WASHING MACHINE

Abstract

Disclosed is a washing machine. The washing machine includes: a machine housing; a washing tub having an inner tub which accommodates laundry and is rotatable and an outer tub for receiving the inner tub, and being provided inside the machine housing; four supporting members, which are configured to be in a shape of a rod suspended from the machine housing and elastically support the washing tub; and receiving portions, which are mounted at the lower portion of each of the supporting members respectively to connect the supporting members to the washing tub. All the receiving portions are provided at the same height. The length of a pair of front supporting members and that of a pair of rear supporting members are different.

Description

TECHNICAL FIELD

The present disclosure relates to a washing machine.

BACKGROUND

In a washing machine described in the following Patent Document 1, an outer tub is supported by four hanging rods inside a machine frame, a washing and dehydrating tub is rotatably supported inside the outer tub, and a pulsator for agitating the laundry is provided at the bottom of the washing and dehydrating tub. The rotational power of a motor attached to a lower surface of the outer tub is transmitted to the washing and dehydrating tub and the pulsator. A lower end of the hanging rod is fixed to a mounting piece protruding from the bottom wall of the outer tub, and an upper end of the hanging rod is held by a hanging rod receiving metal that is fixed to a mounting piece protruding inward from the machine frame. The vibration of the outer tub in the case of the dewatering process of the washing operation or the like is absorbed by a compression spring that is provided at the top end of the hanging rod as a vibration-proof body.

The washing machine described in Patent Document 1 has the following hidden danger: when a braking is applied to the rotation of the washing and dehydrating tub to stop the dehydrating process, the outer tub may vibrate greatly due to the bias of the laundry in the washing and dehydrating tub, and four hanging rods cannot completely inhibit the vibration of the outer tub, causing the outer tub to collide with the machine housing of the washing machine.

EXISTING ART LITERATURE

Patent Literature

Patent Literature 1: Japanese Laid-Open Patent Publication No. 2001-137592

SUMMARY

The present disclosure has been made based on the above background, and an object of the present disclosure is to provide a washing machine capable of preventing a washing tub provided in a machine housing from vibrating and colliding with the machine housing.

The Solution to the Problem

The present disclosure relates to a washing machine. The washing machine includes a machine housing; a washing tub having an inner tub which accommodates laundry and is rotatable and an outer tub for receiving the inner tub, and being provided inside the machine housing; four supporting members, which are configured to be in a shape of a rod suspended from the machine housing and elastically support the washing tub; and receiving portions, which are mounted at the lower portion of each of the supporting members respectively to connect the supporting members to the washing tub. All the receiving portions are provided at the same height, and among the four supporting members, the length of a pair of supporting members and the length of another pair of supporting members are different.

In addition, the present disclosure is characterized in that the washing tub is capable of rotating in a manner of crossing with a vertical direction.

Effect of the Invention

According to the present disclosure, the four support members formed in a shape of a rod suspended from the machine housing are connected to the washing tub by the receiving portions attached to the lower portions of the four support members, respectively, such that the support members elastically support the washing tub provided inside the machine housing. All the receiving portions are provided at the same height. Among the four supporting members, the length of a pair of supporting members and the length of another pair of supporting members are different. When such a structure is adopted, the vibration of the washing tub is effectively suppressed by the four supporting members when the inner tub of the washing tub is rotating during the dewatering process of washing operation or when a braking is applied to the rotation of the inner tub for stopping the dewatering process, thereby suppressing the vibration of the washing tub and its collision with the machine housing.

In addition, according to the present disclosure, the washing tub is capable of being rotated in a manner of crossing with a vertical direction. With a washing machine having the above-mentioned structure, the vibration of the washing tub can be suppressed through the four supporting members, and thus, the present disclosure can suppress the vibration of the washing tub and its collision with the machine housing.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a left view of a main portion of a washing machine according to an embodiment of the present disclosure.

FIG. 2 is a schematic longitudinal sectional view of a main portion and a peripheral portion of a supporting member of the washing machine.

FIG. 3 is a schematic left view of the main portion of the washing machine.

FIG. 4 is a diagram showing a relationship between an amplitude of the vibration of an outer tub of the washing tub generated along with the rotation of an inner tub during the dewatering process and a length difference between a front supporting member and a rear supporting member.

FIG. 5 is a diagram showing a relationship between an amplitude of the vibration of the outer tub generated along with the termination of rotation of the inner tub at the end of the dewatering process and a length difference between a front supporting member and a rear supporting member.

FIG. 6 is a left view of a washing machine in a modified example.

A LIST OF REFERENCE NUMERALS

1: Machine housing; 2: Washing tub; 3: Outer tub; 4. Inner tub; 7: Supporting member; 7A: Front supporting member; 7B: Rear supporting member; 18: Receiving portion; 100: Washing machine; Z: Up-down direction

DETAILED DESCRIPTION

The embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. FIG. 1 is a left view of a main portion of a washing machine 100 according to an embodiment of the present disclosure. The up-down direction in FIG. 1 is referred to as an up-down direction Z of the washing machine 100, the left-right direction in FIG. 1 is referred to as a front-rear direction Y of the washing machine 100, and a direction perpendicular to the paper surface in FIG. 1 is referred to as a left-right direction X. The up-down direction Z is a vertical direction. Regarding the up-down direction Z, the upper side is referred to as an upper side Z1, and the lower side is referred to as a lower side Z2. Regarding the front-rear direction Y, the right side of FIG. 1 is referred to as a front side Y1, and the left side of FIG. 1 is referred to as a rear side Y2. Regarding the left-right direction X, the surface side of the paper surface in FIG. 1 is referred to as a left side X1, and the inner side of the paper surface in FIG. 1 is referred to as a right side X2.

