WO2003078240A1 - Variateur de vitesse de transmission pour cycles - Google Patents

Variateur de vitesse de transmission pour cycles Download PDF

Info

Publication number
WO2003078240A1
WO2003078240A1 PCT/IT2002/000176 IT0200176W WO03078240A1 WO 2003078240 A1 WO2003078240 A1 WO 2003078240A1 IT 0200176 W IT0200176 W IT 0200176W WO 03078240 A1 WO03078240 A1 WO 03078240A1
Authority
WO
WIPO (PCT)
Prior art keywords
gear
previous
designed
plate
radial
Prior art date
Application number
PCT/IT2002/000176
Other languages
English (en)
Inventor
Alessandro Bello
Alberto Zurlo
Original Assignee
Progetto Bike S.R.L.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Progetto Bike S.R.L. filed Critical Progetto Bike S.R.L.
Priority to PCT/IT2002/000176 priority Critical patent/WO2003078240A1/fr
Priority to AU2002253516A priority patent/AU2002253516A1/en
Publication of WO2003078240A1 publication Critical patent/WO2003078240A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
    • B62M9/00—Transmissions characterised by use of an endless chain, belt, or the like
    • B62M9/04—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio
    • B62M9/06—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like
    • B62M9/08—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like involving eccentrically- mounted or elliptically-shaped driving or driven wheel; with expansible driving or driven wheel

