JPS6348632Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is a variable capacity tensioner, and more specifically, a tensioner that absorbs shock when the load suddenly changes, such as when lifting and lowering diving equipment on a ship. Regarding variable capacity tensioners used to protect etc.

BACKGROUND ART AND PROBLEMS The tensioner shown in FIG. 1 is conventionally known as this type of tensioner. This tensioner consists of an oil tank 1, a hydraulic cylinder 2, an accumulator 3 in which oil and gas are sealed, an oil supply pipe 4 connecting the oil tank 1 and the accumulator 3, and a pump installed on the oil tank 1 side of the oil supply pipe 4. 5. A valve 6 provided on the oil supply pipe 4 on the side of the accumulator 3, and an oil chamber 7 of the hydraulic cylinder 2 and the accumulator 3.
It is composed of an oil communication pipe 8 that connects the oil side of the
The hydraulic cylinder 2 is incorporated into a ship's cargo handling equipment, etc.
A cable 11 is hung around a pulley 10 attached to the tip of the piston rod 9. During normal use, the valve 6 is closed, and when the load acting on the cable 11, ie, the piston rod 9, changes suddenly, the impact is absorbed by the compressibility of the gas sealed in the accumulator 3.

However, in the case of this tensioner, once the gas is filled in the accumulator 3, its compressibility becomes constant, so the operating range of the tensioner is fixed. This is fine as long as the load acting on the tensioner is within a certain range, but if the load increases or decreases to a certain extent, it will no longer be able to function as a tensioner. For this reason, there is a desire for a variable capacity tensioner whose operating range can be changed in response to changes in load.

In order to change the operating range of the tensioner in response to changes in load, it is sufficient to change the gas pressure in the accumulator 3 in response to changes in load. The gas pressure is changed by discharging gas, but since this gas pressure is always fluctuating due to fluctuations in the piston rod 9, when adjusting the gas pressure by injecting and discharging gas, it is necessary to It is difficult to determine the target pressure value, and therefore it is difficult to adjust the gas pressure, that is, the operating range.

The purpose of this invention is to solve the above problems and provide a variable capacity tensioner whose operating range can be easily changed in response to changes in load.

Means to Solve the Problems The variable capacity tensioner of this invention consists of a hydraulic cylinder, three accumulators in which oil and gas are sealed, an oil level gauge installed in each of the three accumulators, and an oil chamber of the hydraulic cylinder. An oil communication passage connecting the oil side of the first accumulator, a gas communication passage connecting the gas sides of the three accumulators, a valve provided in the gas communication passage on the third accumulator side, and a valve provided in the gas communication passage between the second accumulator and the third accumulator. This system is equipped with an oil supply and discharge device that can individually supply and discharge oil to the three accumulators.

Function and effect of the invention During normal use, the valve of the gas communication passage on the third accumulator side is closed, and the oil supply and discharge device is in a state where it can supply and discharge oil to and from the second accumulator, and the tensioner is When the applied load suddenly changes, the shock is absorbed by the compressibility of the gas sealed in the first and second accumulators and the gas communication passage. Then, in response to changes in load, the oil amount in the second accumulator is adjusted by supplying oil to and draining oil from the second accumulator using an oil supply/drainage device. The gas pressure of the first and second accumulators, that is, the operating range of the tensioner can be easily changed. That is, as will be described later, when the oil amount in the hydraulic cylinder and the first accumulator and the gas amount in the first and second accumulators are constant, the relationship between this gas pressure and the oil amount in the second accumulator is constant. There is a certain relationship between them. In addition, the oil level in the second accumulator is indicated by the oil level gauge, and the oil level gauge's indication does not change even if the gas pressure fluctuates, so the oil level gauge's indication corresponds to the required load. The gas pressure, that is, the tensioner's operating range can be changed in response to changes in load by a simple operation of adjusting the amount of oil in the second accumulator using the oil supply/drainage device to achieve the desired value.

On the other hand, when the initial load acting on the tensioner changes, the valve of the gas communication passage on the third accumulator side is opened and the oil supply/drainage device is placed in a state where oil can be supplied/discharged to/from the third accumulator. By adjusting the amount of oil in the third accumulator by supplying oil to and discharging oil from the third accumulator using a supply/discharge device, it is possible to adjust the amount of oil in the third accumulator without supplying or discharging oil to the second accumulator. , the gas pressure of the first and second accumulators, that is, the operating range of the tensioner, can be easily changed. At this time as well, the oil level in the third accumulator is indicated by the oil level gauge, and even if the gas pressure fluctuates, the oil level gauge's indication does not change, so the oil level gauge's indication does not match the required load. The gas pressure, that is, the tensioner's operating range, can be changed in response to changes in the initial load by simply adjusting the amount of oil in the third accumulator using the oil supply/drainage device to the corresponding value. can.

As described above, according to the variable capacity tensioner of this invention, the operating range can be easily changed in response to changes in load.

Embodiment Hereinafter, an embodiment of this invention will be described with reference to FIGS. 2 to 4.

In FIG. 2, the variable capacity tensioner includes a hydraulic cylinder 20, three accumulators 21, 22, 22' in which oil and gas are sealed, and oil level gauges provided in each of the three accumulators 21, 22, 22'. 26a, 26b, 26c, hydraulic cylinder 2
An oil communication pipe (oil communication passage) 24 connects the oil chamber 23 of No. 0 and the oil side of the first accumulator 21; ) 25, 25', 2nd
and a gas communication pipe 2 on the third accumulator 22' side that connects the third accumulators 22, 22'.
5', and an oil supply/discharge device 27 that can individually supply and discharge oil to and from the second and third accumulators 22 and 22'.

