Modular assembly for a powertrain

Abstract

Modular powertrain assembly, comprising: a component housing (22) with first and second cavities (26, 24), wherein the first and second cavities (26, 24) are connected by an intermediate cavity passage (28); a drive shaft (40) which is arranged at least partially within the first cavity (26) of the housing (22), wherein the drive shaft (40) contains a first wheel (42) and receives force from a power source; an output shaft (48) which is arranged at least partially within the first cavity (26) of the housing (22); a first coupling device (56) which provides a controllable power transmission connection between the drive shaft (40) and the output shaft (48); a hydraulic control assembly (32) which provides hydraulic control signals for controlling, at least partially, the power flow from the drive shaft (40) to the output shaft (48); and a hydraulic control system that receives hydraulic control signals from the hydraulic control assembly (32) and directs the received hydraulic control signals to control, at least in part, the flow of power from the drive shaft (40) to the output shaft (48); wherein a high-low reverse-force intermediate shaft with second and third coupling devices (72, 74) includes a first wheel connection with the first wheel (42) of the drive shaft (40), a second wheel connection via the second coupling device (72) with the output shaft (48) and a third wheel connection via the third coupling device (74) and a first idle wheel with the output shaft (48); wherein a high-low intermediate shaft (130) with a fourth coupling device (138) includes a fourth wheel connection with the first wheel (42) of the drive shaft (40) and a fifth wheel connection via the fourth coupling device (138) with the output shaft (48); wherein a force reversing intermediate shaft (150) with a fifth coupling device (158) includes a sixth wheel connection with the first wheel (42) of the drive shaft (40) and a seventh wheel connection via the fifth coupling device (158) and a second idle wheel with the output shaft (48); wherein the assembly housing (22) is configured to separately accommodate, without modification of the assembly housing (22), each of the high-low force reversal intermediate shaft, the high-low intermediate shaft (130) and the force reversal intermediate shaft (150); and wherein the hydraulic control system directs the received hydraulic control signals separately to at least one of the second and third coupling devices (72, 74), to the fourth coupling device (138) or to the fifth coupling device (158), depending on whether the high-low force reversal intermediate shaft, the high-low intermediate shaft (130) or the force reversal intermediate shaft (150) is currently accommodated by the assembly housing (22).

Description

[0001] This disclosure relates to transmission of mechanical power, including transmission of mechanical power via a transaxle assembly of a work vehicle.

[0002] A flow channel structure is known from the prior art with which a flow channel can be easily formed in a flange member and a flange member is made compact. For example, DE 600 10 631 T2 discloses a flow channel structure for a flange member with a pressed-in shaft, which is formed by pressing a shaft member into a press-fit bore of a flange member. The shaft member is provided with flow channels having openings in an outer peripheral surface of the shaft member. The flange member is provided with blind holes which are designed such that they extend linearly at right angles to the shaft axis from outer peripheral surfaces of the flange member through the press-fit bore and terminate at their free end portions inside the flange member.Furthermore, connecting bores are provided which extend from a side surface of the flange member in the axial direction and communicate with the portions of the blind holes extending from the press-fit bores to their free ends. Second flow channels are formed from the portions of the blind holes extending from the press-fit bore to their free ends and to the connecting bores. The shaft member is positioned such that the portions of the blind holes in the second flow channels opening into the press-fit bore and the first flow channels communicate with each other, thereby forming a flow channel structure.

[0003] Depending on various factors, including the type of operations to be performed, the operating environment, the desired cost or complexity of the systems involved, and so on, it may be useful to provide several different types of drivetrains (and drivetrain components) for different vehicles (or other platforms). For example, a relatively inexpensive and simple work vehicle may provide a limited number of gear ratios between an engine and the vehicle's wheels, while a more expensive and complex work vehicle may provide a larger number of gear ratios.

[0004] While such variation in powertrain design can offer more upscale consumer options, it can also lead to increased complexity for manufacturing facilities and assembly lines. For example, if multiple powertrain designs are applicable to a particular vehicle type (e.g., a particular tractor), this can require a large number of components, manufacturing processes, assembly lines, and so on. This can introduce undesirable costs and complexity.

[0005] A modular assembly for a powertrain is disclosed. According to one aspect of the disclosure, an assembly housing includes first and second cavities connected by an intercavity passageway. An input shaft and an output shaft, connected by a first clutch, are disposed at least partially within the first cavity. A hydraulic control device provides hydraulic control signals for at least partially controlling the first clutch device. A hydraulic control system receives hydraulic signals from the hydraulic control device and directs the signals for controlling power flow from the input shaft to the output shaft. The control system may include a hydraulic hollow shaft insert disposed at least partially within the intercavity passageway, the hydraulic hollow shaft passageway including a plurality of control passageways.

[0006] In certain embodiments, a plurality of intermediate shafts are provided, which can be separately housed in the housing without modifying the housing. The intermediate shafts can contain various transmission and clutch devices and a plurality of associated power passages. The hydraulic hollow shaft insert can route hydraulic control signals for controlling the plurality of clutch devices separately from the hydraulic control device to the plurality of power passages of the intermediate shafts.

[0007] In certain embodiments, the hollow hydraulic shaft insert may include a cylindrical body, a mounting flange, and a plurality of hydraulic input features (e.g., a plurality of circumferential grooves) in hydraulic communication with the hydraulic control assembly. The cylindrical body may include an internal bore configured to separately receive each of the plurality of intermediate shafts. The cylindrical body may further include sets of control passages (e.g., sets of radial passages), each set extending from an associated hydraulic input feature to the bore. Hydraulic control signals from the hydraulic control assembly may be routed separately from the hydraulic input features through the sets of associated control passages to the plurality of power passages of the intermediate shafts, depending on the particular intermediate shaft received through the bore.

