Abstract:
The present disclosure relates to an arrangement of auxiliary assemblies in a combustion machine including an electric machine which is operable as a generator and preferably also as a motor. The arrangement further includes an expansion machine, in particular an expansion machine of a waste heat recovery system for converting waste heat of the combustion machine or of an engine braking system into utilizable energy by way of a steam circuit, and a first group of auxiliary assemblies, including a water pump, a fuel predelivery pump, a high-pressure fuel pump, a steering assistance pump and an oil pump.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to an arrangement of auxiliary assemblies in a combustion machine. 
         [0003]    2. Description of Related Art 
         [0004]    Modern combustion machines have numerous auxiliary assemblies. Aside from auxiliary assemblies which are directly required for the operation of the vehicle, such as for example alternator, water pump or compressor, increasing use is being made of auxiliary assemblies which are intended to improve the comfort of the vehicle, for example air-conditioning compressors, steering assistance pumps, etc. Normally, said auxiliary assemblies are fastened to the vehicle engine and are driven by the latter via chain drives, belt drives, gearwheel drives or a combination of these. The greater the number of auxiliary assemblies provided in a vehicle, the more difficult it becomes in spatial terms for these to be fastened in a suitable manner to the vehicle engine, and the more cumbersome and complicated the required belt drives become. Such a multiplicity of auxiliary assemblies and belt drives or the like poses difficulties not only owing to the engine bay, which nowadays is generally of very tight dimensions. The installation and subsequent maintenance require a high level of outlay, and great care must be taken to rule out, for example, squealing noises or premature wear owing to alignment errors of the belt pulleys or owing to belts not having been tightened in accordance with specifications, or the like. 
         [0005]      FIG. 1  shows a perspective view of an arrangement  10 , known from the prior art, of auxiliary assemblies of an internal combustion engine. This is an internal combustion engine  1 , in the form of a diesel combustion machine, of a utility vehicle. The crankcase  2  is closed off at the bottom by an oil sump  19 . The top side of the internal combustion engine  1  is denoted by the reference designation  5 . On the front face side  4  of the internal combustion engine  1  there is situated a belt mechanism  6 , hereinafter referred to for short as belt drive, which is driven by the combustion machine. In the perspective view of  FIG. 1 , the reference designation  6   b  denotes the belt, and the reference designation  6   a  denotes a drive belt pulley. In a known manner, the belt drive drives a 24 V generator (alternator)  11 , a water pump  12  and a refrigerant compressor  13  of the air-conditioning system. The water pump  12  and refrigerant compressor  13  are likewise arranged, behind the fan  7 , on the front face side  4 , but on the rear part (not shown in  FIG. 1 ) of the front face side  4 , and thus on that side of the front face side  4  which is situated opposite the generator  11 . 
         [0006]    Also situated on the front face side  4  is a front gear drive (gearwheel mechanism) which is driven by the combustion machine and the gearwheels of which are encased by the front control case  51  and which are thus not visible in the illustration of  FIG. 1 . The front gear drive drives the fan  7  arranged on the front face side  4 , a high-pressure fuel pump  15  arranged laterally on the crankcase  2 , and an oil pump. Furthermore, a rear gear drive is provided, that is to say a gear drive which is arranged on the gearbox-side face side  3  of the internal combustion engine  1 , which gear drive is driven by the internal combustion engine. The rear gear drive is likewise encased by a rear control case  52 , and is therefore not visible in the illustration of  FIG. 1 . 
         [0007]    The rear gear drive drives an air compressor  14 , also referred to as air impeller, which is in the form of a piston-type compressor. The air compressor  14  supplies compressed air to a compressed-air system of the utility vehicle. The air compressor is fastened to a lower rear section of the lateral wall of the crankcase. At this location, an opening is provided in the crankcase  2 , via which opening the power flow between compressed-air compressor  4  and the rear gear drive is realized. 
         [0008]    The rear gear drive furthermore drives a steering assistance pump which is arranged on the air compressor  14 . The rear gear drive output furthermore, in a known manner, drives the camshaft drive input, and has a power take-off for the drive of, for example, a hydraulic pump for body systems of the utility vehicle (in each case not illustrated). 
         [0009]    By way of such a design, the available free structural space is virtually fully utilized for the arrangement of auxiliary assemblies such as are required for conventionally equipped motor vehicles. Problems however arise in the case of equipment with further auxiliary assemblies, for example if the utility vehicle is to be equipped with a system for waste heat recovery (WHR), in the case of which, for example, it is sought to use an expansion machine. 
       SUMMARY 
       [0010]    Against this background, the present disclosure is based on the object of providing an arrangement of auxiliary assemblies in a combustion machine, by way of which the disadvantages of conventional arrangements can be avoided. The present disclosure is based in particular on the object of providing an arrangement of auxiliary assemblies in a combustion machine, which arrangement takes up little structural space, permits a modification of a combustion machine for applications with additional auxiliary assemblies with little outlay, and permits more efficient and quieter operation of the combustion machine with less maintenance. 
