DE102013213474B4 - Parking lock for a transmission - Google Patents

Abstract

Parking lock (2) for a transmission (1), in particular an automatic transmission or a fully or partially automated manual transmission, of a motor vehicle, comprising - a locking element (4) which can be connected to an output shaft (3) of the transmission (1) and - a pawl (6 ), the locking pawl (6) between a locking position in which the locking pawl (6) is in locking engagement with the locking element (4) and a release position in which the locking pawl (6) is not in locking engagement with the locking element (4 ), is movably mounted to and fro, - the pawl (6) is subjected to force in the direction of its release position, characterized by - a shift drum (10), on the outside of which a guide contour (11) is formed, and - on that of the locking element (4) facing away from the pawl (6) arranged actuator (13), which is linear between an engaged position and a disengaged position on an axis radial to the shift drum (10) movably supported and in the direction of its disengaged position by means of a compression spring (14), - the actuator (13) engages in the guide contour (11) of the shift drum (10) when the actuator (13) is in its disengaged position is located, - on the outside of the actuator (13) a guide contour (15) is formed, with which the pawl (6) is in constant contact, and - wherein the guide contour (15) of the actuator (13) is designed such that the pawl (6) is in its locking position when the actuator (13) is in its disengaged position and that the locking pawl (6) is in its release position when the actuator (13) is in its engaged position.

Description

The invention relates to a parking lock for a transmission, in particular an automatic transmission or a fully or partially automated manual transmission, of a motor vehicle. Furthermore, the invention relates to a transmission, in particular automatic transmission or fully or partially automated manual transmission, for a motor vehicle.

Parking locks are used in particular in motor vehicles which are equipped with an automatic transmission or a fully or partially automated manual transmission. With purely manual transmissions, no parking lock is usually provided. However, a parking lock can also be provided in the case of a purely manual transmission, as described, for example, by the published patent application DE 197 10 975 A1 is disclosed.

It is known for example from the FR 2 964 925 A1 , of the EP 2 275 719 A1 or the post-published DE 10 2012 012 673 A1 to form a parking lock as a mechanical locking device. In this case, a pawl is usually present, which can engage in a locking wheel which is connected in a rotationally fixed manner to an output shaft of the transmission in order to form the parking lock function. To open the parking lock, an additional release device is usually required with which the parking lock can be unlocked.

Motor vehicles with a purely manual transmission without a parking lock are generally secured against rolling away by means of a parking brake and by engaging a gear. In vehicles with a continuously variable fully automatic transmission (Variomatic transmission), a centrifugal clutch and a downstream manual transmission, such as off-road vehicles ("All Terrain Vehicle"; ATV) and motor scooters ("scooters"), no one can lock the transmission when the engine is stopped Gear must be engaged because the centrifugal clutch is open when the engine is stopped. Therefore, parking brakes arranged on the rear wheels are conventionally used to form a parking lock in such vehicles. For this purpose, expensive parking brake calipers must be arranged on the rear wheels, which also disadvantageously increase the unsprung mass of the rear wheels. In contrast, the arrangement of a parking lock designed as a mechanical locking device in a transmission is preferred. However, conventional parking locks have relatively complex actuating devices constructed from a large number of individual parts, which require a relatively large amount of installation space and are particularly difficult to reconcile with the use of an axially displaceable shift drum of the transmission.

The object of the invention is to provide a new type of parking lock, which can be implemented inexpensively and requires a small installation space.

This object is achieved by a parking lock with the features according to claim 1 and a transmission with the features according to claim 8. Advantageous refinements are given in the subclaims, which can be taken individually or in various combinations with one another to represent an aspect of the invention.

