US3054131A

US3054131A - Vacuum cleaner head

Info

Publication number: US3054131A
Application number: US776130A
Authority: US
Inventors: Martin V Groves
Original assignee: PUL VAC Inc
Current assignee: PUL VAC Inc
Priority date: 1958-11-24
Filing date: 1958-11-24
Publication date: 1962-09-18
Anticipated expiration: 1979-09-18

Description

Sept. 18, 1962 M. v. GROVES 3,054,131 VACUUM CLEANER HEAD Filed Nov. 24, 1958 3 Sheets-Sheet 1 as 62 67 m 39 INVENTOR. L 26 F162 MARTIN v. GROVES BY ,M,@M Mal.-

ATTORNEYS Sept. 1962 M. v. GROVES 3,054,131

VACUUM CLEANER HEAD Filed Nov. 24, 1958 s Sheets-Sheet 2 GI s7 s2 as s7 59 6| s3 24 I01 I 5 9 FIG.4

INVENTOR.

MARTIN V. GROVES ATTORNEYS Sept. 18, 1962 M. v. GROVES 3,054,131

VACUUM CLEANER HEAD Filed NOV. 24, 1958 3 Sheets-Sheet 3 INVENTOR.

. MARTIN v. GROVES ATTORNEYS Patented Sept. 18, 1962 3,054,131 VACUUM CLEANER HEAD Martin V. Groves, Greenwood Lake, N.Y., assignor to gul-lyac, Inc., New York, N.Y., a corporation of New Filed Nov. 24, 1958, Ser. No. 776,130 15 Claims. (Cl. 15-382) This invention relates to vacuum cleaner heads. Certain features of the invention are useful in suction impulse devices generally.

In the use of suction cleaning devices such as vacuum cleaners, it is well known that impulse suction, in which the suction is periodically interrupted, is more effective in loosening and removing dirt from upholstery, carpets and the like than is steady, uninterrupted suction. it is an object of this invention to provide a suction impulse device for use with vacuum cleaners or the like.

It is another object of the invention to provide a vacuum cleaner head employing suction impulse for periodically interrupting the suction in the head and thereby increasing the cleaning ability of the vacuum cleaner.

Another object of the invention is to provide a vacuum cleaner head having a beater actuated by said suction impulse periodically during the intervals of interrupted suction.

One aspect of the invention contemplates a suction impulse device comprising a suction conduit having an inlet mouth and an inertia valve head movably positioned within said conduit. A first spring is provided for driving the valve head in an outward direction toward the inlet mouth and suction actuated means is provided for exerting a force in a direction opposite the force exerted on the valve head by the first spring. This suction actuated means includes an unloading valve comprising a sleeve having a valve seat at one end thereof for engagement with the valve head. A second spring or lesser driving force than the first spring is provided for driving said sleeve toward the inlet mouth. Preferably a beater is reciprocally mounted in the inlet mouth, spring biased in an inward direction and movable in an outward direction by said valve head.

According to one embodiment of the invention, a suction impulse device is provided which includes a suction conduit, a sleeve slidably mounted in said conduit for upstream and downstream movement therein with respect to the flow of air through said conduit, resilient means for urging said sleeve upstream, a valve member movably positioned in said conduit for engaging and closing the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve member, means for limiting the upstream movement of said valve member, and a second resilient means for urging said valve member upstream.

Various further and more specific objects, features and advantages of this invention will appear from the description taken in connection with the accompanying drawings which form a part of this specification and illustrate by way of example one embodiment of the invention. The invention consists in such novel features and combinations of parts as may be shown and described in connection with the apparatus herein disclosed.

