JP4884752B2 - Deck crane hydraulic drive - Google Patents

Description

  The present invention is used in a deck crane that is installed in a ship and that loads or unloads a load on a ship by a hoisting device that is directly connected to a hydraulic motor and is connected to a hydraulic motor from a hydraulic pump. Is provided with a control valve for switching the hoisting, neutral and unwinding operations of the hoisting device, and is connected to the hydraulic oil outlet hydraulic oil passage and opens and closes the hydraulic oil passage between the hydraulic motor outlet and the control valve. The present invention relates to a hydraulic drive device for a deck crane having a balance valve.

As shown in FIG. 5, a deck crane that is installed in a ship and loads or unloads a load on the ship by a hoisting device that is directly connected to the hydraulic motor is provided with two directly connected tandem hydraulic motors 21, A hoisting device 1 that is directly connected to 22 is equipped with a hydraulic drive device that loads or unloads a load on a ship.
In this hydraulic drive device, 9 is a hydraulic pump, and the hydraulic oil from the oil tank 10 is sent to the hydraulic motors 21 and 22 through the control valve 7 and the hydraulic oil passage 12 to drive the hydraulic motors 21 and 22. The hoisting device 1 is wound up, neutralized and unwound and driven.

The control valve 7 is normally constituted by a manual three-way switching valve, and the supply of the hydraulic oil to the hydraulic oil passage 12 connected to the hydraulic motors 21 and 22 is switched to cut off the hoisting device. The operation of 1 winding, neutral and unwinding is switched.
Reference numerals 3 and 3 are counter balance valves provided corresponding to the hydraulic motors 21 and 22, respectively. The counter balance valves 3 and 3 squeeze the hydraulic oil in the hydraulic oil passage 12 with the variable throttles 6 and 6 so that the flow rate and pressure are reduced. The hydraulic oil passage 11 or the hydraulic oil passage 14b connecting the hydraulic motors 21 and 22 and the control valve 7 is opened and closed by the pilot hydraulic pressure with reduced pressure, and the hoisting device 1 is wound up, neutralized and unwound. The working hydraulic pressure at the time is kept at the required hydraulic pressure. 13 and 14 are hydraulic oil passages at the outlets of the hydraulic motors 21 and 22, respectively, 33 and 330 are check valves, 4 is a sequence valve, and 8 is a hydraulic oil pressure adjustment valve.

In such a hydraulic drive device, when the control valve 7 is set to the hoisting position of the hoisting device 1, the hydraulic oil branched from the hydraulic oil passage 12 is throttled by the variable throttle 6 as shown in FIG. 3 and 3, the counter balance valves 3 and 3 are opened, and the hydraulic motors 21 and 22 side and the control valve 7 side are communicated to enable the winding operation.
When the control valve 7 is switched to neutral after setting the load to the hoisting position, the pilot hydraulic pressure is shut off and the counter balance valves 3 and 3 are closed, whereby the hydraulic pressure on the hydraulic motors 21 and 22 side is maintained at a constant hydraulic pressure. The load suspended by the hoisting device 1 is held at a certain height position.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 9-249387) discloses a hydraulic drive device for a deck crane that is installed in a ship and loads or unloads a load on the ship by a hoisting device that is directly connected to a hydraulic motor. However, a hydraulic drive device is disclosed that can hold the load stably and quickly after the suspension line is connected to the load.

Japanese Patent Laid-Open No. 9-249387

  In a deck crane hydraulic drive apparatus having a counterbalance valve 3 as shown in FIG. 5, after the hoisting apparatus 1 lifts the load by the hydraulic motors 21 and 22, the load is lowered when the load is lowered. As the hoisting device 1 rotates in the reverse direction due to its own weight and the hydraulic motors 21 and 22 perform a pumping action, a negative pressure is generated in the hydraulic oil supply path to the hydraulic motors 21 and 22. , 22 sucks air, the operation becomes unstable, and the hoisting device is idly rotated, and the idling of the hoisting device causes a sudden drop of the load, which hinders safe cargo handling work by the deck crane.

