U.S. patent application number 10/043632 was filed with the patent office on 2002-08-22 for automatic shifting control device for a bicycle.
Invention is credited to Horiuchi, Noriyuki.
Application Number | 20020113401 10/043632 |
Document ID | / |
Family ID | 24650893 |
Filed Date | 2002-08-22 |
United States Patent
Application |
20020113401 |
Kind Code |
A1 |
Horiuchi, Noriyuki |
August 22, 2002 |
Automatic shifting control device for a bicycle
Abstract
A bicycle features an automatically shifting transmission. The
shifting is controlled by a controller. The controller has a number
of ranges that comprise a subset of the available gear steps. The
operator of the bicycle can select an appropriate range and the
controller shifts gears within the range depending upon a preset
map of bicycle speeds and gear steps. The operator can select other
ranges as desired by upshifting or downshifting. The controller
also has at least one cruising mode that decreases the likelihood
of inadvertent shifting during operation of the bicycle at speeds
within a preset range of speeds. In addition, the controller has an
elapse mode that further reduces the number of available gear steps
in a range during resumed operation after slowing below a preset
speed or stopping.
Inventors: |
Horiuchi, Noriyuki; (Osaka,
JP) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
620 NEWPORT CENTER DRIVE
SIXTEENTH FLOOR
NEWPORT BEACH
CA
92660
US
|
Family ID: |
24650893 |
Appl. No.: |
10/043632 |
Filed: |
January 11, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10043632 |
Jan 11, 2002 |
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09660770 |
Sep 13, 2000 |
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Current U.S.
Class: |
280/261 ;
280/281.1 |
Current CPC
Class: |
B62M 9/123 20130101;
B62M 25/08 20130101; B62M 25/04 20130101; B62M 25/045 20130101;
B62M 9/122 20130101 |
Class at
Publication: |
280/261 ;
280/281.1 |
International
Class: |
B62M 001/02 |
Claims
What is claimed is:
1. A bicycle having a transmission capable of automatic shifting,
said bicycle comprising a frame assembly, a front wheel rotatably
connected to said frame assembly, a rear wheel rotatably connected
to said frame assembly, a crank connected to said frame assembly,
said transmission connecting said cranks and said rear wheel, said
transmission comprising a number of sprockets that define a set of
gears, a speed sensor being connected to at least one of said front
wheel and said rear wheel, a control unit electrically connected to
said speed sensor, a shift switch electrically connected to said
control unit, a shift actuator operably connected to said control
unit and to said transmission, said shift actuator being adapted to
initiate shifting of said transmission among said set of gears,
said control unit electrically connected to a memory, a shift table
being stored in said memory, said shift table comprising a first
subset of gears selected from said set of gears, a second subset of
gears selected from said set of gears, a third subset of gears
selected from said set of gears and shifting speeds corresponding
to each of said first subset of gears, said second subset of gears
and said third subset of gears such that said transmission can be
automatically shifted within a selected subset of gears at said
corresponding shift speed, said first subset of gears comprising a
number of gears that are included in said second subset of gears
and said second subset of gears comprising a number of gears that
are included in said third subset of gears, and said selected
subset being capable of selection by signals from said shift
switch.
2. The bicycle of claim 1, wherein said set of gears comprises a
rear sprocket set.
3. The bicycle of claim 1, wherein said set of gears consists of a
rear sprocket set.
4. The bicycle of claim 3, wherein said rear sprocket set comprises
eight gear steps.
5. The bicycle of claim 1, wherein said set of gears consists of
gears attached to said rear wheel.
6. The bicycle of claim 1, wherein said set of gears comprises at
least one sprocket located at said crank and a set of sprockets
located at said rear wheel.
7. The bicycle of claim 6, wherein said set of gears comprises a 34
tooth sprocket and a 36 tooth sprocket located at said crank.
8. The bicycle of claim 1, wherein said control unit comprises a
housing that is mounted to one of said frame assembly and a handle
bar assembly that is mounted to said frame assembly.
9. The bicycle of claim 8, wherein said control unit further
comprises a display screen.
10. The bicycle of claim 1, wherein said speed sensor is mounted
proximate said front wheel.
11. A bicycle having a transmission capable of automatic shifting,
said bicycle comprising a frame, a front wheel rotatably connected
to said frame, a rear wheel rotatably connected to said frame, a
crank connected to said frame, a transmission drivingly connecting
said crank and said rear wheel and comprising a set of gears, a
speed sensor connected to at least one of said front wheel and said
rear wheel, a control unit electrically connected to said speed
sensor, a first shift switch and a second shift switch electrically
connected to said control unit, a shift actuator operably connected
to said control unit and to said transmission and adapted to shift
said transmission through said set of gears, said control unit
comprising a memory of a first subset of gears and corresponding
shifting speeds, a second subset of gears and corresponding
shifting speeds, and a third subset of gears and shifting speeds,
said first subset of gears and said second subset of gears
overlapping and said second subset of gears and said third subset
of gears overlapping.
