Hydraulic Bushing For A Top Load Washing Machine

Description

FIELD

The present disclosure relates generally to laundry appliances and more particularly to a hydraulic bushing that limits travel of a wash unit tub/hung mass inside a cabinet of a top load/vertical axis washing machine.

BACKGROUND

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

Laundry appliances (i.e., laundry and/or washing machines) are prolific in both residential and commercial settings, where they are used to clean laundry, such as clothes, towels, and bedding.

Many laundry appliances, such as laundry and/or washing machines, have a top-load configuration, where the washing machine includes an appliance housing with a top appliance opening that is accessed by a top-mounted appliance door. Such laundry appliances typically have a wash unit tub that is hung within the appliance housing by multiple suspension rods, which allow the wash unit tub to move and oscillate to some degree inside the appliance housing. As a result, the wash unit tub is sometimes referred to as the “hung mass” of the laundry appliance. A drum is positioned inside the wash unit tub and is rotatable with respect to both wash unit tub and the appliance housing about a vertical axis of rotation. As a result, laundry appliances of this configuration are sometimes referred to as vertical axis washing machines.

A motor housed within the appliance housing rotates the drum. The drum typically has an upper drum end with a drum opening that provides access to a laundry compartment inside the drum and a lower drum end that is coupled to the motor. During wash cycles, a mixture of wash water and detergent is introduced into the laundry compartment as the drum rotates to clean the laundry located inside the laundry compartment. The degree to which the wash unit tub oscillates inside the appliance housing can increase when a heavy and/or uneven load of laundry is placed inside the laundry compartment. This degree of oscillation of the wash unit tub often transmits unwanted travel and/or vibration and/or noise from the wash unit tub to the appliance housing and thereby, generally, to the laundry appliance. As a result, solutions for eliminating or decreasing the unwanted travel, vibration, and/or noise during operation of laundry appliance is desirable.

SUMMARY

This section provides a general summary of at least one enabling embodiment of the present disclosure and is not comprehensive of all aspects or configurations of the present disclosures that are within the full scope or all its features.

In accordance with one aspect of the present disclosure, a suspension mount assembly for a laundry appliance is provided. The laundry appliance generally includes an appliance housing, a wash unit tub disposed inside the appliance housing, and a drum that is rotatably supported within the wash unit tub. In one aspect of the disclosure, the laundry appliance has a top-load configuration. Thus, the appliance housing includes an upper frame supporting an upper housing wall, a laundry compartment opening in the upper housing wall, and an appliance door that is pivotally mounted to the upper frame and/or upper housing wall to open and close the laundry compartment opening. The wash unit tub includes an upper tub end, a lower tub end, and a tub sidewall that extends between the upper and lower tub ends. The wash unit tub also includes a tub opening at the upper tub end, where the tub opening is aligned with the laundry compartment opening in the upper housing wall. The drum is rotatably supported within the wash unit tub for rotation about a substantially vertical axis. As such, the laundry appliance may generally be characterized as a vertical axis washing machine. It should therefore be appreciated that the drum includes a laundry compartment that is accessible through the laundry compartment opening in the upper housing wall.

The laundry appliance includes a plurality of suspension rod assemblies that extend between the upper frame of the appliance housing and the wash unit tub. The wash unit tub is hung from and supported by these suspension rod assemblies. Each suspension rod assembly includes a suspension rod that extends from an upper rod end to a lower rod end. A plurality of upper suspension mount assemblies pivotally couple upper rod ends of the suspension rods to the upper frame of the appliance housing. Each upper suspension mount assembly includes a socket that is disposed in the upper frame of the appliance housing, and a bushing. The upper rod end extends through the bushing and all or part of the bushing is received in the socket in the upper frame of the appliance housing. As a result, the bushing is positioned between the socket and the upper washer.

