Power-splitting transmission, method for operating a power-splitting transmission, and vehicle equipped with a power-splitting transmission

Abstract

The present invention comprises: a first mechanical branch (16) comprising a planetary gear train device (18) having a drive shaft (12); two or more sun gears (Z1, Z1'); a first ring gear (Z3); and a planetary carrier (20) having a double planetary gear (Z2, Z2') disposed on top that meshes with the sun gears (Z1, Z1') and the first ring gear (Z3); - at least one of the sun gears (Z1) is coupled to the drive shaft (12); and a continuously adjustable second branch (22) that can be at least partially connected to the first mechanical branch (16) through the planetary gear train device (18) and comprises two or more adjustable hydraulic units (H1, H2), wherein the hydraulic units can be energetically coupled to each other and each can be operated as a motor (M) or a pump (PU) in two directions. The present invention relates to a power branching type transmission (30) having an output shaft (24) that can be coupled to a drive shaft (12) through a first mechanical branch (16) and a second branch (22), wherein a planetary reverse gear device (15) is assigned to the planetary gear train device (18), and the rotational direction of the first mechanical branch (16) can be reversed by the planetary reverse gear device. Furthermore, the present invention relates to a method for operating a power branching type transmission (30) and a vehicle equipped with a power branching type transmission (30).

Description

Technology Field

[0001] The present invention relates to a power branching type transmission having: a first mechanical branch comprising a planetary gear train device having a drive shaft; two or more sun gears; a first ring gear; and a planetary carrier having a double planetary gear disposed thereon that meshes with the sun gear and the first ring gear, wherein at least one of the sun gears is coupled to the drive shaft; a second branch that is continuously adjustable and can be at least partially connected to the first mechanical branch through the planetary gear train device and includes two or more adjustable hydraulic units, wherein the hydraulic units can be energetically coupled to each other and can each be operated as a motor or pump in two directions; and an output shaft that can be coupled to the drive shaft through the first mechanical branch and the second branch. A planetary reversing gear device is assigned to the planetary gear train device, and the rotational direction of the first mechanical branch can be reversed by the planetary reversing gear device.

[0002] In addition, the present invention relates to a method for operating a power branching transmission and an automobile equipped with a power branching transmission. Background Technology

[0003] When using an internal combustion engine in a vehicle, it is necessary to combine the engine with a transmission to enable the engine to operate at an advantageous operating point over a wide speed range. For example, agricultural tractors can be referenced in this regard; in the case of this tractor, the field speed is partially only 0.4 km / h for manual planting applications, whereas a speed of 60 km / h or more is desirable for movement between the field and agricultural work. Since the operation of the motor is not consistently guaranteed within its optimal range in the case of a transmission with a given number of gears, the need to achieve continuous changes in gear ratios to provide vehicle speed regardless of motor speed arose very early on.

[0004] To this end, WO 2006 / 042434 A1 discloses a power-splitting transmission suitable for use in agricultural vehicles, wherein a stepped planetary gear unit is provided between a drive shaft and an output shaft coupled to an internal combustion engine to divide the power present in the drive shaft into a mechanical power split and a hydraulic power split. The hydraulic power split is formed by two identical hydrostatic axial piston machines hydraulically connected to each other, which can optionally operate as a pump or a motor and rotate within a predetermined pivot angle range. The two hydrostatic axial piston machines are hydraulic units for covering different travel ranges or travel stages, and can each be connected to the drive shaft or the stepped planetary gear in different ways through two clutches. The two hydraulic units are configured as a wide-angle hydrostatic drive.

[0005] Since the above literature describes in detail the operation method of a power-splitting type transmission and a wide-angle hydrostatic drive unit used in such a transmission, the literature can be used as a reference for the professional knowledge of a person skilled in the art.

[0006] However, the above-mentioned power-splitting transmission has the disadvantage of low reverse driving efficiency. Therefore, WO 2016 / 102572 A1 provides a reversing stage between the drive shaft and the output shaft for changing between the forward driving range and the reverse driving range. In this case, the reversing stage reverses the rotational direction of the sun gear of the ring gear and the rotational direction of the carrier shaft of the planetary gear train device when changing between the forward driving range and the reverse driving range, or maintains both constant. That is, when changing between the forward driving range and the reverse driving range, the relative rotational directions of the sun gear, ring gear, and carrier shaft are maintained in the same directionality, so that individual components of the planetary gear train device are not reversed, and other components are not reversed, thereby eliminating a situation in which rotational direction overlap occurs within the planetary gear train device when changing between the forward driving range and the reverse driving range. At this time, the reverse stage includes two clutch elements between the output side of the planetary gear train device and the output shaft, and in the forward driving range, torque is transmitted through the first clutch element, and in the reverse driving range, torque is transmitted through the second clutch element. The problem to be solved

[0007] The objective of the present invention is to provide a power-splitting transmission that has a simplified structure and does not require a clutch on the output side of a planetary gear train device. Another objective is to provide a method for operating the power-splitting transmission for a forward driving range as well as a reverse driving range, and to provide an automobile equipped with the power-splitting transmission. means of solving the problem

[0008] The above problem is solved by a power-splitting transmission having the features of claim 1, a method for operating a power-splitting transmission having the features of claims 13 and 15, and a vehicle having the features of claim 17. Preferred embodiments having preferred improvements of the present invention are specified in dependent claims.

