JP2002080190A - Power transmitting device for driving rotary drum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmitting device for driving a small-sized rotary drum having a structure which can hoist up and down a slung load by a fine amount additionally to improve responsiveness in the case of hoisting up the slung load after it is rapidly lowered down. SOLUTION: In this power transmitting device for driving a rotary drum, provided with a first slipping clutch in an input shaft of a torque converter and a reversing gear mechanism in an output shaft of the torque converter to switch the direction of rotation of the rotary drum mounted in this output shaft by a forward and reverse rotation switching clutch, the forward and reverse rotation switching clutches are constituted respectively by a second slipping clutch and a wet multi-disc hydraulic clutch, a rotational speed of an output shaft of the reversing gear mechanism is controlled by combination of selective connection of the first and the second slipping clutch.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission device for driving a rotary drum such as a grab dredger and a crane, and more particularly to a torque converter with a slipping clutch for controlling the rotation speed of a rotary drum, a reverse gear mechanism, and the like. The present invention relates to a power transmission device provided with:

[0002]

2. Description of the Related Art Generally, the output torque characteristic of a torque converter is such that when the rotation speed of an impeller wheel is constant and the rotation directions of the impeller wheel and the turbine wheel are the same, the turbine torque decreases as the rotation speed of the turbine wheel increases. That is, if the rotation speed of the turbine wheel decreases, the turbine torque increases. When the rotation directions of the impeller wheel and the turbine wheel are opposite, the turbine torque increases as the rotation speed of the turbine wheel increases, and the turbine torque decreases as the rotation speed of the turbine wheel decreases. Furthermore, at the same turbine wheel rotation speed, regardless of the rotation direction of the turbine wheel, the turbine torque increases as the rotation speed of the impeller wheel increases, and the turbine torque decreases as the rotation speed of the impeller wheel decreases. Have.

In a conventional hoisting work machine such as a grab dredger or a crane, a torque converter with a slipping clutch utilizing the output torque characteristics of the torque converter as described above is used for a power transmission device for driving a drum. . For example, there is an apparatus described in JP-A-1-83728 for raising and lowering a bucket of a dredger. In this device, the lifting and lowering of the bucket is performed by adjusting the clutch operating oil pressure that presses the clutch plate of the slipping clutch to thereby control the degree of clutch engagement (hereinafter referred to as “slip ratio”).
That. ) Is controlled. That is, if the clutch operating oil pressure is increased while the engine speed is set to a predetermined value, the slip ratio of the clutch decreases and the output rotation speed of the clutch, that is, the rotation speed of the impeller wheel increases. Therefore, when the turbine torque of the torque converter increases and becomes larger than the load torque, the input / output shaft of the torque converter rotates in the same direction and the bucket rises.

Conversely, when the slip rate is increased by decreasing the clutch operating oil pressure and the output rotational speed of the clutch is reduced, the turbine torque decreases to become smaller than the load torque turned from the bucket side, and the turbine The bucket starts to reverse, and the bucket descends while a brake torque (turbine brake) corresponding to the rotation speed of the turbine wheel is applied. Further, by setting the intermediate hydraulic pressure at which the rising and falling are switched, the turbine torque and the load torque are balanced, and the bucket can be kept stationary.

As described above, the torque converter with a slipping clutch can change the rotation speed of the impeller wheel only by adjusting the clutch operating oil pressure without changing the rotation speed of the engine. It is widely used for hoisting work machines such as dredgers and cranes because it can control the lowering speed and the turbine brake works at the time of lowering. However, in the torque converter with a slipping clutch, the turbine wheel is turned by the weight of the suspended load from the suspended load side at the time of lowering as described above. Due to the strong influence of the inertia of the drum and the reduction gear train arranged between them, there was a difficulty in responsiveness until the vehicle began to descend. As a solution to this disadvantage, there has been provided a power transmission device in which a reverse gear mechanism is provided on an output shaft of the torque converter with a slipping clutch.