[0008] Further disclosed is a hydraulic hollow shaft insert for routing hydraulic control signals from a hydraulic control assembly to various components contained within a housing. The hydraulic hollow shaft insert comprises a cylindrical body with an internal bore, a mounting flange for attaching the cylindrical body to the housing, a plurality of hydraulic input features in hydraulic communication with the hydraulic control assembly (32), and a plurality of sets of control passages.Each set of control passages extends from the inner bore to an associated hydraulic input feature included in the plurality of hydraulic input features, wherein a hydraulic control signal is passed from the hydraulic control assembly to a hydraulic input feature included in the plurality of hydraulic input features through an associated set of control passages included in the plurality of sets of control passages for controlling an associated device. Also included is a high-low power reversing intermediate shaft having first and second clutch devices, including a first gear connection to a first gear of an input shaft contained in the housing, a second gear connection via the first clutch device to an output shaft contained in the housing, and a third gear connection via the second clutch device and a first idler gear to the output shaft.A high-low intermediate shaft with a third clutch device includes a fourth gear connection to the first gear of the input shaft and a fifth gear connection via the third clutch device to the output shaft. A power reversing intermediate shaft with a fourth clutch device includes a sixth gear connection to the first gear of the input shaft and a seventh gear connection via the fourth clutch device and a second idler gear to the output shaft. The inner bore is configured to separately receive each of the high-low power reversing intermediate shaft, the high-low intermediate shaft, and the power reversing intermediate shaft. The hydraulic control signal is routed via the associated set of control passages to at least one of the first and second clutch devices, the third clutch device, or the fourth clutch device, respectively.The high-low power reversing intermediate shaft includes a first set of internal power passages in communication with the first and second clutch devices. The high-low power reversing intermediate shaft includes a second set of internal power passages in communication with the third clutch device, and the power reversing intermediate shaft includes a third set of internal power passages in communication with the fourth clutch device.

[0009] Further details of one or more implementations are set forth in the accompanying drawings and the following description, as well as the dependent claims. Other features and advantages will become apparent from the description, drawings, and claims. Fig. 1 is a side view of an example vehicle that may include a modular powertrain assembly according to the present disclosure; Fig. 2 is a schematic view of an example transaxle assembly of the example vehicle of Fig. 1; Fig. 3 is a sectional view of certain components of an exemplary modular powertrain assembly used in the transaxle assembly of Fig. 2 may be included, along the plane AA of Fig. 2; Fig. 4 is an enlarged partial sectional view of a hydraulic hollow shaft insert and an intermediate shaft used in the modular assembly of Fig. 3 are included, from the same perspective as Fig. 3; Fig. 5A is a perspective view of the hydraulic hollow shaft insert of Fig. 4; Fig. 5B is a sectional view of the hydraulic hollow shaft insert of Fig. 4 along the plane BB of Fig. 5A; Fig. 5C is a sectional view of the hydraulic hollow shaft insert of Fig. 4 along the plane CC of Fig. 5A; Fig. 6 is a sectional view of certain components of another exemplary modular powertrain assembly used in the transaxle assembly of Fig. 2 may be included, along plane AA of Fig. 2; Fig. 7 is a sectional view of certain portions of yet another exemplary modular powertrain assembly used in the transaxle assembly of Fig. 2 may be included, along the plane AA of Fig. 2; Fig. 8 is a sectional view of certain portions of yet another exemplary modular powertrain assembly used in the transaxle assembly of Fig. 2 may be included, along the plane AA of Fig. 2; Fig. 9A is a perspective view of an exemplary hydraulic hollow shaft insert for the assembly of Fig. 8; Fig. 9B is a sectional view of the hydraulic hollow shaft of Fig. 9A along the plane DD of Fig. 9A; Fig. 10 is a perspective view of an exemplary intermediate shaft that may be included in a modular powertrain assembly; Fig. 11 is a bottom view of the exemplary intermediate shaft of Fig. 10; Fig. 12 is a sectional view of certain components of the transaxle assembly of Fig. 2 along the plane EE of Fig. 2; and Fig. 13 is a sectional view of certain components of the transaxle assembly of Fig. 2 along the plane FF of Fig. 2.

[0010] Like reference numerals in the different drawings indicate like elements.

[0011] The following describes one or more embodiments of the disclosed assembly for a powertrain (or the disclosed vehicle) as shown in the accompanying drawing figures briefly described above. Various modifications may be contemplated by those skilled in the art.

[0012] The following discussion describes various example configurations of shafts, gears, and other power-transmitting elements. It should be understood that various alternative configurations are possible within the spirit of the disclosure. For example, various configurations may utilize multiple shafts instead of a single shaft (or a single shaft instead of multiple shafts), dispose one or more idler gears between different shafts or gears for transmitting rotational power, utilize various known mechanisms for connecting gears or other devices to shafts for co-rotating or independently rotating the gears and shafts, etc.It is further understood that the indication that certain transmissions are rigid (or otherwise configured) with respect to a particular shaft is not intended to limit the disclosure, and that various alternative configurations providing similar power transmission functionality may be possible. Likewise, it is understood that, although numerous examples below refer to vehicle platforms, the principles of the disclosure may additionally (or alternatively) apply to non-vehicle platforms (e.g., stationary powered platforms).

[0013] As stated above, it may be useful to provide multiple options for configuring a powertrain for a particular vehicle (or vehicles, or other platform). For example, it may be useful to provide different transaxle configurations for a particular tractor (or other work vehicle) to provide the consumer with a variety of powertrain choices. In certain implementations, simpler (and potentially less expensive) configurations might address certain consumers or be useful for certain applications, while more complex (and potentially more expensive) configurations might address different consumers or be useful for other applications. For example, a less expensive configuration might provide fewer gear ratio options than a more expensive configuration, it might not include a power reverser option, etc., which might appeal to a specific subset of users. However, introducing such a variety of choices could lead to increased manufacturing complexity, as it could lead to an increase in the number of possible parts for the vehicle (or vehicles or other system) in question.

[0014] To mitigate this trend toward manufacturing complexity (and the corresponding potential increase in manufacturing costs), it may be useful to provide a modular assembly for different sections of a powertrain. For example, different powertrains may include a transaxle or other assembly for transmitting power from a power source (e.g., an engine) to a power consumer (e.g., multiple vehicle wheels, a power take-off (PTO), etc.). In certain embodiments, certain aspects of such a transaxle (or other assembly) may be implemented to provide a common platform for a variety of different power-delivery configurations.For example, if a section of the transaxle (or other assembly) includes an intermediate shaft transmission, various components of the intermediate shaft transmission may be configured to be interchangeable without modification of the larger transaxle system, allowing for the modular assembly of numerous powertrain configurations on a common platform. (Various examples below may specifically address such a transaxle assembly. However, it is understood that other configurations may be possible, including configurations without a transaxle.)

