Related Applications
[0001] This application is based on and claims priority to Korean Patent Application No.
10-2015-0085831, filed on June 17, 2015, the disclosure of which is incorporated herein in its entirety by reference.
Field of the Invention
[0002] The present invention relates to an ice selector for crushing ice for a refrigerator
and a method of operating the ice selector.
Background of the Invention
[0003] A refrigerator is an apparatus for storing food at a relatively low temperature and
may be configured to store food in a frozen state or a refrigerated state. A decision
to store food in a frozen state or refrigerated state may depend on the kind of food
to be stored.
[0004] The interior of the refrigerator is cooled by supplied cold air, in which the cold
air is typically generated by a temperature exchange action of a refrigerant according
to a cooling cycle including compression, condensation, expansion and evaporation.
The cold air supplied to the inside of the refrigerator can be distributed in the
refrigerator by convection. Thus, items within the refrigerator can be stored at a
desired temperature.
[0005] A refrigerator typically includes a main body having a rectangular parallelepiped
shape with an open front side. A refrigerating compartment (e.g.; refrigerating space,
portion, room, etc.) and a freezing compartment (e.g.: freezing space, portion, room,
etc.) may be provided within the main body. A refrigerating compartment door and a
freezing compartment door for selectively closing and opening the refrigerator compartment
and the freezing compartment may be provided on the front side or surface of the main
body. A plurality of drawers, shelves and container boxes for storing different kinds
of food in a desired state may be provided in the internal storage spaces of the refrigerating
compartment and freezing compartment.
[0006] Conventionally, mainstream refrigerators are top-mount-type refrigerators having
a freezing compartment positioned at an upper side or portion of the refrigerator
and a refrigerating compartment positioned at the lower side or portion of the refrigerator.
There are also commercially available bottom-freeze-type refrigerators. Bottom-freeze-type
refrigerators can enhance user convenience in which a more frequently-used refrigerating
compartment is positioned at an upper portion of the refrigerator and a less frequently
used freezing compartment is positioned at a lower portion of the refrigerator. This
provides an advantage in that a user can conveniently use the refrigerating compartment.
However, the bottom-freeze-type refrigerators (in which the freezing compartment is
positioned at the lower portion or side) can pose an inconvenience when a user does
access the freezing compartment, in that a user typically has to bend at the waist
to open the freezing compartment door (e.g., to take out pieces of ice, food, etc.).
[0007] Traditional attempts at solving the above problem in the bottom freeze type refrigerators
have included an ice dispenser installed in the refrigerating compartment or refrigerating
compartment door in some implementations. In this approach, the refrigerating compartment
door or the inside of the refrigerating compartment may be provided with an ice maker
which generates ice.
[0008] The ice-making device may include an ice-making assembly provided with an ice tray
for producing pieces of ice (e.g., in various shapes including cubes, cylindrical,
semi-spherical, etc.), an ice bucket which stores the pieces of ice, and a feeder
assembly which feeds the pieces of ice stored in the ice bucket to the dispenser.
[0009] The ice which is made in the ice making assembly may fall to the ice bucket positioned
below the ice tray and may accumulate inside the ice bucket. Further, the ice which
is stored in the ice bucket may be transferred to a front discharge port by the transfer
assembly.
[0010] The transfer assembly may be configured to include an auger motor generating a torque
applied to an auger that transfers ice forward, a flange coupled with the auger to
transfer the torque of the auger motor to the auger, an ice crusher rotating together
with the auger to crush ice, and an ice selector for selecting whether or not the
ice is crushed by the ice crusher.
[0011] In this configuration, the ice selector is an apparatus which may be coupled via
a connection member (e.g., link, etc.) to the ice crusher. The ice crusher typically
includes an AC motor supplied with AC power, a moving member connected to the AC motor,
and a lever portion connected to the moving member and the connection member. The
lever portion selectively provides an external force to the connection member depending
on a position of the level portion corresponding to a selection of whether or not
to crush ice.
[0012] However, traditional ice selectors are typically operated at a relatively high voltage
since the AC motor is supplied with the AC power. This can have a very loud operating
sound that causes additional noise while crushing ice. Furthermore, traditional ice
selectors are often supplied with the AC power even in the standby state (e.g., when
it does not crush ice) resulting in increased power consumption. A conventional standby
state can result in heat generation even when not crushing ice. The heat generation
can increase a risk of fire. Even if traditional ice selectors may be operated quickly
(e.g., by directly transmitting power or force from the AC motor to the moving member,
etc.), usually there is still an objectionable operating noise.