The bushing is made of a resilient material. As such, the bushing permits relative movement between the upper rod end and the socket in the upper frame of the appliance housing. The bushing is configured to reduce and dampen vibrations transmitted between the upper rod end and the upper frame of the appliance housing. It should be appreciated that rotation of the drum during operation of the laundry appliance (e.g., during wash and/or spin cycles) can cause the wash unit tub to vibrate or oscillate. These vibrations and/or oscillations can be particularly noticeable or severe when there is a heavy and/or unbalanced load of laundry inside the laundry compartment. Advantageously, the bushings of the present disclosure reduce and/or dampen the vibrations and oscillations that the suspension rods transmit from the wash unit tub to the appliance housing to reduce the amount of noise and vibration that is perceivable from outside the laundry appliance.

The bushing of the present disclosure has a hydraulic passageway that allows and facilitates fluid flow between two chambers disposed inside the bushing. The hydraulic passageway is open to a pumping chamber at a first hydraulic opening and is open to a compensation chamber at a second hydraulic opening. The hydraulic passageway operates as a fluid mass channel that is configured to allow a mass of fluid to travel from the pumping chamber to the compensation chamber. The hydraulic passageway may extend between the first hydraulic opening and the second hydraulic opening. The hydraulic passageway may have a diameter. The hydraulic passageway may extend helically, about a first axis, from the first hydraulic opening to the second hydraulic opening. The hydraulic passageway may extend through a chamber dividing wall that is positioned between the pumping and compensation chambers. In addition, the hydraulic passageway may form a partial helix with an arc length that is more than 90 degrees and less than 360 degrees. The hydraulic passageway has a diameter and a length that may be configured to define a particular channel resonance frequency, which can be tuned for a specific laundry appliance to eliminate noise and vibration at specific frequencies. The hydraulic passageway has a diameter, a length, or an arc length, or a pitch that may be configured to define a channel resonance frequency.

During operation of the laundry appliance (e.g., during wash and/or spin cycles) the wash unit tub vibrates and oscillates. These vibrations and/or oscillations can be particularly noticeable or severe at a resonant frequency of the wash unit tub when there is a heavy and/or unbalanced load of laundry inside the laundry compartment. The resilience of the bushings reduce and dampens the vibrations transmitted between wash unit tub and the laundry appliance. Specifically, the undesirable vibration and/or oscillation of wash unit tub causes the one or more suspension rods to move in a vertical direction relative to the appliance housing, thereby transmitting compression forces to upper rod ends.

The vibrations and/or oscillations of wash unit tub transmits a frequency of forces to the bushings. When the forces applied to bushings are at or above a resonance frequency, the bushings become stiffer. At or above the resonance frequency, fluid flows through the hydraulic passageway from the pumping chamber to the compensation chamber, causing the stiffness of the bushing to increase. When forces are applied below the resonance frequency, the stiffness of the bushing remains relatively constant. Below the resonance frequency, fluid flow through the hydraulic passageway is delayed due to the helical configuration of the hydraulic passageway about the first axis.

A plurality of lower suspension mount assemblies couple the lower rod ends to the wash unit tub and more specifically to the tub sidewall. Each lower suspension mount assembly includes a lower suspension mount receptacle that is positioned along the tub sidewall and an upper spring seat that is positioned on the suspension rod. Exemplary lower suspension mount assemblies having lower bushings are disclosed in U.S. Patent Application Publication 2023/0212806, which is incorporated herein by reference.

