EP3615798B1 - Compressor device for the delivery of compressed air to a compressed air supply system - Google Patents

Description

The invention relates to a compressor arrangement for a compressed air supply to a compressed air supply system, for operating a pneumatic system, comprising: a compressor, in particular a compressor, with at least one cylinder and at least one connecting rod in a connecting rod plane, the at least one connecting rod further having a compressor piston and at least one connecting rod bearing, a drive with an axis of rotation and a drive shaft, as well as a housing, the drive shaft being mounted in at least one drive shaft bearing and having a connecting rod end and an end remote from the connecting rod, and the drive shaft having a connecting rod receiving section arranged eccentrically to the axis of rotation of the drive at the connecting rod end.

The invention also relates to a compressed air supply system for operating a pneumatic system.

Compressors, in particular compressors in compressed air supply systems in vehicles, are generally known. In general, when improving such a compressor, a long service life, robustness, efficiency and low-noise and low-vibration operation are important aspects.

Compressors which allow the crankshaft drive to be adjusted to the motor shaft for the purpose of reducing the bearing play and thus the generation of noise are known. So describes DE 10 2005 009 445 B4 a compressor unit for generating compressed air in a vehicle, with a piston compressor and a motor for driving the piston compressor, the piston of which is driven by the motor via a connecting rod / crank drive arrangement via a motor shaft, characterized in that the crank drive is adjustable in the longitudinal direction of the motor shaft on the motor shaft when assembling the compressor unit.

A compressor arrangement of the DE 10 2004 020 104 A1 shows a double piston for a compressor, with an elongated piston carrier, which has a piston at each end, and with a connecting rod running approximately parallel to the piston carrier, which is rotatably mounted by means of a drive shaft bearing on a pin of the piston carrier and spaced therefrom by means of a connecting rod bearing an eccentric of a drive device can be mounted; The drive shaft bearing and the connecting rod bearing therefore lie a distance above one another in approximately the same axial direction. In a central region which extends between the two pistons, the piston carrier contains an intermediate space which is dimensioned to accommodate the connecting rod in a freely movable manner and in which the connecting rod is accommodated in a freely movable manner.

Methods for direct mass balancing in piston engines are also known. DE 2424562 A1 describes a method of direct mass balancing. Direct mass balancing is characterized in that the piston has its center of gravity in its axis of rotation around the piston pin, a balance weight is attached to the connecting rod and the system of all oscillating parts is balanced so that the common center of gravity is in the axis of rotation of the crankshaft

The DE102013003513A1 describes a compressor arrangement for operating a compressed air supply system of a vehicle, comprising a compressor with an electric motor, which is formed as an electronically commutated, brushless direct current motor with a control circuit comprising power electronics and a pneumatic compressor, the electric motor being in the form of an external rotor motor.

The concept, in particular the designs of compressor arrangements presented at the beginning, are in need of improvement, in particular with regard to low-noise and low-vibration operation and the longevity of the compressor.

It is therefore desirable to improve the function of a compressor arrangement, in particular the mechanical coupling of drive and compressor, in particular with regard to these aspects, namely low-noise and low-vibration operation.

This is where the invention comes in, the object of which is to provide an arrangement, in particular a compressor arrangement, a compressed air supply system and a vehicle, in an improved manner, which in particular the above. Problems addressed.

The object relating to the compressor arrangement is achieved by the invention with a compressor arrangement of claim 1. The object relating to the compressed air supply system is achieved by the invention with a compressed air supply system of claim 16. The invention also leads to a vehicle of claim 17 with the compressor arrangement of claim 1 and / or the compressed air supply system of claim 16.

The invention is based on a compressor arrangement for a compressed air supply to a compressed air supply system, for operating a pneumatic system, comprising: a compressor, in particular a compressor, with at least one cylinder and at least one connecting rod in a connecting rod plane, the at least one connecting rod also having a compressor piston and at least one connecting rod bearing comprises, a drive with an axis of rotation and a drive shaft, as well as a housing, wherein the drive shaft is mounted in at least one drive shaft bearing and has a connecting rod-side end and an end remote from the connecting rod, and the drive shaft has a connecting rod receiving section arranged eccentrically to the axis of rotation of the drive at the connecting rod-side end having.

According to the invention it is provided that the at least one drive shaft bearing and the at least one connecting rod bearing are arranged in such a way that the at least one drive shaft bearing is at least partially located in the radial direction within the at least one connecting rod bearing.

This primarily means that viewed in a projection plane perpendicular to the axis of rotation - the outside diameter of the drive shaft bearing is completely within the inside diameter of the connecting rod bearing; this is exemplified in Figures 2A-2C shown. In the context of the further development, this can primarily mean that the drive shaft bearing is in such a way in the axial direction is shifted along the axis of rotation in the direction of the connecting rod bearing or the drive - so laterally - that it is located wholly or partially within the interior of the connecting rod bearing with regard to its axial extent. In particular, this can advantageously also mean that the drive shaft bearing is arranged displaced along the axis of rotation of the drive in the direction of the connecting rod bearing that it protrudes into a connecting rod bearing interior of the connecting rod bearing at a certain distance, referred to as overlap. The case that the drive shaft bearing is completely in the interior of the connecting rod bearing is referred to as complete overlap.

In particular with the simultaneous arrangement of the drive shaft bearing - viewed in the radial direction - within the connecting rod bearing, this leads to a particularly advantageous design.

In particular, the synergetic aim of the concept of the invention is to prevent negative mechanical effects such as vibrations, structure-borne noise and air-borne noise, both through the axially overlapping bearing arrangement and through the improved introduction of the connecting rod forces into the housing, as far as possible. This is achieved in particular by the axial arrangement of the first bearing or A-bearing within the connecting rod bearing as well as the frame-fixed fastening of the inner ring of the A-bearing on the axle journal fixed to the frame. In this way, in particular, tilting moments on the drive shaft bearings, in particular on a first bearing or A-bearing and axial forces acting on the drive shaft, are reduced or avoided in an advantageous manner. Low-noise and low-vibration operation is particularly important for vehicles in the passenger car sector, since here, in contrast to applications in the truck sector, the acoustic requirements are higher or more sensitive.