[0009] The power split type transmission mentioned in the introduction is characterized by the fact that the rotational direction of the components of the planetary gear train device, which is equipped with a sun gear, a ring gear, and a carrier shaft, is maintained for both the forward and reverse driving ranges, and that the output shaft is driven in the correct rotational direction by using a planetary reverse gear device to reverse the rotational direction of the planetary gear train device when changing between the forward and reverse driving ranges. To achieve this, there is no need to use a clutch, which reduces the complexity of the power split type transmission, simplifies application, and saves installation space, thereby realizing a simple and compact power split type transmission in which the reverse driving range is driven in the same manner as the forward driving range without generating reactive power.

[0010] If a planetary reverse gear device has an axially adjustable shift sleeve, and at one axial position of the shift sleeve, the rotational direction of the planetary carrier can be directly transmitted to a first mechanical branch, and at another axial position of the shift sleeve, the rotational direction of the planetary carrier can be supplied to the first mechanical branch in the opposite direction, then miniaturization of the structure is promoted, and in this case, rotation of the shift sleeve relative to the transmission housing at one of the axial positions is blocked.

[0011] In addition, it is also preferable for the shift sleeve to be formed as a reversing ring gear equipped with a reversing planetary gear having an odd number of assigned gear wheels, in which case the radial inner gear wheel of the shift sleeve is fixedly connected to rotate integrally with the first mechanical branch by a coupling shaft. Thus, a very compact structure is created, and in this case, at one axis position of the shift sleeve, the shift sleeve is prevented from rotating by being fixed to the transmission housing, and thus the gear wheel in contact with the shift sleeve formed as a reversing ring gear runs on the reversing ring gear, and accordingly, the direction of rotation is reversed compared to the other case where the reversing ring gear rotates together with the planetary gear train device without rotational interruption at another axis position.

[0012] Additionally, a configuration is provided in which a coupling shaft is formed as a hollow shaft and surrounds a journal shaft connected to a drive shaft.

[0013] Additionally, a configuration is provided in which the first mechanical branch is connected downstream of the planetary reverse gear unit in the direction of power flow, and the second branch is connected to or can be connected to the summing shaft connected to the output shaft through the first clutch. In this way, the use of the hydrostatic branch of the power-branching transmission is ensured, and it should be noted that in this case, the power of the mechanical branch and the power of the hydrostatic branch are combined again through the summing shaft. In this case, a clutch is assigned to the hydrostatic branch in the conventional manner, but on the output side of the planetary gear train unit, a clutch is unnecessary to enable power flow to the summing shaft due to the planetary reverse gear unit; that is, since the power transmission chain between the summing shaft and the output shaft is formed without clutch elements, a very compact structure is created in this area as well.

[0014] In this case, the first mechanical branch is connected to the summing shaft via an odd number of gear wheels at the output side of the coupling shaft. Additionally, it is preferable that a second clutch be assigned to the second branch, because this allows for the provision of a second driving range in which power is supplied to the summing shaft only through a planetary gear device.

[0015] In a preferred manner, the first clutch is formed as a claw clutch assigned to the summing shaft for disengageable interaction with the hydrostatic shaft of the second hydraulic unit.

[0016] When the second clutch is assigned to the hydrostatic shaft of the second hydraulic unit, and the second clutch is formed as a double claw clutch so that the second hydrostatic unit interacts with the sun gear through the first gear transmission in the first closed position and interacts with the sun gear through the second gear transmission in the second closed position, there are equivalent conditions for the forward driving range and the reverse driving range, and the forward driving range and the reverse driving range can each operate at the same speed range in two stages.

[0017] In the second stage, to expand the usage range of the power-dividing transmission, an additional gear stage may be provided by placing an additional gear stage between the gear wheel assigned to the coupling shaft and the adjacent gear wheel, wherein the first auxiliary gear wheel assigned to the coupling shaft is coupled through two clutches and the second auxiliary gear wheel and the third auxiliary gear wheel are detachably coupled to adjacent gear wheels.

