JPH06329391A - Load detector for winch - Google Patents

Abstract

PURPOSE:To improve stability of a main body and load detecting accuracy by arranging a generating torque detecting means on the side where rotation is checked to enable hoisting and lowering by a hydraulic motor, separately from a winch drum among a ring gear and a carrier of a planetary speed reduction mechanism connected to the motor. CONSTITUTION:A planetary speed reduction mechanism 20 connected to an output shaft of a motor 10 is composed of a ring gear 21 fixed to the inner peripheral surface of a winch drum 30, a sun gear 22 connected to an output shaft 10a of the hydraulic motor 10, a planetary gear 23 to mesh with these and a carrier 24 connected to the planetary gear 23, and is constituted in such a way that when the sun gear 22 is rotated in a condition of checking rotation of the carrier 24, the planetary gear 23 rotates, and rotates the ring gear 21, and rotates the winch drum 10. A torque detecting means 50 composed of a shaft 51 connected to this carrier 24 by a spline, a lever 52 rotatable integrally on the shaft 51 and a load cell 53 on the tip, is provided, and torque of the carrier 24 is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winch load detecting device provided in a crane or the like.

[0002]

2. Description of the Related Art Generally, a crane is provided with a load detecting device for preventing an overload of a winch, and when a detected load (for example, tension of a hoisting rope) exceeds a predetermined value, a worker is instructed to do so. An alarm is issued and winding is automatically stopped. Conventional load detection methods include the following (1) to (3). (1) Three-point roller system: For example, as shown in FIG. 7, three sheaves 101, 102, and 103 are wound around a hoisting rope RP, and a load in the direction of the arrow applied to the central sheave 102 ( (Depending on the rope tension) is detected by a load cell or the like. (2) Rope end method: Applied to a type in which a hook is passed through a hoisting rope hanging from the top sheave of a boom and the rope end is fixed to the boom. A load cell is interposed between the boom and the rope end. Wear it and detect the tension of the hoisting rope. (3) Hoisting rope tension detection method: The tension of the rope for hoisting the boom is detected, and the hoisting rope tension is indirectly calculated by adding the boom angle, boom length, and the like. (4) Winch drum load detection method: The winch device itself is rotatably provided with respect to the working machine body, and
A load cell is provided between the winch device and the work machine main body at a position separated from the center of rotation, and the rope tension is calculated based on the output of the load cell and the boom hoisting angle (see Japanese Utility Model Laid-Open No. 60-193389). ).

[0003]

However, each of the load detecting methods (1) to (4) has the following drawbacks. In the three-point roller system of (1), the hoisting rope has a plurality of sheaves.
Since the rope is complicatedly wound around, the hoisting rope is prone to wear and fatigue, and strand breakage easily occurs. In addition, since the load detector is generally attached to the tip of the boom, the stability of the crane body is impaired. The rope end method of (2) cannot be applied to the type in which the hook is attached to the rope end because the load cell cannot be fixed. In the undulating rope method of (3), the undulating rope tension cannot be accurately detected, for example, when the work radius is increased with a long boom to suspend a light load, and the detection accuracy decreases. Further, the undulating rope is generally wound around ten or more sheaves, and the sheave resistance acts in the opposite direction according to the raising and lowering of the boom, so that the load detection accuracy decreases. Furthermore, since it is necessary to continuously detect the working state, a boom angle meter, a boom length meter, etc. are required in addition to the load detector, and the calculation processing becomes complicated. Also in the winch drum load detection method of (4), it is necessary to detect the boom angle in order to obtain the hoisting rope tension, and a boom angle meter is required in addition to the load detector.

An object of the present invention is to provide a winch load detecting device which solves all the above problems.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1 showing an embodiment, the present invention will be described. In the present invention, a motor 10 and an output shaft 10a of the motor 10 are connected to reduce the rotation of the output shaft 10a. Planetary reduction mechanism 20 and this planetary reduction mechanism 2
0 of the ring gear 21 and the carrier 24 and the winch drum 30 integrated with the ring gear 21.
Also, the present invention is applied to a load detection device used for a winch in which one of the carriers 24, which is separate from the winch drum 30, is prevented from rotating so that the hydraulic motor 10 can wind and lower the wind. Then, the torque detecting means 53 for detecting the torque generated in one of the ring gear 21 and the carrier 24, which is separate from the winch drum 30, is provided, thereby solving the above problems. Especially claim 2
As shown in FIG. 5, the present invention is applied to a winch capable of so-called free fall, and includes a brake drum 81 integrated with one of the ring gear 21 and the carrier 24, which is separate from the winch drum 30, and a brake. Band 9
Brake device 9 that brakes the brake drum 81 by 1
0 and the brake band 9 is detected by the torque detecting means 53.
The tension of 1 is detected. A third aspect of the present invention is a winding layer detecting means 60 (FIG. 4) for detecting the winding layer of the winch drum 30, and a hoisting rope RP based on the output of the winding layer detecting means 60 and the output of the torque detecting means 53.
And a calculation means 71 for calculating the tension of the.

