DE10060699A1 - Change wheel gear for e.g. variable speed gears in motor vehicles etc. has additional device for moment/RPM conversion to relief coupling unit on intake side - Google Patents

Abstract

The transmission has an output shaft and two input shafts, and an automatic coupling unit. It also has at least one additional device for positive/non-positive moment and/or RPM conversion to relieve the coupling unit on the intake side. The additional device consists of an additional pair of toothed gears, and is operated by an existing actuator unit. The additional gears have a higher ratio than the original gears, approx. higher by 5-60% esp. 2-25% than the ratio of the first gear.

Description

The present invention relates to a transmission, in particular a Gear change gear. Such transmissions are generally used for torque and Speed conversion z. B. used in motor vehicles. There are a number of Gear pairs contain, of which a first gear, such as gear, rotatably is connected to a shaft, a second gear, such as idler gear, is by means of a Clutch can be connected to another shaft. On the input side is a Coupling unit arranged. Such gears can also be operated automatically become. The clutches for connecting the idler gears to a shaft and / or the clutch unit on the input side are then actuated operated.

The invention further relates to a method for operating such a system Gearbox.

The advantages of such automated actuation are obvious. However is the driver does not, as with a manually operated transmission, directly on  Switching process involved, which is why it is slightly insensitive to critical States of the transmission, in particular that arranged on the input side Coupling unit can be, so that it is much more pronounced may occur. This problem should first be examined using the example of a Dual clutch transmission are described: The between the drive motor and Transmission clutch unit is designed as a double clutch. about a first clutch disk, a first countershaft can be driven in the transmission, carries the gears that belong to the odd gears. About a second A second countershaft is drivable in the transmission, the clutch disc Gears that belong to the straight gears. When starting the first clutch is closed when 1st gear is engaged, the second clutch remains open so that the second countershaft is torque-free. For one Shifting is engaged in 2nd gear, the first clutch is opened and the second closed; the further upshifts or reverse the downshifts.

In driving conditions, such as starting, in particular with a load and / or on an incline or stop on an incline or crawl or similar Conditions where the vehicle speed is below that at closed clutch unit and the lowest possible Drive motor speed is or at which a defined torque is at a standstill Vehicle must be applied, the clutch unit, in particular thermal, considerably stressed.

This problem arises in all transmissions in which such driving conditions for example, due to the driver's lack of reference to the  Operations in the transmission and on the clutch due to an automated Activity, pronounced can occur, which is a very large burden on the Coupling unit can have permanent damage, it must remedy.

Various options have been proposed, in particular to reduce the thermal load on the clutch unit. So is for example in German published patent application DE 33 07 943 A1 Disc spring described, the particularly large ventilation wing for generating a Has cooling air flow. The German patent DE 31 35 998 C2 and German Offenlegungsschrift DE 31 35 995 A1 disclose clutches in which heat dissipation achieved by means of a coolant conveyed by a pump becomes. Furthermore, the German design DE 12 94 228 B is a clutch become known, which among other things by an optimal cooling of the parts exposed to thermal effects.

All of these solutions aim at a heat input already in the coupling to achieve rapid or improved heat dissipation.

The object of the present invention is the clutch unit, in particular thermal, already relieved by a reduced heat input. Farther an optimized gearbox should be made available to the driver offers increased comfort and improved handling. It should  continue to create a process through which in various Driving situations as quickly and comfortably as possible, for example without Traction interruption changed between the required gear ratios can be.

This object is achieved in that at least additionally another device for torque and / or speed conversion for relief of the clutch unit on the input side is present.

The preferred developments of the invention are the subject of Subclaims.

In the present application, as is generally the case, the translation level of the transmission with the highest gear ratio referred to as first gear. The Gears two, three etc. indicate translation levels with the second highest translation, with the third highest translation etc. If that Transmission an additional gear ratio to relieve the input Has clutch unit, the names are first, second, third Maintain gear etc. even if the additional gear ratio is higher than the first gear is translated. The translation levels are each through Gear pairs formed.  

The wide torque and / or speed conversion advantageously takes place in a form-fitting manner and / or non-positively and it will be used to operate this additional device for torque and / or speed conversion already in the gearbox and on Clutch unit used existing controls. For example, these are actuators for engaging and disengaging the Clutch disks of the clutch assembly formed clutches as well Actuators for selecting and switching gear ratios in the Gear trains.

In an advantageous embodiment, the clutch assembly relieves that for positive torque and / or speed conversion additional pair of gears that have a higher gear ratio than 1st gear has, is present. The clutch torque is one of the Gear ratio difference between this additional pair of gears and the 1st Corresponding gear reduced.

