1. An integrated modular end cover (100) for transfer case of four-wheel drive vehicle, the transfer case including a housing and at least three coaxially arranged shafts supported on tapered roller bearing set, the end cover (100) comprises: a body having an inner face configured to mate with the transfer case housing; a plurality of concentric axial contact faces (102) formed on the inner face of the end cover (100), each axial contact face (102) corresponding to an outer race of a respective tapered roller bearing set of the coaxial shafts, wherein the concentric axial contact faces (102) being machined to predetermined depths in a single machining operation such that, upon fastening of the end cover (100) to the housing, the axial contact faces (102) simultaneously axially lock the respective shafts, and generate controlled bearing preload on the tapered roller bearing sets; and at least one shim interface (104) provided between the end cover (100) and the housing for fine adjustment of preload, wherein axial locking and preload generation of multiple shafts are achieved through the end cover (100) as a single structural component.

2. The integrated modular end cover (100) as claimed in claim 1, wherein the end cover (100) further comprises an integrated bush stiffener (108) press-fitted into a hanger interface portion of the end cover (100), wherein bush stiffener (108) configured to locally increase stiffness at a gearbox mounting region, distribute hanger bracket loads into the body of the end cover (100), and support a hanger bracket having an elastomeric mounting element for vibration isolation.

3. The integrated modular end cover (100) as claimed in claim 1, wherein one or more internal oil galleries (106) are formed within the body of the end cover (100) by casting and/or machining, wherein the oil galleries (106) being configured to deliver lubricating oil directly to bearing interfaces of the coaxial shafts, and maintain lubrication under inclined and off-road operating conditions.

4. The integrated modular end cover (100) as claimed in claim 1, wherein sealing grooves and sealing surfaces are integrally formed in the end cover (100) to provide fluid sealing while maintaining axial locking and bearing preload integrity.

5. The integrated modular end cover (100) as claimed in claim 1, wherein the end cover (100) functions as a load-bearing structural member configured to support axial and radial loads of the transfer case shafts to improve stiffness and alignment of the transfer case assembly.

6. The integrated modular end cover (100) as claimed in claim 1, wherein consolidation of axial locking, preload generation, lubrication routing, sealing, and structural support into the single end cover (100) reduces cumulative dimensional tolerance stack-up within the transfer case assembly.

7. The integrated modular end cover (100) as claimed in claim 1, wherein the end cover (100) is configured for modular use across vehicle platforms of different gross vehicle weights including approximately 2.5-tonne and 7.5-tonne applications without increase in overall envelope dimensions of the transfer case.

8. A method of axially locking and preloading bearing sets of a transfer case of a four-wheel drive vehicle using an integrated modular end cover (100), the transfer case comprising a housing and at least three coaxially arranged shafts supported on tapered roller bearing sets, the method comprising the steps of: providing an end cover (100) having a body with an inner face and a plurality of concentric axial contact faces (102) corresponding respectively to outer races of the tapered roller bearing sets; machining the concentric axial contact faces (102) to predetermined depths in a single machining operation; positioning at least one shim between the end cover (100) and the transfer case housing for preload adjustment; aligning the end cover (100) with the housing such that each axial contact face (102) engages the corresponding outer race of the tapered roller bearing set; and fastening the end cover (100) to the housing, wherein fastening of the end cover (100) simultaneously axially locks the respective coaxial shafts, and generates controlled bearing preload on the tapered roller bearing sets

Description:AN INTEGRATED MODULAR END COVER FOR TRANSFER CASE OF FOUR-WHEEL DRIVE VEHICLE

FIELD OF THE DISCLOSURE
[0001] The present invention relates generally to the field automotive transmission systems, and more particularly to an integrated modular end cover for transfer case of four-wheel drive vehicle.
BACKGROUND OF THE INVENTION

[0002] The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
[0003] In current commercial vehicle gearbox platforms, end cover designs are generally limited in functionality and are predominantly utilized for basic retention purposes. In reverted gear train arrangements involving two coaxial shafts, conventional end covers primarily serve to lock bearing outer races and close the gearbox housing while providing shaft sealing. However, in auxiliary gearboxes and transfer cases incorporating single- or multi-speed reduction stages, the drivetrain architecture evolves into compound gear train configurations having three parallel or coaxial shafts. In such configurations, existing benchmark end cover designs continue to perform only limited roles, including shaft sealing, housing closure, and basic bearing retention, without addressing broader structural or functional requirements of the assembly.
