CHAIN ​​GUIDE WITH PRE-TENSIONED GUIDE ELEMENTS

Description

[0001] The innovative concept described herein concerns a chain guide for guiding the chain of a chain drive in vehicles, particularly two-wheelers. The chain guide can prevent the chain from unintentionally falling off a sprocket or similar component.

[0002] Chain drives are a proven method for transmitting power to the driven wheel(s) in vehicles. Drive chains are particularly common in bicycles and motorcycles. For example, in bicycles, a drive chain transmits power from the crank arm and the attached drive sprocket or chainring to the rear wheel. In motorcycles, mopeds, and similar vehicles, as well as e-bikes, pedelecs, and the like, the drive chain transmits the motor's power from the drive sprocket to the rear wheel.

[0003] Bicycles with gears typically have a derailleur. This is attached to the rear triangle of the frame near the rear axle by means of a derailleur hanger, also called a dropout. The derailleur moves the chain across the different sprockets of the cassette to shift gears. Such a derailleur has a spring-loaded arm to compensate for the different chain lengths on different sprockets and thus maintain chain tension.

[0004] Impacts to the rear wheel, for example when riding down a curb or descending a mountain bike, can cause the derailleur's spring-loaded arm to snap forward unintentionally. This briefly reduces chain tension, causing the chain to sag. Due to this lack of tension, the loose chain can detach from the drive-side chainring and fall off.

[0005] This problem can also occur on bicycles without a derailleur. For example, if the chain tension is generally too low. Here, too, there is a risk that the chain will come loose from the drive-side sprocket or chainring when the rear wheel is subjected to impacts.

[0006] To address this problem, so-called chain guides are available, as described, for example, in EP 1 367 227 A2 or in EP 2 140 170 A1.

[0007] In the bicycle sector, chain guides are offered particularly for downhill-oriented mountain bikes, as these bikes are more prone to the impacts on the rear wheel described above. Chain guides come in various designs and placement options. However, all chain guides share a guide slider through which the chain runs. This guide slider keeps the chain largely in place, significantly minimizing the risk of it falling off.

[0008] These types of guide carriages are usually designed in two parts. To insert the chain, the carriage is opened by moving the two carriage parts against each other. After inserting the chain, the two carriage parts are then screwed together, allowing the chain to run between them. The screw connection provides a secure and robust way of attaching the two carriage parts. However, practical experience has shown that this screw connection is impractical because the chain guide cannot be opened again without tools, for example, to repair the chain on the road or to release the chain in the event of a chain suck.

[0009] In another version, the two slider sections are held together with a snap-fit ​​fastener. This allows the slider to be opened and closed without tools. However, it has been shown that this type of fastening is only partially suitable, as the snap-fit ​​fastener can open while riding, causing the slider to open and the chain to become unguided. This is particularly noticeable on downhill bikes or during rough descents off-road. Furthermore, the snap-fit ​​fastener tends to loosen over time.

[0010] It is therefore an object of the present invention to improve existing concepts of chain guides in such a way that the guide carriage can be opened and closed easily and preferably without tools, while still maintaining a firm and secure connection between the individual carriage parts.

[0011] This objective is achieved by a chain guide according to claim 1. Further embodiments and advantageous aspects of this chain guide are mentioned in the respective dependent claims.

[0012] The chain guide according to the invention serves to guide a drive chain of a vehicle with a chain drive. The chain guide has a mounting part by means of which the chain guide is mounted to the respective vehicle. The chain guide also has a guide carriage attached to the mounting part, which guides the drive chain when the chain guide is mounted on the vehicle. The guide carriage has a first guide element and a second guide element rotatable relative to it, wherein the drive chain to be guided runs between these two guide elements when the chain guide is mounted on the vehicle. According to the invention, the two guide elements are pre-tensioned against each other by means of a pre-tensioning device, transversely to the direction of travel of the chain. Due to the pre-tension, the two guide elements hold each other together, in the manner of a pre-tensioned clamp.When this preload is applied, a considerable force is required to twist the two guide elements against each other. In some cases, a mechanical locking mechanism is provided to prevent the two guide elements from twisting while preloaded. Only when the two guide elements are moved translationally away from each other, against the preload force, can they then be twisted against each other. This ensures that the two guide elements are firmly connected while preloaded, preventing them from unintentionally opening during operation. Conversely, the guide carriage can be easily opened, for example for maintenance purposes, by first releasing the two guide elements against the preload force and then twisting them against each other.

