Description:TECHNICAL FIELD
[0001] The present invention generally relates to a washing machine bearing assembly. More particularly, the invention describes a washing machine bearing assembly with a housing having a seal hub surface, wing shaped collars and ribs, the washing machine bearing assembly being made of polymer.

BACKGROUND OF THE INVENTION
[0002] A front loading washing machine drum is driven by a motor and shaft through a bearing assembly. A typical bearing assembly consists of two ball bearings. The housing to house these ball bearings are made up of cast iron. There are many disadvantages associated with these assemblies such as, 1. heavier housing due to usage of cast iron material, 2. high energy use due to multiple process involved in the manufacturing, 3. misalignment of front and rear bearing mount surface geometry, resulting in imbalance, 4. cast iron housing rusting in case of water entry, resulting in bearing fitment loss and bearing failure, 5. cast iron housing requires pre heating of up to 70 degrees Centigrade during washing tub moulding over cast iron housing, 6. requirement of skilled labour and tooling for bearing mounting into the housing after washing tub moulding.
[0003] Various washing machine bearing assemblies that try to solve these disadvantages are known in the art. For example, United States patent US8590347 describes a bearing assembly for a washing machine having a polymeric housing and a polymeric spacer. United States patent application US2022178402 describes a power-plant nacelle bearing housing having stiffening ribs. United States patent US2592294 describes a railway journal bearing having wing shaped flanges to limit movement of the bearing. However, the above prior art described herein do not make use of the ribs or wing shaped flanges for better bonding with the structure. In addition, in a washing machine bearing assembly, the bonding of the spacer to the housing and in extension the bonding of the bearing assembly to the washing machine drum and washing machine tub seems to pose a challenge.
[0004] Therefore, there is a need for simplifying the washing machine design, assembly process, improve bonding to the structure and optimize the performance of the bearing assembly.

OBJECT AND SUMMARY OF THE INVENTION
[0005] An object of the present invention is to provide a washing machine bearing assembly having at least one front bearing and at least one rear bearing spaced apart along a central axis, a spacer at least partially associated with the at least one front bearing and the at least one rear bearing. The spacer includes a plurality of axial fins on the surface of the spacer. The washing machine bearing assembly further includes a polymeric housing to house the at least one front bearing, the at least one rear bearing and the spacer. The polymeric housing comprises a negatively drafted seal hub surface and a plurality of axial ribs.
[0006] Another object of the present invention is a washing machine bearing assembly that includes at least one front bearing and at least one rear bearing spaced apart along a central axis, a spacer at least partially associated with the at least one front bearing and the at least one rear bearing. The spacer comprises a plurality of axial fins on the surface of the spacer. The washing machine bearing assembly further includes a housing to house the at least one front bearing, the at least one rear bearing and the spacer. The housing is made up of a polymeric material, a plastic material, a ceramic material, a composite material, aluminium, metal alloys or a sintered material or a combination thereof. The spacer is made up of a polymeric material, a plastic material, a ceramic material, a composite material, aluminium, metal alloys, a sintered material or a combination thereof. The housing includes a negatively drafted seal hub surface and the plurality of axial ribs.
[0007] These and other objects of the invention herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing the spirit thereof, and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The embodiments of the invention are illustrated in the accompanying drawings, throughout which the reference letters indicate corresponding part in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0009] Figure 1 illustrates a washing machine bearing assembly according to an embodiment of the present invention.
[0010] Figure 2 illustrates a prior art washing machine bearing assembly.
[0011] Figure 3 illustrates a washing machine bearing with grooves according to an embodiment of the present invention.
[0012] Figure 4 illustrates a prior art spacer used in a washing machine bearing assembly.
[0013] Figure 5 illustrates a spacer in a washing machine bearing assembly according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[0014] While various embodiments of the invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions may occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed.
[0015] In the specification and the claims which follow, reference will be made to a number of terms which shall be defined to have the following meanings:
[0016] The singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not. “Substantially” means a range of values that is known in the art to refer to a range of values that are close to, but not necessarily equal to a certain value.
[0017] Other than in the examples or where otherwise indicated, all numbers or expressions referring to quantities of ingredients, reaction conditions, and the like, used in the specification and claims are to be understood as modified in all instances by the term “about.” In some aspects of the current disclosure, the terms “about” or “approximately” are defined as being close to as understood by one of ordinary skill in the art, and in one non-limiting embodiment the terms are defined to be within 10%, alternatively within 5%, alternatively within 1%, or alternatively within 0.5%.
