JPH075256B2 - Load steady rest control method for hoisting and carrying device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to the end of movement of a carrying device when carrying a load by a hoisting carrying device such as a crane, especially when carrying a short distance in a horizontal straight line direction. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load steadying control method for controlling a load that is sometimes conveyed so that no swing remains.

[Conventional technology]

Generally, when the load is carried by the hoisting and carrying device, it is important to control so that the load carried at the end of the movement of the carrying device is not shaken from the viewpoint of work safety and efficiency.

Next, the conventional method of such load steadying control is described in the third section.
The crane device shown in the figure will be described. First, the crane device 10 is installed, for example, on a traveling rail 16 installed on a corner post 14 (only two of which are shown) in a warehouse 12, and on the traveling rail 16 so as to be longitudinally travelable. It comprises a traveling girder 20 provided with a traverse rail 18 and a traverse trolley 22 erected on the traverse rail 18 so as to traverse.
The load 24 is configured so as to be hoistable and hoistable via a wire 26.

Then, in the conventional load steadying control method, the position Pa
When the upper load 24 is transported to the position Pd at a distance Da, the crane device 10 is operated to show the traverse trolley 22 first in the position section Pa to Pd in relation to FIG. As the load 24 runout cycle (However, L is the suspension length of the load 24) Accelerating operation time t _u for equal acceleration operation to reach the maximum set speed v _e , and then for the position section Pb to Pc at the maximum set speed v _e A constant speed operation is performed for a constant speed operation time t _e , and finally, a deceleration operation is performed at a constant speed for a deceleration operation time t _{d having} a swing cycle α of the load in the position sections Pc to Pd to stop the load 24 on the position Pd.

In this case, the swing cycle α of the load 24 is accurately calculated by a microcomputer or the like by measuring the suspension length L of the load 24, and the acceleration / deceleration times t _u and t _d are accurately matched to the cycle α time. That is, since the trolley 22 is moved accurately with equal acceleration and deceleration within the cycle α time of the load 24,
No run-out remains on the load 24 at the end of acceleration / deceleration operation of the trolley 22. Further, since the required trolley constant velocity operation time t _e is accurately calculated and set in correspondence with the maximum set speed v _e of the trolley 22 which is preset to a predetermined value, the load 24 accurately determines its position. Stopped on position Pd. In addition, load 24
If the height at the start of movement or the height at the end of movement is different from the height at the time of movement, the load 24 is hoisted or unwound before the start of movement or after the end of movement.

Here, the equation of motion of the system consisting of the trolley 22, the load 24 and the wire 26 is derived from the Lagrange equation of motion. If the horizontal displacement of the trolley 22 is x, the deflection angle (suspension angle) of the load 24 is θ, the length of the wire 26 is L, the mass of the load 24 is m, and the gravitational acceleration is g, then Lagrangian The equation of motion F is expressed by F = (1/2) m [(L cos θ + sin θ−) ² + (L sin θ−cos θ) ² ] + mgL cos θ (1). From equation (1), Here, assuming that the deflection angle θ is small, cos θ≈1, sin θ≈
θ, and assuming that the length of the wire 26 does not change,
Putting it as = 0, + (g / L) θ = / L (3) is obtained from the equation (2). Further, assuming that = β (constant acceleration), θ _{t = 0} = θ ₀ , and _{t = 0} = ₀ , from the equation (3), θ = (θ ₀ −β / g) cosωt + ( ₀ / ω) sinωt + β / g ... (4A) =-? (? _0- ? / G) sin? T + ₀ cos? T ... (4B) is obtained. However, ω = 2π / α = (g / L) ^1/2 .

Looking at these equations (4A) and (4B), when ωt = (2π / α) t = 2nπ (n = 1,2 ...), θ = θ ₀ regardless of the acceleration β (deceleration −β). And = ₀ are obtained and θ ₀ = 0, ₀ = 0, that is, if there is no shake at the beginning of the acceleration / deceleration operation, if the acceleration / deceleration operation time is set to an integral multiple of the cycle, no shake remains.

In Fig. 2, if the load 24 does not swing in the initial stage of uniform acceleration operation, it means that there is no runout at the end of uniform acceleration operation after t _u = 2π (Lb / g) ^1/2. Since the load 24 does not swing at the beginning of the subsequent constant deceleration operation, one cycle of the deflection of the load 24, even after the end of the uniform deceleration operation after t _d = 2π (Lb / g) ^1/2 Is not remaining.

[Problems to be solved by the invention]

As described above, according to the above-described load steadying control method, it is possible to carry the load without causing the runout to remain in the load. However, such a control method inherently has a drawback that it requires a long transportation time even when the load transportation distance is short, as described below.

