JP2003238069A - Rail-clamp device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rail-clamp device usually allowing a crane to move on a rail, and holding the crane not to move only when strong wind occurs. <P>SOLUTION: The rail-clamp device 21 is provided with a rail-clamp mechanism 23 capable of switching a clamp condition and a clamp release condition, a rotary encoder 24 capable of detecting the movement of a container crane 1 on a rail 9, a control unit 25 controlling the rail-clamp mechanism 23 based on a detection result of the rotary encoder 24 when the movement of the container crane 1 is detected and the driving wheel 16 is not driven by the traveling motor 19. Thus, the rail-clamp mechanism 23 is usually held in a clamp release condition when an earthquake or a strong wind does not occur, however, the rail-clamp mechanism 23 is switched to a clamp condition only when the container crane 1 runs away the rail 9 by the occurrence of a strong wind or the like. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rail clamp device, and more particularly, to a device that keeps a crane movable on a rail under normal conditions and holds the crane immovable only in a specific condition such as strong wind. .

[0002]

2. Description of the Related Art For cranes that can travel on rails,
When the crane stops traveling, a strong wind (for example, a maximum of 35 m /
s) A rail clamp device for holding the crane in a traveling stopped state may be provided so that the crane does not move on the rail due to occurrence or the like. Although there are various types of rail clamp devices, for example, the rail is held by a pair of clamp arms by the elastic biasing force of the spring (in a clamped state), and the hydraulic cylinder is used to resist the elastic biasing force of the spring. The one configured to release the clamped state has been put into practical use.

The rail clamp device described above is switched between a clamped state and a unclamped state in conjunction with a traveling / stop command of the crane. In other words, the rail clamp device is in the clamped state when the crane is in the stopped state, and when the crane controller receives a traveling command from this state by the operation of the operator in the operator's cab, the controller releases the rail clamp device. After switching to the state, drive the traveling motor for traveling the crane. Conversely, while driving,
When the control device receives the crane stop command, the control device switches the rail clamp device to the clamp state after stopping the traveling motor and completely stopping the crane.
Since it takes 3 to 4 seconds to switch the rail clamp device between the clamped state and the unclamped state, it takes a considerable period of time from when the operator issues a traveling command until the crane actually starts traveling. (For example, 5 seconds) will be required.

Further, as described above, when the traveling of the crane is stopped, the rail clamp device is always in the clamped state. In this state, the crane is difficult to move in the traveling direction, and the rigidity of the crane in the traveling direction is high.
When a large-scale earthquake occurs, the vibration transmitted to the crane is hardly reduced and the crane may be damaged. To solve this problem, for example,
In the crane described in Japanese Patent Application Laid-Open No. 11-217189, a rail clamp device is provided on a leg portion of the crane, and a laminated rubber that absorbs vibration due to an earthquake or the like is interposed between the leg portion and the rail clamp device. There is.

[0005]

In the crane described in the above publication, even if an earthquake occurs while the traveling of the crane is stopped, the vibration transmitted to the crane can be reduced by the laminated rubber. However, as mentioned above,
If the rail clamp device is constantly clamped when the crane is in the stopped state, the crane will travel after a considerable amount of time has elapsed since the operator issued a travel command. In practice, operators often dislike this waiting time, and for this reason, the rail clamp device may be forcibly released from the unclamped state when the crane is in a stopped state.In such a case, There was a risk that the crane would escape due to a strong gust of wind. The object of the present invention is to reduce the waiting time from the travel command to the actual start of travel, to reduce the vibration transmitted to the crane at the time of an earthquake, to hold the clamp release state in the normal state, and to clamp only when strong wind occurs. To provide a rail clamp device that can be switched to a different state.

[0006]

A rail clamp device according to claim 1 is mounted on a crane traveling on a rail by a plurality of drive wheels driven by a traveling motor and a plurality of driven wheels, and the crane is in a traveling stopped state. In the rail clamp device held at, the rail clamp means capable of switching between the clamp state and the unclamped state, the movement detection means capable of detecting the movement of the crane on the rail, and the movement detection of the crane by the movement detection means. And a control means for controlling the rail clamp means based on the detection result of the movement detection means when the drive wheels are not driven by the traveling motor.

