JPH11130381A - Method and device for controlling hydraulic winch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regulate a free-fall speed while securing an original free-fall function. SOLUTION: A brake hydraulic pump 24 is connected to a winch drum 1 by a one-way clutch 23, the brake hydraulic pump 24 is driven by the winch drum 1 during free-fall running, and by supplying the discharge oil of the pump 24 to the cylinder 11 of a hydraulic brake 12 so as to apply a braking force on the winch drum 1, a free-fall speed is regulated. Also, by supplying pump discharged oil to a brake heat generation part through a cooling pipeline 27, the brake heat generation part is cooled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for controlling a hydraulic winch in which a winch drum is driven by a hydraulic motor.

[0002]

2. Description of the Related Art A conventional technique is shown in FIG.

In FIG. 1, reference numeral 1 denotes a winch drum, and 2 denotes a hydraulic motor (hereinafter referred to as a winch motor) as a drive source of the winch drum 1.
A planetary gear mechanism 3 for transmitting power between the output shaft 2a and the winch drum 1 is provided.

Reference numeral 4 denotes a sun gear of the planetary gear mechanism 3, reference numeral 5 denotes a planetary gear, reference numeral 6 denotes a ring gear provided on the inner periphery of the winch drum 1, reference numeral 7 denotes a carrier for supporting the planetary gear 5, reference numeral 8 denotes a carrier shaft, and reference numeral 8 denotes a carrier shaft. A multi-plate clutch 9 is provided at the shaft end of the motor. The multi-plate clutch 9, a piston 10 that presses and separates from the clutch 9, and a cylinder 11 that drives the piston 10 cause the winch drum 1 to output a motor output. Connected and separated from the shaft 2a,
Further, a hydraulic brake 12 for braking the rotation of the drum 1 is configured.

A spring 13 presses the piston 10 in a direction in which the piston 10 is pressed against the multi-plate clutch 9.

[0006] An extension side pipe line 14 connected to the extension side oil chamber 11 a of the cylinder 11 is connected to a secondary side of a brake valve (pressure reducing valve) 16 operated by a brake pedal 15.

[0007] A reduction-side pipe 17 connected to the reduction-side oil chamber 11b of the cylinder 11 is connected to a hydraulic source 19 and a tank T via an electromagnetic switching valve 18 as switching means.

During normal operation, the electromagnetic switching valve 18 is at the normal operation position a on the left side of the figure, and in this state, the cylinder reduction side oil chamber 11b communicates with the tank T.

On the other hand, the switch 20 is turned on during a free fall operation in which the winch drum 1 is rotated down by a load (hanging load), whereby the electromagnetic switching valve 18 is switched to the free fall operation position b on the right side in the figure. In this state, the cylinder reduction side oil chamber 11b is connected to the hydraulic pressure source 19.

This device works as follows.

(A) Normal hoisting / unwinding operation At this time, the electromagnetic switching valve 18 is at the normal operating position a in the figure, and no pressure is generated in the cylinder reduction side oil chamber 11b.

Further, at this time, since the brake pedal 15 is not operated, no secondary pressure is generated in the brake valve 16, and no pressure is generated in the cylinder extension side oil chamber 11a.

Therefore, the force of the spring 13 causes the piston 10
Is pressed against the clutch 9 and the clutch 9 is fixed to the fixing portion, so that the carrier shaft 8 is non-rotatably fixed.

In this state, the planetary gear 5 of the planetary gear mechanism 3 rotates only by itself, and the rotational force of the winch motor 2 is reduced by the planetary gear mechanism 3 and transmitted to the winch drum 1, and the normal power hoisting / winding is performed. Lower operation is performed.

When the rotation of the winch motor 2 stops, the winch drum 1 is fixed by the planetary gear mechanism 3 so that it cannot rotate.

(B) Free fall operation At this time, with the winch motor 2 stopped, the switch 20 is operated to switch the electromagnetic switching valve 18 to the free fall operation position "b", and the cylinder reduction side oil chamber 11b
Is pressured.

