Abstract:
A modular transmission system for the production of a plurality of modular transmission units that are modified for different applications purposes, comprising a transmission input and transmission output a power transmitting element comprising a mechanical transmission part that is arranged in a housing part and that forms with the latter a basic transmission module that includes at least one input and one output, and a control and supply unit integrated into the basic transmission module. The logic, control and supply units are arranged beneath the power transmitting element of the basic transmission module.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to a transmission modular system. 
     Transmission modular units are known in a multitude of designs for various purposes. As representatives, reference is made to the following:
         Juergen Pickard: “Planetary transmission in automatic vehicle transmissions”, Automobilindustrie 4/79, Pages 41 through 48       

     To do justice to a broad spectrum of applications, increasingly transmission modules or transmission modular systems are being developed. Such a transmission module is known from the cited state of the art, Page 47. This transmission module allows the assembly of multi-speed transmissions. The transmission module comprises thereby the individual structural components of hydrodynamic transmission elements in the form of a hydrodynamic speed/torque converter, a hydrodynamic retarder, a front-mounted range-change unit, a basic transmission module in the form of a main transmission for realization of 3 speeds and a rear transmission case. Only the hydrodynamic speed/torque converter and the main transmission for three gears and the gear control and the rear transmission case are used to realize a 3-speed transmission. With additional provision of a retarder it is arranged between the hydrodynamic speed/torque converter and the basic transmission module. For the 4-speed and 6-speed transmission a front-mounted unit is added in each case. With all of them the transmission control is arranged on the transmission case of the 3-speed main transmission. 
     While this solution does make it possible to put together different manual transmission concepts for different applications, vertically separated modular units are however required for implementation, e.g. planetary wheel planes and the retarder level. In addition, to realize the required electrical connections, for example of the electrical connection between sensors and the ECU as well as of the ECU and the actuators a multitude of plug connections and lead-in lines are to be provided in the above named modular units. The basic transmission and the sensor system cannot be inspected separately. In each case a transmission cover is always required, since in said cover a part of the sensors or other function elements is always contained. In addition, a simple interchangeability of the sensor system in the total transmission, i.e. 3-speed, 4-speed or 6-speed transmission for the hydraulic control devices as well as the sensor system is not possible without further ado, without taking the transmission module apart. 
     SUMMARY OF THE INVENTION 
     Therefore the invention is based on the object of creating a transmission module system including a majority of transmission modular units, particularly compound transmission modular units in such a way that using the same modules with little expenditure and maintaining a high degree of standardization transmission modular units can be created for a multitude of different purposes. The individual modular unit of the module itself should be mechanically convertible without having to adjust sensors, actuators, ECU, cabling. The prefabrication, i.e. the number of production steps until the final test and the performance of maintenance steps using simple personnel should be reduced. 
     The invention&#39;s solution is characterized by the features of Claim  1 . Advantageous refinements are set forth in the dependent claims. 
     With the invention&#39;s transmission module system for creating a majority of modified transmission modular units for different purposes with one transmission inlet and at least one transmission outlet a basic transmission module is common to all transmission modular units, which is identical for all transmission modular units and includes an inlet and an outlet. The basic transmission module can be combined with any transmission modular unit using additional add-on or auxiliary modules. 
     The basic transmission module comprises a mechanical transmission part, which contains the power-transferring components, for example planetary gear trains etc. and which is enclosed by a transmission case part. The mechanical transmission part with the case part form basic transmission modules, which can be locked by a locking unit comprising at least one further case part element. Along with the power-transferring components the basic transmission module further comprises at least one logic unit, a supply unit and/or additional function units, which can be addressed together as control and supply module. According to the invention the logic and control unit is integrated in the case of the basic transmission module and arranged below the power-transferring components, i.e. flanged at a specified minimum distance from the outer periphery of the power-transferring elements or on the case part of the basic transmission module. In accordance with the invention the supply unit is also assigned to the basis transmission module. Said supply unit comprises components of an operating fluid and/or lubricant and/or control supply system, further also in this regard required add-on units such as heat exchangers, cooling device, pumps, valves etc. The supply unit is also integrated in the case part of the basic transmission module underneath the power-transferring elements. 
     By logic unit the entirety of electronic control devices is understood, particularly ECU, detection devices, that is sensors and setting devices, as well as coupling with them. By control and supply unit the hydraulic control as well as components of the operating fluid and/or control and/or lubricant system are understood. 
     The hydraulic supply chain, that is the oil suction, gear pump, filter, lubrication, oil filling mechanism for the converter and retarder, heat exchanger, control blocks etc. and closed circuits can therewith be formed in the control and supply module separated from the power-transferring elements in the basic transmission module. By means of the invention&#39;s solution a spatial combination of individual components occurs according to their basic function, for one the logic and control and supply units and for another the power-conducting elements upon simultaneous formation of a horizontal borderline between these elements. Several tasks are solved by means of the arrangement. Therewith during constant execution of the basic transmission module various logic and control and supply units can be allocated to said basic transmission module. Further the basic transmission module can, by means of combination with add-on modules in the form of so-called adapter and auxiliary modules, be diversified into a multitude of transmission units. By consolidating the logic unit and the control and supply unit into one module each they can be easily randomly combined with each other. This makes it possible in simple fashion to create a model series whereby the basic transmission module can be built for itself and the control and supply module as well as the logic module can be built from stockpile and the transmission modular unit, particularly a compound transmission, can be supplemented at a potential later point in time as per application requirements with the adapter and auxiliary modules. The basic transmission module with logic and control and supply unit is additionally inspectable by itself, so that the time-consuming putting together of the whole transmission modular unit for testing purposes is no longer necessary. This feature of stand-alone inspectability is made possible by means of the separation of the power-conducting functions and non-power-conducting functions in horizontally separate units in the basic transmission module. Then only a final inspection has to be performed when the entire compound transmission is assembled according to customer specifications. 
