Patent ID: 12253169

DETAILED DESCRIPTION

While the concepts of the present disclosure are susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will be described herein in detail. It should be understood, however, that there is no intent to limit the concepts of the present disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives consistent with the present disclosure and the appended claims.

References in the specification to “one embodiment,” “an embodiment,” “an illustrative embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may or may not necessarily include that particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. Additionally, it should be appreciated that items included in a list in the form of “at least one A, B, and C” can mean (A); (B); (C); (A and B); (A and C); (B and C); or (A, B, and C). Similarly, items listed in the form of “at least one of A, B, or C” can mean (A); (B); (C); (A and B); (A and C); (B and C); or (A, B, and C).

In the drawings, some structural or method features, such as those representing devices, modules, instructions blocks and data elements, may be shown in specific arrangements and/or orderings for ease of description. However, it should be appreciated that such specific arrangements and/or orderings may not be required. Rather, in some embodiments, such features may be arranged in a different manner and/or order than shown in the illustrative figures. Additionally, the inclusion of a structural or method feature in a particular figure is not meant to imply that such feature is required in all embodiments and, in some embodiments, may not be included or may be combined with other features.

In some embodiments, schematic elements used to represent blocks of a method may be manually performed by a user. In other embodiments, implementation of those schematic elements may be automated using any suitable form of machine-readable instruction, such as software or firmware applications, programs, functions, modules, routines, processes, procedures, plug-ins, applets, widgets, code fragments and/or others, for example, and each such instruction may be implemented using any suitable programming language, library, application programming interface (API), and/or other software development tools. For instance, in some embodiments, the schematic elements may be implemented using Java™, C++™, and/or other programming languages. Similarly, schematic elements used to represent data or information may be implemented using any suitable electronic arrangement or structure, such as a register, data store, table, record, array, index, hash, map, tree, list, graph, file (of any file type), folder, directory, database, and/or others, for example.

Further, in the drawings, where connecting elements, such as solid or dashed lines or arrows, are used to illustrate a connection, relationship, or association between or among two or more other schematic elements, the absence of any such connection elements is not meant to imply that no connection, relationship, or association can exist. In other words, some connections, relationships, or associations between elements may not be shown in the drawings so as not to obscure the disclosure. In addition, for ease of illustration, a single connecting element may be used to represent multiple connections, relationships, or associations between elements. For example, where a connecting element represents a communication of signals, data or instructions, it should be understood by those skilled in the art that such element may represent one or multiple signal paths (e.g., a bus), as may be needed, to effect the communication.

Referring now toFIG.1, an illustrative drive system100for a vehicle includes a transmission120. The transmission120is configured to receive rotational power supplied by a drive unit102and provide the rotational power to an illustrative load (e.g., an axle132and wheels134A,134B mounted thereto) in use thereof. The transmission120includes an input shaft122, an output shaft124, and a park system200(seeFIG.2). The input shaft122includes, or is otherwise embodied as, any structure or collection of structures configured to receive torque/rotational power from the drive unit102. The output shaft124includes, or is otherwise embodied as, any structure or collection of structures configured to transmit torque/rotational power from the input shaft122to a load, which, in addition to the axle132and the wheels134A,134B, may include one or more transaxles, differentials, transfer boxes, final drives, and/or wheels, for example. As will be apparent from the discussion that follows, the park system200is configured to selectively brake the output shaft124during a park operational mode of the transmission120.

Referring now toFIGS.2and3, the illustrative park system200includes a park assembly or park gear assembly210. At least in some embodiments, the park assembly210includes a structure (e.g., a gear) arranged in contact with the output shaft124. In some embodiments, the structure may at least partially receive the output shaft124such that inner teeth or splines of the structure (not shown) mate or mesh with corresponding features (e.g., grooves, notches, recesses, channels, or the like) of the output shaft124. In any case, it should be appreciated that complementary features of the structure and the output shaft124couple the structure and the output shaft124for common rotation and/or lack thereof.

The illustrative park system200includes an electro-hydraulic valve assembly220coupled to the park assembly210. The electro-hydraulic valve assembly220includes, or is otherwise embodied as, a collection of structures operable in combination with one another to deliver one or more fluid pressures to a piston270of an actuation linkage230of the park system200, as described in greater detail below. In the illustrative embodiment, the electro-hydraulic valve assembly220includes a valve element or spool822(seeFIG.8) that is movable to selectively supply hydraulic fluid pressure to the piston270. Therefore, the illustrative electro-hydraulic valve assembly220includes an electro-hydraulic valve824configured to deliver fluid pressure to the piston270in response to one or more control signals issued to the valve assembly220(i.e., a solenoid thereof) by a control system.

The park system200illustratively includes the actuation linkage230coupled between the electro-hydraulic valve assembly220and the park gear assembly210. The piston270of the actuation linkage230is axially translatable along a longitudinal axis LA in response to the one or more fluid pressures delivered thereto from the electro-hydraulic valve assembly220, as further discussed below. As will be apparent from the discussion that follows, the actuation linkage230includes a number of mechanical and/or electro-mechanical structures that cooperate to operatively couple the electro-hydraulic valve assembly220to the park assembly210. Consequently, in use of the transmission120, the electro-hydraulic valve assembly220drives operation of the park assembly210through the actuation linkage230to establish a plurality of operating states of the park system200. In particular, through the coupling established by the actuation linkage230, translation of the piston270along the longitudinal axis LA drives operation of the park assembly210in an engaged state1300(seeFIG.13) and in a disengaged state1500(seeFIG.15). In the engaged state1300, the park assembly210constrains rotation of the structure/gear with a park pawl312to resist rotation of the output shaft124. In the disengaged state1500, the park assembly210allows rotation of the structure/gear to permit rotation of the output shaft124in a non-park operating mode of the transmission120.

The illustrative actuation linkage230includes a plate240pivotally coupled to the piston270. Through the pivotal coupling, movement of the piston270along the longitudinal axis LA causes rotation of the plate240about a rotational axis RA as shown inFIGS.13and15. The actuation linkage230also includes a biasing element250that surrounds the rotational axis RA and applies a biasing force BF to the plate240to urge interaction between the plate240and the piston270in the engaged state1300and in the disengaged state1500of the park system200. In the illustrative embodiment, the biasing element250is wound around a sleeve1260of the actuation linkage230such that the biasing element250is at least partially retained around the rotational axis RA by the sleeve1260. As further discussed below, the sleeve1260is configured for linear movement along the rotational axis RA in use of the park system200.

The park system200of the present disclosure relies on a hydraulic system2750(seeFIG.27) including the electro-hydraulic valve assembly220and other devices discussed below to drive operation of the park assembly210in the aforementioned operational states. In some embodiments, the hydraulic system2750may be employed as a substitute or replacement for a cable-actuated parking mechanism. In such embodiments, it should be appreciated that a cable-actuated parking mechanism may be omitted entirely.

In the illustrative embodiment, the transmission120includes a control system2700(seeFIG.27) that is configured to control operation of various components of the transmission120(e.g., one or more clutches and an electro-hydraulic system138) and operation of the park system200(e.g., the electro-hydraulic valve assembly220and various other devices included in the hydraulic system2750). The control system2700includes a controller2702that is communicatively coupled to various electro-mechanical components of the park system200, among other things. Methods and/or activities that may be performed by the controller2702to control operation of the park system200and the transmission120are described in greater detail below with reference toFIGS.28-32.

Referring again toFIG.1, it should be appreciated that the illustrative transmission120, and the drive system100incorporating the transmission120, are adapted for use in one or more vehicles employed in a variety of applications. In some embodiments, the transmission120may be adapted for use with, or otherwise incorporated into, fire and emergency vehicles, refuse vehicles, coach vehicles, RVs and motorhomes, municipal and/or service vehicles, agricultural vehicles, mining vehicles, specialty vehicles, energy vehicles, defense vehicles, port service vehicles, construction vehicles, and transit and/or bus vehicles, just to name a few. Additionally, in some embodiments, the transmission120may be adapted for use with, or otherwise incorporated into, tractors, front end loaders, scraper systems, cutters and shredders, hay and forage equipment, planting equipment, seeding equipment, sprayers and applicators, tillage equipment, utility vehicles, mowers, dump trucks, backhoes, track loaders, crawler loaders, dozers, excavators, motor graders, skid steers, tractor loaders, wheel loaders, rakes, aerators, skidders, bunchers, forwarders, harvesters, swing machines, knuckleboom loaders, diesel engines, axles, planetary gear drives, pump drives, transmissions, generators, and marine engines, among other suitable equipment.

