US 3649995 A
A floor cleaning machine having a scrubbing means near the forward end of the body, a system for supplying a cleaning solution to the scrubbing means, and a system for recovering the used solution, said latter system having in conjunction therewith a squeegee device near the rear end of the machine, and a spring bar connected to a support near the center of the machine on the underside thereof and applying a downward pressure on the device. A means is included in the mechanism for adjusting the downward pressure applied by the spring bar to the device, and the spring bar, while applying pressure to the device, flexes to permit the squeegee device to readily pass over uneven floor areas.
Description (OCR text may contain errors)
United States Patent [451 Mar. 21, 1972 [son  FLOOR MAINTENANCE MACHINE  Inventor: Wayne Ison, Elkhart, Ind.
 Assignee: Keltec, Inc., Elkhart, Ind.
 Filed: Feb. 16, 1970 i  Appl. No.: 11,506
 0.8. CI ..l5/320, 15/340  Int. Cl. ..A47l 7/00  Field ofSearch ..15/4,50,52,320, 340,98
 References Cited UNITED STATES PATENTS 3,496,591 2/1970 Sheler ..15/320 2,317,843 4/1943 Backlund 15/320 X 2,930,055 3/1960 Follen et al.. ....l5/320 X 3,290,716 12/1966 Cain ..l5/320 X Primary Examiner-Dave W. Arola Attorney-Hobbs & Green and Kemon, Palmer & Estabrook [5 7] ABSTRACT A floor cleaning machine having a'scrubbing means near the forward end of the body, a system for supplying a cleaning solution to the scrubbing means, and a system for recovering the used solution, said latter system having in conjunction therewith a squeegee device near the rear end of the machine, and a spring bar connected to a support near the center of the machine on the underside thereof and applying a downward pressure on the device. A means is included in the mechanism for adjusting the downward pressure applied by the spring bar to the device, and the spring bar, while applying pressure to the device, flexes to permit the squeegee device to readily pass over uneven floor areas.
9 Claims, 6 Drawing Figures PATENTEBMARZI 1912 SHEET 1 OF 3 I N VEN TOR.
WAYNE ISON I/ Z a 74 g;
ATTORNEYS PATH-115mm 1972 3,549,995
SHEET 2 OF 3 M ll L INVENTOR. WAYNE ISON BY m m TTORNEYS PATENTEDMARZI I972 3,649,995
' sum 3 UP 3 I ATTORNEYS I FLOOR MAINTENANCE MACHINE Floor cleaning machines for industrial use generally utilize two counter-rotating, power driven brushes at the forward end, which are supplied with a cleaning solution from a tank on the machine, and a solution recovering mechanism including a squeegee device mounted at the rear from which the dirty solution is delivered to a separate tank on the machine. The squeegee devices used on the prior equipment were often ineffective in recovering all the used cleaning solution from the floor, frequently leaving streaks or puddles of solution, particularly in depressions in the floor and along the path of the machine where they were maneuvered into various turns and lateral positions. Floor irregularities, such as roughness and small protrusions, often permit the dirty solution to pass beneath the blades on the squeegee and form streaks or spots on the floor. Further, in the prior machines, the squeegee is extended beyond the sides of the machine to give the squeegee sufficient breadth to recover the solution while the machine negotiates turns and other maneuvers. However, the protruding ends of the squeegee frequently bump or contact walls, posts, and other obstacles and cause damage thereto, or the squeegee is itself damaged by the impact. it is therefore one of the principal objects of the present invention to provide a solution recovery mechanism which will respond immediately and effectively to adapt itself to slight or moderate floor depressions and protrusions and roughness and thereby give optimum performance under such adverse operating conditions, and which is so constructed and mounted on the machine that it will constantly apply a pressure to the mechanism regardless of the angularity of the mechanism relative to the principal axis of the floor cleaning machine, and further, that it will effectively follow the path of the floor surface cleaned by the brushes and will be readily deflected when bumped or sideswiped as the machine is maneuvered along walls and around posts and other objects or obstacles.
Another object of the invention is to provide a floor cleaning machine with a squeegee operating mechanism having a spring bar which applies a positive pressure to the squeegee and which includes a means for adjusting the positive pressure on the squeegee to adapt it to various operating conditions.
