Bicycle frame with center stand connection

Abstract

A bicycle frame is presented, comprising a bottom bracket shell and connecting means designed to connect a bicycle stand to or near the bottom bracket shell. First connecting means are oriented horizontally and are designed to receive fastening means by which the bicycle stand is attached to the bicycle frame. Second connecting means are designed to receive the bicycle stand in a form-fitting manner and have a cross-section deviating from circular, such that they ensure that the bicycle stand is non-rotatably engaged with the second connecting means. Furthermore, the invention relates to a bicycle stand and the use of a bicycle stand as a central stand.

Description

[0001] The invention relates to a bicycle frame.

[0002] For the sake of simplicity, the term “motor” is used below, whereby this always refers only to the motor that serves as the drive for driving the bicycle, regardless of whether the bicycle may have other motors, such as servo motors in an electrically controlled derailleur or the like.

[0003] Bicycle frames designed for the installation of a motor, specifically a mid-mounted motor, feature a motor mount. The bottom bracket, which every motorized bicycle also has, is housed within the motor-gearbox unit in these bicycle frames, forming the bottom bracket shell, while the bicycle frame itself lacks a bottom bracket shell.

[0004] In contrast to the aforementioned bicycle frames, the invention relates to a bicycle frame that is not designed for the installation of a traction drive motor and therefore does not have a motor mount, but rather a bottom bracket housing. Such bicycle frames can be used to manufacture a motorless bicycle or to manufacture a motorized bicycle if the motor is not arranged as a mid-mounted motor, but rather, for example, as a hub motor in one of the bicycle's wheels.

[0005] DE 20 2022 101 272 U1 discloses a bicycle frame and a matching bicycle stand. The bicycle frame is equipped with a connection for a center stand and has a motor mount. Since the motor-gearbox unit typically requires much more space than a bottom bracket shell, the distance between the motor mount, which is designed to accommodate the motor-gearbox unit, and the rear wheel is considerably smaller than in a bicycle frame that merely has a bottom bracket shell that is significantly smaller than the motor mount and can also be referred to as a "motorless" bicycle frame.

[0006] The space problems regarding the available installation space, as described in DE 20 2022 101 272 U1, do not usually exist with motorless bicycle frames.

[0007] Older designs of these motorless bicycle frames typically involve bicycle frames made of tubular steel. They have a crossbar between the two horizontal chainstays of the bicycle frame at a distance behind the bottom bracket shell, creating an approximately rectangular opening defined by the bottom bracket shell, the two chainstays, and the crossbar. A bicycle stand having a stand head and a support with at least one leg that is pivotally mounted relative to the stand head can be attached to such a motorless bicycle frame between the two wheels; this is referred to as a center stand or mid-structure stand. For this purpose, a so-called stand plate is placed over the chainstays and the crossbar over the aforementioned rectangular opening. The stand head is placed against the chainstays and the crossbar from below and screwed to the stand plate.

[0008] More recent designs of motorless bicycle frames have been developed with other materials used for the bicycle frame in mind, such as aluminum or fiber composites, especially carbon fiber. The considerable clamping forces acting between the kickstand head and the kickstand plate on the frame elements clamped between them can lead to damage to the bicycle frame if the permissible tightening torques for the screws are exceeded. This development has therefore led to the installation of bicycle kickstands close to the rear wheel axle, namely in the area of ​​the rear ends of the chainstays or the rear dropouts of the bicycle frame. As a result of this development, the aforementioned cross member between the chainstays has been omitted from many bicycle frames for cost-effective reasons.

[0009] The invention is based on the object of providing a bicycle frame with a bottom bracket that allows the installation of a center stand while protecting the frame tubes as much as possible. Furthermore, the invention is based on the object of providing a suitable bicycle stand.

[0010] This object is achieved by a bicycle frame having the features of claim 1 and by a bicycle stand according to claim 10 and by the use of a bicycle stand according to claim 14.

[0011] In other words, the invention proposes the use of a connection geometry between the bicycle frame and the bicycle stand as is generally known from DE 20 2022 101 272 U1. This is surprising insofar as the problem of available installation space, which is the basis of DE 20 2022 101 272 U1, does not generally exist in bicycle frames equipped with a bottom bracket shell. In addition, a bicycle frame provided according to the invention and equipped with a bottom bracket does not have the motor mount, which according to DE 20 2022 101 272 U1 is provided with the corresponding connection means for mounting the bicycle stand. Rather, according to the invention, the bicycle frame is provided with the connection means either on the bottom bracket shell itself or nearby, e.g.These can be provided on the seat tube of the bicycle frame, which extends upwards from the bottom bracket shell and is intended at its upper end to hold the bicycle saddle, for example to accommodate a seat post.

