An overhead crane equipped with a mechanism to absorb errors in the running rail installation

Abstract

To provide an overhead crane with an absorption mechanism of a travelling rail laying error capable of driving a top run-type overhead crane on the rail whose laying accuracy of an overhead crane travelling rail exceeds a permissible value.SOLUTION: A top run-type overhead crane that the crane runs on the top surface of travelling rails has a configuration that a tie-in part of one saddle 13b of two pairs of saddles of the overhead crane and of a crane girder 12 is a fixing structure, a tie-in part of the other saddle 13a and of the crane girder 12 is provided with a movable part using a spherical bearing 31, and that the crane can follow the travelling rail lying error while maintaining the crane structure by providing side rollers 17 at the bottom of the saddle 13a where the movable part is provided.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an overhead crane equipped with a mechanism for absorbing errors in the installation of the traveling rails of the crane. [Background technology]

[0002] The accuracy of the rail installation of the crane's running rails gradually deteriorates over time due to distortion of the building, subsidence of the ground, misalignment of the rail installation fasteners, etc. For this reason, the accuracy of the rail installation is regularly measured and corrected to maintain and manage it, but if the distortion of the building or subsidence of the ground is excessive, it can be difficult to keep the rail installation accuracy within the allowable values. If a crane runs on the two running rails on both sides of an overhead crane when the accuracy errors in the installation of the running rails, such as the span dimensions, rail undulation (horizontal curvature), rail gradient, etc., exceed the allowable values, it can cause malfunctions such as abnormal wear on the treads and flange surfaces of the crane's running wheels and the running rails, damage to the running bearings, and cracks in the crane girders and saddles.

[0003] To address this issue, cranes have been proposed that are equipped with mechanisms that absorb errors in the laying of traveling rails so that the cranes can run normally even on traveling rails where the rail laying accuracy exceeds the standard (see, for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-228474 [Patent Document 2] JP 2008-179428 A [Patent Document 3] JP 2010-202357 A [Patent Document 4] Utility Model Registration No. 3152371 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the mechanisms for absorbing errors in laying the traveling rails disclosed in Patent Documents 1 to 4 are all intended for suspended overhead cranes that hang from the traveling rails, and structurally, it is difficult to create a robust overhead crane. On the other hand, in a top-run overhead crane, which has a robust structure in which the crane is stacked against gravity on top of the running rails, if a mechanism is used to absorb errors in the laying of the running rails similar to that of a suspended overhead crane that hangs along with gravity, the joint between the crane girder and the saddle will bend, causing the saddle to collapse into a diamond shape, making it impossible to maintain the crane structure. In consideration of this problem, the present invention aims to provide a top-run type overhead crane equipped with a mechanism for absorbing errors in the installation of the traveling rails, enabling the overhead crane to run on rails where the installation accuracy of the traveling rails exceeds the allowable value. [Means for solving the problem]

[0006] In order to solve the above problems, the overhead crane equipped with a mechanism for absorbing installation errors of the traveling rail of the present invention is a top-run type overhead crane in which the crane runs on the top surface of the traveling rail, and of the two sets of saddles of the overhead crane, the joint between one saddle and the crane girder is fixed, and the joint between the other saddle and the crane girder is provided with a movable part using a spherical bearing, and side rollers are provided under the saddle with the movable part, thereby The structure is characterized by being able to accommodate errors in the installation of the running rails while maintaining the structure of the rail. As a result, one side of the interface between the saddle placed on the running rail and the crane girder stacked on top of it is firmly fixed, while the other side is made a movable structure using a spherical bearing.By doing so, it is possible to absorb rail installation errors by allowing the movable part provided by the spherical bearing to move, even in cases where the installation accuracy of the running rails is significantly off, such as span errors between the left and right running rails, undulations of the running rails, and slope of the running rails.