When the crane is moving on the rail, the movement is detected by the movement detecting means. Furthermore, when the crane is traveling normally on rails,
This is a state in which a plurality of drive wheels are driven by the traveling motor. Accordingly, when the movement of the crane is detected by the movement detecting means and the drive wheels are not driven by the traveling motor, the crane is moving on the rail by being swept by strong wind. In such a case, the control means can, for example, switch the rail clamp means to the clamped state to prevent the crane from moving on the rail. In addition, when strong winds are not generated, that is, when the movement of the crane is not detected by the movement detection means when the traveling motor is stopped, the rail clamp means is switched to the unclamped state, and the crane moves on the rail. Can be made movable.

According to a second aspect of the present invention, in the first aspect of the present invention, the control means controls the occurrence of an earthquake and a strong wind on the basis of a detection signal of the movement detection means when the traveling motor is stopped. It is characterized by having an earthquake occurrence detecting means and a strong wind occurrence detecting means for respectively detecting the occurrence. Therefore, when the earthquake occurrence detecting means detects the occurrence of the earthquake, the rail clamp means can be switched to the unclamped state, and when the strong wind occurrence detecting means detects the strong wind, the rail clamp means is switched to the clamped state. be able to.

According to a third aspect of the present invention, in the second aspect of the present invention, the control means holds the rail clamp means in an unclamped state during normal times when an earthquake or strong wind does not occur. It is a thing. Normally, since the rail clamp means is in the unclamped state, it is not necessary to operate the rail clamp means to the unclamped side when the operator issues a travel command, and the drive wheels can be immediately driven by the travel motor. become.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the control means holds the rail clamp means in an unclamped state even when an earthquake occurrence is detected by the earthquake occurrence detecting means. It is characterized by. Therefore, even when an earthquake is detected,
By holding the rail clamp means in the unclamped state, the crane can easily slide on the rail when an earthquake occurs, and the vibration transmitted to the crane can be reduced.

According to a fifth aspect of the present invention, there is provided the rail clamp device according to the third or fourth aspect, wherein the control means switches the rail clamp means to a clamped state when strong wind generation is detected by the strong wind generation detection means. It is characterized by. Therefore, when a strong wind is detected,
The rail clamp means can be switched to a clamped state to prevent the crane from moving due to strong wind.

According to a sixth aspect of the present invention, in the fifth aspect of the present invention, the control means includes the rail clamp means for a predetermined time when the strong wind generation detecting means detects a runaway of the crane. Is held in a clamped state, and thereafter, each time the strong wind occurrence detecting means detects a strong wind occurrence, the rail clamp means is held in the clamped state for the predetermined time.
When the strong wind occurrence detecting means detects the runaway of the crane due to the strong wind occurrence, the rail clamp means is switched to the clamp state, but since this state is maintained for a predetermined time by the control means, the strong wind is for a while. Even if it continues, the crane will not be washed away by the strong wind. After the lapse of a predetermined time, the rail clamp means is switched to the unclamped state, but each time the generation of a strong wind is detected thereafter, the rail clamp means is switched to the clamped state and held for the predetermined time.

According to a seventh aspect of the present invention, there is provided the rail clamp device according to any of the second to sixth aspects, wherein the earthquake occurrence detecting means reverses a moving direction of the crane for a predetermined short time when the traveling motor is stopped. It is characterized in that it is configured to detect the occurrence of an earthquake from. When an earthquake occurs, the crane will have its natural period (eg 3-4).
Since it stops or reverses the moving direction at intervals of about half of the second), when the traveling motor is stopped, for example,
Slip due to the occurrence of an earthquake can be detected by setting approximately half the natural period as the predetermined short time and detecting whether or not there is inversion during that period.

According to an eighth aspect of the present invention, in the rail clamp device according to any one of the first to seventh aspects, the movement detecting means includes:
When the crane moves on the rail, the crane comprises a rotary encoder connected to a rotation support shaft of an auxiliary wheel that comes into contact with the rail and is driven to rotate. The auxiliary wheels may be driven wheels of the crane, or may be wheels of the rail clamp device if the rail clamp device has wheels and is configured to be able to travel integrally with the crane. The movement of the crane can be detected by detecting the rotation of the auxiliary wheel with the rotary encoder.

[0015]

Embodiments of the present invention will be described with reference to the drawings. The present embodiment is an example in which the present invention is applied to a rail clamp device of a container crane that loads and unloads containers between a container yard on land and a container ship on the sea.