FIG. 5 shows a conventional power transmission device 100 for driving a rotary drum provided with a reverse gear mechanism. A torque converter 102 with a slipping clutch 101 and an output shaft 102 of the torque converter 102 are shown.
The main part is constituted by the reversing gear mechanism 103 provided in B. The output shaft of the engine is a slipping clutch 10
The output shaft 103B of the reversing gear mechanism 103 is connected to a rotating drum via a reduction gear, and a wire for lifting and suspending a load is wound around the rotating drum. I have. The drive shaft 103DA of the reverse gear mechanism 103 is provided with a reverse clutch RC, and the intermediate shaft 103MA is provided with a forward clutch NC.
The drive shaft 103DA has a drive gear 10 formed integrally with an outer ring which is a drive side member of the reverse rotation clutch RC.
4 is fixed, is formed integrally with the outer ring of the forward rotation clutch NC, and meshes with the driven gear 105 fixed to the intermediate shaft 103MA. The forward rotation clutch NC
An inner ring 109 fixed to the casing and an outer ring formed integrally with the drive gear 104 serving as a member to be braked are connected to the end of the drive shaft 103DA facing the drive shaft 103DA by operating hydraulic pressure to control the drive shaft 103DA. A hydraulic multi-disc brake OB for applying power is provided. In addition, the drive shaft 103DA and the intermediate shaft 103MA rotatably support a reverse rotation pinion 106 and a normal rotation pinion 107 via bearings, and each pinion meshes with an output gear 108 fixed to the output shaft 103B. By connecting the reverse rotation clutch RC, the reverse rotation pinion 106 and the driving gear 104 rotate integrally, and by connecting the normal rotation clutch NC, the normal rotation pinion 107 and the driven gear 10 are rotated.
5 rotates together. Therefore, by switching these clutches, the rotation direction of the output shaft 103B is reversed.

The hoisting speed and the hoisting speed of the load in the conventional power transmitting device 100 for driving a rotary drum configured as described above are controlled as follows. (1) Control of load hoisting speed Regardless of the weight of the suspended load (load), the forward rotation clutch N
C is engaged and the operating oil pressure (pressing force) of the slipping clutch 101 in a state where the reverse clutch RC is disconnected.
Is controlled by controlling the slip rate of the slipping clutch 101 and the output rotation speed of the slipping clutch 101, that is, the input rotation speed of the torque converter 102, is controlled.
02, the rotation speed of the impeller wheel IW is controlled, and the winding speed is arbitrarily controlled. Here, as a method of controlling the operating oil pressure of the slipping clutch 101, known means conventionally used, such as control by an electric signal using a proportional solenoid valve, is used.

(2) Control of load lowering speed Control of the lowering speed is selectively used according to the weight of the suspended load (load) as follows. In the case of a heavy load, the forward clutch N
C, the reverse rotation clutch RC is disengaged, and the slip speed of the slipping clutch 101 is controlled to change the rotation speed of the impeller wheel IW.
The descending speed is controlled by adjusting the reverse rotation speed of the turbine wheel TW. In addition, impeller foil IW
When the rotational speed of the turbine wheel TW is reduced to a certain speed, the braking torque (turbine torque) of the reversing turbine wheel TW becomes constant, and the descent speed becomes constant. 1
02 by discharging the oil. When the load is light, the impeller wheel IW and the turbine wheel TW are turned down in the same direction in order to speed up the response. That is, the reverse clutch RC is connected, the normal clutch NC is disconnected, and the drum is rotated in the direction opposite to the direction in which the drum is wound by the torque of the engine to forcibly unwind the wire and unload the suspended load. The control of the descent speed at this time is performed by controlling the slip ratio of the slipping clutch 101, but the input side rotation speed of the slipping clutch 101, that is, the rotation speed of the engine also corresponds to the load torque under heavy load. It is necessary to set the rotation speed to a high value so that the hydraulic multi-disc brake OB is operated to apply an auxiliary load (brake load) to the output side of the torque converter 102, and the descent speed becomes too fast. Has been prevented.

