WO2005107561A2 - Quick-change squeegee for floor scrubber - Google Patents

Abstract

A squeegee blade (15) is mounted to a mounting plate (11) carried by the frame of a floor scrubber by means of a structure which permits the blade to be changed quickly and without tools. A retainer member (13) is hinged to the mounting plate (11) for rotation between an open position permitting the blade to be replaced manually, and a closed position in which the retainer secures the blade in place for use. The retainer (13) is then secured to the mounting plate by means of a hand fastener which in the illustrated embodiment is an internally threaded retainer nut received on a threaded stud (32) fixed to the mounting plate (11). The nut is in the form of a knob (17) so that it may be tightened or loosened by hand.

Description

QUICK-CHANGE SQUEEGEE FOR FLOOR SCRUBBER Related Application This application claims the benefit of U.S. Provisional Application No.

60/565,045 filed on April 23, 2004 for "QUICK-CHANGE SQUEEGEE FOR FLOOR SCRUBBER".

Field of the Invention The present invention relates to floor scrubbers; and more particularly, it

relates to powered floor scrubbers for commercial or industrial use.

Background of the Invention Commercial floor scrubbers, particularly larger commercial floor scrubbers, are

self-powered machines which apply a solution of cleaning agent and water and then

scrub the floor with driven brushes. The spent solution is normally recovered by a

rear squeegee as the machine traverses the area being cleaned. As used herein, floor

scrubbers include both sweeper/scrubbers, which use one brush to remove loose,

larger debris and then wet-scrub the floor with one or more separate brushes, and

conventional scrubbers which do not sweep the floor prior to scrubbing.

The scrubbing action may be accomplished by cylindrical brushes rotated

about a transverse horizontal axis, or disc brushes (typically two or three per

machine) driven to rotate about vertical axes. Clean solution is usually applied to the

brush by conventional techniques, such as spraying or dripping. The dirty solution,

after recovery by the rear vacuum squeegee, is stored in a recovery tank. When the

machine is low or out of clean solution, the operator returns the machine to a

janitorial closet or similar location where the spent solution is discharged into a drain, and the machine may then be provided with a new quantity of cleaning solution for a subsequent run. The solution is worked into the floor to loosen grime

and dirt adhered to the floor by the driven scrub brush or brushes.

Larger commercial floor scrubbers are designed to make extended runs before refilling the clean solution tank and discharging the spent solution. These machines are designed for long use and for cleaning large areas.

As the solution beneath the machine is worked by the brushes, there is a

tendency for the spent solution to migrate laterally out from beneath the machine and

beyond the reach of the rear squeegee. Such an occurrence would leave streaks or

strips of spent solution and defeat the overall function and purpose of the machine. In order to improve the recovery of spent solution and to avoid leaving wet

areas, side squeegees have been developed and placed on the scrubber. Side squeegees have at least a section extending generally parallel to the direction of

machine travel for confining or containing the spent solution from migrating laterally

beyond the machine and keeping the solution within the reach of the rear pick-up

squeegee. To facilitate pick up of all water, the side squeegees typically have a rear

portion which is inclined rearwardly and inwardly toward the center of the machine

to route the collected water inwardly. The blade of the side squeegee typically is made of rubber or other suitable

material which becomes worn during use. In a typical side squeegee blade, the

bottom surface of the rubber blade is flat, defining a corner (or two) which forms a

working or floor contact edge. The blade is tilted laterally so that the working edge

of the blade is the effective portion of the blade for wiping the floor and containing the water, as with conventional squeegees. The working edge of the blade, of course,

scrapes along the floor surface during operation, and thus becomes a wear element

of the blade which requires periodic replacement.

Replacement of the squeegee blades can introduce inefficiency in the overall

cleaning operation, particularly if the blade requires special tools to replace the blade,

as has been the case in some prior or existing machines. In addition, inefficiencies

can be created if it is time-consuming or difficult manually to replace the blade.

Further, if the blade must be replaced by a new blade each time the working edge of

the blade becomes worn (which might be occur, for example, during use by an

operator's observation of streaks), it may be necessary for the operator to go to a

remote location to obtain a new blade, thus creating delay and adding cost to the

overall operation of the machine.