In the illustrative embodiment, the transmission120includes one or more clutches (not shown). The one or more clutches may be included in, or otherwise adapted for use with, the electro-hydraulic system138and coupled between the input shaft122and the output shaft124to selectively transmit rotational power between the shafts122,124in one or more operating modes of the transmission120. Each of the one or more clutches may be selectively engageable in response to one or more fluid pressures applied thereto.

In the illustrative embodiment, the drive unit102is embodied as, or otherwise includes, any device capable of producing rotational power to drive other components (e.g., a torque converter108and the transmission120) of the drive system100in use thereof. In some embodiments, the drive unit102may be embodied as, or otherwise include, an internal combustion engine, diesel engine, electric motor, or other power-generating device. In any case, the drive unit102is configured to rotatably drive an output shaft104that is coupled to an input or pump shaft106of a torque converter108.

The input or pump shaft106of the illustrative torque converter108is coupled to an impeller or pump110that is rotatably driven by the output shaft104of the drive unit102. The torque converter108further includes a turbine112that is coupled to a turbine shaft114. In the illustrative embodiment, the turbine shaft114is coupled to, or integral with, the input shaft122of the transmission120.

The illustrative torque converter108also includes a lockup clutch136connected between the pump110and the turbine112of the torque converter108. The torque converter108is operable in a so-called “torque converter” mode during certain operating conditions, such as during vehicle launch, low speed conditions, and certain gear shifting conditions, for example. In the torque converter mode, the lockup clutch136is disengaged and the pump110rotates at the rotational speed of the drive unit output shaft104while the turbine112is rotatably actuated by the pump110through a fluid (not shown) interposed between the pump110and the turbine112. In this operational mode, torque multiplication occurs through the fluid coupling such that the turbine shaft114is exposed to more torque than is being supplied by the drive unit102. The torque converter108is alternatively operable in a so-called “lockup” mode during other operating conditions, such as when torque multiplication is not needed, for example. In the lockup mode, the lockup clutch136is engaged and the pump110is thereby secured directly to the turbine112so that the drive unit output shaft104is directly coupled to the input shaft124of the transmission118through the torque converter108.

In the illustrative embodiment, the transmission120includes an internal pump118configured to pressurize, and/or distribute fluid toward, one or more fluid (e.g., hydraulic fluid) circuits thereof. In some embodiments, the pump118may be configured to pressurize, and/or distribute fluid toward, a main circuit, a lube circuit, an electro-hydraulic control circuit, and/or any other circuit incorporated into the electro-hydraulic system138, for example. It should be appreciated that in some embodiments, the pump118may be driven by a shaft116that is coupled to the output shaft104of the drive unit102. In this arrangement, the drive unit102can deliver torque to the shaft116for driving the pump118and building pressure within the different circuits of the transmission120.

The illustrative transmission120includes a gearing system126coupled between the input shaft122and the output shaft124. It should be appreciated that the gearing system126may include one or more gear arrangements (e.g., planetary gear arrangements, epicyclic drive arrangements, etc.) that provide, or are otherwise associated with, one or more gear ratios. When used in combination with the one or more clutches and the electro-hydraulic system138under control by the control system2700, the gearing system126may provide, or otherwise be associated with, one or more operating ranges selectable by an operator.

The output shaft124of the transmission120is illustratively coupled to, or otherwise integral with, a propeller shaft128. The propeller shaft128is coupled to a universal joint130which is coupled to, and rotatably drives, the axle132and the wheels134A,134B. In this arrangement, the output shaft124drives the wheels134A,134B through the propeller shaft128, the universal joint130, and the axle132in use of the drive system100. Of course, it should be appreciated that, in other embodiments, the output shaft124may drive the wheels134A,134B through another suitable mechanism and/or collection of structures.

The illustrative transmission120includes the electro-hydraulic system138that is fluidly coupled to the gearing system126via a number (i.e., J) of fluid paths1401-1401, where J may be any positive integer. The electro-hydraulic system138is configured to receive control signals provided by various electro-hydraulic control devices (not shown), such as one or more sensors and one or more flow and/or pressure control devices, for example. In response to those control signals, and under control by the control system2700, the electro-hydraulic system138selectively causes fluid to flow through one or more of the fluid paths1401-1401to control operation (e.g., engagement and disengagement) of one or more friction devices (e.g., the one or more clutches) included in, or otherwise adapted for use with, the gearing system126.

Of course, it should be appreciated that the one or more friction devices may include, but are not limited to, one or more brake devices, one or more torque transmitting devices (i.e., clutches), and the like. Generally, the operation (e.g., engagement and disengagement) of the one or more friction devices is controlled by selectively controlling the friction applied by, or otherwise associated with, each of the one or more friction devices, such as by controlling fluid pressure applied to each of the friction devices, for example. In the illustrative embodiment, which is not intended to be limiting in any way, the electro-hydraulic system138may be coupled to, or otherwise adapted for use with, one or more brakes. Similar to the clutches, each of the one or more brakes may be controllably engaged and disengaged via fluid pressure supplied by the electro-hydraulic system138. In any case, changing or shifting between the various gears of the transmission120is accomplished by selectively controlling the friction devices via control of fluid pressure within the number of fluid paths1401-140J.

In the illustrative drive system100shown inFIG.1, the torque converter108and the transmission120include a number of sensors configured to produce sensor signals that are indicative of one or more operating states of the torque converter108and the transmission120, respectively. For example, the torque converter108illustratively includes a speed sensor146that is configured to produce a speed signal corresponding to the rotational speed of the pump shaft106, which rotates at the same speed as the output shaft104of the drive unit102in use of the drive system100. The speed sensor146is electrically connected to a pump speed input (i.e., PS) of the controller2702via a signal path152, and the controller2702is operable to process the speed signal produced by the speed sensor146to determine the rotational speed of the pump shaft106/drive unit output shaft104.

In the illustrative drive system100, the transmission120includes a speed sensor148that is configured to produce a speed signal corresponding to the rotational speed of the transmission input shaft122, which rotates at the same speed as the turbine shaft114of the torque converter108in use of the system100. The input shaft122of the transmission120may be directly coupled to, or otherwise integral with, the turbine shaft114. Of course, it should be appreciated that the speed sensor148may alternatively be configured to produce a speed signal corresponding to the rotational speed of the turbine shaft114. Regardless, the speed sensor148is electrically connected to a transmission input shaft speed input (i.e., TIS) of the controller2702via a signal path154, and the controller2702is operable to process the speed signal produced by the speed sensor148to determine the rotational speed of the turbine shaft114/transmission input shaft124.

Further, in the illustrative system100, the transmission120includes a speed sensor150that is configured to produce a speed signal corresponding to the rotational speed and direction of the output shaft124of the transmission120. The speed sensor150is electrically connected to a transmission output shaft speed input (i.e., TOS) of the controller2702via a signal path156. The controller2702is configured to process the speed signal produced by the speed sensor150to determine the rotational speed of the transmission output shaft124.

In some embodiments, the electro-hydraulic system138includes one or more actuators configured to control various operations within the transmission120. For example, the electro-hydraulic system138may include a number of actuators that are electrically connected to a number (i.e., J) of control outputs CP1-CPJof the controller2702via a corresponding number of signal paths721-72J, where J may be any positive integer as described above. Each of the actuators may receive a corresponding one of the control signals CP1-CPJproduced by the controller2702via one of the corresponding signal paths721-72J. In response thereto, each of the actuators may control the friction applied by each of the friction devices by controlling the pressure of fluid within one or more corresponding fluid passageway1401-140J, thereby controlling the operation of one or more corresponding friction devices based on information provided by the various speed sensors146,148, and/or150in use of the system100.

In the illustrative embodiment, the drive system100includes a drive unit controller160having an input/output port (I/O) that is electrically coupled to the drive unit102via a number (i.e., K) of signal paths162, wherein K may be any positive integer. The drive unit controller160is operable to control and manage the overall operation of the drive unit102. The drive unit controller160includes a communication port (i.e., COM) which is electrically connected to a similar communication port (i.e., COM) of the controller2702via a number (i.e., L) of signal paths164, wherein L may be any positive integer. It should be appreciated that the one or more signal paths164may be referred to collectively as a data link. Generally, the drive unit controller160and the transmission controller2702are operable to share information via the one or more signal paths164. In one embodiment, for example, the drive unit controller160and the transmission controller2702are operable to share information via the one or more signal paths164in the form of one or more messages in accordance with a Society of Automotive Engineers (SAE) J-1939 communications protocol. Of course, it should be appreciated that this disclosure contemplates other embodiments in which the drive unit controller160and the transmission controller2702are operable to share information via the one or more signal paths164in accordance with one or more other communication protocols (e.g., from a conventional databus such as J1587 data bus, J1939 data bus, IESCAN data bus, GMLAN, Mercedes PT-CAN).