12. The bicycle of claim 1, wherein said first subset of gears
contains a lowest gear of said set of gears and said third subset
of gears contains a highest gear of said set of gears.
13. The bicycle of claim 1, wherein said control unit comprises a
display, a power switch and a mode switch.
14. The bicycle of claim 11, wherein said control unit comprises a
power source.
15. The bicycle of claim 1, wherein said second shift switch
selects among said first subset of gears, said second subset of
gears and said third subset of gears.
16. The bicycle of claim 1 further comprising a connector box
interposed between said control unit and said shift actuator.
17. The bicycle of claim 1, wherein said speed sensor is connected
to said front wheel.
18. The bicycle of claim 1, wherein set of gears of said
transmission comprises a first group of gears drivingly coupled to
said crank and a second group of gears drivingly coupled to said
rear wheel, said transmission further comprising a chain coupling
said first group of gears and said second group of gears, and said
bicycle further comprising a front derailleur mounted to said frame
and a rear derailleur mounted to said frame.
19. The bicycle of claim 18, wherein said shift actuator comprises
a front shift actuator coupled to said front derailleur and a rear
shift actuator coupled to said rear derailleur.
Description
RELATED APPLICATIONS
[0001] This application is a division of U.S. patent application
No. 09/660,770, filed on Sep. 13, 2000.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to automatically
shifting transmissions for bicycles. More specifically, the present
invention relates to strategies for controlling the shifting
patterns in such transmissions.
[0004] 2. Related Art
[0005] In recent years, bicycles have begun to incorporate
automatic transmissions. The automatic transmissions can be either
mechanical or electronic in configuration. In the mechanical type
transmissions, centrifugal forces are used to change between gears
of the transmission. In an electronic type transmission, certain
operating characteristics can be sensed and used to signal a
desired change between gears. Some of the electronic type
transmissions sense operating speed of the bicycle to indicate that
a gear change is desired.
[0006] The automatic transmissions can be used on bicycles
featuring increasing numbers of gear steps through which the
transmission can operate. For instance, in bicycles featuring a
chain drive with a front sprocket set and a rear sprocket set, the
rear sprocket set can comprise ten or more gear steps while the
front sprocket can comprise three or more gear steps. The increase
in numbers of available gear steps allows a rider to select an
appropriate gear combination for any particular riding condition.
In addition, when riding a manual transmission bicycle (or in a
manual mode), the rider can skip intermediate gears to provide a
comfortable shifting pattern.
SUMMARY OF THE INVENTION
[0007] The large number of available gears, however, causes
problems with automatic transmissions. As the rider rapidly
increases the speed of the bicycle, the automatic transmission may
begin stepping through the gears in rapid succession. It has been
found that rapid shifting can be aggravating to the rider. In
addition, the lower most gears may not be desired for ordinary use
by the rider. Moreover, due to the large number of available gears,
the transmission will change gears according to a schedule having
very small speed ranges between gear shifts. Thus, the rider may
experience shifting even though they are attempting to maintain a
steady pace.
[0008] Thus, an automatic transmission control system for a bicycle
is desired that allows the range of gears to be selected by the
rider. The system preferably automatically changes gears within the
transmission among a preset range of gears. The rider should be
able to change the preset range of gears as desired. The
transmission, therefore, will change gears less often and can be
adapted for particular riding conditions. As a result of having
less gear steps available, the speed ranges associated with each
gear step will be enlarged to decrease the likelihood of undesired
shifting. To further decrease the likelihood of such gear changes,
the system preferably is able to recalibrate the shifting schedule
after the rider has achieved a relatively steady pace. Finally, the
transmission preferably is able to detect a rapid deceleration and
accommodate the downshifting through the gears by reducing the
number of gears within the preset range.
[0009] Accordingly, one aspect of the present invention involves a
control arrangement for a bicycle transmission capable of automatic
shifting. The arrangement comprises a transmission having a first
set of gear steps and a shift controller that is adapted to move
the transmission between each of the first set of gear steps. A
control unit is electrically connected to the shift controller. The
control unit is adapted to selectively operate the shift controller
in an automatic mode using a second set of gear steps selected from
the first set of gear steps. The second set of gear steps comprises
at least one less gear step than the first set of gear steps. The
control unit automatically actuates the shift controller to move
the transmission between at least two steps of the second set of
gear steps depending upon a sensed operating speed of the
bicycle.
