JP4891031B2 - Valve drive actuator - Google Patents

Description

  The present invention relates to a valve drive actuator that is disposed in a liquid and that opens and closes a valve.

  In general, a cargo ship is provided with a plurality of ballast tanks for supplying and draining ballast water and adjusting buoyancy. Each ballast tank is supplied with ballast water when no cargo such as crude oil is loaded, and when cargo is loaded. The hull is stabilized by draining ballast water.

  Ballast water is used by taking seawater at a port, etc., and is supplied or drained to each ballast tank from a seawater intake through a trunk pipe and a branch pipe branched from the seawater. By individually opening and closing, each ballast tank is supplied or drained.

  In many cases, the trunk pipe and the branch pipe are disposed in the ballast tank so as not to impair the cargo loading space. In this case, a valve provided in the branch pipe in each ballast tank and the valve are provided in the ballast tank. A valve driving actuator for opening and closing the valve is also disposed. This valve drive actuator often employs hydraulic drive by a hydraulic cylinder, but the oil leaks into the ballast tank and may contaminate seawater as ballast water. Adoption of an actuator for driving a valve is demanded.

  However, in order to use an electrically driven valve drive actuator in the water, it is necessary to prevent water from entering into electrical parts such as a motor. Since it cannot be easily pulled out of the water, higher waterproofness is required.

  As such a valve drive actuator that is disposed in water and drives the valve to open and close, for example, Patent Document 1 discloses a valve drive actuator in which a motor is housed in a casing and water is prevented from entering the casing. Disclosure.

The valve driving actuator (driving unit) of Patent Document 1 is disposed in water to open and close the valve body, and the motor is housed in a casing composed of a base and a cover. Furthermore, the portion of the base through which the valve plate drive shaft and the cable pass is sealed, and a partition plate is assembled to the base to form a pressurized air chamber between the base and the partition plate, thereby providing a casing. Preventing inundation inside.
JP-A-6-288484 (paragraph numbers 0005 and 0006)

  However, as in Patent Document 1, the structure in which the partition plate is assembled along the wall surface of the casing to form an air chamber for preventing inundation has a large valve drive actuator for the partition plate and the air chamber. Easy to convert.

  It is an object of the present invention to provide a valve drive actuator that can prevent immersion when placed in a liquid such as water and can be downsized.

  In order to achieve the above object, a valve driving actuator according to the present invention is arranged in a liquid for opening and closing a valve, and includes a motor for supplying a driving force for opening and closing the valve, and the motor. And an output shaft for outputting the driving force of the motor to the outside of the casing. Furthermore, the internal space of the casing is divided into an inner chamber and an outer chamber surrounding the inner chamber, and a primary liquid stop structure that prevents immersion from the outside of the casing to the outer chamber, and from the outer chamber to the inner chamber A secondary liquid stop structure for preventing immersion liquid is provided, and a sensor for detecting immersion liquid in the casing is provided in the outer chamber.

  According to the above configuration, since the internal space of the casing is divided into the inner chamber and the outer chamber surrounding the inner chamber, even if the liquid is temporarily immersed in the casing from a portion through which the output shaft penetrates, the liquid is first removed. It is possible to delay the accumulation in the chamber and the further immersion from there into the inner chamber. As a result, the immersion of liquid-sensitive components such as electrical components arranged in the inner chamber can be sufficiently delayed, and a sensor such as a leak sensor provided in the outer chamber detects the immersion of the casing. Therefore, it is possible to detect the liquid accumulated in the outer chamber before it is immersed in the inner chamber.

  Furthermore, since the outer chamber is provided so as to surround the inner chamber, in addition to the through-hole portion of the output shaft, the liquid immersed from all parts such as the cable-piercing portion and the assembled casing connection portion can be stored in the outer chamber. In addition, since a dedicated air chamber for preventing immersion liquid can be dispensed with, the valve drive actuator can be reduced in size by omitting the air chamber and the partition plate.

  In addition, the inner chamber is divided into a plurality of compartments, and a tertiary liquid stop structure is provided to prevent liquid from entering and exiting between the compartments, and an electric cable is routed through the partition walls separating the compartments. It is also possible to lengthen the time until the liquid is immersed in the compartment in order along the wiring direction of the electric cable.

  According to this configuration, direct immersion liquid from the outer chamber to some of the compartments of the inner chamber is prevented, and the partial compartment is immersed only from other compartments through the penetration portion of the electric cable. Therefore, the immersion liquid can be delayed in order along the electric cable, and the immersion of the liquid can be more reliably prevented as the component is weak against the liquid. In other words, the penetration part of the electric cable is a part that is relatively easier to immerse than other parts, but since the electric cable is routed through the partition wall that separates the compartments, the electric cable is routed from the other compartments. The wired compartment can delay the immersion liquid, compared to the case of direct wiring from the outer chamber.

