# US 10,501,057 B2 · Parking lock pre-selection system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,501,057 B2 - Document ID: US10501057B2 - Status: Granted - Kind: B2 - Application number: 15/542,342 - Filed: 2016-01-06 - Published: 2018-09-27 - Granted: 2019-12-10 - Earliest claimed: 2015-01-07 - Assignees: CNH Industrial America LLC - Applicants: CNH Industrial America LLC - Inventors: Enrico Conti - Web page: https://patentgrep.com/patent/US10501057B2 ## CPC - B60T 1/005: {by locking of wheel or transmission rotation} - F16D 63/006: {Positive locking brakes} - F16H 63/34: Locking or disabling mechanisms - F16D 2121/14: Mechanical - F16H 51/00: Levers of gearing mechanisms - F16H 63/3433: {Details of latch mechanisms, e.g. for keeping pawls out of engagement} - B60T: VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL (electrodynamic brake systems for vehicle, in general B60L; brakes per se, i.e. devices where braking effect occurs, including ultimate brake actuators, F16D); ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES - F16H: GEARING ## Abstract A parking lock pre-selection mechanism for a work machine is disclosed in which a pawl is engageable with teeth on a power train output shaft to lock it in place. An operator lever is used to preselect the parking lock position. The mechanism includes first and second pivotally interconnected links, urged by a spring to a maximum length set by a stop. The spring causes the pawl to be urged into place when the teeth and pawl are in proper alignment. ## Claims ### Claim 1 An operator controlled parking lock actuation system for a work machine in which a parking lock mechanism is engaged by displacement of a lever, the system comprising: a first link having a first end connected to an operator selection mechanism; a second link pivotally connected to the first link at a point in between the ends of the first and second links, the second link having a first end connected to the lever of the parking lock mechanism; a spring interconnected between the first and second links to yieldably urge the first and second links to an elongated state; and an adjustable stop on one of the first and second links to limit the elongated state to a length causing displacement of the lever and engagement of the parking lock mechanism, wherein the adjustable stop is a screw threaded into one of the first and second links and abutting the other of the first and second links. ### Claim 2 (depends on 1) The parking lock actuation system as claimed in claim 1, wherein the spring has a sufficient spring force to overcome system friction forces to engage the parking lock mechanism. ### Claim 3 (depends on 1) The parking lock actuation system as claimed in claim 1, wherein the first link is longer than the second link. ### Claim 4 (depends on 3) The parking lock actuation system as claimed in claim 3, wherein the first link has a straight section and an integral curved section, the second link being pivotally mounted to the first link in the curved section so that the first end of the second link connecting to the parking lock mechanism is generally in line with the straight section. ### Claim 5 A power train, comprising: a rotatable output shaft having a plurality of teeth around its periphery; a pawl displaceable into and out of a space between the teeth on the shaft to engage one of the teeth; a rocker arm pivotally mounted to displace the pawl into and out of engagement by pivoting; a mechanism for translating displacement into rotation of the rocker arm; an operator selection mechanism including a fixed position for a parking lock selection and including a crank arm; a first link having a first end; a second link pivotally connected to the first link at a point in between the ends of the first and second links, the second link having a first end; a spring interconnected between the first and second links to yieldably urge the first and second links to an elongated state; and the first end of each of the first and second links being connected to the rocker arm displacement mechanism and to the crank arm of the operator selection mechanism; whereby the operator selection mechanism is operable to be moved to the parking lock position and, if the pawl interferes with the teeth, is urged to engagement when the output shaft is rotated to clear the teeth; an adjustable stop on one of the first and second links operable to limit the elongated state to a length causing displacement of the lever and engagement of the pawl, wherein the adjustable stop is a screw threaded into one of the first and second links and abutting the other of the first and second links. ### Claim 6 (depends on 5) The power train as claimed in claim 5, wherein the rocker arm displacement mechanism for the pawl comprises a cam surface mounted on a rotatable cam support shaft and having a contour that rotation of the cam surface urges the pawl into engagement and the cam surface is actuated by a lever to which one of the first ends of the first and second links is connected. ### Claim 7 (depends on 5) The power train as claimed in claim 5, wherein the spring has a sufficient spring force to overcome system friction forces to engage the pawl. ### Claim 8 (depends on 5) The power train as claimed in claim 5, wherein the first link is longer than the second link. ### Claim 9 (depends on 8) The power train as claimed in claim 8, wherein the first link has a straight section and an integral curved section, the second link being pivotally mounted to the first link in the curved section so that its end connecting to the rocker arm displacement mechanism is generally in line with the straight section.