JP3609041B2 - Isolation structure of container crane - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to container clayNThe present invention relates to seismic isolation structures, and in particular, to those that can be isolated at the time of an earthquake with a small number and simple structure.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, various types of cranes such as bridge cranes and portal cranes are used to handle various loads such as containers. For example, as illustrated in FIG. 8, a container crane that is used when cargo is handled between a container yard and a container ship on land and is a type of portal crane will be described. A horizontal girder 102 and a undulating boom 103 extending in the front-rear direction (direction connecting the land and the sea) for moving between land and ship for cargo handling, and a leg structure 104 for supporting the girder 102 and the boom 103. The four sets of traveling devices 105 that travel on the rails of the container yard are connected to the lower end of the leg structure 104, and the container crane 100 can move in the container yard by the traveling devices 105. In the girder 102 and the boom 103, a trolley 107 that holds the container 101 suspended by a rope via a spreader 106 is movable in the front-rear direction, and the container crane 100 moves the trolley 107 between the container yard and the container ship. The container 101 is unloaded.
[0003]
By the way, the leg structure 104 is composed of a pair of left and right surfaces, each of which is a horizontal connection that connects a pair of front and rear column members 108 and lower portions of the pair of front and rear column members 108. The member 109 and the diagonal member 110 that connects the connecting portion between the column member 108 and the horizontal connecting member 109 and the upper end portion of the column member are configured. Since the girder 102 and the boom 103 have a long structure in the front-rear direction and the leg structure 104 is easily bent, the slanting material 110 and the like increase the rigidity in the front-rear direction of the container crane 100. For this reason, in the normal use state of the container crane 100, the girder 102 and the boom 103 are not easily shaken, and the container 101 can be stably handled. However, due to the high rigidity, the natural vibration period is short (1 to 2 seconds), and the container crane In general support ground of, there is a period that is relatively close to the dominant period of vibration at the time of earthquake, so when strong shaking occurs in the front-rear direction due to the earthquake, it tends to fall into resonance and occurs in each part of the structure There is a problem that the stress and the reaction force of the structure support portion become large.
[0004]
In order to solve the above problem, various seismic isolation structures have been proposed. For example, in the container crane described in JP 2000-143153 A, a seismic isolation device having a laminated rubber is provided between the leg structure of the crane and the traveling device.
[0005]
[Problems to be solved by the invention]
In the container crane of the above publication, since it is necessary to provide a seismic isolation device for all traveling devices, a large number of seismic isolation devices are required, and furthermore, to provide a seismic isolation device between the leg structure and the traveling device, The structure of the seismic isolation device is complicated, and the seismic isolation device needs to be strong enough to support the entire crane structure above the traveling device.
The object of the present invention is to be able to withstand the strong vibration of the ground during an earthquake with a small number of simple structure.containerIt is to provide a seismic isolation structure for the crane.
[0006]
[Means for Solving the Problems]
Claim 1containerThe seismic isolation structure of the crane is a horizontal girder,With undulating boom,GirderAnd boomWith leg structure to supportcontainerIn the seismic isolation structure of a crane, the leg structure includes a left side structure and a right side structure that are connected to each other, and each surface connects a pair of front and rear column members and lower portions of the column members. A horizontal connecting member, and a pair of diagonal members that connect a middle portion in the longitudinal direction of the horizontal connecting member to the upper end portions of the front and rear column members, and the upper end portions of the pair of front and rear column members are 1 or A seismic isolation mechanism that is connected to each other through a plurality of members and is provided at a connecting portion that connects a diagonal connecting portion and a horizontal connecting member that connect the lower end portions of a pair of diagonal members in each of the structural surfaces. ,Laminated rubber in which multiple layers of metal plates and rubber are alternately laminated, andLeft-right movement restricting means that allows relative movement in at least the front-rear direction between the diagonal member coupling portion and the horizontal connecting member and restricts relative movement in at least the left-right directionAnd at least the forward and backward movement restricting means for restricting at least the forward and backward relative movement between the diagonal member coupling portion and the horizontal connecting member and releasing the restriction of the forward and backward relative movement under a predetermined condition when an earthquake occurs, and the horizontal connection And an upward movement restricting means for restricting the relative movement of the diagonal member joint with respect to the member, and configured to reduce the longitudinal rigidity in the composition plane and increase the natural period of the container crane in the event of an earthquake. WasIt features a seismic isolation mechanism.