         [0011]    Said objects are achieved by way of an arrangement of auxiliary assemblies having the features of the independent claim. Advantageous embodiments and uses of the present disclosure are the subject of the dependent claims, and will be discussed in more detail in the following description, in part with reference to the figures. 
         [0012]    According to general aspects of the present disclosure, an arrangement of auxiliary assemblies in a combustion machine is provided, in particular a drive arrangement of the auxiliary assemblies. The combustion machine may be an internal combustion engine in the form of a reciprocating-piston combustion machine, for example an internal combustion engine in the form of a diesel combustion machine. The combustion machine may be an internal combustion engine of a motor vehicle, in particular of a utility vehicle. The auxiliary assemblies comprise an electric machine, which is operable as a generator and preferably also as a motor, and an expansion machine. The expansion machine may be an expansion machine of a waste heat recovery system for converting waste heat of the combustion machine or of an engine braking system into utilizable energy by way of a steam circuit (waste heat recovery (WHR) circuit). 
         [0013]    The arrangement of auxiliary assemblies furthermore comprises a group of auxiliary assemblies. Said group will hereinafter be referred to as first group for better distinction from the auxiliary assemblies in their entirety. Said first group may comprise a water pump, a refrigerant compressor, a fuel pre-delivery pump, a high-pressure fuel pump, an oil pump, a steering assistance pump and further auxiliary assemblies. For example, the first group may also be formed without a refrigerant compressor. 
         [0014]    The present disclosure encompasses the general technical teaching whereby the arrangement of auxiliary assemblies is implemented without a belt drive, that is to say so as to be free from a belt drive. Therefore, no belt drive for driving the auxiliary assemblies is provided on the combustion machine. Here, the individual auxiliary assemblies of the first group are electrically driven and/or are mechanically driven by a gear drive (gearwheel mechanism) operatively connected to the combustion machine. In other words, the water pump may be electrically driven or may be mechanically driven by the gear drive. This applies correspondingly to the refrigerant compressor, the fuel pre-delivery pump, the high-pressure fuel pump, the oil pump, and the steering assistance pump. In other words, said auxiliary assemblies are either of electrified design, that is to say are electrically driveable, or are driveable without a belt drive and only by way of a gear drive of the combustion machine. The gear drive is preferably the rear gear drive of the combustion machine, that is to say the gear drive which is arranged at the gearbox-side end of the combustion machine. The electric machine and the expansion machine are operatively connected by way of the gear drive to the crankshaft of the combustion machine. The arrangement may furthermore have a further power take-off and a camshaft drive input, which can likewise be mechanically driven by the gear drive. 
         [0015]    An advantage of the arrangement according to the present disclosure of the auxiliary assemblies lies in the fact that the relatively large structural space and the component costs required for a belt drive can be saved. Furthermore, the maintenance outlay for a belt drive is eliminated. Through the electrification of at least a part of the auxiliary assemblies, the flexibility in the arrangement of the auxiliary assemblies is increased. An electrified auxiliary assembly can be arranged on the crankcase in a more flexible manner, because it does not need to be arranged at a location where a mechanical operative connection to the crankshaft is provided, for example in the form of an interface to the gear drive. Furthermore, an electrified auxiliary assembly does not need to be arranged in the immediate vicinity of the crankcase, but rather may also be arranged for example on the vehicle frame. A further advantage is that just one gear drive is sufficient to mechanically drive the non-electrified auxiliary assemblies. A further advantage is that no belt drive arranged between a fan and front face side of the combustion machine can partially block the air flow generated by the fan. 
         [0016]    The gear drive may for example be arranged on a gearbox-side end region, or on a rear end region as viewed in a direction of travel of the motor vehicle, of the combustion machine. The drive arrangement may thus be designed such that no gear drive is arranged in the region of the front face side of the combustion machine or of that face side on which the fan is provided, and only one gear drive is provided, in the region of the oppositely situated face side. This furthermore offers the advantage that the multiplicity of auxiliary assemblies are arranged in the rear region of the combustion machine and thus behind the front axle of the vehicle, and the arrangement is thus made less “nose-heavy”, which is an advantage in particular in the case of semitrailer tractors. A further advantage of just one gear drive is the lower friction torque of the internal combustion engine. 
         [0017]    It is particularly advantageous if the water pump, the refrigerant compressor and the fuel pre-delivery pump are in each case electrically driven, in particular if said auxiliary assemblies are purely electrically driven. 
         [0018]    For safety reasons, and in order to avoid engine damage, it is advantageous, by contrast, if the high-pressure fuel pump, the steering assistance pump and/or the oil pump are driven mechanically by the gear drive, wherein the oil pump and the steering assistance pump may additionally be capable of being driven by electrical and mechanical means in combination. The steering assistance pump may however also be electrified. For example, the steering assistance pump and the oil pump may be in each case electrically driven in a main delivery operating state and mechanically driven in an emergency operating state. 
