Magnet, attaching device, attaching arrangement and method for attaching to an object

Abstract

The invention relates to a magnet, which comprises a first permanent magnet for creating a magnetic field, and a shell and a centre, which are arranged to guide a magnetic flux to an object to be gripped. The magnet further comprises a slide, which is arranged to be movable in relation to the shell and the centre, which slide comprises said first permanent magnet, and an electric magnet for moving the slide. The invention also relates to an attaching device, and attaching arrangement and a method for attaching to an object.

1 - 21 . (canceled) 
     
     
         22 . A magnet, which comprises:
 a first permanent magnet for creating a magnetic field,   a shell and a centre, which are arranged to guide a magnetic flux to an object to be gripped,   a slide, which is arranged to be movable in relation to the shell and the centre, which slide comprises said first permanent magnet, and   an electric magnet for moving the slide, a coil of the electric magnet being arranged at least partly around the centre and attached to the shell.   
     
     
         23 . The magnet according to  claim 22 , wherein the slide comprises a first slide part and a second slide part, between which the first permanent magnet is attached. 
     
     
         24 . The magnet according to  claim 23 , wherein the slide is arranged to be movable, so that in the holding position of the magnet, the first slide part is in contact with the shell and the second slide part is in contact with the centre. 
     
     
         25 . The magnet according to  claim 22 , wherein the centre comprises a second permanent magnet, which is arranged so that the differently named poles of the first and second permanent magnet are opposite to each other. 
     
     
         26 . The magnet according to  claim 22 , wherein the magnet comprises at least one spring, which is arranged to mechanically detach the slide from the shell and the centre when the magnetic flux produced by the first permanent magnet weakens sufficiently due to the magnetic field produced by the electric magnet. 
     
     
         27 . The magnet according to  claim 22 , wherein the magnet comprises at least one sliding sleeve, which is arranged to control the movement of the slide. 
     
     
         28 . The magnet according to  claim 22 , wherein a part of the slide meant to be inside the coil of the electric magnet has a constricted shape. 
     
     
         29 . The magnet according to  claim 22 , wherein an edge of the shell meant to be in contact with the object to be gripped is bevelled to be thinner. 
     
     
         30 . The magnet according to  claim 22 , wherein the magnet comprises control means for controlling the magnetic field produced by the electric magnet. 
     
     
         31 . The magnet according to  claim 30 , wherein the control means comprise a source of electric power, such as a battery, and means for guiding electric current in a controlled manner from the electric power source to the electric magnet in order to control its function. 
     
     
         32 . The magnet according to  claim 30 , wherein the magnet comprises a wireless receiver for receiving a control signal of the control means. 
     
     
         33 . An attaching device, which comprises:
 at least one magnet according to  claim 22 , which magnet is arranged to produce a holding force, and   control means for controlling the holding force produced by the magnet.   
     
     
         34 . The attaching device according to  claim 33 , wherein the control means are arranged to control a magnetic field produced by the electric magnet of the magnet. 
     
     
         35 . The attaching device according to  claim 33 , wherein the control means are arranged so that the magnets are separately controllable. 
     
     
         36 . An attaching device, which comprises:
 a first magnet in the first end of the attaching device, which first magnet is arranged to produce a first holding force for attaching the attaching device to a working base or to another attaching device or to an object to be worked,   a second magnet in the second end of the attaching device, which second magnet is arranged to produce a second holding force for attaching the attaching device to the working base or to another attaching device or to the object to be worked, and   control means for controlling the holding forces produced by the first and second magnet;   wherein the first and/or second magnet is a magnet according to  claim 22 .   
     
     
         37 . An attaching arrangement, which comprises:
 at least one attaching device according to  claim 22 ,   a control unit for producing control signals for the magnets of the attaching devices, and   data transfer devices for transmitting the control signals to the control means of the attaching devices.   
     
     
         38 . A method for attaching to an object, which method comprises:
 attaching an attaching device according to  claim 22  to an object by means of a holding force produced by a magnet.   
     
     
         39 . The method according to  claim 38 , comprising:
 moving a slide in relation to a shell and centre, in order to close and open a circuit of the magnetic flux, i.e. in order to change the state of the magnet between a holding position and an open position,   holding the slide in connection with the shell and centre with a magnetic field of the first permanent magnet, when the circuit of the magnetic flux is closed, i.e. when the magnet is in the holding position, and   switching off the magnetic flux provided by the first permanent magnet at least partly, when necessary, by producing a magnetic field with the electric magnet, in order to change the state of the magnet to the open position.   
     
     
         40 . The method according to  claim 38 , comprising:
 producing a force with at least one spring, which force strives to mechanically detach the slide from the shell and centre when the magnetic flux produced by the first permanent magnet weakens sufficiently due to the magnetic field produced by the electric magnet.   
     
     
         41 . The method according to  claim 38 , comprising:
 monitoring movement of the slide in relation to the rest of the magnet with a sensor, and if movement is detected when the magnet is in the holding position, increasing the holding force of the magnet by giving more electric current to the electric magnet coil.