US20080257885A1

US20080257885A1 - Access port clamp cover

Info

Publication number: US20080257885A1
Application number: US11/788,534
Authority: US
Inventors: Loren Christopher Dreier
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2007-04-20
Filing date: 2007-04-20
Publication date: 2008-10-23

Abstract

An access port clamp cover is disclosed, such as for access ports in housings of motor vehicle driveline components. An access port clamp cover includes a first cover having a centrally disposed cylindrical member defining at least one locking slot in its outer surface and a handle extending from the cylindrical member. The access port clamp cover also includes a second cover defining a centrally disposed retaining member having an opening for receiving the handle and an annulus concentrically disposed about the opening. The annulus defines an inside diameter larger than an outside diameter of the cylindrical member and has at least one protrusion extending radially inwardly from the inside surface. Also, the protrusion is engageable in the slot, and the covers may be rotated relative to one another.

Description

FIELD OF THE INVENTION

The invention relates generally to covers for access ports in housings of motor vehicle driveline components such as transmissions, clutches, and differentials and more specifically to an access port clamp cover having inner and outer plates that include cooperating twist and lock retaining components.

BACKGROUND OF THE INVENTION

Modern vehicular driveline devices, such as clutches, transmissions, and differentials have as one of their many design goals increased service life. Such service life goals are often subdivided into a first goal of increasing the service interval, that is, the time between any required maintenance and a second goal of absolute service life, that is, the total life of the component typically measured in hundreds of thousands of miles.
Because such a device may reside in the power train of a vehicle for years before it is replaced, providing access to the interior of the device for preventative or minor maintenance without requiring removal of the device from the vehicle is desirable. Additionally, it is desirable that such access means be readily and easily removable so that inspection or minor service may be quickly accomplished. Finally, it may also be desirable that any such access means provide a secure, leak proof seal which can be maintained during any and all anticipated operating conditions and environment.
U.S. Pat. No. 1,581,928 teaches a cover for a transmission of a motor vehicle in which a small, readily removable cover is located in a cutout of a larger access plate which is removable only with hand tools.
U.S. Pat. No. 2,703,663 teaches a closure plate holding means wherein a bolt secured cover may be removed to provide access into the interior, water jacket region of an internal combustion engine.
Study of the foregoing patents reveals that improvements in access panel art are desirable.

BRIEF SUMMARY

According to one aspect of an access port clamp cover, a first cover has a centrally disposed cylindrical member defining at least one locking slot in its outer surface and a handle extending from the cylindrical member. The access port clamp cover also includes a second cover defining a centrally disposed retaining member having an opening for receiving the handle and an annulus concentrically disposed about the opening. The annulus defines an inside diameter larger than an outside diameter of the cylindrical member and has at least one protrusion extending radially inwardly from the inside surface. Also, the protrusion is engageable in the slot, and the covers may be rotated relative to one another.
Other systems, methods, features and advantages of the access port cover will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description.

BRIEF DESCRIPTION OF THE DRAWINGS

The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.

FIG. 1 is a side elevational view of a portion of a motor vehicle driveline incorporating an access port clamp cover according to a first exemplary embodiment.

FIG. 2 is a sectional view of an access port clamp cover according to the first exemplary embodiment taken along line 2-2 of FIG. 1.

FIG. 3 is an exploded, sectional view of an access port clamp cover according to the first exemplary embodiment.

FIG. 4 is a plan view of an inside clamp cover according to the first exemplary embodiment taken along line 4-4 of FIG. 3.

FIG. 5 is a sectional view of a second exemplary embodiment of an access port clamp cover.

FIGS. 6A and 6B illustrate the installation and removal process of an access port clamp cover.