A preferred embodiment already describes the utilization existing gear pairs in combination to achieve a higher overall gear ratio, than that of 1st gear. Below is the usage understood several translation levels in succession, so that their Multiply translations. Depending on the structure of the Gearbox, for connecting the gear pairs at least one additional gear or another clutch to connect the shafts on which the Gears of the gear ratios are arranged, which are used in combination are intended for power transmission with each other.  

The translation of the additional translation level or the Total gear ratio of the gear pairs used in combination expediently about 5-60%, in particular 20-25%, higher than that First gear translation. Such a translation higher than the first Gait can also be referred to as crawling, starting or mountain gear.

In a further advantageous embodiment, the non-positive Relief of the input-side clutch unit an additional, under Slip operable clutch proposed. For better heat dissipation it is useful to design this additional clutch as a wet clutch. It However, there may also be exemplary embodiments in which it is advantageous if the additional clutch is designed as a dry clutch.

For example, the additional clutch that can be operated under slip is like this carried out that transmits a limited constant moment. If necessary is then an additional moment on the input side clutch unit initiated or an excess torque reduced or the output speed increased or decreased.

However, it can also be advantageous if the additional clutch is adjustable is carried out so that in any case an adapted, preferably complete Relief of the input-side clutch unit can take place.

If the gearbox is a gearbox as described above an additional one for positive torque and / or speed conversion Translation level or translation levels are used in combination,  are additional in a preferred embodiment Translation level or the translation levels used in combination and the gear ratio to which you want to switch without traction interruption, assigned to different clutch discs.

In the case of a transmission in a preferred embodiment, the additional ones Translation level or the translation levels used in combination and the first gear assigned to different clutch disks, being it is useful if also the additional translation level or in Combination used gear ratios, the second gear, the Reverse gear and possibly further gear ratios of the same Clutch disc are assigned.

According to a further preferred embodiment with a transmission or without an additional translation level or the one used in combination Gear ratios are different for the first gear and the second gear Clutch disks assigned where it is useful if - if it is a gearbox with additional gear ratio or the in Combination of used translation levels acts - the additional Translation level or the translation levels used in combination, the first gear, reverse gear and, if necessary, further gear ratios are assigned to the same clutch disc.  

In a further preferred embodiment, the additional Translation level or the translation levels used in combination and the reverse gear are assigned to different clutch disks.

According to yet another preferred embodiment, the first gear and the reverse gear assigned to different clutch plates, wherein the gearbox with or without additional gear ratio or in combination translation stages used can be carried out. It is very useful even if the second gear and the reverse gear are different Clutch disks are assigned.

A particular advantage is achieved, especially when it comes to the Embodiments described each gear train a reverse gear is assignable.

In all of the exemplary embodiments described, the assignment makes certain Gear ratios to different clutch discs achieved that this can be inserted at the same time and by pressing the Clutch discs of the clutch unit in alternation Switching between these gear ratios without traction is possible.  

The invention also relates to a method for operating a transmission provided in particular according to the above exemplary embodiments, at which is advantageously the drive via the first or the second clutch disc of the input-side clutch unit takes place, the first to start Gear, the second gear or the reverse gear, is used.

Particularly preferred is an embodiment of the method in which Starting off or when the vehicle speed is below a certain Value is the additional gear ratio or in a first start-up mode the gear ratios used in combination and the first gear are inserted at the same time, so that a continuous switching between them is possible.

Also an execution of the procedure in which to start or when the Vehicle speed is below a certain value, in a first further start mode, the first gear and the second gear engaged at the same time are, so that continuous switching between them is possible expedient.

It is very beneficial when starting off or when the vehicle speed is below a certain value, in a second further start-up mode the additional gear ratio and reverse gear engaged at the same time are, so that a continuous switching between them is possible.  

Furthermore, a special advantage is achieved when starting or when the Vehicle speed is below a certain value, in a third further start mode of the first gear and the reverse gear are engaged, see above that continuous switching between them is possible.

It is expedient to start or when the vehicle speed is below a certain value, in a fourth further starting mode the second gear and the reverse gear are engaged, so that a continuous Switching between them is possible.

An embodiment of the method in which the third is particularly preferred further start mode from the second further start mode or the fourth further start-up mode out of the third further start-up mode can be selected automatically if in the second or in the third further starting mode several short successive changes of approach and / or one Winter mode and / or spinning of the driven wheels can be detected.

According to a preferred development of the method, the reverse gear is Can be disengaged if a certain distance is being driven was covered and / or a certain speed is exceeded.  