[0007]
containerclayNThe leg structure is composed of a pair of front and rear column members, a horizontal connection member that connects lower portions of the column members, and a horizontal connection member and an upper end portion of the column member on each of the left and right surface structures. By the pair of diagonal materials, the rigidity is increased in the front-rear direction (the direction connecting the land and the sea). The upper ends of the pair of front and rear column members are connected to each other via one or a plurality of members. In addition, although the connection method of the upper end parts of a pair of column members before and after each construction surface may be directly connected by providing one member, in container cranes, the upper ends of the pair of left and right column members on the front side Provided are a front upper left and right connecting member that connects each other, and a rear upper left and right connecting member that connects the upper ends of a pair of left and right pillar members on the rear side. By fixing an extending horizontal girder, the upper ends of a pair of column members in front and rear of each construction surface are often connected. Each structural surface thus configured is mechanically stable and has high rigidity in the front-rear direction.
[0008]
The principle of seismic isolation allows relative movement between the structure and the ground and makes it difficult for vibrations of the ground to be transmitted to the structure, but causes relative movement between the structure and the ground and restores it. There are many seismic isolation mechanisms with power. When the seismic isolation mechanism is provided in this way, the natural period of the entire structure including the seismic isolation mechanism is made as long as possible from the resonance point by making the natural period of the structure support ground as long as possible. This reduces the amplitude of acceleration that is separated and consequently excited in the structure. When the seismic isolation mechanism functions according to the principle of seismic isolation, the stress generated in each part of the structure and the reaction force of the structure support during an earthquake can be reduced.
[0009]
Therefore,leftIn each right construction surface, relative to at least the front-rear direction between the diagonal member connecting portion and the horizontal connecting member is connected to the connecting portion connecting the diagonal member connecting portion connecting the lower ends of the pair of diagonal members and the horizontal connecting member. By providing a seismic isolation mechanism that allows movement, the longitudinal longitudinal period of the crane is increased by reducing the longitudinal rigidity in the construction surface, and the seismic isolation function works according to the principle of seismic isolation. is there.
[0010]
The seismic isolation mechanism may be provided at one position in the middle of the horizontal connecting member (preferably near the center as much as possible). Accordingly, the seismic isolation mechanism is provided at the intersection of the two front and rear diagonal members and one horizontal connecting member, that is, at the intersection of the truss structure. As is apparent from structural mechanics, only the longitudinal shearing force is generated as the basic stress, which has the advantage that the design of the seismic isolation mechanism is facilitated. Of course, in reality, other stresses are also generated, but these are secondary stresses that are small in value and do not significantly affect the design of the seismic isolation mechanism. If the seismic isolation mechanism is provided at the connecting portion between the lower end portion of one diagonal member 110 and the horizontal connecting member 109 in the conventional leg structure of the crane as shown in FIG. Since the axial force of 110 is transmitted as it is, a large stress acts on the seismic isolation mechanism not only in the front-rear direction but also in the vertical direction, so that the structure of the seismic isolation mechanism becomes complicated and has to be strong. Since such a main stress in the vertical direction is not generated in the seismic isolation mechanism according to the first aspect of the invention, the structure of the seismic isolation mechanism can be simplified, and the natural period of the longitudinal direction of the crane can be reduced with a small number of seismic isolation mechanisms. It can be isolated long enough.
[0011]
In addition, since the seismic isolation mechanism includes left and right movement restricting means for restricting relative movement in at least the left and right direction between the diagonal member coupling portion and the horizontal connecting member, the diagonal material coupling portion is displaced horizontally in the horizontal direction. It does not come off from the connecting member. Note that the relative movement in the left-right direction in this case may be regulated so that the amount of relative movement in the left-right direction does not exceed the allowable range for the structure.
[0012]
[0013]
Of this container craneThe seismic isolation mechanism has laminated rubber in which multiple layers of metal plates and rubber are laminated alternately.For the nextIt has the characteristics of.
EarthThe seismic isolation mechanism functions by allowing the laminated rubber to be deformed in the horizontal direction at the time of the earthquake and allowing relative movement in at least the front-rear direction between the diagonal member joint and the horizontal connecting member.
productSince the rubber layer can have a relatively large horizontal restoring force by appropriately selecting the elastic modulus, shape, and dimensions, the pair of front and rear diagonal members in the longitudinal direction of the entire left and right construction surface according to the restoring force It can function as a shear force transmission element. Accordingly, the size of the pair of column members in the front and rear of each of the left and right surfaces can be reduced as compared with the case of the seismic isolation mechanism that does not have a restoring force with respect to the relative movement in the horizontal direction.
