JP2539464B2 - Auto tensioner device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a shaking prevention means for an undersea device that is suspended from a mother ship such as a deep-sea research boat, a seabed probe, or a capsule by a cable and then works under the sea.

(Prior art) When an underwater device such as a deep-sea investigation boat, a sea-bottom explorer, or a capsule is hung from the mother ship to the sea with a cable for ocean surveys and sea-bottom exploration, the movement of the mother ship due to sea level fluctuations may occur. Cable tension must be kept within a certain range to prevent transmission to underwater equipment via the cable.

As a mechanism for this, for example, a passive type auto tensioner device in which sheaves are attached to both ends of a ram cylinder connected to an accumulator and a cable connecting a mother ship and an underwater device is wrapped around the sheave over a plurality of lines is known. Have been. In this case, the ram cylinder contracts while accumulating pressure in the accumulator when the cable tension increases, and expands due to the pressure accumulated in the accumulator when the tension decreases. This allows the cable to be sent or taken in in response to a change in tension.

(Problems to be Solved by the Invention) However, in the case of this device, the ram cylinder does not expand or contract unless the cable tension fluctuates more than a certain value due to frictional resistance of the sheave and internal friction of the ram cylinder and the accumulator. It is easy to transmit to the underwater equipment without absorbing small sway. That is, there is a dead zone for tension change near the neutral position of the ram cylinder, which causes a problem that the damping rate of tension fluctuation is low.

On the other hand, recently, the use of optical fiber for such a cable for retrieval has often led to the dual use of the signal transmission cable between the mother ship and the undersea equipment, in which case the malfunction of the signal circuit due to the deformation or damage of the cable is prevented. In order to achieve this, it is particularly necessary to keep the cable tension constant.

The present invention has been made in view of the above problems, and by positively controlling the expansion and contraction of the ram cylinder by detecting the motion of the hull, further stabilizing the undersea device while preventing fluctuations in the cable tension. The purpose is to plan.

(Means for Solving the Problems) The present invention uses the accumulator hydraulically connected to store the midway of a cable for suspending an undersea device from a mother ship by winding it between sheaves of a ram cylinder provided on the mother ship. In an auto tensioner device that elastically supports a ram cylinder in the extension direction, the ram cylinder is configured by a double-acting hydraulic cylinder, and the ram cylinder is selectively connected to the accumulator and a hydraulic supply device via a servo valve. And a hydraulic control circuit for driving and controlling the ram cylinder via a servo valve so as to absorb the detected shaking.

(Operation) When the accumulator is hydraulically connected to the ram cylinder, passive operation is performed by the pressure accumulation operation of the accumulator. On the other hand, when the switching valve is switched to the servo valve side, the hydraulic control circuit supplies the hydraulic pressure to the ram cylinder via the servo valve according to the amount of shaking of the mother ship detected by the detecting means to absorb the shaking. Control the ram cylinder in the direction. Due to this active operation, the ram cylinder operates in response to changes in cable tension, even in small movements that cannot be activated due to frictional resistance in the passive movement. Absorbs at a high attenuation rate.

(Embodiment) FIGS. 1 to 3 show an embodiment of the present invention.

In FIG. 1, reference numeral 1 is a mother ship, 2 is a launcher as an undersea device, and an A-shaped frame 3 projecting to the rear of the stern of the mother ship 1.
It is hung from the sheave 3A attached to the tip of the cable by the cable 4 into the sea.

The mother ship 1 is provided with a cable winch 5 and a traction winch 6 on a deck 9 for winding and sending out the cable 4. In the middle of the cable 4, a rocking amount detecting cylinder 7 as a rocking amount detecting means of the mother ship 1 is provided.
And a ram cylinder 8 for absorbing shaking are interposed in series.

The shaking amount detection cylinder 7 is a single-acting hydraulic cylinder in which a cylinder portion 7A is fixedly mounted on a deck 9, and a sheave 10 is supported at the tip of a piston rod 7B protruding upward from the cylinder portion 7A, and the deck 9 on both sides thereof is supported. Sheaves 11 and 12 are attached to. The cable 4 is wound around the lower sides of the sheaves 11 and 12 and the upper side of the sheave 10, and the sheave 10 is urged downward by the tension of the cable 4. A stroke sensor for detecting the amount of displacement of the sheave 10 is provided in the wobbling amount detection cylinder 7.
20 is attached, and a load cell 21 for detecting a load is installed in the piston rod 7B. The cylinder portion 7A of the motion amount detecting cylinder 7 is connected to the accumulator 13 as shown in FIG.

