EP2686574A1

EP2686574A1 - Pneumatic brake cylinder with a labyrinth flow duct

Info

Publication number: EP2686574A1
Application number: EP12708820.1A
Authority: EP
Inventors: Harry-Werner Kraus; Siegfried Strobel; Peter Mayer; Markus HAUZENEDER; Ibrahim DARWISH
Original assignee: Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH; Knorr Bremse Systeme fuer Schienenfahrzeuge GmbH
Current assignee: Knorr Bremse Systeme fuer Nutzfahrzeuge GmbH; Knorr Bremse Systeme fuer Schienenfahrzeuge GmbH
Priority date: 2011-03-17
Filing date: 2012-03-08
Publication date: 2014-01-22
Also published as: WO2012123316A1; CN103459878A; DE102011014261A1

Abstract

A pneumatic brake cylinder (2, 4) for brake systems of vehicles, with a brake piston (8, 26) which is arranged in the brake cylinder housing (15) and can be brought into a release or brake application position by ventilating and venting a brake chamber (12, 20), wherein the volume of at least one chamber (14, 31, 36) differing from the brake chamber (12, 20) is reduced or enlarged owing to the application or release of the brake, and a ventilation and venting opening (34) connecting the at least one chamber (14, 31, 36) to the atmosphere is provided. The at least one chamber (14, 31, 36) is connected to the ventilating and venting opening (34) by at least one labyrinth flow duct (38) which is designed in the manner of a labyrinth seal and repeatedly deflects a flow, which can be attributed to the application and/or release of the brake, from the chamber (14, 31, 36) into the atmosphere or from the atmosphere into the chamber (14, 31, 36).

Description

Pneumatic brake cylinder with labyrinth flow channel

Description of the prior art

The invention relates to a pneumatic brake cylinder for brake systems of vehicles, with a arranged in the brake cylinder housing brake piston, which can be brought by venting a brake chamber in release or Zuspannstellung, wherein the volume of at least one deviating from the brake chamber chamber due to the application or releasing the brake is reduced or enlarged and a connecting the at least one chamber with the atmosphere venting opening is provided, according to the preamble of claim 1.

Such a brake cylinder is known for example from DE 10 2007 032 966 A1. The brake cylinder is there part of a force generator, by which braking forces are applied via a brake caliper on a brake disc of a disc brake of a rail vehicle. The brake cylinder is a service brake cylinder because the service brake forces are generated by it during a service braking. It can be designed as a diaphragm cylinder or as a piston cylinder with a sealing sleeve. Furthermore, the brake cylinder may have an inserted cylinder liner or the cylinder liner may be formed directly on the inner wall of the brake cylinder housing.

To transmit the braking forces on the brake caliper is a gear, there is an eccentric, which is amplified via a hinged to the brake piston rod eccentric shaft, the piston force according to their leverage and forwarded to the caliper levers.

In the event that a parking brake or emergency brake is provided in addition to the service brake, the force generator comprises a spring brake cylinder. In this case, at least one storage spring biases a spring-loaded brake piston in the application position, wherein the spring-loaded brake piston is brought into the release position by venting a spring-loaded brake chamber in the release position and when venting. The spring brake piston rod acts on the service brake piston rod on the eccentric shaft and thus on the caliper levers of the brake caliper.

The service brake cylinder with the spring brake cylinder then forms the force generator which acts on the brake caliper via the Excentergetriebe. In general, these four modules are locked together in a brake caliper unit, as shown in DE 10 2007 032 966 A1. Such a brake caliper unit is then attached to a bogie and acts on a co-rotating with an axis brake disc.

Because air is displaced by the movements of the service brake piston, the spring-loaded piston and the eccentric shaft and it is undesirable to create an overpressure or underpressure in the housings, a ventilation of these three areas must be provided to the outside. Without such venting, for example, the back pressure would reduce the braking force. On the other hand, piston seals can prematurely wear out or be damaged.

The exchange of air with the atmosphere has the consequence that condensate can form during temperature fluctuations in the brake cylinder housing. On the one hand, this condensation can lead to corrosion and, on the other hand, to sealing problems of piston seals when the condensation on the inner wall of the brake cylinder freezes.

Furthermore, water can enter through the ventilation openings in the brake cylinder housing if, for example, the brake caliper unit is arranged in a region loaded by spray water, in particular in the region of wheel brake disks. Not least, when cleaning the brake caliper unit in the bogie with a high-pressure cleaner penetrate water in the brake caliper unit, which has a particularly strong corrosive effect because of the most aggressive cleaning agents used. The present invention is based on the object to further develop a brake cylinder of the type mentioned above, on the one hand, a pressure equalization with the atmosphere is made possible, and on the other hand, a sufficient protection against ingress of water and dirt is ensured. This object is achieved by the features of claim 1.

