US2917760A - Electric hand drill powered floor polisher - Google Patents

Description

Dec. 22, 1959 J. c. BAXTER 2,917,760

ELECTRIC HAND DRILL POWERED FLOOR POLISHER 2 Sheets-Sheet 1 Filed Oct. 30. 1957 26 26 28 22 200 24 I5 45 2| 24 20 200 INVENTOR 0 JOHN CHARLES BAXTER F/ BY ATTORNEYS Dec, 22, 1959 J. c. BAXTER 2,917,750

ELECTRIC HAND DRILL POWERED FLOOR POLISHER Filed on. so, 1957 2 Sheets-Sheet 2 INVENTOR.

4 JOHN CHARLES BAXTER A1 TORNEYS United States atent ELECTRIC HAND DRILL POWERED FLOOR POLISHER John Charles Baxter, Harmondsworth, England, assignor to The Black and Decker Manufacturing Company, Towson, Md., a corporation of Maryland Application October 30, 1957, Serial No. 693,357

Claims priority, application Great Britain November 12, 1956 6 Claims. (Cl. 15-49) The instant invention relates generally to the floor polishing art and machines for floor polishing, and more particularly to an attachment for use with a portable hand type power unit, such as is available in a hand electric drill, to provide by the resulting combination a powered floor polishing machine.

Currently the prevalence of portable hand power tools, particularly electric drills, not only in commercial mechanic shops but especially in a great number of households, afiords a power unit whence motive power may be derived for many operations otherwise performed by hand. Hence accessories or attachments, in kind varied as the manual operations replaced thereby-for example, hedge trimmers, liquid agitators, sandershave been proposed and used with such units.

It is the principal object of the present invention to provide a device, for use in conjunction with a relatively small, rotary output power unitsuch as an electric drill or the like, which is adapted for polishing, buffing or like operations; thus adapted for buffing waxed or polished floors, for spreading certain types of polishes or waxes, or even for scrubbing or otherwise cleaning extended surfaces. Another object is the provision of an attachment of the general character described which is adapted for use in cleaning, bufiing or polishing floors or like extended surfaces in the average home. Another object is to provide an attachment of the character described of simple durable construction. A still further object is the provision of a combination with a power unit, such as a portable electric drill or the like, of an accessory which results in a relatively low cost implement effective for polishing and like operations of the character described.

Other objects and advantages will appear from the following description and the drawings wherein:

'Fig. 1 represents one embodiment of the invention, with the attachment viewed from the right side and partly in section, taken irregularly substantially as indicated by the line l-l in Fig. 2;

Fig. 2 is a top plan view;

Fig. 3 is a bottom view corresponding to Fig. 2; and Fig. 4 is a side view of a bumng pad adapted for use with the attachment.

As best seen in Fig. l of the drawings, the combination implement contemplated by the present invention comprises a power unit such as the electric hand drill D and the separable attachment A; the attachment including a frame or housing F, mounting an identical pair of rotatable annular brushes B and a stationary brush S which are in operational and implement supporting contact with a floor to be polished or like surface, and a handle H projecting upwardly from the frame, to curve at its upper end into an apt form providing a hand grip at a suitable height and disposition for the operator.

The housing for frame F is a hollow downwardly open shell readily produced as a single metal casting, roughly "an elongated-oval in plan form, having an upwardly externally convexor-domed form at thetop wall and ice having a dependent continuous downward flange or skirt 11 carrying a correspondingly shaped buffer element 12. It may be noted that in addition to the integral formations of the housing herein described, the inner hollow of the housing member may be provided with internal reinforcing ribs in accordance with common design practice. The element 12 is formed of rubber or other similar resilient material suitable both to prevent damage to objects bumped by the implement in use, and to retain the buffer element 12 on the frame by resilient frictional engagement of the bottom outwardly headed edge of the skirt 11 in an upwardly open channel or slot of the buffer element. Preferably the buffer element is molded in closed curve form. In similar manner, the elongated stationary brush element S is supported inboard of skirt 11 at the rear of the frame to extend transversely at the midline of the same and overlap the gap between rotary brushes B, by reception of the brush base in a corresponding downward channel or slot in buffer 12.

