JP6479397B2 - Method for dehydrating hydraulic fluid of fin stabilizer and fin stabilizer - Google Patents

Description

  The present invention relates to a fin stabilizer and a method for dehydrating hydraulic fluid of the fin stabilizer that use hydraulic fluid to reduce the roll of the hull.

  Conventionally, a fin stabilizer that reduces the roll of a ship has been proposed (see, for example, Patent Document 1). This fin stabilizer reduces and stabilizes the roll of the hull by changing the angle of the fins provided on both sides of the hull plate near the bottom of the boat. The fins are rotatably supported by rolling bearings in a housing in which a drive shaft is provided in the hull. In this fin stabilizer, the inside of the housing is filled with mineral oil as hydraulic oil supplied from a gravity tank provided in the hull, thereby lubricating the space between the drive shaft of the fin and the rolling bearing, as well as the drive shaft and housing of the fin And seal between them to prevent the ingress of seawater into the housing.

JP, 2013-203205, A

  By the way, although the fin stabilizer seals between the housing and the drive shaft of the fin by the seal ring, seawater may be mixed into the hydraulic oil from between the housing and the drive shaft of the fin. When sea water mixes in the hydraulic oil of the fin stabilizer, the rolling surface of the rolling bearing may be corroded by moisture, and the surface may be roughened to increase the rotational torque of the fin. For this reason, even if the water in the hydraulic oil of the fin stabilizer is mixed, a technique capable of efficiently removing the mixed water from the hydraulic oil is desired.

  The present invention has been made in view of such circumstances, and it is possible to efficiently reduce the water concentration in the working oil, and to prevent the failure due to the water mixed in the working oil with the fin stabilizer and the working oil of the fin stabilizer The purpose is to provide a dehydration method.

The fin stabilizer according to the present invention comprises a fin provided on a hull, a bearing for holding a drive shaft of the fin, a gravity tank for storing hydraulic oil supplied to the bearing, and a gas introduction pipe provided on the gravity tank. When the dry gas supplying unit for supplying dry燥気body to the gas inlet pipe in the gravity tank through, is provided in the gravity tank, anda gas discharge pipe for discharging the gas in the gravity tank A partition member for dividing a space volume in the gravity tank into a first space and a second space on the side containing the hydraulic oil than the first space, and the gas introduction pipe is provided in the second space The gas discharge pipe may be provided in the first space, and the partition member may have an opening communicating the first space and the second space.

  According to this configuration, even when the water that has entered the housing is dispersed in the hydraulic oil, the hydraulic oil in which the water is dispersed is supplied from the inside of the housing into the gravity tank, so the water in the hydraulic oil is It is removed by the dry gas introduced into the gravity tank. Thereby, the water | moisture content of hydraulic fluid can be removed efficiently, and the fin stabilizer which can prevent the malfunction based on the moisture mixed in hydraulic fluid is realizable.

In the fin stabilizer of the present invention, a housing in which the hydraulic fluid is enclosed, a moisture measuring device for measuring the moisture concentration of the hydraulic fluid in the housing, and the housing according to the moisture concentration measured by the moisture measuring device Control device for controlling the flow rate of the hydraulic oil supplied to the gravity tank. According to this configuration, since the flow rate of the hydraulic oil supplied to the gravity tank can be controlled according to the water concentration of the hydraulic oil in the housing, the water in the hydraulic oil can be efficiently removed.

In fin stabilizer of the present invention, the dry gas supplying unit preferably includes a water removal apparatus for producing the drying gas to dehydrate the gas. According to this configuration, since the dry gas can be produced in the hull, the dry gas to be supplied into the gravity tank can be efficiently obtained.

In the fin stabilizer of the present invention, as described above, the partition member for dividing the space volume in the gravity tank into the first space and the second space on the side containing the hydraulic oil, and the gas introduction pipe, provided in the second space, the gas discharge tube is provided in the first space, said partition member is characterized by having an opening for communicating the second space and the first space. With this configuration, the dry gas introduced from the gas introduction pipe flows toward the gas discharge pipe through the second space close to the oil surface of the hydraulic oil, so that the dry gas flows near the oil surface of the hydraulic oil. Is possible. Thus, the fin stabilizer can efficiently transfer the moisture in the hydraulic oil to the dry gas introduced into the gravity tank and discharge it as a wet gas, so that the moisture dispersed in the hydraulic oil can be efficiently removed. Become.