[0009]

However, the conventional power transmission device 100 for driving a rotary drum has the following problems. (1) An independent hydraulic multi-disc brake OB is installed in order to improve the responsiveness of unwinding under a light load. For this reason, there is a disadvantage that the size of the gear box 100C provided with the reversing gear mechanism 103 in the longitudinal direction becomes large and the weight becomes large. (2) The input shaft 102A of the torque converter 102
The rotation speed of the impeller wheel IW of the torque converter 102 is controlled by controlling the slip ratio of the slipping clutch 101 disposed in the power transmission device 100, and the output of the power transmission device 100 via the kinetic energy of oil in the torque converter 102, that is, fluid. Since the rotation speed of the shaft 103B is controlled, even if the rotation speed of the impeller wheel IW changes, the rotation speed of the turbine wheel TW does not follow instantaneously, and it is difficult to perform a small amount of hoisting and lowering operations. (3) Further, when the suspended load is rapidly dropped, the oil in the torque converter 102 is discharged. Therefore, it is necessary to fill the oil in the torque converter 102 in a subsequent hoisting operation, during which the winding is started. Not responsive. As described above, in the conventional power transmission device 100, there is a problem in control responsiveness of hoisting and lowering under specific use conditions, and there is a disadvantage that the power transmitting device 100 itself becomes large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and a gear box containing a reversing gear mechanism is small and lightweight, capable of winding up and down a small amount of a suspended load, and It is another object of the present invention to provide a power transmission device for driving a rotary drum having a structure in which the winding response after rapid lowering is improved.

[0011]

According to a first aspect of the present invention, an input shaft of a torque converter includes a first slipping clutch, and an output shaft of the torque converter. Is a power transmission device for driving a rotating drum provided with a reversing gear mechanism for switching the rotation direction of a rotating drum attached to its output shaft by means of a forward switching clutch and a reverse switching clutch. A second slipping clutch, the reverse switching clutch is a wet multi-plate hydraulic clutch, and the reverse gear mechanism is combined with a combination of the first slipping clutch and the second slipping clutch. Is configured to control the rotation speed of the output shaft.

As described above, the reverse switching clutch is constituted by a wet multi-plate hydraulic clutch, and the forward switching clutch is constituted by a second slipping clutch, and the first slipping clutch and the second slipping clutch are formed. The following operations and effects can be obtained by combining the slipping clutch with the second slipping clutch so that the rotation speed of the output shaft of the reverse gear mechanism is arbitrarily controlled. (1) The responsiveness is improved without providing a separate brake load application mechanism for lowering the light load, the number of components of the reverse gear mechanism is reduced, and the entire power transmission device is reduced in weight and size. (2) When the suspended load is rapidly lowered, it is not necessary to discharge the oil in the torque converter, so that the subsequent hoisting response time is shortened. (3) The rotational speed of the drum is directly controlled by adjusting the slip ratio of the forward rotation switching clutch (second slipping clutch) of the reverse gear mechanism disposed on the output side of the torque converter without passing through the torque converter. Because of this, it is possible to instantaneously raise and lower a minute amount, which was difficult in the past.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a power transmission device for driving a rotary drum according to the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view showing an embodiment of a power transmission device for driving a rotary drum according to the present invention, and FIG. 2 is an explanatory diagram for explaining a structure of a reverse gear mechanism according to the present invention. FIG. 3 is an explanatory diagram of a control concept when operating a power transmission device for driving a rotary drum according to the present invention, and FIG.
1 is a schematic hydraulic system diagram of a power transmission device for driving a rotary drum according to the present invention.

First, an embodiment of a power transmission device for driving a rotary drum according to the present invention will be described with reference to FIGS. As shown in FIG. 1, a power transmission device 1 for driving a rotary drum according to the present invention includes a torque converter 3 in which a first slipping clutch 2 is connected to an input shaft 3A, and an output shaft 3B of the torque converter 3. And a reverse gear mechanism 4 for switching the rotation direction of a rotary drum connected to the output shaft OS via a speed reducer, and the first slipping clutch 2, the torque converter 3, and the reverse gear mechanism 4 The main part is constituted by the casing 5 which is housed inside and has the input shaft 2A of the first slipping clutch 2 and the output shaft OS of the reversing gear mechanism 4 protruding outside.

