DE10063847A1 - Discrete gearbox for motor vehicle has at least one switchable coupling that transfers torque from gear wheel to another gear wheel of different set of gear wheels - Google Patents

Abstract

The device has at least two gear shafts, an input shaft (24) and an output shaft (22) and several sets of gear wheels (1-10) with different reductions whose gear wheels are mounted on the gear shafts for coupling into the force transfer path between the input and output shafts. At least one switchable coupling (11-18) is provided that transfers the torque from a gear wheel to another gear wheel of a different set of gear wheels.

Description

The invention relates to a multi-step transmission for a motor vehicle according to the Preamble of the main claim.

It is already known that multi-step transmissions according to the prior art, which do not use planetary gear sets, the different gear ratio represent tongues by pairing non-coaxially mounted gears.

A gear pair or several series pairings from with gears in mesh with one another determine the overall transmission ratio of the gear engaged.

At least one gear of the entire torque flow is not shaped per gear conclusively connected to the associated gear shaft when the gear is not one is laid. If this gear is to be switched, a suitable el connection between gear and shaft and the moment flow.

One possibility is the so-called direct gear in multi-step transmissions with coaxial drive and output shaft. The direct aisle is under Um all gear pairs through direct connection of the drive and Ab shown drive shaft.  

Another option is reverse gear. In the backward momentum flow ganges is a gear pair with an odd number of teeth wheels to realize the speed reversal.

The disadvantage of conventional multi-step transmissions without planetary gear sets is that that each gear pairing is usually only used in one gear step det.

An exception is the so-called constant toothing in multi-step transmissions with coaxial input and output shaft, which in the torque flow of everyone Ganges other than the direct one.

Inline gearboxes of the type described therefore require a number of n Forward gears and a reverse gear an equally large number n of teeth gear pairs. The ratio of gears / number of gear pairs is 1.

EP 984 202 A1 describes a change gear according to the prior art, with sixteen forward gears in all possible switching states.

Here the torque is either from a gear to a shaft or vice versa or from one wave to another wave. This is achieved through the optional separation or connection via form or Frictional connection of a shaft with a gearwheel mounted on this shaft or two coaxially lying periods.

With this design, the ratio of gears / number of gear pairs is larger as 1. However, not all possibilities have been exploited, this ratio to enlarge further.

It is therefore an object of the invention to design a multi-step transmission that its gears and shafts can be interconnected in a very flexible sequence  are, so that with a number of n gear pairs, a number of gears fen is much larger than n.

The object is achieved with the features of claim 1. Further design the invention results from the subclaims.

According to the invention is a multi-step transmission, for torque or speed adaptation between a drive motor and an axle drive of a force vehicle, with at least two transmission shafts, an input shaft and one Output shaft and with several gear sets with different gear ratios, whose gears are held on the gear shafts and for torque transmission via switchable couplings in the power flow between the input shaft and Output shaft can be coupled, characterized in that at least one switchable clutch is provided, the torque of one Transmits gear to another gear of another gear set.

This has the advantage that the forwarding of a rotary movement from a first one Gear on a second, which is mounted on the same shaft or axis becomes light without this shaft or axis due to the transmitted torque strain. Both gears form a hollow shaft.

The shaft or axis serving as a bearing for both gears can move of the total torque flow within the gearbox for the transmission of Serve torque. Also for the storage of other gear components.

By connecting toothed gears mounted on the same shaft it is possible to use the hollow shafts formed and to support this tooth wheel serving shaft for the transmission of mutually independent torque elements and / or speeds to use.

This advantageously also enables a more compact construction of gears, which then take up less installation space.  

In an advantageous embodiment of the invention, at least one switchable Coupling provided the torque from one gear to a second shaft transmits, which is coaxial to a first shaft on which the gear is det.

This has the advantage that gears and shafts in an even more flexible order are collectively switchable, so that with the number of gear pairings one more larger number of gear steps is to be displayed.

In a preferred embodiment of the invention there is at least one gear Pairing of a gear set made exclusively from idler gears. This he enables an even more compact construction of gearboxes, which is even less Take up installation space.

Another advantageous embodiment of the invention provides that at least one such a switchable clutch, the torque from one gear to another Gear of another gear set or transmits to a shaft, a switchable rer freewheel is.

Such an arrangement with switchable freewheels is advantageously simple build up and operate reliably.

