GB2194563A

GB2194563A - A clip for a tentering frame chain

Info

Publication number: GB2194563A
Application number: GB08715887A
Authority: GB
Inventors: Karl Grafen
Original assignee: H Krantz GmbH and Co
Current assignee: H Krantz GmbH and Co
Priority date: 1986-08-29
Filing date: 1987-07-06
Publication date: 1988-03-09
Also published as: BR8704402A; FR2603267A1; IT8721744A0; DE3629508A1; ATA141887A; GB8715887D0; CH672479A5; DE3629508C2; AT391491B; JPS6366056A; ES2008140A6; IT1222559B

Abstract

A two-armed clip 3 for a tenter frame chain is swingably mounted in. a clip body. Arm 8 of the clip 3 is influenced by a permanent magnet 12 to swing arm 6 to clamp a fabric web 1 against the underside of a part (2) of the clip body. A profile piece (9) that is attracted to the magnet has one surface lying in a plane perpendicular to the swivel plane of the clip (3), while a further surface thereof is arranged perpendicularly thereto at a constant distance from a surface of the magnet (12) over at least a part of the swivel arc. Thus the clip 3 remains in the region of influence of the magnet 12 for over at least said part. The profiled piece 9 may be secured to arm 6 of the lever 3 while the clip body supports the magnet 12 or vice versa. The piece 9 may be in the shape of an angle piece, a U-piece or a cup. <IMAGE>

Description

SPECIFICATION A clip for a tentering frame chain The invention relates to a clip for a tentering frame chain comprising a clip body in which a two-armed clip, lever is swingably mounted.

The free end of one arm of the clip lever provides a clamping strip which is swingable towards the underside of a plate-shaped part of the clip body. The other arm of the clip lever is exposed to the force field of a permanent magnet whereby the clip lever is swingable against the force of gravity into its clamping position. As the clip lever swings towards its clamping position, the distance between one surface of the permanent magnet and an opposing surface of a profile piece, which is associated with the permanent magnet as reciprocal pole, is shortened in accordance with the approach of the clamping strip to the underside of the plate-shaped part of the clip body.

A clip of this type, such as that disclosed in German Patent Specification 05 34 19 396, has the advantage of slight overall height, because the edge margins of the fabric web that is to be transported through the tentering frame in spread condition are pressed against the plate-shaped part of the clip body from below by the clamping strip of the clip lever so that component parts which project upwards beyond the level of the plate-shaped part are not necessary. In contrast, in conventional clips the plate-shaped part of the clip body serves as a so-called clip table, above which the clip lever is swingably mounted, in order to clamp the edge margins of the fabric web securely against the upper side of the clip table.As a result of the lower overall height of the clip, the spacing of nozzle mouths, by way of which treatment medium is supplied to the fabric web secured in the tentering frame, can be reduced, so that the efficiency of the treatment can be improved.

If the fabric web is to be clipped-in from below, without an additional counter-weight being mounted on the clip lever or a spring acting on the clip lever, another means has to be provided in order to transfer the clip lever, against the force of gravity, into its clamping position. The use of a counter-weight is unfavourable as it leads to higher inertia of the clip lever, greater overall weight and an increased space requirement. The use of a spring has the disadvantage that in the event of a spring breakage the function of the clip is completely prevented.

For the clip known from German Patent Specification 05 34 19 396 it has already been proposed to use a permanent magnet to exert a force effective to swing the clip lever against the force of gravity into its clamping position. In this respect, a profile piece consisting of a flat plate is associated with the permanent magnet as reciprocal pole.

In the case of the known clip equipped with a permanent magnet, it has proved to be disadvantageous that, with increasing aperture angle of the clip lever and thus increasing distance between the permanent magnet a#nd the reciprocal pole, the magnetic force acting at the clip lever decreases. This has a particularly adverse effect when fabric web of thicker quality is to be clipped in place in that the magnetic force may be insufficient to hold the clip in its clamping position.

The object of the invention is to improve a clip, of the kind described at the beginning hereof, in such a way that the magnetic force affecting the clip lever can be kept almost constant over a greater region of the swivel arc of the clip lever.

With this object in view, the invention proposed a clip of the kind mentioned in the first paragraph characterized in that one further surface of the permanent magnet and one further surface of the profile piece are so aligned that the substantially perpendicular distance between these surfaces is constant at least over an end section of the swivel arc through which the lever arm is capable of swinging.

The gap between the further surfaces of the permanent magnet and the profile piece is preferably of comparatively slight width. Thus, over a comparatively large end section of the swivel arc of the clip lever the said further surface of the profile piece lies in the region of influence of the permanent magnet (by virtue of the further surface of the permanent magnet lying opposite it at constant spacing) so that the transfer of the clip lever into its clamping position is assisted, before the distance between the other surfaces of the permanent magnet and of the reciprocal pole, which lie in perpendicular planes to the swivel plane, has reduced sufficiently for magnetic effect therethrough. Moreover, the distance between these further surfaces is small enough to trigger a direct magnetic force effect via these surfaces.

Preferably, the profile piece serving as reciprocal pole, which is fastened either to the lever arm which is influenced by the force field of the magnet or to the clip body, has surfaces extending at right angles to one another, and the permanent magnet which is fastened to the clip body or, respectively, to the lever arm influenced by the force field of the magnet, has two surfaces which extend correspondingly at a right angle to one another.

