US1643073A

US1643073A - Spring

Info

Publication number: US1643073A
Application number: US84222A
Authority: US
Inventors: Elmyr A Laughlin
Original assignee: Individual
Current assignee: Individual
Priority date: 1926-01-27
Filing date: 1926-01-27
Publication date: 1927-09-20
Anticipated expiration: 1944-09-20

Description

Patented sept. 20, 1927.

sparire.

This invent-ibn relates ,t new and: useful improvements, in springs.; and. Particularly to coil springs usedinconnection with railway. car trucks, alth'ough such Springs are One object ofthe invention is to, provide a coil spring of a giyen`length whichwill the length Vof travel, rthan springs hereto- Another object is to provide a springrof this character which is formed vby coiling the stock on a mandrel, and wherein the stock is formed with a longitudinal flat portion on the side nextk the mandrel, which permitsI the metal to expand into the body of the stock without theV usual ribs, which would prevent the full compression of the spring, and thereby shorten its length of trav-el within a given space.

Another object is to provide a coil spring` of this character wherein each convolution, in cross section, presents a greater transverse dimension at the side next the mandrel, with the result .that when the spring is in operation the torsional strain on each individual coil will have as its center the thicker side of the stock of the spring.

Other objects and advantages will be apparent from the following description when taken in connection with the accompanying drawing.

In the drawing:

Figure 1 is a longitudinal sectional view of a spring made in accordance with the present invention. t

Figure 2 is a transverse sectional view through the stock from which the spring is formed, before the stock has been wound on a mandrel.

Figure 3 is a similar sectional view after having been ywound on the mandrel, and showing the position of the center of the torsional strain incident to the normal operation of the spring, when under compression strain.

Referring particularly to the accompanying drawing, there is shown a coil spring each convolution of which is tapered in cross section, with the narrower portion lying at the outside of the spring, and the wider portion at the center of the spring. The narrow portion is represented by the numeral 10, and the wider portion by the numeral 11. It will be further noted that the upper and lower faces of the convolutions are flat, thatltheirends are connected4 b y the curved portions gl 2 and 13, respectively. It will be further noted that -the curved, face 13 is formed with ',liat spot or stock from` which the spring is formed. i

I'n'xthe .use 'ofa coilspring 'in which the convolutions are7 circular. in` cross section, the

f tlme pf. @tht/...Springtoward fulll Compression, is limited by the bulging curved adj acent faces of the said convolutions. nThis is inconvenient when the spring must have a definite space in which to travel, and support or resist a great load. Attempts have heen made to remedy this feature by flat-tening the contacting faces of the convolutions. lVheii, however, the stock is coiled on a mandrel, the portion of the stock next to the mandrel, will naturally spread, thus mak-ing the inner port-ions of the coils wider by the presence of rib and thereby decreasing the length of travel of the spring. This is especially noticeable where the ends of the cross sectional areas of the convolutions are flat, as well as those which are arcuate. To overcome this defect in the coiling of t-he spring, and to provide a spring which will have great resistance to a load, and yet have the maximum of travel, within a given space,

I form a flat face throughout thelength of thestock of the spring, before coiling the sam-e on a mandrel. This fla-t face, which is shown at 14, is placed next to the mandrel. The curved portion of the stock. in which this flatface is formed, is wider than the portion at the opposite side of the coil, so that when the stock is coiled around the mandrel, the expansion of the metal, due

` to the compression at the mandrel, will spread into the

corners

15 and 16, of the stock.

Vhen the spring is under compression strain, the individual coiivolutions rotatev about an axis located at 17, which is in the wider portion of the coil turn. Thus the narrower side of the coil turn rotates or rocks on the said torsional axis at 17.

While I, have illustrated the fiat faces of the convolutions as converging, with one of such faces at right angles to the longitudinal axis of the spring, and the other oblique thereto, it will be understood that both of the said faces may be oblique to the axis of the spring,l the principal result being in producing outwardly converging faces.

1. A coil spring each convolution of which has a cross sectional contour including opposite converging faces and opposite arcu` ate faces.

2. A coil spring each convolution of which has a cross sectional contour including opposite substantially flat faces and an arcuate face, said arcuate face havingan in tern'iediate flat portion.u

3. A coil spring each convolution ot which has a cross` sectional contour including opposite substantially flat faces and opposite arcuate faces, onc of the arcuate faces having an intermediate flat portion.

t. A coil spring each convolution of which has a cross sectional contour including opposite converging faces and opposite arcu ate faces, one of the arcuate faces having an intermediate flat portion.

5. A coil spring each convolution of which has a cross sectional contour including opposite substantially fiat converging faces and opposite arcuate faces.

In testimony whereof, I aix my signature.

ELMYR A. LAUGHLIN.