JP6565247B2 - Swivel crane - Google Patents

Description

  The invention of this application relates to a swivel crane having a swivel stop control function capable of automatically and gently stopping a swivel operation of a boom without causing a swing of a suspended load. In addition to swivel operation, when the winch is raised and lowered, the boom swivel operation is automatically and gently performed without causing the swinging of the suspended load as in the case of the boom swivel operation alone. The present invention relates to a configuration of a swivel crane having a swivel stop control function that can be stopped.

Some pivotable with the pivoting crane boom, in order to safely automatically stopping the turning operation of the boom so as to correspond to the working range of the restricted region (turning limit), the actual boom by a boom pivot angle degree detecting means approaching boom turning operation while detecting the turning angle of the nearby pivot predetermined limit, there is one drop the turning speed gradually, with a gradually boom slewing stop control function automatically stopping.

  On the other hand, in the swing crane, the swing of the load corresponding to the hanging length of the suspended load is generated during the swing operation of the boom, so that it cannot be safely stopped as it is.

  Therefore, in the case of a swing crane equipped with a boom turning operation stop control function as described above, when the boom turning operation is stopped, the swing time is the same as the load swing period according to the hanging length of the suspended load at that time. A boom turning stop control method that lowers the turning speed of the boom is adopted (as an example of a swing crane having a load swing suppressing function for suppressing load swing when a suspended load is positioned at a target position, for example, a patent (Ref. 1).

  According to such a boom turning automatic stop control method, the turning operation of the boom can be automatically and gently stopped without causing the swing of the suspended load.

JP 2008-74579 A

  However, in the case of a swing crane, when performing the swing operation of the boom as described above, there are many cases where the winch is simultaneously wound up or lowered while performing the swing operation of the boom as well as the swing operation of the boom ( For example, refer to the winch operation signal output in addition to the boom operation signal shown in (a) of the time chart of FIG.

  Even in the case where the winch hoisting or lowering operation is accompanied in addition to the boom turning operation, the boom turning operation according to the load swing period t1 (seconds) is stopped, as described above. It can be considered that the operation of the winch is also automatically and gently stopped (see, for example, the turning output signal (b) and the winch output signal (c) in the time chart of FIG. 4).

  However, if the winch hoisting or lowering speed is lowered while lowering the swing speed of the boom in this way, the winch is hoisted or lowered during the pivot of the boom, which should suppress the swing of the load. The hanging length of a suspended load changes from moment to moment.

  As a result, the load swing period t1 (seconds) is not fixed, and the boom swing speed can be reduced in the same time as the load swing period t1 (seconds) as in the case of the boom swing operation only. In addition, there is a problem that the turning operation cannot be automatically stopped gently while preventing the suspended load from swinging.

  The invention of this application was made to solve such a problem. The winch stop time required from when the winch stop control is started until the winch stops is calculated, and the boom turning limit position is calculated. Correspondingly, an early winch according to the stop time of the winch so that the winch is stopped at the time when the turning stop control is started at which the turning speed is lowered at the load swing period corresponding to the hanging length of the suspended load. By performing the stop control of the boom, even when the winch is wound up or lowered together with the boom turning operation, the boom turning operation can be gently stopped without causing the swinging of the suspended load. An object of the present invention is to provide a swivel crane that can be used.

In order to solve the above-described problems, the invention of this application includes the following problem solving means.
(1) First Problem Solving Means In other words, the first problem solving means of the present invention includes a load swing period calculating means for calculating a load swing period of a suspended load from a suspended length of the suspended load, and turning of the boom. Boom turning angle detecting means for detecting an angle, and when the boom turning angle detected by the boom turning angle detecting means approaches the turning limit position, the boom turning angle is calculated according to the load swing period calculated by the load swing period calculating means. A winch stop control means for stopping a winch and a winch stop control means for stopping the winch in a swing crane having a boom turning stop control means for automatically stopping the boom turning while reducing the boom turning speed. Winch stop time calculating means for calculating the winch stop time required until the winch stops after starting the operation, and when the winch stop control starts. Based on the boom turning speed, a turning angle of the boom at the time the time obtained by adding a to the calculated load pendulum period by computed winch downtime and the load swinging period calculating means has passed by the winch stop time calculating means A boom turning angle calculating means for calculating, and a boom turning limit determining means for determining whether or not the boom turning angle calculated by the boom turning angle calculating means is in the vicinity of the boom turning limit position; by limiting determination unit, when the swivel-position location of the boom moved by boom swivel angle calculated by the boom pivoting angle calculation means is determined to be near the turning limit position of the boom, the winch stop control After the winch is stopped by the means, the load swing circumference calculated by the load swing period calculating means by the boom turning stop control means The turning of the boom is stopped while lowering the turning speed according to the period.