First, the container crane 1 will be briefly described. As shown in FIGS. 1 and 2, a container crane 1 includes a girder 2 that extends horizontally in the front-rear direction, a boom 3 that extends forward from the girder 2, a leg structure 4 that supports the girder 2 and the boom 3, and a left and right part. Two sets of traveling devices 5 are provided, two sets each. Container 6 is spreader 7
Is suspended by the trolley 8 and is transported by the trolley 8 along the girder 2 and the boom 3 in the front-rear direction for cargo handling.

Next, the traveling device 5 will be briefly described. Since the four sets of traveling devices 5 have the same structure, one set of traveling devices 5 will be described. As shown in FIGS. 2 and 3, the traveling device 5 for traveling on the rail 9 is
Rocker beam 10 connected to the lower end of leg structure 4
And two left and right balancers 11 connected to the lower end of the rocker beam 10, and tracks 12, 13, and 14 connected to the left and right two balancers 11, respectively.
A mooring anchor 15 is also provided between the left and right balancers 11.

Drive wheels 16 are provided on the truck 12,
The trucks 13 and 14 are provided with driven wheels 17 and 18, respectively. The drive wheels 16 and the driven wheels 17 and 18 cause the container crane 1 to travel on a rail 9. The truck 12 has a traveling motor 19 for driving the drive wheels 16 and a speed reducer 20.
Is also provided. A rail clamp device 21, which will be described later, is connected to the left track 12.

Next, regarding the rail clamp device 21,
This will be described with reference to FIGS. Rail clamp device 2
Reference numeral 1 denotes a container crane 1 which is mounted on the container crane 1 and holds the container crane 1 in a traveling stopped state, and is connected to two traveling devices 5 on the right side, as shown in FIG. Since the two rail clamp devices 21 have the same structure, one rail clamp device 21 will be described below. The rail clamp device 21 is connected to the container crane 1 and runs integrally with the truck 22, a rail clamp mechanism 23 (rail clamp means) capable of switching between a clamp state and a clamp release state, and a rail 9 of the container crane 1. A rotary encoder 24 (movement detecting means) capable of detecting upward movement, and a rail clamp mechanism 2
And a control unit 25 (control means) for controlling the control unit 3.

As shown in FIGS. 4 and 5, the truck 22 is connected to the left end portion of the truck 12 on the left side of the container crane 1 via a coupling member 30. This track 2
2 includes a pair of wheels 31 on the left and right, and when the container crane 1 moves on the rail 9, the wheels 31 make contact with the rail 9 and are driven to rotate, and the truck 22 is integrally railed with the container crane 1. Drive over 9. A rail clamp mechanism 23 is arranged at the center of the track 22 in the left-right direction.

As shown in FIGS. 4 to 7, the rail clamp mechanism 23 includes a pair of front and rear clamp arms 32 for gripping the rail 9 from the front and rear, and these clamp arms 32 are elastically attached to the rail grip side (clamp side). It has two urging clamp springs 33 and 34, and a single-acting hydraulic cylinder 35 that drives the clamp arm 32 to the rail grip release side (clamp release side).

As shown in FIGS. 4, 6 and 7, gripping portions 32a are formed at the lower end portions of the pair of clamp arms 32, and the upper end portions of the pair of clamp arms 32 are pin members 3.
6, and is connected to two pin members 38 via a link member 37. A fixed case member 3 is provided above the track 22.
9 is fixed, and a movable case member 40 that is vertically slidable with respect to the fixed case member 39 is also provided. Two pin members 38 are supported by the movable case member 40 from below.

A pair of left and right support plates 41 are also disposed on the left and right sides of the pair of clamp arms 32, and elongated holes 41a are formed in each support plate 41. One ends of the two pin members 38 are engaged with these elongated holes 41a, and the vertical movement of the pin members 38 is guided by the elongated holes 41a. The support member 4 is provided on the right side support plate 41.
Two detectors 44, 45 for detecting the unclamped state of the rail clamp mechanism 23 via 2, 43 are provided.
The movable case member 40 is also provided with a detected body 46 that is detected by the detectors 44 and 45.

