JP3321988B2 - Cable crane rest resting method and apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for restraining a load of a cable crane which conveys a suspended load along a main rope while lifting and lowering the load. The present invention relates to a method and an apparatus for preventing a cable crane from swaying a load.

[0002]

2. Description of the Related Art As shown in FIG. 13, a cable crane is suspended between a machine tower 4 and a sub tower 5 by a hoisting rope 1 for lifting and lowering a suspended load 2, and the trolley 3 is transmitted. It has a main rope 6 and a traversing rope 7 attached to the main rope 6 for running the trolley 3. One end of the traversing rope 7 is fixed to the trolley 3, reaches the sub-tower 5 along the main rope 6 from the fixing point, is hung on a roller 131 provided on the sub-tower 5, and is returned above the main rope 6. It reaches the machine tower 4, is wound around the traversing drum 132 of the machine tower 4, extends from the machine tower 4 along the main rope 6 to the trolley 3, and the other end is fixed to the trolley 3. When the traversing drum is rotated, the traversing rope 7 is wound on the one hand and paid out on the other. Thus, the length of the traversing rope 7 from the trolley 3 to the sub tower 5 and the mechanical tower 4 from the trolley 3
The trolley 3 can be moved between the machine tower 4 and the sub tower 5 by increasing or decreasing the length of the traversing rope 7 up to the length. Further, the hoisting rope 1 has one end fixed to the sub-tower 5, reaches the trolley 3 along the main rope 6 from the fixing point, is hung by the rollers 133 in the trolley 3, and is hung downward.
It is hung up by the roller 134 of the suspended load 2 and rises upward, is hung by another roller 135 in the trolley 3, and from this roller 135 to the machine tower 4 along the main rope 6, the winding drum of the machine tower 4 136. By rotating the hoist drum, the amount of hanging of the hoist rope 1 can be increased or decreased to raise or lower the suspended load 2. The traveling of the trolley 3 does not affect the hanging amount of the hoisting rope 1.

In practice, the driving of the hoisting rope 1 and the driving of the traversing rope 7 are performed in parallel, so that the suspended load 2 can be transported along a desired route along the main rope 6 while raising and lowering.

[0004] In a cable crane, when a trolley is accelerated, a suspended load swings due to the action of a pendulum. Since this pendulum motion continues even after the suspended load arrives, it is difficult to remove the suspended load or take out the contents, which may be dangerous.

[0005] A method utilizing the cycle of a pendulum is known as a method of preventing the load from swaying. In this method, the suspended portion is assumed to be a single pendulum, and a half period T of the pendulum is determined from the suspended length L of the hoisting rope, that is, the length of the pendulum.

[0006]

(Equation 1)

Once the trolley traverse is accelerated and then accelerated again after a lapse of time T, the swing of the suspended load caused by the first acceleration is canceled by the second-stage acceleration, and the swing stops. This method is called a two-stage acceleration method, and the time T is called a two-stage acceleration timing. The two-stage acceleration timing is uniquely determined by the suspension length L.

Since the acceleration is required when the trolley starts traversing and when the trolley stops (deceleration), the pattern representing the speed change due to the two-stage acceleration timing along the time is a double trapezoid. Present.

[0009]

In the cable crane, hangers are attached to the main ropes 6 at intervals to support the traversing ropes 7 along with the main ropes 6. Has been passed over. The traversing rope 7 is suspended from the main rope 6 at a plurality of locations. For this reason, sag (slack) exists in the traversing rope 7. Because of the presence of sag, the speed of the trolley does not always follow the acceleration of the traversing rope at a certain timing. Even if the acceleration timing determined to be able to perform steady rest with a crane having no sag (such as a jib crane) is applied to a cable crane, a sufficient steady rest effect cannot be obtained.

FIG. 10 shows the change in the driving speed of the traversing rope, the change in the speed of the trolley traverse, the change in the speed of hoisting, and the swing of the suspended load caused by the change in the time when the conventional two-stage acceleration method is used. It is shown. 0 seconds to 2
The traversing rope drive and the trolley perform a double trapezoidal movement in 2 seconds, and the winding is performed in 10 to 40 seconds.
At both the acceleration and the deceleration, the shake generated by the first-stage acceleration is offset by the second-stage acceleration, and there is no shake after the arrival of the suspended load. As described above, there are cases where the effect of the steady rest is well exhibited by the conventional method.