Referring again toFIG.2, the electro-hydraulic valve assembly220is contained in a case extension204of the transmission120as further discussed below. Multiple structures of the actuation linkage230(e.g., the plate240, the biasing element250, the sleeve1260, and a bushing280) are mounted on a selector shaft212that extends through the main case202of the transmission120and into an interior space214defined by the main case202. As described below with reference toFIG.19, rotation of the selector shaft212may be driven by operation of the parking lock mechanism1900in the event of a hydraulic failure or fault condition.

In the illustrative embodiment, the actuation linkage230includes the bushing280which is supported by the shaft212on the rotational axis RA between the plate240and the interior wall1204of the main case202. The bushing280includes, or is otherwise embodied as, any structure or collection of structures capable of supporting the plate240for rotation about the rotational axis RA. In some embodiments, the bushing280may include, or otherwise be embodied as, a plain bearing, a sleeve bushing, a split bushing, a clenched bushing, or the like. In any case, at least in some embodiments, the bushing280is configured to support the plate240for rotation about the rotational axis RA relative to the shaft212. Additionally, in some embodiments, the bushing280is configured to support the plate240for rotation about the rotational axis RA with the shaft212.

Referring now toFIG.3, in the illustrative embodiment, the park system200includes the park pawl312, a plurality of rollers314, and a ramp (not shown). The park pawl312is illustratively movable to directly contact the structure/gear of the park assembly200(e.g., in the engaged state1300of the park assembly210) and to be spaced from, and not in direct contact with, the structure/gear (e.g., in the disengaged state1500of the park assembly210). The rollers314are movable along the ramp (e.g., in one direction) to interact with the park pawl312and thereby cause contact between the park pawl312and the structure/gear. The rollers314are also movable along the ramp (e.g., in another direction opposite the one direction) to cause the park pawl312to be spaced from the structure/gear. The rollers314are coupled together for common movement along and/or parallel to the ramp by a carriage or carrier316.

The park system200illustratively includes a position sensor360to generate a signal indicative of a position of the plate240about the rotational axis RA. More specifically, as best seen inFIG.11, the position sensor360is mounted to the main case202of the transmission120and configured to detect a position of one or more notches1140formed in the plate240about the rotational axis RA. In some embodiments, the sensor360includes, or is otherwise embodied as, any electrical device or collection of electrical devices capable of detecting a position of the plate240about the rotational axis RA in use of the park system200. Additionally, in some embodiments, the sensor360includes, or is otherwise embodied as, a proximity sensor, such as a capacitive proximity sensor, an inductive proximity sensor, a hall effect sensor, or the like. Of course, in other embodiments, the sensor360may include, or otherwise be embodied as, another suitable sensor.

The park system200illustratively includes a locking pin370to selectively block translation of the piston270along the longitudinal axis LA and thereby secure the position of the piston270along the axis LA in use of the system200. In the illustrative embodiment, the locking pin370includes, or is otherwise embodied as, a solenoid-driven locking pin sized for positioning in one of several grooves formed in the piston270, as further discussed below. In other embodiments, the locking pin370may include, or otherwise be embodied as, another suitable device.

Referring now toFIGS.4and5, in at least some embodiments, the main case202includes, or is otherwise embodied as, a main body404and a secondary body406coupled to the main body404. The secondary body406may include, or otherwise define, an oil pan as discussed below with reference toFIG.26. The main body404illustratively extends circumferentially all the way around a central axis504. In some embodiments, the main body404is configured to at least partially house various components of the transmission120, such as one or more clutches, one or more elements of the gearing system126, and/or one or more elements of the electro-hydraulic system138, for example. As best seen inFIG.5, the main body404is formed to include a cylindrical cavity506that extends therethrough. In some embodiments, the cavity506may be sized to receive the output shaft124of the transmission120therein.

In some embodiments, when the main body404and the secondary body406are coupled to one another, at least some structures of the park system200are disposed in an interior space508defined by the secondary body406. More specifically, as best seen inFIG.5, the case extension204is illustratively sized to be positioned in the interior space508when the main body404and the secondary body406are coupled to one another. As such, at least in some embodiments, the secondary body406may provide an external enclosure that covers and protects the case extension204and any structures contained therein, such as the electro-hydraulic valve824and the piston270, for instance.

In the illustrative embodiment, the case extension204is located outward of the cylindrical cavity506in a radial direction indicated by arrow R. The arrangement of the electro-hydraulic valve824and the piston270in the case extension204is indicated inFIG.4with those components shown in phantom. When housed by the case extension204, the piston270is disposed in closer proximity to one end410of the case extension204than another end412of the case extension204arranged opposite the one end410. The electro-hydraulic valve824is disposed in closer proximity to the end412than the end410.

Referring now toFIGS.6and7, a solenoid626of the electro-hydraulic valve220is disposed at or in close proximity to the end412of the case extension204. In the illustrative embodiment, the solenoid626is embodied as, or otherwise includes, any device or collection of devices (e.g., electromagnets) capable of producing a controlled magnetic field through which electric current may be passed in use of the electro-hydraulic valve assembly220. In some embodiments, the solenoid626may be embodied as, or otherwise include, one or more transducer(s) or the like capable of converting electrical energy into linear motion to actuate one or more components of the electro-hydraulic valve assembly220, such as the electro-hydraulic valve824, for example.

In the illustrative embodiment, the case extension204defines an internal cavity606(shown in phantom) located in close proximity to the end410thereof in which the piston270is positioned. As best seen inFIGS.14and16, the piston270is axially translatable along the longitudinal axis LA in the internal cavity606in response to one or more fluid pressures delivered thereto from the electro-hydraulic valve assembly220. The internal cavity606is sized to accommodate a head1372(seeFIG.13) of the piston270and a piston shaft1374of the piston270as described in greater detail below.

The illustrative locking pin370includes a cover672that is coupled to the case extension204and extends outwardly therefrom as best seen inFIG.6. Although the case extension204and the cover672are illustratively formed as separate structures, it should be appreciated that in some embodiments, the case extension204and the cover672may be integrally formed with one another. In any case, the cover672is sized to house a solenoid674of the locking pin370that is configured to drive extension of the locking pin370into the internal cavity606and retraction of the locking pin370outside of the internal cavity606, as best seen inFIGS.14and16.

In some embodiments, a separator plate708(shown in phantom) may be disposed in the case extension204proximate the end412thereof. In some configurations, the separator plate708may be utilized in conjunction with the case extension204to establish one or more passages or fluid paths for conducting hydraulic fluid from the electro-hydraulic valve assembly220to the piston270. In such cases, the separator plate708may define, form a portion of, or otherwise be included in, a fluid distribution circuit710at least partially disposed in the case extension204.

Referring now toFIG.8, in the illustrative embodiment, the electro-hydraulic valve assembly220includes the electro-hydraulic valve824, the solenoid626, and a clip. In at least some configurations, the solenoid626is received by, and retained by the clip in contact with, a valve body of the electro-hydraulic valve824defined by the case extension204when the electro-hydraulic valve assembly220is assembled. The spool822is disposed in the valve body and configured for axial movement along a valve body axis VBA in response to one of more fluid pressures applied to the spool822by the solenoid626. A biasing element or spring832disposed in a return chamber834applies a biasing force (not shown) to the spool822to resist axial movement of the spool822along the valve body axis VBA toward the return chamber834in use of the electro-hydraulic valve assembly220.

In the illustrative embodiment, the valve element or spool822includes a plurality of discrete sections or lands. The spool822illustratively includes two lands834A,834B. Of course, in another embodiments, it should be appreciated that the spool822may include another suitable number of lands, such as more than two lands, for example. The lands834A,834B may each have the same diameter, at least in some cases. In other cases, the lands may have different diameters. In any case, the spool822cooperates with the case extension204to define one or more fluid chambers of the electro-hydraulic valve824that are configured to receive fluid (e.g., hydraulic fluid).

At least one fluid chamber of the electro-hydraulic valve824is fluidly coupled to the internal cavity606of the case extension204. In some embodiments, the at least one fluid chamber may be fluidly coupled to the internal cavity606by one or more fluid passages or conduits defined within, and enclosed by, the case extension204. Regardless, the at least one fluid chamber is in fluid communication with an actuation cavity840defined between an inner shoulder804of the case extension204and the piston270. As further discussed below, one or more fluid pressures may be delivered to the actuation cavity840from the at least one chamber of the electro-hydraulic valve824to drive movement of the piston270along the longitudinal axis LA.

