Patent Application
20170152941
The present invention relates to a single-motor transmission actuator for a motor vehicle transmission device, which has a plurality of gear steps for forming gears.
A transmission actuator according to the invention is understood in particular to mean a transmission actuator which, operating within a motor vehicle, affects at least one of the following devices: operating, selecting and/or shifting vehicle transmission, clutch and brake.
As is known, the gears of motor vehicle transmissions, such as automated shift transmissions (ASTs), parallel shift transmissions (PSTs) or dual-clutch transmissions (DSTs) or other similar transmissions, may be engaged and disengaged by means of a transmission actuator, which in that case constitutes what is known as an external gear shifter.
For example, it is known from DE 10 2004 038 955 A1 to use exactly one electric motor in a transmission actuator of a motor vehicle to perform both the selecting motions and the shifting motions in the transmission. Such a transmission actuator is therefore also referred to as a single-motor transmission actuator.
Furthermore, it is known from DE 10 2006 054 901 A1 of the applicant to construct this single-motor transmission actuator so that a rotation of an electric motor (as the drive unit for the transmission actuator) in one direction brings about a shifting motion, and a corresponding motion of the electric motor in the other direction brings about a selecting motion of the selector shaft of the transmission. To switch from a shifting motion and a selecting motion, the transmission actuator has a connecting device which couples a spindle nut with appropriate gear racks or gear wheels to bring about a shifting or selecting motion of the selector shaft.
Furthermore, from DE 10 2006 017 158 A1 a gate is known which has a firmly positioned first gate part with a cylindrical surface area and circumferential slots spaced apart axially on it. The gate also includes a second gate part, situated so that it is can rotate or swivel, which is connected axially immovably and non-rotatingly to the selector shaft. The second gate part can swivel into the respective axially spaced slots of the first gate part, depending on its axial position. The gate is thus a guiding device, which limits the adjustability of the transmission actuator, that is, the adjustability of the selector shaft of the transmission actuator, essentially to an adjustability corresponding to a shift track/selection track arrangement. That is, the gate causes the rotatability of the selector shaft to depend on the axial position of said selector shaft, and/or causes the axial movability of the selector shaft to depend on the swiveled or rotary position of the selector shaft. In the case of this gate, on the lands positioned between the circumferential slots chamfers are provided on both sides of each slot, so that it is easier for the second gate part to swivel into the first gate part.
However, with a single-motor transmission actuator, this two-sided chamfer can result in the entire connecting device being tightened, so that the function of the transmission actuator may be impaired.
With regard to the construction of a single-motor transmission actuator for a motor vehicle transmission device, you are referred to the as-yet unpublished DE 10 2013 207 871 of the applicant, which is hereby referenced in its entirety.
It is an object of the present invention to provide a single-motor transmission actuator whose shifting and selecting motions may be controlled precisely by a gate, so that improper operation of the transmission is prevented and tightening of the connecting device of the transmission actuator is avoided.
The invention relates to a transmission actuator for a motor vehicle transmission device, in particular a single-motor transmission actuator, wherein the motor vehicle transmission device has a plurality of gear steps for forming gears. The transmission actuator has a selector shaft, which is supported so that it is rotatable for shifting gears and so that it is axially movable for selecting gears. The transmission actuator has a gate with a fixed-position first gate part and an axially movable and rotatable second gate part, the one gate part having slots and lands alternating in one direction and the other gate part having at least one element that is able to interact with one of the lands at a time and is movable in one of the slots at a time. In a selecting motion the at least one element is moved in a prescribed direction past the lands and slots (i.e., in particular perpendicular to the direction of the slots and lands), and in a shifting motion it is moved into one of the slots, i.e., parallel to the direction of the slots and lands). An insertion chamfer is provided at least on the lands or on the element, so that when there is a collision between element and land during the shifting motion, the second gate part can be moved further in the specified direction of the selecting motion by means of the insertion chamfer and the shifting motion can be continued, whereas otherwise essentially right-angled transitions are provided, so that then in the collision between element and land during the shifting motion the second gate part is not movable contrary to the prescribed direction of the selecting motion, but rather the shifting motion is stopped.
The transmission actuator with gate proposed here is suitable in particular as a single-motor transmission actuator, as it is known from the as-yet unpublished DE 10 2013 207 871. This document is hereby referenced in its entirety. The single-engine transmission actuator described there is to be augmented by the gate described here.
