Joints and connections – Interfitted members – Clamped members
Reexamination Certificate
1999-04-16
2001-09-18
Browne, Lynne H. (Department: 3629)
Joints and connections
Interfitted members
Clamped members
C403S256000, C403S247000, C411S085000
Reexamination Certificate
active
06290426
ABSTRACT:
BACKGROUND OF THE INVENTION
Channel or U-shape strut is widely used in the construction industry. It is used to form vertical, horizontal or even angular framing. It may be hung from ceilings or attached to or embedded in walls or ceilings. Conventional struts are U-shape or channel shape, and the legs terminate in a rolled or inturned short radius circular fold so that the inturned legs terminate in an inwardly facing edge. The opening of the channel is thus restricted, and the legs are in the form of two continuous hooks. A wide variety of fasteners, hangers or brackets are used to support utilities, such as pipes, conduit, lighting, cable trays, and air conditioning or ventilation duct work, for example.
One of the most common adjustable hanging or supporting devices used is the common threaded rod. To connect the rod to the strut, a strut nut is normally employed. The strut nut has two parallel grooves in one surface which are designed to seat on the parallel inturned edges of the channel legs. The strut nut is usually a machined block rectangular in shape, so that it has a narrow dimension enabling it to be inserted into the channel between the inturned edge legs and rotated 90° to span the edges of the legs. This normally has to be done by hand with the installer's fingers being inserted in the channel and twisting the nut. The nuts are often provided with unwieldy compression springs to push the nut from the bottom of the channel once seated to maintain the grooves on the inturned leg edges. Trying to thread a rod into the nut may compress the spring excessively causing the nut to slip and making the proper insertion of the rod difficult.
In some arrangements, particularly with square nuts, the nuts have to be inserted or threaded into the end of the channel. Square nuts are sometimes used with strut or channel that has a series of holes in the back, with the rod threaded in the nut extending downwardly through the hole. Sometimes the nuts are simply loose in the channel or strut, relying solely only on the weight of the load to keep them in place. Some systems use one kind of nut for the open side of the channel or strut, and another for the other or back of the channel.
A rod can also be secured to a strut using what is known as a hammerhead which seats on the outer turned portion of the strut legs. The rod extends through the hammerhead and through the bottom of the strut. Conventional nuts and optionally washers are threaded to bear against the hammerhead and bottom of the strut, respectively. Proper alignment or adjustment either axially of the rod or along the strut is difficult and time consuming. Final installation is also difficult and time consuming, requiring the positioning and tightening of at least two nuts. If adjustment is required, then loosening, repositioning and retightening are required.
Hammerheads and nuts can be utilized together with a common fastener such as a bolt. Such assemblies are used sometimes to splice strut sections or to act as stops for other type fasteners securing pipe, for example, to the strut. Examples of such assemblies are seen in prior U.S. Pat. No. 4,783,040 to Lindberg, et al.
There is a need for a fastening system which can firmly clamp a length of threaded rod to the strut and support the rod and any load on the strut for full compressive or tensile loading on the rod. There is also a need for a rod-strut connecting system which can easily be preassembled and inserted in the channel for adjustment, both along the strut, or axially of the rod, before being tightly clamped and affixed to the strut.
SUMMARY OF THE INVENTION
A rod connector is employed for channel shape strut of the type having legs with inturned edges. The connector includes an internal head with a central plate having a threaded hole adapted to receive a threaded rod. The hole is extruded from the plate and has rolled internal threads matching the external threads of the rod. When the rod is threaded in the hole, it is maintained perpendicular to the plate.
The internal head includes, along parallel edges, upturned edges designed to seat under the inturned edges of the strut legs. Opposite parallel edges of the internal head are provided with angular symmetrical flanges having sloping edges adapted to pilot and center the internal head within the strut. Projecting upwardly from the center of the flanges are flange extensions which each include a pressed out projection or pintle. The pintles include sloping or wedge exterior surfaces.
The external head is also formed from a plate which includes a centered slot extending transversely of the strut and which accommodates the threaded rod. The external head includes stiffening flanges with the lateral flanges parallel to the slot and transverse the strut including seats for centering the external head on the inside surfaces of the external turned portion of the strut legs. This enables the external head to be centered and seated easily when clamped, and yet be free to slide or move when unclamped. The lateral flanges also include flange extensions, each of which has a slot. The flange extension slots are parallel to each other. The flange extensions of the external head telescope over the flange extensions of the internal head, and the sloping or wedge surface slightly separates the slotted flange extensions of the external head until the projections or pintles snap into the slots. The two heads are then connected for relative pivoting movement and limited separating and closing movement. The limitation of the separating movement is the length of the slots in the external head flange extensions. With the rod secured to the internal head and projecting through the slot in the external head, the relative pivoting movement is limited by the length of the transverse slot in the external head central plate.
In assembly, a lock nut may be threaded on the end of a threaded rod, allowing room to the rod end. The assembled head is then threaded on the rod end, with the rod passing through the external head slot and being threaded in the threaded hole in the inner head. The assembly may then be inserted in the strut simply by rocking the rod to one side, enabling the inner head to be inserted through the strut opening and then rocked back to a centered position. The flange edge on the internal head pilots and centers the head inside the strut. The limited rocking movement between the two heads enables this ease of insertion without interference. The rod may be adjusted axially to bear against the bottom of the strut or go through a hole in the bottom of the strut. With the lock nut loose, this may be accomplished simply by turning the rod. With the lock nut loose, the assembly may also slide along the strut to any desired location.
When in the desired location, the lock nut is simply tightened. The pilot flanges on the inner head, and the seats on the flanges of the outer head ensure that the two heads properly seat on and grip the inturned edges of the strut legs, and the external turned portion, respectively. The clamping and proper seating is obtained with a few turns of the lock nut. When clamped, substantial loading of the rod with respect to the strut is obtainable in either axial direction.
To the accomplishment of the foregoing and related ends, the invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.
REFERENCES:
patent: 2767609 (1956-10-01), Cousino
patent: 4460299 (1984-07-01), Kowaiski
patent: 4575295 (1986-03-01), Rebentisch
patent: 4783040 (1988-11-01), Lindberg et al.
patent: 4784552 (1988-11-01), Rebentisch
patent: 4830531 (1989-05-01), Condit et al.
patent: 4950099 (1990-08-01), Roellin
patent: 5375798 (1994-12-01), Hungerford
patent: 5489173 (1996-02-01), Hofle
patent: 5628597 (1997-05-01), Chudo
Huwer Stefan Walter
van Gijsel Gerardus Emanuel Cornelius
Browne Lynne H.
Erico International Corporation
Malcolm Tomlyne A
Renner Otto Boisselle & Sklar
LandOfFree
Threaded rod and strut connector and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Threaded rod and strut connector and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Threaded rod and strut connector and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2487680