US 2462399 A
Description (OCR text may contain errors)
' Feb! `22,4 1949. fw n. D. HINQHMAN 2,462,399
CONDU'IT SPACER Filed Sept. 16, 1944 n 1N VEN TOR.
`Patentecl Feb. 22, 1949 UNITED-1 STATES PATENT OFFICE GONDUIT SPACER William.^H. D. Hinchman, Detroit, Mich.
Application Septemberli, 1944, Serial No. 554,513n
1 Claim. l.
` This invention relates to Y af conduit spacer.Y
Conduitspacers are commonly-used inl-spacing underground conduits` for power conducting lines. Concrete4 is poured-around Vthe conduits and spacers. This mass of concrete about the conduits is often required to carry considerable loads comprising not only the weight of the ground covering the conduits, but where the conduits are laid under streets this concrete must also bear the Weight of traffic upon the street. Since these conduit spacers are arranged in tiers one upon the other, it is essential that the concrete on opposite sides of the spacer should be joined into a homogeneous whole otherwise a joint will result which will cause, under certain loads, a fault or rupture in the concrete body thereby either closing off the conduits or partially closing them in the area of the fault.
It is an object of this invention to produce a conduit spacer which is light and yet at the same time strong so that it will bear stresses from any direction and which will permit the concrete on opposite sides of the spacer to unite and form a homogeneous or jointless whole.
Fig. 1 is an elevation of my conduit spacer.
Figs. 2 and 3 are sections along the lines 2--2 and 3--3 of Fig. 1 and Fig. 4 is a section along the line 4 4 of Fig. 5.
Fig. 5 is a sectional View through a series of conduits showing the spacers in use.
The spacer can be made from any suitable material such as thermoplastic and thermosetting materials or pressed ber board.
One of the important features of the invention is to combine great strength with lightness. To this end the spacer, which is generally designated l, is made in the form of an I section cornprising a frame 2 and reinforcing webs 3.
The frame 2 constitutes a closed frame havin?- similarly formed top and bottom sides and 5 respectively and ends 6 and l. The top and bottom sides are formed with opposed arcuate portions 8 and 9 which serve as seats for the conduits Iii. Reinforcing ribs II connect arcuate seats 8 and 9 at their mid-portion. The spacer is provided with openings I2 through which the concrete I3 flows.
In use the conduit spacers are placed in tiers with intervening rows of conduits li) and concrete I3 is poured over the conduits and spacers. It will be noted that the concrete flows through openings I2 so that the bed of concrete is a homogeneous whole and thereby a joint or fault in the plane of the tier of spacers is eliminated. Such a fault would permit slippage of the concrete oneither side of the tier of conduit spacers and thereby either destroy or restrict thecon-A duits so that they would not be useful.
With the construction of my spacer, as abovey described, it will be noted that regardless of the direction from which the stress o1' strain is placed upon my spacer there will be ample strength in the part of the spacer upon which the stress falls to resist the same and support the load. It will be noted that if the strain or load is in a vertical plane, the reinforcing webs 3 which extend completely around the inner circumference of the spacer will take this load or strain and if the load is in a horizontal plane, as the spacer is positioned in Fig. 5, which is a vertical section, the frame itself will take this strain or load.
The concrete also fills the pockets i5 which are formed by the reinforcing Webs 3 and the frameportion surrounding each of the openings I2 including the ribs I! which form the ends of the pocket.
Openings I2 permit the use of reinforcing steel rods 20 running parallel to conduit Iii and passing through openings I2. The weight of the conduits rests on the portions of the spacers intermediate the opposed arcuate seats 9, but this area is reinforced by ribs II as well as Webs 3 which form a cross in horizontal section, Fig. 4.
The peripheral flange or frame 2 of the spacer resists strains which tend to bend the spacer in a horizontal plane, as viewed in Fig. 5, and the web 3 resists strains which tend to bend the spacer in a vertical plane. The concrete which flows into pockets I5 and through openings I2 ties the tiers ofspacers together' to prevent shearing of the conduits. It is also evident from the above that when the spacer is made from light materials, like theromplastic material or pressed fiber board, that the provision of the peripheral ange or frame 2, plus the vertical webs 3, Will give the spacer sufficient stiffness and strength to permit handling without bending in any direction and to serve as supports for the conduits before and during the pouringof, and embedding the conduits in, concrete.
The spacer can be made from plastics such as the vinyl resins, methyl-methacrylate, ethylcellulose, polystyrene, urea formaldehyde and phenyl formaldehyde reaction products.
The fact that the above described spacer is considerably lighter than the ordinary concrete spacer now in use makes .my spacer not only easier to handle but safer. It is a common occurrence for these spacers to be thrown to a man in a ten foot deep trench who is installing the conduits. Not infrequently the throw will be inaccurate and the spacer will hit the receiver on the head. Since my spacer is made from a light plastic or ber board material, no harm will result in case the receiver is hit on the head.
My spacer is formed from electrical insulating materials, such as plastics and cellulose fibers, and due to its strength requires no metal reinforcement. VThe presently used concrete spacer requires a metal reinforcement and, since the spacer extends crosswise of the cables or wires in the conduits, these metal reinforcements are heated inductively between the phases of the current. This inductive heating of the metal reinforcements results in a wastage of electric power. This defect is eliminated by my nonmetal or non-conducting spacer.
In a spacer for conduits comprising a closed frame member having top and bottom walls with opposed arcuate portions adapted to serve as seats for conduits, reinforcing webs joining the top and bottom walls in the area adjacent 'the mid-section of the opposed arcuate portions, said webs extending in a plane perpendicular to the plane of the top and bottom Walls and extending throughout the inner periphery of said frame, the Webs separating in the area of the top and bottom Walls adjacent the ends of the arcuate seats whereby openings are provided through the spacer in the area between the mid-sections of the arcuate portions.
' WILLIAM H. D. 'HINCHMAN- REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 501,914 Bruner July 25, 1893 845,789 Hussey s Mar. 5, 1907 1,704,097 Muhleisen Mar. 5, 1929 1,821,234 Parker Sept. 1, 1931 1,834,404 Koch Dec. l, 1931 2,181,664 Melzer Nov. 28, 1939 2,354,919 LockwOOd Aug. 1, 1944