to a central axis ; (b) A sleeve is placed in coaxial position with the bearings; (c) The at least two single-row bearings of rolling elements are successively mounted on an outer cylindrical surface of the sleeve, the inner rings of the bearings being in axial bearing with each other successively, said sleeve being common to all inner rings of the bearings, and such that the outer cylindrical surface of the sleeve interferes with the inner bearing bores of the axially adjacent bearings; and (d) A plastics material pulley is formed by injecting material onto the outer cylindrical surfaces of the outer races of the bearings.
    Thanks to the invention, the inner rings of the adjacent bearings are all positioned and adjusted relative to the outer cylindrical surface of the sleeve. Relative axial and radial misalignments between said rings are compensated for by cylindricity of the outer surface of the sleeve. Such cylindricity is relatively easy to manufacture for the skilled person.
    As a result, a pulley is formed by injection of material onto the outer rings of the adjacent bearings which, in the previous step, have all been adjusted relative to one another. The injection method deposits a material that marries the outer surfaces and any gaps between the outer rings of the bearings, said interstices having been limited by the previous step of positioning and adjustment.
    Thus, the invention makes it possible to replace the use of a multi-row bearing by a plurality of single-row bearings while retaining the technical advantages, in equivalent number of rows of rolling elements. In addition, a multi-row bearing has a higher cost and manufacturing accuracy compared to several single row bearings, in equivalent number of rows of rolling elements. The invention also relates to a pulley device for tensioning roller or retractor obtained by such a manufacturing method.
    According to advantageous but non-mandatory aspects of the invention, a stop device obtained by such a manufacturing method may incorporate one or more of the following features taken in any technically permissible combination:
    The rolling elements of the bearing are balls.
    The rolling elements of the bearing are held more or less evenly spaced circumferentially by a cage.
    The pulley is made of a material that can be injected, cast or molded, for example plastic.
    The pulley is made of polyamide PA66 with 30% fiberglass. The pulley comprises an outer axial portion intended to cooperate with a transmission element, an inner axial portion, surmounting the outer rings of the bearings, and a radial annular intermediate portion connecting said axial portions.
    The pulley comprises stiffening ribs provided between the inner and outer axial portions and connected to the intermediate portion.
    The inner axial portion of the pulley comprises two shoulders directed radially inwardly of the pulley device, said shoulders being positioned axially on either side of the assembly formed by the bearings of the pulley device so that the rings adjacent outer bearings are retained axially by said shoulders.
    The inner axial portion of the pulley is extended at an axial end by fastening means for cooperating with a cover.
    The attachment means for a lid consist of an annular axial portion provided with a relief intended to be housed in an associated cavity of said lid.
    The relief is annular.
    The sleeve is made of steel.
    The sleeve is sintered steel D10 with bonding agent.
    The sleeve comprises a tubular portion provided with the outer cylindrical surface on which the bearings are mounted, said tubular portion being extended at an axial end by an annular radial flange of larger diameter.
    The outer diameter of the flange of the sleeve does not extend more than 90% of the inside diameter of the pulley so as to leave a free radial space between said flange and said pulley for closing a mold on the outer rings of the bearings during the overmolding process of the pulley.
    The sleeve is provided with a bore for supporting a screw or shaft.
    The sleeve is provided with fixing means intended to be mounted integrally on a support. The invention also relates to an internal combustion engine comprising at least one tensioner roller device or winder for torque transmission element according to one of the embodiments mentioned above. The invention will be better understood and other advantages thereof will appear more clearly in the light of the following description of a single embodiment of a pulley device according to its principle, given only as a example and with reference to the accompanying drawings showing an axial half-sectional view of such a pulley device.
    A pulley device for a tensioner or retractor roller of a transmission element, referenced 1 as a whole, comprises a pulley 2, two rolling bearings 6 and 10, and a sleeve 14.
    The pulley 2 comprises an inner axial portion 3, an outer axial portion 5 and an intermediate annular radial portion 4 connecting said inner 3 and outer portions 5. The pulley 2 as a whole, and the portions 3, 4, 5 constituting in particular , are annular along a central axis X1. Ribs 4a of stiffening are provided between the inner axial portions 3 and outer 5 and are connected to the intermediate portion 4.
    The outer axial portion 5 of the pulley 2 has an outer cylindrical surface 5a intended to cooperate with a transmission element 17 shown in dashed line, for example a belt or a chain.