Furthermore, however, the present invention is also employable for other transmission actuators. In the cited DE 10 2013 207 871 the single motor produces two rotation directions, which are converted by means of the connecting device to a rotary motion (shifting motion) and a linear travel motion (selecting motion) of the selector shaft. To guide this selecting motion (linear travel motion) and shifting motion (rotary motion) of the selector shaft a gate is provided, which ensures that the selector finger, which is positioned on the selector shaft and actuates the transmission of the motor vehicle, is located in the right position relative to the transmission.
In this single-motor actuator, a so-called free-wheel mechanism is provided in the connecting device, which enables a rotation in one direction, and when there is a rotation in the other direction it blocks this rotary motion (blocking direction).
To prevent a motion of the selector shaft contrary to this blocking direction, there is now provision for an insertion chamfer to be positioned so that when there is a collision between element and land during the shifting motion the second gate part can be moved further in the specified direction of the selecting motion by means of the insertion chamfer and the shifting motion can be continued, whereas otherwise in a collision between element and land during the shifting motion the second gate part is not at all movable contrary to the prescribed direction of the selecting motion, but rather the shifting motion is stopped. Specifically in this case, i.e., when a free-wheel mechanism is provided in the connecting device, a tightening of the connecting device will come about and the function of the transmission actuator will also be impaired for a long time.
In particular, the element has a first wall pointing in a prescribed direction and an end face pointing toward the slot, there being an insertion chamfer between the end face and the first wall. Furthermore, the element has a second wall pointing opposite the prescribed direction, there being between the end face and the second wall an essential right-angled transition (90-degree angle).
The insertion chamfer is thus at an angle of less than 90 degrees relative to the prescribed direction, in particular between 50 and 70 degrees. At the same time, the insertion chamfer has a length in the direction of the shifting motion such that the second gate part is movable further in the prescribed direction by a distance beyond the length of the insertion chamfer.
According to a preferred design, the second gate part has the slots and lands.
In particular, the second gate part is positioned immovably on the selector shaft and is movable with the selector shaft relative to the fixed first gate part. This means in particular that the second gate part is firmly connected to the selector shaft and can only be moved together with the latter, while the first gate part is fixed on the housing, so that the selector shaft is moved relative to this first gate part.
According to another especially preferred design, the second gate part has the slots and lands and is positioned coaxially to the selector shaft and extends around the selector shaft, while the slots and lands extend in a circumferential direction and the second gate part has in addition at least one track in which the at least one element of the first gate part is movable during the selecting motion.
In particular, the second gate part has slots and lands on both sides of the at least one track, and in the case of a selecting motion in a first direction, the shifting motion occurs only in a first circumferential direction, and in the case of a selecting motion in a second direction, contrary to the first direction it occurs only in a second circumferential direction, the at least one element accordingly having two end faces. One end face interacts with the slots and lands on one side of the track.
In particular, the (first, second) direction is referred to as a fixed direction in which the selecting motion occurs. Starting from this fixed direction of the selecting motion, rotation is possible only in one circumferential direction (for example: selecting motion upward, shifting motion to the left; selecting motion downward, shifting motion to the right).
In particular, the second gate part is connected non-rotatingly through first profile toothing on an internal circumferential surface to second profile toothing on an external circumferential surface of the selector shaft, there being a coding tooth present on each of the sets of profile toothing that allows only one installation position of the second gate part and the selector shaft relative to one another. In particular, one tooth of the profile toothing (and a corresponding gap between the teeth of the other profile toothing to receive that tooth) is not completely formed, so that the first profile toothing on the internal circumferential surface cannot be slid over the profile toothing on the external circumferential surface if the coding teeth are not opposite one another.
In particular, there is a marking positioned on the first gate part, so that the installation position is recognizable.
In particular, the first gate part is ring-shaped and positioned coaxially to the selector shaft, and extends around the selector shaft and around the second gate part.
According to another advantageous refinement, the first gate part has two elements positioned opposite one another and the second gate part has two tracks positioned opposite one another. Positioned opposite means here that the gate part is symmetrical when rotated by 180°. The tracks and elements are thus positioned on opposite sides of the common axis of the selector shaft. Such an arrangement of two elements at a time, which interact simultaneously with slots, lands or tracks, increases the sturdiness and thus the wear-resistance of the gate and therefore of the transmission actuator.
According to another especially advantageous design, the transmission actuator includes a spindle with a spindle nut, where the spindle nut forms a toothed rack and is operatively connected to a shaft gear through one of two gear wheels at a time, the shaft gear being firmly connected to the selector shaft. The spindle nut itself forms the second gate part in this case, with the slots and lands running parallel to a spindle axis. The element of the first gate part is formed by at least one pin, which is able to interact with the slots and lands of the spindle nut.