     By basic transmission module a basic transmission is understood, which in combination with different drive units and outputs can be used for a multitude of differently designed transmission units, whereby the modifications consist only in the end piece and the drive unit, particularly in the selection of the drive elements. 
     The basic transmission module contains the power-transferring elements of the mechanical transmission part and of the case. This can be combined with corresponding control and supply modules. 
     By power-conducting elements are understood all power-transferring elements, including the elements changing the speed/torque. Included among these are for example, with transmission designs with Ravigneaux-type gear, the planetary gear trains and the switch elements necessary for realization of different gear steps. The logic module is formed by a logic unit, a control block (control-slider case, solenoid valves), the control and supply module of the hydraulic control and supply units, gear pumps and filter. The logic unit or units as a rule comprise an electronic control device. The control and supply unit comprises a hydraulic or pneumatic control device. The electronic control device comprises additionally at least one electronic controller, whereby a control unit or a unit made up of electronic and electrical components is understood by this, to which the required variables for controlling the transmission modular unit are supplied and processed inside of, and which outputs the set variables formed by the input variables corresponding to the desired drive operation. The controller comprises as a rule a majority of electric and electronic components, which are allocated to each other corresponding to the processing of the input variables to be performed and are coupled with each other. Preferably a majority of the electronic and/or electric components are jointly arranged on at least one carrier plate and are enclosed by a controller case. The electronic control device comprises, in addition to the controller, devices for recording the input variables and means for coupling the devices with the controller, further it comprises means for coupling with the corresponding setting elements for activation of the setting devices, which are allocated to the individual transmission elements of the transmission modular unit for changing the function or operation. Since the setting devices in the form of actuators can also be a component of hydraulic control devices, these means for coupling can be allocated both to the electronic control device as well as the hydraulic control device. By hydraulic control device, those hydraulic connections between the recording means of the input variables and/or the electronic control device and the setting devices are understood, which as a rule are hydraulically pressurized and the elements acting as actuators and their couplings with the setting elements. Included in this are essentially all required elements for actuating or setting the individual gear steps 
     By supply unit, those devices are understood which in the supply system provide the transmission modular unit with operating fluid for the hydrodynamic transmission part, lubricants for the mechanical transmission part and the bearings, control means for controlling the setting devices. This includes for example pump devices and filter devices integrated in the supply system. By function units, those devices are understood that are allocated to the other two units—logic unit or supply unit, but which do not assume primary functions only in these units, for example cooling devices etc. 
     From a further aspect of the invention the mechanical power-transferring transmission part, which forms the basic transmission module, comprises at least power-transfer elements, with which at lest three gear steps can be realized. For adaptation to different requirements, rear-mounted steps and/or central power take-offs and angle drives are integrable in the connection unit. For realization of a compound transmission a rear-mounted step in the form of a range-change unit is rear-mounted in the unit. This range-change unit makes possible the operation of the transmission configuration created in this way as a 3-speed, 4-speed, 5-speed and 6-speed transmission by corresponding control of the individual transmission elements. The output occurs coaxially or parallel to the transmission input shaft without additional means for realization of a central power take-off or an angle drive. 
     In a particularly advantageous design of the basic transmission module and therewith the mechanical transmission part this comprises two planetary wheel planes for realization of three gear steps, whereby both are coupled with each other and use a common element, preferably in the form of the bridge, whereby said bridge simultaneously forms the outlet of the basic transmission module. In the formation of the closing unit as a simple cover element without possibility of integrating further power-transferring elements the compound transmission is designed as a 3-speed transmission. The integration of the rear-mounted step into the closing unit, in combination with the two planetary wheel planes of the basic transmission module makes possible a very compact overall transmission modular unit for examples of application in which the operating range should be covered by at least four to six gears. 
     The means for realization of a central power take-off or of an angle drive are integrated either in the 3-speed version in the closing unit alone or in the case of a rear-mounted step being provided after said rear-mounted step in the closing unit, whereby the output of the angle drive forms the output of the transmission modular unit and therewith the transmission outlet. 
     There are a multitude of possibilities for the spatial arrangement of the individual elements in the logic module and the control and supply module. Particularly the spatial arrangement of the electronic control device and of the hydraulic control device can take place corresponding to one of the following named models:
     a) arrangement of hydraulic control device and electronic controller or electronic control device in horizontal direction side by side and considered in vertical direction, flush, i.e. without displacement;   b) arrangement of the hydraulic control device and of the electronic controller or control device in horizontal direction side by side and offset in vertical direction to each other;   c) arrangement one above the other.   