    The inner axial portion 3 of the pulley 2 has an axial end 3d extending axially by fixing means 3e for cooperating with a cover 18, shown in dashed line. The axial end is annular and the fixing means consist of an annular relief 3e intended to be housed in an associated groove of a cover. Alternatively, the fixing means may consist of gluing, or any other suitable means.
    The inner axial portion 3 of the pulley 2 has a bore 3a in which are housed two rolling bearings 6, 10.
    The rolling bearing 6 comprises an outer ring 7 provided with two radial front edges 7a, 7b, an outer cylindrical surface 7c and a bore 7d, and an inner ring 8 provided with two radial front edges 8a, 8b, d an outer cylindrical surface 8c and a bore 8d.
    The rolling bearing 6 comprises a single row of rolling elements 9, here made in the form of balls, arranged between toroidal raceways provided at the bore 7d of the outer ring 7 and the outer cylindrical surface 8c of the ring. inside 8.
    The rings 7, 8 of the rolling bearing 6 can be in relative rotation around the central axis X1.
    Similarly, the rolling bearing 10 comprises an outer ring 11 provided with two radial front edges 11a, 11b, an outer cylindrical surface 11c and a bore 11d, and an inner ring 12 provided with two radial front edges. 12a, 12b, an outer cylindrical surface 12c and a bore 12d.
    The rolling bearing 10 comprises a single row of rolling elements 13, here made in the form of balls, arranged between toroidal raceways provided at the bore 11d of the outer ring 11 and the outer cylindrical surface 12c of the ring. inside 12.
    The rings 11, 12 of the rolling bearing 10 may be in relative rotation around the central axis X1.
    In the exemplary embodiment illustrated, the outer rings 7, 11 and inner 8, 12 are massive, that is to say whose shape is obtained by machining with removal of chips (turning, grinding) from tubes, bars, forged blanks and / or rolled.
    The rolling elements 9, 13 may be housed in a cage, not shown, ensuring the maintenance of the circumferential spacing of the rolling elements.
    The rolling bearings 6, 10 may each comprise one or two annular sealing means, not shown, on each side of the single row of rolling elements.
    According to the invention, rolling bearings 6, 10 with a single row of rolling elements 9, 13 respectively are axially adjacent.
    The outer rings 7, 11 and inner rings 8, 12 of the two bearings 6, 10 are adjacent axially respectively, so that the radial front edges 7b, 11a of the outer rings 7, 11 and the radial front edges 8b, 12a of the inner rings. 8, 12 are axially supported.
    The rolling bearings 6, 10 are both radially housed in the pulley 2. More specifically, the outer cylindrical surfaces 7c, 11c of the outer rings 7, 11 of the rolling bearings 6, 10 respectively are in contact with the bore 3a of FIG. the inner axial portion 3 of the pulley 2.
    The inner axial portion 3 of the pulley 2 comprises two shoulders 3b, 3c directed radially inwardly of the pulley device 1, said shoulders 3b, 3c being positioned axially on either side of the assembly formed by the bearings. Bearings 6, 10 of the stop device 1. The shoulder 3b is axially in abutment against the radial front edge 11b of the outer ring 11 of the rolling bearing 10 and the shoulder 3c is axially in abutment against the radial front edge 7a of the outer ring 7 of the rolling bearing 6. Thus the outer rings 7, 11 axially adjacent to the rolling bearings 6, 10 are retained axially by said shoulders 3b, 3c of the pulley 2.
    The inner rings 8, 12 axially adjacent to the rolling bearings 6, 10 have adjacent bores 8d, 12d in which a sleeve 14 is housed.
    The sleeve 14, of central axis X1, comprises a cylindrical axial portion 15 having an outer cylindrical surface 15a on which are fitted the bores 8d, 12d of the inner rings 8, 12 of the bearings 6, 10 respectively.
    The cylindrical axial portion is extended at one of its axial ends by an annular radial flange 16 of larger diameter. The flange covers on one side the free radial space between the bore 11 d of the outer ring 11 and the outer cylindrical surface 12c of the inner ring 12 so as to prevent the entry of polluting elements from outside. of the device 1.
    The flange 16 also forms an axial abutment surface against which comes axially bearing the radial front edge 12b of the inner ring 12 of the rolling bearing 10.
    The inner ring 8 of the other rolling bearing 6 of the device 1 also bearing against said inner ring 12 of the rolling bearing 10, the flange 16 serves as a reference for the adjustment in axial positioning of the adjacent inner rings in support.