[0012] The bottom bracket shell is designed to absorb high forces: for example, when the cyclist climbs out of the saddle and pedals out of the saddle, high bending forces act on the bottom bracket and must be absorbed by the frame tubes adjacent to the bottom bracket. This structural stability of the bicycle frame in the area of ​​the bottom bracket allows for the integration of frame-side attachment devices, allowing a bike stand to be attached to it without overloading the frame tubes.

[0013] The connection means can therefore be attached directly to the bottom bracket shell, which is typically made of metal, e.g., by manufacturing it as a cast part with a corresponding geometry that includes the connection means, or by attaching the connection means to a bottom bracket shell consisting of a tubular section, e.g., by soldering it. The first and second connection means can be combined into a common component, ensuring precise alignment of both the first and second connection means relative to one another and, moreover, keeping the number of components to be handled as low as possible.

[0014] Alternatively, the connection surfaces can be located near the bottom bracket shell rather than on it.

[0015] If the material is sufficiently stable and resilient, the connecting surfaces can be attached to a frame tube, for example, as elements soldered to a metal frame tube, or as compressed areas of a metal frame tube.

[0016] For bicycle frame materials made of other materials, the connection surfaces can be part of an additional component that is connected to the frame tube, e.g., part of a sleeve into which the frame tube is inserted, or a pin that is inserted into the frame tube. In a so-called carbon frame, which has frame tubes made of a CFRP material, the first and second connection means can be part of a component—e.g., a metallic component—that is laminated into the CFRP material, similar to the bottom bracket shell itself, dropouts, or the like, unless, in this case, the frame-side connection means are also designed as part of the bottom bracket shell.

[0017] According to the invention, the bicycle stand can be mounted as a so-called mid-mounted stand, i.e., between the front and rear wheels of the bicycle, without clamping the frame tubes. Rather, the second connection means on the frame side, designed as projections or recesses, provide a topography that enables a positive connection of the bicycle stand. For this purpose, they interact complementarily with corresponding projections or recesses of the bicycle stand, or they are designed as contact edges that rest against a correspondingly complementary section of the bicycle stand and limit its translational and / or rotational mobility. This positional fixation of the bicycle stand relieves the load on the first connection means, namely the fastening means, and supports a long-term secure fit of the bicycle stand on the bicycle frame.The first connecting elements on the frame side therefore serve solely as fastening elements to securely hold the bike stand to the bike frame. Since a large portion of the forces acting between the bike stand and the bike frame are absorbed by the form-fitting connection, the first connecting elements are correspondingly relieved of stress, significantly reducing the risk of the first connecting elements becoming loose.

[0018] In one embodiment, the first connection means are aligned horizontally and accessible from a rear-facing surface of the bicycle frame, for example from the back of the bottom bracket shell or from the back of the seat tube. This allows good accessibility to the first connection means. Furthermore, it is possible to attach further accessories, such as the rear wheel mudguard, to the frame-side connection means. The rear wheel mudguard runs in an arc around the rear wheel. The area of ​​the bottom bracket shell that allows the installation of a center stand and has the frame-side connection means is in many cases located approximately at the level of the rear wheel axle. The rear wheel mudguard therefore runs approximately vertically in the vicinity of the frame-side connection means, so that a rear wheel mudguard can be attached in this area.

[0019] For this purpose, in a first variant, the mudguard can be attached to the bicycle stand if the stand is specifically designed for this purpose and offers suitable fastening options, e.g., if the stand head has a threaded hole that serves to accommodate a mudguard fastening screw, or if it offers comparable fastening options, for example, for accommodating clips, retaining clamps, or the like. Or, in a second variant, the mudguard can be attached to the center stand by using a fastening element that serves to attach the center stand to the engine mount and simultaneously also serves to attach the rear wheel mudguard, for example, in the form of a screw that extends through the stand head and interacts with the frame-side connecting means.

[0020] In one embodiment, the first connection means are designed as holes. For example, they can be designed as through-holes, so that the aforementioned fastening elements, such as screws or rivets, can be inserted through these holes, thus ensuring a defined position of the fastening elements on the bicycle frame. However, the holes can also be designed as threaded holes. In this way, the bicycle stand can be mounted using screws, without the need to handle lock nuts or the like beyond the through-holes, thus simplifying the assembly of the bicycle stand.In particular, if the threaded holes are designed as blind holes and therefore only allow a limited penetration depth of the screws, damage to the bottom bracket or its housing is excluded, which would otherwise not be possible if the bike stand was improperly installed by using screws that were too long.

