U.S. patent application number 10/878868 was filed with the patent office on 2005-12-29 for baby bouncer actuator and related systems.
Invention is credited to Cheung, Kwok Yau William, Wong, Sui-Kay.
Application Number | 20050283908 10/878868 |
Document ID | / |
Family ID | 43742352 |
Filed Date | 2005-12-29 |
United States Patent
Application |
20050283908 |
Kind Code |
A1 |
Wong, Sui-Kay ; et
al. |
December 29, 2005 |
Baby bouncer actuator and related systems
Abstract
The invention provides a novel microprocessor-controlled
actuator which bounces a baby bouncer system at soothing
frequencies that are optimized for the weight of a baby supported
in the baby bouncer system bed. The invention also provides a novel
baby bouncer system which includes the novel
microprocessor-controlled actuator. In one embodiment, the
microprocessor based control system which controls the bouncing
motion of the actuator also emits soothing sounds.
Inventors: |
Wong, Sui-Kay; (North Point,
HK) ; Cheung, Kwok Yau William; (Tai Po N.T.,
HK) |
Correspondence
Address: |
Kevin J. McGough
714 Colorado Avenue
Bridgeport
CT
06605
US
|
Family ID: |
43742352 |
Appl. No.: |
10/878868 |
Filed: |
June 28, 2004 |
Current U.S.
Class: |
5/109 ;
5/105 |
Current CPC
Class: |
A47D 9/02 20130101; A47D
13/107 20130101 |
Class at
Publication: |
005/109 ;
005/105 |
International
Class: |
A47D 009/02 |
Claims
1. An actuator comprising: (a) a housing adapted to engage a baby
bouncer system for transmission of bouncing forces; (b) a motion
sensor which can generate signals corresponding to baby bouncer
system bouncing force and which is enclosed within and supported by
the housing; (c) a microprocessor based control system which can
detect and store the motion sensor signals and which is enclosed
within and supported by the housing; (d) a DC electric motor which
(i) is connectable to a power source, (ii) is in electrical
communication with the microprocessor based control system, (iii)
during operation receives a supply voltage at a level which is
regulated by the microprocessor based control system, and (iv) is
enclosed within and supported by the housing; (e) a speed reduction
mechanism which comprises an axial shaft connected for rotation to
and driven by the DC electric motor and which is enclosed within
and supported by the housing; (f) a rotatable eccentric weight
which is mounted coaxially on the speed reduction mechanism axial
shaft for rotational and pendulum-like motion and which is enclosed
within and supported by the housing; wherein the microprocessor
based control system is calibrated to maintain the DC electric
motor supply voltage level at a value which is optimized to
maintain baby bouncer system bouncing at soothing frequencies.
2. An actuator of claim 1, wherein the speed reduction ratio of the
speed reduction mechanism is set such that the rotational speed of
the actuator's eccentric weight is from about 50 to about 100 times
per minute at a microprocessor-controlled DC motor supply voltage
range of about 40% to about 90% of the maximum DC motor supply
voltage, and the soothing frequency is the baby bouncer system
resonant frequency when supporting a baby.
3. An actuator of claim 1, wherein the microprocessor based control
system is calibrated and regulates DC electric motor voltage supply
by a method comprising: (a) retrieving a value corresponding to the
maximum DC electric motor supply voltage level (Vmax) and setting
DC electric motor supply voltage level Vn initially at Vmax; (b)
selecting an actuator operation time interval t; (c) operating the
actuator for time interval t at Vn and detecting and recording
motion sensor signal values Fn during time interval t; (d)
retrieving a value corresponding to the minimum DC electric motor
supply voltage level (Vmin), detecting Vn, and, if Vn does not
equal Vmin within an acceptable tolerance, adjusting Vn by
subtracting voltage increment v; (e) repeating steps (c) and (d)
until Vn equals Vmin within an acceptable tolerance; (f) comparing
Fn values recorded at each Vn and determining the maximum Fn value
(Fmax) and the Vn corresponding to Fmax (V of Fmax); and (g)
setting DC electric motor voltage supply at V of F max.