         [0019]    The electrified auxiliary assemblies may in this case be supplied with electrical power via an on-board electrical system or on-board electrical subsystem, for example a 12 V, 24 V or 48 V on-board electrical system. The on-board electrical system may be an on-board electrical system of an at least partially electrically driveable vehicle. 
         [0020]    The arrangement of auxiliary assemblies may furthermore have a fan for engine cooling purposes as a further auxiliary assembly. The fan may in particular be a mechanically driven fan. In this embodiment, it is proposed that the fan be arranged coaxially with respect to the crankshaft, in particular on a front face side of the combustion machine. The front face side of the combustion machine is that face side which faces toward the front side of the vehicle, or that face side which is situated opposite the gearbox side of the combustion machine. The gearbox-side face side of the combustion machine will hereinafter also be referred to as rear face side. The fan may for example be fastened to the crankshaft or to an elongation of the crankshaft of the combustion machine, and may preferably be coupled rotationally conjointly to the crankshaft via a switching element (viscous coupling). 
         [0021]    It is particularly advantageous if the fan and the gear drive for driving the mechanically driven auxiliary assemblies are arranged on opposite end regions of the combustion machine. Here, it is not possible for a gear drive arranged between the fan and the front face side of the combustion machine, or auxiliary assemblies driven by said gear drive, to partially block the air flow generated by the fan for the purposes of cooling the combustion machine. 
         [0022]    The electrified water pump may be fastened to a front face side of the combustion machine or to a lateral wall of the crankcase. In this way, the water pump does not take up any structural space in the rear region of the combustion machine, which can be utilized for the arrangement of the mechanically driven auxiliary assemblies on the rear gear drive, and said water pump is arranged in the vicinity of the coolant-conducting components on the vehicle. Furthermore, the refrigerant compressor may be fastened fixedly with respect to the vehicle. This arrangement frees up structural space at the crankcase, enabling other auxiliary assemblies to be arranged there, and does not require any flexible lines for the transition from air-conditioning system components that are fixed with respect to the vehicle to those which are fixed with respect to the engine. 
         [0023]    In a one design variant, the electric machine which is operable as a generator and preferably also as a motor is arranged laterally on the combustion machine, in particular on a lateral wall of the crankcase or of a control case of the combustion machine. A control case refers to a case which is fastened at a face side to the crankcase and which at least partially encases the gear drive. The two lateral walls of the crankcase run between the two face surfaces and are led in a vertical direction toward an oil sump which is provided at a lower region of the crankcase. It is furthermore preferably possible for the electric machine to be arranged on a gearbox-side lateral end region of the crankcase of the combustion machine, in particular on a gearbox-side region of the lateral wall of the crankcase or control case. By way of this arrangement, it is for example possible for the electric machine to be connected to an auxiliary drive, which is operatively connected to the rear gear drive, of the combustion machine. 
         [0024]    The expression “auxiliary drive” is to be understood to mean an auxiliary drive input and/or a power take-off. The auxiliary drive may function as a power take-off for the purposes of driving one or more auxiliary assemblies. Here, a power flow is directed out of the combustion machine via the auxiliary drive. The auxiliary drive may also function as an auxiliary drive input, wherein a power flow flows to the combustion machine via the auxiliary drive. In the context of this present disclosure, an auxiliary drive thus constitutes an interface on the combustion machine, for example on the internal combustion engine, via which an auxiliary assembly or other unit is mechanically operatively connectable to the combustion machine in order, for example, to be driven by the crankshaft or in order to supply mechanical energy to the crankshaft. 
         [0025]    In a further embodiment, the arrangement comprises a compressor device for generating compressed air for a compressed-air system, for example for supplying compressed air to a compressed-air brake of the vehicle. In the case of this compressor device, at least one cylinder of the combustion machine has a controllable valve arranged in the cylinder head, by way of which valve, when it is in an open state, a connection can be produced from the combustion chamber of the at least one cylinder to a compressed-air system and compressed gas from the combustion chamber can be supplied to a compressed-air accumulator of the compressed-air system. 
         [0026]    This offers the particular advantage that, in this way, it is possible to dispense with a conventional air compressor which is driven via a power take-off of the combustion machine. The power take-off and structural space that are freed up as a result may for example be utilized for producing an operative connection between the electric machine and the crankshaft. A compressor device which extracts compressed air from a cylinder of the combustion machine in targeted fashion for the purposes of compressed-air generation is known per se from the prior art, and therefore will not be described in any more detail at this juncture. By way of example, reference is made to the documents DE 199 02 052 C2, DE 197 35 822 C1, DE 101 35 363 A1, DE 43 09 860 C1 or DE 31 18 269 A1, which describe generic compressor devices. 
