AU722706B2

AU722706B2 - Improved direct drive washing machine

Info

Publication number: AU722706B2
Application number: AU67988/98A
Authority: AU
Inventors: Dong-Beom Lee; Young-Bok Park
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 1997-10-27
Filing date: 1998-05-20
Publication date: 2000-08-10
Anticipated expiration: 2018-05-20
Also published as: KR19990033908A; JP3068054B2; KR100245291B1; JPH11137890A; AU6798898A

Description

Our Ref. 680077 P/00/OII Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAIL

COMPLETE SPECIFICATION STANDARD PATENT *0 S

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Applicant(s): LG Electronics Inc.

20, Yoido-dong Youngdungpo-gu Seoul 150-721 REPUBLIC OF KOREA (SOUTH) DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Address for Service: :t A~ fCr.~o~Jr~ ki4~eA &e-~4D4e~ 1 44 6

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Invention Title: wahing fflGij The following statement is a full description of this invention, including the best method of performing it known to me: 5020 P:\WPDOCS\DYS\SPECIE\680077sp.doc-29/05/00 -1- IMPROVED DIRECT DRIVE WASHING MACHINE BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a direct drive washing machine. More particularly, it relates to no clutch type direct drive washing machine which stably supports a drive shaft for connecting an agitator, an insulator, a hub, and an electric motor's rotor to each other, and a water tub of the washing machine, and forms a perfect seal with a relatively small number of components, thus reducing the number of assembly processes and lowering the overall production costs.

Discussion of Related Art A conventional washing machine is depicted in FIG. 1.

.o o The conventional washing machine includes a laundry tub 5a rotatably mounted in a water tub 2a of a main body la; an agitator 51 installed on the bottom of the inside of the 20 laundry tub 5a; a dehydration shaft 53 and a shaft 54 of a clutch 52, disposed on the bottom of the water tub 2a, each connected to the laundry tub 5a and the agitator 51 passing ttherethrough; a motor pulley 55 and a clutch pulley 56 each provided to a motor 41a, disposed on one side under the water tub 2a, and the clutch 52; and a V belt 57 interposed between the motor pulley 55 and the clutch pulley 56.

As shown in FIG. 2, the clutch 52 includes a spring block 59 disposed under a gear.

shaft 58 directly receiving power from the clutch pulley 56 of the, clutch 52, and a first clutch spring 61 formed integrally with the upper shaft 53 and a brake housing 60 at the outer surface of the lower dehydration shaft 53a.

A clutch boss 63 with a cogged portion 62 is provided to the outer surface of the first clutch spring 61, and a cam 65 is rotatably provided to a lower portion of a lever 64 interlocking a drain valve-cum-solenoid valve (not shown), installed on one side of the water tub 2a, to be connected with the cogged portion 62 of the clutch boss 63. A one-way clutch 66 is mounted over the upper portion of the gear housing 60 to prevent backward rotation of the laundry tub 5a. A planetary gear 67 is installed within the gear housing for reducing and transmitting the power of the gear shaft 58 to the shaft S 54 during operation, and a brake band 68 is mounted on the outer surface of the brake drum-cum-gear housing When a full automatic washing machine performs the washing task, the o. laundry tub 5a remains stationary, and the agitator 51 agitates clothes for laundering. When it performs the dehydration task, the laundry tub 5a and the agitator 51 rotate at the same full speed. As shown in FIGS. 1 and 2, the forward rotating force of the motor 41a to the clutch 56 via the V belt 57, acts in the direction of winding the first clutch spring 61 and must be transmitted to the lower dehydration shaft 53a, and the cam 65 pushes the first clutch spring 61 engaging with the cogged portion 62 of the clutch boss 63 installed on the outer surface of the first clutch 61, thus preven ting winding of the first clutch spring 61 and power transmission to the dehydration shaft 53a. The rotating force transmitted to the gear shaft 58 is reduced via the planetary gear 67 within the brake drum-cum-gear housing and sent to the shaft 54 to rotate the agitator 51 joined to the shaft 54 for laundering.