The oil supply and discharge device 27 includes an oil tank 28 and an oil tank 2.
8 and the second accumulator 22, an oil supply pipe 29 connecting the oil tank 28 and the third accumulator 2
2', oil supply pipe 29', oil supply pipe 29, 2
A pump 30 provided on the oil tank 28 side of 9′,
Accumulators 22, 2 of oil supply pipes 29, 29'
valves 31, 31' provided on the 2' side, an oil discharge pipe 32 connecting the oil supply pipes 29, 29' to the accumulators 22, 22' and the oil tank 28, and an oil discharge pipe 3.
It consists of a valve 33 provided at 2. Furthermore, an oil supply pipe 35 including a valve 34 is provided between the pump 30 and the first accumulator 21 . The pump 30 is preferably of a constant displacement type, and must have a horsepower sufficient to withstand pressure fluctuations.

The above-mentioned tensioner is incorporated into a device for raising and lowering diving equipment on a ship, and a cable 37 is attached to a pulley 37 attached to the tip of a piston rod 36 of a hydraulic cylinder 20.
Multiplyed by 8. During normal use, valves 31', 33, 34, and 39 are closed;
is open. cable 38 or piston rod 3
When the load acting on the gas cylinder 6 suddenly changes, the impact is absorbed by the compressibility of the gas sealed within the first and second accumulators 21 and 22 and the gas communication pipe 25. By adjusting the gas pressures of the first and second accumulators 21 and 22, the operating range of the tensioner can be changed in response to changes in load. This is done by adjusting the amount of oil in the second accumulator 22 with the drain device 27. In addition to the above, the third accumulator 22' is connected to the first and second accumulators 22' in order to be able to accommodate changes in the initial tension acting on the cable 38.
It adjusts the initial gas pressure of 1 and 22,
The valve 31 of the oil supply/drainage device 27 is closed, the valve 31' is opened, and the second and third accumulators 22,
Open the valve 39 of the gas communication pipe 25' of 22' to supply oil to the third accumulator 22' to increase the gas pressure of the first and second accumulators 21 and 22, or open the valve 33 to supply oil to the tank 28. It has a function of lowering the gas pressure of the first and second accumulators 21 and 22 by returning the oil of the third accumulator 22' to the third accumulator 22'. Line A in Figure 3,
As shown by A', there is a certain relationship between the gas pressure and the load of the first and second accumulators 21 and 22 when the tensioner is in the neutral position, and once this gas pressure is determined, , upper limits C, C' and lower limits D, D' of the tensioner operating ranges B, B' are determined. Note that A', B', C', and D' indicate an example in which the initial gas pressure is changed by the third accumulator 22'. Therefore, by changing the gas pressure, the operating range of the tensioner can be changed arbitrarily.
Furthermore, as shown by the solid line E and the broken line E' in FIG. In this case, there is a certain relationship between the gas pressure and the amount of oil in the second accumulator 22. Furthermore, the initial gas pressure can be arbitrarily selected by supplying and discharging oil to the third accumulator 22'. In this way, the initial gas pressure can be set arbitrarily, and the second
When the amount of oil in the accumulator 22 is determined, the gas pressure is determined, and furthermore, the operating range of the tensioner is determined as described above. Therefore, by operating the pump 30 and valves 31, 33 of the oil supply/discharge device 27 to change the amount of oil in the second accumulator 22, the operating range of the tensioner can be changed as desired.
At this time, the oil level in the second accumulator 22 is indicated by the oil level gauge 26b, so the oil level gauge 26b
The amount of oil in the second accumulator 22 may be adjusted so that the instruction 6b becomes a value corresponding to the required load. Further, even if the gas pressure changes due to changes in the piston rod 36 of the hydraulic cylinder 20, the indication on the oil level gauge 26b does not change, making it easy to adjust the oil amount. Further, if the oil level gauge 26b is provided with a scale corresponding to the load, the oil amount can be adjusted even more easily.

[Brief explanation of the drawing]

Figure 1 is a pipe system diagram showing a conventional example, Figures 2 to 4
The figure shows an example of this invention, Figure 2 is a pipe system diagram, Figure 3 is a graph showing the relationship between gas pressure and load,
FIG. 4 is a graph showing the relationship between gas pressure and oil amount in the second accumulator. 20... Hydraulic cylinder, 21... First accumulator, 22... Second accumulator, 2
2'...Third accumulator, 23...Oil chamber,
24...Oil communication pipe (oil communication passage), 25, 25'...
Gas communication pipe (gas communication path), 26a, 26b, 2
6c...Oil level gauge, 27...Oil supply/drainage device, 39...
valve.

Claims (1)

[Scope of utility model registration request] Hydraulic cylinder 20, three accumulators 21, 22, 22' in which oil and gas are sealed, oil level gauges 26a, 26b, 26c provided in three accumulators 21, 22, 22', respectively, and hydraulic cylinder 20. Oil chamber 23 and first accumulator 21
an oil communication passage 24 that connects the oil side of the third accumulator 2; a gas communication passage 25, 25' that connects the gas sides of the three accumulators 21, 22, 22';
A variable valve equipped with a valve 39 provided in the gas communication passage 25' on the 2' side, and an oil supply/discharge device 27 that can individually supply and discharge oil to the second and third accumulators 22 and 22'. Capacity tensioner.