         [0027]    To utilize the available structural space at the combustion machine, in particular in utility vehicles, to best possible effect, it is possible for particular auxiliary assemblies or components to be arranged in particular advantageous angle ranges on the crankcase, wherein an angle is measured as viewed in the direction of the combustion machine proceeding from a rear face side of the crankcase and upward clockwise proceeding from an angle of 0° at the bottom side of the crankcase. The following optional angle ranges of the component arrangement are illustrated in  FIG. 3 , and are described with reference to a situation in which the internal combustion engine is viewed from the rear (gearbox side). The angle is thus measured in relation to a vertical plane parallel to the crankshaft, such that the angle range from 0° to 360° spans a circle perpendicular to said vertical plane. An angle of 0° thus corresponds to an arrangement at the bottom and in the centre on the crankcase; an angle of 180° corresponds to an arrangement at the top in the centre on the crankcase; and an angle of 90° or 270° or −90° corresponds to an arrangement on the lateral wall of the crankcase. 
         [0028]    An advantageous arrangement of the electric machine which is operable as a generator and preferably also as a motor is on the lateral wall of the crankcase in an angle range from 110° to 160° or from 200° to 250°, because here, the structural space in a utility vehicle engine is not taken up by a vehicle frame or the vehicle axle, and the arrangement also does not restrict the ground clearance. 
         [0029]    An advantageous arrangement of the fuel pump is on a lateral wall of the crankcase in an angle range from 60° to 120° or from 240° to 300°. An advantageous arrangement of the oil pump lies in an angle range from −90° to 90°. An angle of −90° corresponds to 270°. An advantageous arrangement of a power take-off driven by the rear gear drive, for example for driving a hydraulic pump for body systems of the utility vehicle, is in the range from 150° to 240°. 
         [0030]    In yet another embodiment, it is possible in the context of the present disclosure for the arrangement of auxiliary assemblies to comprise a shaft which is operatively connected via the gear drive to the crankshaft of the combustion machine and which has two shaft ends, in particular two free shaft ends. The two shaft ends are designed in each case for connection to a power-outputting and/or power-receiving machine, in particular a power-outputting and/or power-receiving machine arranged outside the crankcase. In other words, the shaft has a first shaft end which is arranged so as to be connectable to a first power-outputting and/or power-receiving first machine arranged outside the crankcase. Furthermore, the shaft has a second shaft end which is arranged so as to be connectable to a power-outputting and/or power-receiving second machine arranged outside the crankcase. The two machines can thus be placed in operative connection with the shaft in alignment with one another at oppositely situated ends of the shaft. At a location arranged offset from the shaft ends in an axial direction, the shaft is operatively connected to the combustion machine. In this way, by way of the shaft, an auxiliary drive with a T-shaped power branch is provided. The operative connection of the shaft to the gear drive can thus be realized not at an end region of the shaft but at a shaft section which is spaced apart from the free ends. A shaft arranged at an auxiliary drive interface with two free ends offers the particular advantage that the auxiliary drive interface can be utilized for the arrangement of two auxiliary assemblies. It is thus possible for multiple equipment variants with regard to auxiliary assemblies to be realized flexibly, so as to save structural space, in a manner dependent on which power-outputting and/or power-receiving machine is connected to the shaft and on whether a machine of said type is connected to both free ends or only to one free end of the shaft. 
         [0031]    For example, one of the shaft ends may be connected to an expansion machine, in particular an expansion machine which is part of a waste heat recovery system for converting waste heat of the combustion machine or of an engine braking system into utilizable energy, preferably by way of a steam circuit. In the case of a waste heat recovery system of said type, a circuit medium is, with the aid of a steam circuit, for example of an ORC (Organic Rankine Cycle) process, brought to a high pressure level, evaporated in an evaporator, and superheated. Said steam is supplied to an expansion machine which converts the energy stored in the steam into utilizable energy. Downstream of the expansion machine, the vapour is liquefied again and is supplied to a feed pump. 
         [0032]    Furthermore, one of the shaft ends may be connected to an electric machine which is operable as a motor and as a generator, for example to a motor/generator of an on-board electrical system with 12 V, 24 V or 48 V rated voltage. One of the free shaft ends may also remain free, that is to say may be unequipped. Furthermore, it is possible for both shaft ends to be connected to an electric machine which is operable as a generator and preferably also as a motor. 
         [0033]    If both the expansion machine and the motor/generator are connected to the shaft, this arrangement offers the advantage that the expansion machine and the generator are operatively connectable both to one another and in each case to the internal combustion engine via the shaft, in order to permit selective electrical utilization and mechanical utilization of the energy of the expansion machine. 