  That is, in the configuration of the first problem solving means of the present invention, first, a winch stop time calculating means is provided in addition to the winch stop control means, and the winch stop control means starts the winch stop control. The winch stop time required until the winch actually stops is calculated.

Next, in addition to that, the winch stop time calculated by the winch stop time calculating means and the load swing period calculating means are calculated based on the boom turning speed at the start of the winch stop control by the winch stop control means. a boom pivoting angle calculation means for calculating a turning angle of the boom at the time the time obtained by adding the load pendulum period has elapsed, the swivel position location of a boom that is moved by a boom swivel angle calculated by the boom pivoting angle calculation means Boom turning limit determination means is provided for determining whether or not the boom turning limit position is in the vicinity of a predetermined boom.

And, thereby, on the basis of the boom pivoting speed during the winch stop control start to predict the swivel position location of the boom at the time the time combined the winch stop time and load pendulum period has elapsed, which is the predicted swivel position location of boom, whether around pivot limit position of the boom which is set in advance.

The swivel position location of said the determined boom, from the time when was around turning limit position of the boom, which performs a winch stop control by Uinchichi stop control means first, the winch stop time has elapsed, the The boom turning stop control means is actuated to start the stop control of the boom turning operation in accordance with the load swing period, and the boom turning operation is gently stopped.

On the other hand, swivel-position location of the the determined boom when not in the vicinity of the turning limit position of the boom, is continued as it is turning operation.

  According to such a configuration, at least the actual boom turning angle detected by the boom turning angle detection means approaches the turning limit position in the work range restricted area or the like, and the turning must be stopped while the turning speed is reduced. At the critical stage, the winch operation is automatically stopped.

  Therefore, during the combined operation in which the winch operation was performed while the boom was being turned, the boom load was not generated as in the case of the single operation in which the winch operation was not performed. The turning can be automatically stopped gently.

  As a result of the above, according to the invention of this application, even when the winch hoisting or lowering operation is performed together with the boom turning operation, the suspended load is shaken as in the case of only the boom turning operation. Without this, it is possible to gently and automatically stop the turning operation of the boom.

It is the schematic which shows the basic composition of the crane main-body part of the turning crane which concerns on embodiment of invention of this application. It is a block diagram which shows the structure of the control circuit part of the turning stop control apparatus of the turning crane which concerns on the same embodiment. FIG. 3 is a time chart showing winch stop control and boom swing stop control action based on the winch stop control by the control circuit of FIG. 2 of the swing crane swing stop control device according to the embodiment; It is a time chart which shows the problem by the boom turning stop control apparatus of the conventional turning type crane in the case where winding operation of a winch is accompanied.

  Hereinafter, the configuration and operation of a predetermined form for carrying out the invention of this application will be described in detail with reference to FIGS.

<Basic configuration of a swing crane to which the invention of this application is applied>
First, FIG. 1 shows a basic configuration of a crane main body portion of a swing crane to which the boom swing stop control device in the swing crane of the invention of this application is applied. In this embodiment, for example, a mobile swing crane (truck crane) is employed as an example of the swing crane.

  That is, the swivel crane of this embodiment has a vehicle (carrier) 1 configured to be able to travel with wheels 1a, 1a,... And a driver's seat 1b, and swivels above the vehicle body 1c of the vehicle 1. A swivel body 3 provided so as to be turnable via a support body 2, and a base end side of the swivel body 3 via a hinge (foot pin) 4 are pivotally attached to a boom support portion of the swivel body 3. The working boom 6 is provided so as to be able to undulate and extend and retract in the longitudinal direction via an extendable cylinder (not shown), and the boom from the winch 30 on the proximal end side revolving structure 3 of the boom 6. 6 includes a wire rope 7 that extends to the tip end side boom head portion (sheave portion) and extends downward from the boom head portion, and a hook block 8 that is suspended from the wire rope 7.

  At the time of the lifting work, a lifting load 31 having a predetermined load is suspended from the hook block 8 and a winch motor (see reference numeral 24 in FIG. 2) for rotating the winch drum (not shown) of the winch 30 is used. It is wound up and down by driving. At the same time, the necessary lifting work is performed by raising, lowering, extending, and turning the boom 6.

  The boom 6 can be raised, retracted, and swiveled by the work range restriction parameter of the work range restriction device provided on the crane. When approaching, the boom 6 is automatically stopped by the boom turning automatic stop control device that automatically stops the turning operation in accordance with the load swing period.

