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
  • B62M3/00—Construction of cranks operated by hand or foot
• • 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
  • B62M3/00—Construction of cranks operated by hand or foot
  • B62M3/003—Combination of crank axles and bearings housed in the bottom bracket

Definitions

• This invention relates to a hub for bicycles, particularly to a front hub.
• the known front hubs have a tube, i.e. a tubular body, at the extremities of which are mounted the pedal cranks for the setting in motion of the vehicle.
• a tube i.e. a tubular body
• the pedal cranks for the setting in motion of the vehicle.
• On the tube one or more sprocket wheels are also keyed forming part of the vehicle transmission system.
• the latter is usually composed of a group of front sprocket wheels, associated with the pedal cranks, and a group of rear sprocket wheels, integral with the rear wheel.
• the two groups are connected by means of a chain which, operated by the rotation of the front sprocket wheels, drags the rear sprocket wheels in motion, and therefore the rear wheel of the vehicle.
• the tube is installed on the bicycle frame by means of one or more bearings that may be of various types such as, e.g., ball bearings, sliding bearings, etc..
• the bearings allow the tube itself to rotate around a fixed axis with respect to the bicycle frame.
• the known front hubs have several drawbacks.
• a first drawback is linked to the pedal cranks.
• Pedal cranks are known made of a solid material, very durable, but heavy. Pedal cranks are also known with a lightened, partially hollow structure, lightweight but little resistant.
• a third drawback of known hubs is linked to the fact that, to obviate the drawbacks described above, front hubs are often used, with elements associated with them, specifically designed according to the model of bicycle on which they are to be installed.
• the main aim of this invention is to provide a lightweight hub for bicycles and, at the same time, resistant to the stresses acting on the pedal cranks during pedaling.
• one object of this invention is to provide a hub for bicycles which is easy and fast to install and adjust.
• One object of this invention is to provide a hub for bicycles that allows ensuring the stability and holding of the various elements associated therewith.
• a further object of this invention is to provide a hub for bicycles usable in a flexible manner on different models of bicycles.
• Another object of this invention is to provide a hub for bicycles which allows overcoming the mentioned drawbacks of the prior art within the ambit of a simple, rational, easy, effective to use and affordable solution.
• Figures 1 and 2 are axonometric views of the hub according to the invention.
• Figure 3 is a sectional view of the hub according to the invention.
• Figure 4 is a sectional view of a detail of the hub according to the invention.
• Figures 5 and 6 are axonometric views of details of the hub according to the invention.
• Figure 7 is an axonometric exploded view of the hub according to the invention.
• reference number 1 globally indicates a hub for bicycles, particularly a front hub.
• the hub 1 comprises at least one rotation shaft 2 installable on a frame of a bicycle, for simplicity not shown in the figures.
• the shaft 2 e.g. is composed of a tube, as illustrated in the figures.
• the tube 2 is fitted in a tubular casing 3 forming part of the bicycle frame.
• a group of bearings 4 adapted to allow the rotation of the tube itself around an axis 5 of rotation.
• the bearings 4 are positioned between the inner surface of the tubular casing 3 and the outer surface of the tube 2 and are of the type of ball bearings.
• the hub 1 also comprises a first pedal crank 6 and a second pedal crank 7 useful for the setting the bicycle in motion.
• the pedal cranks 6, 7 comprise an inner reticular structure 34.
• the inner structure 34 comprises two running elements 36 and a plurality of diagonal elements 37 bound to one another and to the running elements 36 so as to define triangular cavities 38 in the inner structure itself.
• the inner structure 34 in fact, is a reticular structure made with a single row of running elements 36 and diagonal elements 37 coplanar to one another and defining a reticular structure.
• the reticular structure extends between two side boards 39a, 39b arranged in the proximity of the extremities of the pedal cranks 6, 7.
• the triangular cavities 38 with the exception of the end cavities, i.e. of the cavities arranged in the proximity of the side boards 39a, 39b, are of the type of isosceles triangles.
• the triangular cavities 38 therefore, have substantially equal inclination angles so as to allow the even distribution of the efforts induced by the flexural stresses to which the pedal crank 6 or the pedal crank 7 is subjected.