Fixed case member 39 and movable case member 40
A spring accommodating chamber 47 is formed inside, and two springs 33 and 34 are arranged in the spring accommodating chamber 47. The hydraulic cylinder 35 has a cylinder body 35a and a rod 35b, the front end of the cylinder body 35a is connected to the upper end of the front clamp arm 32, and the rear end of the rod 35b is the upper end of the rear clamp arm 32. Are linked to.

The movable case member 40 includes springs 33 and 3.
4, the rail clamp mechanism 23 is constantly elastically urged upward, and when the rail clamp mechanism 23 is switched to the clamped state, the hydraulic pressure supply to the hydraulic cylinder 35 is stopped, the rod 35b advances, and the movable case member 40 moves upward. To do. At this time, since the pin member 38 also moves upward, the pair of clamp arms 32 are driven to the clamp side via the link member 37, and the grip portion 32a grips the rail 9. When the rail clamp mechanism 23 is switched to the unclamped state, hydraulic pressure is supplied to the hydraulic cylinder 35 so that the rod 35b is released.
Retracts, the pair of clamp arms 32 is driven toward the unclamping side against the elastic biasing forces of the springs 33 and 34, and the grip of the rail 9 is released.

As shown in FIGS. 4 and 5, the rotary encoder 24 is connected to the rotary support shaft 31a of the wheel 31 on the right side of the truck 22 and is covered with a cover member 48. When the container crane 1 moves on the rail 9, the wheels 31 also rotate, so that the rotation of the wheels 31 can be detected by the rotary encoder 24 to detect the movement of the container crane 1.

Next, the control unit 25 will be described with reference to FIG. Although not shown, the control unit 25 includes a CPU, a RAM, a ROM, an input / output interface, etc., which are connected by a bus. An earthquake occurred in the control unit 25 from the detected slip tendency of the container crane 1 based on the detection signal when the rotary encoder 24 detected the rotation of the wheels 31 when the traveling motor 19 was stopped. The earthquake occurrence detection means 28 for determining whether or not it is the same as the container crane 1
A strong wind occurrence detecting means 29 for determining whether or not a strong wind has occurred from the tendency of slippage is provided, and the earthquake occurrence detecting means 28 and the strong wind occurrence detecting means 29 are CPU and RA, respectively.
It is composed of M and ROM.

A signal from the operation panel 50 during manual operation, an encoder signal from the rotary encoder 24, a clamp release state detection signal from the detectors 44 and 45, etc. are input to the control unit 25. On the other hand, when switching the rail clamp mechanism 23 between the clamp state and the unclamp state, the oil passage switching valve 51 of the hydraulic system for the hydraulic cylinder is used.
To the hydraulic cylinder 35 to send a switching signal to the hydraulic cylinder 52.
The hydraulic pressure is supplied from or discharged from the hydraulic cylinder 35.

The control unit 25 is the container crane 1
Is also connected to the control device 60. This controller 60
A signal or the like from the operation panel 61 is input to the
The control device 60 includes a plurality of traveling motors 19 and a container 6
The signal is output to various devices such as a winding drum (not shown) that winds up. The control unit 25 receives an operation state signal of the traveling motor 19 from the control device 60, and as described later, when the traveling motor 19 is stopped, the earthquake occurrence detecting means 28 and the strong wind occurrence detecting means 29 cause occurrence of an earthquake or strong wind. Can be detected.

Next, the occurrence of an earthquake and the occurrence of a strong wind are detected by the earthquake occurrence detecting means 28 and the strong wind occurrence detecting means 29,
A control program of the rail clamp device 21 that switches the rail clamp mechanism 23 between the clamp state and the clamp release state will be described with reference to the flowcharts of FIGS. 9 and 10. Note that Si (i = 10, 11, 12, ...) Shows the step number. The rail clamp mechanism 23 is in the unclamped state in the initial state. In this state, as shown in FIG. 9, first, initialization processing such as clearing of RAM data is performed (S10), and an operation state signal of the traveling motor 19 and an encoder signal from the rotary encoder 24 are read (S1).
1).

