Title:
Adaptor Frame
Kind Code:
A1


Abstract:
An adaptor frame comprising an isolated drain path formed in the adaptor frame at a first end of the adaptor frame is disclosed and claimed. An inboard wall is formed in the adaptor frame at the first end and the inboard wall is positioned adjacent an interstitial area. The interstitial area is between a bearing and the first end of the adaptor frame. The inboard wall provides a first limit for the isolated drain path. An outboard wall is formed in the adaptor frame at the first end and is separated from the inboard wall by a predetermined amount along the axial dimension of a shaft passing through the adaptor frame. The outboard wall provides a second limit for the isolated drain path.



Inventors:
Orlowski, David C. (Punta Gorda, FL, US)
Hoehle, Neil F. (Solon, IA, US)
Application Number:
11/893567
Publication Date:
02/21/2008
Filing Date:
08/16/2007
Primary Class:
International Classes:
F01D25/00
View Patent Images:
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Primary Examiner:
WIEHE, NATHANIEL EDWARD
Attorney, Agent or Firm:
HAMILTON IP LAW, PC (DAVENPORT, IA, US)
Claims:
What is claimed is:

1. An adaptor frame comprising: a. an isolated drain path formed in said adaptor frame at a first end of said adaptor frame; b. an inboard wall formed in said adaptor frame at said first end, wherein said inboard wall is positioned adjacent an interstitial area, wherein said interstitial area is between a bearing and said first end of said adaptor frame, and wherein said inboard wall provides a first limit for said isolated drain path; and, c. an outboard wall formed in said adaptor frame at said first end, wherein said outboard wall is separated from said inboard wall by a predetermined amount along the axial dimension of a shaft passing through said adaptor frame, and wherein said outboard wall provides a second limit for said isolated drain path.

2. The adaptor frame according to claim 1 wherein said adaptor frame first end is fashioned with at least one O-ring groove to engage a bearing housing.

3. The adaptor frame according to claim 1 further defined as not including said outboard wall.

4. The adaptor frame according to claim 1 wherein at least a portion of said inboard wall is formed by a bearing isolator.

5. The adaptor frame according to claim 1 further comprising an annular adaptor frame groove adjacent said inboard wall and said outboard wall, wherein said adaptor frame groove is in fluid communication with said isolated drain path.

6. The adaptor frame according to claim 5 wherein the radial dimension of said adaptor frame groove with respect to said shaft increases on a portion of said adaptor frame groove adjacent said isolated return path

7. The adaptor frame according to claim 1 wherein a radial distance between the ends of said inboard wall and said outboard wall and said shaft is in the range of 0.0001-1.0 inches.

8. The adaptor frame according to claim 1 wherein at least a portion of said inboard wall is formed by a bearing isolator and wherein at least a portion of said outboard wall is formed by said bearing isolator.

9. The adaptor frame according to claim 8 wherein said bearing isolator includes a labyrinth groove, wherein said bearing isolator includes a labyrinth return drain, and wherein said labyrinth return drain is in fluid communication with said isolated drain path.

10. An adaptor frame comprising: a. a first end fashioned to accept a bearing isolator, wherein said first end is engagable with a bearing housing at a bearing housing/adaptor frame interface, and wherein said bearing isolator is at least capable of retaining lubricant; b. a second end engagable with a pump casing; c. an isolated drain path formed in said adaptor frame at said first end, wherein said isolated drain path provides a conduit to return lubricant drained from said bearing isolator to said bearing housing; d. an inboard wall formed in said adaptor frame, wherein an inboard wall exterior face is oriented adjacent an interstitial area between a bearing and said adaptor frame, wherein an inboard wall interior face provides a first limit for said isolated drain path, and wherein said bearing is installed in said bearing housing; and, e. an outboard wall formed in said adaptor frame, wherein an outboard wall interior face provides a second limit for said isolated drain path, wherein said outboard wall interior face is adjacent said inboard wall interior face and separated therefrom by a predetermined amount along the axial dimension of a shaft passing through said bearing housing, said adaptor frame, and into said pump casing.

