US1960399A - Apparatus for manufacture of artificial lumber - Google Patents

Description

c. J. TAYLOR 1,960,399 APPARATUS FOR MANUFACTURE OF ARTIFICIAL LUMBER May 29, 1934.

Filed Jan. 16, 1931 ff (Q T 4 7E H ij I All Awavroe [fez/5 J f/zag fig: M #77 75 Patented May 29, 1934 APPARATUS FOR MANUFACTURE OF ARTIFICIAL LUMBER Cyrus J. Taylor, Melrose, Mass., assignor to Bemis Industries, Incorporated, Boston, Mass., a corporation of Delaware Application January 16, 1931, Serial No. 509,081

8 Claims.

This invention relates to an improved arrangement for the manufacture of sheet material such as artificial lumber comprising elongate fibrous strands, such for example as excelsior,

which are compacted together with a suitable binder that holds the strands in a firmly bound reticulated engagement. This invention is particularly applicable to a machine of the type disclosed in the copending application of Horatio W. Brown and Cyrus J. Taylor, Serial No. 345,077,

filed March 7, 1929. i

In the manufacture of artificial lumber comprising, for example, excelsior strands bound with an oxychloride cement, it is highly desirable to provide a thin, uniform coating of the strands.

A thick incrustation upon the strands is undesirable, since it materially decreases the sound absorptive qualities of the lumber as well as impair- -ing its heat insulating efiiciency. Furthermore,

, 0 the employment of an unnecessarily large amount of the binder adds objectionably to the cost of the finished product.

It is a primary object of the present invention to provide apparatus of this character which will 2 be highly effective in providing a thin uniform coating of the fibrous strands. As set forth in the above-identified application, the employment of pressure rolls to squeeze the excess binder from the fibrous material and to afford a wiping or wringing efiect is advantageous in causing the thin yet uniform coating mat of reticulated fibers. The above-identified application discloses springs yieldably urging the press rolls toward each other and causing the compacting of the mat while permitting a slight variation in the center to center distance of the press rolls from each other so that the mat may be properly pressed despite slight variations in the amount of material in the mat as it passes between the rolls.

The employment of springs for this purpose, however, has been found somewhat disadvantageous, since the pressure of the rollers increases whenever a thicker mass of material passes therebetween, and the pressure of the rolls decreases when a thin portion of the mat passes therebetween. This results in some lack of uniformity in the coating of the strands and tends to permit too heavy coating when the spring pressure is lowered.

The present invention provides an arrangement whereby the rolls are urged toward each other with substantially constant pressure despite slight,

form coating of all portions of the mat I provide a new arrangement for feeding the liquid binder onto the mat before it passes between the presser rolls, this arrangement permitting depositing of the binder uniformly over the entire width of the mat.

To permit these desirable results I have provided an arrangement wherein a relatively large volume of compressible fluid, such as air, is eifective through hydraulic means in yieldably urging the rolls toward each other, the relative movement of the rolls causing no material change in the pressure of the relatively large body of air so that the mat is treated under substantially uniform conditions despite slight variations in its thickness as it passes between the press rolls. Furthermore, I have provided an arrangement of supply pipes for the binder which includes a transverse duct with openings therein for feeding the binder onto the mat and means for overcoming the effect of the velocity head of the binder so that this material may be directed ontothe mat in streams at least approximately perpendicular to the transverse duct, thus assuring uniform distribution. 1

In the drawing:

Fig. 1 is a view with parts removed and other parts broken away showing in side elevation an apparatus for use in the manufacture of artificial lumber;

Fig. 2 is an enlarged end elevation of 'a movable bearing and associated parts shown in Fig. 1;

Fig. 3 is an elevational view of the delivery tube shown in Fig. 1; and

Fig. 4 is a transverse section through the delivery tube showing the manner in which a scraper may be arranged therein.

With reference more particularly to the draw-- ing, a mat of fibers 1 which may be formed in any desired manner as for example by the invention in the aforementioned copending application is shown passing through an apparatus com-, prising a frame indicated generally at 10 and pairs of upper and lower compacting rolls 11, 12, 13, 14, 16, 17, the rolls of the latter pairsbeing spaced to compact the fibers to a greater extent than those of each preceding pair as the mat passes therebetween. A binding material, as an. oxychloride cement, may be supplied to the mat, preferably between the rolls 11 and 13 from a distributing apparatus 18. To provide for recovering any excess of the binder which may be wrung from the mat or otherwise caused to pass therethrough, an open trough or container 19 is arranged to extend beneath the lower rolls. If

ratus by some convenient means such as a pump (not shown).