    Furthermore, the flange 16 may come axially in abutment against an outer support, not shown, the pulley device 1 to allow mounting and fixing the device 1 on said support. The support may be for example a motor unit, an articulated or eccentric arm of the associated automatic tensioner roller. For this purpose, the sleeve 14 as a whole is provided with a through bore 15b in which can be inserted a screw for securing the pulley device 1 to said support.
    According to the invention, the device 1 is mounted by the following successive steps.
    The two rolling bearings 6 and 10 single row of rolling elements are previously assembled, said bearings 6, 10 each comprising an inner ring 8, 12 provided with a bore 8d, 12d respectively, an outer ring 7, 11 provided with an outer cylindrical surface 7c, 11c respectively, and a single row of rolling elements 9, 13 housed radially between the inner rings 8, 12 and outer 7, 11 respectively, said rings 7, 8 and 11, 12 being rotatable relative to the central axis X1.
    The sleeve 14 is placed in co-axial position with the rolling bearings 6, 10.
    The two rolling bearings 6, 10 with single row of rolling elements are successively mounted on the outer cylindrical surface 15a of the cylindrical axial portion 15 of the sleeve 14, said axial portion 15 being common to all of the inner rings 8, 12 bearings 6, 10 respectively. The outer cylindrical surface 15a of the axial portion 15 interferes with the bores 8d, 12d of the inner rings 8, 12 of the axially adjacent bearings 6, 10.
    More specifically, the inner rings 8, 12 have their position adjusted on the cylindrical portion 15 to bear axially. In addition, the inner ring 12 of the bearing 10 also bears axially against the flange 16 extending radially from the axial portion 15 of the sleeve, in order to form a positioning reference and a stop for the inner rings 8, 12. consequently, the outer rings 7, 11 come close to one another to an axial support.
    The pulley 2 made of plastic material is then overmolded on the assembly formed by the outer rings 7, 11 of the bearings 6, 10.
    The pulley may advantageously be made of plastic, for example of polyamide PA66 reinforced with 30% glass fiber.
    According to an alternative not shown, the device 1 may comprise more than two axially adjacent bearing bearings.
    Preferably, the outer diameter of the flange 16 of the sleeve 14 does not extend more than 90% of the inside diameter of the pulley 2, in particular of the shoulder 3b, so as to leave a free radial space between said flange 16 and said pulley 2 for closing a mold on the outer rings 7, 11 of the bearings 6, 10 during the overmolding process of the pulley 2. The invention is described above in the case of the use of ball bearings. It can also be used with other rolling elements, in particular pebbles or needles.
    The technical characteristics of the embodiments and variants envisaged above can be combined with each other.
    权利要求:
    Claims (8)
    [1" id="c-fr-0001]
    claims
    A method of manufacturing a pulley device (1) for a tensioning or winding roller of a transmission element comprising a pulley (2), at least two bearings (6, 10) and a sleeve (14), said method comprising the following successive steps: (a) At least two rolling-element single-row bearings (6, 10) are pre-assembled, said bearings (6, 10) each comprising an inner ring (8, 12) provided with a bore (8d, 12d), an outer ring (7, 11) provided with an outer cylindrical surface (7c, 11c), and a single row of rolling elements (9, 13) radially fitted between the inner rings (7, 11) and outer (8, 12), said rings (7, 11; 8, 12) being able to rotate relative to a central axis (X1); (b) A sleeve (14) is placed in a coaxial position with the bearings (6, 10); (c) The at least two rolling element single-row bearings (6, 10) are successively mounted on an outer cylindrical surface (15a) of the sleeve (14), the inner rings (8, 12) of the bearings (6, 10) being in axial bearing with each other successively, said sleeve (14) being common to all of the inner rings (8, 12) of the bearings (6, 10), and so that the outer cylindrical surface ( 15a) of the sleeve (14) interferes with the bores (8d, 12d) of the inner rings (8, 12) of the axially adjacent bearings (6, 10); and (d) A plastics material pulley is formed by injecting material onto the outer cylindrical surfaces (7c, 11c) of the outer rings (7, 11) of the bearings (6, 10).
