DE102012109711A1 - Device for bladderless vulcanization of pneumatic spring blank used in commercial vehicle, has pneumatic spring indication bulge whose conical sealing surface is supported on lid to perform emerging material expulsion in joint region - Google Patents

Abstract

The device (1) has a pneumatic spring blank (2) that is determined to be closed by a lid vulcanization mold (6) in which each end is provided with an annular contour insert (7). The cover and contour insert having complementary conical surfaces (8) are adapted in specific shape during vulcanization. The conical sealing surface (4) of a pneumatic spring indication bulge (3) in the sealing region is supported on the lid. The emerging material expulsion through sealing gaps (10) in the joint region between a cover (5) and contour insert is performed and recorded in a cavity.

Description

The invention relates to a device for vulcanization of a pneumatic spring blank for an air spring bellows, wherein the air spring blank is already provided at its two ends with a Luftfederbalgwulst, seen in the cross section after vulcanization inside, d. H. to the later air spring interior has directed conical sealing surfaces, wherein the air spring blank is surrounded during vulcanization with its outer shape, rigid and closable on both sides by a lid vulcanization, the ends each have a belonging to the vulcanization annular contour insert, the air spring blank to over its ends also encloses and also the Luftfederbalgwulst on its outside covers and supports. The lid is designed so that it can be moved during vulcanization in the direction of the air spring blank and increasingly closes the vulcanization mold.

In the vulcanization of bellows, so for example of Mehrfaltenbälgen or rolling bellows, two different methods can be applied, namely a vulcanization with bladder and a vulcanization without bladder. In vulcanization with bladder, a Luftfederbalgrohling is first in a separation and air removal solution and then mechanically preformed. Subsequently, the air spring blank is placed in a shape that surrounds it cylindrical. Thereafter, the air spring blank is pulled over a sunken bladder. The initially open on both sides ends of the outer mold are each almost closed. By pressurizing the bladder with pressure, the air spring blank is pre-buffed until it almost fills the mold. Upon reaching the predetermined air spring blank diameter, the mold automatically closes and vulcanization can begin. After completion of the vulcanization opens the mold, the bladder falls and the vulcanized air spring is removed.

During vulcanization with bladder pressure and temperature is transferred by means of superheated steam through the bladder to the air spring blank. It is easy to see that in vulcanization with bladder, the heat required to crosslink the rubber takes longer to reach the air spring blank. For this reason, the vulcanization time of the bellows-free vulcanization is shorter than that of vulcanization with bladder.

During vulcanization without bladder, the steam passes directly to the air spring blank to be vulcanized. However, bellows-free vulcanization can only be carried out with air springs with a clamping bead, because only these can be firmly anchored in the mold. For many types of air bellows, however, is not possible due to their construction. Air spring bellows are often provided at their ends with a Luftfederbalgwulst containing a core of wire or other reinforcements. The cross section of the Luftfederbalgwulstes is inside, d. H. to the air spring interior shaped conically shaped and thus forms a sealing cone with a cone-shaped opening on a complementary cone-shaped receptacle z. B. a Abrollkobens is pressed. The conical surfaces or the conical connection tapers in the direction of the air spring interior, so that with appropriate internal pressure in the air spring of the air spring bellows is further "pushed" under load on the sealing cone, so in the tendency provides itself by internal pressure self-reinforcing seal.

Such air springs are known per se and mainly in commercial vehicles, but increasingly also in trailers in use. The load of the air spring is usually a compressive load, so that the cone-clamping seat connection provides a high level of security. For such air spring bellows but the previous methods of clamping in the bellows-free vulcanization can not or hardly apply, so you have to resort to the vulcanization with bellows and must use air hoses for the production of air springs with conical sealing surfaces.

One disadvantage, of course, is that the heating hoses are wearing parts with a limited service life, in the event of failure of which defective products are produced and standstill and set-up times occur at the production facilities. The disadvantages of the poorer heat transfer during vulcanization with airbags / bladders are already mentioned above. The insertion of the heating hoses also means an extra effort in handling and possibly also requires the use of additional devices.

Various types of bellows-free vulcanizing apparatus are now known in the art. So revealed the DE 101 03 257 A1 a device for Heizschlauchlosen vulcanization of air spring roller bellows with an insertable into the air spring blanking and spreading device, which consists of an axially movable center mechanism, are provided on the two plate-shaped latch and segment systems for clamping end of the air spring blank. This device is relatively complicated and requires extensive bushings for the operation of the inner tools.

So for the invention, the object was to provide a device and method, with the air spring bellows or Luftfederbalgrohlinge / air spring blanks with cone-compression fit connection can be safely bellows vulcanized.

This object is achieved by the features of the main claim. Further advantageous embodiments are disclosed in the subclaims.