The concept preferably offers the basis for a compressor arrangement that functions in an improved manner, in particular a low-vibration and low-noise compressor arrangement.

Furthermore, a reduction in forces and / or moments and, in particular, a reduction in the dynamic loads and vibrations associated with the forces and / or moments lead to a gentler mode of operation, which has a positive effect on the efficiency and longevity of the compressor arrangement. In the present case, these loads include, in particular, tilting moments acting on the connecting rod bearing, which occur in a conventional drive shaft bearing due to shaft bending. The reduction or avoidance of such tilting moments by a bearing according to the concept of the invention leads to a better durability of the connecting rod; the connecting rod can be designed to be smaller and therefore lighter, especially in a constructive optimization.

Radial forces acting on the compressor piston and in particular the sealing collar are also reduced by the particularly bending moment-free mounting of the drive shaft according to the concept of the invention. This advantageously results in a longer service life of the compressor and drive components, in particular connecting rod bearings, drive shaft bearings, compressor pistons and / or cuff.

Advantageous further developments of the invention can be found in the subclaims and indicate in detail advantageous options for realizing the concept explained above within the scope of the task and with regard to further advantages.

As part of a particularly preferred development, the drive shaft in the compressor arrangement is mounted in the drive shaft bearing on the connecting rod end of the drive shaft in a bearing plane as the first bearing on a first bearing receiving section coaxially to the axis of rotation.

The development is based on the consideration that a distance in the axial direction between the bearing plane of the first bearing or A-bearing and the connecting rod plane leads to a bending moment, which in particular results in a deformation the drive shaft results. In the case of a rotating drive shaft, such a deformation can lead to possibly disadvantageous dynamic load conditions and the development of noise and vibrations. Such noise and vibration developments can be further intensified by bearing play that may increase over the operating time. Deformations of the drive shaft are due in particular to connecting rod forces which arise when the air is compressed by the movement of the compressor piston in the cylinder and which are passed into the drive shaft via the connecting rod bearing and / or the first bearing or A-bearing. The bending moment is proportional to the connecting rod forces and the distance in the axial direction between the bearing plane and the connecting rod plane.

The development has recognized that when the distance in the axial direction between the bearing plane of the first bearing or A-bearing and the connecting rod plane of the connecting rod is reduced, the bending moment acting on the drive shaft is reduced. A reduction can be achieved in particular if the first bearing or A-bearing is arranged in the radial direction within the connecting rod bearing. In particular, if the distance in the axial direction between the bearing plane of the first bearing or A-bearing and the connecting rod plane of the connecting rod bearing is completely avoided, a bending moment which is caused by connecting rod forces and acting on the drive shaft is completely avoided.

In particular, it is provided that the drive shaft is mounted in the drive shaft bearing located on an end remote from the connecting rod as a second bearing on a second bearing receiving section located coaxially to the axis of rotation at the end remote from the connecting rod.

Furthermore, it is provided in a preferred development that the bearings are arranged within the housing and / or on it. The housing can comprise the compressor arrangement and / or the drive and / or further components and house them, and particularly advantageously in a modular manner means, in particular, for the compressor arrangement and drive to be designed individually but can be assembled.

• der erste Lager-Aufnahmeabschnitt zur Aufnahme des ersten Lagers als ein zylindrischer Hohlraum ausgebildet, und/oder
• das erste Lager weiterhin auf einem gestellfest mit dem Gehäuse verbundenen und praktisch koaxial zur Drehachse angeordneten Achszapfen befestigt ist, wobei
• das erste Lager in dem zylindrischen Hohlraum zwischen dem ersten Lager-Aufnahmeabschnitt und dem Achszapfen sitzt.

Preferably in the compressor arrangement

• the first bearing receiving section for receiving the first bearing is designed as a cylindrical cavity, and / or
• the first bearing is also attached to an axle journal which is fixedly connected to the frame and arranged practically coaxially to the axis of rotation, wherein
• the first bearing is seated in the cylindrical cavity between the first bearing receiving section and the journal.

Furthermore, the development is based on the idea that a reversal of the fastening arrangement of the first bearing or A-bearing, namely the stationary or frame-fixed fastening of the inner ring and a rotatable mounting of the outer ring, a transfer of the connecting rod forces into the Housing allows. This is particularly the case because it is possible to fasten the first bearing or A-bearing fixed to the frame by means of an axle journal fixed to the frame at a small axial distance from the wall of the housing. Due to the small axial distance, an improved absorption of the connecting rod forces is possible, in particular without bending moments caused by connecting rod forces and particularly preferably without deforming the drive shaft or the axle journal.

In particular, it is provided that the first bearing is firmly seated on the journal and is firmly seated in the first bearing receiving section and connects the journal and the first bearing receiving section rotatably relative to one another. Specifically, this means that the bearing inner ring of the first bearing is fixed in place on the axle journal, for example by a suitable form-fitting, force-fitting or material-locking fastening method. Furthermore, the bearing outer ring of the first bearing is fixed to the bearing receiving section of the Drive shaft connected. In this way, a rotational relative movement between the axle journal fixed to the frame and the drive shaft around the axis of rotation is made possible.

It is advantageously provided that the compressor has several, in particular a first connecting rod and a second connecting rod. Specifically, this can mean that gas, in particular air, is compressed in two or more compression chambers. In this case, a two-stage compressor is implemented by arranging two cylinders, the cylinders each having a compressor piston and a connecting rod. These are in particular driven by a drive shaft and are preferably arranged such that the overall system is in a practically balanced state. A two-stage compressor leads in particular to the advantages of higher achievable efficiencies and compression pressures.