Disclosure of the invention

The invention provides that the at least one chamber with the ventilation opening by at least one formed in the manner of a labyrinth seal, a attributable to the application and / or release of the brake flow from the chamber into the atmosphere or from the atmosphere connected to the chamber several times redirecting labyrinth flow channel.

A brake chamber is to be understood as meaning a chamber whose ventilation or venting via the brake piston ultimately causes the brake to be applied or released. By contrast, a deviating from the brake chamber chamber is to be understood a chamber in which when releasing or applying the brake only a displacement of air volume takes place, but which does not directly serve for applying the braking force or brake release force. Such a chamber deviating from the brake chamber may, in particular, also be a chamber of a brake transmission directly installed with the brake cylinder, because air displacements may also occur in the interior of such a brake mechanism upon release or application of the brake. In the case of a gap or labyrinth seal, throttling effects occur due to the multiple deflections (for example by 90 degrees) relative to the flow direction, as a result of which pressure energy and flow velocity are lost. This reduces the tendency for water droplets to be sucked from the outside by piston movements.

Because of the labyrinth flow channel, there is still less danger that water will enter when cleaning with high-pressure cleaners. Because the multiple deflections of the labyrinth flow channel form a kind of protective seal for the interior of the brake cylinder housing.

In principle, such a brake cylinder can be any type of pneumatic brake cylinder in which piston movements result in a displacement of air volume in at least one chamber deviating from the brake chamber, ie, for example, an active pneumatic service brake cylinder, in which a Return spring is arranged to bias the brake piston in the release position. Furthermore, it may also be a passive pneumatic spring accumulator brake cylinder, in which the braking forces are applied by at least one acting on a spring brake piston storage spring and in which it also comes in a memory spring containing chamber by piston movements to a displacement of air volume. Furthermore, it can also be a combined service brake and spring brake cylinder, in which the two above-mentioned chambers are connected via the labyrinth flow channel with the ventilation opening. Last but not least, the brake cylinder, in particular a combined service brake and spring brake cylinder can be locked with a transmission to form a unit, in particular in a common housing, wherein it can also come in the interior of the transmission when applying or when releasing the brake to displacement of air volume. It is also advantageous to arrange an inside of the gearbox te chamber connected via the labyrinth flow channel with the ventilation opening. Thus, with a single labyrinth flow channel or with a single ventilation opening several chambers can be vented and kept largely free from contamination and moisture.

The measures listed in the dependent claims advantageous refinements and improvements of the invention specified in the independent claims are possible.

Particularly preferably, the ventilation opening in the use position of the brake cylinder is arranged in the lowermost region of the brake cylinder housing. As a result, condensate water caused by atmospheric moisture collects in this lowermost region and can drain out of the brake cylinder housing or can be blown out by the air flow resulting from piston movements. This is supported by operating vibrations of the vehicle.

For the same purpose, the labyrinth flow channel seen in the operating position of the brake cylinder from its end facing away from the atmosphere to its end facing the atmosphere preferably on a slope.

According to a preferred embodiment, the labyrinth flow channel is formed in an insert inserted into a ventilation bore of the brake cylinder housing. For example, the vent hole is a threaded hole and the insert is formed by a male screw. This screw is preferably made of plastic, wherein in the screw then at least part of the labyrinth flow channel is formed.

In this case, the flow-deflecting labyrinth flow channel can have at least one axial section, one section extending in the circumferential direction relative to the axial direction of the ventilation bore and at least include a radial section. To implement the insert can have a cup-shaped sleeve with a head side radially superior head portion, wherein between a radially outer peripheral surface of a central axial and associated with the chamber sleeve blind hole sleeve wall and a radially inner wall of the ventilation hole through the Head to the atmosphere and are formed by the radially outer sleeve wall radially outwardly extending ribs with each other in the circumferential direction limited part ring spaces, of which only some Teilringräume axial openings in the head part with the atmosphere and the other part annuli by means formed in the sleeve wall radial openings are in flow communication with the central sleeve blind hole, wherein the partial annular spaces each by a formed between a rib and the radially inner wall of the ventilation hole and gap with each other communicate.

Then, in the at least one chamber displaced air is first pressed into the sleeve blind hole and from there through the radial openings in the sleeve wall in the other part ring spaces. From there, the air passes through the gap provided between the partial annular spaces for communication in the one part annular spaces, which now blow the air into the atmosphere by means of the axial openings in the head part. Thus, the air undergoes repeated flow deflections, which promotes the separation of particles entrained in the air.