  Further, outriggers 9, 9,... Projecting in the left and right directions are provided on the front and rear of the vehicle body 1c of the vehicle 1. A crane driver's seat 3a is provided on the front end side of the revolving structure 3, and a counterweight 3b is provided on the rear end side.

  In the case of this embodiment, the boom 6 is composed of, for example, three booms (a three-stage boom) including a base boom 6a, an intermediate boom 6b, and a top boom 6c.

  Although not shown in the drawings, the turning support 2 is provided on a pedestal supported on the vehicle body 1c side, a large-diameter fixed gear (swivel wheel) fixed to the upper part of the pedestal, and an upper surface of the cradle. A ball bearing that supports the revolving unit 3 so as to be horizontally rotatable, a cylindrical center joint (rotary joint) that vertically penetrates the central shaft portion of the cradle, and a concentric state provided above the center joint. And a slip ring portion having a cylindrical structure.

  Further, a boom turning motor (see reference numeral 25 in FIG. 2) made of a hydraulic motor (or an electric motor) is provided on the revolving body 3 side, and the pinion of the boom turning motor is fixed to the large diameter. By meshing with a gear and being driven to rotate by the boom turning motor, the turning body 3 can be arbitrarily turned right or left on the ball bearing around the center joint as a rotation center. .

  As a result, the boom 6 moves in the right direction or the left direction at a predetermined turning angle within the work range restriction area defined by the work range restriction device (including when there is an obstacle such as a building at the work site). A swivel operation is performed in the range.

<Boom turning operation stop control and various detection means necessary for winch stop control>
As described above, the invention of this application starts the stop control of the winch 30 (outputs a stop command signal) based on the rotational speed of the winch drum of the winch 30 at that time, and then actually winches 30 (winch motor 24). And the winch stop time t2 required until the winch drum stops), and correspondingly, the turning operation of the boom 6 is stopped at the load swing period t1 corresponding to the hanging length l of the suspended load 31. Prior to the start of the boom turning stop control, the stop control of the winch 30 is started first, and the turning stop control of the boom 6 is started when the stop time of the winch 30 has elapsed, The winch 30 is stopped at the time when the boom turning stop control is started, and the winch 30 is not wound up or down. Even when the swing operation of the boom 6 is performed, the swing operation of the boom 6 can be gently and automatically stopped without causing the swing of the suspended load 31 as in the case where the swing operation is not performed. ing.

  In order to enable such control, the swing crane shown in FIG. 1 is provided with detection means as shown in the control circuit diagram of FIG.

  That is, the winch drum rotation amount detecting means 12 for detecting the rotation amount n of the winch drum of the winch 30 is provided in the winch 30 portion, and the boom 6 portion is used for detecting the actual turning angle φ of the boom 6. A turning angle detecting means 14 is provided.

  The winch drum rotation amount detection means 12 is constituted by, for example, a pulse encoder, and detects the rotation amount n of the winch drum based on the number of pulses output according to the rotation amount of the winch drum.

  The detection data detected by each of these detection means is input to a predetermined calculation means portion of a control circuit in a microcomputer-type turning stop control unit 10 constituting a crane turning stop control device as described below, and is necessary. Arithmetic processing and control processing are performed.

