US3639936A

US3639936A - Self-propelled floor scrubber

Info

Publication number: US3639936A
Application number: US44168A
Authority: US
Inventors: Walter G Ashton
Original assignee: STAR IND Inc
Current assignee: STAR IND Inc
Priority date: 1970-06-08
Filing date: 1970-06-08
Publication date: 1972-02-08
Anticipated expiration: 1989-02-08
Also published as: DE2034813A1; SE364866B; NL145753B; FR2094097A1; GB1322240A; FR2094097B1; NO128472B; NL7010151A

Abstract

A hydraulic motor-propelled occupant-driven floor scrubber having a subframe supporting structure for rotating brushes and squeegee assemblies that are each independently hydraulically movable into and out of operating floor-engaging position, with each of the subframe structures having floating shock-absorbing arrangements.

Description

O United States Patent 1151 3,639,936 Ashton [4 1 Feb. 8, 1972 [54] SELF -PROPELLED FLOOR SCRUBBER [56] References Cited [72] Inventor: Walter G. Ashton, Winnetka, lll. UNITED STATES PATENTS [73] Assignee: Star Industries, Inc., Chicago, Ill, 3,376,597 4/1968 Boyd 15/320 Filed: June 8, 1970 Primary Examiner-Leon G. Machlin [2' 1 App]. No: 44,168 Attorney-Edward C. Threedy [57] ABSTRACT [52] [1.8. CI A h d li t o ned o upanpdriven floor crubber [5|] Int. Cl. ..A47l 11/29 havi g a ubframe supporting structure for rotating brushes [58] Field of Search ..l5/4, 49 R, 50, 87, 340, 320, and squeegee assemblies that are each independently hydraul5/3l9 lically movable into and out of operating floor-engaging position, with each of the subframe structures having floating shock-absorbing arrangements.

' 8 Claims, 6 Drawing Figures PATENTEIJ FEB 8l972 3 639936 sum 2 or 3 1/871 Tram/.

SELF-PROPELLED FLOOR SCRUBBER SUMMARY OF THE INVENTION A self-propelled floor scrubber which includes a tractor unit having an internal combustion engine which operates an alternator as an electrical power source and a pump for pressurizing the hydraulic system which in turn operates the hydraulic brush-rotating motors as well as a hydraulic drive motor for propulsion of the tractor unit.

The rotating brush assembly provides three circular flat-tothe-floor brushes arranged in a triangular pattern, and is pivotally connected to the under frame of the tractor unit and operatively connected to a movable piston of a hydraulic cylinder which functions to pivotally raise and lower the brush assembly.

The squeegee assembly consists of a parallelogram arrangement which, through the operation of a hydraulic cylinder, is pivotally associated so as to raise and lower the squeegee elements into and out of floor-engaging position.

The hydraulic system also includes an automatic bypass conduit arrangement whereby when the tractor unit is propelled in a reverse direction, the squeegee assembly will be automatically raised so as to prevent damage thereto and to permit continuing the scrubbing operation of the rotating brushes in either forward or reverse direction.

GENERAL DESCRIPTION The invention will be best understood by reference to the accompanying drawings, in which:

FIG. 1 illustrates a self-propelled floor scrubber unit;

FIG. 2 is a perspective view of the squeegee subassembly;

FIG. 3 is a perspective view of the brush subassembly;

FIG. 4 is a perspective side view of the brush subassembly;

FIG. 5 is a fragmentary detailed sectional view of a shockabsorbing connection associated with the squeegee subassembly;

FIG. 6 is a schematic flow chart of the hydraulic system employed in the floor scrubber unit.

As illustrated in FIG. 1, the self-propelled floor-scrubbing unit includes a plurality of rotatable floor brushes positioned forwardly and beneath the main frame portion of the tractor unit. The floor scrubber includes a squeegee assembly which positions a first squeegee forwardly of the rear driving wheels of the tractor unit, and a second squeegee to the rear thereof.

Referring to FIGS. 3 and 4, the brush-supporting assemblies comprise a substantially T-shaped subframe 10, with the leg portion thereof comprising two spaced-apart members 11 and 12 formed to converge at their free ends to support a hydraulic brush-rotating motor 13 for the forward scrubbing brush. The opposite ends of the members 11 and 12 are fixedly connected to the crossbar 14 of the T-shaped subframe which in turn at its extremities supports additional hydraulic brushrotating motors l5 and 16.

Extending between the spaced members 11 and 12 of the T- shaped subframe is a connector plate 17, the ends of which are connected as at 18 to each of the spaced members 11 and 12. Mounted on the connector plate 17 by a loose connection 19, is a concaved cambered beam 20. The beam 20 is of a length greater than the connecting plate 17 so as to extend beyond the ends thereof as well as beyond the spaced members 11 and 12.