[0015] In certain embodiments, a transaxle (or other powertrain) housing may house an input shaft and an output shaft. For example, the input shaft may receive power from an internal combustion engine, and the output shaft may supply power to a power-shift transmission also included in the transaxle. With appropriate configuration of the housing and the two shafts, the housing may be capable of separately housing input and output shafts of a variety of configurations, including with (or without) various clutch packs or other power steering assemblies. The housing may also separately house one of various intermediate shafts, which, in conjunction with various associated clutch packs or other power steering assemblies, may enable a variety of gear ratios (including 1:1 and reverse ratios) between the input shaft and the output shaft.As with the input and output shafts, with appropriate configuration of the housing and the various intermediate shafts, the housing may be capable of separately accommodating multiple intermediate shaft types without significant modification. This may, for example, allow a common housing (and potentially a common input and output shaft) to be used with multiple intermediate shaft assemblies to provide multiple intermediate shaft transmission types within the same transaxle envelope (i.e., via selective inclusion of a particular one of the various intermediate shafts). Indeed, with appropriate configuration, common basic parts for the various intermediate shaft assemblies (e.g., common shaft castings) may also be used, with variations between different assemblies being provided for by relatively simple machining operations applied to the common basic parts.These arrangements can enable relatively low-cost, and essentially modular, assembly of vehicles or vehicle subsystems with a wide variety of features, capabilities, and costs.

[0016] Furthermore, and as indicated above, intermediate shaft assemblies in such modular designs (as well as various input and output configurations) may include one or more clutch devices (e.g., one or more wet clutch packs). Accordingly, it may be useful to provide a device (or device assembly) for enabling the control of each of these clutch devices in each of the various possible configurations without requiring significant component modification or excessive numbers of additional parts. Thus, for example, a hydraulic hollow shaft insert (also referred to simply as a "hydraulic hollow shaft" or "hollow shaft") may be provided, which may be mounted within the transaxle (or other) housing. In certain embodiments, such a hollow shaft may separately support the rotating intermediate shafts at one end of the intermediate shaft (i.e.,Each intermediate shaft may individually support one of the intermediate shafts, depending on which intermediate shaft is used in the overall assembly, and may include various flow passages extending from external input features of the hollow shaft (e.g., circumferential grooves on the hollow shaft) to an internal bore of the hollow shaft in which the intermediate shafts rotate. The input features, in turn, may communicate with various ports or passages through the transaxle housing configured to receive hydraulic control signals from various control manifolds or other control assemblies (e.g., by selectively drilling certain flow passages through the housing, by specially configuring the control manifold(s), etc.).Furthermore, inlet features on the various intermediate shafts can align with various flow passages through the hollow shaft, which in turn can direct control signals to a specific clutch pack (or other control device) associated with the intermediate shaft. For example, hydraulic flow through a specific set of hollow shaft flow passages can be directed through specific inlet features into a specific set of intermediate shaft flow passages and thereby to a specific clutch pack (or other control device).

[0017] Accordingly, specific control logic can be implemented through a specific hydraulic control manifold (or other control assembly), with a hydraulic thimble insert routing control signals from the manifold to a dedicated control device (for example, through a supported intermediate shaft to a dedicated clutch pack on the intermediate shaft). With a properly configured thimble shaft, such control logic can then be varied for different powertrain configurations without requiring a change (or significant changes) to the hydraulic thimble, housing, input shaft, output shaft, basic intermediate shaft design, or various other components.For example, using the same hydraulic hollow shaft, different control schemes can be implemented by selecting different control distributors, using different intermediate shafts (and different associated control devices), selectively drilling different sets of control passages in a standardized intermediate shaft (corresponding to different arrangements of associated control devices), etc.

[0018] A hollow hydraulic shaft as described herein may also provide various additional benefits beyond the interchangeability of control manifolds (or control logic), intermediate shaft assemblies, or other drivetrain components. For example, in cast housings with multiple cavities, the use of a cylindrical hollow shaft may enable the creation of a casting with a larger hole between the cavities, which may help prevent casting breakage and the generation of excessive casting scrap. Furthermore, in various embodiments, a hollow shaft may provide a side surface against which a support bearing for the various intermediate shafts may be seated, which may increase the ease of system assembly.

[0019] As will be apparent from the discussion herein, the disclosed modular assembly can be advantageously used in a variety of settings and with a variety of machines. For example, with reference to Fig. 1, the disclosed assembly (e.g., as included in the drive train 12 with the engine 12a) may be included in a vehicle 10. In Fig. In Figure 1, the vehicle 10 is depicted as a tractor with a drivetrain 12. However, it should be understood that other configurations may be possible, including configurations with the vehicle 10 as another type of tractor, a harvester, a logging tractor, a grader, or any of various other types of work vehicles. It should also be understood that the disclosed drivetrain assembly may also be used in non-work vehicles and non-vehicle applications (e.g., stationary powered equipment).

[0020] With reference to Fig. 2, the powertrain 12 may include the transaxle 20. The housing 22 may be included at an input end of the transaxle 20 and include cavities 24 and 26 separated by the intermediate cavity passage 28. The housing 22 may include (e.g., within one or both of the cavities 24 and 26) the internal assembly 30, such as an intermediate shaft gear assembly, including the hydraulic hollow shaft 82 within the passage 28.

[0021] As discussed in more detail below, the assembly 30 (e.g., configured as one of various intermediate shaft transmissions) may include various control devices, such as various wet clutch packs. To control such devices, the hydraulic control assembly 32 (e.g., a hydraulic manifold with various configurations) may be mounted on the exterior of the housing 22. The control assembly 32 may, for example, include various pressure sensors and control valves that may employ various hydraulic control logic schemes to control various devices (e.g., various clutches) within the assembly 30. Accordingly, various inlet ports (in Fig. 2 not shown) on the housing 22 such that they are located at different outlet openings (in Fig. 2 not shown) of the control assembly 32 to enable the transmission of hydraulic control signals from the control assembly 32 into the housing 22. Such inlet openings may, for example, direct certain of the received hydraulic signals to the hollow hydraulic shaft 82 so that the hollow shaft 82 may conveniently route the signals for actually controlling various devices included in the assembly 30 (for example, in conjunction with various other power passages).

