Bicycle shift control device

Abstract: A bicycle shift control device includes a takeup element (62)for pulling and releasing a shift control element, a first finger contact member (70), a second finger contact member (78), and an interconnecting member (86) that rotates around a rotational axis. The interconnecting member (86) interconnects the first finger contact member (70) and the second finger contacting member (78) so that the first finger contact member (70) and the second finger contact member (78) move in a same direction relative to the rotational axis. The first finger contact member (70) has a first finger contact surface (74) disposed on a first side of a plane, wherein the first finger contact member (70) moves toward the plane when the takeup element (62) moves in a pulling direction. Conversely, the first finger contact member (20) moves away from the plane when the takeup element (62) moves in a releasing direction. A second finger contact member (78) has a second finger contact surface (82) disposed on the first side of the plane, wherein the second finger contact member (78) moves away from the plane when the takeup element (62) moves in the pulling direction. Conversely, the second finger contact member (78) moves toward the plane when the takeup element (62) moves in the releasing direction. A first straight phantom line perpendicular to the first finger contact surface intersects a second straight phantom line perpendicular to the second finger contact surface. Other embodiments are disclosed, including embodiments featuring lever type controls in combination with winding drums, detents and cams and dial type controls.

Description: BACKGROUND OF THE INVENTION The present invention is directed to control devices for bicycle transmissions and, more particularly, to a shift control device that operates in the nature of a switch. Bicycle transmission shift control devices have many different forms. A simple transmission shift control device includes a rotatable lever extending from a wire winding drum such that rotation of the lever rotates the wire winding drum to pull and release a shift control wire. Sometimes a detent mechanism is incorporated into the shift control device so that the lever may be set in a plurality of predetermined positions to set the position of the shift control wire accordingly. More complicated lever-type shift control devices include multiple levers and ratchet mechanisms disposed between the levers and the wire winding drum such that rotation of one lever causes the wire to wind around the wire winding drum, and rotation of another lever causes the wire to unwind from the wire winding drum. Another type of shift control device includes an annular ring or sleeve that rotates around the bicycle handlebar. The ring or sleeve is directly or indirectly coupled to the shift control wire such that rotation of the ring or sleeve pulls and releases the shift control wire. In all of the above types of shift control devices, either the shift control device has a complicated structure, thus increasing the manufacturing cost and risk of malfunction of the device, or else the user must grab the lever or ring with at least the thumb and forefinger, sometimes accompanied with substantial movement of the hand, thus increasing the effort to operate the shift control device. Thus, there is a need for a shift control device that has a simple structure and can be operated with minimal effort. JP 58224879 describes an operating tool of a multistage variable speed changeover device for a bicycle. SUMMARY OF THE INVENTION The present invention is directed to a bicycle transmission shift control device that has a simple structure and can be operated with minimal effort. A bicycle shift control device comprises: a takeup element for pulling and releasing a shift control element; a first finger contact member having a first finger contact surface disposed on a first side of a plane, wherein the first finger contact member moves toward the plane when the takeup element moves in a pulling direction, and wherein the first finger contact member moves away from the plane when the takeup element moves in a releasing direction; and a second finger contact member having a second finger contact surface disposed on the first side of the plane, wherein the second finger contact member moves away from the plane when the takeup element moves in the pulling direction, and wherein the second finger contact member moves toward the plane when the takeup element moves in the releasing direction, wherein the takeup element is integrally formed with the first finger contact member and the second finger contact member, characterised in that: the takeup element is unbiased when the takeup element is disconnected from the shift control element. In certain embodiments of the present invention, an interconnecting member which rotates around a rotational axis may interconnect the first finger contact member and the second finger contacting member so that the first finger contact member and the second finger contact member move in a same direction relative to the rotational axis. In particular embodiments of the invention a first straight phantom line perpendicular to the first finger contact surface intersects a second straight phantom line perpendicular to the second finger contact surface. In the case of some embodiments of the invention, the first finger contact surface is disposed on a first side of the rotational axis, and the second finger contact surface is disposed on a second side of the rotational axis. Also, in the case of some embodiments, the first finger contact surface is disposed on a first side of the rotational axis, the second finger contact surface is disposed on a second side of the rotational axis, and a detent mechanism maintains the takeup element in