US2984947A

US2984947A - Spacers for steel inserts in reinforced concrete

Info

Publication number: US2984947A
Application number: US592428A
Authority: US
Inventors: Spatz Fritz; Spatz Werner
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-09-14
Filing date: 1956-06-19
Publication date: 1961-05-23
Anticipated expiration: 1978-05-23

Description

May 23, 1961 F. SPATZ ET AL 2,

SPACERS FOR STEEL INSERTS IN REINFORCED CONCRETE Filed June 19, 1956 INVENTOPJ United States Patent SPACERS FOR STEEL INSERTS IN REINFORCED CONCRETE Fritz Spatz and Werner Spatz, both of 14 Mulmkestrasse, Schwerte, Germany Filed June 19, 1956, Ser. No. 592,428

Claims priority, application Germany Sept. 14, 1955 5 Claims. (Cl. 50-507) This invention relates to a spacer for steel inserts in reinforced concrete serving tornaintain the required distances from the outside, and to a method for its production.

It is an object of the invention to provide a cheap spacer which is easy to handle and permits subsequent lifting or displacement of the steel inserts without being dislocated or tilting over.

Another object of the invention is to provide a spacer with a substantially punctiform support.

With these objects in view, the spacer according to the present invention consists of a perforated and preferably slotted disc which is provided with waves or corrugations. This disc-shaped spacer can be put on the structural steel netting or on single rods already on the fitting yard and ensures a tight clamping fit which permits also its attachment on vertical inserts.

The corrugations provided on the discs have the advantage that the disc is made very resisting thereby. First of all, however, they ensure a satisfactory, tight seat of the disc on the steel insert, so that it is held thereon in a position at right angles to the rod. Owing to the spring action of the spacer it is possible to fit the disc on round bracing and reinforcing irons of various dimensions, e.g. of 6-8 mms. diameter. By using a material of high elasticity, moreover, it is ensured that the spacer reassumes its original position at right angles to the round iron if it should be depressed by inadvertence.

The spacers according to the invention are produced either from a metal sheet and simultaneously provided with the corrugations, or from a strip corresponding to the width of the ring, bent into a ring and corrugated simultaneously or prior thereto, e.g. by means of corre sponding profiled rollers or the like.

Of late double-rod armourings have been increasingly adopted. In this type of armouring the interconnected rods are disposed parallel to each other and are arranged in known manner. In order to adapt the disc to such a double-rod armouring, according to the present invention it takes the form of a perforated and corrugated disc having a sector-shaped cut-out. In this way it is possible to fit the spacer on one of the discs while the second rod comes to lie in the sector-shaped cutout. The next spacer can be fitted on the second rod, being turned through 180 about the axis of its hole, while the first rod in this case comes to lie in the circular sector-shaped cutout.

Owing to the sector-shaped formation of the cutout it is' ensured that the armouring rod fitted with the spacer is seized by the inner circumference of the ring with an angle of grip ensuring a suflicient clamping fit of the spacer on the rod. Thus the rod is prevented from slipping out .of the central hole or of the sector-shaped cutout of the disc and hence the spacer is secured against being lifted off.

Each edge of the circular sector-shaped sector is preferably arranged on the crest of a wave, whereby the ice cutout can be provided in the disc in a simple manner.

In the accompanying drawings two preferred embodiments of the invention are shown by way of illustration and not by way of limitation.

Fig. 1 is a plan view of a ring embodying the invention,

Fig. 2 is a cross section on line 11-11 of Fig. 1,

Fig. 3 is a plan view showing a modification thereof,

Fig. 4 is a side view as per arrow IV in Fig. 3, omitting the steel rods, and

Fig. 5 is a plan view showing a spacer in the course of production.

Similar reference numerals denote similar parts.

Referring to the drawing in greater detail, it will be seen that the spacer consists of a disc 1 of a material of high elasticity, preferably of sheet steel which can be hardened. In the center thereof there is a hole 3 whose diameter corresponds to the outer diameter of the round steel serving for the reinforcing. As already mentioned, the hole may be of such a size that the disc owing to its elasticity can be engaged on rods of different diameters.

Furthermore, the disc is provided with radial corrugations 4 flattening towards its outer edge. Thus the highest waves are around the hole 3, so that a very good seat of the disc on the round steel is ensured. In order to facilitate the operation of placing the disc on the armour-lug rod, it is preferably split or provided with a radial slot 2, Fig. 1.

In the embodiment as per Figs. 3 and 4, which is intended for double-rod armourings, the spacer consists of a disc 1 having a central perforation and radially directed corrugations 4 flattening in an outward direction and formed with a circular sector-shaped cutout defined by edges 7 and 8 forming an angle of with each other. One of the two parallelly arranged armouring rods 9 is received in the central hole 3 of the disc while the second rod 10 is accommodated in the sector-shaped cutout between the edges 7 and 8 each of which is preferably arranged on the crest of a wave or corrugation 4. The walls of the form from which the bars 9 and -10 are to be spaced are indicated at 1'1 and 12.