It should be appreciated that the upper and lower suspension mount assemblies of the present disclosure may be incorporated into the laundry appliance separately or together on opposing ends of each suspension rod. In other words, the upper suspension mount assemblies described herein may be incorporated into a laundry appliance without inclusion of the lower suspension mount assemblies disclosed herein. Alternatively, the lower suspension mount assemblies described herein may be incorporated into a laundry appliance without inclusion of the upper suspension mount assemblies disclosed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present disclosure will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a top perspective view of an exemplary laundry appliance where the laundry appliance includes an appliance housing with a laundry compartment opening in an upper housing wall;

FIG. 2 is a top perspective view of part of an exemplary laundry appliance where the appliance housing shown in FIG. 1 has been removed to reveal several components of the laundry appliance, including an exemplary wash unit tub of the laundry appliance and exemplary suspension rod assemblies that have been constructed in accordance with the present disclosure;

FIG. 3 is a front perspective view of part of the wash unit tub and one of the exemplary suspension rod assemblies shown in FIG. 2;

FIG. 4A is a front cross-section view of an exemplary bushing of the present disclosure;

FIG. 4B is a perspective cross-section view of the exemplary bushing shown in FIG. 4A;

FIG. 5A is a front cross-section view of another exemplary bushing of the present disclosure;

FIG. 5B is a perspective cross-section view of the exemplary bushing shown in FIG. 5A;

FIG. 6A is a front cross-section view of another exemplary bushing of the present disclosure;

FIG. 6B is a front cross-section view of the exemplary bushing shown in FIG. 6A;

FIG. 7A is a front cross-section view of another exemplary bushing of the present disclosure;

FIG. 7B is a perspective cross-section view of the exemplary bushing shown in FIG. 7A;

FIG. 8A is a front cross-section view of another exemplary bushing of the present disclosure;

FIG. 8B is a perspective cross-section view of the exemplary bushing shown in FIG. 8A;

FIG. 9A is a front cross-section view of another exemplary bushing of the present disclosure;

FIG. 9B is a front cross-section view of the exemplary bushing shown in FIG. 9A;

FIG. 10A is a front cross-section view of another exemplary bushing of the present disclosure; and

FIG. 10B is a perspective cross-section view of the exemplary bushing shown in FIG. 10A.

DETAILED DESCRIPTION

Referring to the Figures, wherein like numerals indicate corresponding parts throughout the several views, an exemplary laundry appliance 22 having a hydraulic bushing that limits travel of a wash unit tub/hung mass inside a cabinet of a top load/vertical axis laundry appliance is disclosed.

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For purposes of description herein the terms “up,” “down,” “above,” “below,” “upper,” “lower,” “top,” “bottom,” “front,” “rear,” and derivatives thereof shall relate to the orientations shown in FIGS. 1-12.

The laundry appliance 22 illustrated in FIGS. 1 and 2 has a top-load configuration and includes an appliance housing 24 that is rectangular in shape. A top appliance door (not shown) may be pivotally connected to the laundry appliance 22 to open and close a laundry compartment opening 28 in the appliance housing 24. The laundry appliance 22 includes a wash unit tub 30 that is mounted inside the appliance housing 24. The wash unit tub 30 is generally cylindrical in shape but does not rotate relative to the appliance housing 24. The wash unit tub 30 is supported within the appliance housing 24 by four suspension rod assemblies 32 that give the wash unit tub 30 a limited degree of freedom, which allows the wash unit tub 30 to move/oscillate relative to the appliance housing 24 during the wash and spin cycles of the laundry appliance 22. More details regarding the suspension rod assemblies 32 is provided below. The wash unit tub 30 includes a tub opening 34 that leads to a tub cavity 36 inside the wash unit tub 30.

A drum 38 is positioned inside the tub cavity 36 and is rotatably supported within the wash unit tub 30 such that the drum 38 is rotatable with respect to the wash unit tub 30 about an axis 40. Because the laundry appliance 22 in the illustrated examples has a top-load configuration, it should be appreciated that the axis 40 extends substantially vertically (i.e., at an angle that is 80-100 degrees from horizontal). As such, the laundry appliance 22 may generally be characterized as a vertical axis washing machine. The drum 38 has a top end 42, a bottom end (not shown), and a cylindrical shape. A drum opening 46 at the top end 42 of the drum 38 provides access to a laundry compartment 48 inside the drum 38. Thus, it should be appreciated that in use, laundry (e.g., clothes, towels, and bedding) is placed inside the laundry compartment 48 where it is cleaned during a wash cycle. A drive shaft (not shown) is fixedly coupled to the bottom end of the drum 38 such that the drive shaft and the drum 38 rotate together as a single unit within the wash unit tub 30. A motor (not shown) is positioned in the appliance housing 24, beneath the drum 38, and is coupled to the drive shaft. The motor drives rotation of the drive shaft and the drum 38 relative to the wash unit tub 30 and the appliance housing 24 during operation of the laundry appliance 22, such as during wash and spin cycles.

