TECHNICAL FIELD

The present disclosure relates to seals for rotating shafts. Particularly, but not exclusively, the present disclosure relates to a seal assembly for a bearing. Further, embodiments of the present disclosure disclose a labyrinth seal assembly for sealing a fluid bearing.

BACKGROUND OF THE DISCLOSURE:

Sealing assemblies are generally provided between two or more components that provide ingress protection from foreign particles that may intrude between such components and affect functioning of the components thereof. Generally, the sealing assemblies are employed at an open portion of the components or at intermediate portions with suitable positioning means. Further, for components that are employed in dynamic mechanisms, the sealing assemblies may accompany a bearing, which may be configured to assist in transmission of power and/or motion between the components involved in such dynamic mechanism. However, the sealing assemblies employed in such dynamic mechanisms are static and are positioned on respective housing or shaft, but rotate with respect to each other, due to which the sealing assemblies may be subjected to wear and tear, on prolonged usage.

With advent of technology, efforts have been made to improve the sealing assemblies for dynamic mechanisms and with such efforts, labyrinth sealing assemblies have been developed. The labyrinth sealing assembly includes a plurality of sealing leaves or disks, which may be positioned between two components having relative motion such as, a shaft, journal and a housing. Further, each sealing disk of the plurality of sealing disks of the labyrinth sealing assembly may interpose with one another, in order to induce a tortuous path for preventing leakage.

The seal disks in the conventional labyrinth sealing assemblies are straight and include a clearance region that may be defined along a longitudinal or horizontal direction of such seal disks to avoid rubbing of the said seal disks with the housing, whereby leading to premature wear of the labyrinth sealing assemblies. However, the clearance region along the longitudinal direction of the seal disks may provide sufficient space for foreign particles including, but not limited to, dust, water, oil and the like, to travel between the seal disks to reach other successive components. Further, such configuration of the seal disks may allow leakage of fluid such as lubricants, contained in the labyrinth seal assemblies, as the fluid easily may flow pass the seal disks and through the clearance region along the longitudinal direction of the seal disks. Also, the conventional labyrinth seal assemblies include a number of parts that may have to be individually assembled about the component such as a shaft, journal or a housing, for sealing from the foreign particles. For example, the bearing unit may be positioned first on a shaft and then, each seal disk may independently and successively be positioned on either sides of the bearing unit. Flowever, the seal disk may be required to be externally fastened or secured on the shaft, which would require a skilled operator. This way, assembly-time of the labyrinth sealing assembly increase and, servicing-time of the sealing assembly may also consequently increase due to necessity of re-assembling the parts upon servicing.

The present disclosure is directed to overcome one or more limitations stated above or any other limitation associated with the conventional arts.

SUMMARY

One or more shortcomings of the limitations stated above are overcome by a labyrinth seal assembly for a bearing as claimed, and additional advantages are provided through the provision of the assembly as claimed in the present disclosure. Additional features and advantages are realized through the aspects and techniques of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure.

In an exemplary embodiment of the present disclosure, a labyrinth seal assembly for a bearing is disclosed. The labyrinth seal assembly consists of a housing that is connectable to the bearing. The housing consists of a first enclosure portion and a second enclosure portion, where the first enclosure portion and the second enclosure portion are engaged and relatively displaceable, during operation of the bearing. Further, the assembly includes a plurality of seal disks disposed between the first enclosure portion and the second enclosure portion, where each seal disk of the plurality of seal disks consists of a kink portion that is defined along a length of each of the plurality of seal disks. A first set of seal disks of the plurality seal disks is connectable to the first enclosure portion and interposes with a second set of seal disks of the plurality of seal disks which is connectable to the second enclosure portion about the kink portion. Further, at least one first end disk is connectable to the first enclosure portion (1), where the at least one first end disk is made of flexible material and is positioned at one end of the labyrinth seal assembly. The at least one first end disk forms a sealed chamber with the first enclosure portion of the housing.

In an embodiment, the labyrinth seal assembly consists of at least one second end disk which is positioned at an other end opposite to one end of the labyrinth seal assembly, where the second end disk is connectable to the second enclosure portion.