Summary of the Invention
[0013] Embodiments include ice selector devices and methods. In one embodiment, an ice selector
operates to crush ice in a refrigerator with relatively low operating noise. The ice
selector is capable of increasing performance while reducing power consumption and
reducing heat output by not applying power in a standby state in which ice is not
crushed.
[0014] In one embodiment, a refrigerator ice selector, comprises: a motor portion configured
to rotate a shaft; a reducer configured to be coupled to the motor portion; a connecting
rod portion coupled to the reducer, the connecting rod configured to perform a linear
reciprocating motion depending on a rotating direction of the shaft; and a lever portion
having one side coupled to the connecting rod portion and the other side coupled to
a connection member of an ice crusher, the lever portion configured to provide an
external force to the connection member depending on a force from the connecting rod
portion. The motor portion can be a DC motor which includes a shaft that can rotate
two different directions.
[0015] In one exemplary implementation, the reducer can include: a worm gear portion formed
on a rotating shaft of the motor portion; a first gear portion coupled to the worm
gear portion, the first gear portion configured to rotate depending on force from
the worm gear portion; a second gear portion coupled to the first gear portion, the
second gear portion configured to move based upon a force from the first gear portion,
second gear portion having a diameter lager than that of the first gear portion; and
a rack gear portion formed at one side of the connecting rod portion, the rack gear
configured to be supplied with a force from the second gear portion and include a
rack gear portion. The first gear portion can include: a first driven gear coupled
to the worm gear portion; and a driving gear coupled to the first driven gear, the
driving gear configured to rotate with the first driven gear. The second gear portion
can include: a second driven gear coupled to the driving gear; and a pinion gear coupled
to the second driven gear and the rack gear portion, the pinion gear configure to
rotate with the second driven gear. The driving gear can have a substantially equal
or smaller diameter size than that of the first driven gear, the second driven gear
has a diameter larger than that of the driving gear, and the pinion gear has a substantially
equal or smaller diameter size than that of the second driven gear. The lever portion
may include a connection groove in which the connection member is fitted.
[0016] In one embodiment, a method of crushing ice includes: selectively operating a motor
causing a shaft to rotate in a first direction or a second direction; introducing
a difference between a first speed and a first torque at which a first gear coupled
to the shaft rotates and a second speed and second torque at which a second gear rotates,
the first gear coupled to the second gear; moving a support member of an ice crusher
in accordance with rotation of the second gear; and crushing ice in accordance with
the selective operation of the motor. The motor can be a DC motor. The method can
further comprise an ice selector process including: receiving a rotational first force
from the shaft; translating the rotational first force to a rotational second force;
and converting the rotational second force into a rotational third force; wherein
the rotational second force is generated at a greater rotational speed and lower torque
than the rotational third force;and transforming the rotational third force into a
linear fourth force. The force from the shaft can be translated into a force of the
first gear. The converting can include converting the second force into the third
force, wherein a first rotation speed and torque associated with the second force
and a second rotation speed and torque associated with the third force are different.
The converting can include creating a difference in a first rotational speed and first
torque associated with the first gear compared to a second rotational speed and second
torque associated with the second gear. The size of the first gear portion can be
different from the size of the second gear portion.
[0017] In one embodiment a reducer can include: a worm gear portion formed on a rotating
shaft of the motor portion; a first gear portion coupled to the worm gear portion,
the first gear portion configured to rotate depending on force from the worm gear
portion; a second gear portion coupled to the first gear portion, the second gear
portion configured to move based upon a force from the first gear portion and the
second gear portion having a diameter lager than that of the first gear portion; and
a rack gear portion formed at one side of the connecting rod portion, the rack gear
configured to be supplied with a force from the second gear portion and include a
rack gear portion. The first gear portion can include: a first driven gear coupled
to the worm gear portion; and a driving gear coupled to the first driven gear, the
driving gear configured to rotate with the first driven gear. The second gear portion
can include: a second driven gear coupled to the driving gear; and a pinion gear coupled
to the second driven gear and the rack gear portion, the pinion gear configured to
rotate with the second driven gear. The driving gear can have a substantially equal
or smaller diameter size than that of the first driven gear, the second driven gear
has a diameter larger than that of the driving gear, and the pinion gear has a substantially
equal or smaller diameter size than that of the second driven gear. The lever portion
can include a connection groove in which the connection member is fitted.