Since the backward rotating force of the motor 41a acts in the direction of unwinding the first clutch spring 61, and the torque of the gear shaft 58 cannot be sent to the dehydration shaft 53. the torque is reduced by the r; planetary gear 67 to be transmitted to the shaft 54, thus rotating the agitator 51 joined to the shaft 54.

When the torque is reduced by the planetary gear 67, a reactive torque is created at the gear housing 60, and the rotation of the dehydration shaft 53 is prevented by the one-way clutch 66, serving to prevent the backward rotation of the dehydration shaft 53, and the brake band 68, mounted on the outer surface of the brake drum-cum-gear housing 60 by a predetermined pressure. The rotating force of the motor 41a, sent to the clutch 52 via the V belt 57, acts in the forward direction of winding the first clutch spring 61 so that the first clutch spring 61 comes in close contact with the spring block 59 and the drain valve-cum-solenoid valve is turned on to pull the brake lever 69. Simultaneously with this, the cam 65 of the lever 64 interlocking the brake lever 69 is dislocated from the cogged portion 62 of the clutch boss 63. As the brake band 68 is removed from the outer surface of the gear housing 60, the rotating force of the spring block 59 makes the gear housing 60 and the upper dehydration shaft 53, integrally formed with the Si'. gear housing 60, rotate in one way at high speed, thus performing the dehydration task.

When the dehydration operation is completed or stops by force in the middle thereof, the drain valve-cum-solenoid valve is turned off to release the lever 64, and the cam 65 is caught between the clutch boss 63 and the cogged portion 62. As the brake band 68 compresses the outer surface of the gear housing 60 and converts the dehydration mode into a laundering mode, thus stopping the rotation of the gear housing 60, the laundry tub connected to the gear housing 60 and the upper dehydration shaft 53, stops, too.

In the driving mechanism of the conventional full automatic washing machine, the motor 41a and the clutch 52 are separately disposed to transmit P: WPDOCS\fYS\SPECIE\680077p.doec-29/051 -4the power of the motor 41a to the clutch 52 via the V belt 57, and the overall construction is too complicated. In addition, the clutch 52 which controls and reduces the rotating force during operation is also complicated in construction to cause a loss of the rotating force at the time of transmitting the rotating force via the V belt 57. The agitator 51 generates water currents to perform laundering, and the water currents are principally created in the lower section of the laundry tub 5a, not circumferentially, which causes the clothes being washed to be twisted and get damaged.

SUMMARY OF THE INVENT ION According to one aspect of the present invention there is provided a direct drive washing machine including Sa water tub for containing a washing fluid said water tub including a base wall; :a laundry tub positioned within said water tub, said laundry tub including an agitator, said laundry tub and agitator being arranged in one mode of operation for rotational o o° movement in an agitating fashion and in another mode of operation for rotational movement in a full rotating fashion.

a bearing support assembly operatively connected to the water tub and including a Q cylindrical body which extends through the water tub and has upper and lower bearing mountings for respective upper and lower bearings; a variable speed motor which includes a stator operatively connected to the bearing support assembly, a rotor and a drive shaft for rotating the laundry tub, the drive shaft being supported by said bearings, a hub connected to the drive shaft, said hub being operatively connected to and supporting the laundry tub; said bearing support assembly further including first sealing means disposed between 4 1.4i drive shaft and an upper portion of the cylindrical body; and P:\WPDOCS\DYS\SPECIE\680177spc.doc-29/05A/0 second sealing means disposed between the cylindrical body and the water tub.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE ATTACHED DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the drawings: In the drawings: 0 OS S FIG. 1 is a cutaway sectional view of a bearing housing coupling structure for a *00 0.0 20 conventional washing machine; 00 S FIG. 2 is a sectional view of no clutch type direct drive washing machine in I ,accordance with a first preferred embodiment of the present invention; 0 FIG. 3 is an enlarged-sectional view of no clutch type direct drive washing machine of FIG. 2; P:\WPDOCS\DYS\SPECIE680077spedoc-29/05AMH -6- FIG. 4 is a sectional view of a main part of a washing machine in accordance with a second preferred embodiment of the present invention; FIG. 5 is a sectional view of a main part of a washing machine in accordance with a third preferred embodiment of the present invention; FIG. 6 is a sectional view of a main part of a washing machine in accordance with a fourth preferred embodiment of the present invention; and FIG. 7 is a sectional view of a main part of a washing machine in accordance with a fifth preferred embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

