Patent Application
20240060487
The disclosure relates to a piston as and to a compressor, in particular an air compressor. The disclosure also relates to a compressed-air supply system, a vehicle and a method for operating a compressed-air supply system.
Compressors, in particular piston compressors in vehicles of all kinds, are widely known. They are used to provide compressed air and cover many areas of application, including brake systems, air spring systems, in particular for level control, clutch boosters and many more. Among the important target criteria in the configuration of compressors are the highest possible delivery rate, the lowest possible noise generation, the smallest possible dimensions, a low outlay on production and a high degree of robustness.
US 2015/0209986 discloses a production method for a piston having a circumferential seal in the form of a circular cup seal, in particular for use in a reciprocating piston compressor.
DE 10 2011 121 750 A1 discloses, for example, a compressor, having a piston, the piston head of which is rigidly connected to a connecting rod, wherein a connecting rod bearing eye of the connecting rod is rotatably supported on an eccentric pin of a drive shaft of a drive motor.
Nevertheless, the approach including the rigid connection between the connecting rod and the piston leads to leaks between the piston and the cylinder due to the wobbling movement inherent in the configuration, leaks which are supposed to be counteracted by appropriate configuration measures, for example, seals.
DE 10 2013 101 110 A1 discloses a reciprocating piston compressor having a piston which is driven by a slider-crank mechanism and can be moved back and forth in a cylinder and is sealed with respect to the cylinder wall, which piston is arranged in a fixed manner with respect to the connecting rod axis, wherein the piston and/or the cylinder are configured in such a way that the crescent-shaped gaps between the piston edge and the cylinder wall which arise during the compression stroke as a result of the relative inclination or tilting between the piston and the cylinder can be sealed, thereby compensating for leaks.
The concept of a two-stage compressor in which the air fed in is first compressed to a low-pressure level in a low-pressure stage and then to a high-pressure level in a high-pressure stage connected to the low-pressure stage has proven successful.
To increase compactness, a two-stage compressor can be embodied in such a way that both compressor stages are formed by just one piston, for example via a piston which can be acted upon from two sides.
GB 241,907, for example, discloses a multi-stage compressor which can implement an arbitrary number of compressor stages via a piston having an arbitrary number of stage sections and a cylinder of matching configuration.
DE 10 2010 054 710 A1 furthermore discloses a compressor for a compressed-air feed of a compressed-air supply system, which compressor has at least one two-stage compressor unit having a single cylinder with a single piston that can be acted upon from two sides in a compression volume of the cylinder.
DE 10 2012 223 114 A1 furthermore describes a double piston compressor unit. A drive shaft of the motor of the compressor unit cooperates with the unit via a slotted-link guide in the double piston of the unit in such a way that the double piston alternately carries out a compression process in the two cylinders of the unit. In this case, the axis of the drive shaft is arranged eccentrically with respect to the central axis of the two cylinders, resulting in fewer changes in the position of the piston and thus less noise generation.
The concept is still in need of improvement with regard to the abovementioned disadvantages and target criteria. It is therefore desirable to implement the function of a high-performance, in particular two-stage, compressor in a configuration that is as compact and robust as possible.
The compressor 100 of WO 2018/197182 A2 (corresponding to US 2020/0102947), already described here in this application with reference to
The compressor 100 of WO 2018/197182 A2 has:
The seal 138 on the piston 1112 already described in this application with reference to
It is an object of the disclosure to provide an improved device, in particular a piston and a compressor, as well as a method which at least partially meets the objectives and target criteria formulated above, in particular via an improved structural configuration. In particular, it is an object of the disclosure to configure the device and the method in such a way that, in the context of the improved structural configuration, on the one hand an improved sealing effect and, on the other hand, improved retention of the seal are achieved, the seal furthermore being held in a pressure-tight manner on the stepped side, thus ensuring that the first compression volume and the second compression volume are sealed, even under long-term and high stress, in the context of the wobbling movement of a piston.
The object with respect to the device is, for example, achieved via a piston according to the disclosure.
A piston according to the disclosure starts from a piston for a compressor. Such a compressor has proven successful, in particular, for a compressed-air feed of a compressed-air supply system, for operating a pneumatic system, wherein the piston is configured to be movably guided in a cylinder of the compressor during operation of the compressor and can be attached to a drive via a connecting rod, wherein the connecting rod can be connected to the piston on a piston side and can be connected to a rotating part of the drive in a rotatable manner on a drive side.
According to the disclosure, such a piston has:
In the case of such a piston, the disclosure furthermore envisages that the first compression volume and the second compression volume are connected to one another via a connecting line, which can be subjected to pressure.
In order to achieve the object, it is furthermore envisaged according to the disclosure that
The object relating to the device is, for example, also achieved by a compressor that uses the piston according to the disclosure, namely a compressor, in particular an air compressor, for a compressed-air feed of a compressed-air supply system, for operating a pneumatic system, having a first compression volume, a second compression volume, an air feed connection and a compressed-air outlet, and the piston.
According to the disclosure, the compressor is provided with:
The disclosure proceeds from the consideration that the basic approach of a piston as described in the context of the compressor of WO 2018/197182 A2 with an already advantageous seal basically provides the correct approach for the implementation of a compressor advantageously provided with a first and second compression volume. That is, that the approach is to provide a seal that seals the first compression volume with respect to the second compression volume, wherein the piston has a first end side in the form of a full side and a second end side in the form of a stepped side.
The seal is advantageously configured to seal the second compression volume with respect to a crankcase interior and/or with respect to the environment and/or to seal the first compression volume with respect to the second compression volume. The at least one seal advantageously produces a radially acting pressure-tight seal on the stepped side of the piston, both on an outer side and on an inner side, and, in particular, is advantageously formed via a single seal body.
A full side, as described by way of example in WO 2018/197182 A2 (full side 114), should be understood as a planar configuration of a first end side of the piston extending substantially continuously over the cylinder cross section.
As in WO 2018/197182 A2 (stepped side 116), a stepped side should accordingly be understood as a substantially annular configuration of the present second end side, that is, which therefore does not form the piston in such a way that it can be subjected to pressure over the entire cylinder cross section on the second end side but instead provides only an annular space which can be subjected to pressure, in particular an annular space in the peripheral area of the second end side.
In the present case, the content of WO 2018/197182 A2 and its disclosure are fully incorporated into the present application by citation and are therefore also available as the content of the disclosure in this application. By way of example, reference is made for purposes of illustration to the embodiments in relation to FIG. 1, FIG. 2 and FIG. 5 of WO 2018/197182 A2, which are shown in this application as
In the context of one embodiment, this shows, by way of example, purely for purposes of illustration and in a manner that is not restrictive here, that—in accordance with the concept of the disclosure—the first end side is formed as a full side—which in that case is formed substantially in the manner of a dome—while the second end side is formed as an annular surface, which is in that case arranged substantially in an annular manner at the outer circumference to form a stepped side.
Other embodiments are possible; for example, the stepped side could also be only partially annular or form an inner annular space. The stepped side could also form a full inner space, which is therefore not limited only to a peripheral annular surface which can be subjected to pressure, as explained in the embodiments of the present application. Thus, a stepped side can relate to any relatively small stepped formation of a pressurizable surface on the second end side of the piston which is smaller than a full side of the first end side of the piston. Realistically, however, it is the substantially circular full side and the annular stepped side that have proven to be pressurizable and sealable with an annular seal, and this is thus at the forefront of the concept in the present case, as shown in this application in
Following these above-stated basic considerations regarding the piston shape and the seal, the seal is already advantageously formed as such via a profiled annular seal body having a circumferentially extending first annular lip on an outer side of the seal and a circumferentially extending second annular lip on an inner side of the seal. The seal body thus advantageously has a first and a second annular sealing lip on the outer and inner sides, respectively, for sealing the annular peripheral annular space on the stepped side of the piston on the outer side, on the one hand, and on the inner side, on the other hand, that is, for sealing the second compression volume with respect to the first compression volume.