[0004] To compensate for these limitations, additional components such as separate covers, brackets, or mounting structures are often employed to perform functions including shaft locking, bearing retention, and gearbox mounting or hanger support. This functionally segregated approach results in an increased number of components and mechanical interfaces, leading to greater tolerance stack-up that adversely affects bearing preload accuracy and assembly precision. Furthermore, structural stiffness at hanger mounting regions is often inadequate, and adaptability of end cover designs across different vehicular platforms remains limited. Consequently, conventional end covers have historically been underutilized, contributing minimally to structural load distribution, vibration isolation, or lubrication management within transfer case systems.
[0005] According to the patent application number “JPH07132905A” titled “Method of shutting case cover in transfer line and apparatus thereof” discloses a large quantity of covers in a simple structure when shutting the covers on case bodies, by preparing covers in the state that they are declined toward the front and transferring the case bodies horizontally to press the front end of case body at the opening end of cover and continuously moving the case bodies in the transferring direction. Case bodies 3 are transferred by a case body-supply conveyor 5 in the state that the upper opening end thereof is turned up. And covers 2 are transferred by a cover-supply conveyor 6 horizontally in the state that the lower end opening thereof is turned down and forced to wait at the terminal end of the conveyor 6 while keeping the slanting state. And the front end of the upper end opening of the case bodies 3 transferred horizontally is moved to press the front end of the lower end opening of the covers 2 which are waiting at a slant. And the cover 2 is put on the case body 3 by a certain extent. Thereafter, the case 4 in which the cover 2 is put on the case body 3 by a certain extent, is horizontally transferred by a converging conveyor 7 positioned on the stretched line of the case body-supply conveyor 5 to completely put the cover 2 on the case body 3. In this way, the case body 3 can be automatically shut by the cover 2 without manual operations.
[0006] According to the patent application number “JP2002012048A” titled “Transfer case for four-wheel drive vehicle” discloses a lubricating device for an endless chain in a transfer case for preventing the intrusion of air into lubricating oil and the agitation of the lubricating oil to prevent the temperature rise of the lubricating oil. SOLUTION: A casing 11 of the transfer case 10 for a four-wheel drive vehicle 1 is divided in two sections for isolating a fluid, i.e., a lubricating reservoir 14 for putting the adequate quantity of lubricant, and a torque transfer section 15 for keeping the stainless endless chain for transmitting torque. An oil pump assembly 50 is disposed in the lubricant reservoir 14 so as to supply the lubricant under pressure. A tubular lubricant dispensing member 58 connected to a pump discharge port extends from the lubricant reservoir to the torque transfer section so as to supply the endless chain 36 with the lubricant. The excess quantity of the lubricant is returned to the lubricant reservoir via a lubricant return port 16'. A lubricant catcher 18' is provided in the torque transfer section 15 to direct the excess lubricant toward the return port 16'.
[0007] The cited prior art references discloses an automated method and apparatus for shutting a case cover onto a case body, wherein the cover functions merely as a closure component within an assembly line process and does not address structural or functional enhancement of the cover itself, particularly lacking disclosure of axial shaft locking, direct bearing preload generation through precision-machined axial faces, structural load support, or integrated lubrication features within a transfer case environment. Further, the patent application discloses a transfer case lubrication system employing segregated reservoir sections, pump assemblies, and lubricant dispensing members for chain lubrication, thereby maintaining a functionally segregated architecture without integration of lubrication management into an end cover structure or consolidation of multiple drivetrain-support functions. Consequently, the prior art fails to teach or suggest an integrated modular end cover capable of simultaneously performing shaft locking, bearing preload generation, sealing, structural reinforcement, and lubrication routing while reducing component count, minimizing tolerance stack-up, and enabling adaptability across different vehicular platforms, as achieved by the present invention.
