GB1572327A - Device for sealing joints or connections in a continuous length of material - Google Patents

Description

(54) DEVICE FOR SEALING JOINTS OR CONNECTIONS IN A CONTINUOUS LENGTH OF MATERIAL (71) I, SIEGFRIED MULLER, a German citizen, of Dahlienstr. 25, 5800 Hagen 8, Germany, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: - The invention relates to a device for sealing a joint in a continuous length of material, with a slotted envelope of substantially sleeve form of heat-shrinkable material, the longitudinal edges of which are pressed towards one another to maintain a seal therebetween by a substantially C-shaped clamping rail.

Known devices of this kind (German Patent Specification 1,525,815) possess bead-like longitudinal edges which are pressed with their back surfaces fitting against one another without gaps by the C-shaped clamping rail, in which case these edge beads must have a considerable thickness in order to guarantee a satisfactory seal. The production of such slotted envelopes with longitudinal edges having edge beads is however complicated and expensive, when such parts are produced by the synthetic plastics injection moulding method and, where possible a uniform wall thickness is sought. Moreover the application of the C-shaped clamping rail requires great force, especially in the case of a lengthy seam course, since after the lateral pushing of the clamping bar on to the edge beads the full clamping effect must still be present, for which reason in the normal case a special tool is required for this purpose. Moreover in some cases it has appeared that in the application of the heat necessary for the subsequent operation of shrinking the envelope, as a result of excessive heating the synthetic plastics material of the edge beads can be pulled out of the C-shaped clamping rail, whereby the entire seal is broken.

The problem of the invention is the provision of a solution which primarily simplifies the production of slotted envelopes of the kind in question, excludes incorrect functions as a result of unintentional excessive heating in the region of the seam and provides the prerequisites for an especially good seal with easy and rapid fitting of the individual necessary parts before the shrinking operation.

According to the invention, this problem is solved by a device for sealing a joint in a continuous length of material, comprising a slotted sleeve form for embracing the continuous length and made of heat-shrinkable material, longitudinal out-turned edge sections formed along each side of the slot, said edge sections being pressed towards one another to maintain a seal therebetween by the action of a substantially C-shaped clamping rail, and two profiled clamping strips respectively arranged on opposite sides of the longitudinal edge sections with the C-shaped clamping rail engaging externally round the profiled clamping strips with the edge sections extending between them, so as at least partially to cover the clamping strips and edge sections, the edge sections each having the same thickness as that of the material of the entire sleeve.

By reason of this formation the C-shaped clamping rail can press towards one another the faces of the longitudinal edge sections of the envelope which are directly towards one another and situated between the profiled clamping strips so as to act in exactly the same way as in the case of a one-piece formation of an envelope with longitudinal edges having edge beads, so that the production of the entire envelope is substantially simplified and thus can take place more economically.

For the achievement of a good seal it has further proved especially advantageous to provide the web of an I-shaped sealing strip between the longitudinal edge sections of the envelope, the flanges of which sealing strip on the one hand overlap the longitudinal edge sections inside the envelope and on the other hand fit between the clamping rail and the edge sections.

Preferably, each clamping strip is formed with a flat face engaging the associated out-turned edge section and a rounded face remote from the edge section, the flat and rounded faces being joined by outer and inner faces, the outer face being substantially at right angles to the flat face, and the C-shaped clamping rail being shaped to curve round the rounded faces of the clamping strips.

Thus in fact the object is achieved that after the clamping rail has been pushed over the above-described parts and when the shrinking of the envelope takes place along the joint to be sealed, a rotating movement of the clamping strips about their outer corner edges takes place as they approach one another while moving slightly inwards as a result of the tensile forces exerted upon the longitudinal edges by the shrinking. Therefore, the region of the outer corner edges of the clamping strips clamping of the longitudinal edges occurs, and particularly if a sealing strip is interposed, an excellent sealing effect is produced. As can be seen with such a formation, the individual parts can initially be formed with such play that they can be fitted together before the shrinking operation without great expenditure of force and thus without special tools.

In order to ensure that the longitudinal edge sections are not pulled out between the clamping strips, it is advisable to provide each clamping strip with a groove for the reception of a flange on the association longitudinal edge section which is bent over twice at right angles to provide the flange. Naturally such as an unintentional pulling out of the longitudinal edge sections between the clamping strips can also be avoided by a friction-intensifying formation of the clamping strips in the region of their contact with the longitudinal edge sections for example by appropriate fluting of the relevant clamping strip sur faces.

Aluminium has provide an especially suitable material for the clamping strips, since on the one hand this is light and on the other hand it possesses good strength properties, which is advantageous especially when substantially rectilinear joint seams are desired. Naturally suitable heat-stable synthetic plastics materials could also be used for the clamping strips, which have a certain measure of flexibility and are therefore useful for joint seams following a curved path, for example in a cable joint box.

Finally for the latter case the clamping strips can also be provided with transversely directed incisions, in the same way as in known curved C-shaped connection clamping rails used in the aforesaid prior art designs.

The invention is described with greater detail below by way of example with reference to the accompanying drawing, which is a transverse section through a sealing device.