[0018] A method for operating such a power-dividing transmission is characterized in that, in the forward driving range, the shift sleeve is adjusted to an unfixed shaft position so as to rotate integrally with respect to the transmission housing, the first hydraulic unit is coupled to the ring gear through a gear wheel (Z5) and a gear wheel (Z4) on the outer rim of the ring gear, the second hydraulic unit is coupled to the summing shaft through a first clutch, a gear wheel (Z9), and a gear wheel (Z10), the first hydraulic unit is pivoted in a positive angle range in the first pivot direction from a pivot position where the pivot angle is 0° and operates as a pump, and the second hydraulic unit operates as a motor. In this configuration performing the method steps, starting in the forward direction is performed in the first stage, and the ratio transmitted hydrostatically is initially 100%, and then decreases to 0% until the first hydraulic unit reaches the maximum pivot angle.

[0019] In this case, it is also possible to perform method steps in which the first hydraulic unit operates as a motor and the second hydraulic unit operates as a pump in the second stage of the forward driving range, wherein the second hydraulic unit is coupled to the sun gear through the second clutch and the first gear transmission and pivots from a pivot position of 0° to a negative angle range.

[0020] Additionally, a method of operating a power-divided transmission is provided in which the shift sleeve is adjusted to a fixed axial position so that the shift sleeve rotates integrally with the transmission housing during reverse driving range, wherein the first hydraulic unit is operated as a pump and the second hydraulic unit is operated as a motor, and the rotational direction of the second hydraulic unit is reversed by pivoting the first hydraulic unit from a pivot position of 0° to a negative angle range in the direction of the second pivot. Accordingly, torque is transmitted to the summing shaft in the correct rotational direction not only through the first mechanical branch but also through the second hydrostatic branch.

[0021] Regarding the reverse driving range, it is possible to perform method steps in which the first hydraulic unit operates as a motor and the second hydraulic unit operates as a pump in the second stage of the reverse driving range, in which case the second hydraulic unit is coupled to the sun gear through the second clutch and the second gear transmission and pivots from a pivot position of 0° to a negative angle range.

[0022] As a result, since the rotational direction of the mechanical power branch is reversed by the planetary reverse gear mechanism, the forward driving range and the reverse driving range are formed equally in the power branch type transmission. The two driving ranges are formed to have two driving stages each, which can be further supplemented by another gear stage if necessary. In the first stage, the hydrostatic power component is 100% at the starting point and drops to 0% as the speed increases, not only in forward driving but also in reverse driving, and the hydraulic power branch and the mechanical power branch are joined through a summing shaft. In the second stage, the hydraulic power branch and the mechanical power branch are joined by the planetary gear train mechanism, in which case the hydraulic power component is 0% to 29%.

[0023] The aforementioned advantages and effects similarly apply to vehicles equipped with the above-mentioned type of power-splitting transmission.

[0024] The features and feature combinations mentioned in the preceding description and the features and feature combinations mentioned in the following description of the drawings and / or illustrated individually in each drawing may be used not only in the specified combinations but also in other combinations or individually, provided that there is no departure from the scope of the present invention. Accordingly, embodiments that may be revealed and generated by separate feature combinations derived from the described embodiments, even if not explicitly illustrated or described in the drawings, should also be deemed to be included and disclosed in the present invention.

[0025] Further advantages, features, and details of the present invention are revealed from the claims, the following description of preferred embodiments, and the drawings. Brief explanation of the drawing

[0026] Figure 1 is a model representation of a power-dividing transmission. Figure 2 is a top view of the structural configuration of the model representation of the power-dividing transmission shown in Figure 1. FIG. 3 is a side view of the power branching transmission of FIG. 2, partially cut and illustrated in the area of ​​the planetary gear train device. FIG. 4 is a drawing taken from the direction of arrow (IV) in FIG. 2, partially cut and illustrated in the area of ​​the second ring gear of the planetary reverse gear device. FIG. 5 is a drawing taken from the direction of arrow (V) in FIG. 2, partially cut and illustrated in the area of ​​the differential lock assigned to the output shaft. FIG. 6 is a drawing corresponding to FIG. 1, including the corresponding pivot angles of two hydraulic units for starting in a forward driving range; and is a drawing that symbolically illustrates the flow of power within a closed power transmission chain, including a dashed line for power at the transmission input having a drive shaft, a dotted line for power transmitted hydraulically, a dotted line for power transmitted mechanically, and a solid line for power at the transmission output having an output shaft. FIG. 7 is a diagram illustrating the starting process from the starting position shown in FIG. 6 using symbols in partial drawings a), b), and c). FIG. 8 is a drawing corresponding to FIG. 6 of the state according to FIG. 7c) regarding the forward driving range while transitioning from the first stage to the second stage. FIG. 9 is a drawing corresponding to FIG. 7, having the initial state in a) when transitioning from the first stage. FIG. 10 is a drawing corresponding to FIG. 6, including corresponding pivot angles of two hydraulic units for starting in the reverse driving range, and a drawing illustrating the flow of power in a closed power transmission chain, including a shift sleeve of a planetary reverse gear device shifted relative to FIG. 6 for the reverse driving range. FIG. 11 is a drawing corresponding to FIG. 7 for the starting process in the reverse direction. FIG. 12 is a drawing corresponding to FIG. 9 for a reverse driving range having a starting state in a) when switching from the first stage to the second stage. FIG. 13 is a drawing corresponding to FIG. 6, which symbolically illustrates the power flow in the state according to FIG. 12b). Figure 14 is a transmission diagram of the power branching type transmission shown in Figure 1. FIG. 15 is a drawing corresponding to FIG. 14, including an additional gear stage with two multi-plate clutches to provide another stage. FIG. 16 is a drawing corresponding to FIG. 9b) with respect to the forward driving range, including an additional gear stage as part drawing a); and a drawing corresponding to FIG. 9c) including an additional gear stage as part drawing b). FIG. 17 is a drawing corresponding to FIG. 6, which symbolically illustrates the power flow within a closed power transmission chain according to FIG. 16a. FIG. 18 is a drawing corresponding to FIG. 12b) with respect to the reverse driving range, including an additional gear stage as part drawing a); and a drawing corresponding to FIG. 12c) including an additional gear stage as part drawing b). FIG. 19 is a drawing corresponding to FIG. 6, which symbolically illustrates the power flow within a closed power transmission chain according to FIG. 18a. FIG. 20 is a drawing corresponding to FIG. 1 of an embodiment having a first clutch and a second clutch formed as a multi-plate clutch. Figure 21 is a diagram showing the hydrostatic power component (dashed line) and efficiency as a function of speed. Specific details for implementing the invention