Still another object of the invention is to provide a squeegee structure which applies a substantially uniform, yieldable pressure to the floor throughout its length and which will swing freely within a relatively wide horizontal arc to follow the path cleaned by the brushes, as the machine is maneuvered on the floor, and to deflect vertically to adapt to depressions and rises in the floor.
A further object is to provide a relatively simple, troublefree solution recovery apparatus for floor cleaning machines, which can be readily cleaned, serviced and adjusted, and which is compact and can easily be incorporated in floor cleaning machines within relatively limited space.
Another object of the invention is to provide, in a floor cleaning machine having two counter-rotating brushes, an efficient solution recovery device which causes the solution to flow to the center part thereof and through laterally spaced ports where it is picked up and delivered to a tank on the machine, and which is provided with a squeegee device movable in all directions for removing water, dirt and cleaning liquid from the floor after completion of the scrubbing operation performed by the brushes.
Additional objects and advantages of the invention will become apparent from the following description and accompanying drawings, wherein:
FIG. 1 is a side elevational view of a floor cleaning machine showing a portion of the housing broken away for the purpose of better illustrating the mechanism associated with the present invention;
FIG. 2 is a top plan view of the cleaning machine shown in FIG. 1;
FIG. 3 is an enlarged fragmentary side elevational view showing the mechanism involved in the present invention;
FIG. 4 is a horizontal fragmentary cross sectional view taken on line 4 4 ofFlG. 1;
FIG. 5 is a bottom plan view of the solution recovery mechanism involved in the present invention; and
FIG. 6 is a fragmentary elevational view of the machine and an elevational view of the solution recovery mechanism shown in FIG. 5.
Referring more specifically to the drawings and to FIGS. 1 and 2 in particular, numeral 10 designates generally the present floor cleaning machine, and 12 the sweeping or scrubbing mechanism, having a pair of rotating brushes l4 and 16 driven by an electric motor or other suitable power means enclosed in compartment 18 of body 20, the two brushes consisting of bristle portions 22, backing plates 24 and hubs 26 through which the brushes are driven by a motor in compartment 18. As the two brushes rotate, water flowing from a water supply system, including a tank in the upper part of body 20, is supplied to the brushes through conduits connected to hubs 26 in the respective brushes. The water, on reaching the brushes, is distributed therein by centrifugal force, and is used in the scrubbing operation as the machine is maneuvered over the floor. The two brushes are counterrotating, and the water discharged through the brushes tends to collect in a stream trailing the space between the two brushes as the machine is moved generally forwardly over the area being cleaned. For the purpose of the present description, the two brushes and water supply system may be considered conventional, and hence the details thereof will not be described herein.
The machine may be power-driven or pushed by the operator, and, in the machine shown in the drawing, the machine is supported by two main wheels 34 and 36 mounted on an axle 38 extending transversely beneath the body of the machine and connected thereto by several supports (not shown). Two casters 40 and 42 including wheels 44 and 46, respectively, support the rear end of the machine body and permit the machine to be maneuvered effectively over the area to be cleaned and along and around obstacles in the area. The two wheels 44 and 46 are connected to the body by bifurcated members 48 and pivot members 50 attached to the underside of body 20.
The water recovery mechanism designated by numeral 60 consists generally of a squeegee device 62 and a control device 64. The squeegee device consists of two front laterally spaced blades 66 and 68 and an intermediate blade 70 interposed between and spaced from blades 66 and 68. The front blades are supported by a housing 74 and are secured to downwardly extending flanges on the housing by a plurality of bolts or rivets 75. A rear blade 78 spaced from front blades 66 and 68 is mounted on a downwardly extending flange on housing 74 and is secured thereto by a plurality of bolts or rivets. The blades are preferably made of rubber or plastic material and are sufficiently flexible that, as they move along the surface of the floor, they will conform readily to the irregularities and contour to form a yieldable seal therewith. Chamber 76 is substantially enclosed when the machine is in operation, with the exception of ports 78 and 80 at the inner ends of blades 66 and 68. The two ports thus formed constitute inlet openings for the dirty solution to enter space 76.
