Note: Descriptions are shown in the official language in which they were submitted.
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AUXILIARY POWER UNIT STARTING APPARATUS FOR AN ELECTRIC
BICYCLE
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to an auxiliary power unit starting
apparatus for an electric bicycle, more particularly to a starting apparatus
that
can convert the rider's pedaling force into mechanical displacement at the
time
the rider is pedaling the bicycle, and the mechanical displacement can start
the
auxiliary power unit of the electric bicycle.
Description of the Prior Arts
Electric bicycle is very popular with all age groups due to it is
environment friendly and has the advantage of and easy operation. So far,
there
are various methods and times of starting the auxiliary power unit of an
electric
bicycle.
For example, the electric bicycle in the early days was always provided
at the left handlebar with a switch that is to be controlled by the user,
however,
the operation of it is not easy since the user has to control the switch by
hand.
Therefore, JP Patent Application 20001-055399 discloses a method of detecting
the running resistance and the running speed by using precision-control unit,
and then the running data collected and calculated by the precision-control
unit
is used to control the time of starting the motor. Besides, JP Patent
Applications
2001-301293 and 09-268415 also disclose a method of controlling the time of
starting the motor based on the running data that are measured by
dynamometer, logic circuit and the like electronic element.
Another method is disclosed in JP Patent application 11-290777, in
which, an idler shaft is disposed parallel to and between the crank axle and
the
output axle, and pedaling-force measuring device is mounted on the idler shaft
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for measuring the pedaling force applied to the crank axle, and then the motor
starting time is controlled based on the pedaling force.
As mentioned above, for most of the conventional electric bicycles, their
time of starting the auxiliary power unit is controlled by precision-control
electronic componentor sensor that is used to detect the running resistance or
the pedaling force, and then the time of starting the auxiliary power unit is
controlled based on the running data. However, by using the electronic
precision
electronic elements and complicated measuring instruments, the cost and the
failure rate will be accordingly high. Furthermore, by using electronic
componentto judge the pedaling force of the rider, would probably give rise to
a
false judgment. For example, the riders of all age groups may have different
pedaling force, so if the reference value of the pedaling force is set at a
over
high level, it will be resulted in an uneasy operation, and if the reference
value of
the pedaling force is set at a too low level, it will result in a false
starting time of
starting the motor.
The present invention has arisen to mitigate and/or obviate the afore-
described disadvantages.
SUMMARY OF THE INVENTION
The primary objective of the present invention is to provide an auxiliary
power unit starting apparatus for an electric bicycle, which can convert the
rider's pedaling force into mechanical displacement at the time the bicycle is
being pedaled, and then the mechanical displacement can start the auxiliary
power unit of the electric bicycle. The device of the present invention has
simple
structure and small size, and it can be easily manufactured and assembled.
The present invention will become more obvious from the following
description when taken in connection with the accompanying drawings, which
show, for purpose of illustrations only, the preferred embodiment in
accordance
with the present invention.
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BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is an exploded view of an auxiliary power unit starting apparatus
for an electric bicycle in accordance with the present invention;
Fig. 2 is an amplified view of a driving disc of the present invention;
Fig. 3 is an assembly view of an auxiliary power unit starting apparatus
for an electric bicycle in accordance with the present invention;
Fig. 4 shows an electric bicycle equipped with an auxiliary power unit
starting apparatus in accordance with the present invention;
Fig. 5 is a plan view of the auxiliary power unit starting apparatus for an
electric bicycle in accordance with the present invention;
Fig. 6 is a side view of the auxiliary power unit starting apparatus for an
electric bicycle in accordance with the present invention;
Fig. 7 is an operational plan view of the auxiliary power unit starting
apparatus for an electric bicycle in accordance with the present invention;
Fig. 8 is an operational side view of the auxiliary power unit starting
apparatus for an electric bicycle in accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Figs. 1-6, an auxiliary power unit starting apparatus for an
electric bicycle in accordance with a preferred embodiment of the present
invention is shown and comprises a sprocket 20, a driving disc 30, a plurality
of
positioning springs 40, a crank arm 50, a plurality of triggers 60, a
triggering disc
70 and a switch 80.
