WO1996007610A1 - Appareil de levage - Google Patents

Appareil de levage Download PDF

Info

Publication number
WO1996007610A1
WO1996007610A1 PCT/GB1995/002088 GB9502088W WO9607610A1 WO 1996007610 A1 WO1996007610 A1 WO 1996007610A1 GB 9502088 W GB9502088 W GB 9502088W WO 9607610 A1 WO9607610 A1 WO 9607610A1
Authority
WO
WIPO (PCT)
Prior art keywords
lifting apparatus
upper unit
permanent magnets
lifting
load
Prior art date
Application number
PCT/GB1995/002088
Other languages
English (en)
Inventor
Amitava Basak
Nabeel Shirazee
Original Assignee
University College Cardiff Consultants Limited
Orb Electrical Steel Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University College Cardiff Consultants Limited, Orb Electrical Steel Limited filed Critical University College Cardiff Consultants Limited
Priority to EP95930632A priority Critical patent/EP0777624B1/fr
Priority to DE69507815T priority patent/DE69507815D1/de
Publication of WO1996007610A1 publication Critical patent/WO1996007610A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • H01F7/04—Means for releasing the attractive force
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C1/00—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles
    • B66C1/04—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles by magnetic means
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/02—Permanent magnets [PM]
    • H01F7/0231—Magnetic circuits with PM for power or force generation
    • H01F7/0252—PM holding devices
    • H01F7/0257—Lifting, pick-up magnetic objects