When the traveling motor 19 is driven (S12: Yes), it means that the container crane 1 is traveling on the rail 9, so that the rail clamp mechanism 23 may remain in the unclamped state. Return and return to S10. If the traveling motor 19 is not driven (S1
2: No), rail clamp device 21 from encoder signal
If the wheels 31 of the container crane 1 are not rotating (S13: No), the container crane 1
Is not moving on the rail 9 and is in a normal time without occurrence of an earthquake or strong wind, the rail clamp mechanism 23 may remain in the unclamped state, and the process returns and returns to S10. When the wheel 31 is rotating (S13: Yes),
Since the container crane 1 is sliding on the rail 9, whether the slip is caused by an earthquake or strong wind is detected from the encoder signal by the earthquake occurrence detecting means 28 and the strong wind as shown below. Occurrence detection means 29
To determine.

First, since the flag Ft is initially 0 (S14: Yes), a timer T1 for integrating the rotation time of the wheels 31 (in FIG. 9, the integration time of the timer T1 is also shown as T1) is started ( In step S15, the flag Ft is set to 1 (S16), and the process proceeds to step S17. When the flag Ft is 1 (S14: No), since the timer T1 has already started, the process directly proceeds to S17. Next, when the rotation direction of the wheel 31 is reversed (S17: Yes), the number N of times the wheel 31 has been reversed since the timer T1 was started is increased by 1 (S18), and the process proceeds to S19. When the rotation direction of the wheel 31 is not reversed, the number N of times of reversal remains unchanged and the process proceeds to S19.

If the accumulated time of the timer T1 is equal to or less than a predetermined short time α (eg, α = 2.0 sec) which is about half the natural period of the container crane 1 (S19: No), T1 becomes α or more. Alternatively, the steps S11 to S18 are repeated until the traveling motor 19 is driven or the wheels 31 stop rotating. On the other hand, when the cumulative time of the timer T1 becomes α or more (S19: Yes), the wheel 3
If the rotation direction of 1 is reversed at least once (S20: Yes
), Since the moving direction of the container crane 1 is reversed, the earthquake occurrence detecting means 28 determines that an earthquake has occurred (S21), and holds the rail clamp mechanism 23 in the unclamped state (S22). , Return to S10.

If the rotation direction of the wheels 31 is not reversed within a predetermined time (S20: No), the container crane 1 is moving in the same direction on the rail 9, and therefore the strong wind generation detecting means 29. Determines that a strong wind has occurred (S2
3) Switch the rail clamp mechanism 23 to the clamped state (S24). Further, a timer T2 (in FIG. 10, the integration time of the timer T2 is also described as T2) for integrating the holding time of the clamped state is started (S25), and the timer T
The accumulated time of 2 is a predetermined time T0 (for example, T0 = 30 min)
The clamped state is maintained until the above (S26: No), and when the predetermined time T0 or more is reached (S26: Yes), the rail clamp mechanism 23 is switched to the unclamped state (S27), and the process returns and returns to S10.

That is, the rail clamp mechanism 23 is in the unclamped state during normal times when neither an earthquake nor strong wind occurs. Then, even when the earthquake occurrence detecting means 28 detects the occurrence of an earthquake, the rail clamp mechanism 23 is held in the unclamped state. On the other hand, only when the strong wind generation detecting means 29 detects the strong wind generation, the rail clamp mechanism 23 is switched to the clamped state and is held in the clamped state until a predetermined time T0 has elapsed. still,
After the elapse of the predetermined time T0, the rail clamp mechanism 23 is switched to the clamped state each time the strong wind generation detecting means 29 detects the strong wind, and the timer T2 is started until the predetermined time T0 elapses. The mechanism 23 is held in a clamped state.

According to the rail clamp device 21 described above, the following effects can be obtained. 1) Since the rail clamp mechanism 23 is held in the unclamped state during normal times when neither an earthquake nor strong wind occurs, the rail clamp mechanism 23 is unclamped when an operator issues a traveling command during such normal times. It is not necessary to switch to the state, and the drive wheels 16 are immediately driven by the traveling motor 19. Therefore, the waiting time from the travel command to the actual start of travel can be reduced.

2) Since the control unit 25 holds the rail clamp mechanism 23 in the unclamped state even when the earthquake occurrence detecting means 28 detects the occurrence of an earthquake, the container crane 1 can easily slide on the rail 9. The vibration transmitted to the container crane 1 during an earthquake can be reduced.

