CN112105832A

CN112105832A - Parking lock system for vehicle transmission system

Info

Publication number: CN112105832A
Application number: CN201980027955.7A
Authority: CN
Inventors: R·韦尔波特恩; P·P·L·凡德普特
Original assignee: Punch Powertrain NV
Current assignee: Nanjing Bangqi Automatic Transmission Co ltd
Priority date: 2018-04-26
Filing date: 2019-04-25
Publication date: 2020-12-18
Anticipated expiration: 2039-04-25
Also published as: CN112105832B; BE1026240A1; BE1026240B1; WO2019207038A1

Abstract

A park lock system (10) for a vehicle driveline (12) includes a driveline gear (14) and a gear lock (22) having a plurality of spaced apart gear lock teeth (24) and alignment teeth (38). The locking gear is axially movable from a locking position to a releasing position. The gear locking part (22) can also be arranged tangentially movably and biased in the initial position by a biasing means. The tips of the alignment teeth are offset tangentially relative to the tips of the gear locking teeth (24) and project beyond the gear locking teeth towards the gear (14) so that correct and shock-free engagement between the gear locking teeth (24) and the gear teeth (16) is always ensured.

Description

Parking lock system for vehicle transmission system

Technical Field

The present invention relates to a park lock system for a vehicle driveline.

Background

Parking lock systems are used to immobilize a vehicle when the vehicle is parked and not in use. These systems lock the wheels of the vehicle from rotating and keep the vehicle stopped. This is true for both manual and automatic transmissions. In vehicles with manual transmissions, the engine may be used to immobilize the vehicle while parked by placing the transmission into one of the drive gears. Even so, however, it is desirable for the auxiliary device to immobilize the vehicle. The most common is the handbrake.

With an automatic transmission, it is not possible to use the engine to immobilize the vehicle. In vehicles with automatic transmissions, there is no direct fixed mechanical coupling between the engine and the wheels due to the commonly used configuration of fluid couplings. Also, with a dual clutch transmission, there is no direct mechanical coupling between the engine and the wheels. In both cases, the park lock system is the means by which the vehicle is immobilized.

Parking lock systems are typically integrated into transmissions and/or other vehicle driveline components and are used to immobilize and fix rotatable portions of a vehicle driveline. To this end, parking lock systems are known that are coupled to a portion of the transmission itself (e.g. a transmission gear), or to another gear (which is coupled to the transmission for common rotation).

An example of such a known system is US 3,990,541 (US' 541). US' 541 discloses a park lock mechanism for a transmission in which a pivotable latch can engage a gear in the vehicle transmission when the vehicle is parked, thus securing the gear in a non-rotatable position. The pivotable latch includes two lugs spaced apart a distance different from one or more of the pitches of the teeth of the gears with which the latch engages to lock against rotation. In this way, the mechanism of the invention can ensure that the latch will always and immediately be set in the latched and secured position when required by means of one of its two lugs, and that it is not necessary to rotate the gear to a particular position to effect the latching described.

Another example of such a known system is US2016/0097443 a1 (US' 443). In US' 443, the differential housing is rotatably mounted in a transmission component housing. The differential case is provided with a plurality of gear teeth that extend circumferentially around the differential case and are engaged by the drive pinion to rotate the differential case within the driveline component housing. For the parking lock function, the differential case is provided with a plurality of first face teeth. The driveline component housing is provided with a first plurality of radial teeth. The annular locking element includes a plurality of second radial teeth that mesh with the first radial teeth. The annular locking element further comprises a second face tooth which engages with the first face tooth in a first axial position of the annular locking element, which first axial position forms a locking position. Thus, the differential carrier is rotationally locked relative to the transmission component housing. The annular locking element is axially slidably mounted and slidable to a second axial position in which the second face teeth of the annular element are disengaged from the first face teeth such that the differential case is rotatable within the driveline component housing.

The solutions of the known systems present their own problems. In US' 541 only one tooth (lug) is used for engagement, a considerable engagement force is required due to the small contact surface. A problem with US2016/0097443 is that when the top of a first face tooth is opposed to the top of a second face tooth, the ring element cannot slide into the first axial position and therefore the locking position cannot be achieved. The ring element can only be brought into the first axial position after some rotation of the differential carrier, i.e. after a certain movement of the vehicle, in order to achieve the locking function, which in many cases may lead to shock loads and undesired movements.

Disclosure of Invention

It is an object of the present invention to provide a park lock system for a vehicle driveline having an improved lock mechanism.

To this end, the invention provides a parking lock system for a vehicle driveline according to claim 1.