In this case, cover and contour insert of the device have complementary conical surfaces, which essentially represent an extension or continuation of the conical sealing surface of Luftfederbalgwulstes in their form and are designed so that during vulcanization, the conical sealing surface of Luftfederbalgwulstes by supporting and conditioning the Luftfederbalgwulstes in the sealing area is formed of the lid and an emerging Materialaustrieb is guided via sealing gaps in the connection region between the lid and contour insert and there received in a cavity.

• – der Kontureinsatz eine nach innen geöffnete und in Längsrichtung der Vulkanisationsform sich erstreckende konische Innenfläche aufweist, die in ihrer Form im Wesentlichen als eine Verlängerung oder Weiterführung der konischen Dichtfläche des Luftfederbalgwulstes ausgebildet ist,
• – der Deckel eine nach außen gerichtete und in Längsrichtung der Vulkanisationsform sich erstreckende konische Außenfläche aufweist, die zur konischen Dichtfläche des Luftfederbalgwustes und zur konischen Innenfläche des Kontureinsatzes im Wesentlichen komplementär ausgebildet ist,
• – wobei die konische Innenfläche des Kontureinsatzes ausgehend vom Luftfederbalgwulst und in Längsrichtung sich erstreckend drei funktional unterschiedliche Zonen aufweist, nämlich
• a) zunächst einen ersten konischen Ringflächenteil, der bei geschlossener Vulkanisationsform mit der konischen Außenfläche des jeweiligen Deckels einen Ringspalt bildet,
• b) daran nach außen anschließend, d. h. nach außen in bezug auf die Vulkanisationsform oder den Luftfederrohling, eine umlaufende Ringnut zur Aufnahme eines bei der Vulkanisation entstehenden Materialaustriebs, und
• c) an die Ringnut nach außen anschließend einen zweiten konischen Ringflächenteil, der im Zusammenwirken mit der konischen Außenfläche des jeweiligen Deckels die Vulkanisationsform bei geschlossenen Deckeln abdichtet.

Such an embodiment of the device allows the bellows-free vulcanization for air spring bellows or Luftfederbalgrorollinge with cone-compression fit connection. This is particularly advantageous in a device according to the invention the case in which

• The contour insert has an inwardly opened and in the longitudinal direction of the vulcanization mold extending conical inner surface which is formed in its shape substantially as an extension or continuation of the conical sealing surface of the Luftfederbalgwulstes
• - The cover has an outwardly directed and extending in the longitudinal direction of the vulcanization mold conical outer surface which is formed to the conical sealing surface of the Luftfederbalgwustes and the conical inner surface of the contour insert substantially complementary,
• - The conical inner surface of the contour insert from the Luftfederbalgwulst and extending in the longitudinal direction extending three functionally different zones, namely
• a) initially a first conical annular surface part, which forms an annular gap with the conical outer surface of the respective lid when the vulcanization mold is closed,
• b) thereafter outwardly, ie outwardly with respect to the vulcanization mold or the air spring blank, a circumferential annular groove for receiving a material produced during vulcanization Materialaustriebs, and
• c) to the annular groove to the outside then a second conical annular surface part which seals the vulcanization mold in closed lids in cooperation with the conical outer surface of the respective lid.

Such a division of the conical inner surface of the contour insert into three functionally different zones, wherein the inner surface of the contour insert rests against the conical outer surface of the lid, which also supports the conical sealing surface of the Luftfederbalgwulstes, allows a secure seal on the complemantärkonisch trained, but without split "functional zones" , A catching the resulting shoot and the secure geometrically correct shaping of the conical sealing surface of the air bag through vulcanization without additional clamping devices.

The conical outer surface of the lid can be divided to zones with different cone angles to improve the centering of the inserted into the form Luftfederbalgrohlings.

An advantageous development is that the circumferential annular groove is formed as an approximately semicircular cavity. This allows a simple production, for example by means of turning.

A further advantageous embodiment is that the first and second conical annular surface part different cone angle, d. H. Opening angle. Thus, the functions can direct densities, supports, shoots, fix form, be further strengthened and adapted. For example, here a double cone with sealing and product cone, d. H. with flat and steep angles can be used.

A further advantageous embodiment is that the contour insert or the lid are designed in several parts. For a more targeted temperature control is possible. Also, this can simplify the production of complicated shapes. The same applies to a further advantageous embodiment, which consists in that the contour insert or cover are formed divided over the circumference.

A particularly suitable method for actuating such a device for bellows-free vulcanization is that the pressure force applied to the cover movable during vulcanization in the direction of the air spring blank is changed depending on the flow behavior and / or the degree of crosslinking. This intensifies the effect of the individual functional surfaces or areas in a very targeted manner.

