EP1776210B1 - Multipurpose fixing magnetic semi-clamp - Google Patents

Abstract

The invention relates to a multipurpose magnetized device for immobilising an object on a magnetic or ferro-magnetic surface or grasping an object. Said device includes a lever arm ( 2 ) and a magnetized surface ( 1 ) separated by a line of rotation ( 3 ). Said magnetized surface makes it possible to fix the device either to a worktop or another object, or to another magnetized semi-clamp. The device is particularly intended to fix objects to a worktop, in particular to a large worktop, or to a "magnetic" board.

Description

Technical area

The invention relates to a magnetic device for multiple use which we hereinafter call a magnetic half-clamp for immobilizing an object on a magnetic surface or constituting a clamp for grasping an object or exerting a clamping force, according to the preamble of claim 1,

Such a device is known from the document US 2,693,370 .

Magnetic surface means the surface of an object which is subjected to a magnetic force under the effect of a dipole magnetic source.

In particular, objects made of ferro-magnetic materials are part of these objects which we call the magnetic surface surface, ie surface on which a magnet can be glued by magnetic attraction.

By magnetic device is meant a device comprising magnetic materials distributed or traversed by an electric current so as to create a magnetic field characterized by the appearance of North and South poles on at least one of the surfaces of the device. We call, subsequently, such a surface of the magnetic surface device.

Prior art

The attachment of parts, sheets, fabrics or objects on a worktop is traditionally performed using fasteners integrated in the work plan. The work plan must be arranged to receive them (opening, projection, grooves for fixing the fastening means to the work plan).

The attachment points are therefore integrated in the work plan. Their position is predefined and fixed except to implement complex rail devices or sliding systems to fix a room anywhere on the worktop. These devices are then complex to to implement, especially on large work plans.

The use of fasteners based on permanent magnets is not widespread. It is limited to the use of low-intensity magnets (for example on "magnetic" boards) because of the difficulty of taking off or correctly positioning a magnet of greater intensity on a work surface.

The strong permanent magnets also cause stresses during their transport because of the permanence of the magnetic field and the attraction force resulting therefrom.

Most existing devices immobilize the object between a magnetic surface and a magnetic surface, this is the case of the device described in the patent US 6,302,363 B1 published on October 16, 2001 , of the device described in the patent US n ° 2,693,370 Published 2 Nov. 1954 or the device described in the patent EP 1 502 767 A published February 2, 2005 . The devices described in the patents US 4,971,278 Published November 20, 1990 and DE 101 48 028 A1 published on May 8, 2003 , also have a magnetized part but it is a non-magnetized part which makes it possible to fix the object to a magnetic support. They have the disadvantage of only allowing the attachment of thin objects.

Presentation of the invention

The present invention overcomes these disadvantages.

It makes it possible to overcome the difficulties associated with permanent magnets by constituting an easily removable, manipulable and transportable assembly while allowing significant attraction forces.

It also constitutes a versatile device that can be transformed into a gripping clamp by putting face to face two identical elements or not, the two jaws of the clamp not being secured by any mechanical device, their centering and their pivoting being achieved by an ingenious distribution of the magnetic masses. For this purpose, the invention relates to a device according to claim 1.

Brief description of the drawings

• Surface aimantée (1)
• Bras de levier (2)
• Ligne de pivotement (3)
• Plan de travail (4)
• Pièce (5)
• Ligne de séparation des pôles (6)
• Angle d'ouverture (7)
• Griffe (8)
• Angle formé par le bras de levier et la surface aimantée dont le sommet est la ligne de pivotement (9)
• Gorge (10)
• Pôle magnétique Nord (11)
• Pôle magnétique Sud (12)
• Axe (13)
• Bras de levier maximum (14)

The accompanying drawings illustrate the invention:

• Magnetic surface (1)
• Leverage arm (2)
• Swivel line (3)
• Work plan (4)
• Piece (5)
• Pole separation line (6)
• Opening angle (7)
• Claw (8)
• Angle formed by the lever arm and the magnetized surface whose vertex is the pivot line (9)
• Throat (10)
• North Magnetic Pole (11)
• South Magnetic Pole (12)
• Axis (13)
• Maximum lever arm (14)

Best way to realize the invention

In its simplest embodiment, shown figure 1 in profile and figure 3 in view from below, the device of the invention, which we call a magnetized half-clamp, consists of a magnetized surface (1), a lever arm (2) and a pivot line ( 3) located between the magnetized surface and the lever arm.

The magnetic surface of the magnetic half-gripper is intended to be brought into full or partial contact with a work plane or a partially or totally magnetic object (4).

The magnetic attraction force creates a tightening torque around the pivot line (3).

The worktop is a surface that is not necessarily flat.

The magnetic half-clamp allows the immobilization of the workpiece (5) on the worktop or object (4), the workpiece being wedged between the magnetized half-clamp and the worktop or object ( figure 4 ) under the effect of the magnetic force.

The lever arm (2) allows easy detachment of the clamp from the surface by pivoting about the pivot line (3) of the clamp ( figure 2 ).

The pivot line (3) is, at any time, the axis of rotation of the device passing through the contact point or points between the magnetized surface and the work plane.

The magnetized surface (1) has a line that we will call the pole separation line (6), this line being approximately the perpendicular to the magnetized surface of the barycentre of the South poles and the North poles magnetization of the surface. There is such a large South Pole "force" on one side of the pole separation line that we will find a "North Pole" force on the other side of the line, the two centers of the North Poles and South being of equal weight on the magnetized surface (1).

