USRE22445E - Suction cleaner - Google Patents

Description

' M. D. STAHL SUCTION CLEANER Feb; 22, 1944.

Original Filed April 8, 1939 2 Sheets-Sheet 1 Maurice Stal ATTORNEY Feb. 22, 1944. D. STAHL 22,445

SUCTION CLEANER Original Filed April 8, 1959 2 Sheets-Sheet 2 INVENTOR Maurice fl. Slalzl ATTORNEY Reissued Feb. 22, 1944 Re. 22, i45

22,445 suc'rlou CLEANER Maurice D. Stahl, North Canton, Ohio, assignor to The Hoover Company, North Canton, Ohio, a

corporation of Ohio Original No. 2,260,237, dated October 21, 1941, Se-

rial No. 266,721, April 8, 1939. Application for reissue April 20, 1942, Serial No. 439,779

11 Claims. (01; 183-36) This invention relates to improvements in suction cleaners and more particularly to an improved form of mufiler for suction cleaners'serving to reduce thenois'e due to the rush of air through the suction system.

One practical method of reducing so-calledairflow noises is to provide a muliier extending beyond the outlet from the fan chamber and con sisting of a tubular member lined with a suitable absorbing material. However, there are certain practical limitations in the use of mufflers, particularly when adapted to a cleaner having a pivotally mounted handle supporting the outer end of a'dirt bag; In such an arrangement, the muffler extended within the dirt bag becomes a definite obstruction to the free movement thereof as it swings with the handle unless the mufiler be made s'ufliciently flexible to bend with the bag and then it is very likely to kink, thus closing ofi the discharge passage entirely. I

Therefore, the object of the present invention is to provide an improved mufiler arrangement whereby the efiective area of sound-absorbing surface is'obtained without unduly extending its length into the dirt bag. Briefly, this result is obtained by including a portion of the muffler within the exhaust passage leading from the fan chamber and connecting it with the external portion through an intermediate flexible section, so that the muffler becomes an articulated unit. And aside from the advantage of decreased length of mufller throughout its external portion, there is the further novel feature of treating the normal cleaner exhaust passage for noise-reduction for it is in this region that a considerable part of the noise is created, due to the; turbulence set up by the sudden change of velocity of the air leaving the fan chamber.

A preferred embodiment of the invention will now be described in connection with the accompanying drawings, in which:

Figure 1 is a general view in side elevation of atypical suction cleaner with portions'broken away to show the suction system and the articulated mufll'er arrangement;

Figure '2 isa viewsimilarto Figure '1 showing the dirt bag and muffler assembly removed from thecleaner;

Figure 3 is a top plan view of the rear end portion of the cleaner with portions broken away to show themuffier arrangement;

Figure 4 is a'view inside elevation of the rearmost sectionof the cleaner showing a modified arrangement in 'which'the dirt bag is mounted upon the outer section of themufiler rearwardly of the flexible section rather than forwardly thereof as shown in Figure 1.

The suction cleaner herein disclosed and to which the improved articulated mufller is particularly adapted, is of the standard design wherein the cleaner body is supported upon wheels to be .maneuvered over the carpet surface by means of a handle" having pivotal connection with the cleaner body.

The cleaner comprises generally, a casing I supported upon pairs of front and rear wheels 2, 2 and includes a nozzle portion 3 extending across its forward end. A fan chamber 4, located centrally of the' casing I; houses a fan 5 driven by" a motor concealed beneath the removable dome-like cover 6 supported upon the casing I. The handle 1 is provided at its lower end with an inverted U-shaped bail la which straddles the motor cover 6 and has pivotal connection with the cleaner'casing. The handle is free to swing forwardly and rearwardly as the cleaner is maneuvered over the carpet surface with the customary reciprocating motion. Referring now in greater detail to the suctioncreating system, the nozzle portion 3 has the form of a chamber with a downwardly opening suction mouth and is normally spaced in cleaner operation in close proximity to the carpet surface, An air passage extends rearwardly from the nozzle chamber and communicates with the fan chamber through an annular inlet opening or eye 4a in its bottomwall. By preference, a rotary carpet-contacting member 8 is mounted in the nozzle chamber and is driven by means of a belt'B extending rearwardly through the 'air passage from the nozzle and having driving connection with the fan 5 through a pulley 10 formed at the lower end -of an extension 50. 'of the fan hub.