Brief Description of the Drawings
[0018] The objects and features of the present invention will become apparent from the following
description of embodiments given in conjunction with the accompanying drawings, in
which:
FIG. 1 is a perspective view illustrating an ice maker of a refrigerator in which
an ice selector for crushing ice according to an embodiment of the present invention
is installed;
FIG. 2 is a side cross-sectional view of FIG. 1;
FIG. 3 is a diagram illustrating a configuration of the ice selector for crushing
ice according to an embodiment of the present invention; and
FIG. 4 is a diagram viewing FIG. 3 from "A".
FIG. 5 is a flow chart of an exemplary ice crushing method in accordance with one
embodiment.
FIG. 6 is a flow chart of an exemplary ice selector operation method in accordance
with one embodiment. The ice selector method can include a process of reducing the
power or force supplied from a motor portion by a reducer.
Detailed Description of the Embodiments
[0019] Reference will now be made in detail to the preferred embodiments, examples of which
are illustrated in the accompanying drawings. While the invention will be described
in conjunction with the preferred embodiments, it will be understood that they are
not intended to limit the invention to these embodiments. On the contrary, the invention
is intended to cover alternatives, modifications and equivalents, which may be included
within the spirit and scope of the invention as defined by the appended claims. Furthermore,
in the following detailed description of the present invention, numerous specific
details are set forth in order to provide a thorough understanding of the present
invention. However, it will be obvious to one ordinarily skilled in the art that the
present invention may be practiced without these specific details. In other instances,
well known methods, procedures, components, and circuits have not been described in
detail as not to unnecessarily obscure aspects of the current invention.
[0020] Terms including an ordinal number such as 'first', "second', etc., can be used to
describe various components, but the components are not to be construed as being limited
to the terms. The terms are used to distinguish one component from another component.
[0021] It is to be understood that when one element is referred to as being "connected to"
or "coupled to" another element, it may be connected directly to or having another
element intervening inbetween. On the other hand, it is to be understood that when
one element is referred to as being "connected directly to" or "coupled directly to"
another element, it may be connected to or coupled to another element without the
other element intervening inbetween.
[0022] Terms used in the present application are used in order to describe specific embodiments
rather than limiting the present invention. Singular forms are intended to include
plural forms unless the context clearly indicates otherwise. It will be further understood
that the terms "comprises" or "have" used in this application, specify the presence
of stated features, numerals, steps, operations, components, parts, or a combination
thereof, but do not preclude the presence or addition of one or more other features,
numerals, steps, operations, components, parts, or a combination thereof.
[0023] FIG. 1 is a perspective view illustrating an ice maker of a refrigerator in which
an ice selector for crushing ice according to an embodiment of the present invention
is installed and FIG. 2 is a side cross-sectional view of FIG. 1.
[0024] Referring to FIGS. 1 and 2, an ice maker 100 installed in a refrigerator (not shown)
includes an ice making assembly 110. The ice making assembly 110 includes an ice tray
111 configured to generate ice, an ice bucket 120 configured to store the generated
ice, and a transfer assembly 130 configured to transfer the ice stored in the ice
bucket 120 to a dispenser.
[0025] The ice made in the ice making assembly 110 falls into the ice bucket 120 which is
positioned under the ice tray 111 and may be accumulated inside the ice bucket 120.
Further, the ice stored in the ice bucket 120 may be transferred to a front discharge
port 121 by the transfer assembly 130.
[0026] The transfer assembly 130 may be configured to include an auger motor 131 generating
a torque, an auger portion 132 driven by the torque of the auger motor 131 and configured
to transfer ice forward, a flange 133 coupled with the auger portion 132 to transfer
the torque of the auger motor 131 to the auger portion 132, an ice crusher 134 rotating
together with the auger portion 132 and configured to crush ice, and an ice selector
200 operable to select whether or not the ice is crushed by the ice crusher 134.
[0027] In one embodiment, the ice crusher 134 includes a blade 135 rotating together with
the auger portion 132 to crush ice, a support member 136 disposed under the blade
135 to support ice while being crushed by the blade 135, and a connection member 137
coupling the support member 136 and the ice selector 200 to transmit power from the
ice selector 200 to the support member 136.
