EP3172120A1

EP3172120A1 - Bicycle fork, bicycle frame and bicycle

Info

Publication number: EP3172120A1
Application number: EP14730095.8A
Authority: EP
Inventors: Stefan Christ
Original assignee: Bmc Switzerland AG
Current assignee: Bmc Switzerland AG
Priority date: 2014-05-27
Filing date: 2014-05-27
Publication date: 2017-05-31
Also published as: WO2015180756A1

Abstract

A bicycle fork (1) comprises a steering tube (3), designed to be rotatably mounted in a head tube (4) of a bicycle frame. At least some sections of the steering tube (3) in the axial direction have a cross-sectional profile that deviates from a circular form.

Description

Bicycle fork, bicycle frame and bicycle

The present invention relates to a bicycle fork, a bicycle frame and a bicycle according to the independent ones

Claims 1, 10 and 13.

Essential components of a bicycle and their arrangement and connection with each other are known. So is

for example, the handlebar assembly of a bicycle

such that a head tube is attached to the front of the bicycle frame where the down tube and the top tube of the bicycle frame meet.

Respective ends of the down tube and the top tube are, for example, by means of a welded connection

connected with each other and with the top tube.

The control tube is oriented in relation to the bicycle frame in such a way that it is deflected counterclockwise by a predetermined angle from the perpendicular direction in order to give the bicycle a good straight-ahead running performance overall. Substantially at portions of the axial ends of the head tube are two

Rolling, in particular angular contact ball bearings, clamped for pivotal mounting of a fork stem of a bicycle fork in relation to the head tube. By the pairwise arrangement of two angular contact ball bearings in relation to the head tube and

Steerer and corresponding pretensioning of these, e.g. by clamping the revolving tread components of

Angular contact ball bearings by means of a screw-on head nut, the steerer is virtually lossless in relation to the bicycle frame and without wear on rolling elements (For example, rolling balls) of the angular contact ball bearings freely rotatable or steerable. It thus radial forces and also axial forces are absorbed in both directions.

The lower portion of the steerer tube opens into a

Branch of two parallel extending

Fork portions comprising at their distal ends respective receiving portions (e.g., eyes or grooves) for receiving the hub of a front wheel. The upper portion of the steerer protrudes slightly beyond the upper end of the steerer tube. In the steerer tube a stem of a stem is inserted by a handlebar. Of the

Luffing shaft is axial in relation to the steerer tube

movable, whereby the height of the handlebar can be set user-defined. The Vorbauschaft and the

Steerer can be connected in a torsionally rigid manner by means of an elongated tensioning screw which extends in the center-axial direction of the extension shaft and which is screwed with its distal external thread into an internal thread of an expansion cone. The clamping screw is mounted with its screw head in an abutment in the Vorbauschaft (recess). By screwing the clamping screw of the expansion cone is guided axially upwards and thereby spreads distal

End portions of the Vorbauschafts, which in turn come with inner peripheral portions of the steerer in fixed contact. The stem is thus frictionally connected to the steerer tube. Thus, the steering movement or the steering pulse, initiated at the two ends of the handlebar, transmitted lossless to the front wheel. For example, one or more sensors may be mounted in a portion in the region of the front hub at the distal end of at least one of the fork sections. These sensors include, for example, a sensor for detecting the rotational speed of the front wheel (rotational speed sensor). As another example, a sensor may be provided which

Measurements on a front brake (for example

Disc brake or drum brake) absorbs (brake sensor).

The measuring signals of these sensors are fed directly or indirectly via electrical cables to a controller. This control can be used, for example, in the case of

Electric bicycle (e-bike or pedelec) mounted on the handlebar. The controller may be an input unit and a

Output unit, such as a separate keyboard and a separate display device (display). The controller may alternatively comprise a touch-sensitive touchpad as a combined input / output unit. Furthermore, mechanical cables are included, which are guided on brakes for decelerating the front wheel and / or rear wheel. Mechanical cables may also be provided which lead to a gearshift (e.g., chain derailleur or hub gear). These cables can be guided in a sheath (Bowden cable). The wording "cable" here electrical, mechanical

and / or hydraulic lines and their equivalents.