FIG. 7 is a fragmentary, sectional view of a third exemplary embodiment of an access port clamp cover.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

Referring now to FIG. 1, a portion of a motor vehicle driveline is illustrated. The motor vehicle driveline portion includes an internal combustion engine 12 that provides motive power to a master clutch 14, which may be activated and deactivated to provide such motive power to a multiple speed transmission 16. The transmission 16 may be either a manual, automated manual, or automatic transmission and thus may include a shift operator assembly 18 or a shift lever (not illustrated). That transmission 16 includes an output feature such as a shaft or U-joint 20 which is coupled to and drives a prop shaft, differential, and/or axles (all not illustrated). The transmission 16 typically will include a cast metal housing 22 which receives, supports, positions and protects the various internal and external components and will typically include oil drain and fill plugs 24 and 26 to facilitate changing the lubricating oil within the transmission 16.
Referring now to FIGS. 2 and 3, an access port clamp cover assembly 30 according to a first exemplary embodiment is illustrated in place on an access opening or port 32 in the sidewall of the metal housing 22. If desired, the inside surface of the housing 22 may include two or more lugs or bosses 34, or a continuous lip or flange (not illustrated) to assist locating the cover assembly 30. Alternatively, the access opening or port 32 may be on any component of the motor vehicle driveline. For example, the access opening or port 32 may be on the internal combustion engine 12 or a clutch housing encompassing the master clutch 14.
The clamp cover assembly 30 includes a first or inner plate or cover 36 having height and width which are somewhat larger than the corresponding height and width of the access port 32. Additionally, the first plate or cover 36 is preferably, though not necessarily, slightly convex. About the periphery of the first plate or cover 36 may be disposed a continuous peripheral shallow groove or channel 38 that receives a continuous resilient O-ring seal 42. The O-ring seal 42 may be fabricated of an elastomer or other resilient material that is compatible with the lubricating oil utilized within the transmission 16. At the center of the first plate or cover 36 is a securement assembly 44 having a short cylindrical member 46 concentrically disposed about a smaller diameter, elongate stub shaft or handle 48.
On the outer surface of the cylindrical member 46 are locking channel(s) or slot(s) 52, such as, for example, a pair of diametrically opposed J-shaped or L-shaped channels or slots, one of which is illustrated in FIGS. 2 and 3. The channel(s) or slot(s) 52 have a first axial portion 54 that is open and commences at the end surface of the cylindrical member 46, an arcuate, circumferential portion 56, which communicates with the first axial portion 54 and a short reentrant terminal portion 58 extending axially away from the plate or cover 36. The stub shaft or handle 48 is sufficiently long to extend beyond the outside surface of the housing 22 when the first plate or cover 36 is located as illustrated in FIG. 2 and may include surface treatment such as knurling 62 or other features to improve its gripability.
Aligned with the first inside plate or cover 36 is a second, outer plate or cover 66 that also has dimensions slightly larger than the dimensions of the access opening or port 32. Likewise, the outer plate or cover 66 is preferably slightly, though not necessarily, convex. The outer plate or cover 66 may also include a continuous peripheral shallow groove or channel 68 that receives a resilient sealing member such as an O-ring 72. Centrally disposed within the second, outer cover or plate 66 and aligned with the securement assembly 44 is an annular retaining assembly 74. The annular retaining assembly 74 includes an annular or tubular member 76 including an inside cylindrical surface 78 having an inside diameter just slightly larger than the outside diameter of the cylindrical member 46. Extending inwardly from the inside cylindrical surface 78 of the tubular member 76 is a protrusion, pin, or lug 82. Alternatively, multiple protrusions, pins, or lugs 82 may be used, such as, for example, a pair of protrusions, pins, or lugs, one of which is illustrated in FIGS. 2 and 3. The protrusion, pin, or lug 82 is complementary to and engages the locking slot 52 and cooperates therewith to provide a twist and lock, i.e., bayonet, mounting connection between the first and second covers 36 and 66. It will be appreciated that while a single locking slot 52 and cooperating protrusion, pin, or lug 82 will provide the desired twist and lock assembly feature, two cooperating slots 52 and two protrusions, pins, or lugs 82 are preferred and three, four or more cooperating slots 52 and protrusions, pins, or lugs 82 may be utilized if desired. The retaining assembly 74 also defines a through aperture or passageway 86 that facilitates free passage of the stub shaft or handle 48 through the retaining assembly 74.
Alternatively, one or multiple protrusion(s), pin(s), or lug(s) 82 may extend outwardly from the cylindrical member 46, and one or multiple locking channel(s) or slot(s) 52 may be on the inside cylindrical surface 78 of the tubular member 76. Protrusion(s), pin(s), or lug(s) 82 and locking channel(s) or slot(s) 52 may be mixed and matched in any combination or position on covers 36 and 66.