     Preferably each of the control devices or controllers has its own corresponding carrier element allocated to it, which can be connected to each other into a carrier device, so that a modular unit, comprising at least the electronic controller and the hydraulic controller, is formed. Said modular unit can in simple fashion be removed in its entirety from the control and supply module. A further option consists in arranging both—the electronic controller of the electronic control device and hydraulic control device—on a common central carrier element and likewise forming a modular unit. In both cases the entire modular unit is referred to as carrier element or carrier elements, hydraulic control device and electronic controller as control platform, which can be offered as a usable modular unit. 
     From a further aspect of the invention, the arrangement of logic units, control and supply units and function units takes place considered in fitting position at a height which lies in the area of the height of the operating fluid, lubricant or control fluid sump in the transmission. From a further aspect of the invention the electronic control device has a case allocated to it, which preferably is constructed as sealed against hydraulic fluid, for example oil and/or another fluid. The controller can then be directly arranged in the operating fluid, control fluid and/or lubricant sump of the transmission modular unit. As a result of this the possibility additionally exists of exposing the electrical and electronic components of the controller to at least indirect cooling by means of the operating fluid in the operating fluid, control fluid and/or lubricant sump or by means of the cooling devices, heat exchangers etc. arranged there. The oiltight design of the case causes, however, for realization of the electrical bond between the controller and the sensors of the control device required for recording the variables at least indirectly characterizing the current driving condition and/or wishes of the driver and/or further marginal conditions and the actuators controlled by means of the control device for activation of the individual elements of the transmission modular unit, for example for realization of the gear change of the switch elements or the setting devices of the switch elements and/or for presetting of input variables by means of a overriding control or regulation device, a correspondingly designed execution or preferably only docking, for example to a transmission socket at the oil pan. 
     The arrangement of the controller in fitting position in the lower area of the transmission modular unit and the provision of a corresponding case make it possible to arrange the sensors for recording the individual variables at least indirectly describing the operation of the individual elements of the transmission modular unit at a specified time likewise in the area underneath the transmission center line which corresponds to the axis of rotation and therewith makes it possible to design the entire control device including the sensor system and actuator system relatively compactly. The arrangement in the operating fluid, control fluid and/or lubricant sump, which as a rule is collected in a so-called oil pan, which is formed by the bottom part of the transmission case, in the present case of the case element of the body transmission, makes it possible additionally to remove the control device complete with the related control hydraulics, the actuator system for operation of the individual switch elements and the sensors as well as the supply devices, elements, filters etc. which as a rule are arranged on the case of the oil pan in simple fashion and test them separately as a whole of operating ability possibly additionally under specified predefinable conditions. 
     The creation of the transmission module occurs using the basic transmission unit by combination with different drive units for example in the form of a hydrodynamic transmission part and the possibility of different design of the closing units. The single transmission modular units thus ordered differ from each other with constant mechanical transmission part solely in the design of the drive units and the closing units, whereby this is essentially for the application case and the requirements attached to the application case as well as possibly the logic and control and supply units. 
     The power-transferring transmission part, which also forms the basic transmission module, as well as the control and supply module combined with it form thereby a basic transmission for a transmission component, whereby the individual units—basic transmission module and logic module as well as control and supply module—can be manufactured separately and only have to combined with each other as modules. Particularly the easy exchangeability made possible by means of the horizontal separation between the power-conducting parts in the basic transmission and the control and supply units is thereby of advantage. For example, the individual components of the basic transmission module and logic as well as control and supply units can be selected as the smallest common unit. Proceeding from the basic transmission module different drive units can be provided for different purposes and further also different outputs, for example central power take-offs or angle drives. This is realized by means of combination with the further adaptation and auxiliary modules the drive unit and closing element. The case of the drive unit and closing element together with the case part element of the basic transmission module form the total transmission case. From a further aspect of the invention it is also possible to integrate the drive unit in the basic transmission module proceeding from a basic transmission module, that is particularly for the case in which the same drive element or the same configuration of the drive unit can be used. In this case the adaptation to the most different output circumstances takes place via the corresponding design of the closing element, particularly as a rear-mounted range-change unit with or in the form of a central power take-off or angle drive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The solution of the invention is explained in the following in detail using figures. The figures show the following: 
         FIG. 1  illustrates in diagrammatically simplified representation the basic principle of the utilization of a basic transmission module designed according to the invention in a compound transmission unit with a drive unit in the form a converter, the basic transmission module and logic, control and supply module in compact design; 
         FIG. 2  illustrates an advantageous development of a basic transmission module with logic, control and supply module for use in a platform concept in accordance with the invention; 
         FIGS. 3   a  through  3   e  illustrates individual transmission designs with identical structure with regard to drive unit and basic transmission component and different closing units; 
         FIGS. 4   a  through  4   d  show in diagrammatically simplified representation examples of application for transmission modular units as per  FIG. 3   a;    
         FIGS. 5   a  through  5   d  show in diagrammatically simplified representation examples of application for a transmission modular unit as per  FIG. 3   b;    
         FIGS. 6   a  through  6   c  show in diagrammatically simplified representation designs of drive systems with transmission modular units as per  FIGS. 3   c  and  3   d;    
         FIG. 7  illustrates in diagramatically simplified representation an example of application of a transmission modular unit as per  FIG. 3   e.    