Definitions

  • This invention relates to a lifting apparatus and, in particular, to a magnetic lifting apparatus for heavy loads.
  • Conventional lifting apparatus often employ electromagnetic means for lifting heavy loads.
  • an electric current is passed through a large coil of a lifting head to produce a magnetic force, in accordance with known principles.
  • This magnetic force attracts the load and the lifting head together in order that the load may be lifted and moved as required.
  • the current to the lifting head coil is cut off such that the magnetic force is removed and the load becomes detached from the lifting head.
  • a lifting apparatus which comprises an upper unit comprising a plurality of spaced-apart permanent magnets having pole pieces disposed between them, a lower unit comprising a plurality of poles arranged to be positioned at the ends of the pole pieces between the permanent magnets to form a magnetic circuit, and means for displacing the lower unit away from the upper unit in order to break said magnetic circuit.
  • the upper unit comprises a plurality of generally C-shaped assemblies of permanent magnets nested together, such that the ends of the permanent magnet assemblies are positioned at intervals along the lower or lifting surface of the upper unit of the apparatus.
  • a section of non-magnetically permeable material is positioned below the ends of the permanent magne assemblies.
  • each end o the upper unit for diverting end flux to the load bein lifted.
  • each such arrangement comprises an en plate of magnetically permeable material and a series o permanent magnets positioned between that end plate and th corresponding end of the upper unit.
  • the lower uni has opposite end pieces corresponding to the respective en plates of the upper unit.
  • the pole pieces of the upper unit are mad of a magnetically permeable material, such as 2.5% silico iron.
  • the poles of the lower unit may be made of cobalt iro alloy, and may have sloping edges or may be adapted for liftin circular objects, such as tubes.
  • the means for displacing the lower unit awa from the upper unit comprises hydraulic rams which ca preferably re-attach the lower and upper units as required
  • the hydraulic rams are preferably operable by means of oi pumped into or out of them.
  • the oil may be pumped by a han pump or electrical pumps.
  • the system further includes means fo performing computer controlled measurements of certai parameters in order to give advanced warnings of unsaf loading, for example tilt in the load being lifted, temperatur limitations and exceeding the weight safety factor limit.
  • the permanent magnets are rare-eart permanent magnets. These may all comprise Neodymium-Boron-Iro (NdFeB) , or they may comprise Neodymium-Boron-Iron (NdFeB except for some sections of Samarium Cobalt (SmCo) .
  • NdFeB Neodymium-Boron-Iro
  • SmCo Samarium Cobalt
  • a lifting apparatus having a 100% fail safe liftin capability for loads up to 1 tonne or more and with a maximu operational temperature of 300°C. It is further possible t provide a lighter and more compact lifting apparatus than prio art systems, with negligible power consumption due to it efficient design.
  • FIGURE 1 is a schematic cross-sectional view of a first embodiment of lifting apparatus in accordance with the present invention
  • FIGURE 2 is a graphical representation to show an overview of the energy densities and coercivites of ferrite and rare-earth permanent magnet materials
  • FIGURE 3 is a view corresponding to Figure 1, showing the lifting apparatus when the release mechanism is in operation;
  • FIGURE 4 is a section, on a plane perpendicular to Figure 3, through an end portion of the apparatus.
  • FIGURE 5 is a schematic cross-sectional view of a second embodiment of the present invention.
  • a lifting apparatus which comprises a 'Multi-C-Pole Unit' 1 (MCPU) and a 'Lower Assembly Unit' 2 (LAU) having a load 3 attracted thereto.
  • the MCPU 1 comprises a plurality of generally C- shaped magnet assemblies 4, each assembly 4 comprising a plurality of flat magnets disposed edge-to-edge with each other, with each such magnet elongated lengthwise of the apparatus (i.e. perpendicular to the plane of the paper on which Figure 1 is drawn) .
  • the end magnets 5 of the assemblies 4 are positioned at equally spaced intervals along the lower or lifting surface of the MCPU 1. Positioned between each of the C-shaped magnet assemblies 4, are a plurality of generally C-shaped magnetic pole pieces 6, made for example of 2.5% Silicon Iron: it will be noted that the end magnets 5 of the assemblies 4 project downwardly beyond the lower ends of the pole pieces 6.
  • the LAU 2 comprises a plurality of poles 7, made for example of cobalt iron alloy, and sections of non- magnetically permeable material 8, arranged such that the poles 7 are positioned between the projecting ends 5 of the C-shaped magnet assemblies 4, and the sections of non-magnetically permeable material 8 are positioned directly below the projecting ends 5 of the respective C-shaped magnet assemblies 4.
  • the lifting apparatus further comprises two hydraulic rams 9 positioned on either side, with their opposite ends mounted to the MCPU 1 and the LAU 2 respectively by means o non-magnetically permeable brackets 9a.
  • the hydraulic rams are operated by means of oil which is pumped into them from small oil reservoir 10 at the top of the MCPU 1.
  • the apparatu comprising the MCPU 1 and the LAU 2 is covered by a layer o non-magnetically permeable material.
  • the MCPU 1 is suspende by steel ropes (not shown) via load cells 11.
  • the load cell 11 may have means which are computer controlled for measurin certain parameters in order to give advanced warnings of unsaf loading, for example, tilt in the load 3 being lifted temperature limitations and exceeding the weight safety facto limit.
  • Figure 4 shows an arrangement which is provided at eac end of the apparatus, for diverting the end flux to the loa 3 being lifted.
  • This arrangement comprises permanent magnet 15 positioned across the ends of the vertical limbs o respective adjacent pairs of the magnets of the C-shape assemblies 4 of the MCPU 1 (the magnets 15 being elongated i the direction perpendicular to the plane of the paper on whic Figure 4 is drawn) .
  • magnets 15a are positioned agains the ends of alternate pole pieces 6, at the upper region thereof: it will be noted that like poles of the magnet 15,15a face outwardly.
  • An end plate 16 of magneticall permeable material is positioned across the outer faces of th magnets 15,15a, and the LAU 2 has a corresponding end-piece 17
  • the MCPU 1 has an outer casing 18 which extends over its top sides and ends as shown, and typically may comprise hig strength bronze or aluminium.
  • the end-piece 1 is mounted to the remainder of the unit by means of a membe 19, also typically of high strength bronze or aluminium.
  • a ferrite permanent magnet such as Ba0.6Fe 2 0 3 21 has a very low magnetic strength (i.e. a (B d tt d ) max of 34.4 kJ/m 3 and a Hcj of 190 kA/m) compared with the magnetic strength of rare-earth permanent magnets such as samarium cobalt (SmCo) 22,24 and neodymium iron boron (NdFeB) 23.
  • rare-earth permanent magnets such as samarium cobalt (SmCo) 22,24 and neodymium iron boron (NdFeB) 23.
  • SmCo samarium cobalt
  • NdFeB neodymium iron boron
  • ferrite permanent magnets are substantially cheaper than rare-earth permanent magnets, it is preferable to use rare-earth permanent magnets for lifting purposes because a smaller, more compact and lighter lifting apparatus can be constructed due to the high magnetic strength of such magnet
  • the individual magnets 12 of the C-shaped permanent magnet assemblies 4 are preferably Neodymium-Iron-Boron (NdFeB) permanent magnets.
  • the end magnets 5 are preferably Samarium Cobalt (SmCo) permanent magnets for a maximum operating temperature of 300°C. However, they may alternatively be NdFeB permanent magnets if the operating temperature will not exceed 120°C. This would make the apparatus less expensive to manufacture because NdFeB permanent magnets are less expensive than those made of SmCo.
  • SmCo Samarium Cobalt
  • the apparatus is designed such that the flux level at the lifting pole face 13 is maximised such that the poles 7 can attract a rough surface (up to 4mm ridges) with ease and the system is able to lift a load 3 of 2 tonnes at an airgap 14 of 3-4mm.
  • the pumping of oil to and from the rams 9 may b carried out by a simple hand pump or by electrical pumps.
  • the shape of the pole surface can be varied in order t take into account the roughness of the surface of the load t be lifted (and, therefore, the resulting air-gap between th load and the pole face) .
  • a similar apparatus t that of Figure 1 is shown in Figure 5.
  • the roughness of the surface of the load 43 has resulted in much larger air-gap 54 between the load 43 and the pole fac 47.
  • the poles may also be shaped to lift circular objects such as pipes.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Power Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Load-Engaging Elements For Cranes (AREA)