More specifically, the parking lock system according to the present invention includes: a gear coupled to a rotatable member of a transmission system, the gear including a plurality of circumferentially spaced gear teeth aligned along a gear tooth circle having a gear circle radius; a gear lock comprising a plurality of spaced apart gear lock teeth, wherein tips of the gear lock teeth are spaced apart at a pitch of the gear lock teeth. The gear locking portion is movably arranged along the first axis such that it can be moved towards and away from the gear. The gear locking portion has a locking position in which the gear locking portion teeth engage with the gear teeth, thus preventing rotation of the gear, and a releasing position in which the gear locking portion is disengaged from the gear, thus disengaging the gear locking portion teeth from the gear teeth, thus making the gear rotatable. The gear lock is movably arranged along a portion of a circular line having a radius substantially equal to the gear circle radius. The gear lock includes alignment teeth having tips (tooth tips) that are tangentially offset relative to the tips of the gear lock. The alignment teeth have a projecting position in which the tip of the alignment teeth projects toward the gear beyond the tip of the gear lock teeth (tooth tip).

The gear locking portion may move in two directions along a portion of the circular line.

The gear lock may comprise an annular body and the gear lock teeth may be spaced along an entire circle.

The parking lock system may include a biasing device configured to bias the gear lock portion at an initial position and allow the gear lock portion to move along a portion of the circular line.

The biasing means may comprise at least one biasing spring urging the gear lock into the initial position, wherein the at least one biasing spring allows the gear lock to move in a direction along a portion of the circular line.

The alignment teeth are movable relative to the gear locking teeth in a direction substantially parallel to the first axis.

The alignment teeth are movable between an alignment position in which the tips of the alignment teeth are aligned with the tips of the gear lock teeth in the addendum plane of the gear lock teeth and a protruding position.

The park lock system may also include an alignment tooth spring that urges the alignment tooth into the projecting position.

The aligned teeth spring may be disposed in the gear lock.

The alignment teeth may advantageously have a different profile than the profile of the gear locking teeth.

Further, the alignment teeth may have an asymmetric profile.

The park lock system may also include an actuator assembly that, when actuated, urges the gear lock into the locked position.

The actuator assembly may include a pressure block, a self-locking trapezoidal spindle, and an actuator, an outer surface of the pressure block pushing directly on an outer surface of the gear-locking portion, the actuator connected to the self-locking trapezoidal spindle and configured to rotate the self-locking trapezoidal spindle. The self-locking trapezoidal mandrel may be rotatably coupled to a threaded bore in the press block. When the self-locking trapezoidal spindle rotates in a first direction, it pushes the pressing piece toward and onto the gear-locking portion, so that the pressing piece pushes the gear-locking portion from the release position to the locking position. When the trapezoidal spindle rotates in a direction opposite the first direction, it pulls the press piece away from the gear lock.

Alternatively or additionally, the actuator assembly may comprise at least one tension spring which pulls the gear lock in the direction of the release position.

The at least one tension spring may further constitute a biasing means configured to bias the gear lock portion in the initial position and to allow the gear lock portion to move along a portion of the circular line.

The gear lock teeth may be rounded and/or chamfered.

The gear lock may be mounted in a gear lock chamber defined by the gear lock housing. Preferably, the gear lock housing may be integrated with a clutch or transmission housing of a vehicle.

The movement of the gear lock along a portion of the circular line may be limited by a wall of the gear lock housing.

The invention also provides a vehicle comprising a parking lock system according to the invention.

When the gear lock is moved toward the gear, the gear lock teeth and gear teeth will mesh. One advantage of the present invention is that a plurality of teeth are used for engagement, and that the rotational force or torque of each tooth is less than if only one tooth or lug were used. The gear locking portion can reach its locking position only when the tips of the gear locking portion teeth are precisely aligned midway between the tips of the gear teeth, without relative displacement in a tangential direction of the gear tooth circle. When this alignment does not occur, the gear lock teeth and gear teeth will mesh before the locking gear reaches its locked position and thereby force the gear lock into a tangential position where the tips of the gear lock are precisely aligned midway between the tips of the gear teeth. By means of the tangentially movable gear lock, the gear does not have to be rotated during meshing. This has the advantage that the vehicle driveline does not rotate. Because the gear can be parked at any given arbitrary position, the gear lock teeth and the ends of the gear teeth are aligned directly opposite each other. In that case, moving the gear lock from the release position towards the gear wheel along the first axis would correspond to pushing the tips of the two sets of teeth onto each other. This condition may prevent effective park lock engagement. Alternatively, a set of teeth may yield, causing one or both of the gear and/or gear lock to move, and thus causing the gear lock to move abruptly and quickly toward its locked position, with an accompanying shock load being generated. The presence of the alignment teeth in combination with the directionally movable gear locking portion can address such unwanted movement and ensure effective park lock engagement under all conditions.