[0028] When the ice selector 200 is driven up and down, the connection member 137 rotates
and moves to thereby allow the support member 136 to support ice or not to support
ice. Therefore, the ice may be supplied to the dispenser through the discharge port
121 in a crushed or not crushed state.
[0029] An example ice selector 200 for crushing ice according to one embodiment of the present
invention can be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram illustrating
a configuration of the ice selector for crushing ice according to an embodiment and
FIG. 4 is a diagram viewing FIG. 3 from cut away line "A".
[0030] The ice selector 200 may include a motor portion 210, a reducer 220, a connecting
rod portion 230, and a lever portion 240. Referring to FIG. 3, the motor portion 210
is a component which is supplied with power to generate movement. A bi-directional
motor which can rotate in one direction or in an opposite direction (e.g., forward
and reverse, right and left, clockwise and counter-clockwise, etc.) may be used. The
motor portion 210 may be a DC type motor which may be driven by DC power. The motor
portion 210 can rotate in different directions (e.g., forward or reverse) by changing
the polarity of power supplied to the motor portion 210. Changing the direction of
the motor portion can result in ice being crushed or not crushed.
[0031] The reducer 220 is disposed at one side of the motor portion 210. Power for the reducer
220 and the motor portion 210 may come from the same source. The reducer 220 can be
supplied with power from the motor portion 210 and may reduce revolutions per minute
(RPM) of the supplied power and increase the torque. Therefore, the power of the motor
portion 210 may have a reduced RPM while increasing torque by the reducer 220.
[0032] The connecting rod portion 230 may be coupled with the reducer 220 to perform a linear
reciprocating motion depending on the rotational direction of the motor portion 210.
The connecting rod portion 230 may be coupled with the reducer 220 by coupling or
combining gear mechanisms. For example, when the motor portion 210 rotates in one
direction, the connecting rod portion 230 may move in one direction (e.g., rise, forward,
etc.) and when the motor 210 rotates in an opposite direction, the connecting rod
portion 230 may move in another direction (e.g., fall, reverse, etc.).
[0033] In one exemplary implementation, one side of the lever portion 240 is coupled with
the connecting rod portion 230 and thus may integrally move with the connecting rod
portion 230. When the connecting rod portion 230 rises, the lever portion 240 also
rises and when the connecting rod portion 230 falls, the lever portion 240 also falls.
[0034] The other side of the lever portion 240 may be coupled to the connection member 137
to provide an external force to the connection member 137 and which transfers the
force to the ice crusher 134. The ice may be crushed or may not be crushed, depending
on the change in the position of the lever portion 240 and the connecting rod portion
230 which transfers the external force to the connection member 137. The lever portion
240 may be provided with a connection groove 241 in which the connection portion 137
is fitted.
[0035] In one embodiment, the reducer 220 may be configured to include a worm gear portion
221, a first gear portion 222, a second gear portion 223, and a rack gear portion
224. The first gear portion 222, the worm gear portion 221, second gear portion 223,
and rack gear portion 224 are coupled by coupling or combining gear mechanisms. The
worm gear portion 221 is formed on a rotating shaft 211 of the motor portion 210 and
transfers power or force from the motor portion 210 while rotating together with the
rotating shaft 211. The first gear portion 222 may rotate by being supplied with power
or force from the worm gear portion 221. The second gear portion 223 rotates by being
supplied with power or force from the first gear portion 222. The second gear portion
223 has a diameter larger than that of the first gear portion 222 and thereby reduces
revolutions per minute (RPM) of second gear portion 223 compared to first gear portion
222. The rack gear portion 224 can be supplied with power or force from the second
gear portion 223. The rack gear portion 224 may be formed at one side of the connecting
rod portion 230.
[0036] The first gear portion 222 is configured to include a first driven gear 222a and
a driving gear 222b as illustrated in FIG. 4 in accordance with one embodiment. The
first driven gear 222a is coupled with the worm gear portion 221 and thus may rotate
by being supplied with power or force from the worm gear portion 221. The driving
gear 222b is coupled with the first driven gear 222a via shaft 222c and thus may rotate
at the same RPM and torque as the first driven gear 222a. In one exemplary implementation,
the second gear portion 223 is configured to include a second driven gear 223a and
a pinion gear 223b. The second driven gear 223a is coupled with the driving gear 222b
and thus rotates by being supplied with power or force from the driving gear 222b.