         [0034]    A particular advantage of this variant thus lies in the fact that, with the shaft arranged according to the present disclosure, different equipment variants can be realized. For example, for vehicle variants which are to be equipped with a waste heat recovery system using a steam circuit, it is possible for one end of the shaft to be equipped with an expansion machine while the other end is equipped with a motor/generator. For vehicle variants which are to be provided without a waste heat recovery system, it is possible for one of the free ends to remain free, that is to say unequipped, and for the other to be equipped with the motor/generator. For applications with a high electrical demand, for example in the case of buses, it is also possible for in each case one motor/generator to be connected to each free end of the shaft. In each of the described variants, the motor/generator may, according to market demand, be selectively designed as a motor/generator with 12 V operating voltage, 24 V operating voltage, 48 V operating voltage or as a high-voltage generator (e.g. 400 V). 
         [0035]    In the context of the present disclosure, it is furthermore possible for at least one coupling or one active or passive switching to be provided in order to selectively produce or eliminate the operative connection between the machine connected to one shaft end and the machine connected to the other shaft end and/or in order to selectively produce or eliminate the operative connection of the shaft to the internal combustion engine. Alternatively, it is possible for no such coupling or no switching element to be provided, such that the shaft is operatively connected fixedly and/or non-switchably, in particular permanently, to the internal combustion engine, and/or that the machines connected to both free ends are operatively connected fixedly and/or non-switchably, in particular permanently. 
         [0036]    In still a further embodiment, the shaft is mounted in a case. In one variant of said embodiment, said case may be fastened to the crankcase, in particular to an outer side of the crankcase, or may be formed as part of the crankcase. The case may for example be fastened laterally to the outside of the crankcase. In another variant, said case may be fastened to a control case or may be formed as part of the control case. As already mentioned, the control case is a case in which a gear drive operatively connected to the internal combustion engine is arranged. The crankcase is normally open toward one face side. The control case is arranged on the face side and thus closes off the crankcase at a face side. The control case may be the rear control case, in which the rear, that is to say gearbox-side, gear drive is accommodated. Said case may furthermore be fastened both to the crankcase and to the control case. The shaft is thus fastened by way of said case to the crankcase and/or control case. The case will therefore be referred to hereinafter as intermediate case. Said variants offer the advantage that existing shapes and embodiments of the crankcase do not need to be modified for the arrangement of the shaft. Instead, a separate intermediate case is fastened to the outside of the crankcase or control case. 
         [0037]    In a further embodiment, it is however also possible for the shaft to be mounted in a case section of the crankcase. In accordance with another possibility, the shaft may be mounted in a case section of the control case. The control case may be the control case in which the rear, that is to say gearbox-side, gear drive, which is operatively connected to the combustion machine, is mounted. These variants offer the advantage that a separate intermediate case can be dispensed with. 
         [0038]    The case section and the intermediate case may, in the region of the shaft ends, have in each case one opening for the connection of a machine, which is arranged outside and/or on the crankcase, to one of the shaft ends. 
         [0039]    The intermediate case may be arranged on a lateral wall of the crankcase of the combustion machine or on the rear, that is to say gearbox-side, face side of the internal combustion engine. The two lateral walls of the crankcase run between the two face surfaces and are led in a vertical direction toward an oil sump which is provided at a lower region of the crankcase. It is furthermore preferably possible for the intermediate case to be arranged on a gearbox-side lateral end region of the crankcase of the combustion machine, in particular on a gearbox-side region of the lateral wall of the crankcase or control case. By way of this arrangement, the shaft can be connected for example to a rear gear drive, which is operatively connected to the crankshaft, of the combustion machine. 
         [0040]    Furthermore, the shaft may be mounted in the intermediate case or the case section by way of at least one radial and/or at least one axial bearing. The radial and/or axial bearings accommodate the radial and/or axial forces acting on the shaft, which forces are caused for example by the mechanical operative connection of the shaft to the gear drive. By way of such an arrangement, the normally service-life-limiting forces on the bearings of the auxiliary assemblies can be reduced or eliminated. 
         [0041]    According to a further possible aspect of the present disclosure, on opposite face sides of the intermediate case or of the case section, there may be provided in each case one fastening interface for the rotationally secured fastening of a case of the power-outputting and/or power-receiving machine. Each fastening interface is thus assigned to a shaft end. The face sides of the intermediate case are assigned to in each case one of the free shaft ends and are substantially perpendicular to the axis of rotation of the shaft. The intermediate case or the case section in which the shaft is mounted can thus perform multiple functions: the intermediate case may serve for receiving the shaft in mounted fashion and for the fastening of the machine cases of the machines operatively connected to the shaft, and for protecting the shaft against fouling and mechanical damage, and in the simultaneous design as a control case, may encase the rear gear drive and the flywheel. 
         [0042]    The shaft may be arranged such that its axis of rotation runs parallel or substantially parallel to the crankshaft axis. The free shaft ends may, for the connection to in each case one power-outputting and/or power-receiving machine, have in each case one expediently designed connection element. The connection element may for example be in the form of a connecting flange, internal teeth, external teeth, frustum, splined shaft profile, toothed shaft profile or any other shaft-hub connection. 