Proceeding from this consideration, the disclosure has also recognized that, in order to achieve the object, it is advantageous in an improved way for the annular seal body to be formed as a sealing sleeve with a profile which is open in circumferential cross section, which has a profile base, and the profile wall of which is formed via the first annular lip and the second annular lip. It is therefore advantageous, in turn, if the profile wall of the profile is formed via the first annular lip and the second annular lip; however, the profile according to the disclosure is open in circumferential cross section and thus has an exposed profile base. In contrast to the previously known forms of the aforementioned prior art, the disclosure has recognized here that the circumferential cross section of the profile should be fundamentally open. The prior art, on the other hand, follows the approach that the circumferential cross section should also be provided with a sealing profile filling. The present disclosure follows a different insight; namely, an exposed profile base makes it possible not only to achieve the object in terms of good sealing but also to use the open profile for advantageous retention of the sealing sleeve.
According to the disclosure, in contrast to the prior art, it is thus further envisaged that the sealing sleeve is retained in a pressure-tight manner, by way of its profile base, on the stepped side, between a step-side piston ring arranged on the second end side and a compression-volume-side retaining ring.
This feature uses the, to this extent, exposed profile base of the open profile to retain the sealing sleeve at its profile base between a step-side piston ring and a compression-volume-side retaining ring.
The retention of the sealing sleeve by way of its profile base between the step-side piston ring arranged on the second end side and the compression-volume-side retaining ring is furthermore configured to be pressure-tight and thus provides a pressure-tight configuration of the overall sealing arrangement including the sealing sleeve, the piston ring and the retaining ring; in other words, like a previously known solid-profile seal body but now with improved structure and stability and retention of the overall sealing arrangement. This significantly boosts the durability and pressure tightness of the sealing arrangement.
The retention of the sealing sleeve at its profile base between the step-side piston ring on the one hand and the compression-volume-side retaining ring on the other hand thus results in secure structural retention and also pressure-tight retention, which avoids a pressure loss along the contact surface between the profile base, the piston ring and the retaining ring and, on the other hand, also supports the sealing effect of the sealing lips through the shaping of the profile base.
In order to achieve the object as it relates to the device, the disclosure furthermore also leads to a compressed-air supply system and a vehicle having the compressed-air supply system.
A compressed-air supply system according to the disclosure is configured for operating a pneumatic system having a compressor and has:
The object as it relates to the method is also achieved by a method that uses the piston according to the disclosure. A method for operating a compressed-air supply system includes the following steps:
Even if the embodiments described here provide for series connection of a first compression volume and a second compression volume—generally in the form of a series connection of two compressor stages of what is thus a multi-stage compressor—it should nevertheless be understood that the concepts of the disclosure is not limited thereto. Alternatively, in another embodiment, the concepts of the disclosure can also be implemented in a multi-stage compressor whose two or more compressor stages are implemented in the form of a parallel connection—generally, therefore, in the form of a parallel connection of two compressor stages of what is thus a multi-cylinder compressor.
It is advantageous to provide for the first end side to be in the form of a full side and the second end side to be in the form of a stepped side, wherein, on the second end side, the piston carries a sealing arrangement at least one seal, which seals the first compression volume with respect to the second compression volume.
In particular, provision can be made for
Provision is advantageously made for the annular seal body to be formed as a sealing sleeve with a profile which is open in circumferential cross section, which has a profile base, and the profile wall of which is formed via the first annular lip and the second annular lip.
A pressure-tight configuration of the retention of the profile base between the piston ring and the retaining ring can expediently be configured in the manner explained as a preferred possibility in the context of the embodiments. A preferred embodiment, specifically of the anchoring or notching or similarly reinforced connection between the profile base, the piston ring and the retaining ring, is suitable for this purpose in principle.
Reinforced attachment of the profile base between the piston ring and the retaining ring preferably includes the profile base resting flat against a surface of the piston ring and a surface of the retaining ring, for example, embedding in the context of a mount. In addition, notching or guiding elements can be provided, which engage in an indentation or the like.
The profile base or correspondingly abutting surfaces of the profile against the corresponding piston surface or retaining ring surface can be slightly curved and, to this extent, can have a guiding action and, in addition, can nevertheless offer free space for a movement of the sealing lip.
In particular, the outer side of the seal, in particular of the sealing body, is in circumferential contact with a cylinder inner wall, and the inner side of the seal, in particular of the sealing body, is in circumferential contact with a web wall inner side of the cylinder.
In particular, provision is made for the seal to have an annular seal body with the first annular lip radially on the outside of the seal body and a second annular lip radially on the inside of the seal body. For this purpose, provision is advantageously made for the seal to have an annular seal body with:
In the context of an embodiment, it is envisaged that the retaining ring rests in the open profile of the sealing sleeve. This has the advantage that the retaining ring can, as it were, be fitted into the circumferential cross section of the open profile; to this extent, therefore, the retaining ring substantially follows the open profile corresponding to the circumferential cross section in its configuration.
For this purpose, the retaining ring can be rounded in the aforementioned manner on its base surface resting against the profile base in order, on the one hand, to allow the sealing lips to pivot and, on the other hand, like the base surface of the piston ring, to enable it to have further structural elements, which implement the sealing of the base surface of the retaining ring and the sealing of the piston ring with respect to the profile base.
It is likewise possible for the piston ring to have a base surface that is, as it were, gripping, which is correspondingly curved or arched. For example, the piston ring can have a substantially convex curvature on its base surface, and the retaining ring can have a correspondingly concave curvature on its base surface, or vice versa, with the result that the profile base of the profile of the sealing sleeve is held between these matching convexly or concavely curved base surfaces, which may be provided with free space.
In particular, the sealing sleeve, which is profiled in circumferential cross section, can be formed with a free cross section which is substantially U-shaped at the circumference, forming an open annular groove, the groove wall of which is formed via the first annular lip and the second annular lip. A groove which is U-shaped to this extent has proven particularly advantageous for accommodating the retaining ring. In particular, the first annular lip and the second annular lip can preferably be formed via the groove wall in order to form a pressure-tight radial sealing effect against a radial cylinder wall.
The sealing sleeve can advantageously be formed in one piece. The sealing sleeve can have the profile base between a first annular lip and a second annular lip, and at least one penetration opening may be formed in the profile base. However, the sealing sleeve can also be formed in multiple pieces. It is thus possible, in the context of a particularly preferred embodiment, to provide for the sealing sleeve to form the profile base between a separate part having a first annular lip and a separate part having a second annular lip, leaving a gap to form a penetration opening in the profile base. A corresponding further embodiment is shown in
In a particularly preferred embodiment, provision is also made for the sealing sleeve to have spaced-apart penetration openings in the profile base, and for the retaining ring to be connected to the piston ring via the fixing elements. Fundamentally, the fixing elements can advantageously be configured as required in order to connect the retaining ring to the piston ring via the fixing elements in such a way that the piston ring, which is arranged on the second end side with its profile base between the step-side retaining ring and the compression-volume-side retaining ring, is thereby held in a pressure-tight manner on the stepped side. The fixing elements can be produced from metal or plastic, for example, or from some other suitable synthetic material. As a particularly advantageous possibility, provision can be made for this purpose for the fixing elements generally to engage through the penetration openings of the sealing sleeve. In particular, it has proven advantageous for the sealing sleeve to have a number of penetration openings in the profile base which corresponds to the number of fixing elements, wherein each fixing element engages through one penetration opening.
In principle, one or more fixing elements can be formed on the piston ring or one or more fixing elements can be formed on the retaining ring or else, in a further modification, one or more fixing elements can be formed on the piston ring and the retaining ring, for example, can be integrally formed on one or both of these.