11. The adaptor frame according to claim 10 wherein said adaptor frame first end is fashioned with O-ring grooves to engage said bearing housing at said bearing housing/adaptor frame interface.

12. The adaptor frame according to claim 10 wherein at least a portion of said inboard wall is formed by a bearing isolator.

13. The adaptor frame according to claim 10 further defined as not including said outboard wall.

14. The adaptor frame according to claim 10 further comprising an annular adaptor frame groove adjacent said inboard wall and said outboard wall, wherein the axial dimension of said adaptor frame groove is defined by said inboard wall interior face and said outboard wall interior face, and wherein said adaptor frame groove is in fluid communication with said isolated drain path.

15. The adaptor frame according to claim 10 wherein at least a portion of said inboard wall is formed by a bearing isolator and wherein at least a portion of said outboard wall is formed by said bearing isolator.

16. The adaptor frame according to claim 15 wherein said bearing isolator includes a labyrinth groove, wherein said bearing isolator includes a labyrinth return drain, and wherein said labyrinth return drain is in fluid communication with said isolated drain path.

17. A pump assembly comprising: a. a pump casing, wherein said pump casing houses an internal portion of a pump, and wherein a shaft passing through at least a portion of said pump casing provides energy to said internal portion of a pump; b. a bearing housing, wherein said bearing housing is fashioned to accept at least one bearing, wherein said shaft passes through said bearing housing and rotationally engages said at least one bearing; c. an adaptor frame, wherein said adaptor frame is fashioned to provide an interface between said pump casing and said bearing housing, said adaptor frame comprising: i. an isolated drain path formed in said adaptor frame at a first end of said adaptor frame, wherein said first end of said adaptor frame is arranged adjacent said bearing housing; ii. an inboard wall formed in said adaptor frame, wherein said inboard wall is positioned adjacent an interstitial area between said at least one bearing and said adaptor frame, and wherein said inboard wall provides a first limit for said isolated drain path; and, iii. an outboard wall formed in said adaptor frame, wherein said outboard wall is separated from said inboard wall by a predetermined amount along the axial dimension of said shaft, wherein said shaft passes through said adaptor frame, and wherein said outboard wall provides a second limit for said isolated drain path.

18. A bearing isolator comprising: a. a stator; and, b. a rotor, wherein said stator and said rotor cooperate to form said bearing isolator, wherein said bearing isolator includes an inboard wall and an outboard wall, wherein said inboard wall and said outboard wall cooperate to form a labyrinth groove, wherein said labyrinth groove includes a labyrinth return drain that interfaces with an isolated drain path formed in an adaptor frame.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

Applicant claim priority under 35 U.S.C. § 119(e) of provisional U.S. Patent Application Ser. No. 60/838,219 filed on Aug. 17, 2006, which is incorporated by reference herein.

FIELD OF INVENTION

The present invention relates to an adaptor frame and bearing isolator for pumps wherein both the adaptor frame and the bearing isolator have multiple embodiments.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

No federal funds were used to develop or create the invention disclosed and described in the patent application.

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX

Not Applicable

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional side view of a pump assembly as found in the prior art.

FIG. 1A is a detailed cross-sectional view of a portion of the pump assembly from FIG. 1.

FIG. 2 is a cross-sectional exploded view of a pump assembly shown in FIG. 1.

FIG. 3 is a cross-sectional side view of a pump assembly employing a first embodiment of the present art.

FIG. 3A is a detailed cross-sectional view of a portion of the pump assembly from FIG. 3 employing the first embodiment of the present art.

FIG. 4 is a cross-sectional side view of a pump assembly employing a second embodiment of the present art.

FIG. 4A is a detailed cross-sectional view of a portion of the pump assembly from FIG. 4 employing the second embodiment of the present art.

