|Publication number||US2475808 A|
|Publication date||Jul 12, 1949|
|Filing date||Sep 24, 1945|
|Priority date||Sep 24, 1945|
|Publication number||US 2475808 A, US 2475808A, US-A-2475808, US2475808 A, US2475808A|
|Inventors||Jr Frederick K Storm|
|Original Assignee||Jr Frederick K Storm|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (13), Referenced by (56), Classifications (17)|
|External Links: USPTO, USPTO Assignment, Espacenet|
July 12, 1949. F. K. STORM, JR
SELF-CONTAINED SUCTION CLEANER 2 Sheets-Sheet 1 Filed Sept. 24, 1945 K Swen/1,112
July 12, 1949. F. K. STORM, JR
v SELF-CONTAINED SUCTION CLEANER 2 Sheets-Sheet 2 Filed Sept. 24, 1945 ike'aee/cz K 5 men, Mk
I N V EN TOR.
ATTOENA'K Patented July 12, 1949- I UNITED STATES PATENT OFFICE SELF-CONTAINED suc'nou cnnmnn Frederlck'K. Storm, In, Los Angeles, Calif.
Application September 24, 1945, Serial No. 618,210
' 4 Claims. (01. 15-346) This invention pertains to improvements in vacuum cleaners and is particularly directed to a low, compact, bagless, self-contained vacuum cleaner in which air ducts are arranged so as to efiiciently separate foreign matter picked up by the vacuum cleaner from the air stream in which such foreign matter is carried. I
The art of vacuum cleaners may be traced back to street-cleaning machines and since early times attempts have been made to recirculate the air used in picking up foreign objects. from the ground. After the dirt or foreign objects had been separated from the air stream such air stream was supposed to be returned to the suction nozzle. A household sweeper must be low' and compact so as to be able to be used beneath rungs of chairs, under beds, in corners, etc. it must be suiiieiently light in weight and compact so that a housewife may readily and easily move the device. Moreover, the arrangement of. ducts within the machine must be such that lint and dust may be 'geifectively picked up from carpets, rugs, etc., and
Q bagless recirculating type may be formed by emrelationship, the overall height of the vacuum cleaner'is materially reduced and by providing the fan with a pair of opposing outlets, the air withdrawn from the rear chamber (through the air filter) is emciently returned to the sweeper port.
It is an object of the present invention, therefore, to provide an improved type of vacuum ploying two, spaced, substantially parallel suction ducts and a single return duct, the minimum cross-sectional area of the: suction ducts being approximately twice as great as the minimum uum cleaner. would discharge considerable quantitles of air into the room being cleaned, in actual practice no such dissemination of dust is observed and instead an efllcient cleaning of floors,
rugs and carpets is attained. Moreover, by positioning the suction ducts on opposite sides of the main housing of the vacuum cleaner and causing such suction ducts to communicate a virtually flat, transversely extending sweeper port witha (approximating a segment of a spherical zone in I Fig. 1.
cleaner which is low, compact and self contained.
A further object of the invention is to provide a bagless, self-contained vacuum cleaner in which a plurality of suction ducts are utilized, these ducts discharging into a relatively large, rounded, dust-collecting chamber whereln'centrifugal force and opposing air currents efficiently remove dust from the air streams and permit such air streams to be withdrawn as a single,clean, air stream for,
use in picking up additional dirt.
A still further object is to provide a vacuum cleaner including a pair of horizontally spaced, substantially parallel duct means for simultaneously' admitting two cofluent streams of dustladen air into opposite sides of a single dust-collecting chamber, and a single suction means, positioned between said ducts, for withdrawing dust-free air from the dust-collecting chamber in a direction opposed to the direction of flow of dust-laden air through the ducts.
Again, an object of the invention is to disclose and provide a method of operation whereby dust may be removed from streams of dust-laden air I Fig. 1 is a side elevation of the vacuum cleaner,
the handle and lead-in wires being omitted.
Fig. 2 is a front view of the device shown in Fig. 3 is a longitudinal section taken along the plane III-III of Fig. 2, the motor, fan and a general form), and by withdrawing the air thus 1 wardly extending zone or chamber while the air.
is returned to the suction port. Furthermore, by positioning a motor, fan and air filter in aligned, horizontally disposed, longitudinally extending filter being shown in elevation.
Fig. 4 is a ,plan view with a part of the cover broken away.
Fig. 5 is a transverse section taken along the plane V-V in Fig. 3. Fig. 6 is a transverse section taken along the plane VI-VI in Fig. 3.
It will be evident from Figs. 1, 2 and 4 that the vacuum cleaner of the present invention is relawws vely low and flat, and is provided with a substantially straight front and rounded rear portion. The housing or case of the vacuum cleaner may be contoured in a variety of ways and in so far as the present invention is concerned, the contours of the front portion of the vacuum cleaner are not important. It is essential, however, that the front portion be provided with a substantially flat, horizontal, transversely extending sweeping port and that the rear portion of the vacuum cleaner form a rounded chamber approximating the shape of one-half of a spherical segment.