Preferred embodiments of the invention are described in the following spelling with the accompanying drawing. Show it:

Fig. 1 shows a schematic representation of a possible transmission according to the invention,

Fig. 2 sixteen schematic representations of the switching positions of the Ge drive according to Fig. 1,

Fig. 3 shows a further embodiment of a possible transmission according to the invention in a schematic representation;

Fig. 4 is a schematic representation of a shift position of the transmission according to Fig. 3,

Fig. 5 shows two schematic representations of switching positions of the Getrie bes corresponding to FIG. 3, with additional power take-off,

Fig. 6 shows a further embodiment of a possible transmission according to the invention in a schematic representation;

Fig. 7 is a schematic representation of a shift position of the transmission according to Fig. 6,

Fig. 8 shows four schematic representations of shift positions of the transmission according to Fig. 6, with an additional power take-off,

Fig. 9 is a simplified embodiment of a transmission according to Fig. 6 in a schematic representation;

Fig. 10 are schematic representations of eight switching positions of the Getrie bes corresponding to FIG. 9,

Fig. 11 shows a simplified embodiment of a transmission according to Fig. 3 in a schematic representation

Fig. 12 twelve schematic representations of switching positions of the Getrie bes according to Fig. 11.

Fig. 1 shows a schematic representation of a possible transmission according to the invention, with five gear pairs. Switching stages for eight forward gears and eight reverse gears are thus achieved. The ratio of gears / number of gear pairs is 3.2. Taking into account only one reverse gear required in practice, the ratio is 1.8.

Five gearwheels 1 , 2 , 3 , 4 , 5 are held as idler gears on an output shaft 22 of a multi-step transmission. Each of these idler gears meshes, for torque or speed adjustment between a drive motor, not shown, and an axle drive, not shown, of a motor vehicle, each with one of five further gears 6 , 7 , 8 , 9 , 10 , also held as idler gears on a countershaft 23 . The gears 1 , 2 , 3 , 4 , 5 form with the other gears 6 , 7 , 8 , 9 , 10 five gear sets of different gear ratios, elements for the manufacture and for releasing force, form, or friction in the stepped gearbox built-in are. Switchable clutches 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , which can be coupled into the power flow between input shaft 24 and output shaft 22 , then transmit torque from one idler gear to another idler gear of another gear set by , Form, or frictional connection between two gears 1 , 2 , 3 , 4 , 5 or 6 , 7 , 8 , 9 , 10 mounted on a common shaft.

Another switchable clutch 19 is provided between the output shaft 22 and the gear 5 . This produces force, form, or frictional connection between a shaft and an idler gear mounted on this shaft.

A torque can be applied to the input shaft 24 of the multi-step transmission via an engine crankshaft (not shown).

This torque can either be applied from the input shaft 24 directly to the output shaft 22 via a further switchable clutch 20 , which produces a force, form, or frictional connection between two coaxial shafts, or this torque can be applied via an additional switchable clutch 21 , are brought up from the input shaft 24 to the gear 1 of the multi-step transmission. In this case, the torque is transmitted by force, form, or friction from a shaft to a gear 1 , which is mounted on another, coaxial to the aforementioned shaft.

As a supplement, it should also be mentioned that a gear wheel 60 for speed reversal is interposed between the gear wheel 5 and the gear wheel 10 .

Fig. 2 shows with sixteen schematic representations all the possibilities of the torque flow, as well as the switching positions of the ele ments required for the production of force, form or friction. The reference numerals are not inserted, they correspond to those of Fig. 1. Furthermore, closed couplings are highlighted in black, open couplings corresponding to those shown in Fig. 1.

In shift position 1 , the direct gear is engaged by only clutch 20 being closed. Direct gear has advantages over the prior art in that transmission efficiency is better. With direct gear engaged, all components not involved in torque transmission stand still, whereas in the case of gearboxes according to the prior art, all gearwheels are towed without load.

In shift position 2 , the clutch 21 , the clutches 12 , 13 , 14 , 15 and the clutch 19 are closed. The torque is thereby, as shown by the arrow, on the gears 1 , 6 and 7 on the countershaft 23 and further via a through the coupled gears 2 , 3 , 4 and 5 hollow shaft and via the clutch 19 to the output shaft 22 .

The other switch positions shown are to be interpreted accordingly, whereby the dark-colored coupling symbols mean that force, shape or Friction is maintained by this clutch while not underlaid Coupling symbols mean that the respective couplings are not activated. The arrow drawn in gray indicates the torque flow through the Ge drives and the components loaded with them. This applies to all figures, as far as sol che symbols are drawn.