The accumulator 13 is filled with compressed nitrogen for pressurizing the hydraulic oil flowing between it and the cylinder portion 7A. Further, the accumulator 13 is connected to a power unit 31, which is a hydraulic pressure supply device, via a solenoid valve 30. The power unit 31 is composed of a hydraulic pump 31A for supplying hydraulic oil under pressure and a tank 31B for collecting the hydraulic oil. Further, in order to set the pressure of the accumulator 13, an electromagnetic proportional relief valve 33 that returns hydraulic oil to the tank 31B under the control of the controller 22 described later is provided in parallel with the electromagnetic valve 30. Reference numeral 32 is a pressure detector that detects the hydraulic pressure of the accumulator 13 and the vibration amount detection cylinder 7.

The ram cylinder 8 is a double-acting hydraulic cylinder, and sheaves 14 and 15 are respectively supported by the base end of the cylinder portion 8A and the tip end of the piston rod 8B protruding from the cylinder portion 8A. 4 is laid over multiple lines. A stroke sensor indicating the stroke position of the ram cylinder 8 is provided between the cylinder portion 8A and the piston rod 8B.
23 are intervened.

The inside of the cylinder portion 8A is divided into an upper oil chamber 34 and a lower oil chamber 35. The ram cylinder 8 is connected to the accumulator 16 via the switching valve 36, so that the ram cylinder 8 is passively driven by the change in tension of the cable 4 as in the conventional example, and is controlled by the controller 22 as a hydraulic control circuit. Pressure oil is selectively supplied from the power unit 31 via the servo valve 18 to perform active operation as a servo cylinder.

The switching valve 36 is hydraulically switched, so that the hydraulic pressure of the power unit 31 is transferred via the solenoid valve 37 to the switching valve 36.
Is supplied to. Further, the oil chamber 16A of the accumulator 16 is provided with a power unit via a solenoid valve 38 for replenishing hydraulic oil.
Connected to 31. On the other hand, the air chamber 16 of the accumulator 16
B is connected to the air bottle 41 and the compressor unit 42. A pressure control valve (not shown) controlled by the controller 22 is provided on the pipe connecting the air chamber 16B and the air bottle 41.

Reference numerals 39 and 40 are solenoid valves provided between the power unit 31 and the power unit 31 for driving the cable winch 5 and the traction winch 6, respectively. Further, the traction winch 6 has a cable length meter 24 for detecting the length of the cable 41 sent out.
In addition, an interlock mechanism (not shown) is provided between the servo valve 18 and the solenoid valve 40 so that the ram cylinder 8 cannot be actively driven while the traction winch 6 is operating.

The controller 22 includes the stroke sensors 20 and 23,
The load cell 21, the cord length meter 24, and the pressure detector 32 are connected by a signal circuit, respectively, and their detected values are input as a signal current.

The switching valve 36 of the controller 22 is the accumulator 16
In the passive operating state of the ram cylinder 8 which communicates with the ram cylinder 8, the weight of the cable 4 sent out is calculated based on the input signals from the stroke sensors 20 and 23 and the line length meter 24, and this weight is calculated. In order to keep the average balance position of the ram cylinder 8 in the middle between the most compressed position and the most extended position against changes, the accumulator 16 and the air bottle
Air chamber 16B via a pressure control valve installed between 41 and
Control the pressure of. The stroke position signal input from the stroke sensor 23 is fed back to the control of this pressure control valve.

Further, in the active operating state of the ram cylinder 8 in which the switching valve 36 is switched to the shut-off position, hydraulic oil is supplied to the swaying force detection cylinder 7 and the accumulator 13 via the solenoid valve 30, and then the rope length meter 24 and stroke Sensor 20
Also, the pressure of the cable 4 applied to the motion amount detection cylinder 7 is calculated based on the signal input from the load cell 21, and the electromagnetic proportional relief valve 33 is opened to set the motion amount detection cylinder 7 at the intermediate position between the maximum compression and the maximum expansion. A part of the hydraulic oil supplied until the balance is returned to the tank 31B. The hydraulic oil pressure signal-input from the pressure detector 32 to the controller 22 is fed back to the control of the solenoid proportional valve 33.

After this setting, the controller 22 switches the servo cylinder 18 and controls the flow rate based on the motion amount of the mother ship 1 detected and input by the stroke sensor 23 as a stroke position signal, and drives the ram cylinder 8 in a direction to absorb the motion. To do.

 Next, the operation will be described.

