Patent Application
20060000174
U.S. Pat. No. 4,388,016 issued Jun. 14, 1983 to Bertram J. Levey is directed to an expansion joint and seal assembly for use with concrete structures. The type of expansion joint and seal assembly described in the Levey patent, which patent is incorporated herein by reference, functions properly as an expansion joint for concrete structures such as roadways, sidewalks, driveways, runways and other concrete structures.
Certain improvements have been sought in concrete expansion joints, particularly of the type described in the Levey patent. Such improvements include providing an expansion joint which is easy and economical to fabricate and does not require the complex structural features and assembly procedures required of the Levey expansion joint. There has also been a desire to provide an expansion joint which has an elastic memory which will allow the side frames or extension members to separate and remain connected to the respective sections of concrete to which they are adhered and to move back and forth with the separated sections of concrete while a seal is maintained therebetween. Still further, improvements have been sought in expansion joints of the general type described wherein the opposed side frames or extension members remain temporarily connected to each other, particularly at their adjacent distal ends, prior to placement in the concrete structure but at the same time are capable of separating from each other once in place and required to begin their function as part of an expansion joint.
Accordingly, in view of the problems associated with prior art expansion joints and the desire to provide the improvements indicated hereinabove, as well as other improvements deemed desirable in concrete expansion joints, the present invention has been developed.
The present invention provides an improved concrete expansion joint and seal assembly which is relatively uncomplicated, easily fabricated and forms a permanent seal between separated sections of concrete.
In accordance with one aspect of the present invention, a concrete expansion joint and the like is provided which is formed of opposed side frame or extension members which are interconnected by a seal member which is flexible, has an elastic memory and is prejoined to the side frame members by coextruding the seal member and the side frame members of suitable materials including preferably, a thermoplastic elastomer and polypropylene, respectively.
In accordance with another aspect of the present invention, a concrete expansion joint is provided which is coextruded with an elastic memory of a seal member so that the side frame or extension members are biased to remain connected to separated sections of concrete so that the expansion joint functions properly when the separated sections of concrete move toward and away from each other during normal expansion and contraction due to thermal conditions or changing soil conditions, for example. In this regard, the coextruded expansion joint assembly is provided with means for holding, at least temporarily, the side frame or extension members together so that the expansion joint may be inserted into poured concrete in accordance with normal practice for placing expansion joints in their working positions. The side frame or extension members may be secured together by a double sided adhesive tape member, by a relatively weak adhesive or by providing the adjacent side frame members with cooperating hook and latch portions whereby the side frame or extension members are at least temporarily tightly secured to each other and are substantially contiguous with each other for purposes of placing the expansion joint in its working position. The side frame members are substantially planar but may be formed with opposed shallow bowed or curvilinear portions to assure that their distal ends form a so-called knife edge or chisel point to facilitate insertion in poured concrete.
Those skilled in the art will further appreciate the above-mentioned advantages and superior features of the invention together with other important aspects thereof upon reading the detailed description which follows in conjunction with the drawings.
In the description which follows like elements are marked throughout the specification and drawing with the same reference numerals, respectively. The drawings are not necessarily to scale and certain features may be shown in somewhat schematic or generalized form in the interest of clarity and conciseness.
Referring to
Referring further to
Side frame member 22 includes a generally planar plate-like part 26 from which project spaced apart transverse flanges 28, 30 and 32, together with a somewhat chisel or knife blade-shaped flange part 34 defining the distal end of the side frame member 22. As illustrated throughout the drawings, the flanges 28 and 30 extend at acute angles from the plate part 26 and toward each other so as to define a channel 36. In like manner, the flange 32 and the somewhat chisel-shaped distal end part 34 also extend from the plate part 26 toward each other at acute angles to define a second channel 38. Accordingly, the channels 36 and 38 have inwardly turned or reentrant flange portions defining these channels so that when the side frame member 22 is immersed in flowable concrete it fills the channels and when such concrete hardens the side frame member are securely fastened thereto.
Side frame member 24 is substantially a mirror image of side frame member 22 and is characterized by a generally planar plate part 40 and spaced apart flanges 42, 44 and 46, together with a distal end chisel-shaped part 48 which is a mirror image of the chisel-shaped part 34. As with the side frame member 22, opposed channels 50 and 52 are defined by the flange portions 42 and 44 for flange 50 and flange portions 46 and chisel part 48 for the channel 52. Side frame members 22 and 24 have opposed, shallow, bowed or curvilinear parts 37 and 39 between the opposite ends of the side frame members to facilitate and maintain the side frame members tightly contiguous with each other at their distal ends to facilitate insertion in unhardened concrete or the like. Accordingly, the chisel-shaped parts 34 and 48 form a relatively fine chisel point or knife edge 56 which facilitates insertion of the expansion joint and seal assembly 10 into freshly poured concrete, again generally in accordance with the teaching of U.S. Pat. No. 4,388,016. However, those skilled in the art will appreciate that the expansion joint and seal assembly 10 is advantageous in that by providing the side frame members 22 and 24 permanently bonded to the flexible seal member 12 at fabrication a more efficient and inexpensive assembly is provided in accordance with the method of manufacture and the bond between the side frame members 22 and 24 and the seal member 12 is strong and permanent thanks to the coextrusion of these three members.
Still further, the invention contemplates the provision of means for securing, at least temporarily, the side frame members 22 and 24 to each other, which means may comprise an elongated strip of double sided adhesive tape, generally designated by the numeral 54 in
Referring briefly to
Referring now to
However, since the side frame members 22 and 24, as well as the side frame members 22a and 24a are at least slightly flexible, once the expansion joint and seal assembly 10b is placed in poured concrete, the concrete has filled the channel portions 36, 38, 50 and 52 and the concrete has hardened, then when the concrete sections separate, the side frame members 22a and 24a will become disconnected at their distal ends to remain connected to the separated concrete sections. After extrusion of the expansion joint and seal assembly 10b, the side frame members are placed contiguous with each other, as illustrated in
As mentioned previously, the position of the side frame members 22a and 24a shown in
Referring briefly to
Referring briefly to
Those skilled in the art will appreciate the advantages and superior features of the embodiments of the invention described herein. The methods of manufacture and use are believed to be readily understandable to those of ordinary skill in the art. Corrosion resistant and coextrudable materials may be used to fabricate the seal member 12 and the side frame members 22, 22a, 24 and 24a other than those described herein.
Although preferred embodiments have been described those skilled in the art will appreciate that substitutions and modifications may be made without departing from the scope and spirit of the appended claims.