[0018] As used herein, the term “substantially” and its variations are defined as being largely but not necessarily wholly what is specified as understood by one of ordinary skill in the art, and in one non-limiting aspect substantially refers to ranges within 10%, within 5%, within 1%, or within 0.5%.
[0019] Various numerical ranges are disclosed herein. Because these ranges are continuous, they include every value between the minimum and maximum values. The endpoints of all ranges reciting the same characteristic or component are independently combinable and inclusive of the recited endpoint. Unless expressly indicated otherwise, the various numerical ranges specified in this application are approximations. The endpoints of all ranges directed to the same component or property are inclusive of the endpoint and independently combinable. The term “from more than 0 to an amount” means that the named component is present in some amount more than 0, and up to and including the higher named amount.
[0020] As used herein, “combinations thereof” is inclusive of one or more of the recited elements, optionally together with a like element not recited, e.g., inclusive of a combination of one or more of the named components, optionally with one or more other components not specifically named that have essentially the same function. As used herein, the term “combination” is inclusive of blends, mixtures, alloys, reaction products, and the like.
[0021] One embodiment of the present invention refers to a washing machine bearing assembly having at least one front bearing and at least one rear bearing spaced apart along a central axis; a spacer at least partially associated with the at least one front bearing and the at least one rear bearing, wherein the spacer includes a plurality of axial fins on the surface of the spacer. The washing machine bearing assembly includes a polymeric housing to house the at least one front bearing, the at least one rear bearing and the spacer, wherein the polymeric housing comprises a negatively drafted seal hub surface and the plurality of axial ribs.
[0022] Referring now to Figure 1, a washing machine bearing assembly 100 according to an embodiment of the present invention, is shown. Figure 1(a) shows the side-front view of the washing machine bearing assembly 100a. Figure 1(b) shows the side-rear view of the washing machine bearing assembly 100b. Figure 1(c) shows the front view of the washing machine bearing assembly 100c. Figure 1(d) shows the sectional view of the washing machine bearing assembly 100d taken along section B-B shown in Figure 1(c). Figure 1(e) shows the rear view of the washing machine bearing assembly 100e.
[0023] As shown in Figure 1, the washing machine bearing assembly 100 includes a polymeric housing 102, at least one front bearing 104, at least one rear bearing 106, a spacer 108, a plurality of axial ribs 110, a plurality of collars 112 and a negatively drafted seal hub surface 114. The polymeric housing 102 encloses the at least one front bearing 104, the at least one rear bearing 106 and the spacer 108. The spacer 108 separates the at least one front bearing 104 and the at least one rear bearing 106. The polymeric housing 102 has plurality of axial ribs 110 on its outer surface, a plurality of collars 112 and the polymeric housing 102 also has a negatively drafted seal hub surface 114.
[0024] Referring to Figure 2, a typical front load washing machine setup 200 as known in the prior art is shown. Figure 2(a) shows the cut view of the washing machine 220. Figure 2(b) shows the cross section of the washing machine 240. The cross section of the washing machine 240 shows the washing machine drum 204 and the washing machine tub 206 along with the washing machine bearing assembly 208 used for driving the washing machine drum 204. Figure 2(c) shows the cross section of the washing machine bearing assembly 260. The cross section of the washing machine bearing assembly 260 shows a housing 212 made out of cast iron, a shaft 214, a seal 210, a front bearing 216 and a rear bearing 218.
[0025] Referring again to Figure 1, in an embodiment of the present invention, the polymeric housing 102 includes a plurality of axial ribs 110. In another embodiment of the present invention, the plurality of axial ribs 110 may be moulded into the polymeric housing 102. The plurality of axial ribs 110 may help to increase the surface area and provides a positive bonding between the washing machine bearing assembly 100 and the washing machine tub. In one embodiment of the present invention the number of ribs making the plurality of axial ribs 110 may be in a range from about 5 to about 50. In another embodiment of the present invention, the number of ribs making the plurality of axial ribs 110 may be in the range from about 10 to about 20. In another embodiment of the present invention, the number of ribs making the plurality of axial ribs 110 may be in the range from about 10 to about 14.
[0026] In an embodiment of the present invention, the polymeric housing 102 further includes a plurality of collars 112. The plurality of collars 112 help to provide a connection and bonding of the washing machine bearing assembly 100 to the washing machine drum.