Extending rearwardly'from' the fan chamber and-slightly oblique to the longitudinal center line of the cleaner body is the exhaust passage I I through which the dirt-laden air is discharged into a dirt bag 12 of the usual porous fabric construction having its lower end detachably connected to the discharge outlet of the fan chamber and its outer end suspended from the handle 1. The extreme rear end of the exhaust passage II is preferably flanged at llato provide a seat to which the dirt bag supporting ring I3 is removably clamped.

In the present disclosure, this bag ring i3 is incorporated in the muffler assembly, but considered merely as an attaching 'fitting for the mouth portion of the bag I2, it hasthe general iormof a ring which fits flush against the in Figure 3. The mouth'of the bag I2 is secured around the ring l3 in any suitable manner as for instance, by means of a metal clamping ring 15 inserted in the mouth of the bag and seating on a shoulder on the outer face of the ring.

Referring again to the discharge outlet passage I I, the same leads rearwardly from the fan,

chamber in a direction slightly oblique to the longitudinal axis of the cleaner body, so that the dust-laden air leaves the fan chamber in a path generally tangential to the periphery of the fan. Immediately beyond the portin the fan chamber defined by the entrance to the exhaust passage, the latter undergoes an abrupt increase in its horizontal and vertical cross-sectional dimensions as indicatedbythe rearwardly 'facing shoulders llb formed just beyond the port; Moreover, the exhaust passage H is rec- ,tangular in cross section, somewhat elongated horizontally and having a slightdivergence to- ;ward its outer end as shown in Figure 3. :fiKNow, the increase in the dimensions of the exhaust passage H beyond that otherwise necessary for handling the air discharged from the fan chamber is a matter of approximately an inch in 'eachdirection, this enlargement making possible the accommodation of a portion of the muiller which preferably formsa part of a detachable bag and'mufiler assembly now to be described in detail.

"Generally, the mufiler has the form of a tubular memberconsisting of an outer shell and an inner lining composed of a-relatively thick layer I 9 of any'suitable sound-absorbing materialsuch as spongerubber, cellulose padding or like material. 7

In the mufller arrangement disclosed, a sectional construction has been adopted so as to introduce a certain degree of flexibility-intermediate its end portions and for the reasons already mentioned. Thus, as clearly shown in Figure 1, the mufller proper is madeup. of an internal section l6 extending forwardly from the bag supporting ring 13 and into the enlarged exhaust passage I l. Rearwardly beyond the internal section is a flexible bellows-like section I! extending a short distance beyond the supporting-ring I3 and flnally,-there is an external section I8 which projects into the lower end portionof thedirt bag I2 and is inclined slightly in an upward direction following generally the inclination of the bag itself. -01 Referring now to some of the details of construction of themufller, the internal section 16 which fits into the enlarged exhaust passage H, includes the outer metallic shell" Ilia enclosing its portion of thesound-absorbing member l9 and suitably fastened to the supporting ring 13. In'additionto the enclosing metallic shell .I'Ea, the internal section lfi'is preferably provided'with "a" perforated. sheet metal inner liner 20 as apro'tectorfor the soft sound-absorbing material against the severe abrasive effect of the dirt particles and other objects discharged from the fan chamber. vIn fact, along one side of the exhaust passage, as shown in Figure 3, it may be desirable to omit the sound-absorbing lining entirely, because of the likelihood of pins and other pointed objects being driven against the sub face with such force as to penetrate the perforations and become firmly embedded in the soundabsorbing material. However, the treatment of the sound-absorbing surface throughout the exhaust passage is a matter of choice, although it can be stated that the use of a perforated sheet metal liner does not reduce-the effectiveness of the sound-absorbing layer materially.

In any case, the internal section I6 extends through the supporting ring l3 where it joins the short angular flexible section l1 which preferably consists of a bellows constructed of a suitable fiexible sheet material, so that it can flex readily through a limited angle in the movement of the outer section l8.