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates in diagramatically simplified representation the basic principle of the invention&#39;s transmission module system in the form of a basic transmission module  5  in compact fashion in a complete transmission modular unit  1 . In the case of the transmission modular units it is a matter preferably of compound transmissions  2 , which comprise at least one mechanical transmission part  3 , which is coupled with a drive unit  51  in the form of a hydrodynamic transmission part or a hydrostatic transmission part  4 . The basic version of the combination  50  out of basic transmission module  5  and drive unit  51  in the form of a hydrodynamic transmission part  4  represents a version for realization of at least three gear steps. The related mechanical transmission parts  3  and the hydrodynamic transmission part  4  or the hydrostatic transmission part are combined into one structural unit out of a basic transmission module  5  and drive unit  51 . The basic transmission module  5  has an outlet  6  which can be coupled with the power-transferring elements, which can be combined with the basic transmission module  5  for ensuring further additional functions. As per the invention all logic units and control and supply units  9  as well as the related function units  10  for example in the form of a logic and control module or supply module  53  are integrated in the basic transmission module  5 . These form together with the basic transmission module  5  a platform transmission  50 . The arrangement of the logic units  8 , the control and supply units  9  as well as the function units  10  allocated to them takes place underneath the power-transferring elements of the mechanical transmission part  3 , i.e. essentially underneath the extension of a theoretical connection axis by means of the inlet and outlet  6  of the basic transmission module and at a distance to the outer periphery of the power-transferring elements, which is designated here with  11 . The minimum dimension for the distance to be observed is to be selected in such a way that the operation of the power-transferring elements of the basic transmission module  5  is not impaired. The logic units  8  comprise thereby function elements for control and regulation tasks. Belonging to the logic or control units  8  for example are a control device  12  allocated to the transmission modular unit  1  or the compound transmission  2 , including at least one controller  13 , whereby the term controller  13  is essentially to be understood as a control device, for example ECU, while the term control device  12  considers both the inlets and outlets of the controller  13  as well as the coupling options with sensors and actuators as well as the connection leads. The control device  12  comprises at least an electronic control device  15 . The hydraulic control device  14  is a component of the control and supply unit  9 . The electronic control device  15  comprises thereby an electronic controller  16 , which is understood as a unit of electrical and electronic components, which supplies the required variables for controlling the transmission modular unit  1 , particularly the compound transmission  2 , and are processed in said transmission modular unit, and which outputs the set variables formed from the input variables corresponding to the desired drive operation. The electronic controller  16  comprises as a rule a majority of electrical and electronic components which are allocated to each other and coupled with one another corresponding to the processing of the input variables to be performed. Preferably a majority of the electrical and/or electronic components are jointly arranged on at least one carrier plate  17  and are preferably enclosed by a controller case  18 . Thereby the possibility exists that the carrier plate  17  is completely integrated in the controller case  18  or forms at least a partial wall area of the controller case  18 . Along with the controller  16  the electronic control device  15  comprises devices for recording the initial variables and means for coupling the devices with the controller  16 , further means for coupling with the corresponding setting elements for activating the setting devices, which are allocated to individual transmission elements of the transmission modular unit, particularly of the mechanical transmission part  3  and the hydrodynamic transmission part  4  for changing the function and/or operation. Since the setting devices in the form of actuators can also be components of the hydraulic control device  14 , the means for coupling can then be allocated both to the electronic as well as also the hydraulic control device  14 . By hydraulic control device  14  are understood the hydraulic connections between the recording means of an initial variable and/or the electronic control device  15  and the setting devices, which as a rule can be hydraulically pressurized and the elements acting as actuators and their coupling with the setting devices. Included in this term are essentially all elements necessary to activate for activation or setting of the individual gear steps on transmission modular unit  1  or on the compound transmission  2 . 
     The control and supply unit  9  further comprises the elements which for example are used for preparation and supplying of pressure media to the setting devices of the transmission elements. Among these are for example pump devices  19  as well as connection leads for conduction of the pressure media. Subsumed under function units  10  are those elements which are allocated to the individual units logic unit  8  or supply unit  9  and fulfill an additional function that is not primarily only underlying these units, or have a separate function. Among these are included for example filter devices  20 , heat exchangers  21 . 
     According to the invention the arrangement of the elements of the logic unit  8 , the control and supply unit  9  as well as function units  10  occurs separately from the power-transferring elements of the transmission modular unit, i.e. the mechanical and hydraulic transmission part, whereby the arrangement preferably occurs underneath the axis of symmetry S G  of the power-transferring elements or always at a specified distance a to the outer periphery  11  of the power-transferring elements. 
     The basic transmission module  5  thus formed, which is designed for realization of at least three gear steps, thereby forms a separate basic transmission modular unit, which is inspectable as a separate modular unit, whereby the case part  23  does not necessarily have to be sealed off. The basic principle of the solution of the invention lies thereby in the spatial combination of the individual according to their basic function, particularly the combination of the power-transferring elements as well as the logic and supply units upon simultaneous formation of a horizontal border line between them. Preferably the arrangement of the logic unit  8 , of the control and supply unit  9  and of the function unit  10  occurs in fitting position at the height of or underneath the oil volume level. In addition to the advantage of an increased reliability, since the number and length of the cable connections required for electrical coupling by means of integration of the electronic control device  15  in the case  22  of the transmission modular unit compared to conventional solutions is considerably lower, this solution offers the possibility of individual synchronization of the control device to each transmission modular unit, without having to perform a reprogramming of the controller in the exchange of essential power-transferring elements of the total transmission modular unit  1  and therewith a change of the configuration of the transmission modular unit. The unique allocation of transmission modular unit and electronic control device makes possible a simplification of the production logistics. The structural integration of the electronic control device  15  and the hydraulic control device  14  makes it possible to create an inspectable unit of control device, control hydraulics, actuator system and sensor system of the transmission modular unit  1 , whereby the control device  15  is already adaptable to the transmission-specific tolerances during the inspection operation. The arrangement underneath the transmission axis of symmetry or underneath or next to the exterior circumference of the power-transferring elements offers the advantage that the electronic and hydraulic control devices are easily accessible and exchangeable. 
     Regarding the spatial arrangement of hydraulic control device  14  and electronic control device  15  there are a multitude of possibilities not described in detail here. The following are conceivable
     a) an arrangement of hydraulic control device  14  and electronic control device  15  or at least of electronic controller  16  in horizontal direction side by side and considered in vertical direction flush, i.e. without displacement;   b) an arrangement of hydraulic control device  14  and electronic controller  16  or of electronic control device  15  in horizontal direction side by side and in vertical direction offset to each other;   c) arrangement considered in horizontal direction one above the other.   

