WO2015149860A1

WO2015149860A1 - Gear arrangement

Info

Publication number: WO2015149860A1
Application number: PCT/EP2014/056743
Authority: WO
Inventors: Marie MINDE; Per KÄLLBERG; Anders WENNERGREN
Original assignee: Electrolux Appliances Aktiebolag
Priority date: 2014-04-03
Filing date: 2014-04-03
Publication date: 2015-10-08

Abstract

A gear arrangement (1) is provided for transferring torque between components (2.1, 2.2) in a dishwasher (3). The gear arrangement (1) comprises a first gear (5) and a second gear (7.1, 7.2), the first gear (5) comprising an annular teeth portion (9) provided with a first set of teeth (11). The first set of teeth (11) of the first gear (5) is arranged to intermesh with a second set of teeth (13) of the second gear (7.1, 7.2). The gear arrangement (1) is arranged to permit a displacement of at least the annular teeth portion (9) of the first gear (5) in a direction away from the second gear (7.1, 7.2). The present invention also relates to a wash arm arrangement (10) and a dishwasher.

Description

GEAR ARRANGEMENT TECHNICAL FIELD

The present invention relates to a gear arrangement, a wash arm arrangement and a dishwasher.

BACKGROUND

Today's dishwashers are expected to perform high quality wash of dishes. Also, environmental concerns require an efficient use of water and energy during a wash cycle. The requirement of performing high quality wash of dish and the requirement of efficient use of water and energy during a wash cycle have led to a development of advanced spray arrangements and wash arm arrangements. One of such arrangements is described in the document US 5464482 A. The arrangement described includes a primary wash arm having at least one secondary wash arm rotatably mounted to one of its ends. During rotation of the primary wash arm within a substantially square washing chamber, the secondary wash arm is rotated so as to extend into corners of the washing chamber during the rotation of the primary wash arm. Thereby, the spray action from the wash arm construction will have a better coverage than a wash arm arrangement as commonly known in the art, i.e. a single wash arm rotating around a single axis so as to create a generally circular spray pattern which does not extend into corners of the washing chamber. However, in order to achieve the above mentioned spray pattern, the wash arm construction requires a transmission to connect rotation of the primary and secondary wash arms. That is, a transmission is needed which ensures that a tip of the secondary wash arm reaches into corners of the dishwasher and do not hit inner walls of a washing chamber of the dishwasher. The environment in a dishwasher puts requirements on such a transmission and such a transmission must be designed such that it is maintenance free and ensures functionality even in a dirty environment.

Therefore, in view of the above, there is a need for an improved gear arrangement for transferring torque between components in a dishwasher. SUMMARY

An object of the present invention is to provide an improved gear arrangement for transferring torque between components in a dishwasher, or to at least provide a useful alternative.

According to an aspect of the invention, the object is at least partly achieved by a gear arrangement for transferring torque between components in a dishwasher, the gear arrangement comprising a first gear and a second gear, the first gear comprising an annular teeth portion provided with a first set of teeth, the first set of teeth of the first gear being arranged to intermesh with a second set of teeth of the second gear, wherein the first gear is ratably arranged to rotate about a first axis of rotation, wherein the gear arrangement is arranged to permit a displacement of at least the annular teeth portion of the first gear in a direction away from the second gear. Since the gear arrangement is arranged to permit a displacement of at least the annular teeth portion of the first gear in a direction away from the second gear, a dirt particle trapped between the first set of teeth and the second set of teeth will, during rotation of the first and second gear, displace at least the annular teeth portion of the first gear away from the second gear. Thereby, the dirt particle is permitted to pass between the first set of teeth and the second set of teeth. As a result, the first gear and a second gear are permitted to continue to rotate. Thereby, the gear arrangement will be less sensitive to disturbances caused by dirt particles. Accordingly, an improved gear arrangement for transferring torque between components of a dishwasher is provided. As a result, the above mentioned object is achieved.

According to some embodiments, the gear arrangement is arranged to permit the displacement by a displacement of the first axis of rotation in a direction away from the second gear. Since the gear arrangement is arranged to permit the displacement by a displacement of the first axis of rotation in a direction away from the second gear, a simple and reliable solution of permitting the displacement is provided. As a result, reliability of the gear arrangement is further improved. According to some embodiments, the first gear comprises at least one resilient member between the annular teeth portion and the first axis of rotation wherein the gear arrangement is arranged to permit the displacement by a displacement of the annular teeth portion of the first gear with respect to the first axis of rotation. Since the first gear comprises at least one resilient member and since the displacement is permitted by a displacement of the annular teeth portion of the first gear with respect to the first axis of rotation, a simple and reliable solution of permitting the displacement is achieved. As a result, reliability of the gear arrangement is further improved. Also, in such embodiments, displacement of the annular teeth portion in a direction away from the second gear can be permitted even with an arrangement where the first axis of rotation of the first gear is firmly attached to a point of attachment. Thereby, reliability of the gear arrangement may be even further improved.