The aforementioned cables can each outside of the bicycle fork and on the outer portion of the head tube

held and guided to the control on the handlebars. For this purpose, the cables must have sufficient length at least at the junction between the bicycle fork and the head tube, so that the cables will not break off when steering. This example of electrical connection

between the at least one sensor and the controller, as well as another example of a mechanical connection between a wheel brake (front wheel or rear wheel) and a brake lever on the handlebar and / or between a

Gear shift and a gear lever on the handlebar, are less preferred,. because the cables are exposed and thus can be easily damaged. In addition, the cables at

Tear off the steering. Furthermore, this example is given no priority for optical reasons.

In another example, the cables are more or less directly at the attachment portion of the respective

Sensors in the region of the front hub via a introduced in the respective fork section bore into the interior of the bicycle fork and guided therein. Here, the bicycle fork is partially hollowed out inside. Such a hollowing of the bicycle fork is _. known in the art and also provides weight savings. The aforementioned cable guide continues to run over the branch portion of the two fork sections in

Direction to the steerer tube and then runs in the interior of the steerer tube along a likewise hollowed axial center portion of the steerer tube. At a position of the projecting over the head tube portion of the steerer tube is again introduced a bore through which

through the cables are led to the outside. From there The cables then run to the control mounted on the handlebar or another electrical evaluation unit.

In this cable guide known in the prior art, the cables are against the outside over long distances

protected, thereby avoiding cable breakage. In addition, the aforementioned risk of separation of the cables is eliminated by a steering movement, since the cable in the range of a single reference space, namely the bicycle fork itself, run. In addition, the cables are not visible from outside, which has aesthetic benefits. Another advantage is that the cables now need not be fastened by fasteners, such as cable ties, cable clips, etc., whereby the

Assembly time is reduced.

A disadvantage of this solution from the prior art, however, is that, in the axial direction of the

Steering considered, the position for insertion of the bore or cable gland at the upper portion of the steerer tube must be selected depending on the position of the upper bearing. The position of the upper rolling bearing is dependent on the length of the control tube, which in turn depends on the size of the bicycle frame. Thus, with one and the same type of bicycle fork, this cable feedthrough nevertheless has to be dependent on different control tube lengths (and thus depending on

different bicycle frame sizes) to each

different positions in the axial direction

to be provided. This has the disadvantage that for several sets of bicycle frames with different Bicycle frame sizes a respective number of appropriately prepared bicycle forks must be prepared (by attaching the cable gland to appropriate

Position) and must be stored. A disadvantage is high production costs and high costs

Storage holder.

The object of the present invention is in the

Provision of a bicycle fork, a bicycle frame and a bicycle, in which the aforementioned problems are solved.

According to the invention, the bicycle fork comprises a

Steerer, which for rotatable storage in one

Head tube of a bicycle frame is formed- _? - Wherein the steerer at least partially along the

Axial direction deviating from the circular shape

Has cross-sectional profile. This is a

Bicycle fork provided, which includes a steerer, along the sections, at least one cable can be guided so that it is guided within a surrounded by the head tube area up from the head tube. So that the cable can protrude beyond the head tube, a cross-sectional profile deviating from the circular shape of the fork stem is created. An essential advantage of this bicycle fork is that the position of a cable feedthrough for passing the at least one cable out of the interior of the bicycle fork can now be arranged in a region of the steerer tube surrounded by the head tube, or in one by the two Rolling bearing restricted area of the steerer tube

can be arranged.

As a result, this cable entry is always like this

positioned within that by the two

Rolling bearing defined portion is positioned, and indeed completely independent of the respective bicycle frame size and thereby differently sized length of the head tube. Thus, all bicycle forks, regardless of the later associated bicycle frame size, be provided at one and the same position with the cable gland. This is in contrast to the prior art, in which the position of the cable gland in dependence of the later associated bicycle frame. must be chosen.