4. An actuator of claim 1, wherein the microprocessor based control
system is calibrated and regulates DC electric motor voltage supply
by a method comprising: (a) retrieving a value corresponding to the
maximum DC electric motor supply voltage level (Vmin) and setting
DC electric motor supply voltage level Vn initially at Vmin; (b)
selecting an actuator operation time interval t; (c) operating the
actuator for time interval t at Vn and detecting and recording
motion sensor signal values Fn during time interval t; (d)
retrieving a value corresponding to the maximum DC electric motor
supply voltage level (Vmax), detecting Vn, and, if Vn does not
equal Vmax within an acceptable tolerance, adjusting Vn by adding
voltage increment v; (e) repeating steps (c) and (d) until Vn
equals Vmax within an acceptable tolerance; (f) comparing Fn values
recorded at each Vn and determining the maximum Fn value (Fmax) and
the Vn corresponding to Fmax (V of Fmax); and (g) setting DC
electric motor voltage supply at V of F max.
5. An actuator of claim 3, wherein Vmax is about 90% of the maximum
power supply voltage and Vmin is about 40% of the maximum power
supply voltage.
6. An actuator of claim 4, wherein Vmax is about 90% of the maximum
power supply voltage and Vmin is about 40% of the maximum power
supply voltage.
7. An actuator of claim 3, wherein v is ranges from about 0.1 volts
to about 0.5 volts.
8. An actuator of claim 4, wherein v is ranges from about 0.1 volts
to about 0.5 volts.
9. An actuator of claim 3, wherein the maximum power supply voltage
ranges from about 4.5 volts to about 9 volts.
10. An actuator of claim 4, wherein the maximum power supply
voltage ranges from about 4.5 volts to about 9 volts.
11. An actuator of claim 3, wherein t ranges from about 5 seconds
to about 30 seconds.
12. An actuator of claim 4, wherein t ranges from about 5 seconds
to about 30 seconds.
13. An actuator of claim 1, wherein during operation the actuator
bounces the baby bouncer system at a frequency of around 60 to
around 100 times per minute.
14. An actuator of claim 3, wherein during operation the actuator
bounces the baby bouncer system at a frequency of around 60 to
around 100 times per minute.
15. An actuator of claim 4, wherein during operation the actuator
bounces the baby bouncer system at a frequency of around 60 to
around 100 times per minute.
16. An actuator of claim 3, wherein during operation the actuator
bounces the baby bouncer system at the system resonant
frequency.
17. An actuator of claim 4, wherein during operation the actuator
bounces the baby bouncer system at the system resonant
frequency.
18. An actuator of claim 1, wherein the eccentric weight rotates
from about 50 to about 100 times per minute at DC electric motor
supply voltage levels of about 40% to about 90% of the maximum DC
electric motor supply voltage.
19. An actuator of claim 1, wherein the microprocessor based
control system is programmed to broadcast soothing sounds.
20. An actuator of claim 1, wherein the microprocessor based
control system is programmed to broadcast a prerecorded
message.
21. An actuator of claim 1, wherein the actuator further comprises
a battery pack which powers the DC electric motor.
22. An actuator of claim 1, wherein the voltage-regulated DC
electric motor is powered by electrical connection to an electrical
wall outlet.
23. An actuator of claim 1, wherein the voltage-regulated DC
electric motor is powered by electrical connection to a remote
battery pack or generator.
24. An actuator of claim 1, wherein the DC electric motor voltage
supply is regulated by either a pulse-width modulator (PWM) or
linear voltage regulator under the control of the microprocessor
based control system.
25. An actuator of claim 1, wherein the actuator comprises two
rotatable eccentric weights which: (a) are mounted on the speed
reduction mechanism coaxially with the speed reduction mechanism
shaft for rotational, pendulum-like motion, and (b) are enclosed
within and supported by the housing.
