Background of the Invention
1. Field of the Invention
[0001] The present invention relates to an apparatus for reducing a swinging motion of a
ship such as a rolling motion, a pitching motion and a yawing motion.
2. Description of Related Art
[0002] Japanese Patent No.
3,556,857 discloses a swinging motion reducing apparatus for reducing rolling, pitching and
yawing motions of a ship. The swinging motion reducing apparatus includes a motor,
a flywheel that is driven by the motor, a gimbal mechanism that contains the flywheel,
a support section for movably supporting the gimbal mechanism, a frictional damper
for controlling a motion of the gimbal mechanism, a power supply for supplying electric
power to the motor, and a control section. When the gimbal mechanism rolls at a predetermined
angle or more, the control section controls such that the power supply to the motor
is stopped to prevent the swinging motion reducing apparatus from being damaged because
of the motion of the gimbal mechanism exceeding a limitation of the specification.
US 5628267 discloses a swinging motion reducing apparatus designed to overcome overheating of
the bearings.
Summary of the Invention
[0003] An object of the present invention is to prevent a swinging motion reducing apparatus
for a ship from being damaged.
[0004] In an aspect of the present invention, a swing motion reducing apparatus for a ship
includes a flywheel, a gimbal mechanism configured to rotatably support the flywheel,
a motor configured to rotate the flywheel based on a drive power to be supplied; and
a motor driver configured to supply the drive power to the motor. A damper section
is configured to brake a swing motion of the gimbal mechanism. A safety unit controls
the motor driver to stop the supply of the drive power to the motor when a temperature
of the damper section is equal to or higher than a predetermined temperature.
[0005] According to the present invention, damage of a swinging motion reducing apparatus
for a ship is prevented.
Brief Description of the Drawings
[0006]
FIG. 1 is a diagram schematically showing a swinging motion reducing apparatus for
a ship according to a first embodiment of the present invention;
FIG. 2 is a cross-section view of the swinging motion reducing apparatus body; and
FIG. 3 is a diagram schematically showing the swinging motion reducing apparatus according
to a second embodiment of the present invention.
Description of the Embodiments
[0007] Hereinafter, a swinging motion reducing apparatus for a ship according to the present
invention will be described with reference to the attached drawings.
[First Embodiment]
[0008] As shown in FIG. 1, a swinging motion reducing apparatus according to a first embodiment
of the present invention includes a swinging motion reducing apparatus body 10, a
motor driver 20, a generator 30, and a safety unit 40. The swinging motion reducing
apparatus body 10 includes a motor 13, a damper 15A, and a damper 15B. The generator
30 and the motor 13 are a 3-phase generator and a 3-phase motor, respectively. The
motor driver 20 includes an input terminal 21, an output terminal 22, a CM terminal
23, an X1 terminal 24, and a relay 25. The input terminal 21 includes an R terminal,
an S terminal, and a T terminal. The output terminal 22 includes a U terminal, a V
terminal, and a W terminal. The relay 25 is provided between the input terminal 21
and the output terminal 22. The relay 25 opens and closes a connection between the
R terminal and the U terminal, a connection between the S terminal and the V terminal,
and a connection between the T terminal and the W terminal. The input terminal 21
is connected to the generator 30 via a breaker switch 31. The output terminal 22 is
connected to a power cable 13a of the motor 13.
[0009] The safety unit 40 includes a bimetal switch 41A provided for the damper 15A and
a bimetal switch 41B provided for the damper 15B. The bimetal switches 41A and 41B
are in a close state initially, and monitor temperatures of the dampers 15A and 15B,
respectively. The bimetal switch 41A opens to set an OFF state when a temperature
of the damper 15A increase to a temperature equal to or higher than a predetermined
temperature. The bimetal switch 41B opens to set an OFF state when the temperature
of the damper 15B increase to a temperature equal to or higher than a predetermined
temperature. The CM terminal 23 is connected to the X1 terminal 24 via the bimetal
switches 41A and 41B. Since the bimetal switches 41A and 41B are connected to each
other in series, the connection between the CM terminal 23 and the X1 terminal 24
is in an ON state (a conduction state) when both of the bimetal switches 41A and 41B
close, and the connection between the CM terminal 23 and the X1 terminal 24 is in
an OFF state (a non-conduction state) when at least one of the bimetal switches 41A
and 41B opens.
