US2776446A

US2776446A - Nozzle height adjustment mechanism for suction cleaners

Info

Publication number: US2776446A
Application number: US281945A
Authority: US
Inventors: George A Brace
Original assignee: Hoover Co
Current assignee: Hoover Co
Priority date: 1952-04-12
Filing date: 1952-04-12
Publication date: 1957-01-08
Anticipated expiration: 1974-01-08

Description

Jan. 8, 1957 e. A. BRAC'E 2,776,446

NOZZLE HEIGHT ADJUSTMENT MECHANISM FOR SUCTION CLEANERS Filed April 12, 1952 4 Sheets-Sheet l INVENTOR. George A. Brace ATM ATTORNEY.

Jan. 8, 1957 G. A. BRACE 2,776,446

NOZZLE HEIGHT ADJUSTMENT MECHANISM FOR SUCTION CLEANERS Filed April 12 1952 4 Sheets-Sheet 2 57 IN VEN TOR.

Geozye A. Brace BY M ATTORNEY.

Jan. 8, 1957 G. A. BRACE 2,776,446

NOZZLE HEIGHT ADJUSTMENT MECHANISM FOR SUCTION CLEANERS Filed April 12, 1952' 4 Sheets-Sheet 3 INVENTOR. Geor yeAJirace ATTORNEY.

Jan. 8, 1957 e. A. BRACE 2,776,446

NOZZLE HEIGHT ADJUSTMENT MECHANISM FOR SUCTION CLEANERS Filed April 12, 1952 4 Sheets-Sheet 4 'Dff-lhe 'f'loor" INVENTOH. Geolye A bra ce ll BYW ATTORNEY.

United States Patent NOZZLE HEIGHT ADJUSTMENT MECHANISM FOR SUCTION CLEANERS George A. Brace, Highland Park, IlL, assignor to The Hoover Company, North Canton, Ohio, a corporation My invention relates to the art of suction cleaners and more particularly to a simple, economical and reliable mechanism for adjusting the height of the cleaner nozzle relative to a supporting surface to compensate for varying thicknesses of surface coverings and to raise the nozzle to an inoperative position for converting the apparatus to off-the-floor cleaning.

Modern suction cleaning devices are called upon to clean floor coverings such as rugs differing very widely in air flow resistance, thickness and pile depth. In order to clean a rug or carpet properly with a suction cleaner, the position of the nozzle, relative to the surface of the carpet, is an important factor which requires adjustment to compensate for carpet thickness and pile depth. Within limits, adjustment of the nozzle may be accomplished automatically by proper choice of the width of the cleaner supporting wheels and the position thereof relative to each other, to the nozzle and to the point of connection of the propelling handle to the cleaner body. An arrangement of this type is disclosed and claimed in the patent to Taylor 2,267,764, issued December 30, 1941. The variation of modern surface coverings is so extreme that it has been found desirable to provide two or more ranges of adjustment of the cleaner supporting wheels relative to the body thereof within each of which the broad and narrow wheel combination of the Taylor patent insures proper action of the cleaner under all conditions. For example, the cleaner may be adjustable for thick and thin carpets or for thin, medium and thick carpets as desired. Once the relation of the wheels to the cleaner is set for any of these ranges, the cleaner will automatically adjust itself properly within the range. Due to the fact that a particular household may have rugs widely varying in characteristics, it is necessary to provide an adjustment which is simple, economical and thoroughly reliable in operation. It is also desirable in modern cleaners to support the rear wheels thereof resiliently to aid the operator in manipulating the cleaner over doorsills and also in starting the cleaner when the handle is in a nearly vertical position as frequently happens at the beginning of a forward operating stroke of the cleaner. It is also desirable to interrelate the parts in such fashion that the resilient mounting of the rear wheels does not disturb the set adjustment of the nozzle height adjusting means when the rear of the cleaner is depressed during normal operating conditions.

it is a principal object of my invention to provide a suction cleaner of the wheel supported type having the rear Wheels thereof resiliently mounted and provided with a mechanism by which the nozzle may be adjusted in response to a simple pressure on the rear of the cleaner applied to the handle or by the foot of the operator for the purpose of changing the adjustment range on the nozzle height adjusting mechanism. It is also an object of the invention to provide a cleaner having a nozzle height adjusting means of the aforementioned character so arranged that it is impossible as a practical matter to change the adjustment of the mechanism inadvertently 'ice while manipulating the cleaner over a doorsill or by unusual pressure applied to the handle for the purpose of starting a forward stroke of the cleaner or for releasing the suction drag between the nozzle and the cleaner by momentarily tilting the nozzle to a high position.