The cables mentioned can be electrical cables for establishing a connection between a sensor and a display or control unit. Furthermore, mechanical cables are included, which are guided on mechanical brakes on the front wheel and / or rear wheel. In the case of hydraulic brakes, the cables are considered hydraulic lines. Mechanical cables may also be included which lead to gear shifts (e.g., chain derailleur or hub gear). The wording "cable" thus means all electrical, mechanical and / or hydraulic cables or conduits and their equivalents.

Preferably, the cross-sectional profile has an in

Axial direction of the fork shaft extended recess. Thus, the recess extends along a

Section of the steerer tube inside the steerer tube and a portion over the upper roller bearing, so that the at least one cable can be passed without hindrance through the upper roller bearing and out of the head tube in the direction of the handlebar.

Preferably, the recess forms a clearance, which between the steerer tube and a virtual

Line showing the circular shape of the steerer

completed, is defined. This allows the

Recess quickly and easily, e.g. are formed by face milling, along a peripheral portion of the steerer and in axial extension of the steerer tube. By this milling a clearance in the geometric shape of a circular segment is created between the steerer tube and the inner surface of the inner ring of the rolling bearing, through which the at least one cable can be easily performed. Again, it shows up as special

advantageous that this milling out in all bicycle forks uniformly, i. at the same depth and at the same

Extension, can be performed, regardless of which bicycle frame size later the bicycle fork is assigned.

Preferably, the surface of the clearance is determined so that at least one cable in the axial direction of the steerer tube is feasible. As a result, the at least one cable can easily be led out of the head tube.

Preferably, the recess is formed in the cross-sectional profile as a circle segment. Through the education of

Recess in the geometric shape of a circle segment, for example, two cables next to each other and in tight system along the milled section of the steerer be performed clean, without these will cross over.

Preferably, the recess is formed as a cutout extending in the axial direction of the steerer tube. Here, for milling the recess, for example, the steerer and a milling tool, starting at one

Section of the steerer, which is arranged in the assembled state within the head tube,

approached each other. Starting from this position, the steerer tube becomes the same depth in the axial direction

milled. This milling work can be performed up to the upper end of the steerer, i. up to that

Section of the steerer, at which later on

Assembly of the handlebars is attached. Alternatively, the cutout does not reach the upper end of the steerer tube. However, it is important that the cutout be made at least in overlap with that portion of the steerer tube at which the steerer tube engages the inner ring of the upper rolling bearing.

Preferably, the recess is formed as a groove extending in the axial direction of the fork shaft. In this embodiment, for example, by means of a

Tip-milling tool a groove registered in the peripheral portion of the steerer tube, wherein the groove in

Axialrichtung thereof extends. The surface of the space formed by the groove, in sectional view of the

Considered steerer, this must be sufficiently large to accommodate the at least one cable. One Advantage of this embodiment is that the at least one cable is guided firmly along the groove. In case of more than one cable, the routed cables can not twist. Another advantage is that no more than necessary material of the steerer tube is removed to still lead the at least one cable. An advantage is also that under this requirement a maximum possible cross-sectional area of the steerer remains, so that the stability of the

Steerer, which is exposed to strong forces, remains ensured.

Preferably, the cross-sectional profile of the steerer is partially formed as a solid profile. In this

Embodiment remains, viewed in sectional view, maximum material, such as steel, aluminum, etc., which at the same time the stability of the steerer is increased. Thus, the steerer can withstand strong forces without breaking.

Preferably, the cross-sectional profile of the steerer is in sections with a in the Mittenaxialrichtung of

Formed forked excavation excavation. One

Advantage of the excavation consists in the weight saving of the bicycle fork. It should be noted that the aforementioned entry of the recess in the form of the

Cutout or groove in the surface area of the

Steerer does not reach so deep that it touches on the

Excavation in the middle axial direction meets.