In the drawings:

FIG. 1 is a bottom plan view of a vacuum cleaner head embodying the invention;

FIG. 2 is a longitudinal sectional view taken along line 22 of FIG. 1 showing the valve head and sleeve during their downstream movement;

FIG. 2A is an enlarged partial view showing the junction of the supporting arms and the valve spindle of FIG. 2 more clearly;

FIG. 3 is a partial longitudinal sectional view similar to FIG. 2 showing the valve head and sleeve near the beginning of their upstream movement;

FIG. 4 is a view similar to FIG. 3 showing the valve head and sleeve at a further stage of their upstream movement;

FIG. 5 is a view similar to FIG. 2 showing certain of the interior parts of the vacuum cleaner head of FIGS. 14 more clearly;

FIG. 6 is a plan view partly in section showing further details of parts shown in FIG. 5;

FIG. 7 is a top plan view partly in section, showing spring clip and supporting ring for holding the beater in position in the Vacuum cleaner head shown in (FIGS. 1, 2, 3, 4 and 11;

FIG. 8 is a longitudinal sectional view taken along line 88 of FIG. 7;

FIG. 9 is a cross-sectional view taken along line 99 of FIG. 8;

FIG. 10 is a view showing the beater detached from the vacuum cleaner head shown in FIGS. 1-4;

FIG. 11 is a view similar to FIG. 2 showing the housing of the vacuum cleaner head adapted to be used as a conventional head; and

FIG. 12 is an enlarged view of a portion of the apparatus shown in FIG. 5.

Referring more particularly to FIGS. l and 2, a suction impulse device is shown taking the form of a vacuum cleaner head designated in its entirety as 21 having a housing 22 which (see also FIG. 11) includes a lower housing 22a and an upper housing 22b and forms a suction conduit for the passage of air through the vacuum cleaner head 21. As best shownin FIG. 1, the lower housing 22a is hollow and includes an elongated inlet opening 23 in which an agitating member shown in the drawings as a beater 24 is removably positioned as'described below. The portion of the lower housing 22a surrounding the elongated inlet opening 23 is preferably provided throughout all or part of its length with transverse grooves 25 for facilitating entry of air into the house ing when the inlet opening is pressed against the surface being cleaned. A longitudinally extending depression or groove 23a may also be provided in the portion of the housing surrounding the inlet opening 23 for the same purpose. The elongated lower part of the lower housing 22a containing the inlet opening 23 is preferably provided with a circumferential resilient member such as a rubber grommet 26 in order to protect furniture or other objects from direct accidental contact with the elongated portion of the lower housing.

The upper housing 22b, like the lower housing 2212, may be constructed of any suitable material, but in the present embodiment the lower housing 22a is an aluminum die casting and the upper housing 22b is made of light gauge steel. The upper housing 2% includes a tubular neck 27 which for convenience is separately formed and rigidly secured to the body of 22b as by welding at 28. It should also be understood that the housing 22, rather than being formed of upper and lower portions, may be formed integrally. The form shown in the drawings, in which the housing is made up of upper and lower portions, is preferred since this facilitates re moval of interior components as described below so that the same housing may, if desired, be used in a conventional manner without the suction impulse features of this invention.

The upper housing 221) may be connected to the lower housing 22a in any suitable manner. In the present embodiment (FIGS. 2 and 3) the lower housing 22a is secured to the upper housing 22b by the use of

spring clips

36 and 37. The clip 36 is secured to the lower housing 22.; by a rivet 38 while the clip 37 is pivotally secured tothe lower housing 22a by a pin 39 and serves as a releasable r 3 latch. The

clips

36 and 37 have

upper portions

40 and 41 shaped to engage an outwardly projecting flange 42 of the upper housing 22b and the latch 37 is provided with a handle 43 to facilitate separation of the housing parts 22a and 22b. p

The extending tubular portion 27 (FIG. 2) serves to provide a suitable connection for connecting the vacuum cleaner head 21 to a hose nozzle 31 or other conduit leading to the vacuum cleaner tank. Suitable means such as a spring catch 29 having a detent pin 30 is provided for releasably securing the vacuum cleaner head 21 to the nozzle31. The nozzle 31 is preferably of suitable size to fit tightly over the projecting portion 27. Leakage of air through the connection thus formed between the nozzle 31 and the projecting portion 27 of the vacuum cleaner head housing may be substantially prevented by the use of a sealing sleeve 32 formed of rubber or other suitable material.