As a result, the cylinder 11 is contracted, the piston 10 is separated from the clutch 13 and the carrier shaft 8
Becomes free (the hydraulic brake 12 is released), and the winch drum 1 freely rotates in the lowering direction at a speed according to the load.

At this time, when the brake pedal 15 is operated and a secondary pressure is generated in the brake valve 16, the oil chamber 11a on the cylinder extension side is pressurized and the piston 10 is pressed against the clutch 9, so that the above-described power hoisting / power-up operation is performed. It becomes the same state (clutch on state) as during the lowering operation.

Thus, a braking force corresponding to the operation amount of the brake pedal 15 acts on the winch drum 1, and the free fall speed is adjusted by the operator.

On the other hand, the suspended load descending speed during the free fall operation is considerably faster than that during the power unwinding. Since the speed is adjusted while applying the braking force of the hydraulic brake 12 as described above, Piston 10
Then, a friction portion of the clutch 9 (hereinafter, referred to as a brake heat generating portion) generates heat.

Therefore, the oil discharged from the hydraulic pump 21 driven by an engine (not shown) is sent to the above-mentioned heat generating portion for cooling.

[0022]

However, according to the above prior art, the speed adjustment operation by the operator is required during the free fall operation, and this operation must be performed carefully, which imposes a heavy operation burden on the operator. Had become.

Further, there is a possibility that the suspended load may fall freely and freely against the intention of the operator due to an operator's brake operation error.

Therefore, as a countermeasure against this point, Japanese Unexamined Patent Application Publication No.
As shown in JP-A-12280, a hydraulic pump for braking is connected to the winch drum 1 and a relief valve is connected to the pump to form a hydraulic load circuit. There has been proposed a technique in which the free-fall speed is regulated by applying rotational resistance to the winch drum by the above-mentioned hydraulic load circuit by rotationally driving.

However, according to this known technique, a large pump is required in order to obtain a sufficient load resistance even for a large load, and the set pressure of the relief valve needs to be relatively high.

For this reason, the winch drum 1 does not rotate under the load (the free fall cannot be performed) at the time of the small load including the idle hook.

For this reason, this known technique has not been practically feasible.

Accordingly, the present invention provides a hydraulic winch control method and apparatus capable of regulating the free fall speed while securing the original free fall function.

[0029]

According to a first aspect of the present invention, a hydraulic brake is provided on a winch drum that is rotationally driven by a hydraulic motor, and the operation mode is controlled by:
In a hydraulic winch provided with switching means for switching between a normal hoisting and lowering operation in which the winch drum is rotated by the hydraulic motor and a free fall operation in which the winch drum is rotated downward by a load, the rotary drive by the winch drum A hydraulic pump for braking, which limits the maximum rotation speed of the winch drum by applying pressure oil from the hydraulic pump for braking to the driving portion of the hydraulic brake in the brake operating direction during the free fall operation. It is.

According to a second aspect of the present invention, in the method of the first aspect, the pressure oil from the brake hydraulic pump is supplied as cooling oil to the heat generating portion of the hydraulic brake in parallel with the drive portion of the hydraulic brake. .

According to a third aspect of the present invention, there is provided a control device wherein a hydraulic brake is provided on a winch drum rotatably driven by a hydraulic motor, and an operation mode is set to a normal winding / winding mode in which the winch drum is rotated by the hydraulic motor. In a hydraulic winch provided with a switching means for switching between a lower operation and a free fall operation in which a winch drum is rotated downward by a load, a hydraulic pump for braking is rotationally driven by the winch drum at least during the free fall operation. Pressure generating means is provided in the discharge line of the hydraulic pump for pump so that the hydraulic pressure generated in the discharge line of the hydraulic pump for brake is applied to the hydraulic brake in the brake operating direction. Are connected to the drive unit of the hydraulic brake.

According to a fourth aspect of the present invention, in the configuration of the third aspect, a valve having a variable set pressure is used as the pressure generating means.