<Configuration of the control circuit portion of the crane turning stop control unit>
That is, the crane turning stop control unit 10 of this embodiment, as shown in detail in FIG. 2, for example, is based on the winch drum rotation amount n detected by the winch drum rotation amount detection means 12 and suspends the load 31. The suspension length calculation means 16 for calculating the suspension length 1 (the suspension length from the boom head by the wire rope 7) 1 and the suspension of the suspended load 31 calculated by the suspension length calculation means 16 Based on the length l, the load swing period calculating means 17 for calculating the load swing period t1 of the suspended load 31 and the winch drum rotation amount n detected by the winch drum rotation amount detecting means 12 are input, and the winch Based on the rotation speed of the winch drum obtained from the amount of rotation of the drum per unit time (number of pulses from the pulse encoder), A winch stop time calculating means 18 for calculating a winch stop time t2 from when the winch 30 stop control is started by the control means 22 until the winch 30 (winch motor 24) is actually stopped, and the boom turning angle detecting means 14 The boom turning speed calculating means 15 for calculating the turning speed ω of the boom 6 based on the actual boom turning angle φ detected by the above-described operation, the actual boom turning speed ω calculated by the boom turning speed calculating means 15, The winch stop time t2 calculated by the winch stop time calculation means 18 and the load swing period t1 corresponding to the hanging length of the suspended load 31 calculated by the load swing period calculation means 17 are input, respectively, and the current boom turning While turning at the speed ω, a time (t1 + t) obtained by combining the stop time t2 of the winch 30 and the load swing period t1 ), A boom turning angle calculating means 19 for calculating the turning angle φ1 of the boom 6 at the time of elapse of time, and a boom turning limit position setting means 21 for setting the turning limit position φ2 of the boom 6 corresponding to the work range restriction area in advance. , boom swivel position location of the boom 6 is moved by the boom pivoting angle φ1 calculated by the boom pivoting angle calculation means 19 (predicted swivel position location) is set by the boom turning limit position setting means 21 it is determined whether the near turning limit position φ2 of 6, the turning of the boom 6 to swivel position location of the boom 6 (prediction swivel position location) is set by the boom turning limit position setting means 21 If it is near the limit position φ2, is the winch stop command signal S1 outputted to the winch stop control means 22 to stop the winch motor 24 and the winch stop command signal S1? When the winch stop time t2 elapses, the boom turning stop command signal S2 is sent to the boom turning stop control means 23 for stopping the turning of the boom 6 in accordance with the load swing period t1 calculated by the load swing period calculating means 17. Boom turning limit determining means 20 for outputting, winch stop control means 22 for stopping the winch motor 24 in response to the winch stop command signal S1 supplied from the boom turning limit determining means 20, and the boom turning limit determination When the boom turning stop command signal S2 is input from the means 20 (when the winch stop time t2 calculated by the winch stop time calculating means 18 has elapsed), the load swing calculated by the load swing period calculating means 17 is calculated. The boom turning motor 25 is controlled in accordance with the cycle t1, and the turning speed ω of the boom 6 is reduced. And a boom slewing stop control means 23 for stopping the turning of the boom 6 while.

  The calculation of the suspension length by the suspension length calculating means 16 for calculating the suspension length l of the suspended load 31 is as described above with the length (expansion / contraction amount) L of the boom 6 at that time. Although it is obtained from the change in the rotation amount n of the winch drum, more specifically, it is calculated in consideration of the diameter of the winch drum, the multiplication factor of the wire rope, and the like.

  Further, the boom turning speed calculation means 15 for calculating the turning speed of the boom 6 uses a detection value of the actual boom turning angle φ output from the boom turning angle detection means 14 configured using, for example, a potentiometer. The current boom turning speed ω is calculated from the change in the boom turning angle φ for each sampling cycle.

  The load swing period calculating means 17 calculates the load swing period t1 based on the suspension length l of the suspended load 31 calculated by the suspended load length calculating means 16 (t1 = 2π√l / g). However, g shows a gravitational acceleration).

  Further, in the above description, the hanging length l of the suspended load 31, load swing period t1, winch stop time t2, boom turning angle φ, boom turning angle φ1, boom turning limit position φ2, boom turning speed ω, etc. The unit is as follows (the same applies to the following description).

Hanging length of suspended load 31: l, load swing period t1: s (second), winch stop time t2: s (second), boom turning angle φ: rad, boom turning angle φ1: rad, boom turning limit position φ2: rad, boom turning speed ω: rad / s
<Boom turning operation stop control and winch stop control based on it>
Next, in this embodiment, using the control circuit having the configuration shown in FIG. 2, the following stop control of the boom turning operation and winch stop control which is the premise of the boom turning operation stop control are performed.

  The winch stop control and the boom turning operation stop control are executed as a continuous control sequence linked to each other as shown in, for example, (b) to (a) of the time chart of FIG. ing.

  That is, in the configuration of the control circuit of FIG. 2, first, in addition to the winch stop control means 22 for controlling the driving state of the winch 30, the winch stop time calculating means 18 is provided, and the winch drum of the winch 30 at that time is provided. Based on the rotational speed, the winch stop time t2 required from when the winch stop control means 22 starts the stop control of the winch 30 until the winch 30 (winch motor 24) actually stops is calculated.

Next, in addition to this, the winch stop time t2 calculated by the winch stop time calculation means 18 and the load swing period calculation means based on the boom turning speed ω at the start of the winch stop control by the winch stop control means 22 The boom turning angle calculating means 19 for calculating (predicting) the turning angle φ1 of the boom 6 at the time when the time (t1 + t2) added with the load swing period t1 calculated by 17 is passed, and the boom turning angle calculating means 19 calculation (prediction) has been swivel position location of the boom 6 when moved by the boom pivoting angle φ1, for example pivoting of the boom 6 is predetermined by the boom turning limit position setting means 21 in correspondence with the working range limited region Boom turning limit determining means 20 for determining whether or not the position is near the limit position φ2 is provided.