In the example illustrated, the device includes a base I, the frontal portion of such base having upstanding sides 2, an upwardly curving front edge portion 3, and a transversely extending, horizontal sweeping port 4. The base i may be provided with an upwardly inclined portion 5 leading to a vertically disposed step 6, the base then continuing rearwardly in a virtually horizontal plane as indicated at 1. Suitable supporting wheels may be provided at 8, 9 and ID. The wheels 8 and I may bemid way of the sides of such base, whereas the wheels 9 may be positioned adjacent the sides of the base.
The housing is suitably attached to this base and may include a rearwardly curving front portion II, a substantially horizontal top I2, and rearwardly extending sides l3 and I4, these sides curving upwardly and inwardly so as to form a rounded rear portion, generally indicated at l5.
This rounded rear portion l5 may be separable from the rest of the housing and be parted therefrom along a line of juncture l6. Moreover, this rounded rear portion i5 may be connected to a bottom I! adapted to rest upon or interlock with the rearward extension 1 of the base The bottom |'I may be provided with an upstanding frontal lip I8 adapted to abut the step 6 formed in thebase member In effect, therefore, the rear, rounded, dust-collecting portion of the vacuum cleaner (including the members i5, i1 and I8) constitutes a dust pan which may be removably connected to the rest of the device in any suitable manner.
The vacuum cleaner is provided with a pair of horizontally. extending, substantially parallel, transversely spaced duct means for simultanestreams of dust-laden air from the sweeping portion 4 into the dust-collecting chamber in the rear of the vacuum cleaner. Such ducts are generally indicated at 2| and 22, the bottom of such ducts being formed bythe portion 5 of the base whereas the top of such ducts consists of the virtually horizontal, transversely extending partition members 23 and 24. The frontal portions of such partition members 23 and 24 merge above the sweeper port 4 into a downwardly and rearwardly curving edge portion 25 spaced from the upwardly curving edge portion 3 of the base and the front housing The rearward edge of these virtually horizontal, transverse partitions 23 and 24 merge with or are connected to a substantially vertical, transverse partition 21 positioned within the middle third of the entire device.- The transverse partition 21 does not extend below the horizontal partitions 23 and 24.
The transverse partition 21 is provided with an axial port over which a suitable air filter or air cleaner 28 may be removably attached as, for example, by means of a bayonet point fitting 29. In the drawings, the air filter is shown provided ously admitting two substantially parallel cofluent cameos 4 with a porounwoven, wire pad or filtering surface. 7
The lower suction ducts 2i and 22 are spaced and separated by a mounting block which supports a motor 34. The mounting block may either be solid or may comprise a virtually U- shaped extension of the motor housing, such downward extension being connected to the base member I as indicated at 33'. The motor 3. is provided with a fan 3| having an axial inlet cooperating with the port in the transverse vertical partition 21. The motor 20, fan II, and air filter 28 are therefore in alignment and are centrally positioned with respect to the side walls of the device. The fan 3| is provided with a pair of opposed outlets, such as 32, such outlets discharging into the return duct forwardly of the transverse partition 21 and above the substantially horizontal partitions 23 and 24.
The motor 30 not only drives the fan 3| but also may be used to drive a brush carried upon a shaft 33 journaled in vertically adjustable bearings mounted in levers 34 attached to the sides 2 of the base member i. Since the suction ducts 2| and 22 should not contain dead air spaces, Fig. 3 shows a filler 35 carried by the lower surface of the partitions 23 and 24 immediately in the rear of the upper portion of the brush. The brush may be driven by means of a flexible belt 31 from the shaft of the motor 30.
It will be noticed that in the arrangement described the suction ducts 2| and 22 direct the dust-laden air tangentially into the rounded, rear, dust-collecting zone 20 and discharge into such zone at opposite sides thereof. In this manner the dust-collecting zone 24 is concurrently supplied with two virtually parallel streams of dust-laden air flowing in the same general direction. These two streams of air are caused to turn toward one another by reason of the rounded, curving rear portion ii of the housing. Simultaneously, air is'withdrawn from the dustcollecting chamber at a central point through the air cleaner.
As shown in Fig. 4, therefore, dust-laden air enters the dust-collecting chamber as indicated by the arrows 40 and 40, dust and large foreign particles continuing along the walls of the dustcollecting chamber in opposing directions as indicated by the dash lines 4| and 4|, whereas the air and some fine dust quickly reverse their direction as indicated by the arrows 42 and 42' and are moved frontally through the air cleaner and fan as indicated by the arrows 43. The heavy dust will be found to collect in the rear, rounded portion of the housing or dust-collecting chamher. A very small amount of light dust will be found on the surfaces of the air cleaner. The centrifugal motion imparted to the dust-laden air throws dust particles out of the air streams and thereby reduces the load upon the air filter. It will be noticed that a complete reversal in direction of the air streams is obtained in substantially the same plane horizontally.