[0010] Another aspect of the present invention involves a method of
controlling shifting in a bicycle transmission capable of automatic
shifting. The method comprises sensing an operating speed of the
bicycle, monitoring a period of time between transmission shifts,
determining when a preset period of time between transmission
shifts has elapsed and recalibrating an upper speed value and a
lower speed value for a gear step currently in use.
[0011] A further aspect of the present invention involves another
method of controlling shifting in a bicycle transmission capable of
automatic shifting. The method comprises sensing an operating speed
of the bicycle, automatically changing gears within a first preset
range of gear steps depending upon the operating speed of the
bicycle, determining if the operating speed is rapidly reduced
below a first threshold operating speed, switching to a second
preset range of gear steps when the operating speed is rapidly
reduced below the first threshold operating speed, automatically
changing gears within the second preset range of gear steps
depending upon the operating speed of the bicycle, and the first
preset range of gear steps comprising more gear steps than the
second preset range of gear steps.
[0012] Another aspect of the present invention involves a method of
controlling shifting in a bicycle transmission capable of automatic
shifting. The method comprising selecting an automatic operating
mode, selecting a first preset range of gear steps from a plurality
of preset ranges of gear steps, and operating the bicycle
transmission among the selected preset range of gear steps.
[0013] A further aspect of the present invention involves a bicycle
having a transmission capable of automatic shifting. The bicycle
comprising a frame, a front wheel rotatably connected to the frame
and a rear wheel rotatably connected to the frame. A crank is
connected to the frame. A transmission drivingly connects the crank
and the rear wheel. A speed sensor is connected to at least one of
the front wheel and the rear wheel. A control unit is electrically
connected to the speed sensor. A first shift switch and a second
shift switch are electrically connected to the control unit. A
shift actuator is operably connected to the control unit and to the
transmission and is adapted to shift the transmission through a set
of gears. The control unit comprises a memory of a first selected
set of gears and corresponding shifting speeds, a second selected
set of gears and corresponding shifting speeds, and a third
selected set of gears and shifting speeds. The first selected set
of gears and the second selected set of gears overlap and the
second selected set of gears and the third selected set of gears
overlap.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] These and other features, aspects and advantages of the
present invention will now be described with reference to the
drawings of a preferred embodiment, which embodiment is intended to
illustrate and not to limit the invention, and in which
figures:
[0015] FIG. 1 is a side elevation view of a bicycle having an
automatic shifting control device arranged and configured in
accordance with the present invention;
[0016] FIG. 2 is an enlarged perspective view of a handlebar region
of the bicycle of FIG. 1;
[0017] FIG. 3 is a schematic diagram of an automatic shifting
control device having certain features, aspects and advantages in
accordance with the present invention;
[0018] FIG. 4 is a flow diagram for a cruising mode of operation of
the automatic shifting control device; and,
[0019] FIG. 5 is a flow diagram for an elapsed control mode of
operation of the automatic shifting control device.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE
INVENTION
[0020] With reference now to FIG. 1, a bicycle is illustrated
therein. The bicycle is identified by the reference numeral 10. The
illustrated bicycle 10 will provide an exemplary environment in
which the present invention can be used. Of course, there are many
other types of bicycles and other human-powered vehicles with which
certain features, aspects and advantages of the present invention
can be used. Accordingly, while the present control device and
system will be described in the context of the illustrated bicycle,
it should be understood that various features, aspects and
advantages of the present device and system also can be used in
other environments.
[0021] The illustrated bicycle 10 comprises a welded-up frame
assembly 12, such as those well-known in the art. A front fork and
handle bar assembly 14 is pivotally mounted to a forward portion of
the frame assembly 12. A front wheel 16 is rotatably supported
within the front fork and handle bar assembly 14. The front wheel
16 can be steered through a set of handle bars 18 in any suitable
manner.
[0022] With reference to FIG. 2, the handle bars 18 preferably are
mounted to the remainder of the front fork and handle bar assembly
14 at a handle bar stem 20. While the illustrated handle bars 18
are generally straight, other curved handle bars also can be used
with the present invention. For instance, the handle bars 18 can
bend upward and forward, upward and rearward, downward and forward
or downward and rearward.
[0023] A rear wheel 22 also is rotatably mounted to the frame
assembly 12. The rear wheel can be powered through a suitable
transmission 24 by power input through a set of pedals 26 mounted
to associated crank arms 28. The suitable transmission 24 can be a
chain drive or a shaft drive. The transmission should include a
change speed feature in which the transmission 24 can be shifted
through a variety of gear steps. Such transmissions are well known
in the art and can include external arrangements (i.e., sprockets)
and internal arrangements (i.e., internal gear hubs).
