US1736546A - Floor sander - Google Patents

Description

Nov. 1 9, 1929;

R. A. PONSELLE 1,736,546

FLOOR SANDER Filed June 11, 1924 3 SheetsSheet 1 lNVEN R FM d. Jaw z/z g ATTORNEYS Nov. 19, 1929. PQNSELLE 1,736,546

FLOOR SANDER Filed June 11, 1924 5 Sheets-Sheet 2 ATTORNEY 5 Nov. 19, 1929. R. A, PONSELLE FLOOR SANDER Filed June 1 1924 3 Sheets-Sheet BY JM2M 'Z/lma s AATTORNEYJ Patented Nov. 19, 1929 UNITED STATES Parana-caries ROBERT A. PONSELLE, OF NEW YORK, N. Y.

FLOOR SANDER:

Application filed .Tune 11,

supported on wheels and is provided with a handle, by means of which the machine may be readil moved about. The motor drives the abrad ing implement, which may conveniently take the form of a drum covered by sand paper, and in one type of machine this drum is mounted on a shaft rigidly supported in the base. The base is supported on wheels which rest on the floor and these wheels are placed a considerable distance apart so that the machine cannot tilt sideways, although it may be rocked about a transverse axis to vary the pressure with which the drum bears against the floor.

A machine of this type is not satisfactory because owing to the rigid mounting of the drum the latter always rotates about a substantially horizontal axis and consequently when used on a floor which has surface irregularities the depressions in the floor cannot be reached by the abrading surface. The result is that with this type of machine it is not possible to reach all portions of a floor which is at all irregular in surface, and parts of the floor must later be treated'by hand. This type of machine, however, having the drum rigidly mounted, has certain advantages in mechanical construction over other types of such machines which will presently be re ferred to.

In an attempt to design a machine which will overcome the disadvantages of the machine having its drum rigidly mounted, machines have been built in which the drum shaft is mounted in the ends of arms which are swivelled to the base. A machine of this type is quite satisfactory in the respect that it permits all portions of the floor to be attacked by the drum because the swivelled mounting of the arms permits the drum axis to lie at an angle to the horizontal when the 1924. Serial N0. 719,257.

contour of the floor so requires. This type of machine, however, is more complicated in construction than that previously described, since it is necessary to provide some means by which the drum may be supported clear of the floor when the machine is to be moved about with the drum out of action. Also, by reason of the fact that the arms may swing different distances to permit the drum axis to tilt, it is necessary to provide a pecul'iartype of bal.

bearing for the drum shaft in the ends of the arms, and a ball bearing which serves the purpose is quite expensive. Furthermore, the drum shaft is driven by a chain from the motor and this chain must be quite slack in order to permit the arms to swing freely. The result is that the slack chain is noisy and such a drive is mechanically incorrect.

A third type of machine now in use has its drum shaft mounted in slots in the base, the ends of the shaft lying in bearing blocks which are acted on by springs so that the shaft is pressed downwardly so as to cause the drum to lie in contact with the floor. With this arrangement the drum shaft may assume a position at an angle to the horizontal whenever the surface contour of the floor requires, but again this machine has the several disadvantages pointed out in connection with the machine in which the drum shaft is mounted in the ends of swinging arms. The last two types of machine described, therefore, while being more satisfactory than the first, in that all portions of the floor may be acted on, are objectionable because of their expensive and complicated mechanical construction.