Within the confines of skirt 11, a pair of oppositely rotating meshed brush supporting gears 14, for respective brushes B, are mounted for rotation about vertical axes by corresponding brush spindles 15 extending through sleeve hearings or bushings 16 press fitted into the gear hubs. The reduced upper ends of the spindles, or opposite handed threads, are secured in appropriately threaded formations 17 disposed along the transverse major axis of the housing in the underside of the dome. The hand of the respective spindle thread is of course chosen for tightening under the contemplated driving direction. Thrust washers 13 are interposed between the housing formations 17 and the flanged upper ends of bushings 16, and the headed lower ends of the spindles in engaging the bottom ends of the bushings retain the gears in place. To the end face of the downwardly pro ecting hub 20 of each gear, a shallow cup-like bridge piece 21, readily formed of sheet metal, is secured by screws 22 passed through diametrically disposed bridge ears and threaded into the respective radial hub projections 20a. An oil retaining washer 24, a felt ring or the like projecting 'into a gear hub end groove ad acent the bushing, is retained by the bridge 21. An oil injection aperture may be conveniently formed in the bridge cup and in the region of the oil retainer. i

Each brush unit B includes a generally disk-like base 26 from the bottom face of which project the bristles in annular array, the particular manner in which the base and bristles are unitarily assembled being no part of the invention. The bottom face of each brush gear is recessed to form a dependent circumferential flange 27 embracing in slip-fitted relation the periphery of the brush base disk. The center of the brush base is centrally apertured to receive the hub 29 with its radial lugs or arms 29:1 projecting for driving engagement into broad notches in the brush aperture, the brush being retained by a pair of spring brush clips 28 held by screws 22 on the hub and extending out under adjacent parts of the base.

At the front of the dome of frame F an integral vertical tubular formation 39, furnished with a bottom flanged sleeve bearing 31 press-fitted therein, journals an input spindle or shaft 32 carrying a pinion 33 meshed with the right brush gear. The axis of the tubular formation accordingly is disposed slightly to the right of the longitudinal center line of the frame, as well as forward of the transverse centerline at which the brush gears mesh, so that the pinion clears the left gear. A snap ring 35, engaged in an external groove in the projecting upper end of shaft 32, and an underlying thrust washer 36 resting on the end of bushing 31 support vertically the pinion and its shaft.

'The upper end of the input shaft is formed-to receive a drill adapting driving connector 38. As here shown, the upper end of the input shaft is axially drilled and broached to produce a deep h xagonal socket for reception of one end of the connector 38 formed of hexagonal steel stock and securely chucked in the chuck of drill D.

At the rear center of the housing there is provided a second tubular formation 40 to serve as a socket receiving the lower vertically disposed end of the handle H. The latter is here shown as a tubular element generally vertically disposed, but with top end bent rearwardly to form a hand grip portion 41. Preferably, for storage convenience, the handle is detachably non-rotatably secured in socket 40 by the pin of a suitable releasable lock spring means 44 or the like. A sleeve 4-2, aptly of some rubber-like resilient material, is located on the handle H at a position where a part of the drill or like power unit is expected to come into reaction contact with the handle, thereby to minimize noise and wear arising by contact between handle and drill.

The stationary brush S not only furnishes a iixed element in contact with the surface aiding operator manipulation of the attachment by the handle but also bridges the mid-space of the rotary brush path of translation across a surface.

An underguard or coverplate 43 may be secured as shown in Fig. 1 by screws or the like to dependent housing rib or wall formations, with suitable apertures for projection of the brushes B therethrough. With the outer edge of such guard making a sealing contact with the inner periphery of the resilient buffer 12, and the inner edges close to the brushes, entrance of debris to the mechanism is minimized.

With the male element 45, of a snap button fastener of the type known by the commercial name Durable Dot fastener, affixed at the center of the bridge 21, a round wool hide buffing pad P (Fig. 4) with a corresponding female snap element 46 carried by a webbing stitched on the pad back is readily applied and removed from the attachment, the brush bristles frictionally engaging the pad hide back providing driving engagement for the pad.

Less desirably, from the viewpoint of handling in operation and particularly of required manufacturing precision and tolerances in location of the input and brush gear spindles, the input pinion may be centrally located to mesh with both of the brush gears, the latter then not being mutually meshed since driven to turn in the same rotational sense, and the hand of the spindle threads being chosen accordingly.

With the deep hexagonal socket receiving a corresponding portion of the connector 38 in preferably close slip-fitted relation and the connector inserted to full depth of the drill chuck, the drill is vertically supported entirely by the input spindle and while being held against rotation under operating conditions by contact of a part of the drill, as the ordinary drill handle structure, with handle H. This method of mounting the drill on the attachment obviously affords a quick manner of assembly of the two principal parts of the powered polishing combination device.