The above object is also achieved by a

Bicycle frame with a head tube and a rotatable therein mounted bicycle fork solved according to one of claims 1 to 9. An advantage of this bicycle frame is that the bicycle fork can be prepared completely independent of the size of the bicycle frame. It must therefore not differently prepared bicycle forks

be stored. Also, the processing steps for making the bicycle forks are always consistent. This reduces time, manufacturing costs and storage costs.

Preferably, the bicycle frame further comprises at least two rolling bearings, which are each fitted torsionally rigid in the head tube and on the steerer, designed for pivotal mounting of the steerer in relation to the head tube. It is thus created a bicycle frame, in which one or more cables along a freely definable

Section inside the bicycle fork can be performed and these cables can be led out by consistently introduced cable entries from the inside of the bicycle fork.

Preferably, the bicycle frame comprises at least one

Cable, which is guided in sections along the recess. Thus, the at least one cable is not subject to any tensile stress and can not be crushed. The at least one cable may be an electrical cable. Alternatively or additionally, the at least one cable may be an arrangement of a flexible one

Sheath be guided cable. Such an arrangement is also referred to as Bowden cable. This cable or

This cable can be a tensile force to a mechanical Apply brake (drum brake or disc brake) to decelerate the front wheel and / or rear wheel. In the case of a hydraulic brake, the wording "cable" means a hydraulic line for directing pressurization to this hydraulic brake.

Alternatively or additionally, the cable may be a cable, which is guided to a gearshift, for example, at least one Kettenumwerfer or a hub gear.

The above object is also achieved by a bicycle with a bicycle frame according to claim 11 or 12.

Due to the possibility of producing uniform bicycle forks, which are completely independent of the size of the later associated bicycle frame, is

Overall, a bicycle created, which is quick and easy to assemble and is also inexpensive.

Preferably, the bicycle further comprises at least one electrical sensor for receiving a mechanical size of a front wheel and / or rear wheel. By the

Bicycle according to the invention can electrical connections between this at least one sensor and a

electrical control or other electrical device can be made quickly and easily. Furthermore, mechanical connections, for example, between controls on the handlebar of the bicycle and mechanical components, such as a chain derailleur

Gear shift and / or a mechanical or hydraulic brake to be produced. Embodiments of the present invention will be explained in more detail below with reference to figures. Show it:

Figure 1 is a partial schematic representation of a

Bicycle frame according to the invention;

Figures 2a-d are sectional views of the control tube in Figure 1;

and

Figure 3 is a partial schematic representation of a

Bicycle frame according to the prior art.

FIG. 1 shows a schematic partial representation of a

Bicycle frame according to the invention. A bicycle fork 1 comprises fork sections 2 2 ^VX , which open at their upper fork point in a steerer tube 3. The steerer 3 is guided by a cylindrical head tube 4 of the bicycle frame. The control tube 4 is connected at its outer periphery with a top tube 5 and a down tube 6 as structural components of the bicycle frame, for example by welding. At axial ends of the control tube 4 are

Rolling 7 ^λ , in particular angular contact ball bearings, clamped between the head tube 4 and the steerer tube 3. With this arrangement, the bicycle fork 1 can be turned almost without loss and play in relation to the head tube 4 and thus in relation to the bicycle frame or be steered. According to the invention, the steerer 3 is formed at least in sections along the axial direction with a profile shape deviating from the circular shape. One

Surface portion of the steerer 3 is provided with an axially extending recess 8 which extends in sections within a portion surrounded by the head tube 4 upwards. The recess 8 is formed in the embodiment shown in Figure 1 as a planar cutout. As a result, material of the steerer tube 3 in the geometric shape of a

Taken from the circle segment. The recess 8 extends over the upper roller bearing 7 ^{λ λ} away, so between

Steerer 3 and the inner ring of this bearing 7 ^{Λ x} creates a free space.

The bicycle shown in FIG. 1 comprises, for example, one in the region of the hub of the front wheel (not shown)

Speed sensor (not shown) for detecting the speed of the front wheel. The speed sensor converts these

Information into electrical signals around which,

for example, passed over two electrical cables 9, are supplied to a controller. This control is attached to the handlebar, for example, which provides the information of these signals in an indication of the current

Speed at which the bike is driven converts. This information is on a handlebar

displayed speed display.

