JP2539474B2 - Auto tensioner device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to the prevention of swaying of an undersea device which is suspended from a mother ship such as a deep-sea research boat, an undersea probe, or a capsule by a cable and stabilizes the cable tension. Regarding means.

(Prior art) When underwater equipment such as a deep-sea research boat, a submarine probe, or a capsule is suspended from the mother ship into the sea by a cable for ocean research or seafloor exploration, swaying of the mother ship due to sea level fluctuations occurs. In order to prevent transmission to undersea equipment via a cable and to keep the tension of the cable within a certain range, for example, a cable that connects the mother ship and the undersea equipment by installing sheaves at both ends of a ram cylinder hydraulically connected to an accumulator. There is known a passive type auto tensioner device in which is wound between the sheaves. When the cable tension increases, the ram cylinder contracts while accumulating pressure in the accumulator, and when the tension decreases, the ram cylinder expands due to the pressure accumulated in the accumulator. This allows the cable to be sent or taken in in response to a change in tension.

Further, the applicant of the present invention previously disclosed in Japanese Patent Application No. 62-258042,
In order to improve the vibration absorption efficiency, we have proposed an active and passive auto-tensioner system equipped with a seabo cylinder that detects the amount of vibration of the hull and actively expands and contracts the ram cylinder.

(Problems to be solved by the invention) By the way, when the underwater device is hung from a mother ship, immediately after landing on the water, or when the device is drained immediately after being raised from the sea to the surface of the sea, the device is submerged in the middle of the water due to sea level fluctuation. Since it is twisted or floats in the air, a snap load is applied to the cable, and the tension is likely to change drastically as shown by the broken line in FIG.

However, the above-mentioned auto tensioner device is intended to absorb the vibration and stabilize the tension when the undersea device is in the sea, and even if it tries to stabilize the tension by an active method against such a snap load. However, due to the reaction time from the detection of the fluctuation amount to the driving of the servo cylinder, it was difficult to compensate the tension in a timely manner.

The present invention has been made to solve the above problems,
An object of the present invention is to provide an auto tensioner device that can effectively absorb a snap load acting on a cable when landing or draining water.

(Means for Solving Problems) According to the present invention, a pair of sheaves wound around a midway of a cable for suspending an undersea device from a mother ship are elastically moved in a separating direction by accumulating pressure of a first accumulator hydraulically connected. An automatic tensioner device comprising: a ram cylinder that supports the ram cylinder; and a swing amount detection cylinder that elastically supports a cable between the ram cylinder and the subsea device by accumulating pressure of a second accumulator hydraulically connected to the ram cylinder. A flow control valve with a check valve and a switching valve for directly circulating the working oil without interposing the flow control valve are provided between the first accumulator and between the fluctuation detecting cylinder and the second accumulator. There is.

(Operation) When landing or draining water, set the average balance position of the ram cylinder near the most contracted position and the average balance position of the motion amount detection cylinder near the most expanded / contracted position, and the hydraulic oil flows through each flow rate adjusting valve. The switching valve is switched so that it does.

When the cable tension increases sharply, the sway amount detection cylinder contracts while allowing the hydraulic oil to flow into the second accumulator, but at that time, the flow rate adjustment valve resists the passage of this hydraulic oil and abruptly contracts the sway amount detection cylinder. resist. On the other hand, when the tension decreases, the hydraulic oil of the first accumulator flows into the ram cylinder without resistance through the check valve attached to the flow rate adjusting valve, and extends the ram cylinder to apply tension to the cable. This damps cable tension fluctuations caused by the snap load.

(Example) FIGS. 1 to 4 show an example of the present invention.

In FIG. 1, 1 is a cable, 2 is a motion amount detection cylinder, and 3 is a ram cylinder. A launcher 5 as an undersea device is supported at the tip of a cable 1 extending from the shaking amount detecting cylinder 2 to the left side in the figure through an arm 4 shown in FIG. 3, and a cable extending from the ram cylinder 3 to the right side in FIG. 1 is connected to a cable winch 7 via a traction winch 6 as shown in FIG.