Referring now toFIGS.9and10, in the illustrative embodiment, a fluid chamber924of the electro-hydraulic valve824defined between the spool822and the case extension204is fluidly coupled to the actuation cavity840. A fluid flow path900is established between the fluid chamber924of the electro-hydraulic valve824and the actuation cavity840as illustrated inFIG.9. A fluid flow path1000is established between the fluid chamber924of the electro-hydraulic valve824and the actuation cavity840as illustrated inFIG.10.

The fluid flow path900corresponds to, and contributes to the establishment of, the engaged state1300of the park assembly210. The fluid flow path1000corresponds to, and contributes to the establishment of, the disengaged state1500of the park assembly210. It should be appreciated that each of the fluid flow paths900,1000may be at least partially defined through the case extension204, at least in some embodiments.

In the illustrative embodiment, in the engaged state1300of the park assembly210, the electro-hydraulic valve824delivers a pressure P1from the fluid chamber924to the actuation cavity840along the flow path900as shown inFIG.9. At least in some embodiments, the pressure P1corresponds to, or is otherwise embodied as, an exhaust backfill (EBF) pressure having a magnitude that is insufficient to drive axial translation of the piston270along the longitudinal axis LA. In the engaged state1300of the park assembly210, the solenoid626applies minimal or substantially no fluid pressure to the spool822of the electro-hydraulic valve824. Consequently, the solenoid626is positioned in close proximity to, and/or in contact with, the spool822in the engaged state1300of the park assembly210as shown inFIG.9.

In the illustrative embodiment, in the disengaged state1500of the park assembly210, the electro-hydraulic valve824delivers a pressure P2from the fluid chamber924to the actuation cavity840along the flow path1000as shown inFIG.10. At least in some embodiments, the pressure P2corresponds to, or is otherwise embodied as, a pressure having a magnitude greater than the pressure P1which is sufficient to drive axial translation of the piston270along the longitudinal axis LA. In the disengaged state1500of the park assembly210, the solenoid626applies appreciable fluid pressure to the spool822of the electro-hydraulic valve824such that the spool822is spaced from the solenoid626along the valve body axis VBA as shown inFIG.10.

Referring now toFIG.11, the plate240is illustratively arranged in the main case202in close proximity to the position sensor360. The position sensor360is affixed to the main case202(e.g., mounted to the main body404and/or the secondary body406) and configured to detect a position of one or more of the notches1140formed in the plate240about the rotational axis RA as indicated above. The plate240is at least partially supported for rotation about the rotational axis RA by the bushing280which is arranged between the plate240and the inner wall1204of the main case202of the transmission120.

In the illustrative embodiment, the plate240includes a body1150that surrounds the rotational axis RA. The body1150has an indexing flange1160appended thereto that extends outwardly away from the body1150in a direction indicated by arrow D1. At an outer periphery1162thereof, the indexing flange1160is formed to include fingers1164defining the notches1140therebetween. The indexing flange1160illustratively includes six fingers1164that define five notches1140therebetween. Of course, it should be appreciated that in other embodiments, the indexing flange1160may include another suitable number of fingers1164and corresponding notches1140.

In the illustrative embodiment, the notches1140are circumferentially spaced from one another around the indexing flange1160of the body240. Each notch1140is indicative of a particular angular orientation of the plate240about the rotational axis RA in use of the park system200. As such, based on the detection of one or more notches1140by the position sensor360, a determination may be made (e.g., by the controller2702) as to the angular orientation of the plate240and a corresponding operational state (i.e., the engaged state1300or the disengaged state1500) of the park assembly210.

It should be appreciated that throughout operation of the illustrative park system200, no features are positioned in the notches1140. In one example, as best seen inFIG.13, no features are positioned in the notches1140during operation of the park assembly210in the engaged state1300. In another example, as best seen inFIG.15, no features are positioned in the notches1140during operation of the park assembly210in the disengaged state1500.

The illustrative body1150of the plate240also includes a mount extension1170appended to the body1150that extends outwardly away from the body1150in a direction indicated by arrow D2. The direction D2is illustratively different from the direction D1. In some cases, the direction D2may be perpendicular or substantially perpendicular to the direction D1. Additionally, in some cases, the mount extension1170and the indexing flange1160may be circumferentially spaced 90 degrees, or at least 90 degrees, from one another around the rotational axis RA. In any case, the mount extension1170is pivotally coupled to a rod1130of the actuation linkage230that, as discussed below, is adapted for linear translation along a longitudinal axis LA′ spaced from the longitudinal axis LA in use of the park system200.

The illustrative body1150of the plate240also includes a mount extension1180appended to the body1150that extends outwardly away from the body1150in a direction indicated by arrow D3. The direction D3is illustratively different from the directions D1and D2. In some cases, the direction D3may be perpendicular or substantially perpendicular to each of the directions D1and D2. Additionally, in some cases, the mount extension1180and the indexing flange1160may be circumferentially spaced 90 degrees, or at least 90 degrees, from one another around the rotational axis RA. In some cases still, the mount extension1180and the mount extension1170may be circumferentially spaced 180 degrees, or at least 180 degrees, from one another around the rotational axis RA. In any case, the mount extension1180is pivotally coupled to the piston270at least partially housed in the case extension204, as further discussed below.

In the illustrative embodiment, the indexing flange1160, the mount extension1170, and the mount extension1180define separate structures and/or sections of the plate240that are spaced from one another and appended to the body1150. The illustrative plate240includes an arcuate section1166that interconnects the body1150and the mount extension1170and an arcuate section1176that interconnects the body1150and the mount extension1180. The arcuate section1166defines at least one bend1168between the body1150and the mount extension1170, whereas the arcuate section1176defines at least one bend1178between the body150and the mount extension1180. In some embodiments, the arcuate sections1166,1176are similar or identical structures of the plate240that are arranged opposite one another. Additionally, in some embodiments, each of the arcuate sections1166,1176includes, or is otherwise embodied as, a stiffening tab, rib, spine, or similar structure, as the case may be.

As best seen inFIG.11, the bushing280is illustratively formed to include a pair of slots1182extending therethrough that are circumferentially spaced 180 degrees from one another about the rotational axis RA. The slots1182may at least partially define halves1184,1186of the bushing280that are interconnected with one another, at least in some embodiments. Further, in some embodiments, the halves1184,1186may include respective projections1188,1190. The slots1182may permit some degree of flexion and/or resiliency of the bushing280when the bushing280is mounted on the shaft212. The projections1188,1190may stiffen and/or reinforce the bushing280to offset a lack of stiffness imparted by the slots1182. Additionally, the projections1188,1190may limit axial movement of the bushing280relative to the plate240along the rotational axis RA.

Referring now toFIG.12, the biasing element250illustratively includes, or is otherwise embodied as, a torsional spring1250. Of course, in other embodiments, the biasing element250may include, or otherwise be embodied as, another suitable structure. Regardless, the biasing element250is wound around the sleeve1260and at least partially retained around the rotational axis RA by the sleeve1260as indicated above. As discussed below, the biasing element250is coupled to the plate240and thereby at least partially retained around the rotational axis RA by the plate240.

The arcuate section1176of the plate240is illustratively formed to include a mount aperture1278that is sized to receive a mount tang1252of the biasing element250. When the mount tang1252extends through the mount aperture1278as shown inFIG.12, the biasing element250is at least partially retained in place by the plate240. In at least some embodiments, the mount aperture1278extends through the arcuate section1176in the direction D3, and the direction D3is perpendicular or substantially perpendicular to the rotational axis RA.

In the illustrative embodiment, the mount tang1252includes portions1254,1256that are interconnected with one another by a bend1258. When the mount tang1252is received by the mount aperture1278as shown inFIG.12, the portion1254extends through the mount aperture1278in the direction D3. Additionally, when the mount tang1252is received by the mount aperture1278, the portion1256is arranged outside of the mount aperture1278at an angle R to the portion1254. In some embodiments, the angle R is 90 degrees or about 90 degrees. In other embodiments, the angle R is less than 90 degrees.

The sleeve1260illustratively includes, or is otherwise embodied as, a cylindrical structure1262(e.g., a ring, a washer, or the like) supported by the shaft212and mounted on the rotational axis RA. The plate240of the actuation linkage230is arranged along the rotational axis RA at least partially between the sleeve1260and the bushing280. Consequently, at least in some embodiments, the sleeve1260and the bushing280cooperate to at least partially locate the plate240along the rotational axis RA. Additionally, in some embodiments, the biasing element250is wound around the sleeve1260such that the sleeve1260, the bushing280, and the biasing element250cooperate to at least partially locate the plate240along the rotational axis RA.