One suggested solution to the problems indicated above is that the replaceable

portion of the side squeegee includes a rubber or blade component which is attached

to a plastic track or retainer extending along the top of the blade. A metal receiver

on the scrubber mounts the plastic retainer and secures the blade in place. Once

engaged, the blade refill is secured in place by self-locking clevis pins inserted into

holes in the receiver at the forward and rear ends of the receiver. This structure adds

expense because it requires that the worn assembly, including the blade and the

plastic retainer then be discarded and replaced. This design also provides only a

single wear edge on each squeegee blade which is permanently attached to the

retainer in a predetermined angle so that the working edge of the blade is directed

toward the floor in the desired position for moving the spent cleaning solution. This type of system has been found to be inefficient, and therefore expensive, primarily

in that it has only a single wear edge per blade, and requires a specially designed (and

thus expensive) blade for replacement.

Another known system for a side squeegee of a floor scrubber includes a

rubber blade attached to a side frame of the machine by sandwiching the blade

against the frame using a metal strip or plate referred to as a retaining strip. The

retaining strip is manufactured with apertures that align with holes (either tapped or

through holes) in the squeegee retainer. The rubber squeegee blade has

corresponding, aligned apertures so that conventional threaded fasteners such as

bolts may be passed through the holes in the retainer and screwed into tapped holes

in the side frame. Alternatively, if holes in the side frame are not threaded, a bolt

can be passed through both the retainer, squeegee blade and the side frame, securing

the assembly together and clamping the squeegee blade to the side frame. In either

case, tools are required to replace or reverse the squeegee blade. If through holes are

used, two hand tools are required for loosening the bolts in order to replace a

squeegee blade, and it is cumbersome to replace the blade in this type of machine

because a wrench must be placed within the side frame to loosen and to secure the

squeegee blade and the retainer to the side frame.

In the case where untapped holes are formed on the side frame, nuts must be

placed on the inner side of the side frame, and tools are used to secure threaded bolts

to the nuts. In the case where threaded holes are used in the side frame, threaded

bolts must be secured unto the retaining frame of the machine using tools. Moreover,

the provision of tapped holes in the side frame add to the manufacturing cost of the machine.

Summary of the Invention

The present invention includes a rigid mounting plate which is fixed to the

frame of a floor scrubber and extends in the direction of travel of the machine. The

rear of the mounting plate is formed inwardly (i.e. toward the center of the machine)

at an angle to the direction of travel so that when the squeegee blade is mounted to

the mounting plate of the frame, water at the rear of the side squeegee is directed

inwardly toward the center of the machine, on both sides, as is generally known.

However, the mounting structure of the present invention permits the blade to be

changed quickly and conveniently, and without special tools.

To accomplish the quick change, a retainer bar (or, simply, "retainer") is hinged

to the mounting plate for rotation about a vertical axis, preferably forwardly of the

mounting plate so that the retainer can be rotated about the forward hinge axis

between an open position which permits the worn blade to be removed quickly and

without tool, and the new blade to be placed on the mounting frame, and a closed or

use position in which the squeegee is secured in the use position.

The retainer bar can be thus swung, when unlocked, to an open position,

permitting quick and easy replacement or reversal of the squeegee blade which is held

to the frame by a series of pins received in holes in the squeegee blade. One of the

pins affixed to the mounting frame is threaded and extends through the squeegee

blade. The threaded pin is preferably located toward the rear of the mounting plates. Once the blade is replaced, manually and without the need for tools, the

retainer is rotated to the closed position, thereby clamping the blade in place for use. The retainer is then secured to the mounting plate by an internally threaded retainer

nut, preferably in the form of a knob or wing nut, so that the operator can exert hand

leverage in securing the retainer bar to the mounting plate. The machine is then ready for further use. Another feature of the present invention is that the squeegee blade is reversible

in a fore/aft direction (and conceivably reversible in an up/down direction), thereby providing either two (or four) working edges on the same blade for reducing the cost

of replacement materials and eliminating the need to locate a new blade every time

a new working edge is required or desired, which normally is observed during use. Other features and advantages of the present invention will be apparent to

persons skilled in the art from the following detailed description of the illustrated

embodiment accompanied by the attached drawing wherein identical reference

numerals refer to like parts in the various views.

