JP2009113925A - Overhead crane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overhead crane capable of preventing floating of a crane body when an earthquake occurs, without anxiety of damaging a crane girder. <P>SOLUTION: A body side magnet is provided in the crane body 10, and a girder side magnet is provided in the crane girder 14. When the earthquake occurs, the body side magnet and the girder side magnet attract with each other to push the crane body 10 to a traveling rail 16. In this case, the body side magnet is an electromagnet 26 provided in a second bottom part 10b of the crane body 10, and the girder side magnet is a row of magnetic poles 24 of electromagnets installed side by side at fixed pitch in a moving direction of the crane body 10 in a side part 14a of the crane girder 14. The electromagnet 26 and the row of the magnetic poles 24 are opposed with a prescribed space. As a result, the crane body 10 can be avoided from colliding with the crane girder 14 without floating by making the electromagnet 26 and the electromagnets of the row of the magnetic poles 24 opposed to the electromagnet 26 into mutually attracting states at the earthquake, for instance. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an overhead crane, and more particularly to an overhead crane that suppresses the crane body from being lifted or horizontally swayed when an earthquake occurs to prevent damage to a crane girder or the like.

  5 and 6 show a conventional overhead crane. FIG. 5A is a schematic plan view, and FIG. 5B is a schematic cross-sectional view. Crane girders 14 are installed in pairs on both sides of the upper part of the building housing 12. A traveling rail, which will be described later, is installed at the upper end of the crane girder 14, and the crane body 10 is configured to be movable in the direction indicated by the arrow A in FIG. Usually, the power for moving the crane body 10 is an electric motor or the like (not shown).

  FIG. 6A is an enlarged cross-sectional view of a main part of the portion indicated by arrow B in FIG. The figure (b) is an expanded sectional view of a crane girder. As described above, the crane girder 14 is installed on the upper part of the building housing 12, and the traveling rail 16 is installed on the upper end of the crane girder 14. The crane body 10 is thin on both sides on the crane girder 14 side for attaching the wheels 18, and therefore constitutes a first bottom portion 10 a and a second bottom portion 10 b, and the first bottom portion 10 a and the second bottom portion. There is a step between 10b. And the crane main body 10 is comprised so that a movement on the above-mentioned traveling rail 16 using the wheel 18 attached to the 1st bottom part 10a is possible.

  As shown in FIG. 6B, the crane girder 14 is made of H steel or the like, and side portions 14a are provided on both sides of the upper end portion 14b on which the traveling rail 16 is laid, as will be described later. In addition, the side portion 14a is useful for preventing the crane body portion 10 from falling off or derailing.

  A derailment prevention lug 20 is provided on the second bottom portion 10 b of the crane body 10. The derailment prevention lug 20 is provided with a protrusion 20a that is hooked on the side 14a of the crane girder 14 so that the crane body 10 may drop or derail due to vibration or shaking during an earthquake. It is prevented.

  Generally, the vibration is amplified as you go to the top of a building during an earthquake. Since the crane main body 10 is often installed near the ceiling, the derailment prevention lug 20 attached to the crane main body 10 is restrained by being caught by the crane girder 14 at the time of vibration of a large earthquake. However, since a vibration such as a strong vertical movement occurs in a large earthquake, a phenomenon that the crane body 10 itself is lifted occurs. Therefore, there is a concern that the crane girder 14 will have insufficient proof stress and have adverse effects on the structure such as damage. More specifically, in the event of a large earthquake, the crane body 10 is lifted, the protrusion 20a of the derailment prevention lug 20 collides with the side portion 14a of the crane girder 14, and the crane body 10 is dropped or derailed. Although it can be avoided, the side portion 14a may be deformed or cracked, and the crane girder 14 may be damaged.

  In the existing general crane equipment, when a strong vertical vibration is generated due to an earthquake, the drop-out prevention lug 20 attached to the crane body 10 prevents the derailment / drop-off. There are no facilities that take measures to prevent adverse effects on structures such as girders.

