JPH0372557B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and device for detecting the amount of cargo handled by a grab bucket cart, and more particularly to a method and device for detecting the amount of cargo handled by a grab bucket cart that picks up loose materials such as coal, ore, or gravel.

Generally, when handling bulk materials such as coal, ore, or gravel from a ship or the like, a grab bucket as shown in FIG. 1 is used.

In Figure 1, the grab bucket 2 is a symmetrical 2
It is composed of shells 2A and 2B, and each shell 2
A and 2B are rotatably joined at a joining portion 4. One end of an opening/closing rope 6 is connected to the joint portion 4 . Moreover, one end of shell hanging jigs 3A, 3B is connected to the bottom surface of each shell 2A, 2B, and the other end of these shell hanging jigs is connected to the support member 8. One end of a support rope 10 is connected to the support member 8 .

The other end of the opening/closing rope 6 is wound around an opening/closing drum 16 via a roller 12. The opening/closing drum 16 is connected to the rotating shaft of the opening/closing motor 14 via a speed reducer (not shown).

The other end of the support rope 10 is wound around a support drum 22 via a roller 18. This support drum 22 is connected to the rotating shaft of the support motor 20 via a speed reducer (not shown).

When such a grab bucket is used to unload the bulk materials from a ship or the like, the bulk materials are weighed and the amount of the unloaded materials is detected.

Conventional systems for detecting the amount of unloaded bulk materials of this type are to detect the amount of unloaded materials using a weighing device (merik) installed on the in-machine conveyor downstream of the hopper, or to detect the amount of unloaded materials on the receiving (ground) conveyor further downstream. One of the methods used was to detect the amount of cargo handled using a weighing device provided.

However, with this conventional cargo handling amount detection method,
Since the crane is installed outdoors and on a quay, there is a problem in that detection must be carried out in adverse environments such as wind and rain, dust, and salt damage, as well as in adverse environments such as vibration and dust generation during cargo handling. There was a problem in that it was necessary to use a weighing device to detect the amount of cargo being handled.

That is, since the amount of cargo to be handled is detected under the above-mentioned adverse environment, there is a drawback that not only the accuracy of the weighing device is reduced, but also a great deal of labor is required for its maintenance.

In addition, in order to know the amount of cargo handled, it is necessary to flow the bulk material to a weighing device, which has the disadvantage that a certain amount of time delay is unavoidable.

Furthermore, when a weighing device is installed on the receiving (ground) conveyor, if the configuration is such that multiple cranes are used to load cargo onto a single ground conveyor, it is difficult to know the unloaded amount of each crane. This also had the disadvantage of making it impossible to manage the cargo handling of individual cranes.

The present invention has been made in order to solve the problems of the conventional technology, and is capable of accurately detecting the amount of cargo handled during cargo handling using a grab bucket by accurately detecting the amount of grasping for each grab of the grab bucket. The first objective is to provide a method for detecting the amount of cargo handled by a grab bucket cart. A second object of the present invention is to provide a grab bucket cart cargo handling amount detection device for carrying out the grab bucket cart cargo handling amount detection method described above.

A first object of the present invention is to handle cargo using a grab bucket cart, which is equipped with an opening/closing motor that opens and closes the grab bucket cart by winding or unwinding an opening/closing rope, and a support motor that reciprocates the grab bucket cart by winding or unwinding a support rope. In the method of detecting the amount, the current value of the opening/closing motor and the current value of the support motor are measured when rotating at a constant speed other than when accelerating or decelerating, and from these measured current values, the current value of the opening/closing motor and the current value of the supporting motor are measured. This can be achieved by a method for detecting the amount of cargo handled by a grab bucket cart, which is characterized in that the amount of cargo handled by a grab bucket cart is detected by detecting the amount of cargo being grabbed at each time, calculating and storing the amount of grasped cargo.

A second object of the present invention is to detect the current values of the opening/closing motor that opens and closes the grab bucket by winding or unwinding the opening/closing rope and the support motor that reciprocates the grab bucket by winding or unwinding the support rope. A current detector and a total value of each current value detected by the current detector when the opening/closing motor and the support motor are rotating at a constant speed other than during acceleration or deceleration are calculated for each grab bucket strike. a calculation storage device that calculates and stores the amount of gripping; a timer section connected to the calculation storage device that operates during cargo handling to determine the loading time; and a cargo handling device that displays cargo handling efficiency from the calculation amount of the gripping amount and the loading time. This can be achieved by the second invention, which includes an efficiency display and an integrated cargo handling amount display that displays the calculation amount of the grasping amount.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 5.