In an embodiment, the at least one second end disk is made of flexible material and forms a sealed chamber with the second enclosure portion of the housing.

In an embodiment, the first set of seal disks of the plurality of seal disks are longitudinally interposed about the kink portion between the second set of seal disks of the plurality of seal disks to define a clearance region and an oblique passage between successive seal disks of the plurality of seal disks;

In an embodiment, each of the at least one first end disk and the at least one second end disk are defined with an extended lip region, to sealingly engage with the housing.

In an embodiment, each seal disk of the plurality of seal disks is defined with a free end disposed between the first enclosure portion and the second enclosure portion to define the clearance region and the oblique passage.

In an embodiment, the kink portion is defined between a fixing end and the free end of the plurality of seal disks and increases flow path between successive seal disks of the plurality of seal disks.

In an embodiment, the plurality of seal disks are made from a rigid material.

In an embodiment, the first enclosure portion is defined with a one or more of grooves to accommodate O-rings.

In an embodiment, the labyrinth seal assembly consists of a projection that extends from the first enclosure portion towards the second enclosure portion, and at least one first end disk is disposed between the projection and the second enclosure portion. In an embodiment, the projection and the at least one first end disk are defined with the kink portion to form the sealed chamber with the first enclosure portion.

In an embodiment, the labyrinth seal assembly consists of a flange that extends from the second enclosure portion towards the first enclosure portion, and at least one first end disk is disposed between the flange and the projection, where the flange is configured to restrain movement of at least one of the first enclosure portion and the plurality of seal disks.

In an embodiment, the first enclosure portion and the second enclosure portion are defined with a plurality of detents that are structured to selectively restrict transverse movement of the plurality of seal disks.

In an embodiment, the flange engages with the at least one first end disk in the first set of seal disks from the plurality of seal disks.

It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined together to form a further embodiment of the disclosure.

The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

The novel features and characteristics of the disclosure are set forth in the description. The disclosure itself, however, as well as a preferred mode of use, further advantages thereof, will best be understood by reference to the following description of an illustrative embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example only, with reference to the accompanying drawings wherein like reference numerals represent like elements and in which:

Fig. 1 illustrates a sectional view of a labyrinth seal assembly, in accordance with an embodiment of the present disclosure. The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF THE DISCLOSURE:

The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that, the conception and specific embodiments disclosed may be readily utilized as a basis for modifying other mechanisms, devices, and assemblies for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that, such equivalent constructions do not depart from the scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristics of the disclosure, both as to its mechanism and assembly, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.

The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusions, such that a mechanism, an assembly, or a device that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or device or method. In other words, one or more elements in a system or apparatus proceeded by “comprises... a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.

In accordance with various embodiments of the present disclosure, a labyrinth seal assembly for a bearing is disclosed. The labyrinth seal assembly consists of a housing that is connectable to the bearing. The housing consists of a first enclosure portion and a second enclosure portion, where the first enclosure portion and the second enclosure portion are engaged and relatively displaceable, during operation of the bearing. Further, the assembly includes a plurality of seal disks disposed between the first enclosure portion and the second enclosure portion, where each seal disk of the plurality of seal disks consists of a kink portion that is defined along a length of each of the plurality of seal disks. A first set of seal disks of the plurality seal disks is connectable to the first enclosure portion and interposes with a second set of seal disks of the plurality of seal disks which is connectable to the second enclosure portion about the kink portion. Further, at least one first end disk is connectable to the first enclosure portion, where the at least one first end disk is made of flexible material and is positioned at one end of the labyrinth seal assembly. The at least one first end disk forms a sealed chamber with the first enclosure portion of the housing.

Reference will now be made to the exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. Wherever possible, same numerals will be used to refer to the same or like parts. The following paragraphs describe the present disclosure with reference to Fig. 1.