The invention will be further elucidated with reference to the drawings of an exemplary embodiment. The embodiments may be combined with each other or may be applied separately from each other.

Drawings

FIG. 1 illustrates a perspective side view of a transmission of a vehicle driveline having an embodiment of a park lock system mounted thereon;

FIG. 2 illustrates a top view of the transmission of FIG. 1;

FIG. 3 is a side perspective view of the park lock system of FIG. 2 in the direction of arrows A and A' shown in FIG. 2;

FIG. 4 shows a cross-sectional view of the park lock system taken along line A-A';

FIG. 5 shows an enlarged detail of the cross-sectional view of FIG. 4; and

FIG. 6 shows a bottom view of the park lock system according to the embodiment of FIG. 3 with the gears removed;

fig. 7 shows a perspective top/side view of an example of a gear lock and a pressure piece according to the invention mounted on a gear;

FIG. 8 shows an exploded top/side view of the gear lock, press block and gear of FIG. 7;

fig. 9 shows an exploded bottom/side view of the gear lock, press block and gear of fig. 7.

Detailed Description

In the present application, similar or corresponding features are denoted by similar or corresponding reference numerals. The description of the various embodiments is not limited to the examples shown in the drawings, and the reference numerals used in the detailed description and claims are not intended to limit the description of the embodiments but are included to clarify the embodiments by referring to the examples shown in the drawings.

In general, the present invention is directed to a park lock system 10 for a vehicle driveline 12, the park lock system 10 comprising: a gear 14 connected to a rotatable member of the transmission 12, the gear including a plurality of circumferentially spaced gear teeth 16 aligned along a gear tooth circle (teeth circle)18 having a gear circle radius 20; a gear lock 22 comprising a plurality of spaced apart gear lock teeth 24, wherein the tips of the gear lock teeth 24 are spaced apart at the pitch of the gear lock. The gear lock 22 is movably arranged along a first axis 26 such that it can be moved towards and away from the gear 14. The gear locking portion 22 has a locking position in which the gear locking portion teeth 24 are engaged with the gear teeth 16, thus preventing rotation of the gear 14, and the gear locking portion 22 has a releasing position in which the gear locking portion 22 is disengaged from the gear 14, thus disengaging the gear locking portion teeth 24 from the gear teeth 16, thus allowing the gear 14 to rotate. The gear lock 22 is movably arranged along a portion of a circular line 30 having a radius 32 substantially equal to the gear circle radius 20. The gear lock 22 also includes alignment teeth 38 whose tips are tangentially offset relative to the tooth tips of the gear lock. The alignment teeth 38 have a projecting position in which the tips of the alignment teeth 38 project beyond the tips of the gear lock teeth 24 toward the gear 14. It is apparent that the above also covers embodiments in which the gear locking portion 22 includes more than one alignment tooth 38.

When the driver parks the vehicle, it is generally preferred that the vehicle does not move until the driver returns. If the vehicle is on a slope, for example, gravity will tend to move the vehicle, causing the wheels and therefore the driveline 12 to rotate as well. The objective of the parking lock system 10 is to prevent such unwanted movement. The parking lock system 10 is operated by means of engagement of the gear lock 22 with the gear 14, or more specifically, by means of engagement of the gear lock teeth 24 with the gear teeth 16. The gear 14 is part of the vehicle driveline 12 or may be connected to the driveline. The powertrain component to which parking lock system 10 is directed may be, for example, a differential assembly or axle assembly of a vehicle. In other words, the gear 14 may be part of or may be connected to, for example, a differential assembly or axle assembly of a vehicle. However, other components of the vehicle driveline 12 may also be used.

One advantage of the present invention is that multiple teeth are used to engage, so that the force or torque of each tooth is less than if only one tooth or lug were used. Of course, the engagement of the

teeth

16, 24 should preferably only take place when the vehicle is completely parked. Only then does the gear 14 not rotate. Engaging the gear lock teeth 24 with the gear teeth 16 of the still rotating gear 14 risks damaging the park lock system 10 or even damaging the vehicle driveline 12.