[0037] In one embodiment, the second driven gear 223a has a diameter larger than that of
the driving gear 222b and thus has a gear ratio larger than 1:1, and as a result may
obtain the effect of reducing the RPM in the second driven gear 223a compared to the
driving gear 222b and increasing the torque. The driving gear 222b may have the same
diameter as the first driven gear 222a or a diameter smaller than that of the first
driven gear 222a.
[0038] The pinion gear 223b may be coupled with the second driven gear 223a via shaft 223c
to rotate at the same RPM and torque as the second driven gear 223a and may be coupled
with the rack gear portion 224 to transfer power to the connecting rod portion 230.
The pinion gear 223b may be formed at the same diameter as the second driven gear
223a or a diameter smaller than that of the second driven gear 223a.
[0039] The power or force from the motor portion 210 can be transferred to the connecting
rod portion 230 and the lever portion 240. The operating speed of the lever portion
240 may be slow and the force applied by lever portion 240 may be changed significantly.
Therefore, the noise may be also reduced while the lever portion 240 is being operated
to apply force to the connection member 137.
[0040] FIG. 5 is a flow chart of an exemplary ice crushing method in accordance with one
embodiment. A motor is selectively operated causing a shaft to rotate in a first direction
or a second direction (e.g., S510). A difference is introduced between a first speed
and a first torque at which a first gear coupled to the shaft rotates and a second
speed and second torque at which a second gear rotates (e.g., S520). In one embodiment,
the difference is introduce by an ice selector operation. The first gear is coupled
to the second gear. A support member of an ice crusher is moved in accordance with
rotation of the second gear (e.g., S530). Ice is crushed in accordance with the selective
operation of the motor (e.g., S540).
[0041] FIG. 6 is a flow chart of an exemplary ice selector operation method in accordance
with one embodiment. The ice selector method can include a process of reducing the
power or force supplied from a motor portion by a reducer.
[0042] A first power or force from a motor portion is received (e.g., S610). In one exemplary
implementation, the motor portion includes a DC motor.
[0043] The first power or force is translated to a second power or force (e.g., S620). A
first power or force from a motor portion can be translated into a second power or
force. In one embodiment, a power or force from a motor portion is translated into
a power or force of a first gear portion.
[0044] A second power or force is converted into a third power or force (e.g.,S630). In
one exemplary implementation, one rotational power or force is converted into another
rotational power or force. The conversion can include creating a difference in the
rotational speed (e.g., RPM, etc.) and torque of the second power or force compared
to the third power or force. The difference can include the rotational speed of the
third power or force is slower than the rotational speed of the second power or force
while the torque of the third power or force is greater than the torque of the second
power or force. In one embodiment, a power or force from a first gear portion is converted
into a power or force of a second gear portion. The size of the first gear portion
can different from the size of the second gear portion.
[0045] The third power or force is transformed into a fourth power or force (e.g., S640).
In one embodiment, a power or force from a second gear portion is transformed into
the power or force of a connecting rod member. A rotational power or force of the
second gear portion can be transformed into a linear reciprocating power or force
of connecting rod member.
[0046] In one embodiment, a process of transferring the power supplied from the reducer
220 to the connecting rod portion 230 may be performed. The rack gear portion 224
may be formed on one side of the connecting rod portion 230 so that the connecting
rod portion 230 may be supplied with the power supplied from the reducer 220. Further,
a process of transferring the power supplied from the connecting rod portion 230 to
the lever portion 240 may be performed. When the power is transferred to the lever
portion 240, the lever portion 240 together with the connecting rod portion 230 performs
a linear reciprocating motion. The connection member 137 of the ice crusher 134 may
be operated depending on the change in the position of the lever portion 240.
[0047] In one embodiment, it is possible for the motor portion and ice selector for crushing
ice to reduce operating noise compared to traditional approaches. The motor portion
may include a DC motor supplied with the DC power. The voltage may be selectively
applied at the time of the operation so as not to apply power in the standby state
in which ice is not crushed, thereby reducing the power consumption of the product
and reducing the heating value compared to traditional approaches. The operating power
can also be by reduced using the reducer. The RPM of the power or force supplied from
the motor portion may be reduced and the torque may be increased by the reducer, thereby
reducing power consumption.