In a preferred embodiment of the method, the additional gear ratio used if an increased drive torque required and / or a, in particular thermal, relief of the input side Coupling unit is necessary and / or a crawl operation is desired. Furthermore, the gear ratio with the second highest is used for starting Ratio used if a reduced drive torque, for example because of low grip, is desired and / or a larger one, in particular thermal load on the input-side clutch unit is permitted can be.

An increased starting torque can occur, for example, when starting on a slope and / or when starting with an increased load. When using the the clutch unit on the input side becomes an additional gear ratio relieved, so that, for example, the temperature input there is lower. As Creep operation can be described as a driving condition in which the Vehicle speed below the speed when closed input side clutch unit and lowest possible Drive motor speed is. Such a crawl would be without the additional ones Gear ratio only when the clutch assembly on the input side slips possible.

The exemplary embodiment also enables a downshift in FIG the additional translation level. The additional translation stage cannot  can only be used for starting, but it can also be used when driving from a another translation stage.

If it is in the further moment and / or Speed conversion to relieve the clutch unit on the input side an additional gear with a higher gear than 1st gear Translation, it is particularly advantageous to use this gear level To assign the clutch disc, the even gears 2, 4 and possibly 6th assigned.

For example, 1st gear can be used as a standard starting gear, if it is a higher gear Starting torque and / or relief on the input side Clutch unit is required to use the additional gear Find. With certain starting processes, for example when starting up smooth road surface where a lower starting torque is required or is required and / or a higher (thermal) load on the input side Coupling unit can be approved, it may be advantageous to the 2nd Select gear as starting gear.

Furthermore, the invention advantageously enables a downshift in the additional gear from one of the lower gear, especially from 1st gear. This may be necessary, for example, when And-go traffic on slopes.  

The invention is in no way limited to the exemplary embodiments mentioned, Rather, it can be used in all transmissions where driving conditions such as for example starting off, in particular with a load and / or on an incline or stop on a slope or crawl or similar conditions where the vehicle speed below that when closed Clutch unit and the lowest possible engine speed is or included to which a defined moment must be applied when the vehicle is stationary, for example, due to the driver's lack of reference to the Operations in the transmission and on the clutch due to an automated Activity, which can be very pronounced, are used. Also one analogous application of the invention for the reverse gear of a vehicle can be beneficial. The reverse gear was shown in the present figures and Descriptions are not shown for reasons of clarity.

An exemplary embodiment of the invention is described below with reference to Drawings explained in more detail. Show it:

Fig. 1 skeleton diagram of a twin clutch transmission countershaft design with by taking advantage of existing gear pairs realized further device for torque and / or speed conversion,

FIG. 2a torque flow in 1st gear,

Fig. 2b torque flow in 2nd gear,

Fig. 2c torque flow when using the further device for torque and / or speed conversion,

Fig. 3a skeleton diagram of a twin clutch transmission of countershaft design in which the further device for torque and / or speed conversion is implemented as a coupling with a limited constant torque,

FIG. 3b skeleton diagram of a twin clutch transmission of countershaft design in which the further device for torque and / or speed conversion is implemented as a clutch with adjustable torque,

Fig. 4 skeleton diagram of a twin clutch transmission of countershaft design in which the further device for torque and / or speed conversion is carried out as an additional gear stage,

FIG. 5a is a flow chart for gear selection, part 1,

Fig. 5b is a flowchart for gear selection, Part 2,

Fig. 6 skeleton diagram of a twin clutch transmission, with available by combination and an additional transmission stage unrealized Another device for torque and / or speed conversion,

Fig. 7 is a flowchart for the start-up mode.

In Fig. 1 a double clutch transmission with realized by utilizing existing gear pairs further device for torque and / or speed conversion is shown as a skeleton 100th A shaft 101 is driven via a drive motor and is connected to the housing 111 of a clutch assembly 110 designed as a double clutch. The clutch housing 111 can be connected to a first clutch disk 112 and / or to a second clutch disk 113 . Both clutch disks 112 , 113 can contain devices for vibration damping 114 , 115 .

With the first clutch disk 112 , a first transmission input shaft 102 can be driven, which drives a first countershaft 104 via a gear pair 120 , which is formed by the gear wheels 120 a and 120 b. The first countershaft 104 carries the idler gears 121 a, 122 a and 123 a of the gear pairs 121 , 122 and 123 , which form the gears 1, 3 and 5. The idler gears 121 a, 122 a and 123 a can be rotatably connected to the countershaft 104 by means of clutches 143 and 144 .

With the second clutch disc 113 , a second transmission input shaft 103 can be driven, which drives a second countershaft 105 via a gear pair 130 , which is formed by the gear wheels 130 a and 130 b. The second countershaft 105 carries the gear wheels 131 a and 132 a, and the idler gear 133 a of the gear pairs 131 , 132 and 133 , which form the gears 2, 4 and 6. The gear wheels 131 a and 132 a are rotatably connected to the countershaft 105 , the idler gear 133 a can be connected to it by means of a clutch 142 .