Other objects of the invention will become apparent as the description proceeds when taken in connection with the accompanying drawing wherein:

Figure 1 is a side elevational view of a suction cleaner embodying my invention, having parts broken away and sectioned to illustrate a nozzle adjusting mechanism;

Figure 2 is a partly diagrammatic View of the cleaner casing and adjusting mechanism shown in Figure l illustrating the position of the parts at the moment of change in the adjustment of the nozzle height adjusting mechanism;

Figure 3 is a view similar to Figure 2 illustrating the position of the parts in the high nozzle operating or thick carpet cleaning position;

Figure 4 is a fragmentary view partly in section illustrating a retaining arm and factory adjustment on the nozzle height adjusting mechanism;

Figure 5 is a rear view taken along the line 5-5 of Figure 1 and looking in the direction of the arrows;

Figure 6 is a view similar to Figure 1 illustrating a modified form of the invention;

Figure 7 is a view of the cleaner body and adjusting mechanism illustrating the position of the parts when the cleaner is adjusted for conversion to oif-the-fioor cleaning;

Figure 8 is a sectional view taken along the line d-ti of Figure 6 and looking in the direction of the arrows;

Figure 9 is a view similar to Figure 1 illustrating another modified form of the invention;

Figure 10 is a view of the apparatus of Figure 9 illustrating the position of the parts when adjusted for conversion to oifthe-floor cleaning; and

Figure 11 is a view taken along the line 11-11 of Figure 9 and looking in the direction of the arrows.

Referring now to the drawing, the form of the invention illustrated in Figures 1 to 5 will first be described in detail. The general arrangement of the cleaner herein illustrated is that disclosed in the patent to Berg 2,330,665, issued Sept. 28, 1943 with my novel wheel adjustment applied thereto.

My cleaner comprises a main body 1 which will house the usual suction nozzle 2 across the front thereof Within which a rotary surface cleaning and agitating device indicated at 3 is mounted. A motor hood 4 is positioned on top of the main body 1. A manipulating handle 5 is pivotally connected to the cleaner construction at the rear thereof directly over a suitable filter 6 which is detachably mounted upon an exhaust outlet port 7 at the 7 rear of the cleaner. The main body 1 is provided with a suction fan housing and exhaust duct 10 on the underside thereof similar to that disclosed in the abovementioned patent to Berg and terminating in the outlet 7. A side opening passageway 8 forms an entranceway to the fan chamber for a conversion tool to convert the cleaner for off-the-fioor operation in the manner illustrated in the aforesaid patent to Berg. The front of the cleaner is supported by broad front wheels 9 which are attached to the main body of the cleaner just rearwardly of the nozzle 2 and adjacent opposite ends thereof. The rear end of the cleaner is supported by a pair of rear wheels 12 having a narrower tread than the front wheels 9 and which are carried by pins 13 projecting from the opposite sides of a rear wheel bracket structure 14. The bracket 14 is substantially U-shaped in plan view having the bar portion 15 at the rear thereof extending between the rear wheels 12. Each side arm of the U-shaped bracket 14 is pivotally mounted upon a stud 17 carried by a boss 18 depending from the underside of the air duct 10.

One arm of the bracket 14 has a forwardly projecting extension 19 extending through a suitable slot into the passageway 3 to bar insertion of a conversion tool except under certain conditions to be described more fully hereinafter. A pair of compression springs 20 bears between the underside of the duct and the portion of the bracket 14 in order to bias the rear wheels 12 away from the cleaner body which has the effect of pivoting the cleaner body about thefront wheels 9 to lower the nozzle 2 relative to a supporting surface.

The wheel adjusting mechanism comprises a segmental adjusting cam having a rim section 26 positioned beneath a sight opening 27 in the rear portion of the body 1 outwardly of the hood 4 in order to permit the operator to observe position indicating markings applied to the rim 26 indicating the particular adjustment of the nozzle. The adjusting cam 25 is pivotally mounted on a stud 21 threaded into a boss 22 projecting from one side of the portion 10 of the main body 1. A spring washer 23 is interposed between the head of the stud 21 and the cam 25 to apply a frictional drag on the cam 25 to prevent accidental pivotal movement of the cam on the stud 21. The cam 25 has an inverted U-shaped cut out section 29 providing a pair of stops or detents 3t) and 31 on opposite sides of and below the stud 21 and a supporting arm section 32 extending upwardly from the bottom of the cam 25 to engage the stud 21 between the stops or detents and 31. Above the stud 21, the section 32 is provided with a pointed portion 33.

A tension or hook member 35, see Figures 4 and 5, is provided with an enlarged base section snugly receiving an adjusting eccentric 37 formed on a threaded mounting stud 33 which extends through the bight portion 15 of the bracket 14 and is secured thereto by a nut and spring washer 39. The end of the stud 38 is slotted, as indicated at 40, to receive a suitable adjusting tool, such as a screw driver, for rotating the same to change the position of the eccentric 3'7 with reference to the axis of the stud which raises or lowers the member to provide a factory adjustment thereon which is utilized to compensate for manufacturing errors, tolerances and the like. The flange on member 15 is undercut as shown at 34 to accommodate the eccentric 37 so as to insure that the member 35 will be drawn tightly against the member 15. The free end of the member 35 projects laterally therefrom as indicated at 41 to provide on anchoring hook which extends into the opening 29 in the adjusting cam 25. The member 35 is constructed of spring steel for a purpose to be described hereinafter.