FIG. 5 is a cross-sectional side view of a pump assembly employing a third embodiment of the present art.

FIG. 5A is a detailed cross-sectional view of a portion of the pump assembly from FIG. 5 employing the third embodiment of the present art.

FIG. 6 is a perspective partial cutaway view of the third embodiment of the present art.

FIG. 7 is a detailed cross-sectional view of the bearing isolator designed for use with the third embodiment of the present art adaptor frame.

FIG. 8 is and end view of the third embodiment of the present art adaptor frame.

FIG. 8A is a cross-sectional side view of the third embodiment of the present art adaptor frame as in FIG. 8 wherein connecting lines between FIG. 8 and FIG. 8A correspond to common surfaces.

FIG. 9 is a cross-sectional side view of a present art bearing isolator engaged with a prior art adaptor frame.

FIG. 10 is a cross-sectional side view of a prior art bearing isolator engaged with a present art adaptor frame.

DETAILED DESCRIPTION - LISTING OF ELEMENTS
ELEMENT DESCRIPTIONELEMENT #
Bearing Housing1
Adaptor Frame2
Pump Casing3
Pump Assembly4
Bearing5
Intentionally Blank6
Shaft7
Labyrinth Groove8
Labyrinth Return Drain9
Isolated Drain Path10
Interstitial Area11
Lubricant12
Isolated Lubricant Return Passage13
Lubricant Sump14
Lubricant Level15
Rotor16
O-Ring17
Bearing Housing/Adaptor Frame Interface18
Outboard Wall19
Present Art Adaptor Frame20
Stator21
Inboard Wall22
Inboard Wall Interior Face23
Inboard Wall Exterior Face24
Outboard Wall Interior Face25
Outboard Wall Exterior Face26
Bearing Isolator27
O-ring Groove28
Contaminant Drain29
Unitizing Ring30
Adaptor Frame Groove31
Intentionally Blank32
Bearing Isolator Inboard Wall33
Bearing Isolator Outboard Wall34
Contaminant Groove35
Shaft Aperture36

DETAILED DESCRIPTION

Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. Furthermore, the bearing isolator 27 used with the present art adaptor frame 20 includes, but is not limited to, those disclosed in U.S. Pat. Nos. 6,234,489, 6,062,568, 5,378,000, 5,221,095, and 4,175,752, all of which are incorporated herein by reference. By way of example, FIG. 10 shows a prior art bearing isolator 27 installed within the present art adaptor frame 20. The present art bearing isolators 27, such as those used in the first and third embodiments (FIGS. 3-3A and 5-8A, respectively), may also be used with prior art adaptor frames 2, as is shown in FIG. 9. Accordingly, the scope of the present art bearing isolators 27 is not limited by whether they are engaged with a prior art adaptor frame 2 or a present art adaptor frame 20.

The term “bearing isolator” as defined herein is meant to include such structures disclosed herein and in the prior art consisting of a stator 21 and a rotor 16 cooperating to protect a bearing 5 either through contaminant exclusion, lubricant retention, or both. However, the present art adaptor frame 20 may also be used without a bearing isolator 27, as shown in the second embodiment pictured in FIGS. 4 and 4A. In the second embodiment (explained in detail below), a simple labyrinth seal is used instead of a bearing isolator 27. Therefore, the scope of the present invention is not limited by whether a bearing isolator 27, simple labyrinth seal, or complex labyrinth seal, are used separately or in any combination thereof.

Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, a prior art pump assembly 4 and relevant portions thereof is shown in FIG. 1. FIG. 1 provides a cross-sectional side view of a typical prior art pump assembly 4, and FIG. 1A provides a detailed view of a portion of the bearing housing/adaptor frame interface 18. FIG. 2 shows the pump assembly 4 from FIG. 1 exploded into the three primary components of the pump assembly 4: the bearing housing 1, adaptor frame 2, and pump casing 3. A shaft 7 passes through each portion of the pump assembly 4 and is typically affixed to a pump impeller (not shown) at one end, and to a source of rotational power (not shown) at the opposite end, as is well known to those skilled in the art.

