US2263895A

US2263895A - Resilient floor

Info

Publication number: US2263895A
Application number: US299002A
Authority: US
Inventors: Larsen Bjorn Valeur
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-10-12
Filing date: 1939-10-11
Publication date: 1941-11-25
Anticipated expiration: 1958-11-25
Also published as: GB578294A; ES174655A1; DK59329C

Description

Nov.- 25, 1941. y I B. v. LARsl-:N 2,263,895

RES ILIENT FLOOR N v NTO n: Broan VHLEUR LnnsEN,

HTTORNEAI NOV. 25, 1941. B v LARSEN 2,263,895

RESILIENT FLOOR Filed Oct. l1. 1939 2 Sheets-Sheefl 2 E; $3 @i E:

l N VENTOR: BJORN VHLEUR LHRSLN miv/iw@ g w Patented Nov. 25, 1941 UNITED STATES PATENT OFFICE Application October 11, 1939, Serial No. 299,002 In Denmark October 12, 1938 4 Claims.

The invention relates to a resilient or yielding oor structure. For several uses it is desirable that the floor should possess a certain' resiliency. Thus it is well known that oors for gymnastic exercises and the like supported by an ordinary tier of beams are far more pleasant to use and more serviceable for the contemplated use than floors resting directly, or with oor strips as intermediate members, on a solid concrete base or a concrete floor slab. This recognition has resulted in the provision of self-supporting tiers of beams, or tiers of beams supported on girders, even for gymnastic-exercise floors in the ground story when no basement proper is provided. Such a tier of beams, however, requires a rather great thickness, and the resiliency produced will be highly irregular, as in the vicinity of the supports of the beams on the walls or girders it will be quite negligible, and only at the central parts of the beams it will have any considerable mag nitude. Another drawback is that the resilient deflection produced by jumping or the like at one point of the floor will propagate itself through the iioor beams to the entire floor surface or a large part thereof, which is disagreeable and frequently injurious to other symnastic exercises performed at the same time, such as equilibristic exercises.

It needs hardly to be pointed out that the resiliency of the tier of beams is a great nuisance to the use of any rooms situated below and having their ceiling supported by the tier of beams.

In order to attain a tolerably uniform resiliency in thefloors of sporting halls and the like where the floor is resting on floor strips on a concrete base, it is known to support the floor strips, or the timber supports for the latter, on spiral springs of steel. As the first cost of the latter is rather high, relatively few and strong springs are generally provided, which precludes a narrow localization or limitation of the resilient deflection of the floor, and the attainment of a suitably large resilient motion. ,On such floors supported on steel springs there will consequently be the same unpleasant propagation of vibration over a larger floor area as mentioned above.

A feature of great importance in resilient oors is, besides the magnitude of the resilient deflection, i. e. the magnitude of the oscillation amplitude, also the magnitude of the period of oscillation, .as a too long period of oscillation may have a Very unpleasant effect. In the case of the said known spiral springs and the same elasoscillation can only be altered by varying the magnitude of the mass that is set into motion, and in practice we are here entirely confined to the quantity of material determined b-y the requirements as to Strength that have to be lled by the structure, in such a manner that any variation of the oscillation period that may be required cannot be effected. As further the said steel springs, when left to themselves, will perform mainly undamped oscillations, in such a manner that the damping of the resilient motion will mainly be effected through the remaining floor structure, the said springs may easily cause annoying vibrations in thefloor.

The invention provides a resilient arrangement giving a quite uniform and strictly localized resiliency of any desired magnitude, while at the same time the above mentioned drawbacks of the known arrangements are avoided, and it is fur- ,ther possible to produce such a floor considerably cheaper than by the use of the described steel springs. vBy a suitable selection of materials for carrying out the invention, the advantage may be attained that the device can be made by any ordinary carpenter, so that one will be entirely independent of spring factories and the like.

Theinvention is especially intended to be used in halls for gymnastic exercise, tennis halls and other sporting halls as well as dancing-rooms, but it may of course be used for any floor in which a resiliency of the kind described is desirable.

According to the invention, resilient supporting members are inserted between the supporting floor beams or concrete slab and the floor strips on which the ooring is resting directly, the said resilient members consisting of bar-shaped members disposed mainly parallel to the flooring and at some distance from each other, which barshaped members, owing to the weight of the floor acting at right angles to their longitudinal direction, are exposed to bending in the same manner as a beam, and are situated at such mutual distances, and are resting on supports disposed in such a manner, relatively to the point or points at which the weight of the oor is transmitted to the bar-shaped member, that the local resilient deection produced by the elastic bending ported by the latter will be mainly of the same magnitude for the same load, at any point of the resiliently supported floor.

As a rule it will be preferable to use supporttic compression for a given load, the period of ing members that are more flexible in a direction of the supporting members and the floor sup-` at right angles to the floor than in a direction parallel thereto.

According to the invention, the resilient member may be made from any elastic material, for instance a steel bar of rectangular cross-section, but in general it will be preferable to use wooden planks which as beams supported at their ends receive the pressure from the floor surface at their centre or, for instance, at points one third from the ends. According to the invention, the individual plank may have varying cross-section, and may for instance be pointed or have its thickness decreasing towards the ends, in order to attain a greater deflection than with a uniform cross-section, al1 with the same maximum fibre stress.

The drawings show, by way of example, three different constructions of a resilient floor according to the invention, in which construction simply supported planks, partly with varying cross-sections are used as resilient supporting members for the floor surface.

Fig. 1 shows, in plan view, the floor strips resting on resilient plank supports disposed on a .concrete floor,

Fig. 2 a section along the line II-II in Fig. 1,

Fig. shown in Fig. 1, but with resilient planks of varying cross-section,

Fig. 4 a section along the line IV-IV in Fig. 3,

Fig. 5 an arrangement similar to the one shown in Fig. 3, but with the plank supports of the individual floor strips partly displaced, relatively to each other.