In addition, at least one particle filter may be held in the labyrinth flow channel, in particular in the central axial blind pocket bore, for example in the form of a dust filter or sand filter, in order to prevent the penetration of dirt particles into the brake cylinder housing.

Particularly preferably, the brake cylinder is a service brake cylinder, in which in the chamber, a brake piston in the release position biasing return spring is arranged. This service brake cylinder may preferably form a structural unit with a transmission, in particular with an eccentric transmission whose transmission input interacts with the brake piston rod and its transmission output with the brake mechanism. In particular, in the interior of the eccentric drive an eccentric shaft is arranged, which acts on a brake caliper, wherein the brake piston rod is articulated on the eccentric shaft. Then, for example, an interior of the transmission by means of at least one flow channel with the remote from the atmosphere end of the labyrinth flow channel and the vent hole in flow communication. Thus, a single vent hole and the trained in her labyrinth flow channel is provided for both a ventilation of the at least one chamber of the brake cylinder and the interior of the transmission, resulting in a reduced construction cost.

In this case, may be attached to an outer peripheral surface of the brake piston rod, a radial inner edge of a rolling bellows whose radially outer edge is fixed to a through hole of the brake cylinder for the brake piston rod to seal the chamber of the brake cylinder relative to the interior of the transmission. As a result, the tendency is reduced that penetrate into the brake cylinder housing humidity in the interior of the transmission and can condense there, which is advantageous because transmission parts are particularly susceptible to corrosion.

Particularly preferably, furthermore, the brake cylinder with a spring-loaded brake cylinder can form a constructional unit which includes a spring brake piston with a spring brake piston rod which is arranged in a spring brake cylinder housing and can be actuated by at least one storage spring, which piston passes through a central bore of an intermediate wall between the brake cylinder and the spring brake cylinder protrudes so that it acts on the brake piston, wherein the spring brake piston includes a spring-containing spring chamber of a loading and ventable spring brake chamber of the spring brake cylinder separates. Upon actuation of the spring brake piston, there is a displacement or suction of air from or into the spring chamber, which is why this also has to be vented or vented.

For this purpose, the spring chamber of the spring brake cylinder, for example by means of at least one flow channel with the remote from the atmosphere end of the labyrinth flow channel in flow communication. Then, the ventilation of the spring chamber by the same, in particular formed on the brake cylinder housing ventilation opening, through which also the return spring receiving chamber of the service brake cylinder and the interior of the transmission is vented.

The spring-loaded cylinder, the service brake cylinder and the transmission are preferably locked together, in particular, the spring brake cylinder, the service brake cylinder and the transmission on a common housing, wherein the spring chamber of the spring brake cylinder, the return spring housed chamber of the service brake cylinder and the interior of the transmission via a single and common ventilation and vent and a labyrinth flow channel can be ventilated and vented. It is also conceivable, however, any pairwise combinations of service brake cylinder, spring brake cylinder and gearbox with common vent hole and labyrinth flow channel.

If the brake cylinder therefore has several chambers affected by air displacement or exhaust effects, as is the case, for example, with combined service brake and spring brake cylinders with and without a blocked transmission, at least two chambers can communicate with one another and with one another by means of at least one flow channel the atmosphere facing away from the labyrinth flow channel are in flow communication. In the sense of an advantageous additional function can then next the ventilation of the chambers take place by means of the flow channel and a pressure equalization between the chambers.

The spring chamber of the spring brake cylinder with the end remote from the atmosphere of the labyrinth flow channel in connection flow channel is preferably formed by at least one covered by a cover to the atmosphere groove in the brake cylinder housing. This cover is preferably made of plastic and is held in the groove, for example, frictionally and / or positively, in particular there clipped. Such a solution is very cost effective.

According to a further embodiment, the labyrinth flow channel can have a plurality of successively arranged and alternately oppositely arcuate formed Aussackungen. As a result, the air flow is directed to a circular arc-shaped path and exposed to centrifugal forces through which entrained in the air flow particles or moisture droplets can settle due to the higher density in the Aussackungen.

According to a development of the labyrinth flow channel and the ventilation opening are formed in an insert inserted from the outside into an outer recess of the brake cylinder housing. Developing this recess is connected to at least two air displacements during release or braking exposed chambers and trained in use labyrinth flow channel connects the at least two chambers with each other and this with the ventilation opening. Thus, the use fulfills a multiple function by allowing on the one hand a certain pressure equalization between the chambers affected by air displacement effects and on the other each creates a connection between the chambers and the ventilation opening by means of the trained in it labyrinth flow channel, which also the air flow with throttles the effects already described above. According to a development, it can also be provided that the labyrinth flow channel is provided at its end facing the atmosphere with a splash guard with undercut cross section. Due to this, it is largely prevented that spray water can penetrate from the outside into the labyrinth flow channel, which is advantageous especially in the case of brake cylinders exposed to environmental influences.