Fixedly connected to the cambered beam 20 are a pair of supporting

bars

21 and 22 which at their free ends provide a right-

angled portion

23 and 24 which in turn terminates into

leg portions

25 and 26 extending substantially parallel to their respective supporting

bars

21 and 22 and which in turn are pivotally connected as at 27 to the under frame of the tractor unit as seen in FIG. 1.

From the foregoing description, it is obvious that the limited connection between the brush-supporting T-frame and the supporting

bars

21 and 22 is the loose connection 19 between the connector plate 17 and cambered beam 20. Thus, the cambered beam 20 is rockable throughout its longitudinal length upon the connector plate 17, and consequently the brushes mounted on the ends of the crossbar 14 may float over the floor irregularities or obstructions.

At the ends of the cambered beam 20 and extending vertically therefrom are a pair of connecting

rods

28 and 29. As shown in FIG. 4, the connecting rod 28 is in turn connected to an Lshaped link 30 which at a point 31 is likewise pivotally connected to the under frame of the tractor unit. One end of the L-shaped link 30 has connected thereto as at 32, the exposed end of a piston 33 of a hydraulic cylinder 33'. The rod 29 has its free end connected to a pivot bar 34 which is pivotally connected at a point 35 to the under frame of the tractor unit.

The supporting

rods

28 and 29 are journaled through a pair of spring members 36 which have one end bearing against the cambered beam 20 and their opposite ends restrained by a looped end 37. These spring members 36 act as a shock-absorbing connection between the entire brush-supporting T- shaped subframe and the tractor unit.

When the piston 33 is expelled under hydraulic pressure, out of its cylinder 33, it will effect pivoting of the link 30 in a clockwise direction, as seen in FIG. 4, which in turn through the associated structure hereinbefore described, will effect pivoting of the supporting

bars

21 and 22 in anticlockwise direction, as shown in FIG. 4, about their pivotal connection to the under frame of the tractor unit, which pivotal movement in turn will raise the T-shaped brush-supporting subframe, thus raising the brushes out of floor-engaging position.

Depending from the supporting

bars

21 and 22 are guide fingers 38 which bear against the inside surfaces of the spaced members 11 and 12, guiding the movement thereof upwardly as the assembly is pivotally actuated. The member 11 also carries a guide 39 and bumper 40 which prevents over pivotal movement of the T-frame relative to the supporting

bars

21 and 22.

Referring to FIG. 2, the squeegee assembly 41 comprises a pair of parallelogram structures each of which includes an upper fixed supporting bar 42 and a parallel squeegee-supporting bar 43, connected to the supporting bar 42 by parallel side bars 44 and 45. Each of the supporting bars 42 is connected to the underframe of the tractor unit so as to be stationary with respect thereto. The connection of the side bars 45 to the supporting bars 42 includes a shaft 46 upon which is freely journaled by a U-shaped bracket 47, a hydraulic cylinder 48 having a piston 49, the free end of which by a U- shaped bracket 50 is connected to a second shaft 51 which extends between and forms a part of the pivotal connection between the opposite ends of the side bars 44 and the support bars 43.

It is readily apparent that when the hydraulic cylinder 48 is actuated to expel its piston 49, it will collapse the parallelogram structure by effectively pivoting forwardly and upwardly the supporting bars 43, raising the squeegee carried thereby out of floor-engaging position. v

The squeegee-supporting bars 43 are comprised of two

bar members

52 and 53, with the bar 52 terminating at its point of pivotal connection of the side bars 45 thereto, as shown in FIG. 2.

The bar 52 extends forwardly beyond its pivotal connection to the side bar 44 and supports the forward squeegee-carrying bar 52'. The bar 53 extends rearwardly beyond its pivotal connection to the side bar 45 and supports the squeegee-carrying bar 53'. As shown in FIG. 5, the two

bars

52 and 53 are connected to the lower end of the side bars 45 by a nut and bolt arrangement 54 which extends through an elongated slot 55 formed in the bar 53 and through a close tolerance opening 56 in the end of the bar 52. The end of the bar 52 provides a perpendicular rod 57 which is freely journaled through a flange 58 provided by the bar 53. Over the rod 57 is a coil spring 59 which is compressed against the flange 58 by a retaining nut and washer 60. By this arrangement, the bar 53 has a loose connection to the end of the bar 52 as well as to the end of the side bar 45. This loose connection permits a floating shock-absorbing connection of the rear squeegee to its support to accommodate any unevenness in the floor surface being treated by the floor scrubber.

