Abstract:
The invention relates to a gearbox control system for the fluidic operation of a gearbox which includes a plurality of gears that can be selected and shifted by a gearbox actuator device, and for the fluidic operation of two partial clutches of a dual clutch. The invention is characterized in that the gearbox control system includes two reversing pump actuators which are each assigned one of the partial clutches and which each have two connections to which a fluidic AND valve is connected, the latter having a tank connection as a third connection, wherein the gearbox actuator device is connected to the two reversing pump actuators via a fluidic OR valve.

Description:
BACKGROUND 
       [0001]    The invention relates to a gearbox control system for the fluidic operation of a gearbox, which comprises several gears that can be selected and shifted with the help of a gearbox actuator device, and for the fluidic operation of two partial clutches of a duplex clutch. 
         [0002]    A hydraulic device is known from the German patent publication DE 10 2008 009 653 A1 for controlling a duplex clutch gearbox of a motor vehicle, which comprises: a hydraulic energy source for supplying hydraulic energy to the hydraulic arrangement via a hydraulic medium; a pressure reservoir for storing hydraulic energy; a clutch cooling device for cooling the clutches of a duplex clutch gearbox using the hydraulic medium; clutch actuators for operating a first clutch and a second clutch, with the hydraulic energy source comprising a double-flow electric pump. A hydrostatic actuator is known from the German patent publication DE 10 2010 047 801 A1 comprising a master cylinder, having a housing and a pressure chamber inside the housing, which is axially displaceable and filled with pressure medium, comprising a piston that can be impinged with pressure, having a planetary gear with a sheath converting the rotary drive into an axial motion, with the planetary gear being driven by an electric motor. 
       SUMMARY 
       [0003]    The objective of the invention is to simplify the fluidic operation of a gearbox comprising several gears, which can be selected and switched with the help of a gearbox actuator device, and the fluidic operation of two partial clutches of a duplex clutch. 
         [0004]    The objective, to allow in a gearbox control system for the fluidic operation of a gearbox comprising several gears which can be selected and switched with the help of a gearbox actuator device, and to actuate two partial clutches of a duplex clutch in a fluidic fashion, is attained such that the gearbox control system comprises two reversible pump actuators, with one each being allocated to one of the partial clutches, which respectively show two connections to which a fluidic AND valve is connected, which has a tank connection as its third connection, with the gearbox actuator device being connected via a fluidic OR valve to the two reversible pump actuators. The reversible pump actuators preferably represent fluidic pumps that can be operated in opposite conveyance directions. The fluidic pumps particularly represent hydraulic pumps, which are operated with a hydraulic medium, such as hydraulic oil. The hydraulic pumps are preferably embodied in a positive displacement design. The hydraulic pumps may be embodied as vane pumps, geared pumps, or plunger pumps. Advantageously here electric motors are used to drive the reversible pump actuators. In a first conveyance direction the reversible pump actuators can be used for example to operate a partial clutch, particularly in order to close it. In a second conveyance direction the reversible pump actuators can be used for example to operate a gearbox actuator of the gearbox actuator device. Here, one of the gearbox actuators advantageously serves to select a gear of the gearbox. The other gearbox actuator serves advantageously for switching the selected gear. Gearbox actuators serving to execute a selection and/or shifting motion are called gear changing devices. The partial clutches of the duplex clutch can be actuated directly or indirectly. The partial clutches may be embodied as wet-running or dry-running ones. By a combination according to the invention of the two reversible pump actuators in the gearbox control system with the two AND valves and the OR valve the gearbox control system can be considerably simplified. The AND valves are also called two-pressure valves and allow in a particularly advantageous fashion different gearbox functions, independent from the direction of rotation. The AND valves are respectively allocated to the pump connections of the reversible pump actuators. With the OR valve it is easily possible that the respective reversible pump actuator, presently not involved in the operation of an allocated partial clutch, supplies the corresponding gearbox actuator of the gearbox actuator device with a feed rate and a feed pressure. 
         [0005]    A preferred exemplary embodiment of the gearbox control system is characterized in that the gearbox actuator device for implementing the switching function comprises a pivotal actuator with a reset function. In order to implement the reset function for example a return spring device may be used. The return spring device may comprise a return spring or several return springs, for example two return springs. During experiments performed within the scope of the present invention it was determined that, particularly under dynamic aspects, it proved advantageous for the pivotal actuator to comprise a reset function. 
         [0006]    Another preferred exemplary embodiment of the gearbox control is characterized in that the gearbox actuator device for implementing the selective function comprises a single-action fluid cylinder with a reset function. The reset function is provided with a return spring device, for example. The return spring device comprises for example one return spring by which the single-action acting fluid cylinder is pre-stressed into an initial position. The single-action fluid cylinder advantageously replaces a double-action fluid cylinder. This way the complexity of the required valve logistic can be considerably reduced. The return spring device for implementing the reset function acts preferably in the direction of the earth&#39;s gravity. 
