US2109043A

US2109043A - Door threshold

Info

Publication number: US2109043A
Application number: US41076A
Authority: US
Inventors: Cecil B Davis
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-09-18
Filing date: 1935-09-18
Publication date: 1938-02-22
Anticipated expiration: 1955-02-22

Description

7 Feb. 22, 1938.

C. B. DAVIS Filed Sept. 18, 1955 2 Sheet-Sh aet 1 W mm. k i H w .i

41 J, Q P 0 g 3 Arm Z 157%? W y a 2 4 2 5 A O w 1 64 Feb. 22, 1938.

DOOR THRESHOLD Filed Sept. 18, 1935 2 Sheets-Sheet 2 Patented Feb. 22, 1938 UNITED STATES PATENT OFFICE 4 Claims.

My invention relates to improvements in door thresholds. As at present constructed, the door is designed to fit closely to the floor for this purpose but this results in the door, as it is opened, dragging and striking rugs or carpets on the floor. With this in mind, it is the main object of my invention to provide a means for automatical- -ly sealing or closing up the space below a door as the door is closed.

Another object is to provide a device of this kind, including operating cam blocks secured to the door frame side at the floor line and a threshold plate pivotally mounted by one edge along the bottom of the door and spring set to normally lay flat along the bottom of the door, the free edge of the plate being adapted to engage one of the cam blocks as the door closes and swing down against the floor and to engage the other cam block as the door opens and swing back up beneath the door.

With these and other objects in View, the iiivention resides in the novel construction and arrangement of parts as hereinafter fully set forth and claimed, reference being had to the accompanying drawings, wherein:

Figure 1 is a fragmental elevation of a door and associated parts, the door being closed and provided with my invention.

Figure 2 is an enlarged section along the line 2-2 in Figure 1, showing the threshold plate drawn upward clear of the floor as the door is about to be closed.

Figure 3 is a view similar to Figure 2, showing the door closed and the threshold plate engaging the floor.

Figure 4 is an inverted plan view of the door, showing the grooves and sockets necessary in the bottom edge of the door to mount my invention.

Figure 5 is an enlarged inverted plan view partially broken out and showing my invention mounted on the door.

Figure 6 is a fragmental vertical section through the bottom of the door showing the threshold plate and one of the springs.

Figure '7 is a fragmental perspective view of the lower side portion of the door frame showing the mounting of the cam blocks, and

Figure 8 is an enlarged, fragmentary, sectional view taken on the same plane as Figure 6.

Referring now with more particularity to the drawings, the reference character A designates a door of any conventional form hinged at B in the frame C. Ordinarily, the bottom D of the door would be disposed or arranged to just clear the floor E so that the door could close the space in the frame C but, as aforesaid, the door would then have a tendency to drag on the floor and to drag up carpets or rugs spread on the floor.

In accordance with my invention, the door A is cut short or hung high enough in the frame to provide a substantial clearance space 8 between the door and the floor E, as shown, and my auto matic threshold device or assembly designated generally at 2 is arranged to close this space when the door is closed. The bottom of the door is provided with a groove 3 extended from one edge to the other of the door adjacent what is hereinafter termed the rear side i of the door, rear referring here 'to the trailing side of the door as it closes. At spaced points the door is cut out deeper and laterally to provide spring wells or seats 5 and additionally at the free edge of the door a notch 6 is cut communicating with the aforesaid groove 3. Preferably the groove 3 is uarter-round in section or end View as shown in Figures 2 and 3 to avoid weakening the adjacent rear or trailing side of the door as will be understood.

An elongated mounting plate I is mounted along the bottom of the door by screws 8 and extends at one edge 9 partially across the groove 3 and has a narrow rib or web I turned inwardly or upwardly into the groove near its frontal edge as shown. The threshold plate II is also of elongated form wider than the plate 1 and is preferably slightly arcuate in cross section (Figures 2 and 3) so as to lay fiat over the plate I as shown. A bead or U-shaped roll I2 is formed along the rear edge of the plate H, is stiffened by a wire or rod l3 soldered in its bight and is turned inwardly and upwardly into the groove 3 along the rear edge 9 of said mounting plate I. The frontal edge I4 of the threshold plate ll then overlies the frontal edge of said mounting plate. The plate ll extends clear across the bottom of the door and across the notch 6.

Bow leaf springs l are provided and are disposed freely in the spring wells 5 in the door, each spring with one end 56 hooked over the rib ill on the mounting plate and the other hooked end I! hooked over the free edge I 8 of the roll 52. The springs l5 are tensioned to normally spring together at their ends and, engaged as shown and described with the parts, hold the threshold plate ll tightly up against the door and with the roll 12 held tightly against the mounting plate edge 9. Then the threshold plate ll may be swung downward at its free edge M and as the roll l2 moves up over the edge 9 of the mounting plate 1, the springs will also act to continue this swinging movement of the plate i i.

