JPS6260358B2

JPS6260358B2 -

Info

Publication number: JPS6260358B2
Application number: JP54127009A
Authority: JP
Inventors: Minoru Arai
Original assignee: Kawaden Co Ltd
Current assignee: Kawaden Co Ltd
Priority date: 1979-10-02
Filing date: 1979-10-02
Publication date: 1987-12-16
Also published as: JPS5652384A

Description

[Detailed description of the invention]

本発明はクレーンの斜行防止装置に関する。クレーンが走行レール上を走行する場合、特に
トロリに荷重を吊つた状態でトロリが一方の走行
レール側に寄つた場合、又は横風の影響によつて
走行車輪の輪圧は片側が大となり反対側は小さく
なる。この状態で走行すれば、一般にトロリの寄
つた側が遅れ勝になる。このためクレーンは斜行
し、走行レールの側面に車輪フランジが当り、ク
レーンはその桁、脚に捩りを受けて走行する。従来の斜行防止装置のないクレーンにおいて
は、走行中に生ずる斜行のため、走行レールの側
面に車輪フランジが当るため車輪フランジの摩耗
が著しく多い。更に、クレーン構造のガーダ及び
脚を捩りに対して強固な構造とする必要があり、
これはクレーンの重量増となる。既知の斜行防止装置の例として、ガータと脚上
面に旋回可能の装置を設けて旋回角度を検出して
クレーンの斜行を防止する装置は、ガーダと脚と
の接続部分の構造が複雑になり、クレーン重量が
増加する。他の斜行防止装置として、スパン間の
レーザ光線によつて斜行を検出する装置があるが
クレーン本体、吊荷、人体等がレーザ光線を遮断
しない位置に設ける必要があり、取付場所の制約
を受け、調整保守が困難である。別の斜行防止装置として、走行レール両側に全
長に亘つてピンラツクを設置し、クレーンの両脚
に取付けたピニオンの回転差を検出して斜行を検
知する装置があるが、走行レールに沿うピンラツ
ク上の塵埃、土砂を清掃するのが著しく困難であ
る。本発明はクレーンの斜行を生ずる原理を探求し
た結果、斜行が生じた時は走行車輪の輪圧に差が
生じ、輪圧の小さい側が先行し又は一方がスリツ
プした場合にガーダ又は脚に捩りモーメントが発
生すること、及び各種の偏荷重及び横風の影響下
で各車輪の輪圧の変化に一定の条件があり、輪圧
変化を比較することによつて斜行の発生及び走行
ブレーキ等を作用させるべき位置を判定し得るこ
とを知つた結果得られたものである。本発明によるクレーンの斜行防止装置は、レー
ル上を走行する走行車輪と、走行モータと、走行
ブレーキと、桁上を横行するトロリとを有するク
レーンの斜行防止装置において、複数の上記走行
車輪の輪圧を検出する検出手段と、上記検出手段
によつて検出した輪圧相互間の大小を比較する比
較手段と、上記比較手段の出力の応じて上記走行
モータ、走行ブレーキの少なくとも一方を制御す
る制御装置とを具備する。本発明による斜行防止装置は、所要数の圧縮型
荷重計と、簡単な比較回路で構成でき、既知の斜
行防止装置に比較して著しく簡単な装置となり、
クレーン重量に対する影響はほとんどない。しか
も斜行の初期判定が容易であるため、既知のクレ
ーンを軽量化することも可能となる。本発明を例示とした実施例並びに図面について
説明する。第１〜３図に示すクレーン１には桁２、揺脚
３、剛脚４が設けられている。揺脚３と剛脚４と
の下端に支持したトラツク機構５は夫々複数の車
輪６，７，８，９を支承する。各車輪はレール１
０，１１上を走行する。第４，５図はトラツク機構５の詳細を示し、揺
脚３の下端に回動可能に取付けたトラツク１２の
両端に台車１３をピン１４によつて回動可能に支
承する。台車１３は軸受１５、車軸１６を介して
２個の車輪６を支承する。車輪６は両側フランジ
型とし、レール１０上を走行する。所要の車輪に
駆動歯車１７を取付け、図示しない駆動装置によ
つて駆動する。所要の車輪に図示しないブレーキ
装置を組合せて所要位置に停止する。図示の例で
は１組のトラツク機構５の１個のトラツク１２に
は２個の台車１３を取付け、台車１３は２個の車
輪６を支承する例を示したが、トラツクに対する
台車の数、車輪の数はクレーンの大きさ及び容量
によつて定める。本発明によつて、各トラツク１２の最外側の車
輪の軸受１５と車軸１６との間に圧縮型荷重計２
０を介挿する。圧縮型荷重計をトラツク１２と台
車１３の枢支ピン１４の部分に取付けることもで
きる。トロリ２１が吊荷２２を吊つた状態でクレーン
１が走行レール１０，１１上を走行する場合に、
トロリ２１が一方の走行レール側に寄つた時は走
行車輪の輪圧はトロリの寄つた側が大きく、反対
側が小さい。この状態で走行動作を行なうと一般
にトロリの寄つた側が遅れる傾向に生ずる。この
ため、クレーンは斜行し、走行レールの側面に車
輪の一方のフランジが当り、桁２、脚３，４に捩
りを受けながら走行する。本発明によつて、車輪
の輪圧を検出し、このデータに基づいて斜行を制
御する。この方法について以下に説明する。第１〜３図に示す通り、走行総重量、即ちクレ
ーン重量と吊荷重量との加算重量によつて、揺脚
３の車輪６，７にはP₁、剛脚４の車輪８，９には
P₂の車輪圧が発生する。クレーン脚には風、走行の際の慣性力等による
水平荷重が発生し、水平荷重に基づく輪圧は上述
の走行総重量に基づく輪圧に対して正又は負の荷
重として作用する。水平荷重はクレーンの走行方
向に平行の荷重Ｗ_Hに基づく輪圧±Ｐ_Hと、走行方
向に直角の荷重Ｗ_Pに基づく輪圧±Ｐ_Wとが作用す
る。実際に作用する荷重は斜方向であつて直角分
力と平行分力とを有する場合があるが、簡単のた
め、以下の式においては何れか一方の力が作用す
るものとして取扱う。輪圧Ｐ_WとＰ_Hとの合成値が
作用しても斜行の検出ができることは以下の式に
よつて明らかである。クレーンの走行に際して吊荷２２が桁２の一端
に偏つている場合には揺脚３、剛脚４の各駆動輪
に速度差が生じ易く、このため斜行を生じ易くな
る。斜行を生じた時には、各車輪は斜行により発
生する水平方向の斜行力Ｖのモーメントによる垂
直力を受け、輪圧が変化する。このように、斜行
を生じた時は機体は捩りモーメントを受け、各車
輪に作用する垂直力は一方の脚の両端で互に反対
方向になる。他方は脚との間では、対角線位置に
ある車輪が同方向の垂直力となる。一般に走行遅れを生じた側の脚の進行方向前方
の車輪は下方の垂直力を受け、進行方向後方の車
輪は上方の垂直力を受ける。他の脚の車輪は逆方
向の垂直力を受ける。従つて、一方の脚の両端の荷重計取付車輪の輪
圧を比較すれば、両車輪間には斜行の生じた時に
輪圧の差が生ずる。少なくとも揺脚又は剛脚の何
れかの荷重計の指示の差によつて斜行が検出され
る。車輪６，７を揺脚３において荷重計を取付けた
車輪とし、車輪８，９を剛脚４において荷重計を
取付けた車輪とし、P₆は車輪６が受ける合成垂直
力、即ち輪圧とし、P₇，P₈，P₉をそれぞれ車輪
７，８，９が受ける輪圧とする。説明上、車輪７，９を東側、車輪６，８を西
側、剛脚４を南側、揺脚３を北側と仮定する。桁に平行の水平荷重Ｗ_Pによつて、揺脚３、剛
脚４に作用する圧力はＷ_P・Ｈ／Ｌ＝±Ｐ_W 桁に直角の水平荷重Ｗ_Hによつて、揺脚３、剛
脚４に作用する圧力は、Ｗ_H・Ｈ／Ｂ＝±Ｐ_H 走行中に発生する斜行力Ｖによつて揺脚３、剛
脚４に作用する圧力は、Ｖ・Ｈ／Ｂ＝±Ｐ_V 各脚の一隅の車輪数をｎ個とし、水平荷重の方
向は第３図に示した場合に、斜行が生じた状態の