FIG. 11 shows an example of failure. 0 seconds to 4
In three seconds, the traversing rope drive performs a double trapezoidal motion,
Winding is performed between seconds and 45 seconds. During deceleration,
The speed change of the trolley traverse does not coincide with the drive speed change of the traverse rope. Then, it can be seen that even after 45 seconds of the arrival of the suspended load, the deflection remains. This is because the speed change of the trolley traverse does not match the drive speed change of the traverse rope. That is, the anti-sway effect is lost due to the effect of sag.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a method and an apparatus for preventing a cable crane from having a steadying pattern corresponding to slack of a traversing rope.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention calculates the trolley traveling start and the route of the suspended load from the target position and the height difference of the suspended load, and starts the trolley traveling along this route or the purpose. Find the sag delay rate from the position and the hanging length of the hoisting rope, and
Generate a steady rest pattern having accelerated timing ,
The operation is performed according to the steady rest pattern.

The apparatus comprises a route calculating means for calculating a trolley traveling start and destination position and a route of the suspended load from the height difference of the suspended load, a trolley traveling start or target position on this route, a hanging length of a hoisting rope, From sag to late
The system includes a steady rest pattern generating means for obtaining a postponement rate and generating a steady rest pattern having an acceleration timing corresponding to the delay rate, and an operating means for operating according to the steady rest pattern.

[0015] When the trolley traveling start or destination position is farther than a predetermined distance from the machine tower, the steady rest pattern may be determined by a fuzzy rule that inputs the trolley traveling start or destination position and the hanging length of the hoisting rope. Good.

[0016]

The delay in following the speed of the trolley with respect to the acceleration driving of the traverse rope is due to sag. The delay is small when the amount of sag between the machine tower that drives the traversing rope and the trolley is small, and when the amount of sag is large, the delay is large. Since the amount of the sag is substantially proportional to the distance from the machine tower to the trolley, the magnitude of the delay can be estimated according to the trolley position. If the magnitude of the delay is known, the acceleration timing at which the swing of the suspended load is canceled can be determined in consideration of the magnitude of the delay.

According to the present invention, steadying is performed at an acceleration timing according to the suspension length and the trolley position, and the acceleration timing is given and executed as a pattern of a hoisting drive and a traverse drive. Thus, when the traverse rope is accelerated and driven, the trolley is accelerated later by the sag, and the acceleration of the trolley cancels out the swing of the suspended load.

In the steady rest device, the route calculation means calculates the route of the suspended load from the trolley traveling start and destination positions and the height difference of the suspended load. The pattern generating means generates a steadying pattern having a manner of accelerating the hoisting and traversing such that the swing of the suspended load is stopped based on the trolley position in this path and the hanging length of the hoisting rope. The operating means operates according to the steady rest pattern. With this, when the suspended load arrives at the target height at the target position,
The swing of the suspended load is stopped, and it is possible to immediately remove the suspended load and put the contents in and out.

Examining the relationship between the distance from the machine tower to the trolley and the effect on the delay of the trolley acceleration, as shown in FIG. 12, when the trolley is closer to the machine tower than the middle between the machine tower and the auxiliary tower. There was almost no effect, and there was a slight effect around the middle, and the effect rapidly changed and increased with distance from the middle to the side of the sub-tower, and it was found that there was a large effect near the sub-tower. Therefore, the steady rest pattern taking into account the influence of sag becomes particularly important when the trolley is accelerated on the side of the sub tower from the middle. Therefore, when the trolley traveling start position is farther than a predetermined distance from the machine tower, or
When the destination position is farther than a predetermined distance from the machine tower, the steady rest pattern is determined by a fuzzy rule that inputs the start of travel or the destination position and the suspension length. The relationship between the suspension length and trolley position and the period and delay of the pendulum is complicated, and it is difficult to obtain a linear relational expression. However, since the fuzzy rule is used, it is necessary to generate an optimal steady rest pattern. Can be.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