         [0007]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the gearbox actuator device comprises a shift actuator and a selection actuator, which are controlled by a common valve device. The shift actuator preferably represents the above-described pivotal actuator. The selection actuator preferably represents the above-described single-action fluid cylinder. The joint valve device is for example embodied as a directional valve. The directional valve may be embodied as a longitudinal slide valve. The joint valve device is preferably pre-stressed into a central position which serves for adjusting the selection actuator. 
         [0008]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the joint valve device is embodied as a 6/3-directional valve with a central setting for adjusting the selecting actuator and two settings for adjusting the switch actuator. This way, using only one joint valve device, the selection function and the shift function of the gearbox control system can be implemented in a simple fashion. 
         [0009]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the joint valve device is embodied as a 6/5-directional valve with a central setting for adjusting the selection actuator, two settings for adjusting the shift actuator, and two intermediate settings. The intermediate settings allow in a simple fashion a passive return of a shifting rod of the gearbox actuator device into an idle position. When changing from a central position to the settings for adjusting the shift actuator the intermediate settings are crossed in a highly dynamic fashion such that a position of the gearbox actuator device selected is not left. 
         [0010]    Another particularly preferred exemplary embodiment of the gearbox control system is characterized in that the joint valve device can be operated directly by an electromagnet. This has proven advantageous with regards to the valve logistic of the joint valve device. 
         [0011]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the joint valve device can be operated via a pilot valve. The pilot valve represents for example a 2/2-directional valve embodied as a proportional valve, which is controlled electromagnetically for example. 
         [0012]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the joint valve device is embodied as a rotary slide valve. This has proven advantageous with regards to the shift dynamic of the joint valve device. 
         [0013]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the joint valve device is controlled by a rotary device. The rotary drive of the joint valve device embodied as a rotary slide valve represents for example a stepper motor. 
         [0014]    Another preferred exemplary embodiment of the gearbox control system is characterized in that the gearbox actuator device comprises a shift actuator and a selection actuator, which are controlled by two identically designed proportional-directional valve. This way the production expense can be further reduced. The identically designed proportional-directional valves are embodied for example as 4/3 directional valves and are preferably operated in an electromagnetic fashion. 
         [0015]    Another preferred exemplary embodiment of a gearbox control system is characterized in that the gearbox actuator device comprises a shift actuator and a selection actuator, which are controlled by two identically designed shift valves. This way the production expense can be further reduced. The two identically designed shift valves are embodied as 4/2-directional valves, for example. 
         [0016]    The invention perhaps also relates to a method for the fluidic actuation of a gearbox, which comprises several gears, which can be selected and shifted with the help of a gearbox actuator device and for the fluidic actuation of two partial clutches of a duplex clutch comprising one of the above-described gearbox control devices. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    Additional advantages, features, and details of the invention are discernible from the following description in which various exemplary embodiments are described in detail with reference to the drawings. Shown here are: 
           [0018]      FIG. 1  shows a simplified illustration of a gearbox control system according to the invention with two reversible pump actuators which serve for actuating a duplex clutch and a gearbox actuator device; 
           [0019]      FIGS. 2A and 2B  show a simplified illustration of a pivotal actuator with two return springs to implement a reset function; 
           [0020]      FIGS. 3A and 3B  show a similar pivotal actuator as displayed in  FIG. 2  with only one return spring for implementing the return function; 
           [0021]      FIG. 4  shows a similar illustration as  FIG. 1  comprising one pivotal actuator for implementing the shift function and a double-action fluid cylinder for implementing the selection function of the gearbox; 
           [0022]      FIG. 5  shows a detail of  FIG. 4  with a single-action fluid cylinder for implementing the selection function of the gearbox and with a joint valve device for controlling the gearbox actuator device with the two gearbox actuators; 
           [0023]      FIG. 6  shows the same illustration as  FIG. 5  with a different joint valve device; 
           [0024]      FIG. 7  shows the joint valve device of  FIG. 6  alone with control symbols; 
           [0025]      FIG. 8  shows the joint valve device of  FIG. 6  alone with one pilot valve; 
           [0026]      FIG. 9  shows an embodiment of the joint valve device of  FIG. 6  as a rotary slide valve, and 
           [0027]      FIG. 10  shows a similar illustration as in  FIG. 5  with two identically designed shift valves instead of one joint valve device. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0028]      FIG. 1  shows in a simplified fashion a gearbox control system  10  with a first reversible pump actuator  11  and a second reversible pump actuator  12 . The reversible pump actuators  11  and  12  represent fluid pumps, which can be operated in opposite conveyance directions as indicated by arrow symbols. The reversible pump actuators  11  and  12  allow in a particularly beneficial fashion the operation of a duplex clutch  20  and a gearbox actuator device  30 . 