The sprocket 20 is rotatably fixed to the frame 10, the peripheral teeth
21 of the sprocket 20 are meshed with a chain 11 that is connected to the
flywheel 12 of the rear wheel, thus forming a bicycle drive train. On the
sprocket
20 are arranged a plurality of openings 22 and a central hole 24, and at a
side of
the sprocket 20 are formed a plurality of projections 23.
The driving disc 30 is rotatably disposed at a side of the sprocket 20 in
such a manner that an axial tube 33 at a side of the driving disc 30 is
engaged in
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the central hole 24 of the sprocket 20, and a C-shaped retainer 34 is used to
stop the disengagement of the driving disc 30. Between the axial tube 33 and
the central hole 24 is arranged a bearing 35. The driving disc 30 is provided
with
a plurality of limiting holes 31 which are to be correspondingly inserted in
the
projections 23 of the sprocket 20, so that the driving disc 30 is allowed to
rotate
relative to the sprocket 20 within the limit of the limiting hole 31. At the
abutting
side of the driving disc 30 abutting the sprocket 20 are arranged a plurality
of
chutes 32 each of which is slanted from a shallow end 321 towards a deep end
322 gradually.
Two ends of the positioning springs 40 are hooked to the driving disc 30
and the sprocket 20, respectively, so as to make the projections 23 abut
against
an end of the limiting holes 31.
The crank arm 50 is fixed to the driving disc 30, and a pedal 13 is
disposed at the end of the crank arm 50.
Each of the triggers 60 includes a thick portion 61 and a thin portion 62,
at a top surface of the thin portion 62 is formed a threaded hole 621. A
return
spring 63 is axially mounted on the thin portion 62, and the thin portion 62
of the
trigger 60 is set in the openings 22 of the sprocket 20, so that the thick
portion
61 of the triggers 60 abut against the deep end 322 of the respective chutes
32.
The triggering disc 70 is disposed at another side of the sprocket 20 in
such a manner that the threaded hole 621on the thin portion 62 of the triggers
60 is fixed to the surface of the triggering disc 70 by means of screws.
The switch 80 is located at the same side of the sprocket 20 as the
triggering disc 70, when it is triggered by the triggering disc 70 at a right
time,
the auxiliary power unit of the electric bicycle will be started.
At the instant that the pedal 13 is being pedaled, the crank arm 50 will
be caused to rotate, so will the driving disc 30 since it is linked to the
crank arm
50. The rotation travel of the driving disc 30 is limited by the limiting
holes 31
and the projections 23 (as shown in Fig. 7), the rotation of the driving disc
30 will
cause a movement of the projection 23 from one end of the limiting hole 31 to
the other, meanwhile, the thick portion 61 of the trigger 60 will move
gradually
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from the deep end 321 of the chute 32 toward the shallow end 321. After the
trigger 60 moves to the shallow end 321, the trigger 60 will be caused to push
the triggering disc 70 outward (as shown in Fig. 8). Thus, the outward
movement
of triggering disc 70 will trigger the switch 80 to start the auxiliary power
unit 14.
It is to be noted that, unlike the conventional method of detecting the
pedaling force of the rider, the device of the present invention is to
transform the
pedaling force into mechanical displacement (the outward movement of the
triggering disc), and then the mechanical displacement can trigger the switch
80
to start the auxiliary power unit without application of any electronic
components.
Furthermore, the device of the present invention has simple structure and
small
size, and it can be easily manufactured and assembled.
On the other hand, the switch 80 is preferably proximity switch.
The device of the present invention can enable the auxiliary power unit
to be started at the time the pedal is being pedaled, while the auxiliary
power
unit will be stopped when user stops pedaling the bicycle. Since the operation
of
the auxiliary power unit is controlled by mechanical displacement, false
triggering will be eliminated.
While we have shown and described various embodiments in
accordance with the present invention, it should be clear to those skilled in
the
art that further embodiments may be made without departing from the scope of
the present invention.
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