Patent Application
20090049789
The present invention is related to devices for the spacing of structural elements for reinforcing concrete, of the type with disc form where the structural element is located inside and throughout the central axis of the device, and in special, to one of such devices in which the insertion of the structural element is made by a radial opening that goes from the center of the device to one of its ends, with elements to hold and close of the two parts once the structural element in the central axis has been inserted, so that it forms an element or closed circular device, that maintains the steel of reinforcement centered.
In the prior art, devices are described that have functions of separation between constructive elements or between them and some limiting surface. A special case is that to which the present invention goes, where a device serves to distance to a structural element of the walls or surfaces of containment the concrete. Some examples of the developments that are at the moment in the prior art, are described briefly next and must be taken as reference.
Gavin, in U.S. Pat. No. 5,347,787 (Gavin, 1994) describes a device molded in rigid plastic, as a single piece, essentially circular formed, used in concrete constructions as spacer element in the reinforcement bar; it consists of two sections connected in one end to a hinge, and held by a pawl in the other end. The bar subjects in the center of the wheel by means of a pair of seats, located one in each section of the wheel. A column together with one of the sections between the seats and the hinge avoids that the bar slipping.
In U.S. Pat. No. 5,542,785 (Cloud, 1996) it is described a spacer mounted on a lateral bar of a reinforcing cage the spacer includes a pair of wheel members adjustable between themselves—in a rotatable relation, mounted on one of the cage's bars to form the spacer. As the reinforcement cage is coupled and turns along the lateral wall of the well. Coupling with the wall of the drilled well, centers the cage in the drilled well and maintains it in centered position while the well is poured.
In U.S. Pat. No. 6,385,938 (Gavin, 2002) it is described how a pair of curved arms are attached to a body to form an annular seat to support a first diameter of a bar; there is a slit trough the external diameter of the body, which forms a radial entrance path towards the seat; the seat offers a spring movement towards the bar.
In other fields, specifically in that of the elongated elements supports, some documents are found describing interesting developments in the way to fasten circular cross-section elements.
In U.S. Pat. No. 5,118,215 (Freier, 1992) it is described a fastener for tube or duct which includes a plated formed base, a pair of arched segments, two rotatable supports connecting the two segments with the base in an intermediate point in respect of the ends, to divide the segments of a belt in one peripheral internal part and one peripheral external part; serrated tongues coupling between themselves to close with the peripheral ends of the belt, to fit them around the duct or tube. The closing tongues in the external peripheral part of one of the segments, cover a plurality of external teeth and the closing tongues in the external peripheral part of the other segment cover a plurality of internal teeth, in a way that when the closing tongues fit around the duct or tube, the belts are symmetrical with the tube or duct axis supported.
In U.S. Pat. No. 4,214,351 (Wenk, 1980) it is described a staple which securely supports an object to another, as for support a tubing or similar elements with a flexible strap; includes an annular strap with an open end having a pair of members attachable one to another and opposite, located in the open ends. One of the attachable members generally includes a teethed jaw and an internal arm radially spaced defining a entrance. There are a pair of supporting arms located radially between the arms at the end of the jaw and opposite to the entrance.
Application and use of the elements as described in the prior art patents, and subject matter of this invention, date back long time ago, once traditionally this type of circular spacers for foundation piles or walls, or for certain types of walls, are used to be made in one piece, pouring concrete or some melted plastic materials in olds designed ad hoc and habilitated in situ.
Function of this type of accessories has been always to place one of them in one of the circular bars or “brace support”, perpendicular to the bars that constitute the main steel and located longitudinally in the cage or reinforced steel, in a way for the disc rotate when the structure is introduced into the perforation or form, and it can couple with the external wall of the excavated well, in order to the spacer disc center the cage within the excavated well and maintain it in such centered position while the well is poured.
The device subject matter of this invention is an spacer or separator element essentially in a disc form, with a hole or central axis that when it is closed forms a ring or open cylinder whose walls conforms to the geometry of an structural elongated member passing through it; preferably with circular cross-section although it can have any other geometry.
Function of the device of the invention is to separate the structural element in a determined distance to achieve a cover or concrete layer equal to the radial distance between the central axis and the surface of the external ring of the device, or from any other object such as the surface or wall of the perforation or form.
Different to other devices in the prior art, the device of the invention is made in one single piece, injection molded from a plastic resin such as but not limited to high density polyethylene (HDP), and it is formed by two semicircles joined in one of their common ends taking advantage of the properties of the raw material, by means of a flexible integration that interacts similar to a hinge; this one-piece design offers a higher stability and strength as well as an easier installation, with savings on labor and costs because it has up to 20% less raw materials, permits the separation and closing of the opposite ends of the semicircles, which have reception elements that permit their fixation or embrace the structural element when it is introduced through said opening to locate on the central axis of the device, on the reception elements preferably formed as to the structural element profile and located en the central zone of the device; both semicircles are closed forming a ring or shaft pillow on the structural element and they are fixed in position by means of attachment complementary elements disposed on both straight sides of the slit, producing the final disc shaped form to the device. The device of the invention has as a important feature that when it is closed, at the central axis, cylinder or shaft pillow, it does not fasten the steel, but it can rotate around the structural element as an axis; this freedom to rotate permits to the device to displace along the walls of any type of direct perforations in the soil, some of them without even walls or surfaces, so when the pile or wall is being introduced in the perforation or form, it maintains the metallic structure centered within the perforation, correctly locating the structure and assuring a minimal required concrete coating.