When the gear lock 22 is moved toward the gear 14, the gear lock teeth 24 and gear teeth 16 will mesh. The gear lock 22 can reach its locked position without relative displacement in a tangential direction to the gear tooth circle 18 only when the tips of the gear lock teeth 24 are precisely aligned midway between the tips of the gear teeth 16. When this alignment does not occur (which will be frequent), the gear lock teeth 24 and gear teeth 16 mesh before the gear lock 22 reaches its locked position, and thereby force the gear lock 22 to a tangential position with the tips of the gear lock 22 precisely aligned midway between the tips of the gear teeth 16. By means of the tangentially movable gear lock 22, the gear wheel 14 does not have to be rotated. If the gear lock 22 cannot move tangentially, the engagement of the gear lock teeth 24 with the gear teeth 16 will cause the gear 14 to rotate. This rotation is undesirable because it would imply rotation of the vehicle driveline 12 and movement of the vehicle.

Since the gear 14 can be parked at any given arbitrary position, this is one opportunity for the ends of the gear locking teeth 24 and gear teeth 16 to be directly aligned relative to each other. In that case, moving the gear lock 22 along the first axis 26 from the released position towards the gear 16 would amount to pushing the tips of the two sets of

teeth

16, 24 onto each other, destabilizing the engagement. This can prevent the gear locking portion 22 from reaching its locking position, so that the parking lock cannot be achieved. Alternatively, one set of

teeth

16, 24 may yield, causing one or both of the gear 16 and/or the gear lock 22 to move, and thus causing the gear lock 22 to move abruptly and quickly toward its locked position, with an accompanying shock load being generated. This would be an uncontrolled and undesirable movement that could potentially cause damage to the park lock system 10 and the vehicle driveline 12. The presence of the alignment teeth 38 counteracts this unwanted movement. The alignment teeth 38 project beyond the distal end of the gear lock teeth 24 toward the gear teeth 16. The protrusion may be, for example, about 1 to 5mm, preferably about 2.25 mm.

The alignment teeth 38 work as follows. There are three possibilities regarding the alignment of the gear locking teeth 24 relative to the gear teeth 16.

A first possible alignment of the gear locking teeth 24 relative to the gear teeth 16 is that the tips of the gear locking teeth 24 are aligned with the middle of the space between the gear teeth 16. In this alignment, the sets of

teeth

16, 24 will mesh and the alignment teeth 24 will not be used, nor will the gear lock 22 need to be moved along portions of the circular line 30.

A second possible alignment of the gear locking teeth 24 relative to the gear teeth 16 is that the tips of the gear locking teeth 24 are neither aligned with the middle of the space between the gear teeth 16 nor in direct opposing alignment with the tips of the gear teeth 16. In this alignment, the tips of the gear lock teeth 24 will engage the sides of the gear teeth 16, wherein this interaction will push the gear lock 22 in a tangential direction along a portion of the circular line 30.

A third possible alignment of the gear locking teeth 24 relative to the gear teeth 16 is that the tips of the gear locking teeth 24 are aligned directly opposite the tips of the gear teeth 16. In this alignment, the tip of the alignment tooth 38 will not be directly opposite the tip of one of the gear teeth 16, as the tip of the alignment tooth 38 is tangentially offset relative to the tip of the gear locking tooth 24. During meshing of the gear lock 22 and the gear 14, the projecting alignment tooth 38 will contact one of the gear teeth 16, and subsequently the remaining gear lock teeth 24 will contact the gear teeth 16. The flank of the tooth of gear tooth 16 will push the aligned tooth 38 in a tangential direction along a portion of circular line 30. In so doing, it will also push the gear locking portion 22 in the tangential direction along a portion of the circular line 30. Thus, the interaction between the protruding alignment teeth 38 and the gear teeth 24 will move the gear lock 22 such that the ends of the sets of

teeth

16, 24 will no longer be directly aligned relative to each other. Subsequently, the gear locking teeth 24 will mesh with the gear teeth 16. The gear lock teeth 24 will mesh with the side portions of the gear teeth 16, wherein the interaction will push the gear lock 22 further in the tangential direction. The tangential movement of the gear lock 22 along a portion of the circular line 30 may be guided, for example, by the configuration of the gear lock chamber 28 in which the gear lock 22 may be mounted. The tangentially movable gear lock 22 and the alignment teeth 38 work together to controllably engage the gear lock 22 with the gear 14. The alignment teeth 38 will bias the gear lock 22 in a position to facilitate engagement before the remaining gear lock teeth 24 engage the gear teeth 16.