[0014]
productSince the rubber layer is not deformed more than a predetermined amount, excessive relative movement between the diagonal member connecting portion and the horizontal connecting member can be prevented.above,Since usually used laminated rubber has a large damping performance, the seismic isolation mechanism also has a damping function.
Also,Since normally used laminated rubber has a relatively large restoring force, the laminated rubber returns to its original state when the vibration is stopped. That is, the relative positional relationship between the diagonal member connecting portion and the horizontal connecting member generated during the earthquake can be automatically returned to the original state when the earthquake ends.Moreover,Since the laminated rubber also has a restoring force in the left-right direction, taking into account the restoring force and the characteristics of the laminated rubber that does not deform more than a predetermined amount, the left-right direction between the diagonal connecting portion and the horizontal connecting member When the relative movement amount can be regulated by the laminated rubber within a structurally safe range, the laminated rubber itself may be used as the left / right movement regulating means.
[0015]
Of this container craneThe seismic isolation mechanism is provided with a forward / backward movement restricting means that restricts at least the forward / backward relative movement between the diagonal member coupling portion and the horizontal connecting member at all times and cancels the restriction of the forward / backward relative movement under a predetermined condition.Therefore, the following action is obtained.
[0016]
If a crane is provided with a seismic isolation mechanism, the crane's longitudinal rigidity will decrease, making it easier for the crane to swing during normal use of the crane than without a seismic isolation mechanism and hindering smooth cargo handling operations. For this reason, it is always desirable that the crane has high rigidity. However, since it is necessary to make the seismic isolation mechanism function during an earthquake, the forward / backward movement restricting means always restricts the relative movement in the front / rear direction at least to maintain the crane's longitudinal rigidity at a high level. The cargo handling operation is made possible, and when a large earthquake occurs and a predetermined condition is reached, the regulation of the relative movement in the front-rear direction is canceled and the seismic isolation mechanism functions. In addition, “when a predetermined condition is reached” refers to any item selected from the load generated by an earthquake (or the stress at a designated location on the crane), the vibration acceleration at the ground or designated location on the crane, or the seismic intensity of the earthquake. It is preferable that the value is equal to or greater than a predetermined value.
Since the upward movement restricting means for restricting the upward relative movement of the diagonal member connecting portion with respect to the horizontal connecting member is provided, the upward relative movement of the oblique member connecting portion with respect to the horizontal connecting member is restricted.
This seismic isolation device is configured to reduce the longitudinal rigidity in the longitudinal direction of the construction plane and increase the natural period of the longitudinal direction of the container crane when an earthquake occurs. Can be reliably prevented.
[0017]
A seismic isolation structure for a container crane according to claim 2 is characterized in that, in claim 1, the seismic isolation mechanism also has a damping function. In general, the vibration of a structure excited by an external excitation force has a smaller amplitude (that is, vibration damping performance increases) as the structure damping performance increases. Therefore, the damping performance of the entire structure should be as large as possible. desirable. Accordingly, the damping performance of the entire crane can be increased by providing the seismic isolation mechanism also with a damping function.  Claim3 containersThe seismic isolation structure of the crane is claimed1The forward / backward movement restricting means is a shear pin. The shear pin is designed to be sheared and broken when a load exceeding a predetermined value is applied. The diagonal connecting part and the horizontal connecting member are connected with a shear pin, and the relative movement in the front-rear direction is restricted at all times. When a large earthquake occurs and a load exceeding a specified level is applied to the shear pin, the shear pin shears and breaks. Thus, the restriction on the relative movement in the front-rear direction is released, and the seismic isolation mechanism functions to increase the natural period in the front-rear direction of the crane.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described. In the present embodiment, the present invention is applied to a container crane that is a typical example of a portal crane. As shown in FIG. 1, the container crane 2 includes a horizontal girder 3 extending in the front-rear direction, a undulating boom 4, and a leg structure 5 that supports the girder 3 and the boom 4. A container 6 is unloaded between 1 and a container ship (not shown) at sea.
[0019]
First, the girder 3 and the boom 4 will be described.
As shown in FIG. 1, at the position of the upper end of the column member 40 of the leg structure 5, the rear end of the boom 4 is rotatably connected to the front end of the girder 3. It is erected. Also in the middle of the girder 3 in the length direction, the rear upper structure 12 is erected at the position of the upper end of the column member 41 of the leg structure 5. Diagonal members 13, 14, 15 extend from the upper end of the front upper structure 11 to the girder 3 and the boom 4, and oblique members 16, 17 extend from the upper end of the rear upper structure 12 to the girder 3. As a result, the girder 3 and the boom 4 are maintained in a horizontal posture.