The washing machine 100 includes a washing and drying machine that has a laundry drying function. However, in the following, the washing machine 100 will be described with an example of the washing machine in which the laundry drying function is omitted and only the washing operation is performed. The washing operation includes a washing process, a rinsing process and a dewatering process. The washing machine 1 includes a machine housing 1 constituting an outer shell of the washing machine. Inside the machine housing 1, a washing tub 2 that is, an outer tub 3 and an inner tub 4 constituting the washing tub 2, a motor 5, a transmission mechanism 6 and a supporting member 7 are arranged.

The machine housing 1 includes a metal outer frame 10 and a decorative cover 11, and as a whole is formed in a substantially box-like shape. The outer frame 10 constitutes a frame of the machine housing 1, and the decorative cover 11 is fixed to the outer frame 10 in a manner of covering the outer frame 10 from the outside. It should be noted that, for the convenience of explanation, in FIG. 1, the outer frame 10 is shown by a dotted line, and at least one part of the decorative cover 11 is shown by a dash-dot line (FIG. 6, which is to be mentioned later, also relates to the above case).

The outer frame 10 integrally includes a total of four vertical columns 12 that are arranged one by one at four corners of the machine housing 1 in plan view from the upper side Z1 and extend in the up-down direction Z. An upper horizontal strut 13 is bridged between upper ends of two vertical columns 12 that are arranged one after another in the front-rear direction and extends in the front-rear direction Y, and a lower horizontal strut 14 is bridged between lower ends of the two vertical columns 12 that are arranged one after another in the front-rear direction and extends in the front-rear direction Y. Although not shown, the outer frame 10 further includes a horizontal strut that is bridged between the two vertical columns 12 that are arranged side by side in the left-right direction and extends in the left-right direction X.

Each of the vertical columns 12 does not necessarily have to extend straight in the up-down direction Z, and may be bent or curved into a crank shape midway. Similarly, the upper horizontal strut 13 and the lower horizontal strut 14 do not necessarily extend linearly in the front-rear direction Y, and may be bent or curved in the crank shape midway. In the present embodiment, each of the pair of left and right upper struts 13 includes a front portion 13A extending from the upper end of the vertical column 12 in the front side Y1 to the rear side Y2, a middle portion 13B extending from the rear end of the front portion 13A to the upper side Z1, and a rear portion 13C extending from the upper end of the middle portion 13B to the rear side and connected to the upper end of the vertical column 12 of the rear side Y2, and as a whole is configured in a shape of a crank.

The decorative cover 11 is formed in a shape of a plate, and covers the outer frame 10 at least from the left side X1, the right side X2, the front side Y1, the back side Y2 and the upper side Z1. A portion of the decorative cover 11 that covers the outer frame 10 from the upper side Z1 is provided thereon with an entrance (not shown) for taking the laundry into the washing machine and taking the laundry out of the washing machine 100.

The outer tub 3 is, for example, made of resin, and has a bottomed cylindrical shape. The outer tub 3 is disposed inside the outer frame 10, and water can be stored inside the outer tub 3. The outer tub 3 has a substantially cylindrical circumferential wall 15 arranged in the up-down direction Z and a disc-shaped bottom wall 16 that closes a hollow portion of the circumferential wall 15 from the lower side Z2. The circumferential wall 15 is provided therein with an opening 15A surrounded by an upper end edge of the circumferential wall. The opening 15A is located just below the above-described entrance (not shown) of the decorative cover 11 so that the hollow portion of the circumferential wall 15 communicates with the entrance.

A plurality of ribs 17 is formed on the outer peripheral surface of the circumferential wall 15 to protrude toward the radial outer side R of the circumferential wall 15 for reinforcing the circumferential wall 15. The ribs 17 include a longitudinal rib 17A that extends in the up-down direction and a horizontal rib 17B that extends in the peripheral direction S of the outer tub 3. Receiving portions 18 are provided at the lower ends of two longitudinal ribs 17A adjacent in the circumferential direction S. Four receiving portions 18 are integrally provided at the lower end portion of the outer peripheral surface of the circumferential wall 15 in a manner of being arranged one by one at four corners of the machine housing 1 in a plan view. The two receiving portions 18 located at the front side Y1 are referred to as front receiving portions 18A, and the remaining two receiving portions 18 located at the rear side Y2 are referred to as rear receiving portions 18B. The two front receiving portions 18A are arranged closer to the lower side Z2 than the front portion 13A of the upper horizontal strut 13 and are spaced apart in the left-right direction. The two rear receiving portions 18B are arranged closer to the lower side Z2 than the rear portion 13C of the upper horizontal strut 13 and are spaced apart in the left-right direction.