[0022] In certain embodiments, the control assembly 32 may be configured modularly. For example, the main section 32a may provide control flow logic for a first set of configurations (or devices) of the internal assembly 30, and the supplemental section 32b may provide supplemental control flow logic for additional configurations (or devices) of the internal assembly 30. Thus, for example, the main section 32a, but not the supplemental section 32b, may be mounted to the housing 22 in a number of configurations of the assembly 30 (with appropriately drilled inlet openings to the housing 22). If desired, the supplemental section 32b (or various other control devices) may also be mounted to the housing 22 (with additional inlet openings to the housing 22 provided as appropriate for transmitting control signals to appropriate components of the assembly 30).In certain embodiments, sections 32a and 32b may share various aspects of a main hydraulic circuit, including a common pressure source, a common fluid reservoir, etc. For example, reservoir and pressure lines (not shown) for section 32b may be directed upward (as viewed from FIG. Fig. 2) extend toward section 32a, with suitable passage openings (not shown) being incorporated into section 32a for connecting these lines of section 32b to corresponding lines within section 32a. Various other configurations may also be possible, including configurations with more or fewer control assemblies, configurations with pneumatic or other control assemblies, configurations in which different control assembly sections access different pressure sources, etc.

[0023] With reference to Fig. 3, the exemplary internal assembly 30 is depicted as a high-low power reversing intermediate shaft transmission (e.g., an intermediate transmission with high and low gears and a reverse gear). As illustrated, for example, the input shaft 40 within the housing 22 may receive power output from an engine (not shown) of the vehicle 10. The input shaft 40 may include the gear 42, which may be integral with (or otherwise rotatably attached to) the shaft 40, as well as hydraulic inlet grooves 44, or various other features. (As indicated above, it is understood that different gears may be attached to different shafts in various ways—rotatable, slidable, fixed, or otherwise.) The output shaft 48, which may, for example, be an input shaft for a downstream power-shift transmission (not shown), may also be contained within the housing 22.Shaft 48 may be rotatably supported on shaft 40 via bearing 54 and may include gears 50 and 52, which may be integrally formed with (or otherwise rotatably attached to) shaft 48. Clutch device 56 (in . Fig. 3 as a wet clutch pack, although it is understood that various other clutch devices may be utilized) may be disposed between shafts 40 and 48 such that when clutch device 56 is engaged, power may be transmitted from shaft 40 to shaft 48 via clutch 56, but when clutch device 56 is disengaged, shaft 48 may generally rotate freely about shaft 40 via bearing 54. In certain embodiments, hydraulic control signals for clutch device 56 may be provided from control assembly 32 via hydraulic inlet grooves 44 (and associated power passages (in Fig. 3) from the control assembly 32 through the housing 22) and then routed within the housing 22 to the clutch device 56 in various known manners. In certain embodiments, an additional output shaft (e.g., power take-off ("PTO") 58) may also be provided.

[0024] An intermediate shaft, such as intermediate shaft 62, with various internal power passages 64 may also be contained within housing 22. One end of intermediate shaft 62 may extend into hollow hydraulic shaft 82 and be supported by bearing 80, which may be seated against one or more features or side surfaces of hollow shaft 82. Intermediate shaft 62 may include gear 66, which may be rotatably attached to (or integrally formed with) intermediate shaft 62. Intermediate shaft 62 may also include gears 68 and 70 and associated clutch devices 72 and 74, respectively. Gear 68 may be engaged with gear 50 of shaft 48, and gear 70 may be engaged with idler gear 76, which in turn may be engaged with gear 52 of shaft 48. In this way, the intermediate shaft 62 can, for example, always rotate with the drive shaft 40 (via the wheels 42 and 66), whereby the wheels 68 and 69, respectively,However, 70 can only rotate with the intermediate shaft 62 when the clutch device 72 or 74 is engaged. Accordingly, the assembly 30a can be viewed as a high-low power reversing intermediate shaft transmission in which engagement of the clutch 56 and disengagement of the clutches 68 and 70 can enable direct power transmission from the shaft 40 to the shaft 48, engagement of the clutch 68 and disengagement of the clutches 56 and 70 can impose a speed reduction between the shafts 40 and 48, and engagement of the clutch 70 and disengagement of the clutches 56 and 68 can reverse the direction of rotation of the shaft 48 with respect to the shaft 40.

[0025] As indicated above and discussed in more detail below, hydraulic control logic for the clutches 72 and 74 may be implemented by the control assembly 32, with hydraulic signals from the assembly 32 being passed through the housing 22 through the hollow hydraulic shaft 82 to various internal flow passages 64 of the intermediate shaft 62. Referring also, for example, to Fig. 4 to 5C, an example configuration of the hollow shaft 82 is shown in detail. As indicated above, the intermediate cavity passage 28 may extend between the housing cavities 24 and 26. For example, in certain embodiments, the passage 28 may be generally cylindrical, and the hollow shaft 82 may be configured with a generally similar cylindrical shape so that the hollow shaft 82 may be mounted with minimal clearance within the passage 28. The mounting flange 84 may be provided on the hollow shaft 82 for attachment (e.g., via bolts or other fasteners) to various features of the housing 22 (e.g., the generally annular housing flange 86). The bore 90, which may be a blind hole with end wall 92, may extend into the hollow shaft 82 and may be configured to receive one end (e.g., the left end as viewed from Fig. 4) the intermediate shaft 62 (or another intermediate shaft). In certain embodiments, with the intermediate shaft 62 fully inserted into the bore 90, the axial gap 94 may remain between the inserted end of the intermediate shaft 62 and the end wall 92 of the bore 90. As also noted above, the intermediate shaft 62 may be rotatably supported by the bearing 80, which may be seated against the hollow shaft 82. Various hydraulic or other seals or gaskets (e.g., the gaskets 98) may be provided as appropriate.

