DE102020201411A1 - Switchable transmission as well as trailer axle and vehicle trailer with such a transmission - Google Patents

Abstract

The present invention relates to a switchable transmission, comprising: a housing (1), a first planetary gear (11) with a sun gear (7), a first ring gear (3) and at least one first planetary gear (4), the gear (1) as well having a second planetary gear (12) with a second ring gear (13) and at least one second planet gear (5), the second planetary gear (12) in particular not having a sun gear, the first ring gear (3) and the second ring gear (13) being free are rotatably arranged in the housing (1), the sun gear (7) being connected to an input shaft. The transmission (1) also has a planet carrier (6), the first planet gear (4) and the second planet gear (5) being connected to one another in a rotationally fixed manner and being rotatably mounted on or in the planet carrier (6). The transmission (1) also has a first clutch (K1) which is provided between the first ring gear (3) and the housing (1) and is designed to couple the first ring gear (3) to the housing (1) in a rotationally fixed manner or to release, as well as a second clutch (K2) which is provided between the planet carrier (6) and the housing (1) and is set up to couple or release the planet carrier (6) with the housing (1) in a rotationally fixed manner. The transmission (1) also has an output shaft (15) which is connected to the second ring gear (13), and in particular a control unit (16) which is set up to include the first clutch (K1) and the second clutch (K2) to control.

Description

State of the art

The present invention relates to a switchable transmission, a trailer axle with such a switchable transmission and a vehicle trailer, in particular a caravan trailer or a truck trailer or a car trailer or the like. With such a vehicle axle.

Vehicle trailers, e.g. caravans or truck trailers or the like, are moved by means of tractors. After arriving at a destination, it is often necessary to maneuver to the final destination (e.g. a loading ramp or a parking space for a caravan trailer). Maneuvering with the tractor is difficult, especially when reversing, and partly not possible due to a lack of space. Then such trailers are often uncoupled from the tractor for maneuvering and moved by hand, which is very forceful. Or they are moved by means of a maneuvering drive, which drives the trailer's wheels directly via a movable drive roller on the trailer's tires. Such a maneuvering drive is usually provided on each tire of the trailer. In the case of caravans, drive energy from such a maneuvering drive is taken from a 12V on-board battery in the caravan, for example.

For example, the EP 1 225 090 A2 such a maneuvering drive.

Disclosure of the invention

The switchable transmission according to the invention with the features of claim 1 has the advantage that the switchable transmission is not only designed for electrical maneuvering, but also offers operation of an electrical machine as a generator, e.g. as a charging option for an energy store and / or as a thrust support or a reduction in the trailer mass to be pulled for the towing vehicle. The switchable transmission of the invention has a simple and robust structure and requires only a minimal amount of installation space. It can easily be arranged on or in a trailer axle, e.g. in the immediate vicinity of a wheel connected to the trailer axle. Furthermore, by means of the switchable gear, a very high spread can be provided for the gear ratios of the individual gears, for example a first gear ratio (a first gear stage) can be in a range from 1: 1 to 14: 1 (only the second planetary gear is active) and / or a second gear ratio (a second gear stage) can have a second gear ratio in a range from 30: 1 to 450: 1, preferably for example 50: 1 to 350: 1 (both planetary gears are active). When used on a vehicle axle, the shiftable transmission also enables a reduction in wear on the wheels on the vehicle axle, since the prior art drive rollers rolling on the wheels can be dispensed with. In particular, the switchable transmission enables recuperation operation in addition to maneuvering. It can charge an energy storage device or supply electrical consumers in the trailer directly with electrical energy during a journey, if the switchable transmission is arranged on or in a trailer axle, for example. The on-board network of the towing vehicle is advantageously relieved or no longer required at all for supplying this consumer.

This is achieved according to the invention in that the switchable transmission has a housing as well as a first planetary gear and a second planetary gear. The first planetary gear comprises a (first) sun gear, a first ring gear and at least one first planet gear. The second planetary gear includes a second ring gear and at least one second planet gear. The first ring gear and the second ring gear are freely rotatable in the housing of the switchable transmission. The (first) sun gear of the first planetary gear is connected to an input shaft (first shaft). The transmission also has a planet carrier. The first planet gear and the second planet gear are non-rotatably connected to one another and rotatably mounted on or in the planet carrier.

Furthermore, a first clutch is provided, which is arranged between the first ring gear and the housing. The first clutch is set up to couple or release the first ring gear to the housing in a rotationally fixed manner. The first clutch thus enables the first ring gear to either rotate relative to the housing or for the first ring gear to be retained relative to the housing. If the first ring gear can rotate, it rotates counter to the direction of rotation of the (first) sun gear and the first planet gear also rotates counter to the direction of rotation of the (first) sun gear.

Furthermore, a second clutch is provided, which is arranged between the planet carrier and the housing. The second clutch is designed to couple or release the planet carrier with the housing in a rotationally fixed manner. Thus, the second clutch enables the planet carrier to either rotate relative to the housing or the planet carrier to be retained relative to the housing. If the planet carrier can rotate, it rotates in the same direction of rotation as the (first) sun gear and the first planet gear rotates in the opposite direction to the direction of rotation of the (first) sun gear.

An output shaft (second shaft) is connected to the second ring gear.