[0010] The relay 25 turns the connection between the input terminal 21 and the output terminal
22 to be in the ON state (closes the connection between the input terminal 21 and
the output terminal 22) when the connection between the CM terminal 23 and the X1
terminal 24 is in the ON state. Also, the relay 25 turns the connection between the
input terminal 21 and the output terminal 22 to be in the OFF state (opens the connection
between the input terminal 21 and the output terminal 22) when the connection between
the CM terminal 23 and the X1 terminal 24 is in the OFF state.
[0011] The motor driver 20 supplies a drive power to the motor 13 when the relay 25 keeps
the connection between the input terminal 21 and the output terminal 22 in the ON
state, and stops the supply of the drive power when the relay 25 turns the connection
between the input terminal 21 and the output terminal 22 to be in the OFF state.
[0012] As shown in FIG. 2, the swinging motion reducing apparatus body 10 includes the flywheel
11, the gimbal mechanism 12, the motor 13, a gimbal mechanism support section 14,
and the dampers 15A and 15B. The gimbal mechanism 12 supports the flywheel 11 so that
the flywheel 11 can rotate around a rotation axis S1. The motor 13 drives the flywheel
11. The gimbal mechanism support section 14 supports the gimbal mechanism 12 so that
the gimbal mechanism 12 can swing around a swing axis S2. Each of the dampers 15A
and 15B brakes the swinging motion of the gimbal mechanism 12 with a fluid resistance
of a hydraulic oil. For example, the dampers 15A and 15B are rotary dampers. The swing
axis S2 is orthogonal to the rotation axis S1. The gimbal mechanism support section
14 is fixed to a hull. The bimetal switches 41A and 41B are attached to the outer
sides of the dampers 15A and 15B, respectively.
[0013] A principle that the swinging motion reducing apparatus according to the present
embodiment reduces the swinging motion of a ship will be described by exemplifying
a case that a left or right direction axis (Pitch axis) of the hull is parallel to
the swing axis S2. The flywheel 11 is driven by the motor 13 at a high speed so as
to have angular momentum H. When the hull receives a wave in a direction of a roll
axis to roll at an angular velocity Q, a gyrotorque T1 represented by an exterior
product of the angular momentum H and the angular velocity Ω acts to the gimbal mechanism
12, and the gimbal mechanism 12 rolls around the swing axis S2. At this time, since
the flywheel 11 works to maintain the angular momentum H, a counter torque T2 acts
to the hull via the gimbal mechanism support section 14. When an angular velocity
of the swinging motion of the gimbal mechanism 12 is ω, the counter torque T2 is represented
by an exterior product of the angular momentum H and the angular velocity ω. Because
the counter torque T2 acts to a direction opposite to the roll direction of the hull,
the rolling motion in the roll direction of the hull is reduced.
[0014] For example, when the swinging motion reducing apparatus is used under an overload
circumstance such as a case where a ship having the swinging motion reducing apparatus
according to the present embodiment sails a high wave area, the gimbal mechanism 12
heavily swings so that the temperatures of the dampers 15A and 15B become high, and
thus a seal member for sealing the hydraulic oil may be damaged. Since the gimbal
mechanism 12 cannot be broken when the hydraulic oil leaks, the swinging motion reducing
apparatus may be damaged.
[0015] Referring to FIG. 1, when the temperature of the damper 15A increases the predetermined
temperature or more, the bimetal switch 41A opens to turn the connection between the
CM terminal 23 and the X1 terminal 24 to be in the OFF state. Then, since the relay
25 turns the connection between the input terminal 21 and the output terminal 22 to
be in the OFF state, the motor driver 20 automatically stops the supply of the drive
power. Also, when the temperature of the damper 15B increases the predetermined temperature
or more, the motor driver 20 automatically stops the supply of the drive power in
the same manner as that of the damper 15A. That is, the safety unit 40 stops the supply
of the drive power to the motor driver 20 when at least one of the dampers 15A and
15B exceeds the predetermined temperature. In this manner, the swinging motion reducing
apparatus body 10 safely stops and the dampers 15A and 15B can be prevented from being
damaged.
[0016] Additionally, in case of occurrence of a failure of the damper 15A or 15B, the temperatures
of the damper 15A or 15B becomes high. The present embodiment prevents the swinging
motion reducing apparatus from continuing to operate under the condition of occurrence
of the failure of the damper 15A or 15B. Accordingly, the damage of the damper 15A
or 15B can be prevented and the damage of the swinging motion reducing apparatus body
10 is prevented.