More specifically, it will be apparent from the following description of embodiments.

drawing

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description. In the drawing shows

1 shows a cross-sectional view of a brake caliper unit with a

Brake cylinder according to a preferred embodiment of the invention;

2 shows a cross-sectional view of the brake cylinder together with the transmission of

Fig.1;

A single representation of an insert of the brake cylinder of

Fig.1;

Figure 4 is a perspective view and a cross-sectional view of the insert of Figure 3;

5 shows a cross-sectional view of the insert of Figure 3 according to another embodiment.

6 shows a plan view of a brake cylinder housing of the brake cylinder of Figure 1 with a flow channel in an exploded view.

7 shows the flow channel of Figure 6 in cross section.

8 shows a cover for the flow channel of Figure 6; 9 is a cross-sectional view of another embodiment of a brake cylinder including gear;

10 is a cross-sectional view of an enlarged section of the

Brake cylinder of Figure 9 with an insert;

1 is a perspective view of the enlarged detail of

Brake cylinder of Figure 9 with the insert;

12 is a plan view of the use of Fig.10 and Fig.1. 1 Description of the embodiments

In Figure 1, a service brake cylinder 2 is part of a force generator 1, by which braking forces are applied via an Excentergetriebe 3 and a brake caliper 5 on a brake disc not shown there disc brake of a rail vehicle. The service brake cylinder 2 is preferably designed as a diaphragm cylinder, alternatively it could also be a piston cylinder.

For transmitting the braking forces of a service brake piston rod or push rod 28 to the Excentergetriebe 3 this is hinged to an eccentric shaft 7, whereby the piston force is amplified according to the lever ratio and the caliper lever 9, the caliper 5 is forwarded. This principle is described in detail in DE 10 2007 032 966 A1, so it will not be discussed further here.

In addition to the service brake here is a parking or emergency brake is provided. Then the force generator 1 in addition to the service brake cylinder 2 and the Excentergetriebe 3 also includes a spring brake cylinder 4. The service brake cylinder 2 and the spring brake cylinder 4 then act on the Excentergetriebe 3 on the brake caliper 5 to operate them.

Here are the four modules - spring brake cylinder 4, service brake cylinder 2, Excentergetriebe 3 as a force generator 1 on the one hand and the brake caliper 5 with the caliper levers 9 on the other hand preferably in one Brake caliper unit 1 1 blocked each other. This brake caliper unit 1 1 is attached to a bogie of the rail vehicle and acts on the end arranged on the brake calipers 5 brake pads 13 on a co-rotating with an axis brake disc.

2, the power generator 1 is shown in longitudinal cross section, wherein the service brake cylinder 2, the eccentric 3 and the structurally and functionally connected spring brake cylinder 4 preferably have a common brake cylinder housing 15.

The service brake cylinder 2 and the spring brake cylinder 4 are separated by an intermediate wall 6 from each other. Within the spring brake cylinder 4, a spring brake piston 8 is slidably disposed, wherein on one side of the spring brake piston 8, a storage spring 10 is present. The accumulator spring 10 is supported on its opposite side at the bottom of the spring brake cylinder 4. Between the spring brake piston 8 and the intermediate wall 6, a spring brake chamber 12 is formed, which is aerated and released for releasing and applying the parking brake. When venting the spring brake chamber 12 of the spring brake piston 8 is moved under tension of the accumulator spring 10 axially in the release position of the parking brake. During this displacement of the spring brake piston 8, the air which is present within the spring chamber 14 receiving the accumulator spring 10, compressed and passes through a later explained in more detail ventilation and vent hole 34 into the atmosphere. If, however, the spring brake chamber 12 is vented for the purpose of braking, then the memory spring 10 can move the spring brake piston 8 in Zuspannstellung.

The spring brake piston 8 is connected to a Federspeicherbremskolbenstan- ge 18, which extends through the intermediate wall 6 in a service brake chamber 20 of the service brake cylinder 2. A seal assembly 22 inserted into a central bore 21 of the intermediate wall 6 seals relative to the spring brake piston rod 18 during its longitudinal movement. In the service brake chamber 20 opens a not shown inlet, via which for actuating the service brake cylinder 2 compressed air is introduced into a service brake chamber 20 and drained. The compressed air acts on a within the service brake cylinder 2 axially displaceable service brake piston 26, which is sealed relative to a guide surface of the service brake cylinder 2 by means of a seal 24. More specifically, the service brake piston 26 separates the pressure brake-loaded and unloaded service brake chamber 20 of the service brake cylinder 2 from a spring brake chamber 30 supported on the service brake piston 26 receiving spring chamber 31st Instead of a service brake piston 26 and an elastic membrane could be provided.