[0006]

The torque generated in one of the ring gear 21 and the carrier 24, which is separate from the winch drum 30, depends on the tension of the hoisting rope RP. Therefore, by detecting this, an accurate load detection result can be obtained. Is obtained.

Incidentally, in the section of means and action for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for making the present invention easy to understand. It is not limited to.

[0008]

【Example】

-First Embodiment- A first embodiment of the present invention will be described with reference to Figs. FIG. 1 is a sectional view showing a winch in this embodiment. The winch supported by the main frame 1 is a hydraulic motor 10
And a planetary reduction mechanism 20 for reducing the rotation of the hydraulic motor 10.
A winch drum 30 rotated via the planetary speed reduction mechanism 20, a negative hydraulic brake device 40 for braking the input side of the planetary speed reduction mechanism 20, and a planetary speed reduction mechanism 2
A torque detection device 50 for detecting the torque acting on the carrier 24 of 0, and a wound layer detection device 60 shown in FIG.
A hoisting rope RP is wound around the winch drum 30.

The planetary speed reduction mechanism 20 includes a winch drum 30.
Of the ring gear 21 fixed to the inner peripheral surface of the hydraulic motor 1
The state in which the rotation of the carrier 24 is blocked includes the sun gear 22 connected to the zero output shaft 10a, the planet gear 23 meshed with the sun gear 22 and the ring gear 21, and the carrier 24 connected to the planet gear 23. And Sun Gear 2
When 2 rotates, the ring gear 21 rotates due to the rotation of the planetary gear 23, and the winch drum 30 rotates.

As shown in the enlarged view of FIG. 2, the brake device 40 has the sun gear 22 inside the bearing case 41.
Brake disc 4 splined to the shaft 22a of the
2, a piston 43 housed in the case 41, and a brake spring 44 for urging the piston 43 toward the disc 42 side.
And a lining 42a on both sides of the disc 42,
42b is attached. When oil is not supplied to the hydraulic chamber 45, the piston 43 presses the disk 42 against the case 41 by the urging force of the spring 44, and brakes the sun gear 22, that is, the winch drum 30.
When pressure oil is supplied to the hydraulic chamber 45 via the oil passage 46, the piston 43 moves rightward in the drawing against the urging force of the spring 44, and the braking is released. In FIG. 1, BR indicates a rolling bearing.

As shown in FIG. 3, the torque detecting device 50 includes a shaft 51 splined to the carrier 24 and a lever 5 rotatable integrally with the shaft 51.
2 and a load cell 53 interposed between the tip of the lever 52 and the main frame 1. The torque acting on the lever 52, that is, the carrier 24 when the winch drum 30 rotates is detected by the load cell 53. The detection output of the load cell 53 is input to the controller 71 shown in FIG. Here, the lever 52 is originally for taking a rotational reaction force of the ring gear 21, and is usually directly connected to the frame 1. However, in the present embodiment, the lever 52 is for detecting the torque of the carrier 24. A load cell 53 is interposed between 52 and the frame 1. That is, in the present embodiment, a conventional mechanism is used to detect the torque of the carrier 24, which can simplify the configuration.

The wound layer detecting device 60, as shown in FIG.
A lever 61 rotatably provided on the frame 2, a roller 62 attached to the tip of the lever 61, and a lever 6
A spring 63 for urging 1 toward the winch drum 30 and an angle sensor 64 for detecting the angle of the lever 61 are provided. Since the lever 61 rotates in the direction of the arrow in the drawing as the number of layers wound on the winch drum 30 increases, the winding layer of the winch drum 30 can be detected by detecting the angle of the lever 61. The output of the angle sensor 64 is input to the controller 71, and the controller 71 calculates the tension of the hoisting rope RP based on the outputs of the angle sensor 64 and the load cell 53, as described later.