The present invention is directed to the provision of a machine which affords the several advantages of the machines above described, but which is without their disadvantages. This machine is so arranged and constructed that although the drum has a fixedv mounting so that the mechanical construction is quite simple, yet it may still reach all portions of the floor by reason of the rocking of the base of-the machine on its support. This support is arranged so that the machine may rock about ahorizontal axis which may be varied so as to shift as much or as little of the weight of the machine on the drum as may be desired, thus altering the pressure at which the abrading action takes place. The bearing of the support upon the floor is approximately in the longitudinal axis of the machine so that when the machine moves over a smooth surface the drum assumes a horizontal position. As the machine is moved over the ordinary floor, however, it encounters irregularities which exert unequal pressure on the ends of the drum, but since the support lies susbtantially on the longitudinal axis of the machine, this pressure on one end or the other of the drum causes the entire machine to tilt about its longitudinal axis, thus permitting the drum to follow the uneven floor surface closely. At the same time, since the drum is rigidly mounted in the base it is not necessary to provide expensive ball bearings, nor is it necessary to provide some means by which the drum may be secured in position free of the floor, when the machine is moved thereover and the abrading action is not to take place. Also, it is possible, with this type of machine, to use a drive chain for the drum in which there is no considerable slack. Thus the drive is not noisy and the moving parts are not so quickly worn.

In one embodiment of the invention, the support consists of a shaft on which are mounted two wheels, ordinarily placed close to 'ether and substantially in the longitudinal gravitational axis of the machine. The drum, covered with a facing of sand paper is supported in fixed hearings in the frame of the machine and is driven from the motor. \Vith this arrangement the machine may be considered to have a three-point contact with the floor, the two wheels placed close together constituting; one point, while the ends of the drum provide the other two points. With this three-point contact support for the machine, it will be seen that it accommodates itself to floor irregularities without the necessity of the operator attempting to vary the position of the machine according to the floor contour. Ordinarily the drum is covered with the abrasive paper throughout its length, but under certain conditions, as, for instance, when an unusually irregular floor is to be treated, a strip of paper is used which covers only a portion of the drum at one end. When a drum so covered is used the supporting wheels are spaced apart a considerable distance, one of these wheels beinp; moved toward th side of the base at which the covered end of the drum lies. lVith this arrangement the machine again has a three-point contact,

one of these points being that end of the drum covered with the paper, and the other two points being the wheels.

This type of machine, therefore, is as simple in mechanical construction the first type of machine, andat the'same time affords the advantage of reaching all parts of the floor, which has been gamed heretofore only by the use of machines of a much more complicated and expensive construction. In addition to these desirable features, the machine is provided with a suction blower for removing the sawdust, etc., and with the drum rigidly held in the base, the hood connected with the blower may be placed in close proximity to the drum so that the blower operates with great efliciency.

In the accompanying drawings I have illustrated that type of machine which is now preferred, and in these drawings,

1 is a side view of the complete machine,

Fig. 2 is a top plan view with certain parts broken away,

Fig. 3 a vertical sectional view on the line 33 of Fig. 1,

t is a horizontal View, partly in section, on the line 4 4: of Fig. 1,

1: 1;. 5 is a bottom plan view of the device,

Fin; 6 is a diagrammatic view illustrating the present machine operating on a floor surface of irregular contour,

Fig; 6 is a view similar to Fig. 6, showing a machine of the prior art in similar use,

7 is a cross sectional view through the drum illustrating the manner in which the sand paper held on the surface thereof, and

Fig. 8 is a development of a piece of sand paper used on. the drum.

Pteferrin now to these drawings, the machine will be seen to consist of a base or frame 9 which may be made of a pair of similar castings bolted together along their edges. These castings are soformed as to give the base a flat top from which depend side members and a rear end member. Mounted on the fiat top of the base is an electric motor 10 of an desired construction, the leads 11 for which upwardly to a switch box 12 mounted conveniently on a handle 13. This handle is carried on a pair of arms 14: which are swivelled on a shaft 15.

The shaft 15, (see Fig. 1) lies in one or the other of a series of notches 16 formed in the lower edges of the side members of the base near the transverse axis of the machine. Pivotally mounted on the base near one end of each of these groups of notches is a latch arm 17 swinging on a screw 18. At the other end, the latch arm has a slot 19 in which lies a screw 20 secured to the base, and the latch arm may be released from position by unscrewing the screw 20 then swung downwardly so that the shaft 15 may be placed in any desired notch. The notch in which the shaft lies will determine the extent to which the weight of, the machine will. bear on the sanding drum as will later be described.