Referring to 'FIGS. 2 and 3, a sleeve 51 is positioned within the housing 22 with its upper or downstream end (with respect to the flow of air through the suction conduit formed by the housing 22) snugly but slidably engaged in a reduced diameter 52 of the upper housing 22b abutting a shoulder which is conveniently formed by the upstream end of the extending tubular portion 27 of the upper housing 22b. A centrally located spindel 53 (see FIG. 2A) extends upstream from the sleeve 51 and is fixedly secured in position with respect thereto by relatively narrow supporting arms such as 54 (FIGS. and 6) which comprise conical segments for-med integral with the sleeve 51 so as to allow free passage of air there through. The supporting arms 54 are provided at their upstream ends with a ring 55 to which the upper or downstream end of the spindle 53 is rigidly secured as by riveting. A helical compression spring 56 surrounds the spindle 53 with its downstream end abutting the ring 55. Turned over portions 57 of the ring 55 serve to hold the spring 56 in position on the spindle 53.

An unloading valve comprising a sleeve 61 (FIGS. 2 and 3) is slidably mounted within the housing 22 for upstream and downstream movement therein. The sleeve 61 may be mounted in any suitable manner, but should be so mounted as to prevent any substantial passage of air betwen the exterior of the sleeve and the interior of the housing. As shown in FIGS. 2-5, movement of air through the interior of the housing 22 past the exterior of the sleeve 61 is prevented by the use of flexible airtight sealing means such as a sleeve bellows 62 which is fastened in airtight relationship about the outer periphery of the sleeve 61 and is also securely fastened in airtight relationship to the interior of the housing 22. The airtight relationship between the bellows and the housing may conveniently be achieved by allowing an extending beaded flange 63 of the bellows 62 to extend under the portion 42 of the upper housing 221) where it may be securely clamped by the action of the

springs

36 and 37 as described above, the flange 63 of the bellows 62 providing the necessary resiliency for airtight sealing between the upper and lower portions of the housing 22. The airtight relationship between the bellows and the lower or upstream end of the sleeve 61 is preferably provided by engaging a beaded end 65 of the bellows 62 in a peripheral groove formed in a rolled over lip 64 which also serves as a valve seat for engagement with a valve head to be described below.

The flexible bellows 62 may be formed of any suitable material but thin rubber or the like is preferred for its ability to withstand constant flexing when the apparatus is in use as described below. Use of a flexible bellows such as 62 to provide an airtight seal between the interior of the housing 22 of the vacuum cleaner head 21 and the exterior of the sleeve 61 is preferred since this allows the sleeve 61 to move freely within the housing 22 without the necessity of maintaining extremely close tolerances in manufacturing the housing or the sleeve. It is, of course,

housing. is free to move only in response to flexing of the spring Within the scope of the invention to lit the sleeve within the housing with sufliciently small clearance so that the desired airtight relationship may be obtained without the use of the bellows or the airtight relationship may be obtained in any other suitable manner.

The valve seat 64 of the sleeve 61 preferably also forms an interior shoulder 66 near the upstream end of the sleeve serving as a seat for one end of a helical compression spring 67 disposed within the sleeve 61 surrounding the spring 56 and whose other end extends downstream and surrounds the sleeve 51 in abutting engagement with a lock nut 68 by which the compression of the spring may be varied to alter the operation of the apparatus as described below.

A poppet valve member shown in the drawings as an inertia valve head 71 is provided with an annular recess 72 within which is engaged the free end of the spring 56 to thereby operatively support the head 71 whose downstream end has a portion 73 adapted to cooperatively engage the valve seat portion 64 of the sleeve 61.

From FIG. 2 it can be seen that when the portion 73 of the valve head 71 is in tight engagement with the valve seat portion 64 of the sleeve 61, movement of air through the vacuum cleaner head 21 is completely prevented. The valve head 71 may be of any suitable material, preferably a resilient material such as rubber in order to insure airtight sealing engagement with the valve seat 64.

As mentioned above, a beater 24 may be resiliently mounted in the upstream portion of the lower housing 22;: of the vacuum cleaner head 21 adjacent the inlet opening 23. The beater 24 is resiliently mounted in any suitable manner such as by a spring 76 connecting the beater to the interior of the lower housing 22a. As best shown in FIG. 1, the beater 24 maybe provided on its outer end with grooves such as 77, thereby forming protuberances such as 78 to aid in dislodging dirt when the beater strikes the carpet or other material being cleaned.