OBJECTIVES OF THE INVENTION
[0008] An objective of the invention is to provide an integrated modular end cover for transfer case of four-wheel drive vehicle.
[0009] Furthermore, the objective of the invention is to provide a method of axially locking and preloading bearing sets of a transfer case of a four-wheel drive vehicle using an integrated modular end cover.
[0010] An objective of the invention is to provide an integrated modular end cover for a transfer case of a four-wheel drive vehicle that overcomes the limitations of conventional end covers by consolidating multiple functional roles into single structural components.
[0011] Furthermore, the objective of invention is to provide the end cover configured to axially lock multiple coaxial shafts and generate controlled preload on tapered roller bearing sets through precision-machined concentric axial contact faces.
[0012] Furthermore, the objective of the present invention is to provide the end cover that acts as a load-bearing structural member capable of distributing axial and radial loads and improving stiffness and alignment within the transfer case assembly.
[0013] Furthermore, the objective of the present invention is to provide the end cover incorporating integrated lubrication passages for directing lubricant to critical bearing interfaces under varying operating conditions
SUMMARY
[0014] The present invention relates to an integrated modular end cover for transfer case of four-wheel drive vehicle.
[0015] According to an aspect, an integrated modular end cover for transfer case of four-wheel drive vehicle. Further, the transfer case including a housing and at least three coaxially arranged shafts supported on tapered roller bearing set, the end cover comprises a body having an inner face configured to mate with the transfer case housing. Further, a plurality of concentric axial contact faces formed on the inner face of the end cover, each axial contact face corresponding to an outer race of a respective tapered roller bearing set of the coaxial shafts. Further, the concentric axial contact faces being machined to predetermined depths in a single machining operation such that, upon fastening of the end cover to the housing, the axial contact faces simultaneously axially lock the respective shafts, and generate controlled bearing preload on the tapered roller bearing sets. Further, at least one shim interface provided between the end cover and the housing for fine adjustment of preload. Further, axial locking and preload generation of multiple shafts are achieved through the end cover as a single structural component.
[0016] According to an another aspect, a method of axially locking and preloading bearing sets of a transfer case of a four-wheel drive vehicle using an integrated modular end cover, the transfer case comprising a housing and at least three coaxially arranged shafts supported on tapered roller bearing sets. Further, the method comprising the steps of providing an end cover having a body with an inner face and a plurality of concentric axial contact faces corresponding respectively to outer races of the tapered roller bearing sets. Further, machining the concentric axial contact faces to predetermined depths in a single machining operation. Further, positioning at least one shim between the end cover and the transfer case housing for preload adjustment. Further, aligning the end cover with the housing such that each axial contact face engages the corresponding outer race of the tapered roller bearing set. Further, fastening the end cover to the housing, wherein fastening of the end cover simultaneously axially locks the respective coaxial shafts, and generates controlled bearing preload on the tapered roller bearing sets.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The accompanying drawings illustrate the embodiment of the system. Any person with ordinary skills in the art will appreciate that the illustrated element boundaries (e.g., boxes, groups of boxes, or other shapes) in the figures represent one example of the boundaries. It may be that in some examples one element may be designed as multiple elements or that multiple elements may be designed as one element. In some examples, an element shown as an internal component of one element may be implemented as an external component in another, and vice versa. Furthermore, elements may not be drawn to scale. Non-limiting and non-exhaustive descriptions are described with reference to the following drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating principles.
[0018] FIG. 1 illustrates an isometric view of an integrated modular end cover for transfer case of four-wheel drive vehicle, according to an embodiment of the present invention.
[0019] FIG. 2 illustrates a side view of an integrated modular end cover for transfer case of four-wheel drive vehicle, according to an embodiment of the present invention.
[0020] FIG. 3 illustrates an oil Gallery Provision for the lubrication through natural capillarity action of the integrated modular end cover for transfer case of four-wheel drive vehicle, according to an embodiment of the present invention.