3) Since the control unit 25 switches the rail clamp mechanism 23 to the clamped state for a predetermined time T0 when the strong wind occurrence detecting means 29 detects the strong wind occurrence, the container crane 1 is operated when the strong wind occurs. It can be stopped. Further, since the rail clamp mechanism 23 is held in the clamped state for the predetermined time T0 every time the strong wind occurrence detecting means 29 detects the strong wind occurrence, the strong wind causes the container to move even when strong wind occurs for a long time or intermittently. The crane 1 never moves.

4) The earthquake occurrence detecting means 28 reverses the moving direction of the container crane 1 during a predetermined short time which is about half the natural period of the container crane 1 when the traveling motor 19 is stopped. Since the occurrence of an earthquake is detected from the presence or absence of the earthquake, it is possible to easily detect the occurrence of an earthquake even in various container cranes having different natural periods by changing the predetermined short time.

Next, a description will be given of a modified form in which various modifications are made to the above embodiment. 1] The rotary encoder 24 may be connected to any one of the rotation support shafts of the driven wheels 17 and 18 of the container crane 1 that comes into contact with the rails 9 and is driven to rotate when the container crane 1 moves. In this case, by detecting the rotation of the driven wheels 17 and 18 with the rotary encoder 24, the same operation and effect as those of the above-described embodiment can be obtained. 2) Even if the control unit 25 is configured to control the rail clamp mechanism 23 by detecting the occurrence of an earthquake or the occurrence of a strong wind by a signal from sensors such as an acceleration sensor that can detect the movement of the container crane 1. Good.

3] The wind speed is a predetermined value or more (for example, 16 m /
s or more), the rail clamp mechanism 23 is switched to the clamp state based on the signal from the anemometer, and the clamp is released based on the anemometer signal when the wind speed is a predetermined value or less (for example, 10 m / s or less). The rail clamp device 21 can also be configured to switch to the state. 4] The present invention is applicable to not only container cranes but also various types of cranes that travel on rails. Needless to say, the present invention can be applied to those which can be easily conceived by those skilled in the art based on the above-described embodiments without departing from the spirit of the present invention.

[0042]

According to the invention of claim 1, when the movement detecting means detects the movement of the crane and the traveling motor does not drive the drive wheels, the control means is based on the detection result of the movement detecting means. Since the rail clamp means is controlled, it is possible to prevent the crane from moving on the rail by switching the rail clamp means to the clamp state by the control means when the crane is moving on the rail due to strong wind or the like. In addition, when strong wind does not occur, the rail clamp means can be held in the unclamped state.In that case, when the operator issues a travel command, the rail clamp means is released in the unclamped state. The drive wheels are immediately driven by the traction motor without having to switch. Therefore, the waiting time from the travel command to the actual start of travel can be reduced.

According to the invention of claim 2, when the traveling motor is in a stopped state, the control means detects the occurrence of an earthquake and the occurrence of a strong wind, respectively, based on the detection signal of the movement detecting means. Since the device has the means and the strong wind generation detecting means, the vibration transmitted to the crane can be reduced by setting the rail clamp means to the unclamped state at the time of an earthquake. Further, when the strong wind occurrence detecting means detects the strong wind occurrence, the rail clamp means can be switched to the clamped state so that the crane does not move on the rail due to the strong wind. In addition, the same effect as that of the first aspect can be obtained.

According to the third aspect of the present invention, the rail clamp means is held in the unclamped state by the control means during normal times when no earthquake or strong wind is generated. Therefore, when the operator gives a running command during normal times, Since it is not necessary to switch the rail clamp means to the unclamped state, the drive motor immediately drives the drive wheels. Therefore, the waiting time from the travel command to the actual start of travel can be reduced. In addition, the same effect as that of the second aspect can be obtained.

According to the invention of claim 4, the control means holds the rail clamp means in the unclamped state even when the earthquake occurrence is detected by the earthquake occurrence detecting means.
By holding the rail clamp means in the unclamped state even when an earthquake occurs, the crane can move on the rail, so that the vibration transmitted to the crane can be reduced. In addition, the same effect as the third aspect can be obtained.

According to the fifth aspect of the present invention, the control means switches the rail clamp means to the clamp state when the strong wind occurrence detecting means detects the strong wind occurrence. Therefore, when the strong wind occurrence is detected, the rail The clamp means can be switched to the clamped state so that the crane does not move on the rail due to strong wind, and the rail clamp means can be held in the clamped state only when strong wind occurs. In addition, the same effect as that of claim 3 or 4 can be obtained.

