JP2805291B2 - Crane lifting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hoisting apparatus for a crane that winds or unwinds a wire rope wound around a winding drum to lift and lower a load hung on a crane.

[0002]

2. Description of the Related Art Conventionally, as a hoisting apparatus for hoisting a crane of this type, there is, for example, a first conventional structure shown in FIG. The rotation torque output from the prime mover 1 is transmitted to a torque converter 3 via a wet multi-plate clutch 2.
The torque converter 3 transmits the transmitted rotational torque using a fluid, and transmits the transmitted rotational torque to the speed reducer 4. The speed reducer 4 reduces the rotation speed of the shaft by the transmitted rotation torque and transmits the reduced rotation speed to the winch winding drum 5. The winch winding drum 5 is rotationally driven by the transmitted rotational torque. When the winch winding drum 5 is driven to rotate, the hoisting wire rope 6 is wound around the winch winding drum 5, and the suspended load 7 hung on a jib of a crane (not shown) is hoisted. When lowering the suspended load 7 with a light load, the wet multi-plate clutch 2 is released, and the transmission of motive power from the prime mover 1 to the torque converter 3 is cut off. Therefore, the rotation torque is not transmitted to the winch winding drum 5, and the winch winding drum 5 rotates in the reverse direction by the weight of the suspended load 7. That is, the hoisting wire rope 6 is unwound from the winch winding drum 5 by the weight of the suspended load 7, and the suspended load 7 is lowered.

[0003] There is also a conventional hoisting and hoisting device for a second crane having the structure shown in FIG. Note that FIG.
The same parts as those in FIG.
In this hoisting hoisting apparatus, a dry clutch 8 is provided between the speed reducer 4 and the winch winding drum 5, and the other configuration is the same as the above-described apparatus shown in FIG. The hoisting of the suspended load 7 is performed by transmitting the rotational torque from the speed reducer 4 to the winch winding drum 5 through the dry clutch 8 and winding the hoisting wire rope 6 in the same manner as described above. Further, when lowering the lightly loaded suspended load 7, the winch winding drum 5 is separated from the power system by the dry clutch 8 without releasing the wet multi-plate clutch 2. Then, while the winch winding cylinder 5 is braked by the brake 9, the hoisting wire rope 6 is paid out by the weight of the suspended load 7, and the suspended load 7 descends.

[0004] There is also a third conventional hoisting apparatus for hoisting a crane having the structure shown in FIG. Note that FIG.
The same parts as those described above are denoted by the same reference numerals and description thereof will be omitted.
In this device, a forward / reverse switching transmission 10 is provided between the torque converter 3 and the speed reducer 4, and the other configuration is the same as that of the device shown in FIG. When the direction of the rotational torque output from the torque converter 3 is switched from the forward rotation direction to the reverse rotation direction by the forward / reverse switching mission 10, the winch winding drum 5 is rotationally driven in the reverse direction. When the light load suspended load 7 is to be unwound, the forward / reverse switching transmission 10 is operated to forcibly rotate the winch winding drum 5 in the reverse direction. When rotated in the opposite direction, the hoisting wire rope 6 is unwound from the winch winding drum 5, and the suspended load 7 is unwound.

[0005]

However, in the above-described conventional first hoist hoisting apparatus for a crane shown in FIG. 3, the winch winding drum 5 is always receiving a rotational torque in the hoisting direction. That is, even when the wet multi-plate clutch 2 is released and the input of the torque converter 3 is restricted when the suspended load 7 is lowered, the rotation of the winch drum 5 in the winding direction is caused by some viscous resistance of the working fluid. The torque does not go to zero. For this reason, depending on the above-mentioned conventional first suspended load hoisting device, there is a case where the lightly suspended load 7 cannot be lowered. In some cases, the lightly-loaded suspended load 7 may be hoisted.