An advantageous embodiment of the method is that the pressure force on the upper and the lower lid is changed independently. This also supports the effect of the individual functional areas or areas. Advantageously, instead of the permanent force control, a time-controlled force / travel limitation can also be used. In this case, force and displacement are dependent on the temperature-dependent flow behavior or the degree of crosslinking and the shrinkage behavior derive the tissue over time. This controlled movement may be different for the upper and lower sides.

A further advantageous embodiment is that the Materialaustrieb is introduced prior to vulcanization as additional material in the region of the Luftfederbalgwulstes in the air spring blank. Thus, the "transport path" of the shoot is shortened and the process easier to carry out.

Reference to an embodiment, the invention will be explained in more detail. Show it

1 The upper part of a device according to the invention for bellows vulcanization as a sketch in section at the beginning of vulcanization

2 The upper part of a device according to the invention for bellows vulcanization as a sketch in section to the end of the vulcanization

3 a finished vulcanized LuftfederLuftfederbalg with only one side to the later air spring interior trained conical sealing surface

The 1 shows the upper part of a device according to the invention 1 for the bellow-free vulcanization of a Luftfederbalgrohlings 2 for an air suspension bellows on average. The air spring blank 2 is already at its two ends with a Luftfederbalgwulst 3 provided with an inner core wire or strength carrier. The airbag bellows 3 obtained during vulcanization seen in cross-section an inwardly directed, ie the later air spring interior trained conical sealing surface 4 by support and attachment to the complementary shaped lid. The device for bellows vulcanization is shown as a sketch in section at the beginning of vulcanization, the lid is not yet fully retracted. 2 on the other hand shows the upper part of a device according to the invention for bellows vulcanization as a sketch in section to the end of the vulcanization, the lid is fully retracted.

In the synopsis of 1 and 2 you can see the air spring blank 2 which, during vulcanization, with one defining its outer shape, rigid and on both sides by a lid 5 sealable vulcanization mold 6 surrounding is, the end each have an annular and vulcanization associated replaceable contour insert 7 has, which encloses the air spring blank beyond its ends and also the Luftfederbalgwulst 3 on its outside covers.

The lid 5 is designed so that during vulcanization in the direction of the air spring blank 2 is movable and the vulcanization mold 6 increasingly closes.

The contour insert 7 has an inwardly open and in the longitudinal direction of the vulcanization mold 6 extending conical inner surface 8th in essence, in their shape as an extension or continuation of the conical sealing surface 4 of the bellows bulge 3 is trained.

The lid 5 has an outwardly directed and in the longitudinal direction of the vulcanization mold extending conical outer surface 9 on that to the conical sealing surface 4 the Luftfederbalgwustes 3 and the conical inner surface 8th of the contour insert 7 is formed substantially complementary.

• a) zunächst einen ersten konischen Ringflächenteil 8.1, der bei geschlossener Vulkanisationsform mit der konischen Außenfläche 9 des Deckels 5 einen Ringspalt 10 bildet,
• b) daran nach außen anschließend, d. h. in bezug auf die Vulkanisationsform oder den Luftfederrohling, eine umlaufende Ringnut 8.2 zur Aufnahme eines bei der Vulkanisation entstehenden Materialaustriebs, und
• c) an die Ringnut 8.2 nach außen anschließend einen zweiten konischen Ringflächenteil 8.3, der im Zusammenwirken mit der konischen Außenfläche 9 des jeweiligen Deckels 4 die Vulkanisationsform bei geschlossenen Deckeln abdichtet.

The conical inner surface 8th of the contour insert 7 points from the Luftfederbalgwulst 3 and in the longitudinal direction extending to three functionally different zones, namely

• a) first a first conical ring surface part 8.1 in the closed vulcanization mold with the conical outer surface 9 of the lid 5 an annular gap 10 forms,
• b) then outwardly, ie with respect to the vulcanization mold or the air spring blank, a circumferential annular groove 8.2 for receiving a resulting in the vulcanization Materialaustriebs, and
• c) to the annular groove 8.2 to the outside then a second conical ring surface part 8.3 which interacts with the conical outer surface 9 of the respective lid 4 the vulcanization mold seals with closed lids.

The circumferential ring groove 8.2 is designed as an approximately semicircular cavity. The seal according to lit. c) can alternatively / additionally on the upper side of the contour insert 7 and the flange of the lid 5 respectively.

The lid designed as a forerunner 5 is permanently pressed during the vulcanization process with a certain force in the Kernwulst, ie in the direction of the air spring blank. Here, the annular gap remains 10 obtained in the form. This leaves the expulsion of the material against the force direction in the space provided for this purpose cavity / annular groove 8.2 to. The on the lid 5 applied force follows a special force profile depending on the flow behavior and / or the degree of crosslinking of the air spring bellows material. This also depends on the behavior of the air suspension bellows installed during the vulcanization process. The force can be introduced on both sides via a cone as well as each side over both cones. The material to be expressed is defined previously introduced as additional material in the sealing cone area in the air spring blank.