The rolls 16 and 17 which compact the mat to the greatest extent are mounted for relative movement toward and from each other and are yieldably urged toward each other by an arrangement which exerts a substantially constant and unvarying pressure at all positions of these rolls. For attaining these objectives at least one of these rolls, as the upper roll 16, is journalled in movable bearings 21 disposed adjacent each end of the roll, these bearings being mounted in vertical slideways 22 in such a manner that the upper roll may move vertically to separate from or to approach the lower roll. Each bearing 21 has a lug 23 to which one end of a link member 24 is pivotally connected, the: other end of this link being pivoted to a lever 26 at the end 2'7 thereof. This lever is mounted to pivot on a bracket 28 which projects upwardly from the frame and serves as a fulcrum for the lever. The

other end 29 of thelever opposite the link connection is pivoted to the rod 31 of a piston 32 which operates in the cylinder 33.

In order to provide for exerting a substantially constant and unvarying pressure against the piston and thus for transmitting this pressure through the connections just described to the movable bearings, I provide a pressure chamber in the form of a normally closed tank 34 of sufficient capacity to contain a relatively large volume of an elastic or compressible and expansible fluid together with a sealing fluid. A connection 36 extends between the lower portion of this tank and a port in the lower end of the cylinder 33. The pressure chamber or tank may also be equipped with a pressure gauge 37. A pump 38 is arranged with its inlet side connected to the reservoir 39 and its discharge connected to the pipe 40. A connection 41 leads from any portion of the system containing non-compressible sealing fluid under pressure, as from the pipe 36, to the reservoir 39. A valve 42 is interposed in this connection for adjusting and controlling the pressure of the non-compressible fluid. The upper end of the cylinder may also be vented to the atmosphere by a normally open port or vent 43 which permits ingress and egress of air as the piston reciprocates. While similar apparatus may be provided for movably supporting the lower roll 1'1 and for maintaining this roll under a substantially constant and unvarying pressure, this is usually unnecessary and this roll is therefore shown as mounted in fixed bearings 44.

To assure an even and substantially uniform distribution of cementitious material or binder to all portions of the traveling mat, the distributing apparatus 18 is formed of a sectional header 45 which is connected midway of its ends to supply pipe 45'. The opposite ends of this header are connected by pipes 46 and 47 with the oppo- 'site ends of a delivery tube 48, the latter being disposed horizontally and arranged to extend transversely above the path of travel of the mat 1. The. lower or under side of the delivery tube 48 has formed therein longitudinally disposed and substantially aligned slots 49 and 51 which extend from positions adjacent the ends of this tube substantially to the midpoint thereof. Preferably the material of the tube is arranged to form a bridge piece 52 which extends between the adjacent ends of these slots for strengthening the intermediate portion of the tube so as to prevent spreading thereof.

The velocity ofthe binder as it enters tube 48 has a tendency to cause this material to issue from the slots 49, 51 in streams directed toward the center of the mat so that the outer edge portions of the latter do not receive an adequate supply of binder. To overcome this condition partial obstructions in the form of transversely disposed, substantially flat vanes 50, 50 are secured in the tube 48 preferably near each end thereof for the purpose of breaking up the velocity head and causing the binder to flow out uniformly all along'the slots. With this construction the binder issues from the tube 48- in streams or jets which are approximately perpendicular to this tube. Connections between these vanes and the tube should be as small as practical to allow the binder to pass by as much of the periphery of each vane as possible and thus to keep the vanes clean. This may be accomplished by securing the vanes to the tube by means of attaching screws 55.

In order to maintain the slots 49 and51 in a free and open condition a scraper indicated generally at 53 may be fitted in each of these slots. Each scraper may comprise a member extending through the slot with which it is associated and having its upper end 54 bent or otherwise shaped to extend laterally of the slot in a direction substantially to follow the interior contour of the tube 48. Below the slot this member may have a portion 56 extending laterally in the opposite direction to a position at one side of the tube. The free end of the section 56 of the scraper may also be arranged to extend downwardly to receive an operating handle 57 by means of which the scraping device may be moved manually from one end of the slot to the other.

In the operation of the apparatus a pressure chamber or tank 34 is charged with a relatively large volume of an elastic fluid, such as a gas, vapor or gaseous mixture capable of expansion and contraction in response to changes of external pressure. Atmospheric air meets these re-. quirements and may therefore be employed for these purposes. A sealing and non-compressible fluid such as oil is also introduced into the svs tem, preferably through the reservoir 39.tothe inlet in the pump 38 and forced into the lower end of the tank to seal the elastic fluid therein. This sealing fluid will also rise through the connection 36 into the lower end of the cylinder 33 against the piston 32. The air thus sealed in the pressure chamber 34 may be maintained at any desired pressure by pumping the requisite amount of oil through the connections 40 and 36 to the lower end of the tank, thus changing the volume and the pressure of the enclosed gas. It will be apparent that the pressure at which this relatively large volume of air is maintained will be transmitted from the piston 32 through the lever 26 to the movable bearing 21 and will therefore be effective for urging the upper roll 16, mounted in these bearings, toward the lower roll 1'7, thereby tending to effect relative movement of these rolls. As the mat 1 varies in thickness and thus causes different pressures to be exerted against the rolls l6 andl'l, these pressures will likewise be transmitted through the connections just described to the elastic fluid in the chamber 34. The volume of this fluid however, is sufficiently large to be capable of expansion and contraction in response to such relative movement-of the compacting rolls without undergoing appreciable changes in pressure and for this reason the elastic fluid serves to maintain the movable bearings 21 under a substantially constant and unvarying pressure during all positions of these hearings. It will also be seen that the elastic fluid is effectively sealed in the chamber 34 by the relatively non-compressible sealing fluid here represented as oil and that this sealing fluid serves as a medium for transmitting pressure between the elastic-fluid and the piston 32. This pressure may be lowered by opening the valve 42 or increased by operating the pump 38 as desired. 1