The service brake piston 26 is connected to the push rod 28, which is articulated to the eccentric shaft 7 of the Excentergetriebes 3. The service brake cylinder 2 is an active brake cylinder, i. that the service brake is applied by venting the service brake chamber 20 and released by venting. The on the one hand on the service brake piston 26 and on the other hand at the bottom of the service brake cylinder 2 supporting return spring 30 ensures that the push rod 28 is retrieved at vented service brake chamber 20 in the release position. The spring brake piston rod 18 is supported in a central opening of the push rod 28 of the service brake cylinder 2, so that the spring brake piston rod 18 can act on the eccentric shaft 7 and thus also on the caliper lever 9 of the brake caliper 5 via the push rod 28.

Not least is attached to an outer peripheral surface of the push rod 28 of the service brake cylinder 2, a radial inner edge of a rolling bellows 35, the radially outer edge is attached to a through hole of the service brake cylinder 2 to the transmission housing 17 toward the spring chamber 31 against the interior 36 of the Excentergetriebes 3 seal. As already indicated above, the force generator 1 consisting of the spring brake cylinder 4, the service brake cylinder 2 and the eccentric gear 3 has preferably only the spring chamber 14 of the spring-loaded brake cylinder 4, the spring chamber 31 of the service brake cylinder 2 and preferably also an inner or eccentric shaft space 36 the brake cylinder housing 15 with the atmosphere connecting vent hole 34.

In the formed for example in the brake cylinder housing ventilation hole 34 is formed in the manner of a labyrinth, attributable to the application and / or release of the brake flow from the spring chambers 14, 31 and from the interior 36 of the Excentergetriebes 3 in the atmosphere or formed from the atmosphere in the spring chambers 14, 31 and in the interior 36 of the Excentergetriebes 3 deflecting labyrinth flow channel 38, whose course is indicated in Figure 3 in dashed line. In particular, the labyrinth flow channel 38 directs the flow of air from the spring chambers 14, 31 or from the interior 36 of the transmission housing 17 into the atmosphere or the flow from the atmosphere in spring chambers 14, 31 or from the interior 36 of the transmission housing 17 several times in relation to direction around.

As is apparent from Fig.2, the ventilation hole 34 is arranged in the operating position of the service brake cylinder 2 and the power generator 1 in the lowermost region of the brake cylinder housing 15. In particular, the ventilation hole 34 may be formed in a region of the brake cylinder housing 15 that is particularly bulged down, for example.

The labyrinth flow channel 38 is formed, for example, in an insert 40 inserted into the ventilation hole 34. This insert 40 is preferably formed by a plastic screw which can be screwed into the ventilation hole 34. But for the screw 40 is also any other material conceivable, for. B. also a metal. On the other hand, the insert 40 may be held in other ways in the ventilation hole 34, for example by pressing.

As is apparent from Figure 3 to Figure 5, the screw 40 has a cup-shaped sleeve 42 having a sleeve 42 on the head radially projecting head portion 44, wherein between a radially outer peripheral surface of a central axial and with the spring chambers 14, 31 and the inner space 36 of the eccentric drive 3 connected sleeve blind hole 46 enclosing sleeve wall 48 and a radially inner wall of a cap 43 through the head portion 44 to the atmosphere and by the sleeve wall 48 radially outwardly extending ribs 50 with each other in the circumferential direction limited part ring spaces 52 are formed.

Of these partial annular spaces 52, only a few partial annular spaces 52, seen in the circumferential direction preferably each second partial annular space 52, through axial openings 54 in the head portion 44 with the atmosphere and the other (remaining) Teilringräume 52 formed in the sleeve wall 48 radial openings 56 with the central sleeves Blind hole 46 in fluid communication. The partial annular spaces 52 can each communicate with one another by a gap 58 formed between a rib 50 and the radially inner wall of the protective cap 43, as is easily imaginable with reference to FIGS. 3 and 4. There are therefore partial annular spaces 52 which are connected by means of axial openings 54 in the head part 44 with the atmosphere and partial annular spaces 52, which by means of radial openings 56 with the spring chambers 14, 31 of the brake cylinder 2, 4 and with the interior 36 of the Excentergetriebes 3 in Connection stand.