The first slipping clutch 2 is of a wet multi-plate hydraulic type rotatably supported by a casing 5 via a bearing, and is provided with a clutch hub S integral with the input shaft 2A.
A plurality of disc-shaped input clutch plates 2X spline-fitted to T, and disc-shaped spline-fitted clutch wheels CE integral with the output shaft 2B and alternately arranged with the input shaft clutch plates 2X. And a plurality of output shaft clutch plates 2W. These human output side clutch plates 2
X and 2W are coupled by applying pressure oil supplied from a hydraulic pump via a hydraulic control valve to an annular piston chamber CS and pressing a clutch piston CP, and friction surfaces of the input / output side clutch plates 2X and 2W. Is supplied with lubricating oil for cooling heat generated by slip. The slip ratio between the input and output clutch plates is controlled by changing the clutch operating oil pressure supplied to the piston chamber CS by the hydraulic control valve. That is, when the clutch operating oil pressure is reduced, the coupling force between the input and output shaft side clutches is weakened, and the rotational speed of the output shaft 2B is reduced. And the rotation speed of the output shaft 2B approaches the rotation speed of the input shaft 2A. When the clutch operating oil pressure is increased to a predetermined pressure or higher, the clutch slip is eliminated and a direct connection state is established, so that the rotation speed of the input shaft 2A and the rotation speed of the output shaft 2B become the same. Also, the control of the clutch operating oil pressure is, for example,
As shown in FIG. 4, it is controlled by an electric signal using a proportional solenoid valve 40. The second slipping clutch, which is a forward rotation clutch described later, has the same structure and function as the first slipping clutch.

The torque converter 3 is held in a casing 5, and the input shaft 3A is connected to the output shaft 2B of the first slipping clutch 2 and the output shaft 3B is connected to the drive shaft of the reverse gear mechanism 4 via a spline SP. Connected to DS. The torque converter 3 includes an impeller wheel IW, a turbine wheel TW, and an impeller wheel IW and a turbine wheel TW.
After converting the mechanical energy given to the impeller wheel IW into the velocity energy of fluid (oil), the turbine SR and the turbine wheel TW are housed in a sealed housing CH. The power is transmitted again from the impeller wheel IW to the turbine wheel TW by returning to the mechanical energy again.

Next, the reverse gear mechanism 4 will be described.
Hereinafter, the forward rotation switching clutch is referred to as a forward rotation clutch, and the reverse rotation switching clutch is referred to as a reverse rotation clutch. As shown in FIGS. 1 and 2, the reverse gear mechanism 4 meshes with a spline SP provided on the inner wall surface of the end portion of the output shaft 3B of the torque converter 3, and the drive gear DS1 and the reverse clutch DS
2 and a reverse pinion DS3 in this order, a drive shaft DS rotatably supported at both ends thereof, and the reverse pinion D
An output shaft OS having an output gear OS1 meshing with S3, rotatably supported at two points, and having one end protruding outside of the casing 5 with a mounting portion for mounting a rotary drum via a speed reducer. And a driven gear MS1, a forward rotation clutch MS2 and an output gear OS meshing with the drive gear DS1.
The main part is composed of an intermediate shaft MS rotatably supported at both ends by rotatably supporting both ends of a normal rotation pinion MS3 that meshes with the rotation pinion MS3. The drive shaft DS, the output shaft OS, and the intermediate shaft M
S are arranged in parallel with each other, and the output axis OS is arranged at a position in the horizontal direction with respect to the drive axis DS, and the intermediate axis MS is arranged at an obliquely lower position. The reverse gear mechanism 4 is housed in a room 5A of the casing 5.

