Bicycle speed control apparatus

A speed control apparatus for a bicycle includes a support shaft fixed to a bracket mounted on a handlebar; a first control lever pivotable about the support shaft and retainable in position after pulling a change speed wire to effect a change speed operation, the first control lever being returned to a pull starting position after the change speed operation; and a second control lever pivotable about the support shaft for releasing the change speed wire to effect a change speed operation, the second control lever being returned to a release starting position after the change speed operation. For improved operability of the apparatus, the first and second control levers are operable in opposite directions, with respective control portions of the levers movable close to each other when the levers are operated.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a speed control apparatus having a 
supporting device; a first control member pivotable about the supporting 
device and retainable in position after pulling a change speed wire to 
effect a change speed operation, the first control member being returned 
to a pull starting position after the change speed operation; a second 
control member pivotable about the supporting device for releasing the 
change speed wire to effect a change speed operation, the second control 
member being returned to a release starting position after the change 
speed operation; a first control portion formed on the first control 
member; and a second control portion formed on the second control member. 
2. Description of the Related Art 
A bicycle speed control apparatus as noted above is disclosed in U.S. Pat. 
No. 5,012,692, for example. This prior control apparatus includes a shift 
lever acting as the first control member, and a release lever acting as 
the second control member, which are operable in the same direction to 
wind and unwind a change speed wire. The shift lever is operated to wind 
the wire, and the release lever to unwind the wire. 
In the above construction, the shift lever returns to home position after 
each shifting operation. This feature provides the advantage of allowing 
the shift lever to be operated within an optimal stroke range to 
facilitate control even when the shift lever is operated to provide a 
speed many stages away from the home position. That is, the shift lever is 
shifted back and forth plural times to effect change speed in the wire 
winding direction. When effecting change speed in the wire unwinding 
direction, the release lever is operated to cancel action of a position 
retaining device. 
However, since the two levers are operable in the same direction according 
to the above prior construction, the cyclist could easily operate the 
wrong lever in a change speed operation. As a result, there is not a 
little chance of effecting change speed in the wrong direction. 
Furthermore, this type of speed control apparatus may be disposed adjacent 
a grip of a handlebar. In such a case, the two levers usually are operated 
with a thumb. Generally, there is only one position that is optimal for 
lever operation and, where the two levers are provided, one of the levers 
tends to be very difficult to operate. 
SUMMARY OF THE INVENTION 
The object of the present invention is to provide a bicycle speed control 
apparatus which facilitates operation of the first control member without 
an error with respect to a change speed direction. 
The above object is fulfilled, according to the present invention, by a 
bicycle speed control apparatus in which the first control member and the 
second control member are operable in opposite directions, the first 
control portion and the second control portion being movable close to each 
other circumferentially of the supporting device. 
According to this control apparatus, the first and second control members 
are operable in opposite directions, with the respective control portions 
thereof movable close to each other circumferentially of the supporting 
device. For example, the two control members may be operated separately 
with a thumb and a first finger. This reduces the possibility of operating 
the wrong lever, to assure a reliable change speed operation. 
By determining home positions of the two levers in a way to facilitate 
operation, for example, this construction allows the cyclist to operate 
the levers in the opposite directions without confusion between the first 
and second control portions of the levers. This characterizing feature of 
the present invention, thus, assures a reliable change speed operation, 
and greatly improves operability of the bicycle speed control apparatus. 
Other features and advantages of the present invention will be apparent 
from the description of the preferred embodiment to be had with reference 
to the drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
As shown in FIGS. 1 and 2, a bicycle speed control apparatus embodying the 
present invention is secured to a bracket B of a brake lever BL disposed 
below a handlebar H and adjacent a grip G of a mountain bike. FIG. 1 is a 
bottom view showing a region adjacent the grip G, and FIG. 2 is a view 
seen from a proximal end of the grip G. In FIGS. 1 and 2, a cyclist's hand 
is shown in phantom lines. 
This apparatus includes a shift lever 4 acting as a first control member, 
and a release lever 7 acting as a second control member. These levers 4 
and 7 are pivotally connected to a support shaft (which will be described 
later) under the handlebar H to be operable in opposite directions. The 
two levers 4 and 7 have home positions and strokes determined such that a 
first control portion 4A of the shift lever 4 and a second control portion 
7A of the release lever 7 are close to each other when the levers 4 and 7 
are at respective shift ends (FIG. 2). In the illustrated example, the 
shift lever 4 is operable by the thumb of the hand holding the grip G, 
while the release lever 7 is operable by the first finger of the same 
hand. This arrangement allows a brake lever BL and the levers 4 and 7 of 
the speed control apparatus to be operated reliably and efficiently with 
the hand holding the grip G. In FIG. 1, reference I denotes a change speed 
wire extending from a gear change device such as a front derailleur not 
shown. Reference O denotes an outer sleeve surrounding the change speed 
wire. Reference 1' denotes a stationary case, and reference 1a' a bearing 
for the outer sleeve. 
