JP3281481B2 - Crane load calculation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crane load calculating device for accurately detecting an actual load of a suspended load lifted by a crane, and more particularly to a device for calculating an actual load using an up-and-down rope tension.

[0002]

2. Description of the Related Art There is known a load calculating device which detects the tension of a hoisting rope for raising and lowering a boom and calculates the actual load of a suspended load (for example, see Japanese Patent Application Laid-Open No. 58-148187). This type of load calculating device includes a load detector that detects an up-and-down rope tension, an angle detector that detects an up-and-down angle of a boom,
A storage unit for storing a total rated load according to the boom angle. Here, the rated total load refers to the limit load of a suspended load that can be lifted by the crane from the viewpoint of preventing the crane from falling or being damaged in consideration of the stability of the body of the crane and the strength of the components thereof. The actual load W calculated by this type of load calculation device is expressed by equation (1).

(Equation 1)

[0003] In equation (1), T _L is the hoisting rope tension when an actual suspended load is hung, T ₀ is the hoisting rope tension due to the boom weight when there is no load (no lifting), and T ₂ is the crane weight. The undulating rope tension when a suspended load having the same weight as the rated total load is hung, W _C indicates the rated total load. T ₀ , T ₂ , and W _{C in} equation (1) are all stored in the storage unit.
T _L is a value obtained by the load detector. Note that (1) the T ₂ are may be a hoist cable tension when the hanging a predetermined known weight of the suspended load, W _C in this case is predetermined known weight.

[0004] The hoisting rope tension acting on the hoisting rope changes depending on the weight of the suspended load and the weight of the boom itself, and also changes with the boom hoisting angle. However, even if the boom angle is the same, if the boom length is changed according to the working conditions or the boom is replaced due to its service life, etc., errors in the weight and welding amount of the pipe material forming the boom will occur. Etc., the boom weight changes, and the undulating rope tension changes accordingly. However, since the conventional load calculating device calculates the actual load without taking into account the hoisting rope tension due to the boom weight, the calculated value often differs from the actual value.

To solve such a problem, Japanese Patent Publication No.
The overload detection device described in No. 4516 calculates the difference between the measured value of the hoisting rope tension due to the boom weight and the theoretical design value, and then measures the hoisting rope tension with the actual suspended load suspended. The sum of the measured value and the above-described difference is defined as the actual load. In this way, since the actual load can be calculated in consideration of the error of the boom weight, the calculation accuracy of the actual load increases, and the determination of the overload becomes accurate.

[0006]

On the other hand, since the hoisting rope tension due to the boom weight changes according to the boom hoisting angle, the aforementioned difference also changes according to the boom hoisting angle. Therefore, in order to calculate the actual load, the hoisting rope tension due to the boom weight is actually measured for the entire range of the operable boom hoisting angle, and the measured result and the corresponding theoretical value in design are stored in a memory in advance. Need to be kept. For this reason, a large-capacity memory is required, resulting in an increase in cost.

In particular, in a tower crane in which the boom and the jib can be raised and lowered independently or simultaneously, the lifting rope tension that raises and lowers the boom is affected by both the boom weight and the jib weight, and the lifting rope tension also depends on the working posture. Change. For this reason, the up-and-down rope tension must be stored in the memory for each of the different postures, which requires a large-capacity memory and a long time for storing the memory. In order to reduce the storage time in the memory, it is conceivable to sequentially store the hoisting rope tension at the point where the boom or jib is actually raised or lowered. The actual load has to be calculated, so that the calculation time of the actual load becomes longer and the calculation accuracy becomes worse.

When the boom is tilted at an angle other than the actually measured angle, the tension of the rope is measured and stored at several points within the range of the operable boom angle. It is also conceivable to predict the undulating rope tension by approximation means such as proportional interpolation based on. However, in this case, the calculation accuracy may be reduced. Furthermore, in addition to the deviation due to the boom weight described above, the undulating rope tension detected by the load detector
It also includes the zero point shift of the load detector itself, and unless the calculation is performed in consideration of this shift, an accurate calculation result cannot be obtained.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a load calculating device for a crane in which the amount of correction of an up-and-down rope tension detected by a load detecting means is easily and quickly obtained, and the calculation accuracy of an actual load is improved. is there.

[0010]

The present invention will be described with reference to the claims correspondence diagrams of FIGS. In FIG. 1, components corresponding to claim 1 are indicated by solid lines, and components corresponding to claims 2 to 5 are indicated by broken lines. In FIG. 2, the components corresponding to claim 6 are indicated by solid lines, and the components corresponding to claims 7 to 10 are indicated by broken lines. According to the first aspect of the present invention, there is provided an angle detecting means 201 for detecting an up-and-down angle of a boom, a load detecting means 202 for detecting an up-and-down rope tension acting on an up-and-down rope for raising and lowering the boom, a detected boom-up and down angle and an up-and-down state. The present invention is applied to a load calculating device of a crane provided with an actual hanging load calculating means 203 for calculating the actual load of the hanging load based on the rope tension, and the undulation caused by the difference between the actual boom weight and the designed boom weight. Up-and-down rope tension deviation calculating means 204 for calculating the amount of deviation between the measured value of the rope tension and the theoretical value in design, and an error amount that is included in the up-and-down rope tension detected by the load detection means 202 and does not depend on the boom angle. Load detection error calculation means 205 for calculating the error of the load detection means itself,
A correction amount calculation for calculating a correction amount of the undulation rope tension detected by the load detection means 202 based on the deviation amount of the undulation rope tension calculated by the step 04 and the error amount calculated by the load detection error calculation means 205. Means 206
The actual suspension load calculating means 203 is configured to calculate the actual load of the suspended load based on the correction amount.
According to a second aspect of the present invention, in the load calculation device for a crane according to the first aspect, the amount of change in the hoisting rope tension when the actual boom weight is heavier or lighter than a predetermined weight by a predetermined weight is determined. A change amount calculating means 207 for calculating according to the angle, and based on the change amount of the hoisting rope tension calculated by the change amount calculating means 207, the undulation caused by the difference between the actual boom weight and the designed boom weight. The up-and-down rope tension deviation calculating means 204 is configured to calculate the deviation amount between the actually measured value of the rope tension and the theoretical value in design according to the boom undulation angle. According to a third aspect of the present invention, in the crane load calculating device according to the second aspect, when the boom hoisting angle is the first angle, the measured value of the hoisting rope tension detected by the load detecting means 202 and First calculation of the amount of deviation from the theoretical value in design
An angle shift calculating means for calculating a shift amount between an actually measured value of the up-and-down rope tension detected by the load detecting means and a designed theoretical value when the boom hoisting angle is the second angle; Calculating means 209 for calculating the amount of deviation of each undulation rope tension calculated by the first angle deviation calculating means 208 and the second angle deviation calculating means 209 and the amount of change when the angle is the first angle or the second angle. On the basis of the respective amounts of change calculated by the means 207, the difference between the measured value of the hoisting rope tension caused by the difference between the actual boom weight and the designed boom weight and the designed theoretical value is calculated as the boom hoisting angle. The up-and-down rope tension deviation calculating means 204 is configured to calculate according to the following. According to a fourth aspect of the present invention, there is provided the crane load calculating device according to the third aspect, wherein the amount of deviation of each hoist rope tension calculated by the first angle shift calculating means 208 and the second angle shift calculating means 209 is equal to Self-weight deviation prediction for predicting a weight difference between an actual boom weight and a designed boom weight based on each variation calculated by the variation calculating means 207 at the first angle or the second angle. Means 210 and, based on the predicted weight difference, determine the amount of deviation between the actual measured value of the hoist rope tension and the designed theoretical value due to the difference between the actual boom weight and the designed boom weight to the boom hoist angle. And a tension deviation calculating means 211 for calculating the displacement. According to a fifth aspect of the present invention, in the crane load calculating device according to the fourth aspect, the deviation amount of the hoisting rope tension calculated by the first angle deviation calculating unit 208 and the second angle deviation calculating unit 209 are used. The difference between the calculated deviation amount of the undulating rope tension and the difference between the variance amount of the undulating rope tension at the first angle and the variation amount of the undulating rope tension at the second angle calculated by the change amount calculating means 207. The weight shift prediction means 210 is configured to predict the weight difference between the actual boom weight and the designed boom weight based on the ratio of