In the position of the parts shown in Figure 1, the hooked end 41 of the tension member 35 is engaging the stop 31. The force applied to the cam 25 by the springs 25 through the tension member 35 rotates the cam until the line of action of the member 35 coincides with a line through eccentric 37 and stud 21. In this position of the parts, the indicia on the flange 26 aligned with the opening 27 will read Low or Thin, signifying that the nozzle is in the low position or is adjusted for thin carpeting. It now a force is applied to the rear of the cleaner body, either by the foot of the operator applied to any point thereon above the wheels 12 or by a direct downward thrust upon the handle 5 when the same is in vertical position, the rear of the cleaner will be depressed against the force of the springs 20 into the position illustrated in Figure 2. As the cleaner body depresses to the position of Figure 2, the hooked end 41 of the member 35 rides along the rear edge of the member 32 and up to the peak of the pointed member 33 which action flexes the spring member 35 toward the rear of the cleaner body. As the cleaner is depressed substantially to the limits permitted by springs 20, that is, a very slight amount greater than the depression illustrated in Figure 2, the end 41 of the member 35 rides over the peak of the point 33 and then snaps to a position forwardly of the tip of themember 33. If the cleaner is now released, the member 41 rides down the forward side of

members

32 and 33 into engagement with the stop 30 and then rotates the cam 25 to the position illustrated in Figure 3 which will position the indicia reading Thick or High on the flange 26 in alignment with the sight opening 27; that is, the cleaner is now adjusted for operation in the high nozzle or thick carpet cleaning position.

As shown in Figures 1 and 3, the extension 19 is in the passageway 8 in both adjusted positions of the nozzle, thus barring entry of the converting tool under these circumstances. As shown most clearly in Figure 2, the extension 19 is very considerably below the passageway 8 when the rear of the cleaner is depressed sufiiciently to change the nozzle adjustment. Thus it is unnecessary to depress the cleaner to the extent of altering the adjustment in order to remove the arm 19 from the passageway 8 to effect conversion. Once the converting tool is inserted, the rear of the cleaner is released and the arm 19 engages the underside of the converting tool which maintains the spring 20 depressed to a somewhat lesser extent than that shown in Figure 2 with the nozzle 2 elevated so far above the supporting surface that the agitator 3 will not operate upon such supporting surface. The act of converting to oti-the-surface czeaning does not alter the adjusted setting of the adjusting mechanism and the cleaner returns to its previously adjusted position as soon as the converting tool is withdrawn.

When returning from the position of Figure 3 to the position of Figure 1, it is only necessary to depress the rear of the cleaner as before in which event the tension member 35 rides up the forward side of the

members

32 and 33, flexing towards the front of the cleaner body, until it rides over the point on the end of the member 33 and then engages the stop 31, when the rear of the cleaner is released, and restores the parts to the Figure 1 position.

The rear wall of the cross member 1.5 of wheel support bracket 14 is provided with a slot 43 directly underlying the hook 41 to receive the downwardly extending portion of the cam 25 when the rear of the cleaner body is depressed as indicated in Figure 2 for the purpose of changing the adjustment of the rear wheels.

It is to be noted that a change of adjustment may be made by applying pressure in any number of ways by the foot or hand directly upon the cleaner body or by a downward thrust applied through the handle but that the cleaner must be depressed substantially as far as it can go in order to actuate the adjusting mechanism. It is important that the amount of depression of the rear of the cleaner required to change the nozzle adjustment be close to the maximum possible to permit full functioning of the springs 20 when operating the cleaner over floor obstructions and also in aiding the same to start on a forward stroke by momentarily raising the nozzle to break the suction in response to the downward component of the handle thrust without altering the nozzle adjustment.

The stud 38 and cam 37 is intended solely as a factory adjusting means to adjust the position of the hook 41 for a particular cleaner. After this device is once set and locked, further manipulation thereof should not be required as its primary function is to compensate for manufacturing inaccuracies, tolerances, relations and the like.

Referring now to Figures 6 to 8, inclusive, a modified form of the invention is illustrated which differs from the previously described form of the invention only with respect to the means provided for adjusting the rear wheels. The cleaner structure proper of this form of the invention is identical with that disclosed in Figure 1. Consequently, those portions of the device of Figures 6 to 8 which are identical with the previously described elements of Figures l to 5 are identified by identical reference characters distinguished by the addition of a prime.