[0026] The hollow shaft 82 may be configured to receive hydraulic control signals from the control assembly 32 (for example, via passages (in Fig. 4 not shown) through the housing 22) and relay these signals for controlling various components (e.g., various clutch devices) of the assembly 30. In certain embodiments, hydraulic input features, such as circumferential inlet grooves 100, may be disposed on an outer portion of the hollow shaft 82. These features may communicate with various sets of control passages 104 extending from the outer portion of the hollow shaft 82 (e.g., radially) to the bore 90. Various seal grooves 102 configured to receive various seals (e.g., various annular seal members included in the seals 98) may be provided to ensure hydraulic isolation of the various grooves 100 (and the associated sets of control passages 104) from one another. As in Fig. 4 to 5C, for example, three circumferential inlet grooves 100a, 100b, and 100c may be provided, each of which may communicate with three sets of four radial control passages 104a, 104b, and 104c. This may, in certain embodiments, correspond to the ability to control three (or more) different devices (e.g., three different wet clutches) via the hollow shaft 82, since each groove 100 and associated set of passages 104 may provide a different routing path for hydraulic control signals.For example, if an intermediate shaft inserted into the hollow shaft 82 is provided with three different sets of internal flow passages, with an inlet of each set aligned with a respective set of control passages 104 and an outlet of each set aligned with a respective control inlet for one of the three different clutch devices, each of the clutch devices may be individually and separately controlled by a control signal originating in the control assembly 32 and passed through the hollow shaft 82 through the appropriate set of control passages 104. (In certain embodiments, one or more such intermediate shaft passages may open at the axial end of the intermediate shaft rather than along the intermediate shaft circumference, thereby receiving a control signal via the axial gap 94 and, for example, the control passages 104c.)

[0027] With further specific reference to Fig. 3 and Fig. 4, it can be seen that the upper flow passage 64a of the intermediate shaft 62 can extend axially along the intermediate shaft 62 from the axial gap 94 to a radial (or other) passage into the clutch device 74. This allows a signal from the control assembly 32, passed through the hollow shaft 82 to the axial gap 94 (via the control passage 104c), to be used to control the clutch 74. Likewise, the lower flow passage 64b can extend axially along the intermediate shaft 62 from a radial (or other) inlet aligned with the control passage 104b to a radial (or other) outlet into the clutch device 72. This allows a signal from the control assembly 32, passed through the hollow shaft 82 through the control passage 104b, to be used to control the clutch 72.Accordingly, it is understood that numerous configurations of an intermediate shaft and numerous controllable devices (e.g., associated clutch devices) may be provided, with control for such devices being accomplished by appropriately aligning (e.g., by appropriate cross-drilling or other machining) intermediate shaft passage inlets with particular control passages 104 (or axial gap 94) and intermediate shaft passage outlets with control inlets for the various devices. In certain embodiments, as shown in FIG. Fig. 4, a plurality of intermediate shaft passages (e.g., both of passages 64a and 64b) extend to the axial end(s) of an intermediate shaft and the axial gap 94, with a plug (e.g., plug 96) provided to prevent flow from the axial gap 94 into certain ones of the passages (e.g., passage 64b).

[0028] As stated above, various other configurations may also be possible, using the same housing 22 (or a similar housing) and various shafts having the same (or similar) configuration as the shafts 40, 48 and 62 (e.g., various shafts having a similar basic configuration, with various other internal passages, attached wheels, attached coupling devices, etc.). For example, with reference to Fig. 6, the exemplary internal assembly 30b is depicted as a high-low intermediate shaft transmission (e.g., an intermediate shaft transmission with high and low gears). As depicted, for example, the input shaft 40 and the output shaft 48, which are similar to the embodiment of Fig. 3 may again be contained in the housing 22. The wheel 42, the hydraulic inlet grooves 44, the bearing 54, the wheel 50 and the clutch device 56 (for example, a wet clutch pack) may also be included and may be similar to the description of the embodiment of Fig. 3 work above.

[0029] Accordingly, it will be appreciated that many of the same (or similar) components are suitable for the embodiment of Fig. 6 (and others) as they are used for the embodiment of Fig. 3 are used.

[0030] An intermediate shaft, such as intermediate shaft 130, with various internal power passages 132, may also be contained within housing 22. Intermediate shaft 130 may be configured similarly to intermediate shaft 62 and, in certain embodiments, may be based on the same (or a similar) basic design, varying primarily due to different configurations of power passages 132 (for intermediate shaft 130) and power passages 64 (for intermediate shaft 62) and due to the inclusion (or exclusion) of various different gears and coupling devices. For example, while gears 68 and 70 and coupling devices 72 and 74 may be attached to intermediate shaft 62, gear 136 and coupling device 136 may be attached to intermediate shaft 130.Likewise, passages 64 may be configured to conduct hydraulic control signals to both of the clutch devices 72 and 74, while flow passage 13 may be configured to conduct hydraulic control signals only to the clutch device 136. In certain embodiments, this may be achieved by casting the intermediate shafts 130 and 62 from the same (or similar) molds and then machining (e.g., drilling) appropriate inlet and outlet passages for the axial intermediate shaft passages only for the clutch devices to be mounted on the particular intermediate shaft.Alternatively, a similar (or identical) intermediate shaft base without axial passages may be provided (e.g., cast) for both configurations, with appropriate axial passages 64 or 132 (and matching inlets and outlets) machined depending on the particular clutch (or other) devices to be incorporated.