The outermost section I8 is essentially a continuation of the intermediate flexible section I! and includes the greater length of the soundabsorbing material, but preferably omits the perforated metal lining, it being assumed that the material is capableof withstanding the abrasive effect of the dirt. particles throughout this portion of the mufllen ,In any. case,fthe outer section is of rigid,v constructionlby reason of its enclosing metal shell, [8a which houses and supports the sound-absorbing material l9. And finally, it is preferred to'increase slightly the diameter of the air passage throughout the flexible and outer muiller sections I1 and [8; so as to reduce any tendency forthe creation of a back-pressure by. reason of any restrictive effeet on the mufller.

Owing to the weight. of the extended .outer muiiler section [8, it is further desirable to support it upon the ring l3 by means of a suitable hinged connection as at 2|, just above the flexible section II. The hinge may be of any simple construction, as a pin, joining the ends -of short arms projecting toward each other from the upper edges of the ring l3. and the corresponding point of a ring-like. fram member lBb at the base of the outer shell I811. forming the body of the outer muiiler section [8. A torsion spring 22 is incorporated in the hinge and acts 1 to support the weight of the flexibly supported muffler section 18.

A possible modification or alternative muffier and dirt bag arrangement is disclosedin Fig-v ure 4 wherein a principal change is the mounting of the: lower end of the bag 23 around the base of the outermost section 24' of the mufller, rather than upon the bag-supporting-ring I3, as is the case in Figure 1. In other words, the dirt bag 23 is now supported upon the hinged portion of the mufllerand therefore swings with it rather than being fixed tothe cleaner casing. This provides for a somewhat more flexible construction, but at the sametime-exposes the intermediate flexible portion of the mufller, as well as the hinged connection between the outer muffler section 24 and the supporting ring'25. Ring 25 is similar to the supporting ring l3-shown in Figure 1, exceptthat the seat-for the bag mouth is omitted, this having been-transferred to the annular base 24a of the-hinged muilier section which is now formed with- "an'annular channel about which the bag mouth is? clamped through the medium of the same type of clamp ing ring 23a as used in'the previous arrangement. A second principal change comprises the provision of a continuous sound-absorbing lining 19 which extends the entire length of the muffler assembly including the bellows-like central part instead of merelywithin the inner and outer sections as in theflrst'embodiment;

With thebag supported upon' the hinged portion of the 'mufiler, it' may be necessar'y'toprovide a more substantial hinged connection at B -and to use a'stro'nger torsion spring at the hinge. This is a; detail-which can be readily taken care of in thedesign of the mufiler mounting. As' the sound-absorbing liner 19 extends the entire length of the muffler it must be capable of flexure between v the inner and outer sections at the bellows 21. With the flexible portionof themufller exposed toview and also to' a greater degree of wear, it is preferable to enclose the flexible sectiono'f the sound-absorbing material within a short bellows member 2'! formed of some suitable sheet material, into which the sound-absorbing material is pressed or molded, but otherwise maintaining its continuity throughout the full length of the muffler. In other respects the bag and muiller are assembled and removably attached to the outlet connection from the cleaner, in the same manner as hereinbefore described.

From the foregoing description, the advantages of the mufiler arrangements hereinbefore mentioned will be readily appreciated. first place, the over-all length of the muffler has not been sacrificed although the efiect of decreased length has been attained by inserting a portion of its length into the body of the cleaner and throughout the exhaust passage which ordinarily is not treated for noise reduction. Another advantage is the practical application of a mufller to a cleaner of the type in which the handle swings relatively to the cleaner body and supports the outer end of the bag, thus introduc- 1 lug considerable flexing at the mouth portion of the bag and otherwise making it quite impractical to use a muffler of any considerable length.

And finally, with the mufiier forming an integral part of the bag assembly, it is possible to make renewals and replacements quite easily, inasmuch as the muffler is removable from the cleaner as a unit and hence readily accessible. In fact, this arrangement lends itself to the use of a muffler unit capable of being assembled as a part of the bag mounting. either for ready replacement in case of wear, or, in the event that it is deemed desirable to provide muiliers as v optional equipment, to be attached or not as the user desires.

