# US 8,770,057 B2 · Device for emergency release of an automotive parking interlock > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,770,057 B2 - Document ID: US8770057B2 - Status: Granted - Kind: B2 - Application number: 12/840,418 - Filed: 2010-07-21 - Published: 2011-02-10 - Granted: 2014-07-08 - Earliest claimed: 2009-08-07 - Assignees: ZF Friedrichshafen AG - Applicants: Christian Ruhl - Inventors: Christian Ruhl - Web page: https://patentgrep.com/patent/US8770057B2 ## CPC - F16H 63/3491: {Emergency release or engagement of parking locks or brakes} - Y10T 74/20098: Separate actuator to disengage restrictor - Y10T 74/20104: Shift element interlock - F16H: GEARING - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The mechanism for emergency release of a parking lock of an automatic transmission. The mechanism comprises and is connected, in a rotationally fixed manner, with the selector shaft (1) of the shifting device of the transmission. A lever (2), which is positioned facing the transmission housing (3), at the side of the shifting device, can be activated by an unlocking tool (5) that is inserted from the outside through an opening (4) in the transmission housing (3) to release the parking lock. ## Claims ### Claim 1 An automatic transmission parking lock emergency release mechanism being accommodated within an automatic transmission, and the automatic transmission including a shifting device with a selector shaft (1), the emergency release mechanism comprising a lever (2) being connected, in a rotationally fixed manner, to the selector shaft (1) of the shifting device of the automatic transmission and the lever (2) being positioned adjacent a side of a transmission housing (3), and the lever (2) is accommodated outside the transmission housing; a pivotable end of the lever (2) being positioned directly facing and adjacent an opening (4) in the transmission housing (3) adjacent a side of the shifting device: and the pivotable end of the lever (2) being activatable by direct engagement with a leading end of a rotatable unlocking tool (5) to facilitate release of the parking lock, and the rotatable unlocking tool (5) only being inserted through the opening of the transmission housing (3), from outside of the transmission housing (3), so as to directly engage with and push the pivotable end of the lever (2) away from the opening (4) and releases the parking lock when emergency release of the parking lock is desired, and rotation of the rotatable unlocking tool (5), relative to the opening (4) of the transmission housing (3), further inserts the leading end of the unlocking tool through the opening (4) and induces engagement with and pushes the pivotable end of the lever (2) and causes rotation of the pivotable end of the lever (2) away from the opening (4) which releases the parking lock. ### Claim 2 (depends on 1) The automatic transmission parking lock emergency release mechanism according to claim 1, further comprising that the unlocking tool (5) is a threaded pin which has an external thread that can be screwed into the opening (4) of the transmission housing (3) which is provided a mating thread so that an end of the threaded pin (5), adjacent the lever (2), causes a rotational motion of the lever (2) whereby, after rotation of the lever by a certain angle, the parking lock is released. ### Claim 3 (depends on 1) The automatic transmission parking lock emergency release mechanism according to claim 1, further comprising that the opening (4) of the transmission housing (3) is located adjacent a vertically lower portion of a vehicle which incorporates the transmission, and an underbody covering is provided, in an area of the opening (4), and the underbody cover has a tool operated service lid to enable the access to the opening (4) of the transmission enclosure. ### Claim 4 An automatic transmission parking lock emergency release mechanism, the mechanism comprising: a lever (2) being accommodated outside a transmission housing and supported by and being located adjacent a side of the transmission housing (3) of the automatic transmission, and the lever (2) being connected, in a rotationally fixed manner, to a selector shaft (1) of a shifting device while a pivotable end of the lever (2) being normally unconnected with an unlocking tool (5), the lever (2) facing a threaded opening (4) of the transmission housing (3), the threaded opening (4) of the transmission housing (3) facilitates direct engagement of and pushing of the pivotable end of the lever (2) with a leading end of the unlocking tool (5) having a mating threaded exterior, and the threaded opening (4) in the transmission housing (3) being aligned with the pivotable end of the lever (2) such that, only when the unlocking tool (5) is threaded into and through the threaded opening (4) of the transmission housing (3), the unlocking tool (5) directly contacts and pushes the pivotable end of the lever (2) and pivots the lever (2) away from the opening (4) to a desired angle of rotation which rotates and deactivates the parking lock. ### Claim 5 (depends on 4) The automatic transmission parking lock emergency release mechanism according to claim 4, wherein an underbody covering covers the threaded opening (4) and comprises a service lid which facilitates access to the threaded opening (4) of the transmission housing (3). ### Claim 6 (depends on 4) The automatic transmission parking lock emergency release mechanism according to claim 4, wherein the pivot force, exerted on the lever (2), is provided without a Bowden cable. ### Claim 7 (depends on 1) The automatic transmission parking lock emergency release mechanism according to claim 1, wherein the unlocking tool (5) is removable and facilitates accesses to the inside the transmission housing (3) from outside the transmission. ### Claim 8 (depends on 1) The automatic transmission parking lock emergency release mechanism according to claim 1, wherein the unlocking tool (5) is normally located out of engagement with the threaded opening (4) and exerts a pushing force on the lever (2) to release the parking lock only when engaged with the threaded opening (4). ### Claim 9 An automatic transmission parking lock emergency release mechanism, the mechanism comprising: a lever (2) being supported by and located adjacent a side of a transmission housing (3) of the automatic transmission and being connected, in a rotationally fixed manner, to a selector shaft (1) of a shifting device while a pivotable end of the lever (2) being normally completely disconnected with an unlocking tool (5), and the lever (2) being accommodated outside the transmission housing the pivotable end of the lever (2) facing a threaded opening (4) of the transmission housing (3), the threaded opening (4) of the transmission housing (3) facilitating direct engagement of the pivotable end of the lever (2) with a leading threaded end of the unlocking tool (5), and the pivotable end of the lever (2) being aligned with the threaded opening (4) to facilitate a pivoting movement of the lever, away from the threaded opening due to engagement with the leading end of the unlocking tool (5), and actuation of the lever (2), and the threaded opening (4) in the transmission housing (3) being located closely adjacent and aligned with the pivotable end of the lever (2) such that only when the leading end of the unlocking tool (5) is threaded into and through the threaded opening (4), located outside of the transmission housing (3) rotation of the unlocking tool (5), relative to the threaded opening (4), causing the leading end of the unlocking tool (5) to be brought into direct contact with and push the pivotable end of the lever (2) and pivot the lever (2) away from the threaded opening to a desired angle of rotation which deactivates the parking lock.