Each receiving portion 18 integrally includes a plate-shaped base portion 19 that is bridged between two adjacent longitudinal ribs 17A and is curved in a manner of bulging to the outer side R radially, and a dome-shaped engagement portion 20 that bulges from an upper end of the base portion 19A toward the upper side Z1. The space enclosed by the lower ends of two adjacent longitudinal ribs 17A, the receiving portion 18 provided over these longitudinal ribs 17A, the engagement portion 20 at the upper end of the receiving portion 18 and the outer peripheral surface of the circumferential wall 15 is called an accommodation space 21. The accommodation space 21 is a recess that is recessed toward the upper side Z1 and faces the engagement portion 20 and is exposed from the lower end of the base portion 19 toward the lower side Z2. The receiving portion 18 is formed with a through hole 18C that penetrates the upper end of the engagement portion 20 in the up-down direction Z and a slit 18D that extends continuously from the through hole 18C to the lower side Z2 and bisects the entire receiving portion 18 in the circumferential direction S. The through hole 18C and the slit 18D are in a state of communicating with the accommodation space 21.

The lower surface of the bottom wall 16 is provided with a plurality of ribs 22 protruding toward the lower side Z2 and reinforcing the bottom wall 16, a drain 23 for discharging the water stored in the outer tub 3 and the like.

The inner tub 4 shown by the two-dot chain line in FIG. 1 is made of, for example, metal, and is formed in a bottomed cylindrical shape smaller than the outer tub 3 by a loop, and is housed coaxially in the outer tub 3. The inner tub 4 can house the laundry inward. An opening 4A that communicates with the opening 15A of the outer tub 3 from immediately below is formed on the upper surface of the inner tub 4. A user of the washing machine 100 puts the laundry into the washing machine and takes them out of the washing machine via the above-described entrance (not shown) of the decorative cover 11, the opening 15A and the opening 4A. A plurality of through holes (not shown) is formed in the inner tub 4 so that the water in the outer tub 3 can travel between the outer tub 3 and the inner tub 4 via the through holes. Therefore, the water level in the outer tub 3 is the same as the water level in the tub 4. At a portion of the bottom wall of the inner tub 4 that coincides with the center of the inner tub 4, a rotation shaft 4B protruding toward the lower side Z2 is disposed. The rotation shaft 4B is rotatably supported by the bottom wall 16 of the outer tub 3. Therefore, the inner tub 4 is rotatable around the rotation shaft 4B.

The motor 5 is an electric motor such as a frequency inverter motor. The motor 5 is fixed to the bottom wall 16 of the outer tub 3 from the lower side Z2. The motor 5 has an output shaft (not shown) that protrudes toward the upper side Z1. The transmission mechanism 6 is interposed between the output shaft of the motor 5 and the rotation shaft 4B of the inner tub 4. As the transmission mechanism 6, a known one may be used. The transmission mechanism 6 transmits the driving force outputted by the motor 5 from the output shaft to the rotation shaft 4B. As a result, the inner tub 4 rotates. In particular, in the dewatering process, the inner tub 4 is rotated at a high speed in order to cause centrifugal force to act on the laundry to effectively dewater the laundry. It should be noted that a pulsator (not shown) that rotates to stir the stored laundry is provided in the inner tub 4, and the driving force of the motor 5 is transmitted from the transmission mechanism 6 to the pulsator.

The supporting member 7 is a member formed in a rod shape, which is also referred to as a hanging rod, and is disposed in the machine housing 1 in in a state of being elongated vertically. There are four supporting members 7, which are provided at the four corners of the machine housing 1 one by one. Of the four supporting members 7, the pair of left and right supporting members 7 at the front side Y1 is referred to as front supporting members 7A, and another pair of left and right supporting members 7 at the rear side Y2 is referred to as rear supporting members 7B. FIG. 1 and FIGS. 3 and 6 to be mentioned later show the front supporting member 7A and the rear supporting member 7B located at the left side X1 one by one, and the front supporting member 7A and the rear supporting member 7B located at the right side X2 are not illustrated. However, the pair of right and left front supporting members 7A overlaps each other when viewed in the left-right direction X, and the pair of left and right rear supporting members 7B overlaps each other when viewed from the left-right direction X.

A friction damper can be used as an example of the supporting member 7. Of course, other well-known dampers, such as the hydraulic damper, can be used as the supporting member 7. When the supporting member 7 is a friction damper, the supporting member 7 includes a rod 28 that extends upward and downward in an elongated and linear shape and a hollow housing 29 that houses the lower end of the rod 28. Referring to FIG. 2, which is a schematic longitudinal sectional view of the main portion and the peripheral portion of the supporting member 7, the supporting member 7 includes a disk-shaped damper member 30 connected to the lower end of the rod 28 in the housing 29 and an urging member 31 such as a coil spring, provided in the body 29. The rod 28 is movable relative to the housing 29, and by this relative movement, the entire supporting member 7 can expand and contract. In addition, since the urging member 31 urges the damper member 30 toward the lower side Z2 within the housing 29, the supporting member 7, as a whole, is elastically extensible.