two positions. A first of the two positions is a cable pulled position, and a second of the two positions is a cable released position. In other embodiments of the present invention, a first straight phantom line perpendicular to the first finger contact surface is substantially parallel to a second straight phantom line perpendicular to the second finger contact surface, wherein the first finger contact member moves along the first phantom line and the second finger contact member moves along the second phantom line. In still another embodiment of the present invention, a bicycle shift control device includes a takeup element for pulling and releasing a shift control element, only one finger contact lever for moving the takeup element, and a detent mechanism for maintaining the takeup element in only two positions. A first of the two positions is a cable pulled position, and a second of the two positions is a cable released position. In another embodiment of the present invention, a bicycle shift control device includes a base member, a rotatable dial coupled to the base member for rotation around a rotational axis, a finger contact projection extending from the rotatable dial in a direction of the rotational axis, and a shift element coupler disposed with the rotatable dial. In yet another embodiment of the present invention, a bicycle shift control device includes a base member having a base member axis and a rotatable member coupled to the base member coaxial with the base member axis, wherein the rotatable member rotates relative to the base member around the base member axis. A cam surface is disposed on at least one of the base member and the rotatable member so that the rotatable member moves in a direction of the base member axis when the rotatable member rotates relative to the base member. A finger contact projection extends from the rotatable member in a direction radially outwardly from the base member axis, and a shift element coupler is disposed with the rotatable member so that the shift element coupler moves in the direction of the base member axis when the rotatable member rotates relative to the base member. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an oblique view of a first embodiment of a shift control device according to the present invention; Fig. 2 is a cut away view showing how a control cable is connected to the shift control device; Fig. 3 is a cut away view showing a detent mechanism for the shift control device; Fig. 4 is an oblique view of a second embodiment of a shift control device according to the present invention; Fig. 5 is an oblique view of a third embodiment of a shift control device according to the present invention; DETAILED DESCRIPTION OF THE EMBODIMENTS Fig. 1 is an oblique view of a first embodiment of a shift control device 10 according to the present invention mounted to a bicycle handlebar 12; Fig. 2 is a cut away view showing how an inner wire 14 of a Bowden-type control cable 46 is connected-to shift control device 10, and Fig. 3 is a cut away view showing a detent mechanism 18 for shift control device 10. As shown in Figs. 1-3, shift control device 10 is mounted adjacent to a brake control device 22 having a brake control lever 26 pivotably connected to a brake control device housing 30 for operating a Bowden-type brake control cable 32 in a well known manner. Brake control device housing 30 includes an attachment band 34 that substantially encircles handlebar 12 for mounting brake control device 22 to handlebar 12 inward of a grip portion 36 of handlebar 12. More specifically, a mounting bolt 38 extends through an opening (not shown) in a mounting ear 42 and screws into a threaded opening (not shown) in an opposed mounting ear 46 for drawing mounting ears 42 and 44 toward each other to tighten attachment band 34 around handlebar 12. Attachment band 34 extends along a handlebar axis H, wherein handlebar axis H is centered within attachment band 34. In this embodiment, shift control device 10 is used to operate a Bowden-type control cable 46 wherein a shift control element such as inner wire 14 slides within an outer casing 48. Shift control device 10 includes a generally rectangular housing 50 that is attached to handlebar 12 though an attachment band 54 that has the same structure as attachment band 34 (i.e., two mounting ears tightened by a mounting bolt, not shown). A conventional cable adjusting barrel 58 screws into the side of housing 50 and terminates outer casing 48 of control cable 46 in a well known manner. A takeup element 62 (Fig. 2) having a cable coupling bore 64 and a winding surface 66 is disposed in housing 50. Cable coupling bore 64 engages a conventional cable end bead 65 of inner wire 14 for pulling and releasing inner wire 14. Inner wire 14 slightly winds and unwinds around winding surface 66 during the pulling and releasing operations. A first finger contact member 70 having a first finger contact surface 74 is disposed above and faces away from a plane P which, in this embodiment, contains an upper surface 75 of housing 50. A second finger contact member 78 having a second finger contact surface 82 also is disposed above and faces away from plane P. Of course, the plane P need not contain the upper surface 75 of housing 50, and first finger contact surface 74 and second finger contact surface 82 need not face away from plane P. An interconnecting member 86 is pivotably connected to housing 50 through a pivot shaft 90 so that interconnecting member 86 rotates around a rotational axis R that extends in a direction substantially perpendicular to attachment band 54 and handlebar axis H. As shown more clearly in Fig. 2, interconnecting member 86 interconnects first finger contact member 70, second finger contacting member 78 and takeup element 62 so that first finger contact member 70 and