Figure 1 is an exemplary embodiment which illustrates a sectional side view of a labyrinth seal assembly (100). The labyrinth seal assembly (100) maybe positioned adjacent to a bearing [not shown in Figures] and may protect the bearing by sealing intrusion of foreign particles on either sides. The labyrinth seal assembly (100) may be mounted at an end portion of the bearing or be mounted on a rotational shaft or journal accommodating such bearing, for providing necessary sealing action during static and/or dynamic operations. The labyrinth seal assembly (100) may include a housing that is connectable to the bearing. The housing may include a first enclosure portion (1) and a second enclosure portion (2). The first enclosure portion (1) and the second enclosure portion (2) may be concentric to one another and that the second enclosure portion (2) may be disposable within the first enclosure portion (1). The first enclosure portion (1) and the second enclosure portion (2) may be fitted by means including, but not limited to, press-fitting, snap fitting, adhesive bonding, and any other non-permanent joining technique having low turn-around time for assembly. Further, at least one of the first enclosure portion (1) and the second enclosure portion (2) may be adapted to relatively displace with respect to each other, during operation of the labyrinth seal assembly (100) and/or the bearing and the shaft on which the labyrinth seal assembly (100) may be mounted. That is, for example, the second enclosure portion (2) may be configured to be positioned on a journal for ingress protection, while at the same time, may adaptably rotate along with such journal. The first enclosure portion (1) may be connected to a static section such as, but not limited to, a housing of a component, a platform accommodating the labyrinth seal assembly (100), a base portion of the bearing, and any other static surface about which the second enclosure (2) may relatively displace. Alternatively, relative displacement between the first enclosure portion (1) and the second enclosure portion (2) may also be achieved by configuring the labyrinth seal assembly (100) in such a way that, the second enclosure portion (2) is connected to the static surface of the component, while the first enclosure portion (1) is connected to at least one of the bearing, the journal or any other moveable component with which the journal and/or the bearing may be associated.

In an embodiment, the housing may be adapted to contain an anti-friction fluid between the first enclosure portion (1) and the second enclosure portion (2) for suitably lubricating the labyrinth seal assembly (100) and further restrict any foreign particles from traversing through the labyrinth seal assembly (100). Such anti-friction fluid may be selectively injected into the housing on assembly of the first enclosure portion (1) relative to the second enclosure portion (2).

Further, the labyrinth seal assembly (100) may include a plurality of seal disks (3, 4), adaptably disposable between the first enclosure portion (1) and the second enclosure portion (2). The plurality of seal disks (3, 4) may be connectable with the first enclosure portion (1) and the second enclosure portion (2), to provide ingress protection. In an embodiment, a first set of seal disks (3) of the plurality of seal disks (3, 4) may be connectable to the first enclosure portion (1), while a second set of seal disks (4) of the plurality of seal disks (3, 4) may be connectable to the second enclosure portion (2). Each seal disks of the first set of seal disks (3) may be longitudinally interposed between the second set of seal disks (4) to define a clearance region therebetween. The clearance region may sufficiently dimensioned for the first set of seal disks (3) to relatively traverse pass the second set of seal disks (4), during operation of the labyrinth seal assembly (100) and in-tum that of the bearing and the journal. Additionally, each seal disk of the plurality of seal disks (3, 4) may be defined with a kink portion (11) along a length of each of the plurality of seal disks (3, 4). The kink portion (11) may be either formed during manufacturing or may be induced by plastically deformation on manufacturing of the plurality of seal disks (3, 4). In an embodiment, the kink portion (11) may be profiled to include either a sharp bend or a smooth curved bend along the length of each of the plurality of seal disks (3, 4). Further, the bend formed due to the kink portion (11) defines a void section about a linear trajectory along the length of the plurality of seal disks (3, 4). The first set of seal disks (3) and the second set of seal disks (4) of the plurality of seal disks (3, 4) may be aligned such that, each of the plurality of seal disks (3, 4) may interpose about the kink portion (11) of subsequent seal disk. That is, the first set of seal disks (3) of the plurality seal disks (3, 4) interposes with the second set of seal disks (4) of the plurality of seal disks (3, 4) about the kink portion (11) to define the clearance region. Furthermore, the kink portion (11) of one of the plurality of seal disks (3, 4) may be positioned in the void section of subsequent seal disk of the plurality of seal disks (3, 4). Such configuration of interposing the plurality of seal disks (3, 4) about the kink portion (11) may define an oblique passage between successive seal disks of the plurality of seal disks (3, 4) and increases travel length or flow path for intruded foreign particles. At the same time, the oblique passage may also increase the travel length of any foreign particles and the anti-friction fluid contained in the labyrinth seal assembly (100) and prevents any leakage of the fluid therefrom. In an embodiment, though the first set of seal disks (3) and the second set of seal disks (4) may be manufactured with other profiles [such as, wedge shaped, triangular, conical, and the like] that may define the void space and increase length of flow path, such profiles may not induce constricted flow path by way of oblique passage as defined by the kink portion (11). Such constricted oblique passage may be defined in conjunction with positioning of the first set of seal disks (3) and the second set of seal disks (4) relative to one another. Additionally, the oblique passage being defined by the kink portion (11) may be configured to restrict quantity and/or rate of flow of fluid including, but not limited to, anti- frictional fluid, between the first set of seal disks (3) and the second set of seal disks (4), whereby substantially reducing failure condition of the seal assembly (100). Also, the kink portion (11) may enable ease in assembling, due to flexibility being imparted to the first set of seal disks (3) and the second set of seal disks (4).