While it is thus assured that the traveling mat will besubjected to a substantially constant and unvarying pressure during its passage through the compacting rolls, it will be observed that the distributing apparatus 18 also provides for a substantially even distribution of binder throughout the mat. The velocity of the binder as it enters the delivery tube 48 is retarded by the partial obstructions 50, 50' which cause the binder to flow out of the slots 49, 51 substantially uniformly all along the latter, thereby providing proper distribution. The arrangement whereby the binder is caused to flow from. the ends of the tube 48 toward the center thereof also tends to produce a more even distribution. In this way it is assured that an adequate amount of this binding material will be distributed over the marginal or edge portions of the traveling mat and as the supply of the binder moves along the delivery tube toward the center thereof, it is likewise a'ssured that the distribution will be equal and uniform over the central or intermediate portions of the mat.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all'modiflcations and equivalents which fall within the scope of the appended claims.

I claim:

l. The combination of rolls space-d for coacting on material passing therebetween, means for supporting the rolls for relative bodily movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure, and means for applying the pressure of this fluid for effecting relative movement of the rolls toward each other, the volume of fluid so employed being sufliciently large .to be capable of expansion and contraction in response to relative movement of the rolls without appreciable change .each other.

2. The combination of rolls spaced for coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure including means providing a liquid seal for the elastic fluid, and means for applying pressure of the elastic fluid through the liquid seal for efl'ecting relative movement of the rolls toward each other, the volume of elastic fluid being sufficiently large to be capable of expansion and contraction responsive to relative movement of the rolls without appreciable change in pressure, whereby the rolls may be caused .to coact on the material passing therebetween with a substantially constant and unvarying pressure irrespective of variations in the thickness of such material.

3. The combination of rolls spaced for coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure," including means providing a liquid seal for the elastic fluid, and mechanical means for transmitting pressure from the sealing liquid for effecting relative movement of the rolls toward each other, the volume of elastic fluid so employed being sufficiently large to be capableof expansion and contraction in response to relative movement of the rolls without appreciable change in pressure, whereby the rolls may be caused to coact on material passing therebetween with a substantially constant and unvarying pressure.

4. The combination of rolls spaced for coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure including means providing a liquid seal for the elastic fluid, a cylinder having ports at the ends thereof, a piston operable in the cylinder between the ports, means for conducting the sealing liquid to one of the ports, and means for transmitting movement from the piston for eifecting relative movement of the rolls.

' 5. The combination of rolls spacedfor coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure including means providing a liquid seal for the elastic fluid, means for changing the pressure of the elastic fluid by changing the volume of the sealing liquid, and means for applying the pressure of the elastic fluid for effecting relative movement of the rolls toward each other, the volume of elastic fluid being sufliciently large to be capable of expansion and contraction responsive to relative movement of the rolls without appreciable change in pressure, whereby the rolls may be caused to coact on the material passing therebetween with a substantially constant and unvarying pressure irrespective of variations in the thickness of such material. a

6. The combination of rolls spaced for coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure including means providing a liquid seal for the elastic fluid, a cylinder, a balance piston operable in the cylinder, means for conducting the sealing liquid into one end of the cylinder against the piston, and means for transmitting pressure between the piston and the rolls for effecting relative movement of the latter.

7. The combination of rolls spaced for coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to accommodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure, including means providing a liquid seal for the elastic fluid, a cylinder, apiston operable in the cylinder, means for conducting sealing liquid from the liquid seal into one end of the cylinder against the piston, means for transmitting pressure between the piston and the rolls for efiecting relative movement thereof, a pump, and a connection from the discharge side of the pump to the main body of sealing liquid.

8. The combination of rolls spacedfor coacting on material passing therebetween, means for supporting the rolls for relative movement toward and from each other to acconmiodate material of variable thickness, means for maintaining a relatively large volume of an elastic fluid under pressure, including means providing a liquid seal for

Images