     Preferably each of the control devices or controllers—electronic controller  16  or electronic control device  15  and hydraulic control device  14 , not shown here, however, has a corresponding carrier element allocated to it, which can be connected to each other into a carrier device, so that a modular unit, comprising at least the electronic controller  16  and the hydraulic control device  14 , can be formed. Said modular unit can in simple fashion be removed in its entirety from the transmission modular unit. 
       FIG. 2  illustrates in diagrammatically simplified representation a potential of a basic transmission module  5 . 2 . Said basic transmission module comprises a mechanical transmission part  3 . 2 , which is enclosed by a case  23 . The case  23  is designed so that it holds at least the mechanical transmission part  3 . 2 , preferably however additionally also the add-on modules  55  in the form of a hydraulic or hydrodynamic transmission part  4 , not shown here. The mechanical transmission part  3 . 2  comprises in the represented case two planetary gear trains, a first planetary gear train  24  and a second planetary gear train  25 . Each planetary gear train comprises a sun gear, the planetary gear train  24  has sun gear  24 . 1 , planetary gear train  25  has sun gear  25 . 1 , planetary gears and an internal ring gear. For planetary gear train  24  the planetary gears are designated  24 . 2  and the internal ring gear is designated as  24 . 3 . In analogy this designation was also performed for planetary gear  25 . 2  and internal ring gear  25 . 3  of planetary gear train  25 . Planetary gears  24 . 2  and  25 . 2  of the individual planetary gear trains  24  and  25  are mechanically coupled with each other, by means of a joint bridge  26 . The bridge  26  forms the outlet  6 . 2  of the basic transmission module  5 . 2  and simultaneously of the resulting platform transmission  50 . 2 . Both sun gears are connected by means of a shaft with the transmission input not shown here of transmission modular unit  1 . The shafts are designated here by  27  and  28 . Shafts  27  and  28  form the inlets of the basic transmission module  5 . 2 . Said shafts are at least indirectly coupled with the transmission inlet of the total transmission modular unit or support themselves in corresponding manner on an element of the total transmission modular unit. Further integrated in basic transmission module  5 . 2  underneath the power-transferring elements, particularly planetary gear trains  24  and  25 , are logic unit  8 . 2 , the control and supply unit  9 . 2  and the function units  10 . 2 , here all combined into a so-called control and supply module  45 , which can be detachably connected with the case of the basic transmission module  5 . 2 . 
       FIGS. 3   a  through  3   e  illustration the realization of different total transmission modular units  1 . 3   a  through  1 . 3   e  from a basic transmission module as per  FIG. 2  and logic units  8  and control and supply units  9 , preferably combined into control and supply module  53 . Each of the transmission modular units  1 . 3   a  through  1 . 3   e  comprises a basic transmission module  5 . 2 , which preferably is equally constructed and dimensioned for all the different transmission modular units  1 . 3   a  through  1 . 3   e , for example as shown in  FIG. 2 . Further transmission modular units  1 . 3   a  through  1 . 3   e  have an add-on module in the form of a drive unit  52 . 3  in the form of a hydrodynamic transmission part  4 . 3   a  through  4 . 3   e , which comprises a hydrodynamic speed/torque converter  29 , whereby the hydrodynamic speed/torque converter preferably is also uniformly designed with regard to the structure and the dimensioning. For adaptation to different requirements however, there is also the possibility of allocating different add-on modules to the basic transmission module  5 . 3  in the form of speed/torque converter  29 . To guarantee the adaptation of the transmission modular units  1 . 3   a  through  1 . 3   e  to different marginal conditions, depending on the requirements, an additional add-on module  56  comprising rear-mounted steps  30 . 3   a  through  30 . 3   e  and/or output units  31  is allocated. 
     From a further aspect of the invention as per the developments in  FIGS. 3   a  through  3   e  the control and supply module  53  formed from the control and supply units  9  and logic units  8  can be identically designed for the transmission modules  5  of different transmission units  1  and an adaptation to different requirements can take place only by exchange of the add-on modules  55  in the form of drive units  52  and/or of add-on modules in the form of the closing elements. In this case the platform transmission  50  forms the foundation for the structure of a transmission module from the combination of basic transmission module  5  and control and supply module  53 . 
     From a further aspect of the invention the platform transmission  50  can also be designed in such a way that it comprises the basic transmission module  5 . 2 , as well as a control and supply module  53 , whereby this module is not necessarily to be understood as a modular unit, but rather as a multitude of individual elements that are more or less connected to each other. A case or case part  54  then also belongs to the basic transmission module, said case which can be designed in such a way that it can also hold a drive unit. The drive unit can be exchangeable at random. The only deciding factor is that the requirements be present on the part of the case  54  to also hold add-on module  55  in the form of the drive unit  53 . 