Next, the operation of the power transmission device for driving the rotary drum composed of these components will be described with reference to FIGS. (1) The power of the engine is supplied to the first slipping clutch 2 in which the input / output side clutch plates 2X and 2W are pressed by the clutch operating oil pressure to set the slip ratio (degree of connection).
To the input shaft 2A. The input shaft 3A of the torque converter 3 is connected to the output shaft 2B of the slipping clutch 2. (2) The input shaft 3A of the torque converter 3 is integrally connected to the impeller wheel IW.
The output shaft 3B is integrally connected to the turbine wheel TW. The impeller wheel IW and the turbine wheel TW are housed in a sealed housing CH filled with fluid, and the output torque of the slipping clutch 2 is transmitted from the impeller wheel IW to the turbine wheel TW via oil, and the output of the torque converter 3 It is transmitted to the shaft 3B. The torque transmitted to the output shaft 3B of the torque converter 3 is further transmitted to a reverse gear mechanism 4 provided at a subsequent stage. (3) The output shaft 3B of the torque converter 3 is coupled to the drive shaft DS of the reversing gear mechanism 4 via a spline SP,
A drive gear DS1 meshing with a driven gear MS1 formed integrally with the intermediate shaft MS is integrally fixed to the drive shaft DS. (4) A reverse pinion DS is provided on the drive shaft DS and the intermediate shaft MS of the reverse gear mechanism 4 via bearings DJ and MJ, respectively.
3 and a forward rotation pinion MS3 are rotatably supported, and a reverse rotation clutch DS2 comprising a wet multi-plate hydraulic clutch.
And by coupling the forward rotation clutch MS2, each rotates integrally with the shaft. (5) The output shaft OS of the reversing gear mechanism 4 has an output gear OS
1 is fixed and meshes with the reverse rotation pinion DS3 and the normal rotation pinion MS3. Accordingly, the rotation direction of the output shaft OS is reversed between when the forward rotation clutch MS2 is engaged and when the reverse rotation clutch DS2 is engaged. (6) The forward rotation clutch MS2 is constituted by a second slipping clutch capable of performing a slip operation by controlling the clutch operating oil pressure, and the reverse rotation clutch DS2 is generally used in a completely coupled or completely disengaged state. It uses a wet multi-plate hydraulic clutch exclusively for on / off. With this configuration, the torque transmitted from the torque converter 3 is: (A) When the reverse rotation clutch DS2 is engaged, the drive shaft D
The output gear OS1 of the output shaft OS is transmitted to the output gear OS1 of the output shaft OS via the S drive gear DS1, reverse rotation clutch DS2, and reverse rotation pinion DS3, and the rotation direction of the output shaft OS is rotated in the opposite direction to the rotation direction of the drive shaft DS. (B) On the other hand, when the forward rotation clutch MS2 is engaged, the drive gear DS1 of the drive shaft DS and the driven gear MS of the intermediate shaft MS
1, transmitted to the output gear OS1 of the output shaft OS via the forward rotation clutch MS2 and the forward rotation pinion MS3,
Is rotated in the same direction as the rotation direction of the drive shaft DS. Note that, when the forward rotation clutch MS2 is engaged, the rotation direction of the drive shaft DS is reversed at the time of winding up and at the time of lowering, so that the input shaft 3A of the torque converter 3, that is,
The output shaft OS rotates in the same direction at the time of winding up and in the opposite direction at the time of lowering with respect to the rotation direction of the engine.

Next, FIGS. 3 and 4 show the connection of the clutch when the lifting and lowering operations of the suspended load (load) are performed by using the power transmission device for driving the rotary drum having the above configuration and operation. This will be described in detail with reference to FIG.
First, FIGS. 3 and 4 will be briefly described. FIG.
FIG. 5 is a control conceptual diagram for operating a power transmission device for driving a rotary drum, showing a grip position and a first slipping clutch and torque at the time of hoisting and lowering work at a constant engine speed. FIG. 7 is a diagram in which respective operating oil pressures of a converter, a forward rotation clutch (second slipping clutch), and a reverse rotation clutch are associated; FIG. 3 (a)
FIG. 3B shows the time of heavy load and light load hoisting work and the time of heavy load lowering work, and FIG. 3B shows the time of light load lowering work. FIG. 4 is a schematic hydraulic system diagram when hoisting and lowering when the reverse clutch DS2 is OFF and the normal clutch MS2 is ON and the suspended load is heavy. One hydraulic pump supplies oil to the clutch system and the torque converter 3, and the first slipping clutch 2 and the second slipping clutch MS2 are reduced to the command pressure via the proportional solenoid valves 40 and 43. The supplied working oil pressure is supplied. On the other hand, oil is supplied into the torque converter 3 via a torque converter hydraulic pressure adjusting valve, and a part of the oil is used for lubrication of each part. The internal pressure of the torque converter 3 is adjusted by an internal pressure control valve 44.