The idler gears 131 b and 132 b of gears 2 and 4, as well as the gear gears 121 b, 122 b, 123 b and 133 b of gears 1, 3, 5 and 6 are arranged on the output shaft 106 , the gear wheels 121 b, 122 b, 123 b and 133 b are rotatably connected to the output shaft 106 and the idler gears 131 b and 132 b can be connected to it in a rotationally fixed manner via a clutch 141 .

There is also a clutch 140 for connecting the second input shaft 103 to the first countershaft 104 or the first input shaft 102 to the second countershaft 105 .

The clutches 140 , 141 , 142 , 143 and 144 and the clutch unit 110 with the two clutch plates 112 and 113 can be actuated automatically. The clutches 141 , 142 , 143 and 144 connect the idler gears 121 a, 131 b, 122 a, 132 b, 123 a and 133 a to the shafts 104 , 105 and 106 via a sliding sleeve and a coupling part connected to the shaft in a rotationally fixed manner . The clutch 140 connects the gear wheel 120 a with the idler gear 131 b via a sliding sleeve. Clutches 140 , 141 , 142 , 143 and 144 may include elements for speed synchronization.

To start in 1st gear, the idler gear 121 a is connected in a rotationally fixed manner by means of the clutch 143 to the countershaft 104 , the clutch 144 being open and the drive shaft 101 being connected to the first input shaft 102 via the first clutch disk 112 of the clutch assembly 110 . For an upshift to the 2nd gear, the idler gear 131 b is connected in a rotationally fixed manner by means of the clutch 141 to the output shaft 106 , the clutch 142 being open; by releasing the first clutch plate 112 from the clutch housing 111 , the drive shaft 101 is separated from the first input shaft 102 and the drive shaft 101 is connected to the second input shaft 103 via the second clutch 113 . For all further upshifts or downshifts, the procedure is such that the torque flow is diverted from one countershaft to the other, the respective shift clutches being closed or opened in each case.

Fig. 2a shows the torque flow 2150 in 1st gear. The clutch 2143 connects the idler gear 2121 a of the 1st gear rotatably with the first countershaft 2104 , via the clutch disc 2112 the drive shaft 2101 is connected to the first input shaft 2102 . The torque of the drive shaft 2101 - converted by the gear pairs 2120 and 2121 - is transmitted to the output shaft 2106 .

Fig. 2b shows the torque flow in 2250 in 2nd gear. The clutch 2241 connects the idler gear 2231 b of the second gear rotatably to the first output shaft 2206 , via the clutch disc 2213 the drive shaft 2201 is connected to the second input shaft 2203 . The torque of the drive shaft 2201 - converted by the gear pairs 2230 and 2231 - is transmitted to the output shaft 2206 .

Fig. 2c shows the torque flow 2350 in using the additional device for torque and / or speed conversion. Of particular importance here is the clutch 2340 , which connects the gear 2320 a with the idler gear 2331 b, that is, the second input shaft 2303 to the first countershaft 2305 , via a sliding sleeve. It is thus possible to form both the gear ratio of a gear on the first countershaft 2304 , for example of the 1st gear, formed by the gear pair 2321 with the clutch 2343 closed, and that of a gear on the second countershaft 2305 , for example of the 2nd gear by the gear pair 2331 with the clutch 2341 closed, to be used in combination and to achieve a higher overall ratio than that of the 1st gear. The load on the clutch unit is reduced in accordance with the increased gear ratio compared to 1st gear.

In Fig. 3a, the embodiment of the further device for torque and / or speed conversion is illustrated as operated with constant slip coupling 3150. In the same way as described for the previous figures, starting and switching between the gears takes place by redirecting the torque flow between the countershafts 3104 and 3105 , even if in this illustration the distribution of the gear and idler gears of the gear pairs 3131 , 3132 , 3133 is related the countershafts and the output shaft is different.

In the phases to be classified as critical, such as starting, in particular with a load and / or on an incline or stopping on an incline or creep or comparable conditions, in which the vehicle speed is lower than that with the clutch unit closed and the lowest possible drive motor speed or in which a defined one Moment must be applied when the vehicle is stationary, the drive shaft 301 is connected to the second input shaft 3103 via the second clutch disc 3113 . The torque flow takes place via the gearwheel pair 3130 , the second countershaft 3105 , the clutch 3150 and the gearwheel pair 3152 on the output shaft 3106 . The constant slippage on the clutch 3150 relieves the clutch unit 3110 . If a higher torque is required at the output, an adjustable torque can additionally be introduced via the first clutch disc 3112 , the first input shaft 3102 , the gear pair 3120 , the first countershaft 3104 and the gear pair 3121 . If the torque at the output is too great, it can be reduced by loosening the second clutch disc 3113 .