[0024] In the illustrated arrangement, a rear sprocket set 30 is
mounted to the rear wheel. The rear sprocket set 30 can include a
number of gear steps that are defined by varied tooth numbers. In
one configuration, the rear sprocket set 30 can include three gear
steps. In another configuration, the rear sprocket can include
eight gear steps and the tooth numbers can vary from 11 to 33. Any
number of gear steps can be used. The gear steps will be described
below in more detail. The illustrated arrangement also features a
front sprocket set 32. In some arrangements, a single front
sprocket can be used. In other arrangements, a dual front sprocket
can be used. A presently preferred arrangement includes a duel
front sprocket featuring 34 and 46 teeth. The front sprocket set 32
and the rear sprocket set 30 are connected with a chain 34 in the
illustrated arrangement.
[0025] Shifting of the illustrated transmission 24 is accomplished
using actuator controlled derailleurs. A rear shifting device 36 is
used to shift among the gear steps on the rear sprocket set 30 and
a front shifting device 38 is used to shift between the gear steps
on the front sprocket set 32. The shifting devices 36, 38 can
comprise a motorized actuator or a solenoid-type actuator. Both of
such devices 36, 38 are known by those of ordinary skill in the
art. The actuators move the associated derailleur from gear step to
gear step as desired. A position sensor can be associated with each
device 36, 38 to monitor the position of the derailleur. The
control of these actuators will be discussed in more detail
below.
[0026] The illustrated bicycle also features standard front brakes
and rear brakes. As is known, a brake lever 40 can be operated to
pull a wire of a bowden-wire type of cable 42. As the wire is
pulled, the brakes are applied. In the illustrated arrangement, a
clamping action about the front rim occurs at a front brake caliper
44. A similar arrangement also is used for the rear wheel wherein a
rear brake lever 46 is used to manipulate a cable 48 and a rear
brake caliper 50. As illustrated in FIG. 2, the levers 40, 46
preferably are mounted proximate hand grips 52 formed on the handle
bars 18.
[0027] With continued reference to FIG. 2, a control unit housing
54 is mounted to the bicycle 10. Preferably, the control unit
housing 54 is mounted to either the frame assembly 12 or the front
fork and handle bar assembly 14. In the illustrated arrangement,
the control unit housing 54 is mounted proximate the stem 20 and
the handlebars 18.
[0028] A number of components preferably are mounted within the
control unit housing 54. For instance, in the illustrated
arrangement, a display screen 56 is provided. The display screen 56
can be used to display various operating parameters of the bicycle
10 and the associated transmission 24. For instance, in some
arrangements, the display screen 56 can display which shifting mode
has been selected (i.e., automatic or manual), whether a cruising
mode has begun and other operating conditions. In other
arrangements, the display screen can provide visual confirmation of
speed, pedal torque or the like.
[0029] The illustrated control unit housing 54 also encases a
central processing unit (CPU) or other type of controller 58. The
controller 58 in the illustrated arrangement is electrically
connected to a variety of input devices and output devices. For
instance, the controller 58 is electrically connected to a speed
sensor 60 that is disposed to detect an operating speed of the
bicycle 10. In the illustrated arrangement, the speed sensor 60 is
mounted to the front fork assembly 14 proximate the front wheel 16;
however, other locations, such as proximate the rear wheel 18, for
example but without limitation, also can be used. The speed sensor
60 in the illustrated arrangement comprises an emitter and detector
or a magnet 62 and a detector 64. Other suitable arrangements also
can be used.
[0030] With reference to FIG. 2, the illustrated controller 58 also
can be electrically connected to a first shift switch 66 and a
second shift switch 68. While the illustrated arrangement features
a first shift switch 66 on a left side of the illustrated handle
bars 18 and a second shift switch 68 on a right side of the
illustrated handle bars 18, the positioning of the switches 66, 68
can be varied. For instance, the switches can be reversed, moved to
a different region of the handle bars 18 or moved to a different
region of the frame assembly 12 altogether. In the illustrated
arrangement, the switches 66, 68 are directly electrically
connected to the controller through a set of wires 70 (i.e., hard
wired), it is anticipated that other types of electrical
connections (i.e., infrared, radio waves, etc.) also can be
used.
[0031] With continued reference to FIG. 2, the illustrated switches
66, 68 each comprise a pair of contact pads 72, 74. The pair of
contact pads 72, 74 can be used to generate a first signal and a
second signal. In the illustrated arrangement, the first contact
pad 72 can be used to generate an up-shift signal while the second
contact pad 74 can be used to generate a down-shift signal. Of
course, these signals can be interchanged. Also, while the
illustrated arrangement uses a pair of contact pads 72, 74, other
arrangements can use three-position switches, toggle switches or
other suitable switches.