Thus, in a first modification, it has proven advantageous for the piston ring to have a first number of fixing elements and for the retaining ring to have a second number of fixing grooves in order to implement a connection, in particular a positive or nonpositive connection, between the piston ring and the retaining ring; the first and second numbers are preferably the same, but do not necessarily have to be the same. For example, a first number of fixing elements can be held in a common single annular groove or in a second number of fixing grooves, wherein each of the fixing grooves accommodates exactly one fixing element. A corresponding embodiment is shown in
In a second modification, it has also proven advantageous for the retaining ring to have a first number of fixing elements and for the piston ring to have a second number of fixing grooves in order to implement a connection, in particular a positive or nonpositive connection, between the piston ring and the retaining ring. Here, too, the first and second numbers are preferably the same but do not necessarily have to be the same. For example, a first number of fixing elements can be held in a common single annular groove or in a second number of fixing grooves, wherein each of the fixing grooves accommodates exactly one fixing element. A corresponding embodiment is shown in
These and other variants have the advantage, in particular, that—in addition to holding the piston ring and the retaining ring together axially—namely in that the fixing elements engage through the penetration openings of the sealing sleeve, the sealing sleeve is held in a twist-proof manner between the piston ring and the retaining ring.
For this purpose, a fixing element can in principle expediently be configured in a variety of ways; for example, a comparatively secure configuration of a fixing element can be achieved in that the fixing element is formed as a clamping screw, wherein the clamping screw is screwed into a screw hole.
In particular, it may also be advantageous for a fixing element to be formed as a clamping tooth. The clamping tooth is advantageously configured to be held on a clamping stop or in a clamping fit. For this purpose, a clamping tooth can have a web-like configuration and have a clamping element or clamping catch on one web flank. The number of clamping teeth and/or the number of clamping grooves and/or the number of penetration openings are advantageously arranged along the circumference of the piston ring and/or retaining ring and/or sealing element. In a particularly advantageous manner, these are evenly spaced.
In particular, in a first modification, a clamping tooth is advantageously clamped in a clamping groove or fixed via an interference fit. A corresponding embodiment is shown in
In a second modification, a clamping tooth can pass through a clamping groove and be fixed via a clinch or rivet connection. A corresponding embodiment is shown in
In the context of a preferred embodiment, the piston ring can be arranged in that, in a first modification, it is secured on the second end side or, in a second modification, is formed in one piece with the latter. In particular, according to the first modification, this can be formed in one piece with the stepped side. In particular, it is possible, according to the second modification, for this to be formed separately and to be connected in a suitable manner to the stepped side; for example, it can be adhesively bonded, welded or connected materially in such a way. In simplified terms, the piston ring according to the first modification is advantageously formed as part of the piston directly on the piston and, according to the second modification, is advantageously connected in a fixed manner thereto.
In the context of a further preferred embodiment, at least one, in particular a number of one or more, sealing webs is advantageously formed on the piston ring and/or on the retaining ring, preferably at least one circumferential sealing web being formed. In particular, a sealing web can be arranged on the piston ring on the side facing the sealing sleeve and/or a sealing web can be arranged on the retaining ring on the side facing the sealing sleeve.
In this way, the sealing sleeve can be attached pressure-tightly to the piston ring and/or retaining ring in a particularly advantageous way via its profile base.
Advantageously, the sealing sleeve is also secured against an unintentional offset via a sealing web, that is, it is securely held in a position reliably predetermined by the sealing web. Overall, the sealing sleeve can be held pressure-tightly and securely on the stepped side in a particularly advantageous way via its profile base.
For example, in relation to the fixing element, a first sealing web can be arranged radially on the inside and, in comparison thereto, a second sealing web can be arranged radially on the outside relative to the fixing element. As a preferred option, it is possible in general for a number of sealing lips to be arranged offset in the radial direction with respect to one another and opposite one another on the piston ring and the retaining ring. As a preferred option, at least two, preferably circumferential, sealing webs of the piston ring and/or of the retaining ring are each arranged on the side facing the sealing sleeve.
In this regard, it has proven advantageous, in particular, for a sealing web on the retaining ring to be a radially inner sealing web, which is offset closer to the penetration opening than a sealing web on the piston ring, which, as a radially outer sealing web, is offset further away from the penetration opening in comparison.
In this regard, it is also possible in combination therewith, in a particularly preferred variant, with the same proviso, for a sealing web on the retaining ring to be a radially outer sealing web, which is offset closer to the penetration opening than a sealing web on the piston ring, which, as a radially inner sealing web, is offset further away from the penetration opening in comparison. In this particularly preferred variant, it is possible as it were for the sealing webs which are offset further away from the penetration opening to be arranged on the piston ring, and for the sealing webs which are offset closer to the penetration opening in comparison therewith to be arranged on the retaining ring.
In addition or alternatively to this, provision can also be made for a sealing web on the retaining ring to be a radially outer sealing web, which is offset further away from the penetration opening than a sealing web on the piston ring, which, as a radially inner sealing web, is offset closer to the penetration opening in comparison.
In this regard, it is also possible in combination therewith, in a particularly preferred variant of this alternative too, with the same proviso, for a sealing web on the retaining ring to be a radially inner sealing web, which is offset further toward the penetration opening than a sealing web on the piston ring, which, as a radially outer sealing web, is offset closer to the penetration opening in comparison. In this particularly preferred variant, it is possible as it were for the sealing webs which are offset further away from the penetration opening to be arranged on the retaining ring, and for the sealing webs which are offset closer to the penetration opening in comparison therewith to be arranged on the piston ring.
The piston ring and the retaining ring are each advantageously produced from a synthetic material; in particular, they are made of a synthetic material. The piston ring and the retaining ring can also advantageously be connected to one another and/or to the sealing sleeve via an adhesive joint and/or ultrasonically welded joint.
In particular, it has proven advantageous in the context of a further preferred modified embodiment, for the retaining ring—alternatively to a ring formed as a separate part—to be formed by filling a preferably U-shaped annular space of the sealing sleeve with synthetic material. This has the aforementioned advantage that a U-shaped groove, which is to this extent preferred, can accommodate the retaining ring. In particular, the first annular lip and the second annular lip can preferably be formed via the groove wall in order to form a pressure-tight radial sealing effect against a radial cylinder wall. In addition, it is advantageously possible in this modified embodiment for a retaining connection to be formed between the piston ring and the sealing sleeve and the retaining ring.
Irrespective of the above-explained arrangement or positioning of a sealing web and irrespective of the material of the piston ring and/or the retaining ring, it has proven advantageous for a sealing web to be configured in such a way that it presses completely or partially into the profile base of the sealing sleeve or can penetrate in another way into the profile base of the sealing sleeve or into the volume region thereof when the profile base is being fixed between the base side of the piston ring and the base side of the retaining ring. A sealing web is thus formed with an appropriately pointed penetration side, that is, advantageously a formed web edge toward the profile base of the sealing sleeve—for example ideally in the manner of a ridge. A hardness of the material, in particular the synthetic material, of the sealing web is advantageously greater than a hardness of the material, in particular the synthetic material, of the sealing sleeve or its profile base. Thus, the sealing web is generally and advantageously configured in such a way that, in order to connect the sealing sleeve by its profile base to the piston ring and/or retaining ring in a pressure-tight manner, it can deform the sealing sleeve; advantageously, however, it does not cut or cut into it so as to maintain its consistency.
Embodiments of the disclosure are now described below with reference to the drawing. These are not necessarily intended to represent the embodiments to scale; on the contrary, the drawing is executed in schematic and/or slightly distorted form, where useful for explanation. With regard to additions to the teachings directly recognizable from the drawing, attention is drawn to the relevant prior art. It should be borne in mind here that many modifications and changes relating to the form and detail of an embodiment can be made without departing from the general concept of the disclosure.
The invention will now be described with reference to the drawings wherein:
Compressors according to the concept of the disclosure are preferably used in a compressed-air supply system—this has resulted in special requirements with regard to compression performance and compactness.