In particular, it is provided that the first connecting rod and the second connecting rod are arranged in such a way that the first connecting rod is arranged at a first bearing distance and the second connecting rod is arranged at a second bearing distance in the axial direction, ie in the direction of the axis of rotation, to the bearing plane. Specifically, this means that the first and the second bearing spacing can be selected depending on the structural requirements in such a way that, in particular, deformations of the drive shaft and loads on connecting rods and bearings can be minimized as far as possible. Particularly in the event that one connecting rod absorbs greater forces than the other, bending moments acting on the drive shaft can be minimized by reducing the bearing spacing from the connecting rod absorbing the greater forces. Furthermore, the setting of the bearing spacing can be used in an advantageous manner to produce a shaft bending, in particular to compensate for a deformation of the axle journal. This is in the drawing in Fig. 3 shown by way of example and in connection with the Fig. 3 further explained by way of example in the context of a preferred embodiment.

In a particularly preferred development, it is provided that the first connecting rod and the second connecting rod are arranged in such a way that the bearing plane is centered in the axial direction between a first connecting rod plane (already here for clarification: denoted by P1 in the drawing) and a second connecting rod plane (already here for clarification: designated in the drawing with P2). Specifically, this means that the first and the second connecting rod planes are arranged at an axial distance of the same amount, but in the opposite direction to the bearing plane. Although neither of the two connecting rod planes is in the bearing plane in this further development and therefore bending moments acting on the drive shaft occur, the axially central arrangement of the first bearing or A-bearing between the two connecting rods represents a compromise to minimize the bending moments caused by connecting rod forces.

In particular, it is provided that the compressor has a first connecting rod which is arranged in the bearing plane of the first bearing, the bearing distance between the connecting rod plane and the bearing plane is practically zero. Specifically, this means that the arrangement of the first connecting rod and the first bearing or A-bearing without axial spacing with a bearing arrangement according to the concept of the invention achieves a practically bending moment-free absorption of connecting rod forces.

This development is particularly suitable for single-stage compressors with a connecting rod and a cylinder. However, within the scope of this bending moment-free, simple connecting rod arrangement, as further described below, a two-stage compressor can also be implemented within a cylinder with a compressor piston that can be pressurized on both sides.

In particular, it is provided that the compressor has a first connecting rod which is arranged at an axial bearing spacing from the first bearing. Specifically, this means that the connecting rod forces acting on the drive shaft lead to a bending moment which, depending on the structural design of the drive shaft, can in particular lead to deformation. This deformation, in particular a bend in the drive shaft can be used advantageously, for example, to compensate for a deformation of the axle journal. This is in the drawing in Fig. 3 shown by way of example and in connection with the Fig. 3 further explained by way of example in the context of a preferred embodiment.

In the context of a particularly preferred development, it is provided that the first connecting rod and the compressor piston are rigidly connected to one another, in particular the compressor is designed as a wobble piston compressor. Specifically, this means that the connecting rod and the compressor piston are essentially constructed in one piece. This leads to the advantage that fewer moving parts have to be used to couple the drive and compressor piston and, if necessary, no guide elements are required for the piston to absorb lateral forces introduced by the connecting rod. Any gaps between the cylinder and the compressor piston resulting from the wobble kinematics are sealed in such an embodiment by means of suitable seals, in particular piston sleeve seals.

It is advantageously provided that the compressor is designed as a single-stage compressor. Specifically, this means that the gas, in particular the air, is compressed in a compression chamber. This compression chamber is formed by the interior of the cylinder and the side of the compressor piston opposite the connecting rod.

In particular, it is provided that the compressor is designed as a multi-stage compressor, in particular a two-stage compressor. Specifically, this means that the gas, in particular the air, is compressed in two or more compression chambers. Such a multi-stage compressor can be realized by the arrangement of several, in particular two, pistons, the pistons each having a compressor piston and a connecting rod. These are in particular driven by a drive shaft and are preferably arranged such that the overall system is in a practically balanced state.

In the case of a two-stage compressor, the gas can be compressed in two compression chambers, for example, which are each formed by a cylinder and a compression piston that can be pressurized on both sides. The side of the compressor piston opposite the connecting rod together with the interior of the cylinder located on this side of the compressor piston forms the first compression chamber. The side facing the connecting rod together with the interior of the cylinder located on that side of the compressor piston also forms the second compression chamber.

It is advantageously provided that the connecting rod bearing is formed as a roller bearing, in particular a ball bearing, needle roller bearing, cylindrical roller bearing, barrel bearing or similar roller bearing.

In concrete terms, this means that a bearing form is selected depending on the design requirements. Needle and cylindrical roller bearings and generally roller bearings with cylindrical rolling elements have a generally high radial load capacity due to the line contact with the running surface. In the case of a needle bearing, there is also the fact that it is relatively compact due to the small diameter of the rolling elements, and thus advantageously further reduces the installation space of the drive. Due to the osculation in the rolling contacts, ball bearings have a relatively high axial and radial load-bearing capacity. Due to the spherical design of the rolling elements and a spherical outer ring raceway, barrel bearings also allow a certain pendulum movement between the inner and outer ring. This makes it insensitive to misalignment and misalignment of the drive shaft with respect to the housing.

It is advantageously provided that the first bearing and / or the second bearing is formed as a plain bearing. Specifically, this can be achieved with a lubricated or lubrication-free plain bearing. This leads in an advantageous manner to a low-maintenance, particularly preferably maintenance-free, design of the rotatable connection, since it - apart from the relative movement between shaft and bearing - has no moving parts, in particular no rolling elements.

In particular, it is provided that the first bearing and / or the second bearing is non-positively fastened, in particular by a tolerance ring. Specifically, the tolerance ring can be formed by a metal spring ring, or a ring made of rubber or plastic with a suitable cross section, or a further suitable, compressible connecting element. Furthermore, the first bearing or A-bearing and / or the second bearing or B-bearing can alternatively and / or additionally also in other ways, for example positively by a locking ring arranged in the axial direction or non-positively or frictionally by thermal Shrink, be fixed. The attachment by means of a fastening element such. B. a tolerance ring can refer to both the inside of the inner ring and the outside of the outer ring of the respective bearing. Consequently, for the first bearing, for example, both a tolerance ring arranged between the cavity and the outer ring of the first bearing and between a tolerance ring arranged between the axle journal and the inner ring would be possible.