Referring to FIG. 3, which is a schematic left view of the main portion of the washing machine 100, in conjunction with the rod 28, a pair of left and right upper horizontal struts 13 of the outer frame 10 is provided with one connection portion 32 at the front portion 13A and one connection portion 32 at the rear portion 13C (see FIG. 1). In other words, there are four connection portions 32 in total. Each of the connection portions 32 is formed in a thin metallic plate shape in the up-down direction Z. The connection portion 32 may be provided integrally with the upper horizontal strut 13 or may be fixed to the upper horizontal strut 13 with screws or the like as a separate member. The connection portion 32 provided on the upper horizontal strut 13 at the left side X1 is configured in a manner of protruding to the right side X2 toward the washing tub 2 from this upper horizontal strut 13. The connection portion 32 (not shown) provided on the upper horizontal strut 13 at the right side X2 is configured in a manner of protruding to the left side X1 toward the washing tub 2 from this upper horizontal strut 13. In each of the upper horizontal strut 13, the connection portion 32 provided at the front portion 13A is referred to as a front side connection portion 32A, and the connection portion 32 provided at the rear portion 13C is referred to as a rear side connection portion 32B (see FIG. 1). Each of the connection portions 32 is formed with a through hole 32C that runs through the connection portion 32 in the up-down direction Z. An inner peripheral surface 32D defining the through hole 32C in the connection portion 32 is formed into a spherical shape that becomes narrower toward the lower side Z2.

At the upper end of the rod 28, a hemispherical upper engagement portion 28A bulging toward the lower side Z2 is provided. The upper engagement portion 28A of each of the front supporting members 7A is fitted from the upper side Z1 into the through hole 32C of the front side connection portion 32A located at the same position in the left-right direction X so as to be in a state of engaging with the front side connection portion 32A from the upper side Z1. The upper engagement portion 28A of each of the rear supporting members 7B is fitted from the upper side Z1 into the through hole 32C of the rear side connection portion 32B located at the same position in the left-right direction X so as to be in a state of engaging with the rear side connection portion 32A from the upper side Z1. Each of the upper engagement portions 28A is in a state of being in spherical contact with the inner peripheral surface 32D that defines the through hole 32C in the connection portion 32.

The housing 29 is formed in a substantially cylindrical shape whose long edge is in the longitudinal direction of the rod 28. The upper end portion of the housing 29, as the lower engagement portion 29A, is formed as a hemispherical shape bulging toward the upper side Z1. The rod 28 is in a state of vertically penetrating the upper end 29B of the lower engagement portion 29A and protruding toward the upper side Z1. The lower engagement portion 29A of each of the front supporting members 7A is fitted from the lower side Z2 into the accommodation space 21 of the front receiving portion 18A at the same position in the left-right direction X so as to be in a state of engaging with the engagement portion 20 of the front receiving portion 18A from the lower side Z2. The lower engagement portion 29A of each of the rear supporting members 7B is fitted from the lower side Z2 into the accommodation space 21 of the rear receiving portion 18B located at the same position in the left-right direction X so as to be in a state of engaging with the engagement portion 20 of the rear receiving portion 18B from the lower side Z2. In this way, the four receiving portions 18 are mounted one by one to the lower engagement portions 29A located at the lower portion of each of the supporting members 7. It should be noted that when the lower engagement portion 29A is fitted into the accommodation space 21, the rod 28 passes through the slit 18D of the receiving portion 18.

At each of the supporting members 7, the lower engagement portion 29A is in spherical contact with the inner peripheral surface 20A (see FIG. 2) where the accommodation space 21 is defined in the engagement portion 20, and the rod 28 is in the state of protruding to the upper side Z1 from the through hole 18C of the upper end of the receiving portion 18. The rod 28 may be disposed to extend vertically in the up-down direction Z or may be disposed to be inclined towards the left-right direction X and the front-back direction Y with respect to the up-down direction Z. In the present embodiment, the rod 28 of the front supporting member 7A is obliquely arranged in such a way that as the rod 28 goes to the upper side Z1, the rod 28 is inclined more towards the front side Y1, and the rod 28 of the rear supporting member 7B is obliquely arranged in such a way that as the rod 28 goes to the upper side Z1, the rod 28 is inclined more towards the rear side Y2.

Each of the supporting members 7 is in a state of being suspended from the connection portion 32 of the upper horizontal strut 13 of the outer frame 10 (see FIG. 1). The lower engagement portion 29A of the housing 29 located at the lower end portion of the supporting member 7 is connected to the outer tub 3 of the washing tub 2 by the receiving portion 18. Since each supporting member 7 is elastically extensible and contractible, the four supporting members 7 are in a state of elastically supporting the washing tub 2, the motor 5 secured to the outer tub 3 and the transmission mechanism 6 (see also FIG. 1). Therefore, the vibration of the washing tub 2 generated along with the rotation of the inner tub 4 during the washing operation is prevented from being transmitted to the machine housing 1 through the connection portion 32.

In addition, for each of the supporting members 7, since the damper member 30 moves together with the lower end portion of the rod 28 when the supporting member 7 expands and contracts, and rubs the inner peripheral surface 29C (see FIG. 2) of the housing 29, a frictional force is generated between the damper member 30 and the inner peripheral surface 29C of the housing 29. With this frictional force, the vibration generated by the washing tub 2 is reduced. As described above, each of the supporting members 7 is in a state where the upper engagement portion 28A is in spherical contact with the connection portion 32 and the lower engagement portion 29A is in spherical contact with the engagement portion 20 of the receiving portion 18. Therefore, the inclination of the supporting member 7 with respect to the up-down direction Z is freely changed in such a way that the force caused by the vibration of the washing tub 2 does not act on the supporting member 7 and the machine housing 1.