However, a compressor according to the concept of the disclosure can also be used for other types of compressed-air source. It should also be understood that the compressor can be used not only preferentially in compressed-air supply systems or for the passenger car or commercial vehicle sector. In addition, there have also been applications for vacuum generators, in particular vacuum pumps. A compressed-air supply system is shown by way of example as a preferred embodiment in
In the present case, the air spring system is formed with an illustrative number of four air springs 210, wherein each air spring 210 is associated with one wheel of a vehicle 400 (not illustrated specifically). In the present case, the part of the vehicle 400 shown, in a purely symbolic way, is a support 410, which is formed in the vicinity of the wheel and can be raised when the air spring 210 is filled or lowered when the air spring 210 is vented. An air spring 210 includes an air bellows, referred to here as bellows 211, for holding compressed air and an air spring valve 212, which holds the compressed air quantity in the bellows 211 or releases it, or allows the bellows 211 to be filled with compressed air. The air spring valve 212 is formed as a controllable solenoid valve, here as a 2/2-way valve. In the present case, each of the air spring valves 212 is shown in a normally closed state owing to the spring force of a spring (not described in greater detail).
The air spring valves 212 are connected to a gallery line 220 configured as a manifold via suitable spring branch lines 221. Connected directly to the gallery line 220 is a voltage-pressure sensor 230, which is able to measure a pressure in the gallery line 220—and, given suitable switching of the air spring valves 212, also a pressure in the air springs 210. In conjunction with an accumulator system, that is, in the present case the accumulator 224, the pneumatic line 40 and the accumulator valve 41, the voltage-pressure sensor 230 can also measure an accumulator pressure. Pressure sensor signals can be transmitted to an air spring control system and/or a vehicle control system (not illustrated specifically in the present case) in order to initiate further control measures. In the present case, the pneumatic system 500 in the form of the air spring system is supplied with compressed air from the compressed-air supply system 200.
For this purpose, the pneumatic system 500 is connected to the compressed-air supply system 200 via a compressed-air connection 2. Compressed air can be fed to the compressed-air connection 2 via a pneumatic main line 30 from a compressed-air feed 10 having a compressor 100. Compressed air can also be fed to the compressed-air connection 2 from a pressure medium reservoir 224 via a further compressed-air connection 2′ and a further pneumatic line 40. The compressed-air supply system 200 has suitable isolating valves for the expedient selection of the type of feed of compressed air to the pneumatic system 500, namely a first isolating valve 31 in the pneumatic main line 30 and a second isolating valve 41 in the further pneumatic line 40. The first and second isolating valves 31, 41 are each configured as a controllable solenoid valve—here as a 2/2-way valve.
In
Overall, the compressed-air supply system 200 has a compressed-air feed 10 to which the main pneumatic line 30 is connected. In the pneumatic main line 30, the air dryer 222 is connected pneumatically in series on the compressed-air feed side and the first isolating valve 31 is connected pneumatically in series on the compressed-air connection side. A valve arrangement configured as a pneumatic parallel circuit is connected between the air dryer 222 and the first isolating valve 31.
The valve arrangement has a check valve 32, which opens automatically in the air admission direction B to the pneumatic system 500 and blocks in the venting direction E from the pneumatic system 500 to the air dryer 222. A restrictor 34, which allows bidirectional flow and acts as a regeneration restrictor, is arranged in a pneumatic line that is parallel to the main pneumatic line 30 and is connected as a bypass line 33. The restrictor 34 has a nominal width that is sufficient to provide a pressure drop when the pneumatic system 500 is vented with the first isolating valve 31 open such that an air dryer 222 sufficiently regenerates as part of a pressure swing adsorption process.
A compressed air flow guided in the venting direction E can be vented via a vent line 35 connected to the main pneumatic line 30 to a vent connection 3 leading to the environment U. A further isolating valve 36, which is to be opened for a venting process, is arranged in the vent line 35. Like the first and second isolating valves 31, 41, the further isolating valve 36 is configured as a controllable solenoid valve, namely here as a 2/2-way valve.
In a modification not shown here, a fundamentally different configuration of the pneumatic main line 30 and vent line 35 can also be provided, for example, with a suitable pilot-controlled solenoid vent valve arrangement or the like.
In the present case, the compressed-air feed 10 has a compressor 1100 configured according to the concept of the disclosure, which is described below with reference to the particularly preferred embodiment illustrated by way of example in
The component of the compressed-air feed 10, which in this respect is to be referred to as a compressed-air feed device, has a compressed-air outlet 124, to which the main pneumatic line 30 of the compressed-air supply system 200 can be connected. Furthermore, the compressed-air feed 10 has a charging connection 126, to which a pneumatic line 37 leading to the pressure medium reservoir 224 can be connected via a still further isolating valve 38.
The pressure medium reservoir 224 is connected to the pneumatic line 37 via the abovementioned second compressed-air connection 2′. The further pneumatic line 40 leading to the compressed-air connection 2 is also connected to the second compressed-air connection 2′. When the still further isolating valve 38 is open, compressed air can flow through the pneumatic line 37 only unidirectionally, namely in a further venting direction E′ as viewed from the pressure medium reservoir 224. For this purpose, the pneumatic line 37 has a further check valve 39, which opens automatically in the further venting direction E′ and blocks in the opposite direction. The pneumatic line 37 is thus configured to feed compressed air from the pressure medium reservoir 224 to the charging connection 126 of the compressed-air feed 10 when the still further isolating valve 38 opens.
Furthermore, the compressed-air feed 10 has an air feed connection 0, via which air can be fed in from an air feed L—filtered in a filter 52 of an intake line 51.
As can be seen from
A single piston 1112 of the compressor 1100, which can be subjected to pressure on both sides in the interior of the cylinder 1118, is driven for movement by a motor M via a drive shaft 102. In the present case, the cylinder 1118 with piston 1112 of the compressor 1100 is arranged on a single side of the motor M to form both compression volumes 104 and 106; in particular, it is arranged on a single side of the drive shaft 102.
As can be seen from the description of
The compressed-air feed or compressor 1100 has a connecting line 122 between the first compression volume 104 and the second compression volume 106. In the present case, the connecting line 122 is formed as a passage through a piston body of the piston 1112 and is therefore of particularly compact configuration. Owing to the comparatively short connecting line 122, the entire compression volume in the cylinder 1118 is kept small, thus enabling a particularly high compression pressure amplitude to be achieved.
If necessary, the availability of compressed air, that is, in particular, a compressed air quantity, can be increased even further by feeding further pressure medium to the second compression volume 106 via the second, optionally usable charging connection 126 and—in a so-called boost mode—further compressing it in the second compression volume 106 together with the compressed air of the first compression volume 104, which has been highly compressed, and making it available in the compressed-air outlet 124. Various embodiments that follow the concept of the disclosure are illustrated below for such a compressor 1100, for which further areas of application are conceivable in addition to the application illustrated in
In the present case, the rotary connection 162 is achieved via a connecting rod bearing 152. The drive shaft 102 and the eccentrically arranged shaft section 132 are part of a rotating part 131 of the drive.
The connecting rod 128 has a piston side 128.1 facing the piston 1112 and a drive side 128.2 facing the drive shaft 102.
The drive shaft 102, in turn, performs a rotary movement D about an axis of rotation extending through a point S1 perpendicularly to the section plane. Owing to the rigid connection of the drive shaft 102 to the eccentrically arranged shaft section 132 and owing to the offset of the two points S1 and S2, a rotary movement of the drive shaft 102 leads to a deflection H of the piston in the stroke direction.
Furthermore, a rotationally symmetrical cylinder inner web 110 having an L-shaped cross section and extending radially inward from the cylinder inner wall 119 is arranged within the cylindrical cavity enclosed by the cylinder 1118. Owing to the L-shaped cross section, the cylinder inner web 110 has on its inner side a web wall 111 directed in the direction of the piston 1112. Thus, an annular space open in the direction of the piston 1112 is formed by the inner wall of the cylinder 1118 and the cylinder inner web 110, the space forming the second compression volume 106.