In the second conventional hoisting hoist of the crane shown in FIG. 4, when the hoisting load 7 with a light load is lowered, the winch winding drum 5 is separated from the power system by the dry clutch 8. This does not cause such a problem. However, when lowering the suspended load 7 with a light load from a high lift, the winch winding cylinder 5 is braked by the brake 9 for a long time. For this reason, the brake 9 generates heat due to friction, causing a fade phenomenon, and the effectiveness of the brake 9 is reduced. When the effectiveness of the brake 9 decreases, the winch
Braking becomes difficult, and the danger of falling of the suspended load 7 occurs.
The speed at which the hoisting wire rope 6 is fed out from the winch winding drum 5 depends on the braking force of the brake 9 on the winch winding drum 5. It is difficult to delicately control this braking force. Therefore, it is difficult to finely operate the lowering of the suspended load 7 by the above-mentioned conventional second suspended load hoisting device, and it is not possible to perform the slow speed control. Therefore, it is difficult to position the suspended load 7 with high accuracy.

In the third conventional hoisting apparatus for hoisting a crane shown in FIG. 5, when the hoisting load 7 with a light load is lowered, the forward / reverse switching transmission 10 forcibly reverses the rotational torque. Is required. Therefore, according to the third conventional hoisting hoist described above, the time required for the switching operation of the forward / reverse switching transmission 10 during the lowering operation is troublesome, and the lowering operation cannot be performed quickly. Further, once the direction of the rotational torque is reversed by the forward / reverse switching transmission 10, the rotational torque cannot be applied in the hoisting direction of the suspended load 7. For this reason, when lowering the suspended load 7, similarly to the above-mentioned second conventional hoisting device, the hoisting wire rope 7 is unwound while the winch winding drum 5 is also braked by the brake 9. Therefore, when the head is lowered at a high head, the brake 9 may generate heat and cause a fade phenomenon as in the second conventional configuration, and there is a danger that the suspended load 7 may fall.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and has a motor that outputs a driving force as a rotational torque, and a clutch that slides the transmission of the rotational torque output from the motor. Hoist hoisting of a crane including a torque converter that transmits a rotational torque transmitted through the clutch using a fluid, and a winding drum that is rotationally driven by the rotational torque output from the torque converter The apparatus is characterized in that a torque generating mechanism for generating a rotational torque in a direction opposite to the rotational torque transmitted by the torque converter is provided.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment in which a crane lifting device according to the present invention is applied to a crane working boat will be described. FIG. 1 is a block diagram showing a configuration of a crane lifting device according to the present embodiment.

The prime mover 11 outputs the prime mover as a rotational torque. The transmission of the rotational torque output from the prime mover 11 is slid by the wet multi-plate clutch 12. That is, by changing the degree of clutch engagement, the rotational torque transmitted to the driven-side shaft of the wet-type multi-plate clutch 12 is adjusted. The rotational torque transmitted via the wet multi-plate clutch 12 is transmitted in the torque converter 13 using hydraulic fluid as a fluid. That is, the rotational torque transmitted from the wet multi-plate clutch 12 is given to the input shaft of the torque converter 13 and rotates the pump blades in the torque converter 13 connected to the input shaft. The kinetic energy is given to the hydraulic oil by the rotation of the pump blade, and the turbine blade connected to the output shaft of the torque converter 13 is rotated. By the rotation of this turbine blade,
The rotational torque transmitted from the wet multi-plate clutch 12 is transmitted to the speed reducer 14 as converted power. The speed reducer 14 reduces the rotation speed of the shaft that rotates by the transmitted power at a predetermined ratio. The winch winding drum 15 is rotationally driven by the reduced power. A winding wire rope 16 is wound around the winch winding drum 15, and the winding wire rope 1
A suspended load 17 is suspended from 6.