  In such a situation, in Patent Document 1, a crane main body extending in the left-right direction is bridged via a traveling wheel on left and right traveling rails extending in the front-rear direction fixedly supported on the building side via a rail mount. A shroud case is provided on the rail mount in the overhead crane so as to surround the movement trajectory of the wheel frame that supports the traveling wheel, and the wheel frame in the shroud case is sandwiched by the left and right to reach almost the entire length of the shroud case. The length of the resistance plate is horizontally disposed, and a slider is attached to each of the left and right outer sides of the wheel frame so as to be slidably engaged with one side portion of the opposing resistance plate. A seismic isolation device for an overhead crane having a configuration in which a viscous liquid having a required viscosity is filled in the shroud case is disclosed.

  Accordingly, the slider that can move integrally with the crane body can be slidably engaged with one side of the resistance plate, and the viscous resistance of the viscous liquid filled in the shroud case can be applied to the resistance plate. Therefore, it is possible to make it difficult to lift the crane body during an earthquake, and to reduce the impact when landing after lifting, thereby preventing the crane body from being dropped or damaged.

  Further, in Patent Document 2, in an overhead crane that runs on a running rail at the upper end of a runway girder arranged on a building frame, a vertical damping member having a damper and a slider containing a viscous fluid is fixed to the crane girder. An overhead crane is disclosed in which a slider support plate is provided in the traveling direction of the overhead crane at the end of the building housing that supports the runway girder, and the slider is disposed so as to be slidable with respect to the slider support plate. .

  Therefore, the vertical damping member having the damper and the slider containing the viscous fluid is fixed to the crane girder, and the slider is arranged so as to be slidable with respect to the slider support plate provided at the end of the building frame supporting the raw girder. Therefore, it is possible to reduce the vertical seismic response of the overhead crane and to improve the function of preventing the overhead crane from falling onto the floor surface.

JP-A-8-231183 JP 2001-253684 A

  The crane disclosed in Patent Document 1 is provided with a seismic isolation device between the crane body and the crane girder, and the crane disclosed in Patent Document 2 acts on the crane body using a viscous damper. It is intended to reduce the vertical seismic force. Therefore, neither of the cranes of Patent Documents 1 and 2 is essentially configured to prevent the crane body from being lifted.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an overhead crane that sufficiently prevents the crane body from lifting when an earthquake occurs and that does not cause damage to the crane girder. It is in.

  In order to achieve the above object, an overhead crane according to claim 1 includes a pair of crane girders disposed on a building frame, a pair of traveling rails installed at the upper ends of the pair of crane girders, and a pair of the travelings. An overhead crane having a crane main body traveling on a rail, the main body side magnet provided on the crane main body, and a girder side magnet provided on the crane girder, the crane main body and the crane girder And are configured to attract each other.

  By adopting such a configuration, the crane body and the crane girder are attracted to each other by a magnetic force, so that the crane body is kept pressed against the traveling rail by the magnetic force, and the crane body is prevented from being lifted. Thereby, for example, even when a large shake or vibration occurs during an earthquake or the like, it is possible to prevent the crane body from falling off or derailing and to avoid damaging the crane girder. Furthermore, since the crane body and the crane girder are attracted to each other by magnetic force, it is possible to suppress the horizontal swing of the crane body.

  The overhead crane according to claim 2 is the overhead crane according to claim 1, wherein the main body side magnet is at least one electromagnet provided at a bottom of the crane main body, and the girder side magnet is the crane girder. It is the magnetic pole row | line | column of the electromagnet arranged in the traveling direction of the said crane main body at a fixed pitch in the side part of this.

  By adopting such a configuration, the main body side magnet and the girder side magnet can be easily configured, and by adjusting the current flowing through those electromagnets, the crane main body is securely pressed against the traveling rail Is secured, and the crane body can be prevented from being lifted. Also, no matter where the crane body is on the traveling rail, the girder-side magnet is a magnetic pole array of electromagnets, so the girder-side electromagnet is just opposite to the body-side magnet or in the vicinity of the body-side magnet. Therefore, the main body side magnet and the girder side magnet can be attracted to each other and the crane main body can be prevented from being lifted without moving the crane main body during an earthquake or the like.

