Patent Description:
The invention relates to a washing machine.

Washing machines are known. However, they suffer from various disadvantages.

Recently, demands for washing machines that can treat a larger amount of laundry at one time are increasing, but simply expanding a size of a washing machine to meet such demands has limitations in terms of a space in which the washing machine is installed. <CIT> describes a drum type washing machine with a tub for storing washing water which is fixed inside a cabinet with contact to the inner side walls of the cabinet.

<CIT> describes a laundry machine with a rotatable drum placed within a tub for receiving wash water and having a greater up-down direction height than a left-right-direction width.

<CIT> describes a tub of a washing machine, wherein the tub has an elliptic shape.

According to the present invention a washing machine as defined in the appended claims is provided.

<FIG>, <FIG>, and <FIG> show examples of a washing machine useful for understanding the invention, even if not falling under the wording of the appended claims.

The foregoing and other objects, features, aspects and advantages will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. Exemplary embodiments will now be described in detail with reference to the accompanying drawings. Embodiments may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, the exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope to those skilled in the art. In the drawings, the shapes and dimensions may be exaggerated for clarity, and the same reference numerals will be used throughout to designate the same or like components.

In general, a washing machine is an apparatus that uses water, detergent, and mechanical action to wash, for example, clothing, bed linen, etc. (hereinafter referred to as 'laundry') by performing wash, rinse, and spin cycles to remove contaminants from the laundry. Washing machines may be categorized as top loading type and front loading type washing machines according to a laundry loading type.

In front loading type washing machines, a tub may be disposed so as to be rotatable about a horizontal axis, and laundry loaded from a front side. For example, the front loading type washing machine may include a drum washing machine in which laundry is tumbled by a drum rotating about the horizontal axis during washing. A drum washing machine may include a tub installed inside a cabinet that defines an exterior of the washing machine, that holds wash water, and a drum disposed inside the tub to hold laundry, on which wash, rinse, and spin cycles may be performed.

<FIG> is a view of a washing machine. Referring to <FIG>, the washing machine <NUM> may include a cabinet <NUM> that defines an exterior thereof, a tub <NUM> disposed inside the cabinet <NUM> to hold wash water, and a drum <NUM> that rotates inside of the tub <NUM>.

A water supplying passage <NUM> may be provided that supplies wash water into the tub <NUM>. The water supplying passage <NUM> may be equipped with a water supplying valve <NUM> that controls a flow of the wash water.

The tub <NUM> may be spaced from inner side surfaces of the cabinet <NUM>, and may be supported by, for example, suspensions <NUM> and <NUM> and/or a damper <NUM>. In <FIG>, although the tub <NUM> is supported by the suspensions <NUM> and <NUM> disposed at two upper portions thereof and the one damper <NUM> disposed at a lower portion thereof, embodiments are not limited thereto. That is, the tub may be supported by any arrangement, as long as the tub <NUM> is spaced from the inner side surfaces of the cabinet <NUM> and vibration of the tub <NUM> absorbed.

A water exhausting passage <NUM> may be provided, that exhausts wash water out of the washing machine <NUM>. The water exhausting passage <NUM> may be provided with a water exhausting valve <NUM> that controls the flow of wash water and a pump <NUM> that pumps wash water.

A motor <NUM> may provide a driving force that rotates the drum <NUM>. Methods for delivering the driving force provided by the motor <NUM> may be classified into a direct driving method and an indirect driving method. In the direct driving method, a rotational axis of the motor <NUM> may be directly coupled to the drum <NUM>, and the rotational axis of the motor <NUM> and the rotational axis of the drum <NUM> may be coaxially disposed. The motor <NUM> of <FIG> is an example of the direct driving method, where the motor <NUM> is disposed between a rear side of the tub <NUM> and the cabinet <NUM>.

In the indirect driving method, the driving force provided by the motor <NUM> may rotate the drum <NUM> via a power delivery member, such as a belt or a pulley. Alternatively, tubs <NUM>, <NUM>, and <NUM> described hereinbelow may be driven by the indirect driving method. In case of the direct driving method, since there is a limitation in increasing a longitudinal length of the drum <NUM> or the tub <NUM> due to structural limitations of the position of the motor <NUM>, there is a greater need to enlarge the capacity by enlarging a radius of the drum <NUM> or the tub <NUM> or improve space utilization between the tub <NUM> and the cabinet <NUM>, than in the case of the indirect driving method.