Some components of the clamp cover assembly 30, for example, but not limited to, the resilient seal, such as O-ring 42 and/or O-ring 72, and/or the first plate or cover 36, and/or the second plate or cover 66, may elastically deform during installation while locking the slots. This elastic deformation may provide a clamp load, thereby ensuring a tight fit over the access port 32. Therefore, the clamp cover assembly 30 remains firmly set even during vibrations or other occurrences causing disruptive motions.
Referring now to FIG. 4, the second or outer plate or cover 66 is illustrated in a plan view. Here, the peripheral channel 68 is shown below the resilient O-ring seal 72 and the retaining assembly 74 including the tubular member 76, the inside cylindrical surface 78, the diametrically opposed pair of pins or lugs 82, and the through opening 86.
Referring now to FIG. 5, a second exemplary embodiment of an access port clamp cover is illustrated and designated by the reference number 90. Here, the first or inside plate or cover 36′ is the same as the first exemplary embodiment of the inner access port cover 36 except it does not include the peripheral groove 38 and the resilient O-ring seal 42. Thus, the inner seal between the inner access plate or cover 36′ will typically not be fluid tight. However, the second, outer plate or cover 66 will typically include the resilient O-ring seal 72. It will be appreciated, of course, that a further alternative construction comprehends utilizing a peripheral groove 38 and O-ring seal 42 on the first plate or cover 36 as illustrated in FIGS. 2 and 3 but omitting the peripheral groove 68 and O-ring seal 72 on the second, outer plate or cover 66. A second modification utilized in the access port clamp cover assembly 90 involves replacing the knurling 62 on the stub shaft or handle 48 with a circumferential concave region 92 which may, under certain circumstances provide better grip of the handle 48. Additionally, it may be desirable to provide a transverse through opening 94 in the handle 48 near the retaining assembly 74 to ensure that the covers or plates 36′ and 66 remain on the housing 22. This is achieved by inserting a spring retaining clip or cotter pin 96 through the transfer aperture 94 in the handle 48. Alternatively, the pin 96 may be a fastener or snap ring and the transfer aperture 94 may be a hole or groove, respectively.
Reference to FIGS. 6A and 6B provides an illustration of the installation procedure of an access port clamp cover 30. The first or inner plate or cover 36 is positioned with its narrow dimension parallel to the long dimension of the access opening or port 32. The first cover 36 is then inserted into the access port 32 and rotated 90° until it is in the position illustrated in FIG. 6B. The handle 48 may now be held while the second or outer plate or cover 66 is installed and rotated to engage the protrusions, pins, or lugs 82 in the reentrant, terminal portions 58 of the slots 52. It will be appreciated that installation is facilitated if the region of the housing 22 proximate the access port 32 is flat. Alternatively, the region of the housing 22 proximate the access port 32 may be curved or any other geometrical shape.
FIG. 7 illustrates a third exemplary embodiment of an access port clamp cover assembly 100. Access port 102 is oval and thus the access port plates or covers are likewise oval. Here, the inside cover or plate 104 is in position within the oval access port 102. This illustration is presented to note once again that the access port or openings 32 or 102 preferably will define a longer or major dimension and a shorter or minor dimension such that the inside plate or cover 36, 36′ or 104 may be inserted with its minor dimension parallel to the major dimension and then rotated approximately 90°.
It will be appreciated, however, that depending upon internal clearances and interferences, a square access port or opening may be utilized with a square inside cover inasmuch as the diagonal of a square is 1.414 times an edge of the square which theoretically, at least, provides sufficient clearance to pass the inside cover or plate through the access port and move and rotate it in proper alignment with the access port or opening. Thus, while rectangular or oblong or oval access port shapes are preferable, this is not a limitation on the access port and cover shapes.
It should also be appreciated, of course, that the locations of the cylindrical member 46 and locking slot 52 on the first or inner cover or plate 36 and the tubular member 76 and protrusion, pin, or lug 82 on the second or outside cover or plate 66 may be interchanged.
The foregoing disclosure is the best mode devised by the inventor for practicing this invention. It is apparent, however, that apparatus incorporating modifications and variations will be obvious to one skilled in the art of covers for access ports in the housings of motor vehicle driveline components. Inasmuch as the foregoing disclosure is intended to enable one skilled in the pertinent art to practice the present invention, it should not be construed to be limited thereby but should be construed to include such aforementioned obvious variations and be limited only by the spirit and scope of the following claims.