[0013] Some exemplary embodiments are shown in the drawing and are explained below. They show: Fig. 1 is an exploded view of a chain guide according to an embodiment according to the invention, Fig. 2A is a schematic top view of a chain guide in the closed state according to an embodiment, Fig. 2B is a schematic top view of a chain guide in the open state according to an embodiment, and Fig. 3 is a schematic top view of a second guide element with teeth according to an embodiment.

[0014] The following are examples of embodiments described in more detail with reference to the figures, whereby elements with the same or similar function are provided with the same reference numerals.

[0015] The chain guide described herein is suitable for vehicles powered by a chain drive. This means that the chain guide connects the vehicle's drive (e.g., pedal crank, motor, etc.) to the vehicle's output (gearbox, sprocket set, cassette, rear wheel, etc.). The vehicle can be, for example, a single-track vehicle, particularly a two-wheeler. This includes, for example, unmotorized bicycles powered by a pedal crank, as well as motorized bicycles, such as e-bikes and pedelecs, which have an additional motor, especially an electric motor. The chain guide described herein is also suitable for motorized two-wheelers, such as mopeds, motorcycles, and the like, provided they have a chain drive. Furthermore, multi-track vehicles with a chain drive, such as quads and the like, fall under the definition of "vehicle" as used herein.For the following description of the chain guide according to the invention, reference is made to a bicycle purely by way of example. However, all statements and explanations made herein generally apply to all vehicles with chain drive, in particular to the categories of vehicles mentioned at the beginning of this paragraph.

[0016] Figure 1Figure 1 shows an exploded view of a chain guide 100 according to the invention. The chain guide has a mounting part 110 by means of which the chain guide 100 is mounted to the vehicle. For example, the mounting part 110 can have an attachment section 111, which is attached to the frame of a bicycle in an area around the bottom bracket. As shown here by way of example, the attachment section 111 can have elongated holes for screws. The screws are guided through the elongated holes and engage with corresponding threaded bores in the bicycle frame behind them. Thus, the entire mounting part 110 can be mounted on the vehicle or bicycle.

[0017] The chain guide 100 also has a guide carriage 120 attached to the mounting part 110. According to the invention, the guide carriage 120 is designed in multiple parts (e.g., at least two parts). The guide carriage 120 has at least a first guide element 121 and a second guide element 122 rotatable relative to it.

[0018] The guide carriage 120 serves to guide the drive chain, with the drive chain to be guided running between the two guide elements 121, 122 when the chain guide 100 is mounted on the vehicle.

[0019] For clarity, the chain to be guided is not shown here. However, when the chain guide 100 is assembled and mounted on the vehicle, it runs between the two guide elements 121 and 122, as indicated by arrow 130. This arrow 130 also symbolizes the direction of travel of the chain.

[0020] According to the invention, the two guide elements 121, 122 are pre-tensioned against each other by means of a pre-tensioning device 140, transversely to the direction of travel 130 of the chain. That is, the first guide element 121 is pressed towards the second guide element 122 by means of the pre-tensioning device 140, which is caused by the force vector F Figure 1 shows the second guide element 122 being pressed towards the first guide element 121 by means of the preloading device 140, which is caused by the force vector F 2 is shown.

[0021] As mentioned at the beginning, the two guide elements 121, 122 are pre-tensioned against each other transversely to the direction of travel 130 of the chain. That is to say, the force vectors F 1 and F 2 run perpendicular to the chain direction 130. This can be understood in particular to mean that the force vectors F 1 and F2 are essentially orthogonal to the chain direction 130. Thus, the two guide elements 121, 122 would also be pre-tensioned against each other essentially orthogonal to the chain direction 130.