According to a fifth aspect of the present invention, in the configuration of the third or fourth aspect, the discharge oil of the brake hydraulic pump can be supplied as cooling oil to the heat generating portion of the hydraulic brake in parallel with the drive portion of the hydraulic brake. In addition, a cooling pipe is connected between the pump discharge pipe and the heat generating portion of the hydraulic brake.

According to a sixth aspect of the present invention, in the configuration of the fifth aspect, a bidirectional discharge type pump that discharges oil by rotation in either the forward or reverse direction is used as the hydraulic pump for braking, and the winch drum is wound up. -The structure is such that the discharge oil of the brake hydraulic pump is supplied to the heat generating portion of the hydraulic brake during both lowering rotations.

According to a seventh aspect of the present invention, in the configuration of the fifth or sixth aspect, the cooling oil is supplied in parallel with the brake hydraulic pump so that the cooling oil can be supplied to the heat generating portion of the hydraulic brake even when the winch drum stops rotating. A cooling hydraulic pump is provided.

According to the above configuration, at the time of the free fall operation, the discharge oil of the brake hydraulic pump driven by the winch drum is applied to the drive unit of the hydraulic brake, and a braking force acts on the winch drum.

Thus, the rotation speed (free fall speed) of the winch drum is regulated. For this reason, the safety of the free fall operation is ensured, and the operation burden on the operator is reduced.

In addition, since the pump discharge oil amount changes in proportion to the drum rotation speed and the pump discharge line pressure (braking force) changes, the original free fall function is reliably maintained regardless of the magnitude of the load. Therefore, there is no possibility that free fall cannot be performed when the load is small.

According to the method of the second aspect and the configuration of the fifth aspect, the discharge oil of the brake hydraulic pump is supplied as cooling oil to the brake heat generating portion in parallel with the hydraulic brake, so that a dedicated cooling pump is not required. Become.

In addition, as described above, the pump discharge oil amount changes in proportion to the drum rotation speed, and the cooling oil amount increases as the drum rotation speed increases and the calorific value increases. Therefore, the cooling efficiency is further improved.

In the prior art shown in FIG. 5, it is necessary to use a large-capacity cooling pump 21 in order to secure a sufficient amount of cooling oil even at a low idling of the engine. As described above, since the cooling oil amount corresponding to the drum rotation speed, that is, the heat generation amount is secured, the pump capacity can be reduced.

On the other hand, according to the configuration of claim 4, since the discharge pipeline pressure (braking force) of the brake hydraulic pump is variable, the braking action is selected according to the amount of suspended load, work content, operator preference, and the like. be able to.

According to the sixth aspect of the present invention, since a bidirectional discharge pump of a hydraulic motor type is used as the hydraulic pump for the brake, the cooling oil is supplied to the brake heat generating part not only at the time of free fall but also at the time of hoisting. You. For this reason,
The cooling performance can be enhanced by being able to cool the brake heating part, which has become hot during free fall, even during hoisting.

Furthermore, according to the structure of claim 7, since the cooling operation is performed even when the rotation of the winch drum is stopped, the structure is suitable for a winch in which brake heat is intense. In this case, the cooling hydraulic pump requires a smaller capacity than the conventional cooling hydraulic pump.

[0045]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings.

First Embodiment (Refer to FIG. 1) In this embodiment, the same portions as those of the prior art shown in FIG. 5 are denoted by the same reference numerals, and the description thereof will not be repeated.

A ring gear 21 is provided on the outer periphery of the flange of the winch drum 1, and a hydraulic pump for braking (hereinafter referred to as a brake pump) 24 is connected to an output shaft of a spur gear 22 which rotates by meshing with the ring gear 21 via a one-way clutch 23. Are connected.

As a result, the brake pump 24 is driven to rotate by the winch drum 1 during the lowering rotation (free fall and power lowering) of the winch drum 1.

The discharge pipe 25 of the brake pump 24 is branched and connected to the extension pipe 14 of the cylinder 11, and a shuttle valve 26 is provided at the branch connection.