Referring to FIGS. 3 to 7, no clutch type direct drive washing machine includes bearing housing 161 disposed under the middle of a water tub 171, and a driving motor 191 mounted under the bearing housing 161 for turning a drive shaft 141 mounted within the 25 bearing housing and coupled to the hub rotating a hub 131, an insulator 121, and a laundry tub 102.

To prevent water of the water tub 171 from getting into a space between an upper coupling element 167 of the bearing housing 161 and the upper section of the drive shaft 141, there is provided a first sealing member 181 consisting of an outer seal 183, attached to 9 9 9 9.

9 9 *9 9 9*99 0 8* 99~i* *r 9 99* 9 -1' \~tn Qt/ P:\WPDOCS\DYSSPECIE680077spe.do-29/05A -7an inner surface of the upper coupling element 167, and an inner seal 182 adhering to an outer surface of the drive shaft 141.

A seal core 184 is coupled to the outer seal 183 of the first sealing member 181 in order that the outer seal 183 of the first sealing member 181 elastically supports the inner surface of the upper coupling element 167 of the bearing housing 161. The seal core 184 is made of metal.

To make the inner seal 182 of the first sealing member 181 closely contact the drive shaft 141, an elastic member 186 is provided to elastically support the outer surface of the inner seal 182. An auxiliary seal 185 is formed extending to the outside of the outer seal 183 in order that the outer seal 183 of the first sealing member 181 encloses the upper coupling element 167 of the bearing housing 161 to form a seal. The upper coupling element 167 is interposed between the outer seal 183 and the auxiliary seal 185 of the first sealing member 15 181, and an extending portion 173 of the water tub 171 comes in close contact with the outer :o surface of the auxiliary seal 185. An upper bearing mounting 164 is provided to the upper :i portion of the bearing housing 161 to support an upper bearing 201, thus distributing load, applied to the drive shaft 141, to the bearing housing 161. A lower bearing mounting is disposed under the bearing housing 161 to be supported by a lower bearing 202 so that the lower bearing 202, joined to the drive shaft 141, is located at an exact position to securely 03 support the drive shaft 141.

.0 A nut 196 mates into a screw portion 146 of the drive shaft 141 so that the upper and lower bearings 201 and 202 are sealed by the upper and lower projecting portions 144 and 25 145 of the drive shaft 141 and the upper and lower bearing mountings 164 and 165 not to freely move. A fixing groove 170 is formed at the bottom of the bearing housing 161, and a projection 199 is provided to a stator 193 for being fit into the fixing groove 170 in order to accurately fix the stator 193 of the driving motor 191, joined to the bottom of the bearing housing 161 via a bolt 197, to the drive shaft 141. A support rise 194 is provided to the stator 193 connected to a lower section of the lower bearing for coaxially joining the stator 193 and the rotor 192 of the driving motor 191 to each other. Referring to FIG. 6, an P:\WPDOCS DYS\SPECIEM690O77spe.doc-29A)$AI -8extending piece 166 is formed extending to the lower portion of the bearing housing 161, and an insertion piece 198 is provided to the stator 193 inwardly engaging with the extending piece 166 so as to coaxially join the stator 193 and the rotor 192 of the driving motor 191 to each other. Referring now to FIG. 7, an extending piece 166 is formed extending to the lower portion of the bearing housing 161, and an insertion piece 198 may be provided to the stator 193 outwardly engaging with the extending piece 166.