In the example shown in the drawing a slotted envelope 1 consisting of heatshrinkable synthetic plastics material is provided with longitudinal edge sections 2 of equal thickness which are bent radially outwards and then twice at right angles in substantially C-form. A profiled clamping strip 3 of aluminium is arranged on each of the two sides of the longitudinal edge sections 2 and between the longitudinal edge sections 2 there is arranged the web 4 of a substantially I-shaped sealing strip, the inner flanges 5 of which internally overlap the longitudinal edge sections 2 and the outer flanges 6 of which engage over the outer parts of the longitudinal edge sections 2.

In each clamping strip 3 a groove 7 is formed into which an outer flange portion 8 of the associated longitudinal edge section 2 extends.

Finally over the clamping strips 3 and the longitudinal edge sections 2 at least partially covering these, also the sealing strip, there is pushed a C-shaped clamping rail 9.

As can be seen the outer surfaces of the clamping strips 3 and the adjacent inner surfaces of the C-shaped clamping rail 9 are of rounded formation and the inner surfaces of the clamping profiles facing one another are made flat, so that when shrinking as a result of application of heat to the envelope 1, occurs tensile forces then exerted upon the longitudinal edge section 2 tend to rotate the profiled clamping strips 3 towards one another. The result is that in the region of the upper inner corner edges of the clamping strips the longitudinal edge sections 2 and the web 4 of the sealing strip are pressed closely together between the clamping strips 3 whereby an excellent sealing effect is obtained.

By reason of this formation it can also be seen that the individual parts can be initially formed with such adequate play that their assembly or fiting together is possible without the application of excessive force, since the actual sealing effect is brought about only, by the above mentioned rotation of the clamping strips during the shrinking process.

When the device is applied to a curved joint the profiled clamping strips are provided with transversely directed incisions to enable them to bend so as to follow the path of the curved joint.

WHAT I CLAIM IS: - 1. A device for sealing a joint in a continuous length of material, comprising a slotted sleeve for embracing the continuous length and made of heat-shrinkable material, longitudinal out-turned edge sections formed along each side of the slot said edge sections being - pressed towards one another to maintain a seal therebetween by the action of a substantially C-shaped clamping rail, and two profiled clamping strips respectively arranged on opposite sides of the longitudinal edge sections with the C-shaped clamping rail engaging externally round the profiled clamping strips with the edge sections extending between them, so as at least partially to cover the clamping strips and edge sections, the edge sections each having the same thickness as that of the material of the entire sleeve.

2. A device according to Claim 1, in which the web of an I-shaped sealing strip is located between the edge sections of the envelope, the inner flanges of the sealing strip overlapping the longitudinal edge sections where they join the envelope and the outer flanges of the sealing strip extending between the outer edges of the edge sections and the clamping rail.

3. A device according to Claim 1 or Claim 2, in which each clamping strip is formed with a flat face engaging the associated out-turned edge section and a rounded face remote from the edge section, the flat and rounded faces being joined by outer and inner faces, the outer face being substantially at right angles to the flat face, and the C-shaped clamping rail being shaped to curve round the rounded faces of the clamping strips.

4. A device according to any one of the preceding claims, in which each clamping strip is formed with a longitudinal groove opening outwardly into the outer face of the strip, and each edge section is bent sot as to extend over the associated clamping strip as far as the groove therein and is further bent to form a flange fitting into the groove.

5. A device according to any one of the preceding claims, in which the profiled clamping strips are made of aluminium.

6. A device according to any one of the preceding claims, in which each profiled clamping strip is provided with transversely directed incisions.

7. A device substantially as hereinbefore described with reference to the accompanying drawing.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. mentioned rotation of the clamping strips during the shrinking process. When the device is applied to a curved joint the profiled clamping strips are provided with transversely directed incisions to enable them to bend so as to follow the path of the curved joint. WHAT I CLAIM IS: -

1. A device for sealing a joint in a continuous length of material, comprising a slotted sleeve for embracing the continuous length and made of heat-shrinkable material, longitudinal out-turned edge sections formed along each side of the slot said edge sections being - pressed towards one another to maintain a seal therebetween by the action of a substantially C-shaped clamping rail, and two profiled clamping strips respectively arranged on opposite sides of the longitudinal edge sections with the C-shaped clamping rail engaging externally round the profiled clamping strips with the edge sections extending between them, so as at least partially to cover the clamping strips and edge sections, the edge sections each having the same thickness as that of the material of the entire sleeve.

2. A device according to Claim 1, in which the web of an I-shaped sealing strip is located between the edge sections of the envelope, the inner flanges of the sealing strip overlapping the longitudinal edge sections where they join the envelope and the outer flanges of the sealing strip extending between the outer edges of the edge sections and the clamping rail.

3. A device according to Claim 1 or Claim 2, in which each clamping strip is formed with a flat face engaging the associated out-turned edge section and a rounded face remote from the edge section, the flat and rounded faces being joined by outer and inner faces, the outer face being substantially at right angles to the flat face, and the C-shaped clamping rail being shaped to curve round the rounded faces of the clamping strips.

4. A device according to any one of the preceding claims, in which each clamping strip is formed with a longitudinal groove opening outwardly into the outer face of the strip, and each edge section is bent sot as to extend over the associated clamping strip as far as the groove therein and is further bent to form a flange fitting into the groove.

5. A device according to any one of the preceding claims, in which the profiled clamping strips are made of aluminium.

6. A device according to any one of the preceding claims, in which each profiled clamping strip is provided with transversely directed incisions.

7. A device substantially as hereinbefore described with reference to the accompanying drawing.