     In the embodiment shown in  FIG. 3   a  the total transmission modular unit  1 . 3   a  comprises along with platform transmission  50  from a basic transmission module  5 . 2  and integrated control and supply module  45  a hydrodynamic speed and torque converter  29  as drive unit  52  and an add-on module  56  rear-mounted step  30 . 3   a  in the form of a range-change unit comprising a planetary gear train  32 , whose input  33  is connected with the output  6  of basic transmission module  5 . The input is formed for example by bridge  32 . 4  of the planetary gear train  32 . The outlet  34  of the transmission modular unit  1 . 3   a  is formed for example by a spur gear  35  arranged concentrically to the transmission axis of symmetry SR or to the central axis of planetary gear train  32  and a shaft coupled with said spur gear, whereby the spur gear  35  meshes with the output  34  of the planetary gear train  32 . In this case the planetary gear train  32  acts as a rear-mounted range-change unit  30 . 3   a , which by means of internal ring gear  32 . 3  and the spur gear  35  arranged concentrically to said internal ring gear formed spur gear train or the shaft coupled with this as  37 . 3   a  of the transmission modular unit  1 . 3  The integration of the rear-mounted range-change unit  30 . 3   a  and the output  37 . 3   a  takes place in a separate case part  38 , which is combined with case  23  of the basic transmission module  5 . 3  into total transmission case  22 . The case part  38  is free of logic units  8 , supply units  9  and function units  10 , which are combined in the control and supply module  45  and in the basic transmission module  5 . 2  or its case  23 . 
       FIG. 3   b  illustrates a further possible design of a total transmission modular unit  1 . 3   b  from a platform transmission  50  made of basic transmission module  5 . 2  and an add-on module  55  in the form of a hydrodynamic transmission part  4 . 3   b , in which the transmission outlet  39  is formed by an angle drive  40 . The basic structure of hydrodynamic transmission part  4 . 3   b  and basic transmission module  5 . 2  corresponds to the one described in  FIG. 3   a  or  2 . With this transmission it is, depending on the control of the individual switch elements, a case of a model by means of which at least six speeds can be realized. For this purpose a rear-mounted step is also provided here, which with regard to its structure is identical to the one described in  FIG. 30.3   b . The same drawing references are used for the same elements. This is also designed as a planetary gear train whose inlet  33  is formed by bridge  32 . 4  of the planetary gear train and whose output or outlet is formed by internal ring gear  32 . 3 . The outlet  36  is coupled with the angle drive  40 . The angle drive  40  is designed as a bevel gear step comprising a first bevel gear  41 , which is locked with the outlet  36  of the rear-mounted step  30 . 3   b  or  34  of planetary gear train  32 , particularly with the internal ring gear  32 . 3  and which preferably forms a structural unit, and a second bevel gear  42 , which is locked with the shaft  37 . 3   b , which simultaneously forms the outlet of transmission modular unit  1 . 3   a . Here too the rear-mounted step  30 . 3   b  and the angle drive  40  are integrated in a case part, here it is case part  43 . The case part  43  forms the total transmission case  22  together with case  23  of the basic transmission module  5 . 2 . 
       FIG. 3  illustrates a development of a total transmission structural unit  1 . 3   c  with a basic transmission module  5 . 2 , an add-on transmission module in the form of a hydrodynamic transmission part  4 . 3   c  and an add-on transmission module  56  in the form of a rear-mounted range-change unit  30 . 3   c , comprising a planetary gear train  32  similar to the models shown in  FIGS. 3   a  and  3   b , whereby however the drive  37 . 3   c  of the transmission modular unit  1 . 3   c  is coaxially arranged to the transmission inlet of the transmission modular unit  1 . 3   c . In this case the output occurs without additional resources directly by the internal ring gear  32 . 3  of the planetary gear train  32 , whereby the internal ring gear  32 . 3  for this purpose is coupled with a shaft, transmission outlet shaft  44 . The transmission configuration shown in  FIG. 3   c  can be executed corresponding to the control of the individual transmission elements in dependency on the control program as a 4-speed, 5-speed or 6-speed version with coaxial output  37 . 3   c  for transmission inlet shaft  46 . 
     As opposed to that,  FIG. 3   d  illustrates a total transmission modular unit  1 . 3   d , which is designed as a 3-speed version and consists only of mechanical transmission parts of the basic transmission module  5 . 2  and the add-on module  55  in the form of drive unit  51 , comprising a hydrodynamic transmission part  4 . 3   d . The outlet  6  of the basic transmission module  5  forms simultaneously the output  37 . 3   d  or outlet of the total transmission modular unit  1 . 3   d  and is coaxially arranged to the transmission inlet shaft  46 . 