[0021] In one embodiment, two first connecting elements arranged at a distance from one another are used to attach the bicycle stand. This distribution of the holding forces between two first connecting elements enables force distribution over a larger area, which contributes to reducing the mechanical stress on the frame tubes. For example, the two first connecting elements can be arranged at a distance from one another and one above the other. This arrangement enables a particularly stable attachment of the bicycle stand, also with regard to the leverage forces acting on the fastening elements when the bicycle stand support is folded in and out.

[0022] In one embodiment, the second connecting means are elongated. This ensures particularly reliable positional fixation of the bicycle stand on the bicycle frame, because the elongated design of the second connecting means provides particularly good anti-twist protection. In one embodiment, the second connecting means extend transversely to the longitudinal direction of the bicycle frame, lying horizontally, so that sufficient space remains above and below the second connecting means to enable the aforementioned spaced-apart arrangement of the first connecting means one above the other.

[0023] The aforementioned elongated configuration of the second connecting means can be created, on the one hand, by a recess or a projection extending over this respective length. Alternatively, an elongated connection topography of the second connecting means can also be achieved by the second connecting means having two separate connecting elements, each configured as a projection or a recess and arranged at a distance from one another. These individual connecting elements can also be elongated in themselves or even have a circular geometry.

[0024] A play-free fit of the bicycle stand on the bicycle frame in the area of ​​the second connection means can be made possible by a corresponding design of the complementary interacting surfaces on the bicycle stand and the bicycle frame. For example, one or both components can have inclined surfaces so that, in the sense of a conicity, the two components are brought closer together and guided until the bicycle stand rests against the second connection means of the bicycle frame without play. For example, a prismatic recess can be provided on the bicycle frame, and a projection of the bicycle stand that dips into this recess can be conical or frusto-conical so that it can be inserted into the recess of the motor mount until it rests without play, thus ensuring a play-free fit of the bicycle stand on the bicycle frame.

[0025] The invention further relates to a bicycle stand intended for use as a center stand on a bicycle frame, wherein the bicycle frame has a number of the described features. In the context of the present invention, a number may refer to a singular or plural number of a corresponding feature. The bicycle stand comprises a stand head that can be attached to the connection means of the bicycle frame, and a support that is movable relative to the stand head between a raised riding position and a lowered support position, in which a foot of the support is intended to rest on the ground.

[0026] The bike stand is designed as a so-called side stand, which has a single support. In the support position, the support extends to just one side of the bike frame. Its length is sized so that the bike is tilted when supported on the side stand. The side stand enables particularly quick operation of the bike stand, because to move the support from its riding position to the support position, it simply needs to be folded out. The bike can then be tilted until the base of the bike stand touches the ground, meaning the bike, including both wheels, has contact with the ground at three points.

[0027] As an alternative to a side stand, the bike stand can also be designed as a so-called two-legged stand. A particularly secure stand for the bike during use can be achieved by designing the support of the bike stand as a two-legged stand. This ensures that a bike propped up with the stand is supported on both sides of the centerline of the bike frame, because the two feet of the support rest on the ground on either side of the centerline. The bike remains upright, so that the center of gravity of the bike remains within the diamond formed by the four contact points where the bike has contact with the ground.This particularly secure bicycle position is advantageous, for example, when the bicycle is parked with a relatively heavy load, weighing well into the tens of kilograms, as might be the case with larger shopping trips or with a child in a child seat. The two legs of the support can either always be roughly V-shaped or U-shaped, or they can be positioned side by side when the bicycle stand is in the riding position and swing apart when the support is lowered, so that the feet of both legs rest on the ground at spaced-apart points on either side of the centerline of the bicycle frame.

[0028] Thus, a bicycle frame can be provided that has an interface that, firstly, allows the mounting of either a two-legged center stand or a single-legged center stand. Secondly, the interface also offers the possibility of mounting mudguards in each of these two cases, and, furthermore, it also offers this possibility in a third case, namely when no bicycle stand is mounted.

[0029] Thanks to the interface provided by a bicycle frame according to the invention, the bicycle user has the option of choosing or switching between a sporty design with a low weight or a visually minimalist design with as few attachments as possible, namely without a bike stand, and possibly even without a rear mudguard. For typical family use, the bicycle can be equipped with a center stand as a central two-legged stand for multifunctional purposes, such as shopping or transporting children. And for use as a commuter vehicle between home and work, with a certain visual appeal, the bicycle can be equipped with a center stand as a side stand.