The bearing housing 1 is typically arranged with at least one bearing 5 positioned between the bearing housing 1 and the shaft 7, as indicated in FIGS. 1 and 2. As is well known to those skilled in the art, a portion of the bearing 5 is rotatable with the shaft 7 and a portion is affixed to the bearing housing 1. In many applications a bearing isolator 27 is positioned within the adaptor frame 2 to retain lubricant 12 within the bearing housing 1 and/or to protect the bearing(s) 5 in the bearing housing 1 from external contaminants that may enter the bearing housing 1 from the pump casing 3 or elsewhere. Often the bearing housing 1 includes a lubricant sump 14 filled to a specific lubricant level 15 with a specific lubricant 12. The lubricant 12 serves to lubricate the bearing(s) 5. When the shaft 7 rotates, a portion of the bearing(s) 5 rotate as well, which often causes lubricant 12 to splash around the bearing(s) 5 and potentially migrate away from the bearing housing 1 towards the adaptor frame 2 when the lubricant level 15 is at the appropriate value. This is because an appropriate lubricant level 15 is often high enough to submerge at least a portion of the bearing(s) 5 (see FIGS. 1 and 1A).

FIG. 1A provides a detailed cross-sectional view of a prior art bearing isolator 27 positioned within the bearing housing 1. In this embodiment of the prior art, the bearing isolator 27 functions to retain lubricant 12 within and exclude contaminants from the bearing housing 1. Many different types of bearing isolators 27 exist, as is well known to those skilled in the art. Bearing isolators 27 designed to retain lubricant 12 and exclude contaminants generally include a stator 21 and a rotor 16, and bearing isolators 27 designed to retain lubricant generally include only a stator 21. The rotor 16 is engaged with the shaft 7 and rotatable therewith, and the stator 21 is engaged with the adaptor frame 2. The rotor 16 and stator 21 may be fashioned to form a bearing isolator 27 having a plurality of corresponding radial and axial projections and grooves, and may employ a single unitizing ring 30 or a plurality of unitizing rings (not shown). The operation of bearing isolators 27 in such applications is well known to those skilled in the art, and therefore is not explained further herein.

Certain prior art bearing isolators 27 collect lubricant 12 splashed by the bearing 5 or other rotating components and drain or return the lubricant 12 to the lubricant sump 14, thus preventing escape of the lubricant 12 from the bearing housing 1 and providing lubricant 12 retention. As taught by the prior art, a separate bearing isolator 27 was required to be fit and inserted into the adaptor frame 2 in order for lubricant 12 to be returned to the bearing housing 1. The prior art also required that lubricant 12 collected in the bearing isolator 27 be drained or returned into the bearing housing 1 directly against the force and splash of lubricant 12 created by the bearing 5 or other rotating components of the equipment.

In prior art adaptor frames 2, lubricant 12 collected in the labyrinth groove 8 and drained from the labyrinth return drain 9 must first pass through the interstitial area 11, and then through the isolated lubricant return passage 13 to reach the lubricant sump 14. Lubricant 12 exiting the bearing isolator 6 through the labyrinth return drain 9 does so merely by the force of gravity since the labyrinth return drain 9 is located in the non-rotating portion (i.e., the stator 21) of the bearing isolator 27. When lubricant 12 drained from the labyrinth return drain 9 encounters lubricant 12 splashed or flung from the bearing 5 or other rotational components, the bearing isolator 27 cannot drain lubricant 12 back to the lubricant sump 14 effectively. This is because placing the bearing isolator 27 adjacent to the bearing 5 or other rotational components with merely an interstitial area 11 in between, the lubricant 12 splashed or flung from the rotational components impedes the flow of lubricant 12 drained from the bearing isolator 27 when the drained lubricant 12 is in the interstitial area 11. That is, there is no structure in the prior art that alleviates the effects the splash or force of lubricant 12 (created by rotational components in the interstitial area 11) has on lubricant 12 drained from the bearing isolator 27 when that lubricant 12 is in the interstitial area 11. The centrifugal force and splash the bearing 5 or other rotational components impart to lubricant 12 in the interstitial area 11 is often greater than the gravitational force imparted to that lubricant 12. That is, the lubricant 12 draining from the bearing isolator 27 must work against the force and splash of lubricant 12 adjacent the bearing 5 or other rotational components near the interstitial area 11 to drain properly from both the bearing isolator 27 and the interstitial area 11.