[0021] FIG. 4 illustrates a flow chart of a method of axially locking and preloading bearing sets of a transfer case of a four-wheel drive vehicle using an integrated modular end cover, according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[0022] Some embodiments of this disclosure, illustrating all its features, will now be discussed in detail. The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items or meant to be limited to only the listed item or items. It must also be noted that as used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
[0023] Although any systems and methods similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present disclosure, the preferred, systems and methods are now described. Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings in which like numerals represent like elements throughout the several figures, and in which example embodiments are shown. Embodiments of the claims may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The examples set forth herein are non-limiting examples and are merely examples among other possible examples.
[0024] The present invention discloses an integrated modular end cover for transfer case of four-wheel drive vehicle.
[0025] FIG. 1 illustrates an isometric view of an integrated modular end cover (100) for transfer case of four-wheel drive vehicle, according to an embodiment of the present invention. FIG. 2 illustrates a side view of an integrated modular end cover (100) for transfer case of four-wheel drive vehicle, according to an embodiment of the present invention. FIG. 3 illustrates an oil gallery provision for the lubrication through natural capillarity action of the integrated modular end cover (100) for transfer case of four-wheel drive vehicle, according to an embodiment of the present invention.
[0026] In some embodiments, the integrated modular end cover (100) comprises a housing and at least three coaxially arranged shafts supported on tapered roller bearing set, a body, a plurality of concentric axial contact faces (102), at least one shim interface (104), and one or more internal oil galleries (106) are formed within the body of the end cover (100), the end cover (100) further comprises an integrated bush stiffener (108) press-fitted into a hanger interface portion of the end cover (100).
[0027] In some embodiments, the integrated modular end cover (100) for the transfer case of the four-wheel drive vehicle refers to a structurally unified cover component designed to interface with the transfer case housing that contains at least three coaxially arranged shafts supported on tapered roller bearing sets. Unlike conventional covers serving only sealing or closure functions, the integrated modular end cover (100) is configured with precision-machined internal features that engage bearing outer races to axially locate the shafts and generate controlled bearing preload upon fastening to the housing. The modular nature of the design allows the same cover architecture to be adapted across different vehicular platforms and torque capacities, while simultaneously providing structural load support, sealing interfaces, and lubrication management within a single component. By consolidating multiple mechanical and functional roles into one integrated element, the end cover (100) improves assembly accuracy, reduces component count and tolerance accumulation, enhances stiffness and reliability of the transfer case assembly, and enables efficient packaging within the drivetrain system.
[0028] In some embodiments, the end cover (100) comprises the body having an inner face configured to mate with the transfer case housing. The body of the integrated modular end cover (100) includes the inner face configured to mate with a corresponding mounting surface of the transfer case housing. The end cover (100) functions as a load-bearing structural member configured to support axial and radial loads of the transfer case shafts to improve stiffness and alignment of the transfer case assembly. This inner face is machined to predetermined dimensional tolerances to ensure precise alignment with the housing interface to establish accurate positioning of the end cover (100) relative to the coaxial shafts and bearing sets. The mating configuration may include bolt holes, dowel locations, sealing grooves, and contact surfaces that collectively ensure structural rigidity, fluid sealing, and controlled axial positioning when the cover is fastened to the housing.
[0029] In some embodiments, the plurality of concentric axial contact faces (102) is formed on the inner face of the end cover (100) as annular, stepped surfaces arranged about a common axis, each surface being dimensioned and positioned to correspond with the outer race of a respective tapered roller bearing set supporting the coaxial shafts. The contact faces (102) are precisely machined to predetermined axial locations so that, when the end cover (100) is assembled to the transfer case housing, each face comes into controlled abutting engagement with its corresponding bearing outer race. Such engagement ensures accurate axial positioning of the bearing sets and associated shafts, facilitates uniform load transfer across the bearing interfaces, and enables simultaneous interaction with multiple bearing locations within a compact geometry. The concentric arrangement allows coordinated control of shaft alignment and mechanical stability within the transfer case while supporting the integrated functional role of the end cover (100) in locking and preload generation.