[0020]
A machine room 18 is provided at the rear part of the girder 3. In this machine room 18, a hoisting drum 19 for raising and lowering the boom 4, a hoisting drum (not shown) for raising and lowering the spreader 24, and a trolley 26 are moved back and forth. A trolley driving drum (not shown) for driving is disposed. The boom 4 has a rope 21 connected to the hoisting drum 19 through the sheave 20, and the boom 4 performs hoisting operation by winding or unwinding the rope 21 with the hoisting drum 19.
[0021]
Next, the leg structure 5 will be described.
As shown in FIG. 2, the leg structure 5 includes a left side surface 30 and a right side surface 31 that are connected to each other. The upper ends of the composition surfaces 30 and 31 are connected by a pair of upper left and right connection members 36 and 37, and the lower ends of the composition surfaces 30 and 31 are also connected by a pair of lower left and right connection members 38 and 39. A pair of left and right traveling devices 34 are connected to the connecting members 38 and 39, respectively.
[0022]
Since the left side construction surface 30 and the right side construction surface 31 are bilaterally symmetrical and similarly configured, the right side construction surface 31 will be described. As shown in FIG. 1, the right side construction surface 31 includes a pair of front and rear column members 40 and 41, a horizontal connection member 42 that connects lower portions of the column members 40 and 41, and the length of the horizontal connection member 42. A diagonal member coupling that includes a pair of diagonal members 43 and 44 that connect a middle part in the direction (however, a substantially intermediate point) to the upper end portions of the front and rear column members 40 and 41 and that joins the lower end portions of the diagonal members 43 and 44. A seismic isolation mechanism 46 is provided at a connecting portion that connects the portion 45 and the horizontal connecting member 42. Further, the upper end portion of the front column member 40 of the right side construction surface 31 is connected to the front upper left and right connecting member 36, and similarly, the upper end portion of the rear side column member 41 of the right side construction surface 31 is connected to the rear upper left and right connection member 36. The pair of upper left and right connecting members 36 and 37 connected to the member 37 are connected to each other by the girder 3, so that the upper end portions of the column members 40 and 41 on the right side construction surface 31 are connected to the girder 3 and the upper part. The left and right connecting members 36 and 37 are connected to each other. The right construction surface 31 is configured in this way to form a mechanically stable construction surface. As is clear from structural mechanics, in the case of such a configuration, the seismic isolation mechanism 46 provided at the connecting portion between the diagonal member connecting portion 45 and the horizontal connecting member 42 can be separated by a small amount of secondary stress. Basically, only the horizontal shear load in the front-rear direction acts, and the load in the vertical direction does not act.
[0023]
Next, the seismic isolation mechanism 46 will be described.
As shown in FIGS. 3 to 7, the seismic isolation mechanism 46 includes a laminated rubber 50 having a damping function by alternately laminating metal plates and rubber, a guide member 54 (right and left movement restricting means), and a shear pin 55 (front and rear). Movement restriction means). The laminated rubber 50 has a high compressive strength, can be easily deformed in the horizontal direction, and does not deform more than a predetermined amount. The metal plate 50a at the upper end of the laminated rubber 50 is bolted to the metal plate 51 fixed to the lower end of the diagonal member coupling portion 45, and the metal plate 50b at the lower end of the laminated rubber 50 is bolted to the metal plate 52. 52 is fixed to the horizontal connecting member 42 via a holding plate 53. Therefore, the laminated rubber 50 is fixed between the horizontal connecting member 42 and the diagonal member coupling portion 45. When a large vibration is transmitted to the leg structure 5 of the container crane 2 due to an earthquake or the like, the laminated rubber 50 is deformed in the front-rear direction.
[0024]
A pair of guide members 54 fixed to the horizontal connecting member 42 are provided on the left and right sides of the laminated rubber 50, and the guide member 54 is erected on the horizontal connecting member 42 and the horizontal member 54 a held in a horizontal posture. It is comprised with the two vertical support members 54b which support the horizontal member 54a. As shown in FIG. 7, the inner surface of the horizontal member 54 a (the surface on the diagonal material coupling portion 45 side) is outside the locking member 51 a erected on the metal plate 51 fixed to the lower end of the diagonal material coupling portion 45. It is in contact with the side. The left and right ends of the metal plate 51 are in contact with the lower surface of the horizontal member 54a.(This structure corresponds to the upward movement restricting means for restricting the upward relative movement of the diagonal member coupling portion 45 to the horizontal connecting member 42.)The right end portion of the metal plate 51 and the right horizontal member 54 a are connected by a shear pin 55. The shear pin 55 is to be sheared and broken by a load in the front-rear direction that is greater than or equal to a predetermined value, and the laminated rubber 50 can be deformed in the front-rear direction through the breakage of the shear pin 55, and the seismic isolation mechanism 46 functions.