The number of gear stages that can be displayed increases very rapidly with the number of gear pairs. In the case of an inline transmission corresponding to the type shown in FIGS. 1 and 2, the number of gear stages that can be represented per further gear unit increases twice. For such a transmission with six gear pairs, 16 forward gears and 16 reverse gears can already be realized.

The high number of gear stages allows an internal combustion engine to be operated always close to the operating point z. B. maximum performance or minimum consumption and is thus for z. B. racing or use in commercial vehicles significant.

Such a gear construction also allows the representation of very high Ge drive spreads, which the use of a switchable transfer case for all could make wheel-driven vehicles unnecessary. This would also have ent speaking interpretation of the overall translation advantages when loading the An Driving clutch of the vehicle: B. on the mountain, with a trailer or in Off-road, the clutch load can be changed by shifting the lowest gear be significantly reduced.

The type of representation of a very highly translated smallest gear has also Component strength advantages. The large gear ratio can be Increments can be realized. This allows more even teeth Pairings are used as is the case with prior art gearboxes is possible. Critical gears with very small numbers of teeth are not necessary.

Figure 3 shows. Based on FIGS. 1 and 2, such a transmission scheme may be stopped by de-coupling in the transmission components as an example.

In addition to the five gears 1 , 2 , 3 , 4 , 5 on the output shaft 22 of the gearbox and the five further gears 6 , 7 , 8 , 9 , 10 on the countershaft 23 , each by the switchable clutches 11 , 12th , 13 , 14 or 15 , 16 , 17 , 18 , can be connected to hollow shafts which are concentric with the output shaft 22 or countershaft 23 , it is possible to use additional elements for producing and releasing force gears 2 , 3 and 4. , Form, or friction to connect independently of the output shaft 22 . Likewise, the gears 7 , 8 , 9 and 10 can be connected to the countershaft 23 . These further additional switchable clutches 30 , 31 and 32 on the output shaft 22 or 33 , 34 , 35 and 36 on the countershaft 23 , like the further switchable clutch 19 , have a force, form or frictional connection between a shaft and one this shaft mounted gear.

In addition, the further switchable clutch 20 and the additional switchable clutch 21 according to FIG. 1 are installed in the multi-step transmission.

For this purpose, Fig. 4 is a shift position of the transmission according to Fig. 3, which corresponds to the switch position 2 of Fig. 2 from the loaded reduction forth. The non-registered reference numerals also correspond to those of FIG. 3. In FIG. 2, shift position 2 , transmission components which do not transmit any torque also take part in the movement of the torque-transmitting wheel sets. In contrast, in the example of FIG. 4, the non-torque-transmitting wheel sets do not participate in the movement of the torque-transmitting wheel sets.

This shows that by placing additional elements to make power, Form or frictional engagement is possible that not only in direct gear part of the Gear components is stopped, namely those that are not used to transmit rotation moment in the respective switch position. This results in Efficiency advantages due to reduced splashing losses.

Fig. 5 shows two schematic representations of the shift positions of the transmission corresponding to Fig. 3 with additional power take-off. The main torque flow through the transmission and its branching to other units are shown. An arrow drawn in gray indicates the torque flow of the power take-off through the transmission and the components that act on it.

It is in fact possible to place elements accordingly Position of force, form or friction, the moment flow within the Ge drive into a power take-off in such a way that others not shown Aggregates such as B. electric motors for short-term performance improvement, Generators for braking energy recovery or drive train elements for All-wheel operation can be switched on. With this torque overlay The main moment drawn with a solid gray arrow remains The flow of flow through the transmission is undisturbed.

This can be done in such a way that the power take-off runs at a speed that is either proportional to the engine speed, as shown in FIG. 5a, or that is proportional to the vehicle speed, as in FIG. 5b.

, The switchable coupling 33 has been the implementation of the power take-off according to FIG. 5a, starting from the shift position corresponding to Fig. 4 additionally acti fourth while correspondingly for the auxiliary drive of Fig. 5b, the two clutches 31 and 34 were closed. The reference numerals correspond to those in FIG. 3.

Fig. 6 shows a further embodiment of a possible transmission according to the invention, in a schematic representation. With 9 gears and an additional gear for speed reversal in the reverse gears, this design allows a total of 9 forward and 8 reverse gears. The small construction width of the multi-step transmission is an advantage.