It can be provided, for example, that the second planetary gear does not have a sun gear. In other words: it then only consists of the at least one second planetary gear and the second ring gear. Should a second sun gear be provided in the second planetary gear, this would be coupled exclusively to the at least one second planet gear. In the following text, when the term “sun gear” is used, the (first) sun gear of the first planet gear is always to be understood, unless something else is expressly described.

Furthermore, for example, the transmission can have a control unit which is set up to control the first and second clutches. However, this control unit can also be present separately. For example, it can be provided in an external control unit, e.g. a Vehicle Control Unit (VCU). It can then be connected to the gearbox via signal lines and control lines for the clutches, for example.

In the context of this application, the term “clutch” (first clutch, second clutch) is initially to be understood functionally. This means: the coupling can connect or release one element to another element. Thus, the first and second clutch can be implemented, for example, by a (single mechanical) part, as long as it can produce the different switching states. However, it can also be provided, for example, that the first clutch and the second clutch are implemented by two mutually separate, independent components.

It goes without saying that the transmission can have precisely one first planetary gear. However, it is also possible that several first planet gears are provided, e.g. two, three, four, five or even more first planet gears.

It is also understood that the transmission can have exactly one second planetary gear. However, it is also possible that several second planet gears are provided, e.g. two, three, four, five or even more second planet gears. The number of second planet gears can preferably be equal to the number of first planet gears.

More preferably, the switchable transmission is set up to be axially connected to a shaft of a wheel. This can e.g. be arranged on a trailer axle.

Preferably, the number of teeth of the first ring gear and the second ring gear are different, they therefore differ by at least one tooth. The following applies: the smaller the difference in the number of teeth, the higher the gear ratio can be (depending on the switching status of the first and / or second clutch).

For example, a number of teeth of the first planetary gear and the second planetary gear are the same. If the number of teeth of the first ring gear and the second ring gear are different in this case, a profile shift on the first ring gear, on the second ring gear or on both ring gears may be necessary due to a difference in center distance.

For example, a number of teeth of the first planetary gear and the second planetary gear are different.

If a number of teeth of the first ring gear and a number of teeth of the second ring gear differ, a reversal of the direction of rotation (input shaft to output shaft) can be effected depending on which of the two ring gears has more teeth.

The ratio of the number of teeth of the first ring gear ( Z3 ) to the number of teeth of the second ring gear ( Z5 ) for example in the range from 1: 1.01 to 1: 1.5, preferably in the range at least 1: 1.012 to 1: 1.08. For example, the number of teeth of the first ring gear 60 and that of the second ring gear 57 or the number of teeth of the first ring gear can be 74 and that of the second Ring gear 72 . It goes without saying that the number of teeth can also be exactly the other way round (eg Z3 = 57 and Z5 = 60) if the direction of rotation of the output shaft is to be reversed compared to the first example. Thus the ratio always refers to the ratio of the larger number of teeth to the smaller number of teeth of the two ring gears.

This gear topology makes it possible, for example, for a trailer axle to be operated in a maneuvering mode on the one hand and on the other hand this gear topology enables an electric motor drive mode and / or a generator mode if an electric machine is arranged on the input shaft. For example, during a normal train ride of the trailer in a hitched-up state on a tractor, an electrical machine which is arranged on the input shaft (first shaft) can be operated as an electric motor and provide additional support for the tractor. In generator mode, the electrical machine can then, for example, charge an energy storage device installed on the vehicle trailer or directly supply electrical consumers located in the vehicle trailer, for example a refrigerator or a cooling unit or the like, with electrical energy.

Since the shiftable transmission has two planetary gears arranged (directly) one behind the other, a small installation space can be realized for the shiftable transmission. The transmission designed in this way is advantageously protected in a particularly simple manner against the ingress of dirt or impurities. Furthermore, the manufacturing costs for the switchable transmission, particularly when installed in or on a trailer axle, can also be very low. Depending on a desired operation of an electrical machine connected to the shiftable transmission, a drive mode can be implemented in which the electrical machine is operated as an electric motor (drive motor) or a recuperation mode can be implemented in which the electrical machine is operated as a generator. In drive mode, i.e. when the electric machine is operated as an electric motor (drive motor), a shunting gear and also a drive gear, in which the electric machine supports a tractor, can be set by means of the switchable gear.

In a first gear stage in maneuvering mode, relatively short distances are usually covered, for example a few meters, for example less than 500 m or less than 100 m or even only less than 20 m. The speed in maneuvering mode is preferably low, for example less than 10 km / h , preferably less than 6 km / h, particularly preferably less than 3 km / h, more preferably less than 1 km / h. When maneuvering, a relatively high torque can be requested from a wheel driven by a trailer axle.

A second gear stage can be used, for example, when driving, e.g. in a train operation, in which longer distances, e.g. more than 10 km or more than 100 km or more than 500 km, are covered. In train operation, higher speeds are often reached, e.g. more than 70 km / h, which means that the wheel of a trailer axle rotates correspondingly quickly and this speed has to be recorded in the switchable transmission.