The cooling pipe 2 is connected to the pump discharge pipe 25.
7 is branched and connected, and the tip of the cooling pipe line 27 is connected to the heat generating portion of the hydraulic brake 12.

A fixed throttle 28 is provided in the cooling pipe 27 as pressure generating means. The pressure generated at the entrance of the fixed throttle 28 is the pressure of the pump discharge pipe 25, that is, the pressure of the hydraulic brake 12.

The operation of this device will be described.

During the free fall operation, as described above, the electromagnetic switching valve 18 is switched to the free fall position b by operating the switch 20, and the reduction side oil chamber 11b of the cylinder 11 is pressurized, so that the piston 10 Move away from

As a result, the hydraulic brake 12 is turned off, and in this state, the winch drum 1 rotates downward by the amount of the suspended load, and the free fall operation is performed.

During the free fall operation, the brake pump 24 is driven by the winch drum 1, and the discharged oil is supplied via the shuttle valve 26 to the extension-side oil chamber 11 of the cylinder 10.
a when the pressure in the expansion-side oil chamber 11a becomes higher than the pressure in the reduction-side oil chamber 11b.
Is pressed against the multi-plate clutch 9.

As a result, the carrier shaft 8 is braked, and a braking force determined by the opening area of the fixed stop 28 acts on the winch drum 1.

Thus, the rotation speed of the winch drum 1
That is, since the free fall speed is regulated to a certain value or less, there is no possibility that the suspended load falls freely without regulation, and safety during free fall operation is ensured.

If the operator operates the brake pedal 15 during the free fall operation, a pressure corresponding to the operation amount is applied to the cylinder extension side oil chamber 11a, so that the speed can be adjusted within the above-mentioned regulated speed. .

On the other hand, the oil discharged from the brake pump 24 is supplied as cooling oil to the brake heat generating portion through the cooling pipe 27 in parallel with the cylinder 11. Thus, during the free fall operation, the brake heat generating portion is cooled, and the brake performance is maintained.

In this case, the rotation speed of the brake pump 24 is proportional to the rotation speed of the winch drum 1, and the amount of cooling oil increases as the drum rotation speed increases and the amount of generated heat increases, so that the cooling efficiency is improved. .

Further, since the cooling oil amount corresponding to the heat generation amount is secured, the capacity of the brake pump 24 can be small.

The brake pump 24 is also driven when the power is lowered. At this time, the electromagnetic switching valve 18 is set to the normal operation position a, and the pressure does not rise in the reduction-side oil chamber 11b of the cylinder 11, but originally. Since the piston 10 is pressed against the multi-plate clutch 9 by the force of the spring 13, the operation does not change even when oil is supplied from the brake pump 24.

During hoisting, since the brake pump 24 is separated from the winch drum 1 by the action of the one-way clutch 23, no oil discharging action is performed.

Incidentally, a variable diaphragm may be used instead of the fixed diaphragm 28. By doing so, the regulation speed can be made variable in accordance with the amount of suspended load, work content, operator preference, and the like.

A switching valve operated by an operator may be used in place of the variable throttle, and the regulation speed may be arbitrarily set by adjusting the stroke of the switching valve.

Second Embodiment (See FIG. 2) In the following embodiment, only the differences from the first embodiment will be described.

In the second embodiment, as the brake pump 24 driven by the winch drum 1, a two-way discharge pump of a hydraulic motor type that discharges oil by rotation in either the forward or reverse direction is used as shown in the figure. I have.

In this case, the one-way clutch 23 is omitted, and the brake pump 24 is directly connected to the spur gear 22.

Further, on both sides of the brake pump 24, discharge pipes 25a and 25b are provided.
a and 25b are connected to the shuttle valve 26 or the tank T via a check valve block 29 in which four check valves are combined.

According to this configuration, the brake pump 24
However, since the pump discharge oil is supplied to the brake heat generating portion by being driven not only at the time of the lowering rotation of the winch drum 1 but also at the time of the hoisting rotation, the temperature of the brake heat generating portion which has become high during the free fall can be cooled even at the time of hoisting. , Cooling performance is enhanced.