second finger contact member 78 are located on opposite sides of rotational axis R and move (i.e, pivot) in a same direction relative to rotational axis R. As a result, first finger contact member 70 moves toward plane P (from the position indicated in solid lines in Fig. 2 to the position shown in broken lines in Fig. 2) when takeup element 62 moves in a wire pulling direction, and first finger contact member 70 moves away from plane P when takeup element 62 moves in a wire releasing direction. Similarly, second finger contact member 78 moves away from plane P when takeup element 62 moves in the wire pulling direction, and second finger contact member 82 moves toward plane P when takeup element 62 moves in the wire releasing direction. To facilitate this operation, first finger contact member 70, second finger contact member 78, takeup element 62 and interconnecting member 65 in this embodiment are formed as one piece or at least integrally coupled together. In this embodiment, first finger contact surface 74 is inclined relative to second finger contact surface 82 such that a first straight phantom line L1 extending upwardly and perpendicularly away first finger contact surface 74 intersects a second straight phantom line L2 extending upwardly and perpendicularly away from second finger contact surface 82, regardless of the position in which shift control device 10 is viewed. The resulting structure operates like a rocker switch. While such a phantom line is readily determined from the flat finger contact surfaces 74 and 82 in this embodiment, such phantom lines also can be determined easily from embodiments with no flat finger contact surfaces by drawing the phantom line perpendicular to a line that is tangent to the finger contact surface at the point of contact between the phantom line and the finger contact surface. Also, in other embodiments the intersection of the phantom lines could be located downwardly away from the finger contact surfaces. Fig. 3 is a cut away view showing detent mechanism 18 for shift control device 10. In this embodiment, detent mechanism 18 maintains takeup element 62 in only two positions: the cable pulled position shown by broken lines in Fig. 2 and the cable released position shown by solid lines in Fig. 2. Detent mechanism 18 includes a first recess 92, a second recess 94 and a detent projection 98 formed on interconnecting member 86. A spring 102 is disposed in a recess 104 in housing 50 for pressing a detent member 108 against interconnecting member 86. Thus, takeup element 62 will be maintained in the cable pulled position when detent member 108 is disposed in first recess 92, and takeup element 62 will be maintained in the cable released position when detent member 108 is disposed in second recess 94. Unlike many prior art shift control devices, no biasing mechanism is provided to bias takeup element 62, first finger contact member 70 or second finger contact member 78 toward any particular position. Thus, when shift control device 10 is not connected to inner wire 14, takeup element 62, first finger contact member 70 and second finger contact member 78 are free to float in the range determined by the circumferential width of first recess 92 and second recess 94. As another feature of the present invention, we define a lever ratio LR = A/B, wherein A is the distance between the rotational axis R and a reference line RL perpendicular to first finger contact surface 74, the distance being measured perpendicular to reference line RL, and B is the distance between the rotational axis R and the inner wire 14. The location of RL is determined by adding 5 millimeters to the radius of curvature R1 (in millimeters) of the edge of first finger contact member 70. In this embodiment, R1 is one millimeter, so RL is located 6 millimeters from the edge of first finger contact member 70. Preferably, 0.8 < LR < 2. Fig. 4 is an oblique view of a shift control device 10' which represents a second embodiment of the present invention. This embodiment is constructed the same as shift control device 10 shown in Figs. 1-3 except where shown or noted. Accordingly, the same components are numbered the same. This shift control device 10' differs from shift control device 10 in that housing 50 extends radially outward from attachment band 54 and handlebar axis H, and rotational axis R is substantially parallel to handlebar axis H. Also, housing 50 includes a wire guide portion 120 with a cable guide surface 124 for changing the direction of inner wire 14 so that control cable 46 can extend substantially parallel to handlebar 12 in a well known manner. Fig. 5 is an oblique view of a shift control device 10" which represents a third embodiment of the present invention. This embodiment is constructed the same as shift control device 10 shown in Figs. 1-3 except where shown or noted. Accordingly, the same components are numbered the same. This shift control device 10" differs from shift control device 10 in that a lever 140 that is integrally formed as one piece with interconnecting member 86, first finger contact member 70 and second finger contact member 74 extends outwardly from plane P between first finger contact surface 78 and second finger contact surface 82. Thus, shift control device 10" can operate like a rocker switch by pressing first finger contact surface 78 or second finger contact surface 82. Alternatively, shift control device 10" can operate like a toggle switch by moving lever 140. 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 as defined by the appended claims. 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. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such feature(s). Thus, the scope of the invention should not be limited by the specific structures disclosed or the apparent initial focus on a particular structure or feature.