By a mechanism to be described hereinafter, the squeegee blades are pressed downwardly toward the surface of the floor with sufficient force to create a scraping action, which will not only effectively remove the water, but will also remove particles of dirt and other foreign matter tending to adhere to the floor, as well as any dry material which may be engaged by the squeegee device. Space or chamber 76 is connected to a water recovery tank in body 20 by a flexible tube 84 secured to nipple 86 which in turn is connected to the space 76. The dirty solution collected in space 76 is drawn from said space through tube 84 to the solution recovery tank by a vacuum pump or other suitable pump mechanism disposed in the housmg.
.The squeegee device 62 is generally arcuate shaped and is connected by a resilient bar or shaft 90 to a swivel joint 92 pivotedly secured to axle 38. The rear end of spring bar 90 is rigidly connected to the squeegee device by pin 94 extending downwardly through fixture 95 and through a hole in the end of bar 90. The joint 92 consists of a vertical bearing housing 96 pivotally secured to a horizontal bearing housing 98 mounted on shaft 38 and held in axial position thereon by sleeves 100 and 101 at opposite ends of housing 98. Housing 96 contains a vertical shaft 102 on which the housing rotates freely and on which it is retained by a nut 104 threadedly received on the lower end of the shaft, the shaft being rigidly connected to housing 98 and projecting downwardly therefrom. The bar 90 is resilient, preferably constructed of spring steel so that it will flex upwardly and downwardly, as illustrated in FIG. 3 in broken lines, and is connected to housing 96 by bolts 105 and 106 and lug 108 attached to housing 96. The bar also can twist slightly as it applies pressure to the squeegee device. The joint 92 permits shaft 90 to swing freely horizontally, and the fiexure of the spring bar 90 permits the squeegee to adjust in vertical directions. This combination of features and action permits the squeegee device 62 to tilt and to move freely laterally and vertically as it follows the path of the machine and traverses depressions and rises and other irregularities in the floor.
With the device 64 mounted in the foregoing manner, the squeegee device 62 is capable of moving freely laterally in a generally arcuate direction and is readily deflected when a projecting end thereof contacts an object or obstacle or when the machine moves along the wall or sideswipes an object. Wheels 107, shown only in FIGS. 1 and 2, are rotatably mounted on shafts 109, which in turn are mounted on the upper side of the outer ends of housing 74, and roll when they contact an object such as a wall, thereby protecting the wall as the device moves along the floor closely thereto to remove the dirty solution. The wheels also facilitate effective deflection when the respective end of the squeegee device contacts an obstacle. It is seen that the center of the arc of the squeegee device is on the axis of shaft 38, thus causing the device to move longitudinally in line with its own curvature when it is deflected to the right or left as the machine is maneuvered over the area being cleaned. This facilitates effective removal of the dirty solution, regardless of the various positions into which the machine is maneuvered during the cleaning operation. The pressure of the squeegee blades on the floor is controlled by the resilience and flexure of spring bar 90 and by the pressure adjustment means indicated by numeral 110. This adjustment means consists of a lever 112 rigidly connected to housing 98 and projecting upwardly therefrom and a shaft 114 pivotally connected to the upper end oflever 112 and extending through a rigid bracket 116 mounted on the underside of the body of the machine. The end of shaft 114 opposite lever 112 has a threaded portion 118, and a nut 120 is threaded onto the threaded portion and seated against bracket 116. When nut 120 is tightened against the side of bracket 116, it moves rod 114 and lever 112 to the left as viewed in FIG. 4,
V thus rotating the lever and housing 98 in the counterclockwise cleaned. When the nut is loosened, the resiliency of the spring bar reacting against the squeegee device causes housings 96 and 98 and lever 112 to rotate in the clockwise direction, as viewed in FIG. 4, thus retaining the nut against the adjacent side of bracket 116, thereby relieving or reducing the pressure applied by the spring bar to the squeegee device and hence reducing the pressure applied by the squeegee device onto the floor. The spring bar 90 may be made of any suitable material, preferably somewhat wider than the thickness thereof. The spring bar, however, will tend to twist sufficiently to permit the squeegee device to adapt to uneven floor conditions. The degree of flexing of spring bar 90 in a normal operating condition depends upon the resiliency of the metal forming the bar,
and by theproper selection of the spring bar characteristics, the resiliency or flexure may be varied over a wide range, and the vertical travel of the squeegee in performing the normal operation can likewise be varied over a wide range.