Regarding the problems found in this technical field, it is necessary to achieve a development with the following objectives:
It is an object of this invention to provide a device for spacing of a elongated element such as a reinforcement bar or structural element, from a reference surface such as the surface of a perforation or that of the form, or that of the adjacent wall designated to retain concrete; said device being made in one-piece, preferably configured with disc or ring shape, wherein the structural element is located inside a elongated ring or interior shaft pillow at the center of the device, and the distance to the reference surface is determined by the radial distance from the center towards the external surface of an external disc or ring.
It is another object of this invention that the spacer device contains a series of elements to coupling of the two sections that conform it, that provide high stability to the device once it is closed, avoiding deformation and sliding of the coupling sections, assuring uniformity in the longitude of the distance between the structural element and the surface of reference when the device is in use.
It is yet another object of this invention that the spacer device is easy to integrate to a reinforcement structure, when said device is incorporated on the structural element, passing it through a radial opening to the device and closing the device around the structural element; as well as to center or locate the whole structure when it is installed or introduced in the perforation to attain predetermined concrete coatings on said structural element.
It is a additional objective of this invention that the spacer device has a plurality of holes between an interior support ring for the structural element and an exterior ring, permitting the pass of concrete and aggregates through said holes.
It is another further object of this invention to provide a spacer device for structural element with respect to a reference surface, with an incremented resistance with respect to other devices on the art, because the gradual increment of width of the device from the external ring towards the internal ring, where it reaches the maximum width.
Other objects and advantages will be evident for a person skilled in the art, in view of the description and illustrative drawings following.
In order to have a better comprehension of the description of this invention, it must be read jointly with the figures annexed, which illustrates a preferred embodiment on the invention and where similar elements maintain the same numerical reference in all of them.
Following is a more detailed description of the invention, taking as reference the annexed figures which pretend to be illustrative of the features of the invention, and which must no to be considered limitative of the different modifications that can be obvious to a person skilled in the art, in view of this description.
Referring the
The set of external ring (110), internal ring (120) and the plurality of union elements, determine a set of holes (160) whose geometric configuration is determined basically by the walls of the union elements (180), the external face of the internal ring (120) and the internal face of the external ring (110), but it can be altered adding a reinforcement surface (190), plain and transversal to the semicircles.
The set (100) is divided into two sections essentially semicircular by a diametrical sectional line (130) dividing the internal ring (120) totally, the external ring (110) exclusively in one end of the diameter and the reinforcement surface (190) on said diameter, maintaining both semicircular sections joined together by an area of uncut material in the external ring (110), a flexible zone (170) that functions as a hinge to permit the opening and closing of said semicircular sections, as shown in
It is observed from the
Device (100) is then designed to an elongated structural element such as a metallic rod or similar reinforcement element, preferably with but not limited to circular cross-section, can pass through the entrance (130) when the device is in open or not-use position, up to the hollow space defined by the internal ring (120); once the elongated element is in its site, the device is closed by blending the flexible zone (170) as for the opposite ends of the entrance (130) are proximal.
Once the device is in its site, it is evident that the structural element occupy just the center of that, and said structural element will be always a distance at least equal to the longitude between its external surface and that of the external ring (110), with respect to any surface of reference in contact with said external face of the external ring (110). Because it is not necessary that the elongated element has a diametrical measure such that fits in the internal ring (120), the device maintains a rotate relation around its own axis, that coincide with the longitudinal axis of the elongated element inside; this feature is very useful even when, i. e. a metallic structure made by a plurality of structural elements disposed like a mesh must slide in a perforation such as a well drilled directly in the soil, wherein a plurality of devices as that of the invention, are distributed in the rebar cage or reinforcement cage or metal reinforcement structure in such a way that they function as casters to facilitate the displacement of the set, and once this is in its final position, guarantee that the structural elements associated are at a predefined distance from the walls of said well.
To assure that the device is maintained in its position with respect to the elongated element or rod located in its center, the device has a plurality of coupling and fastening means, said coupling means being constituted by a first hook engage able to a second hook (receptor) located preferably in the following way:
In a second embodiment, shown in
The set of external ring (210), internal ring (220) and the plurality of union elements, determine a set of holes (260), whose final geometrical configuration is basically determined by the walls of the union elements (280), the external face of the internal ring (220) and the internal face of the external ring (210), but it can be altered by adding a reinforcement surface (290), as described before in relation to the first embodiment. In the illustrated example said holes (260) are preferably circular, except those respective to the opening or entrance (230). In the illustrated embodiment, a parallel rib is added to the section (290) or, in the same direction that semicircles, obtaining higher rigidity for superior diameter models.
The external ring has a flexible zone (270) too, permitting a hinged movement for both semicircular sections, which when the device is in use position, close around the elongated element to the device operates as spacer.
It is appreciated in
Similarly to the first illustrated embodiment, the device of the second embodiment incorporates a plurality of coupling elements (250), (251), cooperative one to another and symmetrically disposed in the ends of the semicircles of the internal ring (220), diametrically as well as with respect to medium plane passing through the device. Coupling elements (240), (241) are present too in the opposite ends of the entrance (230). It must be noted that the symmetry with respect to the medium plane of the device is better shown in
In
Finally, in
Even that the qualities and advantages of this invention have been described on the basis of the illustrations of three preferred embodiments, it should be understood that those modifications a person skilled in the art could realize in the illustrated embodiments, will be within the scope of the invention that must be understood in view of the following claims.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/MX2005/000031 | 4/26/2005 | WO | 00 | 10/15/2007 |