The failure of the prior art described above is accentuated in certain situations, depending on the lubricant level 15 in the lubricant sump 14. FIGS. 1 and 1A illustrate an embodiment of the prior art wherein the bearing 5 is rotating in the lubricant level 15, as is typically the situation for this type of configuration. The rotation of the bearing 5 in the lubricant 12 creates a splash of lubricant 12 in the interstitial area 11 and adversely affects draining of lubricant 12, as described above. If lubricant 12 in the interstitial area 11 overcomes the forces imparted to that lubricant 12 by the bearing 5 or other rotating components, the bearing isolator 27 will then operate properly so that lubricant 12 may be returned to the lubricant sump 14 by the isolated lubricant return passage 13 shown in FIG. 1A. Other embodiments of the prior art, which are not shown herein, do not provide an isolated lubricant return passage 13 and rely simply on the lubricant 12 in the interstitial area 11 to return to the lubricant sump 14 by draining through the bearing 5.

The various embodiments of the present art, shown in FIGS. 3-8 and 10, illustrate an adaptor frame 20 that combines the functions of attaching the bearing housing assembly 1 to the pump casing 3 while providing an improved configuration for returning lubricant 12 to the lubricant sump 14. The present art adaptor frame 20 may be used with the present art bearing isolator 27, as shown in FIGS. 5 and 5A, or it may be used with prior art bearing isolators 27, as shown in FIG. 10. Furthermore, the present art bearing isolator 27 may be used with prior art adaptor frames 2, as shown in FIG. 9. All embodiments of the present art adaptor frame 20 are fashioned with a shaft aperture 36 through which the shaft 7 passes (see FIG. 8), as in prior art adaptor frames 2.

As shown in FIGS. 3-5, the present art adaptor frame 20 utilizes an isolated drain path 10 for lubricant 12 return to improve the lubricant 12 retention function. This improvement results from the shielding effect the inboard wall 22 provides to lubricant 12 drained from the labyrinth drain 9. The improved lubricant 12 retention significantly decreases the likelihood of lubricant 12 leakage from the bearing housing 1, which may ultimately result in catastrophic bearing 5 failure. The present art adaptor frame 20 shown herein abuts the bearing housing 1 at the bearing housing/adaptor frame interface 18. O-ring grooves 28 may be fashioned in the present art adaptor frame 20 and O-rings 17 may be placed within the O-ring grooves 28 to seal the bearing housing/adaptor frame interface 18. Other convenient sealing means known to those skilled in the art may be used without departing from the spirit and scope of the present invention. Sealing the bearing housing/adaptor frame interface 18 prevents lubricant 12 from leaking from the bearing housing 1 along the bearing housing/adaptor frame interface 18.