[0007] In other words, by adopting a spherical bearing in the structure of one side of the saddle and the movable part of the crane girder, the movable saddle can move freely in three dimensions relative to the crane girder. Horizontal side rollers are provided under the movable saddle to allow the saddle to follow and move in accordance with the installation error of the traveling rail, and the side rollers also restrain the saddle in the horizontal direction against any movement of the saddle that tends to tip over from the vertical position, thereby preventing the saddle from tipping over. The top-run overhead crane, which is stacked against gravity, can maintain its shape without losing its shape by having a saddle on one side that is firmly fixed to the crane girder, a saddle that can move freely due to an absorption mechanism, and a side roller attached to the lower part of the movable saddle that exerts a horizontal restraining force. At this time, any error in the traveling rail on the side where the saddle is fixed to the crane girder is transmitted from the saddle on the traveling rail through the crane girder which is firmly fixed to the saddle to the movable part provided at the joint with the saddle on the opposite side, and the laying error of the traveling rail is absorbed by this movable part.

[0008] In this case, by using a metal bush in addition to using a spherical bearing in the movable portion, it is possible to increase the amount of error absorption in the span direction. In addition to using spherical bearings for the moving parts, metal bushings are used for the bearings of the running wheels, and a sliding mechanism in the span direction is provided on the running wheels, thereby making it possible to increase the amount of error absorption in the span direction. When dimensional errors such as span errors are absorbed by a spherical bearing structure alone, the movable saddle is angled to absorb them. However, when the dimensional error in the span direction is large, the use of a metal bush in combination with the spherical bearing increases the horizontal range of movement of the saddle in the span direction, thereby expanding the range in which rail errors can be absorbed. This not only reduces the angle of inclination of the movable saddle, but also reduces the horizontal force applied to the side rollers under the saddle. Furthermore, in addition to the spherical bearing portion, metal bushings can be inserted into the bearing portions of the running wheels to allow the running wheels to move horizontally in the span direction, thereby absorbing errors in the horizontal span direction of the rail. Effect of the Invention

[0009] According to the overhead crane equipped with the mechanism for absorbing installation errors of the traveling rails of the present invention, even if there is an error in the installation of the traveling rails in a top-run type overhead crane that exceeds the installation accuracy standard, the crane girder, saddle, traveling wheels, or traveling rails will not bear the allowable load from the traveling rail side. This reduces cracks in the crane, abnormal wear on the flanges of the traveling wheels, and wear on the traveling rails, allowing the overhead crane to operate stably. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory diagram of an overhead crane equipped with a mechanism for absorbing errors in laying the traveling rails. [Diagram 2] FIG. 4 is an explanatory diagram of the clearance between a traveling rail and a traveling wheel. [Diagram 3] FIG. 13 is a detailed structural explanatory diagram of a mechanism for absorbing errors in rail installation using spherical bearings. [Figure 4] FIG. 13 is a detailed structural explanatory diagram of a mechanism for absorbing errors in the installation of running rails that uses a spherical bearing and a metal bush in combination. [Diagram 5] This is a structural explanatory diagram illustrating a span horizontal direction absorption mechanism provided by using metal bushings for the running wheel bearings. [Figure 6]FIG. 13 is a diagram for explaining the function of the present invention with respect to absorbing span error. [Figure 7] 10A and 10B are diagrams for explaining the operation of the present invention with respect to absorbing lateral height errors of the traveling rails. [Figure 8] 10A and 10B are diagrams for explaining the operation of the present invention with respect to absorbing a difference in gradient between the left and right sides of a traveling rail. [Figure 9] 4A to 4C are diagrams for explaining the operation of the present invention with respect to absorbing swells (horizontal bending) of a traveling rail. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an overhead crane equipped with a mechanism for absorbing errors in laying a traveling rail according to the present invention will be described based on an embodiment with reference to the drawings.

[0012] FIG. 1 shows the appearance of a top-run type overhead crane equipped with a mechanism 10 for absorbing errors in laying a traveling rail according to the present invention. A top-run overhead crane is constructed in such a way that a running rail 15 is laid on top of a runway girder 16 attached to pillars on both sides of the building, the saddle of the overhead crane is placed on top of that, and the crane girder 12, which is firmly fixed at right angles to the saddle, is stacked on top of that. A hoist or crab 11 equipped with a hoisting device and a traverse device is attached to the crane girder 12, forming a basic configuration in which the hoist or crab 11 moves traversely across the crane girder 12.