On the side facing away from the connecting rod 128, the piston 1112 has a first end side 113 configured as a full side 114, which, together with the inner wall of the cylinder 1118, delimits the first compression volume 104.
On the side facing the connecting rod 128, the piston 1112 furthermore has an annular piston step, which is formed in the form of a hollow cylinder, the outer wall of which is congruent with the outer wall of the piston 1112 at the level of the full side 114, and which is closed off on the side of the piston 1112 opposite the full side 114 by a second end side 115 configured as a stepped side 116.
The cylinder 1112 is furthermore configured in such a way that the piston 112, in particular the side facing the connecting rod 128 with the stepped side 116, can move in an oscillating manner within the annular space formed by the cylinder inner web 110 and the inner wall of the cylinder 1118. The second compression volume 106 is formed by the boundary of the virtually annular space formed by the cylinder inner web 110, the inner wall of the cylinder 1118 and the stepped side 116.
The piston 1112 furthermore has a seal 138, which is shown schematically here and, in the embodiment shown schematically here and also in the preferred embodiments of
The seal 1138 in the form of a sealing arrangement according to concepts of the disclosure—as illustrated in relation to the preferred embodiments of
For this purpose, the seal 1138 basically has an outer side 1138.1 and an inner side 1138.2. The outer side 1138.1 of the seal 1138 is arranged at the outer circumference, that is, the outer side of the—by way of simplified description—annular seal 1138 as part of a sealing arrangement, which will be explained below, and thus establishes continuous circumferential contact with an cylinder inner wall 119, which, in particular, forms a cylindrical cavity. The inner side 1138.2 of the seal 1138 is arranged on the inner side, that is, at the inner circumference of the—by way of simplified description—annular seal 1138 and thus establishes continuous circumferential contact with a web wall inner side 109. Via the arrangement and configuration of the piston 112, the cylinder 1118 and the cylinder inner web 110, it is therefore possible to accomplish the sealing of both compression volumes 104, 106 with a comparatively small number of seals or sealing arrangements, in particular just a single seal or sealing arrangement 1138.
Furthermore, a check valve 130, which is held in the closed state by a spring force F, is arranged within the piston 1112 as a further connection between the first compression volume 104 and the air feed connection 120 or the crankcase interior 160. The check valve 130 thus enables air in the first compression volume 104, the pressure of which exceeds a certain maximum value, in particular one that is potentially damaging to the compressor, to escape into the environment via the air feed connection 120. Alternatively, the check valve 130 can also be arranged in such a way that the air escapes directly into the crankcase interior 160 or the environment U, that is, without being guided via the air feed connection 120.
A connecting line 122 is furthermore arranged within the piston 1112 between the first compression volume 104 and the second compression volume 106. This connecting line 122 forms a gas-conducting connection of the two compression volumes 104 and 106. In the present case, analogously to the air feed valve flap 142, it has a connecting valve flap 144, which ensures that air flows through the connecting line 122 in only one direction, namely from the first compression volume 104 to the second compression volume 106. Accordingly, the connecting valve flap 144 closes counter to the rising pressure as the second compression volume 106 is reduced in size, and opens during enlargement, thus enabling air to flow from the first compression volume 104 into the second compression volume 106. The air compressed in the second compression volume 106 can be made available to consumers of a pneumatic system 500 via a compressed-air outlet 124, in particular via a compressed-air supply system 200.
Also arranged in the cylinder 1118 is a charging connection 126, which leads to the second compression volume 106 and has a charging valve flap 146. Via the charging connection 126, the second compression volume 106 can be fed with air which was compressed at a previous time, for example, and is stored and held ready in a pressure medium reservoir 224.
In this way, the power of the compressor 1100 can be briefly increased, in particular in order to make compressed air available more quickly. Here, the charging valve flap 146 ensures that air flows exclusively into the second compression volume 106 via the charging connection 126 and cannot escape via the charging connection 126.
Furthermore, the piston 1112 does not have a cylindrical shape but a cross section that is variable along a piston axis A. In this embodiment, the piston 1112 has a cross section with a piston secondary diameter KN at the level of the full side 114. On the stepped side 116, in contrast, the piston 1112 has a piston main diameter KH which is greater than the piston secondary diameter KN. Owing to these different diameters and the profile of the piston diameter between the stepped side 116 and the full side 114, there is a variable, substantially non-cylindrical profile of both an outer side 1112.1 and an inner side 1112.2 of the piston 112, which results in the piston 1112 being virtually dome-shaped. In particular, such a configuration ensures mobility of the piston 1112 within the cylinder 1118, in particular despite the wobbling movement of the piston 1112.
The piston main diameter KH may not be greater than the diameter of the cylinder 118, but it is possible and even expedient if the diameter of the outer side 138.1 of the seal 138 is greater than the piston main diameter KH and also than the diameter of the cylinder 118. This makes it possible for the piston 1112, together with the seal 138, to produce a seal between the first compression volume 104 and the second compression volume 106 or between the second compression volume 106 and the crankcase interior 160, despite the wobbling movement of the piston 1112 and the resulting openings and gaps between the piston 1112 and the cylinder 1118 or the piston 1112 and the web wall 111.
At the same time, despite the larger diameter of the outer side 1138.1 of the seal 1138, the movement of the piston 1112 is not significantly impeded or blocked since the seal 1138 of the sealing arrangement according to concepts of the disclosure is preferably formed from an elastic material.
In the present case, the shape of the piston 1112 is of virtually dome-shaped configuration, and therefore the piston is configured to match a dome-shaped section 164 of the cylinder 1118. The piston 1112 has an outer side 1112.1 and an inner side 1112.2. In particular, owing to its dome-shaped configuration, the piston 1112 —analogously to the embodiment shown in
It is furthermore possible, in particular, to provide a check valve 130, an air feed connection 120, a connecting line 122, an air feed valve flap 142, a connecting valve flap 144, a charging valve flap 146, and a compressed-air outlet 124 and a charging connection 126. These features correspond essentially to the features already symbolically represented in
In contrast to the embodiment illustrated in
Even if, in the embodiment described here, the connecting line 122 provides for series connection of the first compression volume 104 and the second compression volume 106—generally in the form of a series connection of two compressor stages of what is thus a multi-stage compressor—it should nevertheless be understood that concepts of the disclosure are not limited thereto. Alternatively, in another embodiment, the concepts of the disclosure can also be implemented in a multi-stage compressor whose two or more compressor stages are implemented in the form of a parallel connection—generally, therefore, in the form of a parallel connection of two compressor stages of what is thus a multi-cylinder compressor.
The seal 138a includes a seal body 139a which has a first annular lip 139.1a and a second annular lip 139.2a. The first annular lip 139.1a is arranged on the outside of the seal body 139a in a radial direction RR in such a way that it extends in an axial direction RA in the direction of a second compression volume 106. In particular, the first and/or second annular lip 139.1a, 139.2a have/has a free end that is arranged in the second compression volume 106.
The second annular lip 139.2a is arranged on the inside of the seal body 139a in a radial direction RR. It too extends in an axial direction RA in the direction of the second compression volume 106. The seal body 139a is secured on a stepped side 116 of a piston 1112.
The embodiment of the seal 1138 of the sealing arrangement according to concepts of the disclosure, which is a further preference that goes beyond the above, will be explained in more detail with reference to preferred embodiments of a piston of
The seal 1138 of the sealing arrangement according to concepts of the disclosure proves to be a further improvement for implementing a function of a powerful, in particular two-stage, compressor in a configuration that is as compact and robust as possible.