         [0043]    In a further variant, the shaft is arranged on a cold side of the combustion machine. This is particularly advantageous if the expansion machine is connected to a free shaft end of the shaft, because circuits for waste heat recovery (WHR circuits) normally operate with a flammable fluid, based for example on ethanol, such that, in the event of a leakage, said fluid does not pass directly to the hot side of the engine. It is likewise advantageous for the fuel pump to be arranged on the cold side of the combustion machine. 
         [0044]    As is known, combustion machines have a hot side, which during the operation of the combustion machine is at a higher temperature than the cold side. The hot side of the combustion machine is for example that side of the combustion machine at which an exhaust manifold is arranged. It is also possible for the exhaust-gas turbocharger to be arranged on the hot side. In the case of a utility vehicle, the charge-air line and the engine control unit are typically arranged on the cold side. 
         [0045]    It is furthermore possible for the arrangement to have a feed pump, a distributor valve, a bypass valve and a condenser, which are arranged on the combustion machine and which are preferably part of a waste heat recovery system for converting waste heat of the combustion machine or of an engine braking system into utilizable energy by way of a steam circuit. The feed pump, the distributor valve, the bypass valve and the condenser may be arranged on the cold side of the combustion machine, for example on the cold side on a lateral wall of the crankcase. 
         [0046]    The present disclosure also relates to a motor vehicle, in particular a utility vehicle, having an arrangement of auxiliary assemblies as described in this document. The embodiments and features of the present disclosure described above may be combined with one another in any desired manner. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0047]    Further details and advantages of the present disclosure will be described below with reference to the appended drawings, in which: 
           [0048]      FIG. 1  shows a perspective view of an arrangement of auxiliary assemblies known from the prior art on an internal combustion engine of a utility vehicle; 
           [0049]      FIG. 2  shows a perspective view of an arrangement of auxiliary assemblies on an internal combustion engine of a utility vehicle as per an exemplary embodiment of the present disclosure; 
           [0050]      FIG. 3  shows a rear-side frontal view of the internal combustion engine for the illustration of angle ranges; 
           [0051]      FIG. 4  shows a detail view of an auxiliary drive as per an embodiment of the present disclosure; and 
           [0052]      FIGS. 5A and 5B  show detail views of an auxiliary drive as per a further embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0053]    Identical or functionally equivalent elements are denoted by the same reference designations throughout the figures. 
         [0054]      FIG. 2  shows a perspective view of an arrangement  20  of auxiliary assemblies on an internal combustion engine  1  of a utility vehicle as per an exemplary embodiment of the present disclosure. The internal combustion engine  1  is in the form of a diesel combustion machine. The top side of the internal combustion engine  1  is, as in  FIG. 1 , denoted by the reference designation  5 , the front face side is denoted by the reference designation  4 , and the rear, gearbox-side face side is denoted by the reference designation  3 . The illustrated arrangement  20  of auxiliary assemblies is formed without a belt drive, that is to say so as to be free of a belt drive. The front gear drive has also been omitted in relation to the arrangement shown in  FIG. 1 . 
         [0055]    By way of example, proceeding from the known arrangement illustrated in  FIG. 1 , the omission of the belt drive has been made possible by virtue of the components that were hitherto driven by the belt drive being electrified or being relocated into the rear gear drive. The generator  24  is now driven by the rear gear drive, wherein the generator  24  may also, in comparison with the generator  14  of  FIG. 1 , be designed as a motor/generator with 12 V, 24 V or 48 V operating voltage. The generator  24  is thus operable not only as a generator but also as a motor, and for this purpose, can be supplied with electrical energy for the motor operation from an electrical energy accumulator of an on-board electrical system (in each case not illustrated). The rear gear drive, which may be designed in a manner known per se, is situated in the region of the rear face side  3  and is encased by the control case  52 , and is therefore not visible in the illustration of  FIG. 2 . 
         [0056]    The water pump  22  is, as an electrified component, configured with a 48 V operating voltage, and is arranged, fixedly with respect to the engine, on the engine front side  4 . The refrigerant compressor (not illustrated in  FIG. 2 ) is likewise designed as an electrified component with 48 V operating voltage, and can thereby be installed fixedly with respect to a frame. The refrigerant compressor installed on the vehicle frame is not illustrated in  FIG. 2 . The steering assistance pump (not illustrated in  FIG. 2 ) is likewise designed as an electrified component with 48 V operating voltage, and can thereby be installed fixedly with respect to the frame. The steering assistance pump installed in the vehicle frame is not illustrated in  FIG. 2 . By way of example, proceeding from the known arrangement illustrated in  FIG. 1 , the omission of the front gear drive in the design variant shown in  FIG. 2  is made possible by virtue of the components that were hitherto driven by the front gear drive being relocated into the rear gear drive—with the exception of the fan  7 , which is arranged coaxially and rotationally conjointly with respect to the crankshaft on a crankshaft stub  21 . The dashed line  18  indicates the central axis of the crankshaft. The high-pressure fuel pump  15  and the oil pump are driven mechanically by the rear gear drive. The oil pump may additionally be electrically driven and thus partially electrified. The rear gear drive furthermore, in a manner known per se, drives a camshaft drive input (not illustrated). The rear gear drive furthermore has a power take-off (not illustrated) for the drive of, for example, a hydraulic pump for body systems of the utility vehicle. 