The rear wheels 12 are carried by pivot pins 50 which are supported adjacent the rear ends of the side arms 51 of a wheel supporting bracket. The arms 51 are connected at their rear ends by a cross arm 52 to form a generally U-shaped wheel supporting bracket. Each arm 51 is pivotally carried upon a pin 52 mounted in a boss 53 depending from the underside of the fan casing and exhaust passageway structure One of the arms 51 has an extension 55 which extends into the converter passageway 8' in order to bar insertion of a converting tool except under certain conditions to be specified hereinafter. A pivot stud 57, see Figure 8, is threadedly mounted in the side wall of the structure 10 slightly forwardly of and above the rear wheels 12. A flanged disc 58 is pivotally mounted upon the stud 57 and is held against accidental movement by the friction of a spring washer 59 hearing on one face of the disc 58 within the peripheral flange 60 thereof. The flange 60 carries a plurality, three illustrated, of inwardly directed lugs 61 which receive mounting screws 62 for securing a cam plate 63 to the indexing disc 58. The cam plate 63 is provided with 'a plurality of arcuate slots extending different distances from the center thereof toward its periphery. The short slots 65 are utilized in a manner to be described hereinafter to adjust the apparatus for conversion to ofl-the-floor cleaning. The intermediate slots 66 are utilized to adjust the apparatus for operation upon thick floor coverings; that is, the high nozzle operating position, and the long slots 67 are provided to adjust the nozzle for operation upon thin floor coverings; that is, the low operating position of-the nozzle. As shown most clearly in Figure 6, the :cam 63 is provided with three sets of

slots

65, 66 and 67. The central portion of the cam 63 is cut out to provide a point of merger for all of the adjustable slots therein and also to provide an opening which receives a guide projection 68 extending outwardly from the stud 57 through the cam plate 63. One face of the projection 68 is cut away at 69 to form a curved guide member for a purpose to be described hereinafter.

One of the bracket arms 51 adjacent the cam 63 is provided with a slot 70 opening through the bottom portion thereof which receives one end of a crank arm 71. The arm 71 is seated in the upper end of the slot 70 by means of a bracket 72 which is secured to the underside of the cross member 52 and has a tongue portion projecting into the slot 70 to maintain the end of the crank 71 seated therein but freely pivotal. The end of the crank 71 extending through the slot 70 is provided with a rearwardly projecting counterweight section 74 which tends to rotate the crank 71 in a counter-clockwise direction as viewed in Figure 6. The free end of the crank 71 is reduced in diameter and supports -a flanged roller 75 engaged in one of the slots of thecarn 63 as illustrated in Figures 6 and 8. In the position of the parts illustrated in Figure 6, the roller 75 is engaged in one of the slots 67 and the springs 20' have projected the wheels 12' away from the main body 1' of the cleaner to the maximum extent permitted.

When the rear of the cleaner is pressed against the springs 20' either by foot pressure applied generally to the rear of the body structure or hood structure 4' or by a vertically downward thrust applied through the handle 5', the roller 75 rides up to theend of whichever of the slots it engages at the moment and is rocked by weight 74 in a counter-clockwise direction in the clearance space provided by the guide 69 to engage the roller 75 in the next succeeding slot in the cam 63 considered in a clockwise direction. With the parts positioned as illustrated in Figure 6, a depression of the rear of the cleaner to the maximum amount permissible and a release thereof shifts the roller 75 into the slot 66. When the cleaner is released, the springs 20 extend the wheels 12 away from the body 1' causing the roller to ride down to the bottom of the slot 66, during which the cam 63 and wheel 58 are rotated in a counter-clockwise direction against the frictional drag of the spring 59 until the portion of the member 71 in the slot 70, roller 75 and center of the stud 57 are in substantial alignment.

The foregoing series of operations will change the nozzle adjustment from the low, or thin carpet, cleaning position to the high, or thicl: carpet, cleaning position. The next succeeding operation of the adjusting mechanism caused by a full depression of the rear of the cleaner will ride the arm into one of the slots 65 which will then position the parts in the manner illustrated in Figure 7 which is the position in which the parts are held for conversion for otf-the-fioor cleaning. Under these conditions, the short slots 65 hold the nozzle in a high nonsurface engaging or inoperative position and hold the barrier 55 beneath the bottom wall of the converter passageway 8 to allow insertion of a converter for offthe-floor cleaning.

The cross bar 52 is provided with a cut-out portion 77, see Figure 8, to accommodate the disc 58 and its appurtenances when the rear of the cleaner is fully depressed.

The flange 60 on the wheel 58 is provided with suitable indicia each positioned to be aligned with a sight opening 78 when a corresponding one of the slots on the cam 63 is in operative position to indicate the condition of the nozzle to the operator.

In this form of the invention, successive complete depressions followed by immediate release of the rear of the cleaner serves to rotate the cam 63 in a counter-clockwise direction step by step sequentially altering the nozzle adjustment from low to high to conversion and then repeating three times for a complete revolution of the adjusting cam.

