Patent Application
20070289088
The accompanying drawing incorporated in and forming a part of this specification illustrates several aspects of the present invention and together with the description serves to explain certain principles of the invention. In the drawing:
a is a detailed, transverse cross sectional and schematical view illustrating the airflow passage maintained between the bag cage, the filter bag held in the bag cage and the right side, left side, front and rear surfaces of the bag compartment wall;
b is a detailed, longitudinal cross sectional and schematical view illustrating the airflow passage maintained between the bag cage and the right side, left side, top and bottom surfaces of the bag compartment wall;
Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings.
Reference is now made to
The vacuum cleaner 10 includes a housing, generally designated by reference numeral 12, including a nozzle section or assembly 14 and a canister section or assembly 16. As is known in the art, the canister section 16 is pivotally connected to the nozzle section 14 to aid the operator in manipulating the vacuum cleaner 10 back and forth across the floor. Wheels 17 (only one illustrated in
As best illustrated in
During the cleaning operation the rotary agitator 20 brushes and beats dirt and debris from the nap of an underlying carpet being cleaned. The dirt and debris are then drawn by the suction generator 22 through the suction inlet 18, the airflow inlet 25, the filter bag 26 in the bag compartment 24 and the secondary filter 28 that is provided across the airflow outlet 30. Dirt and debris are collected in the filter bag 26 and fine debris is screened by the secondary filter 28. The airstream is then directed through the motor of the suction generator 22 to provide cooling before being routed through a final filter (not shown), to remove any carbon particles stripped from the brushes of the motor by the airstream, before exhausting the airstream through an exhaust port 34 into the environment.
As best illustrated in
An inlet fitting 60 in the rear surface 54 of the bag compartment wall 42 defines the airflow inlet 25 into the bag compartment 24. The airflow outlet 30 is provided in the bottom surface 46 of the bag compartment wall 42. A secondary filter 28, such as a fine screen, polymeric filter media or the like, extends across the airflow outlet 30 so as to capture any fine dirt and debris that might pass through the filter bag 26 in the bag compartment 24 and thereby prevent its passage into the motor of the suction generator 22.
A bag cage, generally designated by reference numeral 64, defines a cavity 66 for receiving and holding the filter bag 26. In the illustrated embodiment, the bag cage 64 includes a first section 68, which accommodates the inlet fitting 60 and is secured to the housing section 38 or 40 by means of struts 61, and a removable bag caddy 70 (see
As further shown in
As should be appreciated, the bag cage 64 is fully received in the bag compartment 24. The cavity 66 defined by the bag cage 64 has a first volume of between about 4.0 liters and about 7.5 liters and the bag compartment 24 has a second volume of between about 5.5 liters and about 10.5 liters. Typically, the volume of the bag cavity 66 is between about 40 and about 80 percent of the volume of the bag compartment 24.
As best illustrated in
During vacuum cleaner operation, as air entrained with dirt and debris is drawn by the suction generator 22 from the suction inlet 18 through the airflow inlet 25 into the filter bag 26, the filter bag 26 expands and is held up against the bag cage 64. The bag cage 64 prevents the filter bag 26 from expanding into engagement with any surface 44, 46, 48, 50, 52 and 54 of the bag compartment wall 42 thereby positively maintaining the airflow passage 72 all the way around the filter bag. Advantageously, the airflow passage 72 provides a continuously free and open air path for clean air to be drawn quickly through the entire circumferential surface area of the filter bag 26 even as the filter bag fills with dirt and debris. As a consequence, the suction generator 22 is never forced to draw the majority or all of the air through the dirt and debris collecting in the bottom of the filter bag 26. As such, airflow is not significantly diminished by the collected dirt and debris and cleaning efficiency is maintained at high levels even as the filter bag 26 fills. Further, suction air velocity remains high at all times even as the filter bag 26 fills with dirt and debris.
In contrast, in bag vacuum cleaners of prior art design, the filter bag has a tendency to expand into engagement with the sidewalls of the bag compartment thereby effectively sealing and substantially preventing the free passage of air through the sidewall of the filter bag. As a consequence, the air being drawing through the vacuum cleaner by the suction generator is forced to travel through the dirt and debris in the filter bag toward the air flow outlet. The dirt and debris interferes with the free passage of the air thereby reducing the air velocity and, accordingly the cleaning power of the vacuum cleaner as the air bag fills with the dirt and debris. This problem is effectively avoided utilizing the cooperating bag cage 64 and the bag compartment 24 of the vacuum cleaner of the present invention.
It should be appreciated that the bag cage 64 is greater than 50% open space in order to promote free airflow. Further, the volume V1 of the bag cavity 66, the volume V2 of the bag compartment 24, the cross sectional area Ai of the airflow inlet 25, the cross sectional area Ap of the portion of the airflow passage 72 between the bag cage and the bag compartment wall and the cross sectional area Ao of the airflow outlet are all designed to function together in order to insure clean and efficient airflow from the time the filter bag is empty to the time it is full and ready for changing.
When it becomes necessary to service the filter bag 26, the access door 80 of the canister housing member 38 is removed from the vacuum cleaner 10 so as to expose the bag caddy 70 of the bag cage 64. The bag caddy 70 is then removed from the first section 68 of the bag cage 64 so as to allow the operator access to the filter bag 26. More specifically, the handle 71 is pivoted upwardly in the direction of action arrow A about the pivot pins 75 to release the lugs 73 from the mating structure and free the bag caddy 70 for removal. The operator may then conveniently carry the dirty bag 26 by the handle 71 to a garbage can or the like. The bag collar 69 is then slipped from the bag holder 67 and the dirty bag 26 is thrown away.
Next, the bag collar 69 of a clean filter bag 26 is placed in the bag holder 67 with the filter bag extending down between the main body of the bag caddy 70 and the bag holder. The bag caddy 70 is then repositioned to mate with the first section 68 of the bag cage 64 with the bag 26 fully received in the bag cavity 66. The handle is then pivoted downwardly to bring the lugs 73 in place to lock the bag caddy 70 in position. Next the door 80 is replaced on the vacuum cleaner 10 so as to properly mate with the section 38. The vacuum cleaner 10 is then once again ready for use.
The foregoing description of a preferred embodiment of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. For example, the canister vacuum cleaner illustrated in
The embodiment was chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. The drawings and preferred embodiments do not and are not intended to limit the ordinary meaning of the claims and their fair and broad interpretation in any way.