• - ein mit einer Abtriebswelle des Getriebes verbindbares Sperrelement und
• - eine Sperrklinke, wobei die Sperrklinke zwischen einer Sperrstellung, in der sich die Sperrklinke in Sperreingriff mit dem Sperrelement befindet, und einer Freigabestellung, in der sich die Sperrklinke nicht in Sperreingriff mit dem Sperrelement befindet, hin und her bewegbar gelagert ist,
• - wobei die Sperrklinke in Richtung ihrer Freigabestellung mit Kraft beaufschlagt ist, gekennzeichnet durch
• - eine Schaltwalze, an deren Außenseite eine Führungskontur ausgebildet ist, und
• - ein auf der dem Sperrelement abgewandten Seite der Sperrklinke angeordnetes Stellglied, das zwischen einer eingerückten Stellung und einer ausgerückten Stellung linear auf einer zur Schaltwalze (10) radialen Achse beweglich gelagert und in Richtung seiner ausgerückten Stellung mittels einer Druckfeder (14) mit Kraft beaufschlagt ist,
• - wobei das Stellglied in die Führungskontur der Schaltwalze eingreift, wenn sich das Stellglied in seiner ausgerückten Stellung befindet,
• - wobei an der Außenseite des Stellglieds eine Führungskontur ausgebildet ist, mit welcher die Sperrklinke in ständigem Kontakt steht, und
• - wobei die Führungskontur des Stellglieds derart ausgebildet ist, dass sich die Sperrklinke bei in seiner ausgerückten Stellung befindlichem Stellglied in ihrer Sperrstellung befindet und dass sich die Sperrklinke bei in seiner eingerückten Stellung befindlichem Stellglied in ihrer Freigabestellung befindet.

According to claim 1, the parking lock mentioned above

• - A locking element connectable to an output shaft of the transmission and
• a locking pawl, the locking pawl being movably reciprocated between a locking position in which the locking pawl is in locking engagement with the locking element and a release position in which the locking pawl is not in locking engagement with the locking element,
• - wherein the pawl is acted upon in the direction of its release position, characterized by
• - A shift drum, on the outside of which a guide contour is formed, and
• - An actuator arranged on the side of the pawl facing away from the locking element, which is linear between an engaged position and a disengaged position on a to the shift drum ( 10th ) movable radial axis and in the direction of its disengaged position by means of a compression spring ( 14 ) is loaded with force,
• the actuator engages in the guide contour of the shift drum when the actuator is in its disengaged position,
• - A guide contour is formed on the outside of the actuator, with which the pawl is in constant contact, and
• - The guide contour of the actuator is designed such that the pawl is in its disengaged position when the actuator is in its disengaged position and that the pawl is in its released position when the actuator is in its engaged position.

In contrast to conventional parking locks, the parking lock according to the invention can be implemented using a few components, as a result of which the parking lock according to the invention is also less prone to repair. This is with one Cost reduction and weight reduction combined. In addition, less installation space is required.

A shift drum is a common part of a transmission. The shift drum of the parking lock according to the invention replaces such a conventional shift drum, so that the shift drum of the parking lock according to the invention can be arranged in a transmission without additional space to be provided. In addition to a new production of a transmission with the parking lock according to the invention, it is therefore possible to easily retrofit an already existing transmission with the parking lock according to the invention.

By rotating the shift drum about its longitudinal axis and the guide contour formed on it, the actuator can be moved back and forth linearly between its engaged position and its disengaged position. By means of these linear movements of the actuator and the guide contour arranged on the actuator, with which the pawl is in constant contact, the pawl can be moved back and forth between its locking position and its release position. The shift drum can be operated via an actuator, which consequently also operates the pawl and thus the entire parking lock.

According to an advantageous embodiment, the guide contour of the shift drum is designed as a groove aligned parallel to and at a distance from the longitudinal axis of the shift drum. As a result, the shift drum can interact with the actuator regardless of whether or not the shift drum is displaced in the direction of its longitudinal axis due to the transition between different transmission states. Preferably, the longitudinal edges of the groove flow smoothly into the remaining surface of the shift drum in order to be able to force the actuator out of the groove with the least possible force when the shift drum rotates about its longitudinal axis.