In cargo handling using a grab bucket cart, a support motor for hoisting and lowering the grab bucket cart, and an opening/closing motor for opening/closing, hoisting and lowering the grab bucket cart are installed.When hoisting and lowering the grab bucket cart, these two motors are installed. The motor is operated in such a manner that the load (weight of bulk goods) is shared by the two motors, and the load ratio of these two motors is controlled.

When we investigated the relationship between the current flowing through the opening/closing motor and the support motor and the gripping amount of the grab bucket when the opening/closing motor and the support motor were rotating at a constant speed, avoiding the acceleration and deceleration of the opening/closing motor and the support motor, we found that Figs. The results shown in Figure 4 were obtained.

FIG. 2 shows the relationship between the current value of the opening/closing motor and the gripping amount of the grab bucket, and FIG. 3 shows the relationship between the current value of the support motor and the gripping amount of the grab bucket.

Further, FIG. 4 shows the relationship between the current value when the current flowing through the opening/closing motor and the current flowing through the support motor are added and the grip amount of the grab bucket.

As is clear from the graphs in Figures 2 to 4, the value of the current flowing through the opening/closing motor and the support motor is almost proportional to the gripping amount of the grab bucket. There is a strong proportional relationship between the total value of the current of the support motor and the gripping amount of the grab bucket cart, and by detecting this total value, it is possible to know the cargo handling amount more accurately.

The method for detecting the amount of cargo handled by a grab bucket cart according to the present invention has been developed from this point of view. It is characterized by detecting the amount of cargo handling by calculating and storing.

FIG. 5 is a diagram showing an embodiment of an apparatus for carrying out the method for detecting the cargo handling amount of a grab bucket cart according to the first invention described above.

In FIG. 5, parts corresponding to those in FIG.
0 is connected, and the other end of the opening/closing rope 6 is connected to the roller 12.
The other end of the support rope 10 is wound around the support drum 12 via a roller 18. The opening/closing drum 16 is connected to the output shaft of the opening/closing motor 14, and the support drum 22
is connected to the output shaft of the support motor 20.

The opening/closing motor 14 and the support motor 22 each have a resistance
R ₁ and R ₂ are connected. Each resistor R ₁ , R ₂ is connected to a current detector 24 . This current detector 24 is for detecting current values of the opening/closing motor 14 and the support motor 20.

The current detector 24 is connected to an arithmetic memory 26. This calculation memory 26 is a current detector 24
This is to calculate and store the gripping amount of the grab bucket from the current value detected. The calculation function in the calculation memory 26 operates to calculate the gripping amount of the grab bucket by multiplying the detected current value by a proportionality constant, for example.

The grasping amount of the grab bucket calculated by the calculation storage unit 26 is, for example, sequentially integrated and outputted to a cargo handling efficiency (T/H) display 31 or a cumulative cargo handling amount display 32 provided on an operation disk or the like. The integrated total value is displayed.

A timer unit 41 that operates during cargo handling is connected to the calculation storage unit 26, and is configured so that the timer unit 41 is activated at the same time as the cargo handling starts, and its signal is input to the grasping amount calculation storage unit 26. By inputting such a timer signal into the calculation storage device 26, the stored cargo handling amount is divided by time to calculate the cargo handling efficiency (T/H), and the value is displayed on the cargo handling efficiency display section 31. It's becoming like this. If the crane stops handling cargo due to a failure or the like, the net cargo handling efficiency can be displayed on the integrated cargo handling amount display 32 by holding the timer unit. These cargo handling efficiencies may be calculated at arbitrary time intervals, and in that case, the cargo handling efficiency based on the previous calculation is displayed between one calculation and the next calculation.

Furthermore, the properties (brand or particle size) of the bulk materials handled
Even if the grab bucket is changed or the grab bucket is replaced, the weight of the grabbed bulk material can be easily known by calibrating the weight of the grab bucket without a load (in a state in which no loose material is being gripped). In this case, the calibration is performed by, for example, the gripping amount calculation memory 26.
This can be done by adjusting the zero adjustment volume 33 connected to.