[0027] FIG. 1 shows a three-dimensional model drawing of a power-branching transmission (30) coupled to a combustion engine by a self-driving shaft (12), symbolized by a piston (10) connected to a crankshaft (11). The connection between the internal combustion engine and the driving shaft (12) can also be made through a torsion damper not shown in the drawing and a cardan shaft not shown.

[0028] The drive shaft (12) is connected to a journal shaft (13) that extends through the power splitter transmission (30), and another component can be driven by this journal shaft. For example, if the power splitter transmission (30) is used in a vehicle designed as an agricultural tractor, a pump for the working hydraulic system and an additional pump for steering can be driven through the journal shaft (13); likewise, other devices can be driven.

[0029] The power branching type transmission (30) has a planetary gear train device (18) equipped with a large sun gear (Z1) and a small sun gear (Z1'). Additionally, there are double planetary gears (Z2 and Z2'), a first ring gear (Z3), and a planetary carrier (P). A first mechanical branch (16) passes through this planetary gear train device (18), and through this mechanical branch, power provided from an internal combustion engine via a drive shaft (12) can be supplied to a summing shaft (14) and from there to an output shaft (24).

[0030] FIGS. 2 to 5 show structural embodiments of the schematic diagram of the power branching type transmission (30) shown in FIG. 1.

[0031] Here, as a feature of the power-splitting type transmission (30), a planetary reverse gear unit (15) is provided on the output side of the planetary gear train unit (18) for simple switching between the forward driving range (V) and the reverse driving range (R). The rotational direction of the first mechanical branch (16) can be reversed by this planetary reverse gear unit (15). The planetary reverse gear unit (15) includes an axially adjustable shift sleeve (Z23) formed as a reverse ring gear, which directly transmits the rotational direction of the planetary carrier (P) at the first axial position to the reverse planetary gears (Z22, Z21, Z20), and the reverse planetary gears are connected to the summing shaft (14) in a forced coupling manner by three gear wheels (Z11, Z12 and Z13) in the first mechanical branch (16).

[0032] In the second axis position, the shift sleeve (Z23) is directly or indirectly blocked from rotation with respect to the transmission housing (17) of the power-dividing transmission (30), so that the rotational direction of the planetary carrier (P) in the axis position is reversed and acts in a reversed rotational direction with respect to the summing shaft (14). To this end, the shift sleeve (Z23) is equipped with reverse planetary gears (Z20, Z21, Z22) having an odd number of assigned gear wheels, in which case the radial inner gear wheel (Z20) is fixedly connected to rotate integrally with the gear wheels (Z11, Z12, Z13) by a coupling shaft (19) having a first mechanical branch (16). The coupling shaft (19) is formed as a hollow shaft and surrounds the journal shaft (13).

[0033] The power branching transmission (30) also has two hydraulic units (H1 and H2) forming a continuously adjustable hydraulic second branch (22) of the power branching transmission (30). The two hydraulic units (H1, H2) are hydraulically connected to each other through a high-pressure line not shown.

[0034] The hydraulic units (H1 and H2) are formed by a bent-axis type wide-angle hydrostatic drive unit in which a cylinder block (20) having a piston (21) inside can be pivoted by any pivot angle from the axis of a related hydrostatic shaft (23) toward one side. The basic structure and operation method of the wide-angle hydrostatic drive unit are described in WO 2006 / 042434 A1 and are known therefrom.

