APPARATUS FOR MAKING CONICAL BELLOWS

Abstract

The invention is directed to an apparatus for making conical bellows for air springs. The apparatus includes a clamping/spreading device transferable between first and second end positions corresponding to an introduction position and a vulcanization position, respectively. The external diameter of the device in the first end position is less than the external diameter thereof of the second end position. The device has clamping segments which in the introduction position are converged so that the external diameter of the device enables an air spring bellows preform to be pushed over the device, and the clamping segments in the vulcanization position are diverged increasing the external diameter of the device so that the bellows preform is pressed tightly against the corresponding external form from the inside. Open gaps because of the enlargement of the external diameter of the device remain between the clamping segments.

Claims

1. An apparatus for making a conical bellows for an air spring, the apparatus comprising: a tool defining a conical surface for receiving said conical bellows thereagainst; a clamping/spreading device transferable between first and second end positions; said device having a plurality of clamping segments which are converged in said first end position to conjointly define a first outer diameter of a magnitude to permit pushing a conical bellows preform over said device thereby introducing said device into said conical bellows preform; said plurality of clamping segments being movable so as to be diverged in said second end position wherein said segments conjointly define a second outer diameter greater than said first outer diameter so as to permit said bellows preform to be pressed by said clamping segments tightly against said conical surface from within said bellows preform during vulcanization; and, each two mutually adjacent ones of said clamping segments conjointly defining an open gap therebetween because of the enlargement to said second outer diameter in said second end position.

2. The apparatus of claim 1, wherein the open gaps each have a width lying in a range of 1 to 30 mm in said second end position.

3. The apparatus of claim 1, wherein the open gaps each have a width lying in a range of 3 to 25 mm in said second end position.

4. The apparatus of claim 1, wherein said clamping segments are at least three in number.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The invention will now be described with reference to the drawings wherein:

[0017] FIG. 1 is a schematic, in longitudinal section, of an apparatus for vulcanizing air spring bellows, having a bellows preform inserted;

[0018] FIG. 2 shows the tool for vulcanizing air spring bellows, having a fully vulcanized air spring bellows, in a longitudinal section;

[0019] FIG. 3 shows a plan view of a clamping/spreading device according to the invention, in a converged state; and,

[0020] FIG. 4 shows the clamping/spreading device in a diverged state.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0021] The apparatus for vulcanizing air spring bellows is schematically shown in FIG. 1 and includes a tool 1. An air spring preform 2, here shown as an upper portion, has a bead 3 having an embedded core 4. The bead 3 is guided toward a conical form 5.

[0022] Schematically shown clamping segments 6, of which only two segments are shown here, of a clamping/spreading device (not shown in more detail in FIG. 1) are converged in such a manner that the bellows preform 2 by way of the opening 7 of the latter has been capable of being pushed over the clamping segments 6.

[0023] The air spring bellows 2 is shown as a fully vulcanized portion in FIG. 2. The bead 3 by way of the presently diverged clamping segments 6 of the clamping/spreading device is pressed against the conical shape 5 of the tool 1. To this end, the clamping segments 6 are diverged such that a compression of the bead 3 takes place.

[0024] Diverging the clamping segments 6 leads to gaps between the individual clamping segments 6, rubber material of the bellows 2 having penetrated the gaps in the vulcanization. The gaps are not visible in FIG. 2. The rubber that has penetrated the gaps forms protuberances 8 which are directed toward the interior of the bellows 2.

[0025] A plan view of a clamping/spreading device 9 according to the invention is shown in FIG. 3. The clamping/spreading device 9 has eight clamping segments 6 which here are shown in a converged state.

[0026] The clamping/spreading device 9 is likewise shown in a plan view in FIG. 4. The clamping segments 6 here are shown as diverged. The clamping/spreading device 9 between the clamping segments 6 has gaps 10 which have been created by diverging the clamping segments 6. As is shown in FIG. 2, the gaps 10 lead to the protuberances 8 of the rubber material. The protuberances 8 are not visible in FIG. 4.

[0027] The apparatus according to the invention enables the vulcanization of air spring bellows without heating bellows in a simple manner, wherein the clamping/spreading device is of a very simple construction.

[0028] It is understood that the foregoing description is that of the preferred embodiments of the invention and that various changes and modifications may be made thereto without departing from the spirit and scope of the invention as defined in the appended claims.

LIST OF REFERENCE SIGNS

[0029] (Part of the Specification)

[0030] 1 Air spring bellows vulcanizing tool

[0031] 2 Air spring bellows

[0032] 3 Bead of the air spring bellows 2

[0033] 4 Core of the bead 3

[0034] 5 Conical shape of the tool 1

[0035] 6 Clamping segments

[0036] 7 Opening of the air spring bellows 2

[0037] 8 Protuberances

[0038] 9 Clamping/spreading device

[0039] 10 Gaps between the clamping segments 6