[0032] In the illustrated arrangement, the first shift switch 66 is
used to generate signals for the front shifting device 38.
Preferably, the front shifting device is controlled manually and
not automatically. Movement in the front shifting device 38 can be
used to select a higher range of gear steps or a lower range of
gear steps. Moreover, in the illustrated arrangement, the second
shift switch 68 is used to generate signals for the rear shifting
device 36. The second shift switch 68 can be used in conjunction
with either an automatic mode or a manual mode, as will be
described. The second shift switch can be used to step between gear
steps on the rear sprocket set 30. Additionally, as will be
described, the second shift switch 68 also can be used to step
between ranges in an automatic mode.
[0033] The illustrated controller 58 also is connected to a pair of
switches 76, 78 that are disposed on the housing 54 itself. The
first of the pair of switches is a power switch 76 in the
illustrated arrangement. The power switch 76 connects and
disconnects a power source 77 (i.e., a battery), which can be
mounted within the housing 54, to the controller 58 and/or the
actuators of the shifting devices 36, 38. The second of the pair of
switches is a mode switch 78 that can be used to select an
operational mode of the control system. In one arrangement, the
mode switch 78 can be used to select between automatic shifting and
manual shifting. The various modes of the present invention will be
discussed in detail below. The switches 76, 78 preferably are
electrically connected to the controller 58. Again, the connections
can be any suitable configuration and can include hard-wired and
non-hard-wired arrangements.
[0034] In the illustrated arrangement, the front and rear shifting
devices 36, 38 include a position detector (not shown) that outputs
a signal indicative of the location of the derailleur or chain 34
on the respective sprocket sets 30, 32. The signal is received by
the controller 58. Also, the controller 58 can be connected to the
display 56 in the illustrated arrangement.
[0035] Accordingly, the illustrated controller 58 receives input
signals from the speed sensor 60, the position detector (not
shown), the shift switches 66, 68, the power switch 76 and the mode
switch 78. The data is processed and output signals can be
generated that are output to the display 56, the rear shift device
36 and the front shift device 38. With reference to FIG. 1, a
connector box 80 is positioned between the controller 58 and the
two shifting devices 36, 38. In the illustrated arrangement, a
single wire 82 extends between the connector box 80 and the
controller 58. The single wire 82 can carry input data from the
position detector and output data from the controller 58.
[0036] The controller 58 also includes a memory device 84 of any
suitable type. In the illustrated arrangement, the memory device 84
stores a variety of data related to gear steps and operational
speeds. The memory device 84 can be read only or can be read-write
in some applications. The read-write type of memory device 84 can
be used to track various data, as desired by the operator. The
stored data related to gear steps and operation speeds can be in
tabular form and can include tables such as those that will be
discussed below.
[0037] The illustrated transmission features both automatic and
manual modes. In manual mode, the operator can select gears in a
manner well known to those of skill in the art. In automatic mode,
the operator can select ranges of gear steps in accordance with
certain features, aspects and advantages in accordance with the
present invention. In one arrangement, the ranges of gear steps
each comprise at least one gear step less than the total number of
available gear steps. Preferably, the total number of gear steps is
set by the number of gear steps available on a single sprocket set,
for instance, such that the resulting gear steps are all on a
single sprocket or gear set rather than by combining sprockets
(i.e., selecting ratios rather than gear steps) as would be done in
a synchronous transmission. This selection of gear steps from a
single sprocket or gear set results in an advantageously simple
construction and operation. Thus, each of the ranges desirably is a
subset of the total number of gear steps available. More desirably,
the selected gear steps in each of the ranges are contiguous.
[0038] With reference now to the following table, Table 1, an
exemplary control system will be described.
1TABLE 1 Shifting Speed 0-V1 V1-V2 V2-Vn-1 . . . Vn-1-Vn-2 Vn-2
Default Selection 2 3 4 . . . n-2 n-1 Upshift 3 4 5 . . . n-1 n
Downshift 2 3 4 . . . n-2 n-1 Downshift 1 2 3 . . . n-3 n-2 Upshift
2 3 4 . . . n-2 n-1 Upshift 3 4 5 . . . n-1 n Upshift 4 5 6 . . . n
n
[0039] As illustrated in Table 1, which can be stored in memory,
the transmission can include a number of gear steps. In the
illustrated arrangement, the transmission includes n gear steps. As
the speed of the bicycle increases and decreases, the selected gear
step changes. An operator of the bicycle, however, can select the
range of gears through which the bicycle transmission operates. For
instance, in the illustrated arrangement, the default selection
includes gear steps 2 through n-1. In such a selected range, as the
bicycle speed increases above V1, the gear step is shifted from 2
to 3. As the bicycle speed increases above V2, the gear step is
shifted from 3 to 4. Similarly, as the bicycle speed decreases
below V2, the gear step is shifted from 4 to 3.