[0013] In the conventional structure, the crane girder 12 and saddle are firmly fixed with high-strength bolts or the like, and the installation error of the traveling rail 15 was conventionally absorbed by the clearance dimension 19 between the traveling rail 15 and the traveling wheels 14 shown in Figure 2. Conventionally, the installation accuracy standard of the traveling rail was set so that it was within the range that could be absorbed by the clearance dimension 19, and by observing this standard, the overhead crane was able to travel smoothly. However, in areas where the building has been significantly distorted due to ground subsidence or the like, it is not possible to meet the installation accuracy standards, and with the structure of conventional overhead cranes, problems such as early abnormal wear on the sides of the running wheel flanges 18 and the running rails 15, and cracks in the crane girder 12 and saddle parts have occurred.

[0014] In the present invention, for a crane installed on a traveling rail 15 with a laying error that exceeds the standard for accuracy in laying the traveling rail, a mechanism 10 for absorbing the running rail laying error is provided on the overhead crane side, so that the overhead crane can travel smoothly even on a traveling rail with a large laying error. In this case, in a suspended overhead crane structure that hangs down along with gravity, a mechanism for absorbing errors in the installation of the traveling rails can be easily installed between the saddle and the crane girder; however, if the same structure as a suspended overhead crane is used in a top-run overhead crane, which is constructed so that the traveling rails are stacked upwards against gravity, the crane will collapse into a diamond shape. Therefore, in the top-run type overhead crane of the present invention, as shown in Figure 1, one saddle (fixed side) 13b and the crane girder 12 are firmly fastened at a right angle with high-strength bolts or the like, and a movable part is provided between the other saddle (movable side) 13a and the crane girder 12 with a mechanism 10 for absorbing laying errors of the traveling rail, allowing the saddle (movable side) 13a to move. The side of the traveling rail 15 is pressed horizontally by side rollers 17 at the bottom of the saddle (movable side) 13a, allowing the saddle (movable side) 13a to flexibly follow deviations in the installation accuracy of the traveling rail, while at the same time restricting the saddle (movable side) 13a from falling in the vertical direction Y by the traveling rail installation error absorption mechanism 10. The combination of the crane girder 12, saddle (fixed side) 13b, saddle (movable side) 13a, and side rollers 17 constitutes a rigid top-run type overhead crane, preventing the shape of the crane from collapsing. do.

[0015] 3, the mechanism 10 for absorbing installation errors of the traveling rail incorporates a spherical bearing 31, and a housing 33 on the outer ring side of the spherical bearing 31 is incorporated into an upper bracket 32, which is joined to the crane girder 12 with a high-strength bolt or the like. A pin 35 is fitted into the inner ring side of the spherical bearing 31, which is fixed to a lower bracket 34, and the lower bracket 34 is joined to the saddle (movable side) 13a with a high-strength bolt or the like. This allows the saddle (movable side) 13a to move relative to the crane girder 12 in a tilting θ1 direction, a rotation θ2 direction, and a swing θ3 direction. In addition, in order to ensure easy replacement of the spherical bearing 31, which is a consumable part, the upper bracket 32 ​​and the crane girder 12, and the lower bracket 34 and the saddle (movable side) 13a are structured so that they can be attached and detached by bolting.

[0016] In the structure of FIG. 3, in order to absorb errors in the horizontal span direction X, etc., the saddle (movable side) 13a tilts in the direction θ1. However, if the tilt θ1 becomes too large, the horizontal force of the side roller 17 becomes too strong. Therefore, when the error in the horizontal span direction X, etc., is excessive, after a stopper that restricts the amount of tilt of the saddle (movable side) 13a within a certain range is activated, a metal bush 37 is added to the spherical bearing 31 portion as shown in FIG. 4, and the metal bush 37 portion slides horizontally by a slide dimension 38 that corresponds to the gap dimension between the spherical bearing 31 and the collar 36. This ensures an absorption width for errors in the horizontal span direction X and the like while suppressing the amount of inclination of the saddle (movable side) 13a, thereby making it possible to keep the horizontal force of the side roller 17 low.

[0017] Furthermore, the horizontal sliding mechanism in the horizontal span direction using a metal bush can be used in combination with the spherical bearing 31 shown in FIG. 4, or the same effect can be obtained by using a metal bush 39 for the running wheel in the bearing portion of the running wheel 14 shown in FIG. 5. The method of employing the metal bushing 39 for the running wheels is such that a gap of a running wheel slide dimension 40 is provided between the saddle frame and the running wheels 14, thereby allowing the running wheels 14 to slide in the horizontal direction. By sliding the running wheels horizontally in the span running direction in this way, the horizontal force of the side rollers 17 can be kept low by ensuring an absorption width for errors in the span horizontal direction X, etc. while suppressing the amount of inclination of the saddle (movable side) 13a.