The wash unit tub 30 includes an upper tub end 50, a lower tub end 52, and a tub sidewall 54 that extends longitudinally between the upper tub end 50 and the lower tub end 52. The tub sidewall 54 is generally cylindrical and includes four suspension support brackets 66. The suspension support brackets 66 may be fixed to or integrated in the tub sidewall 54 to provide an attachment point for the suspension rod assemblies 32, which support the wash unit tub 30 within the appliance housing 24.

The appliance housing 24 includes an upper frame 68 supporting an upper housing wall (removed in FIG. 1). The appliance door (not shown) may be pivotally mounted to the upper frame 68 and/or upper housing wall to open and close the laundry compartment opening 28. The appliance housing 24 may also include a lower frame 70 and one or more vertical walls 72 that extend between the upper and lower frames 68, 70 to form the outside surfaces of the appliance housing 24.

The wash unit tub 30 is hung from and supported by the suspension rod assemblies 32, which extend between the upper frame 68 of the appliance housing 24 and the wash unit tub 30. Each suspension rod assembly 32 includes a suspension rod 74 that extends from an upper rod end 76 to a lower rod end 78. With additional reference to FIGS. 3, the upper rod end 76 defines a hooked end 78. The hooked end 78 is defined by an approximately 90-degree bend in the suspension rod 74. It is contemplated that the bend of the suspension arm 74 may be less than or greater than 90 degrees to form the hooked end 78.

A plurality of lower suspension mount assemblies couple the lower rod ends 78 to the wash unit tub 30 and more specifically to the tub sidewall 54. Each lower suspension mount assembly includes a lower suspension mount receptacle that is positioned in the suspension support brackets 66 on the tub sidewall 54. Exemplary lower suspension mount assemblies having lower bushings is disclosed in U.S. Patent Application Publication 2023/0212806, which is incorporated herein by reference.

A plurality of upper suspension mount assemblies 80 pivotally couple the upper rod ends 76 of the suspension rods 74 to the upper frame 68 of the appliance housing 24. Each upper suspension mount assembly 80 includes a cup-shaped socket 82 that is disposed in the upper frame 68 of the appliance housing 24, a bushing 84 that is positioned on the upper rod end 76. More specifically, the upper frame 68 of the appliance housing 24 includes four corner gussets 88 and each corner gusset 88 includes one of the cup-shaped sockets 82.

As will become apparent further below, bushing 84 may be referred to as hydraulic bushing 84. The bushing 84 has a resiliency. The bushing 84 is made of a resilient material, such as rubber (e.g., ethylene propylene diene monomer (EPDM) or a like rubber) or an elastomer, for example. The bushing 84 may be formed by an injection molding process. The bushing 84 may define a generally spherical shape, however, may also define other shapes such as semi-spherical shape, an apple, pear, oval, square, rectangular, triangular or any other shape. With reference to FIGS. 4-11, bushing 84 has an outer wall 100, an inner wall 102 and a chamber dividing wall 104. The inner wall 102 defines a first channel 106 that extends, along a central axis 108, through bushing 84. The outer wall 100, inner wall 102, and chamber dividing wall 104 define and form a pumping chamber 90 and a compensation chamber 92 within the bushing 84. The pumping and compensation chambers 90, 92 are filled with fluid. The fluid may be an incompressible fluid, such as ethylene glycol or similar fluid. The pumping and compensation chambers 90, 92 may each contain the same volume or mass of fluid or differing volume or mass of fluid.