26. An actuator of claim 1, wherein: (a) the actuator is comprised
of two eccentric weights which each weigh about 25 grams to about
500 grams; and (b) the eccentric weights each have an eccentricity
radius which ranges from about 10 millimeters to about 100
millimeters when the speed-reducing mechanism shaft rotates at a
speed of from about 25 to about 150 revolutions per minute.
27. An actuator of claim 1, wherein the maximum voltage supplied to
the DC electric motor ranges from about 3 volts to about 30
volts.
28. An actuator of claim 1, wherein the DC electric motor engages
and rotates the axial shaft of speed-reducing mechanism through a
mechanical linkage.
29. An actuator of claim 12, wherein the mechanical linkage is a
belt pulley system, a gear train, a clutch system, or frictional
wheels.
30. (canceled)
31. (canceled)
32. (canceled)
33. (canceled)
Description
FIELD OF THE INVENTION
[0001] The invention provides a novel microprocessor-controlled
actuator which bounces a baby bouncer system at soothing
frequencies that are optimized for the weight of a baby supported
in the baby bouncer system bed. The invention also provides a novel
baby bouncer system which includes the novel
microprocessor-controlled actuator.
[0002] In one embodiment, the microprocessor based control system
which controls the bouncing motion of the actuator also emits
soothing sounds.
BACKGROUND OF THE INVENTION
[0003] A baby bouncer system comprises a cradle-like seat that
supports and rocks a baby in a seated or prone position and a
resilient metal frame that includes a base adaptable for support by
a relatively uniform surface and an angled segment which extends
upwardly to support the seat. The angled segment may be bent
downwardly toward the base portion of the frame to provide a gentle
rocking movement. The general configuration and design of baby
bouncer frames and seats are well known. See, e.g., U.S. Pat. Nos.
6.594,840 and 5,269,591.
[0004] Bouncer support frames are spring resilient systems. Thus,
the frame will bounce effectively and naturally if subjected to a
bouncing rhythm which approximates the baby bouncer's natural
frequency. The natural bouncing frequency of a baby bouncer varies
depending on the weight of the baby supported in the bouncer seat.
(The average weight of a baby varies from around six to around
twenty-four pounds).
[0005] The most effective rhythm to soothe a baby is believed to be
a rhythm close to the human heart beat rate (a rhythm the baby
becomes accustomed to in the womb). Consequently, a baby bouncer
would preferably bounce at a frequency of from about 70 to about
100 times per minute. Ideally, a properly designed spring-resilient
bouncer support frame system would bounce at a natural frequency
from 60 to 100 times per minute (approximately 1 Hz to about 1.7
Hz) for baby weight ranges of from about 6 to about 24 pounds.
[0006] U.S. Pat. No. 6,629,727 ('727 Patent) discloses an infant
carrier having a bouncer mode of operation in which the bouncer
mechanism establishes harmonic vibration. The carrier of the '727
Patent vibrates at a high frequency and the bouncer mechanism
generates a low-level force.
[0007] Currently available fixed speed actuators (e.g., motorized
swing actuators) have not been employed effectively with baby
bouncers to either affect a natural bouncing motion or achieve
optimum bouncer frequencies.
[0008] Therefore, the need exists for baby bouncers and related
actuators that automatically support and bounce a baby at an
optimum soothing frequency. Such a bouncer would ideally require
minimal manual intervention to ensure continuous and soothing
bouncing and would have the ability to automatically search and set
the actuator's speed to match the naturally bouncing frequency
within a range of 60 to 100 times per minute to resemble a natural,
gentle harmonic bouncing motion.
SUMMARY OF THE INVENTION
[0009] The invention provides a novel microprocessor-controlled
actuator which bounces a baby bouncer system at soothing
frequencies that are optimized for the weight of a baby supported
in the baby bouncer system bed. The invention also provides a novel
baby bouncer system which includes the novel
microprocessor-controlled actuator.
