JPS58183590A - Controller 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 control device for a hydraulically driven winch.

Generally, a hydraulic winch is provided with a clutch device that transmits the driving force of a winch drum drive motor to the winch drum, and a brake device that brakes the drum from idling. Moreover, as a brake device, one using a positive brake device and one using a negative brake device are publicly known.

However, conventionally, the brake device is operated by a brake pedal provided separately from the operating lever of the clutch device. It is necessary to operate both the clutch operating lever and the brake pedal during each control (descent), which poses a problem of poor operability.

In particular, with positive braking devices, the brakes are applied by the normal brake operation of depressing the brake pedal, so the brake operation itself is easy and has the advantage of being easy to control free fall, but it is difficult to perform any operation. If not, the suspended load will fall when the brake is off (released), so it is necessary to lock the pedal etc. with a locking mechanism with the brake on, and release the locking mechanism before and after operating the brake. There is a risk that the suspended load will fall due to this movement.

In addition, with a negative brake device, if no operation is performed, the brake is turned on by the spring force, so it is possible to completely hold the suspended load, and even if the brake is activated by mistake, if the brake operation is released, the brake will be turned on automatically. However, when controlling free fall, the brake pedal must be lifted to apply the brakes, which is the opposite of a normal brake operation, making it difficult to control.

The present invention was made in order to solve the above-mentioned conventional problems, and the clutch device and the negative brake device can be easily turned on and off using a common work switching valve and operation lever.
When the winch operation is stopped, the hydraulic oil in the clutch device and the hydraulic oil in the negative brake device are released into the tank to turn on the clutch, and the brake is turned on to stop the winch drum. To reliably prevent suspended loads from falling, during winch work, pressure oil is guided from a second pressure oil source separate from the drive pressure oil source of the winch drum drive motor to the clutch device and negative pre-pinch device. The clutch is turned on and the brake is turned off, and the driving force of the winch drum motor is transmitted to the winch drum so that the drum can be driven smoothly.In the case of free fall, the hydraulic oil of the clutch device is released to the tank, and the hydraulic oil is released from the second pressure oil source. To provide a control device for a hydraulically driven winch, which allows free fall work to be performed by guiding pressure oil to a negative brake device to turn on the brake.

Hereinafter, the present invention will be explained based on embodiments shown in the drawings.

Pl is a first pump as a first pressure oil source, and its discharge circuit 10 is connected to both side circuits 14+15 of the winch drum drive motor M and a discharge circuit 16 to the tank T via the first control valve 1. Connected freely. The first control valve 1 includes a first relief valve 11, a pilot valve 12 for merging surplus oil from other actuator circuits such as boom elevation of a hydraulic crane, and a rotational direction of the motor M, that is, a winding direction. It is equipped with a winding direction switching valve 16 for switching the winding direction. The winding direction switching valve 16 can be freely switched between a neutral position 13a where the motor M is stopped, a position 131) where the motor M is rotated in the winding direction, and a position 15Q where the motor M is rotated in the winding down direction. Nodame operating lever 16d and automatic return spring 16e for holding in neutral position 13a.

It is equipped with 13f. 17 is a counterbalance valve, 1
8.19 shows the pilot circuit.

P2 is a second pump as a second pressure oil source, and its discharge circuit 20 includes a check valve 21, a second relief valve 22,
The motor M is connected to the motor M via a second control valve v2 having a work switching valve 25 and a pilot switching valve 24.
A clutch circuit 31 of the clutch device 30 that transmits the driving force of the winch drum 5o to the winch drum 5o is connected to a brake circuit 41 of the negative brake device 40 that brakes the winch drum 50 from idling.

Note that the second pump P2 is a pressure oil source for controlling the clutch and brake as described later, but is smaller (lower capacity, lower discharge pressure) than the first pump P1 for driving the motor M for collection. It's fine to use one.

The work switching valve 23 has a drum stop neutral position 23a where the hydraulic oil in the clutch device 6o and the hydraulic oil in the negative brake device 4o are guided to the tank T, and the winch drum 50 is stopped by turning off the clutch and turning on the brake. Pressure oil from the second pump P2 is introduced to the clutch device 3o and the negative brake device 4o, and the clutch is turned on and the brake is turned off to transfer the driving force of the motor M to the winch drum 5o.
drum drive position 26b and clutch device 50
A free-fall position 23C in which the hydraulic oil from the 26th pump P2 is guided to the tank T to turn on the clutch, and pressure oil from the 26th pump P2 is guided to the negative brake device 4o to turn off the brake and enable the winch drum 50 to free fall. It can be freely switched from the free fall position 25Q to the neutral position 23 using the switching operation lever 25d.
a spring 26θ for automatically returning to the neutral position 25
FL and a positioning means 23f for holding the position at the drum drive position 23b.