In the cleaning operation, the two counter-rotating brushes 14 and 16 are placed in operation, and the water-detergent solution is delivered to the brushes which are maneuvered by the operator over the area being cleaned. As the brushes rotate and the machine is moved forwardly, the dirty solution accumulates in a stream trailing the space between the two brushes. As the squeegee device reaches the stream, the dirty water is deflected laterally by blades 66, 68 and/or 70 to ports 78 and 80 and is emulsified and sucked inwardly into space 76 where it is removed through tube 84 to a collecting tank in body 20. The two lateral blades 66 and 68, which are both arcuate and positioned with the outer ends forwardly of the inner ends, cause the dirty solution to flow inwardly to ports 78 and 80. The intermediate squeegee 70 normally trails directly behind the space between the two counter-rotating brushes and thereby performs an effective scraping action on the floor for removing any foreign material left by the two brushes in the space therebetween. The dirty solution and foreign material pass outwardly laterally along the intermediate blade to ports 78 and 80 and are drawn therethrough into space 76. Any foreign material or dirty solution passing under the blades 66, 68 and 70 is caught in space 76 in front of blade 78, the latter blade performing the function of recovering any material remaining after the front blades have passed over the floor.
As the machine is maneuvered over the area being cleaned and is turned either to the right or the left, the squeegee device swings in the opposite direction relative to the body of the machine to follow effectively the path cleaned by the two brushes. Since the squeegee device is mounted on the spring bar 90, it effectively adapts itself to irregularities and to the contour of the floor. Sufficient pressure is applied by the spring bar onto the squeegee device to cause the blades to press firmly on the floor and to adjustto depressions, rises, roughness and, other irregularities in the floor. In the event either of the ends of the squeegee device engages an obstacle,
"the device is readily deflected laterally with little or no resistance to the obstacle, thereby preventing damage to the obstacle and/or to the cleaning machine.
While only one embodiment of the present cleaning machine has been described in detail herein, various changes and modifications may be made without departing from the scope of the invention.
Iclaimz l. A floor cleaning machine having abody, scrubbing means near the forward end of the body, a system for supplying a cleaning solution to thcscrubbing means, and a system for recovering used solution: a used solution recovery mechanism comprising a squeegee device extending laterallyacross the 1 rear part of the machine at the bottom thereof, a spring bar connected at one end to said device, a support beneath said body forthe other end of said spring bar, said support means including a bearing means pivotally mounting said bar on said support for angular movement of said bar on a substantially horizontal plane, and a means near said other end resisting the upward angular movement of said bar and causing said bar to apply a yieldable positive downward pressure on said device.
2. A solution recovery mechanism in a floor cleaning machine as defined in claim 1 in which said second mentioned means includes means for varying the downward pressure applied by said bar on said device.
3. A solution recovery mechanism in a floor cleaning machine as defined in claim 2 in which said support beneath the body for the said other end of said spring bar includes a pivot means on a horizontal transverse axis.
4. A solution recovery mechanism in a floor cleaning machine as defined in claim 3 in which said bearing means is moveable angularly on said horizontal pivot means and said second mentioned means includes means for adjusting the angularity of said bearing means to vary the downward pressure of the spring bar on said device.
5 A solution recovery mechanism in a floor cleaning machine as defined in claim 4 in which said'second mentioned means includes a lever spaced angularly from said spring bar connected to said bearing means and adjusted to vary the downward pressure on said device.
6. A solution recovery mechanism in a floor cleaning machine as defined in claim 5 in which said second mentioned means includes a rod having a threaded portion thereon attached to said lever and a threaded means mounted on said rod for varying the angularity of said lever with respect to said spring bar.
7. A solution recovery mechanism in a floor cleaning machine as defined in claim 1 in which said spring bar is constructed of spring steel and flexes as said squeegee device traverses uneven floor areas.
8. A solution recovery mechanism in a floor cleaning machine as defined in claim 6 in which said spring bar is constructed of spring steel and flexes as said squeegee device traverses uneven floor areas.
9. A solution recovery mechanism in a floor cleaning machine as defined in claim 8 in which said cleaning machine has a pair of wheels and a transversely arranged axle for said wheels, and said pivot means is mounted on said axle.