According to a sixth aspect of the present invention, there is provided a boom angle detecting means 301 for detecting a boom up / down angle, a jib angle detecting means 302 for detecting a jib up / down angle connected to a boom tip, and a boom up / down operation. Load detecting means 303 for detecting the hoisting rope tension acting on the hoisting rope, and actual hoisting load calculating means 304 for calculating the actual load of the hoisting load based on the detected boom hoisting angle, jib hoisting angle and hoisting rope tension. Is applied to the load calculation device of a crane equipped with a crane, and calculates the deviation between the actual measured value of the hoisting rope tension and the theoretical design value due to the difference between the actual jib weight and boom weight and the designed jib weight and boom weight. Jib hoisting angle and boom hoisting included in the hoisting rope tension detected by the hoisting rope tension deviation calculating means 305 to be calculated and the load detecting means 303. A load detection error calculating unit 306 for calculating the load detection error which is an error amount which does not depend on time, and shift amount of hoist cable tension calculated by the hoisting rope tension deviation calculating means 305, load detection error calculating unit 306
Correction amount calculating means 307 for calculating a correction amount of the undulating rope tension detected by the load detecting means 303 based on the error amount calculated by the load calculating means 303, and calculates the actual load of the suspended load based on the correction amount. As shown in FIG.
04. The invention according to claim 7 is
7. The crane load calculating device according to claim 6, wherein the first change is calculated in accordance with the jib hoisting angle, when the actual jib weight is heavier or lighter by a predetermined weight than a predetermined weight. An amount calculating means 308;
A second change amount calculating means 309 for calculating a change amount of the hoisting rope tension when the actual boom weight is heavier or lighter than a predetermined weight by a predetermined weight according to the boom hoisting angle; On the basis of the amount of change in the undulation rope tension calculated by 308 and the amount of change in the undulation rope tension calculated by the second change amount calculation unit 309,
The difference between the actual measured value of the hoist rope tension and the theoretical design value due to the weight difference between the actual jib weight and boom weight and the designed jib weight and boom weight is determined according to the boom hoist angle and the jib hoist angle. The lifting rope tension deviation calculating means 305 is configured to perform the calculation. According to an eighth aspect of the present invention, in the load calculating device for a crane according to the seventh aspect, the load detecting means 303 is provided when the boom hoisting angle is the first angle and the jib hoisting angle is the second angle.
Angle deviation calculating means 310 for calculating the amount of deviation between the actually measured value of the up-and-down rope tension detected by the above and the theoretical value in design.
The boom angle is the first angle and the jib angle is the third angle.
A second angle shift calculating means 309 for calculating a shift amount between the actually measured value of the hoisting rope tension detected by the load detecting means 303 and a theoretical value at design at the angle of; When the jib undulation angle is the fifth angle,
A third angle shift calculating means for calculating a shift amount between a measured value of the undulating rope tension detected by the load detecting means and a theoretical value in design;
10. When the amount of deviation of each hoisting rope tension calculated by the second angle shift calculating means 309 and the third angle shift calculating means 312 and the jib hoist angle is the second angle, the third angle or the fifth angle Based on each change amount calculated by the first change amount calculation means 308 and each change amount calculated by the second change amount calculation means 309 when the boom undulation angle is the first angle or the fourth angle. The deviation between the actual measured value of the hoisting rope tension and the theoretical design value due to the difference between the actual boom weight and the designed boom weight is calculated according to the boom hoisting angle and the jib hoisting angle. It constitutes rope tension deviation calculating means 305. According to a ninth aspect of the present invention, in the load calculating device for a crane according to the eighth aspect, the first angle shift calculating means 310 and the second angle shift calculating means
The difference between the amount of deviation of each hoisting rope tension calculated by the angle deviation calculating means 309 and the amount of change calculated by the first change amount calculating means 308 when the jib hoisting angle is the second angle or the third angle. Based on the above, the jib own weight deviation prediction means 313 for predicting the weight difference between the actual jib weight and the designed jib weight, and the respective values calculated by the second angle deviation calculation means 309 and the third angle deviation calculation means 312 The difference between the amount of deviation of the hoisting rope tension, the difference between the amounts of change calculated by the second change amount calculating means 309 when the boom hoisting angle is the first angle or the fourth angle, and the prediction by the jib own weight shift predicting means 313. Based on the calculated weight difference, the boom weight shift prediction means 314 for predicting the weight difference between the actual boom weight and the designed boom weight, and the boom weight shift prediction means 314. Based on the predicted weight difference, the amount of deviation between the measured value of the hoist rope tension and the theoretical design value due to the difference between the actual boom weight and the designed boom weight is calculated based on the boom hoist angle and the jib hoist. And a tension deviation calculating means 315 for calculating according to the angle. According to a tenth aspect of the present invention, in the crane load calculating device according to the ninth aspect, the actual jib weight and design when the boom hoist angle is the first angle and the jib hoist angle is the third angle. The third jib for calculating the amount of deviation between the measured value of the undulating rope tension and the theoretical value in design due to the difference from the above jib weight.
The angle tension deviation calculating means 316 and the boom undulation angle are the fourth
When the jib hoisting angle is the fifth angle at the angle, the deviation amount between the actually measured value of the hoisting rope tension and the designed theoretical value due to the difference between the actual jib weight and the designed jib weight is calculated. And a jib fifth angle-tension deviation calculating means 317, and the difference between the amount of deviation of the up-and-down rope tension calculated by the first angle-displacement calculating means 310 and the amount of deviation of the up-and-down rope tension calculated by the second angle-delay calculating means 309. Based on the ratio between the difference and the difference between the amounts of change calculated by the first change amount calculating means 308 when the jib undulation angle is the third angle or the fifth angle, the actual jib weight and the design The jib own weight deviation estimating means 313 is configured to predict the weight difference from the jib weight, and is calculated by the jib second angle tension deviation estimating means from the deviation amount of the hoist rope tension computed by the second angle deviation computing means 309. The shift amount is subtracted, the result of the third
From the deviation amount of the undulation rope tension calculated by the angle deviation calculating means 312, the jib fifth angle tension deviation calculating means 317 is used.
The difference between the result of subtracting the shift amount calculated by
The actual boom weight and the designed boom weight are calculated based on the ratio of the difference between the amounts of change calculated by the second change amount calculating means 309 when the boom angle is the first angle or the fourth angle. The boom own weight deviation estimating means 314 is configured to predict the weight difference of the boom.

[0012]

According to the first aspect of the present invention, the amount of deviation between the actual measured value of the hoisting rope tension and the designed theoretical value due to the difference between the actual boom weight and the designed boom weight is determined by the deviation of the hoisting rope tension. The calculation is performed by the calculation means 204. Further, the load detection error calculating means 205 calculates an error of the load detecting means itself, which is an error amount included in the hoisting rope tension detected by the load detecting means 202 and independent of the boom hoisting angle. Then, the correction amount calculating means 206 calculates the shift amount calculated by the up-and-down rope tension shift calculating means 204,
Based on the error amount calculated by the load detection error calculation means 205, the correction amount of the undulation rope tension detected by the load detection means 202 is calculated, and based on this correction amount, the actual suspension load calculation means 203 Calculate the actual load of the load. According to the second aspect of the present invention, when the actual boom weight is heavier or lighter by a predetermined weight than a predetermined weight, a change amount of the hoisting rope tension is calculated by the change amount calculating means 207, and based on this change amount, The hoisting rope tension deviation calculating means 204 calculates the amount of deviation between the measured value of the hoisting rope tension and the theoretical value in design according to the boom hoisting angle. According to the third aspect of the present invention, when the boom hoisting angle is the first angle, the amount of deviation between the actually measured value of the hoisting rope tension detected by the load detecting means 202 and the theoretical value in design is determined by the first angle deviation. The calculation is performed by the calculation means 208. Further, when the boom hoisting angle is the second angle, the amount of deviation between the measured value of the hoisting rope tension detected by the load detecting means 202 and the theoretical value in design is calculated by the second angle deviation calculating means 209. Then, the lifting rope tension deviation calculating means 204
The deviation amounts of the undulation rope tensions calculated by the first angle deviation calculating means 208 and the second angle deviation calculating means 209 and the deviation amounts calculated by the change amount calculating means 207 at the first angle or the second angle. Based on the amount of change, the amount of deviation between the actually measured value of the hoisting rope tension and the theoretical value in design is calculated according to the boom hoisting angle. The lifting rope tension deviation calculating means 204 according to the fourth aspect of the present invention includes a weight deviation predicting means 210 and a tension deviation calculating means 211. First, the weight deviation predicting means 210 includes a first angle deviation calculating means 208 and a second angle deviation calculating means. The actual boom weight is calculated based on the amount of deviation of each hoist rope tension calculated by the deviation calculating means 209 and the amount of change calculated by the change amount calculating means 207 at the first angle or the second angle. And the weight difference between the design boom weight. Then, based on the predicted weight difference, the tension deviation calculating means 211 calculates a deviation between the actually measured value of the up-and-down rope tension caused by the difference between the actual boom weight and the designed boom weight and the designed theoretical value. The quantity is calculated according to the boom angle. The weight shift predicting means 210 according to the fifth aspect of the present invention includes the first angle shift calculating means 20.
8 and the difference between the amount of deviation of the hoisting rope tension calculated by the second angle deviation calculating means 209 and the amount of deviation at the first angle calculated by the change amount calculating means 207. A weight difference between an actual boom weight and a designed boom weight is predicted based on a ratio of a change amount of the rope tension and a difference between a change amount of the hoisting rope tension at the second angle.