  The overhead crane according to claim 3 is a pair of crane girders arranged on a building frame, a pair of traveling rails installed on the upper ends of the pair of crane girders, and a crane body traveling on the pair of traveling rails, In the overhead crane, the crane main body side electromagnet provided in the crane main body, the electromagnet magnetic pole row provided in the crane girder, and an earthquake detecting earthquake vibration at a place where the crane main body is installed A detection unit; a crane body position detection unit that detects a position of the crane body on the traveling rail; a current supply unit that supplies a current to the electromagnet on the main body side and the electromagnet that forms the magnetic pole array; and the earthquake When the detection unit detects an earthquake, the crane position detection unit detects the position of the crane body and is located in the vicinity of the electromagnet on the body side. The earthquake detection unit, the crane position detection unit, and the current supply unit are specified such that the electromagnet of the magnetic pole row is specified, and the current supply unit supplies current to the main body side electromagnet and the specified electromagnet of the magnetic pole row. And a central control unit for controlling.

  By adopting such a configuration, when the central control unit receives a signal that the initial vibration of the earthquake has been detected from the earthquake detection unit, the central control unit obtains the current crane body position information from the crane body position detection unit, The electromagnets that constitute the girder-side magnetic pole array facing or near the electromagnet on the side are specified, and a current is supplied to the electromagnet on the main body side and the electromagnet of the specified magnetic pole array by the current supply unit. It can be controlled to attract each other. Therefore, immediately after detecting the initial vibration of the earthquake, the crane body is kept pressed against the traveling rail by the magnetic force, and the crane body is prevented from being lifted.

  The overhead crane according to claim 4 is the overhead crane according to claim 1, wherein the main body side magnet includes at least one set of N poles arranged in the traveling direction of the crane main body at the bottom of the crane main body and It is an S pole permanent magnet, and the girder side magnet is a magnetic pole array of electromagnets in which N poles and S poles are alternately arranged at a certain pitch in the traveling direction of the crane body on the side of the crane girder. It is characterized by that.

  By adopting such a configuration, at least one set of N-pole and S-pole permanent magnets provided at the bottom of the crane body and the girder-side electromagnet facing the at least one set of permanent magnets are attracted to each other. In this way, the crane body can be prevented from lifting during an earthquake with a simple configuration. Moreover, no matter where the crane body is on the traveling rail, the girder-side magnet is a magnetic pole row of electromagnets, so that the girder-side electromagnet is just opposite to at least one pair of N-pole and S-pole permanent magnets. Or in the vicinity of those permanent magnets, it is possible to prevent the crane body from lifting by pulling the body side magnet and the girder side magnet together without moving the crane body during an earthquake or the like. . Since at least one set of N-pole and S-pole permanent magnets is used for the main body side magnet, it is possible to increase the magnetic force attracted by the main body side magnet and the girder side magnet.

  The overhead crane according to claim 5 is the overhead crane according to claim 4, characterized in that the polarity of the magnetic pole array of the girder-side magnet can be changed spatially and temporally. Therefore, the crane main body can be moved by the principle of a linear motor, and the precise position adjustment of the crane main body is performed.

  According to the overhead crane of the present invention, the crane main body and the crane girder are configured to attract each other by magnetic force, so that the crane main body is prevented from lifting during an earthquake, and the crane main body is dropped or derailed, and the horizontal swing Can be prevented. Therefore, it is possible to prevent damage to the crane girder during an earthquake, and it is possible to safely protect the overhead crane.

  Embodiments of the present invention will be described in detail below with reference to the drawings.

(First embodiment)
FIG. 1 is an enlarged cross-sectional view of a main part according to the first embodiment of the overhead crane of the present invention. A pair of traveling rails 16 are installed on the upper ends 14 b of the pair of crane girders 14 arranged on the building frame 12, and the crane body 10 moves on the traveling rails 16. In addition, in FIG. 1, it has shown about the one side of the crane girder 14, Since the structure is the same about the other side, it is abbreviate | omitting.

  The crane body 10 is thin on both sides on the crane girder 14 side for attaching the wheels 18, and therefore constitutes a first bottom portion 10 a and a second bottom portion 10 b, and the first bottom portion 10 a and the second bottom portion. There is a step between 10b. Wheels 18 for traveling on the traveling rail 16 are provided at the four corners of the crane body 10 on the first bottom portion 10a. The main body side electromagnets 26 are provided at the four corners of the second bottom portion 10 b of the crane main body 10. A magnetic pole array 24 of an electromagnet, which is a girder-side magnet, facing the electromagnet 26, which is a main body-side magnet, at a predetermined interval, is arranged on the side 14a of the crane girder 14 at a constant pitch along the traveling direction of the crane main body 10. It is installed at. These states will be described in detail below with reference to FIG.