Definitions

  • TECHNICAL FIELD This invention refers to a high efficiency continuous speedgear for cycles.
  • this invention refers to a stepless speed gear which can be operated manually and /or by means of transducers designed to detect variations in the mechanical moment of resistance.
  • This invention finds an application in the field of mechanical industry with reference to the production of bicycles with fixed gears, for example in the field of bicycles for amateurs and professionals.
  • the gears usually consist of means of transverse drive, for the chain of the bicycle in question, easily controlled by the user by means of connecting devices consisting of tensioned wires terminating in appropriate cams designed for the movement of mechanical devices which intervene on the chain.
  • the change in drive ratio is obtained by transferring the chai from one pinion to another by means of a device known as a derailleur.
  • the choice of ratio takes place at the front by means of an overgear generally consisting of two or three crown gears and at the rear by a sprocket wheel consisting of a maximum of nine pinions with an increasing number of teeth.
  • a further disadvantage is represented by the fact that in current gear systems the choice of certain ratios positions the chain out of line with respect to the wheel hubs, with consequent incomplete use of torque at the pedal and the possibility of an unwanted ratio change at the rear hub due to a sudden chain jump when the pedal stroke is reversed. This anomalous positioning of the chain also causes noise and wear of the links and teeth involved in the coupling at that time.
  • This invention aims to provide a high efficiency stepless speed gear for cycles which is capable of overcoming the drawbacks and disadvantages typical of gear systems constructed according to the current art, proposing a product which is simple to apply and easy to produce on industrial scale.
  • This invention also proposes to provide a high efficiency stepless speed gear which can be installed on any bicycle currently on the market. This is achieved by means of a high efficiency stepless speed gear for cycles with the features described in the main claim.
  • the high efficiency stepless speed gear for cycles comprises a central support designed to hold a plate equipped with radial elements, branching out from the support towards the edge of the plate and designed to support and guide respective carriages eqt ⁇ pped with rotating elements coplanar to a plane substantially parallel to the plate, the carriages being simultaneously and concordantly moved by an appropriate kinematism which can be activated by a user.
  • each carriage on the respective radial element moves the rotating elements, in operation supporting a flexible means of transmission, from a position close to the central support to a position adjacent to the edges of the plate and vice versa, in order to continuously vary the drive ratio between the hub and the driving wheel of the bicycle.
  • the rotating elements consist of pinions engaged on a chain designed as a flexible means of transmission.
  • the central portion of the central support housed on the hub of the bicycle driving wheel, is hollow and is designed to house bushings integral with transmission flanges projecting outwards from the plate on the opposite side with respect to the pinions.
  • the transmission flanges can rotate around the wheel pin, being activated by the user by means of an appropriate mechanical drive device terminating with special cams striking against the flanges.
  • the radial elements supporting the carriages consist of threaded bars, hinged to the plate, each presenting a respective bevel gear engaging with at least one bevel ring gear rotated by the bushings.
  • each radial element comprises an elastic means of loading designed to counter the traverse of the carriages presenting the respective pinions engaged with the chain; the energy stored by the elastic loading means is thus subsequently restored when the pinions are no longer in contact with the chain.
  • Each pinion has a shaft housed inside a unidirectional bearing, supported by the respective carriage, designed to guarantee both transmission of the motion and correct autopositioning of the pinion with respect to the chain during the stepless variation in drive ratio.
  • the high efficiency stepless speed gear for bicycles solves the chain jump problem since the chain does not make any lateral movements.
  • the stepless ratio variation is ensured by the continuous movement of the carriages.
  • the controls for the stepless speed gear consist of two manual levers on the handlebars which act on the transmission flanges. This simplification is possible since the rear sprocket wheel consists of a single plate.
  • the high efficiency stepless speed gear for bicycles makes it possible, during gear change ' s on a slope, to exploit all the torque available at the pedal without loss of speed since the chain is always in line with the wheel hubs.
  • This relative positioning of the chain with respect to the wheel hubs does not cause any anomalous wear of the chain links or the pinion teeth involved in the coupling, with consequent limitation of noise.
  • This stepless speed gear for bicycles also offers the possibility of an infinite number of ratios between the minimum limit and the maximum limit of current gear systems.
  • the symmetrical configuration of the gear system allows a balanced distribution of the stresses which in this way do not weigh on the plate and in particular on the pinions which are subjected to considerably reduced wear, increasing the reliability and the life of the gear system.
  • figure 1 represents a cross-section side view of a stepless speed gear for bicycles according to the invention
  • figure 2 shows a front view of the speed gear of figure 1.