In an embodiment, each seal disk of the plurality of seal disks (3, 4) may include a fixing end and a free end. The fixing end of the plurality of seal disks (3, 4) may be configured to fix the seal disk to at least one of the first enclosure portion (1) and the second enclosure portion (2). The free end of the seal disk is defined away and opposite to the fixing end, and may be disposed between the first enclosure portion (1) and the second enclosure portion (2) to define the clearance region and the oblique passage. The kink portion (11) in each of the plurality of seal disks (3, 4) may be defined between the fixing end and the free end and may increase length of the clearance region and flow path between successive seal disks of the plurality of seal disks (3, 4). Further, the free end of each seal disk of the plurality of seal disks (3, 4) may be rigid in structure, while the free end may also be formed to be flexible. Also, the free end of plurality of seal disks (3, 4) may be lubricated or greased, in order to minimize frictional losses that may occur during operation of the labyrinth seal assembly (100).

In the exemplary embodiment, the plurality of seal disks (3, 4) may be made from at least one of a rigid material, a flexible material, and a partially rigid-partially flexible material, based on positioning of the seal disks within the housing. Further, at least one seal disk in the first set of seal disks (3) and the second set of seal disks (4) may be made from flexible material, whereas subsequent seal disks in the first set of seal disks (3) and the second set of seal disks (4) may be made from rigid materials. In an exemplary embodiment, at least one of the first set of seal disks (3) and the second set of seal disks (4) include at least one first end disk (5) connectable to the first enclosure portion (1), that may be positioned at one end of the labyrinth seal assembly (100) to define a sealed chamber with the first enclosure portion (1) of the housing. Further, the at least one first end disk (5) may be made of flexible material such that, the at least one first end disk (5) may selectively deform [either due to plasticity or due to elasticity] to sealing engage with a section of the first enclosure portion (1). Furthermore, the second set of seal disks (4) of the plurality of seal disks (3, 4) includes at least one second end disk (6), which may be positioned at an other end, which is opposite to one end of the labyrinth seal assembly (100), and may be connectable to the second enclosure portion (2). The at least one second end disk (6) may be made of flexible material and forms a sealed chamber with at least one seal disk of the first set of seal disks (3). The at least one second end disk (6) may be configured to engage with at least the free end, the kink portion (11) and the fixed end of one of the first set of seal disks (3). Such configuration of the at least one second end seal disk (6) may require fluid pressure to be applied by the fluid within the housing, to elastically deform and allow passage into and out from the housing. That is, flexible material of the at least one second end disk (6) may ensure ingress sealing during variation in fluid pressure within the seal assembly (100).