That is, the embodiments of a piston of
Here and below, for the sake of simplicity, the same reference sign is used for the same or similar features or features with the same or a similar function; however, a distinction is made specifically between the embodiments of a sealing arrangement 1001, 1002, 1003, 1004, 1005, 1006 corresponding to the further
In this regard,
In the present case, the piston 1112 is shown in a schematically illustrated cylinder 1118 with a schematically illustrated cylinder inner wall 119. The first end side 113 of the piston can be seen to be configured as a full side 114.
Thus, the piston 1112 is shown schematically in the cylinder 1118 in
All the preferred embodiments of the sealing arrangement 1001, 1002, 1003, 1004, 1005, 1006 implement the following features explained by way of example using the first sealing arrangement 1001, in a type of sandwich structure.
In the present case, according to the concept of the disclosure, the sealing arrangement 1001 has the sealing sleeve 1021, profiled in circumferential cross section, between the step-side piston ring 1011 and the compression-volume-side retaining ring 1031. In the present case, the sealing arrangement 1001 according to the first and further embodiments therefore has a step-side piston ring 1011 and, in order to form the annular seal body 1139, a sealing sleeve 1021 and retaining ring 1031 according to the first embodiment.
The sealing arrangement 1001 according to the first embodiment is illustrated in detail in
Likewise in the present case—as also in the case of the further embodiments of a further sealing arrangement 1001, 1002, 1003, 1004—the profiled sealing sleeve 1121—that is, like the further embodiments of the sealing sleeve 1022, 1023, 1024—is formed with a substantially U-shaped free cross section of the profile opening 1140 at the circumference, forming what is to this extent an open annular groove, that is, an annular groove open to the second compression volume 106, the groove wall of which is formed via the aforementioned first and second annular lips 1139.1, 1139.2 and the base of which is formed with the aforementioned profile base 1139.3.
Here, as in the other embodiments of the sealing arrangement 1001, 1002, 1003, 1004, the sealing sleeve 1021, 1022, 1023, 1024 is held in a pressure-tight manner at the profile base 1139.3 on the stepped side 116 of the piston, between the step-side piston ring 1011, 1012, 1013, 1014 and the compression-volume-side retaining ring 1031, 1032, 1033, 1034; this too is the case in all three embodiments of the sealing arrangement 1001, 1002, 1003, 1004, this being made clear in this respect by the same reference signs.
Likewise, as can be seen in
The rounded portion 1141 of the profile opening 1140 thus provides space for the transition of the sealing lips 1139.1, 1139.2 to the profile base 1139.3 in such a way that the curvature of the sealing sleeve 1021, 1022, 1023, 1024 can move between the convex curvature of the sealing side 1010 on the piston ring 1011, 1012, 1013 and the retaining side 1030 on the retaining ring 1031, 1032, 1033, or can adjust elastically to maintain the sealing effect. It can thus be understood that the curvature of the profile 1020 of the sealing sleeve 1021, 1022, 1023, 1024 is guided between the convex shape of the retaining side 1030 of the retaining ring 1031, 1032, 1033, 1034 or the sealing side 1010 of the piston ring 1011, 1012, 1013, 1014.
These, as well as the following features of the profile base 1139.3, are implemented in all the embodiments, and, in this respect, this is made clear by the use of the same reference signs.
The material of the profile base 1139.3 is configured to be sufficiently soft or elastic to receive the sealing webs 1119, which are here configured as sealing blades. The sealing webs 1119 are thus pressed into the profile base 1139.3 when fixing the profile base between the base side of the piston ring 1011, 1012, 1013 and the base side of the retaining ring 1031, 1032, 1033. The sealing webs 1119 serve to improve the sealing of the sealing sleeve 1021, 1022, 1023, 1024 at its profile base 1139.3 between the sealing side 1010 of the piston ring 1011, 1012, 1013 and the retaining side 1030 of the retaining ring 1031, 1032, 1033.
Moreover, as in all the embodiments of the sealing arrangement 1001, 1002, 1003, the profile base 1139.3 has penetration openings 1116 spaced apart along the annular circumference of the sealing sleeve. The sealing webs 1119 are formed on the sealing sleeve 1011, 1012, 1013 in order to form indentations in the profile base 1139.3 of the profile 1020. That is, in concrete terms, two small sealing blades (for example approximately 0.3 mm high), identifiable as small triangles, are formed circumferentially on the piston ring 1011, 1012, 1013 and on the retaining ring 1031, 1032, 1033, and are intended to press into the profile base 1139.3 of the profile 1020 of the sealing sleeve 1021, 1022, 1023, 1024 and thereby assist with sealing. The piston ring and the retaining ring are manufactured from aluminum and are to be sealed via the sealing blades.
The sealing webs are formed, on the one hand, on the outside as 1119.A and, on the other hand, on the inside as 1119.I, in order to increase the sealing effect; as explained above, this is done with the sealing webs 1119.A or 1119.I, respectively on the side of the piston ring 1011, 1012, 1013 and of the retaining ring 1031, 1032, 1033. That is, a first sealing web 1119.I is provided radially on the inside and a second sealing web 1119.A is provided radially on the outside in relation to the aforementioned sealing opening 1116. A first radially inner sealing web 1119.I is provided in each case on the piston ring 1011, 1012, 1013 and the retaining ring 1031, 1032, 1033; if appropriate, it can also be provided only on a piston ring or only on a retaining ring. Similarly, a second sealing web 1119.A can be provided radially on the outside of the piston ring 1011, 1012, 1013 and the retaining ring 1031, 1032, 1033, or only on the piston ring or only on the retaining ring.
In the present case, the formation of in each case two circumferential sealing webs 1119.A or two circumferential sealing webs 1119.I has proven advantageous, and therefore the piston ring 1011, 1012, 1013 has two circumferential sealing webs 1119.I, 1119.A and the retaining ring 1031, 1032, 1033 likewise has two circumferential sealing webs 1119.I, 1119.A, wherein in each case one of the circumferential sealing webs 1119.I, 1119.A is arranged radially inside the penetration openings 1116 and one is arranged radially outside the penetration openings 1116.
In the present case, it has also proven advantageous for the radially inner sealing webs 1119.I to be arranged offset relative to one another, wherein the sealing web 1119.I of the retaining ring 1031, 1032, 1033 is offset radially somewhat outward, that is, closer to the penetration opening 1116. In contrast, the radially inner sealing web 1119.I of the piston ring is offset radially somewhat inward in comparison to the sealing web 1119.I of the retaining ring.
However, both sealing webs 1119.I are offset with their apex ridges only to an extent such that they still overlap; in the present case, the apex ridge of one sealing web 1119.I lies opposite a flank of the other sealing web 1119.I. In the same way, a sealing web 1119.A of the retaining ring is offset radially somewhat closer to the penetration opening 1116, that is, offset radially further inward, in comparison with the sealing web 1119.A of the piston ring, which is offset radially somewhat outward. Both sealing webs 1119.A overlap insofar as their apex ridges are each arranged opposite a flank of the opposite sealing web 1119.A. This arrangement of the sealing webs 1119.A 1119.1- and likewise in all three embodiments of the sealing arrangement 1001, 1002, 1003, 1004—is implemented in order to increase the sealing effect at the profile base 1139.3 of the sealing sleeve between the piston ring and the retaining ring.
Irrespective of the above-explained arrangement or positioning of a sealing web 1119, 1119.A 1119.1 and irrespective of the material of the piston ring 1011, 1012, 1013 and/or the retaining ring 1031, 1032, 1033, it has proven advantageous for a sealing web 1119.A 1119.1 to be configured in such a way that it presses completely or partially into the profile base 1139.3 of the sealing sleeve 1011, 1012, 1013 or can penetrate in some other way into the profile base 1139.3 of the sealing sleeve 1011, 1012, 1013 or into the volume region thereof when the profile base 1139.3 is being fixed between the base side of the piston ring 1011, 1012, 1013 and the base side of the retaining ring 1031, 1032, 1033. Thus, a sealing web is formed with an appropriately pointed penetration side, that is, advantageously a formed web edge toward the profile base of the sealing sleeve—ideally, for example, in the manner of a ridge, for example, of the aforementioned apex ridges. A hardness of the material, in particular the synthetic material, of the sealing web is advantageously greater than a hardness of the material, in particular the synthetic material, of the sealing sleeve or its profile base. Thus, the sealing web 1119, 1119.A, 1119.1 is generally and advantageously configured in such a way that, in order to connect the sealing sleeve by its profile base 1139.3 to the piston ring and/or the retaining ring in a pressure-tight manner, it can deform the sealing sleeve; advantageously, however, it does not cut it so as to maintain its consistency.