  Although all components that are vulnerable to liquids such as electrical parts can be arranged in the inner chamber, the motor of the electrical parts may be arranged in the outer chamber so that the space in the outer chamber can be used effectively. In this case, if the motor is attached to the partition wall that partitions the inner chamber and the outer chamber and placed in the outer chamber, and the electrical cable wired to the inner chamber is electrically connected through the partition wall, the motor is placed in the outer chamber. However, it is possible to prevent immersion in the wiring portion that is weak to the liquid.

  As is apparent from the above description, according to the present invention, the internal space of the casing is divided into an inner chamber and an outer chamber surrounding the inner chamber, and the liquid immersed in the casing is first stored in the outer chamber, and the sensor is used as a sensor. Therefore, it is possible to prevent immersion of liquid-sensitive parts such as electrical parts arranged in the inner chamber, and to reduce the size of the valve driving actuator.

  Hereinafter, embodiments of a valve drive actuator according to the present invention will be described with reference to the drawings. FIG. 1 is a piping diagram for water supply / drainage of a ballast tank provided with a valve drive actuator according to the present invention, and FIG. 2 is a schematic view showing the valve drive actuator.

  The valve drive actuator 1 is for opening and closing a water supply / drainage pipe of a ballast tank 2 of a cargo ship, for example, and is provided on a branch pipe 4 branched from a trunk pipe 3 passing through the inside of a plurality of ballast tanks 2. The valves 5 are individually opened and closed, and are arranged inside each ballast tank 2 so as to supply and discharge ballast water for each ballast tank 2.

  The valve driving actuator 1 includes a motor 6 that supplies a driving force for opening and closing the valve 5, a casing 7 that houses the motor 6, an output shaft 8 that outputs the driving force of the motor 6 to the outside of the casing 7, and a casing. 7 and a sensor 9 for detecting water intrusion, and the inner space of the casing 7 is divided into an inner chamber 10 and a sensor chamber 11 as an outer chamber surrounding the inner chamber 10 and arranging the sensor 9. In addition, a primary water stop structure that prevents water from entering the sensor chamber 11 from the outside of the casing 7 and a secondary water stop structure that prevents water from entering the inner chamber 10 from the sensor chamber 11 are provided. The inner chamber 10 is divided into a switch chamber 12, a gear chamber 13, and a condenser chamber 14 as a branch chamber, and a third water stop structure is provided to prevent water from entering and leaving the branch chamber.

The motor 6 is disposed in the sensor chamber 11 and is attached to a portion of the partition wall 15 that partitions the inner chamber 10 and the sensor chamber 11 that partitions the sensor chamber 11 and the gear chamber 13. A rotating shaft 16 penetrating to the side 13 is arranged in the gear chamber 13 and rotates a gear 17 for transmitting the rotation of the motor 6 to the output shaft 8.

  The wiring 6 a of the motor 6 penetrates the partition wall 15 toward the gear chamber 13 and is electrically connected from the sensor chamber 11 to the electric cable 18 that runs through the partition wall 15 and is wired to the gear chamber 13. Further, by sealing the resin at the boundary between the motor 6 and the partition wall 15, the periphery of the rotating shaft 16 and the wiring 6a of the motor 6 penetrating the partition wall 15 is sealed and the motor 6 is positioned reliably.

  The electric cable 18 is connected to an external AC power supply 20 through an underwater connector 19, and is connected to the sensor 9 disposed in the sensor chamber 11 through the casing 7, and further through the partition wall 15. Then, the switch chambers 12 are connected to the switches 21a and 21b for detecting the opening / closing position of the valve 5 and connected to the motor 6 from the inside of the gear chamber 13 through the partition wall 15 to separate the compartments from each other. The partition walls 22 a and 22 b pass through the partition wall 22 a that separates the gear chamber 13 and the capacitor chamber 14, and are connected to the capacitor 23 inside the capacitor chamber 14.

  The casing 7 is formed by covering the upper opening of the container-like base 24 opened upward with a cover-like container-like cover 25 and forming a bearing 26 for receiving the output shaft 8 so as to penetrate the bottom. Yes. A circular hole is formed in the top of the casing 7 to fit an indicator 27 indicating the rotation angle of the output shaft 8, and this indicator 27 is connected to the upper end of the output shaft 8 via a connecting shaft 28. The connecting shaft 28 passes through the switch chamber 12 and is provided with a cam (not shown) for turning on and off the switches 21 a and 21 b at a portion passing through the switch chamber 12.

  Next, the operation of the valve drive actuator 1 will be described. FIG. 3 is an electric circuit diagram of the valve driving actuator.

  First, by switching the external operation switch 29 from “stop” to “open”, the current from the AC power source 20 passes through the wiring 30a and is converted to DC by the capacitor 23, and the rotating shaft 16 of the motor 6 is opened. Rotate to

  The rotation of the rotating shaft 16 of the motor 6 is transmitted to the worm shaft 31 and the worm wheel 32 via the gear 17, and is transmitted to the drive shaft 8 while decelerating by the worm shaft 31 and worm wheel 32 to open the valve 5. Drive in the direction. When the opening position of the valve 5 reaches the upper limit, the cam of the connecting shaft 28 turns off the switch 21a interposed in the wiring 30a and stops the driving of the valve 5. The switch 21a is normally on except when the opening position of the valve 5 is the upper limit.