The above invention has several advantages. As previously mentioned, one advantage is that multiple teeth are used to engage such that the rotational force or torque of each tooth is less as opposed to using only one tooth or lug. Another advantage is that the use of the alignment teeth allows for controlled engagement of the gear lock 22 with the gear 14 regardless of the position of the gear 14 relative to the gear lock 22.

In an embodiment of the present invention, the gear locking portion 22 is movable in two directions along a portion of the circular line 30.

The movement of the gear lock 22 is preferably in a direction that requires a minimum amount of travel to achieve the desired alignment of the gear lock teeth 24 and the gear teeth 16. When the gear locking teeth 24 engage the gear teeth 16, the gear locking teeth 24 will engage the side portions of the gear teeth 16. This meshing may be on one or the other side of the gear teeth 16 due to any alignment of the gear 14 relative to the gear locking portion 22. This means that the gear 14 can push the gear lock 22 in one direction when the gear lock teeth 24 are engaged on one side face of the gear teeth 16, or the gear 14 can push the gear lock 22 in the other direction when the gear lock teeth 24 are engaged on the other side face of the gear teeth 16.

In one embodiment of the present invention, the gear locking portion 22 comprises an annular body and the gear locking portion teeth 24 are spaced apart along an entire circle.

The gear locking portion 22 may include a partial circular portion or an entire circular portion. The movement of the gear locking portion 22 along a portion of the circular line 30 is equivalent to rotating the gear locking portion 22 along a portion of the circular line 30. The rotation is about an axis, which preferably coincides with the first axis 26. An example of the gear locking portion 22 including a partially circular portion is shown in the example of fig. 1 to 5. An example of the gear locking portion 22 including the entire circular portion is shown in the examples of fig. 7 to 9.

In one embodiment of the present invention, the parking lock system 10 further includes a biasing device 34, the biasing device 34 being configured to bias the gear lock 22 in the initial position and to allow the gear lock 22 to move along a portion of the circular line 30.

These biasing means 34 urge the gear locking portion 22 in the initial position. However, when the engagement of the gear locking teeth 24 and the gear teeth 16 causes the gear locking portion 22 to move, the biasing device 34 will allow the directionally movable gear locking portion 22 to move in a direction along a portion of the circular line 30. This movement may be in both directions along a portion of the circular line 30, preferably in a direction from the initial position that requires a minimum amount of travel to achieve the desired alignment of the gear locking teeth 24 and gear teeth 16.

In one embodiment of the present invention, the biasing means comprises at least one biasing spring 34 urging the gear lock 22 into the initial position, wherein the at least one biasing spring 34 allows the gear lock 22 to move in a direction along a portion of the circular line 30.

When the biasing means includes at least one biasing spring 34, the at least one biasing spring 34 will center the gear lock 22 in the initial position when the sets of

teeth

16, 24 are not engaged. The spring constant of at least one biasing spring 34 must be sufficiently small such that the spring force due to the offset or bias of gear lock 22 relative to the initial or rest position is less than the static rotational friction of gear 14 and the subsequently coupled drive train 12. Only then does the gear 14 push the gear locking portion 22 sideways during engagement. The biasing spring 34 may be, for example, a leaf spring or a coil spring. In fig. 4, a plate spring is shown in combination with the partial gear locking portion 22, and in fig. 8, a coil spring is shown in combination with the full-circle gear locking portion 22. These combinations are not restrictive, however, and a plate spring having a full-circle gear locking portion 22 may also be used and a coil spring having a partial gear locking portion 22 may also be used.

In one embodiment of the present invention, the alignment teeth 38 are movable relative to the gear locking teeth 24 in a direction substantially parallel to the first axis 26. The alignment teeth 38 are movable between an aligned position in which the tips of the alignment teeth 38 are aligned with the tips of the gear lock teeth 22 in the addendum plane 40 of the gear lock teeth 24 and a protruding position.

Because the alignment teeth 38 protrude beyond the other gear locking teeth 24, they may be configured to be larger than the other gear locking teeth 24. This extra dimension must be taken into account in order to enable good meshing between the gear locking teeth 24 and the gear teeth 16. This may be accomplished, for example, by making the height of the gear locking teeth 24 smaller than the height of the gap between the gear teeth 16, so that a larger alignment tooth 38 will also fit in the gap between two gear teeth 16. Another solution is to have the alignment teeth 38 movable relative to the gear locking teeth 24 in a direction substantially parallel to the first axis 26. In this way, the tips of the alignment teeth 38 may be aligned with the tips on the gear locking teeth 22 in the addendum plane 40 during meshing of the two sets of

teeth

16, 24, and thus, the alignment teeth 38 do not have any additional height to consider.