[0010] A microprocessor-controlled actuator of the invention
comprises: (a) a housing adapted to engage and bounce a baby
bouncer system; (b) a motion sensor which can generate signals
corresponding to baby bouncer system forces and which is enclosed
within and supported by the housing; (c) a microprocessor based
control system which can detect and store the motion sensor signals
and which is enclosed within and supported by the housing; (d) a DC
electric motor which (i) is connectable to a power source, (ii) is
in electrical communication with the microprocessor based control
system, (iii) during operation receives a supply voltage at a level
which is regulated by the microprocessor based control system, and
(iv) is enclosed within and supported by the housing; (e) a speed
reduction mechanism which comprises an axial shaft connected for
rotation to and driven by the DC electric motor and which is
enclosed within and supported by the housing; (f) a rotatable
eccentric weight which is mounted coaxially on the speed reduction
mechanism axial shaft for rotational motion to generate centrifugal
force and which is enclosed within and supported by the housing;
wherein the microprocessor based control system is calibrated to
maintain the DC electric motor supply voltage level at a value
which is optimized to maintain baby bouncer system bouncing at a
soothing frequency, e.g., about 1 to 2 Hz.
[0011] The speed reduction ratio of the speed reduction mechanism
is preferably set such that the rotational speed of the actuator's
eccentric weight is from about 50 to about 100 times per minute at
a microprocessor-controlled DC electric motor supply voltage range
of about 40% to about 90% of the maximum motor supply voltage.
[0012] When DC power is supplied to the DC electric motor, the
motor engages the rotating speed reduction mechanism and rotates
the speed reduction axial shaft, causing the eccentric weight to
move in a rotational manner to generate the centrifugal force which
causes the actuator to bounce the baby bouncer system.
[0013] In accordance with the laws of physics, if the actuator
speed approximates or matches the natural bouncing frequency of the
baby bouncer system supporting a baby, the bouncer system will
bounce effectively at the baby bouncer system's natural frequency
(resonance). If the actuator speed does not match the natural
bouncing frequency, irrespective of whether it is faster or slower
than such frequency, the baby bouncer system supporting a baby will
not resonate and will either exhibit a low frequency, intermittent
bouncing motion or no bouncing motion at all.
[0014] As described in detail hereinafter, the microprocessor based
control system is calibrated by a method comprising: (1)
identifying and storing motion sensor signal frequency values (Fn)
over a range of DC electric motor voltage supply levels (Vn); (2)
comparing stored Fn values and identifying the maximum motion
sensor signal frequency value (Fmax) and the DC electric motor
voltage supply level at Fmax (V of Fmax); storing V of Fmax.
[0015] A baby bouncer system of the invention comprises: (a) a
resilient support frame adapted for positioning on a relatively
level surface; (b) a cradle-like bed attached to and supported by
the frame in an elevated position suitable for stable support of a
baby; and (c) a microprocessor-controlled actuator of the
invention, wherein the actuator housing can be mounted for
transmission of bouncing forces on the resilient support frame.
[0016] In one embodiment, the microprocessor based control system
which controls the actuator also contains a voice and
melody-recording and playback microprocessor which generate signals
translatable to soothing sounds which, through a transducer or
other appropriate device, are emitted synchronously with baby
bouncer system bouncing.
[0017] These and other features of the invention are described in
detail in the following detailed description.
BRIEF DESCRIPTION OF THE FIGURES
[0018] FIG. 1 illustrates a side-view of one embodiment of a baby
bouncer system of the instant invention.
[0019] FIG. 2 illustrates a cross-sectional view of one embodiment
of an actuator of the instant invention.
[0020] FIG. 3 illustrates a flow chart used to program a
microprocessor based control system used to control an actuator of
the instant invention.
[0021] FIG. 4 illustrates a force diagram for one embodiment of an
actuator of the instant invention which includes two
coaxially-mounted rotatable eccentric weights.
[0022] FIG. 5 illustartes a block diagram of one embodiment of a
microprocessor based control system used in the instant
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0023] FIG. 1 depicts one purely illustrative embodiment of a baby
bouncer system of the instant invention.