The bicycle may for example be an electric bicycle. In this example, the controller may provide a drive control for optimal operation of an electric vehicle Driving support motor. Alternatively or additionally, the signals can be fed to a speed indicator also mounted on the handlebar. Alternatively or additionally, additional sensors may be mounted in the region of the hub of the front wheel, whose signals are also supplied via electrical cables 9 to the controller and / or to an assigned display.

The cables 9 are preferably directly on

Attached portion of the respective sensor through a cable gland on one of the lower fork portions 2 2 ^{Λ led} into the interior of the bicycle fork 1 and extend along the respective fork portion up to the steerer 3. The cables 9 are then through a further cable gland, which in a section along the Recess 8 is introduced, led out of the bicycle fork 1. In the assembled state of

Handlebar assembly extend the cable 9 so a piece along this recess 8. To lead out the cable 9 out of the control tube 3 out the cable. 9

advantageously by the trained space between the steerer tube 3 and the inner ring of the upper bearing 7 ^Λ performs. The lead-out portions of the cables 9 are connected to the controller and / or the other display device.

Alternatively or additionally, and as shown in Fig. 1, at least one cable 10 is passed through the down tube 6. This cable 10 may e.g. an electrical cable, which is one on the wheel hub of the rear wheel

attached sensor unit is passed. Further alternatively or in addition, the cable 10 may be a mechanical cable, for example, guided in a sheath and protected (Bowden cable), which is connected to a mechanical

Rear brake, led to at least one Kettenumwerfer a gear shift and / or to a hub gear on the rear wheel. Alternatively or additionally, the cable 10 may comprise a hydraulic line which connects to a

hydraulic rear brake is guided. Likewise, although not shown, the cable 10 may be passed through the top tube 5.

The cables 9, 10 are thereby advantageously provided by portions of the bicycle fork 1 and the bicycle frame, e.g. Top tube 5 and / or down tube 6, protected. A further advantage is that the cable feedthrough introduced into the steerer tube 3 can be introduced into the steerer tube 3, irrespective of the size of a bicycle frame associated with the bicycle fork 1 (and thus independently of the longitudinal extent of the steering tube 4). Thus, a plurality of bicycle forks 1 can be made uniform, which are always complementary to bicycle frames of different sizes.

FIGS. 2 a to d each show cross-sections which are taken perpendicular to the axial direction through the upper rolling bearing 7 ^λλ shown in FIG. It is thus

Cross-sectional profiles shown in a section in which the steerer 3 is engaged by the upper roller bearing 7 ^λ , which in turn firmly in the head tube

is clamped. In FIGS. 2a to d, the upper one is Rolling 7 ^{Λ λ} schematically indicated by its inner ring or by its rotating tread component.

In the sectional view shown in Figure 2a is the

Steerer 3 provided with the recess 8, which as a planar cutout along the axial direction of the

Steerer 3 is formed. By means of this recess 8 formed space two cables 9, 10 are guided and can thus above the head tube

be led out (see Figure 1). The steerer 3 is formed in this embodiment as a solid profile.

As a result, the stability of the steerer tube 3 is increased. The cable 9 in the example shown is an electrical cable 9 which is guided by the bicycle fork (see FIG. 1) to an electrical sensor in the region of the front wheel hub. In the case of the cable 10, the example shown is a mechanical cable 10 or a cable pull which runs in the region of the control tube and is guided from there into the down tube or top tube of the bicycle frame (see FIG. 1). The cable 10 may also be a hydraulic line 10 for a hydraulic brake.

The embodiment shown in Figure 2b differs from the embodiment shown in Figure 2a in that the

Steerer 3 is provided with a along the center axis extending cavity. This cavity may extend along the entire steerer tube 3. By the

gutted material will achieve weight savings.