A flange 162 is radially provided to the bearing housing 161, and coupling holes 163 are formed at the flange 162, through which bolts 203 are each screwed into bosses 172 of the water tub 171 in a such a way that the bearing housing 161 is fixed to the bottom of the water tub 171. Some of the bolts 203 are used to fasten a motor cover 221 to the bottom of the water tub 171 with the flange 162 of the bearing housing 161. A second sealing member 211 is fixedly interposed between a supporting surface 169 formed at an outer surface of the bearing housing 161, and a sealing rib 174 of the water tub 171 to prevent the water from 15 leaking out to a gap between the bearing housing 161 and the water tub 171. An outer spline :147 is provided to the drive shaft 141 and an inner spline 195 is provided to the rotor 192 to 000.0 be coupled with the outer spline 147 so as to correctly join the rotor 192 of the driving motor i 191 to the drive shaft 141 to receive the rotating force.

4.

To prevent the water from getting into the upper coupling element 167 of the bearing housing 161, the upper coupling element 167 is protruded to be higher than the bottom of the water tub 171, and a circumferential rib 139 is provided to the hub 131 extending to the middle of the upper coupling element 167 surrounding the element 167 for forming an air layer inside the upper coupling element 167.

ooo: The following description relates to the operation of the present invention.

Once pressing a starting button after putting garments to be cleaned in the laundry tub 102 of the washing machine 101, water is furnished to the laundry tub 102. When the water in the laundry tub 102 reaches to a predetermined level, the water supply is cut off to drive the driving motor 181. As the rotor 192 is rotated by the driving motor 181, the

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P:\WPDOCS\DYS\SPECIE6gO0077sp.do-29105fO -9rotating force of the drive shaft 141 rotates the hub 131, the insulator 121, the agitator 111, and the laundry tub 102. The garments being washed are tumbled and agitated by wings 112 of the agitator 111. As the drive motor 191 directly rotates the drive shaft 141 mounted within the bearing housing and coupled to the hub 161 of the water tub 171, the rotating force is directly applied to the hub 131, the insulator 121, and the laundry tub 102, thereby minimizing power loss. The water in the water tub 171 cannot get into a gap between the upper coupling element 167 of the bearing housing 161 and the upper section of the drive shaft 141 by the first sealing member 181 having the outer seal 183, attached to the upper coupling element 167 of the bearing housing 161, and the inner seal 182 adhered to the outer surface of the drive shaft 141' s upper section, as shown in FIGS. 3 and 4.

The outer seal 183 of the first sealing member 181 elastically is attached to the inner side wall of the upper coupling element 167 of the bearing housing member 181. Since the seal core 184 is made of metal, the outer seal 183 closely contacts the inner surface of the 15 upper coupling element 167 to form a perfect seal.

I: '"The inner seal 182 of the first sealing member 181 is configured for close contact with the drive shaft 141 by the elastic member 186 elastically attaching to the outer surface of the inner seal 182. The outer seal 183 of the first scaling member 181 forms a seal surrounding the upper coupling element 167 of the bearing housing 161 by the auxiliary seal 185 extending to the outside of the outer seal 183. The upper coupling element 167 of the bearing housing 161 is inserted between the first sealing member 181's outer seal 183 and i auxiliary seal 185, and the extending portion 173 of the water tub 171 is adhered to the outer surface of the auxiliary seal 185, thus forming a secure seal.

S" The load applied to the drive shaft 141 is distributed to the bearing housing 161 by the upper bearing mounting 164, provided to the upper section of the bearing housing 161 for supporting the upper bearing 201, thus making the drive shaft 141 more stable. The lower bearing 202 is joined to a right position of the drive shaft 141 by the lower bearing mounting 165 provided to the lower section of the bearing housing 161 being in supporting PA WPDOCSDYS\SPECIE( 80077T.A-29/05MD engagement with the lower bearing 202, thus more securely supporting the drive shaft 141 for correct rotation.

The upper and lower bearings 201 and 202 each come in close contact with the upper and lower projecting portions 144 and 145 of the drive shaft 141 and the upper and lower bearing mountings 164 and 165 by the nut 196 mating into the screw portion 146 of the drive shaft 141 so that they do not freely move.