[0030] According to the invention, these possibilities can also be created for bicycles that are otherwise not intended to mount a bike stand and / or a mudguard between the two wheels, for example, if the bicycle frame does not actually allow this due to its structural suitability and / or aesthetic considerations. Bicycle frames made of, for example, CFRP are not suitable for a clamp fastening with the clamping forces required for a bike stand, and with other bicycle frames, the provision of obvious interfaces is not desired due to the desired, as "clean" as possible visual appearance. The interface according to the invention, on the other hand, blends in visually unobtrusively into the area.

[0031] In one embodiment, the head of the bicycle stand is designed in several parts, so that it has a connecting part that connects to the connecting means of the bicycle frame, as well as a joint part to which the support of the bicycle stand is connected in an articulated manner. This multi-part design of the head enables particularly economical production of the bicycle stand, since, for example, different connecting parts, with an otherwise identical bicycle stand construction, allow the bicycle stand to be connected to differently designed bicycle frames if these have different connecting means.

[0032] The invention further relates to the use of a bicycle stand, as known from DE 20 2022 101 272 U1, as a center stand on a "motorless" bicycle frame, which specifically has a bottom bracket shell and is free of a motor mount for a drive motor, and whose connection means are arranged near the bottom bracket shell. Such a bicycle stand has a head designed to be attached to connection means of a bicycle frame, not in the region of the rear wheel axle, but in the region of the bottom bracket shell. Furthermore, the bicycle stand has a support that is movable relative to the head between a raised riding position and a lowered support position, in which a foot of the support is designed to stand on the ground. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 20 2022 101 272 U1 [0005, 0006, 0011, 0032]

Claims

[1] Bicycle frame, with a bottom bracket shell, and with connecting means intended to connect a bicycle stand to or near the bottom bracket shell, • where first connection means ◯ are horizontally aligned ◯ and are designed to accommodate fastening means by which the bicycle stand is attached to the bicycle frame, • and wherein second connecting means ◯ are designed to accommodate the bicycle stand in a form-fitting manner ◯ and have a cross-section that deviates from circular, such that they ensure that the bicycle stand is non-rotatably attached to the second connecting means. [2] Bicycle frame according to claim 1, characterized by that the first connecting means are accessible from a rear-facing surface of the bicycle frame. [3] Bicycle frame according to claim 1 or 2, characterized bythat the first connection means are designed as bores, in particular as threaded bores. [4] Bicycle frame according to one of the preceding claims, characterized by that the bicycle frame has two first connecting means which are arranged at a distance from one another. [5] Bicycle frame according to one of the preceding claims, characterized by that the second connection means are designed as an elongated projection or as an elongated recess. [6] Bicycle frame according to one of the preceding claims, characterized by that the second connecting means have two connecting elements which are spaced apart from one another and designed as a projection or recess. [7] Bicycle frame according to one of the preceding claims, characterized by that the connecting elements are attached to the bottom bracket shell. [8] Bicycle frame according to one of claims 1 to 6, characterized by that the connecting surfaces are attached to a frame tube. [9] Bicycle frame according to one of claims 1 to 6, characterized by that the connecting surfaces are part of an additional component that is connected to a frame tube of the bicycle frame. [10] A bicycle stand intended for use as a central stand on a bicycle frame designed according to any one of the preceding claims, comprising a stand head intended to be attached to the connection means of the bicycle frame, and a support movable relative to the stand head between a raised riding position and a lowered supporting position in which a foot of the support is intended to rest on the ground. [11] Bicycle stand according to claim 10, characterized bythat the support is designed as a two-legged support, wherein the two legs of the support are spaced from each other in such a way that at least in the support position the two feet are arranged on either side of the center line of the bicycle frame. [12] Bicycle stand according to claim 10 or 11, characterized by that the stand head is designed in several parts, with a connecting part which is intended to be attached to the bicycle frame, and with a joint part to which the support is connected in an articulated manner. [13] Bicycle stand according to one of claims 10 to 12, characterized by that a bore, in particular in the form of a threaded bore, is arranged in the stand head, which is designed to serve to hold a rear wheel mudguard during use. [14] Use of a bicycle stand as a central stand • with a head designed to be attached to the connecting means of a bicycle frame, • and with a support which is movable relative to the head between a raised riding position and a lowered supporting position, in which a foot of the support is intended to stand on the ground on a bicycle frame, • which has a bottom bracket shell • and which is free of a motor mount for a traction drive motor, • and whose connecting means are arranged on or near the bottom bracket shell.