輪圧の変化は次式で示される。揺脚の車輪６，７の車輪圧は、ａ P₆＝Ｐ_１−Ｐ_Ｗ／２ｎ−Ｐ_Ｖ／ｎ＜P₇＝Ｐ_１−Ｐ_Ｗ／２ｎ＋Ｐ_Ｖ／ｎｂ P₆＝Ｐ_１−Ｐ_Ｈ／２ｎ−Ｐ_Ｖ／ｎ＜P₇＝Ｐ_１＋Ｐ_Ｈ／２ｎ＋Ｐ_Ｖ／ｎ水平荷重Ｗ_Hの方向が逆の時は、ｃ P₆＝Ｐ_１＋Ｐ_Ｈ／２ｎ−Ｐ_Ｖ／ｎ P₇＝Ｐ_１−Ｐ_Ｈ／２ｎ＋Ｐ_Ｖ／ｎ剛脚の車輪８，９の車輪圧は、ａ P₈＝Ｐ_２＋Ｐ_Ｗ／２ｎ＋Ｐ_Ｖ／ｎ＞P₉＝Ｐ_２＋Ｐ_Ｗ／２ｎ−Ｐ_Ｖ／ｎｂ P₈＝Ｐ_２−Ｐ_Ｈ／２ｎ＋Ｐ_Ｖ／ｎ P₉＝Ｐ_２＋Ｐ_Ｈ／２ｎ−Ｐ_Ｖ／ｎｃ P₈＝Ｐ_２＋Ｐ_Ｈ／２ｎ＋Ｐ_Ｖ／＞P₉＝Ｐ_２−Ｐ_Ｈ／
２ｎ−Ｐ_Ｖ／ｎ上述の式において、揺脚の場合のｃ式、剛脚の
場合のｂ式では大小の比較が不可能となる。従つ
て、ｃの状態では剛脚側、ｂの状態では揺脚側の
輪圧の差を検出し、先行した脚側の走行モータ又
は走行ブレーキを制御して斜行を停止させる。組合せ及び制御は下表の通りになる。 The present invention relates to a crane skew prevention device. When a crane travels on a running rail, especially when a load is suspended on the trolley and the trolley moves to one side of the running rail, or due to the influence of a crosswind, the wheel pressure of the running wheels increases on one side and increases on the other side. becomes smaller. If you run in this condition, the side where the trolley is closer will generally be the one that wins later. As a result, the crane travels diagonally, the wheel flanges hit the side of the traveling rail, and the crane travels while being twisted by the girders and legs. In conventional cranes without a skew prevention device, the wheel flanges come into contact with the sides of the traveling rail due to the skew that occurs during travel, resulting in significant wear on the wheel flanges. Furthermore, the girders and legs of the crane structure need to have a strong structure against torsion.
This increases the weight of the crane. As an example of a known skew prevention device, a device that prevents the crane from skewing by installing a swingable device on the girder and the upper surface of the leg to detect the swing angle has a complicated structure at the connection part between the girder and the leg. This increases the weight of the crane. Another skew prevention device is a device that detects skew using a laser beam between spans, but it must be installed in a position where the crane body, suspended load, human body, etc. will not block the laser beam, and there are restrictions on the installation location. adjustment and maintenance is difficult. Another skew prevention device is a device that detects skew by installing pin racks along the entire length on both sides of the traveling rail and detecting the difference in rotation between pinions attached to both legs of the crane. It is extremely difficult to clean the dust and dirt on top. The present invention was developed as a result of exploring the principles that cause cranes to skew. When skew occurs, there is a difference in the wheel pressure of the traveling wheels, and if the side with lower wheel pressure takes the lead or one slips, the girder or leg is affected. There are certain conditions in which a torsional moment occurs and the wheel pressure of each wheel changes under the influence of various unbalanced loads and crosswinds, and by comparing the changes in wheel pressure, it is possible to detect the occurrence of skew, travel brakes, etc. This was obtained as a result of knowing that it is possible to determine the position where the action should be applied. A crane skew prevention device according to the present invention is a crane skew prevention device having a traveling wheel running on a rail, a traveling motor, a traveling brake, and a trolley traveling on a girder. a detecting means for detecting the wheel pressure of the wheel, a comparing means for comparing the magnitude of the wheel pressures detected by the detecting means, and controlling at least one of the traveling motor and the traveling brake according to the output of the comparing means. and a control device. The skew prevention device according to the present invention can be configured with a required number of compression type load cells and a simple comparison circuit, and is significantly simpler than known skew prevention devices.