Thus, without limiting the invention to the specific features of construction herein disclosed, I claim:

1. In a suction cleaner, the combination with suction-creating means including a fan chamher having a passage leading to the exhaust outlet therefrom, of a muffler comprising a tubular member of sound-absorbing material and adapted to be attached at said exhaust outlet with a portion of its length extending into said hassage to form a sound-reducing lining therefor.

2. In a suction cleaner, the combination with suctiomcreating means including a fan chamber having an exhaust passage of substantially increased transverse dimensions leading to a flanged outlet, of a muffler comprising a relatively thick tubular body of sound-absorbing material adapted to be attached to said flanged outlet with a portion of its length extending through out the length of said exhaust passage and forming a conduit for the air discharged from said fan chamber.

3. In a suction cleaner, the'combination with suction-creating means including a fan chamber In the having an exhaustpassage of sub'stantiallyincreased transversedimension leading to a flanged outlet, of a mufiler comprising a tubular body of I sound-absorbing material adapted to be attached haust passage and another portion extending from and beyond said exhaust passage.

5. Ina suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage, a dirt bag adapted to be attached to the outlet from said exhaust passage, and a mufller comprising a tubular member of sound-absorbing material divided into sections, one section being adapted to fit within and form a lining for said exhaust passage and the other section projecting beyond the outlet from said exhaust passage and into said dirt bag.

6. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage, a dirt bag adapted to be attached to the outlet from said exhaust passage, and a mufiler comprising a tubular member with walls of sound-absorbing material having a portion extending throughout the length of said exhaust passage and a portion projecting beyond said outlet and into said dirt bag, and means for attaching said muffler at said outlet.

'7. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage and a flanged outlet connection, and a muffler comprisin a tubular member having a lining of sound-absorbing material and divided into flexibly connected sections,

one section being adapted to fit within said exhaust passage with the other section projecting from and beyond said outlet, and a fitting carried by said muliler for detachably connecting the same to said outlet connection.

8. In a suction cleaner, the combination of suction-creating means including a fan chamber having an exhaust passage substantially enlarged diametrically and a flanged outlet connection, a d rt bag adapted for detachable connection at said outlet connection, and a mufller comprising a pair of flexibly connected sections consisting of substantially rigid tubular members lined with suitable sound-absorbin material, one of said sections being adapted to fit within the enlarged exhaust passage to form a sound-absorbing lining therefor and the other section projecting beyond said outlet connection and into said dirt bag, and an attaching fitting intermediate the flexibly connected sections of said muflller for connecting the same to said flanged outlet connection.

9. In a suction cleaner of the type havin an ambulatory body including air-moving means, and dust bag; an articulated sound-absorbing muffler comprising longitudinally spaced sections each consisting of a rigid metallic casing lined with sound-absorbing material and means pivotally interconnecting said sections and including rigid hinge means and a flexible bellowslike conduit, one of said section being fixedly carried directly by said body and forming a part of the exhaust outlet of said air-moving means and the other extending movably therefrom, said 'bag enclosing-said last mentioned section and said bellows-like conduit.

10. In a suction cleaner of the type having an ambulatory body including air-moving means, and a dust bag; an articulated sound-absorbing mufiier comprisin longitudinally spaced sections each consisting of a rigid metallic casing lined with sound-absorbing material and means pivotally interconnecting said sections and including rigid hinge means and a flexible bellows-like conduit, one of said sections being fixedly carried directly by said body and forming a part of the exhaust outlet of said air-moving means and the other extending movably therefrom, said bag enclosing and being movable with said last men tioned section.

11. In a suction cleaner of the type having an ambulatory body including air-moving means, and a dust bag; an articulated sound-absorbing muiiler comprising longitudinally spaced sections each consisting of a rigid metallic casing, means pivotally connecting said sections and including rigid hing means and a flexible bellows-like conduit, a sound-absorbing lining extending the full length of said muiiier including said bellows-like conduit, characterized in that one of said sections is carried directly by said body and forms a part of the exhaust outlet of said air-moving means and in that the other section is enclosed by said bag which is movable therewith.

MAURICE D. STAHL.

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