It should be noted that for the description of the invention, the input shaft (first shaft) of the switchable transmission is always the shaft that is connected to the electrical machine and the output shaft (second shaft) of the switchable transmission is always the shaft that is connected to it a wheel of a trailer or the like. In connection. For a person skilled in the art, it goes without saying that when the electrical machine is switched from use in generator mode to motor mode (electric motor), the power flow in the system is reversed. This basically turns the previous output shaft of the transmission into the input shaft and vice versa. Nevertheless, to avoid ambiguity in the description, the terms "input shaft" and "output shaft" are retained regardless of the operating mode of the electrical machine (i.e., reference is always made to a power flow in motor operation - in generator operation, the names must therefore be swapped) .

In the context of this application, the terms “comprising”, “comprising” are used synonymously with the terms “having”, “having”, unless otherwise described.

An axial direction extends along an axis, for example an axis XX (see 1 ). A radial direction extends perpendicular to the axial direction and a revolving direction denotes the direction revolving around the axial direction.

In motor operation, the input shaft could also be referred to as the drive shaft and the output shaft as the output shaft.

The subclaims show preferred developments of the invention.

In a further development it is provided that the first planetary gear and the second planetary gear have a common planetary gear axle, the first planetary gear and the second planetary gear being non-rotatably connected to the planetary gear axle, the planetary gear axle being rotatably mounted in the planetary gear carrier.

This advantageously makes it possible to implement a particularly simple structure, in particular if the first planetary gear and the second planetary gear have different numbers of teeth. Then, for example, the first planetary gear and the second planetary gear can advantageously be manufactured separately from one another and finally connected to the planetary gear axle. This also makes it easy to exchange one of the planetary gears if, for example, a different gear ratio is to be produced. In this context, the planetary gear axle is not only to be understood as a virtual axis, but also as a (planetary gear) shaft.

Alternatively or additionally, it can be provided, for example, that the first planetary gear and the second planetary gear are not connected to one another via an axle, but rather are directly coupled to one another. In this case, for example, they can each have a coupling element on their axially outwardly facing end face, with which they are mounted on or in the planet carrier. The coupling element can, for example, be a pin. Alternatively, it can also be provided, for example, that the two planet gears are made from one piece and have a bore or the like in their center. An axle, for example, can then be guided through this hole. This axis can, for example, be non-rotatably connected to the planet carrier and belong to it. The two planet gears thus rotate around the axis belonging to the planet carrier.

It is preferably provided that the output shaft is mounted in the housing.

For this purpose, the output shaft can be mounted in a cover or a base of the housing, for example. For example, the housing can be designed with a first bearing and / or with a second bearing for this purpose. The first and / or second bearing can be provided, for example, in the base and / or in the cover of the housing. The cover and / or the base can, for example, have a cylindrical bearing area in which one or more bearings for the output shaft are arranged.

This advantageously brings about a radial stabilization of the output shaft and a reduction in friction, thus improving the efficiency of the transmission.

A particularly simple and secure sealing of the interior of the housing of the transmission against fluid media, dirt and impurities can thereby also advantageously be effected, as a result of which the service life of the transmission can be increased.

A particularly compact structure with a low weight can also advantageously be achieved in this way.

It can furthermore be provided that the input shaft is passed through the base (or the cover) of the housing (if the output shaft is passed through the cover (or the base)). In this case, the input shaft can preferably also be mounted on the housing base. This, too, is used for smooth running, radial stabilization of the input shaft and sealing of the interior of the housing.

The input shaft and the output shaft of the switchable transmission are preferably arranged on a common axis. This axis is initially to be understood as a virtual axis. For example, it can be an axis of symmetry of the gearbox or its housing.

This advantageously results in a particularly compact design. Furthermore, the risk of an imbalance is advantageously reduced and the housing is loaded with fewer forces, especially in the radial direction. This in turn enables, for example, a lower wall thickness of the housing and thus material and cost savings.

More preferably, the output shaft (second shaft) is formed in one piece with the second ring gear. This enables a particularly simple and cost-effective structure.

It is advantageously provided that the first clutch is a friction clutch and / or that the second clutch is a friction clutch.

Alternatively or additionally, it can advantageously be provided that the first coupling is a claw coupling and / or that the second coupling is a claw coupling.

• ■ die erste Kupplung ist eine Reibkupplung. Die zweite Kupplung ist eine Reibkupplung oder eine Klauenkupplung oder eine andere Kupplungsart.
• ■ Die erste Kupplung ist eine Klauenkupplung. Die zweite Kupplung ist eine Reibkupplung oder eine Klauenkupplung oder eine andere Kupplungsart.
• ■ die zweite Kupplung ist eine Reibkupplung. Die erste Kupplung ist eine Reibkupplung oder eine Klauenkupplung oder eine andere Kupplungsart.
• ■ Die zweite Kupplung ist eine Klauenkupplung. Die erste Kupplung ist eine Reibkupplung oder eine Klauenkupplung oder eine andere Kupplungsart.

The following combinations are possible:

• ■ the first clutch is a friction clutch. The second clutch is a friction clutch or a dog clutch or another type of clutch.
• ■ The first coupling is a claw coupling. The second clutch is a friction clutch or a dog clutch or another type of clutch.
• ■ the second clutch is a friction clutch. The first clutch is a friction clutch or a dog clutch or another type of clutch.
• ■ The second coupling is a claw coupling. The first clutch is a friction clutch or a dog clutch or another type of clutch.

Other types of coupling for the first coupling and the second coupling are also conceivable.