The four receiving portions 18 are arranged at the same height. In particular, the through holes 18C of the four receiving portions 18 are located at the same position in the up-down direction Z, respectively. Therefore, the housings 29 of the four supporting members 7, which are fitted into the accommodation space 21 of the receiving portion 18 from the lower side Z2, are arranged at the same position in the vertical direction Z. Specifically, the upper ends 29B of the lower engagement portions 29A of the housings 29 of the four supporting members 7 that are exposed from the through holes 18C are arranged at the same position in the up-down direction Z.

On the other hand, among the four connection portions 32 where the upper horizontal struts 13 of the machine housing 1 are engaged with the upper side engagement portions 28A of the engagement supporting members 7, the front connection portion 32A provided at the front portion 13A is located at a position that is lower than the rear connection portion 32B. This rear connection portion 32B is provided at the rear portion 13C (refer to FIG. 1) located at a position higher than that of the front portion 13A. In this case, among the four supporting members 7, a pair of front supporting members 7A having the upper engagement portions 28 that are engaged with the front connection portions 32A has the same length, and the other pair of rear supporting members 7B having the upper engagement portions 28A that are engaged with the rear connection portions 32B has the same length. However, the length of the pair of front supporting members 7A and the length of the pair of rear supporting members 7B are different. Strictly speaking, the front supporting member 7A is shorter than the rear supporting member 7B. It should be noted that, in one example, the length of the supporting member 7 refers to a length of the line segment L that connects the portion 28B of the upper engagement portion 28A that coincides with the lower surface of the connection portion 32 to the upper end 29B of the lower engagement portion 29A and extends along the rod 28 when the operation of the machine housing 100 is stopped. The length of the line segment L is also the portion of a range of each of the supporting members 7 from the receiving portion 18 to the connection portion 32. In other words, the length of the line segment L refers to a length of a portion of the supporting member 7 positively contributing to reduce vibrations. Of course, as another example, the total length of the rod 28 and the total length of the supporting member 7 may be defined as the length of the supporting member 7.

FIG. 4 is a diagram showing a relationship between an amplitude of the vibration of the outer tub 3 of the washing tub 2 generated along with the rotation of the inner tub 4 during the dewatering process and a length difference between a front supporting member 7A and a rear supporting member 7B. FIG. 5 is a diagram showing a relationship between an amplitude of the vibration of the outer tub 3 generated along with the termination of the rotation of the inner tub 4 at the end of the dewatering process and a length difference between the front supporting member 7A and the rear supporting member 7B. In FIGS. 4 and 5, the horizontal axis represents the length difference between the front supporting member 7A and the rear supporting member 7B when the front supporting member 7A is shorter than the rear supporting member 7B. On the other hand, the longitudinal axis of FIG. 4 represents the amplitude of the vibration of the outer tub 3 generated during the rotation of the inner tub 4 in the dehydration, and the longitudinal axis of FIG. 5 represents the amplitude of the vibration of the outer tub 3 generated at the termination of rotation of the inner tub 4 when a braking is applied along with the termination of the dewatering process. The unit of the length difference and the amplitude is, for example, mm.

The braking to the rotation of the inner tub 4 can be realized in a manner in which a control portion (not shown) provided in the washing machine 100 controls a duty ratio to cause a rapid stop of the rotation of the motor 5 or in a manner in which a braking device (not shown) is additionally provided and the control portion is used to cause the braking device to operate such that the rotation of the motor 5 is stopped rapidly.

When a structure in which the four receiving portions 18 receiving the lower end portions of the supporting members 7 are arranged at the same height is used, as shown in FIG. 4, even if the length difference between the front supporting member 7A and the rear supporting member 7B becomes larger, the amplitude of the vibration of the outer tub 3 during the rotation of the inner tub 4 in the dewatering process is almost unchanged. On the other hand, as shown in FIG. 5, when the length difference between the front supporting member 7A and the rear supporting member 7B becomes larger, the amplitude of the vibration of the outer tub 3 generated when the rotation of the inner tub 4 is stopped due to the braking becomes smaller. In other words, it is considered that the vibration of the outer tub 3 due to the stop of the rotation of the inner tub 4 is effectively reduced because of the difference in length between the front supporting member 7A and the rear supporting member 7B.

Therefore, when a structure in which the length of the pair of front supporting members 7A and the length of the pair of rear supporting members 7B are different and the four receiving portions 18 are arranged in the same height position is adopted, even if a braking is applied to the rotation of the inner tub 4 for stopping the dewatering process when the inner tub 4 is rotating during the dewatering process, the vibration of the outer tub 3 can be effectively suppressed by the four supporting members 7. This can prevent the outer tub 3 of the washing tub 2 inside the machine housing 1 from vibrating and colliding with the machine housing 1.

FIG. 6 is a left view of a washing machine in a modified example. In FIG. 6, the same parts as those already described in FIGS. 1 to 3 are denoted by the same reference numerals, and description of these parts will be omitted. In the washing machine 100 already described with reference to FIGS. 1 to 3, the washing tub 2 is always arranged vertically. However, the washing machine 100 according to the modified example shown in FIG. 6 can change the posture of the washing tub 2.