At the time of hoisting, since the electromagnetic switching valve 18 is in the normal operation position a and the piston 10 is originally pressed against the multi-plate clutch 9, even if the discharge oil of the brake pump 24 is further supplied, the operation is continued. Has no effect.

Third Embodiment (see FIG. 3) In this embodiment, a cooling pump 30 driven by an engine (not shown) is provided separately from the brake pump 24, and a discharge line 31 of the cooling pump 30 is provided. The cooling pipe 27 is branched and connected.

A check valve 32 regulates the flow direction of the oil discharged from the pump 30 to the side of the brake heat generating portion.

According to this configuration, the oil discharged from the cooling pump 30 is supplied to the brake pump 2 when the winch drum 1 rotates.
4 and is supplied to the brake heat generating portion when the rotation of the drum is stopped.

That is, even when the drum is stopped, the cooling oil is supplied to the brake heat generating portion to perform the cooling operation, so that it is suitable for a winch in which the brake heat is intense.

In this case, the capacity of the cooling pump 30 is smaller than that of the conventional cooling hydraulic pump.

Fourth Embodiment (See FIG. 4) In each of the first to third embodiments, the structure in which the secondary pressure of the pressure reducing valve (brake valve) 16 is supplied to the cylinder 11 by operating the brake pedal 15 is adopted. By operating the brake pedal 15 as in the fourth embodiment, the master cylinder 3
A well-known configuration in which the static oil pressure from 3 is sent to the cylinder 11 may be adopted. 34 is a reservoir of the master cylinder 33.

With this configuration, it is possible to obtain basically the same functions and effects as those of the other embodiments.

In each embodiment, a relief valve 35 as a safety valve for regulating the maximum pressure may be connected to the discharge line 25 of the brake pump 24 as shown in FIG.

In each of the above embodiments, the power transmission / shutoff function and the braking action at the time of free fall are obtained by fixing / releasing the carrier shaft 8 of the planetary gear mechanism 3, but the present invention is not limited thereto. The present invention can also be applied to a case in which a clutch and a brake are provided independently of each other and are separately controlled as another known configuration.

In each of the above-described embodiments, a clutch is provided between the brake pump 24 and the spur gear 22, and during free fall, the brake pump 24 is separated from the winch drum 1 as required to regulate the speed. You may comprise so that complete free fall operation which does not have an effect can be performed.

[0082]

As described above, according to the present invention, the brake hydraulic pump is driven by the winch drum during the free fall operation, and the discharge oil of the pump is applied to the hydraulic brake driving section to apply the braking force to the winch drum. By controlling the free fall speed, the free fall speed is regulated, so that the free fall speed can be regulated while securing the original free fall function, and work safety can be achieved.

According to the second and fifth aspects of the present invention, since the discharge oil of the brake hydraulic pump is supplied as cooling oil to the brake heat generating portion in parallel with the hydraulic brake, a dedicated cooling pump is not required.

In addition, as described above, the pump discharge oil amount changes in proportion to the drum rotation speed, and the cooling oil amount increases as the drum rotation speed increases and the heat generation amount increases. Therefore, the cooling efficiency is further improved.

Further, since the amount of cooling oil corresponding to the drum rotation speed, that is, the amount of heat generated in the brake heat generating portion is secured, the pump capacity can be reduced.

On the other hand, according to the fourth aspect of the present invention, since the discharge pipeline pressure (braking force) of the hydraulic pump for braking is variable, the braking action according to the amount of suspended load, work content, operator preference, etc. is selected. be able to.

According to the sixth aspect of the present invention, since a bidirectional discharge pump of a hydraulic motor type is used as the hydraulic pump for braking, cooling oil is supplied to the brake heat generating part not only at the time of free fall but also at the time of hoisting. You. For this reason,
The cooling performance can be enhanced by being able to cool the brake heating part, which has become hot during free fall, even during hoisting.