[0024] Referring to FIG. 1, resilient support frame 1 is adapted
for positioning on a relatively level surface. Cradle-like bed 2 is
attached to and supported by resilient support frame 1 in an
elevated position suitable for stable support of a baby.
Microprocessor-controlled actuator 3 can be affixed to resilient
support frame 1 through any number of known means including but not
limited to snaps, clamps, straps, detents, locks, and pins and is
engaged for the transmission of bouncing force to bounce bed 2. In
one embodiment, microprocessor-controlled actuator 3 hangs from
resilient support frame 1 and transmits bouncing forces to the
frame. Preferably, actuator 3 is attached only to the bouncing
portion of bed 2 and detects and matches the natural bouncing
frequency of resilient support frame 1. Most preferably, actuator 3
generates a gentle pull and push force at a rhythm matched to the
natural vibrating frequency of resilient support frame 1.
[0025] FIG. 2 illustrates a single eccentric weight embodiment of
an actuator of the instant invention which includes and is enclosed
and supported within housing 4. Referring to FIG. 2, DC electric
motor 5 is in electrical communication through wires 33 to
microprocessor based control system 11. DC electric motors used in
the instant invention are preferably powered by an actuator battery
pack system, a remote battery pack system, or a wall outlet
electric power-source. The power supply voltage is around twelve
volts or less, and is preferably from about 6.0 to about 7.2 volts
with an alkaline or rechargeable battery power supply.
[0026] Suitable DC electric motors which can be used in the
invention are known to those of ordinary skill in the art. DC
electric motors which can be used in the instant invention include,
but are not limited to, belt driven, coupled inline, and single
shaft DC electric motors. Preferably, the DC electric motor is
designed to operate within a range of from about 4.5 to about 7.2
volts. Specific examples of some of the DC electric motors which
can be used in actuators of the invention include but are not
limited to Mabuchi carbon brush or precision metal brush direct
current motors such as models RC260RA-18139, RC 280RA-20120 and
other equivalents.
[0027] In FIG. 2, microprocessor based control system 11: (1) is in
electrical communication with a DC power source through voltage
regulators 13; and (2) is in electrical communication through wires
35 to motion sensor 19 comprising magnetized weights 17 connected
by spring wire 15 and reed switch 21. Microprocessor based control
system 11 comprises circuitry which generates signals
representative of soothing sounds and is also in electrical
communication through wires 37 to transducer 9 for transmission of
such soothing sounds. DC electric motor 5 is connected by
mechanical linkage 7 to speed-reducing mechanism 23. Eccentric
weight 29 is mounted on rotating member 31, which is coaxially
mounted on axial shaft 27 of speed-reducing mechanism 23.
[0028] When voltage is supplied to DC electric motor 5, DC electric
motor 5 engages and rotates axial shaft 27 of speed-reducing
mechanism 23 through mechanical linkage 7, thereby causing rotating
member 31 and eccentric weight 29 to rotate and swing in a
pendulum-like rotational movement within eccentricity radius 25 and
agitate actuator housing 4.
[0029] Pulse width modulation (PWM) circuits comprising a power
transistor motor drive circuit or linear voltage regulator circuits
are preferably used to regulate the voltage supply to the DC
electric motor. Power transistor motor drive circuits which can be
used to regulate motor voltage supply include but are not limited
to Sony transistor 2SD882. Linear voltage regulator circuits which
can also be used to regulate motor voltage supply include but are
not limited to the National Semiconductor LM 317 adjustable
regulator.
[0030] Motion sensors used in actuators of the invention include
the magnet and reed switch system illustrated in FIG. 2, as well as
other motion switch systems, including but not limited to a
momentary contact motion switch, a mercury switch, and an infra-red
motion sensor.
[0031] Speed-reducing mechanisms which can be used in actuators of
the invention include but are not limited to the pulley and belt
system as illustrated in FIG. 2, as well as gear trains, frictional
wheels, chain and sprocket systems, and other known mechanical
linkage systems.