To regulate the length of movement of the piston 49 and thus the relative spacing between the fixed supporting bars 42 and squeegee-supporting bars 43, there is provided a pair of adjusting rods 61 that extend between shafts 46 and 51. These adjusting rods 61 comprise telescoping elements (not shown) that have their opposite ends joumaled onto the shafts 46 and 51. One of the telescoping elements is threaded and carries adjusting nuts 62 which by threadable adjustment determine the overall length of the rods 61.

Referring to FIG. 6, there is schematically shown a hydraulic fiow chart utilized in the floor-scrubbing unit. The system includes a hydraulic pump 63, an engine-cooled heat exchange 64, and a large oil reservoir 65. A flow divider 66 directs the hydraulic fluid to the tractor drive valve and the control valves for the brush and squeegee assemblies. As shown, the fluid from the flow divider is by the conduit 67 passed into the tractor drive valve 68, which in its forward drive position is connected by conduit 69 to the hydraulic tractor drive motor 70. A return conduit 71 is connected to the relief valve 72 and back to the lines of conduit that terminate at the reservoir 65. When the tractor drive valve 68 is actuated so as to drive the unit in a reverse direction, the tractor drive valve 68 is connected by conduit 73 to the reverse flow direction of the tractor drive motor 70. If, however, in the reverse direction the squeegee cylinder 48 through its control valve lever 74 is operated so that the squeegee assembly is in a down position, the hydraulic fluid flowing through the tractor drive valve 68 and conduit 73 is permitted to pass through conduit 75 and directional check valve 76 into the cylinder 48 so as to expel the piston 49 thereof, raising the squeegee assembly before the tractor drive motor 70 moves the unit in a reverse direction.

If the squeegee valve lever 74 is operated so as to open the squeegee valve contained in the valve control unit 77, the hydraulic fluid passes through conduit 78, through the relief valve 72, and into the squeegee cylinder 48, retracting the piston 49 thereof, which in effect lowers the squeegee assembly into its floor-engaging operative position.

When the brush assembly valve lever 79 is actuated so as to lower the brush assembly, it will also function to actuate the

hydraulic brush motors

13, and 16. This is accomplished by having the hydraulic fluid introduced into conduit 80 which is in series connection to the three brush motors l3, l5 and 16, conduit 81 which introduces fluid into the brush assembly cylinder 82, retracting its piston so that the brush assembly unit is lowered onto the floor, through a brush pressure relief valve 83, conduit 84, and back to the reservoir 65. When the brush control valve lever 79 is moved so as to raise the brush assembly, the hydraulic fluid is caused to pass through conduit 85 and into the brush assembly cylinder 82, expelling the piston thereof and pivotally raising the brush assembly out of operative position.

From the foregoing it is apparent that l have provided a direct-drive hydraulic system for propelling the tractor unit as well as for individually controlling the position and operation of the rotatable brushes and their supporting assemblies, as well as the squeegee assemblies. The floating shock-absorbing brush and squeegee assemblies permit the unit to be operated in either a forward or reverse direction, with the squeegee assembly being automatically raised when the tractor unit is in reverse.

While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A self-propelled floor-scrubbing machine including a tractor-type wheeled hydraulically driven body, carrying scrubbing brush and squeegee assemblies, wherein the improvement comprises:

a. a scrubbing brush supporting subframe mounted beneath the forward end of the tractor body,

b. a pivotal support for said subframe including a pair of elongated supporting arms having one end pivotally connected to the tractor body and their opposite ends connected to a concaved cambered crossbeam,

c. means mounting said brush supporting subframe to said cambered crossbeam of said pivotal support for tiltable movement of said subframe relative to said crossbeam and transversely to the long axis ofsaid supporting arms,

d. means providing shock-absorbing connections between the ends of said crossbeam of said pivotal support and the body of the tractor,

c. a hydraulically operated pivoting link pivotally connected to the tractor body at a point removed from and in substantial horizontal alignment with the pivotal connection of said supporting arms of said pivotal support to the tractor body and to said shock-absorbing connections for raising and lowering said brush-supporting subframe relative to the tractor body, hydraulic means for pivoting said link relative to its connection to the tractor body for pivoting said supporting arms relative to their connection to the tractor body for raising and lowering said brush-supporting frame,

g. a squeegee subframe connected to the tractor body between certain wheels thereof, said squeegee subframe including a pair of four-bar mechanisms pivotally joined together in the form of a parallelogram with certain of said bars of each mechanism fixedly connected to the underside of the tractor body and certain other of said bars supporting squeegee elements, and

h. hydraulic means for pivotally collapsing and extending the parallelogram formed by said mechanisms to raise and lower said squeegee elements relative to the tractor body.