Claims: A bicycle shift control device (10, 10', 10") comprising: a takeup element (62,212) for pulling and releasing a shift control element (14); a first finger contact member (70,216) having a first finger contact surface (74,220) disposed on a first side of a plane, wherein the first finger contact member (70,216) moves toward the plane when the takeup element (62,212) moves in a pulling direction, and wherein the first finger contact member (70,216) moves away from the plane when the takeup element (62,212) moves in a releasing direction; and a second finger contact member (78,224) having a second finger contact surface (82,228) disposed on the first side of the plane, wherein the second finger contact member (78,224) moves away from the plane when the takeup element (62,212) moves in the pulling direction, and wherein the second finger contact member (78,224) moves toward the plane when the takeup element (62,212) moves in the releasing direction, wherein the takeup element (62,212) is integrally formed with the first finger contact member (70,216) and the second finger contact member (78,224), characterised in that : the takeup element (62,212) is unbiased when the takeup element (62,212) is disconnected from the shift control element (14). The device according to claim 1, further including an interconnecting member (86) that rotates around a rotational axis, wherein the interconnecting member (86) interconnects the first finger contact member (70) and the second finger contact member (78) so that the first finger contact member (70) and the second finger contact member (78) move in a same direction relative to the rotational axis. The device according to claim 2 wherein a first straight phantom line perpendicular to the first finger contact surface (74) intersects a second straight phantom line perpendicular to the second finger contact surface (82). The device according to claim 3 wherein the first straight phantom line extends away from the plane, and wherein the second straight phantom line extends away from the plane. The device according to any one of claims 2 to 4 wherein the first finger contact member (70) is one piece with the second finger contact member (78). The device according to any one of claims 2 to 5, wherein the first finger contact surface (74) has a first flat portion, wherein the second finger contact surface (82) has a second flat portion, and wherein the first flat portion is inclined relative to the second flat portion. The device according to any one of claims 2 to 6 wherein the first finger contact member (70) and the second finger contact member (78) pivot around the rotational axis. The device according to any one of claims 2 to 7 wherein the first finger contact surface (74) is disposed on a first side of the rotational axis and wherein the second finger contact surface (82) is disposed on a second side of the rotational axis. The device according to any preceding claim wherein the takeup element (62), the first finger contact member (70) and the second finger contact member (78) are one piece. The device according to any preceding claim further comprising a detent mechanism (18) for maintaining the takeup element (62) in one of a cable pulled position and a cable released position. The device according to any preceding claim wherein the first finger contact surface (78) and the second finger contact surface (82) face away from the plane. The device according to any preceding claim wherein the takeup element (62) includes a cable winding surface. The device according to any preceding claim further comprising a lever (140) extending away from the plane at a location between the first finger contact surface (74) and the second finger contact surface (82). The device according to any preceding claim wherein a lever ratio of the shift control device, which is the ratio of a distance between a rotational axis and a reference line perpendicular to the first finger contact surface (74) and a distance between the rotational axis and an inner wire (14) of a control cable (32) is less than 2.0. The device according to claim 1: wherein a first straight phantom line perpendicular to the first finger contact surface (220) is substantially parallel to a second straight phantom line perpendicular to the second finger contact surface (228); wherein the first finger contact member (216) moves along the first phantom line; and wherein the second finger contact member (224) moves along the second phantom line. The device according to claim 15 further comprising an interconnecting member (244) coupled between the first finger contact member (216) and the second finger contact member (224). The device according to claim 16 wherein the interconnecting member (244) comprises an interconnecting lever having a first end (245) coupled to the first finger contact member (216) and a second end (246) coupled to the second finger contact member (224). The device according to claim 17 wherein the interconnecting lever (244) pivots around a pivot axis disposed between the first end (245) and the second end (246). The device according to claim 18 wherein the pivot axis is located closer to one of the first end (245) and the second end (246) than the other one of the first end (245) and the second end (246). The device according to any one of claims 15 to 19, further comprising a gear rack (366) retained to one of the first finger contact member (216) and the second finger contact member (224), and wherein the takeup element (212) includes a plurality of gear teeth meshing with the gear rack (366). The device according to any one of claims 15 to 20 wherein the takeup element (212) rotates in response to movement of the first finger contact member (216) and the second finger contact member (224). The device according to any one of claims 15 to 21, wherein the first finger contact surface (220) and the second finger contact surface (228) face away from the plane. The device according to any one of claims 15 to 22, wherein the takeup element (212) includes a cable winding surface.

Inventors: OSE KENJI, OSE, KENJI
Applicants: SHIMANO KK, SHIMANO INC.
Application year: 2001
Main classification: B62M25
IPC codes: F16H61, B62M25, G05G1