Next, the operation of the embodiment will be described. When the winch operation lever (not shown) is in the neutral position, the hydraulic motor 10 is stopped, pressure oil is not supplied to the hydraulic chamber 45 (FIG. 2), and the brake device 40 operates to operate the winch 10. It has stopped. When the operation lever is operated in the winding direction in this state, pressure oil is supplied to the hydraulic chamber 45, the brake device 40 is opened, and the hydraulic motor 1
0 is driven, and the sun gear 22 integrated with the output shaft 10a of the hydraulic motor 10 rotates. At this time, the shaft 5
1, because the rotation of the carrier 24 is blocked via the lever 52 and the load cell 53, the rotation of the sun gear 22 causes the planet gear 23 to rotate while rotating the ring gear 21, which causes the winch drum 30 to rotate and wind. Is done.

Here, the load cell 53 detects the torque acting on the lever 52, that is, the carrier 24, and inputs it to the controller 71, while the winding layer detector 64 controls the lever 61.
Angle, that is, the winding layer of the hoisting rope RP is detected and input to the controller 71. The controller 71
Based on these input values, hoisting rope RP as follows
Calculate the tension of. That is, if the torque generated in the winch drum 30 via the hoisting rope RP is Td, the torque generated in the carrier 24 is Tc, and the total reduction ratio of the planetary reduction mechanism 20 is i,

## EQU1 ## The relationship of Td: Tc = i: (i + 1) holds. Therefore, the torque Td generated in the winch drum 30 can be obtained by substituting the output value Tc of the load cell 53 and the preset total reduction ratio i of the planetary reduction mechanism 20 into the above equation.

On the other hand, the drum torque Td, the distance R obtained by adding the winding layer of the rope RP to the radius of the rope winding portion of the winch drum 30, and the tension T of the hoisting rope RP to be obtained are:

## EQU00002 ## The relationship of Td = T.multidot.R holds. Since R can be obtained from the output of the wound layer detection device 60, the rope tension T can be calculated by substituting Td and R in the above equation. Then, when the rope tension T exceeds a predetermined value, a warning is issued, or the winding is automatically stopped. In the above, the case of hoisting is described, but the load can be similarly detected when hoisting. Further, the load can be similarly detected when the operation lever is at the neutral position and the winch drum is stopped.

In the configuration of the above embodiment, the load cell 53 constitutes the torque detecting means, the winding layer detecting device 60 constitutes the winding layer detecting means, and the controller 71 constitutes the calculating means.

-Second Embodiment- Next, a second embodiment of the present invention will be described with reference to FIGS. The same parts as those in FIG. 1 are designated by the same reference numerals, and different points will be mainly described. The winch of the present embodiment is capable of so-called free fall in which, in addition to hoisting and lowering by the power of the hydraulic motor 10, hoisting is performed by the weight of the suspended load. Therefore, as shown in FIG. 5, a brake drum 81 that rotates integrally with the shaft 51 is provided,
A brake band 91 that constitutes a brake device 90 (FIG. 6) is wound around the brake drum 81. When the brake pedal (not shown) is depressed, the rod 92
The brake band 91 is wound around the brake drum 81 via the link 93 and the brake drum 81 is braked. A load cell 53 similar to that described above is interposed between the fixed end of the brake band 93 and the frame 1, and the tension of the brake band 93 (which depends on the torque of the carrier 24) is detected by the load cell 53, and the controller 71 is operated. Entered in. Other configurations are shown in FIG.
Is the same as.

When the braking device 90 is in the braking state,
Since the rotation of the carrier 24 is blocked by the brake drum 81, the hydraulic motor 10 winds and lowers the winder in accordance with the operation of the winch operating lever. At this time, the load cell 53 and the winding layer detecting angle sensor. 64
The tension of the hoisting rope RP is calculated in the same manner as described above based on the output of. On the other hand, when the operation of the brake pedal is released when the hydraulic motor 10 is stopped and the two brake devices 40 and 90 are both in the braking state, only the brake device 90 is released and the carrier 24 rotates, that is, the planetary gear 23. Revolution is allowed. Therefore, the winch drum 30 rotates integrally with the ring gear 21 due to the weight of the suspended load, and free fall is performed. To stop the free fall, depress the brake pedal and press the brake device 90.
Should be activated. Even when the free fall is stopped by the operation of the brake device 90, the load can be detected in the same manner as described above.