  Moreover, when the said hydraulic oil has biodegradable oil as a main component, it is preferable to use the fin stabilizer of this invention. When a biodegradable oil having high affinity to water is used as a hydraulic oil, it is possible to efficiently remove the water dispersed in the biodegradable oil by using the fin stabilizer of the present invention. Here, the main component means a concentration at which water in the biodegradable oil can be produced by air or nitrogen.

  Furthermore, in the fin stabilizer of the present invention that preferably uses the fin stabilizer of the present invention when the hydraulic oil contains an ester oil as a main component, the biodegradable oil preferably has an ester oil as a main component. . This configuration makes it possible to efficiently remove the water dispersed in the biodegradable oil when using a biodegradable oil having high affinity to water as the hydraulic oil. In addition, the main component here means the concentration which the water | moisture content in ester oil can produce by air or nitrogen.

The method for dehydrating hydraulic fluid of the fin stabilizer according to the present invention comprises: providing a fin provided on a hull, a bearing for holding a drive shaft of the fin, a gravity tank for storing hydraulic oil to be supplied to the bearing; a gas introduction pipe provided, the dry gas supplying unit for supplying dry燥気body to the gravity tank through the gas inlet tube, is provided in the gravity tank, gas discharge for discharging the gas in the gravity tank A partition member which comprises a pipe, and which divides a space volume in the gravity tank into a first space and a second space on the side containing the hydraulic oil than the first space, and the gas introduction pipe, Provided in the second space, the gas discharge pipe is provided in the first space, and the partition member is dehydrated of the working oil of the fin stabilizer having an opening communicating the first space and the second space. Method, And supplying the working oil to the gravity tank within the bearing holding the drive shaft of the serial fins provided housing, the water in the hydraulic oil by supplying the drying gas in the gravity tank into the drying gas The method includes the steps of: absorbing the moisture and discharging it as a wet gas to reduce the water concentration of the hydraulic oil; and supplying the hydraulic oil having a reduced water concentration in the gravity tank into the housing. .

  According to this method, even when the water that has entered the housing is dispersed in the hydraulic oil, the hydraulic oil in which the water is dispersed is supplied from the inside of the housing into the gravity tank, so the water in the hydraulic oil is Is removed by the dry gas introduced into the gravity tank. Thereby, the water | moisture content of hydraulic fluid can be removed efficiently and the dehydration method of the hydraulic fluid of the fin stabilizer which can prevent the malfunction based on the water mixed in hydraulic fluid is realizable.

  ADVANTAGE OF THE INVENTION According to this invention, the water concentration in hydraulic fluid can be reduced efficiently, and the dehydration method of the hydraulic fluid of the fin stabilizer which can prevent the malfunction based on the moisture mixed in hydraulic fluid can be implement | achieved.

FIG. 1 is a schematic perspective view of a fin stabilizer according to an embodiment of the present invention. FIG. 2 is a schematic view of a fin stabilizer according to an embodiment of the present invention. FIG. 3 is a flow diagram of a method of dehydrating hydraulic fluid of a fin stabilizer according to an embodiment of the present invention. FIG. 4A is a schematic cross-sectional view showing another example of the gravity tank according to the embodiment of the present invention. FIG. 4B is a schematic cross-sectional view showing another example of the gravity tank according to the embodiment of the present invention. FIG. 5A is a schematic plan view of a divider plate of another example of the gravity tank according to the embodiment of the present invention. FIG. 5B is a schematic plan view of a divider plate of another example of the gravity tank according to the embodiment of the present invention. FIG. 5C is a schematic plan view of a divider plate of another example of the gravity tank according to the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The present invention is not limited to the following embodiments, and can be implemented with appropriate modifications. In addition, the following embodiments can be implemented in combination as appropriate. In addition, the same reference numerals are given to constituent elements common to the respective embodiments to avoid duplication of description.

  First, with reference to FIG. 1, the outline | summary of the fin stabilizer 1 which concerns on one form of this invention is demonstrated easily. FIG. 1 is a schematic perspective view of a fin stabilizer 1 according to the present embodiment.