Details of the speed control apparatus will be described next. 
FIG. 3 is a view in vertical section through a support shaft 11 of this 
apparatus, which is shown upside down. The speed control apparatus is 
secured to the bracket B through a screw portion shown in the bottom of 
FIG. 3. FIGS. 4 and 5 are a section taken on line 4--4 of FIG. 3, showing 
the apparatus in a wire winding state and a wire unwinding state, 
respectively. 
This speed control apparatus includes, as main components thereof, a 
stationary section 1 secured to the bracket B (including the support shaft 
11, a retainer sleeve 12 and a fixed plate 14), a takeup reel 2 rotatable 
around the support shaft 11, a position retaining device P provided 
between the retainer sleeve 12 and takeup reel 2, a retention canceling 
device R for canceling action of the position retaining device P, the 
shift lever 4 and the release lever 7. 
The constructions of the support shaft 11 and takeup reel 2 will be 
described first. 
As shown in FIG. 3, the support shaft 11 extending downwardly from and 
perpendicular to the handlebar H, and the takeup reel 2 is rotatably 
supported on the support shaft 11 for winding up the change speed wire I. 
The takeup reel 2 includes a wire winding section 22a and a wire engaging 
section 22b formed peripherally thereof. The takeup reel 2 is urged in a 
wire unwinding direction (indicated by an arrow A in FIGS. 4 and 5) by a 
return spring 20. 
As shown in FIGS. 3 through 5, the takeup reel 2 further includes a 
plurality of feed teeth 21 defined on an outer peripheral surface thereof, 
and a plurality of first position retaining teeth 31 and a plurality of 
second position retaining teeth 61 defined on inner peripheral surfaces 
thereof. 
The support shaft 11 carries the retainer sleeve 12 mounted not to be 
rotatable relative thereto. The retainer sleeve 12 includes a first 
position retaining pawl 32 and a second position retaining pawl 62 
supported, to be pivotable relative to the retainer sleeve 12, on pawl 
shafts 35 and 65 extending substantially parallel to the support shaft 11. 
The first position retaining pawl 32 is urged by a first spring 33 toward 
the first position retaining teeth 31. The second position retaining pawl 
62 is urged by a second spring 63 away from the second position retaining 
teeth 61. 
The first position retaining teeth 31 and first position retaining pawl 32 
constitute a first rotation stopper P1 having a one-way transmission 
function to limit rotation in the wire unwinding direction and allow 
rotation in the wire winding direction of the takeup reel 2 relative to 
the stationary section 1. The second position retaining teeth 61 and 
second position retaining pawl 62 constitute a second rotation stopper P2 
to limit rotation in the wire winding direction of the takeup reel 2 
relative to the stationary section 1. The first rotation stopper P1 and 
second rotation stopper P2 are referred to herein as the position 
retaining device P. 
The relations of the shift lever 4 and release lever 7 with the support 
shaft 11 and retainer sleeve 12 will be described next. 
The shift lever 4 is pivotably supported adjacent one end (an upper region 
in FIG. 3) of the support shaft 11, and urged in the wire unwinding 
direction by a shift lever spring 5. The release lever 7 is pivotably 
supported adjacent the other end (a lower region in FIG. 3) of the support 
shaft 11, and urged in the wire winding direction by a release lever 
spring 7a. The shift lever 4 has a home position or wire pull starting 
position set to a position in which a contact portion 43 formed on the 
shift lever 4 contacts a setter 13 projecting from an intermediate 
position of the support shaft 11. The release lever 7 has a home position 
or release starting position set to a position in which a contact portion 
7b formed on the release lever 7 contacts a setter 1a projecting from the 
stationary section 1. 
Further, the shift lever 4 includes a feed mechanism for engaging the feed 
teeth 21 defined peripherally of the takeup reel 2 to transmit to the 
takeup reel 2 an operating force of the shift lever 4 acting in the wire 
winding direction. The feed mechanism includes a feed pawl 41 pivoted to 
the shift lever 4, and a spring 42 for urging the feed pawl 41 toward the 
feed teeth 21. The feed pawl 41 and feed teeth 21 have such an arrangement 
and shapes as to perform a one-way transmission function to transmit 
pivotal movement only for rotating the take up reel 2 in the winding 
direction. This mechanism provided between the shift lever 4 and takeup 
reel 2 is also referred to herein as a one-way transmission device W. The 
feed pawl 41 includes a projection 44 extending upward therefrom. When the 
shift lever 4 is in the home position, this projection 44 rides on a 
stationary cam 45 formed peripherally of the fixed plate 14 mounted on the 
support shaft 11 not to be rotatable relative thereto. In this way, the 
one-way transmission device W is disengageable only when the shift lever 4 
is in the home position. 
