Hydraulic Bushing For A Top Load Washing Machine

Abstract

A laundry appliance comprising an appliance housing and a wash unit tub that is disposed inside the appliance housing. A plurality of suspension rod assemblies having a suspension rod hanging and supporting the wash unit tub from the appliance housing. Upper suspension mounts having a bushing positioned between the suspension rod and the appliance housing. Each bushing has a hydraulic passageway that extends helically about a first axis and fluidly connects a pumping chamber and a compensation chamber. Each bushing is resilient and configured to reduce and dampen vibrations transmitted between the suspension rod and the appliance housing.

What is claimed is: 
     
         1 . A laundry appliance, comprising:
 an appliance housing having an upper frame;   a wash unit tub disposed inside said appliance housing;   a drum rotatably supported within said wash unit tub;   a plurality of suspension rod assemblies extending between said upper frame of said appliance housing and said wash unit tub such that said wash unit tub is hung from and supported by said plurality of suspension rod assemblies;   each of said suspension rod assemblies including a suspension rod that extends from an upper rod end to a lower rod end;   a plurality of upper suspension mounts coupling said upper rod end of each one of said suspension rods to said upper frame of said appliance housing;   each of said upper suspension mounts having a bushing positioned between said upper rod end and said upper frame of said appliance housing;   each of said bushing being resilient and configured to reduce and dampen vibrations transmitted between said upper rod end and said upper frame of said appliance housing;   said bushing having a chamber dividing wall that divides an interior of said bushing into a pumping chamber and a compensation chamber; and   a hydraulic passageway that extends between and fluidly connects said pumping chamber and said compensation chamber.   
     
     
         2 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway extends from and between a first hydraulic opening that is open to said pumping chamber and a second hydraulic opening that is open to said compensation chamber. 
     
     
         3 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway has a diameter, a length, and a pitch that are configured to define a channel resonance frequency. 
     
     
         4 . The laundry appliance as set forth in  claim 3 , wherein said hydraulic passageway permits fluid flow between said pumping and compensation chambers when forces applied to said bushing are at frequency at or above said channel resonance frequency. 
     
     
         5 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway extends through said chamber dividing wall and forms a partial helix with an arc length that is more than 90 degrees and less than 360 degrees. 
     
     
         6 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway extends through said chamber dividing wall and helically about a first axis to form a coil shape having at least two coils. 
     
     
         7 . The laundry appliance as set forth in  claim 6 , wherein said coils of said hydraulic passageway have a constant radius moving from said pumping chamber to said compensation chamber. 
     
     
         8 . The laundry appliance as set forth in  claim 6 , wherein said coils of said hydraulic passageway have a variable radius moving from said pumping chamber to said compensation chamber. 
     
     
         9 . The laundry appliance as set forth in  claim 8 , wherein said variable radius of said coils decreases moving from said pumping chamber towards said compensation chamber. 
     
     
         10 . The laundry appliance as set forth in  claim 8 , wherein said variable radius of said coils increases moving from said pumping chamber towards said compensation chamber. 
     
     
         11 . The laundry appliance as set forth in  claim 1 , wherein said bushing has an outer wall defining an outer wall slot that is configured to receive said upper frame to couple said bushing to said upper frame, and wherein said bushing has an inner wall defining a first channel that extends, along an axis extending through said bushing, and said first channel receives a suspension rod support. 
     
     
         12 . The laundry appliance as set forth in  claim 11 , wherein said hydraulic passageway is defined as an annular gap between said chamber dividing wall and said inner wall. 
     
     
         13 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway has a diameter and a length that are configured to define a channel resonance frequency. 
     
     
         14 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway is defined as a bore that extends entirely within said chamber dividing wall. 
     
     
         15 . The laundry appliance as set forth in  claim 1 , wherein said hydraulic passageway is a tubular, straw-like structure that passes through and protrudes from said chamber dividing wall into at least one of said pumping and compensation chambers. 
     
     
         16 . The laundry appliance as set forth in  claim 1 , wherein said bushing has an outer wall of an elastic material that is configured to allow said outer wall to bulge when a force is applied to said bushing. 
     
     
         17 . A laundry appliance, comprising:
 an appliance housing;   a wash unit tub disposed inside said appliance housing;   a plurality of suspension rod assemblies extending between said appliance housing and said wash unit tub such that said wash unit tub is hung from and supported by said plurality of suspension rod assemblies;   each of said suspension rod assemblies including a suspension rod that extends from an upper rod end to a lower rod end;   a plurality of upper suspension mounts coupling said upper rod end of each one of said suspension rods to said appliance housing; and   each of said upper suspension mounts having a bushing positioned between said upper rod end and said appliance housing;   said bushing is resilient and configured to reduce and dampen vibrations transmitted between said upper rod end and said upper frame of said appliance housing;   said bushing having a pumping chamber and a compensation chamber;   said bushing having a hydraulic passageway that extends between and fluidly connects said pumping chamber and said compensation chamber;   said hydraulic passageway has a channel resonance frequency; and   said hydraulic passageway permits fluid flow between said pumping and compensation chambers when forces applied to said bushing are at a frequency at or above said channel resonance frequency.   
     
     
         18 . The laundry appliance as set forth in  claim 17 , wherein said hydraulic passageway forms a partial helix with an arc length that is more than 90 degrees and less than 360 degrees and said arc length further defines said channel resonance frequency. 
     
     
         19 . The laundry appliance as set forth in  claim 17 , wherein said hydraulic passageway has a coil shape formed of at least two coils. 
     
     
         20 . A laundry appliance, comprising:
 an appliance housing having an upper frame;   a wash unit tub disposed inside said appliance housing;   a drum rotatably supported within said wash unit tub;   a plurality of suspension rod assemblies extending between said upper frame of said appliance housing and said wash unit tub such that said was unit tub is hung from and supported by said plurality of suspension rod assemblies;   each said suspension rod assemblies including a suspension rod that extends from an upper rod end to a lower rod end;   a plurality of upper suspension mounts pivotally coupling said upper rod end of each one of said suspension rods to said upper frame of said appliance housing; and   each said upper suspension mounts having a bushing positioned between said upper rod end and said upper frame of said appliance housing;   said bushing having a chamber dividing wall that divides an interior of said bushing into a pumping chamber and a compensation chamber;   each said bushing is resilient and configured to reduce and dampen vibrations transmitted between said upper rod end and said upper frame of said appliance housing;   said chamber dividing wall defines a hydraulic passageway that extends, helically about a first axis and fluidly connects said pumping chamber and said compensation chamber;   said hydraulic passageway extends from and between a first hydraulic opening open to said pumping chamber and a second hydraulic opening open to said compensation chamber;   said hydraulic passageway permits fluid flow between said pumping and compensation chambers when forces are applied to said bushing are at frequency at or above said channel resonance frequency; and   said hydraulic passageway forms a partial helix with an arc length that is more than 90 degrees and less than 360 degrees and said arc length further defines said channel resonance frequency.