Specifically, the washing machine 100 according to the modified example further includes a supporting frame 50, a rotation portion 51, a lock release mechanism 52 and a driving mechanism 53.

The supporting frame 50 includes a pair of left and right side plates 54 and a bridge member (not shown) that is bridged between the pair of side plates 54. In FIG. 6, only the side plate 54 at the left side X1 is illustrated. Each of the side plates 54 is formed into a substantially rectangular shape when viewed in the left-right direction X, and it thin in the left-right direction X. A washing tub 2 is disposed between the pair of side plates 54.

A position of the right side and a position of the left side of the outer tub 3 of the washing tub 2, which are at the same position when viewed from the left-right direction X, each is provided with a metallic rotation shaft 55 protruding outward in the left-right direction X. The rotation shaft 55 of the outer tub 3 protruding towards the left side X1 penetrates the side plate 54 at the left side X1, and is rotatably supported by the side plate 54 at the left side X1 via a bearing (not shown). The rotation shaft 55 of the outer tub 3 (not shown) protruding towards the right side X2 penetrates the side plate 54 of the right side X2, and is rotatably supported by the side plate 54 of the right side X2 via a bearing (not shown). Accordingly, the washing tub 2 having the outer tub 3 and the inner tub 4 (not shown) is supported by the supporting frame 50 and is rotatable around the rotation shaft 55 in a manner of crossing with the up-down direction Z. Specifically, with the rotation of the washing tub 2, a central axis J of the outer tub 3 and the inner tub 4 is inclined towards the front-back direction Y with respect to the up-down direction Z. The rotation direction of the washing tub 2 is referred to as the direction of rotation K.

An intersection angle of an imaginary reference axis M extending in the up-down direction Z and the central axis J which is an acute angle is a rotation angle θ of the washing tub 2 with respect to the reference axis M. The smaller the rotation angle θ is, the closer the washing tub 2 is to the upright posture. The larger the rotation angle θ is, the more the washing tub 2 is inclined towards the front side Y1 in such a way that the opening 15A of the outer tub 3 faces the front side Y1. The rotation angle θ can be changed be changed in five stages of, for example, 5 degrees, 15 degrees, 30 degrees, 45 degrees and 60 degrees. The rotation angle θ in FIG. 6 is 60 degrees. In FIG. 6, the moving track of the end surface on the opening 15A side of the outer tub 3 when the washing tub 2 is rotated between 5 degrees and 60 degrees is illustrated by a two-dot chain line.

As an example of the application of the washing machine 100 in the modified example, when the laundry are thrown into the washing tub 2 at the start of the washing operation, the rotation angle θ is set to be 45 degrees so that the laundry can be easily introduced. It is noted that, in the machine housing 1 of the washing machine 100 according to the modified example, a connection surface 1C that connects the front surface 1A and the upper surface 1B and descends towards the front side Y1 is provided, and the above-described entrance (not shown) is formed across the front surface 1A and the connection surface 1C. In addition, after the laundry is put in, when detecting the load amount of the laundry or supplying water to the outer tub 3, the rotation angle θ is set to be 5 degrees. Then, during the washing process and the rinsing process, the rotation angle θ is set to be varied between 5 degrees and 60 degrees in order to facilitate the alternation of the positions of the laundry in the inner tub 4 for effective washing and rinsing.

An opening 54A that penetrates the side plate 54 in the left-right direction X is formed in a region of the side plate 54 of the left side X1 closer to the lower side Z2 than the rotation shaft 55 is. The opening 54A is formed in a substantially rectangular shape elongated in the front-rear direction Y.

The rotation portion 51 is a metal plate which is thin in the left-right direction X and is formed in a substantially fan-like shape bulging to the front side Y1 as viewed from the left-right direction X. The rotation portion 51 has an outer peripheral edge 51A formed in an arc shape along the rotation direction K and bulging toward the front side Y1. A through hole 51B that penetrates the rotation portion 51 in the left-right direction X is formed at a position of the rotation portion 51 in accordance with the center of curvature of the outer peripheral edge 51A. A plurality of recesses 51C are formed on the outer peripheral edge 51A. There are five recesses in this embodiment. These recesses 51C are recessed toward the through-hole 51B and penetrate the rotation portion 51 in the left-right direction X, and are arranged side by side in the rotation direction K. The intervals between the adjacent recesses 51C may be constant or may be different depending on the position of the rotation portion 51. In the present embodiment, corresponding to the rotation angle θ which is set to 5 degrees, 15 degrees, 30 degrees, 45 degrees, and 60 degrees, in the rotation portion 51 in the attitude of FIG. 1, the two recesses 51C at the most rear side Y2 and the adjacent position thereof are spaced apart by 10 degrees in the rotation direction K (the circumferential direction with the through hole 51B as the center), and the intervals between the other adjacent recesses 51C are set to be 15 degrees uniformly.