The bushing 84 further defines an upper slot 106 and a lower slot 107. In some embodiments, such as the embodiment illustrated in FIGS. 6A and 6B, the bushing 84 may not have an upper slot 106. The outer wall 100 defines an outer wall slot 200 having a depth. The depth of the outer wall slot 200 may differ among the various embodiments of the bushing 84. The slot 200 may receive a ring 202. The outer wall slot 200 may alternatively be configured to receive a portion of the upper frame 68 and therefore may couple the bushing 84 to the upper frame 68. In other words, the outer wall slot 200 may receive a portion of a corner gussets 88 or the cup-shaped socket 82 to couple the bushing 84 to the upper frame 68. Ring 202 is made of a ridged material that has a stiffness and/or hardness and/or density greater than the material comprising the bushing 84. In one embodiment, ring 202 may be formed of polyethylene terephthalate (PET or PETE) or like material. In another embodiment, ring 202 may be formed of a resilient material having a stiffness and/or hardness and/or density greater than the resilient material comprising the bushing 84.

A suspension rod support 300 is disposed in the first channel 106 in the bushing 84. The suspension rod support 300 has an upper flange 302 and a lower flange 304. The suspension rod support 300 has a sleeve 306 extending between the upper and lower flanges 302, 304. The sleeve 306 defines a second channel 308 that extends, along the central axis 108 and coaxially with the first channel, through the suspension rod support 300. The suspension rod 74 extends through the second channel 308 in the sleeve 306 in a sliding fit.

The upper and lower flanges 302, 304 extend radially outward away from the central axis 108 and are generally perpendicular to the sleeve 306 and parallel to each other. The flanges 302, 304 extend radially outward away from the central axis 108 at an angle of ninety (90) degrees or at an angle between eighty (80) and one hundred (100) degrees. The upper and lower flanges 302, 304, extend radially outward a distance from the central axis 108 to a flange end, defining a length of each respective flange 302, 304. The respective length of the upper and lower flanges 302, 304 may differ or be the same. In some embodiments, such as the embodiment illustrated in FIGS. 4A and 4B, the upper flange 304 has a length greater than the length of the lower flange 302. In other embodiments, such as the embodiment illustrated in FIGS. 5A and 5B, the lower flange 302 has a length greater than the length of the upper flange 304. The length of the upper and lower flanges 302, 304 may be configured relative to the shape, size, desired resistance, desired deflection, or any other characteristic of the bushing 84 or the suspension rod 74.

The upper flange 302 is positioned in and engages the upper slot 106 and the lower flange 304 is positioned in and engages the lower slot 107. The upper and lower flanges 302, 304 engage the upper and lower slots 106, 107 to couple the suspension rod support 300 to the bushing 84. The suspension rod support 300, generally, is formed of a material that has a stiffness and/or hardness and/or density greater than the material comprising the bushing 84. In one embodiment, the suspension rod support 300 may be formed of polyethylene terephthalate (PET or PETE) or like material. In another embodiment, the suspension rod support 300 may be formed of a resilient material having a stiffness and/or hardness and/or density greater than the resilient material comprising the bushing 84.

The bushing 84 is positioned on the upper rod end 76 and the second channel 308 receives the upper rod end 76. The upper flange 304 abuts and supports the hooked end 78 of the suspension rod 74, such that the hooked end 78 may contact and/or rest against an upper surface of the upper flange 302. The upper rod end 76 extends through the suspension rod support 300 and at least part of the bushing 84 is received in the cup-shaped socket 82 in the upper frame 68 of the appliance housing 24. In some embodiments, the outer wall slot 200 may receive a portion of a corner gussets 88 or the cup-shaped socket 82 to couple the bushing 84 to the upper frame 68. In other embodiments, ring 202 may engage, rest, or otherwise couple to the corner gusset 88 or the cup-shaped socket 82. In yet other embodiments, the lower flange 302 and a surface of the bushing 84 may rest on or couple to a portion of a corner gussets 88 or the cup-shaped socket 82.