In order to achieve the object, the invention also leads to a compressed air supply system for operating a pneumatic system. This compressed air supply system has: an aforementioned compressor arrangement, an air dryer and a valve arrangement. Furthermore, the invention also leads to the solution of the object on a vehicle with a compressed air supply system and a pneumatic system, the compressed air supply system having a compressor arrangement according to the concept of the invention. A compressor arrangement according to the concept of the invention is particularly advantageous in the case of cars, since high acoustic requirements prevail in the field of cars and low-noise and low-vibration operation of the compressor arrangement is of great importance or is advantageous.

Embodiments of the invention will now be described below with reference to the drawing. This is not necessarily intended to represent the embodiments to scale; rather, the drawing, where useful for explanation, is shown in a schematic and / or slightly distorted form. With regard to additions to the teachings that can be seen directly from the drawing, reference is made to the relevant prior art. It must be taken into account here that various modifications and changes relating to the shape and detail of an embodiment can be made without deviating from the general idea of the invention. The features of the invention disclosed in the description, in the drawing and in the claims can be essential for the development of the invention both individually and in any combination. In addition, all combinations of at least two of the features disclosed in the description, the drawing and / or the claims fall within the scope of the invention. The general idea of the invention is not restricted to the exact form or the detail of the preferred embodiments shown and described below or restricted to an object that would be restricted in comparison to the object claimed in the claims. In the case of the specified measurement ranges, values lying within the stated limits should also be disclosed as limit values and be able to be used and claimed as required. For the sake of simplicity, the same reference symbols are used below for identical or similar parts or parts with identical or similar functions.

Fig. 1

eine Verdichteranordnung gemäß einer besonders bevorzugten Ausführungsform,

Fig. 2A - 2C

unterschiedliche Anordnungen von Antriebswellenlager und Pleuellager gemäß dem Konzept der Erfindung,

Fig. 3A - 3D

unterschiedliche Anordnungen von erstem Lager bzw. A-Lager und Pleuellager in verschiedenen Weiterbildungen, vor allem gemäß der bevorzugten Ausführungsform der Fig.1 aber insgesamt dem Konzept der Fig.2 folgend,

Fig. 4

eine schematische Darstellung der Durchbiegung von Antriebswelle und Achszapfen,

Fig. 5

eine stark vereinfachte, schematische Übersicht einer Druckluftversorgungsanlage,

Fig. 6

eine schematische Darstellung eines Fahrzeugs mit einer Druckluftversorgungsanlage.

Further advantages, features and details of the invention emerge from the following description of the preferred embodiments and with reference to the drawing; this shows in:

Fig. 1

a compressor arrangement according to a particularly preferred embodiment,

Figures 2A-2C

different arrangements of drive shaft bearings and connecting rod bearings according to the concept of the invention,

Figures 3A-3D

different arrangements of the first bearing or A-bearing and connecting rod bearing in different developments, especially according to the preferred embodiment of FIG Fig.1 but overall the concept of Fig. 2 following,

Fig. 4

a schematic representation of the deflection of the drive shaft and axle journal,

Fig. 5

a greatly simplified, schematic overview of a compressed air supply system,

Fig. 6

a schematic representation of a vehicle with a compressed air supply system.

Fig. 1 shows a compressor arrangement with a compressor 100 according to a particularly preferred embodiment of the invention. In a first cylinder 170, for the purpose of compressing air, a first connecting rod 140 with a first compressor piston 150 is moved up and down in an oscillating manner and practically along the axis of symmetry of the first cylinder 170. In the present case, the first compressor piston 150 is shown near top dead center, ie at the top end of the stroke path H. Due to the fact that the embodiment shown here is a wobble piston compressor, that is, the first connecting rod 140 and the first compressor piston 150 are rigidly connected, the oscillating movement is predominantly, but not completely, translational. The first connecting rod 140 and the first compressor piston 150 therefore perform a tumbling movement corresponding to the kinematics during the upward and downward movement.

Analogous to the first cylinder 170, a second connecting rod 141 with a second compressor piston 151 is moved up and down in a second cylinder 171 in an oscillating manner and practically along the symmetry axis of the second cylinder 171 for the purpose of compressing air.

However, an embodiment according to the concept of the invention would also be conceivable in which - as is widely used in piston compressors - the first compressor piston 150 with the first connecting rod 140 and the second compressor piston 151 with the second connecting rod 141 are each articulated, in particular by means of a bearing, are connected.

In addition to the two-stage compressor shown, single-stage compressors according to the concept of the invention are also possible. In a further development, a multi-stage compressor can also be formed by a single-piston compressor which, by means of appropriately graduated pistons and cylinders or by a piston that can be pressurized on more than one side, forms a plurality of compression chambers.

In the present development, the drive shaft 220 is supported in a housing 440 by means of a first, connecting-rod-side drive shaft bearing or A-bearing 360 and a second, connecting-rod-remote drive shaft bearing or B-bearing 362. Both the A-bearing 360 and the B-bearing 362 can be fastened by means of a tolerance ring 164, not shown here. This fastening, which in particular serves as a fixed bearing seat, can relate both to the inside of the respective bearing 360, 362 and to the outside of the respective bearing 360, 362.

Furthermore, in the present case the two cylinders 170, 171 are arranged practically opposite one another with regard to the axis of rotation A. Thus, these are advantageously arranged in such a way that the linear inertial forces of the system of moving masses, in particular the connecting rods, compressor pistons and sleeves, cancel each other out during the movement.

In the case of a single-stage, in particular single-piston, compressor, this canceling function of an opposing piston can be achieved by a counterweight. If the number of cylinders or pistons is greater than two, the cylinders must be similar to achieve a mass balance be arranged around the axis of rotation A, that the inertial forces balance each other out.

The connecting rods 140, 141 each have a connecting rod eye on their sides opposite the compressor piston 150, 151, which is used to hold a connecting rod bearing 160, 161. The connecting rod bearing 160, 161 also serves to connect the connecting rod 140, 141 in a rotatable manner to a connecting rod receiving section 320 of a drive shaft 220.