The relations between the release lever 7 and the above components will be 
described next. As shown in FIGS. 4 and 5, a first and a second cam 
devices C1 and C2 are provided between the release lever 7 and the first 
and second position retaining pawls 32 and 62. These cam devices include a 
first and a second cams 71 and 72 acting as drive elements and extending 
from proximal positions of the release lever 7 axially of the support 
shaft 11, and a first and a second cam followers 34 and 64 acting as 
driven elements and extending from upper surfaces of the first and second 
position retaining pawls 32 and 62 axially of the support shaft 11, 
respectively. With pivotal movement of the release lever 7, the second cam 
device C2 first pushes the second position retaining pawl 62 to a position 
engageable with the second position retaining teeth 61, and thereafter 
disengages the first position retaining pawl 32 from the first position 
retaining teeth 31. 
The cam devices C1 and C2 are operable to engage and disengage the first 
and second rotation stoppers P1 and P2, and are collectively referred to 
as the retention canceling device R which acts on the position retaining 
device P. Thus, the takeup reel 2 is retained in a rotational position (a 
position of rotation around the support shaft 11) by the position 
retaining device P, and released from that rotational position by the 
retention canceling device R. Rotation in the wire unwinding direction 
(indicated by an arrow A in FIGS. 4 and 5) of the takeup reel 2 after the 
release is limited to a predetermined amount by a positional relationship 
between the first rotation stopper P1 and second rotation stopper P2 
(relationship in pitch phase of the teeth). The position of the retention 
canceling device R shown in FIG. 4 is referred to herein as a first 
position, and the position thereof shown in FIG. 5 as a second position. 
The way in which the change speed apparatus constructed as above operates 
will be described next. 
As shown in FIGS. 1 and 2, the control portion 4A of the shift lever 4 is 
pressed in X direction with the thumb of the hand holding the grip G of 
the handlebar H. That is, the shift lever 4 is turned clockwise from the 
position shown in FIG. 4 (in X direction) to wind the wire. Then, the 
projection 44 of the one-way transmission device W moves below (that is, 
in the drawing) the stationary cam 45, and slips off the cam 45. As a 
result, the feed pawl 41 is turned in Z direction in FIG. 4, into 
engagement with the feed teeth 21. The feed pawl 41 rotates the takeup 
reel 2 in the winding direction (referenced B in the drawing), with the 
first position retaining pawl 32 disengaged from the first position 
retaining teeth 31, to pull the change speed wire. 
A first speed is provided when the shift lever 4 is turned in the winding 
direction by a stroke corresponding to one pitch of the position retaining 
teeth 31. A second speed is provided when the shift lever 4 is turned in 
the same direction by a stroke corresponding to two pitches of the teeth 
31. A change speed shift in this direction is referred to as a positive 
change speed operation. A single operation with the thumb may provide up 
to a third speed. For a fourth or higher speed, the shift lever 4 is 
returned to the home position once, and turned again in the winding 
direction. When a desired speed is achieved, the first position retaining 
pawl 32 engages the first position retaining teeth 31 (the first position 
retaining pawl 32 is constantly urged to the engaging position since the 
release lever 7 is in the position shown in FIG. 4, with the first cam 71 
remaining inoperative), thereby preventing the takeup reel 2 from rotating 
in the unwinding direction. In this way, the state for providing a desired 
speed is maintained reliably. When the shift lever 4 is released 
thereafter, the shift lever 4 returns to the home position under the force 
of the shift lever spring 5 (counterclockwise in A direction in FIG. 4). 
The shift lever 4 stops at the home position by the contact between the 
contact portion 43 and setter 13, to be ready for a next operation. At 
this time, the projection 44 rides on the stationary cam 45 to disengage 
the feed pawl 41 from the feed teeth 21. 
Where five to six speeds are available, the above construction allows a 
change to be made easily from a smaller gear to a larger gear by pushing 
the shift lever 4 twice in the winding direction with the thumb. 