The form of the invention illustrated in Figures 9 to 11 discloses a third arrangement for adjusting the nozzle automatically in response to a predetermined depression of the rear of the cleaner body structure. The cleaner body proper and its appurtenances are identical with that illustrated in Figure 1. Consequently, the parts of the apparatus of Figures 9 to 11 which are identical with corresponding parts of the apparatus of Figure 1 are given the same reference characters distinguished by the addition of a double prime.

In this form of the invention, the rear wheels 12" are carried by short pintles 8t projecting outwardly from opposite side of a U-shaped rear wheel supporting bracket 81 which is pivotally mounted upon pins 82 carried by downwardly extending bosses 83 on the air duct and fan housing structure 10". The U-shaped bracket 81 has an extending leg or arm 85 which extends through a slot into the conversion duct 8" in order to bar the insertion of a converting tool except under conditions to be described hereinafter. The springs 29', which separate the rear wheels 12" from the cleaner proper to the limits allowed by the adjusting mechanism, bear between the underside of the air duct 10 and the rear cross bar portion of the U-shaped bracket 81.

A mounting boss 86, as shown most clearly in Figure 11, projects laterally from one side of the air duct 1d and threadedly receives a mounting stud 87. The stud 87 pivotally supports an adjusting cam disc 88 which has a central flange portion 39 bearing on the stud (57. A flange disc 90 is provided with a central mounting flange 91 press fitted or otherwise secured to the flange 89 to insure that the discs 949 and 88 will rotate as a unit.

The peripheral flange 92 of the disc 90 is positioned to underlie the sight opening 27" in order that the operator may determine the adjusted position of the nozzle from suitable indicia impressed or otherwise applied to the flange 92. The flange 92 is also provided with a plurality of inwardly extending tongues 93 which are first cut from the'disc 9t and flange 92 and then pressed inwardly as shown most clearly in Figure 9 to provide spaced stop shoulders 94. The stop shoulders 94 are positioned to be engaged by a small leaf spring 95 se- 7 prevent counter-clockwise rotation of the disc 90 as viewed in Figure 9.

The adjusting cam 88 is provided with four projecting

hook sections

96, 97, 98 and 99, positioned differing distances from the axis of the mounting stud 87.

The wheel supporting bracket 81 is provided with a downwardly dished portion 101 beneath the indicating flange adjusting cam structure which houses and supports a mounting pin 102. A torsion spring 103 is wrapped around the pin 162 and has one end 104 anchored to the bracket 81. The end 105 of the spring is elongated and is provided with a hooked end portion 106 adapted to engage in the adjusting hooks on the adjusting cam 88. In the position of the parts illustrated in Figure 9, the hooked end 106 of the spring 193 is engaged in the catch 99 of the adjusting cam. The force of the rear supporting spring 29" acting between the bracket 81 and cleaner exhaust duct 10' produces substantial alignment between the axis of the stud 87, the catch 99 and the elongated arm portion 105 of the spring 102. With the parts in this position, the nozzle 2 is in a normal cleaning position which serves adequately for most coverings. A direct vertical thrust applied to the rear of the cleaner, either by the foot or through the handle 5", will depress the same against the spring 20 which action will cause the hooked end 106 of the retaining spring to rise along the curved edge of the adjusting cam 88 connecting the

catches

99 and 96 until the end 106 rises over the edge of and engages the catch 96. When the cleaner is released, the force of the springs 20" rotates the catch 96 into its lowermost position in which it is aligned with the section iii; of the retaining spring and the axles of the stud $7. This is the position of the parts illustrated in Figure of the drawing. As the hooked end of the retaining spring rides along the edge of the adjusting cam in travelling from one of the catches to another, it applies a force to the adjusting earn tending to produce rotation thereof which is prevented by the spring 95 engaging one of the tongues 93 and shoulder 94. The spring 95 yieldingly resists clockwise rotation of the cam 88, as viewed in Figure 9, and absolutely bars counter-clockwise rotation by engaging shoulders 94.

Successive depressions of the rear of the cleaner to substantially the full amount permitted thereby engages the hooked end 106 of the retaining member with the

catches

95, 97, 98 and 99, successively. As shown most clearly in Figure 10, the converter barrier 85 is positioned below the converter passageway 8 when the catch 96 is engaged by the hook 106. At the same time the nozzle 2" i positioned so far above the supporting surface that the nozzle and the agitating device 3" will not engage or act upon the surface covering. In all other adjusted positions of the nozzle, the barrier 85 lies within the confines of the converter passageway. The catches 97,

98 and 99 correspond to thick, thin and normal cleaning positions respectively.