Three gear wheels 41 , 42 , 43 are held as idler wheels on the input shaft 24 of this multi-step transmission. Each of these gears 41 , 42 , 43 meshes, for torque or speed adjustment between a drive motor, not shown, and an axle drive, not shown, of a motor vehicle, each with one of three further gear wheels 44 , 45 , 46 on an intermediate shaft 40 . These further gears 44 , 45 , 46 in turn mesh with three additional gears 47 , 48 , 49 on the output shaft 22 . With these three gear sets, due to the elements built into the multi-step transmission for producing and releasing force, form, or friction, different torque flows with different ratios are possible. The switchable clutches 11 , 12 , 13 , 14 , 15 , 16 , which can be coupled into the power flow between the input shaft 24 and the output shaft 22 , transmit torque from one gearwheel to another gearwheel of another gearwheel set by using force, form, or produce a frictional connection between two gear wheels 41 , 42 , 43 or 44 , 45 , 46 or 47 , 48 , 49 mounted on a common shaft.

Additional switchable clutches 51 , 52 or 53 , 54 or 55 , 56 , 57 are provided between the shafts 24 or 40 or 22 and the gears 42 , 43 or 44 , 46 or 47 , 48 , 49 . These produce force, form, or frictional connection between a shaft and a gearwheel mounted on this shaft.

A torque can be applied to the input shaft 24 of the multi-step transmission via a drive shaft 50 .

This torque can either be applied from the drive shaft 50 directly to the input shaft 24 via an additional switchable clutch 20 , which establishes a force, form, or frictional connection between two coaxial shafts, or this torque can be applied via an additional switchable clutch 21 , the force, form, or frictional connection between a shaft and a gear can be applied from the drive shaft 50 to the gear 41 of the gear selector gear. In this case, the torque is transmitted from a shaft to a gearwheel which is mounted on another shaft lying coaxially to the aforementioned shaft.

Fig. 7 shows a schematic representation of a shift position of the transmission accordingly Fig. 6, wherein the torque flow and the switching state of the hitch be elements, as explained for the previous figures, is shown. There is even a crossover of the moment flow here. This additional possibility of displaying an overall gear ratio has advantages, particularly in front-transverse applications, due to a very short gearbox with many gear stages. Of great advantage is the optional separation or connection of gear components as suggested, especially in gear pairs with gear pairs of more than two meshing gears.

The non-inserted reference numerals correspond to those of Fig. 6. In this switching position, the further clutch 20 , the further additional hitch beings 51 , 53 , 54 , 55 and the clutch 16 is closed. The torque is transmitted through, as shown, from the input shaft 24 via the gears 42 , 45 , 46 , 48 and 49 to the meantime 40 and from there via the gears 44 and 47 to the output shaft 22 .

Fig. 8 shows four schematic representations a, b, c, d of the switching positions of the gearbox according to FIG. 6 with additional power take-off. This switchable power take-off can run by activating various elements for the manufacture of force, form or frictional engagement with a large number of ratios.

The non-inserted reference numerals correspond to those of Fig. 6. In all four switching positions, the main torque flow of the torque from the drive shaft 50 to the activated after further clutch 20 to the input shaft 24 , then through the activated additional clutch 51 from the gear 42 on the gear 45 . By additionally activating clutches, a second torque flow (shown in dashed lines) is generated in the transmission. The main torque flow (solid gray arrow) is passed through the two closed clutches 13 and 55 via the gears 44 and 47 to the drive shaft 22 . Through additional activation of clutch 57 ( FIG. 8a), clutch 16 ( FIG. 8b), clutch 14 ( FIG. 8c) or clutch 52 ( FIG. 8d), the torque flow of the power take-off is generated in the transmission, which at the end of the gear 49 is delivered. To add, it should also be mentioned that between the gear 44 and the gear 47, a gear 60 for speed reversal is interposed.

Furthermore, it is also conceivable, by a switchable power take-off from outside Components lying half of the main torque flow more than a translation stage for ancillary units.

Fig. 9 shows a simplified embodiment of the transmission according to Fig. 6, in a schematic representation. With 9 gears and an additional gear for speed reversal in the reverse gears, this construction allows a total of 6 forward and 2 reverse gears. The small overall width of the multi-speed transmission, only three gear widths, is an advantage.