The sanding drum is mounted on a. shaft 21, supported in bearings at the front end of the base and, at one end, is provided with a ball bearing 22 of the usual construction which is disposed within a housing 23 mounted in an end plate 23"' forming part of the base. The end plate 24 of the drum is mounted loosely on the shaft21 and partially encloses the inner end of the housing 23. At its end the shaft carries check nuts 25 to hold it in position, and the escape of lubricant from thebearings is prevented by a felt washer 26 interposed between the bearing and the inner end of the housing, auc. the cover plate 27 is secured in place to the housing 23 by screws 28. At its other end, the shaft 21 passes through a similar housing 29, mounted in the plate 29 forming part of the base, and inthis housing is a ball bearing 30, on either side of which are placed felt washers 31, which lie between the bearing and the inner and outer end plates 32 and respectively, of the housing. The shaft extends through the outer end plate, through a spacing sleeve 34, and at its outer end carries a grooved pulley 35 and a sprocket 36; The latter lies within a casing 37 which encloses the drive chain 38 and a second sprocket on the end of the shaft 39 of the motor.

The inner end of housing 29 is partially enclosed by a plate 40 having a counterweight extension 40 which, with the plate 24, sup ports the drum 41, which is held in place between the plates by screws 42. The end plate 40 is secured to the shaft by a dowel pin 45. Mounted in the end plates to underlie a slot 44, extending from end to end of the drum at an angle to the longitudinal axis, (Fig. 5), is a papertightening shaft 45, one end of which carries a ratchet wheel 46 against which bears a pawl 47 mounted on the end plate 40. The other end of the shaft is squared and extends through the other drum end-plate which is recessed, as at 48, so that a wrench may be applied to the end of the shaft for turning it. The shaft is slotted longitudinally, and has an extending flange 45 dis-V posed along this slot. The cylinder 41 also has an inwardly extending flange 41 adapted to cooperate with the flange on the shaft 45. To the surface of the cylinder is applied a layer of felt 49 and the sand paper used for treating the floor is applied to the surface of the drum over this layer of felt and its ends are inserted in the slots through the drum and the shaft. In this operation the shaft 45 is turned to the position illustrated in Fig. 7, where it will be seen that the flanges 41' and 45 serve to provide a guideway that the ends of the paper may readily be inserted through the shaft slot. iVheu the shaft is turned the ends of the paper are gripped and the shaft may be turned so as to provide any desired tension on the paper.

It will be noted that the pulley 35 and sprocket 36 are held in position against he separator 34 by a nut 50, and are keyed to the shaft by keys such as 51. The shaft has a portion of reduced diameter which extends from the nut 50 to the inner end of the separator which lies against the shoulder so formed. The ball bearing 30 also bears against a shoulder formed in a similar manner and the parts are thus held in fixed relation by tightening the nut 50.

Mounted within the rear end of the base is a blower shown in dotted lines at 52 in Fig. 1. This blower may be of any convenient and compact type and is here illustratel consisting of a casing within which is a plurality of driven vanes. The blower shaft 53 extends outwardly through the base and is driven by means of a round belt 54 which runs over the grooved pulley 35. The blower is thus driven from the drum shaft which is in fixed position all times. The blower housing is connected by a pipe 55 with a hood 56 which encloses a portion of the drum.

At the front end the base above the drum is pivotally mounted a shutter 57 which includes a plate which may be moved to different p0,". tions of. adjustment relative to the drum. This shutter may be adjusted so that the plate lies close to the drum surface and this prevents particles of wood being carried around by the drum and thrown out of the machine, and also concentrates the flow of air at the bottom of the hood where the saw dust being created. Inasmuch as the drum is mounted in fixed bearings the hood 56 may be formed so as to lie close to its surface and also to extend around it to a point near the floor. The suction effect of the blower thus becomes hi hly effective to remove loose sand and particles of material scraped frointhe floor by the sand paper on the drum. The air drawn in through the hood passes through the blower housing and the pipe 58 to the bag 59, where the refuse material is collected.