2. The floor-scrubbing machine defined by claim 1 including a hydraulic system having manually operated valves for controlling the direction of operation of all of said hydraulic means so as to raise or lower said brush-supporting subframe and said squeegee subframe, said system including a directional hydraulic bypass relative to the control valve for said squeegee subframe adapted to operate said squeegee subframe hydraulic means in one direction so as to raise said squeegee subframe when the scrubbing machine is hydraulically driven in a reverse direction.

3. A self-propelled floor-scrubbing machine as defined by claim 1 wherein said scrubbing brush-supporting subframe is substantially T -shaped, with the extremities terminating in front of and to either side of the tractor body, said T-shaped subframe providing a supporting plate extending in a plane normal to said cambered crossbeam and having a loose connection thereto so as to have a limited tiltable movement through the length of said cambered crossbeam to permit the extremities of said T-shaped subframe at either side of the tractor body to ride upon an uneven floor surface.

4. A self-propelled floor-scrubbing machine as defined by claim 3 including a hydraulic system having manually operated valves for controlling the direction of operation of all of said hydraulic means so as to raise or lower said brush-supporting subframe and said squeegee subframe, said system including a directional hydraulic bypass relative to the control valve for said squeegee subframe, adapted to operate said squeegee subframe hydraulic means in one direction so as to raise said squeegee subframe when the scrubbing machine is hydraulically driven in a reverse direction.

5. A self-propelled floor-scrubbing machine as defined in claim 1 where in the squeegee element supporting bars of said squeegee subframe comprise separated elongated members, the end of one of which is loosely connected and spring resisted to the other elongated member so as to provide a shock absorber between the squeegee subframe and the tractor body.

6. A self-propelled floor-scrubbing machine as defined by claim 5 including a hydraulic system having manually operated valves for controlling the direction of operation of all of said hydraulic means so as to raise or lower said brush-supporting subframe and said squeegee subframe, and said system including a directional hydraulic bypass relative to the control valve for said squeegee subframe adapted to operate said squeegee subframe hydraulic means in one direction so as to raise said squeegee subframe when the scrubbing machine is hydraulically driven in a reverse direction.

7. A self-propelled floor-scrubbing machine as defined by claim 3 wherein the squeegee element supporting bars of said squeegee subframe comprise separated elongated members, the end of one of which is loosely connected and spring resisted to the other elongated member so as to provide a shock absorber between the squeegee subframe and the tractor body.

8. A self-propelled floor-scrubbing machine as defined by claim 4 wherein the squeegee element supporting bars of said squeegee subframe comprise separated elongated members, the end of one of which is loosely connected and spring resisted to the other elongated member so as to provide a shock absorber between the squeegee subframe and the tractor body.

Claims

1. A self-propelled floor-scrubbing machine including a tractortype wheeled hydraulically driven body, carrying scrubbing brush and squeegee assemblies, wherein the improvement comprises: a. a scrubbing brush supporting subframe mounted beneath the forward end of the tractor body, b. a pivotal support for said subframe including a pair of elongated supporting arms having one end pivotally connected to the tractor body and their opposite ends connected to a concaved cambered crossbeam, c. means mounting said brush supporting subframe to said cambered crossbeam of said pivotal support for tiltable movement of said subframe relative to said crossbeam and transversely to the long axis of said supporting arms, d. means providing shock-absorbing connections between the ends of said crossbeam of said pivotal support and the body of the tractor, e. a hydraulically operated pivoting link pivotally connected to the tractor body at a point removed from and in substantial horizontal alignment with the pivotal connection of said supporting arms of said pivotal support to the tractor body and to said shock-absorbing connections for raising and lowering said brush-supporting subframe relative to the tractor body, f. hydraulic means for pivoting said link relative to its connection to the tractor body for pivoting said supporting arms relative to their connection to the tractor body for raising and lowering said brush-supporting frame, g. a squeegee subframe connected to the tractor body between certain wheels thereof, said squeegee subframe including a pair of four-bar mechanisms pivotally joined together in the form of a parallelogram with certain of said bars of each mechanism fixedly connected to the underside of the tractor body and certain other of said bars supporting squeegee elements, and h. hydraulic means for pivotally collapsing and extending the parallelogram formed by said mechanisms to raise and lower said squeegee elements relative to the tractor body.

3. A self-propelled floor-scrubbing machine as defined by claim 1 wherein said scrubbing brush-supporting subframe is substantially T-shaped, with the extremities terminating in front of and to either side of the tractor body, said T-shaped subframe providing a supporting plate extending in a plane normal to said cambered crossbeam and having a loose connection thereto so as to have a limited tiltable movement through the length Of said cambered crossbeam to permit the extremities of said T-shaped subframe at either side of the tractor body to ride upon an uneven floor surface.