[0031] As with the intermediate shaft 62, one end of the intermediate shaft 130 may extend into the hollow hydraulic shaft 82 and may be supported by the bearing 80, which may seat against one or more features or side surfaces of the hollow shaft 82. The intermediate shaft 130 may include the gear 134, which may be rotatably attached to (or formed integrally with) the intermediate shaft 134 and engageable with the gear 42. (In certain embodiments, the gear 134 may be similar to or identical to the gear 66.) As indicated above, the intermediate shaft 130 may also include the gear 136 and the associated clutch device 138. The gear 136 may be engageable with the gear 50 of the shaft 48, but may be rotatably attached to the intermediate shaft 130 so that the gear 136 can always rotate with the gear 50, but not always rotate with the intermediate shaft 130.In this manner, for example, the intermediate shaft 130 may always rotate with the input shaft 40, but the gear 136 may only rotate with the intermediate shaft 130 (and potentially drive rotation of the output shaft 48) when the clutch device 138 is engaged. Accordingly, the assembly 30b may be viewed as a high-low intermediate shaft transmission, where engagement of the clutch 56 and disengagement of the clutch 138 may enable direct power transmission from the shaft 40 to the shaft 48, and engagement of the clutch 138 and disengagement of the clutch 56 may impose a speed reduction between the shafts 40 and 48 (via the intermediate shaft 130). The control assembly 32 may accordingly be configured to supply appropriate signals to the hollow shaft 82 for appropriate routing (e.g., through the axial control passage 104c and the axial gap 94 to the passage 132 and to the clutch 138).

[0032] With reference also to Fig. 7, a power reversing intermediate shaft transmission may be provided through the use of the similar intermediate shaft 150 with gears 154 and 156 and the clutch device 158. In such a configuration, engagement of the clutch 56 and disengagement of the clutch 158 may enable direct power transmission from the shaft 40 to the shaft 48, and engagement of the clutch 158 and disengagement of the clutch 56 may reverse the direction of rotation of the shaft 48 relative to the shaft 40 (via the intermediate shaft 150 and the idler gear 160).As indicated above, such a configuration is achievable through the use of the same or similar parts as other embodiments contemplated herein, including through the use of the same (or similar) configurations of the input shaft 44 and associated devices, the output shaft 48 and associated devices, and a common intermediate shaft configuration, with appropriate machining (or other processing) to provide the appropriate configuration of the current passages 152. Likewise, the control assembly 32 may be configured to supply appropriate signals to the hollow shaft 82 for conduction to control the various coupling devices. For example, as shown in FIG. Fig. 7, control for the clutch 158 may be conducted through the hollow shaft 82 through the control passages 104c and the axial gap 94 to the upper intermediate shaft passage 152a, while the lower passage 152b may be included in the intermediate shaft 150 (e.g., because it is pre-cast or pre-drilled into a basic intermediate shaft design), but may not provide hydraulic connection to any controllable device (e.g., because no inlet or outlet passages have been provided).

[0033] Still other configurations may also be possible. For example, in certain embodiments, additional (or different) gears and coupling devices may be provided beyond those specifically illustrated. For example, in certain embodiments, an additional clutch and gear may be provided for the intermediate shaft 62 ( Fig. 3) may be provided so that all three sets of control passages 104 of the hollow shaft 82 may be used to control the engagement (and disengagement) of the three different gears. This may, for example, result in an intermediate shaft transmission with two forward and one reverse gear ratios and a direct connection between the input and output shafts (for example, via the clutch 56). Furthermore, in certain embodiments, an even greater number of gears (and associated devices) may be controlled by incorporating additional sets (not shown) of control passages 104 and inlet grooves 100 into the hollow shaft 82 or configuring intermediate shaft flow passages and control logic (such as implemented by the control assembly 32) to control the multiple devices via a single intermediate shaft flow passage.For example, if various intermediate shaft devices (e.g., various coupling devices) were configured such that pressurization of a single intermediate shaft flow passage would cause complementary actuation of the devices (e.g., engagement of one such device and disengagement of another such device), the number of devices to be controlled via the hollow shaft 82 may exceed the number of sets of control passages 104 within the hollow shaft 82 (and the corresponding number of intermediate shaft passages).

[0034] Furthermore, in certain embodiments, no intermediate shaft may be provided in the inner assembly 30. For example, with reference also to Fig. 8, the inner assembly 30d does not include an intermediate shaft. Therefore, the assembly 30d can simply operate as a wet clutch transmission in which power is transmitted from the input shaft 44 to the output shaft 48 when the clutch 56 is engaged, but is not transmitted when the clutch 56 is disengaged. In such a case, the plug 170 can be provided instead of the bearing 80 to prevent hydraulic leakage through the plug 82. Alternatively, with reference also to Fig. 9A and Fig. 9B, the intermediate shaft 82a may be provided, which may include the mounting flanges 84a and the bore 90a with the end wall 92a, but no input grooves or control passages.

[0035] As indicated above, it may be possible to utilize various standardized components, including standardized intermediate shaft templates, in the disclosed modular assembly. With reference also to Fig. 10 and Fig. 11, for example, the exemplary standardized intermediate shaft 180 may be provided. The intermediate shaft 180 may, for example, be configured to insert into the bore 90 of the hollow hydraulic shaft 82 and to accommodate various configurations of gears, coupling devices, etc., according to the desired configuration of the transaxle 20 and internal assembly 30. In certain embodiments, the intermediate shaft 180 may be manufactured to always include a number of internal flow passages (e.g., flow passages 182, 184, and 186). For example, the intermediate shaft 180 may be cast to include the axial portions of passages 182, 184, and 186, or these axial portions may be machined (e.g., drilled) into the intermediate shaft 180 as standard practice.Depending on the particular configuration of assembly 30 (e.g., the particular coupling devices included in assembly 30), radial inlet and outlet passages for flow passages 182, 184, and 186 may then be provided (e.g., by cross-drilling intermediate shaft 180). For example, inlet passages may be provided for reaching passages 182, 184, and 186, respectively, from different points that represent convenient inlet locations (e.g., locations aligned with different control passages 104 of hollow shaft 82), and outlet passages may be provided for reaching passages 182, 184, and 186, respectively, from different points that represent convenient outlet locations (e.g., as aligned with control inlets for different coupling devices).In certain embodiments, such inlet and outlet locations (and accordingly the passages 182, 184 or 186) may be used for cooling or lubrication purposes instead of (or in addition to) controlling the clutches or other devices.