  As shown in FIG. 1, the fin stabilizer 1 according to the present embodiment is a device that suppresses the lateral movement of the hull 11 by changing the angle of the fins 12 in accordance with the flow of water from the front side of the hull 11. . The fin stabilizer 1 includes fins 12 provided on the left and right sides near the bottom of the hull 11. The driving shaft 12 a is attached to the rolling bearing 13 a (not shown in FIG. 1, see FIG. 2) of the housing 13. As a result, the fins 12 can be adjusted to an arbitrary angle with respect to the flow of water from the front side of the hull 11 by tilting and rotating about the drive shaft 12 a.

  Further, the fins 12 are attached to the housing 13 so as to be rotatable in the direction of the arrow X around the rotation axis (tilt cylinder) 12b. The housing 13 is rotatably installed so as to vertically penetrate the inside of the fin storage portion provided on the hull 11 from the inside of the hull to the outside of the hull. A pull-in lever 14 is connected to an upper portion of the housing 13 which projects into the inside of the hull. A hydraulic rigging cylinder 15 is connected to this lever. By expanding and contracting the rigging cylinder 15, it is possible to change the posture according to the navigation of the hull 11 by rotating the fins 12 in the front-rear direction of the hull 11 in a state in which the fins 12 project outside the boat.

  Next, the entire configuration of the fin stabilizer 1 according to the present embodiment will be described in detail. FIG. 2 is a schematic view of the fin stabilizer 1 according to the present embodiment. As shown in FIG. 2, the hull 11 is provided with a housing 13 having an accommodation space A1 inside. In the housing 13, a rolling bearing 13a is provided which holds the drive shaft 12a of the fin 12 so as to be able to tilt and rotate. Further, the housing 13 is provided with a stabilizer seal 13 b that seals between the drive shaft 12 a of the fin 12 and the housing 13. The stabilizer seal 13 b has a plurality of seal rings 13 c provided between the drive shaft 12 a of the fin 12 and the stabilizer seal 13 b. The plurality of seal rings 13c seal between the outer peripheral surface of the drive shaft 12a and the inner peripheral surface of the stabilizer seal 13b. By providing the plurality of seal rings 13 c in this manner, it is possible to prevent the infiltration of seawater or the like from the outside of the housing 13 into the housing 13. The fins 12 do not have to be attached to the rolling bearing 13a, and can be attached to various bearings.

  In the accommodation space A1 of the housing 13, the hydraulic oil 16 for lubricating the space between the drive shaft 12a of the fin 12 and the seal ring 13c of the stabilizer seal 13b is enclosed. By sealing the hydraulic oil 16 in the housing space A1 in the housing 13 as described above, the rolling bearing 13a can be lubricated to prevent an increase in rotational torque of the drive shaft 12a due to surface roughening of the rolling surface, and the housing 13, it is possible to prevent the infiltration of seawater and the like into the housing 13 from the outside.

  The hydraulic oil 16 is not particularly limited, and various lubricating oils can be used. As the hydraulic oil 16, for example, ester oils such as synthetic ester oils, various biodegradable oils such as polyglycols, and mineral oils can be used. One of these hydraulic oils 16 may be used alone, or two or more thereof may be used in combination.

  Further, in the hull 11, a gravity tank 21 for storing hydraulic oil to be supplied into the housing 13 is provided. The gravity tank 21 is provided, for example, at a position of 3 m to 6 m from the sea surface. By arranging the gravity tank 21 in this manner, it is possible to supply the hydraulic oil from the gravity tank 21 into the housing 13 by the pressure of the hydraulic oil 16 stored in the gravity tank 21.

Between the bottom 21 a of the gravity tank 21 and the bottom 13 d of the housing 13, a supply line L ₁ for supplying the hydraulic oil 16 in the gravity tank 21 from the bottom of the housing 13 into the housing 13 is provided. The supply line _{L 1,} the control valve _V 1, _{V 2} are provided for controlling the flow rate of the hydraulic fluid 16 flowing through the supply line _{L 1.} Thus, by supplying the hydraulic oil 16 into the housing 13 from the bottom of the housing 13, the foaming of the hydraulic oil 16 when the hydraulic oil 16 flows into the housing 13 can be prevented. Further, the bottom of the gravity tank 21, discharge line L ₂ for discharging the hydraulic oil 16 in the gravity tank 21 is provided. The discharge line L ₂ has a drain valve V ₃ is provided for controlling the flow rate of the hydraulic fluid 16 flowing in the discharge line L _2.