[0022] The first guide element 121 is fixed to the mounting part 110 against rotation. The second guide element 122 is rotatable relative to the first guide element 121. As mentioned at the outset, the second guide element 122 is pre-tensioned towards the first guide element 121. The two guide elements 121, 122 thus have a kind of pre-tensioned clamping connection, whereby they are attracted to each other due to the pre-tension. The mutual attractive forces, i.e., the force vectors F 1 and F 2 , can be so strong that a rotation of the second guide element 122 is not possible.

[0023] In order to rotate the second guide element 122 relative to the first guide element 121, the preload must first be released. According to the invention, the guide carriage 120 is designed such that the second guide element 122 must first be moved away from the first guide element 121 in order to release it from the first guide element 121 against the preload, before it can then be rotated relative to the first guide element 121.

[0024] Figure 2A shows A frontal view of the chain guide 100 according to the invention in an assembled state, where the guide carriage 120 is closed. That is, the first guide element 121 and the second guide element 122 are congruently opposite each other, so that the chain can run between the two guide elements 121, 122. This corresponds to the state of the chain guide 100 in operation.

[0025] In this closed state, the preloading device 140 can have a lower locking position. This means that the second guide element 122 can lock securely in this position, preventing it from rotating relative to the first guide element 121 when the preload forces are applied. F 1 and F 2. Here again, the following applies: According to the invention, the second guide element 122 must first be moved away from the first guide element 121 to release the preload. Only then does the second guide element 122 release from its lower locking position and can be rotated relative to the first guide element 121. In this case, it could, for example, be folded upwards to open the guide carriage 120 (see Figure 2B ).

[0026] Figure 2BFigure 1 shows a frontal view of the chain guide 100 according to the invention in an assembled state, with the guide carriage 120 open. That is, the second guide element 122 is rotated relative to the first guide element 121 and folded upwards. In this open state, the chain can be removed from the chain guide 100.

[0027] Here, the preloading device 140 can have an upper locking position. This means that the second guide element 122 can lock into this flipped-up position, so that it can no longer rotate relative to the first guide element 121 when the preload forces are applied. F 1 and F2. Here again, the following applies: According to the invention, the second guide element 122 must first be moved away from the first guide element 121 to release the preload. Only then does the second guide element 122 release from its upper locking position and can be rotated relative to the first guide element 121. In this case, it could be folded down again to close the guide carriage 120 (see Figure 2A ).

[0028] The described locking positions can be achieved, for example, by means of suitable tooth contours, as will be explained later with reference to the Figure 1 and 3 will be explained in more detail.

[0029] First, let us reiterate Figure 1 Referenced. Here it can be seen that the two guide elements 121, 122 are rotatable relative to each other along a common axis of rotation 150, and that the pre-tensioning device 140 is also arranged along this axis of rotation 150.

[0030] In this exemplary embodiment, the pre-tensioning device 140 has an adapter piece 141. This adapter piece 141 is arranged, viewed along the axis of rotation 150, between the first guide element 121 and the second guide element 122. The adapter piece 141 is designed to fix the first guide element 121 to the mounting part 110 in a rotationally fixed manner.

[0031] For this purpose, the adapter piece 141 can have a contour 142 on a side facing the first guide element 121, which is designed to engage with a complementary contour 143 formed in the first guide element 121, thereby establishing a positive-locking and rotationally fixed connection with the first guide element 121. These contours 142, 143 can be specific, mutually complementary shapes that can be formed in both the adapter piece 141 and the first guide element 121. These complementary contours 142, 143 fit together according to the lock-and-key principle and form a positive-locking and rotationally fixed connection. Figure 1 A round adapter piece 141 with two flattened edges is shown as a purely exemplary example. This shape (round with flattened edges) is also found accordingly in the first guide element 121 (see reference numeral 143).

[0032] The mounting part 110 can also have a corresponding contour 144, which is complementary to the contour 142 of the adapter piece 140. The adapter piece 141 can extend through the complementary contour 143 in the first guide element 121 and reach the complementary contour 144 of the mounting part 110. The adapter piece 141 can be fixed to the rear of the mounting part 110, i.e., from a side facing away from the first guide element 121, by means of a screw. This fixes the adapter piece 141 to the mounting part 110, whereby the adapter piece 141, by means of the complementary contours 142 and 143, simultaneously also secures the first guide element 121 to the mounting part 110 in a rotationally fixed manner.