[0017] Moreover, when an atmosphere temperature around the swinging motion reducing apparatus
body 10 is high, the damper 15A or 15B cannot release the heat to circumference, and
accordingly a braking performance of the damper 15A or 15B deteriorates. When the
swinging motion reducing apparatus continues to operate in a state that the braking
performance of the damper 15A or 15B deteriorates, the swinging motion reducing apparatus
body 10 may be damaged. According to the present embodiment, since the swinging motion
reducing apparatus is stopped in the case of a high atmosphere temperature, the damage
of the swinging motion reducing apparatus body 10 can be prevented.
[0018] Since the bimetal switches 41A and 41B are respectively arranged on the outer sides
of the dampers 15A and 15B, the swinging motion reducing apparatus can be easily assembled.
Meanwhile, the bimetal switches 41A and 41B may be arranged in the dampers 15A and
15B, respectively.
[Second Embodiment]
[0019] Referring to FIG. 3, the swinging motion reducing apparatus for a ship according
to a second embodiment of the present invention will be described. The swinging motion
reducing apparatus according to the second embodiment of the present invention is
configured by replacing the safety unit 40 in the first embodiment with a safety unit
50. The safety unit 50 includes temperature sensors 51A and 51B such as a thermocouple
or a thermistor, and a determining section 52. The temperature sensors 51A and 51B
are provided for the dampers 15A and 15B, respectively. The temperature sensor 51A
monitors a temperature of the damper 15A and outputs a signal indicating the temperature
of the damper 15A to the determining section 52. The temperature sensor 51B monitors
a temperature of the damper 15B and outputs a signal indicating the temperature of
the damper 15B to the determining section 52. The determining section 52 is connected
to the CM terminal 23 and the X1 terminal 24, respectively. The determining section
52 determines whether or not the temperatures indicated by the signals sent from the
temperature sensors 51A and 51B are higher than a predetermined temperature. When
both of the signal sent from the temperature sensor 51A and the signal sent from the
temperature sensor 51B indicate a temperature lower than the predetermined temperature,
the determining section 52 turns the connection between the CM terminal 23 and the
X1 terminal 24 to be in the ON state. When the temperature indicated by at least one
of the signal sent from the temperature sensor 51A and the signal sent from the temperature
sensor 51B exceeds the predetermined temperature, the determining section 52 turns
the connection between the CM terminal 23 and the X1 terminal 24 to be in the OFF
state. Accordingly, when at least one of the dampers 15A and 15B exceeds the predetermined
temperature, the safety unit 50 stops the supply of the drive power to the motor 13.
[0020] When the temperature sensors 51A and 51B are arranged on the outer sides of the dampers
15A and 15B, the swinging motion reducing apparatus can be easily assembled. Meanwhile,
the temperature sensors 51A and 51B may be arranged in the dampers 15A and 15B, respectively.
[0021] In the above-mentioned respective embodiments, the generator 30 and the motor 13
may be a single-phase generator and a single-phase motor, respectively. In addition,
the dampers 15A and 15B may be a frictional damper, a linear damper, or a hydraulic
pump.
1. A swing motion reducing apparatus (10) for a ship comprising:
a flywheel (11) ;
a gimbal mechanism (12) configured to rotatably support said flywheel (11);
a motor (13) configured to rotate said flywheel (11) based on a drive power to be
supplied;
a motor driver (20) configured to supply the drive power to said motor (13);
characterized by comprising a first and a second damper (15A, 15B) configured to brake a swing motion
of said gimbal mechanism (12); and
a safety unit (40) configured to control said motor driver to stop the supply of the
drive power to said motor (13) when a temperature of at least one of said first and
second damper (15A, 15B) is equal to or higher than a predetermined temperature.
2. The swing motion reducing apparatus according to claim 1, wherein said motor driver
comprises first and second terminals (21, 22),
wherein said safety unit (40) comprises a path from said first terminal (21) to said
second terminal (22), and
said motor driver (20) supplies the drive power to said motor (13) when said path
is in an ON state, and stops the supply of the drive power to said motor when said
path is in an OFF state.
3. The swing motion reducing apparatus according to claim 2, wherein
said safety unit (40) comprises a first bimetal switch (41A) provided for said first
damper (15A) in said path, and
said first bimetal switch sets said path to the ON state when the temperature of said
first damper (15A) is lower than the predetermined temperature and sets said path
to the OFF state when the temperature of said first damper (15A) is equal to or higher
than the predetermined temperature.