The shape of the lever arm (2) is chosen to allow the user to exert a force substantially orthogonal to the magnetized surface or a torque relative to the pivot line (3) of the magnetized half-gripper.

This arrangement prevents slipping of the magnetized half-clamp on the work surface when an operator exerts an action on the lever arm. The shape can be adapted according to the coefficient of friction between the work plane and the magnetic half-clamp.

According to a particular embodiment, the angle formed by the lever arm and the magnetized surface whose vertex is the pivot line (9) may have a value greater than 145 °. This particular configuration is represented on the figure 2 .

According to the invention, the line of separation of the poles (6) ( Figure 3 ) is perpendicular or near perpendicular to the pivot line (3), which may itself be aligned or approximately aligned with the maximum lever arm (14), ie the segment of the orthogonal lever arm at the pivot axis passing through the point of the magnetized half-gripper at the greatest distance from the pivot axis.

This configuration makes it possible to have a continuous attraction force between the magnetized surface and the work surface as the opening angle (7) between the magnetized half-clamp and the working plane increases. It further avoids that the magnetic half-clamp slides on the worktop when it opens, the pivot line remaining in contact with the worktop.

• la ligne de pivotement (3) peut être matérialisée par une arrête de la demi-pince magnétique, en particulier si cette ligne de pivotement est utilisée pour positionner des objets coincés sous la demi-pince magnétique
• la ligne de pivotement peut présenter une section courbe, cette section courbe pouvant comporter des dispositifs, roulettes, billes, ou autres sur son bord extérieur, facilitant le déplacement de la demi-pince une fois celle-ci ouverte sur le plan de travail
• la ligne de pivotement peut présenter une gorge (10) permettant de caler la demi-pince aimantée sur le plan de travail ou l'objet ou de caler deux demi-pinces aimantées entre elles en introduisant un axe (13) dans la gorge (figures 20 à 25, vue de profil)

According to a particular embodiment, the pivot line (3) can be a straight line. This configuration makes it possible to position the magnetic half-gripper on the work plane, then to open it then to slide an object between the magnetic half-gripper and the work plane which is wedged against the pivot line (3).
According to the particular modes of realization adopted:

• the pivot line (3) can be indicated by a stop of the magnetic half-gripper, in particular if this pivot line is used to position objects trapped under the magnetic half-gripper
• the pivot line may have a curved section, this curved section may include devices, wheels, balls, or other on its outer edge, facilitating the movement of the half-gripper once it open on the work plane
• the pivot line may have a groove (10) for wedging the magnetized half-clamp on the work surface or the object or wedge two magnetized half-clamps together by introducing an axis (13) into the groove ( Figures 20 to 25 , Profile view)

According to a particular embodiment ( figures 14 , 16 , 18 and 19 , seen from below the magnetic surface of the device), the pole separation line (6) can constitute approximately an axis of symmetry of the geometry of the magnetized surface (1), the magnetic fields passing through two symmetrical surface elements with respect to each other. to the polar separation line being opposed with consequently a form of antisymmetric distribution of the North and South poles on either side of the line of separation of the poles.

This arrangement then also makes it possible to constitute a magnetized clamp by assembling two identical or different magnetized half-clips ( figure 9 ). The symmetry of the device allows in this configuration an automatic centering of the two half-clips relative to each other, the separation lines of the poles of the two half-clips being approximately merged when the clamp is closed. The pivot line is then the opening axis of the clamp.

The correspondences between South poles and North poles when two half-pliers are assembled according to this particular mode are represented in two particular configurations on the figures 15 and 17 in view from below. The Figures 18 and 19 present two other examples of possible pole distributions also in view from below.

This arrangement also facilitates the transport of magnetic half-clips, the half-clips being transported in pairs, glued against each other.

According to a particular embodiment ( figures 5 , 6 , 7 and 8 ), the magnetized half-clamp may comprise a claw elastic (8) for fixing thick parts while maintaining a high clamping force. The elasticity of the elastic claw (8) is adapted to the attraction force developed by the magnetized surface (1), the lever arm (2) and the thickness range for which the device operates.

The device according to the invention is particularly intended for fixing objects on a work plane, in particular a large worktop, or on a magnetic board.

Claims (5)

1. A magnetic holding or blocking device made up of a magnetized semi-clamp, comprising a permanent or not permanent magnetic component which creates a dipolar or multipolar magnetic flux on at least one of the device surfaces, surface called magnetic surface (1), a leverage arm (2) and a swivel line (3) situated between the leverage arm (2) and the magnetic surface (1), wherein the parting line of poles (6) defined as the perpendicular bisector of the barycenters of the south poles and north poles of the magnetic surface is approximately the line of highest leverage of the part and is also perpendicular or nearly perpendicular to the device line of swivel (3) round the magnetized surface (1).
2. The device as claimed in claim 1, wherein the parting line of poles (6) is also approximately the geometrical axis of symmetry of the magnetic surface (1).
3. The device as claimed in anyone of the preceding claims, wherein the magnetic distribution on the magnetic surface is exactly or approximately antisymmetric with regard to the parting line of poles (6), i.e. magnetic flux leaving the surface in two symmetrical zones with regard to the line (6) are of the same intensity and in opposite directions.
4. The device as claimed in anyone of the preceding claims, wherein the swivel line (3) covers a curved surface including, on its part external to the magnetic surface (1), components such as ball bearings, casters or other ones facilitating the sliding of the device on a contact surface.
5. The device as claimed in anyone of the preceding claims, wherein the swivel line (3) has a groove (12).

Images