For this embodiment, we refer in particular to the construction of the transmission actuator according to DE 10 2013 207 871. In particular, the second gate part is formed by the spindle nut provided there. The pin is fixed with respect to the housing, and represents the first gate part. The pin, together with the second gate part, forms the arresting device on the spindle nut or the latching of the spindle nut in the first axial position zone.
In particular, the first gate part has two pins in this case, which are positioned parallel to one another and on opposite sides of the spindle axis.
The arrangement of two pins or two elements opposite one another (i.e., on opposite sides of a spindle axis or of the axis of the selector shaft) serves to achieve a more stable arrangement of the first gate part and the second gate part. Furthermore, the first gate part and the second gate part thus have no preferred direction up/down or 0°/180°, so that the assembly can be carried out more safely.
The present invention is also directed at a method for selecting and shifting gears using a transmission actuator, in particular a transmission actuator according to the invention, where a control system is provided and the process comprises the following steps:
The function of the gate is to prevent a selecting motion outside of the track or outside of the selection band. Furthermore, a shifting motion in a position between tracks is prevented; that is, the possibility of two gears being engaged at the same time is prevented. Thus, the gate ensures that exactly one target shift track or shift slot is found. The insertion chamfer serves to increase the production tolerances of the elements involved in the shifting motion, for example the selector finger, so that even larger mis-positionings of these elements relative to each other can be compensated for, thus reducing the number of unsuccessful attempts at shifting procedures.
Furthermore, the gate serves as torque support when returning from the slot into the selection band (for example, the track). Without the gate, there is no definition on this return path of whether the transmission actuator is to perform a motion in the selecting or shifting direction. The gate ensures that a selecting motion is only possible when the element is situated in the track and is movable along the track. Only then is the gearshift lever in the motor vehicle transmission device movable in such a way that the gearshift rails are not actuated to engage a gear.
The features listed individually in the patent claims can be combined with each other in any technologically reasonable way, and can be supplemented by explanatory facts from the description and details from the figures, in which case additional variant embodiments of the invention will be shown. In particular, the statements about the transmission actuator can be transferred to the method and vice versa.
The invention as well as the technical environment will be explained in greater detail below on the basis of the figures. The figures show especially preferred exemplary embodiments, although the invention is not limited to these. In particular, it must be pointed out that the figures, and especially the depicted size proportions, are only schematic. Like reference labels designate like objects. The figures show the following:
A spindle nut 31 is situated on the (threaded) spindle 30. The spindle nut 31 meshes by means of toothing 56 (see
If the spindle nut 31 is moved along the spindle 30, the engagement with a third gear wheel 49 is enlarged; that is, areas of overlap are gained. It would also be possible for a meshing to come about only with this motion. As long as the spindle nut 31 is in a first axial position range 50 of the threaded spindle 30 and is meshed with a detent mechanism 48, the spindle nut 31 cannot move axially against the holding force of the detent mechanism 48. A rotation of the selector shaft 3, that is, a shifting procedure, does not become possible until the spindle nut 31 has been moved far enough out of this first axial position range 50 and along the spindle 30 into a different axial range, until the holding force between the spindle nut 31 and the detent mechanism 48 has been overcome. The spindle nut 31 is now connected to the free-wheel mechanism 51 through the third gear wheel 49. The free-wheel mechanism 51 allows a rotary motion only in a second direction of rotation 45, so that the spindle nut 31 is able to perform a rotary motion exclusively in a first direction of rotation 44. Also positioned on the axis of rotation of the free-wheel mechanism 51 is a selector wheel 52, by means of which the rotation of the spindle nut 31 and of the motor spindle 43 is transmitted to a selector pot 53. The selector pot 53 may also be driven accordingly exclusively in one direction of rotation, and with the help of a trajectory 54 on its circumference transforms the rotary motion into an up-and-down motion of guide pins 55, which engage with the trajectory 54 and are connected to the selector shaft 3. The up-and-down motion of the guide pins 55 thereby corresponds to a selecting motion 11 of the selector shaft 3. This selecting motion 11 is carried out as long as the motor 41 is moving in the first direction of rotation 44. If the motor 41 is turning, its direction of rotation stops the selecting motion 11 because of the free-wheel mechanism 51. But the spindle 30 is now turning and the stationary spindle nut 31 moves back along the spindle 30 into the first axial position range 50, in which further axial motion is stopped again by the detent mechanism 48. With this first axial movement 60 of the spindle nut 31, the spindle nut 31 is again meshed by means of the toothing 56 with one of two gear wheels 33, 34 at a time, which are operatively connected to the selector shaft 3. The shifting motion 12 is thus performed by means of the axial movement of the spindle nut 31.
