Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
A BICYCLE CHAIN CONTROL DEVICE
Document Type and Number:
WIPO Patent Application WO/2018/025113
Kind Code:
A1
Abstract:
This invention relates to a chain control device (10) for use with a bicycle. The device (10) comprises a body (20) with a base portion (22) and guiding means (30) which are adapted to engage with and guide a moveable chain motion control member (40) up and down the guiding means (30) in response to the movement of the chain which passes through it, thereby reducing or eliminating chain slap and chain drop.

Inventors:
SCHNEUWLY, Mathien Gabriel (46 Robins Rd, Observatory, 7925 Cape Town, 7925, ZA)
Application Number:
IB2017/054414
Publication Date:
February 08, 2018
Filing Date:
July 21, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
SCHNEUWLY, Mathien Gabriel (46 Robins Rd, Observatory, 7925 Cape Town, 7925, ZA)
International Classes:
B62M9/126
Foreign References:
US20070265121A12007-11-15
DE102013109178A12015-02-26
Attorney, Agent or Firm:
SPOOR & FISHER et al. (11 Byls Bridge Boulevard, Building No. 14 Highveld Ext 73, 0157 Centurion, 0157, ZA)
Download PDF:
Claims:
CLAIMS

1. A chain control device, suitable for use with a bicycle having a bicycle frame and a chain, the device comprising a body and guiding means adapted to engage with and guide a moveable chain motion control member between a first position towards the bicycle frame and a second position away from the bicycle frame in response to the movement of the chain passing through the motion control member.

2. A chain control device according to claim 1 , wherein the base portion is reieasably securable to the bicycle frame in use.

3. A chain control device according to claim 1 or 2, wherein the moveable chain motion control member comprises movement resistance means adapted to engage the guiding means to provide resistance to movement imparted by the chain on the chain motion control member.

4. A chain control device according to claim 3, wherein the movement resistance means is a set of complementary apertures through the moveable chain motion control member, and wherein the apertures each abut the guiding means, thereby providing resistance to movement imparted by the chain.

5. A chain control device according to any one of the preceding claims, wherein the moveable chain motion control member is a tubular member comprising a channel for receiving the chain in use.

6. A chain control device according to any one of the preceding claims, wherein the guiding means comprises a set of substantially parallel legs extending from the base portion.

7. A chain control device according to claim 6, wherein the distal ends of the substantially parallel legs are connected, thereby limiting the distance that the moveable chain motion control member can travel away from the first position.

8. A chain control device according to claim 6 or claim 7, wherein the proximal ends of the substantially parallel legs are secured to the base portion.

9. A chain control device according to claim 8, wherein the proximal ends of the legs each form a hook section which is housed within the base portion.

10. A chain control device according to claim 2, wherein the base portion comprises a set of securing arrangements for securing the device to the bicycle frame.

11. A chain control device according to claim 10, wherein the securing arrangement is a set of apertures in the base portion for receiving fastening means, including cable ties, in use.

12. A chain control device according to any one of the preceding claims, wherein the guiding means are integrally molded into or connected with the base portion.

13. A chain control device according to claim 2, which is releasably secured to the bicycle frame in use at a point approximately midway between the crankset and rear wheel cassette of the bicycle.

14. A chain control device according to claim 1 , substantially as herein described and illustrated.

Description:
A BICYCLE CHAIN CONTROL DEVICE

INTRODUCTION

This invention relates to a chain control device for use with a bicycle. In particular, but not exclusively, the invention relates to a chain control device for use with an off road mountain bike to mitigate against undesirable chain movement including but not limited to chain slap and chain drop.

BACKGROUND

Off road (mountain bike) riding often encounters rough terrain, riding uphill or downhill over roots, jumps and rocks. While riding this type of terrain, the bicycle chain will swing around and generally move and sway in an undesirable manner both vertically and laterally.

This undesirable movement of the bicycle chain results in what is commonly referred to as "chain slap" and/or "chain drop". "Chain slap" refers to the undesirable movement of the chain from riding over rough terrain which leads to the chain striking various parts of the bicycle frame and components, which causes damage and scratches as well as an unpleasant and distracting noise. "Chain drop" on the other hand refers to the derailing of the chain from the desired chain ring and/or cassette sprocket, leading to loss of pedalling ability, incorrect gear selection, chain suck and chain jamming. Chain slap typically results in chain drop.