The advantage of using a claw coupling is that the torque that can be transmitted is increased due to the form-fitting connection - this prevents the coupling from slipping. This makes shunting operations easier, in particular.

The advantage of using a friction clutch is the possibility of the clutch slipping if the torque is too high. In this way, damage to the transmission or the gears arranged therein can be prevented.

It is possible to design the first clutch and the second clutch differently or to design them as the same type of clutch.

In a further development it is provided that a shift sleeve is provided that is non-rotatably mounted in the housing and axially displaceable with respect to the housing, the first clutch and / or the second clutch being shiftable by means of the shift sleeve. The shift sleeve can, for example, have internal teeth, the internal teeth then being positively connected, for example, to external teeth on the first ring gear and / or to external teeth on the planet carrier, depending on the switching position.

This advantageously creates a particularly robust and compact transmission which enables a high torque transfer for the elements that can be coupled by the shift sleeve. A type of brake or parking brake can also be implemented with the shift sleeve. The shift sleeve acts as a kind of dog clutch.

For example, the shift sleeve can be coupled to the first ring gear in a first position and thus connect it to the housing in a rotationally fixed manner and release the planet carrier. In a second position, it can be coupled to the planet carrier, for example, and thus connect it to the housing in a rotationally fixed manner and release the first ring gear. In a third position, the shift sleeve can release both the planet carrier and the first ring gear (idling). In a fourth position (blocking position or parking position) it can be coupled both to the first ring gear and to the planet carrier and connect both elements to the housing in a rotationally fixed manner. Then the transmission is blocked and the shift sleeve acts like a parking brake. This can, for example, increase the theft security for a vehicle connected to the transmission. It goes without saying that not all four of the four positions have to be implemented in the transmission. The shift sleeve can, for example, be set up in such a way that it can only implement the first position or only the second position. Or just the first and second positions, etc.

The four positions can also correspond to four switching states or four modes.

With the shift sleeve, a single mechanical element can thus effect one of the two clutches or even realize both clutches. As a result, the transmission can be manufactured and operated in a particularly inexpensive and simple manner.

In a further embodiment it is provided that a third bearing is provided or arranged between an outer circumference of the first ring gear and the housing.

Alternatively or additionally, it is provided that a fourth bearing is provided or arranged between an outer circumference of the second ring gear and the housing.

In this way, great stability of the switchable transmission, in particular in the radial direction, can be achieved and, nevertheless, the first and second ring gears can run freely with respect to the housing when the clutches are switched accordingly. A particularly low friction between the respective outer circumference of the mounted ring gear and the housing can also advantageously be achieved in this way, as a result of which the efficiency of the transmission is improved.

The third bearing and / or the fourth bearing can, for example, be designed as plain bearings, ball bearings, roller bearings or needle bearings.

In a further development it is provided that the first planetary gear and the second planetary gear are formed in one piece. This advantageously has the effect that the assembly of the two planet gears can be produced particularly inexpensively and easily and that the transmission can thereby be designed to be particularly compact in the axial direction. This ensemble can, for example, be formed from the two planet gears as a monoblock without any axial spacing from one another.

Alternatively, it can be provided that the first planetary gear and the second planetary gear and the first planetary gear axle are formed in one piece. As a result, this ensemble of the two planetary gears and the planetary gear axle (which is also a shaft here) can advantageously be produced in a particularly inexpensive and simple manner. This also advantageously prevents the planet gears to be mounted on the planet gear axis from being mixed up. Finally, the axial geometry of the transmission can advantageously be adapted to structural requirements by means of the length of the planetary gear axis.

In a further advantageous embodiment variant, the number of teeth on the first planetary gears corresponds to the number of teeth on the second planetary gears.

The two alternative ensembles can, for example, be produced in a casting process or an injection molding process.

The switchable transmission further preferably comprises at least one belt drive. The belt drive is preferably arranged on the input shaft and connects the input shaft in particular to an electrical machine. Alternatively, a belt drive is additionally or solely arranged on the output shaft. The belt drive on the output shaft can, for example, connect or couple the output shaft to a shaft or axle of a wheel of a vehicle, in particular a vehicle trailer.

The belt drive can advantageously prevent overloading of the shiftable transmission from excessive torque loads. Because if the torque is too high, the belt drive can slip in the manner of a predetermined breaking point and thus relieve the load on the switchable gear.

The belt drive can also advantageously be designed as a belt drive, as a result of which a further gear ratio can be provided in addition to the two gears of the shiftable transmission. A translation can - only as an example - be in a range from 1: 1.2 to 1: 4. Other translations or reductions are also conceivable.

The present invention also relates to a trailer axle with a switchable transmission according to the invention and with an electrical machine which is set up to be operated as an electric motor or as a generator.

Such a trailer axle can - only for example - be a rigid connecting element (for example a hollow beam) between a left and right side of a trailer, at the free ends of which wheels can preferably be arranged directly or indirectly. The trailer axle can continue, for example have at each of their ends a spring element to which a wheel or a rim of the trailer can be attached. For example, such a spring element can be designed as a leaf spring or as a rocker arm, which is provided with a torsion spring, for example. Such a rocker can only be attached to the trailer axle in a spring-like manner by way of example.

In general terms, a suspension (e.g. designed as a torsion bar) can be arranged between the trailer axle and a trailer chassis.