As has previously been described, the base is supported on a shaft 15 which lies in notches formed in the lower edge thereof. This shaft carries two wheels which bear against the floor as shown in Figs. 4 and 5. These wheels 60 are of similar construction and are provided with a central boss 61 having a: bore of large diameter. Between the shaft 15 and the inner surface of this bore is mounted a plurality of roller bearings 62 which are held in place by washers 63 lying against the ends of the boss and held in place in that position by means of cotter pins 64 which pass through bores 65 formed in the shaft.

The wheel 60 shown at the lower end of the shaft in Fig. 4 is fixed in position while the other wheel is capable of adjustment to different positions along the shaft 15. When a completely covered drum is being used, the wheels will be placed relatively close together and on either side of the longitudinal gravitational axis of the machine, which will lie nearer one side than the other due to the weight of the driving connections. With this auangement, the machine may be considered to be supported at what amounts to a single point in the axis above referred to so that if one end of the drum strikes a high point in the floor, the force exerted is sufficient to tilt the machine so that one wheel may be lifted from the floor, thus permitting the drum to bear against the floor substantially throughout its length. Obvious y, by varying the number or spacing of bores in shaft 15, or by using other well known adjustable means such as set screws in the hubs of wheels 60, these wheels maybe spaced anywhere desired along shaft 15 in order to suit various floor conditions.

Referring to Figs. 6 and 6*, these figures show somewhat exaggerated views of two machines in use, Fig. 6 illustrating a machine constructed in accordance with the present invention passing over an irregular floor, while in Fig. 6* there is shown a machine of the prior art having its drum rigidly mounted in the base, passing over the same irregular floor.

It will be seen that with the old type of machine illustrated in Fig. 6 the spacing of the wheels 66 prevents the drum 67 from reaching the floor except at one end, while with the present machine, as shown in Fig. 6, the same irregularities would cause the whole machine to rock laterally, lifting one wheel from the floor, but permitting the drum to contact with the floor through substantially its entire length. lVith the old type of machine one end of the drum is forced against the floor with the entire weight of the machine, which is, of course, undesirable, but with the present machine, as shown in Fig. 6 substantially the entire length of the drum is in contact with the floor and the pressure is evenly distributed. The present machine, consequently affords all the mechanical advantages of the old type of machine and in addition is so constructed that all portions of an irregular floor may be acted on.

Where floors of unusually irregular contour are encountered, it may be desirable to make use of a drum of which only a portion of the surface is covered as is shown at 68 in Fig. 5. With this strip of paper around one end of the drum the movable wheel 60 will be moved along the shaft 15 so as to lie substantially in a line with the strip of paper. With this arrangement it is always certain that the covered portion of the drum will lie in contact with the floor for any irregularities in the floor which would cause the center portion of the drum to be held clear of the floor boards or to be forced against them with unusual pres sure, will now be without effect. The center portion of the drum is uncovered and therefore of less diameter than the part on which the paper is held. The covered portion of the drum however, being in aline with the wheel 60, will always lie against the floor so long as that wheel bears against it, especially since the drum has a yielding surface due to the layer of felt under the paper.

then the wheels are close together on the shaft the machine has a substantially threepoint support. These points are the ends of the drum and the pair of wheels, which being arranged close together, act as a unit. If one end of the drum is raised by hi h spot in the floor, this pressure'will cause t ie machine to rock on the wheels so that the drum may conform to the floor surface. This three-point contact therefore acts naturally to give the drum its greatest efficiency. If the high point in the floor bears against the middle part of the drum, then the machine will tilt either to one side or the other so that one end or the other of the drum may be effective. With the other arrangement in which but one end of the drum is covered and the wheels are spaced a considerable distance apart, the machine again has a threepoint support. In this case, the covered portion of the drum acts as one point while each of the two wheels act separately as the other points. The machine is now unaffected by floor irregularities and the covered portion of the drum will always be efiective because it lies substantially in a line with one of the wheels.