Between the bottom 13 d of the housing 13 and the central portion of the side surface 21 d of the gravity tank 21, a supply line L ₃ for supplying the hydraulic oil 16 in the housing 13 to the gravity tank 21 is provided. The supply line L _3, the hydraulic fluid pump 32 supplies the hydraulic oil 16 in the housing 13 toward the gravity tank 21, control valve V ₄ for controlling the flow rate of the hydraulic fluid 16 flowing through the supply line L _3, V _5, and the suction filter 33 is provided to remove foreign matter in the hydraulic fluid 16 flowing through the supply line L _3. Thus, from the supply line L ₃ provided in the bottom portion 13d of the housing 13 by withdrawing the hydraulic oil 16 in the housing 13, the bottom portion 13d of the housing 13 the moisture and moisture concentrations stored in the bottom portion is increased in the housing 13 The accumulated hydraulic oil 16 can be efficiently extracted out of the housing 13.

Supply line L ₃ is preferably connected to the lower the liquid level of the liquid surface near the working oil 16 in the side surface 21d of the gravity tank 21. Thus, the working oil 16 having a high concentration of water supplied from the inside of the housing 13 to the gravity tank 21 can be directly supplied to the vicinity of the liquid surface of the working oil 16 in the gravity tank 21, so that water can be efficiently removed. In addition, since the hydraulic oil 16 from within the housing 13 is supplied into the liquid of the hydraulic oil 16 stored in the gravity tank 21, the foaming of the hydraulic oil 16 can be prevented.

  Further, a moisture sensor (moisture measuring device) 34 for measuring the moisture content of the hydraulic oil in the housing 13 is provided at the bottom portion 13 d of the housing 13. The moisture sensor 34 transmits the measured moisture concentration to the control unit 35. The control unit 35 controls the flow rate of the hydraulic oil 16 supplied from the housing 13 to the gravity tank 21 via the hydraulic oil pump 32 based on the moisture concentration measured by the moisture sensor 34. Thus, the flow rate of the hydraulic oil 16 can be appropriately controlled in accordance with the concentration of water mixed in the hydraulic oil 16, so that the water in the hydraulic oil 16 can be efficiently removed.

  At the upper end portion of the side surface of the gravity tank 21, there is a gas introduction pipe 22 which communicates the outside of the gravity tank 21 with the inside of the gravity tank 21 and introduces dry gas from the outside of the gravity tank 21 to the space A2 in the gravity tank 21. It is provided. Further, the top plate 21b of the gravity tank 21 is provided with a gas discharge pipe 23 which communicates the outside of the gravity tank 21 with the inside of the gravity tank 21 and discharges the gas in the gravity tank 21 to the outside of the gravity tank 21. There is. The gas discharge pipe 23 is provided with an air breather (water removing device) 24 for removing moisture, particles, metal ions and the like in the gas. By providing the air breather 24, it is possible to prevent the moisture, particles, metal ions, etc. in the air flowing into the gravity tank 21 from the outside from being mixed in the working oil 16. The air breather 24 also has a function to lower the relative humidity of the space in the gravity tank 21 relative to the relative humidity of the hydraulic oil 16. Thus, in the fin stabilizer 1, the water concentration of the hydraulic oil 16 can be efficiently reduced.

  The dry gas is supplied from the dry gas supply unit 31 to the gas introduction pipe 22. The dry gas supply unit 31 has a moisture removing device (for example, trade name: TMR-air, manufactured by Plant Service Co., Ltd.) for dehydrating moisture in the gas to produce dry gas Supplied. The dry gas supply unit 31 absorbs the moisture in the working oil 16 by the dry gas supplied into the gravity tank 21 and discharges it as a wet gas. By supplying the dry gas to the space A2 in the gravity tank 21 through the gas introduction pipe 22 as described above, the moisture in the hydraulic oil 16 is efficiently absorbed by the dry gas and becomes a wet gas. It is possible to reduce the concentration of water inside. Further, by supplying the dry gas from the dry gas supply unit 31 provided with the water removing device, the dry gas can be produced in the hull, so that the dry gas to be supplied into the gravity tank 21 can be efficiently obtained. it can.

  The dry gas is not particularly limited as long as it can absorb the moisture in the hydraulic oil 16 and discharge it as a wet gas. For example, dry air, nitrogen, argon, etc. can be used. When the moist air of the gravity tank 21 is discharged, the gravity tank 21 may be depressurized as necessary. As a result, the water dispersed in the hydraulic oil 16 can be efficiently transferred to the dry gas.