As shown in FIG. 1, a cable crane provided with a steady rest device comprises a trolley 3 for lifting and lowering a suspended load 2 by a hoisting rope 1, a mechanical tower 4 and a subtower 5
And the main rope 6 that is passed between and transmits the trolley 3.
And a traversing rope 7 suspended from the main rope 6 at a plurality of locations to allow the trolley 3 to travel. The structure of fixing and bridging each rope is as described in the conventional example. As shown, a sag 8 is formed on the traversing rope 7. The hoisting motor for driving the hoisting rope 1 and the traversing motor for driving the traversing rope 7 are installed in the machine tower 4, and can perform the hoisting and traversing parallel operation as described in the conventional example. A load rest device that operates the hoist motor and the traverse motor according to the steady pattern is incorporated in an operation panel (not shown) installed in the machine tower 4 or the like. In this cable crane, for example, the ready-mixed concrete is transported by a bucket from a ready-mixed concrete supply unit located in the machine tower 4 and driven into the bucket. Used in loading.

The distance from the machine tower 4 to the sub-tower 5 is S, the distance from the machine tower 4 to the trolley 3 (the trolley position) is X, the height difference of the suspended load 2 is H, and the suspended length of the hoisting rope 1 is L. In this embodiment, the cable crane reciprocates from the machine tower 4 to an arbitrary position to transport the contents of the bucket. Trolley position X =
0). The height difference between the height of the main rope 6 and the driving location in the machine tower 4 is H.

As shown in FIG. 2, the load steadying device comprises a route calculating means 21 for calculating a route of the suspended load 2 from the trolley traveling start and destination positions and a height difference of the suspended load 2, and a trolley on this route. A steady pattern generating means 23 for generating a steady pattern 22 having a manner of accelerating the hoisting and traversing so as to stop the swing of the suspended load 2 based on the position and the hanging length of the hoisting rope 1, and according to the steady pattern. Operating means (not shown) for operating
Position calculation means 24 for calculating the position from the number of rotations of the hoisting motor and the number of rotations of the traversing motor, and the operation panel for determining the arrival position of the suspended load 2 by the operation of the operator.

The anti-sway device of the cable crane operates according to the flowchart of FIG.

Next, the operation of the embodiment will be described.

According to the flowchart of FIG. 3, the operating means represents the arrival position designated by the operator as coordinates (step 1), and the position calculating means 24 represents the current position of the suspended load 2 as coordinates (step 2). The route calculating means 21 determines from the coordinates whether this operation is going or returning, obtains the trolley traveling start and destination positions and the height difference H of the suspended load, and calculates the driving amount of the traversing rope 7. Then, the driving amount of the hoisting rope 1 is calculated (step 3), and the route of the suspended load by the combined traversing and hoisting operation is calculated so that the operation can be performed in the shortest time while taking into account obstacles on the way (step 3). Step 4).

The pattern generating means 23 generates a steady rest pattern on the machine tower side (step 5). Go,
That is, even if the machine tower 4 is at the traveling start position of the trolley or returns, that is, whether the machine tower 4 is at the target position of the trolley, the machine tower side steady rest pattern is determined by the conventional suspension length L. The two-stage acceleration timing described above can be used.

Next, the pattern generating means 23 includes the mechanical tower 4
To generate a steady rest pattern on the other side of
The trolley traveling start position X in the case of returning or the trolley destination position X in the case of going is obtained, and the suspension length L is obtained (step 6). Then, switching is performed so as to generate a different steady rest pattern depending on whether or not the trolley position X is larger than S ′ (step 7). Where S ′ is S / 2
The value is larger than S and smaller than S in this embodiment.
9S.

If the trolley position X is smaller than S ', the trolley position X and the suspension length L are input to the fuzzy rule to determine k (step 8). k is a coefficient for obtaining the acceleration timing Td from the half cycle T of the pendulum calculated by the equation (1). Using this k, an acceleration timing Td at which Td = kT is calculated, and a steady rest pattern of two-stage acceleration is generated (step 9).

If the trolley position X is larger than S ', step A is executed. In step A, first, the acceleration is changed. That is, as shown in FIG. 4B, the acceleration at the first stage acceleration timing is changed, and the speed change 41 becomes gentle. The acceleration timing Td = kT is calculated in the same manner as described above, and generates a two-step acceleration steady rest pattern having different accelerations.