Both the shaking detection cylinder 2 and the ram cylinder 3 are provided on the deck of the mother ship. The shake amount detection cylinder 2 is a sheave in which a cable 1 stretched between two sheaves 8 and 9 attached to a hull is attached to the tip of a piston rod 2A.
This is a single-acting hydraulic cylinder that elastically supports upwards via 10 and the cylinder portion 2B is the oil chamber of the second accumulator 11.
11A is communicated with a control valve 12 and a check valve-equipped flow rate adjusting valve 13 arranged in parallel therewith.

Inside the second accumulator 11 is an air chamber due to the piston 14.
11B is defined above the oil chamber 11A, and this air chamber 11B is connected to an air supply device (not shown). Control valve 12
Is an electromagnetic switching valve including a section 12A that allows the hydraulic oil to flow in a fully opened state and a section 12B that restricts the flow of the hydraulic oil by a fixed throttle.

The check valve-equipped flow rate adjusting valve 13 includes a variable throttle 13A and a check valve 13B which is arranged in parallel with the variable throttle 13A and which blocks outflow of hydraulic oil from the sway amount detection cylinder 2.

The ram cylinder 3 is also a single-acting hydraulic cylinder, and sheaves 15 and 16 are respectively supported by the base end of the cylinder portion 3B and the tip end of the piston rod 3A protruding from the cylinder portion 3B. 1 is laid over multiple articles. The cylinder portion 3B is provided with a first accumulator 19 via a control valve 17 and a flow control valve 18 with a check valve, which are constructed in the same manner as in the case of the fluctuation detecting cylinder 2.
Is connected to the oil chamber 19A. An air chamber 19B is defined in the first accumulator 19 above the oil chamber 19A via a piston 20, and the air chamber 19B is connected to an air supply device (not shown).

A servo cylinder 21 is interposed between the piston rod 3A and the cylinder portion 3B of the ram cylinder 3 as shown in FIG. The servo cylinder 21 is a double-acting cylinder in which the rod portion 21A is locked to the piston rod 3A and the cylinder portion 21B is locked to the cylinder portion 3B.
The sway of the mother ship is detected by a load cell and a stroke sensor (not shown) provided for the piston rod 3A, and the piston rod 3A is driven to the extension side or the contraction side in response to the hydraulic pressure control circuit and the pump (not shown). . As a result, the passive operation in which the ram cylinder 3 responds to the compressive force applied to the sheaves 15 and 16 and the active operation in which the servo cylinder 21 extends and retracts the ram cylinder 3 based on the amount of motion detected by the motion amount detection cylinder 2 are parallel. I am supposed to do it.

 Next, the operation will be described.

When the launcher 5 is in the air, the tension of the cable 1 is stable.
Is also in the most compressed position, that is, in the inoperative state. In addition, when the launcher 5 is submerged in the sea, the control valve 12 is used to absorb the wobbling of the ship and stabilize the cable tension by using the active operation and the passive operation described above together.
Switch to sections 12A and 17A respectively.

However, when the launcher 2 is landed or drained, the air chamber of the second accumulator 11 is operated by operating the air supply device.
Air is supplied to 11B to set the vibration detection cylinder 2 to the maximum extension state, while the air chamber 19B of the first accumulator 19 is set.
Then, the pressure is reduced to bring the ram cylinder 3 into a state close to maximum compression. Also, switch control valves 12 and 17 to sections 12B and 17B, respectively.

When landing or draining, for example, when the launcher 5 floats above the surface of the water and the tension of the cable 1 suddenly increases,
As shown in FIG. 1, the motion amount detecting cylinder 2 contracts from the most extended position. At this time, the fixed throttle 12B of the control valve 12 resists the hydraulic oil flowing from the cylinder portion 2B to the oil chamber 11A of the second accumulator 11. In addition, when the tension of the cable 1 starts to decrease, the contracted sway amount detection cylinder 2 expands again by the hydraulic oil in the oil chamber 11A of the second accumulator 11 flowing into the cylinder portion 2B from the check valve 13B without resistance. .