  Next, with reference to FIG. 3, a method of dehydrating the hydraulic oil 16 in the fin stabilizer 1 according to the present embodiment will be described in detail. FIG. 3 is a flowchart of the method for dehydrating the hydraulic oil of the fin stabilizer 1 according to the present embodiment. As shown in FIG. 3, after the start of use of the fin stabilizer 1, the control unit 35 monitors the moisture concentration of the hydraulic oil 16 in the housing 13 measured by the moisture sensor 34 as needed (step ST1). Then, when the water concentration of the hydraulic oil 16 measured by the water sensor 34 is less than the predetermined threshold (step ST2: No), the control unit 35 continues the measurement of the water concentration of the hydraulic oil 16 in the housing 13 Do.

In addition, when the water concentration of the hydraulic oil 16 measured by the water sensor 34 becomes equal to or higher than the predetermined threshold (step ST2: Yes), the control unit 35 operates the inside of the housing 13 via the hydraulic oil pump 32. The oil 16 is supplied to the gravity tank 21 (step ST3). Thereby, the working oil 16 supplied to the gravity tank 21 is dewatered in contact with the drying gas supplied to the space A2 in the gravity tank 21 by the drying gas supply unit 31, and the water concentration decreases, and the water concentration reduced operating oil 16 is supplied again to the housing 13 through the supply line L _1. Thus, by circulating the hydraulic oil 16 between the housing 13 and the gravity tank 21, even if water is mixed in the housing 13 and the water concentration of the hydraulic oil 16 is increased, Since the hydraulic oil 16 whose water concentration has decreased in the tank 21 is supplied to the housing 13 as needed, it is possible to prevent the water concentration of the hydraulic oil 16 from rising.

  Subsequently, when the water concentration of the hydraulic oil 16 in the housing 13 measured by the water sensor 34 after the start of operation of the hydraulic oil pump 32 is equal to or higher than a predetermined threshold (step ST4: Yes) The operation of the hydraulic oil pump 32 is continued to remove the water in the hydraulic oil 16. In addition, when the water concentration of the hydraulic oil 16 measured by the water sensor 34 becomes less than the predetermined threshold (step ST4: No), the control unit 35 stops the hydraulic oil pump 32 (step ST5).

  As described above, according to the present embodiment, even if the water intrudes into the housing 13 and the water is dispersed in the working oil, the operation supplied from the housing 13 into the gravity tank 21 is performed. Water in the oil is removed by the dry gas introduced into the gravity tank 21. As a result, the water concentration in the working oil can be efficiently reduced, and problems due to the water mixed in the working oil can be prevented.

  Further, the fin stabilizer 1 can efficiently remove the water in the working oil even when using a biodegradable oil such as an ester oil having a high affinity for water as the working oil. Specifically, the fin stabilizer 1 can reduce the water concentration in the working oil 16 (for example, 50 ppm or less) as compared with the case of using mineral oil, and can prevent a failure based on the water mixed in the working oil.

  Here, VGP (Vessel General Permit), which was implemented in the United States by the United States Environmental Protection Agency in 2013, is for all vessels with a total length of 24.08 m or more that enter within 3 miles of the US territory including inland water. It is obligated to use biodegradable oil such as ester oil as hydraulic fluid for fin stabilizer. For this reason, in order for a ship equipped with the fin stabilizer 1 to enter within 3 miles of US territorial waters, biodegradable oil may be used as the hydraulic oil. Also in this case, as described above, the water concentration in the hydraulic oil can be kept low, and the occurrence of a problem can be suppressed. Moreover, the fin stabilizer 1 can be used also in the sea area which has a restriction | limiting in hydraulic oil by using biodegradable oil as hydraulic fluid, and the sea area which can be navigated can be expanded.

  In the embodiment described above, an example in which the hydraulic oil 16 is stored in the gravity tank 21 provided in the hull 11 has been described, but the hydraulic oil 16 can remove the water in the hydraulic oil 16 by the dry gas. If it is, various tanks other than the gravity tank 21 may be used. In the embodiment described above, the configuration of the gravity tank 21 can be changed as appropriate.