As best shown in FIGS. 7-1(), as well as FIGS. 1-4, the clip 76 comprises a band of spring steel with a bent portion 81 adapted to engage an upper portion 82 of the beater 24. The upper portion 82 of the beater is preferably narrower than the bottom portion of the beater which extends into the opening 23 and is preferably substantially the same width as the spring 76. The upper portion 82 of the beater is preferably provided with an extending ridge 83 adapted to engage a slot 84 intermediate the width of the spring 76 and extending inwardly from. the end thereof in order to prevent lateral movement of the beater with respect to the spring. The spring 76 (FIGS. 24) may be removably secured within the lower housing 22a by means of a retaining ring 89 and a spring clip 85 (FIGS. 8 and 9) which is adapted to fit tightly within a recess 86 formed in the interior wall of the lower housing. The spring clip 85 may be fastened to the spring 76 in any suitable manner such as by a rivet 87 passing through the upper portion of the spring 76 and a downwardly extending portion 88 of the retaining ring 89 which has an outwardly extending shoulder 90 (FIG. 8) adapted to fit between the extending flange 63 of the bellows 62 and a shoulder 91 of the interior of the lower housing 22a. The retaining ring 89 thus serves to restrain the spring 76 and the beater 24 against linear movement longitudinally of the housing 22 while the spring clip 85 serves to retain the spring 76 and the beater 24 against rotation within the The heater 24 is thus restrained in place and 76. In the present embodiment the spring clip 85 is shown as being integrally formed with the spring 76 but the clip may, if desired, be separately formed and secured to the upper portion of the spring 76 by the rivet 87 or the spring 76, spring clip 85 and retaining ring 89 may be integrally formed as one unit.

removed from the assembly if it is desired to operate the vacuum cleaner head 21 without the beater. This may be accomplished merely by releasing the spring clips 36 and 37, separating the upper and lower portions of the housing 22, removing the beater, spring and retaining ring and then reassembling the upper and lower portions of the housing.

It is also possible, if desired, to remove the beater 24 without removing the spring 76 or the retaining ring 89. Since the beater 24 is held in the spring 76 by friction, the beater may be removed by simply pulling it out of the vacuum cleaner head through the inlet opening 23. Likewise, the beater 24 may be inserted into the portion 81 of the spring 76 without removing the spring or retaining ring from the vacuum cleaner head. To guard against possible damage to the spring 76 due to its being deformed when pushing the beater 24 into the portion 81 of the spring 76, an inward projection 92 (FIGS. 2-4) is provided on the interior of the lower housing 22a to provide solid support for the spring 76 during the insertion of the beater 24.

It can be seen from the drawings and the above description, that since the

springs

56 and 67 are both under compression, the spring 56 is adapted to drive the valve head 71 towards the inlet mouth 23 while the spring 67 is adapted to drive the unloading valve comprising the sleeve 61 toward the inlet mouth. The normal tendency of the apparatus is, therefore, to urge the valve head 71 and the valve seat 64- in an upstream direction until the valve head is stopped by the portion of the spring 76 surrounding the upper portion 82 of the beater 24. The resiliency of the spring 76 is such that the beater 24- may be pushed in an upstream direction until the protuberances 78 on its upstream end come into firm contact with the surface being cleaned but at the same time the spring 76 is preferably sufiiciently stiff so that the portion 81 of the spring 76 which covers the upper portion of the beater does not come into contact with the interior of the lower housing 22a. As best seen from FIG. 2, when the valve head 71 and valve seat 64 are both positioned as far upstream as the construction of the apparatus allows, no air can pass through the suction conduit formed by the interior of the vacuum cleaner head 21 since the seal formed between the valve head and the valve seat cooperates with the bellows 62 to prevent passage of air either inside or outside the sleeve 61.