In the present case, the connecting rod receiving section 320 is integrally connected to the drive shaft 220; Nevertheless, it is just as possible for the connecting rod receiving section 320 and the drive shaft 220 to be designed in two pieces and to be joined together via a corresponding positive, non-positive or material connection.

The drive shaft 220 furthermore has, at an end PS on the connecting rod side, next to the outer connecting rod receiving section 320, an inner first bearing receiving section 380. The outer connecting rod receiving section 320 has a cylindrical outer shape which receives the inner ring of the connecting rod bearings 160, 161. The inner first bearing receiving section 330 has a cylindrical inner shape and is used to receive the first bearing or A-bearing 360. Both connecting rod bearings 160, 161 and the first bearing or A-bearing 380 and the second bearing or B-bearing 382 can be attached to the drive shaft 220 in a number of ways. In particular, this fastening can take place in a form-fitting manner, for example by means of suitable fastening elements, in a force-fitting manner by shrinking on, or by a combination of the aforementioned or other operating principles.

The A-bearing 360 is also connected to the housing 440 via a journal 450 fixed to the frame. This means that the inner ring of the A-bearing 360 is fixed in place on the journal 450, while the outer ring of the A-bearing 360 is mounted rotatably about the axis of rotation A. By including the The outer ring of the A bearing 360 in the first bearing receiving section 380, together with the mounting by the B bearing 362 at an end PF of the drive shaft 220 remote from the connecting rod, enables the rotational movement of the drive shaft 220. The axle journal 450 particularly advantageously enables connecting rod forces to be introduced into the wall of the housing 440 as directly as possible, without significant bending moments or significant deformations occurring as a result of bending moments.

Deformations of the journal 450 that actually occur can be reduced to a negligible level by appropriate dimensioning of the journal 450, in particular by increasing the journal diameter AD and / or reducing the journal lever AH.

In the present case, the first connecting rod bearing 160 is arranged in a first connecting rod plane P1 and the second connecting rod bearing 161 in a second connecting rod plane P2 in relation to the A-bearing 360 in such a way that the bearing plane LE of the A-bearing 360 is axially centered between the connecting rod planes P1 and P2 . In this way, according to the concept of the invention, it is advantageously achieved that, taking into account all the connecting rod forces occurring in both connecting rods 140, 141 during operation, a state of drive shaft 220 that is as low in bending moment as possible, in particular free of bending moment, is achieved.

In fact, because of the distance between the two connecting rod planes P1 and P2, bending moments continue to occur; However, the central positioning of the A-bearing 360 in the axial direction between the connecting rod planes P1 and P2 represents an optimum in terms of minimizing the bending moments caused by connecting rod forces. This central position results from the assumption of almost identical connecting rod forces in both connecting rods 140, 141 In the event of a deviation in the connecting rod forces occurring in one of the two connecting rods 140, 141, the A-bearing 360 and thus the bearing plane LE would be correspondingly axially in the direction of that connecting rod bearing 160 in order to minimize the bending moments or 161 to move where the larger connecting rod forces are absorbed.

To generate an oscillating stroke movement of the connecting rod 140, 141 and the compressor piston 150, 151, the connecting rod receiving section 320 is arranged eccentrically to the axis of rotation A of the drive shaft 220. This means that the axis of symmetry of the first bearing receiving section 380 lying on the axis of rotation A is arranged parallel but offset to the cylinder axis of the cylindrical connecting rod receiving section 320 lying on the eccentric axis Ex of the connecting rod bearings 160, 161.

The drive shaft 220 serves to transmit the rotary movement generated by a drive 200 to the connecting rods 140, 141. In the present case, the drive shaft 220 is driven by an electric motor 290.

According to the concept of the invention, the A-bearing 360 is arranged in the axial direction centrally between the connecting rod planes P1 and P2. In this way, bending moments acting on the drive shaft 220 are significantly reduced or avoided, since practically all connecting rod forces act essentially within the bearing plane LE and thus practically no or only a small lever arm can arise for a bending moment acting on the drive shaft 220.

Referring to Figures 2A to 2C a situation with a single connecting rod bearing 260 ′ and a single drive shaft bearing 260 is shown schematically in the present case. This situation also symbolizes an in Fig. 1 or Fig. 3 illustrated embodiment. In this respect, the connecting rod bearing 260 'stands Fig. 2 symbolic of a connecting rod bearing arrangement 160, 161 of the Fig. 1 or Fig. 3 and the drive shaft bearing 260 of FIG Fig. 2 symbolic of a drive shaft bearing assembly 360 of Fig. 1 or Fig. 3 .

In Figure 2A a further development is shown in which the connecting rod bearing 260 'and drive shaft bearing 260 partially overlap. This means that the driveshaft bearing 260 is shifted in the axial direction along the axis of rotation A in the direction of the connecting rod bearing 260 ′ such that it is partially located within the connecting rod bearing interior 190. This shift - present in the direction of the drive 200 according to FIG Fig. 1 (in the Figures 2A, 2B to the right) - is described by an axial distance SA between the axial center plane EP of the connecting rod bearing 260 'and the axial center plane EA of the drive shaft bearing 260. This shift can in an alternative modification also in the direction away from the drive 200 according to FIG Fig. 1 implemented (in the Figures 2A, 2B that would then be to the left).

The larger the axial distance SA is chosen, the larger the bending moments acting on the drive shaft 220 and caused by connecting rod forces, which according to the concept of the invention are to be reduced or avoided.

The axial distance with which the drive shaft bearing 260 protrudes into the connecting rod bearing interior 190 is referred to here as the overlap UD. The UD overlap results from the in Figure 2A apparent embodiment, from the width BP of the connecting rod bearing 260 ', the width BA of the drive shaft bearing 260 and the axial distance SA.