When the launcher 2 is suspended from the A type frame 3 to the surface of the sea, the solenoid valve 30 is switched to the section on the right side shown in FIG. 2 and the hydraulic oil of the motion amount detection cylinder 7 and the accumulator 13 is returned to the tank 31B in advance to cause the motion. The quantity detection cylinder 7 is kept in the most compressed state. Further, as shown in FIG. 2, the servo valve 18 is held in the shut-off position, the switching valve 36 is held in the communicating position via the solenoid valve 37, and the solenoid valve 38 is switched to the section on the right side of the drawing, thereby the ram cylinder. 8 and the hydraulic oil of the accumulator 16 are returned to the tank 31, and the ram cylinder 8 is also in the most contracted state. In this state, the cable winch 5 and the traction winch 6 are extended to suspend the launcher 2.
While the vehicle is in the air, the tension of the cable 4 is hardly affected even if the mother ship 1 sways.

Immediately after the launcher 2 reaches the water, the solenoid valve 38 is switched to operate the oil chamber 34 of the ram cylinder 8 and the oil chamber of the accumulator 16.
The hydraulic oil is supplied to the 16A from the power unit 31, and the ram cylinder 8 is resisted against the tension of the cable 4 supporting the launcher 2.
Is stretched to an intermediate position between maximum compression and maximum extension. After this,
Cable winch 5 and traction winch 6
To extend the launcher 2 to a predetermined water depth.

In this process, when the mother ship 1 rocks, the ram cylinder 8 expands and contracts according to the spring characteristic of the compressed air due to the direct action of the tension change of the cable 4. That is, the vibration of the mother ship 1 is absorbed by performing the passive motion of the vibration as in the conventional example.

During this time, the controller 22 calculates the weight of the cable 4 delivered by the above-described method and controls the pressure control valve corresponding to this, and supplies the compressed air of the air bottle 41 to the air chamber 16B of the accumulator 16 little by little. Thus, the repulsive force of the ram cylinder 8 is strengthened to prevent the average balance position from changing. Therefore, the average balance position of the ram cylinder 8 is kept constant regardless of the length of the cable 4, and even when the launcher 2 is suspended in the deep sea by using the long cable 4, the vibration absorbing ability of the ram cylinder 8 is affected. There is no such thing.

Further, since the switching of the servo cylinder 18 is restricted by the interlock mechanism during the operation of the traction winch 6, the ram cylinder 8 does not perform active operation only by passive operation. In other words, the pressure oil of the power unit 31 is used only for driving the traction winch 6,
There is no risk of the power unit 31 overloading.

Now, when the launcher 2 descends to the specified position, the solenoid valve
Switch between 39 and 40 to stop the operation of the cable winch 5 and traction winch 6. Then, the average balance position of the motion amount detection cylinder 7 is set by the above method. This setting may be automatically performed by the controller 22 or manually by an operator.

Next, the switching valve 36 is switched to the shutoff position via the solenoid valve 37. As a result, communication between the oil chamber 34 and the accumulator 16, and between the oil chamber 35 and the tank 31B is cut off. After that,
The controller 22 receives the signal from the stroke sensor 20 and determines the stroke position of the motion amount detection cylinder 7 by the stroke position of the mother ship 1.
The amount of fluctuation of the servo valve is detected and the servo valve is designed to absorb this fluctuation.
The ram cylinder 8 is expanded and contracted as a servo cylinder by opening / closing 18 and adjusting the opening.

That is, for example, when the mother ship 1 is lifted along with the fluctuating sea surface, the tension of the cable 4 increases, and the motion amount detection cylinder 7 is compressed while accumulating in the accumulator 13. The controller 22 that has detected the compression displacement of the shaking amount detection cylinder 7 from the input signal of the stroke sensor 20 uses the oil chamber 35 of the ram cylinder 8 as the pump 31A and the oil chamber 34 as the tank 31B.
The ram cylinder 8 is driven toward the compression side by controlling the flow rate according to the displacement speed. As a result, the cable 4 wound around the sheaves 14 and 15 at both ends of the ram cylinder 8
Is sent into the sea and holds the launcher 2 at a fixed position with respect to the mother ship 1 lifted along with the sea surface,
The increase in tension applied to the cable 4 is prevented.

In addition, when the mother ship 1 descends due to sea level changes, the cable 4
Becomes loose, and the vibration amount detection cylinder 7 expands due to the pressure stored in the accumulator 13. The controller 22 that has detected this displacement from the input signal of the stroke sensor 20 immediately switches the servo valve 18 and the oil chamber 34 to the pump 31A.
The oil chamber 35 is connected to the tank 31B, the flow rate is controlled according to the displacement speed of the motion amount detection cylinder 7, and the ram cylinder 8 is extendedly driven. As a result, the distance between the sheaves 14 and 15 is increased, and the cable 4 is taken into the ship from the sea. Therefore, the launcher 2 is still held at a fixed position in the sea with respect to the mother ship 1 that descends along with the sea surface, and the tension of the cable 4 is maintained without decreasing.