It goes without saying that the trailer axle can have such a shiftable transmission on each side (viewed left / right with respect to the direction of travel). Each switchable gearbox can be provided with its own motor on the input shaft.

However, it is also possible that only a single electrical machine is provided, which is connected to the input shafts of two or more switchable transmissions.

Furthermore, an energy store is preferably provided which is (electrically) connected to the electrical machine. The energy store is set up to supply the electrical machine with electrical energy when it is operated as an electric motor and to store electrical energy when the electrical machine is operated as a generator.

The present invention also relates to a vehicle trailer with a trailer axle according to the invention. The vehicle trailer is, for example, a caravan or a trailer of a truck or another trailer of a car.

The vehicle trailer particularly preferably comprises at least one electrical consumer that is electrically connected to the electrical machine, in particular a refrigerator, an air conditioning system, a television, hot water preparation, a microwave, a hair dryer or a cooling unit (e.g. for a refrigerated trailer of a truck). The electrical consumer can be supplied with electrical energy directly from the electrical machine in generator mode or via one or more electrical (additional) energy stores.

An electrical connection between the electrical machine and the electrical consumers can be established indirectly, e.g. via an energy store and / or via an on-board network of the vehicle trailer, or directly.

It can be provided that an additional energy store of the vehicle trailer is connected to the electrical machine. As a result, this additional energy store can advantageously be charged in generator mode or, in maneuvering mode, the vehicle trailer can take the energy required for maneuvering directly from the additional energy store. An (electrical) connection to the towing vehicle or an external connection (e.g. a socket) is then advantageously no longer necessary - the vehicle trailer is advantageously autonomous in terms of energy.

A voltage converter, for example, can be arranged between the energy store and the trailer electrical system, which makes it possible to operate the energy store with a voltage level that differs from that of the trailer electrical system.

Figure list

• 1 eine schematische Darstellung eines schaltbaren Getriebes für eine Fahrzeugachse eines Fahrzeuganhängers gemäß einem bevorzugten Ausführungsbeispiel der Erfindung.

A preferred embodiment of the invention is described in detail below with reference to the accompanying drawing. In the drawing is:

• 1 a schematic representation of a shiftable transmission for a vehicle axle of a vehicle trailer according to a preferred embodiment of the invention.

Preferred embodiment of the invention

Referring to FIG 1 a switchable transmission 100 described in detail according to a preferred embodiment of the invention. The switchable transmission 100 is here - merely by way of example - arranged in or on a trailer axle of a vehicle trailer, with only one shaft here 18th is shown which can be connected to a wheel, for example, which can be attached to the trailer axle.

How out 1 can be seen is the switchable transmission 100 between the wave 18th and an electric machine 17th arranged. The electric machine 17th is with a control unit 16 connected, which also the switchable gear 100 controls or switches. Furthermore, there is the electrical machine 17th with an energy store 19th connected, for example a battery of a trailer electrical system, which can be operated with 12V, 24V, 36V, 48V, etc., for example.

1 shows schematically in section the switchable transmission 100 . The switchable transmission 100 includes a first planetary gear 11 and a second planetary gear 12th as well as a planet carrier 6th . How out 1 can be seen are the two planetary gears 11 , 12th arranged one after the other, that is, viewed along an axis XX, in series one after the other or one behind the other.

The first planetary gear 11 comprises a (first) sun gear 7th (hereinafter referred to simply as "sun gear"), first planetary gears 4th , as well as a first ring gear 3 .

The (first) sun gear 7th has a first number of teeth Z1 on, the first planetary gears 4th have second numbers of teeth Z2 and the first ring gear 3 has a third number of teeth Z3 on. In the cross section shown are two first planet gears 4th to recognize. However, it is also possible that only a single first planetary gear 4th is present or that more than two first planetary gears 4th are provided, for example three, four, five, six or even more first planetary gears 4th .

The second planetary gear 12th includes here second planet gears 5 and a second ring gear 13th . The second planetary gears 5 have a fourth number of teeth Z4 and the second ring gear 13th has a fifth number of teeth Z5 on. In the cross section shown are two second planet gears 5 to recognize. However, it is also possible that only a single second planetary gear 5 is present or that more than two second planetary gears 5 are provided, for example three, four, five, six or even more second planetary gears 5 .

The second planetary gear 12th has no sun gear here. The first planetary gears 4th are here - only by way of example - each on planetary gear axles 8th (or planetary gear shafts) attached. The planetary gear axles 8th are in or on the - here only as an example between the first and second planetary gears 4th , 5 arranged - planet carrier 6th mounted, in particular rotatably mounted.

The first ring gear 3 and the second ring gear 13th are freely rotatable in the housing 1 arranged.

The (first) sun gear 7th is with an input shaft 14th (first shaft) connected or on the input shaft 14th arranged.

How further from the 1 can be seen are the input shaft 14th (first wave) and an output shaft 15th (second shaft) arranged on the (here: common) axis XX.

The gear 100 furthermore has a planet carrier 6th on, with the first planet gears 4th and the second planetary gears 5 are rotatably connected to each other and rotatable on the planet carrier 6th are stored. In this embodiment, the first are planet gears 4th and the second planetary gears 5 each through a common planetary gear axle 8th coupled or connected to one another in a rotationally fixed manner. First planetary gear 4th , second planetary gear 5 and planetary gear axle 8th can be made in one piece, for example as a cast part or an injection-molded part. The planetary gear axis 8th is rotatable in the planet carrier 6th stored. The planet carrier 6th is here - only for example - viewed along the axial direction between first planet gears 4th and second planet gears 5 arranged. This arrangement is for the function of the transmission 100 not essential.