Claims

1. An access port clamp cover assembly, comprising:

a first cover having a centrally disposed cylindrical member defining at least one locking slot in its outer surface and a handle extending from said cylindrical member;

a second cover defining a centrally disposed retaining member having an opening for receiving said handle and an annulus concentrically disposed about said opening, said annulus defining an inside diameter larger than an outside diameter of said cylindrical member and having at least one protrusion extending radially inwardly from said inside surface;

whereby said protrusion is engageable in said slot and said covers may be rotated relative to one another.

2. The access port clamp cover assembly of claim 1 wherein said cylindrical member includes at least two opposed slots and said retaining member includes at least two diametrically opposed protrusions.

3. The access port clamp cover assembly of claim 1 further including a seal receiving groove extending about and proximate a periphery of each of said covers and a resilient seal disposed in each of said seal receiving grooves.

4. The access port clamp cover assembly of claim 3 wherein said resilient seal is operable to elastically deform to provide a clamp load.

5. The access port clamp cover assembly of claim 1 further including at least one of a through opening and groove in said handle and at least one of a retaining pin, fastener, and snap ring operable to engage at least one of said through opening and groove.

6. The access port clamp cover assembly of claim 1 wherein at least one of said first cover and said second cover is operable to elastically deform to provide a clamp load.

7. The access port clamp cover assembly of claim 1 further including a housing having an access port and at least one cover positioning feature disposed adjacent said access port.

8. An access port clamp cover for a driveline component housing, comprising:

a first cover having a handle extending therefrom, a cylinder having an outside surface coaxially disposed about said handle, said outside surface defining at least one slot having an axial entrance portion, a generally circumferential portion and terminal portion;

a second cover having an annular member defining an interior surface having a diameter larger than a diameter of said cylinder and at least one protrusion extending radially inwardly from said interior surface, said second cover also defining a through opening for receiving said handle of said first cover.

9. The access port clamp cover of claim 8 wherein said handle comprises a stub shaft.

10. The access port clamp cover of claim 8 wherein said cylindrical member includes at least two opposed locking slots and said annular member includes at least two diametrically opposed protrusions.

11. The access port clamp cover of claim 8 further including a seal receiving groove extending about and proximate a periphery of each of said covers and a resilient seal disposed in said seal receiving groove.

12. The access port clamp cover of claim 11 wherein said resilient seal is operable to elastically deform to provide a clamp load.

13. The access port clamp cover of claim 8 further including at least one of a through opening and groove in said handle and at least one of a retaining pin, fastener, and snap ring operable to engage at least one of said through opening and groove.

14. The access port clamp cover of claim 8 wherein at least one of said first cover and said second cover is operable to elastically deform to provide a clamp load.

15. The access port clamp cover of claim 8 further including a housing having an access port and at least one cover positioning feature disposed adjacent said access port.

16. An access port clamp cover assembly, comprising:

a first cover having a centrally disposed cylindrical member defining at least one protrusion extending radially outwardly and a handle extending from said cylindrical member;

a second cover defining a centrally disposed retaining member having an opening for receiving said handle and an annulus concentrically disposed about said opening, said annulus defining an inside diameter larger than an outside diameter of said cylindrical member and having at least one locking slot on said inside surface;

17. The access port clamp cover assembly of claim 16 wherein said cylindrical member includes at least two diametrically opposed protrusions and said annular member includes at least two opposed locking slots.

18. The access port clamp cover assembly of claim 16 further including a seal receiving groove extending about and proximate a periphery of each of said covers and a resilient seal disposed in said seal receiving groove, wherein said resilient seal is operable to elastically deform to provide a clamp load.

19. The access port clamp cover assembly of claim 16 wherein at least one of said first cover and said second cover is operable to elastically deform to provide a clamp load.

20. The access port clamp cover assembly of claim 16 further including a housing having an access port and at least one cover positioning feature disposed adjacent said access port.