Note that the steady rest pattern when the trolley position X is larger than S 'is represented by the step A shown in FIG.
In addition to the above processing, the number of acceleration stages may be increased or the acceleration timing calculation formula may be changed. That is, FIG.
In step (c) B, k is obtained, the acceleration timing Td that satisfies Td = kT is calculated, and the three-step acceleration steady rest pattern shown in FIG. 4D is generated. Further, in step C of FIG. 4E, k is obtained, the acceleration timing Td at which Td = 3 kT (1.5 cycle) is calculated, and the steady rest pattern of the two-stage acceleration of FIG. 4F is generated. .

When the steady rest pattern on the opposite side of the machine tower 4 is generated in this way, it is combined with the steady rest pattern on the machine tower 4 (step 10).
The steady rest pattern required for the operation of the stroke is used. The operating means creates an operation sequence of the hoist motor and the traversing motor based on the steady rest pattern of one stroke (step 11), and the operation of the cable crane is executed by this operation sequence (step 12).

Next, the fuzzy rules will be described.

FIG. 5 is a graph of a membership function constituting the antecedent part of the fuzzy rule. FIG. 5A shows a relationship between a trolley position X, which is one input of a fuzzy rule, which is a trolley traveling start or destination position, and a membership function. Here, in the cable crane, the distance S from the machine tower 4 to the sub tower 5 is 269.0 m. The membership function is calculated as follows.
Up to m, up to 246 m, up to 269 m. FIG. 5B shows the relationship between the hanging length L of the hoisting rope 1 which is the other input of the fuzzy rule and the membership function. Here, in the cable crane, the maximum length of the hoisting rope 1 is 147.5 m.
It is assumed that Membership function is 17.5m
Up to 30.5m, up to 56.5m,
Up to 90.0 m is up to 147.5 m.

FIG. 6 is a graph of a membership function constituting the consequent part of the fuzzy rule. FIG. 6A shows the relationship between the outgoing delay rate and the membership function. FIG. 6B shows the relationship between the return delay rate and the membership function.

Table 1 is a table for obtaining a membership function of the going and returning delay rates from the membership function of the trolley position X and the membership function of the suspension length L.

[0037]

[Table 1]

In the fuzzy rule, by inputting the start or destination position X and the suspension length L,
The going and returning delay rates are derived via FIG. 5, Table 1 and FIG. The steady rest pattern defines the acceleration timing according to the derived delay rate.

FIG. 7 shows a change in the driving speed of the traversing rope, a change in the speed of the trolley traverse, a change in the speed of the hoisting, and a change in the speeds of steps 8 and 9 of the present invention along substantially the same path as that in FIG. The resulting swing of the suspended load is shown over time. 0 seconds to 4
In three seconds, the traversing rope drive performs a double trapezoidal motion,
Winding is performed between seconds and 46 seconds. During deceleration,
The speed change of the trolley traverse does not coincide with the drive speed change of the traverse rope. However, after 46 seconds of the arrival of the suspended load, no run-out remains, and a better anti-sway effect is obtained compared to the case of FIG.

FIG. 8 shows an example in which a three-step acceleration of step B is performed when returning from a position close to the sub tower. Since the operation is performed from a position close to the side tower, the trolley traverses drastically in response to the driving of the traversing rope, and the swing is severe, but the swing is suppressed after the arrival of the suspended load.

FIG. 9 shows an example in which a two-step acceleration of 1.5 cycles of step C is performed when returning from a position close to the sub tower. Since the operation is performed from a position close to the side tower, the swing is severe and large, and the swing is suppressed after the arrival of the suspended load.

[0042]

The present invention exhibits the following excellent effects.

(1) Since the steady rest pattern is generated in consideration of the influence of the sag that varies depending on the trolley position, even if the cable crane has the sag, an acceleration timing for canceling the shake can be obtained.

(2) Since the swing is eliminated when the suspended load arrives, the removal of the suspended load and the loading / unloading of the contents can be started immediately, and the work efficiency and the safety are improved.

[Brief description of the drawings]

FIG. 1 is a side view of a cable crane showing one embodiment of the present invention.

FIG. 2 is a block diagram of the cable steady rest device of the cable crane according to the present invention.