[0025]
When the shear pin 55 is sheared and broken by a load in the front-rear direction that is greater than or equal to a predetermined value, the laminated rubber 50 is deformed in the front-rear direction so that the diagonal member coupling portion 45 is relatively relative to the horizontal connecting member 42 as shown in FIG. It can move in the front-rear direction. However, in the left-right direction, the guide member 54 restricts the relative movement of the diagonal member coupling portion 45 in the left-right direction with respect to the horizontal connecting member 42.
[0026]
Next, the effect | action of the seismic isolation structure of the container crane 2 is demonstrated.
In the normal use state of the container crane 2, as shown in FIG. 3, the diagonal member coupling portion 45 is restricted from moving relative to the horizontal coupling member 42 by the shear pin 55 that couples the metal plate 51 and the horizontal member 54 a, and the container crane 2 The rigidity in the front-rear direction is maintained. Therefore, when the container 6 is unloaded between the container yard 1 and the container ship, the leg structure 5 is not easily bent, and the container 6 can be unloaded stably.
[0027]
When vibration occurs on the ground due to an earthquake or the like, the vibration is transmitted to the leg structure 5. A shear load in the front-rear direction acts on the shear pin 55 due to the transmitted vibration. However, when the vibration is small and the load is equal to or less than a predetermined value, the shear pin 55 is not broken, and the container crane 2 has high rigidity in the front-rear direction. Vibrates while holding. When the vibration transmitted to the leg structure 5 is large and the load is greater than or equal to a predetermined value, the shear pin 55 undergoes shear failure.
[0028]
When the shear pin 55 is sheared and broken, the connection between the metal plate 51 and the guide member 54 is cut, that is, the restriction of the relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connection member 42 is released, and the laminated rubber 50 is Deformable in the front-rear direction. Accordingly, the longitudinal rigidity of the left and right structural surfaces 30 and 31 is reduced, the longitudinal natural vibration period of the container crane 2 is increased (for example, 3 seconds or more), and the vibration at the time of earthquake in the general support ground of the container crane 2 is increased. The seismic isolation function of the seismic isolation structure works by becoming longer than the dominant cycle. Further, since the damping performance due to horizontal deformation of the laminated rubber 50 is large, the damping coefficient in the longitudinal vibration of the entire left and right structural surfaces 30 and 31 is increased, and the laminated rubber 50 also provides a vibration damping effect.
[0029]
At this time, the laminated rubber 50 does not deform more than a predetermined amount in the horizontal direction due to its characteristics, and therefore, the laminated rubber 50 does not deform more than a predetermined amount in the front-rear direction. Further, as shown in FIG. 7, since the inner side surface (the surface on the diagonal member coupling portion 45 side) of the horizontal member 54a is in contact with the outer surface of the locking member 51a, the diagonal member coupling portion 45 and the horizontal connecting member 42 is restricted from moving in the left-right direction, and the diagonal member coupling portion 45 does not come off the horizontal connecting member 42 in the left-right direction. Further, as described above, the seismic isolation mechanism 46 provided at the connecting portion between the diagonal member connecting portion 45 and the horizontal connecting member 42 basically has a horizontal shear in the front-rear direction except for a small secondary stress. Although only a load is applied, even if a vertical tensile force is applied to the seismic isolation mechanism 46 as a secondary stress, the metal plate 51 fixed to the lower end of the diagonal member coupling portion 45 is attached to the guide member 54. Since the upward movement is locked by contacting the lower surface of the horizontal member 54a, the vertical force between the diagonal member coupling portion 45 and the horizontal connecting member 42 is not opened, and a tensile force acts on the laminated rubber 50. There is nothing.
[0030]
According to the above-described seismic isolation structure of the container crane 2, the seismic isolation mechanism 46 is connected to the diagonal members 43 and 44 at the left and right construction surfaces 30 and 31, and the horizontal connection member 45. Since it is provided in the connecting portion that connects with 42, it is possible to obtain a sufficient seismic isolation effect at the time of an earthquake only by providing a relatively simple structure and one seismic isolation mechanism 46 on each of the left and right sides.