In this case, since the ram cylinder 8 is forcibly driven as a servo cylinder based on the displacement of the sway amount detection cylinder 7, the ram cylinder 8 is against a small sway that does not operate due to frictional resistance in passive operation. Also operates smoothly and responds faithfully to the shaking of the mother ship 1 with good response. Therefore, the dead zone near the neutral position due to frictional resistance is eliminated, and the vibration is absorbed at a high damping rate.

Since such shaking of the hull is often regulated, a specific waveform pattern is preset in the controller 22, or a waveform pattern read from the output signal of the position sensor 20 is automatically set in the controller 22. In this way, it is possible to control the servo valve 18 based on this waveform pattern.

On the other hand, when the launcher 2 is lifted from the sea surface to the sea surface, the motion amount detection cylinder 7 is set to the most compressed state in the same manner as when the launcher 2 is suspended from the sea surface to absorb the motion of the mother ship 1 by the passive operation of the ram cylinder 8, and When the ram cylinder 8 is recovered from the mother ship 1, the ram cylinder 8 is set to the most compressed state as in the case where the ram cylinder 8 is suspended from the mother ship 1 to the sea surface.

In this embodiment, as a means for detecting the shaking amount of the mother ship, the shaking amount detecting cylinder 7 having a stroke sensor 20 is used.
However, instead of the stroke sensor 20, a sheave
A rotary encoder 50 as shown in FIG. 3 may be provided in each of 11 and 12, and the sway of the mother ship 1 may be detected from the detected difference in rotational speed between the sheaves 11 and 12. In this case, the controller 22 controls the servo valve 18 in the direction to eliminate the difference in the rotational speeds of the sheaves 11 and 12.

Further, in this embodiment, the swing of the mother ship 1 during the lifting or lowering operation of the launcher 2 in the sea is absorbed only by the passive operation.
Also, the power unit 31 has a capacity sufficient to drive the traction winch 6 and the ram cylinder 8 at the same time.
It is also possible to make the ram cylinder 8 always perform active operation for the underwater launcher 2.

(Effects of the Invention) As described above, in the auto tensioner device of the present invention, the ram cylinder that compensates the cable tension by expansion and contraction is connected to the hydraulic pressure supply device via the servo valve in accordance with the switching operation of the switching valve, and the detection means is The hydraulic control circuit controls the drive of the ram cylinder via the servo valve so as to absorb the detected shaking of the mother ship, which enables active operation of the ram cylinder. This active operation can absorb small fluctuations that cannot be absorbed by passive operation due to the friction resistance of the ram cylinder, and also improve the responsiveness of the ram cylinder to the fluctuations of the hull, and absorb the fluctuations with a high damping rate. You can

Therefore, a cable that stabilizes the posture of the device and suspends it by arbitrarily selecting active operation having such advantages and passive operation that does not require a driving force in accordance with the suspended state of the undersea device. The ability to prevent sudden tension fluctuations in is significantly improved. In addition, the improvement in this capability can sufficiently satisfy the requirement when the pickup cable is also used as a signal transmission cable by using an optical fiber or the like.

[Brief description of drawings]

FIG. 1 is a shipboard layout of an autotensioner device showing an embodiment of the present invention, FIG. 2 is a circuit diagram of the same, and FIG. 3 is a side view of a rotary encoder showing another embodiment of the motion amount detecting means. 1 ... Mother ship, 2 ... Launcher, 4 ... Cable, 7 ...
Shake amount detection cylinder, 8 …… Ram cylinder, 14, 15 ……
Sheave, 16 ... Accumulator, 18 ... Servo valve, 20 ... Stroke sensor, 22 ... Controller, 31
...... Power unit, 36 …… Switching valve.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-86390 (JP, A) JP-A-61-86392 (JP, A)

Claims (1)

(57) [Claims] 1. A cable for suspending an undersea device from a mother ship is wound around a sheave of a ram cylinder provided on the mother ship, and the ram cylinder is elastically supported in an extending direction by accumulator pressure hydraulically connected. In the auto tensioner device, the ram cylinder is composed of a double-acting hydraulic cylinder, and a switching valve for selectively switching and connecting the ram cylinder to the accumulator and the hydraulic pressure supply device via a servo valve is provided, and the An autotensioner device comprising: a means for detecting a shaking amount; and a hydraulic control circuit for driving and controlling a ram cylinder via a servo valve so as to absorb the detected shaking.