In Figure 10, angularly related lines are drawn from the point of contact of the front wheels 9" with the supporting surface outwardly under the suction nozzle and agitating device to indicate the relative position of the agitating device relative to the supporting surface in the various adjusting positions of the wheel positioning mechanism. These lines are labelled Thin, Normal, and Thick and Oif-the-Floor cleaning, reading downwardly, which correspond to

catches

98, 99, 97 and 96 respectively and refer to the position of the nozzle and agitator for surfaces covered with relatively thin carpeting or rugs, normal or average carpets, very thick and deep pile carpets, and the inactive off-the-floor cleaning or converting position, respectively.

The wheel adjustment has been disclosed in each modification of the invention as being applied to the rear wheels which is the preferred arrangement, but the front wheels may be adjusted by the same means to effect nozzle adjustment if desired. If the front Wheels are adjusted, the direction of the adjustment is reversed, i. e. projecting the front wheels away from the main body of the cleaner raises the nozzle Whereas the nozzle is lowered when the rear wheels are projected away from the main body.

In each form of the invention, the nozzle is adjusted progressively through a series of adjusted positions in response to successive depressions of the rear of the cleaner-accomplished by pressure applied through the handle or to any part of the cleaner body rearwardly of the front whcels-to a predetermined degree which positions the rear wheels closer to the cleaner body than will be the case under any practical condition of use and operation.

While the invention has been illustrated and described in detail herein, it is not to be limited thereto but various changes may be made in the construction, design and arrangement of parts without departing from the spirit of the invention or the scope of the appended claims.

I claim:

1. In a suction cleaner having a body portion including a surface cleaning device at the front thereof, front and rear surface engaging means for supporting said body portion, means movably mounting said rear surface engaging means on said body portion and means biasing said rear surface engaging means away from said body portion, the combination of mechanism for varying the relative positions of said rear surface engaging means and said body portion to adjust the operating position of said cleaning device including an adjusting member having a plurality of catches pivotally mounted on said body portion, said catches being positioned at different distances from the pivotal axis of said member, a latch member mounted on said movable means and adapted to engage said catches to rotate the engaged catch to an operating position and limit movement of said mounting means by said biasing means, and guide means for disengaging said latch member from a previously engaged catch and for engaging said latch member with a succeeding catch successively as said body portion is successively depressed against said biasing means to a predetermined position which is below any adjusted position of said body portion.

2. In a suction cleaner, a body portion having a clean ing device at the front thereof, front and rear surface engaging means carried by said body portion for supporting said body portion on a surface to be cleaned, means movably mounting said rear surface engaging means on said body portion and means biasing said rear surface engaging means away from said body portion, and an adjustable mechanism connecting said body portion and said rear surface engaging means to limit relative movement therebetween by said biasing means for adjusting the position of said cleaning device relative to a surface to be cleaned including a control plate pivotally mounted on said body portion and formed with a plurality of adjusting catches positioned at different radial distances from the pivoting axis of said plate and joined by guide surfaces, a holding member attached to said rear surface engaging means and engaging whichever of said catches is in an operative position to limit the action of said biasing means on said rear surface engaging means and biased to engage whichever of said guide surfaces extends between a catch in operative position and a succeeding catch whereby said holding member is guided from a catch in operative position into engagement with a succeeding catch when said body portion is depressed to a predetermined extent against said biasing means and said holding member rotates said control plate to position said succeeding catch in an operative position when said body portion is released to the action of said biasing means movably mounting said rear surface engaging means on said body portion, means biasing said mounting means away from said body portion, adjustable mechanism connected to said body portion and to said rear surface engaging means for adjusting the extent to which said biasing means moves said rear surface engaging means away from said body portion including a link, an adjusting member having a plurality of catches each separately engageable with said link tovary the adjustment of said mounting means, and means operated by successively depressing the rear of said body portion against said biasing means to the same predetermined position for releasing said link from a previously engaged catch and for engaging said link with a succeeding catch each time said body portion is depressed to said predetermined position.

4. Apparatus according to claim 3 in which said adjusting member is pivotally supported by said body por tion, said catches are arranged at varying distances from the pivotal axis of said adjusting member, and said link rotates said adjusting member to shift the engaged catch to an operating position when the rear of said body portion is released after each depression of the rear of said body portion to an extent suflicient to engage said link with a new catch.

5. Apparatus according to claim 3 in which said adjusting member comprises a plate, means pivotally mounting said plate on said body portion, said plate having an opening extending substantially around said pivotal mounting means except for an inwardly extending mounting portion to define catches on opposite sides of said mounting portion at different distances from said pivotal mounting means, said link being mounted on said mounting means for said surface engaging means and having a portion extending into the opening in said plate to engage said catches, said inwardly extending portion of said plate being formed to guide said link to the opposite side of said pivotal mounting means each time said body portion is depressed to said predetermined extent.