In Fig. 3b, the execution of the further device for torque and / or speed conversion is illustrated as operated with adjustable slip clutch 3250th The advantage here is that the torque required on the output shaft 3206 can be set precisely on the clutch 3250 . The torque flow takes place from the drive shaft 3201 via the second clutch disc 3213 of the clutch unit 3210 to the second input shaft 3203 . The output shaft 3206 is driven via the gear pair 3230 , the second countershaft 3205 , the clutch 3250 and the gear pair 3152 . The input-side clutch unit 3210 can therefore be completely relieved in the present case.

The clutch 3150 , 3250 described in FIGS . 3a and 3b as a further device for torque and / or speed conversion is designed in the present exemplary embodiment as a wet clutch and can advantageously be accommodated in the transmission housing.

Fig. 4 shows a skeleton representation of a double clutch transmission, in which the further device for torque and / or speed conversion is designed as an additional gear stage on the countershaft of the even gears, such as 2nd, 4th and optionally 6th gear.

Coming from the drive motor via the input shaft 401 , the drive torque is transmitted to the countershafts 404 and / or 405 by means of clutch disks 413 and / or 414 . On the countershaft 404 , gear wheels of an additional gear 420 , which is higher than the first gear and can be referred to as a so-called creeper gear, the second gear 423 and the fourth gear 425 are arranged. The countershaft 405 carries gears of the 1st gear 421 , the 3rd gear 424 and the 5th gear 426 . The output takes place via the output shaft 406 .

According to the principle of the double clutch transmission, the present arrangement enables a smooth, low-traction interruption or even free change between the gears arranged on the countershaft 404 and the gears arranged on the countershaft 405 .

Driving is advantageous with the exemplary embodiment described, in particular a start, possible, which meets both the demand for a increased or decreased drive torque as well as the (thermal) load of the clutch unit arranged on the input side is sufficient.

The inventive ideas are not limited to the present one Embodiment, but are also applicable to other gear structures, for example on structures in which the drive of the countershafts by means of  Clutch plates in any combination is possible, especially the drive a first and / or a second countershaft by means of a first and / or a second clutch disc, transferable.

FIGS. 5a and 5b show a flow chart for gear selection. In the event of a start-up process, see block 5105 , if the vehicle has a special mode for winter operation in which a lower drive torque is desired, particularly when starting, block 5106 is checked to determine whether this winter operation is switched on. If this is not the case, the crawler gear 420 is engaged on the countershaft 404 and the 1st gear 421 on the countershaft 405 , block 5107 , which corresponds to normal operation, see 5108, otherwise the 2nd gear 423 and are on the countershaft 404 1st gear 421 engaged on countershaft 405 , see 5109.

Depending on the clutch temperature as a representative signal for the (thermal) load of the clutch assembly arranged on the input side, the countershaft 404 or 405 is connected to the input shaft 401 via the clutch disk 414 or 415 , block 5110 and thus in creeper gear 420 , see block 5111 , or in 1st gear 421 , see block 5112 , started. If a wheel slip is detected when starting in creeper gear 420 , for example by comparing the number of driven and non-driven wheels and / or by means of a corresponding gradient of one or more wheel speeds, see 5117, a change to 1st gear 421 is made , block 5112 . Likewise, when starting in 1st gear 421 , block 5112 , in the event of wheel slip, block 5115 , it is possible to change to 2nd gear 423 accordingly, see block 5113 . When starting in 1st gear 421 and ascertaining a hill start, block 5114 , for example due to a large required drive torque, a change is made to creeper gear 420 . If the vehicle was started in crawl gear 420 , see 5111, driving continues until the shift point for 1st gear is reached, block 5116 and then changed to this, see block 5118 .

The transition from FIG. 5a to FIG. 5b takes place from 5101 to 5201, from 5102 to 5202 and from 5103 to 5203, these transitions are to be regarded as connections. When driving in 1st gear, block 5205 , it is checked whether there is a so-called creep, see block 5206 . If this is the case, there is a change to the creeper gear, see 5207 with subsequent wheel slip test, block 5209 . If wheel slip is detected, shifting back to 1st gear takes place, block 5212 , otherwise 1st gear is only selected again when the shift point is reached, block 5208 . If continuous creep is not found in block 5206 , a wheel slip test is subsequently carried out, block 5210 . If slip is detected, a change is made directly to 2nd gear, block 5213 , otherwise only when the shift point is reached, block 5211 . The same can be done for the further drive in 2nd gear, block 5214 .