In another embodiment of the present invention, the parking lock system 10 may further include an alignment tooth spring 42, the alignment tooth spring 42 urging the alignment teeth 38 into the protruding position. The aligning teeth spring 42 may be provided in the gear locking portion 22.

When the gear lock 22 is in the released position, the alignment teeth springs 42 urge the alignment teeth 38 into the protruding position. During engagement of the gear lock 22 with the gear 14, the gear 14 will urge the projecting alignment teeth 38 into the aligned position against the urging action of the alignment teeth spring 42. The spring constant of the aligning tooth spring 42 should be carefully selected. The spring constant should be high enough so that the gear teeth 16 can push the alignment teeth 38 in a tangential direction along a portion of the line 30 during engagement of the gear lock 22 with the gear 14, and thus push the entire gear lock 22. On the other hand, the spring constant should be low enough so that during engagement of the gear lock 22 with the gear 16, the alignment teeth 38 will be pushed inward and not exert unnecessary force on the gear 16 causing undesired rotation of the gear 16. When using at least one biasing spring 34 as the biasing means, the spring constant of the alignment tooth spring 42 and the spring constant of the at least one biasing spring 34 will have to be balanced with the static rotational friction of the locking gear 22.

In one embodiment of the invention, the profile of the alignment teeth 38 is different from the profile of the remaining gear locking teeth 24. This may be, for example, an asymmetric profile.

In order to offset the tips of the alignment teeth 38 in a tangential direction relative to the tips of the gear locking teeth, the alignment teeth 38 may have exactly the same configuration as the gear locking teeth 24, but simply be tangentially offset. Another possibility for the alignment teeth 38 is to have the profile of the alignment teeth different from the profile of the gear lock teeth 24 in order to offset the tips of the alignment teeth 38 relative to the tips of the gear lock teeth. This may be, for example, an asymmetric profile. In this way, the clearance on either side of the alignment tooth 38 may remain substantially the same, making meshing with the gear teeth 16 less complex.

In an embodiment of the present invention, the park lock system 10 may also include an actuator assembly 46 that, when actuated, urges the gear lock 22 into the locked position.

In further illustration of this embodiment, the actuator assembly 46 may include a press block 51, a self-locking trapezoidal spindle 48, an outer surface of the press block pushing directly on an outer surface of the gear lock portion 22, and an actuator 50 connected to the self-locking trapezoidal spindle 48. The actuator 50 may be configured to rotate the self-locking trapezoidal spindle 48. Self-locking trapezoidal spindle 48 is rotatably connected with a trapezoidal threaded bore in press block 51. When the self-locking trapezoidal spindle 48 rotates in the first direction, it pushes the pressing piece 51 toward and onto the gear locking portion 22, so that the pressing piece 51 pushes the gear locking portion 22 from the release position to the locking position. When the trapezoidal spindle 48 rotates in the direction opposite to the first direction, it pulls the pressing piece 51 away from the gear locking portion 22.

The pressing piece 51 may, for example, engage an outer surface of the gear lock 22 opposite the gear lock teeth 24. In the locking position, the pressing piece 51 is urged against the gear locking portion 22.

By using a self-locking trapezoidal spindle 48, the axial force exerted by the press block 51 on the spindle 48 will not cause the spindle to rotate. This means that the actuator can be used to rotate the spindle 48 and thus translate the press piece 51 into the desired position where the press piece 51 can be held without the actuator 50 exerting a force on the spindle. This will cause the pressure piece 51 to translate in a direction along the first axis 26 only when the actuator 50 rotates the self-locking trapezoidal spindle 48.

The pressing piece 51 is not movable in a direction parallel to the circular line 30, while the gear locking portion 22 is movable along the circular line 30. This means that when the pressing piece 51 is not movable in the direction parallel to the circular line 30, the gear lock portion 22 needs to be movable in the direction relative to the pressing piece 51. This may be done, for example, by arranging the gear lock 22 to slide against the press piece 51. This means, of course, that the biasing device 34 will have to allow the gear lock 22 to slide relative to the pressing piece 51. This also means that the biasing means 34 must be strong enough to overcome the friction between the gear locking portion 22 and the pressing piece 51 when the gear locking portion 22 has not reached the locking position.

Of course, the actuator assembly 46 only has to push the gear lock 22 into the locked position when the vehicle is parked. Only then will the vehicle driveline 12 and gear 14 come to a standstill so that the locking gear part teeth 24 and gear teeth 16 can mesh without risking damage to the park lock system 10. This may be accomplished electronically by ensuring that the actuator only engages the set of

teeth

16, 24 when the vehicle driveline 12 is at rest. In an automatic gear vehicle equipped with a shift-by-wire system (electronic shift system), this can be easily achieved since the rotation of the transmission system has been electronically measured and known.