[0027] In another embodiment of the present invention, the collar is selected from a wing shaped collar, a T-shaped collar or a combination thereof. In an example embodiment of the present invention the collar is a wing shaped collar. In an embodiment of the present invention, the negatively drafted seal hub surface 114 may be a negatively drafted or an inclined/sloped surface to securely fit the seal (not shown) which seals the connection between the washing machine bearing assembly 100 and the washing machine drum. In one embodiment of the present invention, the inclination may be in the range from about 0 degrees to about 3 degrees. Due to the nature of moulding, a good geometric control may be achieved for the negatively drafted seal hub surface 114.
[0028] In an embodiment of the present invention, the seal (not shown) is directly mounted on the polymeric housing 102 by means of the negatively drafted seal hub surface 114. This enables the seal to sit tight on the negatively drafted seal hub surface 114 and not pop-out.
[0029] In an embodiment of the present invention, the washing machine bearing assembly 100 may contain a seal selected from a Garter seal assembly, an O-ring, a mechanical seal, a rubber gasket or a combination thereof.
[0030] In an embodiment of the present invention, the at least one front bearing 104 and the at least one rear bearing 106 may be off the shelf steel bearings.
[0031] In one embodiment of the present invention, the polymeric housing 102 may be made out of a polymer material.
[0032] In an embodiment of the present invention, other materials that can be used for the construction of the polymeric housing 102 include but are not limited to polymers, plastics, ceramics, a composite material, aluminium, metal alloys, a sintered material or a combination thereof.
[0033] In an embodiment of the present invention, the spacer 108 may be made out of a polymer material.
[0034] In another embodiment of the present invention, other materials that can be used for the construction of the spacer 108 include but are not limited to polymers, plastics, ceramics, a composite material, aluminium, metal alloys, a sintered material or a combination thereof.
[0035] In an embodiment of the present invention, the at least one front bearing 104, and the at least one rear bearing 106 may be selected from a ball bearing, a roller bearing, double row angular contact ball bearings, double row tapered roller bearings or a combination thereof.
[0036] In an embodiment of the present invention, the washing machine bearing assembly 100 may contain clearances between the spacer 108 and the at least one front bearing 104 and the at least one rear bearing 106. In an example embodiment of the present invention, the clearances may be in the range of 0 millimetres to 4 millimetres.
[0037] In an embodiment of the present invention, the washing machine bearing assembly 100 may be manufactured using a moulding method. In an embodiment of the present invention, the polymeric housing 102, the at least one front bearing 104, the at least one rear bearing 106 and the spacer 108 may be moulded together. The polymeric housing 102 may be moulded over the at least one front bearing 104, at least one rear bearing 106 and the spacer 108.
[0038] In an embodiment of the present invention, the moulding process is a simplified manufacturing process and reduces the number of steps for manufacturing the washing machine bearing assembly 100. Due to the nature of moulding a good geometric control of the washing machine bearing assembly 100 may be attained. This results in a good alignment between the at least one front bearing 104, at least one rear bearing 106 and the negatively drafted seal hub surface 114. This avoids bearing fitment/mounting issues and leads to better bearing life and reduced system imbalance. Machining of the washing machine bearing assembly 100 may be avoided. Rusting may also be avoided due to the non-metallic nature of polymer. The weight of the polymeric housing 102 may also be reduced when compared to a cast iron housing.
[0039] In an embodiment of the present invention, the washing machine bearing assembly 100 requires fewer parts and simplifies logistics for acquisition.
[0040] In an embodiment of the present invention, the manufacturing process consumes lower energy and thus has reduced environmental impact.
[0041] The polymer and steel interaction between the polymeric housing 102 and the at least one front bearing 104, and the at least one rear bearing 106 may lead to creeping between the polymeric housing 102 and the at least one front bearing 104, and the at least one rear bearing 106. In an embodiment of the present invention, at least one groove may be provided on the outer race surface of the at least one front bearing 104, and the at least one rear bearing 106. In another embodiment of the present invention, at least one groove may be provided on the outer race surface of the at least one front bearing 104, and the at least one rear bearing 106 by means of knurling, to provide an anti-creeping property. This provides a better bond between the polymer material of the polymeric housing 102 and steel material of the at least one front bearing 104, the at least one rear bearing 106. Figure 3 illustrates this through the bearing arrangement 300. The bearing arrangement 300 shows a bearing 302 having at least one groove 304 on the outer race surface 306.
[0042] Figure 4 shows a prior art spacer 400 used in a washing machine bearing assembly. Figure 4(a) shows the spacer 400 with plurality of internal fins 402 and the abutment surface 404. The surface area of the abutment surface 404 for abutting with the at least one front bearing 104 (shown in Figure 1) is limited. The spacer 400 also doesn’t support the axial loads and radial loads acting on the bearing assembly. Figure 4(b) shows a cut view of the spacer shown in Figure 4(a).