There is little effect on crane weight. Furthermore, since the initial determination of skew is easy, it is also possible to reduce the weight of known cranes. Embodiments and drawings illustrating the present invention will be described. The crane 1 shown in FIGS. 1 to 3 is provided with a girder 2, a rocking leg 3, and a rigid leg 4. A track mechanism 5 supported at the lower ends of the rocking leg 3 and the rigid leg 4 supports a plurality of wheels 6, 7, 8, 9, respectively. Each wheel is rail 1
Driving on 0.11. 4 and 5 show details of the track mechanism 5, in which a truck 12 is rotatably attached to the lower end of the rocking leg 3, and a truck 13 is rotatably supported at both ends by pins 14. The truck 13 supports two wheels 6 via bearings 15 and axles 16. The wheels 6 have flanges on both sides and run on rails 10. A drive gear 17 is attached to a required wheel and driven by a drive device (not shown). A brake device (not shown) is combined with the required wheels to stop the vehicle at the required position. In the illustrated example, two carts 13 are attached to one track 12 of one set of track mechanisms 5, and the cart 13 supports two wheels 6. The number of cranes depends on the size and capacity of the crane. According to the invention, a compression load cell 2 is provided between the bearing 15 of the outermost wheel of each truck 12 and the axle 16.
Insert 0. A compression type load cell can also be attached to the pivot pin 14 of the truck 12 and the bogie 13. When the crane 1 travels on the traveling rails 10 and 11 with the trolley 21 hanging the load 22,
When the trolley 21 approaches one of the running rails, the wheel pressure of the running wheels is greater on the side where the trolley is closer and smaller on the opposite side. If a traveling operation is performed in this state, the side where the trolley is closer generally tends to lag behind. As a result, the crane travels diagonally, one flange of the wheel touches the side of the traveling rail, and the crane travels while being torsioned by the girder 2 and legs 3 and 4. According to the present invention, wheel pressure is detected and skew is controlled based on this data. This method will be explained below. As shown in Figures 1 to 3, depending on the total traveling weight, that is, the added weight of the crane weight and the hanging load, P ₁ is applied to the wheels 6 and 7 of the rocking leg 3, and P 1 is applied to the wheels 8 and 9 of the rigid leg 4. teeth
A wheel pressure of P ₂ is generated. Horizontal loads are generated on the crane legs due to wind, inertia force during traveling, etc., and the wheel pressure based on the horizontal load acts as a positive or negative load on the wheel pressure based on the above-mentioned total traveling weight. The horizontal load is a wheel pressure ±P H based on a load W _H parallel to the traveling direction of the crane, and a wheel pressure ±P _W based on _a load W _P perpendicular to the traveling direction. Although the load that actually acts may be in an oblique direction and have a right angle component force and a parallel component force, for the sake of simplicity, it is assumed that either one of the forces acts in the following equation. It is clear from the following equation that skew can be detected even when the composite value of wheel