With reference to FIGS. 4A and 4B, the chamber dividing wall 104 defines a first hydraulic passageway 400 that extends between and fluidly connects the pumping and compensation chambers 90, 92. The hydraulic passageway 400 permits fluid flow between the pumping and compensation chambers 90, 92. The first hydraulic passageway 400 is open to the pumping chamber 90 at a first hydraulic opening 402 and is open to the compensation chamber 92 at a second hydraulic opening 404. Hydraulic passageway 400 is a fluid mass channel configured to allow a mass of fluid to travel from the pumping chamber 90 to the compensation chamber 92. The hydraulic passageway 400 has a diameter and extends helically, about the central axis 108, from the first hydraulic opening 402 to the first hydraulic opening 404. The hydraulic passageway 400 has a diameter and an arc length of 180 degrees so as to form a partial helix. It should be appreciated that the hydraulic passageway 400 in this embodiment is a bore that extends entirely within the chamber dividing wall 104 and that the arc length of the hydraulic passageway 400 may vary from 90 degrees to less than 360 degrees.

During operation of the laundry appliance 22 (e.g., during wash and/or spin cycles) the wash unit tub 30 vibrates and oscillates. These vibrations and/or oscillations can be particularly noticeable or severe at a resonant frequency of the wash unit tub 30 when there is a heavy and/or unbalanced load of laundry inside the laundry compartment 48. The resilience of the bushings 84 reduce and dampen the vibrations transmitted between wash unit tub 30 and the laundry appliance 22. Specifically, the undesirable vibration and/or oscillation of wash unit tub 30 causes suspension rods 74 to move in a vertical direction relative to the appliance housing 24, thereby transmitting compression forces to upper rod ends 76.

The compression forces transmitted to upper rod ends 76 are than transmitted to the bushings 84, compressing the bushings 84 and causing fluid to flow from the pumping chamber 90, through hydraulic passageway 400, into the compensation chamber 92. The flow of fluid through the hydraulic passageway 400 between the pumping and compensation chambers 90, 92, among other factors, provides additional resilience to the bushings 84. Advantageously, the resilience of the bushings 84 reduces and/or dampens the vibrations and oscillations between upper rod ends 76 and the upper frame 68 of the appliance housing 24. Ultimately, the resilience of bushings 84 reduces the amount of noise and vibration that can be perceived from outside the laundry appliance 22.

The vibrations and/or oscillations of wash unit tub 30 transmits a frequency of forces to the bushings 84. When the forces applied to the bushings 84 are at or above a resonance frequency, the bushings 84 become stiffer. At or above the resonance frequency, fluid flows through the hydraulic passageway 400 from the pumping chamber 90 to the compensation chamber 92, causing the stiffness of the bushings 84 to increase. In some embodiments, as the stiffness of the bushings 84 increase, the outer wall 100 may bulge. When forces are applied below the resonance frequency, the stiffness of the bushings 84 remain relatively constant. Below the resonance frequency, fluid flow through the hydraulic passageway 400 is limited due to the helical configuration of the hydraulic passageway 400 about the central axis 108.

The hydraulic passageway 400 defines a channel resonance frequency, wherein the channel resonance frequency acts as an on-off switch allowing fluid to pass through the hydraulic passageway 400 between the pumping and compensation chambers 90, 92. The channel resonance frequency is defined by the diameter or taper angle, length, and pitch (relative to the hydraulic passageway 400 extending helically about the central axis 108) of the hydraulic passageway 400. The channel resonance frequency is configured to match the resonance frequency of the vibrations and/or oscillations of wash unit tub 30 such that the hydraulic passageway 400 opens, allowing fluid to pass between the pumping and compensation chambers 90, 92, such that the bushing 84 becomes stiffer when the resonance frequency of the wash unit tub 30 is met or exceeded. In turn, the bushings 84 reduce the amount of noise and vibration that can be perceived from outside the laundry appliance 22 by becoming stiffer and preventing undesired transfer for vibration or oscillation from the wash unit tub 30 to the appliance housing 24.

