U.S. patent application number 11/078382 was filed with the patent office on 2006-09-14 for battery powered motor system for low power application.
This patent application is currently assigned to Mosway Semiconductor Limited. Invention is credited to Ming Ki Au, Ferenc Fekete, Kenny Chi Ken Lee, Man Keung Mak, Chi Keung Tang, Celement Chiu Sing Tse.
Application Number | 20060205320 11/078382 |
Document ID | / |
Family ID | 36971647 |
Filed Date | 2006-09-14 |
United States Patent
Application |
20060205320 |
Kind Code |
A1 |
Fekete; Ferenc ; et
al. |
September 14, 2006 |
Battery powered motor system for low power application
Abstract
An article of motion such as a toy has moving parts that are
motivated slowly and with low torque by an electronic timepiece
movement.
Inventors: |
Fekete; Ferenc; (Lamma
Island, HK) ; Au; Ming Ki; (North Point, HK) ;
Tse; Celement Chiu Sing; (Kennedy Town, HK) ; Lee;
Kenny Chi Ken; (Tai Po, HK) ; Tang; Chi Keung;
(Tai Po, HK) ; Mak; Man Keung; (Pokfulam,
HK) |
Correspondence
Address: |
LEYDIG VOIT & MAYER, LTD
700 THIRTEENTH ST. NW
SUITE 300
WASHINGTON
DC
20005-3960
US
|
Assignee: |
Mosway Semiconductor
Limited
Central
HK
|
Family ID: |
36971647 |
Appl. No.: |
11/078382 |
Filed: |
March 14, 2005 |
Current U.S.
Class: |
446/484 |
Current CPC
Class: |
G09F 19/02 20130101 |
Class at
Publication: |
446/484 |
International
Class: |
A63H 29/22 20060101
A63H029/22 |
Claims
1. An article of motion comprising moving parts and an electronic
timepiece movement, the parts being driven to move slowly and with
low torque by the electronic timepiece movement.
2. The article of motion as claimed in claim 1, wherein the
timepiece movement includes a two-phase stepping motor.
3. The article of motion as claimed in claim 1, being a doll or
figurine, wherein the parts are body parts of the doll or
figurine.
4. The article of motion as claimed in claim 1, being a toy
vehicle, wherein the parts are wheels of the vehicle.
5. The article of motion as claimed in claim 1, being a Ferris
wheel driven to rotate slowly about an axis by the electronic
timepiece movement.
6. The article of motion as claimed claim 1, being a figurine
mounted to rotate upon a base within which the electronic timepiece
is located.
Description
[0001] The present invention relates to toys, playthings or premium
products such as electronic desktop decorations that produce a
relatively slow and low-torque movement.
BACKGROUND OF THE INVENTION
[0002] There are classes of product in which a slow motion is
desired, for example to mimic life-like movements (the limb
articulation or gestures of a doll, the opening and closing of
eyelids, or human facial expressions). There exist numerous prior
inventions that meet the challenge with heavily geared-down DC
motors, complicated mechanical contraptions, electromagnets, air
bags or combinations thereof, to produce such movements.
[0003] DC motors are widely employed in the toy industry to induce
toy motions, as in battery operated toy cars or animated figures.
While producing high rotational speed and high torque, DC motors
suffer from high current drain, especially when obstructed or
stalled. For example, U.S. Pat. No. 4,695,016 to S. Worack (1987)
described a system that used a DC motor and gear train and complex
mechanical structures to produce a relatively slow throw action
implementing a model train rail switch. The motor disclosed in the
above US patent had to be specially designed for low stall current,
to minimise battery drain when the throw-switch action was
obstructed, as can be expected in model train applications.
[0004] U.S. Pat. No. 6,719,605 to Ichikawa (2004) discloses an
electromagnet to generate a swinging motion on a swinging member,
which is converted into wheel rotation through a ratchet mechanism.
While avoiding the drawbacks of a DC motor based solution, this
electro-magnet based solution was mechanically complicated.
[0005] U.S. Pat. No. 5,462,473 to K. Sheller (1995) discloses a
leaky air bag that is built into collapsible stuffed toys (FIG. 2)
such that when first compressed or folded, the stuffed toy will
return to its relaxed posture slowly, mimicking life-like
motions.
[0006] The above solutions suffer from one shortcoming or
another--complex mechanisms, heavy current drain (especially when
obstructed), or one-shot action that needs re-energizing (leaky
air-bag).
OBJECT OF THE INVENTION
[0007] It is the object of the present invention to overcome or
substantially ameliorated at least one of the above disadvantages
and/or more generally to provide an improved low power article of
motion. It is a further object of the present invention to provide
low cost driving devices suitable for small toys that might be
powered by miniature batteries and without resorting to complicated
mechanisms.
SUMMARY OF THE INVENTION
[0008] According to the invention, there is provided an article of
motion, comprising moving parts and an electronic timepiece
movement, said parts being driven to move slowly and with low
torque by the electronic timepiece movement.
[0009] Preferably, the timepiece movement would typically include a
two-phase step motor.
[0010] In one embodiment, the article of motion is a toy vehicle,
and said parts are wheels of the vehicle.
[0011] In another embodiment, the article of motion is a Ferris
wheel driven to rotate slowly about an axis by the electronic
timepiece movement.
[0012] In yet another embodiment, the article of motion is a
figurine mounted to rotate upon a base within which the electronic
timepiece is located.
[0013] The present invention typically employs a two-phase step
motor, specifically the miniaturised genre as widely applied in
timepieces (FIG. 1), to produce low-speed, low-torque motions
suitable for use in classes of toys that need to move or articulate
slowly.