Further, in this prior art, when the hoisting device 1 hoists the load by the hydraulic motors 21 and 22, the hydraulic motors 21 and 22 are switched when the control valve 7 is switched to neutral to stop the load at the hoisting position. The peak hydraulic pressure due to the hydraulic pulsation is generated on the outlet side, and the hydraulic pressure leaks and breaks the hydraulic oil system easily due to the peak hydraulic pressure, so that safe cargo handling work is likely to be hindered.
There are problems to be solved.

  In view of the problems of the prior art, the present invention prevents the load of the deck crane from falling and avoids the occurrence of negative pressure in the hydraulic oil supply path to the hydraulic motor when unloading the deck crane. It is an object of the present invention to provide a hydraulic drive device that can reduce a peak hydraulic pressure caused by hydraulic pulsation when a load is stopped at a hoisting position by a control valve after hoisting the hoist and can realize a safe cargo handling operation.

The present invention achieves this object, and is a hydraulic drive device for a deck crane that is installed in a ship and loads or unloads a load on the ship by a hoisting device that is directly connected to a hydraulic motor. A control valve for switching the hoisting, neutral, and unwinding operations of the hoisting device is provided in the hydraulic oil supply path connected to the hydraulic motor from the hydraulic motor, and connected to the hydraulic oil outlet at the hydraulic motor outlet by pilot hydraulic pressure. In a deck crane hydraulic drive apparatus having a counterbalance valve for opening and closing a hydraulic oil passage between the hydraulic motor outlet and the control valve, a tandem hydraulic motor in which two of the hydraulic motors are connected in series is configured. Two counter balance valves are provided corresponding to the tandem hydraulic motor, and an accumulator is provided. And each said two counterbalance valve of the tandem type hydraulic motor respectively provided on two of the hydraulic oil path connecting respectively, to the outlet side of the individual hydraulic motors of the two working oil passages, the accumulator Respectively,
When the hoisting device hoists the load by the hydraulic motor, the two hydraulic oil passages are switched to the neutral position by switching the control valve to neutral and stopping the load at the hoisting position. Configured to generate a peak hydraulic pressure due to hydraulic pulsation on the outlet side of the
The accumulator provided separately to the two working oil passage said, the energy of the outlet side of the pressure variation of the hydraulic motor at the time of stop of the hoisting device, once accumulated in the accumulator winding energy during winding of the next It is configured to be used.

According to this invention, in the case of a tandem hydraulic motor in which two hydraulic motors are connected in series, preferably a hydraulic oil passage between the hydraulic oil outlet of the hydraulic motor that drives the hoisting device and the counterbalance valve, the tandem since the accumulator to the hydraulic fluid path between the individual and the two counterbalance valve type hydraulic motor is provided respectively, after the hoisting gear has hoisting the cargo by a hydraulic motor, by switching the control valve to a neutral load when stopping the winding position, a peak oil pressure on the outlet side of the hydraulic motor that to be generated by the accumulator absorbs hydraulic pulsation, at the outlet side of the hydraulic motor at the time of winding the stop position of the load Generation of peak oil pressure can be avoided. As a result, it is possible to prevent hydraulic oil leakage and breakage of the hydraulic oil system and to maintain safe cargo handling work.
Further, the energy of the outlet side of the pressure variation of the hydraulic motor during downward movement of the stop and the load of the hoisting apparatus, such as, can be used to accumulate one Dana accumulator to winding energy during winding of the next Thus, the energy efficiency of the cargo handling work is improved.

In this invention, the control port of the control valve is set to be closed at a neutral position, and the individual hydraulic fluid passages between the counter balance valve and the control valve are provided in the individual hydraulic fluid passages. preferably provided husband of the hydraulic motor outlet people provided with accumulator and different, of the accumulator.
With this configuration, after the hoisting device has lifted the load by the hydraulic motor, when the control valve is switched to neutral, the control port of the control valve is set to be closed. Even when leakage of hydraulic oil occurs, the control port of the control valve is closed, so that it is possible to prevent the load from dropping from the load lifting stop position, and the hydraulic oil between the counterbalance valve and the control valve. the road, by providing respectively provided with accumulator and different, of the accumulator to the individual hydraulic motors outlet of the two working oil passages, the working oil passage leading to the control port of said hydraulic fluid passages clogging control valve Pressure fluctuations associated with the switching of the control valve can be reduced.