[0040] One aspect of the present invention involves the ability to
select the operating range of gears. The ranges of gear steps
desirably include a number of gears that is at least one gear step
less than the fall range of available gear steps. For instance, in
one arrangement, each range of gear steps in a transmission of n
gear steps can include n-2 gear steps. In other arrangements, the
number of gears steps in any one range can be n-3 or n-4 gear
steps.
[0041] With continued reference to Table 1, the operator can
upshift and downshift, which, in the automatic mode, causes an
upshift or downshift between differing gear step ranges rather than
simply changing gears. The upshift or downshift can be initiated by
operating the second shift switch 68 in the illustrated
arrangement. For instance, during operation with a strong tailwind,
an operator can upshift to a higher gear step range by depressing
contact pad 72. As a result of the upshift, gear steps 3 through n
would be used rather than 2 through n-1. Of course, during uphill
operation, an operator may desire a lower range of gear steps.
Accordingly, the operator can downshift to a lower range by
depressing contact pad 74. The lower range (after two downshifts in
the illustrated arrangement of Table 1) would comprise gear steps 1
through n-2. The selection of the range can be performed
incrementally, such as that of the illustrated arrangement. Of
course, the arrangement also can be preset to allow jumps of two or
more ranges in either direction (i.e., double-upshifting or
double-downshifting).
[0042] It is anticipated that shifting also can be controlled
through a variety of other sensors. For instance, a manual movement
of the front shifting device 38 to a lower gearing may be used to
indicate that a downshift in gear step range is desired as well.
Accordingly, during automatic shifting mode, movement of the front
shifting device 38 to a lower gear can be used as a proxy for an
downshift and movement of the front shifting device 38 to a higher
gear can be used as a proxy for an upshift in the gear step
range.
[0043] Additionally, a slope sensor (not shown) can be electrically
connected to the controller 58. The slope sensor can be used to
initiate changes in gear step ranges. For instance, if the slope
sensor detects a slope greater than a first preset value, the gear
step range may be increased, and if the slope sensor detects a
slope less than a second preset value, the gear step range may be
decreased. Of course, the first preset value and the second preset
value can be the same value in some arrangements.
[0044] Moreover, a heart rate monitor or a driving torque sensor
can be used to control the selection of shifting ranges. For
instance, a target heart rate, such as 150 beats per minute, for
instance, can be used to select an appropriate gear range to
maintain the operator's heart rate within a target range. Also, the
driving torque sensor can be used to decrease the driving torque or
increase the driving torque by adjusting the range of gear steps
being used. Other sensors and operational controls can also be
used.
[0045] With reference to the following table, Table 2, a presently
preferred arrangement featuring 8 gear steps (i.e., a sixteen speed
transmission) is illustrated.
2TABLE 2 Shifting Speed 0-9 9-13 13-17 17-21 21-25 25- Default
Selection 2 3 4 5 6 7 Upshift 3 4 5 6 7 8 Downshift 2 3 4 5 6 7
Downshift 1 2 3 4 5 6 Upshift 2 3 4 5 6 7 Upshift 3 4 5 6 7 8
Upshift 4 5 6 7 8 8
[0046] The arrangement illustrated in Table 2 operates in the same
manner as the arrangement illustrated in Table 1. The default
selection can be any of the gear step ranges. In the illustrated
arrangement, shifting occurs at 9 km/hr, 13 km/hr, 17 km/hr, 21
km/hr and 25 km/hr. Thus, for the illustrated arrangement, 8 gear
steps have been reduced to a set of ranges features 6 gear steps.
The default selection in the illustrated arrangement includes gear
steps 2-7 which can be increased or decreased as desired by
upshifting or downshifting through the ranges. As the bicycle speed
increases above 9 km/hr, the rear shifting device changes the gear
step from 2 to 3. If the operator desires an upshift in ranges, the
rear shifting device changes the gear step from 3 to 4 while the
bicycle is being operated at a speed between 9 km/hr and 13 km/hr.
Shifting would continue within the selected range of gear steps
until a new range is selected. It should also be noted that while
the arrangement of Table 2 results in 6 gear steps being selected
from 8 gear steps, it is anticipated that other numbers of gear
steps also can be selected, such as 5 gear steps and 7 gear steps,
without limitation.