Where a power unit has normal operating speeds of say 1800-2000 r.p.m., a 4 to 1 reduction is well used in the pinion-gear combination. The stabilizer brush 8 counteracts any tendency of the apparatus as a whole to spin about on the floor surface while running but not grasped by the operator.

I claim:

1. The combination with a hand portable electric drill or the like power unit having a rotationally driven output member, of a floor polishing attachment comprising: a transversely elongated housing having a top and a dependent peripheral skirt portion, a pair of brush supporting gear members supported from the top of and within said housing for rotation about vertical axes lying in a plane transverse of said housing, a vertical input spindle rotatably supported in the top of said housing and the top of said housing having an upward opening providing endwise access to the spindle from above, said input spindle being disposed in the mid-region of and near the front of said housing, a pinion member on said spindle within the housing meshing with at least one of said gear members, the other of said gear members meshing with one of said members whereby rotary motion of said spindle is communicated to said gear members, a pair of rotary brush elements each secured in driven relation to a bottom face of a respective gear member and each having a bristle array projecting downwardly beyond the skirt portion of the housing, a manipuiating handle member extending upwardly from and fixed to the rear portion of said housing, and a driving connection means operatively detachably engaged in axial alignment between said output member and spindle, said connecting means providing a sole vertical support of said unit with respect to said attachment and said handle member providing a torque reaction abutment for engaging and holding the casing of said unit against rotation during transmission of motion from said output member to said spindle.

2. For use in combination with a hand portable electric drill or the like power unit having a rotationally driven output member and a handle portion extending away from the axis of rotation of said member, a floor polishing attachment comprising: a transversely elongated housing having a top and dependent peripheral skirt portion, a pair of brush supporting gear members supported from the top of and within said housing for rotation about vertical axes lying in a plane transverse of said housing, a vertical input spindle rotatably supported in the top of said housing and projecting vertically therefrom, said input spindle being disposed in the mid-region of and near the front of said housing, a pinion member on said spindle within the housing meshing with at least one of said gear members and the other of said gear members meshing with one of said members whereby rotary motion of said spindle is communicated to the gear members, a pair of rotary brush elements each secured in driven relation to a bottom face of a respective gear member and each having a bristle array projecting beyond the skirt portion of the housing, driving connection means operatively detachably engaged in, and in axial alignment between, said output mem oer and spindle, said connecting means providing a sole vertical support of said unit with respect to said attachment, and a manipulating handle member extending upwardly from said housing into a location to be encountered by the said handle portion for providing torque reaction for said unit.

3. For use in combination with a hand portable electric drill or the like power unit having a rotationally driven output member and also having a casing with a handle portion extending outwardly from the direction of the rotational axis of said member, a floor polishing attachment comprising: a transversely elongated housing having a top and dependent peripheral skirt portion, a pair of meshed brush supporting gear members supported from the top of and within said housing for rotation about vertical axes lying in a plane transverse of said housing, a vertical input spindle rotatably supported in the top of said housing and projecting vertically therefrom, said input spindle being disposed near to and to one side of the center of and near the front of said housing, a pinion on said spindle within the housing meshing with but one of said gear members, a pair of rotary brush elements each secured in driven relation to a bottom face of a respective gear member and each having a bristle array projecting downwardly beyond the skirt portion of the housing, driving connection means operatively detachably engaged in axial alignment between said output member and spindle, said connecting means providing vertical support of said unit with respect to said housing, and an abutment member secured in, and extending upwardly from the rear portion of, said housing for engaging a handle portion of a said unit to serve as a torque reaction member by restraining rotation of the unit casing.

4. A device as set forth in claim 3 including a stationary brush element depending below the center rear portion of said skirt and extending parallel to said plane.

5. A device as set forth in claim 3 wherein said reaction member is provided by a manipulating handle member.

6. A device as set forth in claim 3 wherein said connecting means is comprised of an elongated member with an upper end adapted for driving engagement in a drill chuck and with a lower end length of non-circular crosssection, and said spindle is provided with a socket adapted to receive said lower end length in driving relation.

References Cited in the file of this patent UNITED STATES PATENTS 589,506 Kimball Sept. 7, 1897 1,694,738 Geary Dec. 11, 1928 2,007,073 Clarke July 2, 1935 2,140,307 Belaschk et a1. Dec. 13, 1938 2,220,224 Faber Nov. 5, 1940 2,819,478 Sutton Jan. 14, 1958 FOREIGN PATENTS 1,058,048 France Nov. 4, 1953

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