To effect negative change speed which is opposite of the foregoing change 
shift, i.e. to change the chain from a larger gear to a smaller gear, the 
control portion 7A of the release lever 7 in the home position is pressed 
in Y direction with the first finger of the hand holding the grip G of the 
handlebar H, as shown in FIGS. 1 and 2. That is, the release lever 7 is 
turned counterclockwise from the position shown in FIG. 4 (in Y 
direction), which is opposite to the direction in which the shift lever 4 
is turned. As a result, the second position retaining pawl 62 is pressed 
toward the second position retaining teeth 61, with a tip end of the pawl 
62 entering a space between adjacent teeth 61. Thereafter the first 
position retaining pawl 32 is disengaged from the first position retaining 
teeth 31 as shown in FIG. 5. At this time, the takeup reel 2 rotates 
counterclockwise (in A direction in FIGS. 4 and 5) by an amount 
corresponding to a space between the second position retaining pawl 62 and 
one of the second position retaining teeth 61, i.e. within one pitch of 
the first position retaining teeth 31. When the release lever 7 is 
released and allowed to pivot clockwise, the first position retaining pawl 
32 moves to a position for engaging the first position retaining teeth 31, 
and then the second cam 72 stops pressing the second position retaining 
pawl 62. As a result, the second position retaining pawl 62 disengages 
from the second position retaining teeth 61, and the first position 
retaining pawl 32 engages a next one of the first position retaining teeth 
31. This engagement prevents the takeup reel 2 from rotating in the wire 
unwinding direction under the force of the return spring 20. Thus, a 
change speed state is provided reliably by a smaller gear corresponding to 
the newly engaged one of the first position retaining teeth 31. The 
returning release lever 7 stops at the home position by the contact 
between the contact portion 7b and setter 1a, to be ready for a next 
operation. 
The first and second control portions 4A and 7A of the levers may be 
movable to any positions relative to each other. As shown in 
two-dot-and-dash lines in FIG. 2, the first control portion 4A is close to 
the first finger and the second control portion 7A close to the thumb when 
at the respective shift ends. 
The foregoing embodiment may be modified in various ways as follows: 
(A) As shown in FIGS. 6 and 7, the release lever 7 may have a second 
control portion 7A disposed adjacent a proximal end of the brake lever BL. 
This will expedite operation of the release lever 7 by allowing a finger 
to be slid from the brake lever BL to the release lever 7. The second 
control portion 7A in this modification extends upward from an extreme end 
of the release lever 7 disposed below the brake lever BL, and is bent 
toward the grip G. Consequently, the second control portion 7A includes, 
for contact by the finger, not only a surface 7B perpendicular to the 
pivoting directions of the release lever 7 but an upper surface 7C lying 
along the pivoting directions. 
The second control portion 7A defines an inside surface bent in an inverted 
L-shape. The proximal end of the brake lever BL has an upper surface 
recessed as at B1, so that the proximal end fits inside the second control 
portion 7A when the release lever 7 is operated. Thus, the release lever 7 
is operable promptly within a small stroke for the large second control 
portion 7A, with only a small gap between the second control portion 7A 
and brake lever BL to avoid a finger or foreign articles becoming caught 
therein. Further, the brake lever BL and the second control portion 7A 
have a snug fitting appearance. 
The finger may be slid smoothly for a quick operation by forming the recess 
B1 to have such a depth that, as shown in FIG. 7, the upper surface of the 
brake lever BL is substantially flush with the upper surface 7C of the 
second control portion 7A. Further, the upper surface 7C of the second 
control portion 7A may include anti-slip knurls. 
(B) The shift lever 4 and release lever 7 may be arranged as desired. For 
example, the shift lever 4 may be operable with a first finger and the 
release lever 7 operable with a thumb. Either lever may be operable by a 
finger other than the first finger. 
(C) In the foregoing embodiment, the takeup reel 2 is rotatable in the 
unwinding direction by the force of the return spring 20. Instead, the 
takeup reel 2 may be arranged rotatable in the unwinding direction by a 
return spring included in the derailleur for acting on the change speed 
wire I. Thus, the return spring 20 provided between the takeup reel 2 and 
stationary section 1 is not absolutely necessary. 
(D) The shift lever 4 and release lever 7 may be mounted on separate shafts 
instead of the same common shaft The separate shafts supporting the levers 
4 and 7 need not be parallel to each other. 
(E) The first and second position retaining pawls 32 and 62 and the 
plurality of first and second position retaining teeth 31 and 61 may be 
reversed from the relations in the foregoing embodiment. 
(F) The position retaining device P, retention canceling device R and 
one-way transmission device W are not limited to what are shown in the 
foregoing embodiment, but may be modified in various ways based on the 
prior art. 
(G) The first and second control members need not be in the form of levers 
4 and 7 as in the foregoing embodiment. The grip itself may be used as the 
first and second control members. 
(H) The present invention is applicable for control of a rear derailleur 
and a front derailleur, and for control of a contained type change speed 
device besides the exposed type change speed device.