DE3012387A1 - Rubber sealing strips butt-jointed - by vulcanising transverse disc between them - Google Patents

Abstract

A method of butt-jointing rubber strips or strands, esp. sealing strips of vulcanised rubber, consists of inserting between the ends of the strips a transverse disc of vulcanisable sealing material, then vulcanising the two strip ends to this. In the preferred apparatus, two sets of clamping jaws for gripping the strips have fixings for mounting the transverse disc and are longitudinally adjustable so that they can be brought together to vulcanise this disc to the strips.

Description

Method and device for connecting the ends of strand-

or strip-shaped rubber articles with one another. The invention relates on methods of joining the ends of rope or strip-shaped rubber articles, in particular of profiled sealing strips with one another and on devices to carry out such procedures.

For example, the doors, windows and trunk lids on motor vehicles, but also door and window openings or panes in buildings, locking lids or movable flaps on larger devices, mechanical equipment, etc. are often bordered by rubber sealing strips, due to their dual function - tight press fit on one side and secure seal on the other - mostly have a comparatively complicated and rugged cross-sectional shape. Their production in the required quantities is economically justifiable usually only possible with extrusion presses, with large, almost unlimited lengths straight, biPgsampr profile strips or strands arise. For the needs in practice, the sealing strips supplied in the fully vulcanized state are used cut in measured lengths and by joining their ends to preform one with the other to form a ring-like, self-contained sealing frame. There diP frames are inevitably subjected to strong tensile stresses already during installation, is the flawless quality of the Connection point of coarse Significance for the usability of the seals. The usual procedures up to now e.g. with a multi-layer application of an adhesion promoter on the adhesive surfaces and subsequent vulcanization, injection of blank size ~ with increased Pressure between the ends or prior gluing in the still unvulcanized Condition of the profile strips were fraught with uncertainties and closed next often unsatisfactory results, the compulsion to make costly reworking and other disadvantages. In practice, therefore, the Desire for an operationally safe, ultimately reliable and at the same time economical Connection procedure. Meeting this need is the object of the invention to watch.

According to the invention, the methods described at the outset are characterized Kind in that between the ends of two vulcanized sealing strips a the end faces of the strips with an oversize vulcanizable disk Sealing material inserted and producing an adhesive connection after both Sides being vulcanized.

The invention opens up surprisingly advantageous possibilities for making the connections even for complex or large-area profile strips and also those with relatively thin-walled, lobed, flexible webs, the were previously considered particularly difficult to process. This is true for both straight lines ge as well as for miter connections, i.e. also for assembling of the sealing strips with bevel cut end faces, as it is used to form cornering is necessary. The vulketization connection meets all requirements, which are made in terms of their strength during assembly and use of the seals. Instead of a liquid or paste-like glue with its side effects like Smearing of the forms, weak points in the raft surface, running on the outer surface the ridges, hard-to-remove shoots and the like act as a compact disc Raw material introduced into the parting line as a reliable adhesion promoter without the otherwise inevitable disadvantages. Your versus one Spreading a much greater layer thickness also bridges larger local distances between the adhesive surfaces and therefore permitted without impairing the work result Gross inaccuracies in the previous cut and in the surface properties of the ledge ends. For this reason there is a certain layer thickness of the pane, which are still clearly above the liquid even with a repeated application Adhesive thickness to be achieved is not to be undercut. A somewhat foil-like one Thickness measurement on the order of a few tenths of a mm up to a maximum 1 mm has been found to be sufficient for all practical cases.

The quality of the compounds produced according to the invention is such that the excess material still adhering outside in a single operation the bar circumference down to the finest profile ramifications can be demolished.

There is no need for other reworking at all.

An apparatus for performing the method according to the invention expediently contains two heatable ones which receive the end sections of the sealing strips Shapes, which are designed with a removable upper part and longitudinally against each other adjustable and on the facing open end faces with the discs are provided in front of the profile opening fixing retaining means. Are beneficial the profile openings in the facing end faces of the shapes of cutting edge edged over the end faces rising marginal edges, while after another Part of the feature of the invention, the holding means as provided on the upper part of one form, the discs piercing and in the state of greatest approximation of both shapes in recesses dipping pins could be formed in the top of the other shape.

The invention is based on an exemplary embodiment in the drawing schematically illustrated device.

The drawing shows in Fig. 1 to 3 the device in side view in different states of use.

DiP drawn device contains two open forms on both sides 4, 5, both of which consist of three molded parts that can be folded down from one another, namely assemble the lower parts 41, 51, the middle parts 52, 52 and the upper parts 43, 53 and which are adjustable in the longitudinal direction relative to one another on a common guide 6 are arranged. For this purpose, the movable attachment, for example of the mold, is sufficient 5, while in contrast, the mold 4 with its lower part 41 immovable on the Guide 6 can be attached. The one with electrical heating elements not shown provided molds are for receiving and sealingly enclosing the end portions of two Rubber sealing strips 7 of the cross-sectional shape indicated in the right part of the figure in FIG. 1 set up, for whatever purpose their three-part training with two Mold parting planes is necessary. For other, simpler molding profiles, however, you can a two-part design with just a single parting line is sufficient. In the end face of the upper mold part 43 facing the mold 5 there are a or tDhrvre tapered mounting pins 8 firmly inserted, which Autnahmobohrurgpn 9 in the The end face of the upper mold part 53 is closed to the front. The profile opening of both forms 4, 5 is on the peripheral facing face of its individual parts of circumferential Cutting edges 14, 15 bordered.

To use the device shown, they are to each other connecting fully vulcanized rubber sealing strips 7 in the largest distance located and opened forms 4, 5 and inserted until they are flush their smoothly cut end faces advanced (Fig. 1). After closing the Forming and interlocking your molded parts with each other becomes one of the vulcanizable Slice material cut disc 10 inserted between the molds 4, 5 and hung loosely by impaling on the mounting pins 8 in front of the profile openings (Fig.

2). The disc 10, for example by parting from an extruded cylindrical rod can be obtained, has a layer thickness of an order of magnitude of about 0.5 mm and is dimensioned in terms of their surface size so that they the profile openings over their entire circumference with ample excess covered. With the subsequent moving together of the two forms 4, 5 according to FIG. 3, sets the vulcanization of the disc 10, which at the same time to a firmly adhering cohesive Binding leads to the ends of the ledges abutting on both sides. Any excess disc material is separated from the abutting cutting edges 14, 15 of the molds, or it can also be removed by hand later if necessary.

After the vulcanization, the sealing strips 7 can the initially radially open forms 4, 5 can be removed ready for use.

Claims (4)

Claims: X method for connecting the ends of strand- or strip-shaped rubber articles, in particular profiled sealing strips with each other, characterized in that between the ends of two vulcanized Sealing strip is a disc that overlaps the end faces of the strips with an excess vulcanizable sealing material inserted and creating an adhesive connection is vulcanized on both sides. 2. Apparatus for performing the method according to claim 1, with two diF end sections of the sealing strips receiving heated molds, marked by this, that the molds (4, 5) formed with a removable upper part (47, 53) in the longitudinal direction adjustable against each other and with the open end faces facing each other the discs (10) are provided in front of the profile opening fixing means. 3. Apparatus according to claim 2, characterized in that the holding means than provided on the upper part (43) of one mold (4) which pierces the disks (10) and when the two forms (4, 5) are as closely approximated as they are in recesses (9) in the upper part (53) of the other shape (5) dipping pins (8) are formed. 4. Device according to claims 2 and 3, characterized in that that the profile openings in the facing end faces of the molds (4, 5) of edge edges (14, 15) rising like a cutting edge over the end faces are bordered.