pressures P _W and P _H acts. When the suspended load 22 is biased toward one end of the girder 2 when the crane is traveling, a speed difference is likely to occur between the driving wheels of the rocking leg 3 and the rigid leg 4, and therefore skewing is likely to occur. When skewing occurs, each wheel receives a vertical force due to the moment of the horizontal skewing force V generated by the skewing, and the wheel pressure changes. Thus, when a skew occurs, the aircraft experiences a torsional moment, and the vertical forces acting on each wheel are in opposite directions at each end of one leg. On the other hand, between the legs, the wheels at diagonal positions experience vertical forces in the same direction. Generally, the front wheel in the direction of travel of the leg on the side that is delayed receives a downward vertical force, and the wheel behind the leg in the direction of travel receives an upward vertical force. The wheels of the other leg experience vertical forces in the opposite direction. Therefore, if the wheel pressures of the wheels with load meters attached at both ends of one leg are compared, a difference in wheel pressure will occur between the two wheels when skew occurs. Skew is detected by a difference in the readings of the load cells on at least one of the rocking legs and the rigid legs. The wheels 6 and 7 are the wheels on which the load cell is attached on the rocking leg 3, the wheels 8 and 9 are the wheels on which the load cell is attached on the rigid leg 4, and _P6 is the resultant vertical force exerted on the wheel 6, that is, the wheel pressure; Let P ₇ , P ₈ , and P ₉ be the wheel pressures that the wheels 7, 8, and 9 receive, respectively. For the sake of explanation, it is assumed that the wheels 7 and 9 are on the east side, the wheels 6 and 8 are on the west side, the rigid leg 4 is on the south side, and the rocking leg 3 is on the north side. Due to the horizontal load W _P parallel to the girder, the pressure acting on the rocking leg 3 and the rigid leg 4 is W _P・H/L=±P _W Due to the horizontal load W _H perpendicular to the girder, the pressure acting on the rocking leg 3, The pressure that acts on the rigid leg 4 is: W _H・H/B=±PH The pressure that acts on the swinging leg 3 and the rigid leg 4 due to the oblique force _V generated during running is V・H/B= ± _PV Assuming that the number of wheels at one corner of each leg is n and the direction of the horizontal load is shown in Figure 3, the change in wheel pressure when skew occurs is expressed by the following equation. The wheel pressure of the wheels 6 and 7 of the rocking leg is a P ₆ = P ₁ −P _W /2n− _PV /n<P ₇ =P ₁ −P _W /2n+ _PV /n b P ₆ = P ₁ _-PH /2n- _PV /n<P ₇ =P ₁ + _PH /2n+ _PV /n When the direction of horizontal load W _H is opposite, c P ₆ = P ₁ + P _H /2n- _PV /n P ₇ = P ₁ - P _H /2n+P _V /n The wheel pressure of the wheels 8 and 9 on the rigid legs is a P ₈ =P ₂ +P _W /2n+P _V /n>P ₉ =P ₂ +P _W /2n-P _V /n b P ₈ =P ₂ -P _H /2n+ _PV /n P ₉ =P ₂ +P _H /2n-P _V /n c P ₈ =P ₂ +P _H /2n+ _PV />P ₉ =P ₂ -P _H /
2n-P _V /n In the above equation, it is impossible to compare the magnitudes of equation c in the case of a rocking leg and equation b in the case of a rigid leg. Therefore, the difference in wheel pressure between the rigid leg in state c and the rocking leg in state b is detected, and the traveling motor or traveling brake of the preceding leg is controlled to stop the skew. The combinations and controls are as shown in the table below.