The wheelset of this front-transverse transmission is mounted on two axes 24 , 40 , an axis, not shown, for mounting the gear 60 for reverse gear speed reversal and a shaft 22 . The gear 60 for reverse gear speed reversal is in a gear pair A, consisting of four meshing gears 41 , 44 , 47 , 60 , each of which is freely rotatable on the associated shaft or axis 22 , 24 , 40 . The gears 42 , 45 , 48 and 43 , 46 , 49 of two further gear pairs B and C, each with three meshing gears 42 , 45 , 48 and 43 , are mounted on the associated shaft or axis 22 , 24 , 40 in the same way , 46 , 49 .

Three gears 41 , 42 , 43 are held as idler gears on the axis 24 of this stepped transmission. Each of these gear wheels 41 , 42 , 43 meshes, for torque or speed adjustment between a drive motor, not shown, and an axle drive, not shown, of a motor vehicle, each with one of three further gear wheels 44 , 45 , 46 on the further axis 40 . These idler gears, in turn, drive three additional gears 47 , 48 , 49 on the output shaft 22 , although the gear 60 for reverse gear speed reversal is connected between the further gear 44 and the additional gear 47 . With these three gear sets A, B, C ver due to the built-in elements in the gearbox for the manufacture and release of force, form, or friction different torque flows of different gear ratios possible. The switchable couplings 11 , 12 , 13 , 14 , 15 , 16 , which can be coupled into the power flow between drive shaft 50 and output shaft 22 , transmit torque from one idler gear to another idler gear of another gear set A or B or C, by force, form, or frictional engagement between two gear wheels 41 , 42 , 43 and 44 , 45 , 46 and 47 , 48 , 49 mounted on a common shaft.

Further additional switchable couplings, as shown in Fig. 6, are not seen before.

Via the drive shaft 50 , a torque can be applied to the gearwheel 41 of the stepped transmission, which is forwarded according to the eight shift positions a, b, c, d, e, f, g, h shown schematically in FIG. 10. The torque flow and the switching state of the clutch elements are shown as already explained.

The non-registered reference numerals correspond to those of Fig. 9. In all eight switch positions, the axes 24 and 40 are not loaded by the torque transmission. The main torque flow is guided by the drive shaft 50 , depending on the switching position, directly over the idler gears or over their hubs coupled together to the output shaft 22 . In the switching positions a and h each a reverse gear is switched because the gear 60 is interposed between the gear 44 and the gear 47 for speed reversal and the torque flow is guided via this gear 60 .

Fig. 11 shows a simplified embodiment of the transmission according to Fig. 3, in a schematic representation. This construction allows a total of 8 forward and 4 reverse gears. The small overall width of the multi-step transmission, of just five tooth widths, is an advantage.

The wheel set of this inline transmission consists of three shafts 22 , 23 , 24 , an axle (not shown) for mounting the gear 60 for reverse speed reversal, four gear pairs A, B, C, D, each with two meshing gears, of which Except for the gear wheel which is fixedly connected to the shaft 24 , each is rotatably mounted as an idler gear on the associated shaft 22 , 23 . In addition, from a gear pair E with three mesh with each other, the gears connected to the associated shaft 22 , 23 .

Fig. 12 shows twelve schematic representations a, b, c, d, e, f, g, h, i, k, l, m of the shift positions of the inline transmission according to Fig. 11, the torque flow and the switching state of the clutch elements is shown.

Claims (4)

1. multi-speed transmission, for torque or speed adjustment between a drive motor and an axle gear of a motor vehicle, with at least two gear shafts, an input shaft ( 24 ) and an output shaft ( 22 ), and with several gear sets with different gear ratios, the gears ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ) are held on the gear shafts and for torque transmission via switchable clutches ( 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 21 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 51 , 52 , 53 , 54 , 55 , 56 , 57 ) in the power flow between Input shaft ( 24 ) and output shaft ( 22 ) can be engaged, characterized in that at least one switchable clutch ( 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ) is provided, the torque of a gear ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ) to another gear ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ) transmits another gear set. 2. multi-step transmission according to claim 1, characterized in that at least one switchable clutch ( 21 ) is provided, which transmits torque from a gear ( 1 ) to a second shaft which is coaxial with a first shaft on which the gear ( 1 ) is located. 3. multi-step transmission according to claim 1 or 2, characterized in that at least one gear pair of a gear set exclusively consists of idler gears.   4. multi-step transmission according to one of claims 1 to 3, characterized in that at least one such switchable clutch ( 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 21 ), the torque of a gear ( 1 , 2nd , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ) to another gear ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ) of another gear set or transmits to a shaft, is a switchable freewheel.