Abstract

Appareil de levage composé d'un ensemble supérieur (1) comprenant une pluralité d'aimants permanents éloignés les uns des autres (5) entre lesquels se trouvent des pièces polaires (6), d'un ensemble inférieur (2) comprenant une pluralité de pôles (7) conçus pour être placés aux extrémités des pièces polaires (6) entre les aimants permanents (5) de l'ensemble supérieur, de façon à constituer un circuit magnétique permettant de soulever une charge (3), ainsi que de moyens (9) servant à éloigner l'ensemble inférieur (2) de l'ensemble supérieur (1), de manière à couper le circuit magnétique, afin de libérer la charge (3).
PCT/GB1995/002088 1994-09-02 1995-09-04 Appareil de levage WO1996007610A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP95930632A EP0777624B1 (fr) 1994-09-02 1995-09-04 Appareil de levage
DE69507815T DE69507815D1 (de) 1994-09-02 1995-09-04 Hebevorrichtung

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9417648A GB9417648D0 (en) 1994-09-02 1994-09-02 Lifting apparatus
GB9417648.4 1994-09-02

Publications (1)

Publication Number Publication Date
WO1996007610A1 true WO1996007610A1 (fr) 1996-03-14

Family

ID=10760720

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1995/002088 WO1996007610A1 (fr) 1994-09-02 1995-09-04 Appareil de levage

Country Status (4)

Country Link
EP (1) EP0777624B1 (fr)
DE (1) DE69507815D1 (fr)
GB (1) GB9417648D0 (fr)
WO (1) WO1996007610A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113039619A (zh) * 2018-10-24 2021-06-25 磁转换技术全球私人有限公司 线性地致动的磁性耦接装置
US11235873B2 (en) * 2018-03-22 2022-02-01 King Abdullah University Of Science And Technology Impulsive release mechanism and method
US11772214B2 (en) 2018-01-29 2023-10-03 Magswitch Technology, Inc. Magnetic coupling device
US11839954B2 (en) 2017-04-27 2023-12-12 Magswitch Technology, Inc. Magnetic coupling device with at least one of a sensor arrangement and a degauss capability
US11901141B2 (en) 2017-04-27 2024-02-13 Magswitch Technology, Inc. Variable field magnetic couplers and methods for engaging a ferromagnetic workpiece
US12023770B2 (en) 2019-04-12 2024-07-02 Magswitch Technology, Inc. Magnetic coupling device with at least one of a sensor arrangement and a degauss capability

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL71981C (fr) * 1900-01-01
US3009727A (en) * 1957-11-27 1961-11-21 Thew Shovel Co Permanent magnet lifting device
GB954370A (en) * 1960-02-12 1964-04-08 O S Walker Co Inc Permanent magnet lifting device
FR1407882A (fr) * 1964-06-24 1965-08-06 Braillon & Cie Sa Perfectionnement aux appareils de levage à aimants permanents
US3355209A (en) * 1965-05-10 1967-11-28 Magnetic Devices Inc Material handling device
FR2170967A1 (fr) * 1972-02-10 1973-09-21 Cefilac
DE2802537A1 (de) * 1978-01-20 1979-07-26 Hennig Gerhard Haftmagnetanordnung

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL71981C (fr) * 1900-01-01
US3009727A (en) * 1957-11-27 1961-11-21 Thew Shovel Co Permanent magnet lifting device
GB954370A (en) * 1960-02-12 1964-04-08 O S Walker Co Inc Permanent magnet lifting device
FR1407882A (fr) * 1964-06-24 1965-08-06 Braillon & Cie Sa Perfectionnement aux appareils de levage à aimants permanents
US3355209A (en) * 1965-05-10 1967-11-28 Magnetic Devices Inc Material handling device
FR2170967A1 (fr) * 1972-02-10 1973-09-21 Cefilac
DE2802537A1 (de) * 1978-01-20 1979-07-26 Hennig Gerhard Haftmagnetanordnung