In the invention according to claim 6, the deviation amount between the actually measured value of the hoisting rope tension and the theoretical value in design is calculated by the hoisting rope tension deviation calculating means 305. The load detection error calculation means 306 calculates a load detection error, which is an error amount independent of the jib hoist angle and the boom hoist angle, included in the hoisting rope tension detected by the load detecting means 303. Then, the correction amount calculating means 307 calculates the deviation amount of the hoisting rope tension calculated by the hoisting rope tension deviation calculating means 305 and the load detection error calculating means 306.
A correction amount of the hoisting rope tension detected by the load detection unit 303 is calculated based on the error amount calculated by the load detection unit 303, and the actual suspension load calculation unit 304 is calculated based on the correction amount.
Calculates the actual load of the suspended load. According to the seventh aspect of the present invention, when the actual jib weight is heavier or lighter than a predetermined weight by a predetermined weight, the change amount of the hoist rope tension is calculated by the first change amount calculating means 308 according to the jib hoist angle. In the case where the actual boom weight is heavier or lighter than a predetermined weight by a predetermined weight, the amount of change in the undulating rope tension
The change amount is calculated by the change amount calculation means 309 according to the boom undulation angle. Then, the lifting rope tension deviation calculating means 305
The actual measured value and the design value of the undulation rope tension are calculated based on the change amount of the undulation rope tension calculated by the first change amount calculation unit 308 and the change amount of the undulation rope tension calculated by the second change amount calculation unit 309. The amount of deviation from the above theoretical value is calculated according to the boom undulation angle and the jib undulation angle. In the invention described in claim 8, the amount of deviation between the measured value of the hoisting rope tension and the theoretical design value when the boom hoisting angle is the first angle and the jib hoisting angle is the second angle is determined by the first angle deviation. The calculating means 310 calculates the difference between the actually measured value of the hoisting rope tension and the theoretical design value when the boom hoisting angle is the first angle and the jib hoisting angle is the third angle. 309, and the third angle deviation calculating means 312 calculates the amount of deviation between the actually measured value of the hoist rope tension and the designed theoretical value when the boom angle is the fourth angle and the jib angle is the fifth angle. Calculate. Then, the up-and-down rope tension deviation calculating means 305 is provided with the first angle deviation calculating means 31.
0, when the deviation amount of each hoisting rope tension calculated by the second angle deviation calculating means 309 and the third angle deviation calculating means 312 and the jib hoisting angle is the second angle, the third angle or the fifth angle Based on each change amount calculated by the first change amount calculation means 308 and each change amount calculated by the second change amount calculation means 309 when the boom undulation angle is the first angle or the fourth angle. Then, the deviation between the measured value of the hoisting rope tension and the theoretical value in design is calculated according to the boom hoisting angle and the jib hoisting angle. The lifting rope tension deviation calculating means 305 according to the ninth aspect includes a jib own weight deviation estimating means 313, a boom own weight deviation estimating means 314, and a tension deviation calculating means 315, and the jib own weight deviation estimating means 313 comprises: The deviation amount of each hoist rope tension calculated by the angle deviation calculating means 310 and the second angle deviation calculating means 309 and the jib hoisting angle are the second angle or the third angle.
The weight difference between the actual jib weight and the designed jib weight is predicted on the basis of the difference between the amounts of change calculated by the first change amount calculating means 308 at the angle of. In addition, the boom own-weight shift estimating means 314 includes the second angle shift calculating means 30.
9 and the deviation amount of each hoisting rope tension calculated by the third angle deviation calculating means 312 and the boom hoisting angle
The second change amount calculating means 3 when the angle is the fourth angle or the fourth angle.
The weight difference between the actual boom weight and the designed boom weight is predicted on the basis of the difference between the amounts of change calculated in step 09 and the weight difference predicted by the jib own weight deviation prediction unit 313. Then, based on the weight difference predicted by the boom own-weight deviation prediction unit 314, the tension deviation prediction unit calculates a deviation amount between the measured value of the hoisting rope tension and the theoretical value in design according to the boom hoisting angle and the jib hoisting angle. To calculate. According to the tenth aspect, when the boom hoisting angle is the first angle and the jib hoisting angle is the third angle, the deviation between the measured value of the hoisting rope tension and the theoretical value in design is determined by the third jib. Angular tension deviation calculating means 316 calculates the deviation between the measured value of the hoist rope tension and the theoretical value in design when the boom hoist angle is the fourth angle and the jib hoist angle is the fifth angle. The calculation is performed by the five-angle tension deviation calculating means 317. Then, the jib own weight deviation prediction means 313
The difference between the amount of deviation of the hoisting rope tension calculated by the angle deviation calculating means 310 and the amount of deviation of the hoisting rope tension calculated by the second angle deviation calculating means 309, and the jib hoisting angle is the second angle or the third angle The weight difference between the actual jib weight and the designed jib weight is predicted based on the ratio of the difference between the amounts of change calculated by the first change amount calculating means 308 at the angle. In addition, the boom own weight deviation prediction means 31
4 subtracts the amount of deviation calculated by the jib second angle tension deviation prediction means from the amount of deviation of the hoisting rope tension computed by the second angle deviation computation means 309, and the result is subtracted by the third angle deviation computation means 312. The jib third angle tension deviation calculating means 31 is calculated from the calculated deviation amount of the undulating rope tension.
6 and the difference between the amounts of change calculated by the second change amount calculating means 309 when the boom undulation angle is the first angle or the fourth angle. Based on the ratio, predict the weight difference between the actual boom weight and the designed boom weight.

[0014]

【Example】

First Embodiment Hereinafter, a first embodiment in which the load calculation device according to the present invention is applied to a crane will be described with reference to FIGS. FIG. 4 is an external view of the crane. 1 is a lower traveling body of the crane, 2 is an upper revolving body pivotally connected to the upper part of the lower traveling body 1,
Reference numeral 3 denotes a boom connected to the front part of the upper swing body 2 so as to be able to undulate. This boom 3 is composed of a basic boom 3a and a joint boom 3
b, the joint boom 3b is detachable, and a plurality of joint booms 3b are connectable to the basic boom 3a. Reference numeral 4 denotes a hoisting winch for controlling lifting and lowering of a suspended load, and reference numeral 5 denotes an hoisting winch for controlling the undulation of the boom 3. Both the hoisting winch 4 and the hoisting winch 5 are disposed substantially at the center of the upper swing body 2. The hoisting rope 6 unreeled from the hoisting winch 4 is
The hanging load 9 attached to the hook 8 moves up and down in response to the rotation of the hoisting winch 4 via the pulleys 18 and 7 attached to the tip of the hook 8. Undulating rope 1 unreeled from an unwinding winch 5
0 is a hanger 1 attached to the tip of the mast 11
2 and bridle 13
One end of 3 is connected to the tip of the boom 3 by a pendant rope. 14 is attached to the hanger 12,
A load detector 15 for detecting the tension of the hoisting rope 10 is an angle detector attached to the base end of the boom 3 to detect the hoisting angle of the boom 3.

FIG. 3 shows a first example of a load calculating device according to the present invention.
FIG. 4 is a block diagram of an embodiment of FIG. This load calculating device is provided, for example, inside the upper swing body 2. Reference numeral 101 denotes an operation comparing unit, in which an operation unit 101a for calculating the actual load of the suspended load 9 based on the processing of FIGS.
And a comparing unit 101b for determining whether or not an overload occurs. Reference numeral 102 denotes a first storage unit that stores the boom hoisting angle detected by the angle detector 15 and the hoisting rope tension detected by the load detector 14.
M. Reference numeral 103 denotes a second storage unit that stores a theoretical value of the design of the hoisting rope tension based on a preset boom weight in accordance with the boom hoisting angle. That is, the second storage unit 103 stores the hoisting rope tension based on the boom weight which is determined in advance in consideration of the crane design conditions and the like according to the boom hoisting angle. This second
Is configured by, for example, a ROM.
A switching unit 104 switches between connecting the load detector 14 and the calculation unit 101a or connecting the load detector 14 and the first storage unit 102. 105 is an arithmetic unit 101a
A display unit 106 that displays the actual load calculated by the above and the boom undulation angle detected by the angle detector 15 is an alarm device that issues an alarm when the comparing unit 101b determines that an overload has occurred.

FIGS. 5 and 6 show the operation unit 101a of the first embodiment.
Is a flowchart showing the operation of the first embodiment. The operation of the first embodiment will be described based on this flowchart. First,
The boom 3 is raised in a state where the hanging load 9 is not attached to the hook 8 (hereinafter, no load state). In step S1 of FIG. 5, the boom undulation angle detected by the angle detector 15 is read, and when the boom undulation angle becomes θ1, the boom 3
To stop the undulating operation. This angle θ1 is stored in the first storage unit 102. In step S2, the switch 104
The load detector 14 is connected to the first storage unit 102 by sending a signal to the first storage unit 102, and the boom undulation rope tension _Ta01 detected by the load detector 14 is stored in the first storage unit 102. _{Read a01} .