FIG. 3 is a flowchart of a cable steady rest device for a cable crane according to the present invention.

FIGS. 4 (b), (d), and (f) are acceleration timing charts showing the steady rest pattern of the present invention.
(A), (c), and (e) are flowcharts for generating respective acceleration timings.

FIG. 5 is a graph of a membership function constituting the antecedent part of the fuzzy rule of the cable steady rest device of the present invention.

FIG. 6 is a graph of a membership function constituting a consequent part of a fuzzy rule of the cable steady rest device of the present invention.

FIG. 7 shows a change in driving speed of a traversing rope in the present invention;
It is the graph which showed the change of the speed of the trolley traverse, the change of the speed of hoisting, and the swing of the suspended load which arises with this over time.

FIG. 8 shows a change in driving speed of a traversing rope according to the present invention;
6 is a graph showing a change in the speed of the trolley traverse and the swing of a suspended load caused by the change over time.

FIG. 9 shows a change in driving speed of a traversing rope in the present invention;
6 is a graph showing a change in the speed of the trolley traverse and the swing of a suspended load caused by the change over time.

FIG. 10 shows a conventional driving speed change of a traversing rope,
It is the graph which showed the change of the speed of the trolley traverse, the change of the speed of hoisting, and the swing of the suspended load which arises with this over time.

FIG. 11 shows a conventional driving speed change of a traversing rope,
It is the graph which showed the change of the speed of the trolley traverse, the change of the speed of hoisting, and the swing of the suspended load which arises with this over time.

FIG. 12 is a graph showing the relationship between the distance from the machine tower and the effect of sag.

FIG. 13 is a side view showing a fixing and bridging structure of each rope in the cable cranes of the related art and the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hoisting rope 2 Suspended load 3 Trolley 4 Machine tower 5 Sub tower 6 Main rope 7 Traversing rope 21 Path calculation means 22 Sway-prevention pattern 23 Sway-prevention pattern generation means

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yasuma Miyoshi 1-19-10 Mohri, Koto-ku, Tokyo Ishikawa-Shima-Harima Heavy Industries, Ltd. Koto Office (72) Inventor Takakazu Shimizu 3-1-1 Toyosu, Koto-ku, Tokyo No. 15 Ishikawajima-Harima Heavy Industries Co., Ltd.In the Toji Technical Center (72) Inventor Fumiaki Honda 3-1-1, Toyosu, Koto-ku, Tokyo Ishikawajima-Harima Heavy Industries Co., Ltd.In the Toji Technical Center (56) JP-A-6-115878 (JP, A) JP-A-4-106096 (JP, A) JP-A-4-59598 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B66C13 / 22 B66C 21/00

Claims (3)

(57) [Claims] 1. A trolley for raising and lowering a suspended load by a hoisting rope is transmitted to a main rope suspended between a machine tower and a sub tower, and the trolley is run by a traversing rope suspended at a plurality of points on the main rope. In the method for stopping the swing of the suspended load, the path of the suspended load is calculated from the trolley traveling start and the target position and the height difference of the suspended load, and the trolley traveling start or the target position and the hanging length of the hoisting rope on this route are calculated. Find the delay rate due to sag from the
A steady rest method for a cable crane, characterized in that a steady rest pattern having an acceleration timing according to a deferment rate is generated, and an operation is performed according to the steady rest pattern. 2. A trolley for lifting and lowering a suspended load by a hoisting rope, a main rope suspended between a machine tower and a subtower to transmit the trolley, and a traversing rope suspended from the main rope at a plurality of locations to run the trolley. And a route calculation means for calculating a trolley traveling start and destination position and a height difference of the suspended load, and a trolley traveling start or destination position on this route. The delay rate due to sag is calculated from the suspension length of the hoisting rope and the
A load steadying device for a cable crane, comprising: a steadying pattern generating means for generating a steadying pattern having a speed timing; and an operating means for operating in accordance with the steadying pattern. 3. When the trolley traveling start or the destination position is farther than a predetermined distance from the machine tower, the steady rest pattern is determined by a fuzzy rule that inputs the trolley traveling start or the destination position and the hanging length of the hoisting rope. 2. A cable crane according to claim 1, further comprising:
How .