According to the present invention, since the accumulator is provided respectively to the hydraulic fluid path between the hydraulic fluid outlet and the counterbalance valve of the hydraulic motor for driving the hoisting device, the outlet side of the hydraulic motor in winding stop position of the load It is possible to avoid the occurrence of peak oil pressure at. As a result, it is possible to prevent hydraulic oil leakage and breakage of the hydraulic oil system and to maintain safe cargo handling work.
Further, the hydraulic oil path between the counterbalance valve and the control valve, by providing respectively provided with accumulator and different, of the accumulator to the individual hydraulic motors outlet of the two working oil passages, the energy of the pressure fluctuations at the outlet side of the hydraulic motor during downward movement of the stop and load hoisting device accumulates one Dana accumulator it is possible to use a winding energy during winding of the next, the energy of the cargo handling Efficiency is improved.

Further, according to the present invention, when the control valve is switched to neutral after winding up the load, the control port of the control valve is closed so that the control port of the control valve is closed. fall it is possible to prevent the cargo from the hydraulic fluid passage between the counterbalance valve and the control valve, the two working oil passages wherein the individual hydraulic motors outlet respectively provided with accumulator and different, of the by providing the accumulator, it can be alleviated pressure variation caused by switching of the control valve of the hydraulic oil passages leading to the control port of the control valve.

  Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this example are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.

FIG. 1 is a system diagram of a hydraulic drive device for a deck crane according to a first embodiment (reference example) of the present invention.
A deck crane that loads or unloads a load on a ship drives the hoisting device 1 that is directly connected to two directly connected tandem hydraulic motors 21 and 22 with the hydraulic drive device, thereby loading the load to the ship. Loading or unloading.
In FIG. 1, 9 is a hydraulic pump, 7 is a control valve, and hydraulic oil from the oil tank 10 is sent to the hydraulic motors 21 and 22 via the control valve 7 and the hydraulic oil passage 12 by the hydraulic pump 9. The hydraulic motors 21 and 22 are driven to drive the hoisting device 1 to wind up, neutralize and unwind.

The control valve 7 is normally constituted by a manual three-way switching valve, and the supply of the hydraulic oil to the hydraulic oil passage 12 connected to the hydraulic motors 21 and 22 is switched to cut off the hoisting device. The operation of 1 winding, neutral and unwinding is switched.
Reference numerals 3 and 3 are counter balance valves provided corresponding to the hydraulic motors 21 and 22. The counter balance valve 3 on one side is squeezed by the variable throttle 6 to flow the hydraulic oil branched from the hydraulic oil passage 12. Then, the pilot hydraulic pressure with reduced pressure is supplied, and the oil passage 14a at the hydraulic oil outlet of the hydraulic motor 22 on one side and the oil passage 14b to the control valve 7 are communicated or cut off.
The counter balance valve 3 on the other side is supplied with a pilot hydraulic pressure obtained by reducing the flow rate and pressure by reducing the hydraulic fluid branched from the hydraulic oil passage 12 with the variable throttle 6 and operating the hydraulic motor 21 on the other side. The oil passage 13 at the oil outlet and the oil passage 11 to the control valve 7 are communicated or blocked.

  Reference numerals 33 and 33 are check valves provided in the bypass passages of the counterbalance valves 3 and 3, respectively. 4 is a communication between the outlet oil passage 14 of the hydraulic motor 22 and the oil passage 11 to the control valve 7. The sequence valve 330 is a check valve provided in the outlet oil passage 14, and 8 is a hydraulic oil pressure adjusting valve at the outlet of the hydraulic pump 9.

  FIG. 4 is a longitudinal sectional view showing an example of a counter balance valve applied to the first embodiment and second to third embodiments described later. In FIG. 4, 35 is a valve case, 50 is a spool valve fitted in the fitting hole 38 of the valve case 35 so as to be slidable back and forth, 50a is a pilot piston provided at the lower end of the spool valve 50, Reference numeral 50b denotes a pilot oil chamber that the pilot piston 50a faces. 51 is a return spring of the spool valve 50, and 33 is a check valve (see FIG. 1).

