JPS58135097A - Safety device for hydraulic driving winch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safety device for a hydraulically driven winch.

Generally, a hydraulically driven winch is driven by a single hydraulic motor, but as the winch capacity increases, a large capacity hydraulic motor is required. However, since large-capacity hydraulic motors are not currently available on the market, two hydraulic motors are used. In this case, it is necessary to equalize the loads on the two hydraulic motors, and for this purpose, conventionally, a hydraulic circuit as shown in FIG. 4 has been used.

That is, in the past, two hydraulic motors s' and 6' were connected to each output shaft 5-63' for one winch drum 7'.
The counterbalance valves 3' and 4' are provided in the lower oil outflow side passages 34' and 44' of each hydraulic motor 5' and 6', respectively, and the first counterbalance valve 6'
is opened and closed by pilot pressure from the hoisting oil inlet flow path 65' of the first hydraulic motor 5', and the second counterbalance valve 4' is operated by the first hydraulic motor 5' and the first counterbalance valve 3'. The load pressure of the first hydraulic motor 5' is taken out by the tuning pilot line 92' from the flow path 64' between the second hydraulic motor 6' and the second counterbalance valve 4'. The opening/closing operation is performed by a pressure difference between the load pressure of the second pressure motor 6' and the load pressure of the second pressure motor 6' taken out from the pilot flow path 46'. In this way, a pilot line 92' is provided to synchronize the two hydraulic motors 5' and 6', but conventionally, if this line 92' is damaged, the counterbalance valve 4- is blocked. There was a safety defect in that the function was lost and the suspended load 71' fell.

The present invention eliminates these drawbacks and provides a safety device that can automatically lock the drum and prevent the suspended load from falling even if the tuning pilot line is damaged.

That is, the feature of the present invention is that the output shaft of @1 hydraulic motor and the output shaft of second hydraulic motor are mechanically connected to one winch drum, and oil leakage from the first hydraulic motor is prevented. A first counterbalance valve that is opened and closed by the pressure of the lower oil inflow side flow path is provided in the middle of the side flow path, and a first counterbalance valve that is operated to open and close by the pressure of the lower oil inflow side flow path of the second hydraulic motor is provided. a second counter that is opened and closed by a pressure difference between the load pressure of the first hydraulic motor and the load pressure of the second hydraulic motor, which are guided from the flow path between the first counterbalance valve and the second hydraulic motor through a tuning pilot conduit; A balance valve is provided, and a hydraulic negative brake is provided on the drum or a member mechanically connected thereto, and a brake pipe for supplying pressure oil to a cylinder for releasing this negative brake, and a middle of the tuning pilot pipe. The switching valve is actuated by the pressure difference between the image adjustment pilot pipe before and after the switching valve, and when there is no pressure difference, it is in the normal position and the switching valve moves from the first hydraulic motor side to the second counter balance. Pilot pressure is introduced to the valve, and pressure oil is also introduced from the hydraulic source to the release cylinder to release the negative brake, so that the pilot line pressure on the second counterbalance valve side is higher than the pilot pressure on the first counterbalance valve side. When the pressure becomes low, it is switched to the offset position to block the tuning pilot line, block the supply of pressure oil from the hydraulic source to the release cylinder, and release the pressure oil in the release cylinder to the tank. There is a safety device on a hydraulically driven winch configured to do so.

The present invention will be explained below based on the embodiments shown in FIGS. 1 to 3.

1 is a hydraulic pump, 2- is a directional control valve, 6 is a first counterbalance valve, 4 is a second counterbalance valve, 5 is a first hydraulic motor, 6 is a second hydraulic motor, 7 is a winch drum, and 8 is a Negative brake, 9 indicates the switching valve, these are the first
They are connected as shown in the figure.

By switching the directional control valve 2, the oil discharged from the hydraulic pump 1 is delivered to the two hydraulic motors 5. It is supplied to the hoisting oil inflow side (=hoisting oil outflow side) channel 51.61 or the hoisting oil inflow side (=hoisting oil outflow side) channel 52.62 of B. 11 is a ura tank, and 12 is a main relief valve.

Both hydraulic motors5. B's output shaft 53. ,! S3 is mechanically connected to a winch drum 7, which is provided with a negative brake 8. The opening cylinder 84 of the negative brake 8 is opened by pressure oil supplied from the hydraulic power source 81 through the pipe line 82, the switching valve 9, and the pipe line 83. 85 is a return oil pipe line from the cylinder 84 to the oil tank 86.