[0033] The adapter piece 141 is also designed to rotatably fix the second guide element 122 to the mounting part 110 relative to the first guide element 121. For this purpose, the adapter piece 141 can have a toothed section 145 on a side facing the second guide element 122, which is designed to engage with a complementary toothed section 146 (see Figure 3) formed in the second guide element 122, in order to allow stepwise rotation of the second guide element 122 relative to the first guide element 121.

[0034] Figure 3 Figure 1 shows a top view of the second guide element 122 with a corresponding toothing 146. This toothing 146 engages with the complementary toothing 145 in the adapter piece 141 (see Figure 1). Figure 1 Thus, the second guide element 122 can be rotated stepwise, i.e., tooth by tooth. This allows, for example, the previously mentioned adjustments to the Figures 2A and 2BThe described locking positions can be implemented. For example, a first pair of teeth could provide a rotationally fixed connection in the lower locking position, and a second pair of teeth could provide a rotationally fixed connection in the upper locking position. Additional pairs of teeth between the first and second pairs can therefore be optional.

[0035] The second guide element 122 is attached to the adapter piece 141 in such a way that the teeth 145, 146 can be released by moving them against the preload. That is, in order to rotate the second guide element 122, the second guide element 122 must first be moved against the preload, according to the invention. F 1 and F 2 can be pulled out. This releases the toothing 145, 146 between the second guide element 122 and the adapter piece 141, and the second guide element 122 can be rotated.

[0036] Figure 1Figure 1 shows a possible embodiment for realizing this toothing 145, 146, which can be released against the preload. For this purpose, a preloading element 160 and a locking element 170 are provided on a side of the second guide element 122 opposite the adapter piece 141. These components are part of the preloading device 140 described above; that is, in this example, the preloading device 140 comprises the adapter piece 141, the preloading element 160, and the locking element 170.

[0037] The preloading element 160 generates the preload forces required for the mutual preloading of the two guide elements 121, 122. F 1 and F 2. The preloading element 160 can, for example, be a spring. The fixing element 170 can, for example, be a screw. The screw head can be designed in such a way that the preloading element 160 is supported by it.

[0038] The second guide element 122 can now be attached to the adapter piece 141 by means of the fixing element 170 in the sense of an axial clearance fit, such that the second guide element 122 is axially displaceable along the axis of rotation 150. That is, without the preload element 160, the second guide element 122 would be freely movable on the fixing element 170 due to the clearance fit. However, since the preload element 160 is arranged between the second guide element 122 and the fixing element 170 (to generate the preload), the second guide element 122 is pressed towards the first guide element 121 by the preload element 160, and the axial clearance fit is compensated for by the preload force.

[0039] In Figure 3A toothed section 146 was shown as an example of a contour that allows the second guide element 122 to be rotated stepwise (tooth by tooth) relative to the first guide element 121. However, it would also be conceivable that instead of the toothed section, a toothless friction surface could be present on both the adapter piece 141 and the second guide element 122. This toothless friction surface could, for example, be in the form of a cone. In this case, the frictional force on the cone could be increased when a preload force is applied. F 1 and F2. The height of the second guide element 122 must be such that rotation relative to the first guide element 121 is not possible. According to the invention, rotation would only be possible after the second guide element 122 is moved away from the first guide element 121 against the preload. Due to the lack of teeth, i.e., the toothless contour, stepless rotation of the second guide element 122 relative to the first guide element 121 would be possible.

[0040] Due to the preloading of the two guide elements 121, 122 described herein according to the invention, the guide carriage 120 can be opened and closed without tools. Additionally, the preload forces F 1 and F 2 sufficiently large to prevent unintentional opening of the guide carriage 120 during travel.

