US1674120A - Steel or iron pillar particularly adapted for mounting electric wires - Google Patents

Description

June 19, 192& 1,674,120

I. NOZAWA STEEL 0R IRON PILLAR PARTICULARLY ADAI TED FOR MOUNTING ELECTRIC WIRES Filed May 11, 1925 g a i ZJLJLJLJL 3 wwmtoz attozvmq 5 Patented June 19 1928 UNITED STATES PATENT OFFIE.

ICHIRO' no'zAwA, or TOKYO, JAPAN.

STEEL OB IRON PILLAR PARTICULARLY ADAPTED FOR MOUNTING ELECTRIC WIRES.

Application med Mayll, 1923. Serial No. 638,871;

The invention relates to steel or iron pillars of a hexagonal shape in cross section at the point of horizontal bracing, particularly adapted for mounting electric wires. Heretofore a pair or pairs of 90 degree angle iron or steel have been used with diagonal bracings' on each outer side but there is a drawback that resistance to bending and twisting is not so great as could be expected. Besides the manipulation in using 90 degree angle iron or steel is sometimes diflicult due to the particular angularit and in case where such iron or steel longitudinally bent at right angle, available in the market, isemployed to form a column, it is liable to fracture at the angular point." It has been heretofore unsuccessful to use other angle irons orsteels than the ones of 90 degree but according to my invention, angle irons or steels of 120 degree angularity or' from about 110 degree to 140 degree, drawn or bent, are utilized to form a pillar to a greater advantage than in the case of 90 degree angle iron or steel.

The foregoing and other features are hereinafter referred to and the preferred embodiment of the invention will now be described with reference to the accompanying drawings in which,

Fig. 1 is a cross section of the pillar; Fig. 2, a fragmental elevation; Fig. 3, a front elevation of whole pillar completely equipped; Figs. 4 and 5 are diagrammatic views of cross sections of arrangements of columns illustrated to explain the comparative advantages of the present construction over other constructions.

As shown in Figures 1 and 2, the sides A and A of one column are made equal to each other and the sides B and B of another column are likewise equal to each other,

with the angle subtended by the sides A and A and the angle by the sides B and B being each equal to the interior angle of a regular hexagon, these four sides constituting four sides of a hexagon.

In this way the material to form each column is drawn or longitudinally bent, as the case may be and AA and BB represent columns both of which constitute a pillar body as claimed in this application. Both columns are jointed with horizontal bracing 0, connected to the members A and B by welding, riveting, or other usual means, and arranged in spaced relation to form a rigid pillar which is a hexagonal which free end a force P equal to the load resulting from the weight of carried electric wires is acting.

According to Eulers formula,

.' P 41r EI T where P=collapsing load.

E Youngs modulus. l Moment of inertia of a cross section. L=Length of the pillar.

It will be seen that where E and L are constant, as in the case of pillars or the like of equal lengths and same quality of material, the collapsing load varies in direct proportion to the value of moment of inertia.

Further suppose that by some accident wires on one side of the pillar are broken or that wind pressure on the wires is assumed as the only load to be taken into consideration, the pillar may be regarded as a beam, one end of which is supported and other end free on which beam an isolated load or uniformly distributed load is act- H10.

in this case,

where M=Resisting moment.

p =Radius of curvature of neutral axis of the beam.

It follows therefore that if E and p are constant, in other words, if pillars are constructed of same material, resisting moment varies in direct proportion to moment of inertia of the cross section. The above constitutes the basis of the theoretical treatment given below in order to exemplify the novelty and utility of the present invention.

In Figure 4 there is shown an arrangement in which the column is formed of members having equal sides a and a drawn or bent at a right angle. In this figure XX represents a horizontal neutral .axis and YY a vertical neutral axis.

Now suppose as shown in Figures 4 and -5, the sides (10 should be made equal toeach other and of the same cross sectional areas. The total sum of the areas of the particles is the same in Figures 4 and 5 but as the value of r in Figure 4 is considerably smaller than r in Figure 5, the total sum of 7"(70. that is.

is considerably less in Figure 4. This means that the moment of inertia in Figure 5 is far greater than in Figure -l-.

It is also noted that while the construction in *Figure 4 is (lllll'flllt in manufacture due tothe particular angularity ot' the sides, that of Figure 5 is more adapted to ma.- nipulation on 'accou-ntoi that the sides are outwardlv flared.

I wish now to point out various advantages gained by mv invention.

(1) The present pillar which is mostly intended for mounting electric wires gives more resistance to bending and twisting strains.

(2) Asthe-angles between the sides of the columns are each about 120 degree. there is a. decided advantage in readily mounting necessary arms and brackets for electric wires.

(3) As the angles between the sides of the columns are each obtuse angle, there is no tendency of the material being fractured .in bending treatment.

(at) The pillar constructed in accordance with this invention gives a beautiful appearance due to harmony of the constituent parts.

(5;) Although a single column havin an obtuse angularity between two longitu inal parts .is not so strong as one of 90 .(legrce,

the. assemblage of a pair of same to form a spaced pair oi two contiguoussides of a hexagon .in cross section atl'ords greater strength than the similar arrangement of columns of '90 degree angularithy.

W hat I claim is:

A column for supporting electric wires, con'iprising, two upright steel angle members, each member having two plane sides meeting at. an angle ofap proXinmtely 120,

the steel members being placed facing each other with their apexes outward, and spaced so as to form in cross section, four sides of .a regular hexagon, and braces rigidly connecting the members together.

Signed .at American Embassy, Tokyo this 17th day of April A. 11,1923.

ICHLRO NOZAVVA.

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