[0018] The operation of this mechanism for absorbing rail laying errors will now be described. First, when an error ±C occurs in span S from the state shown in Fig. 6(1) to the state shown in Fig. 6(2), the alignment of the spherical bearing 31 of the traveling rail installation error absorption mechanism 10 causes a tilt θ1 in the saddle (movable side) 13a, making it possible to absorb the span error of the traveling rail. The horizontal force generated when the tilt θ1 occurs in the saddle (movable side) 13a is borne by the side roller 17. The allowable span error C is determined by the strength of the side roller 17 and the allowable alignment angle of the spherical bearing 31, but in addition, if the tilt angle of the saddle (movable side) 13a becomes too large, the structure of the crane cannot be maintained, so there is only a small degree of accuracy in tilting, and a stopper is used to restrain the tilt angle so that it does not become too large. In this case, if the allowable range of the span error C is to be expanded beyond that caused by the tilting of the saddle (movable side) 13a, a structure using a spherical bearing 31 and a metal bush 37 in combination as shown in FIG. 4, or a structure using a metal bush 39 for the traveling wheel in combination with the traveling wheel as shown in FIG. 5, is used. In this way, by providing a mechanism 10 for absorbing installation errors of the running rail, wear of the running wheel flanges 18 and damage to the running wheel bearings, wear on the side of the running rail 15, cracks in the saddle, etc., caused by span error C that exceeds the running rail installation accuracy standard are eliminated.

[0019] Next, even if a horizontal difference h occurs in the running rail from the state shown in FIG. 7(1) to the state shown in FIG. 7(2), the spherical bearing 31 of the running rail installation error absorption mechanism 10 can be aligned to absorb the horizontal difference h. A tilt θ1 occurs in the saddle (movable side) 13a, making it possible to absorb the horizontal difference h of the running rail 15. In this case as well, the horizontal force generated when the tilt θ1 occurs in the saddle (movable side) 13a is borne by the side rollers 17. The allowable horizontal difference h of the running rail is determined by the strength of the side rollers 17 and the allowable alignment angle of the spherical bearing 31, but in addition to that, if the allowable range of the allowable horizontal difference h of the running rail is to be widened, a structure in which the spherical bearing 31 and metal bush 37 are used in combination as shown in Figure 4, or a structure in which the running wheel metal bush 39 is used in combination with the running wheel as shown in Figure 5, can be adopted.

[0020] When a gradient occurs from the state of Figure 8 (1) to the state of Figure 8 (2) and a gradient difference occurs between the left and right traveling rails 15, the spherical bearing 31 of the traveling rail installation error absorption mechanism 10 rotates in the direction of rotation θ2, dissipating the torsional force so that the crane girder 12 does not twist even if a gradient difference occurs between the left and right traveling rails. In a conventional structure not equipped with the mechanism 10 for absorbing installation errors of the traveling rails, the combined force of the twisting of the crane girder 12 due to the difference in gradient between the left and right sides and the bending due to the load of the suspended load is applied to the crane girder 12, significantly affecting fatigue deterioration of the crane girder 12 and causing cracks in the crane girder 12. The mechanism 10 for absorbing installation errors of the traveling rails eliminates the twisting of the crane girder 12 and is effective in reducing crack accidents.

[0021] As shown in Figure 9, when a swell (horizontal bend) U occurs in the running rail 15 and the equilibrium state of the left and right rails is locally disturbed to form a V-shape or an inverted V-shape, the saddle (movable side) 13a swings in the swing direction θ3 along the swell (horizontal bend) of the running rail 15 due to the movement of the spherical bearing 31 of the running rail installation error absorption mechanism 10 and the pressure of the side rollers 17, so that the saddle (movable side) 13a moves along the running rail in the swing direction θ3. In response to the swell (horizontal bending) U that occurs in the running rail on the saddle (fixed side) 13b side, the saddle (fixed side) 13b swings along the swell (horizontal bending) U of the running rail 15, and the crane girder 12, which is firmly fixed perpendicular to the saddle (fixed side) 13b, swings due to the swing of the saddle (fixed side) 13b. Since the spherical bearing 31 of the mechanism 10 for absorbing installation errors of the running rail between the crane girder 12 and the saddle (movable side) 13a gives an angle to the swing θ3, the saddle (fixed side) 13b can move and follow the swell (horizontal bending) U of the running rail 15 even if it wobbles.