[0035] When the cylinder block (20) is rotated around its individual axis through the hydrostatic shaft (23) and the synchronization shaft at a constant pivot angle other than 0°, each piston (21) passes through a complete stroke cycle per rotation.

[0036] At this time, driving is performed through the hydrostatic shaft (23), and when the hydraulic medium is sucked in by the piston (21) moving outside the cylinder bore and pushed out by the piston (21) moving inside the cylinder bore, the hydraulic unit (H1, H2) can operate as a hydraulic pump (PU). At this time, the larger the pivot angle, the greater the pumping capacity as volume per rotation.

[0037] When each cylinder is pressurized with a hydraulic medium and the resulting rotational motion is removed from the hydrostatic shaft (23), the hydraulic unit (H1, H2) can also operate as a hydraulic motor (M). At this time, the larger the pivot angle, the greater the torque.

[0038] The operation method of the hydraulic units (H1, H2) is also shown in the drawings, and the same applies to the shift positions (V, R) of the planetary reverse gear unit (15) and the shift positions (K2V and K2R) of the double claw clutch (K2V / K2R).

[0039] The drive shaft acts on the first hydraulic unit (H1) through the gear wheel (Z4) and gear wheel (Z5) on the outer rim of the ring gear (Z3).

[0040] The second hydraulic unit (H2) is coupled to the summing shaft (14) through the first clutch (K1) and gear wheels (Z9 and Z10) within the first forward driving range (V) and reverse driving range (R), and the summing shaft is connected to the output shaft (24) through the gear wheels (Z15 and Z14), and in this embodiment, the output shaft is used to drive the rear axle (HA) and can also be used to drive the front axle (VA) through the third clutch (K3).

[0041] In the embodiment illustrated in FIGS. 1 to 19, the first clutch (K1) is formed as a claw clutch assigned to the summing shaft (14) for disengageable interaction with the hydrostatic shaft (23) of the second hydraulic unit (H2). Additionally, the second clutch (K2) is assigned to the hydrostatic shaft (23) of the second hydraulic unit (H2) and is formed as a double claw clutch (K2V / K2R) so that in the first closed position (K2V) assigned to the forward driving range, the hydrostatic unit (H2) interacts with the sun gear (Z1') through the first gear transmission (Z6, Z7), and in the second closed position (K2R) assigned to the reverse driving range, it interacts with the sun gear (Z1') through the second gear transmission (Z7', Z7", Z6', Z6).

[0042] FIGS. 15 to 19 show that between the gear wheel (Z11) assigned to the coupling shaft (19) and the adjacent gear wheel (Z13), an additional gear stage (31) may be arranged to connect the first auxiliary gear wheel (Z11') assigned to the coupling shaft (19) through two clutches (KS, KL) and to detachably connect the second auxiliary gear wheel (Z11'S) and the third auxiliary gear wheel (Z11L) to the adjacent gear wheel (Z13).

[0043] In the embodiments illustrated in FIGS. 1 to 19, the clutches (K1 and K2) are formed as claw clutches and the clutch (K3) is formed as a multi-plate clutch, while FIG. 20 shows an example of using a multi-plate clutch for the clutches (K1 and K2), which is also possible in principle but is associated with a loss of the second stage for the reverse driving range (R).

[0044] Accordingly, the second hydraulic unit (H2) can be coupled to the summing shaft (14) through the first clutch (K1), and when the first clutch (K1) is open, it can be coupled to the planetary gear train device (18) by the second clutch (K2) through the first gear transmission (Z6, Z7) or the second gear transmission (Z7', Z7', Z6', Z6') and the small sun gear (Z1').

[0045] Below, possible operating modes of a power branching type transmission (30) having the above-described structure are explained.

[0046] One of the possible operating modes is an active stop state in which the summing shaft (14) and the output shaft (24) through it are blocked and a kind of "parking brake" is present. To this end, the second hydraulic unit (H2) is fully pivoted as shown in FIG. 1, while the first hydraulic unit (H1) has a pivot angle of 0°. By having the first hydraulic unit (H1) act as a pump (PU) and the second hydraulic unit (H2) act as a motor (M), the desired blockage is achieved through the second hydraulic unit (H2) and the first clutch (K1).

[0047] The forward driving range (V) is described with reference to FIGS. 6 and FIGS. 7. Initially, when the vehicle equipped with the power-splitting transmission (30) is in a stationary state, the second hydraulic unit (H2) is fully pivoted and the first hydraulic unit (H1) has a pivot angle of 0°. The first hydraulic unit (H1) acts as a pump (PU), and the second hydraulic unit (H2) acts as a motor (M). At startup, the first hydraulic unit (H1) is pivoted from 0° to a positive angle range, counterclockwise in the illustrated embodiment, and to a maximum pivot angle of 45° in the illustrated embodiment. The hydrostatic power from the first hydraulic unit (H1) is supplied to the second hydraulic unit (H2), which operates as a motor (M), and is guided to the summing shaft (14) through the first clutch (K1), in which case power is likewise mechanically supplied to the summing shaft through the first mechanical branch (16) directly to the planetary carrier (P) and reverse planetary gears (Z20, Z21, Z22) (Fig. 6). In Fig. 6, the power flow within the closed power transmission chain is illustrated by symbols, where the dashed line represents power at the transmission input having the drive shaft, the dotted line represents power transmitted hydraulically, the dotted line represents power transmitted mechanically, and the solid line represents power at the transmission output having the output shaft. This assignment is maintained in the remaining similar illustrations.