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11901142B2 (en) 2017-04-27 2024-02-13 Magswitch Technology, Inc. Variable field magnetic couplers and methods for engaging a ferromagnetic workpiece
US11839954B2 (en) 2017-04-27 2023-12-12 Magswitch Technology, Inc. Magnetic coupling device with at least one of a sensor arrangement and a degauss capability
US11850708B2 (en) 2017-04-27 2023-12-26 Magswitch Technology, Inc. Magnetic coupling device with at least one of a sensor arrangement and a degauss capability
US11901141B2 (en) 2017-04-27 2024-02-13 Magswitch Technology, Inc. Variable field magnetic couplers and methods for engaging a ferromagnetic workpiece
US11772214B2 (en) 2018-01-29 2023-10-03 Magswitch Technology, Inc. Magnetic coupling device
US11780039B2 (en) 2018-01-29 2023-10-10 Magswitch Technology, Inc. Magnetic lifting device having pole shoes with spaced apart projections
US11931846B2 (en) 2018-01-29 2024-03-19 Magswitch Technology, Inc. Magnetic coupling device
US12017317B2 (en) 2018-01-29 2024-06-25 Magswitch Technology, Inc. Magnetic coupling device
US11235873B2 (en) * 2018-03-22 2022-02-01 King Abdullah University Of Science And Technology Impulsive release mechanism and method
EP3857575A4 (fr) * 2018-10-24 2022-07-13 Magswitch Technology Worldwide Pty Ltd. Dispositif de couplage magnétique à actionnement linéaire
CN113039619B (zh) * 2018-10-24 2023-12-12 磁转换技术有限公司 线性地致动的磁性耦接装置
CN113039619A (zh) * 2018-10-24 2021-06-25 磁转换技术全球私人有限公司 线性地致动的磁性耦接装置
US12023770B2 (en) 2019-04-12 2024-07-02 Magswitch Technology, Inc. Magnetic coupling device with at least one of a sensor arrangement and a degauss capability

Also Published As

Publication number Publication date
EP0777624B1 (fr) 1999-02-10
DE69507815D1 (de) 1999-03-25
GB9417648D0 (en) 1994-10-19
EP0777624A1 (fr) 1997-06-11

Similar Documents

Publication Publication Date Title
US4965695A (en) Permanent magnetic retaining device to move, affix or carry ferromagnetic parts or loads with electronic switching of the magnetic flux to release the carried load
CN101891105B (zh) 吸吊多层钢板的电永磁吊具
CA2037267C (fr) Trains sustentation magnetique a supraconductivite, reseau de transport correspondant, methode de commande et aimant supraconducteur mis en oeuvre
EP0777624B1 (fr) Appareil de levage
CN202279617U (zh) 电永磁钢板起重吊具
CN101544337A (zh) 电控永磁吸盘
JP2015536886A (ja) 永電磁石を備えるリフタ
EP3835110A1 (fr) Dispositif de transport a rail suspendu et système de rail de suspension hybride magnétique-électrique associé
CN111877590A (zh) 一种基于直流和交流电磁铁控制的摩擦摆减隔震装置
CN210574143U (zh) 一种配电变压器的防盗报警器
GB2292838A (en) Magnetic lifting apparatus
CN203095379U (zh) 环保电永磁起重电磁铁
CN201809024U (zh) 吸吊多层钢板的电永磁吊具
KR100406432B1 (ko) 영구자석을 이용한 코일 권상기
CN201567143U (zh) 宽厚板起重电磁铁
KR101691497B1 (ko) 튜브형 부재를 이동시키기 위한 전자석
Shirazee et al. Rare-earth permanent magnet lifting system for heavy loads
CN107434207B (zh) 一种自动卸料的电控永磁吸盘
EP4084284A1 (fr) Système d'économie d'énergie pour une installation électrique
CN213595697U (zh) 一种材料在线锁定吊具
CN109914289A (zh) 一种磁力路锥
CN201024036Y (zh) 钢板材起重电磁铁
CN101066738B (zh) 吊运不平板材起重电磁铁
CN203699639U (zh) 一种专业吸吊钢带卷的电永磁起重器
CN217973853U (zh) 一种永磁悬浮轨道单元

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA CN JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1995930632

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 1995930632

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: CA

WWG Wipo information: grant in national office

Ref document number: 1995930632

Country of ref document: EP