Thus, in a simple embodiment the profile piece serving as reciprocal pole, may consist of an angle profile piece one limb of which butts against the relevant arm of the clip lever in a plane extending perpendicular to the swivel plane of the clip lever, whilst the other limb is aligned parallel to the swivel plane of the clip lever. To further improve the early magnetic effect, instead of an angle profile piece, a U-profile piece may, for example, be provided as reciprocal pole. Such a U-profile piece will have its cross-piece butting against the relevant arm of the clip lever in a plane extending perpendicular to the swivel plane of the clip lever, whilst the two limbs of the profile piece both extend parellel to the swivel plane of the clip lever so that the permanent magnet is received between them at least over an end section of the swivel arc of the clip lever.Alternatively it is possible to design the profile piece, serving as the reciprocal pole, in a cup-shaped manner, with the permanent magnet being received or inserted into the cup cavity, which is open on one side in the swivel direction, as the clip lever moves to its closure position.

The permanent magnet may be designed as a cylinder or a cube or a parallelepiped, so long as it interfits appropriately with the profile piece acting as reciprocal pole.

Indeed, a particularly good effect for the transfer of the clip lever into its clamping position can be achieved in cases where the shape of the profile piece and of the permanent magnet are co-ordinated to one another in a matrixor, respectively, patrix-shaped manner, i.e. where projections of one are closely matched to the shape of recesses in the other and are adapted to be inserted therein as the clip lever moves towards its closure position.

Three exemplified embodiments of a clip in accordance with the invention are shown in the drawings, in which: Fig. 1 is a side view of a first embodiment of the clip of the invention; Fig. 2 is an enlarged fragmentary cross-section along the plane indicated in Fig. 1; and Figs. 3 and 4 are views corresponding to Fig. 2 of embodiments having differently designed reciprocal poles.

As indicated in Fig. 1, the edge margin of a fabric web 1 is clamped firmly against the underside of a plate-shaped part 2 of a clip body by means of a two-armed clip lever 3 which is swingable about an axis 4 mounted between supporting arms 5 which are integrally formed on the clip body.

The free end of the upwardly directed lever arm 6 forms a clamping strip 7, by means of which the edge of the fabric web 1 can be pressed against the underside of the plateshaped part 2.

Fastened laterally to the downwardly directed lever arm 8 is a profile piece 9 (Fig. 2), or 10 (Fig. 3), or 11 (Fig. 4) which serves as reciprocal pole for a permanent magnet 12 which is mounted on the underside of the supporting arms 5 by way of retaining elements 13.

Whilst the permanent magnet 12 in each of the exemplified embodiments is cylindrical in design, the profile piece 9 in Fig. 2 has the shape of an angle piece, the profile piece 10 in Fig. 3 has the shape of a U-piece and the profile piece 11 in Fig. 4 has the shape of a cup. In each case, surfaces, of the permanent magnet 12, which extending at right angles to one another, lie opposite corresponding surfaces of the profile piece 9 or 10 or 11, which also extend at right angles to one another.

In this way, at least over an end section of the swivel arc of the clip lever 3, a gap of constant width is ensured between that surface of the permanent magnet 12 which extends parallel to the swivel plane and the corresponding surface of the profile piece 9, 10 or 11, which also extends parellel to the swivel plane.

Other variations are possible. For example the magnet may be provided on the lever and the profile piece on the clip body.

Claims

1. A clip for a tentering frame chain comprising a two-armed clip lever swingably mounted on a clip body, the free end of one arm of the lever providing a clamping strip which is swingable towards the underside of a plate-shaped part of the clip body, whilst the other arm of the lever is capable of being influenced by the force field of a permanent magnet so as to swing the clip lever against the force of gravity into its clamping position, in which respect the distance between one surface of the permanent magnet and one surface of a profile piece associated therewith as reciprocal pole is shortened as the clamping strip approaches the underside of the plateshaped part, characterized in that one further surface of the permanent magnet and one further surface of the profile piece are so aligned that the substantially perpendicular distance between these surfaces is constant at least over an end section of the swivel arc through which the lever arm is capable of swinging.

2. A clip as claimed in claim 1, characterized in that the profile piece serving as reciprocal pole is fastened either to the lever arm which is influenced by the force field of the permanent magnet or to the clip body and has surfaces extending at right angles to one another and the permanent magnet is fastened either to the clip body or, respectively, to the lever arm influenced by the force field of the magnet and has two surfaces which extend correspondingly at a right angle to one another.

3. A clip as claimed in claim 1 or 2, characterized in that the permanent magnet is designed as a cylinder, or a cube, or a parallelepiped.

4. A clip as claimed in any of claims 1 to 3, characterized in that the shape of the profile piece and the shape of the permanent magnet are co-ordinated to one another in a matrix- or, respectively, patrix-shaped manner.

5. A clip for a tentering frame chain com prising a two-armed clip lever swingably mounted on a clip body, one arm of the lever being exposed to the force field of a permanent magnet in such a manner as to cause swinging of the clip lever against the force of gravity to bring the free end of the other arm towards the underside of a plate-shaped part of the clip body, characterized in that one surface of the permanent magnet and one surface of an associated profile piece acting as reciprocal pole are so aligned that the distance between these surfaces is substantially constant at least over an end section of the swivel arc of the clip lever.

6. A clip for a tentering frame chain substantially as hereinbefore described with reference to and as illustrated in Figs. 1 and 2, or Fig. 3, or Fig. 4 of the accompanying drawing.