[0048] FIG. 7b illustrates the state in which the first hydraulic unit (H1) has reached the maximum pivot angle, and accordingly, the second hydraulic unit (H2) is pivoted again to a pivot angle of 0° (Fig. 7c), thereby stopping the first hydraulic unit (H1). The clutches (K1 and K2) operate synchronously to become unloaded, and accordingly, the first clutch (K1) opens and the second clutch (K2) closes. As a result, the second hydraulic unit (H2) is coupled to the small sun gear (Z1') of the planetary gear train device (18) via the gear transmission (Z6, Z7). The power flow within the power transmission chain can be seen in FIG. 8.

[0049] As the second hydraulic unit (H2) is pivoted further in the opposite direction to a negative angle range, the flow direction of the hydraulic units (H1, H2) is changed, and the second hydraulic unit (H2) acts as a pump (PU) to drive the first hydraulic unit (H1), thereby changing the forward driving range (V) to the second stage. The hydrostatic power and mechanical power are combined in the planetary gear train device (18), and the power transmitted hydrostatically increases. When the second hydraulic unit (H2) is fully pivoted, the first hydraulic unit (H1) is pivoted back to 0° (Fig. 9C), and as a result, the second hydraulic unit (H2) is almost at a standstill, and power transmission proceeds almost purely mechanically through the first mechanical branch (16).

[0050] In FIG. 21, the hydrostatic power component (HL) is shown as a function of speed. At startup, the hydrostatic power component (HL) is 100%, then drops almost linearly to 0%, at which point the transition from the first to the second stage of the forward driving range (V) occurs, and the hydrostatic power component (HL) increases again to approximately 29%, and after this maximum value, it can be seen that it drops again until power transmission is finally achieved purely mechanically. FIG. 21 also shows an efficiency (η) that remains almost constant at a high level over almost the entire speed range.

[0051] That is, for the first and second stages of the forward driving range (V), the power flow (25) within the power transmission chain is illustrated in FIG. 6 and FIG. 8, wherein FIG. 6 shows a constellation at startup in which hydrostatic power is supplied from the second hydraulic unit (H2) through the first clutch (K1) to the summing shaft (14), and mechanical power is transmitted from the drive shaft (12) through the planetary gear train device (18) to the summing shaft (14). FIG. 8 shows a transition to the second stage of the forward driving range (V), in which the generated hydrostatic power is likewise supplied to the planetary gear train device (18) and from there to the summing shaft (14).

[0052] FIG. 11 shows the initial situation when starting from a stationary state in the reverse driving range (R) in partial drawing a). For the reverse driving range (R), the rotational direction of the planetary carrier (P) is reversed by fixing the reversing ring gear as a shift sleeve (Z23) to rotate integrally with respect to the transmission housing (17) in the second axis position. The second hydraulic unit (H2) operates as a motor (M) and is fully pivoted, while the first hydraulic unit (H1) acts as a pump (P) and is pivoted clockwise from an initial position of 0° to -45°. Conversely, due to the pivoting direction of the first hydraulic unit (H1) into a negative angle range, the rotational direction of the second hydraulic unit (H2) is reversed and supplied to the summing shaft (14) through the first clutch (K1) having a corresponding rotational direction, and the summing shaft receives mechanical power components by the planetary reversing gear device (15) having a likely reversed rotational direction.

[0053] In this case, the power flow can be seen in FIGS. 10 and FIGS. 13, which show that the joining of power components in the forward driving range (V) and the reverse driving range (R) is basically performed the same way compared to FIGS. 6 and 8, and FIG. 13 shows the use of the second gear transmission (Z7', Z7'', Z6', Z6) through the double claw clutch (K2V / K2R) in position (K2R).

[0054] FIG. 15 shows an embodiment in which, to extend the range of use, an additional gear stage (31) equipped with two clutches (KS and KL) via a coupling shaft (19) is used in the second stage, more precisely for both the forward driving range (V) and the reverse driving range (R). At the end of the second stage, the clutch (KL) is open and the clutch (KS) is closed; during the time of transition from the clutch (KL) to the clutch (KS), the first hydraulic unit (H1) is pivoted from 0° to 45°. When the clutches (KL and KS) reach synchronous speed, the first hydraulic unit (H1) is pivoted back to 0°.