In step S3, the theoretical value T _s01 of the design of the _hoisting rope tension at the boom _hoisting angle θ1 is read from the second storage unit 103. In step S4, (2) as shown in the expression for calculating the deviation Def ₁ between the theoretical value T _s01 of the design and measured values T _a01.

Def ₁ = T _s01 −T _a01 (2) In this case, only the boom weight is applied to the _hoisting rope 10, while the load detector 14 has a zero point shift. The expression Def ₁ includes the two types of shifts shown in the expression (3).

Def ₁ = (displacement of undulation tension due to boom weight at angle θ1) + (zero point displacement of load detector) (3)

Next, in step S5, the boom angle is changed, and the boom angle θ2 detected by the angle detector 15 is read. In step S6, the undulating rope tension _Ta02 in this working posture is read from the load detector 14.
The boom hoist angle θ2 and the hoist rope tension _Ta02 are stored in the first storage unit 102. In step S7, the theoretical theoretical value _Ts02 of the _hoist rope tension at the boom _hoist angle θ2 is read from the second storage unit 103. Step S
8, as shown in equation (4), the theoretical value T _{s02 in} design is _obtained.
And calculating a deviation Def ₂ measured value T _a02.

Def ₂ = T _s02 −T _a02 (4) Def _{2 in} equation (4) includes two types of shifts shown in equation (5).

Def ₂ = (deviation of undulation tension due to boom weight at angle θ2) + (zero displacement of load detector) (5)

Next, in step S9, as shown in equation (6), the difference between equations (2) and (4) is calculated.

ΔDef ₁₂ = Def ₁ −Def ₂ (6) Since the zero point shift of the load detector 14 is constant irrespective of the boom angle, the calculation of the equation (6) is performed. The zero point shifts of the load detector 14 cancel each other.
That is, (6) DerutaDef ₁₂ of includes a shift shown in equation (7).

ΔDef ₁₂ = (shift of the hoisting tension due to boom weight at angle θ1) − (shift of the hoisting tension due to boom weight at angle θ2) (7)

Next, in step S10 shown in FIG.
As shown in the equation (8), a difference between the boom weight correction sensitivity K _b1 at the boom hoist angle θ1 and the boom weight correction sensitivity K _b2 at the boom hoist angle θ2 is obtained.

Equation 8] _{ΔK b12 = K b1 -K b2 ···} (8) Here, the boom weight correction sensitivity K _b, and the no-load hoist cable tension when the boom 3 was weight a predetermined boom 3 is the difference from the no-load hoisting rope tension when the weight differs by a predetermined weight from a predetermined weight.

FIG. 7 is a diagram showing the relationship between the boom derricking angle and boom weight correction sensitivity curve a in FIG. 7 is a predetermined weight W _b only heavy when boom weight correction than boom weight boom 3 predetermined Indicates sensitivity. In FIG. 7, the boom weight correction sensitivity corresponding to the boom undulation angle θ1 on the curve a is represented by K _b1.
And then, a boom weight correction sensitivity corresponding to the boom derricking angle θ2 and K _b2, show the difference DerutaKb ₁₂ obtained in step S10 in the illustrated arrows. The difference [Delta] K _b12 indicates if W _b heavier than the weight of the boom weight is determined in advance, the difference between the deviation of the hoist cable tension at the deviation and the boom derricking angle θ2 of hoist cable tension at the boom derricking angle .theta.1. on the other hand,
Boom weight correction sensitivity when more W _b heavier than a predetermined weight W _b actual boom weight indicated by the curve a is shown by the curve b in FIG. In FIG. 7, the boom undulation angle θ on the curve b
The boom weight correction sensitivity corresponding to 1 is _Kb3, and the boom weight correction sensitivity corresponding to the boom undulation angle θ2 is _Kb4 . In FIG. 7, K _b3 = 2 × K _b1 , K _b4 = 2 × K _b2
Therefore , ΔK _b34 = K _b3 −K _b4 = 2 × K _b1 −2 × K
_b2 = 2 × [Delta] K _b12 becomes, [Delta] K _b34 curve b is twice the curves a [Delta] K _b12. That is, if the difference between the actual boom weight and the predetermined boom weight is doubled, the difference obtained by the equation (8) is also doubled. in this way,
By calculating the difference between the boom weight correction sensitivities according to the equation (8), it is possible to grasp how much the actual boom weight differs from the predetermined boom weight. Note that the relationship in FIG. 7 may be obtained by a calculated value or may be obtained based on an actually measured value.

Next, in step S11, obtains the boom weight correction coefficient BP _def based on equation (9).

BP _def = ΔDef ₁₂ / ΔK _b12 (9) The boom weight correction coefficient BP _def indicates how much the actual boom weight deviates from a predetermined boom weight. In addition, this deviation amount is determined by a predetermined weight W
It is expressed as a ratio to _b . By multiplying the boom weight correction coefficient BP _def by the boom weight correction sensitivity _Kb , the amount of deviation of the hoist rope tension due to the boom weight according to the boom hoist angle is obtained. For example, in order to determine the deviation amount of the hoist rope tension due to the boom weight at the boom hoist angle θ1, the BP _def may be multiplied by the boom weight correction sensitivity K _b1 at the boom hoist angle θ1.

Next, in step S12, the zero point shift C _def of the load detector 14 is obtained using the equations (2) and (9) or the equations (4) and (9). The expression in this case is as shown in Expression (10) or Expression (11).

C _def = Def ₁ −BP _def × K _b1 (10) C _def = Def ₂ −BP _def × K _b2 (11)

Next, in step S13, the boom is raised with the actual suspended load attached to the hook, the boom undulation angle is set to an angle corresponding to the work, and the load correction amount DW in this work posture is set to ( 12) Calculate based on equation.

DW = C _def + BP _def × K _b (12) When performing the calculation of the equation (12), the zero point shift C _def uses the value calculated in step S12, and the boom weight correction coefficient B
P _def uses the value calculated in step S11. Also,
As the boom weight correction sensitivity _Kb , the self-weight correction sensitivity _Kb corresponding to the current boom undulation angle is read from the second storage unit 103. If the self-weight correction sensitivity of the corresponding boom undulation angle is not stored in the second storage unit 103, the weight may be obtained by approximation means such as proportional interpolation using the self-weight correction sensitivity of an angle close to the angle. .

Next, in step S14, the actual load W of the suspended load is obtained based on the equation (13).

(Equation 12) Here, T _L is hoist cable tension in a state of hanging the actual suspended load, T ₀ is hoist cable tension when hoisting rope tension by boom weight, T ₂ is that hanging a predetermined known weight of the suspended load, W _C indicates a predetermined known weight value.

Next, in step S15, step S1
It is determined whether or not the actual load W obtained in 4 is larger than the rated total load corresponding to the current boom angle, and if it is larger, a signal is sent to the alarm device 106 to give an alarm. Thereafter, when the boom hoisting angle is changed, steps S13 to S13 are executed.
15 is performed.

The operation of the first embodiment is summarized as follows.
By changing the boom hoisting angle in two ways and comparing the hoisting rope tension at each angle, the shift amount BP _def × K _b of the hoisting rope tension due to the boom weight and the zero point shift C _def of the load detector 14 are calculated. Ask. Then, the correction amount DW is obtained using these deviation amounts, and the actual load W is obtained based on the equation (13).

As described above, according to the first embodiment, even if the boom weight is different from the theoretical value in design, the actual load of the suspended load according to the boom undulation angle can be calculated with high accuracy. Further, since the correction amount DW for correcting the conventional actual load calculation formula can be calculated only by changing the boom hoisting angle in two ways, a highly accurate actual load can be obtained easily and quickly.

-Second Embodiment- A second embodiment shows an example in which the load calculation device according to the present invention is applied to a tower crane. FIG. 8 is an external view of the tower crane. 51 is a lower traveling body of the tower crane, 52
Reference numeral 53 denotes an upper revolving structure that is pivotally connected to an upper portion of the lower traveling structure 51, and 53 denotes a tower boom that is rotatably connected to a front portion of the upper revolving structure 52. The tower boom 53 includes a basic boom 53a and a joint boom 53b, and the joint boom 53b is detachable.
Can be simultaneously connected to the basic boom 53a. At the tip of the tower boom 53, a tower jib 54 and a triangular swing lever 55 are respectively swingably attached. A corner of the triangular swing lever 55 is connected to a tip of the tower jib 54 by a pendant rope 56. The tower jib 54 includes a basic jib 54a and a joint jib 54b. The joint jib 54b is detachable.
a.

