US 3648425 A
A device including threadably engaged telescoping members adapted to be extended into engagement with spaced apart nonmetallic floor joists. One end of the device has two pointed projections for penetrating a joist and limiting the member from rotating while the other end has a single pointed projection for penetrating a joist but permitting the member to be rotated to extend the device.
Claims available in
Description (OCR text may contain errors)
United States Patent Bolton 1 Mar. 14, 1972 [541 ADJUSTABLE BRIDGING DEVICE 474,847 5/1892 Morgan ..52/112 X 2,914,816 12/1959 Lungren  Invenwr- 51652 3,077,009 2/1963 Taber et a1 ..52/632  Filed: May 14, 1970 Primary Examiner-Price C. Faw, Jr. PP N061 37,123 Attorney-Zarley,McKee&Th0mte  us. Cl ..52/632, 52/696, 248/354 5  ABSTRACT  Int. Cl. ..E04c 3/04, E04g 17/06 A device including threadably engaged telescoping members  Field 01 Search ..52/112, 111,632, 317, 291, adapted to be extended into engagement with spaced apart 52 573 9 95, 90; 24 /3 54 S nonmetallic floor joists. One end of the device has two pointed projections for penetrating a joist and limiting the member  Re'erences Cited from rotating while the other end has a single pointed projection for penetrating a joist but permitting the member to be UNITED STATES PATENTS rotated to extend the device.
808,611 12/1905 Miller ..248/354 S 1 Claims, 8 Drawing Figures ADJUSTABLE BRIDGING DEVICE Heretofore wooden braces have been used between floor joists to hold the joists in place and add stability to the joists. The wooden braces would commonly be used in pairs and form an X between the joists. It is apparent that flooring constructed in this manner is expensive, time consuming and unsightly.
The adjustable bridging device of this invention is attractive in appearance, easy to install, and moderate in cost. The bridging involves a pair of threadably telescoping elongated members wherein each of the members at its outer end has at least one pointed projection for penetrating into a wood floor joist. One end has two pointed projections to hold the member in place and limited against turning while the other member has only one pointed projection which permits it to turn and thus extend the bridging device such that the outer ends of the two members are in mating flush engagement with the side surfaces of the joist. A minimum of friction is developed between the one end having the one pointed projection and the floor joist making it easy to rotate the one member for extending the device. The rotation is accomplished by hand and the one member is substantially larger in diameter than the other member. Moreover, the one member has a bore along its longitudinal center which is threaded to receive the threaded end of the other member. The outer annular edge of the rotatable member may be beveled to minimize frictional resistance to the turning of the member by sharp peripheral edges gouging the wooden joist. Another alternative is that the outer end of the rotatable member may have a convex outer surface thereby minimizing the total joist contact area around the pointed projection.
This invention consists in the construction, arrangements and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, specifically pointed out in the claims, and illustrated in the accompanying drawings in which:
FIG. 1 is a perspective view of the adjustable bridging device ofthis invention.
FIG. 2 is a side elevational view of the adjustable bridging device placed in position between a pair ofjoists ready to be extended.
FIG. 3 is a view similar to FIG. 2 but showing the adjustable bridging device extended into mating engagement with adjacent floorjoists.
FIG. 4 is a fragmentary enlarged side elevational view ofthe adjustable bridging device only.
FIG. 5 is a cross-sectional view taken along line 5--5 in FIG. 4.
FIG. 6 is a cross-sectional view taken along line 66 in FIG. 4.
FIG. 7 is an end elevational view taken along line 7-7 in FIG. 4; and
FIG. 8 is a fragmentary side elevational view of an alternate embodiment wherein the rotatable member has a convex outer end.
The adjustable bridging device of this invention is referred to generally in FIG. 1 by reference numeral 10 and is shown in FIG. 2 positioned between a pair of adjacent wood floor joists l2 and 14 extending downwardly from a floor 16.
The adjustable bridging device 10 includes an elongated rod 18 threaded at 20 on its inner end and having an enlarged outer end 22. The outer surface 24 of the outer end portion 22 is flat as seen in FIG. 7 for mating engagement with the flat surface ofthe joist 14 as seen in FIG. 3. A pair of pointed conical-shaped projections 26 are uniformly spaced on opposite sides of the longitudinal center of the rod 18 on the face 24 of the end portion 22 and are adapted to penetrate the wood of the floor joist 14- as seen in FIG. 3.