The reduction gear 14 has a torque generating mechanism 18.
The torque generating mechanism 18 always generates a rotational torque in a direction opposite to the rotational torque transmitted by the torque converter 13. That is, the torque converter 13 transmits a forward rotation torque that rotates the winch winding cylinder 15 forward and winds the suspended load 17. This forward rotation torque rotates the shaft in the direction indicated by the solid line in FIG. The torque generating mechanism 18 generates a reverse rotation torque in a direction opposite to the normal rotation torque. This reverse rotation torque drives the shaft to rotate in the direction indicated by the dashed arrow in the figure, and urges the drum shaft in the direction in which the winch winding drum 15 is reversed and the suspended load 17 is lowered. Therefore, when there is no suspended load 17, if the coupling of the wet type multi-plate clutch 12 is weakened, the torque generated by the torque generating mechanism 18 becomes a load in the lowering direction with respect to the torque converter 13. That is, when the connection of the wet type multi-plate clutch 12 is weakened without the suspended load 17, the output shaft of the torque converter 13 is reversed, and the winch winding drum 15 rotates in the lowering direction.

Such a torque generating mechanism 18 can be easily realized by using a hydraulic motor or an electric motor so that the rotation torque generated by these motors forms the above-described reverse rotation torque. The torque generating mechanism 18 having this configuration may be mounted anywhere as long as it is located after the output shaft of the torque converter 13. Further, a torque generating mechanism 18 that mechanically transmits the reverse rotation torque to the input shaft of the torque converter 13 can be configured. In this embodiment, any of these torque generating mechanisms 1
8 may be used.

In such a configuration, the operation of hoisting the suspended load 17 is performed in the same manner as in the above-described suspended load hoisting apparatus according to the first prior art. That is, the forward rotation torque output from the prime mover 11 is transmitted to the torque converter 13 via the wet multi-plate clutch 12, and the power reduced by the speed reducer 14 is transmitted to the winch winding drum 15. With this transmission torque, the winch winding drum 15 is driven to rotate in the normal rotation direction, the winding wire rope 16 is wound, and the suspended load 17 is wound.

On the other hand, at the time of the operation of lowering the suspended load 17, the reverse rotation torque generated by the torque generating mechanism 18 is increased. Alternatively, when the magnitude of the reverse rotation torque generated by the torque generating mechanism 18 is fixed, the wet multi-plate clutch 12
Is weakened, and the forward rotation torque transmitted to the torque converter 13 is reduced. When the reverse rotation torque generated in the torque generation mechanism 18 overcomes the normal rotation torque due to the viscous resistance of the working oil in the torque converter 13, or the normal rotation torque transmitted by the wet multi-plate clutch 12 is generated in the torque generation mechanism 18. When the torque is weaker than the reverse rotation torque, the torque converter 13 rotates in the reverse direction. Therefore, when the reverse load torque is relatively increased with respect to the forward rotation torque when the light load suspended load 17 is unwound, the reverse rotation torque is transmitted to the winch winding drum 15 and the winch winding drum 15 is wound. It is driven in reverse rotation in the down direction. Therefore, according to the crane hoisting device of the present embodiment, the load 1
7 is reliably lowered, so that the suspended load 17 is not lowered or rolled up due to the fluid resistance of the hydraulic oil of the torque converter 13 unlike the related art.

The lowering operation is performed by the torque generating mechanism 18.
This is actively performed by adjusting the magnitude of the reverse rotation torque generated in the above, or by adjusting the magnitude of the forward rotation torque transmitted by the wet multi-plate clutch 12, and applies a brake to the winch winding cylinder 15 to passively lower the winch. Different from operation. For this reason, there is no fear that the brake generates heat and causes a fade phenomenon when the head is lowered at a high head, and the conventional danger of the suspended load 17 falling is eliminated.

The lowering speed of the suspended load 17 is adjusted by changing the magnitude of the reverse torque generated by the torque generating mechanism 18 or by changing the degree of coupling of the wet multi-plate clutch 12. The magnitude of the reverse torque and the degree of clutch engagement can be easily finely adjusted by the torque generating mechanism 18 and the wet multi-plate clutch 12, respectively.
Fine operation of lowering is possible. Therefore, according to the present embodiment, there is provided a crane lifting device capable of positioning the lifting load 17 with high accuracy.