[0031]
The seismic isolation mechanism 46 includes a laminated rubber 50, a guide member 54, and a shear pin 55. The elastic vibration of the laminated rubber 50 in the front-rear direction causes the natural vibration period in the front-rear direction of the container crane 2 to be appropriately long, thereby providing a seismic isolation function. In addition, the damping performance of the laminated rubber 50 can increase the longitudinal damping coefficient of the entire leg structure 5 to provide a damping effect on the longitudinal vibration. If a laminated rubber in which a lead plug is embedded is used, a greater damping performance can be obtained due to plastic deformation of the lead plug.
[0032]
Further, the laminated rubber 50 is deformed in the front-rear direction, but is not deformed more than a predetermined amount, so that the amount of relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 may be larger than a predetermined amount. Therefore, it is possible to prevent the relative movement from becoming excessively unexpected and the entire leg structure 5 from becoming unstable. Further, due to the high resilience of the laminated rubber 50, the relative position in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 returns to the original state after the earthquake ends, so that the container crane 2 after the earthquake ends Recovery work becomes easier.
[0033]
Since the shear pin 55 connects the right end of the metal plate 51 fixed to the lower end of the diagonal connecting portion 45 and the horizontal member 54a of the pair of guide members 54 fixed to the horizontal connecting member 42, the diagonal is always used. The relative movement in the front-rear direction between the coupling portion 45 and the horizontal connecting member 42 is restricted, and the rigidity in the front-rear direction of the container crane 2 can be kept high so that a stable cargo handling operation can be performed. When a strong vibration is transmitted to the container crane 2 due to an earthquake and a load exceeding a predetermined value is applied to the shear pin 55, the shear pin 55 is sheared and broken, and the restriction of the relative movement in the front-rear direction is released. Elastic deformation is possible, and the effect of seismic isolation by the seismic isolation mechanism 46 occurs.
[0034]
In the guide member 54, the inner side surface (the surface on the diagonal material coupling portion 45 side) of the horizontal member 54 a is in contact with the outer surface of the locking member 51 a erected on the metal plate 51 fixed to the lower end of the diagonal material coupling portion 45. Because of the contact, the relative movement of the diagonal member coupling portion 45 and the horizontal coupling member 42 in the left-right direction is restricted, and the diagonal member coupling portion 45 is not displaced in the horizontal direction from the horizontal coupling member 42, thereby stabilizing the leg structure 5. Is preserved. Further, as shown in FIG. 7, the metal plate 51 fixed to the lower end of the diagonal member coupling portion 45 is in contact with the lower surface of the horizontal member 54a.ProductA tensile force does not act on the layer rubber 50.
[0035]
Next, modified embodiments obtained by adding various modifications to the embodiment will be described.
1] As a seismic isolation mechanism, a linear guide (linear motion bearing) that allows relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 and that can restrict relative movement in the left-right direction is used. Also good. In this case, the lower part of the linear guide is fixed to the horizontal connecting member 42, and the member connected to the diagonal member coupling portion 45 is configured to slide in the front-rear direction while being restricted from moving in the left-right direction within the linear guide. Since the linear guide does not have a restoring force, various members such as a spring that can be elastically deformed in the front-rear direction may be added if necessary.
[0036]
2) If the left and right rigidity of the laminated rubber 50 is sufficient to restrict the relative movement in the left and right direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 within a predetermined amount, the relative movement in the left and right direction is reduced. The laminated rubber 50 may be configured to be elastically deformable in the left-right direction by omitting the guide member 54 for restriction. In this case, the method of attaching the shear pin 50 is different from the method of attachment in the above embodiment, but it can be processed in any way as a design matter.
[0037]
3] It is possible to provide a seismic isolation mechanism that does not generate a restoring force when a relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 occurs. That is, an elastically deformable member such as the laminated rubber 50 and the spring is not provided in the seismic isolation mechanism, and for example, the diagonal member coupling portion 45 is configured to be slidable in the front-rear direction relative to the horizontal connecting member 42. In this case, since the diagonal members 43 and 44 do not function as diagonal members for transmitting a shearing force, the required strength of the left and right structural surfaces 30 and 31 is increased by increasing the strength of the pair of front and rear column members 40 and 41. It is necessary to secure.
[0038]
4] The shear pins 55 that connect the metal plate 51 and the guide member 54 are not limited to one, and a plurality of shear pins 55 may be provided on the left and right of the metal plate 51. From the relationship between the predetermined load at which the shear pin 55 is to be sheared and the shear fracture strength of one shear pin, the number of shear pins 55Can be variously selected.