The case 1 encloses the switchable transmission and has a through opening 20th at a bottom of the housing 1 on (below in 1 ). The input shaft 14th is through the through hole 20th passed through. It can also be stored there, for example (not shown here for reasons of clarity).

One lid 2 (above in 1 ) closes the housing 1 and has a flange area 21 on, which is here for example cylindrical, in particular circular cylindrical. In the flange area 21 are a first camp 101 and a second warehouse 102 arranged which the output shaft 15th (second axis).

In principle, the output shaft could also 15th through the bottom of the case 1 be guided and the input shaft 14th through the lid 2 .

On the output shaft 15th is also the second ring gear 13th arranged. The second ring gear 13th is here only as an example in one piece or in one piece with the output shaft 15th educated.

The first planetary gear 11 and the second planetary gear 12th are inside the housing 1 basically arranged to rotate freely. Here is on the outer circumference of the first ring gear 3 e.g. a third warehouse 103 provided (between the housing 1 and the outer periphery of the first ring gear 3 ). On the outer circumference of the second ring gear 13th is for example a fourth camp 104 provided (between the housing 1 and the outer periphery of the second ring gear 13th ). The third and fourth camp 103 , 104 can for example be a plain bearing or a roller bearing, for example a needle bearing or a ball bearing.

The switchable transmission also includes 100 a first clutch K1 and a second clutch K2 . The first clutch K1 is a clutch between the first ring gear 3 and the case 1 is arranged. The first clutch K1 is set up here, the first ring gear 3 to couple with the housing on the one hand rotatably and on the other hand to release. Depending on the clutch position, this is the first ring gear 3 firmly to the housing 1 connected so that the first ring gear 3 can no longer rotate or, alternatively, is the first ring gear 3 not connected to the housing, so that the first ring gear 3 in the housing 1 can turn.

The second clutch K2 is between the planet carrier 6th and the case 1 intended. The second clutch K2 is set up the planet carrier 6th with the case 1 to couple or release in a non-rotatable manner. If thus the planet carrier 6th with the case 1 Is rotatably coupled, is the planet carrier 6th non-rotatably in the second planetary gear 12th held.

The shiftable transmission also includes the control unit 16 , which is set up, the first clutch K1 and the second clutch K2 to control. For the sake of clarity, the corresponding control lines are shown here 1 not shown. Furthermore, the control unit 16 also the electric machine 17th control as an electric motor or generator.

The switchable transmission 100 can now be operated in four operating modes, namely shifting into a first gear or a second gear, operating in a freewheeling mode or being locked.

To get into first gear (mode 1 ) becomes the first clutch K1 opened and the second clutch K2 closed. Thus is the first clutch K1 switched such that the first ring gear 3 is not connected to the housing. Thus, the first ring gear 3 rotate. The second clutch K2 is switched so that the planet carrier 6th firmly to the housing 1 connected is. Thus, the planet carrier can 6th do not rotate.

Is in this switching state, ie, first clutch K1 open, second clutch K2 closed, the (first) sun gear 7th Set in a rotary motion, the first ring gear rotates 3 through the one with the first ring gear 3 and the first sun gear 7th meshing first planetary gears 4th in the opposite direction of rotation of the first sun gear 7th (also the first planetary gears 4th turn in to the sun gear 7th opposite direction of rotation). Because the planet carrier 6th is recorded, it has no effect on the gear ratio. The planet carrier 6th can be used here, for example, as a bearing for the planetary gear axles 8th be viewed in the planet carrier 6th rotate.

wobei Z2 die Zähnezahl der ersten Planetenräder 4, Z3 die Zähnezahl des ersten Hohlrads 3, Z4 die Zähnezahl der zweiten Planetenräder 5 und Z5 die Zähnezahl des zweiten Hohlrads 13 ist.The second planet gears rotate at the same time 5 at the same angular speed and in the same direction of rotation as the first planetary gears 4th . The second planetary gears 5 in turn move the second ring gear 13th in a rotary movement with a direction of rotation that is that of the second planetary gears 5 is equivalent to. As a result, the second ring gear rotates 13th and thus the output shaft in a direction of rotation opposite to the input shaft. The drive takes place via the (first) sun gear 7th and output takes place via the second ring gear 13th . The following then applies to the translation in first gear: $$\text{i}1\left(\text{Z}\mathrm{1,}\text{Z}\mathrm{2,}\text{Z}\mathrm{4,}\text{Z}5\right)=\left(\text{Z}2*\text{Z}5\right)/\left(\text{Z}1*\text{Z}\mathrm{4th}\right),$$

where Z2 is the number of teeth on the first planetary gears 4th , Z3 the number of teeth of the first ring gear 3 , Z4 the number of teeth on the second planetary gears 5 and Z5 the number of teeth of the second ring gear 13th is.