Reference numeral 57 denotes a hoisting winch for controlling lifting and lowering of a suspended load; 58, a tower boom hoisting winch for controlling the hoisting of the tower boom 53; 59, a tower jib hoisting winch for controlling the hoisting of the tower jib 54; Both the boom hoisting winch 58 and the tower jib hoisting winch 59 are disposed substantially at the center of the upper swing body 52. The hoisting rope 60 extended from the hoisting winch 57 is connected to the tower boom 53.
Pulley 61 and tower jib 5 attached to the tip of
The hook 64 is wound around a pulley 64 a of a hook 64 via pulleys 62 and 63 attached to the tip of the hook 4.
The lifting load 65 attached to the upper and lower sides rises and falls according to the rotation of the hoisting winch 57.

A boom hoisting rope 66 extended from the tower boom hoisting winch 58 is hung around a tower boom hanger 68 and a tower boom bridle 69 attached to the end of a mast 67. One end of the tower boom bridle 69 is It is connected to the tip of the tower boom 53 by a pendant rope. The jib hoisting rope 70 extended from the tower jib hoisting winch 59 is
The tower jib hanger 71 and the tower jib bridle 72 are hung around. One end of the tower jib bridle 72 is connected to a triangular swing lever 55 by a pendant rope.
Connected to the corners of 14 is a load detector that is attached to the tower boom hanger 68 and detects the tension of the boom hoisting rope 66; 15A is an angle detector that is attached to the base end of the tower boom 53 and detects the hoisting angle of the tower boom 53; An angle detector 15B is attached to the base end of the tower jib 54 and detects the undulation angle of the tower jib 54.

FIG. 9 is a block diagram of a second embodiment of the load calculating device according to the present invention. The load calculating device in FIG.
3 except that the angle detectors 15A and 15B are connected to the first storage unit 102 and the second storage unit 103, respectively. Is omitted.

FIGS. 10 and 11 show the operation unit 10 of the second embodiment.
5 is a flowchart showing the operation of the first embodiment, and the operation of the second embodiment will be described based on the flowchart. First, the tower boom 53 and the tower jib 54 are erected with no load. In step S101 of FIG. 10, the tower boom undulation angle and the tower jib undulation angle detected by the angle detectors 15A and 15B are read, and when the tower boom undulation angle becomes θ _T1 and the tower jib undulation angle becomes θ _J1 , the undulating operation is performed. To stop. In step S102, the boom hoist rope tension _Ta11 detected by the load detector 14 is read. Note that the tower boom hoist angle θ _T1 , the tower jib hoist angle θ _J1, and the boom hoist rope tension T _a11 are stored in the first storage unit 102.

In step S103, the designed theoretical value T _s11 of the boom hoist rope tension at the tower jib hoist angle θ _J1 at the tower boom hoist angle θ _T1 is read from the second storage unit 103. In step S104, as shown in equation (14), the deviation De between the actually measured value _Ta11 and the designed theoretical value _Ts11 is De.
determine the f _10.

Def ₁₀ = T _s11 -T _a11 (14) In this case, only the tower boom weight and the tower jib weight are applied to the boom hoisting rope 66, while the load detector 14 has a zero point shift. Therefore, Def _{10 in} equation (14)
Contains three types of shifts as shown in equation (15).

Equation 14] Def ₁₀ = (deviation of the tower boom weight due relief tension at an angle theta _T1) + (the angle theta _T1, the deviation of the relief tension by Tawajibu weight in theta _J1) + (zero point deviation of the load detector) ... (15)

Next, in step S105, the tower jib undulation angle is changed without changing the tower boom undulation angle.
The tower boom up / down angle θ _T1 and the tower jib up / down angle θ _J2 detected by the angle detectors 15A and 15B are read. In step S106, the boom hoist rope tension _Ta12 in this working posture is read from the load detector 14. The tower boom undulation angle θ _T1 and the tower jib undulation angle θ
_J2 and the boom hoist rope tension _Ta12 are stored in the first storage unit 102.

In step S107, the designed theoretical value _Ts12 of the boom hoisting rope tension in this working posture is read from the second storage unit 103. In step S108,
(16) As shown in equation determines the deviation Def ₂₀ Calculated T _s12 and the measured values T _a12.

Def ₂₀ = T _s12 −T _a12 (16) The Def ₂₀ obtained by the equation (16) includes three types of shifts as shown in the equation (17).

Equation 16] Def ₂₀ = (deviation of the tower boom weight due relief tension at an angle theta _T1) + (the angle theta _T1, the deviation of the relief tension by Tawajibu weight in theta _J2) + (zero point deviation of the load detector) ... (17)

Next, in step S109, the tower boom up / down angle and the tower jib up / down angle are changed, and the tower boom up / down angle θ _T2 and the tower jib up / down angle θ _J3 detected by the angle detectors 15A and 15B are read. In step S110, the boom hoist rope tension _Ta13 in this working posture is read from the load detector 14. The tower boom hoisting angle θ _T2 , tower jib hoisting angle θ _J3, and boom hoisting rope tension T _a13 are stored in the first storage unit 102.
Is stored.

In step S111, the designed theoretical value _Ts13 of the boom hoisting rope tension in this working posture is read from the second storage unit 103. In step S112,
(18) As shown in equation determines the deviation Def ₃₀ Calculated T _s13 and the measured values T _a13.

Def ₃₀ = T _s13 −T _a13 (18) The Def ₃₀ obtained by the equation (18) includes three kinds of shifts as shown in the equation (19).

Equation 18] Def ₃₀ = (deviation of undulations tension by tower boom weight at an angle theta _T2) + (the angle theta _T2, the deviation of the relief tension by Tawajibu weight in theta _J3) + (zero point deviation of the load detector) ... (19)

Next, in step S113 of FIG.
As shown in equation (20), the D obtained in step S104
A difference ΔDef ₁₀₂₀ between ef ₁₀ and Def ₂₀ obtained in step S108 is obtained.

(19) ΔDef ₁₀₂₀ = Def ₁₀ −Def ₂₀ (20) Since the zero point shift of the load detector 14 is equal between Def ₁₀ and Def ₂₀ , they are offset by the subtraction of the expression (20). Also, the deviation of the undulating rope tension due to the tower boom weight is equal in Def ₁₀ and Def ₂₀ and is offset each other,
Eventually, ΔDef ₁₀₂₀ includes the deviation shown in Expression (21).

ΔDef ₁₀₂₀ = (shift of undulation tension due to tower jib weight at θ _T1 , θ _J1 ) − (shift of undulation tension due to tower jib weight at θ _T1 , θ _J2 ) (21)

Next, in step S114, as shown in the equation (22), the tower jib up / down angle θ _T1 , the tower jib weight correction sensitivity K _Jb1 at the tower _{jib up /} down angle θ _J1 , the tower boom up / down angle θ _T1 , and the tower jib up / down angle The difference ΔK _Jb12 from the _tower jib weight correction sensitivity K _Jb2 at θ _J2 is determined.

ΔK _Jb12 = K _Jb1 −K _Jb2 (22) Here, the tower jib weight correction sensitivity is the tower jib 54.
Is a predetermined weight, and a difference between the no-load hoisting rope tension when the tower jib 54 differs from the predetermined weight by a predetermined weight.

FIG. 12 is a diagram showing the relationship between the tower jib undulation angle θ _J and the tower jib weight correction sensitivity K _Jb . The curves shown in FIG. 12 are obtained when the tower jib 54 is heavier than a predetermined weight by a predetermined weight. 11 shows tower jib weight correction sensitivity. As shown, it draws different curves in accordance with the tower boom derricking angle theta _T. FIG. 10 shows respective curves when the tower boom hoisting angle θ _T is θ _T1 , θ _T2 , and θ _T3 . The ΔK _Jb12 by the equation (22) is indicated by an arrow in the drawing, and the ΔK _Jb12 is the tower jib hoisting angle θ _J1 when the weight of the tower jib 54 is heavier than a predetermined weight by W _JC.
The difference between the tower jib up-and-down rope tension deviation at t and the tower jib up-down rope tension deviation at the tower jib up-down angle θ _J2 is shown.

[0042] Then in step S115, based on the (23) equation, to calculate the Tawajibu weight correction factor TJP _def.

TJP _def = ΔDef ₁₀₂₀ / ΔK _b12 (23) The tower jib weight correction coefficient TJP _def indicates how much the tower jib weight deviates from the theoretical value in design. 9 shows a deviation amount from a theoretical value in design as a ratio to a predetermined weight W _JC . By multiplying the TJP _def obtained by equation (23) by the tower jib weight correction sensitivity K _Jb , the deviation of the boom hoist rope tension due to the tower jib weight is obtained.

Next, in step S116, (24),
The coefficients Def ₂₀ ′ and Def ₃₀ ′ are obtained based on the equation (25).

