Bicycle control device having a rotatable dial

Abstract: A bicycle control device includes a base member (1) adapted to be mounted to a structural member of a bicycle, a dial (2) rotatably mounted to the base member (1), a detent mechanism operatively associated with the dial (2) for providing a detenting force to the dial (2) at a plurality of rotational positions of the dial (2) , and a first electromagnetic switching member (22) operated by the dial (2) for selectively electromagnetically communicating with a second electromagnetic switching member (13) when the dial (2) is positioned at each of the plurality of rotational positions. A button (4,5) and/or display (3) may be disposed in proximity to the dial (2) to allow the rider to control the bicycle transmission and to view the status of the selected gears, respectively.

Description: BACKGROUND OF THE INVENTION The present invention is directed to bicycle control devices and, more particularly, to a bicycle control device that includes a rotatable dial that may be manipulated by the rider's hand. Some bicycles that have been proposed feature the use of an automatic shifter, whereby bicycle shifting is managed by an electric motor, actuator, or the like, and automatic shifting is managed on the basis of detected data such as the bicycle speed, the torque applied to the crank spindle, and the like. The automatic shifting of such automatic shifters should have a plurality of automatic shifting modes, such as an automatic shifting mode for flat terrain and an automatic shifting mode for uphill terrain. This is because the optimal shift timing varies depending on the incline of the road, the operator leg power, and the like. It is also sometimes necessary to switch from automatic shifting mode to manual shifting mode. In the past, a lever type of switch has been used to switch between the plurality of shifting modes. However, because conventional lever types of switches protrude, there is a risk that gears will be shifted by unintentional operation of the lever. Particularly on extremely rough roads, there is considerable potential for the operator's hand to inadvertently strike the lever, resulting in unintended shifting. Alternatives to the conventional lever type switch can be seen in the push-button arrangement of EP 0,566,025 or indeed the rotary switch of US 3996440 SUMMARY OF THE INVENTION. According to the present invention there is provided a bicycle transmission shift device in accordance with Claim 1. Preferred embodiments provide a shift device for a bicycle whereby shifting modes and the like are reliably switched by the operator at a location that is readily at hand, with less potential for accidental switching. In one embodiment of the present invention, a bicycle shift device includes a base member adapted to be mounted to a structural member of a bicycle, a dial rotatably mounted to the base member, a detent mechanism operatively associated with the dial for providing a detenting force to the dial at a plurality of rotational positions of the dial, and a first electromagnetic switching member operated by the dial for selectively electromagnetically communicating with a second electromagnetic switching member when the dial is positioned at each of the plurality of rotational positions. The switch may provide electromagnetic signals for controlling a plurality of bicycle transmission shift modes. A button and/or display may be disposed in proximity to the dial to allow the rider to control the bicycle transmission and to view the status of the selected gears, respectively. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a particular embodiment of a bicycle control device according to the invention mounted to a handlebar; Figure 2 is a view taken along line II-II in Figure 3; and Figure 3 is a cross sectional view of a particular embodiment of the dial and electrical contacts used in the bicycle control device shown in Figure 1. DETAILED DESCRIPTION OF THE EMBODIMENTS Figure 1 is a perspective view of a particular embodiment of a bicycle control device according to the invention mounted to a handlebar 8. As shown in Figure 1, a switch 1 is provided at a location adjacent to the right hand grip 9 of the bicycle handlebar 8. The switch 1 is provided with a generally circular rotatable rotating dial 2. The bottom of the rotating dial 2 can be rotated by the thumb of the right hand to switch positions. The outer peripheral edge of the rotating dial 2 has a slight texture to enhance friction force. The switching positions of the rotating dial 2 include a manual shift mode M, a first automatic shift mode A1, a second automatic shift mode A2, and a park mode P. Each mode letter should line up with the downward facing triangle mark at the top of the switch 1. A clicking sensation produced by a detent mechanism described below is produced at each switch position, allowing switching operations to be confirmed. No automatic shifting is performed in manual shift mode M. Instead, manual shifting is managed with an up shift button 4 and a down shift button 5. The first automatic shift mode A1 is for automatic shifting on flat terrain. The shift timing is calculated on the basis of detected data such as the bicycle speed and the torque applied to the crank spindle, and the shifting operations are performed automatically by an electric motor, actuator, or the like. Shifting can also be done manually at the same time by operating the up shift button 4 and down shift button 5. The second automatic shift mode A2 is for automatic shifting on uphill terrain. In this mode, the shift operations shift to a lower speed side than the first automatic shift mode Al. Park mode P locks and prevents the drive wheel from rotating. The bicycle can be parked in a stable manner, even when parked on inclined terrain or sloped roads, because the drive wheel is locked. While the bicycle is running, that is, while the drive wheel is turning, a safety function prevents the drive wheel from becoming locked if the rotating dial 2 should inadvertently be set to park mode P. The switch 1 is provided with a display means 3. The shift position of the front change gear device is displayed on the left side of the display means 3, and the shift position of the rear change gear device is displayed on the right side. The current shift state can be seen at a glance on the display means 3. Liquid crystal display panels, light-emitting diodes, and the like can be used as the display means 3. Figures 2 and 3 depict the internal structure of the switch 1. The rotating dial 2 and a brush platform 21 are locked by a screw and rotate together. A first electromagnetic switching member in the form of a brush 22 consisting of a conductive material is fixed to the brush platform 21, and an electrical connection with a second electromagnetic switching member in the form of an electrical contact provided on a base plate 13. The first and second electromagnetic switching members selectively communicate according to the rotating position of the rotating dial 2. An elastic convex component 23 is provided on one side of the brush platform 21. The brush platform 21 and the elastic convex component 23 are integrally formed of resin. In the top cover 11, at positions facing the elastic convex component 23, concave components 12 are provided in a plurality of locations corresponding to the plurality of switching positions of the rotating dial 2. The elastic convex component 23 fits into a concave component 12, thus forming the detent mechanism which produces a detenting force to the rotating dial 2. The detenting force guides the rotating dial 2 into the various switching positions and ensures reliable switching operations. Since switching operations are effected by the rotating dial as described above, there are no protruding parts such as levers, thus reducing the potential for unintended operation of the control device While the above is a description of various embodiments of the present invention, further modifications may be employed without departing from the scope of the present invention. For example, the size, shape, location or orientation of the various components may be changed as desired. The functions of one element may be performed by two, and vice versa. In the aforementioned embodiment, the switch is used to switch shift modes, but it can also be used for other switching operations such as turning a light on and off, or switching the modes of a bicycle display device. The switch display means can be used for displays other than the shift position, such as the running speed, distance travelled, or the like. In such cases, a display switch button that switches the display on the display means should be provided. Thus, the scope of the invention should not be limited by the specific structures disclosed. Instead, the true scope of the invention should be determined by the following claims.