In the in Figure 2A The further development shown, the overlap UD is comparatively small, in particular the drive shaft bearing 260 protrudes less into the connecting rod bearing interior 190 at a distance UD that is less than half its axial width BA. This case of a "simple" overlap UD can be expressed by the following relationship: UD <0.5 * BA.

The concept of the invention can - in any case in principle, even if not preferred - be implemented in another embodiment, not shown here, if there is no overlap. It turns out that this would be acceptable in any case in the embodiment not shown here as long as the axial distance SA is sufficiently small to allow a lever arm for the drive shaft 220 acting bending moments caused by connecting rod forces. The value SA = BP + BA is regarded as a guide value for a maximum axial distance SA.

In Figure 2B a further possible arrangement of connecting rod bearing 260 'and drive shaft bearing 260 is shown. Here it is essential that the in Figure 2B apparent varied coverage UD 'of the embodiment of Figure 2B is greater than the UD coverage of the in Figure 2A illustrated training. The drive shaft bearing 260 protrudes into the connecting rod bearing interior 190 as a result of an enlarged overlap UD ', the enlarged overlap UD' being greater than half the axial width BA of the drive shaft bearing 260. This case of the enlarged and, in this respect, "predominant" overlap UD ' can be expressed using the following relationship: 0.5 * BA <UD '<BA.

For the development shown here it also applies that the axial distance SA compared to that in Figure 2A illustrated training, is reduced in size. This advantageously has the consequence that the lever arm for bending moments caused on the drive shaft 220 and by connecting rod forces is also reduced in accordance with the concept of the invention.

Figure 2C Finally, shows a third possible bearing arrangement in which the axial center plane EP of the connecting rod bearing 260 'and the axial center plane EA of the drive shaft bearing 260 coincide in a bearing plane E particularly advantageously. This means that the axial distance SA is equal to zero and thus there is practically no lever arm for forces conducted from the connecting rod 140 into the drive shaft 220. In this way, according to the concept of the invention, the creation of bending moments is avoided in a particularly advantageous manner. The fact that the drive shaft bearing 260 is arranged in the axial direction in such a way that it is located completely in the connecting rod bearing interior 190 leads to a clearly enlarged, namely "complete" overlap UD ", that is to say: UD" = BA.

Figures 3A-3D show different arrangements of A-bearings and connecting rod bearings or connecting rod bearings according to the concept of the invention.

In Figure 3A shows a bearing arrangement according to a development in which A-bearing 360 and connecting rod bearing 160 practically exactly overlap in the axial direction. This means that the bearing level LE and the connecting rod level P coincide in one level. Consequently, the bearing distance LA between A-bearing 360 and connecting rod bearing 160 is equal to zero. As a result, the connecting rod force FP introduced from a connecting rod 140, not shown here, via the connecting rod bearing 160 to the connecting rod receiving section 320 of the drive shaft 220 is transmitted directly, in particular without bending moment, to the A-bearing 360 and thus via the journal 450 into the wall of the housing 440 becomes.

In Figure 3B shows a bearing arrangement according to a further development of the invention. In this, the connecting rod bearing 160 is arranged on the connecting rod receiving section 320 and the A bearing 360 in the A bearing receiving section 380 in such a way that there is an offset in the axial direction between the connecting rod bearing 160 and the A bearing 360. Consequently, the connecting rod plane P of the connecting rod bearing 160 and the bearing plane LE of the A-bearing 360 lie parallel to one another in the axial direction at a bearing spacing LA. This results in particular that a bending moment caused by the connecting rod forces, which is formed from the connecting rod force FP and a lever arm with the length LA, acts on the connecting rod receiving section 320 of the drive shaft 220. Such a bearing arrangement can advantageously be used to compensate for a deformation of the axle journal 450 caused by a bending moment by a deformation of the drive shaft 220 specifically caused by the bearing spacing LA. The bending moment acting on the journal 450 results from the bearing force acting on the A-bearing 360 and the journal lever AH. This connection is shown below in Fig. 4 explained in more detail.

In Figure 3C a bearing arrangement according to a further development of the invention is shown by way of example. This training is about a compressor with two cylinders 170, 171, not shown here, and correspondingly two connecting rods 140, 141, also not shown here. In the present case, the corresponding connecting rod bearings 160, 161 are arranged axially next to one another on the connecting rod receiving section 320. For this purpose, the A-bearing 360 is arranged within the A-bearing receiving section 180 and on the axle journal 450 such that the bearing plane LE lies centrally in the axial direction between the connecting rod planes P1, P2. As in connection with Fig. 1 described, the central arrangement of the A-bearing 360 in the axial direction between the connecting rod bearings 160, 161 represents a compromise for minimizing the bending moments caused by connecting rod forces FP1, FP2, since due to the arrangement of the connecting rod planes P1 and P2 outside the bearing plane LG it is not completely free of bending moments Storage of the drive shaft 220 is possible. In the present case, the first connecting rod bearing 160 is arranged displaced by a first bearing spacing LA1 in the negative axial direction, that is to say in the direction of the wall of the housing 440 on which the journal 450 is attached. Furthermore, the second connecting rod bearing 161 is arranged in the positive axial direction, ie in the direction of the free end of the journal 450, by a second bearing spacing LA2, which in this case is equal to the first bearing spacing LA1 in terms of amount.

In Figure 3D shows a bearing arrangement according to yet another development of the invention. In contrast to the in Figure 2C Further development shown, the A-bearing 360 is arranged in relation to the connecting rod bearings 160, 161 in such a way that the bearing distances LA1 and LA2 are each of different sizes. In the case of connecting rods 140, 141 that are approximately equally loaded in terms of amount, this means that one of the resulting total connecting rod forces conducted into drive shaft 220 from both connecting rods 140, 141 and thus both connecting rod bearings 160, 161 does not essentially act within bearing plane E. The resulting, deliberately induced deformation can, analogous to that in Figure 3B Bearing arrangement described, can be used to compensate for the deformation of the journal 450.