[0014] The step motor axle rotates a fixed angle characteristic of
its design when appropriate electrical stimulus is applied, and
stay put indefinitely when no stimulus is received. The speed of a
step motor depends solely on the external stimulus, thus
simplifying the gear train needed when high-speed DC motor is used
for low speed application.
[0015] The two-phase step motor typically directly drives the wheel
of a toy car, or the limb or body part of a toy figurine, or the
actuator in a model train railway is scenario. The amount of travel
and the speed of execution are largely dependent on electronic
stimulus applied. Where higher torque is needed, simple gear train
can be installed between the step motor and the load.
[0016] Avoidance of high-ratio gear train lowers system energy loss
during gear transmission, resulting in torque/battery-life
combination optimally suited for slow-moving toys powered by small
battery.
[0017] Two-phase step motors used in the timepiece industry output
low-torque by nature. While a hindrance to other toy applications
with heavier loads, the low torque adds to the safety of the toy,
especially for infant or pre-school toys wherein the infant or
young child is expected to obstruct the toy movements. Upon
intervention the step motor will yield and stop its advance, while
a DC motor would fight and try to continue its rotation, running
down a battery quickly.
BRIEF DESCRIPTION OF DRAWINGS
[0018] The invention will now be more particularly described, by
way of example only, with reference to the accompanying drawings,
in which:
[0019] FIG. 1 is a parts-exploded perspective view of a prior art
timepiece movement of a type including a two-phase step motor which
might be adopted in the present invention;
[0020] FIG. 2 is a schematic perspective view of a first embodiment
of an article of motion in accordance with the invention,
comprising a rotating ballerina figure, a two-phase step motor,
control circuitry and a drive transmission extending from the step
motor to the ballerina figure;
[0021] FIG. 3 is a schematic top plan view of a second embodiment
of an article of motion in accordance with the invention, taking
the form of a toy motor car; and
[0022] FIG. 4 is a schematic side view of a third embodiment of an
article of motion in accordance with the invention, which is a toy
Ferris wheel.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0023] Referring initially to FIG. 2 of the drawings, there is
shown a first article of motion embodying the invention in the form
of a dancing ballerina for decoration, which comprises a ballerina
FIG. 21 driven by a two-phase step motor 29 to turn on a base 39
resembling a stage. The step motor 29 has its output shaft 38
connected to an input gear 26 of an intermediate gear train 20. The
output gear 27 of the gear train 20 has a shaft 22 onto which the
ballerina FIG. 21 is mounted.
[0024] A child trying to stop a ballerina figure driven by a
geared-down DC motor might suffer injury because of the heavy
torque present, or the toy figure might be broken.
[0025] In a step motor based solution, the torque is much lower and
neither the child nor the toy figure will be hurt in the event of
jamming.
[0026] The step motor 29 receives control signals from circuitry 30
powered by battery or batteries 31. The gear train 20, the step
motor 29, the circuitry 30 and the battery 31 are housed in the
base 39 to prevent the child from making contact or tempering with
these parts.
[0027] A variation on this theme is a dance figure that moves in
varied tempo, including periods of suspended animation, thus better
mimicking a real-life dance movement. Such variations can be
conveniently implemented through delivering pre-programmed stimulus
patterns to the step motor 29. This would otherwise require
complicated mechanical mechanisms in a DC motor based solution.
[0028] Referring to FIG. 3, there is shown a second article of
motion embodying the invention in the form of a toy car 10 for a
child to play with. The step motor based toy car 10 will move
slowly, but will provide a much longer play time than a DC motor
based solution, assuming the same battery. Mounted on a chassis 11,
a battery 12 powers the drive electronics circuit board 13 that
delivers appropriate stimulus to step motor 14 that drives the rear
wheel 15 directly or via a low-ratio gear box. When obstructed a DC
motor toy car would draw a stall current typically larger than the
normal operating current, and therefore run down the battery 12
quickly, or even burn out the motor winding. A step motor based toy
car 10 will not draw excessive current when stalled.
[0029] Referring to FIG. 4, there is shown a third article of
motion employing the invention in the form of a toy Ferris wheel 8
for decoration. An electronic driving circuit 16 provides
electronic stimulus to a two-phase step motor 17 which drives the
axis of the Ferris wheel 8 directly. It is conceivable that a child
playing with such a toy might want to stop the Ferris wheel 8
abruptly to load or unload small toy FIG. 18 to or from the
gondolas 19. The low torque of a step motor 17 will not counteract
such an intervention especially if some suitable escapement
mechanism is added between the step motor axis and the Ferris wheel
8 itself. Similarly constructed carousels and merry-go-rounds are
easily conceived.
[0030] A model railway will also benefit from the present
invention. Track-switches, signal lamps, locomotive and rolling
stock can all be driven by the present invention without concern
for obstruction-induced problems. A child can interrupt a
locomotive safely, load a favourite figure before putting the
locomotive back to the track, adding to playing enjoyment.
[0031] Advantages of the present invention include intrinsic low
speed--diminished or remove requirement for gears, low torque--safe
for infants and young children, intervention/obstruction-safe
operation, no stall current upon obstruction, variable speed,
including complete standstill--behaviour determined by external
drive stimulus, low system cost, uses low cost step motor derived
from proven timepiece technology.
[0032] Those skilled in the art will appreciate that the foregoing
is presented by way of illustration only, and not as a limitation.
Changes and modifications may be applied without deviating from the
scope of the invention.
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