The rotation portion 51 is disposed to be closer to the left side X1 than the side plate 54 is. The rotation shaft 55 protruding to the left side X1 at the outer tub 3 and running through the side plate 54 at the left side X1 is inserted into the through hole 51B of the rotation portion 51, and is fixed to the rotation portion 51. Thus, the rotation portion 51 is connected to the outer tub 3 the rotation shaft 55, such that the rotation portion 51 may rotate integrally with the outer tub 3.

The rotation portion 51 in the attitude of FIG. 6 is integrally provided towards the lower side Z2, at the rear end of the outer peripheral edge 51A, specifically, with an extension portion 51D protruding outward in the radial direction T of the rotation portion 51 with the through hole 51B as the center. The extension portion 51D is formed with a guide hole 51E that is long in the radial direction T and runs through the extension portion 51D in the left-right direction X. The guide hole 51E and the opening 54A of the side plate 54 at the left side X1 are located at the same position in the up-down direction Z, and always faces the opening 54A from the left side X1.

The lock release mechanism 52 is fixed to the left surface of the side plate 54 at the left side X1. The lock release mechanism 52 includes a main body portion 56 provided with an actuator (not shown) composed of a solenoid or the like, and a lock portion 57 formed in a convex shape protruding toward the back side Y2. The lock portion 57 is supported by the main body portion 56 in a way that the lock portion 57 is slideable in the front-back direction Y. The actuation of the actuator of the main body 56 causes the lock portion 57 to slide between an entry position where the lock portion 57 enters toward the rearmost side Y2 and a retracting position where the lock portion 57 is retracted toward the foremost side Y1. The lock portion 57 in FIG. 6 is located at the entry position in a state of being embedded in the recess 51C provided at the same position in the rotation direction K. Thus, the rotations of the rotation portion 51 and the washing tub 2 are locked. In this state, when the lock portion 57 is retreated to the retracting position, the lock portion 57 is disengaged from the recess 51C, and thus, the locking of the rotation portion 51 and the washing tub 2 is released.

The driving mechanism 53 includes a frame 58, a pair of receiving portions 59, a threaded shaft 60, a motor 61, a coupling 62, a nut member 63 and a sensor 64.

The frame 58 is formed by bending a metal plate into, for example, a crank shape, and the frame 58 is fixed to the side plate 54 from the right side X2 so as to cover the opening 54A of the side plate 54 at the left side X1 from the right side X2. The pair of receiving portions 59 is fixed to the frame 58 in a state of being spaced apart from each other in the front-back direction Y and protruding from the frame 58 to the left side X1. The threaded shaft 60 is formed in a columnar shape elongated in the front-rear direction Y, and is provided with a helical thread 60A extending in a spiral shape formed over substantially the entire outer peripheral surface thereof. The threaded shaft 60 is rotatably supported at two ends by bearing (not shown) provided on the pair of front and rear receiving portions 59.

The motor 61 is a general electric motor, and has an output shaft 65 that protrudes to the rear side Y2 and is arranged coaxially with the threaded shaft 60. The front end of the threaded shaft 60 and the output shaft 65 are coupled to each other by a coupling 62 such that the threaded shaft 60 and the output shaft 65 can be integrally rotated. Therefore, when the motor 61 is driven so that the output shaft 65 is rotated, the threaded shaft 60 rotates integrally with the output shaft 65. The nut member 63 has an annular nut formed with thread (not shown) extending in a spiral shape at an inner peripheral surface thereof and is externally fitted to the threaded shaft 60 in a such a way that the thread is threadedly connected to the thread 60A of the threaded shaft 60. When the threaded shaft 60 is rotated by the driving of the motor 61, the nut member 63, as a whole, moves in the axial direction of the threaded shaft 60, i.e. the front-back direction Y, along with the rotation of the screw shaft 60. The nut member 63 is secured with a connection pin 66 which is inserted into the extension portion 51D of the rotation portion 51, such that the nut member 63 is connected to the rotation portion 51 via the connection pin 66. Therefore, when the nut member 63 moves in the front-rear direction Y along with the rotation of the threaded shaft 60, the rotation portion 51 is pulled by the nut member 63 in the front-rear direction Y, thereby rotating with the washing tub 2.

The sensor 64 is a sensor that detects the rotation angle θ of the washing tub 2 based on the position of the nut member 63 in the front-rear direction Y. As the sensor 64, an optical sensor such as a photo sensor may be used. In this case, the number of the sensors 64 is set to be the same as the number of the recesses 51C of the rotation portion 51, and the sensors 54 are fixed to the frame 58 in a state of being aligned in the front-rear direction Y. Each sensor 64 is formed with a groove 64A penetrating the sensor 64 in the front-rear direction Y, and the sensor 64 is in a state that the detection light traverses the groove 64A in the up-down direction Z. The nut member 63 is provided with a rod-shaped detected portion 63A, which is referred to as a limiting portion. When the rotation angle θ is set to be one of 5 degrees, 15 degrees, 30 degrees, 45 degrees and 60 degrees, the detected portion 63A is embedded in the groove 64A of one of the sensors 64 and shields the detection light of the groove 64A. Therefore, the five sensors 64 collectively detect which one of 5 degrees, 15 degrees, 30 degrees, 45 degrees and 60 degrees is the rotation angle θ.

