US2231921A - Wood surfacing machine - Google Patents

Description

Feb-1s, 1941.

J. H. KITLAR ETAL WOOD SURFACING MACHINE Filed Oct. 18 1958 Patented Feb. 18, 1941 PATENT OFFICE 2,231,921 Woon sUnFAcING MACHINE Joseph H. Kitlarland Joh-n Johnson, Tacoma,

, Wash.

`Application october 1s, 193s, seriailvNo. 235,620

6 Claims.

This invention relates to wood surfacing machinos and surfacing processes, and has reference more particularly to improvements in sandf ing machines; it being the principal object of this invention to provide means, operable in conjunction with the usual types of surfacing or sanding machines to produce a finer grade of' sanding and smoother surface on a board or panel for subsequentl finishing, such as staining, varnishing and polishing, and as a final result, to produce better, as well as a more beautiful finish on the panel.

Explanatory to the present invention,it Will be,

here stated that in the manufacture of certain pieces of furniture, a considerable amount or even all of the parts used have at, even surfaces to be finished or prepared by application of stain and varnish, and subjected tovarious polishing operations; these parts being initially prepared by passage through various planing and sanding machines. The boards -or panels employed are of various kinds and qualities of wood, varying considerably in the character of fiber or grain of the wood, as well as in hardness. The planing and sanding operations are designed to form the pieces or panels with surfaces which are as level and smooth as can be obtained. However, in use of planing and sanding operations. of present day machinesvknown to us, there is an objectionable feature in that the hard, long fibers of the wood resist removal from the board on an even level with softer and smaller fibers of the board, and as a result, the surface is left with a vast number of ridges and hollows, and also a vast number of extending or loose fibers. Thus, when stain, or the like, is subsequently applied, these extending or loose fibers have an increased tendency to stand up, and when the varnish is applied, they will extend even beyond the surface thereof. During the subsequent polishing operations, these fibers, of course, are broken off, but in their breaking off, they actually present minute openings to the wood beneath thevarnish,

and upon those surfaces which are subjected to considerable wear, or Where the varnish, becomes worn, the Wood will be exposed, or at least access will be provided thereto through the enlargement of ,these minute openings. Due to these openings and to varying temperatures and humidities, the wood then, in, damp Weather, has a tendency to absorb moisture from the air, and in warm Weather, to dry out. Moisture absorbed by the4 wood tends to separate the varnish from the wood, and causes the iinishto blister, crack,

(Cl. 51-u5) and check, and to deteriorate in general appearance and usefulness.

The final result is a product of short life in regard to the finish thereof and the conclusion is that it is of cheap, 10W grade material.

Many attempts have been made to reduce or minimize the fuzziness of the panel surfaces caused by the extending of harder fibers of the wood, such as by the manual sponging 0f boards with water between the customary operations of coarse and fine sanding. This sponging of the board surface with water causes the loose fibers to swell and stand more out from the board,

remedying `the situation to a limited degree, but there still is a tendency for the subsequent sanding operations to knock down the fibers instead of entirely removing them. This hand sponging has its disadvantages in that in rubbing over the board surfaces with the sponge, the extending fibers are matted down considerably and only the larger ones are caused to stand, by reason -of the moisture absorbed.

The present invention deals with novel means and Vmethods for conditioning and surfacing lumber or wood panels, that allows for the removal of such extending fibers or fuzziness, to the maximum degree.

In view of the above, it has been the object of this invention to provide means whereby the fibers of wood that extend from the board surface are caused to stand up, and are so held up that they may be completely removed in a subsequent sanding operation.

It is a` further object of this invention to provide for the automatic application of a liquid s0- lution to the board surface as it travels out of one of the sanding machines, thus eliminating the need and expense of the slow and ineicient manual sponging, and at the same time providing for a completely efficient fiber raising sizing at v no added expense.

It is a still further object of this invention to provide a clean and sanitary means of mechanically applying this liquid solution to the Wood panels, thus eliminating the possibilities of the smudging of the panels by the wet hands of the operator.

Still further objects of the invention reside in the details of construction, in the combination of parts, and in the mode of operation of the device, as will be hereinafter fully described.

In accomplishing these and other objects of theinvention, We have provided the improved details of construction, the preferred forms of which litiv are illustrated in the accompanying drawing, wherein- Fig. 1 is a longitudinal, sectional view of a sanding machine embodying the present invention.

Fig. 2 is a detail of the mounting of the fabn'- cated sponging rollers upon the sanding machine.

Fig. 3 is an enlarged, cross sectional view of the sponging roller, illustrating its action upon the wood fibers. f

Fig. 4 is a partial sectional detail of the solution distributing pipe. f

Briefly described, our invention resides in the means for causing the lifting up of the loose wood bers from the surface of the`A lumber or panel operated on, comprising fabricated, absorbent rollers that are supported for rolling contact with the flat surfaces of the boards or panels as they emerge from the sanding machine, and means for applying a suitable sizing solution, which may be similar to or in fact may be a very thin or diluted solution of glue, tothe rollers for transfer to the surface of the board.

