US 1201285 A
Description (OCR text may contain errors)
JAMES w. GRAY, or Tacoriawasniveroim LOCK-JOINT FLOORING.
Specification of Letters Patent.
Patented Get. if?, 1916.
Application ined August 10, i915. y serial No. 44,740.
contiguous edges of the boards are cut.
The objects of the invention are to Vprovide such a shape as will eliminate the defects in the common tongue-andgroove form at present in use; especially, preventing the vertical sliding and creaking' of one board past the adjacent board between the sup'- ports, providing a tight joint between said boards even though the boards mayshrink apart slightly, allowing for a greater depth of wear in the upper' surface of the boards without VVreducing the strength of the joint, increasing the strength of the joint, providing a form which will not be easily injured when it is being nailed in place, providing a means whereby one board on being fasteneddowii locks the joint between it and the adjacent board against vertical movenient, providing` a joint which may be put together even though the boards may be slightly swollen by dampness, and Vvproviding a shape whichitself pi'otects'its wearing edges from injury when beingA shipped. I attain these and other objects by .the devices and arrangements illustrated in the accompanying drawings, in which- Figure l is a section on an enlarged scale of a` strip of myimpi'oved flooring showing it in position in relation to lthe adjacent board on one side and showing the edges ofthe Ynent adjacent board on the other side being inserted in place;Fig. 2 is a perspective view showing parts of'two boards laid to form a floor; Fig. 3 is asection of one of my improved flooring `.boards showing the Vnail passing therethrough and into the supporting joist; Fig. 4 is an end elevation of a floor being laid illustrating how a board which has been slightly swollen is laid; and l? ig. 5 is an end elevation showing a number of boards as they are stacked and secured together for shipment. i. y y
Similar numerals of reference refer to similar parts throughout the several views.
YReferring to the construction illustrated inthe drawings The top or wearing surf face l-is madeof standard width from edge` Y y to edge and the lower or .bearing surface 2 is slightly narrower. One side of the board is provided with a lip while the other is provided witha corresponding recess. Referring first to the side having the lip, we
will follow its course from the wearing surAv face l to the bearing surface `2. This side' leaves the surface l at a right-angle, asat 3, but curves outward on a circular arc 4,
forininga vconcave surface which extends to the endvof the lip 5; then it passes vertically downward a short distance, as at 6, thus forming the end of the lip;l then it passes'v inwardon a linev 7 which is inclined about 3 degrees downward from the horizontal, said line 7 passing inward about twice the distance thatthe linee extends outward from the edge 3, thus undercutting the said edge `3 and forming the tightening under surface of the lip 5; then it passes toY theI bearing surface 2, preferably following an inclined outward direction, as at 8, so that the Vlower edge 9 thereof is substantially under the upper edge 3; ,Y
Similarly the side having the recess therein leaves the edge l0, .opposite to the above mentioned edge 3, of the wearing surface l on a convex circular are 11, leaving said surface l at a right-angle therewith, and
passes inward-fon said curved line l1 until faces 4 and llwarealso in contact. `Also the surface 1B is made at the same' angle as the surface 7 4 so that whenthey touch they will contact along a wide surface. The shoulder and 13 .will come in vcontact with each other before the surfaces 4 and 11 meet (see leftion I13 -is however veryslightlyy raised relatively 4to the said line 7 so that the two' surfaces 7.