6. In a suction cleaner, a body portion having a cleaning device at the front thereof, front and rear surface engaging means carried by said body portion for supporting said body portion on a surface to be cleaned, means movably mounting said rear surface engaging means on said body portion and means biasing said rear surface engaging means away from said body portion, the combination of mechanism for varying the relative positions of said rear surface engaging means and said body portion to adjust the operating position of said cleaning device including a disc pivotally supported by said body portion having an opening and a pinrality of slots extending different distancesfrom said opening and having closed ends, a link carried by said rear surface engaging means having an end portion engaging in one of said slots to pivot the disc to an operating position to limit the extent of separation between said rear surfaceengaging means and said body portion produced by said biasing means, and means biasing said link to move said end portion relative to said disc whereby said link disengages from one of said slots and engages in another of said slots each time said body portion is depressed sufliciently to move said end portion into said opening in said disc.

7. In a suction cleaner according to claim 3 in which said adjustable mechanism comprises a disc pivotally supported by said body portion having a plurality of peripheral catches positioned at different radial distances from the pivotal axis of said disc and joined by smoothly curved guide surfaces, a spring link carried by said rear surface engaging means and having a portion engaging one of said catches to pivot said disc to an operating position to limit the extent of movement of said rear surface engaging means produced by said biasing means whereby said link will be guided by said guide surface t6 from one of said catches to another thereof each time said body portion is depressed to a predetermined degree.

8. The combination with a suction cleaner having a main body provided with a suction nozzle, pairs of front and rear wheels supporting said body above a floor, movable means connecting one of said pair of Wheels to said body including spring means urging said body upwardly away from said one pair of supporting wheels; of means for selectively holding said body and movable wheels in one of several different spaced apart relations including a pivotally supported detent member and a cooperating resilient latch member, one of said members being carried by said cleaner body and the other member being carried by said movable wheel supporting means, said pivotable detent member having a plurality of detents thereon at different radial distances from the pivot axis thereof, and means for flexing said resilient latch member and transferring the same from engagement with one of said detents and into engagement with a different one of said detents when said cleaner body is depressed in opposition to said spring to a predetermined extent and then released.

9. Nozzle height adjustment mechanism for use on a suction cleaner of the type having a main body supported by a plurality of wheels, said mechanism comprising a vertically movable support connecting one of said wheels to said body and including spring means biasing said Wheel support away from said body, adjustable means for limiting the movement of said body away from said one movably supported wheel including a rotatably supported detent member having a plurality of detents thereon at different radial distances from the pivot axis of said member, a latch member engageable with said detents, one of said members being carried by said cleaner body and one on said movable wheel support, and means for causing said latch to engage -a ditferent one of said detents and to index said rotatable detent member into a new position each time said cleaner body is depressed in opposition to said spring means to a predetermined extent and then released.

10. In combination, a suction cleaner having a main body provided with a suction nozzle at its forward end, a propelling handle pivotally connected to the rear end of said body, a pair of front supporting wheels for said body, a pair of rear wheels, a resilient support for said rear Wheels, said rear wheels and said resilient support being movable through two overlapping vertical ranges of movement of different extents, the shorter of said nanges being used in the normal operation of said cleaner to permit said body to pivot rearWamdly about said front wheels in response to downward pressure applied through said propelling handle, said longer range of movement being operative to actuate a nozzle height control mechanism, a nozzle height control mechanism operatively connected with said rear wheels comprising a pair of detents on said cleaner at different elevations, a lat-ch member operable to engage either of said detents and to limit the movement of said body away from said resiliently supported rear wheels, and means for adjusting said control mechanism to disengage a previously engaged detent and to engage a different one of said detents each time said body is depressed to the extent of said longer range of movement.

'11. In a suction cleaner according to claim 3 in which said adjustable mechanism comprises an adjusting mem ber pivotally mounted on said body portion and having a plunality of detents positioned at different distances from the pivotal axis of said member, a latch member selectively engageable with said detents for differently limiting the movement of said body away from said rear Wheels, one of said detents cooperating with said latch for holding said suction nozzle and agitator at a noncleaning level with respect to a floor covering and another of said detents cooperating with said latch for holding said nozzle in a cleaning position with respect to a floor covering, and guide means responsive to each de pression of the rear of said cleaner beyond a predetermined position to disengage said latch from a previously engaged detent and for guiding said latch into engagement with the other of said detents.

12. A resilient wheel and adjustable position control mechanism therefor for use on a suction cleaner comprising, a suction cleaner body, a wheeled carriage underlying and movable toward and away from said body, spring means urging said body away from said carriage against the weight of said body, said spring means providing a resilient support for said body capable of absorbing shock loads imparted to said carriage during movement over a floor and of permitting said body to be depressed through a substantial range during the normal operation of said cleaner, adjustable control means for limiting the movement of said body away from said carriage by said spring means comprising a two member linkage having one end connected to said body and another end connected to said carirage, said linkage including a lost motion connection between portions of said linkage members having a plurality of detents at spaced points along said lost motion connection arranged to permit said body and carriage to move within the aforesaid substantial range during the normal operation of said cleaner without changing a particular adjusted position of said linkage, and means for adjusting said linkage to disengage a previously engaged detent and to engage a different one of said detents each time of said body is depressed beyond the aforesaid substantial range of movement experienced during the normal use of said cleaner.