[0032] In an actuator of the invention, the DC electric motor can
engage and rotate the axial shaft of speed-reducing mechanism
through a mechanical linkage including but not limited to a belt
pulley system, a gear train, or a clutch system. The DC electric
motor can engage and rotate the axial shaft of speed-reducing
mechanism through other devices well-known to those of ordinary
skill in the art. These alternative devices include, but are not
limited to frictional wheels, etc.
[0033] Microprocessor based control system is programmed to
maintain the actuator bouncing forces at optimum values by
regulating the DC electric motor voltage supply level. The optimum
frequency for a baby bouncer system of the invention is from about
60 to about 100 times per minute (about 1 to about 1.7 Hz).
[0034] As illustrated in the flow chart of FIG. 3, the
microprocessor based control system is calibrated and regulates DC
electric motor voltage supply as follows. A microprocessor based
control system calibration switch is activated 100, tested 102, and
the microprocessor based control system sets 104 the voltage supply
Vn to the motor at a defined value (initially Vmax in this example)
and the actuator is run 106 for a period of time "t". Detected
motion sensor signal values Fn are recorded 108 during the period
of time t. Voltage is tested 110 and if voltage does not equal
minimum voltage Vmin (e.g., 40% of Vmax), Vn is adjusted 112 to
Vn+1, where Vn+1 equals Vn-"v", where "v" is a small voltage
increment which in preferred embodiments ranges from 0.1 volt to
0.5 volt, most preferably about 0.2 volts, and the actuator is
again run 106 for time period t and motion sensor signal values Fn
are again recorded 108 during the period of time t. This procedure
is repeated until Vmax is determined, within an acceptable
tolerance, to equal Vmin.
[0035] In the example illustrated in FIG. 3, Vn starts from a
"high" voltage supply level (for example, about 90% of the maximum
power supply voltage) and decreases incrementally to a "low"
voltage supply level (for example, about 40% of maximum power
supply voltage), wherein each increment of decreasing voltage level
is about -v. Alternatively, Vn starts from a "low" voltage supply
level (for example, about 40% of maximum power supply voltage) and
is increased incrementally to a "high" voltage supply level (for
example, about 90% of the maximum power supply voltage), wherein
each increment of increasing voltage level is about +v.
[0036] In preferred embodiments, the maximum power supply voltage
ranges from about 4.5 volts to about 9 volts, most preferably from
about 6 volts to about 7.2 volts for battery operation.
[0037] In preferred embodiments, the calibration running time t for
each Vn ranges from about 5 seconds to about 30 seconds, preferably
from about 10 to about 15 seconds.
[0038] In the embodiment of the invention illustrated in FIG. 3,
after Vn is tested 110 and determined 114 to equal Vmin, the
microprocessor based control system: (1) compares recorded Fn
values and determines the maximum F max value; and (2) selects and
stores 116 the voltage (V of F max) which generated the Fmax value.
The microprocessor based control system sets 118 the voltage supply
level of the DC electric motor to V of F max value and if testing
102 of the microprocessor based control system calibration switch
indicates that the switch is not activated, the DC motor continues
to run 120 at V of F max until the microprocessor based control
system is switched off or a pre-set operation time has expired.
[0039] Microprocessor based control system 11 of FIG. 2 includes a
microprocessor which comprises at least one conventional
analog-to-digital card, at least one conventional input-output
card, and a predetermined voltage supply, which may be set at a
convenient voltage such as 6 volts. FIG. 5 illustrates a block
diagram of one embodiment of a microprocessor-based electrical
control system which can be used in the instant invention.
[0040] Referring to FIG. 5, one embodiment of a
microprocessor-based electrical control system used in the
invention comprises the following components connected through
system bus circuitry 74: batteries 50, AC/DC adaptor 52, switch 72,
motion sensor 54, microprocessor 56, voice and recording integrated
circuit (IC) 58, motor drive power transistor amplification circuit
60 connected to DC motor 68 or voltage regulator 62 connected to DC
motor 68, microphone 64, and speaker 66. It will be understood that
FIG. 5 is quite simplified. For example, the details of each of
circuit portions of microprocessor 56 and voice and recording IC 58
are not shown because they are individually well known to those
skilled in the art. Further, although not shown separately in FIG.