Figure 2c shows an example in which the recess 8 is formed as a groove which in the axial direction in the steerer tube 3 is registered. The space formed by the groove between the fork shaft 3 and the inner ring of the rolling bearing 7 ^λΛ is sufficient to carry out the two cables 9, 10. As shown in Figure 2c, the electrical cables 9, 10, which by their

Insulation jacket are slightly elastic, are pressed firmly into the groove. As a result, the cables 9, 10 are reliably held along the course of the groove. Thus, the likelihood of damage to the cables 9, 10 is reduced.

Figure 2d shows another example in which the cables 9, 10 are received within a recess as a recess 8 in the material of the steerer tube 3. In the example shown, this recess is partially surrounded or constricted by material portions of the steerer tube 3. In this example, the cables 9, 10 are separated by the constriction in the recess

introduced. Thus introduced are the cables 9, 10 further reliably and firmly held. In addition, the cables 9, 10 are protected against the outside. This will be a

Damage to the cables 9, 10 prevented.

FIG. 3 shows a bicycle frame in a partial view according to the prior art. Here, at least one cable 19 is guided within sections of a bicycle fork 11. By an above an upper roller bearing 17 ^x in a steerer 13 introduced cable gland, the cable 19 out of the bicycle fork 11 out to the outside. A disadvantage is that these

Cable gland at a position on the steerer tube 13 must be introduced, which is dependent on the height or longitudinal extent of a control tube 14. In other words, the position of the grommet is dependent on the size of the intended

Bicycle frame.

Thus, this cable entry must be separately in

Dependence of the respective bicycle frame size are registered in the bicycle fork 1. Due to this separate processing of the respective bicycle forks 11 arise, high costs. In addition, for example, accordingly

differently processed bicycle forks 11 according to the size of a later intended bicycle frame

be stored, resulting in high storage costs

caused.

Claims

claims

1. bicycle fork (1) with a steerer tube (3),

formed for rotatable mounting in a control tube (4) of a bicycle frame, wherein the steerer tube (3) at least in sections along the axial direction has a deviating from the circular cross-sectional profile.

2. bicycle fork (1) according to claim 1, wherein the

Cross-sectional profile one in the axial direction of the

Steerer (3) has extended recess (8).

3. bicycle fork (1) according to claim 2, wherein the

Recess (8) forms a free space which is defined between the steerer tube (3) and a virtual line which completes the circular shape of the steerer tube (3).

4. bicycle fork (1) according to claim 3, wherein the

Surface of the free space is determined such that at least one cable (9, 10) in the axial direction of the steerer tube (3) is feasible.

5. bicycle fork according to one of claims 2 to 4, at

which the recess (8) is formed in the cross-sectional profile as a circle segment.

6. bicycle fork (1) according to one of claims 2 to 5, wherein the recess (8) is formed as a in the axial direction of the steerer tube (3) extending cutout.

7. bicycle fork (1) according to one of claims 2 to 5, wherein the recess (8) is formed as a in the axial direction of the fork shaft (3) extending groove.

8. bicycle fork (1) according to one of the preceding claims, in which the cross-sectional profile of the steerer tube (3) is formed in sections as a solid profile.

9. bicycle fork (1) according to one of the preceding claims, wherein the cross-sectional profile of the steerer tube (3) in sections with a center-axial direction of the steerer tube (3) extending cavity

is trained.

10. bicycle frame with a head tube (4) and a

Rotationally mounted bicycle fork (1) according to one of the preceding claims.

11. The bicycle frame according to claim 10, further comprising

at least two roller bearings (7 7 ^λ ), which in each case in the control tube (4) and on the steerer tube (3) are rotationally rigid fitted for the pivotal mounting of the steerer tube (3) in relation to the control tube (4).

12. bicycle frame according to claim 10 or 11, further

comprising at least one cable (9, 10) which is guided in sections along the recess (8).

13. A bicycle with a bicycle frame according to claim 11 or 12.

14. A bicycle according to claim 13, further comprising at least one electrical sensor for receiving a mechanical size of a front wheel and / or rear wheel.