         [0029]    The duplex clutch  20  comprises a first partial clutch  21  and a second partial clutch  22 . The first partial clutch  21  of the duplex clutch  20  can be actuated by the first reversible pump actuator  11 . The second partial clutch  22  of the duplex clutch  20  can be actuated by the second reversible pump actuator  12 . 
         [0030]    The gearbox actuator device  30  comprises a first gearbox actuator  31  and a second gearbox actuator  32 . The first gearbox actuator  31  serves to implement a selection function of the gearbox and is therefore also called the selection actuator. The second gearbox actuator  32  serves preferably for implementing a shift function of the gearbox and is therefore also called the shift actuator. A shifting rod  35  extends from the gearbox actuator device  30  in the vertical direction towards the bottom. 
         [0031]    One AND valve  41 ,  42  each is respectively allocated to the two reversible pump actuators  11 ,  12 . The AND valve  41 ,  42  is also called a two-pressure valve and has two connections by which the AND valve  41 ,  42  is connected to the respective connections of the allocated reversible pump actuators  11 ,  12 . The AND valve  41 ,  42  each comprise a tank connection as the third connection. 
         [0032]    The AND valve  41 ,  42  or the two-pressure valve allows in a simple fashion that different gearbox functions can be implemented independent from the direction of rotation of the reversible pump actuators  11 ,  12 . The gearbox actuator device  30  is coupled via an OR valve  45  to the two reversible pump actuators  11 ,  12 . This provides, among other things, the advantage that the reversible pump actuator  11 ,  12 , which at this time is not involved in the operation of a corresponding clutch  21 ,  22 , can supply the allocated gearbox actuator  32 ,  31  with a feed rate or a feed pressure. 
         [0033]    Two proportional-directional valves  51 ,  52  are switched between the OR valve  45  and the gearbox actuator device  30 . The two proportional-directional valves  51 ,  52  are embodied as 4/3 directional valves and operated electromagnetically. The two proportional-directional valves  51 ,  52  are pre-stressed in their switch position shown by a symbolically displayed spring device. The proportional-directional valve  51  is allocated to the selection actuator  31 . The proportional-directional valve  52  is allocated to the switch actuator  32 . 
         [0034]      FIGS. 2 and 3  show in a simplified version how the switch actuator  32  of  FIG. 1  may be designed. The shift actuator is embodied as a pivotal activator  60 ;  70  in  FIGS. 2 and 3 . The pivotal actuator  60 ;  70  has a reset function.  FIGS. 2A ;  3 A show the pivotal actuator  60 ;  70  in its relaxed position.  FIGS. 2B ;  3 B show the pivotal actuator  60 ;  70  in its stressed position. 
         [0035]    For implementing the reset function, the pivotal actuator  60  has two return springs  61 ,  62  shown in  FIG. 2 . The pivotal actuator  60  comprises a pivotal body  64  with a pivotal blade  65 . The pivotal blade  65  with the pivotal body  64  is mobile in reference to a fixed blade  66 , which is fastened at a fixed housing part of the pivotal actuator  60 . 
         [0036]    In  FIG. 2B  it is discernible that the return spring  61  is compressed when the pivotal body  64  with the pivotal blade  65  is rotated in the counter-clockwise direction in reference to the fixed blade. 
         [0037]    The pivotal actuator  70  shown in  FIG. 3  comprises, unlike the previous exemplary embodiment, only one return spring  71 . A pivotal body  74  is pivotal in the clockwise as well as counter-clockwise direction in a fixed housing part of the pivotal actuator  70 . Here the return spring  71  is compressed as discernible from  FIG. 3B . 
         [0038]      FIG. 4  shows that the pivotal actuator  70  implementing the shifting actuator  32  can be actuated via a pivotal blade  75  in a fluidic fashion. Using the proportional-directional valve  52  the pivotal blade  75  of the pivotal actuator  70  can be impinged with fluid pressure via the reversible pump actuator  11  either from the top or from the bottom. This way the shifting rod  35  can be appropriately rotated to implement the shift motion. 
         [0039]      FIG. 4  shows a gearbox control system  80 , which is essentially equivalent to the design of  FIG. 1 . The selection actuator  31  of the gearbox actuator device  30  is embodied as a double-action fluid cylinder  84 . The double-action fluid cylinder  84  is impinged by the reversible pump actuator  21  with fluid pressure for selecting gears via the proportional-directional valve  51 . 
         [0040]      FIGS. 5 and 6  show gearbox controls  90  in which the two proportional-directional valves  51 ,  52  are replaced by a joint valve device  100 ;  110 . In this context, the double-action fluid cylinder  84  in  FIGS. 5 and 6  is also replaced by a single-action fluid cylinder  94 . The single-action fluid cylinder  94  serves for implementing the selection function and is equipped with a return spring  95 . This way the complexity of the necessary valve logic can be considerably reduced. The return spring  95  acts in the single-action fluid cylinder  94  in the direction of the earth&#39;s gravity. 