The stator 193 of the driving motor 191, joined to the bottom of the bearing housing 161 via the bolt 197, is correctly affixed to the drive shaft 141 by the use of the fixing groove 170 and the projection 199, each provided to the lower portion of the bearing housing 161 and the stator 193. The stator 193 and the rotor 192 of the driving motor 191 are coaxially joined to each other by the support rise 194 provided to the stator 193 and by the extending piece 166 extending to the lower portion of the bearing housing 161, and the 15 insertion piece 198 provided to the stator 193 inwardly engaging with the extending piece o 166 (FIG. The stator 193 may be coaxially joined to the rotor 192 by the extending piece 166 extending to the lower portion of the bearing housing 161, and the insertion piece 198 provided to the stator 193 outwardly engaging with the extending piece 166 (FIG. 7).

The flange 162 is radially provided to the bearing housing 161, and the coupling holes 163 are formed at the flange 162, through which the bolts 203 are each screwed into the bosses 172 of the water tub 171 for fastening in a manner that the bearing housing 161 is 9@i S fixed to the bottom of the water tub 171. A part of the bolts 203 are used to fasten the motor cover 221 to the bottom of the water tub 171 with the flange 162 of the bearing housing 161, which decreases the number of the assembly steps. The second sealing member 211 is fixedly interposed between the supporting surface 169, formed at an outer surface of the bearing housing 161, and the sealing rib 174 of the water tub 171 to prevent the water from leaking out to a gap between the bearing housing 161 and the water tub 171. The outer spline 147 is provided to the drive shaft 141 and the inner spline 195 is provided to the rotor 192 to be coupled with the outer spline 147 so as to correctly join the rotor 192 of the driving motor 191 to the drive shaft 141 to receive the rotating force.

_!VT P:\WPDOCS\IDYS\SPECIE\(80(7sp.d-29OA)lO -11- The upper coupling element 167 is protruded to be higher than the bottom of the water tub 171, and the circumferential rib 139 is provided to the hub 131 extending to the middle of the upper coupling element 167 surrounding the element 167 for the purpose of forming an air layer inside the upper coupling 0 *0 *0a* 0e 0* 0~ 0 0 0 0 0 0: 0*0* 0 0 0.* 0e 0 0 0 0 0 0 00.0 00 00 0 0 element 167, which prevents the water from getting into the upper coupling element 167 of the bearing housing 161.

As described above, the present invention simplifies the driving mechanism, thus preventing mechanical breakdowns due to the complicated structure and lowering the overall production costs. A perfect seal is formed between the water tub and the bearing housing, and between the bearing housing and the drive shaft alike. This prevents the water from getting into the driving motor, and lets the rotating force of the motor be directly transmitted to the laundry tub, thereby minimizing the power loss and enhancing the laundering efficiency.

Q "It will be apparent to those skilled in the art that various modifications and variations can be made in the inventive washing machine without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Claims

1. A direct drive washing machine including a water tub for containing a washing fluid said water tub including a base wall; a laundry tub positioned within said water tub, said laundry tub including an agitator, said laundry tub and agitator being arranged in one mode of operation for rotational movement in an agitating fashion and in another mode of operation for rotational movement in a full rotating fashion. a bearing support assembly operatively connected to the water tub and including a cylindrical body which extends through the water tub and has upper and lower bearing mountings for respective upper and lower bearings; a variable speed motor which includes a stator operatively connected to the bearing support assembly, a rotor and a drive shaft for rotating the laundry tub, the drive shaft being supported by said bearings, a hub connected to the drive shaft, said hub being operatively connected to and supporting the laundry tub; said bearing support assembly further including first sealing means disposed between qo the drive shaft and an upper portion of the cylindrical body; and second sealing means disposed between the cylindrical body and the water tub.

2. A direct drive washing machine in claim 1 wherein said hub has circumferential rib 20 extending from an underside thereof to a position below the first sealing means.

3. A direct drive washing machine in claim 2 wherein said circumferential rib surrounds an upper portion of the cylindrical body.

4. A direct drive washing machine in claim 1 wherein said lower bearing is mounted by a nut meshed with a screw portion of the drive shaft.

5. A washing machine substantially as hereinbefore described with reference to the accompanying drawings. C Dated this 2 9 th day of May, 2000 LG ELECTRONICS INC. By Its Patent Attorneys __AVIES COLLISON CAVE