With the following numbers of teeth of Z1 = 15, Z2 = 22, Z4 = 20, Z5 = 57 (as well as and Z3 = 60), the result is: $$\text{i}1=\left(\mathrm{22nd}*57\right)/\left(\mathrm{15th}*\mathrm{20th}\right)=\mathrm{4.18.}$$

For second gear (mode 2 ) become the two clutches K1 and K2 switched so that the first clutch K1 is closed and the second clutch K2 is open. So the first is ring gear 3 The planet carrier is non-rotatably connected to the housing 6th however, is in the housing 1 freely rotatable.
If the two clutches are in this switching state K1 and K2 the first sun gear 7th is set in a rotary motion, the first planet gears rotate 4th in the opposite direction.

The fixed connection between the first planetary gears 4th and second planet gears 5 causes the second planetary gears 5 move at the same angular speed and in the same direction of rotation as the first planetary gears 4th .

The planet carrier 6th rotates in the same direction as the (first) sun gear 7th .

• ■ zum einen wird das zweite Hohlrad 13 mittels der Verzahnung zu den zweiten Planetenrädern 5 in eine Drehbewegung versetzt, die in dieselbe Drehrichtung gerichtet ist wie die Drehrichtung der zweiten Planetenräder 5 (also entgegen der Drehrichtung des (ersten) Sonnenrads 7);
• ■ zum anderen wird das zweite Hohlrad 13 mittels der Verzahnung zum Planetenträger 6 in eine Drehbewegung versetzt, die in dieselbe Drehrichtung gerichtet ist wie die Drehrichtung des Planetenträgers 6 (also in dieselbe Drehrichtung des (ersten) Sonnenrads 7).

The movement of the second ring gear 13th is made up of two additional contributions:

• On the one hand, there is the second ring gear 13th by means of the toothing to the second planetary gears 5 set in a rotational movement which is directed in the same direction of rotation as the direction of rotation of the second planetary gears 5 (i.e. against the direction of rotation of the (first) sun gear 7th );
• ■ on the other hand is the second ring gear 13th by means of the toothing to the planet carrier 6th set in a rotary movement which is directed in the same direction of rotation as the direction of rotation of the planet carrier 6th (i.e. in the same direction of rotation of the (first) sun gear 7th ).

Thus, the second ring gear rotates at a speed of rotation (angular speed) and a direction of rotation that depends on how large the two proportions set out above are.

In this way, a very high gear ratio can be achieved, the higher the more similar the rotational speeds (angular speeds) of the second planetary gears 5 and the planet carrier 6th are.

For a ratio i2 in second gear, the following applies: $$\text{i2}\left(\text{<figure-callout id="1" label="Z" filenames="DE102020201411A1\_0005.png" state="{{state}}">Z</figure-callout>}\mathrm{1,}\text{<figure-callout id="2" label="Z" filenames="DE102020201411A1\_0005.png" state="{{state}}">Z</figure-callout>}\mathrm{2,}\text{<figure-callout id="3" label="Z" filenames="DE102020201411A1\_0005.png" state="{{state}}">Z</figure-callout>}\mathrm{3,}\text{<figure-callout id="4" label="Z" filenames="DE102020201411A1\_0005.png" state="{{state}}">Z</figure-callout>}\mathrm{4,}\text{Z}5\right)=\left(1+\text{<figure-callout id="3" label="Z" filenames="DE102020201411A1\_0005.png" state="{{state}}">Z</figure-callout>}3/\text{Z}1\right)/\left\{1-\left(\text{Z}\mathrm{4th}*\text{Z}3\right)/\left(\text{<figure-callout id="2" label="Z" filenames="DE102020201411A1\_0005.png" state="{{state}}">Z</figure-callout>}2*\text{Z}5\right)\right\}.$$

With the following numbers of teeth of Z1 = 15, Z2 = 22, Z3 = 60 as well as Z4 = 20 and Z5 = 57 (see also above for i1), the result is: $$\text{i}2\left(\mathrm{15,}22\mathrm{60,}\mathrm{20,}57\right)=116.11$$

If both the first clutch K1 as well as the second clutch K2 are open results in an idle (mode 3 ).

When the first clutch K1 and the second clutch K2 both are closed, are the first ring gear 3 and the planet carrier 6th both rotatably with the housing 1 connected. This locks the shiftable transmission. This mode can be used as a parking brake and / or as theft protection (mode 4th ).

Thus, through the clever arrangement of two planetary gears 11 , 12th in series a high spread of the translations are made possible in a cost-effective and very space-saving manner. This wide spread of the gear ratios is necessary for a maneuvering operation (low speed requirement, high torque requirement) and also a recuperation operation (high speed available on the output shaft 15th (second axis)) of the electrical machine 17th or to enable overrun operation during an overland journey. In particular, by simply switching the first and second clutch K1 and K2 a desired high spread of the translations can be achieved. The first clutch K1 and / or the second clutch K1 can only be designed as a claw clutch or as a friction clutch by way of example.

The two clutches K1 , K2 can also be designed differently.

For the construction of the first clutch K1 and / or the second clutch K2 can, for example, a (not shown here) rotatably in the housing 1 mounted and axially with respect to the housing 1 Slidable shift sleeve may be provided, the first clutch K1 and / or the second clutch K2 are switchable by means of the shift sleeve. The shift sleeve can, for example, have internal teeth, the internal teeth, depending on the switching position, in particular with external teeth on the first ring gear 3 and / or with external teeth on the planet carrier 6th is positively connected or not connected. In this way, both clutches can be implemented with just a single component and thus all four switching states or modes.