[0039]
5) In the seismic isolation mechanism, the relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 is normally regulated by a regulating member (for example, a lock pin), and the seismic isolation is performed by an external electric signal under a predetermined condition. The mechanism is instructed to release this restriction, and upon receiving this instruction, the restriction member is driven to the restriction release side by driving means such as an electric motor to release the restriction on the relative movement in the front-rear direction. Also good. As the electrical signal, acceleration from the seismometer, seismic intensity information, or the like can be used.
[0040]
6] A damping function may be provided by providing a hydraulic damper cylinder in the seismic isolation mechanism. In this case, the hydraulic damper cylinder is arranged with its axial direction aligned with the longitudinal direction of the container crane 2, the tube of the hydraulic damper cylinder is fixed to the horizontal connecting member 42 side, and the tip of the rod of the hydraulic damper cylinder is diagonal. The vibration of the container crane 2 can be damped by being fixed to the coupling portion 45 side and expanding and contracting the rod in accordance with the relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42.
[0041]
7] When a hydraulic damper cylinder is provided as described above, a hydraulic unit with a relief function is connected to the hydraulic damper cylinder, and the relief valve is normally closed to restrain the rod of the hydraulic damper cylinder from expanding and contracting, The seismic isolation mechanism may be configured such that the relief valve is opened and the rod expands and contracts when the hydraulic pressure in the hydraulic damper cylinder becomes a positive pressure higher than a predetermined value or a negative pressure lower than a predetermined value. In this case, since the expansion and contraction of the rod of the hydraulic damper cylinder is normally restricted, the relative movement in the front-rear direction between the diagonal member coupling portion 45 and the horizontal connecting member 42 is restricted, and the rigidity in the front-rear direction of the crane is kept high. At the same time, when a shearing force in the front-rear direction acts between the diagonal member coupling portion 45 and the horizontal connecting member 42 due to an earthquake, the shearing force is transmitted to the hydraulic damper cylinder, and the hydraulic pressure increases or decreases depending on the direction of the shearing force. The relief valve in the hydraulic unit is opened when the hydraulic pressure rise or fall amount exceeds a predetermined level, and the expansion / contraction restriction of the rod of the hydraulic damper cylinder is released. Let
[0042]
8] The present invention can also be applied to a portal crane other than a container crane, a bridge crane, such as a club trolley crane, a bridge crane for shipbuilding, and the like. In addition, it goes without saying that the present invention can be applied to the above-described embodiment and modifications thereof without departing from the spirit of the present invention.
[0043]
【The invention's effect】
According to the invention of claim 1,containerIn a crane, a seismic isolation mechanism provided at a connecting portion that connects a diagonal connecting portion connecting a lower end portion of a pair of diagonal members and a horizontal connecting member on each surface of a leg structure, Since the seismic isolation mechanism provided with the left and right movement restricting means for permitting at least the relative movement in the front-rear direction and at least the left and right direction relative movement between the first and second horizontal connecting members is provided, the following effects are obtained.
[0044]
When a large vibration is generated on the ground due to an earthquake, the vibration is transmitted to the leg structure. In the seismic isolation mechanism provided at the connecting part of the diagonal connecting part and the horizontal connecting member, Relative movement at least in the front-rear direction with respect to the horizontal connecting member is allowed, the natural vibration period in the front-rear direction of the crane is lengthened, and the seismic isolation function works according to the principle of seismic isolation.
leftThe right movement restricting means restricts the relative movement in at least the left and right direction between the diagonal member coupling portion and the horizontal connecting member, so that the diagonal member coupling portion does not deviate from the horizontal connecting member in the left and right direction, and the leg portion. Structural stability is maintained. The seismic isolation mechanism only needs to be provided on each of the left and right surfaces of the leg structure, and since only the shearing force in the front-rear direction acts as the main load, the structure of the seismic isolation mechanism can be simplified. Moreover, a sufficient seismic isolation effect can be realized by a small number of seismic isolation mechanisms.
[0045]
[0046]
Also,Since the seismic isolation mechanism has a laminated rubber in which multiple layers of metal plates and rubber are laminated alternately, the restoring force of the laminated rubber works against the relative movement in the horizontal direction between the diagonal joint and the horizontal connecting member, Compared to the case where the seismic isolation mechanism does not have a restoring force, the size of the pair of pillar members in the front and rear of the left and right surface can be reduced. In addition, when the earthquake ends, the horizontal relative positional relationship between the diagonal member joint and the horizontal connecting member can be automatically restored to the original state automatically by the restoring force of the laminated rubber. Recovery becomes easy. Further, the laminated rubber is not deformed more than a predetermined amount in the horizontal direction, and an excessive relative movement in the front-rear direction between the diagonal member coupling portion and the horizontal connecting member can be prevented. Furthermore, the vibration transmitted to the crane can be controlled by the high damping performance of the laminated rubber..