In the hydraulic drive apparatus having such a spool valve type counter balance valve 3, when the control valve 7 is set at the winding position of the hoisting apparatus 1, the hydraulic oil branched from the hydraulic oil passage 12 as shown in FIG. When the pilot hydraulic pressure reduced by the variable throttle 6 to reduce the flow rate and pressure is introduced into the pilot oil chamber 50b and acts on the pilot piston 50a, the spool valve 50 is opened by the pilot piston 50a moving upward. As a result, the oil passage 40 communicates with the control oil chamber 38 and the oil passage 39, and the hydraulic motors 21, 22 and the control valve 7 side communicate with each other to enable the hoisting operation.
When the control valve 7 is switched to neutral after setting the load to the hoisting position, the pilot hydraulic pressure into the pilot oil chamber 50b is cut off, and the spool valve 50 is moved downward by the spring force of the return spring 51, and the oil The passage 40, the control oil chamber 38 and the oil passage 39 are shut off. As a result, the hydraulic pressure on the hydraulic motors 21 and 22 side is held at a constant hydraulic pressure, and the load suspended from the hoisting device 1 is held at a fixed height position.

In the first embodiment (reference example) of the present invention, in the hydraulic drive device of the deck crane, an accumulator 25 for absorbing negative pressure is installed in the hydraulic oil passage 12 for supplying hydraulic oil to the hydraulic motors 21 and 22. ing.
According to the first embodiment, after the control valve 7 is set at the winding position and the hoisting device 1 hoists the load by the hydraulic motors 21 and 22, the control valve 7 is switched from the neutral position to the unwinding position. When unloading the load, the hoisting device reverses due to the weight of the load, and the hydraulic motor performs a pumping action.

When a negative pressure is to be generated in the hydraulic oil passage 12 to the hydraulic motors 21 and 22 by the pump action of the hydraulic motors 21 and 22, an accumulator 25 provided at the inlet of the hydraulic motors 21 and 22 in the hydraulic oil passage 12. Supplies hydraulic oil into the hydraulic oil passage 12, so that the hydraulic oil is filled on the suction side of the hydraulic motors 21, 22 acting as a pump, and the negative pressure on the suction side of the hydraulic motors 21, 22 Inhalation of air can be avoided.
Thereby, when the hoisting device 1 unloads the load, the sudden drop of the load due to the idling of the hoisting device 1 can be prevented, and a safe cargo handling operation by the deck crane can be maintained.

FIG. 2 is a system diagram of a hydraulic drive device for a deck crane according to a second embodiment of the present invention.
In the second embodiment, the hydraulic motor 21, 22 of the hydraulic oil outlet and the hydraulic motor outlet side accumulator 25a of the two working oil passage 13 and 14 and a counterbalance valve 3, 3 respectively connected, 25b Is provided.
In such a second embodiment, provided in the hydraulic fluid passage 13, 14 between the hydraulic fluid outlet and the counterbalance valve 3, 3 of the hydraulic motor 21, 22 for driving the hoisting device 1 accumulator 25a, 25b, respectively Therefore, when the hoisting device 1 lifts the load by the hydraulic motors 21 and 22, when the control valve 7 is switched to the neutral position and the load is stopped at the hoisting position, the counter balance valves 3 and 3 are suddenly closed to cause the hydraulic motor It becomes a state in which peak oil pressure due to hydraulic pulsation is likely to be generated on the outlet sides of 21 and 22.

However, according according to the second embodiment, by accumulator 25a provided on the hydraulic oil outlet side of the hydraulic motor 21, 22, 25b to absorb the hydraulic pulsation, hydraulic motor 21 at winding stop position of the load, It is possible to avoid the occurrence of the peak hydraulic pressure at the 22 outlet side.
As a result, it is possible to prevent hydraulic oil leakage and breakage of the hydraulic oil system and to maintain safe cargo handling work.
Further, at the time of winding of the next energy pressure variation on an outlet side of the hydraulic motor 21 during the descent of the hoist 1 stop or cargo, such as, accumulated one Dana accumulator 25a, and 25b It can be used for hoisting energy, and the energy efficiency of the cargo handling work is improved.
The other structure is the same as that of FIG. 1 of the first embodiment (reference example), and the same members are denoted by the same reference numerals.