[0022] As described above, in the present invention, in which a top-run type overhead crane is equipped with a mechanism 10 for absorbing errors in laying the traveling rails, the mechanism 10 for absorbing errors in laying the traveling rails is provided only on one side between the crane girder 12 on one side and the saddle (movable side) 13a, and not on the saddle (fixed side). However, since the laying errors in the traveling rails 15 that affect the overhead crane are caused by the relative laying errors of the left and right traveling rails 15, the mechanism 10 for absorbing errors in laying the traveling rails can be provided in one of the two saddles, and the rail error absorption function can be satisfied, even if it is not provided on both the left and right saddles.

[0023] The above is the basic action of the present invention, but in reality, span errors, left and right height differences, and left and right gradient differences occur three-dimensionally and are compounded, and the traveling rail installation error absorption mechanism 10 of the present invention can absorb traveling rail errors three-dimensionally. In other words, since it is possible to release forces in three axial directions, it is possible to avoid problems such as abnormal wear on the treads and flange surfaces of the crane's traveling wheels, damage to traveling bearings, and cracks in the saddle of the crane girder 12, due to traveling rail errors from all directions.

[0024] The overhead crane equipped with a mechanism for absorbing errors in laying a traveling rail according to the present invention has been described above based on its embodiment, but the present invention is not limited to the configuration described in the above embodiment, and the configuration can be changed as appropriate within the scope of the gist of the present invention. . [Industrial Applicability]

[0025] With the overhead crane equipped with the mechanism for absorbing the installation error of the traveling rail of the present invention, even if a top-run type overhead crane is installed on the traveling rail of an old building that exceeds the standard value of the installation accuracy of the traveling rail, it is possible to prevent abnormal wear of the tread and flange surfaces of the traveling wheels of the crane, damage to the traveling bearings, and cracks in the crane girder and saddle, thereby making it possible to extend the life of the crane and improve its reliability. In addition, it is possible to reduce the frequency of repairs to the traveling rail and the building, so it can be effectively used in industry. [Explanation of symbols]

[0026] 10. Mechanism for absorbing errors in the construction of running rails 11 Whist, Clubs 12 Crane girder 13a Saddle (movable side) 13b Saddle (fixed side) 14 Running wheels 15 Running rail 16 Runway Guard 17 Side roller 18 Running wheel flange 19 Clearance dimensions 31 Spherical bearing 32 Upper bracket 33 Housing 34 Lower bracket 35 pin 36 Color 37 Metal Bush 38 Slide dimensions 39 Metal bushing for running wheels 40 Traveling wheel slide dimensions X-span horizontal Y vertical direction Z Travel horizontal direction S span C Span Error h Horizontal difference between left and right rails α gradient difference U swell (horizontal bend) θ1 Fall θ2 rotation θ3 Runout

Claims

1. This overhead crane is equipped with a mechanism for absorbing errors in the laying of the traveling rails, and is characterized in that the joint between one of the saddles of the overhead crane's two sets of saddles and the crane girder is fixed, and the joint between the other saddle and the crane girder is provided with a movable part comprising an upper bracket joined to the underside of the crane girder with bolts, a lower bracket joined to the upper surface of the saddle with bolts, and a spherical bearing incorporated between the upper bracket and the lower bracket, and side rollers are provided under the saddle on which the movable part is provided, thereby enabling the crane to follow up on errors in the laying of the traveling rails while maintaining the structure of the crane.

2. 2. An overhead crane equipped with a mechanism for absorbing errors in the installation of a traveling rail as described in claim 1, characterized in that a metal bush that is slidable in the span direction along the pin of the spherical bearing of the movable part is provided, thereby increasing the amount of error absorption in the span direction.

3. 2. An overhead crane equipped with a mechanism for absorbing errors in laying the traveling rails as claimed in claim 1, characterized in that the bearings of the traveling wheels of the crane are provided with metal bushes that allow the traveling wheels to slide in the span direction, thereby increasing the amount of error absorption in the span direction.

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