A rotatable telescopic member 30 substantially larger in cross section than the rod 18 has a longitudinal bore 32 (FIG. 5) threaded to receive the threaded inner end of the rod 18. The member 30 is provided with longitudinally extending knurling including ridges and grooves 34 and 36 uniformly spaced around the periphery of the member 30 (FIGS. 6 and 8). A single pointed conical in shape projection 40 is provided on the longitudinal center of the member 30 such that the member 30 may be freely rotated relative to the member 18 and the joist 12. As seen in FIGS. 4 and 5, the outer end ofthe member 30 includes an annular flat surface 42 around the pointed projection 40 which merges at its outer periphery into an annular tapered peripheral edge 44.
In FIG. 8 an alternate embodiment of the member 30 is shown which includes a convex outer surface 46 around the pointed projection 40 thus providing minimum contact between the outer end of the member 30A and a wooden floor joist 12. The tapered annular edge 44 of the member 30 in FIG. 5 eliminates sharp edges which would tend to gouge the wooden joist l2 and cause frictional resistance to the turning of the member 30 while the convex surface 46 on the member 30A in FIG. 8 also minimizes the frictional resistance possible between the member 30A and a floor joist thus making it easy to rotate the member 30A and extend the bridging device 10 as desired.
In operation it is seen that the bridging device 10 is extended initially to approximately the length of the spacing between the adjacent joists 12 and 14 as seen in FIG. 2. In FIG. 2 the pointed projections 22 on the right end and the single pointed projection 40 on the left end are just touching the wooden floor joists and have not yet penetrated the wood. In FIG. 3 a person has manually rotated the member 30 while the member 18 remains stationary due to the two pointed projections 22 penetrating the wooden floor joist l4 and limiting the member 18 from turning. The member 30 is free to rotate since a single pointed projection is provided on the longitudinal center of the member 30 and it offers little resistance to the rotational movement. It is seen that just a few turns will extend the bridging device sufficiently to maintain the desired pressure on the joists 12 and 14 and the outer end surfaces of the members 18 and 30 will become load bearing very quickly. If it is desired to remove the adjustable bridging device it is simply necessary only to reverse the rotation of the member 30 and the pointed projections 26 and 40 will be withdrawn from the wooden joists l2 and 14 allowing the device to be removed. It is thus seen that either installation or removal of the bridging device may be accomplished in a matter of seconds and that the resulting structure will be strengthened and stabilized in addition to having an attractive appearance.
1. An adjustable bridging device comprising a pair of threadably engaged telescoping elongated integral members having outer ends adapted to engage spaced apart adjacent floor joists, one of said members has an outer end having a plurality of longitudinal outwardly extending pointed projections adapted to penetrate a nonmetallic floor joist and limit the associated telescopic member from rotating, and said other member has an outer end having only a single pointed projection on the longitudinal center of said device whereby it may penetrate a nonmetallic floor joist and allow said associated telescopic member to rotate when said device is being extended, said one telescoping member being a rod having a threaded inner end and an enlarged in diameter shoulder at its outer end, and the other telescoping member being substantially uniform along its length in diameter and substantially equal to the diameter of said shoulder on the outer end ofsaid one member, and having a threaded longitudinal center bore extending the substantial length thereof and terminating short of said outer end and in which said threaded inner end of said one member is received, and said other member having a substantially larger diameter than said one member to provide a hand gripping surface having sufficient leverage to rotate said other telescopic member manually, said other member having a length sufficient to be gripped by a hand and substantially less than said other member, said other member having a knurled outer surface along its substantial length to increase the friction between said surface and the hand of a person manually turning said other telescopic member, said shoulder on the outer end of said one member including only two of member to turn freely relative to a nonmetallic joist in engagement therewith, and the shoulder at the outer end of said one member being flat over its entire surface extending to the peripheral side surface of said enlarged outer end and said two pointed projections extending longitudinally outwardly from said flat surface.