[0048] While the present invention has been described with respect to the preferred embodiments,
the scope of the present invention is not limited to the specific embodiments. It
will be understood that a person having ordinary skill in the art to which the present
invention pertains may substitute and change components without any limitation and
these substitutions and changes also belong to the scope of the present invention.
[0049] The foregoing descriptions of specific embodiments of the present invention have
been presented for purposes of illustration and description. They are not intended
to be exhaustive or to limit the invention to the precise forms disclosed, and obviously
many modifications and variations are possible in light of the above teaching. The
embodiments were chosen and described in order to best explain the principles of the
invention and its practical application, to thereby enable others skilled in the art
to best utilize the invention and various embodiments with various modifications as
are suited to the particular use contemplated. It is intended that the scope of the
invention be defined by the Claims appended hereto and their equivalents. The listing
of steps within method claims do not imply any particular order to performing the
steps, unless explicitly stated in the claims.
1. A refrigerator ice selector, comprising:
a motor portion configured to rotate a shaft;
a reducer configured to be coupled to the motor portion;
a connecting rod portion coupled to the reducer, the connecting rod configured to
perform a linear reciprocating motion depending on a rotating direction of the shaft;
and
a lever portion having one side coupled to the connecting rod portion and the other
side coupled to a connection member of an ice crusher, the lever portion configured
to provide an external force to the connection member depending on a force from the
connecting rod portion.
2. The ice selector of claim 1, wherein the motor portion is a DC motor which includes
a shaft that can rotate two different directions.
3. The ice selector of claim 1, wherein the reducer includes:
a worm gear portion formed on a rotating shaft of the motor portion;
a first gear portion coupled to the worm gear portion, the first gear portion configured
to rotate depending on force from the worm gear portion;
a second gear portion coupled to the first gear portion, the second gear portion configured
to move based upon a force from the first gear portion, second gear portion having
a diameter lager than that of the first gear portion; and
a rack gear portion formed at one side of the connecting rod portion, the rack gear
configured to be supplied with a force from the second gear portion and include a
rack gear portion.
4. The ice selector of claim 3, wherein the first gear portion includes:
a first driven gear coupled to the worm gear portion; and
a driving gear coupled to the first driven gear, the driving gear configured to rotate
with the first driven gear.
5. The ice selector of claim 4, wherein the second gear portion includes:
a second driven gear coupled to the driving gear; and
a pinion gear coupled to the second driven gear and the rack gear portion, the pinion
gear configure to rotate with the second driven gear.
6. The ice selector of claim 5, wherein the driving gear has a substantially equal or
smaller diameter size than that of the first driven gear, the second driven gear has
a diameter larger than that of the driving gear, and the pinion gear has a substantially
equal or smaller diameter size than that of the second driven gear.
7. The ice selector of claim 1, wherein the lever portion includes a connection groove
in which the connection member is fitted.
8. A method of crushing ice comprising:
selectively operating a motor causing a shaft to rotate in a first direction or a
second direction;
introducing a difference between a first speed and a first torque at which a first
gear coupled to the shaft rotates and a second speed and second torque at which a
second gear rotates, the first gear coupled to the second gear,
moving a support member of an ice crusher in accordance with rotation of the second
gear; and
crushing ice in accordance with the selective operation of the motor.
9. The method of claim 8 wherein the motor is a DC motor.
10. The method of claim 8 further comprising an ice selector process including:
receiving a rotational first force from the shaft;
translating the rotational first force to a rotational second force; and
converting the rotational second force into a rotational third force; wherein the
rotational second force is generated at a greater rotational speed and lower torque
than the rotational third force; and
transforming the rotational third force into a linear fourth force.
11. The method of claim 8 wherein force from the shaft is translated into a force of the
first gear.
12. The method of claim 8 wherein the converting include converting the second force into
the third force, wherein a first rotation speed and torque associated with the second
force and a second rotation speed and torque associated with the third force are different.
13. The method of claim 8 Wherein the converting include creating a difference in a first
rotational speed and first torque associated with the first gear compared to a second
rotational speed and second torque associated with the second gear.
14. The method of claim 8 wherein the size of the first gear portion can different from
the size of the second gear portion.