Def ′ ₂₀ = Def ₂₀ −TJP _def × K _Jb2 (24) Def ′ ₃₀ = Def ₃₀ −TJP _def × K _Jb3 (25) The Def ′ ₂₀ and Def ′ ₃₀ are (26),
Equation (27) is included. Def _'20 = (tower boom weight due to the deviation of the relief tension at an angle theta _T1) + (zero point of the load detector _{shift) ··· (26) Def' 30} = ( relief by tower boom weight at an angle theta _T2 Tension deviation) + (Zero point deviation of load detector) ... (27)

Next, in step S117, the as shown in (28), Def _'20 and Def'3 ₀ difference ΔDe
Find _f'2030 .

ΔDef ′ ₂₀₃₀ = Def ′ ₂₀ −Def ′ ₃₀ (28) When the calculation of the expression (28) is performed, the zero point shift of the load detector 14 is canceled out, so that ΔDef ′ ₂₀₃₀ becomes ( 29) includes the deviation shown in the equation.

ΔDef ′ ₂₀₃₀ = (displacement of undulation tension due to tower boom weight at angle θ _T1 ) − (displacement of undulation tension due to tower boom weight at angle θ _T2 ) (29)

Next, in step S118, (30) as shown in equation a tower boom weight correction sensitivity K _Tb1 in tower boom derricking angle theta _T1, the tower boom derricking angle theta _T2
ΔK _{Tb12 from} tower boom weight correction sensitivity K _{Tb2 at}
Ask for.

ΔK _Tb12 = K _Tb1 −K _Tb2 (30) Here, the tower boom weight correction sensitivity K _Tb is an unloaded undulating rope tension when the tower jib 54 has a predetermined weight. than the weight of Tawajibu 54 predetermined refers to the difference between the no-load hoist cable tension when different predetermined weight W _TC.

FIG. 13 is a diagram showing the relationship between the tower boom undulation angle θ _T and the tower boom weight correction sensitivity K _Tb .
Each of the illustrated curves shows the tower boom weight correction sensitivity when the tower boom 53 is heavier by a predetermined weight than a predetermined weight. ΔK _Tb12 obtained by Expression (30) is indicated by an arrow in the drawing. The [Delta] K _Tb12 is when heavy W _TC than weight the weight of the tower boom 53 is predetermined, and deviations of the hoist cable tension at the tower boom derricking angle .theta.1,
The difference with the deviation of the hoisting rope tension at the tower boom hoisting angle θ2 is shown.

Next, in step S119, based on the equation (31) obtains the tower boom weight correction factor TBP _def.

TBP _def = ΔDef ₂₀₃₀ '/ ΔK _Tb12 (31) The tower boom weight correction coefficient TBP _def indicates how much the weight of the tower boom 53 deviates from the theoretical value in design. The deviation amount is expressed as a ratio to a predetermined weight. Multiplying this tower boom weight correction factor TBP _def the tower boom weight correction sensitivity K _Tb, the deviation amount of relief tension by tower boom weight corresponding to the boom derricking angle is determined.

Next, in step S120, the zero point shift C _def of the load detector is calculated based on the equation (32) or (33).

Equation 28] _{C def = Def '20 -TBP def} × K Tb1 ··· (32) C def = Def' 30 -TBP def × K Tb2 ··· (33)

Next, in step S121, the tower boom 53 and the tower jib 54 are erected with the actual suspended load attached to the hook 64, and the tower boom undulation angle and the tower jib undulation angle are set to angles according to the work. The load correction amount DW in this working posture is calculated based on the equation (34).

DW = C _def + TJP _def × K _Jb + TBP _def × K _Tb (34)

Next, in step S122, step S
Using the load correction amount DW obtained in 121, the actual load W of the suspended load is obtained based on the equation (13), as in step S14 of FIG.

Next, in step S123, an alarm process is performed as in step S15 of FIG. Thereafter, when the boom angle is changed, steps S121 to S1 are performed.
Step 23 is performed.

The operation of the second embodiment is summarized as follows.
By changing the tower boom undulation angle and the tower jib undulation angle in three ways and comparing the tower boom undulation rope tension at each angle, the deviation amount TJP _def × K _{Jb due} to the tower jib weight and the deviation amount TBP due to the tower boom weight _def × K _Tb and zero point shift C of load detector 14
_{Ask def} . Then, the correction amount DW is obtained using these deviations, and the actual load is obtained based on the equation (13).

As described above, in the second embodiment, since the actual load is calculated in consideration of the deviation of the weight of each of the tower jib 54 and the tower boom 53 from the designed theoretical value, the actual load is accurately calculated. Can be calculated. In addition, the correction amount DW for correcting the conventional actual load calculation formula can be calculated only by changing the tower boom hoisting angle and the tower jib hoisting angle in three ways, so that the calculation time of the actual load can be reduced.

Third Embodiment In the first and second embodiments,
In determining the correction amount DW, the weight of the hook is not taken into account. However, in practice, the weight of the hook also affects the undulating rope tension. Further, the hook may be replaced depending on the work, and the replacement may change the hook weight. Therefore, in a third embodiment described below, the actual load calculation is performed in consideration of the hook weight.

FIG. 14 is a block diagram of a third embodiment in which the load calculating device is applied to the crane shown in FIG.
In this figure, the same components as those in the block diagram of the first embodiment shown in FIG. 3 are denoted by the same reference numerals, and the following description will focus on the differences. Reference numeral 201 in FIG. 14 denotes an input device for inputting the weight of the hook and instructing the storage of the rope tension.
The input device 201 is provided, for example, around the driver's seat, and when an operator inputs a hook weight, an actual load is calculated using the input value. On the other hand, when the worker instructs to store the undulation rope tension, the undulation rope tension output from the load detector 14 is stored in the first storage unit 102.

The load detector 14 and the angle detector 15 of the third embodiment are connected to an arithmetic unit 101a, unlike FIG. Therefore, the hoisting rope tension detected by the load detector 14 and the boom hoisting angle detected by the angle detector 15 are stored in the first storage unit 102 or the second storage unit 103 via the calculation unit 101a. You.

FIG. 15 is a flowchart showing the operation of the arithmetic unit 101a.
The operation of this embodiment will be described. First, the boom is raised with no load. In step S201 in FIG. 15, the boom undulation angle θ1 detected by the angle detector 15 is read.
In step S202, the hook weight input from the input device 201 is read. In step S203, the undulating rope tension _Ta21 in this working posture is read from the load detector 14. In step S204, the detected boom hoisting angle θ1 and the hoisting rope tension _Ta21 are stored in the first storage unit 102.
To memorize.

In step S205, the theoretical value T _s21 of the design of the hoisting rope tension in this working posture is read from the second storage unit 103. In step S206, (35)
As shown in equation, it calculates a difference Def ₁ between the actual measurement value T _a21 the theoretical value T _s21 of the design.

Def ₁ = T _s21 −T _a21 (35)

Here, the equation for calculating the actual load when the correction amount is not taken into consideration is shown by equation (1). When this equation (1) is modified, it becomes equation (36).

T _L = (T ₂ −T ₀ ) × W / W _C + T ₀ (36) T _L in the equation (36) is the undulation rope tension due to the boom weight and the undulation rope tension due to the hook weight. Is added. Therefore, the difference Def1 calculated by the expression (35) includes a deviation due to the hook weight in addition to the deviation shown in the expression (3).

Hereinafter, the actual load calculation can be performed in consideration of the hook weight by performing the processing after step S5 in FIG.

Fourth Embodiment In the third embodiment, the input device 201 is provided to set the boom undulation angle. However, the fourth embodiment described below is
The boom hoisting angle is set by a variable resistor instead of the input device 201. FIG. 16 is a block diagram of the fourth embodiment, in which components common to those of the first embodiment shown in FIG. 3 are denoted by the same reference numerals, and different points will be mainly described below. Reference numeral 301 in FIG. 16 denotes a variable resistor for matching the display on the display with the hook weight when the boom angle is θ1. Reference numeral 302 denotes a variable resistor for matching the display on the display 105 with the hook weight when the boom angle is θ2. These variable resistors 30
Each of the trimmers (not shown) is integrated with a trimmer (not shown).
The resistance values of 1,302 change.

Reference numeral 303 denotes a mode switch for switching between the adjustment mode and the work mode. The adjustment mode is a mode for obtaining the correction amount DW for calculating the actual load as described above, and the work mode is a mode set when performing a normal work. When the work mode is selected, the actual load is calculated using the correction amount DW calculated in the adjustment mode.

FIG. 17 is a flow chart showing the operation of the arithmetic unit according to the fourth embodiment. In step S301 of FIG. 17, it is determined whether or not the mode switch 303 is in the adjustment mode.
If the determination is affirmative, the process proceeds to step S302, in which the boom hoisting angle is set to θ1 in a no-load state, and the actual load is calculated based on equation (37). Note that the variable TR in equation (37)
M1 is a value determined by the resistance value of the variable resistor.