In the present case, the penetration openings 1116 are formed in the profile base 1139.3 for penetration by a fixing element, which, like the number of penetration openings 1116 in the profile base, are arranged circumferentially in a ring on the retaining ring and/or the piston ring. In principle, a fixing element can be configured in any suitable manner as a rounded, oval or even circumferentially extending, more or less wide stud, pin, peg or else a partial or full circumferential web that is relatively wide in comparison therewith.
The retaining ring 1031, 1032, 1033, 1034 or piston ring 1011, 1012, 1013, 1014 thus has—in both cases or alternatively in only one, or else alternately—preferably one fixing element 1113 for each penetration opening 1116, ensuring that the retaining ring 1031, 1032, 1033 is connected to the piston ring 1011, 1012, 1013, 1014 by the fixing elements 1113 that penetrate in this way; that is, by virtue of the penetration openings in the sealing sleeve, the sealing sleeve 1121, 112, 1123 is furthermore held at the profile base 1139.3 in a twist-proof manner between the piston ring and the retaining ring.
More specifically, by virtue of their circumferentially limited extent and fitting into the penetration openings 1116, the fixing pins visible in
The additional clamping effect is explained below and results in the sealing arrangement 1001, 1002, 1003, 1004, 1005, 1006 also maintaining its sandwich structure one on top of the other. As will be explained in detail with reference to the embodiments of the sealing arrangement 1001, 1002, 1003, 1004, 1005, 1006, it is found that the fixing elements 1113 can be implemented in different ways in terms of their configuration or attachment to the retaining ring and/or piston ring.
While, in the present case, the sealing sleeve 1021, 1022, 1023, 1024, 1025, 1026 has a corresponding number of penetration openings 1116 for the number of fixing elements 1113, it is also quite possible for this to be implemented in a different way. In particular, the piston ring 1011, 1013, 1015 (
Correspondingly, in the present case, according to the embodiment of
Furthermore, in the present case, the fixing elements 1113 are arranged in a uniformly spaced manner along the annular circumference, along the circumference of the piston and the retaining ring and/or of the piston ring or the retaining ring. In the present case, the fixing elements 1113 are illustrated and embodied as clamping teeth or short webs or pegs. Nevertheless, the fixing elements can also be formed as a number of clamping screws.
In the present case, the receptacles 1114 are illustrated and configured as clamping grooves or similar receptacles for the fixing elements 1113. Nevertheless, in the case where the fixing elements are formed as a number of clamping screws, the receptacles 1114 can also be formed as screw holes—this will be described with reference to
However, the configuration, illustrated here, of the fixing elements as clamping teeth has proven advantageous in comparison with the use of clamping screws for the fixing elements since locking of the clamping teeth 1113 in a clamping groove or bore or similar receptacle 1114, as explained below, can be implemented in a particularly advantageous manner.
Referring now to the first embodiment of a sealing arrangement 1001 according to
Referring to the second embodiment of the sealing arrangement 1002 according to
Referring to the third embodiment of a sealing arrangement 1003, it can be seen in
Here too, the illustrated sealing arrangement 1004 according to the concept of the disclosure has a sealing sleeve 1024, profiled in circumferential cross section, between the step-side piston ring 1014 and the compression-volume-side retaining ring 1034. In the present case, the sealing arrangement 1004 according to this fourth embodiment therefore has a step-side piston ring 1014 and, in order to form the annular seal body 1139 of a sealing sleeve 1024, and a retaining ring 1034 according to the fourth embodiment.
The annular seal body 1139 of the sealing sleeve 1024 forms the above-explained first annular lip 1139.1 on an outer side 1138.1 of the seal 1138 and the second annular lip 1139.2 on the inner side 1138.2 of the seal 1138. In the present case too, the sealing sleeve 1024 is formed as an annular seal body 1139, with a circumferential cross section shown in
Here too, the opening 1140 in the profile can be seen to be substantially rectangular, wherein the first and second annular lips 1139.1, 1139.2 each merge via a rounded portion 1141 into the profile base 1139.3. The profile wall of the profile 1020 provided with the profile opening 1140 is thus formed via the first and second annular lips 1139.1, 1139.2 and merges in a rounded manner into the profile base 1139.3. On the sealing sleeve 1024 too, this is the case over the entire circular ring-shaped annular circumference.
Likewise in the present case with the sealing arrangement 1004—as in the case of the above-explained embodiments of a further sealing arrangement 1001, 1002, 1003—the profiled sealing sleeve 1141—that is, like the further embodiments of the sealing sleeve 1021, 1022, 1023—is formed with a substantially U-shaped free cross section of the profile opening 1140 at the circumference; that is, forming what is to this extent an open annular groove, that is, an annular groove open to the second compression volume 106, the groove wall of which is formed via the aforementioned first and second annular lips 1139.1, 1139.2 and the base of which is formed with the aforementioned profile base 1139.3.
In the present case too, with the sealing arrangement 1004—as in the above-explained embodiments of the sealing arrangement 1001, 1002, 1003—the sealing sleeve 1024 is held in a pressure-tight manner at the profile base 1139.3 on the stepped side 116 of the piston, between a step-side piston ring 1014 and a compression-volume-side retaining ring 1034; this too is the case in all four embodiments of the sealing arrangement 1001, 1002, 1003, 1004, this being made clear in this respect by the same reference signs.
In the present case, a penetration opening 1116 is formed in the profile base 1139.3 for penetration by a fixing element, which, like the number of penetration openings 1116 in the profile base, is arranged circumferentially in a ring on the retaining ring and/or the piston ring. As explained above, a fixing element can in principle be configured in any suitable manner as a rounded, oval or even circumferentially extending, more or less wide stud, pin, peg or else a partial or full circumferential web that is relatively wide in comparison therewith.
The retaining ring 1034 and/or the piston ring 1014 thus have/has a fixing element 1113, preferably for each penetration opening 1116—in both cases or alternatively just one of the two, or both alternately —, with the result that the retaining ring 1034 is connected to the piston ring 1014 by the fixing elements 1113 that extend through it; that is, by virtue of the penetration openings in the sealing sleeve, the sealing sleeve 1124 is furthermore held at the profile base 1139.3 in a twist-proof manner between the piston ring and the retaining ring.
More specifically, by virtue of its circumferentially completely encircling extent and fitting into the penetration openings 1116, the fixing web that can be seen in
The sealing arrangement 1004 according to the fourth preferred embodiment is illustrated in detail in
In contrast to the above-explained embodiments of a sealing sleeve 1021, 1022, 1023, the sealing sleeve 1024 described and shown here is formed from two separate parts, as already indicated by hatching in
In this respect, the seal body parts designated here, the first part 1139A as the seal body part lying on the outside of the annular space and the second part 1139I as the seal body part lying on the inside of the annular space, are shown in an exploded view in view (i) of
The first and second seal body parts 1139A, 1139I thus do not come into contact with one another, even though together they form the sealing sleeve 1124 of the sealing arrangement 1138, with the outer side 1138.1 of the seal, designated in view (i) of
Rather, the first and second seal body parts 1139A, 1139I are in fact held at a distance—as shown in
The first and second, outer and inner, seal body parts 1139A, 1139I can thus be placed separately one inside the other while maintaining the clearance—which is here established in the form of the penetration opening 1116—and thus form a concentric ring arrangement with a clearance for the penetration opening 1116 maintained therebetween.