• the inner structure 34 is made of "Ergal", an aluminum alloy 7075 having high mechanical resistance.
• the pedal cranks 6, 7 comprise an outer casing 35 enveloping at least partially the inner structure 34.
• the outer casing 35 in fact, envelops the inner structure 34 such as a stocking, covering it.
• the casing 35 entirely covers the inner structure 34, from the side board 39a to the side board 39b.
• the casing 35 is made of a composite material of carbon fiber. This way, in addition to ensuring high mechanical resistance, resulting from the intrinsic properties of the material, top lightness is also ensured.
• a pedal crank having the inner structure 34 and the outer casing 35 previously described thus, has greater resistance to torsional and flexural efforts with respect to a pedal crank made of a solid structure and having the same weight.
• the pedal cranks 6, 7 illustrated in the figures are much lighter than a similar pedal crank made of a solid structure.
• the pedal cranks 6, 7 have positioning seats 8 shaped so as to be associated with the extremities of the tube 2 to achieve a pack assembly of the pedal cranks themselves with the tubular casing 3 and with a sprocket wheel 9 forming part of the bicycle transmission system.
• the tube 2 is made of a composite material of carbon fiber, but other materials cannot be ruled out.
• the tube 2 has a first end portion 10 comprising at least a first positioning element 11, adapted to facilitate, precisely, the positioning of a first pedal crank 6.
• the tube 2 also has a second end portion 12, opposite to the first end portion 10 and having at least a second positioning element 13, adapted to facilitate the positioning of a second pedal crank 7.
• the tube 2 is tubular with the first end portion 10 which has two first positioning elements 11 and with the second end portion 12 which has five second positioning elements 13.
• the positioning elements 11, 13 are extensions of the tube 2, that is, they follow the shape of the tube 2 forming a toothing which forms a crown on the relative end portion 10, 12 with which they are associated.
• the first positioning elements 11 are formed at diametrically opposite positions.
• the first positioning elements 11 are adapted to couple to respective cavities formed on the first pedal crank 6 at the respective positioning seat 8 and so as to allow the correct angular positioning of the same.
• the solution cannot also be ruled out in which the first positioning elements 11 are in a number different to two.
• the first end portion 10 has an inner flared surface 14 in the shape of a cone narrowing from the inside to the outside of the tube 2.
• the inner section of the tube 2 narrows from the inside of the tube itself towards the outside.
• the hub 1 comprises a first positioning system 15, 18 at least partly fitted in the tube 2 and adapted to lock the first pedal crank 6 in a predefined position.
• the first system 15, 18 comprises a coupling element 15 with a through hole 17 and having an outer surface 16 substantially flared, adapted to be coupled to the inner surface 14 of the first end portion 10 so as to define a cone-on-cone coupling.
• the coupling element 15 is of the type of a pin insertable within the tube 2 from the second end portion 12.
• the pin 15 is of a size such as to make a cone-on-cone coupling with the inner flared surface of the first end portion 10 of the tube.
• the pin 15 is also made of a solid body, that is, has a continuous outer edge and fully engaged on the inner surface 14.
• the pin 15 is star-shaped, that is, with a toothed edge adapted to be coupled to the aforementioned inner surface.
• the first system 15, 18 also comprises a first locking element 18 having a first insertion body 19 engageable in the through hole 17 of the coupling element 15 and a first locking head 20 associated with the first insertion body 19 and adapted to abut against the first pedal crank 6.
• the first locking head 20 abuts against the first pedal crank 6 thus preventing the first locking element 18 to move forward inside the tube 2.
• the through hole 17 is internally threaded and the first insertion body 19 is externally threaded so as to form with the hole itself a screw-nut screw coupling.
• the screwing of the first locking element 18 allows the locking in position of the first pedal crank 6, a compressive force being exerted on it by the locking head 20 which brings the pedal crank itself closer to the first end portion 10.
• the first insertion body 19, moreover, comprises a threaded connecting seat 21, formed at the opposite position to the first locking head 20 and adapted to interact with a second positioning system 22, 23.
• the hub 1 comprises a second positioning system 22, 23, at least partly inserted inside the tube 2, adapted to lock the second pedal crank 7 in a predefined angular position.