According to a further advantageous embodiment, the actuator is cylindrical with a tapered diameter, the tapered diameter forming at least part of the guide contour of the actuator. This represents a simple design of the guide contour of the actuator, it being irrelevant for the function of this actuator if it is rotated about its longitudinal axis. This is reflected in a reduction in the effort required to operate the parking lock.

A further advantageous embodiment provides that the section of the actuator which interacts with the shift drum has a shape which is complementary to the shaping of the guide contour of the shift drum on its side facing the shift drum. A positive fit can be achieved in this way in order to improve the robustness of the parking lock against unintentional loosening.

It is furthermore considered to be advantageous if the pawl has a locking lug on its side facing the locking element and an adjusting lug on its side facing the actuator. The locking lug can be brought into engagement with locking receptacles arranged on the locking element. The control lug, however, is in constant contact with the guide contour of the actuator.

In a further advantageous embodiment, the pawl is acted upon by a leg spring in the direction of its release position. This ensures that the pawl is securely and permanently in its release position when the actuator is in its engaged position.

The actuator is advantageously acted upon by a compression spring in the direction of its disengaged position. The compression spring generates a pretension, in particular in the event that the pawl cannot engage directly in the locking element when the parking lock is activated, which can be caused, for example, by a tooth-on-tooth position. Using the design of the compression spring and the geometric properties of the actuator, the parking lock can be designed in such a way that the locking pawl is rejected by the locking element above a predeterminable limit speed and the transmission is not blocked.

It is also proposed that the locking element is designed as a locking wheel. The ratchet wheel is preferably aligned radially to the output shaft of the transmission, with which it is connected in a rotationally fixed manner.

According to claim 8, the transmission of the type mentioned has a parking lock according to one of the aforementioned configurations or any combination thereof. This is associated with the advantages mentioned above with regard to the parking lock.

According to an advantageous embodiment, the locking element is connected in a rotationally fixed manner to a gearwheel of the transmission which is connected in a rotationally fixed manner to the output shaft. In contrast to a separate arrangement of the blocking element on the output shaft, this is accompanied by a space-saving arrangement of the blocking element on the output shaft.

• 1 eine schematische Ausschnittdarstellung einer beispielhaften Ausführungsform eines erfindungsgemäßen Getriebes.

In the following, the invention is explained by way of example with reference to the attached figure using a preferred exemplary embodiment, the features shown below being able to represent an aspect of the invention both individually and in different combinations with one another. It shows:

• 1 is a schematic sectional view of an exemplary embodiment of a transmission according to the invention.

1 shows a schematic detail representation of an exemplary embodiment of a transmission according to the invention 1 of a motor vehicle, not shown, wherein the transmission is a parking lock 2nd having.

The parking lock 2nd includes one with an output shaft 3rd of the transmission 1 connected, designed as a ratchet locking element 4th , the rotatable with a rotatable with the output shaft 3rd connected gear 5 of the transmission 1 connected is. The transmission also includes 1 a pawl 6 between the shown locking position, in which the pawl 6 in locking engagement with the locking element 4th is, and a release position in which the pawl 6 not in locking engagement with the locking element 4th located, is movable back and forth. To the pawl 6 in locking engagement with the locking element 4th To bring, has the locking element 4th extensive six lock shots 7 on. The pawl 6 is by means of a leg spring 8th is applied in the direction of its release position with force, the leg spring 8th on a pen 9 is arranged with a housing of the transmission, not shown 1 connected is.

The parking lock 2nd also has a shift drum 10th on, on the outside of a guide contour 11 is formed as parallel to and spaced from the vertical axis perpendicular to the sheet plane 12th the shift drum 10th aligned groove is formed.