[0036] In certain embodiments, and as specifically described in Fig. 10 and Fig. 11, three sets of inlets and outlets may be provided for the flow passages 182, 184, and 186, which may correspond to controlling (and / or cooling) three (or more) different components of the assembly 30 (e.g., three different clutch devices). As shown, the passage 182 may have an inlet on the left axial side surface of the intermediate shaft 180 (e.g., as aligned with the axial gap 94) and outlets 196 and 198 (e.g., cross-drilled or otherwise machined) at the circumferential grooves 204 and 206 on the body of the intermediate shaft 180. The passage 184 may have an inlet 188 machined at the groove 192 (e.g., as aligned with the control passages 104a of the hollow shaft 82) and an outlet 200 machined at the groove 208.Finally, passage 186 may include inlet 190 machined at groove 190 (e.g., as aligned with control passages 104b of hollow shaft 82) and outlet 202 machined at groove 210. Thus, for example, passage 182 may provide cooling or lubrication for various components (via control passages 104c and axial gap 94), passage 184 may provide control for a first clutch device (via control passages 104a), and passage 186 may provide control for a second clutch device (via control passages 104b). It is understood that various other configurations are possible based on the configuration of passages 182, 184, 186 (and others) and the associated inlets and outlets.For example, various embodiments may include a greater or lesser number of axial passages (e.g., as cast or machined into a common intermediate shaft design), different numbers or locations of inlets and outlets to the various intermediate shaft passages, etc. Due to the design of the hollow shaft 82, such variations in the intermediate shaft design and the associated variation in control logic can be implemented in a relatively simple manner and with minimal changes to the housing 22 or other components of the internal assembly 30.

[0037] With reference also to Fig. 12 and Fig. 13 illustrates an example configuration of current passages from the control assembly 32 through the housing 22. As also discussed above, variations in the control architecture for different configurations of the internal assembly 30 can be achieved by selectively drilling (or otherwise forming) different numbers and configurations of passages from the control assembly 32 through the housing 22. As in Fig. 12, for example, passages 220 and 222 may extend from the main portion 32a of the control assembly 32 through the housing 22 to the hydraulic intermediate shaft 82 (for example, they may have been drilled through the housing 22 prior to installation of the control assembly 32). These passages may accordingly carry control signals via the hollow shaft 82 to the power passages 226 and 228, respectively, within the intermediate shaft 222. Other passages (not shown) from the control assembly 32 through the housing 22 may also be provided, including passages that are in or out of plane with the passages 220 and 222. For example, an out-of-plane passage (not shown) may extend from the supplemental portion 32b of the assembly 32 (in Fig. 12 and Fig. 13 not shown) to the axial gap 94 (or another feature of the hollow shaft 82). Likewise, in certain embodiments, one or both of the passages 220 and 222 (or other passages (not shown)) may not be provided or may be differently configured to exclude or alter certain paths for control signals from the control assembly 32.

[0038] As in Fig.13, passage 230 may extend from the main portion 32a of the control assembly 32 through the housing 22 to the hydraulic inlet 44 (e.g., it may have been drilled through the housing 22 prior to installation of the control assembly 32). The passage 230 may accordingly supply control signals to the coupling device 56 via various known routing configurations extending from the inlet 44 to the device 56. Other passages (not shown) from the assembly 32 through the housing 22 may also be provided, including passages that are in or out of plane with the passage 230. Likewise, in certain embodiments, the passage 230 (or other passages (not shown)) may not be provided to preclude the illustrated path for control signals from the control assembly 32.

[0039] In light of the above discussion, it will be appreciated that various configurations of passages from the hydraulic control assembly 32 through the housing 22 may be provided, depending on the particular configuration of the internal assembly 30 (e.g., the particular intermediate shaft, gears, coupling devices, etc. included). However, it will be appreciated that while such modification of the housing 22 may enable implementation of particular control logic, the housing 22 would not need to be modified to easily accommodate the various components of the various configurations of the assembly 30. For example, in light of the above discussion, it will be appreciated that the hollow shaft 82 within the passage 28 may accommodate any of the intermediate shafts 62, 130, 150, or other intermediate shafts without requiring modification of the hollow shaft 82 or the housing 22.Subsequent (or prior) modification of the housing 22 to accommodate particular power control logic (e.g., drilling various passages from the control assembly 32 through the housing 22) may then be implemented as appropriate.

[0040] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a" and "an" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It is further understood that any use of the terms "comprises" and / or "comprising" herein specifies the presence of stated features, integers, steps, acts, and / or elements, but does not preclude the presence or addition of one or more features, integers, steps, acts, elements, components, and / or groups thereof.