I have found it desirable to secure the paper in position on the drum by means of the shaft 4:5 as described, but if the slot it extends parallel with the axis of the drum, the slight irregularity in the drum surface due to the slotcoming into contact with the floor would cause the drum to jump up and down off the floor. In order to counteract this tendency I forni the slot at an angle to the axis, but if the paper he now pulled tight by the shaft it will be found that since the sides of the slot lie along a curve due to their extending slightly around the drum, the paper will be drawn tent at the middle but the edges will be somewhat loose. In order to overcome this I cut the paper to the shape shown in Fig. 8. At the ends, I cut out one or more darts 68, and these portions of the paper pass through the slot in the shaft 4L5. As the ends are drawn taut, the paper bulges out slightly due to the drawing in of the sep arated ends as shown in the dotted lines in Fig. 8, and this bulging occurs at the central point so that the paper will fit the edge of the drum slot. With paper formed in this shape the shaft 45 will tighten the paper evenly along the edge of the slot and the drum is thus smoothly covered with paper drawn to a uniform tautness.

In order that the machine may be handled conveniently the handle arms 14: are swivelled to the base and one of these arms has a horizontal portion which lies between spaced lugs 69 on a plate 7 0 adj ustably secured to the frame by a bolt and slot mounting. The plate 70 is placed in such a position of adjustment that the cross bar of the handle will lie at a convenient height without the handle arm coming into contact with either lug. Thus, as the machine is pushed along, the force exerted by the workman has no tendency to rock the machine about its transverse axis because the handle arm lies free of the lugs on the plate. Also, by reason of this provision of the horizontal portion of the handle arm, the cross bar of the handle lies at the same height for each adjustment of the plate, regardless of the notch in the frame in which the shaft 15 is placed. When it is desired to raise the drum from the floor the cross bar of the handle is pushed down until the handle arm comes in contact with the lower lug 69 and the machine may then be rocked about its transverse axis so as to raise the drum from the floor. Under ordi nary conditions the handle may move up and down slightly without causing this rocking of the machine, since the space between the lugs is greater than the width of the handle arm, and with this arrangement the workman cannot unintentionally rock the drum free from the floor, in moving the machine about.

The machine of the present invention will be seen to overcome the various disadvantages inherent in those machines in which the frame is given a substantially fixed support with relation to thefloor with the drum free to move up and down either in swinging arms or in slots in the base, since it is not necessary to provide any additional means for holding the drum clear of the floor when the machine is out of action, nor is it necessary to provide the expensive ball bearings which permit the tilting of the drum shaft at an angle to the horizontal. Also it is possible to drive the drum by a taut chain, and thus the drum drive is quiet and does not wear quickly. At the same time the machine of the present invention is so arranged that the drum may accommodate itself to floor irregularities. The present invention also has the mechanical advantages of that type of machine previously described, in which the drum has a rigid mounting but which is carried on a wheeled support such that the machine cannot tilt, but the present machine avoids the disadvantages of that type of machine since by reason of the rocking of the machine on its support, the drum can reach all portions of the floor, which is not the case with the older type of machine. lVith the drum rigidly supported in the base the hood for the blower may be placed in close proximity to its surface, thus increasing the effectiveness of the blower, with the result that practically all the sawdust, sand, and the like, is removed as the machine is moved along.