In Figs. 1 and 2, I indicates the oor strips to which the floor boards (not shown) are nailed, 2 are wooden blocks which rest on a concrete oor 3, and form supports for planks 4 carrying, at the centre of their span, the above mentioned floor strips I. In order to increase the resiliency and to prevent the transmission of the resilient deflection to the adjacent spans, the planks 4 are partly cut through by saw-cuts 5, centrally over the supports. Similar saw-cuts may be made in the floor strips I above the planks 4,

in order to prevent the propagation of the resilient motion through the floor strips, but this will generally not be necessary. Fig. 3 shows a construction in which the floor strips I are supported by planks 6 tapering towards the ends g and resting by means of blocks 2 on the concrete base 3. On the said base, under the centre of the planks 6, a strip I is provided, in order to prevent excessive stresses in the planks 6, due for instance to a dense crowding of people on the floor, or an abnormally forceful impact, as the plank 5 will then rest directly on the strip I which thus transmits the excess load to the concrete base 3. Instead of the strip 1, blocks of for instance caoutchouc may be used, and instead of resting on the base 3, the said blocks may be attached to the bottom face of the plank 6.

In the arrangement shown in Figs. 4 and 5, suitable resiliency conditions for gymnastic use are attained by the use of 11A, x 5" (3.2 x 12.5 centimetres) boards as resilient planks, and 2 x 5 (5 x 12.5 om.) scantlings as floor strips, as the length of the resilient planks and the mutual distance of the floor strips is about 28 (0.80 m.) and the distance between the resilient planks is about 3'3" (1 m.), which in connection with a floor of boards 1" (2.5 om.) thick gave a resilient deflection of about (1.5 cm.) in the case of jumping and similar exercises.

3 an arrangement similar to the one When it is desired, in View of the magnitude of the deection or the oscillation period, to give the resilient planks a larger span than the distance between the floor strips I', the planks may be staggered, relatively to each other, as shown in Fig. 5, in which the floor strips I are supported by resilient planks 8 the free span of which is about twice the distance between the oor strips. The planks 8 rest on blocks 9 disposed on the concrete floor 3.

By placing the resilient planks obliquely, relatively to the direction of the floor strips, the free span of the planks may be rendered larger than the span corresponding to Fig. 5.

In order to avoid creaking due to friction occurring between the parts during the resilient deflection, a layer of' asphalt felt or the like may be inserted between al1 the contacting surfaces, and in order to allow the parts to move freely, relatively to each other, during the resilient deiiection, a suitable play may be provided at the nailed connections or the like by which the parts may be interconnected.

By a suitable selection of the dimensions and span of the planks, the magnitude of the resilient deflection and the period of oscillations may be varied, independently of one another and entirely as required. As the plank material possesses a rather high damping ability, the oscillations which owing to the special construction of the structure are largely localized will soon become damped, in such a manner that not even local vibrations will be produced to any appreciable extent.

It is further possible to adjust the rigidity of the floor strips and the floor boards in such a manner, relatively to the resilient support, that the resiliency of the oor will be mainly the same, directly above the points of support of the floor strips on the resilient supports, as well as in the spaces between the latter.

Obviously, the invention is not limited to floors disposed on top of a continuous concrete base, but it may also be used to advantage when the floor is supported by a tier of beams or the like, and here the invention involves the advantage that violent vibrations are not propagated as such to the tier of beams, and consequently the above mentioned inconveniences to rooms situated below cannot occur. Finally, it is to be noted that the resiliency, instead of being created by simply supported planks, may also for instance be provided by planks with cantilever ends, which then act as cantilever springs, and in general the resiliency according to the invention may be produced by any member exposed to elastic ilexure perpendicular to its longitudinal direction.

Having thus described my invention, what I claim is:

1. A resilient floor construction supported on a substantially rigid base and comprising a plurality of resilient members disposed in parallel spaced relation on said base, floor strips disposed in spaced parallel relation on said resilient members and extending transversely thereof in position to support floor boards in parallel relation to said resilient members and supporting blocks disposed beneath the resilient members at points between the oor strips.

2. A resilient floor construction supported on a substantially rigid base and comprising a plurality of resilient members disposed in parallel spaced relation on said base, floor strips disposed in spaced parallelI relation on said resilient memepesses bers and extending transversely thereof in position to support oor boards in parallel relation to said resilient members, supporting blocks disposed beneath the resilient members at points approximately intermediate the distance between said floor strips, each of said resilient members being partially severed transversely at the side thereof opposite each of its supporting blocks thereby to increase its resiliency and prevent transmission of the resilient deection to adjacent members.

3. A resilient floor construction supported on a substantially rigid base and comprising a plurality of resilient members disposed in parallel spaced relation on said base, floor strips disposed in spaced parallel relation on said resilient members and extending transversely thereof in position to support iioor boards in parallel relation to said resilient members, supporting blocks disposed beneath the resilient members at points approximately intermediate the distance between said floor strips, each of said resilient members being partially severed transversely at the side thereof opposite each of its supporting blocks thereby to increase its resiliency and prevent transmission of the resilient deiiection to adjacent members, and cushioning strips disposed below the resilient members and extending transversely thereof in underlying parallel relation to said oor strips.

4. A resilient iioor construction supported on a substantially rigid base and comprising a plurality of resilient members disposed in parallel spaced relation on said base, iioor strips extending in spaced parallel relation transversely of r said resilient members and each supported on alternate resilient members, and supporting blocks disposed between said resilient members and said base, the resilient members being tapered in opposite directions toward their ends at opposite sides thereof.

BJRN VALEUR LARSEN.