Further, the pilot switching valve 24 is connected to the driving pressure of the motor M, that is, from the both-side circuit 14.15 to the pilot circuit 18.1.
When the pressure difference is small, it is held at the neutral position 24a by springs 24d and 24θ, and when the pressure difference exceeds a predetermined value, it is switched to the right position 241) or the left position. 240. However, the spool hole shapes at the left and right switching positions 241) and 24Q are formed the same. 26 is an auxiliary circuit, and 27 is an accumulator.

60 is a positive brake device, and the clutch circuit 5
1 and the negative brake circuit 41, and is configured to transmit the depression force of the brake pedal 61 to the brake cylinder via the master cylinder 62. Reference numeral 66 indicates a positive brake pressure oil source. This source of pressure oil 66 may be derived from the drain/circuit.

Next, the effect will be explained.

First, when any operation is too forceful, the winding direction switching valve 15 is held in the neutral position by the spring 13113.13f, and the oil discharged from the first pump P1 is guided in the direction of arrow A1 and returned to the tank T. Motor M is stopped. At this time, since no pressure is introduced into the pilot circuits 18, 19, the pilot switching valve 24 is held at the neutral position 24a. On the other hand, the work switching valve 26 also has a spring 25e and a positioning means 26f.
is held at the neutral position 23a. Therefore, the hydraulic oil in the clutch device 30 and the hydraulic oil in the negative brake device 40 are guided in the directions of arrows A2 and A3, and are returned to the tank T via the work switching valve 26 and the pilot switching valve 24, and then When the clutch device 60 is in the clutch-off state and each negative brake device 40 is in the brake-on state by its own spring force, the winch drum 50 is held in a stopped state without idling, and the lifting equipment and The suspended load will not fall.

Note that when the winch drum 50 is stopped, the oil discharged from the second pump P2 is guided in the direction of arrow A4, passes through the pilot switching valve 24 and the auxiliary circuit 26, and then flows into the accumulator 27.
After a predetermined pressure is accumulated in the accumulator 27, the discharged oil is returned to the tank T via the second relief valve 22.

Next, when performing the winding operation, the work switching valve 23 is switched to the sitram drive position 25b by its operating lever 25d, and then the winding direction switching valve 13 is switched to its operating lever 13 (to the winding position 131 by l).

Accordingly, first, the oil discharged from the second pump P2 is
direction, flows into the clutch device 60 for Shimaki, and is clutched on. Thereafter, the oil discharged from the first pump P1 is guided in the direction of arrow B2, flows into the motor M, and attempts to drive the motor M. However, since the pressure on the inflow side of the motor M is initially low, the pilot switching valve 24 is in the neutral position 241L, and therefore the working oil in the negative brake device 40 is guided in the direction of the arrow B port and the tank T The brake device 40 is in a brake-on state due to its own spring force, and the winch drum 50 is stopped.

After that, when the pressure on the inflow side of the motor M becomes equal to or higher than a predetermined pressure, the pressure is guided from the circuit 14 through the pilot circuit 18 in the direction of arrow B4, and the pilot switching valve 24 is switched to the right position 241). Accordingly, the oil discharged from the second pump P2 is guided in the direction of the arrow B1 and the direction of the arrow B5, flows into the clutch device 60 to turn on the clutch, and flows into the negative brake device 40 to turn off the brake. The motor M rotates in the hoisting direction, and its rotational force is transmitted to the winch drum 50 via the power transmission mechanism 51 and the clutch device 3o, and the winch drum 50 performs the hoisting operation. At this time, the oil discharged from the motor M is guided in the direction of arrow B6 and returned to the tank T.

In such a case, when the pilot switching valve 24 is omitted and the work switching valve 25 is switched to the winch drum drive position 21b, the discharge oil of the second pump P2 is guided to the clutch device 50 and the clutch is turned on, at the same time as the negative brake is activated. Even if the brake is turned off by directing the suspension to the device 40, the counterbalance valve 17 can prevent the hanging tool and the suspended load from falling.