I claim:

1. A machine for treating floors which comprises the combination of a frame,amotor mounted thereon, a drum mounted in fixed hearings in the frame, and driven by the motor, this drum bearing against the floor when the machine is in use, and a support for the frame movable over the floor this support contacting with the fioor and normally lying substantially in the longitudinal gravitational axis of the machine, the support permitting rocking of the mac line on said axis and being adjustable to permit the machine to rock about a second axis parallel to but spaced from the first. i

2. A machine for treating floors, which comprises the combination of a frame, a motor mounted thereon, a drum mounted in fixed hearings in theirame and driven by the motor, this drum bearing against the floor when the machine is in use, and a support for the frame movable over the floor and arranged to permit the frame to rock about a transverse axis according to inequalities in the floor surface and also to rock about any predetermined axis parallel to the longitudinal axis according to differences in the pressure with which the ends of the drum bear against the floor, this support being adjustable toward and away from the drumto vary the pressure with which the latter bears against the floor surface.

8. A machine for treating floors which comprises the combination of a frame, a motor mounted. thereon, a drum mounted in fixed bearingsin the frame, and driven by the motor, this drum bearing against the floor when the machine is in use, and a pair of wheels for supporting the frame relative to the floor, these wheels being mounted in the frame with their axes parallel to the longitudinal axis of the drum, and being capable of adjustment to different positions toward and away from the drum, and also toward and away from each other to shift the axis of floor contact of the machine into any longitudinal plane.

4. A machine for treating floors which comprises the combination ofa frame, a motor mounted thereon, a drum mounted in fixed bearings in the frame, and driven by the motor, this drum bearing against the floor when the machine is in use, and a pair of wheels for supporting the frame relative to the floor, these wheels being mounted in the frame with their axes parallel to vthe longitudinalaxis of the drum, and being adjustable to different positions toward and away from each other to shift the longitudinal axis of floor contact of the machine.

5. A machine for treating floors which comprises the combination of a frame, a motor mounted thereon, a drum mounted in fixed bearings in the frame, and driven by the motor, this drum bearing against the floor when the machine is in use, a support for the frame movable over the fioor, this support contacting with the floor and normally lying substantially in the longitudinal, gravitational axisof the machine and permitting rocking of the machine on said axis, the support being adjustable to permit the machine to rock about a second axis parallel to but spaced from the first, and means for attaching the support to the machine permitting adjustment of the support toward and away from the drum without disturbing the rela tion of the support to the longitudinal axis of the machine.

6. A machine for treating floors which comprises the combination of a frame,a motor mounted thereon, a drum rotatably mounted in the frame in fixed bearings, a support for the frame mpvable over the floor, a blower 0n the frame, an intake conduit for the blower terminating in a hood partially enclosing the drum, driving connections by which the motor drives the drum and the.

blower, and a plate mounted on the frame at the upper edge of the hood and adjustable toward and away from the drum to regulate the flow of air over the upper surface of the drum.

7. A machine for treating floors which comprises the combination of a frame, a mo tor mounted thereon, a drum mounted in fixed bearings in the frame, and driven by the motor, this drum bearing against the floor when the machine is in use, a shaft mounted in the frame parallel to the axis of the drum, and capable of being placed in different positions of adjustment relative to the drum, and a pair of wheels mounted on the shaft and capable of relative adjustment thereon, said wheels cooperating with the drum to support the machine.

8. In a machine of the class described, the combination of a frame, a drum rotatably mounted therein, a shaft mounted in the frame parallel to the axis of the drum and adjustable toward and away from the drum a wheel on the shaft rotatably mounted in in a fixed position and another wheel rotatably mounted on the shaft and adjustable therealong, said wheels cooperating with the drum to support the machine.

9. A machine for treating floors which comprises the combination of a frame, a sand ing drum rotatably mounted in the frame, a motor mounted on the frame for driving the drum, a pair of arms swivelled on the frame and terminating in a handle, and a plate adjustably mounted on the frame hav ing lugs between which one of the arms extends.

10. A machine for treating floors which comprises the combination of a frame, a sanding drum rotatably mounted on the frame, a motor on the frame for driving the drum. a pair of arms swivelled on the frame and nvsasee andle, one of these arms ing in a substantially d a plate adjustably d having lugs beal portion of the ERT A. PONSELLE.

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