In Fig. 6 is a skeleton diagram of a twin clutch transmission, with available by combination and an additional transmission stage unrealized Another device for torque and / or speed conversion.

The drive torque can be transmitted to one of the two input shafts 602 and / or 603 via one of the two clutch plates 612 and / or 613 of the clutch assembly 610 on the input side, which is designed here as a double clutch. Gears are arranged on the two shafts 602 and 603 which, together with other gears, form transmission stages. The gear ratios can be divided into two groups A and B, each of which can be assigned to a clutch disc 602 or 603 . In the present example, the translation stage labeled 1 is the highest translated, corresponding to 1st gear, translation stage 2 is the second highest translation, corresponding to 2nd gear, and so on. With R a gear ratio with a reversal of direction, such as reverse gear, is referred to; the reversal of the direction of rotation is achieved, for example, by means of an additional gear 630 .

The gear ratios 1 to 5 form a sequence with regard to their translations, the gear ratios being arranged so that successive gear ratios can be assigned to different clutch plates 612 or 613 , respectively. In the present case, gears 1, 3 and 5 form group B and are to be assigned to clutch disc 612 , gears 2, 4 and R form group A, which is assigned to clutch disc 613 .

The clutch disks 612 and 613 of the clutch assembly 610 on the input side enable the torque flow to be switched continuously from one group A of gear ratios to the other group B.

Relief of the clutch unit on the input side is made possible by the clutch 620 , by means of which the two input shafts 602 and 603 can be connected via the shaft 604 . If the torque flows through the clutch disc 612 , the gears 1, 3 and 5 are not engaged, the clutch 620 is closed and either gear 2 or gear 4 is engaged, the translation of the gear ratio 625 , formed by the gears 625 a and 625 b and either the translation of the 2nd or 4th gear is used in series, so that the translations of these gear ratios multiply, so a significantly higher translation is achieved than in the 1st gear.

In all the described embodiments, in which one - however realized - crawl gear is provided with a particularly high gear ratio, can 1st gear compared to 1st gear in a transmission without creeper be translated correspondingly longer, because in a version with a creeper in 1st gear no such high starting performance has to be required.

Fig. 7 shows a flowchart 700 for start-up mode. When starting up or when the vehicle speed is below a certain value, see block 710 , a start-up mode is displayed in blocks 703 , 704 , 705 , 706 and 707 according to the set speed level, such as forward or reverse speed level, and possibly based on other criteria , selected. In the case of a desired forward drive, a first start-up mode, see block 703 , or a first further start-up mode, block 704 , can be selected. In the first start-up mode, a crawl gear, however it is implemented, and 1st gear are engaged at the same time; this start-up mode is very advantageous, for example, if the clutch unit on the input side is to be relieved and / or an increased starting torque is required, especially when starting on a slope and / or under load; In a first further starting mode, 1st and 2nd gear are engaged at the same time, this starting mode can be selected if a less high starting torque is necessary and / or the clutch unit on the input side does not have to be relieved as much.

In the case of a desired reverse travel, a second, a third or a fourth further starting mode can be selected. In the second further starting mode, see block 705 , the creeper gear and reverse gear are engaged at the same time, in the third further starting mode, see block 706 , 1st and reverse gear are engaged at the same time, and in the fourth further starting mode, see block 707 , there are also 2nd and reverse gear inserted. It is advantageous if a switch is made from the second additional starting mode, in which a very high starting torque is available, to the third additional starting mode if a condition is recognized that requires a reduced starting torque - such as a switched-on winter mode, a rocking motion, So quick changes between driving forwards and backwards or spinning the wheels - or a higher load can be permitted on the input-side clutch unit. It is also possible to switch from the third to the fourth further starting mode on the basis of the criteria just described.

It can also be advantageous to provide several differently geared reverse gears in the transmission. In this case, it is favorable to combine reverse gears with a lower gear ratio with forward gears with a lower gear ratio, ie to engage at the same time. All of the starting modes just mentioned combine the advantage of a low-traction or even-free switching between the two simultaneously engaged gear stages by means of the clutch unit on the input side. In particular, in the starting modes in which a reverse gear is engaged, this remains engaged until a certain driving distance has been covered in the forward direction and / or a certain driving speed has been reached in the forward direction, see blocks 708 , 709 and 710 . For example, even when maneuvering, rapid changes of direction without switching with regard to the engaged gear stages are only possible using the input-side clutch unit.

In all starting modes, the two gears engaged at the same time, if the Invention for example in a dual clutch transmission for use should come, different clutch disks are assigned so that by connecting one clutch disc and loosening the other Clutch disc a continuous switching of the torque flow between the two gears, in the case of an engaged forward gear and an engaged reverse gear to switch the direction of travel.