The washing capacity is directly related to the capacity of the drum, but the capacity of the tub also needs to increase to enlarge the capacity of the drum. Methods for enlarging the capacity of the tub described hereinbelow are closely related to the enlargement of the drum capacity and the washing capacity.

The tub <NUM> of <FIG> according to <FIG> has a first length in a first direction passing through a central longitudinal axis C of the tub <NUM> and extending substantially horizontally on a certain cross-section substantially orthogonal to the central longitudinal axis C of the tub, and a second length in a second direction passing through the central longitudinal axis C of the tub <NUM> and extending substantially vertically on the certain cross-section. The first length may be shorter than the second length. Hereinafter, referring to <FIG>, the first length may be defined as a horizontal length connecting a point <NUM> to a point <NUM>, and the second length may be defined as a vertical length connecting a point <NUM> to a point <NUM>.

As the tub <NUM> has a certain thickness, a radius of the tub <NUM> may be defined as either a distance from the central longitudinal axis C of the tub <NUM> to an inner side surface of the tub <NUM> or a distance from the central longitudinal axis C of the tub <NUM> to an outer side surface of the tub <NUM>. Hereinafter, for convenience of explanation, the radius of the tub <NUM> may be defined as the distance from the central longitudinal axis C of the tub <NUM> to the outer side surface of the tub <NUM>.

Embodiments disclosed herein improve space utilization in the cabinet <NUM> in consideration of structural characteristics of the cabinet <NUM>, in which the vertical length is longer than the horizontal length. In this regard, since the tub <NUM> has the vertical radius r12h and r6h greater than the horizontal radius r3h and r9h, a capacity of the tub <NUM> may be enlarged though space utilization in the vertical direction inside the cabinet <NUM>, and an interval between an outer side surface of the tub <NUM> and inner side surfaces of the cabinet <NUM> may be secured to prevent the tub <NUM> from colliding with the cabinet <NUM> even when vibration occurs during rotation of the drum <NUM>. Here, collision with the cabinet <NUM> due to vertical vibration of the tub <NUM> has not been considered. This is because the vertical vibration of the tub <NUM> may be directly absorbed by the suspensions <NUM> and <NUM> or the damper <NUM>, and a relatively sufficient space is vertically provided in the cabinet <NUM>, in which to dispose apparatuses, such as the suspensions <NUM> and <NUM>, the damper <NUM>, a detergent box (not shown), and a water supply apparatus (not shown). Accordingly, although the vertical radius of the tub <NUM> is enlarged, collision with the cabinet <NUM> may not occur upon vibration of the tub <NUM>.

In <FIG>, the radius of the tub <NUM> is shown as the distance from the central longitudinal axis C of the tub <NUM> to the outer side surface of the tub <NUM>. In order for the tub <NUM> not to collide with the inner side surface of the cabinet <NUM> when the tub <NUM> vibrates, an interval between the outer side surface of the tub <NUM> and the inner side surface of the cabinet <NUM> may be secured. Accordingly, it will be noted that the terms radius, diameter, and vertical and horizontal widths of the tub <NUM> described hereinbelow are all based on the outer side surface of the tub <NUM>. Generally, since the side walls of the tub <NUM> has a thickness of several mm, for example, about <NUM> or less, there is no substantially significant difference even though the above-mentioned dimensions are defined based on the inner side surface of the tub <NUM>. However, since structures, such as a rib projecting from the outer side surface of the tub <NUM> for stiffness reinforcement, has a thickness of about <NUM> or more, a reinforcing part, such as a rib, may not be disposed at closest portions (<NUM> and <NUM> of <FIG>) to the cabinet <NUM><NUM>. To secure a sufficient interval between the outer side surface of the tub <NUM> and the cabinet <NUM>, a projection length of the rib may also be considered herein.