Alternatively, in the event that one connecting rod is more heavily loaded than the other connecting rod, an in Figure 3D Bearing arrangement shown can be used specifically to take into account and compensate for this fact. It is assumed here, for example, that the connecting rod force FP2 acting on the second connecting rod bearing 161 is greater than the connecting rod force FP1 acting on the first connecting rod bearing 160. Consequently, the axial position of the A-bearing 360 is shifted in the direction of the more heavily loaded connecting rod bearing, in this case the connecting rod bearing 161, so that the second bearing spacing LA2 is smaller than the first bearing spacing LA1. This ensures that the larger connecting rod force FP2 acting on the connecting rod bearing 161 engages the drive shaft 220 in a connecting rod plane P2 which, in particular, is so close to the bearing plane LE that the resulting bending moments do not cause any critical deformation of the drive shaft 220. In this context, critical deformation refers to a deformation that leads directly or indirectly to one or more of the disadvantages mentioned at the beginning, in particular with regard to noise and vibration development as well as wear behavior.

Fig. 4 shows in a schematic representation a deflection of a drive shaft 220 and an axle journal 450. In this greatly simplified representation, the deformations are shown exaggerated. A connecting rod force FP that acts on the connecting rod bearing 160 is transmitted to the drive shaft 220 and thus to the A bearing 360. This force is finally conducted via the A-bearing 360 into the journal 450, where it leads to a bending moment due to the distance between the housing 440 and the A-bearing 360, which in turn results in a deformation of the journal 450, namely a pin deflection ZA . At the same time, the arrangement of A-bearing 360 and connecting rod bearing 160, in particular the arrangement of A-bearing 360 and connecting rod bearing 160 at an axial bearing spacing LA, ensures that a bending moment acts on drive shaft 220. This bending moment is opposite to the bending moment acting on the stub axle. This advantageously ensures that the drive shaft 220 is deformed in such a way that the forces acting on the B-bearing 362 are as small as possible, in particular transverse forces and Overturning moments act. The deformation of the drive shaft 220 thus partially or completely compensates for the pin deflection ZA.

Fig. 5 shows a greatly simplified, schematic overview of a compressed air supply system 500 with a compressor arrangement 1000 according to the concept of the invention for supplying a pneumatic system 600. The compressed air supply system 500 has an air intake 0 for sucking in fresh air, which continues to carry fluid, in particular gas, with an inlet of the compressor 100 , connected is. As part of the compressor arrangement 1000, the compressor 100 is driven by a drive 200 via a drive shaft 220. The compressed fresh air is also made available via a compressed air source 1, to which a branch 510 is connected. On the one hand, a vent 3 is connected to this junction 510 via a vent valve 520. On the other hand, an air dryer 520 is connected to the junction 510, which also leads to a compressed air connection 2. A compressed air reservoir 560 and the pneumatic system 600 are also connected to this via a gallery 570. The pneumatic system 600 can, for example, be an air suspension system or another pneumatic system, in particular a vehicle. Furthermore, individual valves, throttles and similar adjusting means as well as individual components, in particular the pneumatic system, are not shown in this illustration for reasons of clarity and simplicity.

Fig. 6 shows a schematic representation of a vehicle 800 - in the present case in the form of a car - with a compressed air supply system 500 and a pneumatic system 600. In vehicles in the passenger car sector, low-noise and low-vibration operation is of great importance because here, in contrast to applications in trucks -Area, the acoustic requirements are higher or more sensitive. The car vehicle 800 shown here by way of example, without restricting its applicability for trucks or other commercial vehicles, has four wheels 801, 802, 803 and 804, of which the two front wheels are shown here due to the sectional view. Analogous to the number of wheels, the pneumatic system 600 has four air springs 601, 602, 603 and 604, of which the two front air springs are shown here analogously to the wheels due to the sectional view. The air springs 601, 602, 603 and 604, which are respectively assigned to the wheels 801, 802, 803 and 804, are supplied with compressed air from the compressed air supply system 500 as part of the pneumatic system 600. The compressed air supply system 500 is connected in a fluid-conducting manner via the gallery 570 to the components of the pneumatic system 600, in this case the air springs 601, 602, 603 and 604 shown here.

The compressed air supply system 500 is shown greatly simplified in this illustration, so that only the compressed air reservoir 560 and the compressor 100 according to the concept of the invention are visible. The compressor 100 according to the concept of the invention can, however, in a modification not shown here, additionally or alternatively be used independently of the compressed air supply system. The concept preferably offers the basis for a compressor arrangement that functions in an improved manner, in particular a low-vibration and low-noise compressor arrangement. Furthermore, a reduction in forces and / or moments and, in particular, a reduction in the dynamic loads and vibrations associated with the forces and / or moments lead to a gentler mode of operation, which has a positive effect on the efficiency and longevity of the compressor arrangement.

List of reference symbols (part of the description)

0

Air intake

1

Compressed air source

2

Compressed air connection

3

Venting

100

compressor

140

First connecting rod

141

Second connecting rod

150

First compressor piston

151

Second compressor piston

160

First connecting rod bearing

161

Second connecting rod bearing

170

First cylinder

171

Second cylinder

164

Tolerance ring

200

drive

220

drive shaft

290

Electric motor

320

Connecting rod receiving section

360

First bearing, connecting rod end drive shaft bearing (A bearing)

362

Second bearing, drive shaft bearing remote from the connecting rod (B bearing)

370

cavity

380

First bearing receiving section (A-bearing)

382

Second bearing receiving section (B-bearing)

440

casing

450

Journal

500

Compressed air supply system

510

Junction

520

Vent valve

540

Air dryer

560

Compressed air storage

600

Pneumatic system

601, 602, 603, 604

Air spring

800

vehicle

801,802,803,804

wheel

1000

Compressor arrangement

A.

Axis of rotation of the drive shaft

AD

Axle journal diameter

AH

Journal lever

Ex

Eccentric axis

FP

Connecting rod force

FP1

First connecting rod force

FP2

Second connecting rod force

H

Stroke of the compressor piston

LA

Bearing spacing

LA1

First bearing clearance

LA2

Second bearing spacing

M.