A substantially triangular cam block it] is secured by a screw 20 to the side of the door frame C adjacent the door stop F and has one point 2! turned out from the stop at a height just nicely to enter the notch 6 in the door A as it closes, the point thus striking above the edge I4 of the threshold plate H and the arcuate face 22 of the cam block guiding and swinging the plate down against the floor E, as will be apparent in Figures 2 and 3. When the free edge M of said plate ll strikes the. floor, the plate stands at an angle as shown due to its being wider than the height of the space I between the door and floor, and of course this space is now closed while the door is closed. A rounded, substantially semicircular or half-round cam block 23, is also secured by a screw 24 to the door frame side outwardly of the aforesaid cam block i9 and spaced therefrom so that the. threshold plate ll may swing down as described in the space 25 between these blocks. Now as the door is opened the plate H strikes the rounded face 2% of this cam block 23 and is raised thereby, and the springs l5 snap the plate back up against the bottom of the door opening the space i, so that the door may swing freely open and clear the floor E by a good margin.

The above. action of the plate i l in closing and opening the space between the door and floor is now to be entirely automatic and positive, and the clearance space is only closed when needed, that is, when the door itself is closed.

While I have herein set forth a certain preferred embodiment of my invention, it is understood that I may vary from the same in minor details, so as best to construct a practical device for the purpose intended, not departing from the spirit of my invention and within the scope of the appended claims.

I claim:

1. In a device of the ln'nd described for mounting upon a conventional assembly of upright door frame and door hingedly mounted therein for horizontal movement, there being a groove formed along the bottom edge of the door, the groove being expanded laterally at spaced intervals to form spring seats, a mounting strip secured along the bottom edge of the door partially over the forward portion of the groove, an upstanding rib extending along the mounting strip and within the said groove of the door, a threshold strip disposable in a raised position in substantial parallelism with the mounting strip and disposable in a lowered position, the threshold strip being formed with a U-shaped roll along its predetermined rear edge with the bight of the roll extended into the door groove over the rear edge of the mounting strip and having a bearing thereon, bow-springs mounted freely within the spring seats of the door groove. and engaging at their ends the said rib and roll of the mounting and threshold strips, the spring ends in engagement with the roll being below the other spring ends when the strips are in substantial parallelism and so disposed that the springs will be moved so that their bias is reversible, to hold the threshold strip in either the raised or lowered position, means for lowering the threshold strip as the door is closed, and separate means for raising the threshold strip as the door is opened, the said threshold strip fulcruming upon the rear edge of the mounting strip under the action of the said springs.

2. In a device of the class described for mounting upon a conventional assembly of vertical door frame having a door hinged therein for opening and closing horizontally, the door having a groove formed along its bottom edge, the groove being expanded laterally at spaced intervals to form spring seats, a strip-like mounting plate secured to the bottom edge of the door and partially over the forward side of the said groove, an upstanding inwardly turned rib on the mounting plate, the said rib being disposed within the said door groove, a strip-like threshold plate having a U- shaped roll along its predetermined rear edge, the said threshold plate being disposed along under the mounting plate with the bight of the roll disposed within the door groove and having a fulcrum bearing upon the rear edge of the mounting plate at the angle formed by the juncture of the roll with the plate, said threshold strip being disposable in a raised position in substantial parallelism with the mounting strip and disposable in a lowered position, bow springs mounted within the spring seats of the door groove and engaging at their ends the said rib of the mounting plate and the depending flange of the roll of the threshold plate, the spring ends in engagement with the. roll being below the other spring ends when the strips are insubstantial parallelism and so disposed that the springs will be moved so that their bias is reversible, whereby.

the threshold plate may be snapped into either its raised or lowered position and there held, the said door having a notch formed in its lower free corner in cooperative alignment with the threshold plate, a triangular cam block secured to the door frame at its lower end and adapted to enter said door notch as the door is closed and engage and guide the threshold plate downward, and a complemental rounded cam block secured to the door frame in spaced relation to the triangular block and adapted to engage the threshold plate and raise same as the door is opened.

3. A device. of the class described comprising a mounting strip, a threshold strip disposable in substantial parallelism therewith and arranged to pivot intermediate its side edges on one side edge of the mounting strip, cam means to initiate operation of said threshold strip, contractile spring means engaging said mounting strip and engaging said threshold strip on opposite sides of the pivotal axis of the threshold strip, the zone of engagement of the contractile spring means with the threshold strip when the. strips are in substantial parallelism being below the zone of engagement of the contractile spring means with the mounting strip, whereby the spring means will urge the strips together when in substantial parallelism and the spring means will be moved so that the bias is reversed to urge separation of the strips when they are out of sub-stantial parallelism.

4. A device of the class described comprising a mounting strip, a threshold strip disposable in substantial parallelism therewith having a raised hook-end portion engaging and fulcrumed on one side edge of the mounting strip, cam means to initiate operation of the threshold strip, a bowshaped contractile spring means at opposite ends engaging the mounting strip and the. free end of said hook-end portion, the zone of engagement of the said spring means with the hook-end portion when the strips are in substantial parallelism being below the zone of engagement of the spring means with the mounting strip, whereby the spring means will urge the strips together when in substantial parallelism and the spring means will be moved so that its bias is reversed to urge separation of the strips when they are out of substantial parallelism.

CECIL B. DAVIS.