A curvature of the tub <NUM> may vary in a circumferential direction. More particularly, the curvature may be greater at upper and lower sides than at right and left sides. For example, <FIG> illustrates the tub <NUM> having a greater curvature at the points <NUM> and <NUM> than at the points <NUM> and <NUM>. The curvature of the tub <NUM> may continuously change along the circumference thereof, and the curvature may have a maximum value at the points <NUM> and <NUM> and a minimum value at the points <NUM> and <NUM>. With this structure, the tub has an oval sectional shape with a longer radius r12h and r6h and a shorter radius r3h and r9h. The shorter radius of the tub <NUM> may face a lateral direction of the cabinet <NUM>.

<FIG> is a perspective view of a tub according to an example. <FIG> is a cross-sectional view of the tub of <FIG>.

A tub <NUM> may have a planar surface(s) <NUM> on an outer side surface thereof. At least one of points <NUM> and <NUM> at which a straight line extending along the first direction (<NUM>-<NUM>) meets the outer side surface of the tub <NUM> may be located on the planar surface(s) <NUM>.

The radius of the tub <NUM> may become minimal on the planar surface(s) <NUM>. Accordingly, a horizontal radius r3h and r9h of the tub <NUM> may be smaller than a vertical radius r12h and r6h of the tub <NUM>. In this case, similarly to <FIG>, collision of the tub <NUM> with the cabinet <NUM> may be prevented while improving vertical space utilization inside the cabinet <NUM>. For example, as shown in <FIG>, the tub <NUM> may have planar surfaces (r12h>r3h) at right and left sides based on a circular section thereof. In terms of workability, since the planar surfaces may be formed by slightly modifying an injection mold having a substantially regular circle (radius = r12h) used for a typical tub, it may be advantageous to manufacture such a tub.

However, the tub <NUM> may have a same horizontal radius r3h and r9h and vertical radius r12h and r6h. In this case, although the vertical radius is determined to be equal to the horizontal radius of the tub <NUM>, the tub <NUM> may have a greater capacity than when having a regular circle having the same radius due to the influence of the planar surface(s) <NUM>. The planar surface(s) <NUM> may extend vertically parallel to the inner side surface of the cabinet <NUM>.

Although the cross-section of the tub <NUM> of <FIG> may have a uniform curvature at other locations except the planar surface(s) <NUM>. For example, the curvature of the tub <NUM> may vary such that a space around a corner of the cabinet <NUM> may be further utilized. Points P1 and P2 of <FIG> are two points on the outer side surface of the tub <NUM>, and lines t1 and t2 are tangent lines on the points P1 and P2.

<FIG> is a perspective view of a tub according to an embodiment. <FIG> is a front view of the tub of <FIG>.

Referring to <FIG> and <FIG>, a tub <NUM> may have a first tub member <NUM> disposed at a front side of the tub <NUM> and a second tub member <NUM> disposed at a rear side of the tub <NUM>. A cross-section of the tub <NUM> of <FIG> may be similar to that shown in <FIG>, but embodiments are not limited thereto. For example, the tub <NUM> may be formed by combining two tubs, which are divided into the front side and the rear side, and thus, the tub <NUM> may have a cross-section similar to those of the tubs described with reference to <FIG> or derivatives thereof.

More particularly, the tub <NUM> according to this embodiment may have a planar surface(s) <NUM> similarly to the previous embodiment. A first portion <NUM> of the planar surface <NUM> may be formed on the first tub member <NUM>, and a second portion <NUM> of the planar surface <NUM> may be formed on the second tub member <NUM>.

The tub <NUM> may be formed by injection-molding. An outer side surface of the first tub member <NUM> and/or the second tub member <NUM> may be inclined in the longitudinal direction, such that demolding may be smoothly performed upon injection-molding. In this case, a bonding line PL, at which the first tub member <NUM> and the second tub member <NUM> meet, may be an outermost circumference of the tub <NUM>. In <FIG>, an angle a may be an angle between a tangent line tf on a front end of the first tub member <NUM> and a central longitudinal axis C, and an angle b may be an angle between a tangent line tr on a rear end of the second tub member <NUM> and the central longitudinal axis C.

The first planar portion <NUM> formed on the first tub member <NUM> of the planar surface <NUM> may have a minimum width at the front end of the first tub member <NUM>, and may have a maximum width at the rear end defining the bonding line PL. The second planar portion <NUM> formed on the second tub member <NUM> may have a maximum width at the front end of the second tub member <NUM> defining the bonding line PL, and may have a minimum width at the rear end of the second tub member <NUM>.

