US1905296A - Floor sander - Google Patents

Description

April 25, 1933- H, w. I UNDQUls-r 1,905,296

FLOOR SANDER Filed July 26, 1929 2 Sheets-Sheet l I N I/ E N TOR #EMDR/eff il( aww/sr A TTORNE Y April 25, 1933- H. w. LUNDQUIST 1,905,296

FLOOR SANDER Filed July 26, 1929 2 sheets-Sheet 2 1N VENTO/e HENDR/c/f IL/ La/vDQz//sr ATTORNEY Patented Apr. 25, 1933 UNrrED STATES PATENT" oFFl CE y FLOORv SANDER;

Application me@ s111526,

VMy invention relates to-fsanding machines and more particularly to portable machines for sanding oors of buildings.

The objects of my present invention are:

5 first, to provide a floor sander in which the chatter, usually present in other sanders and causing the sanding drum to jump up and down while using the same, is reduced toY a minimum thereby ,causing smooth operation l@ of the machine over the Hoor, reducing the time of making a smooth fiat finished surface Von the floor and substantially eliminating furrows, waves, or grooves inthe finished iioor; second, to provide a machine of 15 this class in which the driving mechanism is so arranged that the belts or chains will not be slackenedas the sanding drum is'raised or lowered from the iloorand also a machine of Y this class in which all of the chains or belts 2G can be readily tightened if and when desired; third, to provide an attachment for sanding machines of this class whereby the above mentioned features may be applied to sanding machines now in use and whereby the above named disadvantages may be eliminated therein; fourth, to provide a novel dust pan arrangement in connection with a sander of this class whereby the greater portion of the dust may bedirected into the pan and whereby the pan may be raised and lowered with the sanding drum; fifth, to provide a novel hood arrangement for a sander of this class whereby the hood may be readily raised so that the sanding drum may be readily accessible at all times,-par ticularly for changing the sanding paper or other abrasive material on the drum; sixth, to provide a novelly constructed sanding drum; and, seventh, to provide a machine of this class and attachments therefor which are simple and economical of construction, durable, efficient and which will not readily deteriorate or get out of order. y

.With theseand other objects in view, as D will appear hereinafter, my invention conrsists of certain novel features of construction, combination and arrangement of parts and portions, as will be hereinafter de-l scribed in detail and particularly set forth in the appended claims, reference being had i929. seriaino. 381,196.

to the accompanying drawings `and to the characters of referencethereon which form a part of this application in which:V

Figure l is a fragmentary top `view of my sanding machine in its preferred form of 55 construction, certain parts being broken away to ,facilitate the illustration; Fig. 2 is a fragmentary side elevational View thereof; Fig. 3 is a fragmentary top view thereofon an enlarged scale and partly in section; 00 Fig. 4 is a topview ofthe dust hood of my* machine andthe supportingvmeans therefor; Fig. 5 is a fragmentary sectional viewv of my machine taken through 5 5 of Fig. Vl showing particularly the stationary dust 55 pipe,-the dust hood, .and also the supporting portion thereof lin relation to the frame; Fig. 6 isia fragmentary perspective view showing fragmentarily the supporting arms and shiftable dust pan andtheir supporting meanspand relation tothe main frame and the inlet end of the dust conductor; Fig. 7 is a fragmentarytransverse-'sectional view of the kdrum incorporating my invention; Fig. 8 is a fragmentary side elevational view 75' of a slightly modified form of construction, showing a V-belt drive; and Fig. 9 is a fragmentary front elevational view of the modified construction. Like characters of reference refer to similar parts and portions throughout the views of the drawings.

The machine is carried on a main frame 1 which is supported near its forward portions and at its opposite sides by wheels 2 mounted 'on non-rotatable axles secured Vto the frame 1 and at its rear end by a caster 3, and is directed from place to placel by an Iinclined backwardly extending handle 4 of suitable length. VOn this frame 1 is supported 'the sanding drum 5 which is positioned,v forwardly ofthe frame and is driven by any suitable means, such as an electric motor 6 mounted on and at 'the' upper side of lthe frame land adjustablev forwardly and back-l wardly thereon.