Further, the lowering operation is performed by the torque generating mechanism 1.
8, the magnitude of the reverse rotation torque or the degree of coupling in the wet-type multi-plate clutch 12 can be adjusted only by adjusting the reverse rotation torque to a level that overcomes the normal rotation torque due to the viscous torque in the torque converter 13. In other words, the operation of lowering the suspended load 17 with a light load can be performed simply and quickly as compared with the conventional operation of lowering the load by switching the forward / reverse switchover transmission or intermittently connecting the dry clutch.

That is, in the second and third prior arts described above, since the braking cannot be applied by the wet multi-plate clutch when the light load is lowered, the load on the brake increases, and the danger is increased. . However, according to the present embodiment, a winch mechanism that can safely and quickly lower the lightly-loaded load 17 without relying on a mechanical brake while using the wet-type multi-plate clutch 12, that is, the lifting load of the crane. The device is realized.

When the above-described torque generating mechanism 18 generates the same forward rotation torque as the forward rotation torque transmitted by the torque converter 13, the prime mover 11 and the torque converter 1
3 can be used as emergency power in case of failure.

Further, in the hoisting hoisting apparatus having the structure shown in FIG.
Of the output shaft, the power loss occurs. This loss can be prevented by providing the clutch 19 shown in FIG. 2 to the output of the torque generating mechanism 18 of the hoisting hoist according to this embodiment. In this figure, the same parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. That is, by disconnecting the coupling between the torque generating mechanism 18 and the power system by the clutch 19, the torque generating mechanism 18 of the torque converter 13 is separated.
The load due to is eliminated. Therefore, by operating the clutch 19 when lifting a heavy object, the power generated by the prime mover 11 can be used without waste.

Even without providing such a clutch 19, it is possible to prevent power loss even if the torque generated by the torque generating mechanism 18 is adjusted so that the reverse rotation torque approaches zero.

In the above embodiment, the case where the present invention is applied to a crane working boat has been described. However, the present invention is not limited to this, and may be applied to other cranes such as a crawler crane. It is. In this case, the same effect as in the above embodiment can be obtained.

[0023]

As described above, according to the present invention, when the reverse rotation torque generated in the torque generating mechanism relatively overcomes the normal rotation torque due to the viscous resistance of the fluid in the torque converter, the torque converter reverses. Rotate. Therefore, when lowering a lightly suspended load, if the reverse rotation torque is made relatively large with respect to the normal rotation torque, a rotation torque in the opposite direction is transmitted to the winding drum, and the winding drum is rotated in the lowering direction. It is driven to rotate. For this reason, the suspended load can be reliably lowered. Further, since the lowering operation is performed without applying the brake, there is no fear that the brake will be faded at the time of lowering the head at a high head, and the conventional danger of falling of the suspended load is eliminated. Further, the lowering of the suspended load is finely operated by finely adjusting the magnitude of the reverse rotation torque generated by the torque generating mechanism or the coupling degree of the clutch transmitting the forward rotation torque, and the suspended load is positioned with high precision. You. Further, such a lowering operation can be performed quickly and smoothly.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a crane lifting device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an improved configuration of the crane lifting device according to the embodiment shown in FIG. 1;

FIG. 3 is a block diagram illustrating a conventional first crane hoisting device.

FIG. 4 is a block diagram showing a second conventional hoisting and hoisting device for a crane.

FIG. 5 is a block diagram showing a third conventional hoisting apparatus for lifting a crane.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Prime motor 12 ... Wet multi-plate clutch 13 ... Torque converter 14 ... Reduction gear 15 ... Winch winding cylinder 16 ... Hoisting wire rope 17 ... Suspended load 18 ... Torque generator 19 ... Clutch

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B66D 1/24 B66D 1/14 B66D 1/44

Claims (1)

(57) [Claims] A motor that outputs a driving force as a rotational torque, a clutch that slides the transmission of the rotational torque output from the motor, and a torque converter that transmits the rotational torque transmitted through the clutch using a fluid. A hoisting device for a crane, comprising: a winding drum that is rotationally driven by a rotational torque output from the torque converter; and a torque that generates a rotational torque in a direction opposite to the rotational torque transmitted by the torque converter. An apparatus for hoisting a suspended load of a crane, comprising a generating mechanism.