  • the reference number 10 indicates in general a stepless gear, in the case in question a high efficiency stepless gear 10 for bicycles comprising a central support 11 designed to hold a plate 12 equipped with a series of radial elements 13, which, according to this embodiment, consist of threaded bars designed to support and guide respective carriages 14 each of which is equipped with a pinion 15 coplanar to a plane substantially parallel to the plate 12.
  • the plate 12 has a central through hole designed to house a internal bushing 17 integral with the drive 19 and an external bushing 20 which also acts as a drive.
  • the internal bushing 17 is fitted on a pin 21 of the bicycle wheel and can rotate around this pin thanks to the presence of rolling bearings 22.
  • the drive flanges 19 and 20 can be activated, to transmit the rotation to the internal bushing 17, by means of eccentrics or cams which are activated, by appropriate controls (not shown in the drawings), by the user.
  • the central support 11 consists of a hollow body, designed to contain a pair of opposed bearings 23a, 23b, which are part of the internal bushing 17; this hollow body has radial openings, corresponding to each respective radial element 13, and is closed at the front by a unidirectional rotation freewheel mechanism 24.
  • the internal bushing 17 is integral with at least one ring bevel gear 25, coaxial to the pin 21, engaging with bevel gears 26a, 26b, presenting axes substantially at right angles to that of the pin 21, and housed in a respective radial opening of the central support 11.
  • each bevel gear 26a, 26b is positioned at the end of a respective radial element or threaded bar 13, but is not directly constrained to it.
  • the bevel gears are integral with the threaded bars 13.
  • the radial elements 13 consist of threaded bars s ipported by bearings 27, integral with the plate 12 and close to its outer edges.
  • Each carriage 14 has a central nut thread housing the threaded bar 13 in such a way that the rotation of the bar causes the traverse of the carriage 14.
  • Each carriage 14 also has a unidirectional bearing 30, in which the respective pinion 15 is housed, designed to guarantee both the transmission of the motion and the correct autopositioning of the pinion 15 with respect to the chain during the stepless variation of the drive ratio.
  • Each pinion 15 can be eqtiipped with a flanged element 31 designed to keep the bicycle chain engaged with the pinion, especially during the traverse of the carriages 14 while the drive ratio changes.
  • the plate 12 also has radial grooves 32 (figure 2) designed to accommodate the base of a respective carriage 14 in order to guide it during its traverse.
  • each threaded bar 13 is equipped internally with a means of elastic loading consisting of a spring 33 which at one end is constrained to a respective bevel gear 26a, 26b, and at the other end to the peripheral end of the threaded bar 13.
  • the spring 33 works by torsion, and when the bevel gears 26a, 26b are rotated, it unloads directly on the end of the threaded bar 13; when the carriage
  • the variation in gear ratio takes place in this case when the pinion connected to a given threaded bar is not coupled with the chain; the variation in ratio consequently takes place in different ways between the various carriages 14, thus obtaining a sequential and smooth ratio variation, without the user having to make an excessive effort in the pedal stroke.
  • the spring 33 is not present, and each threaded bar 13 is constrained to a respective gear 26.
  • the variation in ratio takes place uniformly and simultaneously on all the carriages 14, including those temporarily involved in the coupling force with the chain.
  • the plate 12 can be equipped with a protective guard 34 over the threaded bars 13 and the carriages 14.
  • the high efficiency stepless gear 10 for bicycles according to this invention can present numerous different embodiment variations which are included in the invention concept.
  • each pttlley can support a drive belt, or a "V" belt, or a steel strand enclosed in a rubber sheath.
  • the stepless gear can be positioned on the bicycle hub, or built into the rear wheel, or it can be split between the hub and the rear wheel.
  • the chain is positioned between the wheel and the gear 10; however, another embodiment can foresee the gear
  • the stepless gear according to this invention foresees a first manual solution with levers, positioned for example on the handlebars, connected to tie rods designed to move the cams acting on the drive flanges 19, 20.
  • the following solutions can be foreseen: manual activation but with an electric motor designed to orientate the cams on the drive flanges 19, 20; manual activation with small electric motors, positioned on each carriage 14, designed to receive impulses synchronised with the movement by means of a transmitter integral with the frame of the bicycle.
  • the movement of the carriages 14 takes place when the pinion 15 is not engaged with the chain; automatic activation through the use of a slope transducer, or inclinometer, directly connected to the transmitter described above.
  • each carriage 14 can be equipped with a rolling bearing in order to reduce the friction.
  • the gear 10 according to this invention can be activated by means of the planetary gear of an epicycloidal device positioned on the stepless gear 10 to replace the drive flanges 19, 20.
  • the bevel gear pair (which in the previous embodiment consists of the elements 25, 26 and 16) comprises pinions which engage with only one crown wheel.
  • This crown wheel is activated in both rotation directions with respect to the plate 12, to allow the movement of the carriages 14.
  • the dual rotation of the epicycloidal planetary gear thus takes place with interference or friction locking of the planet wheel or the sun wheel, the sun wheel being integral with the crown wheel, while the planet wheels are idle and hinged on the plate 12.
  • the relative rotation, in both directions, of the sun wheel with respect to the plate 12, is achieved by interference or by acting directly on the sun wheel or on the planet wheel.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Transmission Devices (AREA)