[0043] Referring to Figure 5, a spacer 500 according to an embodiment of the present invention, is shown. Figure 5(a) shows the side-front view of the spacer 500a. Figure 5(b) shows the side-rear view of the spacer 500b. Figure 5(c) shows the front view of the spacer 500c. Figure 5(d) shows the sectional view of the spacer 500d taken along section Y-Y shown in Figure 5(c). Figure 5(e) shows the rear view of the spacer 500e.
[0044] In one embodiment of the present invention, the spacer 500 includes a plurality of axial fins 502 on the surface of the spacer 500. In another embodiment of the present invention, the spacer 500 may include a plurality of external fins 502 and / or a plurality of internal fins 504.
[0045] In an embodiment of the present invention, the spacer 500 consists a plurality of external fins 502 located on the outer surface of the spacer 500, a plurality of internal fins 504 located on the inner surface of the spacer 500, a front abutment surface 506 which has an increased surface area for contact with the at least one front bearing 104 (shown in Figure 1) and a rear abutment surface 508 which also has an increased surface area for contact with the at least one rear bearing 106 (shown in Figure 1). The front abutment surface 506 may enable a good abutment between the spacer 500 and the at least one front bearing 104 (shown in Figure 1). The rear abutment surface 508 may enable a good abutment between the spacer 500 and the at least one rear bearing 106 (shown in Figure 1).
[0046] In an another embodiment of the present invention, the front abutment surface 506 and the rear abutment surface 508 may be used as a face area for bearing abutment. The axial loads acting on the bearing assembly 100 may be taken up by the front abutment surface 506 and the rear abutment surface 508, instead of the front face 510 of the plurality of external fins 502 and the rear face 512 of the plurality of external fins 502 respectively.
[0047] In an embodiment of the present invention, the plurality of external fins 502 may be used to support the radial loads in the washing machine bearing assembly 100.
[0048] In an embodiment of the present invention, the spacer 500 may be made up of a polymeric material.
[0049] In another embodiment of the present invention, other materials that can be used for the construction of the spacer 500 include polymers, plastics, ceramics, composites, aluminium, metal alloys, sintered materials or a combination thereof.
[0050] In an embodiment of the present invention, the number of the plurality of external fins 502 may be more than the number of the plurality of internal fins 504.
[0051] In an another embodiment of the present invention, the washing machine bearing assembly 100 may be replicable and used for washing machines of all sizes.
[0052] In an another embodiment of the present invention, the washing machine bearing assembly 100 may be used in a pulley with two pulley bearings on either sides.
[0053] In an another embodiment of the present invention, the washing machine bearing assembly 100 may be used in a roller, for example conveyor belt assembly with two conveyer belt bearings on both sides.
EXAMPLES
[0054] Example 1: The washing machine bearing assembly 100 made up of a polymeric housing 102 to house the at least one front bearing 104, and the at least one rear bearing 106 and a polymer spacer 108 to separate the at least one front bearing 104, and the at least one rear bearing 106. The polymeric housing 102 has a negatively drafted seal hub surface 114, a plurality of collars 112 and a plurality of axial ribs 110. The washing machine bearing assembly 100 is manufactured using moulding. The polymeric housing 102 is made out of a polymer material having a factor of safety range between 2 and 3. The surface area of the outer race surface 306 of the at least one front bearing 104, and the at least one rear bearing 106 when knurled increases the surface area by about 15% to about 25%, when compared with the standard straight outer race surface. The insert moulded manufacturing process compared to the interference fit of the cast iron bearing assembly, increases the bonding area by 15% to 25%. The plurality of axial ribs 110 on the polymeric housing 102 when compared to a housing without the ribs, increases the surface area of the polymeric housing 102 by about 25% to about 35%. The plurality of collars 112 which are wing shaped, when compared to the existing designs that do not have the collars, increases the bond surface area by 50% to 65%.
[0055] In an example embodiment of the present invention, the washing machine bearing assembly 100 having a polymer spacer 108 and a polymeric housing 102 having a plurality of axial ribs 110, a plurality of collars 112 and a negatively drafted seal hub surface 114 provides advantages over the cast iron bearing assembly by increasing the factor of safety, surface bonding areas and incorporating a simpler manufacturing process.
ADVANTAGES
[0056] The technical advantages brought in by the present invention are as follows;
1. The washing machine bearing assembly 100 is eco-friendly as the manufacturing process involve fewer steps and takes less power compared to prior art assembly.