  FIG. 2 is an explanatory diagram showing the installation of the main body side magnet and the girder side magnet. The main body side electromagnets 26 are provided at the four corners of the second bottom portion 10b of the crane main body 10 as described above. The girder-side magnet is a magnetic pole array 24 composed of electromagnets arranged at a constant pitch, and the main body-side electromagnet 26 is configured to face the magnetic pole array 24 at a constant interval. Here, the width (lateral width) of the moving direction of the crane main body 10 of the electromagnets 26 and the magnetic pole rows 24 is the same, and the electromagnets constituting the magnetic pole row 24 are spaced apart by one and are separated from the crane main body 10. A plurality are arranged in the moving direction.

  When the electromagnet 26 on the main body side and one of the electromagnets constituting the magnetic pole row 24 are just facing each other, or facing each other with the center shifted, they attract each other when a current is passed through these electromagnets. The state of being pressed against the traveling rail 16 is ensured, and the crane body 10 does not rise even if it receives a large shake due to an earthquake.

  Here, depending on the position of the crane body 10, when the electromagnet 26 on the main body side and one of the electromagnets constituting the magnetic pole row 24 are shifted by exactly one, in other words, the electromagnet 26 is the electromagnet of the magnetic pole row 24. If it is located just in a place where there is no current, a current is passed through the electromagnet of the magnetic pole row 24 closest to the electromagnet 26 on the main body side. Then, the crane main body 10 moves to the front or rear in the movement direction of the crane main body 10 by moving the width of about one electromagnet, and the state where it is pressed against the traveling rail 16 is ensured. In addition, although the electromagnet 26 is provided in the four corners on the second bottom portion 10 b of the crane body 10, the positional relationship between the electromagnets 26 and the electromagnets constituting the magnetic pole row 24 is the same. That is, when one of the electromagnets of the main body side magnet is just opposite to the electromagnet of the magnetic pole row of the girder side magnet, the remaining three electromagnets are also in such a positional relationship.

  The distance between the electromagnet 26 and the magnetic pole row 24, the size of each electromagnet constituting the electromagnet 26 and the magnetic pole row 24, the strength of the magnetic force, etc. are the size, weight, overhead crane usage status, etc. It can be appropriately determined in consideration.

  FIG. 3 is a schematic configuration diagram for the operation of the overhead crane of the present invention. This configuration is an example, and the present invention is not limited to this configuration for moving the overhead crane of the present invention. For example, the operation mode determination unit 38, the display unit 42, and the like may be provided as necessary. In FIG. 3, in order to operate an overhead crane, the structure which has the earthquake detection part 32, the crane main body position detection part 34, the electromagnet control part 36, the operation mode discrimination | determination part 38, the central control part 40, and the display part 42 is shown. ing.

  The earthquake detection unit 32 immediately detects the vibration when the building in which the overhead crane is installed is vibrated or shaken by an earthquake. In particular, it is configured to detect sharply the initial vibration of an earthquake. The crane body position detection unit 34 detects the current position of the crane body 10 with respect to the crane girder 14 or the building frame. For example, the distance from one end of the crane girder 14 of the crane body 10 is accurately measured using a pulse motor, a laser length measuring device, a potentiometer, or the like. Then, as will be described later, the central control unit 40 identifies the electromagnets of the magnetic pole array 24 facing or near the electromagnet 26 on the main body side.

  The current supply unit 36 has a function of determining the strength and polarity of the current flowing through the electromagnet 26 on the main body side and the electromagnet of the above-described specified magnetic pole array. Normally, when current is applied, the polarities are determined so as to attract each other. However, if the electromagnet 26 on the main body side is the S pole, the electromagnet of the magnetic pole array is the N pole. In addition, the electric current to flow can be changed by individual electromagnets, and is configured so that all the electromagnets can have the same polarity or only the electromagnets in a specific place can have the same polarity.

  The operation mode discrimination unit 38 discriminates for what purpose the main body side magnet and the girder side magnet are currently used. Usually, three operations are set. That is, there are three modes: an emergency mode, a crane body stop mode, and a linear motor operation mode. For example, when the earthquake detection unit 32 detects vibration due to an earthquake or the like, the emergency mode is set. These modes are described later.