[0041] The embodiments described above merely illustrate the principles of the innovative concept described herein. It is understood that modifications and variations of the arrangements and details described herein will be obvious to other people skilled in the art. Therefore, it is intended that the concept described herein be limited only by the scope of protection set forth in the following patent claims and not by the specific details presented herein by way of description and explanation of the embodiments.

Claims

1. Chain guide (100) for guiding a drive chain of a vehicle, the chain guide (100) comprising: a mounting part (110) by means of which the chain guide (100) is mounted on the vehicle, and a slider (120) mounted on the mounting part (110) for guiding the drive chain, wherein the slider (120) comprises a first guide element (121) and a second guide element (122) rotatable relative thereto, wherein the drive chain to be guided passes between these two guide elements (121, 122) when the chain guide (100) is mounted on the vehicle, and wherein the two guide elements (121, 122) are preloaded against each other by means of a preloading device (140), transversely to the running direction (130) of the chain, characterized in that the slider (120) is configured such that the second guide element (122) has to be first moved away from the first guide element (121) in order to release the same from the first guide element (121) against the preload before the same can subsequently be rotated relative to the first guide element (121).

2. Chain guide (100) according to claim 1, wherein the first guide element (121) is non-rotatably mounted on the mounting part (110), and wherein the second guide element (122) is rotatable with respect to the first guide element (121) and is preloaded towards the first guide element (121).

3. Chain guide (100) according to any one of the preceding claims, wherein the preload device (140) comprises a lower latching position in which the slider (120) is closed, and in which the second guide element (122) is fixed non-rotatably relative to the first guide element (121).

4. Chain guide (100) according to any one of the preceding claims, wherein the preload device (140) comprises an upper latching position in which the slider (120) is open, and in which the second guide element (122) is fixed non-rotatably relative to the first guide element (121).

5. Chain guide (100) according to any one of the preceding claims, wherein the two guide elements (121, 122) are rotatable relative to each other along a common rotation axis (150), and wherein the preload device (140) is arranged along this rotation axis (150).

6. Chain guide (100) according to claim 5, wherein the preload device (140) comprises an adapter piece (141), wherein the adapter piece (141) is arranged along the rotation axis (150) between the first guide element (121) and the second guide element (122), and wherein the adapter piece (141) is configured to fix the first guide element (121) to the mounting part (110) non-rotatably relative to the same and to fix the second guide element (122) to the mounting part (110) rotatably relative to the first guide element (121).

7. Chain guide (100) according to claim 6, wherein the adapter piece (141) comprises, on a side facing the first guide element (121), a contour (142) that is configured to engage in a complementary contour (143) formed in the first guide element (121) in order to establish a form-fit and non-rotatable connection with the first guide element (121).

8. Chain guide (100) according to claim 6 or 7, wherein the adapter piece (141) comprises, on a side facing the first guide element (121), a contour (142) that is configured to engage in a complementary contour (144) formed in the mounting part (110) in order to establish a form-fit and non-rotatable connection with the mounting part (110).

9. Chain guide (100) according to any one of claims 6 to 8, wherein the adapter piece (141) comprises, on a side facing the second guide element (122), a contour that is configured to allow a continuous rotation of the second guide element (122) relative to the first guide element (121).

10. Chain guide (100) according to any one of claims 6 to 8, wherein the adapter piece (141) comprises, on a side facing the second guide element (122), a toothing (145) that is configured to engage in a complementary toothing (146) formed in the second guide element (122) in order to allow a stepwise rotation of the second guide element (122) relative to the first guide element (121).

11. Chain guide (100) according to claim 10, wherein the second guide element (122) is mounted on the adapter piece (141) such that a release of the toothings (145, 146) is possible by means of a movement against the preload.

12. Chain guide (100) according to any one of claims 6 to 11, wherein a preload element (160) and a fixing element (170) are provided on a side of the second guide element (122) opposite the adapter piece (141), wherein the second guide element (122) is mounted on the adapter piece (141) by means of the fixing element (170) in the sense of an axial clearance fit, so that the second guide element (122) is axially displaceable along the rotation axis (150), and wherein the preload element (160) is arranged between the second guide element (122) and the fixing element (170) in order to generate the preload and to compensate for the axial clearance fit.