More specifically, due to the inclined shape of the first tub member <NUM> and/or the second tub member <NUM>, a distance from the central longitudinal axis C of the tub <NUM> may become maximum at the bonding line PL at which the first tub member <NUM> and the second tub member <NUM> meet, and may become minimum at the front end of the first tub member <NUM> or the rear end of the second tub member <NUM>. However, any point taken from the planar surface <NUM> may be spaced from a certain vertical plane that spans along a longitudinal direction of the tub <NUM> by the same distance, because at least one of the first tub member <NUM> or the second tub member <NUM> may be substantially parallel to the vertical plane.

The first tub member <NUM> and the second tub member <NUM> may be mutually coupled to each other by, for example, beading, but an interval between the tub <NUM> and the cabinet <NUM> may be reduced due to the projecting bonding line PL. Accordingly, the first tub <NUM> and the second tub member <NUM> may be coupled to each other by, for example, thermal bonding method. Even if the first tub <NUM> and the second tub member <NUM> are coupled by beading, the thermal bonding method may be performed at least on the planar surface(s) <NUM>.

Although, according to embodiments, it has been described that the shape of the tub is vertically symmetrical (r12h=r6h) based on the horizontal line <NUM> to <NUM> and is horizontally symmetrical (r3h= r9h) based on the vertical line <NUM> to <NUM>, embodiments are not limited thereto, but may be modified within the scope to be described through each embodiment.

In the above disclosed embodiments, the tub may be formed to have a different vertical radius (r12h= r6h) and horizontal radius (r3h and r9h). More particularly, the vertical radius (r12h= r6h) may be greater than the horizontal radius (r3h and r9h), such that the capacity of the tub may be enlarged through vertical space utilization inside the cabinet <NUM>. In this case, a vertical diameter may be greater than a horizontal width of the cabinet <NUM>.

Embodiments disclosed herein provide a washing machine, which may expand capacity by improving internal space utilization of a cabinet. Further, embodiments disclosed herein provide a washing machine, which may sufficiently deal with vibration generated during rotation of a drum while enlarging a capacity of the drum, and more particularly, may secure a sufficient absorbing space between a tub and a cabinet.

Embodiments disclosed herein provide a washing machine that includes a cabinet that defines an exterior of the washing machine, and a tub disposed inside the cabinet to hold wash water. The tub may have a cross-section for which a first length that passes a center of the tub and extends from one or a first side to the other or a second side along a first direction, which is substantially horizontal, may be shorter than a second length that passes the center of the tub and extends from one or a third side to the other or a fourth side along a second direction, which is substantially perpendicular to the first direction.

Embodiments disclosed herein further provide a washing machine that include a cabinet that defines an exterior of the washing machine, and a tub disposed inside the cabinet to hold wash water. The tub may have a straight line section on at least a portion of a cross-section orthogonal to a longitudinal direction of the tub, and at least one of both points at which a straight line passing a center of the tub and extending along a first direction, which is substantially horizontal, meets an outer side surface of the tub is located on the straight line section.

Claim 1:
A washing machine (<NUM>) comprising:
a cabinet (<NUM>) defining an exterior of the washing machine (<NUM>);
a tub (<NUM>) disposed in the cabinet (<NUM>) and configured to hold wash water; and
a drum (<NUM>) rotatably disposed in the tub (<NUM>);
wherein the tub (<NUM>) extends along a direction parallel to a rotational axis of drum and includes:
a first tub member (<NUM>) forming a front side of the tub (<NUM>);
a second tub member (<NUM>) forming a rear side of the tub (<NUM>) and coupled to the first tub member (<NUM>); and
a planar surface (<NUM>) having a first planar portion (<NUM>) formed on the first tub member (<NUM>), and a second planar portion (<NUM>) formed on the second tub member (<NUM>);
wherein the first planar portion (<NUM>) has a minimum width at a front end of the first tub member (<NUM>) and a maximum width at a rear end of the first tub member (<NUM>) defining a bonding line (PL) at which the first tub member (<NUM>) and the second tub member (<NUM>) meet; and the second planar portion (<NUM>) has a minimum width at a rear end of the second tub member (<NUM>) and a maximum width at a front end of the second tub member (<NUM>) defining the bonding line (PL).