(Equation 32) In step S303, the actual load W calculated in step S302 is displayed on the display 105. Then, the operator turns the trimmer to change the resistance value of the variable resistor 301 so that the actual load W displayed on the display 105 matches the hook weight. Then, when they match, the resistance value TRM1 of the variable resistor 301 at that time is stored in the first storage unit 102. The value of this value TRM1 corresponds to Def ₁ calculated by equation (3). Step S3
In step 04, the boom angle is changed to θ2, and the actual load is calculated based on equation (38). Note that the resistance value TRM2 in the equation (38) is a value determined by the resistance value of the variable resistor 302.

[Equation 33]

In step S305, step S304
Is displayed on the display 105. The operator turns the trimmer to change the resistance value of the variable resistor 302 so that the actual load W displayed on the display 105 matches the hook weight. When they match, the resistance value TRM2 of the variable resistor 302 at that time is stored in the first storage unit. This value TRM2 corresponds to Def ₂ calculated by equation (5).

Thereafter, in steps S306 to S310,
The same processing as steps S9 to S13 in FIG. 5 is performed. That is, ΔDef ₁₂ , ΔKb ₁₂ , BP _def , and C _def are sequentially obtained.

Next, in step S310, it is determined whether or not the work mode has been set by the mode switch 303. If the determination is negative, the process remains at step S310. If the determination is affirmative, the process proceeds to step S311. On the other hand, when the determination in step S301 is denied, step S31 is also performed.
Proceed to 1. In step S311, the correction value DW is obtained based on the equation (12). Next, in step S312,
The actual load is calculated based on the equation (13).

As described above, in the fourth embodiment, the deviation of the hoisting rope tension due to the weight of the boom is detected by the variable resistor, so that the deviation can be made simpler and faster than in the first to third embodiments. And the calculation time of the actual load can be shortened.

In each of the above embodiments, the example in which the boom weight correction sensitivity is stored in the second storage unit 103 in advance has been described.
May be calculated based on equation (39) instead of storing in the storage unit 103.

K _b = (T ₂ −T ₀ ) / W _C (39) where W _{C in the} equation (39) is a rated total load, and T ₂ is a load of a weight equal to the rated total load. hoist cable tension if, T ₀ represents a hoist cable tension by boom weight at no load. In each of the above embodiments, the above T ₀ and T ₂ are calculated in advance and stored in the second storage unit 103. However, the size, weight, center of gravity position, etc. of the crane necessary for obtaining the hoisting rope tension are described. May be stored in advance, and T ₀ and T ₂ may be calculated based on these values and the boom undulation angle θ. In the above-described embodiments, to determine the boom weight correction sensitivity by performing comparison with the hoist cable tension when the boom weight W _b heavier than the weight of a predetermined, lighter W _b than the weight of the boom weight is predetermined The boom weight correction sensitivity may be obtained by comparison with the undulating rope tension in the case. First Embodiment and Second Embodiment
The configuration of the load calculation device of the third embodiment may be the same as that of the third embodiment. That is, the first storage unit and the second storage unit may be directly connected to the calculation unit.

In the first embodiment, the angle detector 15 is used as the angle detecting means, the load detector 14 is used as the load detecting means, and the processing in step S14 in FIG. The processing from step S9 of FIG. 5 to step S12 of FIG.
The processing of step 2 is performed by the load detection error calculating means, and the processing in step S
13 to the first angle shift calculating unit, the process of step S4 of FIG. 5 to the second angle shift calculating unit, the process of step S8 of FIG.
Corresponds to the weight shift predicting means, and step S12 in FIG. 6 corresponds to the tension shift calculating means. In the second embodiment, steps S113 to S12 in FIG.
The processing of step S120 in FIG. 11 corresponds to the load detection error calculating means, and the processing of step S120 in FIG.
The processing in step S121 of FIG.
The process of step S114 of the first step is performed by the first change amount calculating means.
The processing in step S118 in FIG. 11 corresponds to the second change amount calculating means, the processing in step S104 in FIG. 10 corresponds to the first angle shift calculating means, the processing in step S108 in FIG. The processing in step S112 is performed by the third angle deviation calculating means, the processing in step S115 in FIG.
9 to the boom own-weight deviation estimating means, the processing of step S116 in FIG. 11 to the jib third angle tension deviation calculating means,
The processing in step S116 in FIG. 11 corresponds to the jib fifth angle shift calculating unit.

[0070]

As described above in detail, according to the present invention, the deviation between the measured value of the hoisting rope tension due to the boom weight and the theoretical value in design and the error amount independent of the boom hoisting angle are used. Since the correction amount for calculating the actual load is calculated, the actual load of the crane can be calculated accurately and quickly. According to the invention described in claim 2,
Since the amount of change in the hoisting rope tension when the boom weight is heavier or lighter by a predetermined weight is calculated, the shift in the hoisting rope tension due to the shift in the boom weight can be accurately detected. According to the third to fifth aspects of the present invention, the actual load of the suspended load can be calculated only by changing the boom hoisting angle in two ways, so that the actual load can be quickly obtained. According to the invention of claim 6, based on the deviation between the measured value of the hoist rope tension due to the jib weight and the boom weight and the theoretical value in design, and the error amount independent of the jib hoist angle and the boom hoist angle. Since the correction amount for calculating the actual load is calculated, the actual load of the tower crane can be calculated accurately and quickly. According to the invention described in claim 7,
Since the amount of change in the hoisting rope tension when the boom weight and the jib weight are heavier or lighter by a predetermined weight is calculated, the shift in the hoisting rope tension due to the shift in the jib weight and the boom weight can be accurately detected. Claims 8 to 10
According to the invention described in (1), since the actual load of the suspended load can be calculated only by changing the jib hoist angle and the boom hoist angle in three ways, the actual load can be quickly obtained.

[Brief description of the drawings]

FIG. 1 is a claim correspondence diagram corresponding to claims 1 to 5;

FIG. 2 is a claim correspondence diagram corresponding to claims 6 to 10;

FIG. 3 is a block diagram of a first embodiment of a load calculating device for a crane according to the present invention.

FIG. 4 is an external view of a crane to which the load calculation device is attached.

FIG. 5 is a flowchart illustrating the operation of the calculation unit according to the first embodiment.

FIG. 6 is a flowchart following FIG. 5;

FIG. 7 is a diagram showing a relationship between a boom hoisting angle and a boom weight correction sensitivity.

FIG. 8 is an external view of a tower crane to which the load calculation device is attached.

FIG. 9 is a block diagram of a second embodiment of the load calculating device according to the present invention.

FIG. 10 is a flowchart illustrating the operation of the calculation unit according to the second embodiment.

FIG. 11 is a flowchart following FIG. 10;

FIG. 12 is a diagram showing the relationship between the tower jib hoisting angle and the tower jib weight correction sensitivity.

FIG. 13 is a diagram showing the relationship between the tower boom undulation angle and the tower boom weight correction sensitivity.

FIG. 14 is a block diagram of a third embodiment of the load calculating device according to the present invention.

FIG. 15 is a flowchart illustrating the operation of the calculation unit according to the third embodiment.

FIG. 16 is a block diagram of a fourth embodiment of the load calculating device according to the present invention.

FIG. 17 is a flowchart illustrating the operation of the calculation unit according to the fourth embodiment.

[Explanation of symbols]

 Reference Signs List 14 load detector 15 angle detector 101 calculation / comparison unit 101a calculation unit 101b comparison unit 102 first storage unit 103 second storage unit 104 switching unit 105 display 106 alarm device

Continuation of the front page (72) Inventor Kenichi Sagitani 650, Kunitachi-cho, Tsuchiura-shi, Ibaraki Pref. Hitachi Construction Machinery Engineering Co., Ltd. (56) References JP-A-2-81894 (JP, A) JP-A-62-299992 ( JP, A) JP-A-58-202285 (JP, A) JP-A-52-49555 (JP, A) JP-B-2-4516 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , (DB name) B66C 23/90

Claims (10)