The protective cap 43 is formed, for example, cup-shaped and placed on the sleeve 42. Missing in the insert 40, the column 58 may also be formed directly between the radially inner wall of the ventilation hole 34 and the ribs 50. Then, for example, in the spring chambers 14, 31 of axial movements of the brake piston 8, 26 or in the interior 36 of the Excentergetriebes 3 displaced by a rotation of the eccentric shaft 7 air first in the sleeve blind hole 46 and from there through the radial openings 56th pressed in the sleeve wall 48 in some of the partial annular spaces 52. From there, the compressed air passes through the column 58 provided between the partial annular spaces 52 for communication into further partial annular spaces 52 and from there by means of the axial openings 54 in the head part 44 into the atmosphere. Thus, the displaced air undergoes multiple flow redirections along labyrinth flow channel 38 formed in the screw or insert 40.

As shown in FIG. 5, at least one particulate filter 60 can be held in the labyrinth flow channel 38 in addition, in particular in the central axial blind blind hole 46 of the screw 40, for example in the form of a dust or sand filter to prevent dirt particles from entering the brake cylinder housing 15 prevent.

In the exemplary embodiment shown in FIG. 2, the spring chamber 31 of the service brake cylinder 2 is in fluid communication, for example via a flow channel 62 formed in the wall of the brake cylinder housing 15 with the end of the labyrinth flow channel 38 or the insert 40 facing away from the atmosphere.

Furthermore, the spring chamber 14 of the spring brake cylinder 4, for example by means of a preferably formed in a wall of the brake cylinder housing 15 flow channel 64 with the remote from the atmosphere end of the labyrinth flow channel 38 and the insert 40 in flow communication.

Finally, the interior 36 of the Excentergetriebes 3 by means of a preferably formed in a wall of the brake cylinder housing 15 flow channel 66 with the remote from the atmosphere end of the labyrinth flow channel 38 and the insert 40 is connected. This stream Flow channel 66 is continued by the subsequent flow channel 62 in the wall of the brake cylinder housing 15, which the spring chamber 31 of the service brake cylinder 2 via the ventilation hole 34 and vented.

Then, the ventilation of the spring chamber 14 of the spring brake cylinder 4 takes place through the same ventilation opening 34 in the brake cylinder housing 15, through which the spring chamber 31 of the service brake cylinder 2 and the interior 36 of the Excentergetriebes 3 is vented and vented.

As is shown in FIGS. 6 to 8, the flow chamber 64 connecting the spring chamber 14 of the spring-loaded brake cylinder 4 with the end of the labyrinth flow channel 38 facing away from the atmosphere is preferably provided by at least one groove covered by a cover 68 toward the atmosphere 70 formed in the brake cylinder housing 15.

This cover 68 is preferably made of plastic and is held in the groove 70, for example, friction and / or positive fit and is preferably clipped into this. The cover 68 preferably has, on its surface facing towards the groove 70, a rib 72 which extends around the aperture 74 and which is inserted into the groove and defines the flow path within the flow channel 64. Through the opening 74 of the flow channel 64 is then connected to the remote from the atmosphere end of the labyrinth flow channel 38 and the insert 40.

In the embodiment shown in FIGS. 9 to 12, identical or functionally identical components and assemblies are identified with the same reference numbers in relation to the exemplary embodiment described above.

As is apparent from FIG. 10, the brake cylinder housing 15, which houses the service brake cylinder 2, the spring brake cylinder 4, and the extender transmission 3, has an outer, groove-like configuration in its lowermost region. receiving 76 which, for example, via corresponding openings 78, 80 with the return spring 30 receiving spring chamber 31 of the service brake cylinder 2, with the spring chamber 14 of the spring brake cylinder 4 and the interior or Exenterwellenraum 36 of the Excentergetriebes 3 is connected. In Fig.10 two of these openings 78, 80 are shown, wherein the one, in Fig.10 right opening 78, for example, with the spring chamber 14 of the spring brake cylinder 4 and left in Fig.10 opening 80, for example, with the spring chamber 31 of the service brake cylinder 2 and is connected to the Excenterwellenraum 36 of the Excentergetriebes 3 each for ventilation. In particular, the opening 80 is connected to the channel 66 in the brake cylinder housing 9, which leads into the interior 36 of the Excentergetriebes 3.

In this embodiment, the labyrinth flow channel 38 and the ventilation opening 34 are formed in an insert 82 inserted from the outside into the recess 76 of the brake cylinder housing 15. In this case, the labyrinth flow channel 38 formed in the insert 82 made of plastic, for example, connects the two openings 78, 80 and thus three chambers 14, 31, 36 mentioned above with one another and with the ventilation opening 34. In other words, the labyrinth discharges - Flow channel 38 on the one hand in the openings 78, 80 and on the other hand in the ventilation opening 34th

As is apparent from Figure 12, the labyrinth flow channel 38 a plurality of successively arranged and alternately counter-arcuate trained Aussackungen 84, which are integrally formed in the insert 82. In other words, in the labyrinth flow channel 38, sections bent to the right alternate with sections bent to the left.