    [2" id="c-fr-0002]
    2. A pulley device made by the manufacturing method of claim 1.
    [3" id="c-fr-0003]
    3. pulley device according to claim 1, characterized in that the pulley (2) comprises an inner axial portion (3) provided with two shoulders (3b, 3c) directed radially inwardly of the pulley device (1), said shoulders (3b, 3c) being positioned axially on either side of the assembly formed by the bearings (6, 10) of the pulley device (1) so that the adjacent outer rings (7, 11) of the bearings (6, 10) are retained axially by said shoulders (3b, 3c).
    [4" id="c-fr-0004]
    4. pulley device according to one of claims 2 or 3, characterized in that the pulley (2) comprises an inner axial portion (3) extended at an axial end (3d) by fastening means (3c) for cooperate with a lid (18).
    [5" id="c-fr-0005]
    Pulley device according to one of Claims 2 to 4, characterized in that the sleeve (14) comprises a tubular portion (15) provided with the outer cylindrical surface (15a) on which the bearings (6, 10), said tubular portion (15a) being extended at an axial end by an annular radial flange (16) of larger diameter.
    [6" id="c-fr-0006]
    A pulley device according to claim 5, characterized in that the outer diameter of the flange (16) of the sleeve (14) does not extend more than 90% of the inside diameter of the pulley (2) so as to leave a free radial space between said flange (16) and said pulley (2) for closing a mold on the outer rings (7, 11) of the bearings (6, 10) during the overmoulding process of the pulley (2) .
    [7" id="c-fr-0007]
    Pulley device according to one of Claims 2 to 6, characterized in that the sleeve (14) is provided with a bore (15a) for supporting a screw or an axle.
    [8" id="c-fr-0008]
    Internal combustion engine comprising at least one pulley device (1) for a tensioning or winding roller for a transmission element according to any one of claims 2 to 9.
    类似技术:
    公开号 | 公开日 | 专利标题
    FR2923281A1|2009-05-08|ROLLER OR ROLLER DEVICE
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    FR3039864A1|2017-02-10|METHOD OF MANUFACTURING A PULLEY DEVICE, PULLEY DEVICE ACCORDING TO SUCH A MANUFACTURING PROCESS AND MOTOR EQUIPPED WITH SUCH PULLEY
    FR2865008A1|2005-07-15|Motor vehicle suspension strut thrust bearing has seal attached to cover by series of projections
    FR3029586A1|2016-06-10|PULLEY DEVICE
    FR3035928A1|2016-11-11|PULLEY DEVICE FOR TILT ROLLER OR ROLLER
    FR3037115A1|2016-12-09|PULLEY DEVICE FOR TILT ROLLER OR ROLLER
    FR2998937A1|2014-06-06|GEAR REDUCER WITH SEALING PLUG ENSURING THE AXIAL RETENTION OF A RATTRAPAGE SPRING OF THE CHANGING GAME.
    CA2887798A1|2015-10-11|Pulley device for belt or chain, manufacturing process for a hollow shaft for such a device and assembly method for a device
    FR3018887A1|2015-09-25|ROLLER OR ROLLER DEVICE
    FR3018886A1|2015-09-25|ROLLER OR ROLLER DEVICE
    FR3080421A1|2019-10-25|PULLEY DEVICE FOR TILT ROLLER OR ROLLER
    FR3039863A1|2017-02-10|PULLEY DEVICE FOR TILT ROLLER OR ROLLER
    FR2989755A1|2013-10-25|WEAR COMPENSATION DEVICE FOR GEAR AND ASSOCIATED MOUNTING METHOD.