3 shows a fully vulcanized air spring bellows 11 with a conical sealing surface formed only on one side for the later air spring interior 4 ,

LIST OF REFERENCE NUMBERS

1

Device for bellow-free vulcanization

2

Luftfederbalgrohling, also called air spring blank

3

Luftfederbalgwulst

4

Conical sealing surface of the bellows bead

5

Closable lid of the vulcanization mold

6

vulcanization mold

7

contour insert

8th

conical inner surface of the contour insert 7

8.1

first conical ring surface part

8.2

Annular groove / cavity

8.3

second conical ring surface part

9

conical outer surface of the lid 5

10

annular gap

11

Vulcanized air bellows

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10103257 A1 [0007]

Claims (10)

Contraption ( 1 ) for the bellows-free vulcanization of an air spring blank ( 2 ), wherein the air spring blank at its two ends with a Luftfederbalgwulst ( 3 ), the inwardly directed conical sealing surfaces seen after vulcanization ( 4 ), wherein the air spring blank ( 2 ) during vulcanization with its outer shape determining, rigid and on both sides by a lid ( 5 ) sealable vulcanization mold ( 6 ) is surrounding, the end each have an annular contour insert ( 7 ), which the air spring blank ( 2 ) encloses beyond its ends and also the Luftfederbalgwulst ( 3 ) on its outside, the lid ( 5 ) is formed so that it during vulcanization in the direction of the air spring blank ( 2 ) and the vulcanization mold ( 6 ) increasingly closes, characterized in that cover ( 5 ) and contour insert ( 7 ) complementary conical surfaces ( 8th . 8.1 . 8.3 . 9 ), which in their shape substantially an extension or continuation of the resulting conical sealing surface of the Luftfederbalgwulstes ( 3 ) and are formed so that during the vulcanization, the conical sealing surface of the Luftfederbalgwulstes ( 3 ) by support and installation of the bellows bead ( 3 ) is formed in the sealing region of the lid and an emerging Materialaustrieb via sealing gaps ( 10 ) in the connection region between the lid and contour insert and there in a cavity ( 8.2 ) is recorded. Device according to claim 1, characterized in that - the contour insert ( 7 ) an inwardly open and in the longitudinal direction of the vulcanization mold ( 6 ) extending conical inner surface ( 8th ) substantially in shape as an extension or continuation of the conical sealing surface ( 4 ) of the bellows bead ( 3 ) is formed, - that the lid an outwardly and in the longitudinal direction of the vulcanization mold ( 6 ) extending conical outer surface ( 9 ) facing the conical sealing surface ( 4 ) of the bellows bead ( 3 ) and the conical inner surface ( 8th ) of the contour insert is formed substantially complementary, - wherein the conical inner surface ( 8th ) of the contour insert ( 7 ) from the Luftfederbalgwulst ( 3 ) and extending in the longitudinal direction extending three zones, namely a) first a first conical annular surface part ( 8.1 ), which is closed when the vulcanization mold ( 6 ) with the conical outer surface ( 9 ) of the respective lid forms an annular gap, b) outwardly thereupon a circumferential annular groove ( 8.2 ) for receiving a material produced during the vulcanization Materialaustriebs, and c) to the annular groove to the outside then a second conical annular surface part ( 8.3 ) in cooperation with the conical outer surface ( 9 ) of the respective lid, the vulcanization mold ( 6 ) seals with closed lids. Apparatus according to claim 2, wherein the circumferential annular groove ( 8.2 ) is formed as an approximately semicircular cavity. Apparatus according to claim 3, wherein the first and second conical annular surface portions have different cone angles (opening angles). Device according to one of the preceding claims, in which the contour insert ( 7 ) or the lid ( 5 ) are formed in several parts. Apparatus according to claim 5, wherein the contour insert ( 7 ) or lid ( 5 ) are formed divided over the circumference. Use of a device according to one of claims 1 to 6 for the production of multi-fold air bellows or Luftfederrollbälgen. Method for actuating a device for bellows-free vulcanization according to one of Claims 1 to 7, characterized in that the cover (4) which can be moved to the position during the vulcanization in the direction of the air spring blank ( 5 ) applied pressure force is changed depending on the flow behavior and / or the degree of crosslinking or a time-controlled force limit. A method according to claim 8, wherein the pressing force on the upper and lower lids is changed independently. The method of claim 8 or 9, wherein the material ejection is introduced prior to vulcanization as additional material in the region of the Luftfederbalgwulstes in the air spring blank.

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