Brief Description of the Drawing FIG. 1 is a right, rear, upper perspective view of an improved right-side

squeegee assembly incorporating the present invention with the major components

in exploded relation, and with the retainer bar in the open or replacement position;

FIG. 2 is a plan view of the improved side squeegee structure of FIG. 1 , with

the front on the left, and the retainer bar shown in both the locked or use position

and the open or replacement position;

FIG. 3 is a front view of the improved squeegee structure of FIG. 1 ; and FIG. 4 is a close-up fragmentary frontal perspective view of the improved

squeegee, taken from above the connection between the mounting plate and the retainer, shown in exploded relation.

Detailed Description of the Illustrated Embodiment

Referring first to FIG. 1, there is seen an upper, right, rear perspective view

of a side squeegee mechanism for a floor scrubber designed to be used on the right

side of the scrubber and with the component parts in exploded relation. As used

herein, "right" and "left" refer to the right and left sides of an operator facing the

forward direction of travel of the machine. Thus, in FIG. 1 , the right side is toward

the lower right portion of the drawing. It will thus be understood that the assembly

shown in FIG. 1 is adapted for mounting to the right side of the machine, and that

the machine would be traveling toward the upper right corner of the drawing. A

corresponding left side squeegee mechanism in mirror image to that seen in FIG. 1,

would be mounted in a similar manner to the left side of the scrubber. Turning then to FIG. 1, reference numeral 10 generally designates an overall

right side squeegee assembly for a floor scrubber (including scrubber/sweepers). The

squeegee assembly 10 includes a mounting member or plate 11, a pivoting retainer

13, which is mounted to the mounting member 11 by means of a vertical hinge pivot

14, a squeegee blade 15, back-up strip 16, and a locking knob 17.

The mounting plate 11 is pivotally mounted by pins 30 to parallel arms 19,

which, in turn, are pivotally mounted to an extension F of the frame of the machine.

The parallel arm mount to the machine is conventional and may include a spring for

urging the squeegee in the use position while permitting it to swing rearward and

upward on arms 19 to overcome an obstruction.

Turning now to the squeegee blade 15, it may be of conventional design and material. That is, the squeegee blade 15 may be made of rubber or other flexible

synthetic or natural material of the type used as a floor squeegee in existing floor

scrubbers. The squeegee blade 15 includes an elongated, forward portion 18 which extends generally parallel to the direction of travel of the machine. Toward the rear

of the squeegee blade, approximately one quarter of the length of the squeegee blade

15 from the rear, the squeegee blade curves as at 20, when mounted, as will be

described, thereby leaving a rear or trailing portion 21 which is inclined rearwardly and toward the center line of the machine extending in the fore-to-aft direction. The

shape of the mounted blade 15 thus contains the water from lateral movement beyond the width of the machine by means of the elongated front portion 18, and

then, as the machine moves forwardly, the blade routes the retained, spent solution toward the center of the machine to insure recovery by the rear squeegee of the

machine which is conventional and not seen in the drawing.

As seen in FIG. 3, the bottom surface 23 of the squeegee blade 15 is generally

flat, as is the top surface, thus providing four ninety-degree corners for working edges

when engaging the floor. The bottom surface 23 includes an inner edge 24 and an

outer edge 25. The upper surface is similarly shaped as seen in FIG. 3. As also seen

in FIG. 3, the mounting of the squeegee assembly is such that the blade is tilted

slightly inwardly and upwardly from the floor which it engages so that in the

illustrated embodiment, the inner edge 24 of the blade is the working or floor-

contacting edge, and the bottom surface 23 typically does not fully engage the floor

surface except as the adjacent portion of the inner edge 24 may be compressed. It

is not intended that the outer edge 25 of the blade 15 engage the floor. However, as will be understood by persons skilled in the art, the blade 15, because it is flexible

and not rigid, may be reversed so that the outer edge and inner edge are reversed, thereby extending the useful life of the blade and obviating the need to locate a new

blade for replacement when the non-contacting edge has not yet been used. Further,

because the upper edge also has square corners, the blade may be inverted vertically for a total of four contact edges.