Heretofore in Sanders of the' class shown, the sanding drum was supported on arms which were fpivotally mounted on bolts 7 between the axis ofrevolution of the motor and `thus causing the furrows, grooves, or

waves-in the Hoor. In my construction, I have changed the construction of the drum supporting armsv and .loweredltheir v.pivotal axes, and have supported from the bolts 7 arms 8 which are in the form of brackets depending from said bolts. Through the lower ends of the armsv or brackets 8 extend' a unitary shaft 9 which is adapted to reinforce the lower ends of the arms 8 relative to each other, vthe shaft being non-rotatably mounted at the lower ends of the arms 8 and retained against rotation by screws 10. The lower ends of the arms 8 are also prevented from being shifted readily forwardly or backwardly by straps 11 which extend with one end around the shaft 9 and with their rear ends over the axles of the supporting wheels 2, as shown in Figs. 2 and 3.

,On the shaft 9, immediately `outwardly from .the outer sides of the lower ends of the arms or brackets 8, are pivotally mounted theA drum supporting arms 12, one at each Side of the frame, saidarms being pivotally supported intermediate their ends. On these arms v12and intermediate their pivotal mounting and the forward side of such arms, is rotatablyV mounted the sanding drum 5, they same being mounted on a spindle 13 which extends through one of the drum supporting arms and is provided at its outer end with a sprocket 14. This sprocketl/l is driven by a chain 15 extending around a sprocket 16 mounted, together with another sprocket 17, on the shaft9. It will be noted that the end of the shaft 9 on which Vthe sprockets 16 and 17 are mounted is reduced in diameter with its axisv eccentric to the main axis of the shaft 9. Thus when the set screw 10 is unloosened and the shaft 9.1-0- tated slightly, the tension on the chain 15 may be readily increased to take up forwear in the chain and sprocket. On the end of the shaft 9 opposite the reduced portion maybe provided a head9l to facilitate the turning of the shaft, as shown best in Fig.y 3.

n It will be here noted that the strap 11`on the side of the machine at which'the sprockets are located may be provided at the end connected with the shaft 9with'an eccentric bushing llt-keyed to the shaft 9 vso that the axis of rotation of the shaft in saidfstrap is concentric with .the axis of rotation of the shaft in the arms or brackets 8. i

,The sprockets 16 and 17 arepreferably secured together as a unit, as shown in Fig. 3, and the sprocket 16 is driven by the sprocket 17 The sprocket 17 is driven by a chain extending around the sprocket 19 secured to the shaft of the motor 6. Thus it will be seen that the axes of rotation of the sprockets 16 and 17 are relatively lixed axes and any play or slap in the same will not be conducted in the form of chatter to the sanding drum 5. The distance between the axes of the sprockets 14 and 16, when the sanding drum is rotated, is always fixed, thus preventing such alternate tightening and lengthening fand Vconsequent slapping in the chain as was customary in former types of machines of this class, thus further reducing chatter of the sanding drum. The drum is' raised and ylowered by the portions of thearms 12 extending backwardly from the pivotal axis, namely, the ,portions designated 12a in the drawings. The rearwardly extended ends ofthese portions are flexibly connected to arms 20 in any suitable manner for raising and lowering the sanding drum from and to the floor. On the machine is provided a dust pipe 21 which terminates at its forward` end in a diverging mouth piece or dustV pan 22 whichris positioned near thefloor behind the sanding drum 5. Dueto the fixed relation ofthe dust pipe 21 and dust .pan 22 tothe frame and the more or less great distance from thedrum 5, I have provided another dust pan 23v to fill the spacel between the dust pan 22 and the drum 5. Thisdust pan 23,1is of light construction and is pivotally mounted near its rear edge at the forward portion of the dust pan 22 and is pivotally connected near itsforward edge, by a pair of links 24, at its opposite sides to the drum supporting arms 12 immediately backwardly from the portions thereof on which the drum is rotatably mounted. Thus, when the drum is raised and lowered, the dust pan 23 is raisedand lowered therewith, permitting the dust pan 23 to be placed very close to the floor and very close to the sanding drum.

With my construction it is possible to increase the 4speed of the sanding drum fifty percent more than former machines of this class. The increase in speed causes a great deal of the dust to pass around with thc drum and upwardly. I have therefore provided a light hood 25 over and around the upper land front side of the drum, with the forward portion extending downwardly as anjapron in front of the drum substantially to the floor, as designated by 25a in Fig. 2. Y This hood 25 is pivoted at its lrear end on adust directing and supporting member 26 which preferably extends from the dust panto the hood 25. This hood may bereadily raised out of the way of the drumso that the drum may be readily accessible at all times for changing the sand paper or other sanding material.