hand of Fig. 1,)fandalso the surfacel is slightlynarrower than the surface?Y Then 1 the surfacer14 joins theA end of the surface l'with the `side 2, being'parallel .with 'but slightly separated from the side 78, `above described, and forming anobtuseangle 15 with :the said side 2. This angle 15V is almost under the angle 10 but is very slightly undercut therefrom. The sides 13 and 14k join in an angle 1G and this angle projects outward from the edge 10 a distance substantially equal to the, distance that the curvev which are substantially as wide as the present tongue-and-groove construction, but that each said part extends out only one-half its Vtotal width and the boards are undercut only one-half the amount of the present groove and that therefore all the parts of the joint are stronger than iii the tongueand-groove construction. The lip 5 extends out only one-half as far as a tongue and it cannot be readily split from the board because its upper surface extends on a curve to the wearing surface 1 of the board,`thus forming a root of substantially twice the thickness of the usual tongue, while the undercut side-7 is so slight as to be substantially no weaker than the solid board: the recess overhang at 10 is only one-lialf the overhang of the parts forming the ordinary groove and the depth is substantially the same, while its shape forms a cantaliver ably stronger, both under load and in resistance to damage, than the tongue-andgroove joint. Also it must be observed that this board can be cut from about zlinch less width of stock than the corresponding size of tongue-and-groove construction, thus makinga great saving in material thereover. f
A oor islaid by first nailing one board down, lip edge out, driving the nails 17 on aninclined line (Fig. 3) through the concave surface 4:. Then the shoulder 13 ofk the next board is inserted under the lip V5 thus nailed. The said shoulder engages the lip before the board is forced home into position (Fig. 1) and then the board is thus forced into position and nailed as above. Now, the slight incline to the surfaces 7 and 13 has been such as to put the parts under strain when the boards are forced into contact at their edges 3 and 10', the shoulder 13 supporting the lip 5 and the surface 4 of the lip 5 supporting the cantaliver 11, so that the joint between the boards is Ano weaker between supports than are the boards themselves, hence there will be no vertical motion between the boards when loaded between the supports since they are eectually interlocked in tight contact with each other. lf the lip 5 or the shoulder 13 should become swollen by dampness before *1 laying,
then the new board is inserted by tipping its edge as shown in Fig. 4L. 1f the boards shrink after laying7 the joint will be stronger andV stiffer than the tongue-andgroove because the surfaces 7 and 13 will remain in contact throughout their length but with slightly less width, so that the lip edge will be supported by the recess edge of the adjacent board, but there will be a slight motion permitted if the greater strain is on the recess edge of the board, though even then the motion will be no greater than occurs in the usual tongue-andgroove boards at present in use.
An additional advantage on my improved boards is found in the fact than when they are bundled, as shown in Fig. 5, the wearing edges 3 and 10, which it is important should be kept in perfect condition, are protected byy integral projections, 5 and 16 respectively, which prevent any contact with said edges to damage them. This feature is not found in the tongue-and-groove form since the edge in which the groove is made has no integral projection to protect it from dam- Although flooring has been mentioned throughout the above description it is to be understood that I do not confine myself to flooring but to any form of boards 'i Having described my invention, what l claim as new is:
1. A lock joint for flooring and the like u comprising in combination a wooden member having an outwardly and downwardly inclined surface leading from the top surface thereof, said inclined surface being adapted to receive a holding nail, a substantially horizontal surface forming with said inclined surface a projecting lip, said substantially horizontal surface, however being` inclined somewhat downwardly and inwardly, a third surface connecting said substantially horizontal: surface with the underside of the member, said third surface and said substantially horizontal surface forming a substantial recess beneath said lip, and a second member having surfaces compleinental to said .first mentioned and said second mentioned surfaces, a recess complemental to said lip, and a lip for projecting into the recess beneath said first Vmentioned lip, the substantially horizontal surfaces of the two members wedgingjtogether to firmly hold the second member against the support, the lip on said second member being of materially less length than the recess in said tends from the edge of the wearing surface the remainder of said side surface extending outward from the inner end of said undercut on an inclined line to the bearing surface of said strip; and having the opposite side surface complementarily formed.
3. A lock joint for flooring and the like comprising in combination a wooden member having an outwardly and downwardly inclined surface leading from the top surface thereof, said inclined surface beingA adapted to receive a holding nail and forming a slightly extending lip, said lip terminating in a narrow vertical surface near the center of the edge of said member, the underside of said lip being undercut on a downwardly inclined line extending inward. from said vertical surface, a third surface extending from the inner end of said undercut to the under side of the member and thusI forming a recess beneath said lip, and a second member having surfaces complemental to said first mentioned member except as to said central vertical surface of said lip, and said second mentioned member having a lip projecting into said recess but being materially shorter than said recess, whereby a iirm wedging engagement is obtained between the two members irrespective of swelling.
4L. A lock joint for flooring and the like comprising in combination a wooden member having an outwardly and downwardly inclined surface leading from the top surface thereof, said inclined surface being adapted to receive a holding nail, a substantially horizontal surface forming with said inclined surface a projecting lip, said substantially horizontal surface, however, being inclined somewhat downwardly and inwardly to form a wedging surface, a third surface connecting said substantially horizontal surface near the under side of the member', said third surface and said substantially horizontal surface forming a recess beneath said lip, said substantially horizontal surface extending inwardly a greater distance than said first mentioned surface extends outwardly, and a second member having surfaces complemental to said first mentioned and said second mentioned surfaces, a recess complemental to said lip, and a lip for projecting into the recess beneath said iirst mentioned lip, the substantially horizontal surfaces of the two members wedging together to iirmly hold the second member against the support, and the lip on said second member being of materially less length than the recess in said first mentioned member whereby a strong wedging engagement is insured irrespective of swelling.
JAMES W. GRAY.
Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents Washington, D. C.