         [0041]    The joint valve device  100  shown in  FIG. 5  represents a 6/3 directional valve with one central setting for adjusting the selection actuator  31  and two settings for adjusting the shift actuator  32 . In the central setting shown the single-action fluid cylinder  94  is released from pressure at both sides. The return spring  95  acts together with the earth&#39;s gravity upon the shift rod  35 . This way the control of the single-action fluid cylinder  94  is simplified by the bi-directionally operating hydraulic pump which drives the reversible pump actuator  12 . 
         [0042]    The joint valve device  110  shown in  FIG. 6  is embodied as a 6/5 directional valve with a central setting c, two settings a and e for adjusting the shift actuator  32 , and two intermediate settings b and d. The intermediate settings b and d serve for the passive return of the shift rod  35  into its idle position. When changing between selecting and shifting the intermediate settings b and d are passed in a highly dynamic fashion so that the adjusted selective position is not left. 
         [0043]    In  FIG. 7  it is indicated via symbols  111  and  112  that the joint valve device  110  of  FIG. 6  can be controlled directly by an electromagnet. By a symbolically indicated spring  112  the joint valve device  110  is pre-stressed in the central setting marked c in  FIG. 6 . The symbol  111  represents for example an electromagnet acting directly upon the valve logistic. 
         [0044]      FIG. 8  shows with the help of symbols  121  and  122  that the joint valve device  110  can also be controlled in a fluidic fashion by a pre-control valve  125 . The pilot valve  125  represents a proportional-directional valve with an open setting and a closed setting. The pilot valve  125  is controlled in an electromagnetic fashion and is pre-stressed in the open position shown. 
         [0045]      FIG. 9  shows that the joint valve device  110  may also be embodied as a rotary slider valve. The drive of the rotary slider valve occurs via a rotary drive, for example a stepper motor. 
         [0046]      FIG. 10  shows a gearbox control system,  150  similar to the gearbox control system  90  in  FIG. 5 . Unlike  FIG. 5 , the joint valve device ( 100  in  FIG. 5 ) in  FIG. 10  is replaced with two identically designed shift valves  151 ,  152 . 
         [0047]    The two identically designed shift valves  151 ,  152  are embodied as 4/2 directional valves. The two shift valves  151 ,  152  are operated in an electromagnetic fashion, as indicated by a respective symbol. The spring symbols indicate that the two identically designed shift valves  151 ,  152  are pre-stressed in the normal setting shown in  FIG. 10 . 
         [0048]    When the two shift valves  151 ,  152 , as shown, are in their normal setting, here the respective volume flow source, thus the respective reversible pump actuator  11 ,  12 , is connected to the single-action fluid cylinder  94 , which is also called the selection piston. 
         [0049]    When one of the two shift valves  151 ,  152  is actuated, the reversible pump actuator  11 ,  12  also called pump is respectively connected with one side of the gearbox actuator  32  to the pivotal body and/or the pivotal piston. One shift valve  151 ,  152  is provided for each direction of rotation. 
         [0050]    The gearbox control system  150  shown in  FIG. 10  is advantageous in that two relative simple, identically designed shift valves  151 ,  152  are used. Furthermore, even when one of the shift valves  151 ,  152  malfunctions, here shifting into gears can still occur in both partial transmissions. The control of selecting and shifting positions occurs via a fine control of the respective reversible pump actuators  11 ,  12 . 
       LIST OF REFERENCE CHARACTERS 
       [0000]    
       
           10  Gearbox control system 
           11  Reversible pump actuator 
           12  Reversible pump actuator 
           20  Duplex clutch 
           21  Partial clutch 
           22  Partial clutch 
           30  Gearbox actuator device 
           31  Gearbox actuator 
           32  Gearbox actuator 
           35  Shift rod 
           41  AND valve 
           42  AND valve 
           45  OR valve 
           51  Proportional-directional valve 
           52  Proportional-directional valve 
           60  Pivotal actuator 
           61  Return spring 
           62  Return spring 
           64  Pivotal body 
           65  Pivotal blade 
           66  Fixed blade 
           70  Pivotal actuator 
           71  Return spring 
           74  Pivotal body 
           75  Pivotal blade 
           80  Gearbox control system 
           84  Double-action fluid cylinder 
           90  Gearbox control system 
           94  Single-action fluid cylinder 
           95  Return spring 
           100  Joint valve device 
           110  Joint valve device 
           111  Symbol 
           112  Symbol 
           121  Symbol 
           122  Symbol 
           125  Pilot valve 
           150  Gearbox control system 
           151  Control valve 
           152  Control valve