When the source of vacuum, such as a conventional vacuum cleaner attached to the vacuum cleaner head 21 by the nozzle 31 as described above, is activated, the resulting suction produced in the interior of the sleeve 61 by the suction actuated means including the vacuum cleaner is sufficiently strong to pull the valve head 71 and the sleeve 61 downstream against the action of the springs 56 and 67'. The spring 56 is designed so as to exert a greater force when compressed than that exerted by the spring 67 and the relative compressions of the two springs are such that downstream movement of the valve head ceases while the suction force within the sleeve 61 is still sufiicient to move the sleeve 61 slightly further downstream against the urging of the spring 67. Alternatively, the

springs may be designed so that downstream movement of the valve head is stopped when the valve head comes into contact with the end of the spindle 53 as shown in FIG. 3. This additional downstream movement of the sleeve 61 results in movement of the valve seat 64 away from the portion 73 of the valve head 71 and thereby opens an annular valve slot 101 to the passage of air as indicated in FIGS. 3 and 4. The rush of air through the thus opened valve slot substantially equalizes the pressure on the upstream and downstream sides of the valve head 71 and effectively destroys the suction effect holding the valve head 71 and the sleeve 61 downstream against the urging of the

springs

56 and 67. The

springs

56 and 67 drive the head 71 and sleeve 61 upstream to the position shown in FIG. 2.

Since the spring '56 is under substantially greater compression than the spring 67, the valve head 7'1 moves upstream at a faster rate than the sleeve 61 thereby widening the valve slot 101 as the valve head and sleeve move upstream. This allows ample room for passage of air and dirt between the valve head 71 and the valve seat 64 as these components move upstream. Air, as well as dirt which is sucked in through the opening 23, passes through the valve slot 101 and the housing 22 to a conventional collecting bag or filter attached thereto as by a length of hose and nozzle 31 as described above.

When the valve head 71 engages the spring 76, as best shown in FIG. 4, it has considerable momentum and this momentum is suiiicient to force the beater 24 upstream against the action of the spring 76 until the protuberances 78 on the end of the beater come in sharp contact with the rug or fabric, etc. being cleaned thereby serving to dislodge embedded dirt. In the event the vacuum cleaner head 21 is not pressed firmly against the surface being cleaned, the spring 76 will prevent excessive upstream movement of the beater as described above.

Once the valve head 71 has completed its upstream movement, the spring 56 holds it in the extreme upstream position until the sleeve 61, under the urging of the spring 67, reaches its most extreme upstream position at which time the valve seat 64 engages the surface 73 of the valve head as shown in FIG. 2 and the entire cycle is repeated.

It will be appreciated that the width of the slot 101 formed between the valve head and the valve seat during the upstream movement of these members will depend largely upon the relative effective strengths of the springs 56 and 67'. Some control may, therefore, be exercised over the width of this slot as Well as the frequency of operation of the beater by adjusting the degree of compression under which one or both of these springs is held and thereby adjusting the effective strength of one or both of the springs. This may be accomplished in any suitable manner, such as by the use of the adjustable nut 68 to restrain the upper end of the spring 67.

As best shown in FIGS. 5, 6 and 12, the nut 68 is provided with double lead threads 69 which engage threads 1162 on the sleeve 51. The elfective strength of the spring 67 may be adjusted by turning the nut 68 so as to move it longitudinally on the sleeve 51. A longitudinal groove or slot 74 is provided in the threads 102 of the sleeve 51. As best shown in FIG. 12, a detent 69a is provided on the threads 62 as by deforming a portion of thread as shown. In the position shown in FIG. 12 the detent 69a is in the slot 74. Due to the action of the spring 67, the nut 68 is forced into the position shown in FIG. 12 with its threads 69 closely abutting the threads 102 ofthe sleeve 51 and with the detent 69a occupying a position in the slot 74 corresponding to an interrupted portion of the thread 102. While the nut 68 is held in this longitudinal position by the spring 67, it cannot be turned because of the position of the detent 69a which would engage the portion of the threads 102 at the edge of the slot '74 and thereby prevent the nut from being turned. This arrangement insures against accidental turning of the nut such as by vibration.

To turn the nut 68 and thereby adjust the effective strength of the spring 67 it is necessary only to move the nut longitudinally against the urging of the spring 67 until the detent 69a is clear of the threads 102. The spaces 70 between the double lead threads allow ample space for this limited longitudinal movement of the nut relative to the sleeve. Once the nut has been moved slightly in this manner, it may be turned to adjust the spring. In turning the nut, the spring 67 constantly urges the detent 69a against the threads 102 and, unless the force of the spring is counteracted, will force the nut back into the locked position shown in FIG. 12 when the detent reaches the slot 74. By thus varying the effective strength of the spring 67, the relative upstream speeds of the valve head 71 and the sleeve 61 may be varied and this in turn will allow varying widths of slots such as 101 to form during such upstream movement.