Abstract

L'invention concerne un variateur de vitesse très efficace (10) pour bicyclettes comprenant un support central (11) conçu pour maintenir une plaque (12) équipée d'éléments radiaux (13), partant du support (11) et arrivant jusqu'au bord de la plaque (12), et conçue afin de supporter et de guider des supports mobiles respectifs (14), dotés d'éléments rotatifs (15), situés dans un plan sensiblement parallèle à la plaque (12), les supports mobiles (14) étant simultanément, et de façon concordante, déplacés par une cinématique adéquate pouvant être activée par un utilisateur.
PCT/IT2002/000176 2002-03-20 2002-03-20 Variateur de vitesse de transmission pour cycles WO2003078240A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/IT2002/000176 WO2003078240A1 (fr) 2002-03-20 2002-03-20 Variateur de vitesse de transmission pour cycles
AU2002253516A AU2002253516A1 (en) 2002-03-20 2002-03-20 Stepless variable transmission gear for cycles__________________

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/IT2002/000176 WO2003078240A1 (fr) 2002-03-20 2002-03-20 Variateur de vitesse de transmission pour cycles

Publications (1)

Publication Number Publication Date
WO2003078240A1 true WO2003078240A1 (fr) 2003-09-25

Family

ID=27840301

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IT2002/000176 WO2003078240A1 (fr) 2002-03-20 2002-03-20 Variateur de vitesse de transmission pour cycles

Country Status (2)

Country Link
AU (1) AU2002253516A1 (fr)
WO (1) WO2003078240A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013180397A1 (fr) * 2012-06-01 2013-12-05 Han Hyou Transmission à variation continue pour vélo
CN107128432A (zh) * 2017-06-16 2017-09-05 晋中学院 自行车无级变速器
IT202100012764A1 (it) 2021-05-18 2022-11-18 Stefano Revel Cambio a variazione continua automatica del rapporto per veicoli a due ruote
IT202200004451A1 (it) 2022-03-10 2023-09-10 Stefano Revel Cambio a variazione continua del rapporto per veicoli a due ruote

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4696662A (en) * 1986-08-04 1987-09-29 Gummeringer Henry E Variable-speed drive unit
US4740190A (en) * 1987-01-29 1988-04-26 University Of Florida Variable ratio bicycle chain drive
US5476422A (en) * 1994-09-06 1995-12-19 Schendel; Robert J. Multi-speed transmission for bicycles

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4696662A (en) * 1986-08-04 1987-09-29 Gummeringer Henry E Variable-speed drive unit
US4740190A (en) * 1987-01-29 1988-04-26 University Of Florida Variable ratio bicycle chain drive
US5476422A (en) * 1994-09-06 1995-12-19 Schendel; Robert J. Multi-speed transmission for bicycles

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013180397A1 (fr) * 2012-06-01 2013-12-05 Han Hyou Transmission à variation continue pour vélo
CN107128432A (zh) * 2017-06-16 2017-09-05 晋中学院 自行车无级变速器
IT202100012764A1 (it) 2021-05-18 2022-11-18 Stefano Revel Cambio a variazione continua automatica del rapporto per veicoli a due ruote
IT202200004451A1 (it) 2022-03-10 2023-09-10 Stefano Revel Cambio a variazione continua del rapporto per veicoli a due ruote

Also Published As

Publication number Publication date
AU2002253516A1 (en) 2003-09-29

Similar Documents

Publication Publication Date Title
CN108688771B (zh) 自行车后变速器
US20100210383A1 (en) Actuator
US9855993B2 (en) Variable diameter pulley assembly and continuously variable transmission using the same
KR20010093412A (ko) 무단변속기
CA2677552C (fr) Transmission a variation continue
US11541963B2 (en) Adjustment mechanism and drive
US5048358A (en) Rotary phased radial thrust variable drive transmission
CN1059692A (zh) 变速自行车的自动变扭器传动装置
CN108061136A (zh) 一种无级变速链条传动装置
WO2003078240A1 (fr) Variateur de vitesse de transmission pour cycles
US6779415B2 (en) Mechanical transmission
CN108431457B (zh) 可变速比传动装置
US4154123A (en) Drive for a bicycle
EP1735545A2 (fr) Entrainement pour entrainements (semi-)continus a courroie sans fin
GB2160271A (en) Variable-ratio transmission
KR101172345B1 (ko) 자전거용 무단 변속장치
FR2476256A1 (fr) Roue de transmission a diametre variable
CN201723683U (zh) 一种雪地车无极变速器主动轮
CN108137125B (zh) 自行车传动装置
CN2146611Y (zh) 无级变径传动齿轮装置
US20240149975A1 (en) Sectioned Multiple-Step Pulley Transmission
US20230303211A1 (en) Power transmission
RU2100241C1 (ru) Бесступенчатый вариатор крутящего момента чурикова
US10094452B1 (en) Continuously variable transmission for a bicycle
WO2018178898A1 (fr) Transmission automatique pour bicyclettes

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG US UZ VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP

WWW Wipo information: withdrawn in national office

Country of ref document: JP