Referring more in detail to the drawing- In Fig. 1, we have illustrated, somewhat diagrammatically, a sanding machine of a type now in common usage. This machine is designated in its entirety by reference numeral I0, and` it comprises a frame I2 within which an endless belt conveyor I3 is moved in the direction of the arrows adjacent thereto, by the drums or wheel I 4--I4' about which the belt operates. These drums are mounted yon cross shafts I5-I5 revoluble in the frame and which may be driven by any suitable means.

The board or panels to be surfaced such as designated at I8, are inserted in the machine upon a bedplate I'I and the pressure block I8 pressed downwardly thereon to hold the board for even motion through the machine.

In the type of machine illustrated, a plurality of sander heads are employed, and these are eachA designated by reference numeral 20. Each head comprises a drum 2| that is' supported and rotated at high speed by a supporting cross shaft 22. On ythe drum is a wrapping, or surface of sand paper, or the like, 23. Enclosing each sander head is a hood 25, each of which is connected to the adjacent one for rigidity, and each is connected at its upper end to a suction pipe 26' for the removal of the sander dust.

As the board panel I8r emerges from the sanding machine, it is advanced across another bed. plate 2l, above which is suspended the present,

' solution applying or sponging roller, designated at 30. l

In the present instance, the roller 30 comprises a metal drum 3l that is closed by end plates 3Ia, and is supported by a coaxial shaft 32. This drum is wrapped with a plurality of layers of absorbent material, preferably a heavyv felt, such as wool felt; ythis being designated at 33. At its opposite ends, the shaft 32 is secured to the swinging ends of paired arms or brackets 35 by bearing blocks 36. Each bracket or arm 35 is hinged, as at 37, to a part fixed to the sander frame, thus to permit the roller to raise and lower. Adjusting studs 38 are threaded through the brackets 35 to engage with brackets 39 which are xed to the frame and provide adjustment in accordance with various thicknesses of boards.

A pipe longitudinally overlieshthe roller 30 and is supported at its ends by clampslll that: are

fixed upon the hinged brackets 35. 'I'his pipe is capped at both ends, and has a valved connection, as at 43, centrally thereof, with a source of supply of liquid solution, not shown, through a flexible hose 44. The pipe 40 is provided with a plurality of jets or openings 42 along its lower side as noted in Fig. 4, disposed in such a manner as to spray a solution on the roller at a rate sucient to keep it saturated.

It'.A will be noticed that the bed plate 21 is provided with a series of grooves or channels 45 leading from a cross groove or channel 46 adjacent the inner edge thereof, and inclined slightly tothe outer edge thereof, and that there are also provided holes 41 through the bed plate from the bottom of the grooves. 'I'his allows the solution to drain freely to the pan 48 that underlies the bed, plate 21', and thereby prevents it from entering the sanding machine.

The pan 48 drains into a trough 50 which is permanentlyl xed to the frame of the sander by a bracket 68. Sufcientsolution is maintained in the trough 50 by overflow or seepage from the upper roller;

A second roller, identical in construction to roller 38', is disposed beneath the path of travel of. the panel, and is supported to rotate in the trough 50. This roller is adapted to be in rolling con-tact with. the lower surface of the panel as it emerges from. the Sanden. and is mounted on a frame designated by reference numeral 55. This frame comprises side beams 55, that are joined rigidly together at their outer end b-y beams 56a and has a, downwardly extending bracket 51 to which the shaft 32 of the roller is secured by the bearing blocks 3G. The side beams 58 are mounted by two bolts 58S, which are threaded into the bed plate 2'I. It' will be noted that there is a horizontally directed slot 58a in the end of the side beam 56, which is adapted to fit about one of theA bol-ts 58 and that there is a downwardly directed slot 53h in the lower side of the side beam 56, whichA is adapted to fit about the other bolt 58. This provides that should it be desired to process onlyY the top surface of the panel I6, the lower roller may be removed by lifting the outer end of the frame 55, which will pivot on the farther bolt 58 as the slot 58h clears the forward bolt 58, and then pulling forwardly on the frame it will slide off the farther bolt 58.

Considering the device to be so constructed, its use and mode of operation would be as follows:

With the lumber cut approximately to the size for use and after it has received the planing operation, it is then given a rough sanding operation, vas it is called, but in reality it is substantially fine sanding through the machine herein illustrated. As the boards emerge from this machine, they are. treated or processed by the rollers, then allowed to dry, and subsequently given what is termed the fine sanding operation, which is a much finer grain sanding than the first.