It is, as described above, entirely feasible to operate the apparatus without the beater 24 and spring 7 6 and in this event the downstream movement of the valve head 71 may be limited either by the construction of the spring 56 or by impact of the valve head 71 against the lower portion of the interior of the lower housing 22a.

In the event it is desired to operate the vacuum cleaner head 21 as a conventional head without the suction impulse features described above, these interior components may be removed by separating the upper and lower housings 22a and 22b as described above and removing the suction impulse components. FIG. 11 shows the vacuum cleaner head 21 with the suction impulse components and beater removed. As shown in FIG. 11, a sealing ring 44- of suitable material such as rubber may be inserted between the upper and lower housings to insure airtight engagement between the same when the vacuum cleaner head is used in a conventional manner.

While the invention has been described in detail with respect to certain preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended to cover all such changes and modifications in the appended claims.

What I claim is:

1. A suction impulse device comprising a suction conduit having an inlet month, an inertia valve head movably positioned in said conduit, a first spring disposed in said conduit for driving said valve head toward said inlet mouth, a heater resliently positioned on the upstream side of and in the path of movement of said valve head, suction actuated means moveable in a direction opposite to the direction of the force exerted on said valve head by said first spring, said suction actuated means including an unloading valve comprising a sleeve moveable relative to said beater and having a valve seat at one end thereof for engagement with said valve head, and a second spring disposed in said suction conduit of lesser driving force than said first spring for driving said sleeve toward said inlet mouth and against said valve head to close said conduit.

2. A suction impulse device comprising; a suction eonduit having an inlet mouth, a valve including an inertia valve head movably positioned in said conduit, an unloading valve member comprising a sleeve positioned in said conduit downstream of said valve head and formed with valve seat means at one end thereof for engagement with said valve head, a first spring urging said inertia valve head towards said inlet mouth, and a second spring of lesser driving force than said first spring and urging said sleeve towards said valve head normally to maintain said valve head in engagement with said valve seat means on said sleeve and thus said valve normally closed, said sleeve being movable against the force of said second spring to open said valve and permit the flow of air from said inlet mouth to said conduit upon the application of a suction in said conduit downstream of said valve.

3. A suction impulse device comprising; a suction conduit having an inlet mouth, a valve including an inertia valve head movably positioned in said conduit, an unloading valve member comprising a sleeve positioned in said conduit downstream of said valve head and formed with valve seat means at one end thereof for engagement with said valve head, a first spring telescopically disposed relatively to said sleeve and urging said inertia valve head towards said inlet mouth, and a second spring of lesser driving force than said first spring surrounding said first spring and urging said sleeve towards said valve head normally to maintain said valve head in engagement with said valve seat means on said sleeve and thus said valve normally closed, said sleeve being movable against the force of said second spring to open said valve and permit 8 the flow of air from said inlet mouth to said conduit upon the application of a suction in said conduit downstream of said valve.

4. A suction impulse device comprising a suction conduit having an inlet mouth, an inertia valve head movably positioned in said conduit, a first spring for driving said valve head toward said inlet mouth, a beater resiliently positioned on the upstream side of and in the path of movement of said valve head for striking a surface in contact with said inlet opening in response to the force exerted on said heater by said valve head, suction actuated means moveable in a direction opposite to the direction of the force exerted on said valve head by said first spring, said suction actuated means including an unloading valve comprising a sleeve having a valve seat at one end thereof for engagement with said valve head, and a second spring of lesser driving force than said first spring for driving said sleeve toward said inlet mouth and said valve head to close said conduit.

5. In a suction impulse device having an inlet mouth at an upstream end and an outlet opening at a downstream end, the combination of a suction conduit in direct communication at one end with said inlet mouth and at the other end with said outlet opening, said conduit constituting the sole passage for the flow of air between the upstream and downstream ends of said device, a sleeve slidably mounted in said conduit for upstream and downstream movement therein with respect to the flow of air through said conduit, resilient means for urging said sleeve upstream a valve member movably positioned in said conduit for engaging and closing the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve member, means for limiting the upstream and downstream movement of said valve member and a second resilient means for urging said valve member upstream.