A preferred method of producing the spacers is shown in Fig. 5. A straight strip of steel, preferably of a width of 10 mms., and a thickness of, say, 0.3 mm., is first corrugated, for instance, by passing the strip between two intermeshing toothed wheels spaced from each other by a clearance which corresponds at least to the thickness of the steel strip, then bent around a mandrel so as to form an annular disc, whereby the corrugations will be flattened in the outer part of the disc and increased in depth in the inner part thereof, and then cut 01f at 6. By way of alternative, the spacers may be punched and drawn out of sheet steel.

The depth of the corrugations preferably should be at least 6 ms, and advantageously 7 or 8 of such waves will be provided.

While the invention has been described in detail with respect to certain now preferred examples and embodiments of the invention it will be understood by those skilled in the art after understanding the invention that various changes and modifications may be made without departing from the spirit and scope of the invention and it is intended, therefore, to cover all such changes and modifications in the appended claims.

More particularly, our novel retainer, although specifically adapted as a spacer and locater for reinforced concrete, having the advantage of being fixedly seated on a steel rod over which it is slipped, may also be used for other purposes where such spacing and/or locating and such a fixed seat may be required, and it may be made of an elastic material other than steel, so as to suit the particular purpose or manner for which it is to be used.

I claim:

1. A spacer for accurately spacing reinforcement rods from form members in concrete structures, consisting of an arcuate member of substantially annular shape forming a central opening through which a reinforcement rod is'adapted to pass in holding engagement with said spacer, said arcuat'e member being corrugated so at to resiliently adapt itself to rods of different diameter and having alternating radially extending ridges and hollows arcuate in cross-section and forming along the circumference of said central opening axially extending edges adapted to engage said rod in axial direction there'- of so as to form an axially extending support for said spacer preventing tilting thereof relatively to said rod.

2. A spacer for accurately spacing reinforcement rods from form members in concrete structures, consisting of an arcuate member of substantially annular shape forming a central opening through which a reinforcement rod is adapted to pass in holding engagement with said spacer, said arcuate member being corrugated so as to resiliently adapt itself to rods of different diameter and having alternating radially extending ridges and hollows arcuate in cross-section and increasing in depth from the periphery towards said central opening and forming along the circumference of said central opening axially extending edges adapted to engage said rod in axial direction thereof so as to form an axially extending support for said spacer preventing tilting thereof relatively to said rod.

3. A spacer for accurately spacing reinforcement rods from form members in concrete structures, consisting of an arcnate member of substantially annular shape forming a central opening through which a reinforcement rod is adapted to pass in holding engagement with said spacer, said arcuate member being corrugated so as to resiliently adapt itself to rods of different diameter and having a1- ternating radially extending ridges and hollows arcuate in cross-section and increasing in depth from the periphery towards said central opening and forming along the circumference of said central opening axially extending edges adapted to engage said rod, in axial direction thereof so as to form an axially extending support for said spacer preventing tilting thereof relatively to said rod, said arcuate member being'split in radial direction forming radial edges spaced from each other a distance less than the diameter of said central opening.

4, A spacer for accurately spacing reinfo'rcementrods from form members'in concrete structures, consisting of an arcuate member of substantially annular shape forming a central opening through which a reinforcement rod is adapted to pass in holding engagement with said spacer, said arcuate member being corrugated so as to resiliently adapt itself to rods of different diameter and having alternating radially extending ridges and hollows arcuate in cross-section and increasing in depth from the periphery towards said central opening and forming along the circumference of said central opening axially extending edges adapted to engage said rod in axial direction thereof so as to form an axially extending supportfor said spacer preventing tilting thereof relatively to said rod, said arcuate member being split by a sector-shaped cutout forming substantially radial edges including an angle of up to 5. A spacer for accurately spacing reinforcement rods from form members in concrete structures, consisting of an arcuate member of substantially annular shape forming a central opening through which a reinforcement rod is adapted to pass in holding engagement with said spacer, said arcuate member being corrugated soas to resiliently adapt itself to rods of diiferent diameter and having alternating radially extending ridges and hollows arcuate in cross-section and increasing in depth from the periphery towards said central opening and forming along the circumference of said central opening axially extend ing edges adapted to engage said rod in axial direction thereof so as to form an axially extending support for said spacer preventing tilting thereof relatively to said rod, said arcuate member being split by a sector-shaped cutout forming substantially radial edges including an angle of up to 90, each of said radial edges extending along the crest line of one of said ridges.

References Cited in the file of this patent UNITED STATES PATENTS 307,777 Leggo Nov. 11, 1884 1,213,564 Williams Jan. 23, 1917 1,493,089 Walker May 6, 1924 2,527,985 Burroway Oct. 31, 1950 2,577,009 Frantz Dec. 4, 1951 FOREIGN PATENTS 428,950 France 1911 77,460 Austria ....4 1919 462,777 Great Britain 1937 575,653 Great Britain 1946 805,712 Germany 1951 814,218 Germany '1951