5, input/output (I/O) pins can be included in the
microprocessor-based electrical control system for use in making
connections to external circuitry. For example, such I/O pins may
be connected more or less directly to system bus 74, or I/O pins
may be provided as part of external signaling circuitry.
[0041] Microprocessor based control systems used in actuators of
the invention may also contain voice recording and playback IC
which create, through known designs, various soothing sounds
(including music, sea wave sound, or a parent's voice message
recording). The voice recording and playback IC based control
system may be programmed to record sound through a microphone and
to emit such sounds through a transducer (such as transducer 9 of
FIG. 2) at time intervals which are coordinated with the bouncing
of the actuator. This embodiment of the invention provides a
complementary combination of soothing bouncing movement and
sound.
[0042] For example, a voice recording and playback IC such as the
Winbond ISD5108 ChipCorder could be included in a microprocessor
based control system and could be programmed with soothing sounds
such as a melody or sea wave sound; the microprocessor based
control system could also allow parents to record their own voices
messages through the microphone as well.
[0043] A wide range of microprocessors can be used in actuators of
the invention; these include but are not limited to the 8051
microprocessor made by Texas Instruments.
[0044] Referring again to FIG. 2, when eccentric weight 29 rotates
and swings in a pendulum-like rotational movement, it generates a
centrifugal force in a direction away from the center of its
rotating axis. This force will pull down or push up a bouncer seat
(not shown) when eccentric weight 29 rotates to its lowest and
highest positions, respectively. Since the centrifugal force is
always directed in a radial outward direction, when eccentric
weight 29 swings to positions other than a vertical position, a
horizontal force component is generated. When the actuator is
mounted on a baby bouncer frame, the friction between the bouncer
frame foot pads and supporting surface will balance the horizontal
component of the centrifugal force.
[0045] More than one eccentric weight can be used in actuators of
the instant invention. For example, in the twin eccentric weight
force diagram illustrated in FIG. 4, two identical eccentric
weights rotate and swing in pendulum-like rotational movements in
opposite directions and are linked by a synchronized speed
reduction mechanism. The twin eccentric weights illustrated in FIG.
4 are "mirror images" of one another along their center vertical
axis. Thus, the horizontal components of their centrifugal forces
will be balanced and result in a zero horizontal resultant force,
while the vertical force components, which actuate the vertical
bouncing motion, are not affected.
[0046] More specifically, FIG. 4 illustrates a diagram of the
forces associated with the movement of rotatable eccentric weights
A and B axially-mounted through rotational linkage 45 to a speed
reduction mechanism (such as speed reduction mechanism 23 of FIG.
2) in one embodiment of an actuator of the instant invention. The
synchronized, opposite rotations of weights A and B illustrated in
FIG. 4 generate additive downward forces A1 and B1 and additive
upward forces A3 and B3. The synchronized, opposite rotations of
weights A and B illustrated in FIG. 4 also generate canceling
horizontal forces A2 and B2. As shown in FIG. 4, the synchronized,
opposite rotations of weights A and B also generate centrifugal
forces that contribute to baby bouncer system bouncing.
[0047] A preferred embodiments of a baby bouncer system of the
invention supports a baby that weighs from about 6 to about 24
pounds, bounces the baby at a baby bouncer system frequency of
about 1 to 2 Hz, and comprises a baby bouncer seat which is
connected to an actuator of the invention wherein: the actuator is
comprised of two eccentric weights which each weigh about 50 grams
to about 300 grams; and (2) the eccentric weights each have an
eccentricity radius "Recc" which ranges from about 10 millimeters
to about 60 millimeters as the weights swing in a pendulum-like
movement when coaxially mounted on the shaft of a speed-reducing
mechanism which rotates at a speed of from about 50 to about 100
revolutions per minute.
* * * * *