6. In a suction impulse device having an inlet mouth at an upstream end and an outlet opening at a downstream end, the combination of a suction conduit in direct communication at one end with said inlet mouth and at the other end with said outlet opening, said conduit constituting the sole passage for the flow of air between the upstream and downstream ends of said device, a sleeve mounted in said conduit for upstream and downstream movement therein with respect to the flow of air through said conduit, resilient means for urging said sleeve upstream, valve means movably positioned in said conduit for closing the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve means, and a second resilient means for urging said valve means upstream.

7. in a vacuum cleaner, the combination comprising a suction conduit; a sleeve slidably mounted in said conduit for upstream and downstream movement therein with respect to the flow of air through said conduit; said sleeve providing a valve seat on its upstream end a spring for urging said sleeve upstream; means providing an air seal between the exterior of said sleeve and the interior of said conduit to prevent passage of air therebetween; a valve head movably positioned in said conduit and adapted to close the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve head thereby sealing off the flow of air through said sleeve; a second spring for urging said valve head upstream, said second spring being stronger than said first spring whereby during upstream movement of the sleeve and valve head the sleeve moves more slowly than the valve head thereby opening a progressively wider valve slot between said valve seat and said valve head; and means for limiting the upstream and downstream movement of said valve head.

8. In a vacuum cleaner, the combination comprising a suction conduit; a sleeve slidably mounted in said conduit for upstream and downstream movement therein a .ni

with respect to the flow of air through said conduit, the upstream end of said sleeve forming a valve seat; a spring for urging said sleeve upstream; an elongated inlet mouth communicating with the upstream end of said conduit; means providing an air seal between the exterior of said sleeve and the interior of said conduit to prevent passage of air therebetween; an inertia valve head movably positioned in said conduit and adapted to engage said valve seat to close the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve head thereby sealing off the flow of air through said sleeve and a second spring for urging said valve head upstream, said second spring being stronger than said first spring whereby during upstream movement of the sleeve and valve head, the sleeve moves more slowly than the valve head thereby opening a progressively wider valve slot between said valve seat and said valve head; means for limiting upstream movement of said valve head; and adjustable means for limiting downstream movement of the valve head.

9. In a vacuum cleaner, the combination comprising a suction conduit; a sleeve slidably mounted in said conduit for upstream and downstream movement therein with respect to the flow of air through said conduit, the upstream end of said sleeve forming a valve seat; a spring for urging said sleeve upstream; an elongated inlet mouth communicating with the upstream end of said conduit; flexible airtight means interposed between the exterior of said sleeve with the interior of said conduit to prevent passage of air therebetween; an inertia valve head movably positioned in said conduit and adapted to engage said valve seat to close the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve head thereby sealing off the flow of air through said sleeve; a second spring for urging said valve head upstream, said second spring being stronger than said first spring whereby during upstream movement of the sleeve and valve head, the sleeve moves more slowly than the valve head thereby opening a progressively wider valve slot between said valve seat and said valve head; adjustable means for limiting downstream movement of the valve head; and a heater resiliently positioned in said inlet mouth for beating material in contact with said inlet mouth in response to upstream movement of said inertia valve head.

10. A suction impulse device comprising a conduit, means for producing a suction in said conduit, an inlet mouth at the upstream end of said conduit, a sleeve hav ing a valve seat and being movable in said conduit, in a downstream direction under the influence of the suction in said conduit, a valve member normally disposed upon said valve seat and movable in a downstream direction with said sleeve under the influence of said suction, means limiting the downstream movement of said valve member relatively to said sleeve thus to unseat said valve member, a spring urging said valve member upstream of said sleeve, a second spring effective to move said sleeve upstream towards said valve member when said valve member is unseated, and a beater resiliently positioned in said inlet mouth for intercepting the upstream movement of said valve member thus effectively limiting said movement and utilizing the impact forces delivered thereby to beat material in contact with said inlet mouth.