A common device which attempts to reduce chain drop is typically what is referred to as a chain guide which will typically have a structure which positions openings close to the chain ring through which the chain is forced to go. If there is any chain movement the chain will bump against the walls of the guides and end up back on in the right place. The rear deraiileur clutch mechanism slows down the movement of the chain by absorbing its energy in a friction device located in the deraiileur cage pivots. The result is that the movements of the chain are less drastic and thus less likely to cause problems.

Chainstay protectors are made of soft materials which are wrapped onto vulnerable parts of the frame; typically the chainstay. Chainstay protectors are also referred to as "s!ap socks" and are intended to absorb energy from being struck by the chain, thereby limiting damage and noise. These devices focus on the effects of chain slap rather than the cause.

"Chain guards" are designed to ensure that the chain will not drop from the chain ring. They are bulky, costly and add weight to the bicycle. They do not address chain slap. Clutch type rear derai!leurs are not effective enough to eradicate chain slap, there is still noise and damage to frames, so slap socks are needed as protection. Slap socks protect the frame but they do little against noise and the eventual chain drop on the cassette.

There is therefore a need for a chain control device that addresses at least some of the shortcomings experienced with the devices of the prior art. SUMMARY OF THE INVENTION

According to a first aspect to the present invention there is provided a chain control device suitable for use with a bicycle having a bicycle frame and a chain, the device comprising a body having a base portion and guiding means adapted to engage with and guide a moveable chain motion control member between a first position towards the bicycle frame and a second position away from the bicycle frame in response to the movement of the chain passing through the motion control member. in one embodiment of the invention, the base portion is releasably securable to the bicycle frame in use.

In one embodiment of the invention, the moveable chain motion control member comprises movement resistance means adapted to engage the guiding means to provide resistance to movement imparted by the chain on the chain motion control member.

In one embodiment of the invention, the movement resistance means is a set of complementary apertures through the moveable chain motion control member, and wherein the apertures each abut the guiding means, thereby providing resistance to movement imparted by the chain.

Preferably, the moveable chain motion control member is a tubular member comprising a channel for receiving the chain in use.

In a preferred embodiment of the invention the guiding means comprises a set of substantially para!!el legs extending from the base portion.

Preferably, the distal ends of the substantially parallel legs are connected, thereby limiting the distance that the moveable chain motion control member can travel away from the first position. Preferably, the proximai ends of the substantially parallel legs are secured to the base portion.

Even more preferably, the proximal ends of the legs each form a hook section which is housed within the base portion.

In one embodiment of the invention, the base portion comprises a set of securing arrangements for securing the device to the bicycle frame.

Preferably, the securing arrangement is a set of apertures in the base portion for receiving fastening means, including cable ties, in use.

Even more preferably, the guiding means are integrally molded into the base portion.

The device may be reieasab!y secured to the bicycle frame at a point approximately midway between the crankset and rear wheel cassette of the bicycle.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail with reference to the following non-limiting embodiments and figures in which:

Figure 1 shows an isometric view of a chain control member according to one embodiment of the present invention;

Figure 2 shows a left side view of a chain control member according to one embodiment of the present invention;

Figure 3 shows a rear view of a chain control member according to one embodiment of the present invention;

Figure 4 shows a cross sectional rear-view of the base portion incorporating the guiding means; Figure 5 shows an isomeric view of a chain control member according to an alternative embodiment of the present invention; and

Figure 6 shows an isomeric view of a chain control member according to a further embodiment of the present invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The present invention will now be described more fully hereinafter with reference to the accompanying figures, in which some of the non-limiting embodiments of the invention are shown.

The invention as described hereinafter should not be construed to be limited to the specific embodiments disclosed, with slight modifications and other embodiments intended to be included within the scope of the invention.

Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

As used herein, throughout this specification, the singular forms "a", "an" and "the" include the plural form, unless the context clearly indicates otherwise.