Claims

[1] Modular powertrain assembly, comprising: an assembly housing (22) having first and second cavities (26, 24), the first and second cavities (26, 24) being connected by an intermediate cavity passage (28); a drive shaft (40) disposed at least partially within the first cavity (26) of the housing (22), the drive shaft (40) including a first gear (42) and receiving power from a power source; an output shaft (48) disposed at least partially within the first cavity (26) of the housing (22); a first clutch device (56) providing a controllable power transmission connection between the input shaft (40) and the output shaft (48); a hydraulic control assembly (32) providing hydraulic control signals for controlling, at least in part, power flow from the input shaft (40) to the output shaft (48); and a hydraulic control system that receives hydraulic control signals from the hydraulic control assembly (32) and directs the received hydraulic control signals to control, at least in part, power flow from the input shaft (40) to the output shaft (48); wherein a high-low power reversing intermediate shaft with second and third clutch devices (72, 74) includes a first gear connection to the first gear (42) of the input shaft (40), a second gear connection via the second clutch device (72) to the output shaft (48), and a third gear connection via the third clutch device (74) and a first idler gear to the output shaft (48); wherein a high-low intermediate shaft (130) with a fourth clutch device (138) includes a fourth gear connection to the first gear (42) of the input shaft (40) and a fifth gear connection via the fourth clutch device (138) to the output shaft (48); wherein a power reversing intermediate shaft (150) with a fifth clutch device (158) includes a sixth gear connection to the first gear (42) of the input shaft (40) and a seventh gear connection via the fifth clutch device (158) and a second idler gear to the output shaft (48); wherein the assembly housing (22) is configured to separately receive, without modification of the assembly housing (22), each of the high-low power reversing intermediate shaft, the high-low power reversing intermediate shaft (130), and the power reversing intermediate shaft (150); and wherein the hydraulic control system separately directs the received hydraulic control signals to at least one of the second and third clutch devices (72, 74), the fourth clutch device (138), or the fifth clutch device (158), depending on whether the high-low power reversing intermediate shaft, the high-low power reversing intermediate shaft (130), or the power reversing intermediate shaft (150) is currently received by the assembly housing (22). [2] The modular powertrain assembly of claim 1, wherein the hydraulic control system includes a hydraulic hollow shaft insert disposed at least partially within the intermediate cavity passage (28), the hydraulic hollow shaft insert including a plurality of control passages (104). [3] The modular powertrain assembly of claim 2, wherein the high-low power reversing intermediate shaft includes a first set of internal flow passages in communication with the second and third clutch devices (72, 74); wherein the high-low intermediate shaft (130) includes a second set of internal current passages in communication with the fourth clutch device (138); wherein the power reversing intermediate shaft (150) includes a third set of internal flow passages in communication with the fifth clutch device (158); and wherein the hydraulic hollow shaft insert directs the received hydraulic control signals separately and at least partially into the first set of internal flow passages, the second set of internal flow passages, or the third set of internal flow passages. [4] A modular powertrain assembly according to claim 2 or 3, wherein the hydraulic hollow shaft insert includes a cylindrical body, a mounting flange (84) and a plurality of hydraulic input features in hydraulic communication with the hydraulic control assembly (32); wherein the cylindrical body includes an internal bore for separately inserting first ends of the high-low power reversing intermediate shaft, the high-low intermediate shaft (130) and the power reversing intermediate shaft (150); and wherein the cylindrical body further includes a plurality of sets of control passages, each set of control passages extending from the internal bore to an associated hydraulic input feature included in the plurality of hydraulic input features, wherein hydraulic control signals from the hydraulic control assembly (32) are each passed separately from the hydraulic input features through the sets of control passages to the first, second and third sets of internal flow passages. [5] The modular powertrain assembly of claim 4, wherein the plurality of hydraulic input features includes a plurality of circumferential grooves separated by a plurality of seals; and wherein each set of control passages includes a plurality of control passages extending radially from the inner bore to the circumferential groove of the associated hydraulic input feature. [6] A modular powertrain assembly according to claim 4 or 5, wherein a bearing for at least one of the first ends of the high-low power reversing intermediate shaft, the high-low intermediate shaft (130) and the power reversing intermediate shaft (150) is seated against the cylindrical body within the intermediate cavity passage (28). [7] A modular drive train assembly according to any one of claims 4 to 6, wherein the inner bore is a blind bore having an end wall; and wherein, when the first ends of the high-low power reversing intermediate shaft (130), the high-low intermediate shaft (130), and the power reversing intermediate shaft (150) are separately inserted into the cylindrical bore, an axial gap remains between the respective first ends and the end wall, the axial gap being in fluid communication with a set of control passages included in the plurality of sets of control passages. [8] A hydraulic hollow shaft insert for conducting hydraulic control signals from a hydraulic control assembly (32) to various components contained within a housing (22), the hydraulic hollow shaft insert comprising: a cylindrical body with an internal bore; a mounting flange for attaching the cylindrical body to the housing (22); and a plurality of hydraulic input features in hydraulic communication with the hydraulic control assembly (32); and a plurality of sets of control passages, each set of control passages extending from the inner bore to an associated hydraulic input feature included in the plurality of hydraulic input features, wherein a hydraulic control signal is passed from the hydraulic control assembly (32) to a hydraulic input feature included in the plurality of hydraulic input features through an associated set of control passages included in the plurality of sets of control passages for controlling an associated device, wherein a high-low power reversing intermediate shaft having first and second clutch devices (56, 72) includes a first gear connection to a first gear (42) of an input shaft (40) contained in the housing (22), a second gear connection via the first clutch device (56) to an output shaft (48) contained in the housing (22), and a third gear connection via the second clutch device (72) and a first idler gear to the output shaft (48); wherein a high-low intermediate shaft (130) with a third clutch device (74) includes a fourth gear connection with the first gear (42) of the input shaft (40) and a fifth gear connection via the third clutch device (74) with the output shaft (48); wherein a power reversing intermediate shaft (150) with a fourth clutch device (138) includes a sixth gear connection with the first gear (42) of the input shaft (40) and a seventh gear connection via the fourth clutch device (138) and a second idler gear with the output shaft (48); wherein the inner bore is configured to separately receive, without modification of the inner bore, each of the high-low power reversing intermediate shaft, the high-low intermediate shaft (130) and the power reversing intermediate shaft (150); and wherein the hydraulic control signal is passed via the associated set of control passages to at least one of the first and second clutch devices (56, 72), the third clutch device (74), or the fourth clutch device (138), depending on whether the high-low power reversing intermediate shaft, the high-low intermediate shaft (130), or the power reversing intermediate shaft (150) is currently received by the inner bore, characterized by , that the high-low power reversing intermediate shaft includes a first set of internal flow passages in communication with the first and second clutch devices (56, 72); wherein the high-low intermediate shaft (130) includes a second set of internal current passages in communication with the third clutch device (74); wherein the power reversing intermediate shaft (150) includes a third set of internal flow passages in communication with the fourth clutch device (138); and wherein the hydraulic hollow shaft insert directs hydraulic control signals from the hydraulic control assembly (32) separately and at least partially into the first set of internal flow passages, the second set of internal flow passages, and the third set of internal flow passages, wherein the hydraulic hollow shaft insert directs the hydraulic control signals through one or more of the hydraulic input features and through one or more of the sets of control passages. [9] The hollow hydraulic shaft insert of claim 8, wherein the plurality of hydraulic input features includes a plurality of circumferential grooves separated by a plurality of seals; and wherein each set of control passages includes a plurality of control passages extending radially from the inner bore to the circumferential groove of the associated hydraulic input feature. [10] A hollow hydraulic shaft insert according to claim 9 or 10, wherein the housing (22) includes first and second cavities (26, 24) and an intercavity passage (28) extending between the first and second cavities; and wherein the cylindrical body is seated within the intercavity passage (28). [11] A hydraulic hollow shaft insert according to claim 10, wherein a bearing (54) for supporting an intermediate shaft inserted into the inner bore is set against the cylindrical body within the intermediate cavity passage (28).

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