In the illustrative embodiment, the sleeve1260is configured for linear movement along the rotational axis RA in use of the park system200as indicated above. Such linear movement may include, or otherwise be embodied as, axial float of the sleeve1260along the rotational axis RA over a short or relatively short distance toward or away from the bushing280. In some embodiments, the sleeve1260is configured for linear translation along the rotational axis RA such that the sleeve1260contacts the bushing280. In such embodiments, contact between the sleeve1260and the bushing280may limit axial float of the sleeve1260along the rotational axis RA.

The rod1130is illustratively coupled to the mount extension1170of the plate240by a collar or collar assembly1270as shown inFIG.12. The collar1270includes a mount block1272and a coupling pin1274that protrudes outwardly away from the mount block1272toward the interior wall1204of the main case202. In some embodiments, the mount block1272and the coupling pin1274may be provided as separate structures affixed to one another. In other embodiments, the mount block1272and the coupling pin1274may be integrally formed as a single unitary structure. Regardless, in the illustrative embodiment, the coupling pin1274extends through the mount extension1170and the rod1130extends through the mount block1272to establish a pivotal coupling between the plate240and the rod1130.

In some embodiments, the collar1270receives the rod1130to permit translation of the rod1130along the longitudinal axis LA′ in response to movement of the piston270along the longitudinal axis LA. Additionally, in some embodiments, the coupling between the rod1130and the mount extension1170via the collar1270permits a degree of relative movement between the rod1130and the plate240in use of the park system200. In one example, the collar1270permits some amount of movement of the rod1130relative to the mount extension1170along the longitudinal axis LA′. In some cases, the collar1270may permit a minimal amount of linear movement of the rod1130relative to the mount extension1170along the axis LA′, such as zero or substantially zero linear movement, for instance. In another example, the collar1270permits some amount of rotational movement of the rod1130relative to the mount extension1170. In some cases, the collar1270may permit a minimal amount of rotational movement of the rod1130relative to the mount extension1170, such as zero or substantially zero rotational movement between the rod1130and the body mount extension1170, for instance.

Referring now toFIGS.13and14, in the illustrative embodiment, an end1332of the rod1130is coupled to, or integrally formed with, the carriage316which carries the rollers314as indicated above. In some embodiments, the end1332of the rod1130may be configured for direct interaction with the rollers314. Although the rod1130is described herein as a component of the actuation linkage230, the rod1130may be incorporated into the park assembly210and considered as a component of the park assembly210, at least in some embodiments. In any case, the rod1130illustratively supports, and is at least partially surrounded by, a biasing element or spring1340such that the biasing element1340extends along the longitudinal axis LA′ between the rollers314and the mount extension1170of the plate240.

In the illustrative engaged state1300of the park assembly210, the electro-hydraulic valve assembly220(e.g., the electro-hydraulic valve824) delivers the pressure P1to the actuation cavity840which has a magnitude insufficient to drive axial translation of the piston270along the longitudinal axis LA as indicated above. As such, in the illustrative state1300, interaction between the mount extension1180and the piston270does not drive substantial or appreciable rotation of the plate240about the rotational axis RA. The biasing element250applies the biasing force BF to the plate240to urge interaction between the mount extension1180and the piston270in the engaged state1300. The position sensor360detects one or more of the notches1140which provide an indication of the angular orientation of the plate240about the rotational axis RA in the engaged state1300of the park assembly210.

Due to the magnitude of the pressure P1and the corresponding application of zero or minimal fluid pressure to the actuation cavity840, the head1372of the piston270illustratively abuts the inner shoulder804of the case extension204when the park assembly210is in the engaged state1300. As a result, the head1372is spaced from a retaining ring1380located within the internal cavity606of the case extension204in the engaged state1300of the park assembly210. In the engaged state1300of the park assembly210, the piston shaft1374of the piston270is disposed in a bore1382that has a smaller diameter than the actuation cavity840.

In the illustrative embodiment, as shown inFIGS.14and16, the piston shaft1374of the piston270is formed to include grooves1472,1674at an outer periphery1476thereof. In some embodiments, the grooves1472,1674each have a conical cross-sectional shape. However, in other embodiments, the grooves1472,1674may take the shape of other suitable geometric forms. Regardless, the grooves1472,1674are spaced from one another in a direction indicated by arrow D4that is parallel to the longitudinal axis LA.

As suggested above, in the illustrative embodiment, the locking pin370is sized for positioning in the groove1472or in the groove1674to block translation of the piston270along the longitudinal axis LA and thereby secure the piston270in place. When the park assembly210is in the engaged state1300, the locking pin370extends into the internal cavity606such that the locking pin370is positioned in the groove1472. The extended state of the locking pin370into the groove1472may correspond to, or otherwise be associated with, an energized or activated state of the locking pin370.

Referring now toFIGS.15and16, in the illustrative disengaged state1500of the park assembly210, the electro-hydraulic valve assembly220(e.g., the electro-hydraulic valve824) delivers the pressure P2to the actuation cavity840which has a magnitude sufficient to drive axial translation of the piston270along the longitudinal axis LA as indicated above. As such, in the illustrative state1500, interaction between the mount extension1180and the piston270drives appreciable rotation of the plate240about the rotational axis RA as the piston270translates along the longitudinal axis LA. The biasing element250applies the biasing force BF to the plate240to urge interaction between the mount extension1180and the piston270in the disengaged state1500. The position sensor360detects one or more of the notches1140which provide an indication of the angular orientation of the plate240about the rotational axis RA in the disengaged state1500of the park assembly210. It should be appreciated that in at least some embodiments, the one or more notches1140that may be detected by the position sensor360to indicate the disengaged state1500of the park assembly210are different from the one or more notches1140that may be detected by the position sensor360to indicate the engaged state1300of the park assembly210.

Due to the magnitude of the pressure P2and the corresponding application of appreciable fluid pressure to the actuation cavity840, the head1372of the piston270is spaced from the inner shoulder804of the case extension204when the park assembly210is in the disengaged state1500. The head1372illustratively abuts the retaining ring1380in the disengaged state1500of the park assembly210. In the disengaged state1500of the park assembly210, the piston shaft1374of the piston270is at least partially disposed in the bore1382and in the actuation cavity840.

When the park assembly210is in the disengaged state1500, the locking pin370extends into the internal cavity606such that the locking pin370is positioned in the groove1674. The extended state of the locking pin370into the groove1674may correspond to, or otherwise be associated with, an energized or activated state of the locking pin370during the disengaged state1500of the park assembly210.

Referring now toFIGS.17and18, in the illustrative embodiment, the head1372of the piston270illustratively includes, or otherwise defines, an orientation indication bar1774. In at least some embodiments, the orientation indication bar1774provides an indication of an installation orientation of the piston270in the case extension204. As best seen inFIG.17, when the piston270is installed in the case extension204and the secondary body406is removed, the orientation indication bar1774is observable from an exterior of the case extension204. Thus, in some embodiments, at least partially based on the installation orientation indicated by the orientation indication bar1774, a user may determine whether the piston270is installed in the case extension204in the proper orientation.

In the illustrative embodiment, the case extension204is formed to include an anti-rotation pin1806that is configured to resist rotation of the piston270(e.g., about the longitudinal axis LA) relative to the case extension204when the piston270is properly installed in the case extension204. In some embodiments, the anti-rotation pin1806is configured for interaction (e.g., direct contact and/or interference) with the piston shaft1374of the piston270. Additionally, in some embodiments, interaction between the anti-rotation pin1806and the piston270that resists rotation of the piston270relative to the case extension204may be indicative of installation of the piston270in the case extension204in the proper orientation. In those embodiments, rotational resistance effected by the anti-rotation pin1806may be observed in combination with the orientation indicated by the orientation indication bar1774to determine whether the piston270is installed in the case extension204in the proper orientation.

In the illustrative embodiment, as best seen inFIG.18, the piston shaft1374of the piston270is formed to include a post1876that is configured for interaction with the mount extension1180of the plate240. More specifically, the post1876is configured to directly contact a tab1882of the mount extension1180throughout operation of the park system200. In at least some embodiments, the biasing force BF applied to the plate240by the biasing element250urges interaction between the post1876and the tab1882of the mount extension1180in each of the engaged and disengaged states1300,1500of the park assembly210.

Referring now toFIG.19, the illustrative parking lock mechanism1900includes a lever1910, a coupling nut1920, and a fastener1930. One end1912of the lever1910is pivotally coupled to the shaft212by the coupling nut1920, and another end1914of the lever1910arranged opposite the one end1912is adapted for securement to the main case202of the transmission102using the fastener1930. The illustrative positioning of the lever1910inFIG.19corresponds to, or is otherwise associated with, a disengaged or de-activated state1940of the parking lock mechanism1900in which a user has not manually manipulated the lever1910and the shaft212to place the park system200in a neutral operating mode. In the disengaged state1940of the parking lock mechanism1900, hydraulic fluid is selectively delivered to the piston270to drive normal operation of the park assembly210in the engaged and disengaged states1300,1500.