On the other hand, the counterbalance valves 3 and 4 are operated by hydraulic motors 5 and 6.
It is directly connected to the check valve 31゜41, has a plunger 62.42, and has an overload relief valve 33.43 built-in.
．． 41 and a flow path 34,4 with a plunger 32.42
4 to the lower oil inflow port 53.61 of the motor 5゜6, and the other flow path 35.45 to the other port 52.6.
Connected to 2. The plunger 32 of the first counterbalance valve 6 is opened and closed by the pilot pressure taken out from the flow path 35 through the pilot flow path 3B. The plunger 41 of the second counterbalance valve 4 is connected to the pilot pressure taken out by the flow path 44 between the boat 4 and the second hydraulic motor 6 through the Rahailot flow path 46, and the first counterbalance valve 3 and the first hydraulic motor 5. from the flow path 64 between the pilot flow path 3
7. The switching valve 9 is opened and closed by the pressure difference between it and the pilot pressure taken out through the pilot pipe 92.

The switching valve 9 is directly connected to the first counterbalance valve 6 , and the spool 91 of the switching valve 9 receives the pilot pressure taken out from the flow path 37 through the pilot flow path 96 and the pilot pipe 9 .
It is switched by the pressure difference between the pilot pressure taken out from the pilot flow path 94 from the spool 91 and the pilot pressure taken out from the pilot flow path 94 from the spool 91.
A constricted portion 96 is provided at a portion where the pipe 7 and the pipe 92 communicate with each other.

Next, the effect will be explained.

Now, when the pilot line 92 is normal, the switching valve 9 is moved by the spring 95 to the normal position shown in FIG.
In the state shown in the figure, the first counterbalance valve 3 and the first
The load pressure between the hydraulic motor 5 passes from the pilot flow path 37 through the constriction part 96 in the switching valve 9, and passes through the pilot flow path 92.
It is led to the second counterbalance valve 4 via. In this state, the flow rate of the flow gutter flowing into the pilot pipe line 92 is not large enough to generate a pressure difference before and after the constriction part 96 of the switching valve 9, and therefore the switching valve 9 is moved to the normal state by the spring 95. The switching valve 9 remains in this position, and the switching valve 9 is in the same state as if it were not present. 1 When the switching valve 9 is in the normal position as described above, pressure oil from the pressure source 81 is guided to the opening cylinder 84 of the negative brake 8 via the pipe 82, the switching valve 9, and the pipe 86, and the negative brake is released. 8 is in the open state.

When the directional control valve 2 is switched to the 8th position during the hoisting operation, the oil discharged from the hydraulic pump 1 flows in the directions of arrows AI and A2, and the oil flows through the pipes 21 and 22 and the counterbalance valves 6 and 4. Each hydraulic motor 5.
The hydraulic motors 5 and 6 are driven with the same pressure, and accordingly, the winch drum 7 rotates in the hoisting direction, and the suspended load 71 is hoisted. In addition, each hydraulic motor 5, 6
The return oil from arrow A3. Guided in the A4 direction, conduit 26
24 and the directional control valve 2 and then returned to the tank 11.

Next, when the directional control valve 2 is switched to the 5th position during the lowering operation, the oil discharged from the hydraulic pump 1 flows in the direction of the arrows B1 and B2, passing through the pipes 23 and 24 and the flow path 35.45. into each hydraulic motor 5.6.

At this time, initially the flow path 3 on the outflow side of each hydraulic motor 5, 6
4.44 is blocked by the counterbalance valves 3 and 4, so the pressure in the flow paths 35 and 45 on the inflow side gradually increases while the hydraulic motors 5 and 6 remain stopped. Along with this, in the first counterbalance valve 3, the pressure in the flow path 35 is changed to the plunger 3 via the i4 pilot flow path 66.
This pressure causes the plunger 32 to
, the flow path 64 on the outflow side of the first hydraulic motor 5, which is under surface pressure due to the load of the drum 7, is opened, and the oil in the flow path 34 is released into the pipe line 21. , arrow B3
The oil is guided in the direction and circulated to the oil tank 11, and the first hydraulic motor 5 is rotated in the lowering direction. At this time, the load pressure of the first hydraulic motor 5 is transferred from the flow path 34 to the plunger 42 of the second counterbalance valve 4 via the switching valve 9 and the pilot pipe 92.
is guided on the right side of the drawing.

On the other hand, when the first hydraulic motor 5 is rotated in the lowering direction, its load pressure decreases, and at the same time, the second hydraulic motor 6
As the load pressure increases, the pressure in the outlet flow path 44 increases, and this pressure is guided to the drawing side of the plunger 42 through the pilot flow path 46. At this time, since the load pressure of the second hydraulic motor 6 guided to the left side of the drawing of the plunger 42 is higher than the load pressure of the first hydraulic motor 5 guided to the right side of the plunger 42, the plunger 42 is pushed down to the right side of the drawing. The flow path 44 is opened, and the pressure oil in the flow path 44 is guided in the direction of arrow B4 and circulated to the oil tank 11, thereby rotating the second hydraulic motor 6 in the lowering direction. .