According to the sixth aspect of the present invention, the control means holds the rail clamp means in the clamped state for a predetermined time when the strong wind generation detecting means detects the strong wind generation. Even if it continues, the strong wind will not move the crane. Further, thereafter, each time the strong wind occurrence detecting means detects the strong wind occurrence, the rail clamp means is held in the clamped state for the predetermined time,
Even if strong winds occur for a long time or intermittently, the cranes will not move due to the strong winds. In addition, the same effect as in claim 5 is obtained.

According to the invention of claim 7, the earthquake occurrence detecting means detects the occurrence of the earthquake from the reversal of the moving direction of the crane for a predetermined short time when the traveling motor is stopped. As the time is set to about half of the natural period and the presence or absence of inversion during that time is detected, the occurrence of an earthquake can be easily detected.
Further, it is possible to detect the occurrence of earthquakes of various cranes having different natural periods simply by changing the predetermined short time. In addition, the same effect as that of any one of claims 2 to 6 can be obtained.

According to the invention of claim 8, the movement detecting means comprises a rotary encoder connected to a rotation supporting shaft of an auxiliary wheel which comes into contact with the rail and is driven to rotate when the crane moves on the rail. The movement of the crane can be detected by detecting the rotation of the auxiliary wheel with the rotary encoder. In addition, the same effect as that of any one of claims 1 to 7 can be obtained.

[Brief description of drawings]

FIG. 1 is a side view of a container crane according to an embodiment of the present invention.

FIG. 2 is a front view of a container crane.

FIG. 3 is a front view of a traveling device.

FIG. 4 is a front view of a rail clamp device.

5 is a view taken along the line VV of FIG.

FIG. 6 is a side view of a rail clamp mechanism.

FIG. 7 is a plan view of FIG.

FIG. 8 is a block diagram of a container crane and a rail clamp device.

FIG. 9 is a flowchart showing a control system of the rail clamp device.

10 is the remainder of the flowchart of FIG.

[Explanation of symbols]

1 container crane 9 rails 16 drive wheels 17,18 Driven wheel 19 traveling motor 21 Rail clamp device 23 Rail clamp mechanism 24 rotary encoder 25 control unit

Claims (8)

[Claims] 1. A rail clamp device equipped on a crane that travels on a rail by a plurality of driving wheels driven by a traveling motor and a plurality of driven wheels, and holds the crane in a stopped state. When the movement of the crane is detected by the movement detection means and the drive wheels are not driven by the traveling motor, rail clamp means that can be switched to the state, movement detection means that can detect movement of the crane on the rail A rail clamp device, further comprising: a control unit that controls the rail clamp unit based on a detection result of the movement detection unit. 2. The control means, when the traveling motor is in a stopped state, based on a detection signal of the movement detection means,
The rail clamp device according to claim 1, further comprising an earthquake occurrence detecting means and a strong wind occurrence detecting means for detecting occurrence of an earthquake and occurrence of a strong wind, respectively. 3. The rail clamp device according to claim 2, wherein the control means holds the rail clamp means in an unclamped state during normal times when an earthquake or strong wind does not occur. 4. The rail clamp device according to claim 3, wherein the control means holds the rail clamp means in an unclamped state even when an earthquake occurrence is detected by the earthquake occurrence detecting means. 5. The control means switches the rail clamp means to a clamped state when strong wind generation is detected by the strong wind generation detection means.
Or the rail clamp device according to 4. 6. The control means holds the rail clamp means in a clamped state for a predetermined time when the strong wind occurrence detecting means detects the strong wind occurrence, and then the strong wind occurrence detecting means detects the strong wind occurrence. 6. The rail clamp device according to claim 5, wherein the rail clamp means is held in a clamped state for each of the predetermined times each time. 7. The earthquake occurrence detecting means is configured to detect an earthquake occurrence by reversing the moving direction of the crane for a predetermined short time when the traveling motor is stopped. The rail clamp device according to any one of to 6. 8. The movement detecting means comprises a rotary encoder connected to a rotation support shaft of an auxiliary wheel which comes into contact with the rail and is driven to rotate when the crane moves on the rail. The rail clamp device according to any one of 1 to 7.