  Furthermore, in the embodiment described above, although the configuration in which the hydraulic oil is supplied from the single gravity tank 21 into the housing 13 has been described, two gravity tanks 21 are provided to operate from the respective gravity tanks 21 into the housing 13 An oil may be supplied. In this case, the biodegradable oil can be supplied from one gravity tank 21 into the housing 13 according to the sea area to be navigated, and the other gravity tank 21 operates biodegradable oil or mineral oil other than biodegradable oil. An oil may be supplied.

  4A and 4B are schematic cross-sectional views showing another example of the gravity tank 21 according to the present embodiment. As shown to FIG. 4A, the gravity tank 21 which concerns on this Embodiment has the partition plate (partition member) 25 provided substantially parallel with respect to the oil surface of the hydraulic fluid 16. As shown in FIG. The partition plate 25 divides the space A2 in the gravity tank 21 into a first space S1 and a second space S2 relatively close to the oil surface of the working oil 16 with respect to the first space S1. The partition plate 25 is provided with an opening 25a for communicating the first space S1 with the second space S2. The partition plate 25 is preferably made of, for example, a water and oil repellent material such as polytetrafluoroethylene. In the present embodiment, the partition plate 25 will be described as a plate-like member provided substantially parallel to the oil surface of the hydraulic oil 16. However, the partition plate 25 is not limited to the space A2 in the gravity tank 21. It is sufficient if it can be divided into the first space S1 and the second space S2, and it is not necessarily limited to the plate-like member.

  At the upper end portion of the side surface of the gravity tank 21, a gas introduction pipe 26 is provided which communicates the outside of the gravity tank 21 with the inside of the gravity tank 21 and introduces dry gas into the gravity tank 21 from outside the gravity tank 21. There is. The gas introduction pipe 26 is substantially L-shaped in cross section, and the tip of the gas introduction pipe 26 is in the second space S2 from the outside of the gravity tank 21 through the first space S1 and the opening 25b provided in the partition plate 25. It is arranged. Further, the gas introduction pipe 26 is disposed with the tip directed to the oil surface of the hydraulic oil 16. By arranging the gas introduction pipe 26 in this manner, the dry gas can be supplied substantially perpendicularly toward the oil surface of the hydraulic oil 16, so the moisture in the hydraulic oil 16 can be efficiently transferred to the dry gas. It becomes possible to make it a wet gas. Further, by arranging the gas introduction pipe 26 in this manner, it is possible to prevent the hydraulic oil 16 from entering the gas introduction pipe 26 even when air bubbles are generated in the hydraulic oil 16. Moreover, it is possible to change suitably arrangement | positioning of the gas introduction pipe | tube 26 in the range which produces the effect of this invention. For example, as shown in FIG. 4B, the gas introduction pipe 26 may be disposed from the outside of the gravity tank 21 toward the inside of the second space S2 so as to be substantially parallel to the oil surface of the hydraulic oil 16.

  The top plate 21 b of the gravity tank 21 is provided with a gas discharge pipe 23 which communicates the outside of the gravity tank 21 with the inside of the gravity tank 21 and discharges the gas in the gravity tank 21 to the outside of the gravity tank 21. The gas discharge pipe 23 is provided with an air breather (water removing device) 24 for removing moisture, particles and metal ions in the gas. By providing the air breather 24, it is possible to prevent moisture, particles, metal ions and the like in the air from being mixed in the working oil 16. Further, since the air breather 24 has a function to lower the relative humidity of the first space S1 and the second space S2 in the gravity tank 21 with respect to the relative humidity of the hydraulic oil 16, the water concentration of the hydraulic oil 16 is efficient. It can be reduced well.

  5A to 5C are schematic plan views of the partition plate 25 according to the present embodiment. As shown in FIGS. 5A to 5C, the shape of the partition plate 25 is not particularly limited as long as the effects of the present invention can be obtained. As the partition plate 25, one opening 25a through which the dry gas passes may be provided (see FIG. 5A), or a plurality of openings 25a may be provided (see FIG. 5B). . Moreover, as the partition plate 25, the opening 25a may be a slit or a plurality of slits (see FIG. 5C). Among these, from the viewpoint of being able to efficiently remove the moisture in the hydraulic oil 16 by the dry gas, it is preferable that the opening 25a be constituted by a plurality of slits as the opening 25a. The other configuration is the same as that of the gravity tank 21 according to the first embodiment described above, and thus the description thereof is omitted.