4. The swing motion reducing apparatus according to claim 3,
wherein said safety unit (40) further comprises a second bimetal switch (41B) provided
for said second damper (15B) in said path and connected with said first bimetal (15A)
switch in series, and
said second bimetal switch (41B) sets said path to the ON state when the temperature
of said second damper (15B) is lower than the predetermined temperature and sets said
path to the OFF state when the temperature of said second damper (15B) is equal to
or higher than the predetermined temperature.
5. The swing motion reducing apparatus according to claim 2, wherein
said safety unit (40) further comprises:
first and second temperature sensors (51A, 51B) provided for said first and second
dampers (15A, 15B) to detect temperatures of said first and second dampers (15A, 15B),
respectively; and
a determining section (52) sets said path to the ON state, when both of temperatures
detected by said first and second temperature sensors (51A, 51B) are lower than the
predetermined temperature, and sets said path to the OFF state, when at least one
of temperatures detected by said first and second temperature sensors (51A, 51B) is
equal to or higher than the predetermined temperature.
1. Schaukelbewegungs-Reduzierungsvorrichtung (10) für ein Schiff, umfassend:
- ein Schwungrad (11);
- einen Kardanmechanismus (12), der so ausgelegt ist, dass er das Schwungrad (11)
drehbar lagern kann;
- einen Motor (13), der so ausgelegt ist, dass er das Schwungrad (11) aufgrund einer
zu liefernden Antriebskraft drehen kann;
- einen motorischen Antrieb (20), der so ausgelegt ist, dass er die Antriebskraft
für den Motor (13) liefern kann;
dadurch gekennzeichnet, dass sie einen ersten und einen zweiten Schwingungsdämpfer (15A, 15B) umfasst, der so
ausgelegt ist, dass eine Schaukelbewegung des Kardanmechanismus (12) abgebremst werden
kann; und
- eine Sicherungseinheit (40), die so ausgelegt ist, dass sie den motorischen Antrieb
steuern kann, um die Lieferung der Antriebskraft an den Motor (13) zu stoppen, wenn
zumindest einer der beiden Schwingungsdämpfer (15A, 15B) eine Temperatur aufweist,
die einer vorgegebenen Temperatur entspricht oder höher als diese ist.
2. Schaukelbewegungs-Reduzierungsvorrichtung nach Anspruch 1, wobei der motorische Antrieb
einen ersten und einen zweiten Anschluss (21, 22) umfasst,
wobei die Sicherungseinheit (40) eine Strecke von dem ersten Anschluss (21) zu dem
zweiten Anschluss (22) umfasst, und
der motorische Antrieb (20) den Motor (13) mit der Antriebskraft beliefert, wenn sich
die Strecke im Zustand EIN befindet und die Belieferung der Antriebskraft an den Motor
stoppt, wenn sich die Strecke im Zustand AUS befindet.
3. Schaukelbewegungs-Reduzierungsvorrichtung nach Anspruch 2, wobei die Sicherungseinheit
(40) einen ersten Bimetallschalter (41A) umfasst, der für den ersten Schwingungsdämpfer
(15A) auf der Strecke vorgesehen ist, und der erste Bimetallschalter die Strecke in
den Zustand EIN schaltet, wenn die Temperatur des ersten Schwingungsdämpfers (15A)
niedriger als die vorgegebene Temperatur ist, und die Strecke in den Zustand AUS schaltet,
wenn die Temperatur des ersten Schwingungsdämpfers (15A) gleich oder höher als die
vorgegebene Temperatur ist.
4. Schaukelbewegungs-Reduzierungsvorrichtung nach Anspruch 3, wobei die Sicherungseinheit
(40) weiterhin einen zweiten Bimetallschalter (41B) umfasst, der für den zweiten Schwingungsdämpfer
(15B) auf der Strecke vorgesehen ist und mit dem ersten Bimetall-Schalter (15A) in
Reihe geschaltet ist, und
der zweite Bimetallschalter (41B) die Strecke in den Zustand EIN schaltet, wenn die
Temperatur des zweiten Schwingungsdämpfers (15B) niedriger als die vorgegebene Temperatur
ist und die Strecke in den Zustand AUS schaltet, wenn die Temperatur des zweiten Schwingungsdämpfers
(15B) gleich oder höher als die vorgegebene Temperatur ist.