That is, in FIG. 3, when the load 24 is carried in the position sections Pa to Pf which are separated by a relatively short distance Db, the load 24 is equal to the uniform acceleration operation and the uniform deceleration operation as shown in FIG. The transportation is completed by. However, in this case, the uniform acceleration operation time t _u and the uniform deceleration operation time t _d are both
24 runout cycles Since it is set to the time, no matter how the transport distance Db is shortened, it is the minimum to transport the load 24. Need time. In this case, the maximum set speed v _m is set to a low value regardless of the recommended target maximum speed v _e .

Therefore, it is an object of the present invention to provide a load steadying control method for a hoisting and carrying device that can carry a load in a short carrying distance in a short time without leaving the runout in the load at the end of movement of the load.

[Means for solving problems]

In order to achieve the above object, the load steadying control method of the hoisting and conveying device according to the present invention, in the short-distance conveyance of the load by the hoisting and conveying device in the horizontal straight line direction, the hoisting and conveying device has a load oscillation period of 1 / Accelerated operation from the stopped state to a predetermined maximum set speed sequentially and continuously at time intervals of 4,
It is characterized in that constant deceleration operation is performed from the maximum set speed to the stopped state, uniform acceleration operation is performed from the stopped state to the maximum set speed, and uniform deceleration operation is performed from the maximum set speed to the stopped state.

[Action]

The hoisting and transporting device is operated and moved by four equal acceleration / deceleration operations, each of which is 1/4 of the load swing cycle. Therefore,
The load is completely transported within the load swing cycle. That is, the transportation is completed in half the time required by the conventional control method.

On the other hand, in this case, the swing cycle of the load is accurately calculated by a microcomputer and the acceleration / deceleration time is accurately matched with 1/4 of this swing cycle time, so that the swinging action acting on the load is reliably stopped. To be done. Therefore, the swing does not remain in the load at the end of the movement of the load.

〔Example〕

An embodiment of a load steadying control method for a hoisting and carrying device according to the present invention will be described in detail below with reference to the accompanying drawings. For convenience of explanation, the same components as those of the conventional structure shown in FIGS. 3 and 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

First, the crane device will be described. In FIG. 1, the crane device 10 is, for example, a traveling rail 16 installed on a corner post 14 (only two of which are shown) in a warehouse 12, and a longitudinal traveling on the traveling rail 16 is possible. It consists of a traveling girder 20 provided with a traverse rail 18 erected on the traverse trolley 22, and a traverse trolley 22 erected so as to traverse on the traverse rail 18, and a load 24 can be hoisted and unwound on the traverse trolley 22 via a wire 26. It is configured to be suspended.

Next, regarding the case where the load 24 on the position Pa is transported to the position Pf at a short distance Db by this crane device 10,
The load steadying control method of the present invention will be described with reference to FIG. 1 and FIG. 2 drawn in correlation with FIG. In the control method of the present invention, the traverse trolley 22 is loaded
24 runout cycles (However, L is the suspension length of load 24) 1/4 time interval, At a time interval of, first, in the position sections Pa to Pg, a uniform acceleration operation is performed from a stopped state, then in position sections Pg to Pe, a uniform deceleration operation is performed to a stopped state, and further, the position sections Pe to Ph
At the same time, the acceleration operation is started from the stopped state, and finally the position section
In Ph to Pf, the deceleration operation is performed at a constant speed until it stops. As a result, the load 24 moves to the position Pf without remaining runout.
The transportation is completed. If the height of the load 24 at the start of movement or the height at the end of movement is different from the height at the time of movement, the load 24 before the movement starts or after the movement ends
Is wound up or down.

Here, the deflection angle θ and the deflection speed of the load 24 are (4A) and (4A) for each of the _uniform acceleration operation period t _u1 , the _uniform deceleration operation period t _d1 , the _uniform acceleration operation period t _u2, and the _uniform deceleration operation period t _d2 , respectively. 4B) Calculate from the formula.