[0030] In some embodiments, the concentric axial contact faces (102) being machined to predetermined depths in a single machining operation such that, upon fastening of the end cover (100) to the housing, the axial contact faces (102) simultaneously axially lock the respective shafts, and generate controlled bearing preload on the tapered roller bearing sets. The concentric axial contact faces (102) are machined to predetermined axial depths in the single machining operation so as to maintain precise relative dimensional control between the multiple bearing engagement surfaces. By performing the machining in one setup, variation between individual contact faces (102) is minimized to reduce tolerance stack-up and ensuring consistent axial positioning. When the end cover (100) is fastened to the transfer case housing, these accurately machined faces abut against the respective bearing outer races to simultaneously restricting axial movement of the coaxial shafts and generating a controlled compressive load on the tapered roller bearing sets. The controlled compression establishes the required bearing preload without the need for separate preload-adjusting components for each shaft, resulting in improved alignment accuracy, enhanced load distribution, and reliable operational performance of the transfer case assembly.
[0031] In some embodiments, at least one shim interface (104) provided between the end cover (100) and the housing for fine adjustment of preload. The at least one shim interface (104) positioned at the mating interface, may be selected in varying thicknesses to achieve precise control over the axial spacing between the end cover (100) and the housing. By altering the effective stand-off distance, the compressive force transmitted through the concentric axial contact faces (102) to the bearing outer races may be incrementally increased or decreased.
[0032] In some embodiments, the axial locking and preload generation of multiple shafts are achieved through the end cover (100) as a single structural component. The axial locking and preload generation of multiple shafts are achieved through the end cover (100) as a single structural component by virtue of its integrally machined concentric axial contact faces (102) that simultaneously engage the respective bearing outer races upon assembly. Instead of employing separate locking plates, spacers, retainers, or independent preload mechanisms for each shaft, the end cover (100) itself performs the combined function of axially restraining the shafts and applying the required compressive force to the tapered roller bearings. When fastened to the housing, the cover transmits controlled axial loads uniformly across multiple bearing interfaces, thereby maintaining shaft positioning and ensuring consistent preload conditions. This unified structural approach reduces component count, simplifies assembly, minimizes tolerance accumulation, and enhances overall rigidity and reliability of the transfer case assembly.
[0033] In some embodiments, the end cover (100) further comprises an integrated bush stiffener (108) press-fitted into a hanger interface portion of the end cover (100). Further, the bush stiffener (108) being configured to reinforce the local structural region where the gearbox mounting loads are introduced. By being securely press-fitted, the bush stiffener (108) increases localized stiffness and reduces deformation under operational loads to enable efficient distribution of hanger bracket forces into the main body of the end cover (100). This structural reinforcement improves load transfer characteristics and reduces stress concentration at the mounting interface. Additionally, the bush stiffener (108) provides a stable support interface for a hanger bracket incorporating an elastomeric mounting element, which facilitates vibration isolation by damping transmitted oscillations from the drivetrain to the vehicle structure, thereby enhancing durability, noise reduction, and overall operational stability of the transfer case assembly.
[0034] In some embodiments, one or more internal oil galleries (106) are formed within the body of the end cover (100) through casting and/or subsequent machining operations, creating defined internal passageways for controlled lubricant flow. The oil galleries (106) are strategically positioned to communicate with the bearing interfaces of the coaxial shafts so that lubricating oil is delivered directly to the tapered roller bearing contact regions during operation. The internal routing ensures a continuous and targeted supply of lubricant, reducing reliance on splash lubrication alone. Additionally, the configuration of the galleries is configured to retain and guide oil even when the vehicle operates under inclined, off-road, or uneven terrain conditions, thereby preventing lubrication starvation, reducing frictional heat generation, and enhancing bearing life and thermal performance within the transfer case assembly.
[0035] In some embodiments, sealing grooves and sealing surfaces are integrally formed within the end cover (100) as part of its unitary structure to ensure effective containment of lubricating fluid within the transfer case assembly. The features are machined or cast into the mating and shaft-interface regions to accommodate sealing elements such as O-rings, gaskets, or radial seals, thereby preventing leakage while the cover is fastened to the housing. The integral formation ensures that sealing functionality is achieved without introducing separate components that may interfere with the axial positioning surfaces responsible for shaft locking and bearing preload generation. As a result, fluid sealing is maintained concurrently with precise axial load transfer through the concentric contact faces (102), preserving preload integrity, ensuring lubrication retention, and supporting reliable long-term operation of the drivetrain system.