5. Schaukelbewegungs-Reduzierungsvorrichtung nach Anspruch 2, wobei die Sicherungseinheit
(40) weiterhin umfasst:
einen ersten und einen zweiten für den ersten und den zweiten Schwingungsdämpfer (15A,
15B) vorgesehenen Temperatursensor (51A, 51B), um Temperaturen des ersten bzw. des
zweiten Schwingungsdämpfers (15A, 15B) zu detektieren und ein Festlegungsabschnitt
(52) die Strecke in den Zustand EIN schaltet, wenn beide von dem ersten und dem zweiten
Temperatursensor (51A, 51B) detektierte Temperaturen niedriger als die vorgegebene
Temperatur sind, und die Strecke in den Zustand AUS schaltet, wenn zumindest eine
von dem ersten und dem zweiten Temperatursensor (51A, 51B) detektierte Temperatur
gleich oder höher als die vorgegebene Temperatur ist.
1. Appareil (10) de réduction des mouvements de balancement pour navires, comprenant
:
un volant (11) ;
un mécanisme à cardan (12) agencé pour supporter ledit volant (11) en rotation ;
un moteur (13) agencé pour entraîner ledit volant (11) en rotation sur la base d'une
puissance devant être fournie ;
un actionneur motorisé (20) agencé pour assurer l'approvisionnement
en puissance dudit moteur (13) ;
caractérisé en ce qu'il comporte un premier et un second amortisseur (15A, 15B) pour freiner un mouvement
de balancement dudit mécanisme à cardan (12) ; et
une unité de sécurité (40) agencée pour commander ledit actionneur motorisé pour arrêter
l'alimentation en puissance fournie par l'actionneur audit moteur (13) lorsque la
température d'au moins un desdits premier et second amortisseur (15A, 15B) est égale
ou supérieure à une température prédéterminée.
2. Appareil de réduction des mouvements de balancement selon la revendication 1, dans
lequel l'actionneur motorisé comprend des premières et des secondes bornes (21, 22),
dans lequel ladite unité de sécurité (40) comporte un circuit allant desdites premières
bornes (21) auxdites secondes bornes (22), et
ledit actionneur motorisé (20) alimente en puissance d'entraînement ledit moteur (13)
lorsque ledit circuit est dans l'état ouvert et arrête l'alimentation dudit moteur
lorsque ledit circuit est dans l'état fermé.
3. Appareil de réduction des mouvements de balancement selon la revendication 2, dans
lequel
ladite unité de sécurité (40) comporte un premier interrupteur bimétallique (41A)
affecté audit premier amortisseur (15A) dans ledit circuit, et
ledit premier interrupteur bimétallique fait passer ledit circuit dans l'état ouvert
lorsque la température dudit premier amortisseur (15A) est inférieure à la température
prédéterminée et fait passer ledit circuit dans l'état fermé, lorsque la température
dudit premier amortisseur (15A) est égale ou supérieure à la température prédéterminée.
4. Appareil de réduction des mouvements de balancement selon la revendication 3,
dans lequel ladite unité de sécurité (40) comporte en outre un second interrupteur
bimétallique (41 B) affecté audit second amortisseur (15B) dans ledit circuit, et
connecté en série audit premier interrupteur bimétallique (41 A), et
ledit second interrupteur bimétallique (41 B) fait passer ledit circuit dans l'état
ouvert lorsque la température dudit second amortisseur (15B) est inférieure à la température
prédéterminée et fait passer ledit circuit dans l'état fermé, lorsque la température
dudit second amortisseur (15B) est égale ou supérieure à la température prédéterminée.
5. Appareil de réduction des mouvements de balancement selon la revendication 2, dans
lequel
ladite unité de sécurité (40) comporte en outre des premiers et des seconds capteurs
(51A, 51 B), affectés audit premier et audit second amortisseurs (15A, 15B) pour détecter
les températures respectives dudit premier et dudit second amortisseurs (15A, 15B),
et
une section décisionnelle (52) qui fait passer ledit circuit dans l'état ouvert lorsque
les deux températures détectées par ledit premier et ledit second capteurs (51A, 51
B) sont inférieures à la température prédéterminée, et qui fait passer ledit circuit
dans l'état fermé lorsqu'au moins une des deux températures détectées par ledit premier
et ledit second capteurs (51A, 51 B) est égale ou supérieure à la température prédéterminée.