Although an example using the hydraulic motor 10 has been shown above, an electric motor may be used instead of the hydraulic motor 10. Further, in the above description, since the winch drum 30 of the multi-layer winding is used, the rope tension is obtained in consideration of the output of the winding layer detecting device 60. However, when the winch drum of the single layer is used, the winding layer detecting device is obtained. 60 is unnecessary, and the rope tension may be calculated only from the output of the load cell 53 and the reduction ratio of the planetary reduction mechanism 20. Further, since the torque of the carrier 24 detected by the load cell 53 depends on the rope tension, the rope tension is not specifically calculated, and the above-described control is performed depending on whether the output itself of the load cell 53 is a predetermined value or more. May be.
In the above, the ring gear 21 is attached to the winch drum 30.
Although the example in which the torque of the carrier 24 is detected by the torque detection device 50 is shown together with the above, the carrier 24 is integrated with the winch drum 30 and the torque of the ring gear 21 is detected by the torque detection device. It may be configured to.

[0020]

According to the present invention, in a winch including one of a ring gear and a carrier of a planetary speed reduction mechanism and an integral winch drum, one of the ring gear and the carrier is separated from the winch drum. Since the generated torque is detected, the following effects can be obtained. (1) Since the load can be detected without complicatedly winding the hoisting rope around the sheave, wear and fatigue of the hoisting rope can be suppressed to a minimum and the life of the hoisting rope can be extended. (2) Since the load detector is provided on the winch side rather than the boom tip, the stability of the crane body can be secured. (3) It can also be applied to a type in which the hook is attached to the rope end. (4) The load can be accurately detected during hoisting and lowering regardless of the boom length and work radius. (5) Boom angle meter and boom length meter are unnecessary,
The configuration is simplified and there is no need to perform complicated arithmetic processing. In particular, according to the invention of claim 2, in the winch capable of free fall, the tension of the brake band (which depends on the tension of the hoisting rope) is detected by the torque detecting means, so that the conventional configuration is utilized. The configuration can be simplified. According to the third aspect of the present invention, the tension of the hoisting rope is calculated in consideration of the output of the torque detecting means and the winding layer of the winch drum. Therefore, the winch drum of the multi-layer winding is used. Depending on the case, the load can be detected accurately.

[Brief description of drawings]

FIG. 1 is a sectional view showing an overall configuration of a winch according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a part of FIG.

FIG. 3 is a diagram showing a configuration of a torque detection device, as seen from a line III-III in FIG. 1.

FIG. 4 is a diagram showing a configuration of a wound layer detection device.

FIG. 5 is a sectional view showing the overall structure of a winch according to a second embodiment.

FIG. 6 is a view showing the configuration of the torque detection device as seen from the line VI-VI in FIG. 5.

FIG. 7 is a diagram showing an example of a conventional load detection method.

[Explanation of symbols]

 1 Main Frame 10 Hydraulic Motor 20 Planetary Reduction Mechanism 21 Ring Gear 22 Sun Gear 23 Planetary Gear 24 Carrier 30 Winch Drum 40,90 Brake Device 50 Torque Detecting Device 53 Load Cell 60 Winding Layer Detecting Device 64 Angle Sensor 71 Controller 81 Brake Drum RP Winding rope

Claims (3)

[Claims] 1. A motor, a planetary speed reduction mechanism that is connected to an output shaft of the motor to reduce the rotation of the output shaft, and a winch drum that is integral with one of a ring gear and a carrier of the planetary speed reduction mechanism. A load detection device used for a winch capable of hoisting and lowering by a hydraulic motor by blocking the rotation of one of the ring gear and the carrier separate from the winch drum, A load detecting device for a winch, comprising a torque detecting means for detecting a torque generated on one side separate from the winch drum. 2. A brake drum that is integrated with one of the ring gear and the carrier, which is separate from the winch drum, and a brake device that brakes the brake drum with a brake band. The winch load detection device according to claim 1, wherein the tension of the brake band is detected. 3. A winding layer detecting means for detecting a winding layer of the winch drum, and a calculating means for calculating a tension of a hoisting rope based on an output of the winding layer detecting means and an output of the torque detecting means. The winch load detection device according to claim 1 or 2, further comprising: a winch load detection device.