[0055] FIGS. 16 and 17 illustrate the use of an additional gear stage (31) in the forward driving range (V). At the end of the second stage, clutch (KL) is open and clutch (KS) is closed; in this case, the first hydraulic unit (H1) is pivoted from 0° to 45° while transitioning from clutch (KL) to clutch (KS). As soon as clutch (KS) and clutch (KL) reach synchronous speed, the first hydraulic unit (H1) is pivoted back to 0°. Since the second hydraulic unit (H2) is fully pivoted, this hydraulic unit is in a nearly stationary state, and power transmission is almost purely mechanical (Fig. 17).

[0056] FIGS. 18 and 19 show the conditions when using an additional gear stage (31) in the reverse driving range (R) at the end of the second stage, where it should be noted that the pivot direction of the first hydraulic unit (H1) is reversed compared to the forward driving range (V). Explanation of the symbols

[0057] 10: Piston 11: Crankshaft 12: Drive shaft 13: Journal Shaft 14: Summing shaft 15: Meteor Reversal Gear 16: 1st mechanical branch 17: Transmission housing 18: Planetary gear train device 19: Coupling shaft 20: Meteor Carrier 21: Piston 22: 2nd Branch: Hydraulic 23: Hydrostatic shaft 24: Output shaft 25: Power Flow 30: Power splitter transmission 31: Additional gear stage K1: 1st clutch K2: 2nd clutch K3: 3rd clutch KS: Clutch for additional gear KL: Another clutch for additional gears K2V / K2R: Double Claw Clutch HA: Rear axle VA: Front axle HL: Hydrostatic power component η: Efficiency V: Forward driving range R: Reverse driving range M: Motor PU: Pump K2V: First closed position of the double claw clutch for V K2R: Second closed position of the double claw clutch for R H1: 1st hydraulic unit H2: 2nd hydraulic unit P: Meteor Carrier Z1: Large Sun Gear Z1': Small sun gear Z2: Double planetary gear Z2': Double planetary gear Z3: 1st ring gear Z4: Gear wheel on the outer rim of the Z3 Z5: Gear wheel assigned to H1 Z6, Z7: First gear transmission Z7', Z7", Z6', Z6: 2nd gear transmission Z9, Z10: Gear between 23 and K1 Z11: Gear wheel assigned to the coupling shaft Z12: Gear wheel of the first mechanical branch Z13: Adjacent gear wheel Z11': 1st auxiliary gear wheel Z11'S: Second auxiliary gear wheel Z11L: 3rd auxiliary gear wheel Z20, Z21, Z22: Reverse Planetary Gear Z23: Shift Sleeve / Reverse Ring Gear Z30, Z31, Z32, Z33: Differential lock