As best seen in FIG. 4, a flat plate 22 is welded to the front of mounting plate

11 to form an angled flange extending toward the center of the machine (i.e.

transverse of the direction of travel). The fixed, transverse plate 22 is provided with a pair of threaded studs 45 (FIGS. 3 and 4) fixed to the plate 22, and spaced

vertically and extending generally in the forward direction. A hinge plate 26 is

mounted by a fixed plate 39 to the forward portion 38 of retainer bar 13, by a hinge pin 40. Thus, hinge 14 is a conventional gate hinge which includes hinge plate 26

(FIG. 3) having apertures or laterally elongated slots 44 for receiving bolts 45 which

are secured by nuts 46 (FIG. 3). The slots 44 permit the squeegee assembly to accommodate squeegee blade/

retainer strips of different combined thicknesses, as will be understood. The

mounting plate 11 includes a central, generally flat and generally vertically extending

forward portion 27 and then a correspondingly shape inwardly and rearwardly

extending rear portion 29. Forward transverse mounting plate 22 is integral with the

forward end of the forward portion 27 of the mounting plate 11. Alternately, the plate 22 could be formed by bending the front portion of the mounting plate to form

a transverse flange on which studs 45 would be welded. Extending inwardly of the forward portion 27 are dowel pins 30 which mount the squeegee assembly to the swing arms of links 19 of the extension frame F of the machine.

Extending laterally outwardly of the mounting plate 11 , on both the forward

portion 27 and the rear portion 29 are a series of laterally spaced locating pins 31, 32 which are pressed into pilot holes formed in both the forward section 27 and the

rear section 29 of the mounting plate 11. The rear locating pin 32 may be externally

threaded to receive the internally threaded hand knob 17.

The pins 31, 32 and threaded stud 32 are arranged and located to receive the

squeegee blade 18 by passing through aligned holes 33 formed in the squeegee blade 15 and to mount the squeegee blade in a desired location and orientation relative to

the floor being cleaned. The support or back-up strip 16 may be a conventional material, such as rigid

plastic, stiff er than the material of the squeegee blade 15. The purpose of the

support strip is to provide a backing or support in use for the squeegee blade to

maintain the lower working edge of the squeegee blade in proper operating position and orientation relative to the floor, and to reduce deflection of the squeegee blade

under normal use conditions. The support strip 16 is also received on the locating

pins 31 and rear stud 32 by means of a series of apertures 35, and it assumes the

shape of the mounting plate 11 and blade 15. Turning now to FIGS. 1 and 2, the retainer 13 is in the form of an elongated

bar which includes a forward portion 38 welded to a second hinge plate 39 of hinge

14. The hinge plates 26, 39, as will be appreciated, are secured respectively, then

to the transverse forward plate 22 of the intermediate section 27 of the mounting plate 11 by studs 45 and bolts 46, and to the side of forward portion 38 of the

retainer bar 13. The hinge plates 26, 29 are then provided with ferrules, as is

conventional, and rotatably secured together by means of a hinge pin 40 received in

the ferrules. The hinge 14 permits the retainer bar 13 to be rotated, when freed from the mounting plate 11 , between the open or replacement position as shown in

FIGS. 1 and 2, and a closed or secured position, as seen at 54 in FIG. 2, for use.

The retaining bar 13 is shown, for purposes of illustrating its use, in the open or replacement position as seen at 52 in FIG. 2.

The bottom edge of the retaining member 11 may be flared outwardly as at 42

for the forward section 38 of the retaining member, and at 43 for the rear section

41. The flared portions of 42, 43 of the retainer member 11 permit the squeegee

blade to flex when passing over unevenness in the floor being scrubbed, while

securing and adding strength and resistence to both the backup strip 16 and the

squeegee blade 15. The retainer bar both forward and rear sections, is provided with a series of openings 44 aligned with and receiving the locating pins 31 and locating fastener 32

of the mounting plate 11 when the retainer 13 is rotated to the closed position. The

pins 31 also pass through the apertures 44 of the retainer bar 13 to provide vertical

support to mounting plate 11, but they are not fastened or secured to the retainer.