  Further, by switching the external operation switch 29 to “closed”, the current of the AC power supply 20 passes through the wiring 30 b and is converted to DC by the capacitor 23, thereby rotating the rotating shaft 16 of the motor 6 in the closing direction. The operation in this closing direction drive is the same as that in the opening direction driving except that the current passes through the wiring 30b and the switch 21b and the rotation direction of each rotating member from the motor 6 to the valve 5 is opposite. It is.

  The worm shaft 31 is connected to a handle 33 provided so as to penetrate the casing 7 in and out, so that the output shaft 8 can be manually rotated. In FIG. 3, 34 is a terminal block, 35 is a thermal protector, and 36 is a fuse.

  Here, the water stop function of the valve drive actuator 1 will be described. First, the primary water stop structure prevents water from entering the casing 7 from the outside, and delays water in the casing 7 itself. The primary water stop structure includes a gap between the output shaft 8 and the bearing 26, a through portion of the electric cable 18, a gap between the indicator 27 and the circular hole, a through portion of the handle 33, and a connecting portion between the base 24 and the cover 25. O-ring, sheet packing, cable clamp 37, potting process, sheet gasket, etc. can be adopted.

  Next, the water immersed in the casing 7 is stored in the sensor chamber 11 so as not to be immediately immersed in the inner chamber 10. Moreover, even if a certain amount of water accumulates in the sensor chamber 11, the secondary water stop structure prevents water from entering the inner chamber 10 from the sensor chamber 11 and delays water intrusion into the inner chamber 10. The secondary water stop structure is a through portion of the worm shaft 31 or a through portion of the electric cable 18, and the same structure as the primary water stop structure can be adopted.

  Further, when the sensor 9 detects the water stored in the sensor chamber 11, before the water in the sensor chamber 11 is submerged in the inner chamber 10, an abnormal water output is output. The sensor 9 is a water leakage sensor or the like.

  Further, in the inner chamber 10, the capacitor chamber 14 is not directly submerged from the sensor chamber 11, but is once submerged in the gear chamber 13 and then submerged in the capacitor chamber 14 along the electric cable 18. The time to reach is the longest.

  According to the above configuration, since the internal space of the casing 7 is divided into the inner chamber 10 and the sensor chamber 11, even if the casing 7 is submerged, the wiring 6a of the motor 6 disposed in the inner chamber 10 and the switch 21a, It is possible to sufficiently delay the inundation of water-sensitive parts such as 21b and condenser 23. Moreover, since the inner chamber 10 is divided into the switch chamber 12, the gear chamber 13, and the capacitor chamber 14, even if the inner chamber 10 is immersed in the gear chamber 13, for example, it is possible to prevent the capacitor chamber 14 from being immersed therein.

  Further, since the sensor 9 arranged in the sensor chamber 11 detects water intrusion into the casing 7, a signal such as a caution or warning is issued before the water is infused into the inner chamber 10, and water is pumped out or manual operation by the handle 33 is performed. Can be switched.

  In addition, this invention is not limited to said embodiment, A change can be suitably added within the scope of the present invention. For example, the valve drive actuator 1 can be used not only by being placed in water such as ballast water but also by being placed in a liquid other than water.

Plumbing diagram for water supply and drainage of ballast tank provided with valve drive actuator according to the present invention Schematic diagram showing the valve drive actuator Electric circuit diagram of valve drive actuator

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve drive actuator 6 Motor 7 Casing 8 Output shaft 9 Sensor 10 Inner chamber 11 Sensor chamber 12 Switch chamber 13 Gear chamber 14 Capacitor chamber 15 Partition wall 18 Electric cable

Claims (2)

A valve driving actuator arranged in the liquid to open and close the valve;
A motor that supplies a driving force for opening and closing the valve; a casing that houses the motor; and an output shaft that outputs the driving force of the motor to the outside of the casing;
An internal space of the casing is divided into an inner chamber and an outer chamber that surrounds the inner chamber, and a primary liquid stop structure that prevents immersion from the outside of the casing to the outer chamber, and from the outer chamber to the inner chamber A secondary liquid stop structure for preventing the immersion liquid, and a sensor for detecting the immersion liquid in the casing is provided in the outer chamber ,
The inner chamber is divided into a plurality of compartments, and a third liquid stop structure is provided to prevent liquid from entering and exiting between the compartments, and an electric cable is wired through a partition wall that separates the compartments. An actuator for driving a valve, characterized in that the time until the liquid is immersed is increased in order along the wiring direction of the electric cable . The motor is attached to a partition wall that partitions the inner chamber and the outer chamber, is disposed in the outer chamber, and is electrically connected to an electric cable wired in the inner chamber through the partition wall. The valve drive actuator according to claim 1 .

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