As noted, the present art adaptor frame 20 provides an isolated drain path 10 to the isolated lubricant return passage 13 for lubricant 12 drained from the bearing isolator 27. The isolated drain path 10 is generally formed by an inboard wall 22 and an outboard wall 19 fashioned in the present art adaptor frame 20. As shown in the first embodiment (FIGS. 3 and 3A), a portion of the outboard wall 19 may be formed by the bearing isolator 27 (either a portion of the stator 21 or a portion of the rotor 16). A portion of the stator 21 forms a portion of the outboard wall 19 in the first embodiment and is positioned adjacent the adaptor frame groove 31. The annular adaptor frame groove 31 collects and drains lubricant 12 to the isolated drain path 10 (See FIG. 8). This configuration provides an isolated return path 10 for lubricant 12 drained from the bearing isolator 27 that spans the entire distance from the bearing isolator 27 to the lubricant sump 14. The isolated drain path 10 protects the lubricant 12 drained from the bearing isolator 27 from any lubricant 12 splash and force imparted by the bearing 5 or other rotating components. Lubricant 12 splash and other force is still present in the interstitial area 11, but the inboard wall 22 prevents the splash and other forces from affecting lubricant 12 drained from the bearing isolator 27. Removing the influence of splashing lubricant 12 upon lubricant 12 in close proximity to the bearing isolator 27 decreases the likelihood of lubricant 12 leakage though the bearing isolator 27 due to more effective lubricant 12 drainage from the bearing isolator 27. This also improves pump reliability due to increased efficiency of lubricant 12 retention. Lubricant 12 splashed or flung from the bearing(s) 5 contacts the inboard wall exterior face 24 as the inboard wall shields the lubricant 12 drained from the bearing isolator 27. The cross-sectional shape of the isolated drain path 10 and the adaptor frame groove 31 may be of any convenient shape depending on the application, and the distance from the shaft 7 at which the isolated drain path 10 connects to the isolated lubricant return passage 13 will vary depending on the specific embodiment. In the third embodiment (shown in FIGS. 5, 5A, 6, 7, and 8, and explained in greater detail below) the isolated drain path 10 is rounded in a semi-circular shape (as shown in FIG. 7) rather than cylindrical. The semi-circular shape helps to funnel the lubricant 12 drained from the bearing isolator 12 into the isolated lubricant return passage 13. Other shapes may be used for the adaptor frame groove 31 or isolated drain path 10 in other embodiments not shown herein. The axial dimension (along the axis of the shaft 7) of the isolated drain path 10 is defined by the inboard wall 22 and the outboard wall 19. The inboard wall interior face provides a first limit for the axial dimension of the isolated drain path 10, and the outboard wall interior face 25 provides a second limit for the axial dimension of the isolated drain path 10. The inboard wall exterior face 24 comprises a portion of the bearing housing/adaptor frame interface 18 and is adjacent the interstitial area 11. The outboard wall exterior face 26 is adjacent the interior portion of the present art adaptor frame 20.

In the embodiment shown in FIGS. 3 and 3A, the bearing isolator 27 is designed for both lubricant 12 retention and contaminant exclusion. FIG. 3A provides a detailed view of the present art bearing isolator 27 and present art adaptor frame 20 wherein the labyrinth groove 8 essentially forms a portion of the isolated drain path 10 in the form of an adaptor frame groove 31, which is built into the present art adaptor frame 20 (as best seen from FIGS. 3A and 8). Contaminants are collected in the contaminant groove 35 and expelled from the bearing isolator 27 through the contaminant drain 29. In this embodiment, no separate labyrinth return drain 9 or labyrinth groove 8 is required (as it is for the bearing isolator shown in FIG. 1A), and lubricant 12 drains from the bearing isolator 27 directly into the adaptor frame groove 31 or the isolated drain path 10. The isolated drain path 10 is connected to or interfaces with the isolated lubricant return passage 13 to provide for a completely isolated conduit from the bearing isolator 27 to the lubricant sump 14. The bearing housing/adaptor frame interface 18, which is located between the adaptor frame 2 and the bearing frame 1, may be sealed with an O-ring 17 or similar device to prevent any communication between the interstitial area 11 and the isolated lubricant return passage 13.

As noted above, in the first embodiment of the present art adaptor frame 20 shown in FIGS. 3 and 3A, a portion of the outboard wall 19 is formed by the stator 21. In other embodiments of the present art adaptor frame 20 not shown herein, the outboard wall 19 may be composed of multiple portions of either the stator 21 or rotor 16 alone, or the stator 21 and rotor 16 in combination.