The threaded stud 32 passes through the squeegee blade 15 and the back-up strip

16, and the rear aperture 44 of retainer bar 13. Internally threaded knob 17 is

fastened to the threaded stud 32 to secure the retainer member 13 in the use

position, clamping the support strip 16 and the squeegee 15 to the frame of the machine by means of the mounting plate 11.

Having disclosed one embodiment of the invention, persons skilled in the art

will be able to modify the structure disclosed and to substitute equivalent elements for those illustrated. The combination of the threaded stud 32 fixed to the mounting plate 11 and

the locking knob 17 provide a convenient hand-operable fastener to secure the pivoting retainer 13 to the mounting plate and prevent it from opening. Other

fasteners such as clasps, over-center bales or clips, as well as other devices, could

equally well be used to perform this function of releaseably securing the retainer against opening and clamping the squeegee blade 15 and back-up strip 16 to the

mounting plate 11. Thus, the word "fastener" is intended to be used in its broadest

meaning. Further, the use of the knob 17 with enlarged radial extensions and finger

recesses to facilitate the exertion of leverage by hand is also considered an advantage

and convenience. The term "hand fastener" is intended to include all such fasteners

capable of being opened and secured with the application of normal hand force

without the need for tools. It is thus intended that all such modifications and substitutions be covered as

they are embraced within the spirit and scope of the appended claims.

Claims

WE CLAIM:

1. For use with a floor scrubbing machine having a frame, a side squeegee assembly comprising: a mounting member fixed to said frame adjacent a lateral side of said machine and having a forward portion extending in a direction of forward travel of

said machine, and a rear portion extending rearwardly and inwardly of said

machine when said mounting member is fixed to said frame; a retainer member pivotally mounted to said mounting member for rotation between an open and a closed position, said retainer member conforming

generally to the shape of said mounting member in a horizontal plane; a flexible squeegee blade clamped between said mounting member

and said retainer member; and a hand fastener for releaseably securing said retainer member to said

mounting member.

2. The apparatus of claim 1 further comprising a hinge connecting

forward ends of said mounting member and said retainer member for pivotal

movement between said mounting and retainer members about a generally vertical

hinge axis.

3. The apparatus of claim 2 wherein said hinge includes first and

second hinge plates fixed respectively to said mounting member and to said

retainer member, and a hinge pin journaled respectively to adjacent portions of

said first and second hinge plates and defining said vertical hinge axis.

4. The apparatus of claim 3 further comprising a flange located at a forward edge of said mounting member, first and second studs fixed to said flange and spaced vertically apart, a first one of said hinge plates of said hinge being

fixed to said flange of said mounting member and wherein said first hinge plate includes first and second laterally elongated openings received on said first and

second studs fixed to said flange of said mounting member, whereby said

mounting member and said retainer member are pivotally mounted to one another

while permitting the space for said squeegee member to be adjusted for different widths of said squeegee member.

5. The apparatus of claim 4 further comprising a support strip located

between said retainer member and said squeegee blade for supporting said

squeegee blade in use.

6. The apparatus of claim 1 wherein said squeegee blade is

characterized as having a vertical cross section which is generally rectangular,

thereby defining four corner edges of said squeegee blade, whereby said squeegee

blade includes four separate working edges for said squeegee blade.

7. The apparatus of claim 6 wherein said mounting member is attached

to said frame of said machine at an angle offset to the vertical, such that an inner,

lower edge of said squeegee blade provides a contact working edge for engaging a

floor being scrubbed.

8. The apparatus of claim 1 wherein said hand fastener includes a

threaded stud fixed to said mounting member and extending through said

squeegee blade and said retainer member; and an internally threaded nut received

on said threaded stud, whereby said nut may be manually tightened or loosened

externally of said machine.

9. The apparatus of claim 8 characterized in that said nut member is

internally threaded and includes outwardly flared extensions defining intermediate finger contact recesses for loosening or tightening said fastener and characterized

in that said nut may be loosened or tightened with the application of normal hand

force and without the use of tools.