(57) [Claims] 1. An angle detecting means for detecting an up-and-down angle of a boom, a load detecting means for detecting an up-and-down rope tension acting on an up-and-down rope for raising and lowering the boom, and based on the detected boom up-down angle and the up-and-down rope tension. A load calculating device for a crane provided with an actual hanging load calculating means for calculating an actual load of a suspended load, the actual measured value of the up-and-down rope tension caused by the difference between the actual boom weight and the designed boom weight, and Hoisting rope tension deviation calculating means for calculating the amount of deviation from the theoretical value of, and the error of the load detecting means itself, which is an error amount independent of the boom hoisting angle, included in the hoisting rope tension detected by the load detecting means. A load detection error calculating means for calculating; a deviation amount of the hoisting rope tension calculated by the hoisting rope tension deviation calculating means; and the load detecting error calculating means. Therefore, based on the calculated error amount, the correction amount calculating means for calculating a correction amount of the undulation rope tension detected by the load detecting means, the actual hanging load calculating means, based on the correction amount A load calculating device for a crane, which calculates an actual load of a suspended load. 2. The crane load calculating device according to claim 1, wherein the amount of change in the hoisting rope tension when the actual boom weight is heavier or lighter than a predetermined weight by a predetermined weight is determined according to the boom hoisting angle. A change amount calculating means for calculating the difference between the actual boom weight and the designed boom weight based on the change amount of the hoisting rope tension calculated by the change amount calculating means. A load calculating device for a crane, which calculates a deviation amount between an actually measured value of the hoisting rope tension and a designed theoretical value due to the boom hoisting angle. 3. The crane load calculating device according to claim 2, wherein when the boom hoisting angle is the first angle, an actual measured value of the hoisting rope tension detected by the load detecting means and a design theory. First angle shift calculating means for calculating the amount of shift from the value, and a difference between a measured value of the hoist rope tension detected by the load detecting means and a theoretical value in design when the boom hoist angle is the second angle. A second angle shift calculating means for calculating a shift amount, wherein the up-and-down rope tension shift calculating means comprises a shift amount of each up-and-down rope tension calculated by the first angle shift calculating means and the second angle shift calculating means. And the amount of change calculated by the change amount calculating means at the time of the first angle or the second angle, the undulation caused by the difference between the actual boom weight and the designed boom weight. Low A load calculating device for a crane, which calculates an amount of deviation between an actually measured value of the pull tension and a theoretical value in design according to a boom undulation angle. 4. The crane load calculating device according to claim 3, wherein the hoist rope tension deviation calculating means is each of the hoist ropes calculated by the first angle deviation calculating means and the second angle deviation calculating means. The amount of tension deviation,
On the basis of each change amount calculated by the change amount calculating means at the time of the first angle or the second angle,
Own weight deviation prediction means for predicting a weight difference between an actual boom weight and a designed boom weight; and an undulation caused by a difference between the actual boom weight and the designed boom weight based on the predicted weight difference. A load calculating device for a crane, comprising: a tension shift calculating unit configured to calculate a shift amount between a measured value of a rope tension and a theoretical value in design according to a boom angle. 5. The load calculating device for a crane according to claim 4, wherein said own weight shift predicting means calculates a shift amount of the undulating rope tension calculated by said first angle shift calculating means and said second angle shift calculation. The difference between the amount of deviation of the hoisting rope tension calculated by the means, the amount of change in the hoisting rope tension at the first angle calculated by the change amount calculating means, and the amount of the hoisting rope tension at the second angle. A load calculation device for a crane, wherein a weight difference between an actual boom weight and a designed boom weight is predicted based on a ratio of a difference between the change amount and a design amount. 6. A boom angle detection means for detecting an elevation angle of a boom, a jib angle detection means for detecting an elevation angle of a jib connected to a boom tip, and an elevation rope tension acting on an elevation rope for elevating the boom. A crane load calculating device comprising: a load detecting means for calculating the actual load of the suspended load based on the detected boom hoisting angle, jib hoisting angle and hoisting rope tension. Hoisting rope tension shift calculating means for calculating the amount of shift between the actual measured value of the hoisting rope tension and the designed theoretical value due to the difference between the jib weight and boom weight of the jib and the designed jib weight and boom weight; A load detection error, which is an error amount independent of the jib hoist angle and the boom hoist angle, included in the hoist rope tension detected by the detecting means is calculated. Weight detection error calculating means, and the load detection error is detected by the load detection means based on the deviation amount of the undulating rope tension calculated by the lifting rope tension deviation calculation means and the error amount calculated by the load detection error calculation means. And a correction amount calculating means for calculating a correction amount of the hoisting rope tension, wherein the actual hanging load calculating means calculates an actual load of the suspended load based on the correction amount. . 7. The crane load calculating device according to claim 6, wherein the amount of change in the hoisting rope tension when the actual jib weight is heavier or lighter than a predetermined weight by a predetermined weight is determined according to the jib hoisting angle. First change amount calculating means for calculating, and second change amount calculating means for calculating a change amount of the hoisting rope tension when the actual boom weight is heavier or lighter than a predetermined weight by a predetermined weight according to the boom hoisting angle. The hoist rope tension deviation calculating means is based on the change amount of the hoist rope tension calculated by the first change amount calculating means and the change amount of the hoist rope tension calculated by the second change amount calculating means. The deviation between the actual measured value of the undulation rope tension and the theoretical design value due to the weight difference between the actual jib weight and boom weight and the designed jib weight and boom weight, A load calculating device for a crane, which calculates according to a boom hoisting angle and a jib hoisting angle. 8. A crane load calculating device according to claim 7, wherein said hoisting rope detected by said load detecting means when the boom hoisting angle is a first angle and the jib hoisting angle is a second angle. First angle shift calculating means for calculating the amount of shift between the measured value of the tension and the theoretical value on design; and the load detecting means when the boom hoist angle is the first angle and the jib hoist angle is the third angle. Second angle shift calculating means for calculating the amount of shift between the measured value of the hoisting rope tension detected by the above and the theoretical value in design; and when the boom hoisting angle is the fourth angle and the jib hoisting angle is the fifth angle A third angle shift calculating means for calculating an amount of deviation between an actually measured value of the undulating rope tension detected by the load detecting means and a theoretical value in design; 1 Angle shift calculating means, said (2) When the amount of deviation of each hoist rope tension calculated by the angle shift calculating means and the third angle shift calculating means and the jib hoisting angle are the second angle, the third angle or the fifth angle, When each of the change amounts calculated by the first change amount calculation means and the boom undulation angle is the first angle or the fourth angle, the second change amount is calculated.
Based on each of the change amounts calculated by the change amount calculating means, the deviation between the measured value of the hoisting rope tension and the theoretical value in design caused by the difference between the actual boom weight and the designed boom weight is calculated by the boom. A load calculation device for a crane, wherein the load is calculated in accordance with a hoisting angle and a jib hoisting angle. 9. The crane load calculating device according to claim 8, wherein the hoisting rope tension shift calculating means is each hoisting rope calculated by the first angle shift calculating means and the second angle shift calculating means. The amount of tension deviation,
The actual jib weight and the designed jib weight are calculated based on the difference between the amounts of change calculated by the first change amount calculating means when the jib undulation angle is the second angle or the third angle. A jib own weight deviation estimating means for estimating a weight difference between the two, and a deviation amount of each hoist rope tension calculated by the second angle deviation calculating means and the third angle deviation calculating means;
When the boom undulation angle is the first angle or the fourth angle, the difference between the amounts of change calculated by the second change amount calculating means and the weight difference predicted by the jib self-weight shift predicting means are calculated. Boom weight shift prediction means for predicting a weight difference between an actual boom weight and a designed boom weight based on the actual boom weight and a design boom weight based on the weight difference predicted by the boom weight shift prediction means. A deviation amount between the measured value of the hoisting rope tension due to the difference with the boom weight and a theoretical value in design, and a tension deviation calculating means for calculating the deviation amount according to the boom hoisting angle and the jib hoisting angle. Crane load calculation device. 10. The crane load calculating device according to claim 9, wherein the actual jib weight and the design in the case where the boom hoist angle is the first angle and the jib hoist angle is the third angle are set. Jib third angle tension deviation calculating means for calculating the amount of deviation between the measured value of the hoisting rope tension due to the difference from the jib weight and the theoretical value on design; and the jib hoisting angle when the boom hoisting angle is the fourth angle. Is the fifth angle, the fifth angle tension of the jib for calculating the amount of deviation between the actually measured value of the up-and-down rope tension due to the difference between the actual jib weight and the designed jib weight and the designed theoretical value. A deviation calculating means, wherein the jib self-weight deviation estimating means comprises: a deviation amount of the hoisting rope tension calculated by the first angle deviation calculating means and a deviation amount of the hoisting rope tension calculated by the second angle deviation calculating means. And the difference between The actual jib weight and the designed jib weight are determined based on the ratio of the difference between the amounts of change calculated by the first change amount calculating means when the tilt angle is the third angle or the fifth angle. The boom own weight deviation estimating means calculates a deviation amount calculated by the jib second angle tension deviation estimating means from the deviation amount of the undulating rope tension calculated by the second angle deviation calculating means. Subtracting the difference between the result of subtraction and the result of subtracting the amount of deviation calculated by the jib fifth angle tension deviation calculating means from the amount of deviation of the lifting rope tension calculated by the third angle deviation calculating means; When the angle is the first angle or the fourth angle, the actual boom weight and the designed boom weight are calculated based on the ratio of the difference between the respective amounts of change calculated by the second change amount calculator. A load calculating device for a crane, wherein the weight difference is predicted.