In another design of the actuator assembly, it may comprise at least one tension spring 44 which pulls the gear lock 22 in the direction of the release position.

In this embodiment, movement of the gear lock 22 along the first axis 26 is made possible by the cooperative engagement of the tension spring 44 and the actuator assembly 46. The former pulls the gear lock 22 into the release position, and the latter pushes the gear lock 22 into the lock position. Of course, the actuator assembly 46 can also be designed such that it can also pull the gear lock 22 into the release position, rendering the tension spring 44 superfluous.

In one embodiment of the present invention, the at least one tension spring 44 also constitutes a biasing means configured to bias the gear locking portion 22 in the initial position and to allow the gear locking portion 22 to move along a portion of the circular line 30.

Combining multiple functions of the park lock system 10 in a single component may provide a simple and elegant design. Fewer components means that the parking lock system 10 will be easier and cheaper to manufacture.

In an embodiment of the present invention, the gear locking teeth 24 are rounded and/or chamfered.

To facilitate the engagement between the gear locking teeth 24 and the gear teeth 16, the profile of the gear locking teeth 24 may be adjusted. Of course, the same is true of gear teeth 16.

In one embodiment of the present invention, the gear lock 22 may be mounted in a gear lock chamber 28 defined by a gear lock housing 54. The gear lock portion housing 54 may be integral with a clutch or transmission housing 56 of the vehicle.

The parking lock system 10 may be implemented as a device having its own gear lock housing 54. The housing may then be mounted in any suitable location adjacent the vehicle driveline 12 so that the gear lock 22 may engage the gear 14. The parking lock system 10 may also be implemented as a device that does not have its own separate gear lock housing 54, but is placed within and is part of the vehicle's clutch or transmission housing 56.

In further illustration of this embodiment of the invention, movement of the gear lock 22 along a portion of the circular line 30 may be limited by a wall of the gear lock housing 54.

When the gear locking portion 22 is engaged with the gear 14, the gear locking portion 22 prevents the gear 14 from moving. In this embodiment, the movement of the gear locking portion 22 is defined by the wall of the gear locking portion housing 54. This means that the gear 14 can move the gear locking portion 22 until the gear locking portion 22 hits the wall of the gear locking portion housing 54. Further movement is not possible.

Another option for preventing the gear locking portion 22 from moving is shown in the examples of fig. 7 to 9. There, the gear lock 22 is provided with cams (bosses) 58, each positioned in an associated cam chamber 60 in the pressure piece 51. In this example, the helical biasing spring 34 engages the cam 58 and a side wall of the cam chamber 60.

Another aspect of the invention provides a vehicle comprising a parking lock system 10 according to the invention.

The various embodiments described above may be used independently of one another and may be combined with one another in various ways. Reference signs used in the detailed description and claims do not limit the description of the embodiments nor the claims. The reference numerals are for illustration only.

Illustration of the drawings

10-parking lock system

12-vehicle transmission system

14-gear

16-gear tooth

18-gear tooth circle

20-radius of gear circle

22-gear locking part

24-Gear Lock section tooth

26-first axis

28-Gear Lock Chamber

30-round line

Radius of 32- (of circular line)

34-biasing means

38-alignment teeth

40- (of gear-locking teeth) tooth tip plane

42-aligned teeth spring

44-tension spring

46-actuator assembly

48-self-locking trapezoidal mandrel

50-actuator

51-briquetting

54-Gear Lock housing

56-a transmission housing;

58-cam

60-cam chamber

Claims

1. A park lock system (10) for a vehicle driveline (12), comprising:

-a gear (14), the gear (14) being coupled to a rotatable member of a transmission system (12), the gear comprising a plurality of circumferentially spaced gear teeth (16), the gear teeth (16) being aligned along a gear tooth circle (18) having a gear circle radius (20); and

-a gear locking portion (22), the gear locking portion (22) comprising a plurality of spaced apart gear locking teeth (24), wherein tips of the gear locking teeth (24) are spaced apart at a pitch of the gear locking teeth,

wherein the gear locking part (22) is movably arranged along a first axis (26) so as to be movable towards and away from the gear (14),

wherein the gear locking portion (22) has a locking position in which the gear locking portion teeth (24) are engaged with the gear teeth (16) such that rotation of the gear (14) is prevented,

wherein the gear lock (22) has a release position in which the gear lock (22) is moved away from the gear (14) such that the gear lock teeth (24) are disengaged from the gear teeth (16) such that the gear (14) can rotate,

wherein the gear locking portion (22) is movably arranged along a portion of a circular line (30) having a radius (32), the radius (32) being substantially equal to the gear circle radius (20),

wherein the gear lock (22) further comprises an alignment tooth (38), a tip of the alignment tooth (38) being tangentially offset with respect to the tip of the gear lock tooth, and

wherein the alignment teeth (38) have a protruding position wherein the tips of the alignment teeth (38) protrude beyond the tips of the gear locking teeth (24) towards the gear wheel (14).