       FIG. 3   e  illustrates a model of a total transmission modular unit  1 . 3   e , comprising a basic transmission module  5 . 2 , a hydrodynamic transmission part  4 . 3   e  and a further second add-on component  56 , comprising a rear-mounted step  30 . 3   e , which is preferably designed similar to the one in  FIGS. 3   a  through  3   c . The outlet  34  of the planetary gear train  32 , which is formed by the tubular shaft  32 . 3 , simultaneously acts as a first output  37 . 31   e , whereby the output  37 . 31   e  is coaxially arranged to transmission inlet shaft  46 , while a further second output  37 . 32   e  can be realized by a coupled with the internal ring gear  32 . 3 , in the simplest case an additional spur gear  47 . Here too rear-mounted step  30 . 3   e  and the corresponding outputs  37 . 31   e ,  37 . 32   e  are arranged in a separate case part in the form of a closing part  43 , which can be combined with the case  23  of the basic transmission module  5 . 2  into a structural unit, the total transmission case  22 . 
       FIGS. 3   a  through  3   e  illustrate possible designs of individual total transmission modular units of a transmission module with a high degree of standardization on the basis of the transmission modular system. 
     Further design options are also conceivable, and lie in the discretion of the responsible person skilled in the art. The designs portrayed in  FIGS. 3   a  through  3   e  represent preferred designs which stand out regarding the function to be realized through a high degree of standardization, low component requirements as well as building space requirements. Different application possibilities result from these transmission structural units, which are reproduced in  FIGS. 4 through 7 . 
     The transmission configuration as per  FIG. 3   a  is used for the following designs on the vehicle shown in  FIGS. 4   a  through  4   d . The design of a total transmission modular unit  1 . 3   a  as per  FIG. 3   a  with central power take-off, i.e. arrangement of the output concentrically to the center line of the planetary gear train  32  of the rear-mounted step, is used preferably for transverse arrangements of the drive machine  48 . 4   a ,  48 . 4   b ,  48 . 4   c  in the vehicle. The total transmission modular unit  1 . 3   a  is coaxially arranged to the drive machine  48 . 4   a . The output occurs as per the designs in  FIGS. 4   a  through  4   d  in vertical direction for example on an axis or at a gear  49 . The axle drive can either take place central to the central power take-off or offset. The coupling between the central power take-off and the axle occurs either via a bevel gear set, a tripod propeller shaft and a standard axle with vertical drive or via a spur gear train, a spur gear differential with homogeneous propeller shafts or tripod propeller shafts. 
       FIG. 4   c  illustrates a design of a drive system for bus drive with a transversely mounted drive machine  48 . 4   c , a total transmission modular unit  1 . 3   a , whereby the central power take-off occurs vertically, the axle however is driven centrally via a lateral output, for example a transmission with spur gears. 
       FIG. 4   d  illustrates a design similar to  FIG. 4   c , whereby however a portal axle is used as an axle. 
       FIGS. 5   a  through  5   d  illustrate designs of drive systems for bus drives, in which the drive machine  48 . 5   a  through  48 . 5   d  is also in transverse arrangement. The transmission modular unit  1 . 3   b  is coaxially arranged to the drive machine  48 . 5   a  through  48 . 5   d . The drive on the axle occurs by means of central coupling of the output of the total transmission modular unit  1 . 3   b . For this purpose angle drives of 60 and 65° are used.  FIG. 5   a  illustrates a design for right-hand traffic, while  FIG. 5   b  makes possible a design for use in countries with left-hand traffic.  FIGS. 5   c  and  5   d  illustrate similar designs for right-handed and left-handed traffic, whereby however the axle is designed as a portal axle and the low-floor drive occurs transversely and not centrally, but rather offset on the axle. 
       FIGS. 6   a  through  6   c  illustrate applications for total transmission designs as per  FIGS. 3   c  and  3   d .  FIG. 6   a  shows in diagramatically simplified representation a standard bus drive, in which the arrangement of drive machine  48 . 6   a  as well as total transmission modular unit  1 . 3   c  or  1 . 3   d  occurs longitudinally to the direction of travel. The axle drive occurs essentially in the area of the center of the axle, whereby the output  37  also is coupled in longitudinal direction of the axle.  FIG. 6   b  illustrates a design as per  FIG. 6   a , whereby however the axle drive does not occur centrally, but rather offset for a portal axle. Both designs are suitable for right-handed traffic, whereby the design as per  FIG. 6   a  is also suitable for left-handed traffic. To achieve a suitability for left-handed traffic with designs with portal axle an application as per  FIG. 6   c  is required on the portal axle. This clearly shows that the connection to the portal axle always takes place on the side of the axle which is the furthest away from the doors of the vehicle. 
       FIG. 7  illustrates a possible application of a total transmission design as per  FIG. 3   d  using a lateral view of a vehicle. This is especially suitable for all-wheel drive, whereby the arrangement of the combustion power machine  48 . 7  and the transmission modular unit occurs in longitudinal direction of the vehicle and the drive is realized centrally on the axles. 
     LIST OF REFERENCE SYMBOLS  
     