In the washing machine 100 of the modified example, a pair of left and right longitudinal plates 71 protruding outward in the front-rear direction Y is provided on a front end edge and a rear end edge of each side plate 54 of the supporting frame 50. One receiving portion 18 is provided on the pair of longitudinal plates 71, and the receiving portion 18 is integrated with the longitudinal plates 71. Like the case in the above-described embodiment (see FIGS. 1 to 3), there are four receiving portions 18, which are arranged at the four corners of the machine housing 1 one by one when viewed from top. Among the four receiving portions 18, the two front receiving portions 18A are disposed closer to the lower side Z2 than the front portion 13A of the upper horizontal strut 13, and are spaced apart from each other in the left-right direction, and the two rear receiving portions 18B are disposed closer to the lower side Z2 than the rear portion 13C of the upper horizontal strut 13, and are spaced apart from each other in the left-right direction.

The base portion 19 of the front receiving portion 18A is formed into a curved plate shape in a manner of being bridged between two longitudinal plates 71 which are provided at the front edges of the side plates 54 and bulging toward the front side Y1. The base portion 19 of the rear receiving portion 18B is formed into a curved plate shape in a manner of being bridged between two longitudinal plates 71 which are provided at the rear edges of the side plates 54 and bulging toward the rear side Y2. The accommodation space 21 is a space enclosed by the two adjacent longitudinal plates 71, the base portions 19 and the engagement portion 20.

In the washing machine 100 in the modified example, four supporting members 7 are arranged at four corners of the machine housing 1 one by one. In the washing machine 100 according to the modified example, as shown in FIG. 3, among the four supporting members 7A, the upper engagement portions 28A of the two front supporting members 7A are in a state of being engaged from the upper side A1 with the front connection portions 32A that are provided at the same position in the left-right direction X, and the upper engagement portions 28A of the two rear supporting members 7B are in a state of being engaged from the upper side Z1 with the rear side connection portions 32B that are provided at the same position in the left-right direction X. The lower engagement portion 29A of each of the front supporting members 7A is fitted from the lower side Z2 into the accommodation space 21 of the front receiving portion 18A located at the same position in the left-right direction X so as to be engaged with the engagement portion 20 of the front connection portion 32A from the lower side Z2. The lower engagement portion 29A of each of the rear supporting members 7B is fitted from the lower side Z2 into the accommodation space 21 of the rear receiving portion 18B located at the same position in the left and right direction X so as to be engaged with the engagement portion 20 of the rear connection portion 32B from the lower side Z2. The lower engagement portion 29A is in a state of being spherical contact with the inner peripheral surface 20A (see FIG. 2) that defines the accommodation space 21 in the engagement portion 20, and the rod 28 is in a state of protruding from the through hole 18C of the upper end of the receiving portion 18 to the upper side Z1.

Each of the supporting members 7 is in a state of being suspended from the connection portion 32 provided on the upper horizontal strut 13 of the outer frame 10. The four receiving portions 18 are mounted one by one to the lower engagement portions 29A located at a lower portion of the supporting members 7. Thus, as shown in FIG. 6, each of the supporting members 7 is connected to the outer tub 3 of the washing tub 2 via the side plate 54 of the supporting frame 50 through the receiving portion 18. Since each supporting member 7 is elastically extensible and retractable, the four supporting members 7 suspend the washing tub 2, the motor 5 and the transmission mechanism 6 (see FIG. 1) which are fixed to the outer tub 3, the supporting frame 50, the rotation portion 51 and the lock release mechanism 52 for elastic support.

Similar to the washing machine 100 of the modified example in which the washing tub 2 is rotatable as described above, all the receiving portions 18 for receiving the lower ends of the supporting members 7 are arranged at the same height position, and the length of the pair of front supporting members 7A is different from the length of the pair of rear supporting members 7B. Strictly speaking, the front supporting member 7A is shorter than the rear supporting member 7B (see FIG. 3). In this case, as described with reference to FIGS. 4 and 5, since the vibration of the outer tub 3 is effectively suppressed by the four supporting members 7, the vibration of the outer tub 3, that is, the vibration of the washing tub 2, and the collision with the machine housing 1 can be prevented.

The present disclosure is not limited to the above-described embodiments, and various changes may be made within the scope of the claims.

For example, among the four supporting members 7, the pair of front supporting side members 7A is shorter than the pair of rear supporting members 7B. However, the pair of rear supporting members 7B may be shorter than the pair of front supporting members 7A. In addition, the four supporting members 7 may be configured such that instead of the pair of supporting members 7 on the front side Y1 and the pair of supporting members 7 on the rear side Y2 being different in length, the pair of supporting members 7 on the left side X1 and the pair of supporting members 7 on the right side X2 are different in length.

Claims

1. A washing machine, comprising: a machine housing,a washing tub having an inner tub which accommodates laundry and is rotatable and an outer tub for receiving the inner tub, and being provided inside the machine housing,four supporting members, which are configured to be in a shape of a rod suspended from the machine housing and elastically support the washing tub, andreceiving portions, which are mounted at the lower portion of each of the supporting members respectively to connect the supporting members to the washing tub,wherein all the receiving portions are provided at the same height, and among the four supporting members, a length of a pair of supporting members and that of another pair of supporting members are different.

2. The washing machine according to claim 1, wherein the washing tub is capable of rotating in a manner of crossing with a vertical direction.