  In the gravity tank 21 shown in FIGS. 4 and 4B, the space A2 in the gravity tank 21 is divided into the first space S1 and the second space S2 by the partition plate 25, and the working oil 16 is separated via the gas introduction pipe 26. On the other hand, dry gas having a relatively low relative humidity is introduced into the second space S2 close to the oil surface of the hydraulic oil 16. The dry gas introduced into the second space S2 contains moisture released from the oil surface of the hydraulic oil 16 to become a wet gas, and is released to the outside of the gravity tank 21 through the opening 25a of the partition plate 25 and the air breather 24. Be done. Since the dry gas is discharged to the outside through the opening 25 a of the partition plate 25 and the air breather 24 through the vicinity of the oil surface of the hydraulic oil 16 as compared with the case where the partition plate 25 is not provided, It is possible to efficiently reduce the amount of water contained therein. Therefore, the fin stabilizer 1 which can reduce the water concentration of the hydraulic fluid 16 stored in the gravity tank 21 efficiently can be realized.

1 fin stabilizer 11 hull 12 fins 12a drive shaft 12b pivot shaft (tilt cylinder)
13 Housing 13a Rolling bearing 13b Stabilizer seal 13c Seal ring 13d Bottom part 14 Pull-in lever 15 Rigging cylinder 16 Hydraulic oil 21 Gravity tank 21a Bottom part 21b Top plate 21d Side face 22, 26 Gas introduction pipe 23 Gas discharge pipe 24 Air breather (moisture removing device)
25 Partition plate (partition member)
31 Dry gas supply unit (dry gas production device)
32 Hydraulic oil pump 33 Suction filter 34 Moisture sensor (moisture measuring device)
35 control part V ₁ , V ₂ , V ₄ , V ₅ control valve V ₃ drain valve L ₁ , L ₃ supply line L ₂ discharge line

Claims (6)

With fins provided on the hull,
A bearing for holding the drive shaft of the fin;
A gravity tank for storing hydraulic oil to be supplied to the bearing;
A gas introduction pipe provided in the gravity tank;
A drying gas supply unit for supplying dry燥気body in the gravity tank through the gas inlet tube,
A gas discharge pipe provided in the gravity tank and discharging the gas in the gravity tank;
Equipped with
A partition member that divides a space volume in the gravity tank into a first space, and a second space on the side of containing the hydraulic oil than the first space;
The gas introduction pipe is provided in the second space,
The gas discharge pipe is provided in the first space,
The fin stabilizer, wherein the partition member has an opening that communicates the first space and the second space. A housing in which the hydraulic fluid is sealed;
A moisture measuring device for measuring the moisture concentration of hydraulic oil in the housing;
The control device which controls the flow volume of the hydraulic fluid supplied to the said gravity tank from the inside of the said housing according to the water | moisture content measured by the said water | moisture content measurement apparatus, The fin stabilizer of Claim 1 provided. The drying gas supply unit has a water removal apparatus for producing the drying gas to dehydrate the gas, fin stabilizer according to claim 1 or claim 2.   The fin stabilizer according to any one of claims 1 to 3, wherein the hydraulic oil contains biodegradable oil as a main component.   The fin stabilizer according to claim 4, wherein the biodegradable oil comprises an ester oil as a main component. With fins provided on the hull,
A bearing for holding the drive shaft of the fin;
A gravity tank for storing hydraulic oil to be supplied to the bearing;
A gas introduction pipe provided in the gravity tank;
A drying gas supply unit for supplying dry燥気body in the gravity tank through the gas inlet tube,
A gas discharge pipe provided in the gravity tank and discharging the gas in the gravity tank;
Equipped with
A partition member that divides a space volume in the gravity tank into a first space, and a second space on the side of containing the hydraulic oil than the first space;
The gas introduction pipe is provided in the second space,
The gas discharge pipe is provided in the first space,
The partition member is a method of dehydrating hydraulic oil of a fin stabilizer having an opening communicating the first space and the second space,
Supplying hydraulic oil in a housing provided with a bearing for holding a drive shaft of the fin to a gravity tank;
A step of reducing the moisture concentration of the working oil discharged as the drying gas by supplying to moisture absorption of the water in the hydraulic oil to the dry gas and the wet gas in the gravity tank,
And d. Supplying the hydraulic oil having a reduced water concentration in the gravity tank into the housing.

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