[0047] With reference now to the following table, Table 3, a set of
cruising mode strategies are illustrated. The illustrated cruising
mode strategies can be used in the control system configured and
arranged in accordance with certain features, aspects and
advantages of the present invention.
3TABLE 3 Front Rear Auto Mode Cruising 1 Cruising 2 Tooth Gear
Tooth Gear Min. Max. Min. Max. Min. Max. No. Step No. Ratio Speed
Speed Speed Speed Speed Speed 46 1 33 1.39 46 2 29 1.59 0 9 0 8 46
3 25 1.84 9 13 8 12 0 11 46 4 21 2.19 13 17 12 16 11 16 46 5 17
2.71 17 21 16 20 16 21 46 6 15 3.07 21 25 20 24 21 26 46 7 13 3.54
25 3 24 26 46 8 11 4.18 34 1 33 1.03 34 2 29 1.17 0 9 0 8 34 3 25
1.36 9 13 8 12 0 11 34 4 21 1.62 13 17 12 16 11 16 34 5 17 2 17 21
16 20 16 21 34 6 15 2.27 21 25 20 24 21 26 34 7 13 2.62 25 24 26 34
8 11 3.09
[0048] With reference now to Table 3, two cruising modes having
certain features, aspects and advantages of the present invention
will be discussed. The two cruising modes operate in generally the
same manner; however, recalibration of the speed ranges (i.e., max.
speed and min. speed) differs between the two cruising modes. Also,
it should be noted that cruising mode and automatic mode can be
operated regardless of the selected front sprocket.
[0049] With reference now to FIG. 4, a flow diagram is presented of
a al cruising mode which encompasses both of the cruising modes
depicted in Table 3. During operation of the bicycle in automatic
shifting mode, the speed of the bicycle is monitored (S-1). In the
illustrated arrangement, the monitoring of the speed is
substantially continuous. In some arrangements, sampling of the
speed can be performed at preset time intervals. In addition to the
speed being monitored, the time between subsequent shifts is also
monitored (S-2). While monitoring the speed and the time are shown
in separate blocks in FIG. 4, the two can be monitored
simultaneously.
[0050] The controller 58 then checks to see whether the time
between shifts has exceeded a preset time period (S-3). In the
illustrated arrangement, the preset period is approximately 10
seconds. Operation of the bicycle within a single gear step (i.e.,
between the minimum and maximum speeds for that gear step) can
automatically select operation of the bicycle in a cruise mode. The
cruise mode advantageously reduces the likelihood that the
transmission will automatically shift due to slight variations in
bicycle speed. Thus, if the time between shifts exceeds the preset
time period, the controller 58 recalibrates the minimum speed, the
maximum speed or both (S-4). Preferably, the range defined between
the minimum speed and the maximum speed is recentered or expanded
in manners that will be described below.
[0051] In the illustrated arrangement, a gear shift is used to
deactivate the cruise mode. It should be understood that the
automatic activation and deactivation can be replaced by manual
selection of a cruise mode in some arrangements. The automatic
activation and deactivation, however, results in an arrangement
that is more user friendly. In addition, deactivation can also be
triggered in other manners; however, in the illustrated
arrangement, the controller awaits a signal of a gear shift (S-5)
before deactivating the cruise mode. Upon deactivation, the
controller preferably resets the minimum speeds and the maximum
speeds to the preset default speeds (S-6).
[0052] With reference again to Table 3, two recalibration
techniques will be described in more detail. While two
recalibration techniques are described, other techniques also can
be used. In the first technique, which is shown in the table under
Cruising 1, the range is recentered. Specifically, an average speed
for a preset period of time is calculated. In the illustrated
arrangement, the preset period of time is the same as preset period
of time used to activate the cruising mode (i.e., 10 seconds). The
range is then divided in half and half of the range is subtracted
from the average speed and half of the range is added to the
average speed. This process results in the average speed being
substantially centered in the range. It is anticipated that the
range also can be readjusted in other manners by using less than
half of the range. In the illustrated arrangement of Table 3, if
the average speed while in gear step 4 was calculated as 14 km/hr.
then the range (i.e., 17 km/hr-13 km/hr=4 km/hr) is divided by 2
(i.e., 4 km/hr/2=2 km/hr) and the range is recentered about 14
km/hr. Thus, the minimum speed for gear step 4 would be 12 km/hr
and the maximum speed would be 16 km/hr rather than the default
speeds of 13 km/hr and 17 km/hr. Preferably, this recalibration
technique is repeated at the end of each preset period of time.