In the second embodiment of the present art adaptor frame 20 shown in FIGS. 4 and 4A, the present art adaptor frame 20 is not used in conjunction with a bearing isolator 27 and instead employs a simple labyrinth seal, as is known to those skilled in the art. Therefore, the entire outboard wall 19 and inboard wall 22 are fashioned in the present art adaptor frame 20 and no portion of either the inboard wall 22 or outboard wall 19 is formed by a bearing isolator 27. In this embodiment, the present art adaptor frame 20 serves to retain lubricant 12 in the same manner as a bearing isolator 27 used for lubricant 12 retention, but there is no contaminant exclusion functionality other than the close clearance that may be fashioned between the shaft 7 and the outboard wall 19 and inboard wall 22. That is, in the second embodiment the present art adaptor frame 20 functions similarly to a bearing isolator 27 having only a stator 21. However, to provide lubricant 12 retention, no separate bearing isolator 27 is required. As in the first embodiment, the inboard wall 22 in the second embodiment shields lubricant 12 in the isolated drain path 10 from lubricant 12 splash or centrifugal force of the bearing(s) 5. Consequently, lubricant 12 retention and resistance to leakage are improved compared to prior art adaptor frames 2. The bearing housing/adaptor frame interface 18 in the second embodiment may be sealed in any manner as the first embodiment may be sealed.

A third embodiment of the present art adaptor frame 20 and bearing isolator 27 is shown in FIGS. 5-7. The bearing isolator 27 in the third embodiment comprises a portion of both the inboard wall 22 and outboard wall 19, indicated as the bearing isolator inboard wall 33 and bearing isolator outboard wall 34, respectively (best shown in FIGS. 5A and 6). The bearing isolator inboard wall 33 and bearing isolator outboard wall 34 form a labyrinth groove 8 in the stator 21, which functions similarly to the adaptor frame groove 31 in the first embodiment. Lubricant 12 may be collected in the labyrinth groove 8 and drained from the bearing isolator 27 through the labyrinth return drain 9 into the isolated drain path 10, and subsequently returned to the lubricant sump 14. As in the first and second embodiments, lubricant 12 drained from the bearing isolator 27 is shielded from the lubricant 12 splash or centrifugal force caused by the bearing(s) 5. The third embodiment of the present art adaptor frame 20 does not utilize an adaptor frame groove 31 as do the first and second embodiments; rather, the third embodiment utilizes a labyrinth groove 8 in the stator 21 of the bearing isolator 27. The present art bearing isolator 27 in the third embodiment also utilizes a contaminant groove 35 to exclude contaminants and expel them from the bearing isolator 27 through the contaminant drain 29. The bearing housing/adaptor frame interface 18 in the third embodiment may be sealed in any manner as the first embodiment may be sealed.

In all embodiments of the present art adaptor frame 20, the labyrinth groove 8 may be a single groove or may be formed through a plurality of grooves. Furthermore, a portion of the bearing isolator 27 may be used to form a portion of the adaptor frame groove 31, as in the first embodiment shown in FIGS. 3 and 3A, or the bearing isolator 27 may be fashioned with a labyrinth groove 8 as in the third embodiment shown in FIGS. 5, 5A, 6, and 7. As described herein, FIGS. 3, 3A, 5, 5A, 6, and 7 illustrate embodiments of the present art bearing isolator 27 having contaminant exclusion and lubricant 12 retention capability. The type of bearing isolator 27 employed with the present art adaptor frame 20 in no way limits the scope of the invention relating to the present art adaptor frame 20.

It should be noted that the present invention is not limited to the specific embodiments pictured and described herein, but is intended to apply to all similar adaptor frames facilitating improved return of lubricant 12 to the lubricant sump 14. Modifications and alterations from the described embodiments will occur to those skilled in the art without departure from the spirit and scope of the present invention.