【表】東行の時は輪圧P₈，P₉，P₆，P₇の夫々から検出
された荷重計検出値を比較器で比較し、P₈，P₇が
それぞれ増加した時に、制御装置によつて走行モ
ータ、走行ブレーキの少なくとも一方を制御する
ことにより、剛脚の先行した脚を遅らせる。P₆，
P₉が増加した時には、同様にして揺脚の先行した
脚を遅らせる。西行の時は東行と同様にして荷重計の検出する
輪圧変化を検出し、上表に従つて、所要の脚の先
行した側にモータ又はブレーキを作用して遅ら
せ、クレーンの斜行を防止する。前述の式においては、各脚の一方の側の１個の
車輪に荷重計を取付けるものとしたが、トラツク
１２に荷重計を取付ける場合の換算は容易であ
り、比較符号についての変化はない。本発明は簡単な荷重計を取付け、荷重の値を簡
単な回路によつて比較するため、著しく簡単な装
置であり、従来技術による複雑な構造を必要とせ
ずに、クレーンの斜行の検出と制御とを容易に行
なうことが可能となつた。[Table] When traveling east, the load meter detection values detected from wheel pressures P ₈ , P ₉ , P ₆ , and P ₇ are compared using a comparator, and when P ₈ and P ₇ increase, control is activated. By controlling at least one of the traveling motor and the traveling brake by the device, the leading leg of the rigid leg is delayed. _P6 ,
When P ₉ increases, the leading leg of the rocking leg is similarly delayed. When traveling westward, the change in wheel pressure detected by the load cell is detected in the same manner as when traveling eastward, and according to the table above, the motor or brake is applied to the leading side of the required leg to delay it and prevent the crane from moving diagonally. To prevent. In the above equation, it is assumed that a load cell is attached to one wheel on one side of each leg, but the conversion when a load cell is attached to the truck 12 is easy, and there is no change in the comparison sign. Since the present invention mounts a simple load cell and compares the load values using a simple circuit, it is an extremely simple device and can be used to detect crane skew without the need for the complicated structure of the prior art. It has become possible to easily perform control.