2. Parking lock system according to claim 1, wherein the gear lock (22) is movable in two directions along a part of the circular line (30).

3. Parking locking system according to claim 1 or 2, wherein the gear lock (22) comprises an annular body and wherein the gear lock teeth (24) are spaced along the entire circle.

4. Parking lock system according to any of the preceding claims, further comprising a biasing means (34), the biasing means (34) being configured for biasing the gear lock (22) in an initial position and allowing the gear lock (22) to move along a part of the circular line (30).

5. Parking lock system according to claim 4, wherein the biasing means (34) comprises at least one biasing spring (34) urging the gear lock (22) into the initial position, and wherein the at least one biasing spring (34) allows a movement of the gear lock (22) in a direction along a part of the circular line (30).

6. The alignment tooth (38) is movable relative to the gear lock tooth (24) in a direction substantially parallel to the first axis (26).

7. Parking locking system according to claim 6, wherein the alignment tooth (38) is movable between an aligned position in which the tip of the alignment tooth (38) is aligned with the tip of the gear lock tooth (22) in the tooth top plane (40) of the gear lock tooth (24) and a protruding position.

8. Parking lock system according to claim 7, wherein the parking lock system (10) further comprises an alignment tooth spring (42) urging the alignment tooth (38) into the protruding position.

9. Parking lock system according to claim 8, wherein the aligning tooth spring (42) is provided in the gear locking part (22).

10. Parking locking system according to any one of the preceding claims, wherein the profile of the alignment teeth (38) is different from the profile of the gear locking teeth (24).

11. Parking locking system according to any one of the preceding claims, wherein said alignment tooth (38) has an asymmetrical profile.

12. The parking lock system as recited in any one of the preceding claims, further comprising:

-an actuator assembly (46), the actuator assembly (46) urging the gear lock (22) into the locked position when actuated.

13. Parking locking system according to claim 12, wherein said actuator assembly (46) comprises:

-a pressing piece (51), an outer surface of the pressing piece (51) pushing directly on an outer surface of the gear locking portion (22);

-a self-locking trapezoidal spindle (48);

-an actuator (50), said actuator (50) being connected to said self-locking trapezoidal spindle (48) and configured to rotate said self-locking trapezoidal spindle (48);

wherein the self-locking trapezoidal spindle (48) is rotationally connected with a trapezoidal threaded hole in the pressing block (51),

wherein the rotating self-locking trapezoidal spindle (48) pushes the press piece (51) in a first direction towards the gear lock (22) and onto the gear lock (22) such that the press piece (51) pushes the gear lock (22) from the release position to the lock position, and

wherein the trapezoidal spindle (48) rotating in a direction opposite to the first direction pulls the pressing piece (51) away from the gear locking portion (22).

14. The parking lock system as recited in claim 12 or 13, wherein said actuator assembly comprises:

-at least one tension spring (44), which tension spring (44) pulls the gear lock (22) in the direction of the release position.

15. Parking lock system according to claim 14 and at least as dependent on claim 4, wherein said at least one tension spring (44) further constitutes said biasing means configured for biasing said gear lock (22) in an initial position and allowing movement of said gear lock (22) along a portion of said circular line (30).

16. Parking locking system according to any one of the preceding claims, wherein the gear locking teeth (24) are rounded.

17. Parking locking system according to any one of the preceding claims, wherein the gear locking teeth (24) are chamfered.

18. Parking locking system according to any of the preceding claims, wherein the gear lock (22) is mounted in a gear lock chamber (28) delimited by a gear lock housing (54).

19. The parking lock system as recited in claim 18, characterized in that movement of said gear lock (22) along said portion of said circular line (30) is limited by a wall of said gear lock housing (54).

20. Parking lock system according to claim 18 or 19, wherein the gear lock housing (54) is integrated with a clutch or transmission housing (56) of a vehicle.

21. Vehicle comprising a parking lock system (10) according to any one of the preceding claims.