The annular web of the fixing element 1113, as shown in view (ii) of
Specifically, the retaining ring 1034 has the annular web forming the fixing element 1113 and can engage in the receptacle 1114 of the piston ring 1014 at the moment when the annular web of the fixing element 1113 engages in the penetration opening 1116, that is, passes through the clearance left between the first and second seal body parts 1139A, 1139I. While the fixing web of the fixing element 1113 thus engages in the receptacle 1114 of the piston ring 1014 and is clamped there, the collar 1034B of the retaining ring fixes the mutually spaced seal body parts 1139A, 1139I; in this way, it fixes them relative to one another on the piston ring 1014.
The above-explained convexly arched retaining side 1030 of the retaining ring 1034 illustrated in view (ii) of
Nevertheless, the present fourth embodiment of a sealing sleeve 1024—that is, the sealing arrangement 1004 formed from the first and second seal body parts 1139A, 1139I, which are to this extent in fact separate, and the retaining ring 1034—offers the advantage that the fixing element 1113 (in the form of a web running around the full circumference as a ring) of the retaining ring 1034 can be introduced into the penetration opening 1116, or inserted into the receptacle 1114 of the piston ring 1014 and fixed there, in a significantly simpler manner than in the above-explained embodiments of the sealing arrangement 1001, 1002, 1003. In other words, in particular the seal body parts 1139I and 1139A on the inside of the ring and on the outside of the ring, respectively, can be inserted separately into a gap between the aforementioned collar 1034B of the retaining ring 1034 and the groove 1014N of the piston ring 1014, that is, between the sealing side 1030 of the piston ring 1034 and the retaining side 1030 of the retaining ring 1034.
In very simplified terms, it has proven advantageous to introduce each of the seal body parts 1139A, 1139I separately between the piston ring 1014 and the retaining ring 1034 in order to form the sealing arrangement 1004, rather than, conversely, introducing the retaining ring 1034 into a sealing arrangement 1004 that is already intrinsically joined together, that is, having an annular seal body 1139 that is formed in one piece and has first and second annular lips 1139.1, 1139.2.
Adjustment of the fixing element 1113 in the penetration opening 1116 of the sealing sleeve 1024 is therefore eliminated in the present case, and angularly accurate adjustment of the fixing web of the fixing element 1113 in the receptacle 1114 is also eliminated since they can therefore be locked to one another independently of the angle of rotation.
In the fifth embodiment according to
In the case of the fifth embodiment shown in
Sealing sleeve 1025 too has a corresponding number of penetration openings 1116 for the number of fixing elements 1113; in the simplest case, these can be holes or threaded screw holes. Accordingly, in the present case, the retaining ring 1035 has a receptacle 1114 for a fixing element 1113 in the form of a screw; here, in the simplest case, this can therefore be a hole or a screw hole with a thread for the screw. In the present case, the hole or screw hole has a chamfer, which can be seen from view (i) of
In another embodiment, it is also possible in principle to conceive of some other kind of receptacle 1114, such as a groove in the retaining ring 1035 or a passage as in the retaining ring 1035. Moreover, the piston ring 1015 or the base of the piston 1112 has a receptacle 1114 for a fixing element 1113 in the form of a screw; here too, in the simplest case, this can be a hole or a screw hole with a thread for the screw. Here too, in another embodiment, a groove for a fixing element 1113 is also suitable, for instance. Corresponding receptacles, such as a groove or a passage, are identified by reference sign 1114 in
As can be seen in the sectional view (ii) of
The additional clamping effect ensures that the sealing arrangement 1005 also holds together in its sandwich structure, as can be seen in view (iii) of
In the sixth embodiment shown in
However, it is also possible for a retaining ring 1036 with fixing studs to be glued or welded as a one-piece part into the sealing sleeve 1026; for example, by ultrasonic welding. In this way, a material connection that can no longer be released is created between the retaining ring 1036 and the piston ring 1016 on the piston 1112, the connection holding fast the sealing sleeve 1026.
With reference to
In each case, the material of the profile base 1139.3 of such a sealing sleeve too is generally configured to be sufficiently soft or elastic to receive the sealing webs 1119, which are here configured as sealing blades or penetrate in some other way into the profile base 1139.3 of such a sealing sleeve too and are configured accordingly.
The sealing webs 1119 illustrated here in
Each of the sealing webs 1119 serves to improve the sealing of the sealing sleeve 1021, 1022, 1023, 1024, 1025, 1026 at its profile base 1139.3 between the sealing side 1010 of the piston ring 1011, 1011, 1012, 1013, . . . 1016 and the retaining side 1030 of the retaining ring 1031, 1032, 1033.
As can be seen from
In the embodiment of
As can be seen from
Conversely, the single sealing web 1119.K on the piston ring, shown in broken lines, is a radially inner sealing web and is offset further inward away from the penetration opening 1116. The single sealing web 1119.H on the retaining ring, shown in broken lines, is, on the other hand, a radially outer sealing web, and this is offset closer to the penetration opening 1116 in comparison.
In all the embodiments and variants of their arrangements, the sealing webs 1119 are formed as elements on the piston ring 1011, 1012, 1013, 1014, 1015, 1016 and/or the retaining ring 1031, 1032, 1033, 1034, 1035, 1036 by pressing into the profile base 1139.3 of a sealing sleeve and are thus configured to hold the latter in a twist-proof manner and, in particular, also to seal it. Thus, as already explained above, the sealing web 1119, 1119.K, 1119.H is generally and advantageously configured in such a way that, in order to connect the sealing sleeve by its profile base 1139.3 to the piston ring and/or the retaining ring in a pressure-tight manner, it can deform the profile base 1139.3 of the sealing sleeve; advantageously, however, it does not cut it so as to maintain its consistency.
Irrespective of the above-explained arrangement or positioning of a sealing web 1119, 1119.K, 1119.H and irrespective of the material of the piston ring 1011, 1012, 1013, 1014, 1015, 1016 and/or the retaining ring 1031, 1032, 1033, 1034, 1035, 1036, it has proven advantageous for a sealing web 1119, 1119.K, 1119.H to be configured in such a way that it presses completely or partially into the profile base 1139.3 of the sealing sleeve or can penetrate in some other way into the profile base 1139.3 of the sealing sleeve or into the volume region thereof when the profile base 1139.3 is being fixed between the base side of the piston ring 1011, 1012, 1013, 1014, 1015, 1016 and the base side of the retaining ring 1031, 1032, 1033, 1034, 1035, 1036. Thus, a sealing web is formed with an appropriately pointed penetration side, that is, advantageously a formed web edge toward the profile base of the sealing sleeve—ideally, for example, in the manner of a ridge, for example, of the aforementioned apex ridges. A hardness of the material, in particular the synthetic material, of the sealing web is advantageously greater than a hardness of the material, in particular the synthetic material, of the sealing sleeve or its profile base.
According to the concept of the disclosure, the seal 1138 is part of a sealing
As likewise described with reference to
In detail,
The electronic lines to the ECU and the pneumatic lines to the air springs 210 and the compressed-air supply system 200 are likewise shown; these include corresponding compression springs 300 on the wheel suspensions and the aforementioned compressed-air supply system 200, which is shown here in detail in perspective as an exploded drawing with an engine compressor and air dryer 222.
A compressed-air supply system 200 is operated in the context of the vehicle 400, including the following steps:
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.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 110 256.1 | Apr 2021 | DE | national |
This application is a continuation application of international patent application PCT/EP2022/0059438, filed Apr. 8, 2022, designating the United States and claiming priority from German application 10 2021 110 256.1, filed Apr. 22, 2021, and the entire content of both applications is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2022/059438 | Apr 2022 | US |
| Child | 18492364 | US |