  When the earthquake detection unit 32 detects an earthquake, the central control unit 40 detects the position of the crane main body 10 by the crane position detection unit 34, and specifies the electromagnet of the magnetic pole row 24 located in the vicinity of the electromagnet 26 on the main body side. The earthquake detection unit 32, the crane position detection unit 34, and the current supply unit 36 are controlled so that the current supply unit 36 supplies a current to the electromagnet 26 on the main body side and the electromagnet of the specified magnetic pole array 24. In addition, the above three modes are managed. Specifically, the signal indicating that the initial vibration of the building has been detected from the earthquake detector 32 is received, and the crane body 10 from the crane body position detector 34 is received. Receiving the position detection signal, transmitting a display signal indicating the position of the crane body 10 to the display unit 42, and controlling the electromagnetic supply unit 36 to pass a current through the electromagnet 26 on the main body side and the magnetic pole array 24 of the electromagnet. And a command to change the magnetic poles of the magnetic pole row 24 are issued.

  The display unit 42 displays position information of the crane main body 10, the strength of the current flowing through the electromagnet 26 on the main body side and the magnetic pole row 24 of the electromagnet, the state of polarity of the magnetic pole row 24, the operation mode, and the like. Buttons for moving the crane main body 10 forward, backward, and stop, the moving speed of the crane main body 10 and the like are also displayed in the linear motor operation mode described later.

  Hereinafter, the case where the earthquake detection unit 32 detects the vibration of the building due to the earthquake will be described. The purpose is to make the crane body 10 quickly pressed against the traveling rail 16 at the time of an earthquake and to prevent the crane body 10 from being lifted by the earthquake. This is called an emergency mode. When the central control unit 40 receives a signal indicating that the shaking of the building has been detected from the earthquake detection unit 32, the central control unit 40 obtains information on the current position of the crane main body 10 from the crane main body detection unit 34. Next, an electromagnet constituting the magnetic pole row 24 facing the electromagnet 26 provided at the bottom of the crane body 10 is specified. Here, the position of the crane main body 10 is detected by measuring the distance from one end of the crane girder 14 with a laser length measuring device (not shown), and the electromagnet 26 attached to the bottom of the crane main body 10. The electromagnet of the magnetic pole array 24 of the girder-side magnet that is opposed to the above is determined. After determining the electromagnets of the opposing magnetic pole row 24, a current is passed from the current supply unit 36 to the electromagnet 26 and the electromagnet 26, which is the main body side magnet, so that the electromagnet on the main body side and the electromagnet of the magnetic pole row 24 are attracted to each other. The main body 10 is pressed against the traveling rail 16. The current that flows in the emergency mode is set to be larger than that in a normal crane body stop mode that will be described later, and the crane body 10 ensures a state in which the crane body 10 is reliably pressed against the traveling rail 16 by a strong magnetic force. .

  Since the state where the crane body 10 is pressed against the traveling rail 16 as described above is secured against the initial shaking of the earthquake, the horizontal shaking as well as the crane body 10 is reliably suppressed. . Therefore, even if a large up-and-down swing occurs after the initial swing, the crane body 10 is reliably prevented from floating from the traveling rail 16, and as a result, the crane girder 14 and the like are not damaged at all.

  After restarting the overhead crane after confirming that there is no particular problem after the earthquake, return to the normal crane body fixing mode to cancel the emergency mode. All of this work can be performed on the display unit 42.

  In a normal case where no earthquake or the like occurs, the crane body 10 moves on the traveling rail 16 by a motor or the like (not shown). When the crane main body 10 is moved, no current flows through the electromagnets constituting the main body side magnet and the girder side magnet, and therefore the main body side magnet and the girder side magnet are not attracted to each other. When the crane body 10 is moved to a desired location, an electric current is applied to the electromagnets constituting the main body side magnet and the girder side magnet so that the main body side magnet and the girder side magnet are attracted to each other and the crane main body 10 is pressed against the traveling rail 16. Secure the state. This is referred to as a crane body fixing mode.

(Second Embodiment)
FIG. 2 is an explanatory view showing a state of installation of a main body side magnet and a girder side magnet according to the second embodiment of the overhead crane of the present invention. The main body side magnet is composed of a set of N-pole and S-pole permanent magnets 22. The permanent magnets 22 are provided at the four corners of the second bottom portion 10 b of the crane body 10. Here, the N-pole and S-pole permanent magnets 22 are arranged side by side in the traveling direction of the crane body 10.