'13. In combination, a suction cleaner having .a main body and a suction nozzle, means for supporting said nozzle in different positions above a floor including .a wheeled carriage movable supported below said body, spring means biasing said body upwardly away from said carriage, a propelling handle pivotally connected to said body adjacent said carriage whereby downward pressure applied to said handle is effective to depress said body in opposition to said spring means, adjustable control means for limiting the upward movement of said body away from said carriage while leaving said body free for downward movement in opposition to said spring means, said control means comprising a linkage having one end connected to said body .and another end to said carriage, the intermediate portions of said linkage having a lost motion connection between a plurality of d'etents and a catch, said catch being selectively engageable with any one of said detents, and means for retaining said linkage in a previously adjusted position with respect to a previously engaged detent while said body is depressed through a normal cleaner operating range and for shifting said catch out of engagement with such previously engaged detent and into engagement with a different one of said detents in response to each depression of said body to a position beyond said normal cleaner operating range.

14. The combination defined in claim 13 wherein said linkage comprises two members one of which is a cantilever spring having a hooked free end selectively engageabie with any one of said detents and forming part of said lost motion connection, and wherein said lost motion connection includes means for guiding the hooked free end of said cantilever spring successively from one detent to another upon successive depress-ions of said cleaner body beyond said normal cleaner operating range.

15. In a suction cleaner, a body member having a cleaning device at the front thereof, means carried by the body member for supporting the same on a surface to be cleaned including a surface engaging member adjacent the rear of the body member, means biasing said rear surface engaging member away from the body member, and an adjustable mechanism connected between the body and rear surl ace engaging members for adjustably varying the separation thereof induced by said biasing means fior adjusting said cleaning device relative to a surface to be cleaned comprising a catch on one of said members, a plurality of stops on the other of said members each adapted to be engaged with the catch to limit separation of the members by the biasing means and each of said stops being positioned to hold said members at different amounts of separation therebetween when engaged by the catch, and guide means actuated by each depression of the rear of the body member to the same fixed predetermined position for guiding the catch out of engagement with the previously engaged stop .and into engagement with a succeeding stop.

16. In a suction cleaner, a body portion having a cleaning device at the front thereof, front and rear surface engaging means carried by said body portion for supporting said body portion on a surface to be cleaned, means biasing one of said surface engaging means away from said body portion, and an adjustable mechanism connecting said body portion and said one surface engaging means to limit relative movement therebetween by said biasing means for adjusting the position of said cleaning device relative to a surface to be cleaned including a link, a plurality of catches selectively engageable by said link for adjusting the position of said cleaning device, and guide means actuated by successively depressing said body portion against said biasing means to the same predetermined position and releasing said body portion for disengaging said link from a previously engaged catch and for guiding said link into engagement with a succeeding catch.

17. Apparatus according to claim 16 in which said surface engaging means is at the rear of said body portion, said link is carried by said surface engaging means, said catches are on a control member movably mounted on said body portion and positioned to hold said surface engaging means in different positions relative to said body portion when in an operative position and engaged by said link, and said guide means includes a guide surface on said control member whereby said control member is moved by said link to position each succeeding catch in operative position when said body portion is released to the action of said biasing means after each depression of the body portion to said predetermined position.

18. The combination with a suction cleaner of the type having a main body provided with a suction nozzle, means including at least one movable wheel means supporting said cleaner; of adjustable means for controlling the position of said movable wheel supporting means with respect to said body comprising, a stop member having a plurality of detents thereon, a latch member selectively engageable with said detents, one of said members being supported on said cleaner-body and one being carried by said movable Wheel supporting means, spring means for biasing said cleaner body away from said wheel supporting means to the extent permitted by said latch and stop members, and means operable by the depression of said cleaner body to the same predetermined position in opposition to said spring means for guiding sai-d latch out of engagement with a previously engaged catch and into engagement with a succeding catch each time said cleaner body is depressed to said predetermined position.

References Cited in the file of this patent UNITED STATES PATENTS 2,067,990 Taylor Ian. 19, 1937 2,172,911 Kirby Sept. 12, 1939 2,172,973 Hays et al Sept. 12, 1939 2,325,821 White Aug. 3, 1943 2,389,877 Snyder Nov. 27, 1945 2,409,082 Troxler Oct. 8, .1946 2,474,448 White June 28, 1949 FOREIGN PATENTS 532,691 Great Britain Jan. 29, 1 941