The terminology and phraseology used herein is for the purpose of description and should not be regarded as limiting. The use of the terms "comprising", "containing", "having", "including", and variations thereof used herein, are meant to encompass the items listed thereafter, and equivalents thereof as well as additional items.

The present invention provides for a chain control device which is designed for use with a bicycle, in particular a mountain bike. The chain control device of the present invention is specifically designed and adapted to be secured to the frame of a bicycle and to receive the chain of the bicycle through a moveable part thereof. The chain control device according to the present invention addresses the phenomena commonly referred to as "chain slap" and/or "chain drop" and the associated effects thereof.

As used herein, the term "chain slap" refers to the undesirable movement of the chain when riding over rough terrain resulting in the chain striking various parts of the bicycle frame and components, which may cause damage and scratches in addition to undesirable noise.

As used herein, the term "chain drop" refers to the derailing of the chain from the desired/selected chain ring and/or cassette sprocket, resulting in a loss of pedalling ability, incorrect gear selection, chain suck and chain jamming. Chain slap typically results in chain drop.

With reference to Figure 1 , a chain control device 10 comprises a body 20 which consists of a base portion 22. The base portion 22 is designed to be releasably securable to a bicycle frame (not shown) when the device is in use. It is envisaged that the base portion 22 may be made from a partially flexible material, or may include partially flexible portion that abuts the frame in use, so that it may be securely fastened to a bicycle frame when in use and allow for lateral shifting associated with gear changes.

In Figure 1 the base portion 22 is provided with a set of apertures 24 and 26 through which fasteners such as cable ties or zip ties can pass. Once threaded through the apertures the cable ties are wrapped around the bicycle frame when the device has been placed on the frame, and tightened in the normal manner, thereby to secure the device in an optimal position approximately midway between the crankset and rear wheel cassette where the amplitude of the chain is expected to be the greatest, or wherever is most suitable with regards to the chainline variations of the bicycle due to gear changes, angle of the chain stay and the device being able to function best. It will be appreciated that the device could be installed above the chainstay facing upwards towards the bicycle seat, or below the chainstay facing downwards towards the surface on which the bicycle is standing. Furthermore, the frame of the bicycle may be adapted to include features which assist with the installation of the device, including the positioning thereof on the chainstay.

The embodiment shown in Figure 1 shows basic apertures through the base portion 22, but it will be appreciated by those skilled in the art that the apertures are merely one example of a potential securing arrangement for the chain control device. Other examples of suitable securing arrangements would include one or more slots for receiving one or more Velcro straps, a suitably sized snap-lock type arrangement, or any other mechanical device for securing the chain control device around a bicycle frame member, such as a round section of tube, an oval tube, or any other shape of frame section between the crankset and rear wheel cassette, commonly referred to as the "chainstay". Additionally the device can be mounted on an alternative frame member if the frame does not employ a typical chainstay arrangement.

Figure 6 shows an alternative embodiment of the invention wherein the chain control device 10 may be integrally formed with the chainstay section of a bicycle frame. In this embodiment the guiding means 30 would protrude from or extend from the frame, with the portion of the frame fulfilling the function of the base portion 22.

The chain control device 10 comprises guiding means 30 which are adapted to engage with and guide a moveable chain motion control member 40. In the embodiment shown in Figure 1 , the guiding means 30 consist of two substantially parallel legs extending from the base portion 22.

The substantiaily parallel legs, which can also be one or more tracks or rails, are indicated by reference numerals 32 and 34 in Figure 3. The guiding means, or at least the substantially parallel legs thereof, may be made from any resilient material such as a resilient metal or metal alloy, for example stainless steel. The combination of the resilient legs extending from the base portion allows for the guiding means 30 to be biased towards the upright starting position.

As can be seen from Figures 1 and 3, the guiding means 30 is adapted to engage with and guide a moveable chain motion control member 40 along the length of the !egs 32 and 34 of the guiding means. Once the chain control device is installed on the frame of the bicycle, or when it is integrally formed with the frame, the chain of the bicycle will be passed through the chain motion control member 40.