On the other hand, when the launcher 5 in the air lands on the water and the tension of the cable 1 decreases, the ram cylinder 3 in a state close to the most compressed state is expanded by the air pressure of the first accumulator 19 as shown in FIG. In this case, the hydraulic oil that flows into the ram cylinder 3 from the oil chamber 19A is the check valve 18 attached to the flow rate adjusting valve 18.
Pass B without resistance. Therefore, the ram cylinder 3 follows the cable 1 and expands smoothly, and the cable 1 always maintains a certain tension without causing slack. As a result, when the tension next increases, the cable 1 is sent out elastically and smoothly, and the occurrence of snap load is prevented in advance. In addition, when the tension of the ram cylinder 3 that has expanded changes to increase, the ram cylinder 3 contracts again while generating a certain resistance in the fixed diaphragm 18B.

In this way, the motion amount detection cylinder 2 is set to the maximum extension state,
By setting each of the ram cylinders 3 in a state close to the maximum compression, even if there is a sea level change that causes the tension of the cable 1 to suddenly change from the average to the decrease in the water landing or draining state, The tension of the cable 1 is immediately compensated. Further, since the flow rate adjusting valves 13 and 18 respectively provide appropriate resistance to the contraction of the motion amount detecting cylinder 2 and the ram cylinder 3, the tension fluctuation due to the snap load shown in the solid line in FIG. As shown in (3), the tension of the cable 1 is stabilized efficiently in a short time.

After the launcher 2 is completely submerged in the water from the landing state or is completely lifted in the air from the draining state, the control valves 12 and 17 are respectively set in the section 12
Switch to A and 17A and readjust the air pressure in the first and second accumulators 19 and 11 for the next stroke.

The control valves 12 and 17 are switched by visually checking the state of the launcher 2, or the traction winch 6 is equipped with a cable length meter (not shown) and based on the length of the cable 1 sent by the cable length meter. It is also possible to switch automatically.

(Effects of the Invention) As described above, in the autotensioner device of the present invention, the flow regulating valve with a check valve is interposed between the ram cylinder and the first accumulator and between the motion amount detection cylinder and the second accumulator, respectively. Since it is equipped with a switching valve that allows hydraulic oil to flow directly without going through this flow rate adjustment valve,
When landing or draining the water, set the average balance position of the ram cylinder near the most contracted position and the average balance position of the motion detection cylinder near the most extended position so that the hydraulic oil of both cylinders flows through the flow control valve. By switching the switching valve to, even if the cable tension suddenly increases or decreases, the expansion and contraction of these cylinders compensates the cable tension with good response. Further, at that time, since the flow rate adjusting valve gives resistance to these cylinder contractions, the fluctuation of the cable tension is efficiently attenuated, and the fluctuation of the tension is stabilized in a short time.

Therefore, the present invention has a great effect on the stability of the cable tension at the time of water landing and draining, which tends to cause tension fluctuation,
For example, it is possible to sufficiently satisfy the requirement for tension stability, which is indispensable when an optical fiber or the like is used as a pickup cable and also used as a signal transmission cable.

[Brief description of drawings]

1 and 2 are structural views of the essential parts of an automatic tensioner device showing an embodiment of the present invention, FIG. 3 is a layout diagram of the same automatic tensioner device, and FIG. 4 is a graph showing damping characteristics of tension fluctuations. Further, FIG. 5 is a graph for explaining a general change in tension applied to the cable. 1 ... Cable, 2 ... Motion detection cylinder, 3 ... Ram cylinder, 5 ... Launcher, 11 ... First accumulator, 12,17 ... Control valve, 13,18 ... Check valve with check valve Valve, 19 ... Second accumulator.

Claims (1)

(57) [Claims] 1. A ram cylinder for elastically supporting a pair of sheaves wound around a cable for suspending an undersea device from a mother ship in a separating direction by accumulating pressure of a hydraulically connected first accumulator, and the ram cylinder. In an autotensioner device including a swing amount detection cylinder elastically supporting a cable between a submarine device and a submerged device hydraulically by accumulating pressure of a second accumulator, a swing amount detection between the ram cylinder and the first accumulator and a swing amount detection. An autotensioner device comprising: a flow control valve with a check valve and a switching valve for directly circulating hydraulic oil, not through the flow control valve, between the cylinder and the second accumulator.