In an exemplary embodiment, the at least one first end disk (5) and the at least one second end disk (6) are defined with an extended lip region or a face, which has interference/contact to sealingly engage with surrounding faces of the housing to provide ingress protection from foreign particles and also prevents leakage of the anti-friction fluid contained within the housing. The at least one first end disk (5) and the at least one second end disk (6) form a closed/sealed chamber with thin clearance passage constructed by intermediate disk where the anti-friction fluid like but not limited to lubricant, grease, oil may be completely arrested. This anti-friction fluid increases the smooth functioning of the labyrinth seal assembly (100) and extend the life of the labyrinth seal assembly (100) and the bearing.

In an embodiment, the first enclosure portion (1) of the housing may include a projection (8) extending from the first enclosure portion (1) towards the second enclosure portion (2), where the projection (8) is positioned proximal to the one end of the labyrinth seal assembly (100). Further, the at least one first end disk (5) may be disposed between the projection (8) and the second enclosure portion (2) to form the sealed chamber. Furthermore, the projection (8) and the at least one first end disk (5) are defined with the kink portion (11) to suitably accommodate the plurality of seal disks (3, 4) and form the sealed chamber with the first enclosure portion (1).

In an embodiment, the first enclosure portion (1) and the second enclosure portion (2) of the housing may be made of a rigid material, to impart structural stability to the labyrinth seal assembly (100). Additionally, the second enclosure portion (2) of the housing may be defined with a flange (9), that may extend from the second enclosure portion (2) towards the first enclosure portion (1). The flange (9) may be configured to restrain movement of at least one of the first enclosure portion (1) and the plurality of seal disks (3, 4), that may be positioned on the second enclosure portion (2). Also, the flange (9) may engage with the at least one first end disk (5) positioned at one end of the labyrinth seal assembly (100). Further, the flange (9) may engage the at least one seal disk of the plurality of seal disks (3, 4) and the at least one first end disk (5) about the kink portion (11) such that, the at least one first end disk (5) and the flange (9) may impede entry of foreign particles from one end of the labyrinth seal assembly (100).

In an embodiment, the at least one first end disk (5) may be disposed between the flange (9) and the projection (8).

In an embodiment, the first enclosure portion (1) of the housing may be defined with one or more grooves to accommodate O-rings (7). The O-rings (7) may provide suitable sealing arrangement from transverse direction of the labyrinth seal assembly (100).

In an embodiment, the first enclosure portion (1) and the second enclosure portion (2) may be defined with a plurality of detents (10). The plurality of detents (10) may be configured to selectively restrict transverse movement of the plurality of seal disks (3, 4). In an embodiment, the plurality of seal disks (3, 4), the first end disk (5) and the second end disk (6) may be made of but not limited to polymers, nylon-based polymer, Polyurethane (Pu) based polymer and high-density polyethylene (HDPE) based polymer.

In an embodiment, the labyrinth seal assembly (100) may be pre-assembled at a predetermined location and may be transported or conveyed to be fitted on a desired component without having to dis-assemble. This way, assembling-lead-time of the component and the labyrinth seal assembly (100) may be reduced, as individual alignment and orientation is eliminated.

In an embodiment, the labyrinth seal assembly (100) provides ingress protection for the bearings, as the plurality of disks (3, 4), the at least one first end disk (5) and the at least one second end disk (6) restricts passage of dust particles and liquid through the labyrinth seal assembly (100). The ingress protection form dust particles and liquid results in increased seal life and increase bearing life. Further, corrosion of internal components of the bearing are prevented.

In an embodiment, the at least one first end disk (5) and the at least one second end disk (6) of the labyrinth seal assembly (100) enables accommodation of the anti-friction fluid within the housing and increases the life of the labyrinth seal assembly (100). Further, the anti- friction fluid trapped within the labyrinth seal assembly (100) acts as a leakage barrier and restricts entry and exit of foreign particles with respect to the bearing.

Equivalents:

The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.

The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within scope of the embodiments as described herein.

Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

Any discussion of documents, acts, materials, devices, articles and the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other modifications in the nature of the disclosure or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.