As is shown in Figure 2, the chain motion control member 40 is reversibly moveable, substantially in a plane defined by the legs 32 and 34, between a first position (A) towards the bicycle frame and a second position (B) away from the bicycle frame in response to the movement ("chain slap") of the chain which passes through the channel in the motion control member. The motion control member is also moveable in these directions in response to the movement of the chain as a result of a normal gear change.

As has been described above, the guiding means 30 is made from a resilient material, while the base portion 22 is made from a flexible material. As is indicated in Figure 2, this configuration allows for the guiding means 30 to move away from the plane defined by the direction of movement from (A) - (B), in the directions (C) and (D), pivoting about a point of entry 28 into the base portion. This configuration of the guiding means 30 and the base portion 22 allows for the guiding means to be biased towards the upright starting position (E). Where the control device 10 is integrally formed with the bicycle frame, this flexibility of the guiding means 30 can be provided by having sections of the legs 32 and 34 made from a flexible material, alternatively having any other flexibility points of fixation to the bicycle frame.

In a preferred embodiment of the invention, such as is shown in Figure 1 , the legs, rails, or tracks of the guiding means 30 are connected to each other at the distal end thereof, thereby to define a fixed path length between the base and the top of the guiding means. The top of the guiding means therefore establishes the maximum distance that the motion control member 40 can travel away from the bicycle frame in use.

The movement away from and towards the bicycle frame, and away from and towards the upright starting position (E) is a continuous response to the up and down movement of the chain as the bicycle is ridden over rough terrain, as well as the more pronounced movement of the chain associated with the normal changing of gears.

The movement of the chain motion control member 40 away from and towards the bicycle frame, as described above, in response to the movement of the chain which passes through the member, is dampened by movement resistance means which are adapted to frictionally (or otherwise) engage the legs or tracks of the guiding means in use.

In the example shown in Figures 1 to 3, the movement resistance means are provided as two sets of apertures 41a, 41 b and 42a, 42b through which the legs 32 and 34 are received. The motion control member 40 is preferably a material that has the required flexibility to engage the legs, which passes through the apertures therein, with sufficient frictional force to act against the force imparted on the motion control member thereby to limit the movement thereof in response to chain slap and chain drop, whilst remaining freely moveable in response to normal gear changing functions. in one embodiment of the invention, as is shown in Figure 5, the motion control member 40 has edges 44 and 46 which are tapered away from, or flared outward away from, the opening 48 in the control member 40. These smoothly tapered or flared edges are adapted to eliminate any undesirable limitation of the movement of the chain by sharp edges, thereby allowing for efficient passage of the chain through the opening 48.

In a preferred embodiment of the invention the legs 32 and 34 are secured to the base portion 22 of the device by means of a hook portion 52 provided at the distal end of each leg. The hook portion of the leg is secured within the base portion, which may be integrally moulded around the guiding means. The hook portion 52 of each leg may also pass around and under the outer periphery of the apertures in the base portion, as is shown in Figure 4. it will be appreciated that this configuration provides additional reinforcement for the securing arrangement of the device.

In a preferred embodiment of the invention the base is made of a flexible material to allow for movement in a plane required for gear changes. It will be appreciated by those persons skilled in the art that the dynamic action of the chain control device permits it to be installed approximately midway between the crankset and rear wheel cassette. This optimised position has the advantage of tackling "chain slap" where the amplitude thereof is the greatest.

The guiding means 30 which engages with and carries the chain motion control member 40 resists its' movement by means of friction. Therefore, the device achieves the damping of the movement of the chain in a simple and effective manner. The practical result of the device is that the chain is still permitted to move in the directions indicated by (A) - (D) in Figure 2 as the various gears require, yet the undesired high speed movements of the chain are filtered out by the above described dampening effect provided by the movement resistance means of the chain motion control member in combination with the guiding means.

This above description of some of the illustrative embodiments of the invention is to indicate how the invention can be made and carried out. Those of ordinary skill in the art will know that various details may be modified thereby arriving at further embodiments, but that many of these embodiments will remain within the scope of the invention. For example, it will be appreciated that the chain motion control member may be manufactured in a different shape or from a different material, that the apertures therein may be replaced by an alternative movement resistance mechanism that cooperates with the guiding means, and that the base portion may be secured to the frame in a number of ways.