Center plane, axial center plane of the A bearing

P1

First connecting rod level

P2

Second connecting rod level

PF

end of the drive shaft remote from the connecting rod

PS

end of the drive shaft on the connecting rod side

WA

Shaft deflection, deflection of the drive shaft

ZA

Pin deflection, deflection of the journal

BA

Drive shaft bearing width

BP

Big end bearing width

DAA

Drive shaft bearing outer diameter

SLIDE

Drive shaft bearing inside diameter

DAP

Big end bearing outer diameter

DIP

Connecting rod bearing inside diameter

E.

Storage level

EA

Axial center plane of the drive shaft bearing

EP

Axial center plane of the connecting rod bearing

UD

simple overlap

UD '

predominant overlap

UD "

complete coverage

Claims (17)

1. Compressor assembly (1000) for a compressed-air feed of a compressed-air supply system, for operating a pneumatic system (600), having:

   - a compressor (100) having at least one cylinder (170, 171) and at least one connecting rod (140, 141) in a connecting-rod plane (P, P1, P2), wherein the at least one connecting rod further has a compressor piston (150, 151) and at least one connecting-rod bearing (160, 161),

   - a drive (200) having an axis of rotation (A) and a drive shaft (220), and also a housing (440), wherein the drive shaft (220) is mounted in at least one drive shaft bearing (360) and has a connecting-rod-side end (PS) and a connecting-rod-remote end (PF), and

   - the drive shaft (220) has a connecting-rod-receiving portion (320) which is arranged eccentrically to the axis of rotation (A) of the drive (200) at the connecting-rod-side end (PS),
   characterized in that

   - the at least one drive shaft bearing (360) and the at least one connecting-rod bearing (160, 161) are arranged in such a way that the at least one drive shaft bearing (360) is situated at least partially within the at least one connecting-rod bearing (160, 161) in the radial direction.
2. Compressor assembly (1000) according to Claim 1, characterized in that

   - the drive shaft (220) is mounted in a connecting-rod-side drive shaft bearing, which is arranged at the connecting-rod-side end (PS) of the drive shaft (220) in a bearing plane (LE), as first bearing (360, A bearing) on a first bearing-receiving portion (380) arranged coaxially to the axis of rotation (A).
3. Compressor assembly (1000) according to Claim 1 or 2, characterized in that

   - the drive shaft (220) is mounted in a connecting-rod-remote drive shaft bearing, which is arranged at the connecting-rod-remote end (PF) of the drive shaft (220), as second bearing (362, B bearing) on a second bearing-receiving portion (382) arranged coaxially to the axis of rotation (A) at the connecting-rod-remote end (PF).
4. Compressor assembly (1000) according to one of the preceding claims, characterized in that the bearings (360, 362) are arranged within and/or on the housing (440) .
5. Compressor assembly (1000) according to one of the preceding claims, characterized in that

   - the first bearing-receiving portion (380) for receiving the first bearing (360) is designed as a cylindrical cavity (370), and/or

   - the first bearing (360) is further fastened on a journal (450) which is connected to the housing (440) in a frame-fixed manner and which is arranged practically coaxially to the axis of rotation (A), wherein

   - the first bearing (360) is seated in the cylindrical cavity (370) between the first bearing-receiving portion (380) and the journal (450).
6. Compressor assembly (1000) according to one of the preceding claims, characterized in that the first bearing (360) is seated fixedly on the journal (450) and firmly seated in the first bearing-receiving portion (380) and connects the journal (450) and the first bearing-receiving portion (380) such that they can be rotated relative to one another.
7. Compressor assembly (1000) according to one of the preceding claims, characterized in that the compressor (100) has a plurality of connecting rods, in particular a first and a second connecting rod (140, 141).
8. Compressor assembly (1000) according to one of the preceding Claim 6 or 7, characterized in that the first connecting rod (140) and the second connecting rod (141) are arranged in such a way that the first connecting rod (140) is arranged at a first bearing distance (LA1) and the second connecting rod (141) is arranged at a second bearing distance (LA2) in the axial direction, i.e. in the direction of the axis of rotation (A), from the bearing plane (LE).
9. Compressor assembly (1000) according to Claim 6 or 7, characterized in that the first and the second connecting rod (140, 141) are arranged in such a way that the bearing plane (LE) is situated in the axial direction centrally between a first connecting-rod plane (P1) and a second connecting-rod plane (P2).
10. Compressor assembly (1000) according to one of the preceding claims, characterized in that the compressor has a first connecting rod (140) which is arranged in the bearing plane (LE) of the first bearing (360).
11. Compressor assembly (1000) according to one of the preceding claims, characterized in that the compressor has a first connecting rod (140) which is arranged at an axial bearing distance (LA) from the first bearing (360).
12. Compressor assembly (1000) according to one of the preceding claims, characterized in that the first connecting rod (140) and the compressor piston (150) are rigidly connected to one another, in particular with the compressor (100) being designed as a wobble piston compressor.
13. Compressor assembly (1000) according to one of the preceding claims, characterized in that the compressor (100) is designed as a single-stage compressor or as a multistage compressor, in particular two-stage compressor.
14. Compressor assembly (1000) according to one of the preceding claims, characterized in that the connecting-rod bearing (160) is formed as a rolling bearing, in particular a ball bearing, needle bearing, cylinder roller bearing, barrel bearing or similar rolling bearing, and/or the first bearing (360) and/or the second bearing (362) are/is formed as a sliding bearing.
15. Compressor assembly (1000) according to one of the preceding claims, characterized in that the first bearing (360) and/or the second bearing (362) are/is fastened in a force-fitting manner, in particular by means of a tolerance ring (164).
16. Compressed-air supply system (500) for operating a pneumatic system (600), having:

    - a compressor assembly (1000) according to one of Claims 1 to 15,

    - an air dryer (520), and

    - a valve arrangement (540).
17. Vehicle (800), in particular a passenger car, having a compressor assembly according to one of Claims 1 to 15 and/or a compressed-air supply system (500) according to Claim 16 and a pneumatic system (600).

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