The action of the roller, being composed of the wool felt as described, and saturated with the solution desired', is to meisten and to lift the minute fibers of the wood, as illustrated at f in the enlarged illustration in Fig. 3. This is accomplished by the tendency of the wool fibers of the roller to be pressed into and cling to the bers of the wood. As the surface of the roller disengages the wood-panel, it moves substantially directlyv perpendicularly thereto, and in this Way,

the fibers ofthe wood arelifted, or pulled straight up from the board substantially perpendicular thereto.

With the roller being super-saturated with the liquid solution, as it rolls over the board, a cer- 5 tain amount of this solution is squeezed out of the roller and forms a small pool or run of liquid in front of it. This liquid is absorbed by the Wood to som-e extent and has a tendency -to cause the coarser fibers to swell andv to stand erect on the panel surface, thereby allowing the fibers of the wool felt roller to penetrate deeper and pick up the softer and finer wood bers.

It is anticipated also that for quicker drying of the sizing solution, and greater eiciency of the process, the lumber panels may be passed through a heated drying chamber while fibers are erect, and then given the ne sanding operation.

Should it be desired to process only the top surface, the lower roller may be quickly and easily removed, and the trough 50 suitably covered and protected. In cases where both sides of the panel are processed and finished, it is intended to run the panel through a machine, an ordinary sander, not equipped with the processing roller, then turn it over and pass it through the sander herein disclosed which is equipped with the two rollers. In this way both sides of the panel may be sanded and processed, then dried as stated for ensuing sanding operations. It is evident that should it be run through the sander and processed on its upper side, then turned over and run through again, that the rst processing would be nullified entirely by the second operation.

It is also contemplated that a plurality of such rollers for the second or final sanding may be incorporated directly in the machine or may be assembled in a unit separate or entirely independent of the sanding machine and may comprise single rollers or a plurality thereof. In Fig. 1 We 40 have designated sanding rollers for the final surfacing operation at Zlx and Zly.

Such a provision makes possible a partial completion of the process of finishing the lumber, such as performing the planing and rough sanding of the board pieces, and then the storingk of such lumber before it is finally finished or made up into finished products, as is many times the case when large orders are placed for a delivery at a future date.

A wide variety of materials may be used in the construction of the sponging roller, some having greater eiiiciency than others for certain types and qualities of wood.

It is thought quite evident from the foregoing 55 description that the superiority of this method and means of so processing lumber, over the manual swabbing or sponging will be apparent, especially in view -of the fact that such hand performed operations merely apply the solution,

and tend to brush the fibers fiat instead of uiting them up to a perpendicular position.

It is not intended that the claims be limited to the details of the devices herein illustrated, but that they be given an interpretation commensurate to the spirit and scope of the invention herein disclosed.

Having thus described our invention, what we claim as new therein and desire to secure by Letters Patent is:

1. A panel surfacing machine comprising means for advancing a Wood panel through the machine, a sanding roll for initially surfacing a face of the panel, a sponging roller supported for rolling contact with the sanded face of the said panel as it is advanced from the said sanding roll and a fine sanding roll operable for finally surfacing -the sponged face of the panel.

2. A panel surfacing machine comprising means for advancing a wood panel through the machine, a sanding roll for initially surfacing the panel, an absorbent sponging roller supported for rolling contact with the surfaced face of the panel, means for applying a moistening liquid to the sponging roll and a fine sanding roll for finally surfacing the sponged face of the panel.

3. A panel surfacing machine comprising panel sanding means, means for advancing a wood panel through the machine for the initial surfacing of a face thereof by the sanding means, a sponging roller having a covering of absorbent, resilient material for containing a sponging solution, mounted for rolling contact with the initially surfaced face of the panel as the latter is advanced, a supply pipe overlying the sponging roller and formed with perforations for supplying a `liquid sponging solution therethrough to the roller and a ine sanding roller operable for finally surfacing the sponged face of the panel.

4. A machine as recited in claim 3, wherein the sponging roller comprises a revoluble drum, equipped with a covering of absorbent felt, or the like, and is swingingly attached to the machine frame to raise and lower for passage of the panel thereunder, and wherein the solution supply pipe longitudinally overlies the roller and is supported to raise and lower therewith.

5. A machine comprising means for surfacing the opposite faces of a wood panel, rollers arranged for passing of the surfaced panel between them and for rolling contact with the surfaced faces of the panel, means for applying a sponging solution to the rollers; said rollers comprising a resilient, absorbent surface portion from which the solutionA will be squeezed by the passing of the board and ne sanding rollers operable for nally surfacing the sponged faces of the panel.

6. A panel surfacing machine comprising a rotary sanding roll, an absorbent roller, means for passing a panel through the machine for surfacing by the sanding roll and for causing its surfaced area to pass against the absorbent roller; said latter roller being of a resilient material adapted to be compressed along the line of contact incident to the passage of the board, means for supplying a liquid to the roller for sponging the panel by release incident to the compression of the roll and a ne sanding roller operable for finally surfacing the sponged faces of the panel.

J OSEPH H. KITLAR. JOHN JOHNSON.

Images