         [0057]    A further feature of the arrangement  20  lies in the fact that the piston-type air impeller from  FIG. 1  has been replaced with a compressor device for generating compressed air for a compressed-air system, in the case of which at least one cylinder of the combustion machine has a controllable valve arranged in the cylinder head, by way of which valve, when it is in an open state, a connection can be produced from the combustion chamber of the at least one cylinder to a compressed-air system and compressed gas from the combustion chamber can be supplied to a compressed-air accumulator of the compressed-air system. At the auxiliary drive interface thereby freed up, there is provided a shaft  42 , which is arranged laterally on the outside of the crankcase  2  of the combustion machine, as part of an auxiliary drive  40 . On the shaft there are arranged a 48 V motor/generator  24  and an expansion machine  25 , as will be described below in even more detail in conjunction with the description of  FIG. 4 . 
         [0058]    The view in  FIG. 2  shows the cold side  31  of the combustion engine  1 , on which the engine control unit  17 , the charge-air duct  9 , a fuel module  16  and the auxiliary drive  40 , and on the latter for example a motor/generator  24  and the expansion machine  25 , are arranged. Various components for assisting the supply of fuel, such as for example a fuel filter and pressure regulator, are integrated in the fuel module  16 . On the cold side, aside from the expansion machine  25 , there are arranged further components known per se of a steam circuit, specifically a feed pump  26 , a distributor valve  27 , a bypass valve  28  and a condenser  29 , which are each fastened to the crankcase  2 . 
         [0059]      FIG. 3  shows a rear-side frontal view of the internal combustion engine for the purposes of illustrating angle ranges in which the auxiliary assemblies are arranged. For the definition of an angle range, and angle a is measured, as viewed in the direction of the combustion machine  1  from a rear face side (gearbox side) of the crankcase  2 , upward clockwise proceeding from an angle of 0° at the bottom side of the crankcase. The following optional angle ranges of the component arrangement are therefore described with reference to a situation in which the internal combustion engine is viewed from the rear (gearbox side). The angle is thus measured in relation to a vertical plane  30  parallel to the crankshaft, such that the angle range from 0° to 360° spans a circle perpendicular to said vertical plane. In the example shown, the side  31  is the cold side and the side  32  is the hot side of the internal combustion engine. 
         [0060]    The auxiliary drive  40  (with the machines motor/generator  24  and expansion machine  25  mounted thereon by way of example) is arranged on the lateral wall of the crankcase on the cold side  31  in an angle range from 110° to 160°. The fuel pump  15  is arranged on the cold side  31  in an angle range from 60° to 120°. The oil pump is arranged in the lower region of the crankcase in an angle range from −90° to 90°. If the cold and hot sides were interchanged, the motor/generator would correspondingly be arranged in an angle range from 200° to 250°, and the fuel pump would be arranged in a range from 240° to 300°, laterally on the crankcase. 
         [0061]      FIG. 4  shows a detailed view of an auxiliary drive  40  as per an embodiment of the present disclosure, wherein only the auxiliary drive  40  is illustrated in a sectional view. It has already been mentioned above that an auxiliary drive interface, on which an air compressor is arranged in the case of an internal combustion engine known from the prior art (see  FIG. 1 ), is now utilized for the arrangement of a shaft  42  which has two free shaft ends  42   a ,  42   b  which are designed in each case for connection to a power-outputting and/or power-receiving machine  24 ,  25 . The axis of rotation of the shaft  42  runs parallel to the crankshaft axis of rotation  18 . 
         [0062]    The free shaft ends  42   a ,  42   b  may, for connection to in each case one power-outputting and/or power-receiving machine  24 ,  25 , have for example a connecting flange, internal teeth, and external teeth, a frustum, a splined shaft profile, a toothed shaft profile or similar interfaces for the shaft-hub connection. In the example shown, the shaft  42  is in the form of an internally toothed shaft, such that the power-outputting and/or power-receiving machines  24 ,  25  are operatively connected in each case by way of external teeth  46  to the shaft  42 . 
         [0063]    The in-feed of power into and/or extraction of power from the shaft  42  is realized by the rear gear drive, wherein the operative connection to the crankshaft  18  is realized via a lateral opening on the crankcase  2 . Here, the shaft  42  is connected rotationally conjointly to a gearwheel  50  of the rear gear drive, wherein the gearwheel  50  can be driven by the crankshaft of the internal combustion engine  1  via intermediate gears of the rear gear drive. The gearwheel is secured to the shaft  42  by way of fastening elements  47 , for example screws. 