In FIG. 5, reference numeral 34 indicates a command signal switch for giving a reading command to the calculation memory 26, and reference numerals 21 and 22 indicate a maximum weight setting device for one handful of loose objects and an alarm device. Generally, the grab bucket used differs depending on the nature of the bulk material to be handled, and the maximum weight of the bulk material that can be grabbed in one grip is determined by the weight of the grab bucket and the rated load of the crane. The setting device 21 sets this weight and inputs it to the alarm device 22. The alarm device 22 compares the inputted maximum weight with the value of the amount of one grab of the grab bucket calculated by the calculation memory 26, and issues an alarm if the relationship of the set maximum weight < the calculated amount of one grip. Operate. This function may be configured to be included in the calculation storage 26. This makes it possible to notify the operator that the crane has exceeded its rated load (overload).

According to the grab-bucket cargo handling amount detection device according to the present invention described above with reference to FIG. can be displayed sequentially on the operation panel, etc., and can notify operators very quickly (immediately) and accurately. Therefore, it is an extremely excellent monitoring device not only for cargo handling management but also for equipment protection. can be provided. Furthermore, it is also possible to accurately control the amount of cargo handling based on the detection results.

Furthermore, as mentioned above, there is an extremely strong correlation between the current values of the opening/closing motor and support motor and the gripping amount (hoisting load) of the grab bucket. Even with this method, it is possible to obtain a detection accuracy that is not inferior to, or even exceeds, that of the conventional direct detection method.

Furthermore, according to the cargo handling amount detection device explained above, since the main parts are electrically constructed, there are no mechanical parts, the life is semi-permanent, maintenance is easy, and weight errors due to aging do not occur. Effects can also be obtained.

In addition, the cargo handling amount detection device described above can be easily installed on existing equipment, and therefore, when implementing it, there is an advantage that almost no modification of the equipment is required. .

As is clear from the above description, according to the present invention, the amount of bulk materials to be handled can be detected very quickly and accurately without any time delay, and the grab bucket can be used which is highly durable and easy to maintain and inspect. A cargo handling amount detection method and device are obtained.

[Brief explanation of drawings]

Figure 1 is a schematic configuration diagram of the grab bucket, Figure 2 is a graph illustrating the relationship between the current value of the opening/closing motor and the gripping amount of the grab bucket, and Figure 3 is a graph showing the relationship between the current value of the support motor and the gripping amount of the grab bucket. The illustrated graph, FIG. 4 is a graph illustrating the relationship between the total current value of the opening/closing motor and the support motor and the grasping amount of the grab bucket cart, and FIG. 5 is an example of the grab bucket cargo handling amount detection device according to the present invention. FIG. 2 is an explanatory diagram showing the configuration of. 2...Grab bucket, 6...Opening/closing rope, 1
0...Support rope, 14...Opening/closing motor, 20...
...Support motor, 21...Gripping amount setting device, 22...
Alarm device, 24... Current detector, 26... Arithmetic unit, 31... Cargo handling efficiency indicator, 32... Cumulative cargo handling amount indicator.

Claims (1)

[Scope of Claims] 1. The cargo handling capacity of a grab bucket cart equipped with an opening/closing motor that opens and closes the grab bucket cart by winding or unwinding an opening/closing rope, and a support motor that reciprocates the grab bucket cart by winding or unwinding a support rope. In the detection method, the current value of the opening/closing motor and the current value of the support motor are measured while rotating at a constant speed other than during acceleration or deceleration, and the total value of these measured current values is used to determine the current value of the grab bucket. A method for detecting the amount of cargo handled by a grab bucket cart, characterized in that the amount of cargo handled by a grab bucket is detected by detecting the amount of grasping each time, calculating and storing the amount of grasping. 2. A current detector that detects the current value of the opening/closing motor that opens and closes the grab bucket by winding or unwinding the opening/closing rope and the support motor that reciprocates the grab bucket by winding or unwinding the support rope, and a current detector that detects these currents. an arithmetic storage device that calculates and stores the amount of grip per grab bucket from the total value of each current value detected when the opening/closing motor and the support motor rotate at a constant speed other than when accelerating or decelerating; , a timer section connected to the calculation memory and operated during cargo handling to determine the cargo handling time, a cargo handling efficiency indicator that displays the cargo handling efficiency from the calculated amount of the grabbed amount and the cargo handling time, and a cargo handling efficiency display that displays the calculated amount of the grabbed amount. A grab bucket cargo handling amount detection device including a cumulative cargo handling amount indicator.