[0036] In some embodiments, the consolidation of axial locking, bearing preload generation, lubrication routing, sealing, and structural support into a single integrated end cover (100) minimizes the number of separate components and mechanical interfaces within the transfer case assembly reduce cumulative dimensional tolerance stack-up. In conventional arrangements, each function is performed by independent parts such as retainers, spacers, brackets, and sealing members, and the dimensional variation of each interface contributes to overall assembly inaccuracy. By integrating these functions into a unitary component manufactured under controlled machining conditions, the relative spatial relationships between functional surfaces are maintained with higher precision. This reduces alignment errors, improves consistency of bearing preload and shaft positioning, enhances assembly repeatability, and ultimately leads to improved reliability, durability, and performance of the transfer case system.
[0037] In some embodiments, the end cover (100) is configured with a modular architecture that allows it to be implemented across vehicle platforms having different gross vehicle weight ratings, including approximately 2.5-tonne and 7.5-tonne applications, without requiring changes to the overall external envelope of the transfer case. This is achieved by designing the structural geometry, mounting interfaces, and functional features of the cover to accommodate variations in load and torque requirements through internal dimensional control, material selection, or localized reinforcement rather than external size modification. As a result, the same cover footprint may interface with different drivetrain configurations and gearbox ratings, enabling platform scalability while preserving packaging constraints. This modular adaptability reduces redesign effort, simplifies manufacturing and inventory management, and supports cost-effective deployment across multiple vehicle classes.
[0038] FIG. 4 illustrates a flow chart of a method (400) of axially locking and preloading bearing sets of a transfer case of a four-wheel drive vehicle using an integrated modular end cover (100), according to an embodiment of the present invention.
[0039] At operation 402, providing an end cover (100) having a body with an inner face and a plurality of concentric axial contact faces (102) corresponding respectively to outer races of the tapered roller bearing sets. The inner face of the body is configured as the mounting surface for alignment and fastening with the housing, while the concentric axial contact faces (102) are formed as annular, stepped engagement surfaces positioned about a common axis to match the spatial locations of the bearing outer races. The configuration ensures that, upon assembly, each contact face (102) can interact directly with its corresponding bearing interface, enabling coordinated positioning, load transmission, and functional interaction across multiple shaft supports within the transfer case system.
[0040] At operation 404, machining the concentric axial contact faces (102) to predetermined depths in a single machining operation. By performing the machining in a single operation such as a single clamping and tool-setting sequence the dimensional relationship between the multiple contact faces (102) is established with high accuracy, minimizing inter-surface variation and eliminating cumulative alignment errors that could arise from multiple machining stages.
[0041] At operation 406, positioning at least one shim interface (104) between the end cover (100) and the transfer case housing for preload adjustment involves placing a calibrated spacer element of selected thickness at the mating interface prior to fastening the cover. The shim acts as a controllable intermediary layer that alters the effective axial distance between the end cover (100) and the housing, thereby influencing the compressive load transmitted through the concentric axial contact faces (102) to the tapered roller bearing outer races. By selecting or varying the shim thickness during assembly, fine tuning of the bearing preload may be achieved to compensate for manufacturing tolerances and ensure optimal shaft positioning and bearing performance.
[0042] At operation 408, aligning the end cover (100) with the housing such that each axial contact face (102) engages the corresponding outer race of the tapered roller bearing set involves positioning the end cover (100) relative to the transfer case housing in a manner that ensures concentric and axial correspondence between the machined contact faces (102) and the respective bearing outer races. This alignment may be facilitated by dowel pins, bolt holes, pilot diameters, or locating features provided on the mating surfaces. Proper alignment ensures that, upon fastening, each axial contact face (102) comes into uniform and direct abutting engagement with its designated bearing interface without misalignment or uneven loading.
[0043] At operation 410, fastening the end cover (100) to the housing involves securing the end cover (100) onto the transfer case housing using suitable fastening elements such as bolts or screws so that the inner face of the cover is drawn into firm contact with the mating surface of the housing. As the fastening elements are tightened, the end cover (100) is axially displaced toward the housing, causing the concentric axial contact faces (102) to press against the corresponding outer races of the tapered roller bearing sets. This engagement simultaneously restricts axial movement of the coaxial shafts, thereby locking them in position, and applies a controlled compressive force to the bearing assemblies to establish the desired preload condition.