         [0064]    On the crankcase there is situated an intermediate case  41  which lies over the lateral opening and which is fastened to the lateral wall of the crankcase  2  on the outside of the crankcase. The intermediate case  41  is fastened to the cold side of the internal combustion engine in an angle range from 110° to 160°, as described above for the motor/generator  25 . The intermediate case  41  is fastened by way of fastening elements  43 , for example screws, to the crankcase. 
         [0065]    The shaft  42  is mounted in the intermediate case  41  by way of radial and axial bearings. On opposite face sides  48  of the intermediate case  41  there are provided fastening flanges  44 ,  45  for the rotationally secured fastening of the cases of the power-outputting and/or power-receiving means  24 ,  25 . 
         [0066]    The gearbox-side shaft end  42   b  of the shaft  42  is connected to the motor/generator  24 . The oppositely situated shaft end  42   a  of the shaft is connected to an expansion machine  25 . It is self-evidently also possible for said arrangement to be interchanged, such that the expansion machine  25  would be arranged on the gearbox-side shaft end  42   b . The expansion machine  25  is part of a waste heat recovery system for converting waste heat of the combustion machine into utilizable energy by way of a steam circuit, which furthermore comprises the feed pump  26 , the distributor valve  27 , the bypass valve  28  and the condenser  29 , as described above. 
         [0067]    The expansion machine  25  and the motor/generator  24  are operatively connected both to one another and to the crankshaft of the internal combustion engine  1  via the rear gear drive. 
         [0068]      FIGS. 5A and 5B  show detail views of an auxiliary drive  60  as per a further embodiment of the present disclosure.  FIG. 5A  shows a perspective detail view of a lateral rear end region of the combustion machine. One feature of this embodiment lies in the fact that the shaft  42  of the auxiliary drive  60  is mounted in a case section of the rear control case  52   a . For this purpose, the rear control case  52   a , which also encases the rear gear drive, is designed to be taller in relation to the control case  52  illustrated in  FIG. 2 , such that the shaft  42  can be arranged on an upper, outer case section of the control case  52   a . The flywheel case is denoted by the reference designation  56 . 
         [0069]      FIG. 5B  shows the auxiliary drive  60  in a sectional view. It has already been mentioned above that the intermediate case  41  may also be part of the rear control case  52   a  or may be the control case itself. Here, the intermediate case  41 , in which the shaft  42  is mounted, is formed as part of the control case  52   a . Thus, the mounted shaft  42  and the gearwheel  50  fastened thereto form a part of the rear gear drive. The intermediate case  41  is designed similarly to the intermediate case in  FIG. 2 . In particular, components with the same reference designations correspond to the components of  FIG. 2 , and will not be described separately. The gearwheel  50  is secured to the shaft  42  by way of screws. 
         [0070]    Even though the present disclosure has been described with reference to particular exemplary embodiments, it is self-evident to a person skilled in the art that numerous changes may be made, and equivalents used as substitutes, without departing from the scope of the present disclosure. Furthermore, numerous modifications may be made without departing from the associated scope. Consequently, the present disclosure is not intended to be restricted to the disclosed exemplary embodiments, but rather is intended to encompass all exemplary embodiments which fall within the scope of the appended patent claims. In particular, the present disclosure also claims protection for the subject matter and the features of the subclaims independently of the claims to which they refer back. 
       LIST OF REFERENCE DESIGNATIONS 
       [0000]    
       
           1  Combustion machine, in particular internal combustion engine 
           2  Crankcase 
           3  Gearbox side of the internal combustion engine 
           4  Front face side of the internal combustion engine 
           5  Topside of the internal combustion engine 
           6  Belt drive 
           6   a  Belt pulley 
           6   b  Belt 
           7  Fan 
           9  Charge-air duct 
           10  Drive arrangement 
           11  Generator 
           12  Water pump 
           13  Refrigerant compressor 
           14  Air compressor 
           15  High-pressure fuel pump 
           16  Fuel service module 
           17  Engine control unit 
           18  Centreline of the crankshaft 
           19  Oil sump 
           20  Drive arrangement 
           21  Flange 
           22  Water pump (electrified) 
           24  Motor/generator 12 V, 24 V, 48 V or high-voltage (e.g. 400 V) 
           25  Expander 
           26  Feed pump 
           27  Distributor valve 
           28  Bypass valve 
           29  Condenser 
           30  Vertical plane 
           31  Cold side of the engine 
           32  Hot side of the engine 
           40  Auxiliary drive 
           41  Intermediate case 
           42  Internally toothed shaft 
           42   a  First end 
           42   b  Second end 
           43  Fastening element 
           44  Fastening flange 
           45  Fastening flange 
           46  Teeth for the shaft-hub connection 
           47  Fastening element 
           48  Face side 
           50  Gearwheel 
           51  Control case, front 
           52  Control case, rear 
           52   a  Control case, rear 
           56  Flywheel case 
           60  Auxiliary drive