All described functions that the simultaneous insertion of gear ratios assigned to different clutches and a Actuation of the clutch unit on the input side for one Powershift operation in the transition alternate, in particular Control strategies in which no further facility for torque and / or Speed conversion is necessary, are expressly also on gearboxes without  further device for torque and / or speed conversion, such as creeper, applicable.

In particular, the application of the invention to a transmission brings particular Advantages if the clutch to be relieved is a dry friction clutch.

According to a further inventive idea, it is proposed in To provide an electric machine in connection with the present transmission, whose rotor, for example with a freely rotatable flywheel, which is advantageous by means of at least one clutch from the drive unit such as an internal combustion engine and can be isolated from the power take-off unit like gears for swing use, is connected, or forms this, so that by means of these arrangements Hybrid drives are possible.

According to this embodiment, the transmission enables extensive use the electric machine, for example as a starter unit for the internal combustion engine, Power generator, partial drive, full drive and as a unit for conversion kinetic energy into electrical energy or into kinetic rotational energy Use of the rotor as a flywheel when decelerating Vehicle with decoupled internal combustion engine (recuperation).

Furthermore, the present invention relates to the applications DE 198 59 458 A1 and DE 199 45 474 A1, the content of which expressly relates to the content of the disclosure belongs to the present application. For the sake of clarity, the  present application on the representation of the automated operation of the input-side clutch unit, the shift clutches and the additional Device for torque and / or speed conversion is dispensed with.

The claims submitted with the application are drafted strikes without prejudice for obtaining further patent protection. The The applicant reserves the right to add more, so far only in the description and / or To claim drawings disclosed combination of features.

Relationships used in subclaims point to the others Training the subject of the main claim by the features of respective subclaim; they are not a waiver of attainment an independent, objective protection for the combinations of features to understand the related subclaims.

Since the subjects of the subclaims with regard to the prior art on Reserves the right to make its own independent inventions Applicant before becoming the subject of independent claims or To make divisional declarations. You can continue to work independently Inventions contain one of the objects of the previous Have independent claims independent design.  

The exemplary embodiments are not to be understood as a restriction of the invention. Rather, there are numerous changes within the scope of the present disclosure and modifications possible, in particular such variants, elements and com combinations and / or materials, for example by combination or Modification of individual in connection with that in the general description and embodiments and the claims described and in the Features or elements contained in drawings or process steps for the specialist with a view to solving the problem can be found and by Combinable characteristics for a new object or for a new process steps or process step sequences lead, also insofar as they are manufacturing, testing and Concern working procedures.

Claims (37)