FIG. 3 is a system diagram of a hydraulic drive system for a deck crane according to a third embodiment of the present invention.
In the third embodiment, the control port 7a of the control valve 7 is set so as to be closed at the neutral position, and the two hydraulic oil passages 18 between the counter balance valve 3 and the control valve 7 are provided with the two pieces. each provided with accumulator 25a to the respective hydraulic motors 21.22 outlet of hydraulic fluid passages. 25b and is provided with the accumulator 5 of another different.
According to the third embodiment, after the hoisting device 1 lifts the load by the hydraulic motors 21 and 22, the control port 7a of the control valve 7 is set to be closed when the control valve 7 is switched to neutral. Thus, even when a slight amount of hydraulic oil leaks to the counterbalance valve 3 side, the control port 7a of the control valve 7 is closed, so that the load can be prevented from dropping from the position where the load is unwound, and the counter by the accumulator respectively provided to the hydraulic fluid path between the balancing valve 3 and the control valve 7, the switching of the control valve 7 of the hydraulic oil passage 18 leading to the control port 7a of the hydraulic fluid passage clogging control valve 7 The accompanying pressure fluctuation can be reduced.
The other structure is the same as that of FIG. 1 of the first embodiment (reference example), and the same members are denoted by the same reference numerals.

  According to the present invention, when the load of the deck crane is unloaded, the occurrence of the slide of the load of the deck crane that avoids the generation of negative pressure in the hydraulic oil supply path to the hydraulic motor is prevented, and the control is performed after the load is wound up. It is possible to provide a hydraulic drive device that can reduce the peak hydraulic pressure caused by hydraulic pulsation when the load is stopped at the hoisting position by the valve and can realize a safe cargo handling operation.

1 is a system diagram of a hydraulic drive device for a deck crane according to a first embodiment of the present invention. It is a systematic diagram of the hydraulic drive apparatus of the deck crane which concerns on 2nd Example of this invention. It is a systematic diagram of the hydraulic drive apparatus of the deck crane which concerns on 3rd Example of this invention. It is a longitudinal cross-sectional view which shows an example of the counter balance valve applied to the said 1st-3rd Example. It is a systematic diagram of the hydraulic drive apparatus of the deck crane which concerns on a prior art.

DESCRIPTION OF SYMBOLS 1 Hoisting device 3 Counter balance valve 6 Variable throttle 7 Control valve 8 Pressure regulating valve 9 Hydraulic pump 21, 22 Hydraulic motor 25, 25a, 25b Accumulator 33 Check valve

Claims (2)

A hydraulic drive device for a deck crane that is installed on a ship and is loaded or unloaded on a ship by a hoisting device that is directly connected to a hydraulic motor, and is supplied with hydraulic oil from a hydraulic pump to the hydraulic motor A control valve for switching the hoisting, neutral and unwinding operations of the hoisting device is provided on the road, and is connected to the hydraulic oil passage of the hydraulic motor outlet and between the hydraulic motor outlet and the control valve by pilot hydraulic pressure. In the hydraulic drive device for a deck crane having a counterbalance valve for opening and closing the hydraulic oil passage, a tandem hydraulic motor in which two hydraulic motors are connected in series is formed, and the counterbalance valve is connected to the tandem hydraulic motor. Two accumulators are provided corresponding to each of the tandem hydraulic motors and the front Respectively and two counterbalance valve on each of two hydraulic fluid passage connecting said to two outlet side of the individual hydraulic motors of the hydraulic oil path, the accumulator is provided respectively,
When the hoisting device hoists the load by the hydraulic motor, the two hydraulic oil passages are switched to the neutral position by switching the control valve to neutral and stopping the load at the hoisting position. Configured to generate a peak hydraulic pressure due to hydraulic pulsation on the outlet side of the
The accumulator provided separately to the two working oil passage said, the energy of the outlet side of the pressure variation of the hydraulic motor at the time of stop of the hoisting device, once accumulated in the accumulator winding energy during winding of the next A deck crane hydraulic drive characterized by being configured to be used. The control port of the control valve is set to be closed at the neutral position, and the hydraulic oil passage between the counter balance valve and the control valve is set at the outlet of each of the hydraulic oil passages of the two hydraulic oil passages. hydraulic drive system of the deck crane of claim 1, characterized in that a accumulator and different, of the accumulator provided.

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