The clean air returned above the transverse partitions 23 and 24 is directed by the front curving portion of the housing I] onto and across the sweeper port 4. It may be noted that this return duct is of narrowest or smallest cross-section adjacent the sweeper port. For some reason not fully understood it has been found desirable that suction ducts 2| and 22 be of smallest cross-sectional area at their point of discharge into the enlarged dust-collecting chamber 24.
Moreover, it has been found that the crosssectional area of each of the suction ducts (at its zone of minimum area) should be substantially the same as the minimum area of the return duct I so that the two suction ducts have a cross-sectional area approximately twice as great as the cross-sectional area of the return duct at its minimum. The area of the sweeper port does not appear to be critical and exceeds the total minimum areas of both suction ducts and return duct.
It will be obvious to those skilled in the art that the details of construction shown incidentally in the drawings appended hereto may be materially varied. The essential characteristics of the present invention lie in the provision of a pair of substantially parallel spaced suction ducts discharging simultaneously in opposing tangential 1 directions into a common, rounded, enlarged,
dust-collecting chamber from which air is removed at a centrally positioned zone spaced from the side walls, top and bottom of the dust-collecting chamber, so that the two incoming, dust-laden air streams discharge heavier particles by centrifugal action and opposition along the walls of the rounded, dust-collecting chamber, while a single clean air stream is discharged from such chamber in a direction directly opposed to the direction of movement or the incoming dustladen streams.
Although the method of operation has been described as it specifically pertains to vacuum cleaners of the household type, the same mode of operation may also be used in dust collectors or air cleaners of a stationary type and not of the portable type required for a vacuum cleaner.
All changes and modifications coming within the scope of the appended claims are embraced thereby.
1. A compact, low, self contained vacuum cleaner comprising: a housing having a substantially straight transverse front portion and rearwardly extending sides, said sides curving upwardly and inwardly to form a rounded rear portion; a base for said housing, said base having a frontally positioned, transversely extending sweeping port; a portion of the side walls constituting the rounded rear portion of the vacuum cleaner being integral with a bottom for said rounded rear portion and selectively removable from the vacuum cleaner; a pair of substantially parallel spaced suction ducts within the housing, the suction ducts communicating the sweeper port with opposite sides of the rounded rear portion, the said rounded portion directing the air fiow from the suction ducts in opposite and opposing directions; means including a motor, fan and air filter in horizontal, axial, longitudinal alignment within the housing, said air filter extending into the rounded rear portion but spaced from the walls thereof, whereby foreign matter carried by air streams entering the rear portion through said parallel spaced ducts is deposited in the rounded portion while the air is axially and forwardly withdrawn from the rear portion through said air filter; and a return duct within the housing extending from said fan to a position in advance of the sweeper port for returning the air and distributing the same along the transverse width of said sweeper port.
2. In a vacuum cleaner including a housing having a front portion and a rear portion, said rear portion having sides curving upwardly and inwardly to form a rounded rearwall for said housing. a base for said housing, a transversely extending sweeping port adjacent the forward end of said base, a rotatable brush mounted above and extending within said sweeping port, a pair of longitudinally extending transversely spaced suction ducts connecting the. said sweeping port with opposite sides of the said rear portion of said housing to cause the air fiow from the suction ducts to oppose one another, means for setting up a suction of air through said ducts and rotating said brush, an air filter associated with said means, and a single return duct connecting the said rear portion of said housing with the said sweeping port, the said return duct terminating in a transversely rearwardly extending jetting port located within said housing and above the lowermost plane of said sweeping port.
3. A compact, low, self-contained vacuum cleaner comprising: a housing having a substantially straight transverse front portion and rearwardly extending sides, said sides curving upwardly and inwardly to form a rounded rear portion; a base for said housing, said base having a frontally positioned transversely extending sweeping port; a pair of substantially parallel spaced suction ducts within the housing, the suction ducts communicating the sweeper port with opposite sides of the rounded rear portion to cause the air fiow from the suction ducts to oppose one another; an air filter unit centrally positioned and longitudinally disposed in the rear portion and spaced from the walls thereof; a single return duct in communication with the frontal portion of the sweeper port and overlying the suction ducts; a motor and an associated fan, said motor, fan and air filter unit being disposed in horizontal, axial, longitudinal alignment within the housing, said fan including an axial inlet in communication with the air filter unit and including outlets in communication with the return duct, foreign matter carried by the air stream from the suction ducts being deposited in the rounded rear portion while the air stream returns through the filter, fan and return duct to the sweeper port.
4. A vacuum cleaner of the character stated in claim 3, characterized in that the area of each of the suction ducts at its minimum crosssection is at a ratio of about 1:1 to the minimum cross-sectional area of the return duct adjacent the sweeper port.
' FREDERICK K. STORM, J 11.
REFERENCES CITED The following referenlces are of record in the file of this patent:
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|U.S. Classification||15/346, 15/324, 15/383, 15/412, 55/498, 15/352, 55/DIG.300|
|International Classification||A47L5/14, A47L5/30, A47L9/12|
|Cooperative Classification||A47L5/14, A47L5/30, Y10S55/03, A47L9/127|
|European Classification||A47L9/12D, A47L5/30, A47L5/14|