1) Speed control at the time of load hoisting The control of the hoisting speed is the same as that of the conventional power transmission device. That is, regardless of the weight of the suspended load, as shown in FIGS. 3 and 4, the operating oil pressure of the forward rotation clutch MS2 is set to the rated pressure and the oil pressure of the reverse rotation clutch DS2 is set to 0, and the forward rotation clutch MS2 is completely connected. Then, the operating oil pressure of the first slipping clutch 2 is controlled using, for example, the proportional solenoid valve 40. Further, the internal pressure of the torque converter 3 is maintained at a rated pressure by an internal pressure control valve 44.
As described above, the forward rotation clutch (second slipping clutch) MS2 is completely connected, the reverse rotation clutch is disengaged, and the operating oil pressure of the first slipping clutch 2 is adjusted. Since the rotation speed of the shaft 3A changes and the rotation speed of the output shaft 3B changes accordingly, the rotation speed of the input shaft 3A is increased, that is,
By increasing the operating oil pressure of the first slipping clutch 2, the hoisting speed of the suspended load is increased, and conversely, by decreasing the operating oil pressure, the hoisting speed of the suspended load is decreased.

2) Speed control at the time of load lowering As shown in the control conceptual diagram of FIG. 3, hydraulic pressure control is switched between heavy load lowering and light load lowering, and control is performed as follows. . 2-1) When the heavy load is rapidly dropped, as shown on the left side of FIG. 3A, the operating oil pressure of the first slipping clutch 2 is maintained at a constant low pressure, and the rotation speed of the impeller wheel IW is reduced. At the same time, the internal pressure of the torque converter 3 is reduced to a predetermined low pressure value, and the forward rotation clutch MS2
Is lowered to a value equal to or lower than the low pressure value corresponding to the weight of the suspended load, and the forward rotation clutch MS2 is slipped to rapidly fall. At this time, the hydraulic pressure of the reverse rotation clutch is 0, and the reverse rotation clutch is maintained in a completely disengaged state.
Note that the internal pressure of the torque converter 3 is set to a low pressure value at which the internal oil amount is sufficiently maintained.

2-2) When the heavy load is lowered at a normal speed, the operation of the first slipping clutch 2 is performed while maintaining the operating oil pressure of the forward rotation clutch MS2 and the internal pressure of the torque converter 3 at the rated pressure. This is done by gradually lowering the oil pressure. At this time, the hydraulic pressure of the reverse rotation clutch DS2 is 0, and the reverse rotation clutch is maintained in a completely disengaged state.

2-3) In the case of lowering the light load, after the suspended load is suspended, the control is switched to the lowering of the light load ((b) in FIG. 3) in conjunction with a manual switch or an operation lever. It is done by doing. By this switching, the reverse rotation solenoid valve 42 shown in FIG. 4 is excited to supply the operating oil pressure to the reverse rotation clutch DS2, and at the same time, the operating oil pressure of the first slipping clutch 2 is switched to a preset low pressure value. At this time, the internal pressure of the torque converter 3 and the operating oil pressure of the forward rotation clutch MS2 are rated oil pressures,
It does not change before and after switching. Therefore, the forward rotation clutch MS
After the switching, in addition to the engagement of No. 2, the reverse rotation clutch DS2 is also completely engaged, and the rotation of the drum is mechanically kept stationary. In this state, when the operating lever is operated to the lowering side, the operating oil pressure supplied to the forward rotation clutch MS2 is changed from the rated oil pressure to a predetermined value of low pressure by the proportional solenoid valve 43 shown in FIG.
Is switched from the completely coupled state to the slip coupled state, acting as an auxiliary load (braking force) on the output side of the torque converter 3, and at the same time, the drum starts rotating in the lowering direction. Thereafter, by operating the lever, the operating oil pressure of the slipping clutch 2 gradually increases, the input rotation speed (the rotation speed of the impeller wheel IW) of the torque converter 3 increases, the output torque increases, and the descent speed decreases. Becomes large. By changing the setting value of the operating oil pressure of the forward rotation clutch MS2 to change the size of the auxiliary load, it is possible to finely adjust the lowering speed according to the load.