[0047]
Also,The seismic isolation mechanism is always provided with a forward / backward movement restricting means that restricts at least the forward / backward relative movement between the diagonal member joint and the horizontal connecting member, and releases this restriction under a predetermined condition.And an upward movement restricting means for restricting the upward relative movement of the diagonal member connecting portion with respect to the horizontal connecting member.The forward / backward movement restricting means always restricts the relative movement in the front / rear direction between the diagonal member coupling portion and the horizontal connecting member, and the crane's longitudinal rigidity is maintained at a high level, thereby enabling smooth cargo handling work at all times. In addition, since the restriction is released only when a predetermined condition is satisfied due to the occurrence of a large earthquake, a relative movement in the front-rear direction is generated between the diagonal member connecting portion and the horizontal connecting member, thereby causing the crane to move in the front-rear direction. The natural vibration period can be lengthened and can be isolated.
[0048]
According to the invention of claim 2, since the seismic isolation mechanism also has a damping function, the seismic isolation mechanism makes the natural vibration period longer in the front-rear direction and performs the seismic isolation, and increases the longitudinal damping performance of the crane. It is also possible to control the vibration. In addition, the same effects as those of the first aspect can be obtained.
Claim3According to the invention, since the shear pin is used as the forward / backward movement restricting means, at least the relative movement in the front / rear direction between the diagonal member coupling portion and the horizontal connecting member is always restricted by the shear pin, so that a smooth cargo handling operation at all times can be performed. In addition, when a load more than the specified value due to an earthquake acts on the shear pin, the shear pin may shear and break, allowing relative movement in the front-rear direction and lengthening the natural vibration period in the front-rear direction of the crane for seismic isolation. it can. Other claims1The same effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a front view of a container crane according to an embodiment of the present invention.
FIG. 2 is a side view of a container crane.
FIG. 3 is a front view of the seismic isolation mechanism (normal use state).
FIG. 4 is a view of the seismic isolation mechanism taken along line IV-IV.
FIG. 5 is a cross-sectional view of the seismic isolation mechanism taken along line VV.
Fig. 6 is a cross-sectional view of the seismic isolation mechanism taken along line VI-VI (when shear pin is broken)
FIG. 7 is an enlarged cross-sectional view of the main part of the seismic isolation mechanism (near the shear pin).
FIG. 8 is a front view of a conventional container crane.
[Explanation of symbols]
2 Container crane
3 Girder
5 Leg structure
30 Left side surface
31 Right side composition
40 Front column member
41 Rear column member
42 Horizontal connecting members
43,44 diagonal
45 Diagonal material joint
46 Seismic Isolation Mechanism
50 Laminated rubber
54 Guide members
55 Share Pin

Claims (3)

A horizontal girder, and relief type boom, the seismic isolation of a container crane and a leg structure supporting the girder and the boom,
The leg structure includes a left side construction surface and a right side construction surface connected to each other,
Each construction surface has a pair of front and rear column members, a horizontal connection member that connects lower portions of the column members, and a pair that connects a middle portion in the length direction of the horizontal connection member to the upper ends of the front and rear column members. The upper end portions of the pair of front and rear column members are connected to each other via one or a plurality of members, and are connected to the lower end portions of the pair of diagonal members in each of the structural surfaces. A seismic isolation mechanism provided in a connecting portion for connecting the material connecting portion and the horizontal connecting member,
Laminated rubber in which multiple layers of metal plates and rubber are laminated alternately;
With allowing at least the longitudinal direction of the relative movement between the diagonal member coupling portion and the horizontal connecting member, and the lateral movement restricting means for restricting a relative movement of at least the lateral direction,
A front-rear movement restricting means for restricting at least the front-rear relative movement of the diagonal member coupling portion and the horizontal connecting member at all times, and releasing the restriction of the front-rear relative movement under a predetermined condition when an earthquake occurs;
An upward movement restricting means for restricting the upward relative movement of the diagonal member coupling portion with respect to the horizontal connecting member,
A seismic isolation structure for a container crane, which is provided with a seismic isolation mechanism configured to increase the longitudinal natural period of the container crane by reducing the longitudinal rigidity in the frame when an earthquake occurs . Seismic Isolation of Kontenaku lanes according to claim 1, wherein the seismic isolation mechanism, characterized in that it also has a damping function. The seismic isolation structure for a container crane according to claim 1 , wherein the front-rear movement restricting means is a shear pin.

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