• the second positioning system 22, 23 is associable with the first positioning system 15, 18 for the arrangement of the second pedal crank 7 in a longitudinal position adjustable along the axis of rotation, which coincides with the axis of the tube 2.
• the second positioning system 22, 23 comprises a second locking element 22 prismatically insertable in the second end portion 12 so as to define a prismatic coupling with the second pedal crank 7 for locking the latter in the aforementioned predefined angular position.
• the second positioning system also comprises a connecting element 23 inserted in the tube 2 and associated with the connecting seat 21.
• the second end portion 12 of the tube 2 is inserted inside the positioning seat 8 of the second pedal crank 7 with the second positioning elements 13 which protrude at least partially from the pedal crank itself.
• the second locking element 22 has a second insertion body 24 and a second locking head 25.
• the second insertion body 24, similar to the first insertion body 19, is inserted to measure into the tube 2 through the second positioning seat 8.
• the second locking head 25 is adapted to abut against the second pedal crank 7.
• the second locking head 25 comprises positioning tabs 26, equal in number to the number of the positioning elements 13, and which extend in a radial manner on the lying plane of the head itself.
• the positioning tabs 26 define a toothed profile which, when the head is in abutment against the pedal crank, is coupled to the positioning elements 13.
• the second positioning elements 13 position themselves in the spaces left between one tab and the other, thus ensuring the prismatic coupling between the second locking element 22 and the second pedal crank 7.
• At least one locator element 27 is formed adapted to facilitate the identification of the correct angular position of the pedal crank itself.
• the locator element 27, aligned with a preselected second positioning element 13a, univocally identifies the angular position of the second pedal crank 7.
• the geometric arrangement of the locator element 27 and of the first and second positioning elements 11, 13 is such that, once the angular position of the first pedal crank 6 is defined, the position is also defined of the second positioning element 13 and, therefore, through the locator element 27, also the angular position of the second pedal crank 7.
• the locator element 27 is formed in a different position, or is shaped differently, provided that it allows positioning the two pedal cranks 6, 7 rotated by 180° relative to one another.
• the second locking element 22 has a recessed seat 28 communicating with a recessed channel 29 crossed by the connecting element 23.
• the recessed seat 28 is substantially cylindrical.
• the connecting element 23 is of the type of a threaded screw adapted to form a screw-nut screw coupling with the connecting seat 21.
• the threaded screw 23 has a threaded elongated body 23 a and a cylindrical head 23b.
• the elongated body 23a crosses longitudinally the second locking element 22 and the tube 2 and is screwed onto the connecting seat 21 of the first locking element 18.
• the cylindrical head 23b takes a recessed position on the second locking element 22, in particular in the recessed seat 28.
• the conformation of the cylindrical head 23b and of the recessed seat 28 allows the connecting element 23 to rotate also with the cylindrical head 23b positioned in the recess, there being no prismatic coupling between the two.
• interposition elements 40 adapted to ensure the contact between the elements interposed between the two pedal cranks when the distance between the two (q- factor) is greater than the length of the tube itself.
• the hub 1 comprises locking means 30 of the second pedal crank 7 in the aforementioned longitudinal position.
• the locking means 30 comprise a pair of gripping elements 31 formed on the pedal crank and enveloping the tube 2.
• the gripping elements 31 are extensions of the second pedal crank 7 that, in the proximity of the positioning seat 8, envelop the positioning seat 8 itself.
• the gripping elements 31 are associated with a tightening element for simplicity not shown in the figures, adapted to mutually approach the gripping elements themselves so as to grip the second end portion 12 housed in the positioning seat and, therefore, to allow the fixing of the longitudinal position of the second pedal crank 7 and the aforementioned shrink-fit friction.
• each gripping element 31 comprises a median pin 32 having a passage 33 intended to let the tightening element pass through.
• each median pin 32 is substantially aligned to allow the insertion of the tightening element.
• the tightening element can be of the type of an Allen screw, but alternative solutions cannot be ruled out.