In the illustrative embodiment, the parking lock mechanism1900is not installed on the transmission120during normal operation thereof. Rather, in the event of a failure or fault that prevents fluid from being delivered to the piston270during normal operation, the parking lock mechanism1900may be installed (e.g., by the vehicle operator) on the transmission120and manually manipulated to place the park system200in the disengaged state1500. More specifically, in the event of a failure or fault, a user attaches the end1912of the lever1910to the shaft212and secures the end1912to the shaft212using the coupling nut1920. Then, the user rotates the lever1910relative to the main case202to a neutral operating position1950depicted inFIG.19. It should be appreciated that rotation of the lever1910to the neutral operating position1950drives rotation of the shaft212to place the park system200in the disengaged state1500. After the lever1910is rotated to the neutral operating position1950and an aperture (not shown) formed in the lever1910adjacent the end1914is aligned with a corresponding aperture (not shown) formed in the main case202, the user may secure the lever1910to the main case202by inserting the fastener1930through the apertures formed in the lever1910and the main case202.

Referring now toFIG.20, the selector shaft212illustratively includes a shaft body2014having a generally cylindrical shape and at least one flat or planar section2016formed in the body2014. The flat section2016is formed to include holes2018,2020extending through the shaft212. Compared to other configurations, the flat section2016may include a greater number of holes. Additionally, compared to other configurations, the flat section2016may have a longer length L.

Referring now toFIG.21, a fluid distribution manifold2100for an electro-hydraulic circuit includes a network of features2110in fluid communication with one another to route hydraulic fluid to various structures and/or devices of a hydraulic system. The features2110include, but are not limited to, fluid passages, fluid ports, fluid paths, and the like.

Referring now toFIG.22, a fluid distribution manifold2200for an electro-hydraulic circuit is adapted for use with the park system200. The manifold2200illustratively includes a network of features2210in fluid communication with one another to route hydraulic fluid to various structures and/or devices of a hydraulic system, such as the hydraulic system2750(seeFIG.27), for example. The features2210include, but are not limited to, fluid passages, fluid ports, fluid paths, and the like. At least in some embodiments, the fluid paths established by the features2210may be different from the fluid paths established by the features2110.

Referring now toFIG.23, in at least some embodiments, a primary body2310and an auxiliary body2320cooperatively establish the fluid distribution manifold2200. The primary body2310and the auxiliary body2320are in fluid communication with one another to cooperatively route fluid to various structures and/or devices of the park system200, including the electro-hydraulic valve824and the piston270. In one aspect, the features2210include a fluid port and/or passage2330through which the pressure P1(e.g., the exhaust backfill pressure) may be routed to the actuation cavity840through the electro-hydraulic valve824. In another respect, the features2210include a fluid port and/or passage2340through which the pressure P2may be routed to the actuation cavity840through the electro-hydraulic valve824. In yet another respect, the features2210include a fluid passage2350that fluidly couples the electro-hydraulic valve824to the actuation cavity840.

Referring now toFIGS.24and25, in the illustrative embodiment, the main case202of the transmission120includes features2400formed on an exterior2402of the case202. In some embodiments, the features2400formed on the exterior2402of the case202may be complemented by features2500formed on an interior2502of the case202. The features2400,2500may cooperate to route fluid through the main case202to various structures and/or devices of the park system200, at least in some embodiments. The features2400,2500may be omitted from other configurations.

Referring now toFIG.26, in the illustrative embodiment, the main case202(e.g., the secondary body406) includes an oil pan2600having a drain plug2602. The oil pan2600is illustratively adapted for use with the park system200. Compared to other configurations, the drain plug2602may be repositioned to facilitate use with the park system200.

Referring now toFIG.27, in the illustrative embodiment, the control system2700includes the hydraulic system2750, the selector shaft212, the position sensor360, the locking pin370, the controller2702, input devices2710, and other device(s)2720. Each of the systems and/or devices2750,212,360,370,2710, and2720is communicatively coupled to the controller2702, such as by a direct (e.g., hardwired) connection or a controller area network (CAN) interface, for example. Of course, it should be appreciated that the control system2700may include other electrical and/or electro-mechanical devices in addition to, or as an alternative to, the devices depicted inFIG.27. In any case, the illustrative controller2702includes a processor2704(or one or more processors) and at least one memory device2706communicatively coupled to the processor2704.

The processor2704of the illustrative controller2702may be embodied as, or otherwise include, any type of processor, controller, or other compute circuit capable of performing various tasks such as compute functions and/or controlling the functions of the transmission120and/or the park system200, for example. For example, the processor2704may be embodied as a single or multi-core processor(s), a microcontroller, or other processor or processing/controlling circuit. In some embodiments, the processor2704may be embodied as, include, or otherwise be coupled to an FPGA, an application specific integrated circuit (ASIC), reconfigurable hardware or hardware circuitry, or other specialized hardware to facilitate performance of the functions described herein. Additionally, in some embodiments, the processor2704may be embodied as, or otherwise include, a high-power processor, an accelerator co-processor, or a storage controller. In some embodiments still, the processor2704may include more than one processor, controller, or compute circuit.

The memory device2706of the illustrative controller2702may be embodied as any type of volatile (e.g., dynamic random access memory (DRAM), etc.) or non-volatile memory capable of storing data therein. Volatile memory may be embodied as a storage medium that requires power to maintain the state of data stored by the medium. Non-limiting examples of volatile memory may include various types of random access memory (RAM), such as dynamic random access memory (DRAM) or static random access memory (SRAM). One particular type of DRAM that may be used in a memory module is synchronous dynamic random access memory (SDRAM). In particular embodiments, DRAM of a memory component may comply with a standard promulgated by JEDEC, such as JESD79F for DDR SDRAM, JESD79-2F for DDR2 SDRAM, JESD79-3F for DDR3 SDRAM, JESD79-4A for DDR4 SDRAM, JESD209 for Low Power DDR (LPDDR), JESD209-2 for LPDDR2, JESD209-3 for LPDDR3, and JESD209-4 for LPDDR4 (these standards are available at www.jedec.org). Such standards (and similar standards) may be referred to as DDR-based standards and communication interfaces of the storage devices that implement such standards may be referred to as DDR-based interfaces.

In some embodiments, the memory device2706may be embodied as a block addressable memory, such as those based on NAND or NOR technologies. The memory device2706may also include future generation nonvolatile devices, such as a three dimensional crosspoint memory device (e.g., Intel 3D XPoint™ memory), or other byte addressable write-in-place nonvolatile memory devices. In some embodiments, the memory device2706may be embodied as, or may otherwise include, chalcogenide glass, multi-threshold level NAND flash memory, NOR flash memory, single or multi-level Phase Change Memory (PCM), a resistive memory, nanowire memory, ferroelectric transistor random access memory (FeTRAM), anti-ferroelectric memory, magnetoresistive random access memory (MRAM) memory that incorporates memristor technology, resistive memory including the metal oxide base, the oxygen vacancy base and the conductive bridge Random Access Memory (CB-RAM), or spin transfer torque (STT)-MRAM, a spintronic magnetic junction memory based device, a magnetic tunneling junction (MTJ) based device, a DW (Domain Wall) and SOT (Spin Orbit Transfer) based device, a thyristor based memory device, or a combination of any of the above, or other memory. The memory device may refer to the die itself and/or to a packaged memory product. In some embodiments, 3D crosspoint memory (e.g., Intel 3D XPoint™ memory) may comprise a transistor-less stackable cross point architecture in which memory cells sit at the intersection of word lines and bit lines and are individually addressable and in which bit storage is based on a change in bulk resistance.

The illustrative hydraulic system2750includes the solenoid or pressure control solenoid (PCS)626which is communicatively coupled to the controller2702. In the illustrative embodiment, the solenoid626includes, or is otherwise embodied as, any variable-force solenoid or collection of variable-force solenoids configured to receive input (e.g., one or more control signals) from the controller2702and supply variable hydraulic fluid pressure to the electro-hydraulic valve824in response to the input provided by the controller2702. As evident from the discussion above, the solenoid626is configured to direct delivery of the fluid pressure P2through the electro-hydraulic valve824to the actuation cavity840in the disengaged state1500of the park assembly210. In some embodiments, the hydraulic fluid pressure P2may correspond to a trim pressure regulated by a main regulator valve (not shown) of the hydraulic system2750.

The illustrative hydraulic system2750also includes the electro-hydraulic or actuator valve824which is communicatively coupled to the controller2702. As evident from the discussion above, the electro-hydraulic valve824includes, or is otherwise embodied as, a hydraulic actuator valve configured to convert fluid pressure into linear motion (e.g., of the valve element822) to drive operation of the park system200. In the illustrative embodiment, the electro-hydraulic valve824is fluidly coupled to the solenoid626as indicated above.