The parking lock also points 2nd one on the the locking element 4th opposite side of the pawl 6 arranged actuator 13 on the linearly movably mounted between an engaged position and the disengaged position shown and in the direction of its disengaged position by means of a compression spring 14 is loaded with force. The actuator 13 reaches into the guide contour 11 the shift drum 10th a because the actuator 13 in its disengaged position. On the outside of the actuator 13 is a guiding contour 15 trained with which the pawl 6 is in constant contact. The actuator 13 is cylindrical with a diameter taper 16 trained, the diameter taper 16 part of the guide contour 15 of the actuator 13 trains. The guide contour 15 of the actuator 13 is designed such that the pawl 6 with the actuator in its disengaged position 13 , as shown, is in its locked position and that the pawl 6 with the actuator in its engaged position 13 is in its release position. The pawl 6 points to the blocking element 4th facing side a locking lug 17th and on their the actuator 13 facing side an adjusting lug 18th on. The one with the shift drum 10th cooperating section 19th of the actuator 13 points to its the shift drum 10th facing side one for shaping the guide contour 11 the shift drum 10th complementary shape.

Reference list

1

transmission

2nd

Parking lock

3rd

Output shaft

4th

Locking element

5

gear

6

Pawl

7

Lock recording

8th

Leg spring

9

pen

10th

Shift drum

11

Guide contour

12th

Longitudinal axis

13

Actuator

14

Compression spring

15

Guide contour

16

Diameter taper

17th

Locking nose

18th

Nose

19th

section

Claims (9)

Parking lock (2) for a transmission (1), in particular an automatic transmission or a fully or partially automated manual transmission, of a motor vehicle, comprising - a locking element (4) which can be connected to an output shaft (3) of the transmission (1) and - a pawl (6 ), the locking pawl (6) between a locking position in which the locking pawl (6) is in locking engagement with the locking element (4) and a release position in which the locking pawl (6) is not in locking engagement with the locking element (4 ), is mounted to move back and forth, - the pawl (6) being acted upon in the direction of its release position, characterized by - a shift drum (10), on the outside of which a guide contour (11) is formed, and - an actuator (13) arranged on the side of the pawl (6) facing away from the locking element (4), which is linear between an engaged position and a disengaged position is movably mounted on an axis that is radial to the shift drum (10) and is subjected to force in the direction of its disengaged position by means of a compression spring (14), - the actuator (13) engaging in the guide contour (11) of the shift drum (10) when the actuator (13) is in its disengaged position, - a guide contour (15) is formed on the outside of the actuator (13) with which the pawl (6) is in constant contact, and - wherein the guide contour (15) of the Actuator (13) is designed such that the pawl (6) is in its locked position when the actuator (13) is in its disengaged position and that the pawl (6 ) is in its release position when the actuator (13) is in its engaged position. Parking lock (2) after Claim 1 , characterized in that the guide contour (11) of the shift drum (10) is designed as a groove aligned parallel to and at a distance from the longitudinal axis (12) of the shift drum (10). Parking lock (2) after Claim 1 or 2nd , characterized in that the actuator (13) is cylindrical with a diameter taper (16), the diameter taper (16) forming at least part of the guide contour (15) of the actuator (13). Parking lock (2) according to one of the preceding claims, characterized in that the portion (19) of the actuator (13) which interacts with the shift drum (10) on its side facing the shift drum (10) has a shape for shaping the guide contour (11) of the shift drum (10) has a complementary shape. Parking lock (2) according to one of the preceding claims, characterized in that the pawl (6) has a locking lug (17) on its side facing the locking element (4) and a locking lug (18) on its side facing the actuator (13). Parking lock (2) according to one of the preceding claims, characterized in that the pawl (6) is acted upon by means of a leg spring (8) in the direction of its release position. Parking lock (2) according to one of the preceding claims, characterized in that the locking element (4) is designed as a locking wheel. Transmission (1), in particular automatic transmission or fully or partially automated manual transmission, for a motor vehicle, characterized by at least one parking lock (2) according to one of the preceding claims. Transmission (1) after Claim 8 , characterized in that the locking element (4) is non-rotatably connected to a non-rotatably connected to the output shaft (3) gear (5) of the transmission (1).

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