Inmy machine I have provided a special drum, the body or outer portion of which may a split cylindrical metal member 5a. Immediately over the outer surface of this cylindrical metal member 5c I have secured a pad of sponge rubber 11. To the outer side of the pad of sponge rubber 31 is secured a pad of readily yieldable sheet rubber 32. Over the outer side of the pad of readily yieldable sheet rubber is removably positioned and secured a sheet of sand paper or other sanding material Although a sponge rubber has been used heretofore in machines of this class between the rigid drum and the sand paper, the combination of readily yieldable sheet rubber and sponge rubber has not been used to my knowledge. In sanding floors, it often happens that the nails in the floor or other obstructions on the oor are forced through the sand paper into the sponge rubber tearing both the sand paper and the sponge rubber. But withv the application of a readily yieldable sheet rubber on the outside of the sponge rubber, the latter is protected from such obstructions.

In the structure shown in Figs. 8 and 9 of the drawings, in place of the sprockets 19 and 14, mounted respectively on the shaft of the motor 6 and on the spindle 13, I have provided sheaves 41 and 42 which are provided with peripheral V-shaped grooves, as shown best in Fig. 9. Around these sheaves extends a flexible belt 43 of V-shaped cross section. On the reduced eccentric portion 9ct of the shaft 9 is an idler sheave 44 also having peripheral V-shaped grooves. The belt 43 extends around the lower side of the idler sheave 44, and when the motor shaft is rotated in the direction indicated by the arrow, the pull upon the sheave 42 is the same as that exerted by the chains in the construction described above. By reason of the use of the V-shaped belt, any raising or lowering of the sander drum, which may cause loosening` or tightening of the belt, will not affect the smooth running of the operating mechanism, and the pull upon the sheave 42 will always be about the center of revolution of the sheave 44.

Though I have shown and described a particular construction, combination afnd arrangement of parts and portions, and a certain modification thereof, I do not wish to be limited to this particular construction, combination and arrangement, nor to the modication, but desire to include in the scope of my invention the construction, conibination and arrangement substantially as set forth in the appended claims.

I claim as new and desire to secure by Letters Patent is:

l. In an attachment of the class described for sanding machines, the combination with a portable frame having supporting wheels, a sanding drum, and a motor on the frame for driving said drum, of a pair of arms positioned at the opposite sides of the forward end of the frame and secured at their upper ends thereto, a pair of drum supporting arms pivotally mounted intermediate their ends at the lower ends at the outer sides of said first arms, said drum being rotatably mounted on said drum supporting arms forwardly of said frame, means at the rear ends of said drum supporting arms for supporting said drum vfrom and resiliently on the floor, means operatively connecting said motor to said drum, and straps rigidly connecting the lower endof the first arm to the pivotal axes of the supporting wheels of the frame.

2. In an attachment of the class described for sanding machines, the combination with a portable frame, a sanding drum, and a motor on the frame for driving said drum, of a pair ofarms positioned at the opposite sides of the forward end of the frame and secured at their upper ends thereto, a pair of drum supporting arms pivotally mounted intermediate their ends at the lower ends at the outer sides of said first arms, said drum being rotatably mounted on said drum supporting arms forwardly of said frame, a second pair of arms connecting the pivotal mounting of said drum supporting arms to said frame, a wheel member mounted on the pivotal mounting of said drum supporting arms, drive Imeans operatively connect- .ing said motor and said drum, said drive means passing over and in engagement with said wheel member.

3. In an attachment of the class described foi' sanding machines, the combination with a portable frame, a sanding drum, and av motor, having a pulley mounted thereon,

mounted on said frame and adapted to drive said drum, of a pair -of arms positioned at the opposite sides of the forward end of the frame and secured at their upper ends thereto, a pair of drum supporting arms pivotally mounted on said first arms, said drum being rotatably mounted on said drum supporting arms forwardly of said frame, a third pair of arms connecting the pivotal mounting of said drum support-ing arms to said frame,a pulley mounted coaxial with said drum, a second pulley mounted coaxial with the pivotal portions of said drum supporting arms, and a belt extending around all of said pulleys for driving said drum.

In testimony whereof, lI have hereunto set my hand at Los Angeles, California, this 10th day of Julv 1929. Having thus described my invention, what' HENDRICK w. LUNDQUisT.

Images