Although not shown, in some embodiments, the hydraulic system2750may include a number of devices in addition to those depicted inFIG.27. Those devices may include, but are not limited to, one or more trim systems, sensors, controllers, pressure control solenoids, solenoid valves, relay valves, regulator valves, and flow control devices. The additional device(s) may be communicatively coupled to the controller2702to receive input (e.g., one or more control signals) therefrom and/or provide input thereto.

The selector shaft212illustratively includes, or is otherwise embodied as, a shift-by-cable selector shaft configured for movement (i.e., rotation) in response to an input (e.g., an operator input) received by the controller2702. In some embodiments, in response to input provided by one of the input devices2710, the controller2702is operable to direct rotation of the selector shaft212via one or more electrically-powered devices, such as one or more electric motors, electric actuators, or the like.

As indicated above, the position sensor360illustratively includes, or is otherwise embodied as, any electrical device or collection of electrical devices capable of generating a signal indicative of a position of one or more notches1140of the plate240about the rotational axis RA. The illustrative position sensor360includes a hall-effect sensor. Of course, in other embodiments, the sensor360may include another suitable device.

As mentioned above, the locking pin370illustratively includes, or is otherwise embodied as, a solenoid-driven locking pin sized for positioning in one of the grooves1472,1674formed in the shaft1374of the piston270. The locking pin (not shown) is configured to extend (e.g., when active or deployed) into, or retract (e.g., when inactive or stowed) outside of, the grooves1472,1674.

In the illustrative embodiment, the input devices2710include a park input2712and a non-park input2714. Each of the inputs2712and2714is communicatively coupled to the controller2702, at least in some embodiments. The park input2712includes, or is otherwise embodied as, an input device that may be selected by a user to direct operation of the transmission120and the park system200in a park operating mode corresponding to the engaged state1300. The non-park input2714includes, or is otherwise embodied as, an input device that may be selected by a user to direct operation of the transmission120and the park system200in a non-park operation mode (e.g., a neutral or drive mode) corresponding to the disengaged state1500.

In some embodiments, the other device(s)2720include one or more other electrical or electro-mechanical devices included in the park system200, the transmission120, and/or the drive system100. The device(s)2720may be incorporated into, or otherwise associated with, the drive unit102, the torque converter108, the transmission120, the gearing system126, or the electro-hydraulic system138, as the case may be. For example, the device(s)2720may include the speed sensors146,148,150, at least in some embodiments. In another example, the device(s)2720may include the controller160. Additionally, in some embodiments, the device(s)2720may include one or more sensors, controllers, solenoids, solenoid valves, and flow control devices, among other things.

Referring now toFIG.28, an illustrative method2800of operating the transmission120may be embodied as, or otherwise include, a set of instructions that are executable by the control system2700. The method2800corresponds to, or is otherwise associated with, performance of the blocks described below in the illustrative sequence ofFIG.28. It should be appreciated, however, that the method2800may be performed in one or more sequences different from the illustrative sequence.

The illustrative method2800begins with block2802. In block2802, the controller2702operates the transmission120and the park system200in the engaged state1300. As a result, in block2802, the controller2702resists rotation of the output shaft124using the park assembly210of the system200. In the illustrative embodiment, to perform block2802, the controller2702performs the method2900described below with reference toFIG.29. From block2802, the method2800proceeds to block2804.

In block2804of the illustrative method2800, the controller2702operates the transmission120and the park system200in the disengaged state1500. Consequently, in block2804, the controller2702allows rotation of the output shaft124using the park assembly210of the system200. In the illustrative embodiment, to perform block2804, the controller702performs the method3000described below with reference toFIG.30.

Referring now toFIG.29, an illustrative method2900of operating the transmission120and the park system200in the engaged state1300may be embodied as, or otherwise include, a set of instructions that are executable by the control system2700. The method2900corresponds to, or is otherwise associated with, performance of the blocks described below in the illustrative sequence ofFIG.29. It should be appreciated, however, that the method2900may be performed in one or more sequences different from the illustrative sequence.

The illustrative method2900begins with block2902. In block2902, the controller2702receives input (e.g., from a user) to operate the transmission120and the park system200in the engaged state1300. For example, in block2902, the controller2702may receive input from the park input2712. In other embodiments, the controller2702may receive input from another input device indicative of desired operation in the engaged state1300. From block2902, the method2900proceeds to block2904.

In block2904of the illustrative method2900, the controller2702issues a control signal to the solenoid626to drive operation of the park system200in the engaged state1300in response to the input received in block2902. In the illustrative embodiment, the control signal issued by the controller2702in block2904directs delivery of the fluid pressure P1from the electro-hydraulic valve824to the actuation cavity840. Following issuance of the control signal in block2904, the groove1472should be aligned with the locking pin370as shown inFIG.14. From block2904, the method2900subsequently proceeds to block2906.

In block2906of the illustrative method2900, the controller2702issues a control signal to the locking pin370(e.g., the solenoid674) to cause extension of the locking pin370into the groove1472in response to the input received in block2902. As a result of the control signal issued by the controller2702in block2906, movement of the piston270along the longitudinal axis LA is blocked by the locking pin370and the piston270is maintained in the position corresponding to the engaged state1300. From block2906, the method2900proceeds to block2908.

In block2908of the illustrative method2900, the controller2702measures a position or angular orientation of one or more notches1140of the plate240about the rotational axis RA in response to the input received in block2902. It should be appreciated that measurement is performed in block2908with, and based on, a position of the one or more notches1140about the rotational axis RA that is detected by the position sensor360. In some embodiments, the position measured in block2908may provide a diagnostic indicator for evaluating operation of the park system200in the engaged state1300in the use of the transmission120.

Referring now toFIG.30, an illustrative method3000of operating the transmission120and the park system200in the disengaged state1500may be embodied as, or otherwise include, a set of instructions that are executable by the control system2700. The method3000corresponds to, or is otherwise associated with, performance of the blocks described below in the illustrative sequence ofFIG.30. It should be appreciated, however, that the method3000may be performed in one or more sequences different from the illustrative sequence.

The illustrative method3000begins with block3002. In block3002, the controller2702receives input (e.g., from a user) to operate the transmission120and the park system200in the disengaged state1500. For example, in block3002, the controller2702may receive input from the non-park input2714. In other embodiments, the controller2702may receive input from another input device indicative of desired operation in the disengaged state1500. From block3002, the method3000proceeds to block3004.

In block3004of the illustrative method3000, the controller2702issues a control signal to the solenoid626to drive operation of the park system200in the disengaged state1500in response to the input received in block3002. In the illustrative embodiment, the control signal issued by the controller2702in block3004directs delivery of the fluid pressure P2from the electro-hydraulic valve824to the actuation cavity840. Following issuance of the control signal in block3004, the groove1674should be aligned with the locking pin370as shown inFIG.16. From block3004, the method3000subsequently proceeds to block3006.

In block3006of the illustrative method3000, the controller2702issues a control signal to the locking pin370(e.g., the solenoid674) to cause extension of the locking pin370into the groove1674in response to the input received in block3002. As a result of the control signal issued by the controller2702in block3006, movement of the piston270along the longitudinal axis LA is blocked by the locking pin370and the piston270is maintained in the position corresponding to the disengaged state1500. From block3006, the method3000proceeds to block3008.

In block3008of the illustrative method3000, the controller2702measures a position or angular orientation of one or more notches1140of the plate240about the rotational axis RA in response to the input received in block3002. It should be appreciated that measurement is performed in block3008with, and based on, a position of the one or more notches1140about the rotational axis RA that is detected by the position sensor360. In some embodiments, the position measured in block3008may provide a diagnostic indicator for evaluating operation of the park system200in the disengaged state1500in the use of the transmission120.

Referring now toFIG.31, an illustrative method3100of operating the parking lock mechanism1900to manually shift the transmission120and the park system200to a non-park operating mode (e.g., a neutral mode) is shown. In some embodiments, one or more blocks of the illustrative method3100may be manually performed by a user. In other embodiments, one or more blocks of the illustrative method3100may be automatically performed by the control system2700, and in such embodiments, one or more blocks of the method3100may be embodied as, or otherwise include, a set of instructions that are executable by the control system2700. In any case, the method3100corresponds to, or is otherwise associated with, performance of the blocks described below in the illustrative sequence ofFIG.31. It should be appreciated, however, that the method3100may be performed in one or more sequences different from the illustrative sequence.