In particular, two parallel partial labyrinth flow channels 38 a, 38 b and 38 c, 38 d are provided starting from the openings 78, 80 in the insert 82, which openings 78, 80 with the ventilation opening 34 connect. Then the air flow symbolized in FIG. 12 by arrows, for example from the atmosphere via the ventilation opening 34, the labyrinth flow channel 38 and the opening 78 into the spring chamber 14 of the spring-loaded brake cylinder 4, is directed onto a circular arc-like path and centrifugal forces exposed, through which entrained in the air flow particles or moisture droplets can settle in the Aussackungen 84 due to the higher density, as also indicated in Figure 12. These protuberances 84 can be formed directly in the right and left curved portions of the labyrinth flow channel 38 or by worm-shaped recesses.

As shown in FIG. 10 and FIG. 1, the ventilation opening 34 is formed centrally on the plate-shaped insert 82 and connected to all four partial labyrinth flow channels 38a, 38b and 38c, 38d. At its atmospheric end, i. Here in the region of the ventilation opening 34, the labyrinth flow channel 38 preferably has a splash protection device 86, for example in the form of a bell-shaped element 88 which widens outwards or towards the atmosphere and which is provided with a sleeve-shaped deflector 90 for use. In this way, a kind of undercut cross-section, which largely prevents splash water can penetrate from the outside into the labyrinth flow channel 38. The ventilation opening 34 then essentially consists of an annular gap between the bell-shaped element 88 and the deflector 90, this annular gap being in flow communication with the four partial labyrinth flow channels 38a, 38b and 38c, 38d.

As can best be seen with reference to FIG. 10, the labyrinth flow channel 38 or the four partial labyrinth flow channels 38 a, 38 b and 38 c, 38 d, viewed in the position of use of the force generator 1, from its end facing away from the atmosphere the atmosphere end facing ie from the openings 78, 80 to the ventilation opening 34 a Gradient on. The preferably one-piece, designed as a plastic injection mold ling insert is fixed for example by means of screws in the recess 76 of the Bermszylindergehäuses 15, as can be seen in particular from Fig.1 1. The attachment in the recess 76 at the same time the flow connections between the openings 78, 80 of the brake cylinder housing 15 and the labyrinth flow channel 38 and the four part labyrinth flow channels 38a, 38b and 38c, 38d produced.

Description of supply list of power generators

Service brake cylinder

Excentergetriebe

Spring brake cylinder

caliper

partition

eccentric shaft

caliper lever

Spring brake piston

storage spring

Brake caliper unit

Spring brake chamber brake pads

spring chamber

Brake cylinder housing

Spring brake piston rod Service brake chamber

drilling

sealing arrangement

poetry

Service brake piston

pushrod

return spring spring chamber

Ventilation bore interior

Labyrinth flow channel insert

shell

protective cap

headboard

Blind hole

sleeve wall

ribs

Part annular spaces

axial openings radial openings

gap

particulate Filter

flow channel

cover

groove

rib

opening

recess opening

opening

commitment

Aussackung

Splash guard bell-shaped element deflector

Claims

claims

1 . Pneumatic brake cylinder (2, 4) for brake systems of vehicles, with a in the brake cylinder housing (15) arranged brake piston (8, 26), which can be brought by venting a brake chamber (12, 20) in release or Zuspannstellung, wherein the volume of at least one of the brake chamber (12, 20) deviating chamber (14, 31, 36) reduced or enlarged due to the application or release of the brake and the at least one chamber (14, 31, 36) connected to the atmosphere and vent opening (34) is provided, characterized in that the at least one chamber (14, 31, 36) with the ventilation opening (34) formed by at least one labyrinth seal, one on the clamping and / or Loosening the brake return flow from the chamber (14, 31, 36) into the atmosphere or from the atmosphere into the chamber (14, 31, 36) is repeatedly connected diverting labyrinth flow channel (38).

2. Brake cylinder according to claim 1, characterized in that the ventilation opening (34) in the operating position of the brake cylinder (2, 4) seen in the lowermost region of the brake cylinder housing (15) is arranged.

3. Brake cylinder according to claim 1 or 2, characterized in that the labyrinth flow channel (38) in the use position of the brake cylinder (2, 4) seen from its end facing away from the atmosphere to its end facing the atmosphere (34) has a gradient.