11. A suction impulse device comprising a suction head including an upper housing and a lower housing detacha=bly secured together and providing a suction conduit, a unitary suction impulse assembly removably disposed in said suction head, said assembly comprising a valve including an inertia valve head, an unloading valve member comprising a sleeve disposed downstream of said valve head when said assembly is disposed in said suction head, said sleeve being formed with valve seat means at the upstream end thereof for engagement with said valve head, a first spring urging said inertia valve head towards said inlet mouth, and a second spring of lesser driving force than said first spring and urging said sleeve towards said valve head normally to maintain said valve head in engagement with said valve seat means on said sleeve and thus said valve normally closed, said sleeve being movable against the force of said second spring to open said valve and permit the flow of air from the inlet mouth of said conduit upon the application of a suction in said conduit downstream of said assembly.

12. A suction impulse device comprising a suction head including an upper housing and a lower housing detachably secured together and providing a suction conduit, a unitary suction impulse assembly removably disposed in the upper housing of said suction head, said assembly comprising a valve sleeve having a valve seat on its upstream end, a first spring urging said sleeve upstream, a valve head, a second spring urging said head upstream with a greater force than that exerted by said first spring, means responsive to suction in said head for moving said sleeve and valve head downstream against the action of said springs, a beater disposed in said conduit for intercepting the upstream movement of said valve head and utilizing the impact forces delivered thereby to beat material in contact with said housing, said valve sleeve being movable relatively to said beater, and a stop in said suction head for arresting downstream movement of said valve head to hold the same spaced upstream of said valve seat when said sleeve reaches the limit of its downstream movement.

13. In a vacuum cleaner, the combination comprising a suction conduit; a sleeve slidably mounted in said conduit for upstream and downstream movement therein with respect to the flow of air through said conduit; a spring for urging said sleeve upstream; means providing an air seal between the exterior of said sleeve and the interior of said conduit to prevent passage of air therebetween; a valve head movably positioned in said conduit and adapted to close the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve head thereby sealing off the flow of air through said sleeve; a second spring for urging said valve head upstream, said second spring being stronger than said first spring whereby during downstream movement of the sleeve and valve head, the valve head moves more slowly than the sleeve thereby opening a progressively wider valve slot between said valve seat and said valve head; and means for limiting the upstream movement of said valve head.

14. In a vacuum cleaner, the combination comprising a suction conduit; a sleeve slidably mounted in said conduit for upstream and downstream movement therein with respect to the fiow of air through said conduit, the upstream end of said sleeve forming a valve seat; a spring for urging said sleeve upstream; an elongated inlet mouth communicating with the upstream end of said conduit; means providing an air seal between the exterior of said sleeve and the interior of said conduit to prevent passage of air therebetween; an inertia valve head movably positioned in said conduit and adapted to engage said valve seat to close the upstream end of said sleeve upon upstream movement of said sleeve into contact with said valve head thereby sealing ofi the flow of air through said sleeve and a second spring for urging said valve head upstream, said second spring being stronger than said first spring whereby during downstream movement of the sleeve and valve head, the valve head moves more slowly than the sleeve thereby opening a progressively wider valve slot between said valve seat and said valve head; and means for limiting upstream movement of said valve head.

15 A suction impulse device comprising; a suction conduit having an inlet mouth, a valve including an inertia valve head movably positioned in said conduit, an unloading valve member comprising a sleeve positioned in said conduit downstream of said valve head and formed with valve seat means at one end thereof forengagement with said valve head, a first resilient means urging said inertia valve head towards said inlet mouth, and a second resilient means of lesser driving force than said first resilient means and urging said sleevetowards said valve head normally to maintain said valve head in engagement with said valve seat means on said sleeve and thus said valve normally closed, said sleeve being movable against the force of said second resilient means to open said valve and permit the flow of air from said inlet mouth to said conduit upon the application of a suction in said conduit downstream of said valve.

, RefereucespCited in the file of this patent UNITED STATES PATENTS Lichtenberg July 30, Marshall Aug. 4, Karlstrom Feb. 16, Ott Nov. 25, Kelly Mar. 31, Ostwald Nov. 25,

FOREIGN PATENTS Great Britain Aug. 29,