Then, based on the boom turning speed ω at the start of the winch stop control, the turning angle φ1 of the boom 6 at the time when the time (t1 + t2) that combines the winch stop time t2 and the load swing period t1 has elapsed is calculated. (prediction), and swivel-position location of the boom 6 when moved by the boom pivoting angle φ1 which is the calculation (prediction) is in the vicinity of the turning limit position φ2 boom 6 in the working range limited region that is the preset It is determined whether or not there is.

The swivel position location of the boom 6 is the determination, when was around turning limit position φ2 the boom 6, first stops the driving of the winch motor 24 by the winch stop control means 22, the operation of the winch 30 Stop. When the drive stop command for the winch motor 24 is issued, all the operations other than the turning operation such as the expansion / contraction of the boom 6 and the undulation are stopped at the same time so that the working radius and the hanging length of the suspended load 31 are not changed. (See FIG. 3B).

  After that, when the winch stop time t2 elapses, the boom turning stop control means 23 is operated from the time when the winch stop time t2 elapses (see FIG. 3B), and the load swing period t1 is reached. The stop control of the combined boom turning operation is started, and the turning of the boom 6 is gently stopped (see FIG. 3A).

  On the other hand, when the determined turning angle position of the boom 6 is not near the turning limit position φ2 of the boom 6, the turning operation is continued as it is.

  According to such a configuration, at least the actual turning angle φ of the boom 6 detected by the boom turning angle detection means 14 approaches the turning limit position φ2 in the work range restriction region, and the turning speed ω is reduced while the turning speed ω is reduced. When it is necessary to stop the operation of the winch 30, the operation of the winch 30 is automatically stopped, and subsequently, the boom turning stop control is started.

  Accordingly, during the combined operation in which the winch 30 is being wound up or lowered while the boom 6 is being turned, the lifting load 31 is not lifted or lowered as in the case where the winch 30 is not being lifted or lowered. The turning operation of the boom 6 can be gently and automatically stopped without causing a load swing.

  In this case, during the period from when the stop control of the winch 30 is started to when the winch 30 is actually stopped, the boom 6 can be turned at least at a normal turning speed. Further, even after the winch 30 stops, turning is possible, but the turning speed is gradually reduced (see FIG. 3A).

  As a result, according to the above-described embodiment, when the winch 30 is wound up or lowered together with the swing operation of the boom 6, the load of the suspended load 31 is the same as when only the swing operation of the boom 6 is performed. It is possible to gently and automatically stop the turning operation of the boom 6 without causing a swing.

  1 is a vehicle, 2 is a turning support, 3 is a turning body, 5 is a hoisting cylinder, 6 is a boom, 7 is a wire rope, 8 is a hook block, 10 is a swing automatic stop control unit of a crane, and 12 is a winch drum rotation amount. Detecting means, 14 is a boom turning angle detecting means, 16 is a hanging length detecting means, 17 is a load swing period calculating means, 18 is a winch stop time calculating means, 19 is a boom turning angle calculating means, and 20 is a boom turning limit determination. Means, 21 is a boom turning limit position setting means, 22 is a winch stop control means, 23 is a boom turning stop control means, 24 is a winch motor, and 25 is a boom turning motor.

Claims (1)

Load swing period calculating means for calculating the load swing period of the suspended load from the hanging length of the suspended load, boom turning angle detecting means for detecting the turning angle of the boom, and the boom detected by the boom turning angle detecting means Boom turning stop control means for automatically stopping the turning of the boom while decreasing the turning speed of the boom in accordance with the load swing period calculated by the load swing period calculating means A winch stop control means for stopping the winch, and a winch stop time for calculating a winch stop time required for the winch to stop after the winch stop control means starts the winch stop control. Calculated by the winch stop time calculation means based on the calculation means and the boom turning speed at the start of the winch stop control. A boom pivoting angle calculation means for calculating a turning angle of the boom at the time the time obtained by adding a to the calculated load pendulum period has elapsed by winch stop time and the load swinging period calculating means has, at the boom pivot angle calculating means Boom turning limit determining means for determining whether or not the calculated boom turning angle is in the vicinity of the boom turning limit position is provided, and the boom calculated by the boom turning angle calculating means by the boom turning limit determining means is provided. when the swivel position location of the moved above the boom only turning angle is determined to be near the turning limit position of the boom, after stopping the winch with the winch stop control means, the boom slewing stop control means To stop the boom turning while reducing the turning speed in accordance with the load swing period calculated by the load swing period calculating means. Rotary Cranes, characterized in that the.

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