According to some embodiments, the at least one resilient member is a spiral helical spring, leaf spring or the like. In such embodiments, since the at least one resilient member is a spiral helical spring, leaf spring or the like, a simple and reliable solution of providing a resilient member is provided.

The first gear may comprise one or more resilient members, such as two, three or more. The first gear may comprise 2-10 resilient members.

Further embodiments herein aim to provide a wash arm arrangement for a dishwasher, wherein the wash arm arrangement comprises a gear arrangement according to some embodiments. Since the wash arm arrangement comprises a gear arrangement according to some embodiments, an improved wash arm arrangement is provided.

According to some embodiments, the wash arm arrangement comprises a first wash arm arranged to rotate around a second axis of rotation within a washing chamber of the dishwasher, and a second wash arm rotatably arranged on the first wash arm around a third axis of rotation, wherein the third axis of rotation is positioned a distance from the second axis of rotation, and wherein the gear arrangement is arranged to transmit torque between the first wash arm and the second wash arm. Since the gear arrangement is arranged to transmit torque between the first wash arm and the second wash arm, the displacement of at least the annular teeth portion of the first gear in a direction away from the second gear permits the first and second gear to continue to rotate even when a dirt particle is trapped between the teeth of the respective gear. Thereby, also the first wash arm and the second wash arm are permitted to continue to rotate. Accordingly, an improved wash arm arrangement is provided

Further embodiments herein aim to provide a dishwasher comprising a gear arrangement according to some embodiments. Since the dishwasher comprises a gear arrangement according to some embodiments, an improved dishwasher is provided. Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following detailed description. Those skilled in the art will realize that the different features described may be combined to create embodiments other than those described in the following, without departing from the scope of the present invention, as defined by the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The various aspects of the invention, including its particular features and advantages, will be readily understood from the following detailed description and the accompanying drawings, in which;

Fig. 1 illustrates a wash arm arrangement for a dishwasher comprising a gear arrangement according to some embodiments;

Fig. 2 illustrates the gear arrangement, according to some embodiments, and

Fig. 3 illustrates a dishwasher, according to some embodiments.

DETAILED DESCRIPTION

The embodiments herein will now be described more fully with reference to the accompanying drawings. Like numbers refer to like elements throughout. Fig. 1 illustrates a wash arm arrangement 10 for a dishwasher. The wash arm arrangement 10 comprises a gear arrangement 1 . In Fig. 1 , the gear arrangement 1 is illustrated as being arranged to transfer torque between a first wash arm 2.1 and a second wash arm 2.2. However, the gear arrangement provided, may be arranged to transfer torque between other components in a dishwasher, such as between spray nozzles or components such as a wash basket and its attachment point. The gear arrangement 1 comprises a first gear 5 and a second gear 7.1 , 7.2. The first gear 5 comprises an annular teeth portion 9 provided with a first set of teeth 1 1 . The first set of teeth 1 1 of the first gear 5 is arranged to intermesh with a second set of teeth 13 of the second gear 7.1 , 7.2. The gear arrangement 1 is arranged to permit a displacement of the annular teeth portion 9 of the first gear 5 in a direction away from the second gear 7.1 , 7.2. Thereby, a dirt particle (not shown) trapped between the first set of teeth 1 1 and the second set of teeth 13 will, during rotation of the first and second gear 5, 7.1 , 7.2 displace the annular teeth portion 9 of the first gear 5 away from the second gear 7.1 , 7.2. As a result, the first gear 5 and the second gear 7.1 , 7.2 will, as well as the first wash arm 2.1 and the second wash arm 2.2, be able to continue to rotate.

The gear arrangement 1 comprises a first gear 5 and at least a second gear 7.1 , 7.2. As illustrated in Fig. 1 , the gear arrangement 1 may comprise two second gears 7.1 , 7.2 arranged on either side of the first gear 5.

The first gear 5 is ratably arranged to rotate about a first axis of rotation 15. The first gear 5 comprises at least one resilient member 17 between the annular teeth portion 9 and the first axis of rotation 15. The first gear 5 illustrated in Fig. 1 comprises four resilient members. The first gear 5 may comprise any other number of resilient members such as two, three, five or six. The first gear 5 may comprise 2-10 resilient members. The gear arrangement 1 is arranged to permit the displacement by a displacement of the annular teeth portion 9 of the first gear 5 with respect to the first axis of rotation 15. Thereby, a simple and reliable displacement of the annular teeth portion 9, away from the second gear 7.1 , 7.2 is provided. The gear arrangement 1 may be arranged such that a displacement of the annular teeth portion 9, is only permitted in a limited distance. Such limited distance may correspond to a distance which is shorter than a radial extension of a tooth of the first set of teeth 1 1 . Thereby, intermeshing of the first set of teeth 1 1 of the first gear 5 with the second set of teeth 13 of the second gear 7.1 , 7.2 can be ensured even after a displacement of the annular portion 9 of the first gear 5. Thereby, transferring of torque, as well as a rotational relationship between components 2.1 , 2.2, can be ensured even after a displacement of the annular portion 9 of the first gear 5. The displacement of the first gear 5 can advantageously be adapted to be limited to a distance which is 99-5 % of the radial extension of the tooth.