• the first positioning system 15, 18 allows the mounting of the first pedal crank 6 on the tube 2.
• the first end portion of the tube 2 is associated with the positioning seat 8 of the first pedal crank 6 through the insertion of the positioning elements 11, 13 in the seat itself.
• the first pedal crank 6, this way, is positioned in a predefined angular position.
• the locking of the first pedal crank 6 in such a position is achieved through the cone-on-cone coupling of the coupling element 15 and through the screwing of the first locking element 18 in the coupling element itself.
• the second positioning system 22, 23, allows the mounting of the second pedal crank 7 on the second end portion 12 of the tube 2.
• the angular position of the second pedal crank with respect to the axis 5 of the tube 2 is determined by the alignment of the second positioning element 13a with the locator element 27.
• the locking of the second pedal crank 7 in the aforementioned angular position is made by means of the insertion of the second locking element 22.
• the particular shape of the second insertion body 24 and, especially, of the second locking head 25, ensures the prismatic coupling between the pedal crank itself and the tube 2, thus preventing relative rotations between the two.
• the connecting element 23 allows the adjustment of the longitudinal position of the second pedal crank 7, in addition to ensuring the holding of the hub 1 and of the other elements associated with it in a pack.
• the elongated body 23a in fact, being screwed to the connecting seat 21 of the first locking element 18, transmits a longitudinal force along the elongated body itself which tends to bring the second pedal crank 7 closer to the first pedal crank 6.
• the coupling between the second locking head 25 and the positioning seat 8 of the second pedal crank 7 allows the connecting element to rotate and, therefore, to be screwed or unscrewed for the adjustment of the longitudinal position of the pedal crank itself.
• This way, the elements interposed between the two pedal cranks (tubular casing 3, bearings 4, sprocket wheel 9) are compressed and, consequently, their stability is facilitated.
• the longitudinal position of the second pedal crank 7 is fixed through the locking means 30.
• the pedal cranks described above in fact, optimize the ratio between resistance and lightness thanks to the combination of the inner reticular structure, which is light and flexural resistant at the same time, and the carbon fiber casing, which is light and also torsion resistant.
• the hub devised is also quick and easy to install and adjust.
• the various components of the hub are easy and user-friendly to assemble.
• the adjustment of the positions of the pedal cranks is particularly simple.
• the first and the second positioning system in fact, comprise components and elements particularly easy to assemble.
• the coupling element is inserted in an user- friendly manner in the tube, as well as the first locking element is easily inserted into the positioning seat.
• the devised hub also ensures high stability and high holding of the various elements associated therewith, both thanks to the effect of the shrink- fit friction, and to the screwing of the various elements, in particular of the second connecting element.
• the action of the second connecting element in fact, facilitates the holding of the pack assembly of the pedal cranks and of the components interposed between them.
• the through hole of the coupling element facilitates such action, thus increasing the surface area available for the screw-nut screw coupling between the threaded element and the connecting element.
• the devised hub for bicycles can be used with flexibility on different models of bicycles, since it does not have any particular characteristics of a bicycle model rather than another, but has characteristics adaptable to any model, in particular thanks to the possibility of the longitudinal adjustment of the second pedal crank.
• the hub described in fact, does not have a fixed "q-factor" but allows an adjustment of such a parameter thanks to the longitudinal positioning of the second pedal crank and thanks to the use of interposition elements.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Steering Devices For Bicycles And Motorcycles (AREA)
• Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
• Turning (AREA)
• Arrangement Or Mounting Of Propulsion Units For Vehicles (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=55410046

Family Applications (1)

Country Status (3)

Family Cites Families (9)

• 2015
  • 2015-11-05 IT ITUB2015A005121A patent/ITUB20155121A1/it unknown
• 2016
  • 2016-11-04 EP EP16816740.1A patent/EP3371042A1/de not_active Withdrawn
  • 2016-11-04 WO PCT/IB2016/056636 patent/WO2017077487A1/en active Application Filing

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