       
         
               
               
             
           
               
                   
               
             
             
               
                 1, 1.2, 1.3 
                 Total transmission modular unit 
               
               
                 1.3b, 1.3c, 1.3d 
               
               
                 2 
                 Compound transmission 
               
               
                 3, 3.2, 3.3a 
                 Mechanical transmission part 
               
               
                 3.3b, 3.3c, 3.3d 
               
               
                 4, 4.2, 4.3a, 
                 Hydrodynamic transmission part 
               
               
                 4.3b, 4.3c, 4.3d 
               
               
                 5, 5.2 
                 Basic transmission component 
               
               
                 6, 6.2 
                 Outlet 
               
               
                 7, 7.2 
                 Transmission outlet 
               
               
                 8, 8.2 
                 Logic unit 
               
               
                 9, 9.2 
                 Control and supply unit 
               
               
                 10, 10.2 
                 Function unit 
               
               
                 11 
                 Outer periphery of the power-transferring elements 
               
               
                 12 
                 Control device 
               
               
                 13 
                 Controller 
               
               
                 14 
                 Hydraulic control device 
               
               
                 15 
                 Electronic control device 
               
               
                 16 
                 Electronic controller 
               
               
                 17 
                 Carrier plate 
               
               
                 18 
                 Controller case 
               
               
                 19 
                 Pump device 
               
               
                 20 
                 Filter device 
               
               
                 21 
                 Heat exchanger 
               
               
                 22 
                 Transmission case 
               
               
                 23 
                 Case of the body transmission 
               
               
                 24 
                 Planetary gear train 
               
               
                 24.1 
                 Sun gear 
               
               
                 24.2 
                 Planetary gears 
               
               
                 24.3 
                 Internal ring gear 
               
               
                 25 
                 Planetary gear train 
               
               
                 25.1 
                 Sun gear 
               
               
                 25.2 
                 Planetary gears 
               
               
                 25.3 
                 Internal ring gear 
               
               
                 26 
                 Bridge 
               
               
                 27 
                 Shaft 
               
               
                 28 
                 Shaft 
               
               
                 29 
                 Hydrodynamic speed/torque converter 
               
               
                 30.3a, 30.3b, 
                 Rear-mounted step 
               
               
                 30.3c, 30.3d 
               
               
                 31 
                 Output unit 
               
               
                 32 
                 Planetary gear train 
               
               
                 32.1 
                 Sun gear 
               
               
                 32.2 
                 Planetary gears 
               
               
                 32.3 
                 Internal ring gear 
               
               
                 32.4 
                 Bridge 
               
               
                 33 
                 Inlet of the planetary gear train 32 
               
               
                 34 
                 Outlet of the planetary gear train 32 
               
               
                 35 
                 Spur gear 
               
               
                 36 
                 Output 
               
               
                 37 
                 Output 
               
               
                 38 
                 Case part 
               
               
                 39 
                 Transmission outlet 
               
               
                 40 
                 Angle drive 
               
               
                 41 
                 First bevel gear 
               
               
                 42 
                 Second bevel gear 
               
               
                 43 
                 Closing part, case part 
               
               
                 44 
                 Case outlet shaft 
               
               
                 45 
                 Control and supply module 
               
               
                 46 
                 Transmission inlet 
               
               
                 47 
                 Spur gear 
               
               
                 48.4a, 48.4b 
                 Drive machine 
               
               
                 48.4c, 48.4d 
               
               
                 48.5a, 48.5b 
               
               
                 48.5c, 48.5d 
               
               
                 48.6a, 48.6b 
               
               
                 48.6c, 48.6d 
               
               
                 50 
                 Platform transmission 
               
               
                 51 
                 Drive unit 
               
               
                 52 
                 Basic transmission 
               
               
                 53 
                 Logic an control or supply module 
               
               
                 54 
                 Case part 
               
               
                 55, 56 
                 Add-on module 
               
               
                 S G   
                 Transmission axis of symmetry