Next, when performing free fall, the winding direction switching valve 16
is returned to the neutral position 13a, and the work switching valve 26 is switched to the free fall position 23C. By this, the first pump P
The discharged oil of No. 1 is guided in the direction of arrow C1 and returned to tank T, and motor M is stopped. On the other hand, the oil discharged from the second pump P2 is guided in the direction of arrow C2 to the negative brake device 4.
0, the brake device 40 is turned off, and the hydraulic oil in the clutch device 30 is guided in the direction of arrow C3 and returned to the tank T, and the clutch device 60 is turned off. , the hanging tool and the hanging load freely descend while causing the winch drum 50 to idle due to their own weight.

During this free fall, by stepping on the brake pedal 61 of the positive brake device 60 to turn on the brake, the winch drum 50 can be stopped, and the hanging tool and the suspended load can be stopped at any position.

However, in the present invention, the lever 23d.

If you return the work switching valve 25 to the neutral position 23a by operating the
The working oil in the clutch device 60 and the working oil in the negative brake device 40 are returned to the tank T, and the clutch is automatically turned off and the brake is turned on.Then, the wind drum 50 is stopped, and the lifting tool and the brake are turned on.

Since the suspended load is stopped, there is no need to press the brake pedal 61 of the positive brake device 60.
Therefore, the positive brake device 60 may be omitted. In this case, the work selector valve 23 is suddenly moved to the neutral position 2.
If it is returned to 6a, the shock at stop will be large, so the spool shape of the work switching valve 26, etc. may be devised, and the brake may be gradually applied by, for example, gradually returning the lever 23d to neutral.

Also, during this free fall, the lever 23a is switched against the spring 25e, so when the lever 2311 is released, the work switching valve 26 is automatically returned to the neutral position 23a by the spring 23f3, and the clutch is automatically turned off and Since the brake is turned on, the lifting equipment and the suspended load will not fall unexpectedly, making it safe.Even when using a positive brake device, the brake pedal can be pressed and the brake turned on as in the conventional case. There is no need to lock with the locking mechanism, and the locking mechanism can be omitted.

In addition, when performing the lowering operation, the operation switching valve 26 may be switched to the drum drive position 231) as in the case of winding, and the winding direction switching valve 13 may be switched to the lowering position 13C.

As explained above, according to the present invention, both the clutch device and the brake device can be easily turned on and off by operating the lever of one work switching valve, and the drive, stop, and free fall of the winch can be easily controlled. This allows for improved operability.

[Brief explanation of the drawing]

The drawing is a circuit diagram showing an embodiment of the present invention. Pl...first pressure oil source (first pump), P2...second
Pressure oil source (second pump), ■1...first control valve, v2.
...Second control valve, M...Winch drum drive motor,
T... Tank, 15... Winding direction switching valve, 13a...
・Neutral position, 15b...Hoisting position, 13C...Lowing down position, 13d...Operation lever, 13eyi3f・
...Spring, 17...Counterbalance valve, 25...
Work switching valve, 26a... Neutral position for drum stop, 26
b...Drum drive position, 25C...Free fall position, 24...Pilot switching valve, 60...Clutch device, 40...Negative brake device, 50...
・Winch drum. Patent applicant: Kobe Steel, Ltd. 14-

Claims (1)

[Claims] 1. A winding direction switching valve that guides pressure oil from a first pressure oil source to a winch drum drive motor, and a winding direction switching valve that guides pressure oil from a second pressure oil source to a clutch device and a negative brake device of the winch drum. The work switching valve has a neutral position for stopping the winch drum, where the hydraulic oil in the clutch device and the hydraulic oil in the negative brake device are guided to the tank to turn off the clutch and turn on the brake, and a neutral position for stopping the winch drum. A winch drum drive position that leads pressure oil from a two-pressure oil source to a clutch device and a negative brake device to turn on the clutch and brake, and a winch drum drive position that leads hydraulic oil in the clutch device to a tank to turn on the clutch and a second pressure oil source. 1. A control device for a hydraulically driven winch, characterized in that the control device is configured to be able to freely switch between a free fall position where pressure oil from a source is guided to a negative brake device and the brake is turned off. 1-