Further, according to the invention of claim 7, since the cooling action is performed even when the rotation of the winch drum is stopped, it is suitable for a winch in which the brake heat is intense. In this case, the cooling hydraulic pump requires a smaller capacity than the conventional cooling hydraulic pump.

[Brief description of the drawings]

FIG. 1 is a hydraulic circuit diagram showing a first embodiment of the present invention.

FIG. 2 is a hydraulic circuit diagram showing a second embodiment of the present invention.

FIG. 3 is a hydraulic circuit diagram showing a third embodiment of the present invention.

FIG. 4 is a hydraulic circuit diagram showing a fourth embodiment of the present invention.

FIG. 5 is a hydraulic circuit diagram showing a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Winch drum 2 Hydraulic motor for driving the same drum 12 Hydraulic brake 9 Multi-plate clutch constituting a hydraulic brake 10 Same piston 11 Same cylinder 13 Same spring 18 Electromagnetic switching valve constituting switching means 20 Same switch 24 Hydraulic pump for brake 21, 22 Gear for connecting the pump and winch drum 23 One-way clutch 25 Discharge pipeline of hydraulic pump for brake 27 Cooling pipeline 28 Fixed throttle as pressure generating means 30 Cooling hydraulic pump

Claims (7)

[Claims] 1. A hydraulic brake is provided on a winch drum rotationally driven by a hydraulic motor, and an operation mode is set between a normal hoisting / lowering operation in which the winch drum is rotated by the hydraulic motor and a winch drum by a load. In a hydraulic winch provided with a switching means for switching between a free fall operation for lowering and lowering, a brake hydraulic pump rotationally driven by the winch drum is provided, and a pressure from the brake hydraulic pump is provided during the free fall operation. A method for controlling a hydraulic winch, wherein a maximum rotation speed of a winch drum is limited by applying oil to a driving portion of the hydraulic brake in a brake operating direction. 2. The hydraulic winch control method according to claim 1, wherein the pressure oil from the brake hydraulic pump is supplied as cooling oil to the heat generating portion of the hydraulic brake in parallel with the drive portion of the hydraulic brake. Hydraulic winch control method. 3. A winch drum, which is rotatably driven by a hydraulic motor, is provided with a hydraulic brake. The operating mode is set to a normal hoisting / lowering operation in which the winch drum is rotated by the hydraulic motor, and the winch drum is driven by a load. In a hydraulic winch provided with a switching means for switching between a free fall operation in which a lowering rotation is performed, a brake hydraulic pump is provided at least in a state of being rotationally driven by the winch drum during the free fall operation. A pressure generating means is provided in the discharge line of the hydraulic pump so that the hydraulic pressure generated in the discharge line of the hydraulic pump is applied to the hydraulic brake in the brake operating direction, and the line is connected to the drive unit of the hydraulic brake. A control device for a hydraulic winch. 4. The control device for a hydraulic winch according to claim 3, wherein a valve whose set pressure is variable is used as the pressure generating means. 5. A pump discharge line and a heat generating portion of a hydraulic brake so that a discharge oil of a hydraulic pump for a brake can be supplied as a cooling oil to a heat generating portion of the hydraulic brake in parallel with a driving portion of the hydraulic brake. 5. The control device for a hydraulic winch according to claim 3, wherein a cooling pipeline is connected between the control devices. 6. A bi-directional discharge type pump which discharges oil by rotation in both forward and reverse directions is used as a hydraulic pump for braking, and the hydraulic pump for braking is used when the winch drum rotates both up and down. The hydraulic winch control device according to claim 5, wherein the discharge oil is configured to be supplied to a heat generating portion of the hydraulic brake. 7. A cooling hydraulic pump is provided in parallel with the brake hydraulic pump so that cooling oil can be supplied to the heat generating portion of the hydraulic brake even when the rotation of the winch drum is stopped. Item 7. The control device for a hydraulic winch according to item 5 or 6.