It should be noted that the fourth mode, which relates to the completely locked transmission, for example also by locking the input shaft 14th can be achieved. Furthermore, it is also possible that a further clutch on the second ring gear 13th is arranged to the second ring gear 13th with the case 1 to couple or release in a non-rotatable manner.

Thus, according to the invention, a trailer axle can also be provided (not shown here) which is in connection with an electrical machine 17th , which can work as an electric motor and as a generator, can be maneuvered in a simple manner and in which, when the trailer is being pulled, the electric machine can also be operated as a generator at correspondingly high speeds. The necessary high spread of the gear ratios for the different requirements of the electrical machine can be achieved by the switchable transmission 100 will be realized.

The desired translation (if it is not already realized by the gearbox alone) can also be achieved by providing an additional belt drive or chain drive, which is designed as a belt drive or chain drive. For example, this belt drive or chain drive can be arranged on the input shaft or on the output shaft or connected to it (indirectly or directly).
In addition, a predetermined breaking point or a slip clutch can be provided between the electric motor or the electric machine and the switchable transmission, which prevents the switchable transmission from being damaged by suddenly or permanently occurring torque.

In addition, a predetermined breaking point or a slip clutch can be provided between an element connected to the output shaft (e.g. a wheel attached to a trailer axle) and the shiftable gearbox, which prevents the shiftable gearbox from being damaged by suddenly or permanently occurring torque.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 1225090 A2 [0003]

Claims (15)

Shiftable transmission, comprising: - a housing (1), - A first planetary gear (11) with a sun gear (7), a first ring gear (3) and at least one first planet gear (4), - A second planetary gear (12) with a second ring gear (13) and at least one second planetary gear (5), - wherein the second planetary gear (12) in particular has no sun gear; - wherein the first ring gear (3) and the second ring gear (13) are arranged freely rotatable in the housing (1); - wherein the sun gear (7) is connected to an input shaft; - A planet carrier (6); - wherein the first planet gear (4) and the second planet gear (5) are connected to one another in a rotationally fixed manner and are rotatably mounted on or in the planet carrier (6); - A first clutch (K1) which is provided between the first ring gear (3) and the housing (1) and is designed to couple or release the first ring gear (3) with the housing (1) in a rotationally fixed manner, - A second clutch (K2) which is provided between the planet carrier (6) and the housing (1) and is designed to couple or release the planet carrier (6) with the housing (1) in a rotationally fixed manner, - an output shaft (15) which is connected to the second ring gear (13), - In particular a control unit (16) which is set up to control the first clutch (K1) and the second clutch (K2). Gearbox after Claim 1 , the first planetary gear (4) and the second planetary gear (5) having a common planetary gear axle (8), the first planetary gear (4) and the second planetary gear (5) being non-rotatably connected to the planetary gear axle (8), the planetary gear axle (8) is rotatably mounted in the planet carrier (6). Gearbox after Claim 1 , wherein the output shaft (15) is mounted in the housing (1), in particular in a cover (2) or a base of the housing (1), which is in particular with a first bearing (101) and / or with a second bearing (102) is designed. Transmission according to one of the preceding claims, wherein the input shaft (14) and the output shaft (15) are arranged on a common axis (X-X). Transmission according to one of the preceding claims, wherein the output shaft (15) is formed in one piece with the second ring gear (13). Transmission according to one of the preceding claims, wherein the first clutch (K1) is a friction clutch and / or wherein the second clutch (K2) is a friction clutch. Transmission according to one of the preceding claims, wherein the first clutch (K1) is a claw clutch and / or wherein the second clutch (K2) is a dog clutch. Transmission according to the preceding claim, wherein a non-rotatably mounted in the housing (1) and axially displaceable with respect to the housing (1) is provided, wherein the first clutch (K1) and / or the second clutch (K2) can be shifted by means of the shift sleeve, the shift sleeve in particular having internal teeth, the internal teeth being positively connected, depending on the switching position, in particular with external teeth on the first ring gear (3) and / or with external teeth on the planet carrier (6). Transmission according to one of the preceding claims, wherein a third bearing (103) is provided between an outer circumference of the first ring gear (3) and the housing (1) and / or wherein a fourth bearing is provided between an outer circumference of the second ring gear (13) and the housing (104) is provided. Transmission according to one of the preceding claims, wherein the first planet gear (4) and the second planet gear (5) are formed in one piece, or wherein the first planet gear (4) and the second planet gear (5) and the first planet gear axle (8) are formed in one piece. Transmission according to one of the preceding claims, wherein a belt drive is arranged on the input shaft (14) and / or on the output shaft (15). Trailer axle, having a switchable transmission (100) according to one of the preceding claims and an electric machine (17) which is set up to be operated as an electric motor or as a generator. Trailer axle according to the preceding claim, further comprising an energy store (19) which is electrically connected to the electrical machine (17). Vehicle trailer comprising a trailer axle according to one of the two preceding claims. Vehicle trailer according to the preceding claim, wherein an electrical consumer of the vehicle trailer is electrically connected to the electrical machine (17) of the trailer axle and / or wherein an additional energy store of the vehicle trailer is connected to the electric machine (17).

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