[0044] It has thus been seen the integrated modular end cover (100) for transfer case of four-wheel drive vehicle as described. The integrated modular end cover (100) for transfer case of four-wheel drive vehicle in any case could undergo numerous modifications and variants, all of which are covered by the same innovative concept; moreover, all of the details can be replaced by technically equivalent elements. In practice, the components used, as well as the numbers, shapes, and sizes of the components can be whatever according to the technical requirements. The scope of protection of the invention is therefore defined by the attached claims
, Claims:I/We claim,
1. An integrated modular end cover (100) for transfer case of four-wheel drive vehicle, the transfer case including a housing and at least three coaxially arranged shafts supported on tapered roller bearing set, the end cover (100) comprises:
a body having an inner face configured to mate with the transfer case housing;
a plurality of concentric axial contact faces (102) formed on the inner face of the end cover (100), each axial contact face (102) corresponding to an outer race of a respective tapered roller bearing set of the coaxial shafts,
wherein the concentric axial contact faces (102) being machined to predetermined depths in a single machining operation such that, upon fastening of the end cover (100) to the housing, the axial contact faces (102) simultaneously axially lock the respective shafts, and generate controlled bearing preload on the tapered roller bearing sets; and
at least one shim interface (104) provided between the end cover (100) and the housing for fine adjustment of preload,
wherein axial locking and preload generation of multiple shafts are achieved through the end cover (100) as a single structural component.
2. The integrated modular end cover (100) as claimed in claim 1, wherein the end cover (100) further comprises an integrated bush stiffener (108) press-fitted into a hanger interface portion of the end cover (100), wherein bush stiffener (108) configured to locally increase stiffness at a gearbox mounting region, distribute hanger bracket loads into the body of the end cover (100), and support a hanger bracket having an elastomeric mounting element for vibration isolation.
3. The integrated modular end cover (100) as claimed in claim 1, wherein one or more internal oil galleries (106) are formed within the body of the end cover (100) by casting and/or machining, wherein the oil galleries (106) being configured to deliver lubricating oil directly to bearing interfaces of the coaxial shafts, and maintain lubrication under inclined and off-road operating conditions.
4. The integrated modular end cover (100) as claimed in claim 1, wherein sealing grooves and sealing surfaces are integrally formed in the end cover (100) to provide fluid sealing while maintaining axial locking and bearing preload integrity.
5. The integrated modular end cover (100) as claimed in claim 1, wherein the end cover (100) functions as a load-bearing structural member configured to support axial and radial loads of the transfer case shafts to improve stiffness and alignment of the transfer case assembly.
6. The integrated modular end cover (100) as claimed in claim 1, wherein consolidation of axial locking, preload generation, lubrication routing, sealing, and structural support into the single end cover (100) reduces cumulative dimensional tolerance stack-up within the transfer case assembly.
7. The integrated modular end cover (100) as claimed in claim 1, wherein the end cover (100) is configured for modular use across vehicle platforms of different gross vehicle weights including approximately 2.5-tonne and 7.5-tonne applications without increase in overall envelope dimensions of the transfer case.
8. A method of axially locking and preloading bearing sets of a transfer case of a four-wheel drive vehicle using an integrated modular end cover (100), the transfer case comprising a housing and at least three coaxially arranged shafts supported on tapered roller bearing sets, the method comprising the steps of:
providing an end cover (100) having a body with an inner face and a plurality of concentric axial contact faces (102) corresponding respectively to outer races of the tapered roller bearing sets;
machining the concentric axial contact faces (102) to predetermined depths in a single machining operation;
positioning at least one shim between the end cover (100) and the transfer case housing for preload adjustment;
aligning the end cover (100) with the housing such that each axial contact face (102) engages the corresponding outer race of the tapered roller bearing set; and
fastening the end cover (100) to the housing, wherein fastening of the end cover (100) simultaneously axially locks the respective coaxial shafts, and generates controlled bearing preload on the tapered roller bearing sets