1.Gearbox with an output shaft and two input shafts, with which two transmission strands comprising parallel transmission stages are formed, which can be driven by connecting them to a drive shaft by means of a clutch disk of a clutch assembly which can be actuated automatically on the transmission input side by means of a first actuating device, with two clutch disks, the A plurality of the clutch ratios which are successive in terms of their gear ratio are assigned to different clutch disks, characterized in that at least one further device for torque and / or speed conversion is provided to relieve the clutch unit on the input side. 2. Transmission in particular according to claim 1, characterized in that the further torque and / or speed conversion form-fitting and / or done non-positively.   3. Transmission in particular according to claim 1 and / or 2, characterized in that to actuate the further device for torque and / or Speed conversion already used an existing actuator becomes. 4. Transmission in particular according to claim 1 and / or 2, characterized in that for positive torque and / or speed conversion additional gear pair is present. 5. Transmission in particular according to claim 4, characterized in that the additional gear pair has a higher gear ratio than that Gear pair of the first gear. 6. Transmission in particular according to claim 5, characterized in that the Ratio of the additional gear pair about 5-60%, especially 20- 25%, is higher than the first gear ratio. 7. Transmission in particular according to claim 1 and / or 2, characterized in that for positive torque and / or speed conversion About settlement levels can be used in combination.   8. Transmission in particular according to claim 7, characterized in that the Combined gear ratios already exist in the transmission Are translation levels. 9. Transmission in particular according to claim 7 and / or 8, characterized in that at least two translation stages are combined with one another in such a way that that a total gear ratio is greater than that of the first gear. 10. Transmission in particular according to at least one of claims 7-9, in which Gear ratios can be switched by means of clutches, thereby characterized in that at least one for combining the translation stages further clutch is used. 11. Transmission in particular according to claim 10, characterized in that the at least one more clutch the shafts on which the gears the translation levels are arranged, used in combination be connected to each other for power transmission. 12. Transmission in particular according to claim 1 and / or 2, characterized in that a non-positive torque and / or speed conversion there is an additional clutch that can be operated under slip.   13. Transmission in particular according to claim 12, characterized in that the Clutch is a wet clutch. 14. Transmission in particular according to claim 12, characterized in that the Clutch transmits a limited constant torque. 15. A transmission in particular according to claim 14, characterized in that an opening or closing of the input side Clutch unit, if necessary, initiated an additional moment or an excess torque can be reduced or the output speed can be increased or decreased. 16. Transmission in particular according to claim 12, characterized in that the Clutch transmits an adjustable torque. 17. Transmission in particular according to at least one of claims 1-11, characterized characterized in that the additional translation level or in Combination used translation levels and the translation level, too to be switched without interruption in tractive power, various Clutch disks are assigned.   18. Gearbox with one output shaft and two input shafts, two of which parallel transmission stages comprehensive gear trains are formed which are drivable, each by means of a clutch disc arranged on the transmission input side by means of a first Actuating device with automatically actuated clutch unit two clutch disks can be connected to a drive shaft, wherein Gear ratios that can be switched without interruption in tractive power are assigned to different clutch disks. 19. Transmission in particular according to claim 17, characterized in that the additional translation level or those used in combination Gear ratios and first gear different clutch discs assigned. 20. Transmission in particular according to claim 19, characterized in that the additional translation level or those used in combination Gear ratios, second gear, reverse gear as well if necessary, further gear ratios of the same clutch disc assigned. 21. Transmission in particular according to claim 17 or 18, characterized in that the first gear and the second gear different clutch plates assigned.   22. Transmission in particular according to claim 21, characterized in that the additional translation level or those used in combination Gear ratios, the first gear, the reverse gear and if necessary further gear ratios are assigned to the same clutch disc. 23. Transmission in particular according to claim 17, characterized in that the additional translation level or those used in combination Gear ratios and reverse gear different Clutch disks are assigned. 24. Transmission in particular according to claim 17 or 18, characterized in that the first gear and the reverse gear are different Clutch disks are assigned. 25. Transmission in particular according to claim 17 or 18, characterized in that the second gear and the reverse gear are different Clutch disks are assigned. 26. Transmission in particular according to claim 17 or 18, characterized in that a reverse gear can be assigned to each gear train.   27. Method for operating a transmission, in particular according to at least one of claims 19-26, characterized in that the drive via the first or the second clutch plate of the clutch unit on the input side takes place, the first gear, the second gear or the Reverse gear, is used. 28. A method for operating a transmission, in particular according to claim 19 or 20, characterized in that for starting or when the Vehicle speed is below a certain value in one first start-up mode, the additional gear ratio or in combination used gear ratios and the first gear engaged at the same time are, so that a continuous switching between them is possible. 29. A method of operating a transmission, in particular according to claim 21 or 22, characterized in that for starting or when the Vehicle speed is below a certain value in one first further starting mode, the first gear and the second gear simultaneously are inserted so that a continuous switching between them is possible. 30. A method of operating a transmission, in particular according to claim 23, characterized in that for starting or when the Vehicle speed is below a certain value in one  second additional start-up mode the additional gear ratio and Reverse gear are engaged at the same time, so that a continuous Switching between them is possible. 31. A method for operating a transmission, in particular according to claim 24, characterized in that for starting or when the Vehicle speed is below a certain value in one third gear, the first gear and reverse gear engaged are, so that a continuous switching between them is possible. 32. Method for operating a transmission, in particular according to claim 25, characterized in that for starting or when the Vehicle speed is below a certain value in one fourth further starting mode, the second gear and the reverse gear are inserted so that a continuous switching between them is possible. 33. The method in particular according to one or more of claims 30-32, characterized in that the third further starting mode from the second another start mode or the fourth further start mode from the third further start-up mode can be selected automatically if in second or in the third further start-up mode, several short ones  successive change of direction and / or a winter mode and / or a spinning of the driven wheels can be detected. 34. The method in particular according to one or more of claims 30-33, characterized in that the reverse gear can be disengaged, if a certain distance has been covered while driving forward and / or a certain speed is exceeded. 35. The method in particular according to one or more of claims 28 and / or 30, characterized in that the additional Gear ratio is used if an increased drive torque is required and / or a, in particular thermal, relief of the input side Coupling unit is necessary and / or a crawl operation is desired. 36. Method in particular according to one or more of claims 29 and / or 32, characterized in that the Translation level with the second highest translation is used if a reduced drive torque is desired and / or a larger one, in particular thermal, load on the input side Coupling unit can be approved.   37. Method in particular according to one or more of claims 28-32, characterized in that, if necessary, a downshift to additional translation stage is carried out.