Regarding the _uniform acceleration operation period t _u1, there is no fluctuation in the initial stage, that is, θ ₀ = 0, ₀ = 0, θ _u1 = − (β / g) cos ωt + β / g, _u1 = ω (β / g) sin ωt, for etc. deceleration operation period t _d1, the acceleration as _{-β, θ d1 = (β /} g) cosωt-β / g + (u1 / ω) sinωt, d1 = -ω (θ u1 + β / g) sinωt + u1 cosωt, for the uniform acceleration operation period t _u2 , θ _u2 = − (β / g) cosωt + β / g, + ( _d1 / ω) sinωt, _u2 = −ω (θ _d1 −β / g) sinωt + _d1 cosωt, etc. Regarding the deceleration operation period t _d2 , assuming that the acceleration is −β, θ _d2 = (β / g) cosωt−β / g + ( _u2 / ω) sinωt, _d2 = −ω (θ _u2 + β / g) sinωt + _u2 cosωt , And ωt = 2π / 4 = π / 2, the above equations are sequentially calculated, and the operation with constant acceleration β is performed for α / 4 period, and the operation with constant deceleration −β is α / 4. During the period of, driving with constant acceleration β is α / 4
As the runout θ _a of the load 24 and the runout speed _a after the operation of the constant deceleration-β is sequentially performed for the period of α / 4 at the end,
From the expressions of θ _d2 and _{d 2} , θ _a = 0 and _a = 0 are obtained, and the swing of the load 24 is stopped.

The maximum setting speed v _m ′ of the trolley 22 is Ie Is calculated in advance by the microcomputer from the relational expression of, and the uniform acceleration a _u and the uniform deceleration a _d of the trolley 22 are respectively Similarly, it is preliminarily calculated and set by the microcomputer from the relational expression. The maximum set speed v _m ′ in the control method of the present invention
Corresponds to twice the maximum set speed v _m in the conventional control method.

As described above, according to the control method of the present invention, the transportation of the load is completed within the swing cycle of the load. Therefore, the second
As shown by the chain double-dashed line in the figure, the carrying time is reduced to half as compared with the conventional control method that requires twice the carrying time of the load swing cycle. On the other hand, the swing cycle of the load,
The maximum set speed, acceleration / deceleration, and acceleration / deceleration operation time of the transportation device are accurately measured or calculated and set, so that the swinging action that acts on the load is reliably suppressed. Therefore, the swing does not remain in the load at the end of the movement of the load.

Although the present invention has been described with reference to the preferred embodiments, it goes without saying that the present invention can be modified in many ways without departing from the spirit thereof.

〔The invention's effect〕

As described above, the load steadying control method for the hoisting and transporting device according to the present invention is a short-distance transport in the horizontal linear direction of the load by the hoisting and transporting device, and the hoisting and transporting device is 1/4 times the runout cycle of the load. Acceleration operation from a stopped state to a predetermined maximum set speed is performed continuously and continuously at intervals, a uniform deceleration operation is performed from the maximum set speed to the stopped state, a uniform acceleration operation is performed from the stopped state to the maximum set speed, and the maximum set Since it is configured to perform decelerating operation from speed to stop,
The load can be completed within the swing cycle of this load. Therefore, it is possible to reduce the transportation time in the conventional control method that requires a transportation time that is twice the load swing cycle to half.

On the other hand, according to the control method of the present invention, the swing cycle of the load, the maximum set speed of the transportation device, the acceleration, the deceleration and the acceleration,
Since the deceleration operation time is accurately measured or calculated and set, the swinging action acting on the load is reliably stopped. Therefore, the swing does not remain in the load at the end of the movement of the load.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a crane device for carrying out a load steadying control method for a hoisting and carrying device according to the present invention, and FIG. 2 is a crane device for carrying out the control method according to the present invention shown in FIG. Fig. 3 is a perspective view of a crane device for carrying out a load steadying control method for a conventional hoisting and carrying device, and Fig. 4 is a crane for carrying out the conventional control method shown in Fig. 3. It is a moving speed diagram with respect to the transportation time of an apparatus. 10 …… Crane device, 12 …… Warehouse 14 …… Pillar, 16 …… Traveling rail 18 …… Traverse rail, 20… Traverse girder 22 …… Traverse trolley, 24 …… Load 26 …… Suspended wire Pa, Pg, Pe, Ph, Pf …… Load position or traverse trolley position Db …… Short transportation distance L …… Suspension length of load a _u …… Acceleration of traverse trolley a _d …… Deceleration of traverse trolley v _m ´ …… maximum set speed t _u ...... rampant trolley etc. acceleration operation time t _d ...... rampant trolley etc. deceleration operation time of rampant trolley

Claims (1)

[Claims] 1. In a short-distance transport of a load by a hoisting and carrying device in a horizontal straight line direction, the hoisting and carrying device is sequentially and continuously at a time interval of 1/4 of a load swing cycle from a stopped state to a predetermined maximum set speed. Hoisting transport characterized by performing uniform acceleration operation, uniform deceleration operation from the maximum set speed to the stopped state, uniform acceleration operation from the stopped state to the maximum set speed, and uniform deceleration operation from the maximum set speed to the stopped state Load steady rest control method for equipment.