    FR3008148A1|2015-01-09|BEARING BEARING DEVICE, IN PARTICULAR FOR STEERING COLUMN
    FR2782758A1|2000-03-03|Roller bearing for motor vehicle steering column, comprises an electrically conductive tolerance collar between the bearing race and the interior surface of the steering column
    FR3090060A1|2020-06-19|Pulley device
    EP2053248A2|2009-04-29|Belt drive mechanism and its manufacturing method
    FR2780117A1|1999-12-24|Roller bearing for steering column of vehicle
    FR3086027A1|2020-03-20|PULLEY DEVICE FOR TENSIONER OR ROLLER
    EP1162379B1|2007-07-18|Belt tensioning pulley
    FR3098875A1|2021-01-22|Pulley device
    FR3099219A1|2021-01-29|Pulley device
    FR2779787A1|1999-12-17|Compensating ring for especially bearing of motor vehicle steering column
    FR3020108A1|2015-10-23|ROLLER OR ROLLER DEVICE
    同族专利:
    公开号 | 公开日
    BR102016018003A2|2017-04-04|
    CN106438945B|2021-07-09|
    CN106438945A|2017-02-22|
    DE102016214261A1|2017-02-09|
    US20170036409A1|2017-02-09|
    US10493712B2|2019-12-03|
    FR3039864B1|2018-02-16|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    US3746413A|1971-03-25|1973-07-17|Wada Seiko K K|Rotation preventive device|
    DE4420669A1|1994-06-14|1995-01-12|Impact Immobilien & Consulting|Supporting, guiding, beating or deflecting rollers|
    DE29711143U1|1997-06-26|1998-10-29|Sachsenring Entwicklungsgesell|Bearing, especially for a jig|
    DE10035488A1|2000-07-21|2002-01-31|Schaeffler Waelzlager Ohg|Method for mounting pulley for belt drive using two plastic sleeves with a snap fastening|
    JP2002181167A|2000-12-19|2002-06-26|Koyo Seiko Co Ltd|Pulley unit|
    DE10333673A1|2003-07-24|2005-02-17|Ina-Schaeffler Kg|Tension pulley for belt used in engine of vehicle, comprising sealing cap securing components of pulley unit|
    JP2006161950A|2004-12-07|2006-06-22|Jtekt Corp|Pulley device|
    DE102007015332A1|2007-03-30|2008-10-02|Schaeffler Kg|traction drive|
    JP2009041584A|2007-08-06|2009-02-26|Nsk Ltd|Manufacturing method of resin pulley with rolling bearing, resin pulley with rolling bearing, and molding mold|
    FR2923281A1|2007-11-06|2009-05-08|Skf Ab|ROLLER OR ROLLER DEVICE|
    AU1227401A|1999-10-29|2001-05-14|Dayco Products, Inc.|Pulley assembly|
    FR2932863B1|2008-06-23|2010-12-10|Skf Ab|PULLEY DEVICE FOR TENDER ROLLER OR ROLLER.|
    FI122663B|2009-02-10|2012-05-15|Kone Corp|A method for mounting a double bearing in a casting and a wheel having a double bearing|US10274013B2|2011-11-16|2019-04-30|Roller Bearing Company Of America, Inc.|Cam follower with tire having axial movement compensating features|
    FR3078758B1|2018-03-06|2020-04-03|Aktiebolaget Skf|PULLEY DEVICE FOR TENSIONER OR ROLLER|
    CN110744848A|2019-10-30|2020-02-04|江阴普菲特电梯部件有限公司|Production method of escalator roller|
    法律状态:
    2016-08-25| PLFP| Fee payment|Year of fee payment: 2 |
    2017-02-10| PLSC| Search report ready|Effective date: 20170210 |
    2017-08-28| PLFP| Fee payment|Year of fee payment: 3 |
    2018-08-29| PLFP| Fee payment|Year of fee payment: 4 |
    2019-08-28| PLFP| Fee payment|Year of fee payment: 5 |
    2020-08-24| PLFP| Fee payment|Year of fee payment: 6 |
    2021-08-30| PLFP| Fee payment|Year of fee payment: 7 |
    优先权:
    申请号 | 申请日 | 专利标题
    FR1557575|2015-08-06|
    FR1557575A|FR3039864B1|2015-08-06|2015-08-06|METHOD OF MANUFACTURING A PULLEY DEVICE, PULLEY DEVICE ACCORDING TO SUCH A MANUFACTURING PROCESS AND MOTOR EQUIPPED WITH SUCH PULLEY|FR1557575A| FR3039864B1|2015-08-06|2015-08-06|METHOD OF MANUFACTURING A PULLEY DEVICE, PULLEY DEVICE ACCORDING TO SUCH A MANUFACTURING PROCESS AND MOTOR EQUIPPED WITH SUCH PULLEY|
    CN201610622355.3A| CN106438945B|2015-08-06|2016-08-01|Method for manufacturing pulley device, pulley device and pulley-equipped engine|
    DE102016214261.5A| DE102016214261A1|2015-08-06|2016-08-02|A method of manufacturing a pulley device, pulley device according to such a manufacturing method, and motor equipped with such a pulley|
    BR102016018003A| BR102016018003A2|2015-08-06|2016-08-03|method for manufacturing a pulley device, a pulley device according to such a manufacturing method and a motor equipped with such a pulley|
    US15/230,897| US10493712B2|2015-08-06|2016-08-08|Method for manufacturing a pulley device, a pulley device according to such a manufacturing method and an engine fitted with such a pulley|
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