2. The washing machine bearing assembly 100 has lower energy consumptions, improved star rating and reduced environmental impact.
3. The weight of the polymeric housing 102 is lower than the cast iron housing.
4. Better geometry control may be achieved on the negatively drafted seal hub surface 114, as the negatively drafted seal hub surface 114 is a part of polymeric housing 102.
5. Good geometry alignment between the at least one front bearing 104, the at least one rear bearing 106 and negatively drafted seal hub surface 114, results in better bearing life and reduced system imbalance.
6. The polymeric housing 102 does not rust over a period of time.
7. The polymeric housing 102 avoids bearing fitment loss and bearing failure.
8. The plurality of axial ribs 110 on the polymeric housing 102 increases the surface area to support positive bonding between the washing machine bearing assembly 100 and the washing machine tub.
9. The plurality of collars 112 on the polymeric housing 102 enables good connection between the washing machine bearing assembly 100 and the washing machine drum.
10. There is no seal pop out issue, as the seal is mounted directly on polymeric housing 102 by means of the negatively drafted seal hub surface 114.
11. There is no creeping between the polymeric housing 102 and the bearing outer race surface 306.
12. Improved bearing clearance reduction, as the polymeric housing 102 is moulded over the outer race surface 306 and there is less space between the polymeric housing 102 and the at least one front bearing 104 and the at least one rear bearing 106.
13. There is no need for machining as polymeric housing 102 insert moulded over the at least one front bearing 104 and the at least one rear bearing 106.
14. Simplified process steps at washing machine manufacturer’s end.
15. There is less number of parts to be managed by the washing machine manufacturer.
16. Simplified logistics, easy to manage at the washing machine manufacturer’s end.
17. The invention has a flexible design and is easily adaptable to all washing machine sizes and models.
[0057] While considerable emphasis has been placed herein on the components and component parts of the various embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the embodiments without departing from the scope and spirit of the invention. These and other changes in the various embodiment of the disclosure 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.
, Claims:I/We claim:
1. A washing machine bearing assembly comprising:
at least one front bearing and at least one rear bearing spaced apart along a central axis;
a spacer at least partially associated with the at least one front bearing and the at least one rear bearing, wherein the spacer comprises a plurality of axial fins on the surface of the spacer;
a polymeric housing to house the at least one front bearing, the at least one rear bearing and the spacer, wherein the polymeric housing comprises a negatively drafted seal hub surface and a plurality of axial ribs.
2. The washing machine bearing assembly as claimed in claim 1, wherein the at least one front bearing and the at least one rear bearing is selected from a ball bearing, a roller bearing, double row angular contact ball bearings, double row tapered roller bearings or a combination thereof.
3. The washing machine bearing assembly as claimed in claim 1, wherein the at least one front bearing and the at least one rear bearing has at least one groove on the outer race surface of the at least one front bearing and the at least one rear bearing.
4. The washing machine bearing assembly as claimed in claim 1, wherein the spacer is a polymeric spacer.
5. The washing machine bearing assembly as claimed in claim 1, wherein the spacer comprises the plurality of axial fins on the inner surface and the outer surface of the spacer.
6. The washing machine bearing assembly as claimed in as claimed in claim 5, wherein the number of fins in the plurality of axial fins on the outer surface of the spacer is greater than the number of fins in the plurality of axial fins on the inner surface.
7. The washing machine bearing assembly as claimed in claim 1, wherein the plurality of axial ribs on the housing are axial ribs.
8. A washing machine bearing assembly as claimed in claim 1, wherein the number of ribs in the plurality of axial ribs is in a range from about 10 to about 20.
9. The washing machine bearing assembly as claimed in claim 1, wherein the polymeric housing further comprises a plurality of collars wherein the collar is selected from wing shaped collars, T-shaped collars or a combination thereof.
10. A washing machine bearing assembly comprising:
at least one front bearing and at least one rear bearing spaced apart along a central axis;
a spacer at least partially associated with the at least one front bearing and the at least one rear bearing, wherein the spacer comprises a plurality of axial fins on the surface of the spacer;
a housing to house the at least one front bearing, the at least one rear bearing and the spacer; and
wherein the housing is made up of a polymeric material, a plastic material, a ceramic material, a composite material, aluminium, metal alloys or a sintered material or a combination thereof, and the spacer is made up of a polymeric material, a plastic material, a ceramic material, a composite material, aluminium, metal alloys, a sintered material or a combination thereof and the housing comprises a negatively drafted seal hub surface and the plurality of axial ribs.