  The girder-side magnet is an electromagnet magnetic pole array 20 in which a plurality of electromagnets are arranged without gaps in the traveling direction of the main body crane 10, and the above-described permanent magnet 22 is opposed to the magnetic pole array 20 with a certain interval. It is configured. The lateral width of each electromagnet constituting the magnetic pole array 20 in the traveling direction of the crane body 10 and the lateral width of the S pole and N pole permanent magnets in the traveling direction of the crane body 10 are the same. The distance between the permanent magnet 22 and the magnetic pole row 20, the size of the permanent magnet 22, the strength of the magnetic force of the permanent magnet 22 and the electromagnet, etc., take into account the size, weight, crane usage status, etc. And can be determined as appropriate.

  In such a configuration, when the earthquake detection unit 32 detects the vibration of the building due to the earthquake, the crane main body 10 can be quickly pressed against the traveling rail 16 to prevent the crane main body 10 from being lifted by the earthquake. is there. Specifically, when the central control unit 40 receives a signal indicating that the shaking of the building has been detected from the earthquake detection unit 32, the central control unit 40 obtains information on the current position of the crane main body 10 from the crane main body detection unit 34. Next, the electromagnets constituting the magnetic pole array 20 facing the pair of N-pole and S-pole permanent magnets 22 provided at the bottom of the crane body 10 are specified. Here, the position detection of the crane body 10 is performed by accurately measuring the distance from one end of the crane girder 14 with a laser length measuring device (not shown) as in the first embodiment. The electromagnet of the magnetic pole array 20 of the girder-side magnet facing the set of N-pole and S-pole permanent magnets 22 attached to the bottom of 10 was determined. After determining the electromagnets of the opposing magnetic pole rows 20, current is passed through the electromagnets so that the pair of N- and S-pole permanent magnets 22 and the girder-side magnets are attracted to each other, and the crane body 10 travels. The state is pressed against the rail 16.

  As described above, since the crane body 10 is pressed against the traveling rail 16 by the magnetic force of the main body side magnet and the girder side magnet as described above, the crane main body 10 is not lifted up. Horizontal shaking is also reliably suppressed. Therefore, even if a large up-and-down swing occurs after the initial swing, the crane body 10 is reliably prevented from floating from the traveling rail 16, and as a result, the crane girder 14 and the like are not damaged at all. In the case of the second embodiment, since the main body side magnet is composed of a pair of N-pole and S-pole permanent magnets 22, it is possible to make the entire apparatus compact, and the main body side. It is possible to increase the magnetic force between the magnet and the girder side magnet.

  In the second embodiment, the crane body 10 can be moved using the main body side magnet and the girder side magnet using the principle of the linear motor. This is called a linear motor operation mode. The permanent magnets 22 fixed to the four corners of the second bottom portion 10b of the crane body 10 are a set of magnets each composed of an N pole and an S pole. This set of magnets is arranged side by side in the moving direction of the crane body 10 as described above. In the crane body fixing mode, the electromagnet opposed to the permanent magnet 22 is an S-pole electromagnet for the N-pole permanent magnet and an N-pole electromagnet for the S-pole permanent magnet. It is controlled by the control unit 36.

  When the crane body 10 is moved, the polarity of the electromagnets facing the pair of permanent magnets 22 is made the same as that of the permanent magnets 22, and at the same time, the polarity of the adjacent electromagnets on the moving direction side is changed from the previous polarity. Then, since the crane body 10 is attracted to the electromagnet whose polarity has been changed, the crane body 10 moves slightly, that is, by one electromagnet. Therefore, the crane main body 10 can be moved by changing the polarity of the magnetic pole array 20 of the electromagnet one after another in time and space as the crane main body 10 moves. The moving speed of the crane body 10 depends on the strength of the current flowing through the electromagnet and the speed at which the polarity of the electromagnet is changed over time. It is possible to determine.

  And after moving the crane main body 10 to a desired place, electric current is applied to the electromagnets so that the electromagnets of the magnetic pole array 20 that is the girder side magnet facing the permanent magnets 22 that are the main body side magnets are attracted to each other. By making it flow, the crane body 10 can be stopped and placed. This state is the same as the above-described crane body fixing mode. In this state, the crane body 10 is reliably pressed against the traveling rail 16 by the magnetic force, so that the crane work can be performed safely.