2-4) The control for raising and lowering the minute amount is not described in the control conceptual diagram of FIG. 3, but at the position of the suspended load for performing the minute amount control, the forward rotation clutch M is controlled.
By controlling the operating oil pressure in S2 and changing the slip ratio of the forward rotation clutch MS2, the rotation speed of the drum can be adjusted, and a small amount of movement can be instantaneously realized. The operating oil pressure of the forward rotation clutch MS2 at this time is controlled as follows. 2-4-1) When a heavy load and a light load are being rolled up,
Since the load is increased via the forward rotation clutch (second slipping clutch) MS2, when approaching the position where the minute amount control is performed, the operating oil pressure is first reduced to slip the forward rotation clutch MS2, and the load torque and The transmission torque of the forward clutch (second slipping clutch) MS2 is increased by balancing the transmission torque of the forward rotation clutch MS2 to maintain the suspended load in a suspended state, and then increasing the operating oil pressure. An ascending speed is obtained, and a small descending speed is obtained by lowering the operating oil pressure.
When the heavy load is being lowered, when approaching the position where the minute amount control is to be performed, first, the hydraulic pressure for operating the first slipping clutch is increased, and the load torque and the turbine torque (brake torque) are balanced to suspend the load. Is maintained in a suspended state, and thereafter, by lowering the operating oil pressure of the forward rotation clutch MS2, the transmission torque of the forward rotation clutch MS2 is reduced, the turbine torque (brake torque) is reduced, and a minute descent speed is obtained.

2-4-2) The lowering of the light load is based on the difference between the torque forcibly delivered by the complete coupling of the reverse clutch DS2 and the brake torque by the slip coupling of the forward clutch MS2. Has become
By increasing the operating oil pressure of the forward rotation clutch MS2, the delivered torque is reduced and a small descending speed is obtained. By decreasing the operating oil pressure, the delivered torque is increased and a small ascending speed is obtained.

The present invention is not limited to the embodiments described above, but can be implemented with appropriate modifications without departing from the technical scope of the present invention. For example, the power transmission device for driving a rotary drum according to the present invention can be applied to an elevator, a construction machine, and the like other than a grab dredger and a crane.

[0027]

According to the first aspect of the present invention having the above configuration and operation, the following effects can be obtained. (1) The responsiveness is improved without providing a separate brake load application mechanism for lowering the light load, the number of components of the reverse gear mechanism is reduced, and the entire power transmission device is reduced in weight and size. (2) When the suspended load is rapidly lowered, it is not necessary to discharge the oil in the torque converter, so that the subsequent hoisting response time is shortened. (3) The rotational speed of the drum can be controlled by adjusting the slip ratio of the forward rotation switching clutch (second slipping clutch) of the reverse rotation gear mechanism disposed on the output side of the torque converter without passing through the torque converter. So
It is possible to instantaneously raise and lower a minute amount, which was difficult in the past, and the assembling work by a crane at a construction site or the like becomes easy.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of a power transmission device for driving a rotary drum according to the present invention.

FIG. 2 is an explanatory diagram for explaining a structure of a reverse gear mechanism according to the present invention.

FIG. 3 is an explanatory diagram of a control concept when operating a power transmission device for driving a rotary drum according to the present invention.

FIG. 4 is a schematic hydraulic system diagram of a power transmission device for driving a rotary drum according to the present invention.

FIG. 5 is a longitudinal sectional view showing a conventional power transmission device for driving a rotary drum.

[Explanation of symbols]

 Reference Signs List 1 power transmission device 2 first slipping clutch 2A input shaft 2B output shaft 3 torque converter 3A input shaft 3B output shaft 4 reverse gear mechanism 5 casing DS2 reverse clutch (reverse switching clutch) MS2 forward clutch (for forward switching) Clutch) OS output shaft

Claims (1)

[Claims] An input shaft of a torque converter includes a first slipping clutch, and an output shaft of the torque converter has a rotating drum attached to the output shaft thereof by a forward switching clutch and a reverse switching clutch. In a power transmission device for driving a rotary drum provided with a reverse gear mechanism for switching the rotation direction, the forward switching clutch is constituted by a second slipping clutch, and the reverse switching clutch is constituted by a wet multi-plate hydraulic clutch. A rotating drum configured to control a rotation speed of an output shaft of the reverse gear mechanism by a combination of the first slipping clutch and the second slipping clutch. Power transmission device for driving.