[0053] With continued reference to Table 3, in the second
recalibration technique, that shown in the table under Cruising 2,
the range between the minimum speed and the maximum speed is
expanded and the number of gear steps in the range in decreased. Of
course, in some arrangements, the number of gear steps will not be
altered. In the illustrated arrangement, assuming that the average
speed is 18 km/hr while in gear step 5, the range of speeds is
widened such that the range is 5 km/hr rather than the default 4
km/hr. Thus, the minimum speed is decreased to 16 km/hr and the
maximum speed remains 21 km/hr. This results in the average speed
of 18 km/hr being substantially centered within the range. In order
to better accommodate the expanding speed ranges, the number of
gear steps can be decreased. The illustrated arrangement can be
repeated; however, by expanding the ranges, the number of gear step
changes would be decreased and the likelihood of undesired shifting
is decreased. Thus, when operating in the Cruising 2 mode,
recalibration can be performed once or less often than when
operating in the Cruising 1 mode.
[0054] With reference now to Table 4 and FIG. 5, an elapse mode is
illustrated therein. The elapse mode can be used during rapid
deceleration. For instance, if the bicycle is operating in
automatic shifting mode at about 24 km/hr and the speed is rapidly
decreased below a threshold speed, then the transmission will be
rapidly downshifting through the gear steps in an attempt to change
with the bicycle speed. Moreover, if the bicycle comes to an abrupt
stop, then the transmission downshift will occurs while the
operator is trying to resume operation of the bicycle. Thus, the
elapse mode detects such a rapid slowing or stopping of the bicycle
and reduces the number of available gear steps. By reducing the
number of available gear steps, the transmission will not be
downshifting through as many gears and the operator will have
better control of the bicycle during resumed operation.
4TABLE 4 Front Rear Auto Mode Elapse Mode Auto Mode Tooth Gear
Tooth Gear Min. Max. Min. Max. Min. Max. No. Step No. Ratio Speed
Speed Speed Speed Speed Speed 46 1 33 1.39 46 2 29 1.59 0 9 0 9 46
3 25 1.84 9 13 0 13 9 13 46 4 21 2.19 13 17 13 17 13 17 46 5 17
2.71 17 21 17 21 17 21 46 6 15 3.07 21 25 21 25 21 25 46 7 13 3.54
25 25 25 46 8 11 4.18 34 1 33 1.03 34 2 29 1.17 0 9 0 9 34 3 25
1.36 9 13 0 13 9 13 34 4 21 1.62 13 17 13 17 13 17 34 5 17 2 17 21
17 21 17 21 34 6 15 2.27 21 25 21 25 21 25 34 7 13 2.62 25 25 34 8
11 3.09
[0055] With reference to FIG. 5, the controller 58 monitors the
speed of the bicycle (P-1) and continues to operate the
transmission through the range of gear steps corresponding to the
selected gear step range (P-2). When the controller 58 detects that
the speed of the bicycle has rapidly decreased below a threshold
speed (P-3), the controller 58 enters into an elapsed mode. In the
illustrated arrangement of Table 4, the threshold speed Y is the
maximum speed of the speed range for the lowest gear step in the
gear step range (i.e., 9 km/hr). It is anticipated that the
threshold speed Y can be speeds; however, the illustrated
arrangement effectively removes the lowest gear step from the
active gear step range.
[0056] In the elapsed mode, the controller changes the selected
gear steps of the active gear step range to eliminate at least one
of the lower gear steps in the gear step range (P-4). In the
illustrated arrangement, the lowest gear step is eliminated by
changing the speed range of the second to lowest gear step. The
other speed ranges are unaffected. In some arrangements, the lowest
gear step can be eliminated and each of the other speed ranges can
be adjusted to account for the lower end change.
[0057] After adjusting the gear step range, the transmission is
operated within the smaller range of gear steps until the bicycle
speed again exceeds a threshold speed Z (P-5). While not depicted,
operating the transmission in the smaller range of gear steps
includes sensing the bicycle speed and automatically shifting gears
within the smaller range of gear steps. In the illustrated
arrangement, once the speed has exceeded the threshold speed Z, the
controller returns the eliminated gear step or steps to the gear
step range (P-6). In one arrangement, the threshold speeds Y, Z are
the same speed and, in another arrangement, the threshold speeds Y,
Z differ.
[0058] Although the present invention has been described in terms
of a certain embodiment, other embodiments apparent to those of
ordinary skill in the art also are within the scope of this
invention. Thus, various changes and modifications may be made
without departing from the spirit and scope of the invention. For
instance, various components may be repositioned as desired and
certain steps of the control routines can be rearranged and
repositioned. Moreover, not all of the features, aspects and
advantages are necessarily required to practice the present
invention. Accordingly, the scope of the present invention is
intended to be defined only by the claims that follow.
* * * * *