With reference to FIGS. 5A and 5B, the chamber dividing wall 104 contains a hydraulic passageway 500 that extends helically about the central axis 108, forming a coil shape having two coils. The coils have a constant radius measured radially from the central axis 108 to the hydraulic passageway 500. The hydraulic passageway 500 extends through said chamber dividing wall 104 between a first hydraulic opening 502 that communicates with the pumping chamber 90 and a second hydraulic opening 504 that communicates with the compensation chamber 92. The hydraulic passageway 500 has a greater length than hydraulic passageway 400, causing hydraulic passageway 500 to have a channel resonance frequency different than the channel resonance frequency of the hydraulic passageway 400. As a result, the chamber dividing wall 104 in this embodiment has a variable thickness to accommodate the greater height of the hydraulic passageway 500.

With reference to FIGS. 6A and 6B, the chamber dividing wall 104 contains a hydraulic passageway 600 that extends helically about the central axis 108, forming a coil shape having three coils. The hydraulic passageway 600 extends through said chamber dividing wall 104 between a first hydraulic opening 602 that communicates with the pumping chamber 90 and a second hydraulic opening 604 that communicates with the compensation chamber 92. The coils have a variable radius that is measured radially from the central axis 108 to the hydraulic passageway 600, which gradually decreases moving from the first hydraulic opening 602 to the second hydraulic opening 604. However, it should be appreciated that this arrangement could be inverted, where the variable radius gradually increases moving from the first hydraulic opening 602 to the second hydraulic opening 604. The hydraulic passageway 600 has a greater length than hydraulic passageways 400, 500, causing hydraulic passageway 600 to have a channel resonance frequency different than the channel resonance frequency of hydraulic passageways 400, 500.

With reference to FIGS. 7A and 7B, the chamber dividing wall 104 contains a hydraulic passageway 700 that extends about the central axis 108 in a partial helix from a first hydraulic opening 702 to a second hydraulic opening 704. The hydraulic passageway 700 has a greater length and a smaller diameter than hydraulic passageways 400, causing hydraulic passageway 700 to have a channel resonance frequency different than the channel resonance frequency of hydraulic passageways 400.

With reference to FIGS. 8A and 8B, the chamber dividing wall 104 extends radially inwardly from the outer wall 100, but ends before reaching the inner wall 102, creating an annular gap between inner wall 102 and the chamber dividing wall 104 that defines hydraulic passageways 800.

With reference to FIGS. 9A and 9B, the chamber dividing walls 104 includes multiple hydraulic passageways 900 that extend longitudinally through the chamber dividing wall 104. In accordance with this embodiment, the hydraulic passageways 900 have an hour-glass shape.

With reference to FIGS. 10A and 10B, hydraulic passageway 1000 is a tubular, straw-like structure that extends about the central axis 108 in in a partial helix from a first hydraulic opening 1002 to a second hydraulic opening 1004. The hydraulic passageway 1000 extends from the pumping chamber 90, through the chamber dividing wall 104, and into compensation chamber 92 such that portions of the hydraulic passageway 1000 protrude from and are positioned within the pumping and/or compensation chambers 90, 92. In the compensation chamber 92, the hydraulic passageway 1000 may be spaced from the chamber dividing wall 104 as the hydraulic passageway 1000 extends helically about axis 108. The hydraulic passageway 1000 may be integrally formed with the bushing 84 or may be a separate straw-like component.

Many modifications and variations of the apparatus and assemblies described in the present disclosure are possible in light of the above teachings and may be practiced otherwise than as specifically described while within the scope of the appended claims. These antecedent recitations should be interpreted to cover any combination in which the inventive novelty exercises its utility.