The specification description of DE 102013207871 is referenced in its entirety.
The gear wheel pairings, which transmit the motion of the motor 41 to the spindle 30, to the free-wheel mechanism 51, to the selector pot 53 and to the shaft gear 35 and thereby bring about the selecting motion 11 and the shifting motion 12 of the selector shaft 3, are referred to as the connecting device 18.
In the depiction shown here, the selector finger 62 is positioned directly before a gearshift rail 57, so that when the selector shaft 3 makes a shifting motion 12 a gear may be engaged. This position of the selector finger 62 before the gearshift rail 57 is set by the gate 4. To this end, the gate 4 has a second gate part 6 with lands 9 and slots 8, the second gate part 6 being positioned around the selector shaft 3 and coaxial to the selector shaft 3. Here, a first gate part 5 with an element 10 extends around the second gate part 6 in such a way that the element 10 can reach in from outside into the slot 8 between lands 9. This makes it possible when the selector shaft 3 makes a shifting motion 12 for the second gate part 6, which is firmly connected to the selector shaft 3, to be turned in a circumferential direction 19, 20 relative to the first gate part 5, so that the element 10 dips into the slot 8 in the course of a shifting motion 12.
It can be seen here that in the case of the second gate part 6 shown, another track 21 is positioned opposite. This would enable the second gate part 6 to be installed (for example if there are two coding teeth 27) also rotated by 180° and also possibly tilted by 180°.
The gate 4 now has the following functions, which are depicted schematically in
Furthermore, the gate 4 makes it possible for greater production tolerances of the elements involved in the shifting motion, such as the selector finger, to be permissible; even larger mis-positionings of these elements relative to each other can be compensated for, thus reducing the number of unsuccessful attempts at shifting procedures, while at the same time a tightening of the connecting device 18 is avoided. That is, particularly with the single-motor transmission actuator 1, it is important to avoid a movement of the selector shaft 3 being provoked or forced which acts in the blocked direction of rotation of the free-wheel mechanism 51.
The slots 9 and lands 8 are now moved in the prescribed direction 58 past the element 10 under the selecting motion 11, while under a shifting motion 12 the second gate part 6 is swiveled in a circumferential direction 19, 20 relative to the element 10 in such a way that the element 10 can be moved into one of the slots 9. If a shifting motion 12 occurs in the depicted position of the element 10, then by means of the insertion chamfer 13 the right element 10 can push the second gate part 6 further in the prescribed direction 58 of the selecting motion 11, so that the slot 8 is reached and the element 10 can be pushed into the slot 8. Thereby, the selector finger 62 is also positioned correctly, so that mis-positionings of the selector finger 62 and/or of the slot 8 are also compensated for and thus the available window for shifting the gear has been enlarged. But if a shifting motion 12 is carried out in circumferential direction 20, the left element 10 interacts with the slots 9 and lands 8 of the other side 26 of the track 21.
The insertion chamfer 13 is thus at an angle 63 of less than 90 degrees relative to the prescribed direction 58, in particular between 50 and 70 degrees. At the same time, the insertion chamfer 13 has a length 65 in the direction of the shifting motion 12 (here circumferential direction 20) such that the second gate part 6 is movable further in the prescribed direction 58 by a distance 64 beyond the length 65 of the insertion chamfer 13. These statements are transferable correspondingly to insertion chamfers 13 on the second gate part 6 (or to the gate for 4 according to the second variant embodiment in
Here, the spindle nut 31 forms the second gate part 6. Slots 9 and webs 8 run parallel to a spindle axis 36, and the element 10 of the first gate part 5 is formed by at least one pin 37 (here by two pins which are positioned parallel to one another and on opposite sides of the spindle axis 36).
Independent of the configuration described above, it is of course possible to reverse the operating principle of the described transmission actuators. For a person skilled in the art, it is easily possible here to attach a gate rail in a fixed location which corresponds to the gate 4 described above, but is constructed essentially complementarily to that gate 4, i.e., among other things hollow inside. This gate rail would then be fixed with respect to a housing and would provide slots 8 for elements 10 positioned non-rotatingly on the selector shaft 3. The first gate part would then be constructed correspondingly complementarily to the first gate part 6 and would be connected to the selector shaft 3.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2014 205 659.4 | Mar 2014 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/DE2015/200100 | 2/24/2015 | WO | 00 |