[Brief explanation of the drawing]

第１図は本発明を適用するクレーンの斜視図、
第２図は同じく側面図、第３図は同じく端面図、
第４図は第１〜３図のクレーンの部分拡大側面
図、第５図は第４図のＡ−Ａ線に沿う断面図であ
る。１……クレーン、２……桁、３……揺脚、４…
…剛脚、５……トラツク機構、６，７，８，９…
…車輪、１０，１１……レール、１２……トラツ
ク、１３……台車、１４……ピン、１５……軸
受、１６……車軸、１７……駆動歯車、２０……
荷重計、２１……トロリ、２２……吊荷。 FIG. 1 is a perspective view of a crane to which the present invention is applied;
Figure 2 is a side view, Figure 3 is an end view,
FIG. 4 is a partially enlarged side view of the crane shown in FIGS. 1 to 3, and FIG. 5 is a sectional view taken along line A--A in FIG. 4. 1... Crane, 2... Girder, 3... Rocking leg, 4...
...rigid leg, 5...track mechanism, 6, 7, 8, 9...
... Wheels, 10, 11 ... Rails, 12 ... Trucks, 13 ... Dolly, 14 ... Pins, 15 ... Bearings, 16 ... Axles, 17 ... Drive gears, 20 ...
Load cell, 21...trolley, 22...hanging load.

Claims

[Claims] 1. A skew prevention device for a crane having running wheels running on rails, a running motor, a running brake, and a trolley running across a girder, in which the wheel pressure of the plurality of running wheels is controlled. a detection means for detecting, a comparison means for comparing the magnitudes of the wheel pressures detected by the detection means, and a control device for controlling at least one of the travel motor and the travel brake according to the output of the comparison means. A crane skew prevention device characterized by comprising: 2. The crane skew prevention device according to claim 1, wherein a compression type load meter is used as the detection means.