Further, as evident from the design of the first gear 5, after a dirt particle has passed between the first set of teeth 1 1 and the second set of teeth 13, the annular portion 9 of the first gear 5 will return to an initial position, by a biasing force of the at least one resilient member 17. Thereby, functionality of the gear arrangement 1 is further ensured.

As illustrated in Fig. 1 , the wash arm arrangement 10 comprises a first wash arm 2.1 arranged to rotate around a second axis of rotation 19 within a washing chamber of a dishwasher. A second wash arm 2.2 is rotatably arranged on the first wash arm 2.1 around a third axis of rotation 21 . The third axis of rotation 21 is positioned a distance d from the second axis of rotation 19. The gear arrangement 1 is arranged to transmit torque between the first wash arm 2.1 and the second wash arm 2.2.

In addition, the gear arrangement 1 may comprise a wall member (not shown) arranged adjacent to at least the first gear 5 to prevent displacement of the annular portion 9 of the first gear 5 in a direction similar to the direction of the first axis of rotation 15.

Fig. 2 illustrates the gear arrangement 1 , according to some embodiments. The gear arrangement 1 comprises a first gear 5 and at least a second gear 7.1 , 7.2. The first gear 5 comprises an annular teeth portion 9 provided with a first set of teeth 1 1 . The first set of teeth 1 1 of the first gear 5 is arranged to intermesh with a second set of teeth 13 of the second gear 7.1 , 7.2. In these embodiments, the gear arrangement 1 is arranged to permit the displacement by a displacement of the first axis of rotation 15 of the first gear 5 in a direction away from the second gear 7.1 , 7.2. The displacement is achieved by a displacement of the axle upon which the first gear 5 is mounted onto a wash arm or a dish washer. The first gear 5 has a rigid body which comprises the annular teeth portion 9. Further, an attachment of the first gear 5 is biased by a first and a second spring 18.1 , 18.2. Thereby, a dirt particle 20 trapped between the first set of teeth 1 1 and the second set of teeth 13 will, during rotation of the first and second gears 5, 7.1 , 7.2, displace the annular teeth portion 9 of the first gear 5 away from the second gear 7.1 . As a result, the first gear 5 and the second gear 7.1 , 7.2, as well as any components connected thereto, will be able to continue to rotate. Fig. 3 illustrates a dishwasher 3 comprising a washing chamber 27 and a gear arrangement 1 according some embodiments.

Claims

1 . A gear arrangement (1 ) for transferring torque between components (2.1 , 2.2) in a dishwasher (3), said gear arrangement (1 ) comprising a first gear (5) and a second gear (7.1 , 7.2), said first gear (5) comprising an annular teeth portion (9) provided with a first set of teeth (1 1 ), said first set of teeth (1 1 ) of said first gear (5) being arranged to intermesh with a second set of teeth (13) of said second gear (7.1 , 7.2), wherein said first gear (5) is ratably arranged to rotate about a first axis of rotation (15), characterized in that said gear arrangement (1 ) is arranged to permit a displacement of at least said annular teeth portion (9) of said first gear (5) in a direction away from said second gear (7.1 , 7.2).

2. The gear arrangement (1 ) according to claim 1 , wherein said gear arrangement (1 ) is arranged to permit said displacement by a displacement of said first axis of rotation (15) in a direction away from said second gear (7.1 , 7.2).

3. The gear arrangement (1 ) according to claim 1 or 2, wherein said first gear (5)

comprises at least one resilient member (17) between said annular teeth portion (9) and said first axis of rotation (15) wherein said gear arrangement (1 ) is arranged to permit said displacement by a displacement of said annular teeth portion (9) of said first gear (5) with respect to said first axis of rotation (15).

4. The gear arrangement (1 ) according to claim 3, wherein said at least one resilient member (17) is a spiral helical spring, leaf spring or the like.

5. A wash arm arrangement (10) for a dishwasher (3), wherein said wash arm

arrangement (10) comprises a gear arrangement (1 ) according to any one of the preceding claims.

6. The wash arm arrangement (10) according to claim 5, wherein said wash arm

arrangement (10) comprises a first wash arm (2.1 ) arranged to rotate around a second axis of rotation (19) within a washing chamber (23) of said dishwasher (3), and a second wash arm (2.2) rotatably arranged on said first wash arm (2.1 ) around a third axis of rotation (21 ), wherein said third axis of rotation (21 ) is positioned a distance (d) from said second axis of rotation (19), and wherein said gear arrangement (1 ) is arranged to transmit torque between said first wash arm (2.1 ) and said second wash arm (2.2).

A dishwasher (3) comprising a gear arrangement (1 ) according to any one of the claims 1 -4.