The illustrative method3100begins with block3102. In block3102, an automatic shift of the transmission120and the park system200to a non-park operating mode is attempted. To do so, in one example, the user may manipulate the non-park input2714to provide input to the controller2702indicative of the desired operation of the transmission120and the park system200in the disengaged state1500corresponding to the non-park operating mode. From block3102, the method3100proceeds to block3104.

In block3104of the illustrative method3100, a failure or fault condition preventing the automatic shift attempted in block3102is identified. In some embodiments, input provided by the position sensor360to the controller2702may be indicative of a lack of rotation of the plate240about the rotational axis RA in response to the receipt of input in block3102, and the lack of rotation detected by the position sensor360may serve to identify the fault condition in block3104. Additionally, in some embodiments, input provided to the controller2702by one or more sensors associated with the electro-hydraulic valve assembly220(e.g., the electro-hydraulic valve824) and/or the actuation linkage230(e.g., the piston270) may indicate a lack of fluid pressure delivered to the actuation cavity840in response to the receipt of input in block3102, and the lack of fluid pressure detected by the one or more sensors may serve to identify the fault condition in block3104. In any case, from block3104, the method3100proceeds to block3106.

In block3106of the illustrative method3100, the parking lock mechanism1900is installed on the transmission120. More specifically, in block3106, the user attaches the end1912of the lever1910to the shaft212and secures the end1912to the shaft212using the coupling nut1920, as discussed above with reference toFIG.19. From block3106, the method3100proceeds to block3108.

In block3108of the illustrative method3100, the lever1910is rotated relative to the main case202to the neutral operation position1950. As discussed above with reference toFIG.19, manual rotation of the lever1910to the neutral operating position1950drives rotation of the selector shaft212to place the park system200in the disengaged state1500. From block3108, the method3100proceeds to block3110.

In block3110of the illustrative method3000, the fastener1930is installed in the main case202to secure the lever1910to the case202in the neutral operating position1950. In some embodiments, performance of blocks3106-3110effects a manual shift of the transmission120and the park system200to the disengaged state1500associated with a non-park operating mode.

Referring now toFIG.32, an illustrative method3200of installing the piston270in the case extension204in the proper orientation is shown. In some embodiments, one or more blocks of the illustrative method3200may be manually performed by a user. In other embodiments, one or more blocks of the illustrative method3200may be automatically performed by the control system2700, and in such embodiments, one or more blocks of the method3200may be embodied as, or otherwise include, a set of instructions that are executable by the control system2700. In any case, the method3200corresponds to, or is otherwise associated with, performance of the blocks described below in the illustrative sequence ofFIG.32. It should be appreciated, however, that the method3200may be performed in one or more sequences different from the illustrative sequence.

The illustrative method3200begins with block3202. In block3202, the actuation linkage230is arranged at least partially in the main case202of the transmission120. In some embodiments, the actuation linkage230is at least partially assembled before being arranged in the case202in block3202. Additionally, in some embodiments, one or more structures of the actuation linkage230(e.g., the plate240, the biasing element250, the bushing280, the rod1130, the sleeve1260, and/or the biasing element1340) may be arranged at least partially in the main case202and assembled with one another in block3202. In any case, from block3202, the method3200proceeds to block3204.

In block3204of the illustrative method3200, the electro-hydraulic valve assembly220is installed and/or arranged in the case extension204of the transmission120. In some embodiments, the electro-hydraulic valve assembly220is at least partially assembled before being installed in the case extension204in block3204. Additionally, in some embodiments, one or more structures of the electro-hydraulic valve assembly220(e.g., the solenoid626, the electro-hydraulic valve824, and/or the clip) may be installed at least partially in the case extension204and assembled with one another in block3204. Regardless, from block3204, the method3200proceeds to block3206.

In block3206of the illustrative method3200, the case extension204is coupled to the main case202of the transmission120. In some embodiments, the case extension204may be coupled to the main body404of the main case202in block3206such that the case extension204extends downwardly from, and is positioned below, the main body404as best seen inFIGS.4and5. Additionally, in some embodiments, when the case extension204is coupled to the main body404in block3206, the secondary body406is coupled to the main body404such that the case extension204is covered and housed by the secondary body406as best seen inFIGS.4and5. In any case, from block3206, the method3200proceeds to block3212.

In block3212of the illustrative method3200, a user and/or the control system2700ensures the piston270is installed in the case extension204in the proper orientation. To do so, in the illustrative embodiment, blocks3208and3210are performed. In block3208, the user and/or the control system2700ensures the piston270is installed in the case extension204such that the piston270interacts with the anti-rotation pin1806. As discussed above with reference toFIG.18, interaction between the piston270and the anti-rotation pin1806restricts rotation of the piston270and may be indicative of installation of the piston270in the case extension204in the proper orientation. In block3210, the user and/or the control system2700ensures the piston270is installed in the case extension204such that the piston270(e.g., the post1876) interacts with the plate240(e.g., the mount extension1180) of the actuation linkage230. In some embodiments, in addition to the activities discussed above, block3212may include observing the orientation of the orientation indication bar1774to ensure the piston270is installed in the case extension204in the proper orientation.

Referring now toFIGS.33and34, in the illustrative embodiment, a magnet assembly3310is directly affixed to the piston270such that the magnet assembly3310, and at least one magnet3312carried by the magnet assembly3310, are movable with the piston270along, or in a direction parallel to, the longitudinal axis LA. As shown inFIG.33, a position3320of the magnet assembly3310corresponds to, or is otherwise associated with, the engaged operating state1300of the park system210. As shown inFIG.34, a position3422of the magnet assembly3310corresponds to, or is otherwise associated with, the disengaged operating state1500of the park system210. In comparison to the position3320of the magnet assembly3310shown inFIG.33, the magnet assembly3310is shifted to the right in the position3422shown inFIG.34.

In the illustrative embodiment, the magnet assembly3310is employed in conjunction with a position sensor3360. The illustrative position sensor3360is mounted to the transmission120(e.g., to the main case202) and configured to detect a position of the magnet(s)3312of the magnet assembly3310. In some cases, the position sensor3360may be configured to detect a position of the magnet(s)3312along, or in a direction parallel to, the longitudinal axis LA during movement between the positions3320,3422of the magnet assembly3310. In some embodiments, the sensor3360includes, or is otherwise embodied as, any electrical device or collection of electrical devices capable of detecting a position of the magnet(s)3312in use of the magnet assembly3310. Additionally, in some embodiments, the sensor3360includes, or is otherwise embodied as, a proximity sensor, such as a capacitive proximity sensor, an inductive proximity sensor, a hall effect sensor, or the like. Of course, in other embodiments, the sensor3360may include, or otherwise be embodied as, another suitable sensor. In any case, the sensor3360may be included in the control system2700and configured for communication with the controller2702in lieu of, or in conjunction with, the sensor360.

In at least some embodiments, the magnet assembly3310and the position sensor3360may form a portion of, or otherwise provide, a position sensing system that is implemented as an alternative to the aforementioned position sensing system including the indexing flange1160and the position sensor360. In such embodiments, the indexing flange1160and the position sensor360may be omitted entirely. That omission may facilitate compact packaging and space-saving compared to cases in which the indexing flange1160and the position sensor360are present.

Referring now toFIG.35, an illustrative housing3318of the magnet assembly3310includes a mount plate3522arranged in direct contact with a projection3572of the piston270, a U-shaped support bracket3524interconnected with the mount plate3522, and a magnet enclosure3526interconnected with the support bracket3524and arranged opposite the mount plate3522. The mount plate3522is adapted to receive a pair of fasteners3528through apertures (not shown) formed thereinto affix the housing3320to the projection3572of the piston270. The support bracket3524extends away from, and outwardly (e.g., in a radial direction) of, the mount plate3522to provide adequate clearance between the magnet enclosure3526and an outer diameter of the piston270. The magnet enclosure3526is sized to carry the magnet(s)3312in an interior thereof that is closed off by a cap3630.

Referring now toFIG.36, interaction between the cap3630and the magnet(s)3312held in the enclosure3526is illustrated in greater detail. The illustrative cap3630is formed to include clips3632,3634arranged opposite one another at the periphery of the inner diameter of the cap3630. The clips3632,3634may include, or otherwise be embodied as, resilient features (e.g., clips or tabs) configured for interaction (e.g., snap-fit) with corresponding features (e.g., recesses or grooves) disposed on the interior of the enclosure3526. Additionally, the cap3630includes clip springs or tangs3636,3638arranged radially inward of the clips3632,3634that are configured to directly contact the magnet(s)3312and apply a securing force thereto as indicated by the arrow SF. Application of the securing force SF to the magnet(s)3312illustratively secures the magnet(s)3312in place in the enclosure3526.

While the disclosure has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as exemplary and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected.