US2268015A - Floor polisher - Google Patents

Description

D. so, 1941. F E, BROBERG 2,268,015

FLOOR POLISHER l Filed Jan. 3, 1941 2 Sheets-Sheet l i. Z l INVENTOR ATTO RN Ejr.

F. E. BRoBl-:RG

FLOOR POLISHER Filed Jan. 5, 1941 2 sheets-sheet 2 INVENTOR ATTORNEY.

Patented Dec. 30, 1941 2,268,015 FLOOR POLISHER Fred E. Broberg, Racine, Wis., assigner, by mesne assignments, to S. C. Johnson & Son, Inc., Racine, Wis., a corporation of Wisconsin Application January 3, 1941, Serial No. 373,019

13 Claims.

tively light weight, while economical of manufacture, have not thus far been entirely satisfactory.

It is therefore a primary object of my invention to provide an improved light weight polisher of the type employing a brush which rotates about a vertical axis and wherein the brush provides the sole support for the motor and its mounting structure, whereby higher brush speeds than have heretofore been thought practical may be safely employed with a resultant increase in the Work capacity of the device.

A further object of the invention resides in the provision of improved means for the manual control of a high speed polisher of the disk brush type.

More specifically it is an object of this invention to provide a polisher of the single disk type with an improved handle which permits stabilization of the polishing brush during its high speed rotation in contact with surfaces which set up unbalanced torsional stresses within the brush.

A still further object is to provide a handle controlled polisher of the above type with resilient means within the handle to allow relative movement between portions thereof for the absorption of torsional stresses and vibrations which, if unabsorbed, tend to amplify to the extent that the polisher becomes uncontrollable.

And still another object of the invention is to provide a polisher of this type with improved means for pivoting the handle to the polisher frame in a manner whereby said pivotal mounting cooperates with resilient means within the handle to provide stabilization and improved control of the device during use.

A further object is generally to simplify and improve the construction, arrangement and operation of polishers for one or more of the purposes mentioned, and still other objects will be apparent from the specication.

The invention includes the construction and arrangement of parts as herein illustrated, described and claimed and. since various modifications thereof are contemplated, it will be understood that the invention also includes such modifications as are equivalent to the claims.

The same reference characters have been used for the designation of like parts throughout, and in the drawings:

Fig. 1 is a top plan view of a floor polisher.

Fig. 2 is a side elevation of the device shown in Fig. 1.

Fig. 3 is an enlarged sectional view on the line 3-3 of Fig. 1.

Fig. 4 is an enlarged sectional view on the line 4-4 of Fig. 1.

Fig. 5 is a sectional view on the line 5-5 of Fig. 4; and

Fig. 6 is a perspective view of the mounting bracket shown partially cut away in Fig. 4.

As shown in Figures 1 and 2, the device includes a downwardly opening housing or frame I0, a motori II mounted thereon, a disk type rotary brush I2 provided with a rigid brush block I3 and disposed within housing I0, and a shaft I4 carried by block I3, said shaft being suitably journaled for rotation with respect to frame I0 and connected to motor I I through drive mechanisms I8 and Il and reduction units I8 and I9.

A handle, generically designated by reference numeral 23 includes a rigid forked portion 24 having its fork arms pivoted to frame I0 on opposite sides of motor I I as hereinafter described, an elongated rigid portion 25 adapted to be gripped by an operator and a universally yieldable connector 21 between fork 24 and handle portion 25.

As shown in Fig. l, housing I0 is provided with a pair of slots or openings ,28 disposed on opposite sides of the motor to allow extension therethrough of the lower fork arm portions.

As best shown in Figures fl and 5, the end of each fork arm is provided with oir-set portion 30 which carries an insert |30 of hardened material, said insert being provided with a transverse bore through which apintle bolt 3l carried by frame I0 projects to permit pivotal movement of the fork arm through a vertical plane with respect to frame I0. Bolt 3I is carried intermediate a pair of brackets 33 and 34 which are welded to the bottom wall of, housing I0 to depend therefrom. Bolt 3I is provided witha hexagonal head and the depending arm of bracket 33 is provided with a complementary aperture, as best shown in Fig. 6, to receive the bolt head in axially slidable but nonrotatable relation thereto.

A dish-like resilient washer 35 is disposed intermediate the bolt head and the adjacent surface of insert |30 to provide frictional thrust engagement between the fork arm and bracket 34 when clamping pressure is applied to the bolt as hereinafter described. Bolt 3| includes a cylindrical bearing portion 31 on which the fork arm pivots and a reduced portion 38 having a nut 38 in threaded engagement therewith. A washer 40 5 is disposed between bracket 3l and the adjacent side of insert |30. Bearing portion 31 of bolt 3| projects through washer 40 whereby annular shoulder M between bearing portion 31 and reduced portion 38 of bolt 3| abuts bracket 34 to l0 ther tightening of nut 39 does not increase the 20 thrust which washer -35 exerts on the fork arm to provide the desired yieldable frictional engagement between the arm and bracket 3l. It

' is therefore possible to rapidly assemble the structure without trial and error adjustments to v2:5

obtain the exact amount of thrust desired.

Universal connector 21 includes a housing 5l,

threadedly engaging an annular shoulder 5| which may be an integral extension of fork arm 24. Shoulder 5| projects upwardly from a flat- 30 tened upper portion of the fork 2l in a position midway between the fork arms. Housing l is provided with an interior chamber including a cylindrical passageway 53 leading from the outer end thereof into an enlarged cylindrical pas- 35 sageway I which in turn leads into a further enlarged cylindrical portion 55. Elongated handle portion has a cylindrical end section projecting through chamber portions 53 and 5l and into portion 55 to terminate at a point spaced 0 from the ends of said chamber portion. A sleeve 58 is carried by that section of the handle disposed within chamber 4portions 54 and 55. Sleeve 58 is preferably in press fit engagement with handle 25 and may be welded thereto to 45 prevent relative movement between the sleeve and handle. A flange 53 extends radially from sleeve 58 at the handle terminus, said ange being an integral portion of the sleeve. The outer wall of ange 59is in spaced relation tothe in- 50 ner side wall of chamber portion 55, and the periphery of sleeve 58 and handle 25 are in spaced,

relation to the inner walls of chamber portions 54 and 53 respectively, whereby to allow relative movement between the handle and sleeve assem- 55 bly and the housing v5|I.

An annular resilient bumper 80, rectangular in cross section, is disposed between the bottom wall of chamber portion 55and the bottom surface 'of flange 59, and an annular resilient 60 bumper 62 which may be circular in cross section is disposed between the top wall of chamber portion 55 and the top wall of ilange 53. A pin 6| is anchored in the flat portion of fork 2| to project through suitable bores in bumper 50 and 65 flange 59 respectively, whereby to constrain the bumper and flange against rotation relative -to the fork and housing 50.

The mounting of handle portion 25 between and the provision of space between the chamber walls and adjacent portions of the handle and its attached sleeve 58 permits limited movement in all directions between the rigid handle portion resilient bumpers within the chambered housing substantially dampened within the connector to' arrest their effective transmission to the brush. I have found that the device works well when the distribution of weight of the brush and the structure directly supported thereon is such that the horizontal axis about which the forky arm f pivots is preferably' somewhat below the center A housing 18 is removably attached to frame I0 to protect the motor from dust and injury and to add an attractive appearance to the device. A pair of shroud-like guards 1| are mounted to frame I 0 to project marginally from fork arm opening 28, whereby to provide bumper means forl limiting the pivotal movement of the forkv arm. A protective bumper 13, which may be of rubber, encircles the lower margin of frame I8 to'provide cushioning means during contact of the divice in operation with objects such as furniture.

'I'he arms of fork 24 are provided with a passageway 15 which extends from the fiat top portion of the fork to points below the top wall of frame housing I0. A bore 18 leads through shoulder 5| and into passageway 15. A detachable connector plug 11 is partially disposed within the lower end of tubular handle 25 and par# tially disposed within bore 18 and passageway 15, whereby to provide convenient disassembly of the .electrical connections upon removal of housing 58. Bore 16 is of suillcient size to allow substantial space between the walls thereof and the periphery of plug 11, whereby the plug will not bind in respect to oil'set portion 5| during flexing of connector 21. Plug 11 is preferably pinned at 18 to handle member 25 and sleeve 58.

Electrical leads extend through handle 25 and are electrically connected to plug 11 to be divided and separately extended through the fork arms to points below the frame where they are connected by suitable means to motor Il.

Uneven pressures at various parts of the disk brush with respect to the surface to be polished are encountered in the ordinary operation of the polisher by virtue of an uneven floor or as the result of the polisher coming into contact with objects such as furniture or showcases. The torque reaction at the point of increased brush pressure tends to lift the entire polisher at this side and to depress the opposite side of the polisher whereby a corresponding condition of increased unbalanced brush pressure is produced. The action therefore repeats itself with rhythmic regularity and with increasing amplitude until the polisher capsizes.

The above described improvements co-act to prevent an increase in amplitude of said rhythmic vibrations by allowing the brush and the' tions as a shock absorber while the yielding re- 25 and the rigid fork. whereby vibrations and 7 sistance applied to the pivotal connection of the handle fork arms prevents the rhythmic vibra.- tion of the polisher about its horizontal axis. 'The eiect of the cooperation of the yieldingly resistant universal joint with the restricted movement of the polisher about the fork mounting axis provides a polisher of high efiiciency which operates smoothly and which can readily be moved about by the operator. The entire construction is compact and of distinctly improved appearance.

Having thus described the invention, I claim:

l. In a device of the character described, the combination of a frame, a polishing member journaled thereto to rotate about a substantially vertical axis and mounted beneath said frame, a motor mounted on said frame, drive means intermediate the motor and polishing member, and a handle pivotally connected to the frame, said handle comprising a pivoted fork portion, an elongated rigid portion, and resilient universal joint means intermediate the iork and 4elongated handle portions.

2. In a device of the character described, the combination of a frame,A a polishing member journaled thereto to rotate about a substantially vertical axis and mounted beneath said frame, a motor mounted on said frame, drive means intermediate the motor and polishing member, and a handle connected to the frame, said handle comprising a fork portion pivotally engaging said frame in clamping relation lthereto, an elongated' rigid portion, and resilient universal joint means intermediate the fork and elongated handle portions.

3. In a device of thecharacter described, the combination of a frame, a polishing member journaled thereto to rotate about a substantially vertical axis and mounted beneath said frame, a motor mounted on said frame, drive means intermediate the motor and polishing member, and a handle comprising a rigid portion connected to the frame, a second rigid portion extending from said first mentioned portion, and resilient universal joint means intermediate the handle portions.

4. In a device of the character described, a

posite sides of the motor along an axis at right angles to the axis of brush rotation, and clamp means intermediate the frame and fork handle section whereby to yieldingly resist pivotal movement of the handle with respect to the frame.

7. A deviceas described in claim 6 wherein the clamp means includes a pair of bracket arms mounted to the frame, a plntle bolt supported by said arms and pivotally engaging the forked handle section, a spring washer carried by the bolt,' and clamp means carried by the bolt for pressure engagement of the handle section and one of the bracket arms under distortional pressure of the washer, said bolt being provided with a shoulder for engagement with said bracket arm upon a predetermined distortion of said washer whereby to limit the pressure engagement bein which the entire weight of the polisher rests upon the brush, a frame, a. polishing member mounted for horizontal rotation beneath the frame, a motor mounted upon said frame in operative connection with said member, and a handle including a fork and an elongated member, said fork being pivoted to the frame along a horizontal axis extending below the center of mass of the frame, brush and motor, and said elongated member being resiliently mounted on said fork at a point substantially midway between said fork arms, and means to yieldingly resist the pivotal movement of the fork arms .with respect to the frame.

9. A floor polisher including a brush ,iournaled handle adapted to stabilize torsional stresses initiated in the device during operation and comprising a rigid fork provided with a chamber positioned substantially midway Abetween the fork arms, a rigid elongated member having one end loosely disposed within said chamber for relative movement between the fork and elongated member, and means disposed within the chamber for the retention of the end portion of said elongated member therein in resilient engagement with said fork.

5. A device as set forth in claim 4 whereintype brush disposed beneath the frame in bearing relation therewith for rotation about a vertical axis and to provide the sole support for said motor and frame, a handle comprising a forked section and an elongated section and a iiexible connection between the handle sections, said fork section pivotally engaging the frame on opsuperposed relation thereto and supported on the brush, an electric motor mounted on said frame,

drive means connecting the motor to the brush for the rotation thereof, a handle comprising a.`

lower forked tubular section and an upper elongated tubular section, said lower section being pivoted to the frame, and said upper section being connected therewith through a resilient universal joint, -a chamber extending centrally through said universal joint and connecting said tubular sections to provide a passageway throughout the handle, electrical connections extending through said passageway and connected to said motor, said connections including a detachable plug mounted in said passageway and having a. portion attached to said upper section and a portion 'projecting into said chamber in spaced relation to the walls thereof whereby to prevent engagement between the plug and the chamber walls during flexing pf said universal joint.

l0. In a device of the character described, a frame, a pair oi.' brackets mounted thereto, a plntle bolt supported by said brackets, and a handle disposed between the brackets in pivotal engagement with the bolt, said bolt including a at sided head, a cylindrical bearing portion and a reduced threaded portion to provide a shoulder therebetween, one of said brackets being pro-V vided with an aperture complementary to saidfiat sided bolt head, said head being disposed therein in axially slidable and nonrotatable relation thereto, the other bracket being provided with a bore through which said reduced portion projects, a thrust washer carried by said bolt intermediate one of the brackets and the handle, and a nut threadedly engaging said reduced portion for the limited clamping engagement of the handle as predetermined by the shoulder on the bolt.

11. A floor polisher comprising a frame, a poiishing member rotatably mounted on the frame, a motor carried by the frame and in operative driving connection with the member) and a handle for said frame comprising a first section in pivotal connection with the frame and a second section universally connected to the rst section, together with resilient means opposing relative universal movement between said sections.

12. A floor polisher comprising the combination with a rotary polishing brush, of a motor support having bearings for said brush and havlng its weight carried by said brush, a motor on l5 said support in operative driving connection with r said brush, and a guiding handle for said polisher comprising a plurality of universally jointed sections, one of which is pivotally connected to said support, said handle having an elastic centering means mounted on one of said sections and engaging the other to resist universal movement therebetween.

13. A motor driven iloor polisher comprising the combination with a rotatable polishing brush,

a motor support carried by said brush and hav-

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