In this way, the second counterbalance valve 4 is opened and closed by the pressure difference between the load pressures of the second hydraulic motor 6 and the first hydraulic motor 5 guided to the left and right sides of the plunger 42, and the load pressure of the former is increased more than the load pressure of the latter. If the pressure becomes too much, the flow path 44 is opened to allow the pressure oil to flow out, and if the pressure oil in the flow path 44 is allowed to flow out too much and the load pressure in the former becomes smaller than the load pressure in the latter, the flow path 44 is blocked. Or narrow it down and use both sleeve pressure motors 5. 5. The load pressure of B is always controlled equally, and both sleeve pressure motors are used in lowering operation. This eliminates the imbalance in the load on B.

However, if the pilot pipe line 92 is damaged during each of the above operations and in the state in which the suspended load is held after the operation is stopped,
The conduit 92 is opened to the atmosphere. Therefore, the plunger 42 of the second counterbalance valve 4 is pushed down to the right in the drawing by the load pressure of the second hydraulic motor 6, the flow path 44 is opened, and the pressure oil in the flow path 44 is transferred to the oil tank 11 side. leaked,
The second hydraulic motor 6 attempts to rotate in the lowering direction, but at this time, the switching valve 9 immediately switches to the off-seller 1. The negative brake 8 is activated and the drum 7 is braked. That is, when the pilot pipe 92 is damaged and opened to the atmosphere, the pressure in the pilot flow path 94 decreases to atmospheric pressure, and the pilot flow path 94 is guided to the upper end side of the switching valve 9 via the pilot flow path 37.93. Due to the load pressure of the first hydraulic motor 5, the spool 91 of the switching valve 9 is switched to the offset position, that is, the upper position, against the spring 95, resulting in the state shown in FIG. As a result, the pilot passage 67 is blocked, and the supply of pressure oil from the hydraulic pressure source 81 to the release cylinder 84 of the negative brake 8 is blocked, and
The pressure oil in the opening cylinder 84 is transferred to the pipe line 83, the switching valve 9,
It is opened to an oil tank 86 via a conduit 85, whereby the negative brake 8 is activated, and the drum 7 is braked to prevent the suspended load 71 from falling.

As explained above, according to the present invention, during the lowering operation,
This is a device that can always synchronize two hydraulic motors for smooth lowering operation, and in particular, if the pilot line for synchronizing both pressure motors is damaged, the switching valve can be automatically switched. Immediately activate the negative brake,
The winch drum can be locked to prevent suspended loads from falling.
This can improve safety.

[Brief explanation of the drawing]

The first Fi+ is a hydraulic circuit diagram showing an embodiment of the present invention, and the second Fi+ is a hydraulic circuit diagram showing an embodiment of the present invention.
The figure is a hydraulic circuit diagram of the main parts embodying the switching valve, and FIG. 3 is a sectional view of the switching valve showing the switching state of the switching valve.
FIG. 4 is a hydraulic circuit diagram of a conventional hydraulically driven winch. DESCRIPTION OF SYMBOLS 1... Hydraulic pump, 2... Direction control valve, 3... First counterbalance valve, 4... Second counterbalance valve, 5... First hydraulic motor, 6... Second Hydraulic motor, 7... winch drum, 8... negative brake,
9... Switching valve, 81... Hydraulic power source, 84... Opening cylinder, 92... Tuning pilot pipe line. Patent applicant Kobe Steel Corporation, patent attorney Etsushi Kotani. (. ,, Ql , 1.' Fig. 2 Fig. 3

Claims (1)

[Claims] 1. The output shaft of the first hydraulic motor and the output shaft of the second hydraulic motor are mechanically connected to one winch drum, and in the middle of the flow path on the oil outflow side of the first volume of the first hydraulic motor, A first counterbalance valve is provided which is opened and closed by the pressure of the lowering oil inflow side passage, and a first counterbalance valve is provided between the first hydraulic motor and the first counterbalance valve in the middle of the lowering oil outflowing side passage of the second hydraulic motor. The first channel led from the flow path between the
A rod 2 counter balance valve is provided which is opened and closed by a pressure difference between the load pressure of the hydraulic motor and the load pressure of the second hydraulic motor, and a hydraulic negative brake is provided on the drum or a member mechanically connected thereto. A switching valve is provided in the middle of the brake line that supplies pressure oil to the negative brake release cylinder and in the middle of the tuning pilot line, and the switching valve controls the pressure of the tuning pilot line before and after the brake line. When there is no pressure difference, it is in the normal position, and pilot pressure is guided from the first hydraulic motor side to the second counterbalance valve, and pressure oil is guided from the hydraulic source to the opening cylinder to create a negative When the brake is released and the pilot line pressure on the second counterbalance valve side becomes lower than the pilot pressure on the first counterbalance valve side, the tuning pilot line is switched to the offset position and blocked. , a safety device for a hydraulically driven winch characterized by a Kokichi device configured to block the supply of pressure oil from a hydraulic source to an opening cylinder and release pressure oil in the opening cylinder to a tank.