4. Brake cylinder according to one of the preceding claims, characterized in that the labyrinth flow channel (38) in an in a ventilation hole (34) of the brake cylinder housing (15) inserted insert (40) is formed.

5. Brake cylinder according to claim 4, characterized in that the ventilation hole (34) is a threaded bore and the insert (40) is formed by a screw with external thread.

6. Brake cylinder according to claim 5, characterized in that the flow several times deflecting labyrinth flow channel (38) relative to the axial direction of the ventilation hole (34) at least one axial portion (46, 54), one in the circumferential direction extending portion (52, 58) and at least one radial portion (56).

7. Brake cylinder according to claim 6, characterized in that the insert (40) has a cup-shaped sleeve (42) with a sleeve (42) head-radially projecting head portion (44), wherein between a radially outer peripheral surface of a central axial and with the chamber (14, 31) connected to the blind hole blind bore (46) enclosing sleeve wall (48) and a radially inner wall of the ventilation hole (34) or protective cap (43) through the head part (44) to the atmosphere through and from the radially outer sleeve wall (48) radially outwardly extending ribs (50) are formed circumferentially limited partial annular spaces (52), of which only some Teilringräume (52) through axial openings (54) in the head part (44) with the atmosphere and the other partial annular spaces (52) are in fluid communication with the central sleeve blind bore (46) by means of radial openings (56) formed in the sleeve wall (48), wobe i the partial annular spaces (52) in each case by a between a rib (50) and the radially inner wall the ventilation and vent hole (34) formed gap (58) communicate with each other.

8. Brake cylinder according to one of the preceding claims, characterized in that at least two chambers (14, 31, 36) by means of at least one flow channel (62, 64, 66) with each other and with the end remote from the atmosphere of the labyrinth flow channel (38). is in flow communication.

9. Brake cylinder according to claim 8, characterized in that at least one part of the flow channel (64) by at least one by a cover (68) to the atmosphere covered outer recess (70) in the brake cylinder housing (15) is formed.

10. Brake cylinder according to claim 9, characterized in that the

Cover (68) made of a plastic and in the recess (70) is held positively and / or frictionally engaged.

1 1. Brake cylinder according to one of claims 1 to 3, characterized in that the labyrinth flow channel (38) has a plurality of successively arranged and alternately oppositely arcuate formed Aussackungen (84).

12. Brake cylinder according to claim 1 1, characterized in that the labyrinth flow channel (38) and the ventilation opening

(34) are formed in an insert (82) inserted from the outside into an outer recess (76) of the brake cylinder housing (15).

13. Brake cylinder according to claim 12, characterized in that the recess (76) with at least two chambers (14, 31, 36) connected is the and in use (82) trained labyrinth flow channel (38) the at least two chambers (14, 31, 36) with each other and this with the ventilation opening (34) connects.

14. Brake cylinder according to one of the preceding claims, characterized in that the labyrinth flow channel (38) is provided at its end facing the atmosphere (34) with a splash guard (86) with undercut cross-section.

15. Brake cylinder according to one of the preceding claims, characterized in that in the labyrinth flow channel (38) at least one particle filter (60) is arranged.

16. Brake cylinder according to one of the preceding claims, characterized in that it includes a service brake cylinder (2), wherein a chamber (31) receives a brake piston (26) in the release position biasing return spring (30).

17. Brake cylinder according to one of the preceding claims, characterized in that it includes a spring brake cylinder (4), wherein a chamber (14) at least one of the spring brake piston (8) actuated accumulator spring (10) receives.

18. Brake cylinder according to claim 16 and 17, characterized in that it is a combined service brake and spring brake cylinder (2, 4).

19. Brake cylinder according to one of the preceding claims, characterized in that it forms a structural unit with a transmission (3) whose transmission input with a brake piston rod (18, 28) of the Brake piston (8, 26) and the transmission output with a brake mechanism (5) cooperates.

20. Brake cylinder according to claim 19, characterized in that a chamber (36) through an interior of the transmission (3) is formed.

21. Brake cylinder according to claim 20, characterized in that the gear (3) as Excentergetriebe with an interior (36) arranged eccentric shaft (7) is formed, which acts on a brake caliper (5), wherein the brake piston rod (28) on the eccentric shaft ( 7) is articulated.

22, service brake cylinder according to claim 21, characterized in that on an outer peripheral surface of the brake piston rod (28), a radial inner edge of a rolling bellows (35) is fixed, whose radially outer edge is fixed to a through hole of the brake cylinder (2) to the chamber (31) with respect to the interior (36) of the transmission (3) to seal.