Claims: A bicycle transmission shift device comprising: a base member (1) adapted to be mounted to a structural member of a bicycle; a dial (2) rotatably mounted to the base member (1); a detent mechanism operatively associated with the dial (2) for providing a detenting force to the dial (2) at a plurality of rotational positions of the dial (2); and a first electromagnetic switching member (22) operated by the dial (2) for selectively electromagnetically communicating with a second electromagnetic switching member when the dial (2) is positioned at each of the plurality of rotational positions, characterised in that the device further comprises: a cover (11) having a plurality of concave components (12) formed on an inner peripheral surface thereof; an elastic convex component (23) that rotates with the dial (2) for selectively engaging the plurality of concave components (12); and wherein the plurality of concave components (12) and the elastic convex component (23) form the detent mechanism. The device according to claim 1 wherein the dial (2) has four rotational positions, said positions corresponding to a manual operation shift mode, a first and a second automatic shift mode, and a park mode. The device according to either Claim 1 or Claim 2, wherein the device further comprises: a manually operated button (4,5) disposed in proximity to the dial (2). The device according to any preceding claim further comprising: display means (3) disposed in proximity to the dial (2) for displaying alphanumeric information. The device according to claim 4 wherein the display means (3) comprises an electrical display. The device according to any preceding claim wherein the first electromagnetic switching member (22) comprises a conductive brush that rotates with the dial (2). The device according to any preceding claim wherein the dial (2) is disposed on a first side of the cover (11) and the elastic convex component (23) is disposed on an opposite second side of the cover (11). A handlebar of a bicycle, wherein the device according to any preceding claim is mounted to the handlebar (8) in proximity to a hand grip (9) of said handlebar (8).

Inventors: ABE TAKEO, ABE, TAKEO
Applicants: SHIMANO KK, SHIMANO INC.
Application year: 1997
Main classification: B62M25
IPC codes: B62K23, B62M25