3697results about "Permanent magnets" patented technology

A magnetic latch for a display of a laptop computer is disclosed. The latch uses magnetic attraction to maintain the display closed and uses magnetic repelling forces to pop-up the display when opened. The latch includes one or more magnetic elements in the body of the laptop and at least one magnetic element in the display. When the display is closed, the magnet element in the display is positioned adjacent the magnet element in the body having an opposite polarity so that the magnet elements are attracted to one another. To pop-up the display, the user moves the magnetic element in the display so that it meets the magnetic pole in the body having the same polarity. When these meet, the repelling force between them causes the display to open slightly so that a user can then readily open the display.

With a view toward implementing a thermal controlling method for making reversible a temperature characteristic of a magnetic field generator using permanent magnets small in Hcj, a magnetic field generator whose temperature characteristic is reversible, using permanent magnets small in Hcj, and an MRI apparatus provided with such a magnetic field generator, there is provided a method for controlling the temperature of a magnetic field generator having a pair of disc-shaped permanent magnets whose magnetic poles opposite in polarity to each other are opposed to each other with spacing defined therebetween, and a yoke that forms return passes for magnetic fluxes of the permanent magnets, comprising the steps of raising the temperature from room temperature to a temperature higher than the room temperature, maintaining the temperature higher than the room temperature, and lowering the temperature from the temperature higher than the room temperature to the room temperature, whereby the temperature characteristics of the permanent magnets are made reversible.

A magnet assembly comprising a magnet mounted for pivoting about a first axis spaced from the magnet, and rotating about a second axis that is perpendicular to and intersects with the first axis. The magnet comprising a plurality of segments each with a magnetization direction such that through a combination of pivoting and rotating the magnet projects a magnetic field in any direction at an operating point spaced from the front of the assembly. The segmented construction with segments of different magnetization directions allows small changes in the orientation of the magnet to substantially change the magnet field direction at a system operating point.

The invention disclosed is a method of levitating one or both ends of an object permanently or temporarily, or altering the distance between two objects or the momentum of an object by manipulating the direction of the magnetic field of a permanent or electromagnet.

A magnetic attachment mechanism and method is described. The magnetic attachment mechanism can be used to releasably attach at least two objects together in a preferred configuration without fasteners and without external intervention. The magnetic attachment mechanism can be used to releasably attach an accessory device to an electronic device. The accessory device can be used to augment the functionality of usefulness of the electronic device.

An electromagnet comprises a pair of magnetic pole 1a and 1b, a return yoke 3, exciting coils 4 and 5, etc. In an interior portion of a magnetic pole, plural spacers 2a-2g are provided putting side by side in a horizontal direction. Each of the spaces 2a-2g is an air layer and a longitudinal cross-section is a substantially rectangular shape and the space has a lengthily extending slit shape in a vertical direction against a paper face in FIG. 1. The plural spaces are mainly arranged toward a right side from a beam orbit center O and an interval formed between adjacent spaces is narrower toward the right side. The electromagnet having a simple magnetic pole structure and a wide effective magnetic field area in a case where a maximum magnetic field strength is increased can be secured.

By a force generation device which can generate a magnetic attraction and gas static pressure between a detection system provided on a lower surface side of an FIA surface plate and a surface plate, a predetermined clearance is formed between the detection system and the surface plate, and in a state where the clearance is formed (a floating state), the detection system is driven by a drive device in at least an uniaxial direction within a horizontal plane. Therefore, because the detection system is in a non-contact state to the base platform, movement (positioning) of the detection system with high precision becomes possible. Further, by setting an attraction larger than a repulsion generated by the force generation device, the detection system can be fixed (landed) in a state positioned with high precision.

Magnetic circuit that has (a) a source of magnetic flux which includes an electromagnet or one or more permanent magnets, (b) at least two oppositely polarisable pole extension bodies associated with the magnetic flux source, the bodies being disc, wheel, roller or similarly shaped with an outer circumferential surface and held rotatable about respective axes of rotation, and (c) a ferromagnetic counter body which is arranged to cooperate with the pole extension bodies such as to provide an external flux path for the magnetic flux when in magnetic proximity or contact with the circumferential surface of the pole extension bodies, which is characterised in that the magnetic flux source is held stationary relative to the rotatable pole extension bodies.

A permanent magnet in which the magnetization direction varies with location to optimize or restrict a magnetic field property in a selected direction at a selected point. The magnetic field property may be, for example, the transverse magnetic field, axial magnetic field, axial gradient of the transverse magnetic field, transverse gradient of the transverse magnetic field, axis gradient of the axial magnetic field, transverse gradient of the axial magnetic field, the product of the transverse magnetic field and the transverse gradient of the transverse magnetic field, the product of the transverse magnetic field and the axial gradient of the transverse magnetic field, the product of the axial magnetic field and the transverse gradient of the axial magnetic field, or the product of the axial magnetic field and the axial gradient of the axial magnetic field. The magnet may be formed of one or more segments in which the magnetization direction varies smoothly and continuously, or the magnet may be formed of a plurality of segments in which the magnetization direction is constant. A method of making and using such magnets is also disclosed.

A magnetic levitation sliding structure is provided. The sliding structure includes a first slider member including a guide portion with a first magnet, a second slider member including a receiving portion with a channel-shaped second magnet, the receiving portion being configured to receive the guide portion so as to slide on the first slider member. The first and second magnets are configured so that a repelling force can act there between for facilitating the sliding operation. In some embodiments the sliding structure includes at least one attraction member configured at an initial and/or final position of one of the first and second slider members. A portable electronic device including the magnetic levitation sliding structure is also provided.

A sensing system senses whether or not a lock's bolt (140), e.g. deadbolt, is aligned with a hole (150) which the bolt is to engage in the locked state. In electronic locks, the bolt is not driven into the hole until the sensing system indicates that the bolt is aligned with the hole. Another sensing system senses the position of the bolt and/or a dead-latch bar (1310). This sensing system is spaced from the bolt's end engaging the hole in order not to interfere with the alignment sensing. The two sensing systems are used to determine whether the lock is locked or unlocked. A magnet system provides alignment assistance to align the bolt with the hole before the bolt is driven into the hole. Position encoding for lock and non-lock devices, and other features and embodiments are also provided.

A tablet case with a cover, the tablet case comprising a housing having three upstanding walls, at least one of the three upstanding walls having a flange, the housing being adapted to receive and retain a tablet. The tablet case further comprises a cover having a substantially rectangular foldable planar member and an elongated member which extends from the cover into an indentation on the inside of the housing. A section of the elongated member is secured to the indentation to form a substantially planar surface arranged to abut the rear wall of a tablet. First and second magnetic means are provided on the housing and cover respectively to allow the cover to be folded into a stand and secured to the housing or to allow the cover to simply shield a tablet screen.