  The display unit 42 displays the position of the crane body 10, the operation mode, the polarity of the magnetic pole array 20 of the electromagnet, and the like, and the crane body 10 can be moved on the screen during the linear motor operation. Since the movement of the crane body 10 is controlled by the minimum unit of movement, that is, for each electromagnet, the crane body 10 can be precisely positioned.

  As described above, in the crane according to the present invention, the crane body 10 and the crane girder 14 attract each other by magnetic force, so that the crane body 10 can be prevented from being lifted during an earthquake, and the crane body 10 can be dropped or derailed. In addition to preventing the damage, the crane girder 14 can be prevented from being damaged. Furthermore, since the crane main body 10 and the crane girder 14 attract each other by magnetic force, it is also possible to suppress the horizontal swing of the crane main body 10.

  Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the main body side magnet is attached to the second bottom portion of the crane main body 10 and the girder side magnet is attached to the side portion 14a of the crane girder 14, but the main body side magnet is attached to the first bottom portion of the crane main body 10 and the girder side magnet is attached to the crane girder. You may attach to the 10 upper end part 14b.

It is an important section expanded sectional view concerning a 1st embodiment of an overhead crane of the present invention. It is explanatory drawing which shows the mode of installation of the main body side magnet and girder side magnet of FIG. It is a schematic block diagram for operation | movement of the overhead crane of this invention. It is a principal part expansion perspective view which concerns on 2nd Embodiment of the overhead crane of this invention. The conventional overhead crane is shown, Comprising: The figure (a) is a schematic plan view, The figure (b) is a schematic plan view. It is an expanded sectional view of the part shown by arrow B of Drawing 4 (b), and the figure (a) is an expanded sectional view and the part (b) is an expanded sectional view of a crane girder.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Crane main body 12 Building frame 14 Crane girder 16 Travel rail 18 Wheels 20 and 24 Magnetic pole row 22 One set of S pole and N pole permanent magnet 26 Electromagnet 32 on the main body side Earthquake detection part 34 Crane main body position detection part 36 Current supply part 38 Operation Mode Discriminating Unit 40 Central Control Unit 42 Display Unit

Claims (5)

In an overhead crane having a pair of crane girders arranged on a building frame, a pair of traveling rails installed on the upper ends of the pair of crane girders, and a crane body traveling on the pair of traveling rails,
A main body side magnet provided in the crane main body,
A girder-side magnet provided on the crane girder,
The overhead crane, wherein the crane body and the crane girder are attracted to each other. The main body side magnet is at least one electromagnet provided at the bottom of the crane main body,
2. The overhead crane according to claim 1, wherein the girder-side magnet is a magnetic pole array of electromagnets arranged at a constant pitch in a traveling direction of the crane body on a side of the crane girder. In an overhead crane having a pair of crane girders arranged on a building frame, a pair of traveling rails installed on the upper ends of the pair of crane girders, and a crane body traveling on the pair of traveling rails,
An electromagnet on the crane body side provided in the crane body;
A magnetic pole array of electromagnets provided in the crane girder;
An earthquake detection unit for detecting earthquake vibration at a place where the crane body is installed;
A crane body position detector for detecting the position of the crane body on the traveling rail;
A current supply unit for supplying current to the electromagnet on the main body side and the electromagnet constituting the magnetic pole row;
When the earthquake detection unit detects an earthquake, the crane position detection unit detects the position of the crane main body, identifies an electromagnet of the magnetic pole row located in the vicinity of the electromagnet on the main body side, and the current supply unit A central control unit that controls the earthquake detection unit, the crane position detection unit, and the current supply unit so as to supply current to the main body side electromagnet and the electromagnet of the specified magnetic pole row,
An overhead crane characterized by comprising: The main body side magnet is at least one set of N pole and S pole permanent magnets arranged in the traveling direction of the crane main body at the bottom of the crane main body,
2. The girder-side magnet is an electromagnet magnetic pole array in which N poles and S poles are alternately arranged at a constant pitch in a traveling direction of the crane body on a side of the crane girder. The overhead crane as described in.   The overhead crane according to claim 4, wherein the polarity of the magnetic pole array of the girder-side magnet can be changed spatially and temporally.

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