Claims

Claim 1 A power branching type transmission (30), comprising: a drive shaft (12); a first mechanical branch (16); a planetary gear train device (18) having a planetary carrier (P) having two or more sun gears (Z1, Z1') including a large sun gear (Z1) and a small sun gear (Z1'), a first ring gear (Z3), and a double planetary gear (Z2, Z2') meshing with said sun gear (Z1, Z1') and the first ring gear (Z3); - at least one of said sun gears is coupled to the drive shaft (12); a continuously adjustable second branch (22) that can be at least partially connected to the first mechanical branch (16) through the planetary gear train device (18) and includes two or more adjustable hydraulic units (H1, H2), wherein the hydraulic units can be energetically coupled to each other and each can be operated as a motor (M) or a pump (PU) in two directions; - Among two or more hydraulic units (H1, H2), the first hydraulic unit (H1) is coupled to the first ring gear (Z3) through a first gear wheel and a second gear wheel located on the outer rim of the first ring gear (Z3)-; and an output shaft (24) capable of being coupled to the drive shaft (12) through a first mechanical branch (16) and a second branch (22);In a power branching type transmission having, the planetary gear train device (18) includes a planetary reverse gear device (15), and the rotational direction of the first mechanical branch (16) can be reversed by the planetary reverse gear device, and the planetary reverse gear device (15) has a shift sleeve (Z23) formed as a reverse ring gear and axially adjustable, and in a first axial position, the shift sleeve (Z23) directly transmits the rotational direction of the planetary carrier (P) to the reverse planetary gears (Z20, Z21, Z22), and the reverse planetary gears are connected to the summing shaft (14) in a forced coupling manner through three gear wheels (Z11, Z12, Z13) including a first gear wheel and an adjacent second gear wheel associated with the coupling shaft (19) of the first mechanical branch (16), and in a second axial position, the shift sleeve (Z23) is a power branching type A power branching type transmission (30) in which rotation of the planetary carrier (P) is directly or indirectly blocked from rotation of the transmission housing (17) of the transmission (30), so that the rotational direction of the planetary carrier (P) is reversed and acts in the reversed rotational direction on the summing shaft (14), and the first mechanical branch and the second branch are joined through the summing shaft.; Claim 2 delete Claim 3 delete Claim 4 In claim 1, the power branching type transmission (30) is formed as a ring gear having a reverse planetary gear (Z20, Z21, Z22) including an odd number of gears, wherein the shift sleeve (Z23) is formed as a reverse planetary gear (Z20, Z21, Z22). Claim 5 In paragraph 4, a power branching type transmission (30) in which the radial inner gear wheel (Z20) of the odd number of gears of the reverse planetary gears (Z20, Z21, Z22) of the shift sleeve (Z23) is fixedly connected to rotate integrally with the first mechanical branch (16) by means of a coupling shaft (19). Claim 6 In paragraph 5, the coupling shaft (19) is formed as a hollow shaft and surrounds the journal shaft (13) connected to the drive shaft (12), power branching transmission (30). Claim 7 In paragraph 1, the first mechanical branch (16) is connected or may be connected to the downstream of the planetary reverse gear device (15) in the direction of the power flow (25), and the second branch (22) is connected or may be connected to the summing shaft (14) connected to the output shaft (24) through the first clutch (K1), power branch type transmission (30). Claim 8 In claim 7, the first mechanical branch (16) is connected to the summing shaft (14) through an odd number of gear wheels (Z11, Z12, Z13) on the output side of the coupling shaft (19), in a power branching type transmission (30). Claim 9 In paragraph 8, a power branching type transmission (30) in which a second clutch (K2) is assigned to the second branch (22). Claim 10 In claim 9, the first clutch (K1) is formed as a claw clutch assigned to the summing shaft (14) for disengageable interaction with the hydrostatic shaft (23) of the second hydraulic unit (H2) among two or more hydraulic units (H1, H2), in a power branching transmission (30). Claim 11 In paragraph 10, the second clutch (K2) is assigned to the hydrostatic shaft (23) of the second hydraulic unit (H2), and the second clutch is formed as a double claw clutch (K2V / K2R) so that the second hydrostatic unit (H2) interacts with the small sun gear (Z1') through the first gear transmission (Z6, Z7) in the first closed position (K2V) and interacts with the small sun gear (Z1') through the second gear transmission (Z7', Z7", Z6', Z6) in the second closed position (K2R), in a power branching transmission (30). Claim 12 In claim 8, an additional gear stage (31) is disposed between a gear wheel (Z11) coupled to a coupling shaft (19) and an adjacent gear wheel (Z13) adjacent to the gear wheel (Z11) coupled to the coupling shaft (19), and the additional gear stage (31) detachably couples a first auxiliary gear wheel (Z11') assigned to the coupling shaft (19) to an adjacent gear wheel (Z13) through two clutches (KS, KL) and a second auxiliary gear wheel (Z11'S) and a third auxiliary gear wheel (Z11L), in a power branching transmission (30). Claim 13 A method for operating a power-dividing transmission (30) according to claim 1, comprising adjusting the shift sleeve (Z23) to a first shaft position that is not fixed so as to rotate integrally with respect to the transmission housing (17) in the forward driving range (V), and a second hydraulic unit (H2) is coupled to the summing shaft (14) through the first clutch (K1), the third gear wheel (Z9), and the fourth gear wheel (Z10), and the first hydraulic unit (H1) is pivoted in a positive angle range in the first pivot direction from a pivot position where the pivot angle is 0° and operates as a pump (PU), and the second hydraulic unit (H2) operates as a motor (M). Claim 14 In paragraph 13, a method of operation of a power branching transmission in which, in the second stage of the forward driving range (V), the first hydraulic unit (H1) is operated as a motor (M) and the second hydraulic unit (H2) is operated as a pump (PU), and the second hydraulic unit (H2) is coupled to a small sun gear (Z1') through the second clutch (K2) and the first gear transmission (Z6, Z7) and pivots from a pivot position of 0° to a negative angle range. Claim 15 A method for operating a power-dividing transmission (30) according to claim 1, comprising adjusting the shift sleeve (Z23) to a second axis position in which the shift sleeve (Z23) is fixed to rotate integrally with respect to the transmission housing (17) in the reverse driving range (R), wherein the first hydraulic unit (H1) is operated as a pump (PU) and the second hydraulic unit (H2) is operated as a motor (M), and the first hydraulic unit (H1) is pivoted in a negative angle range from a pivot position of 0° to a second pivot direction. Claim 16 In claim 15, a method of operation of a power branching transmission in which, in the second stage of the reverse driving range (R), the first hydraulic unit (H1) is operated as a motor (M) and the second hydraulic unit (H2) is operated as a pump (PU), and the second hydraulic unit (H2) is coupled to a small sun gear (Z1') through a second clutch (K2) and a second gear transmission (Z7', Z7", Z6', Z6) and pivots from a pivot position of 0° to a negative angle range. Claim 17 A vehicle equipped with a power branching type transmission (30) according to paragraph 1.

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