Me146 Chap13

Front 1

Used as cushions to absorb shock, as in machine supports, an automobile frames, and in airplane landing gear; as a source of power since they store up energy that is later delivered as driving power, as in clocks, trigger mechanism, etc.

Maintain contact between machine members by exerting a direct force, as in clutches, brakes, valve springs, and cam followers.

Are also used as loadeasuring devices, as in spring balances, power dynomometer, and in instruments such as gages, meters, and engine indicators.

Back 1

Spring

Front 2

Consist of a wire or rod wound into a helix and is primarily intended for axial direct compression or tension loads.

Back 2

The coil or helical spring

Front 3

Considers these stresses indicates that the stress at the inner surface of the coiled wire may reach values 60 percent higher. When the spring index is low.

Back 3

By A.M. Whal*

Front 4

The ratio of the mean coil diameter to the wire diameter.

Back 4

Spring index

Front 5

Made of square or rectangular wire are frequently used, since a stronger spring can be built into the same space required for a spring of round wire

Back 5

Coil springs

Front 6

The stress in a _______________, based on saint venant's torsion theory for noncircular bars.

Back 6

Square-wire spring

Front 7

_____________, with b/t between 1 and 2.5, indices greater than 3, and with the long dimension parallel to the spring axis.

Back 7

Rectangular wires

Front 8

The spring index for coil springs of noncircular wire may be closely approximated by using the ratio of the mean coil diameter to the dimension of the of the wire perpendicular to the axis

Back 8

The spring index for coil springs of noncircular wire may be closely approximated by using the ratio of the mean coil diameter to the dimension of the of the wire perpendicular to the axis

Front 9

Found from the angular twist of the coiled wire.

Back 9

Axial deflection of the spring

Front 10

Certain installations require a spring with increasing stiffness as the load increases, i.e., a decreasing rate of decflection per unit load.

Back 10

Certain installations require a spring with increasing stiffness as the load increases, i.e., a decreasing rate of decflection per unit load.

Front 11

Will generally be in coil of largest diameter but since the spring index decreases at the small end, the stress should be checked in the coil of least diameter.

Back 11

Maximum stress

Front 12

For general industrial uses the spring index should be ___to___; for valve and clutch spring ___ is common; and ___ is a minimum value to be usesd only in extreme cases.

Back 12

8to10

5

3

Front 13

The solid lenght plus the clearance plus the maximum deflection.

Back 13

Free length

Front 14

Depends upon the number of effective coils and the type of end provided.

Back 14

Solid length

Front 15

Different types of end

Back 15

Plain end

Ground

Squared end

Squared and ground end

Front 16

The _____________ of coils n may be less than the actual number of spring.

Back 16

Effective number

Front 17

That is to long compared to its mean diameter may buckle at comparatively low axial loads since such a spring is a very flexible column.

Back 17

Helical compression spring.

Front 18

That will cause buckling .

Back 18

Critical axial load

Front 19

May be considered as one supported on pivots at both ends.

Back 19

Hinged-end spring

Front 20

As one in which a squared and ground end spring is compressed between two rigid and parallel flat plates.

Back 20

Built-in end

Front 21

are usually wound with the coils closed and under an initial tension ; it is necessary to apply from 20 to 30 percent of the maximum load before the coil begin to seperate.

Back 21

Tension spring

Front 22

The design stress for tension springs should not exceed ________ percent of that used with compression springs.

Back 22

70 percent

Front 23

Extension spring ends

Back 23

Plain end and screw eye

Straight end

Conical end and bolt

Loop on side

High loop

High hook

Loop on center

Extendend eye on center

Front 24

Is used for diameter of ferrous wire.

Back 24

Washburn and Meon (W&M) gauge

Front 25

Is used for nonferrous wire.

Back 25

American wire gauge (AWG) or Brown and Sharpe (B&S) gauge

Front 26

The majority of coil springs are made of oil-tempered carbon-steel wire containing ____ to____ percent carbon and ____ to ____ percent manganese.

Back 26

0.6 to 0.7 percent

0.6 to 1 percent

Front 27

Used for high-grade springs using wire less than 1/8 in in diaMeter.

Back 27

Music wire

Front 28

Annealed wire containing _____ to _____ percent carbon and ____to_____ percent manganese is used in larger sizes, which are coiled hot and are hardened and drawn after after coiling.

Back 28

0.85 to 0.95 percent

0.30 to 0.40 percent

Front 29

Metal that can be hard drawn are Used in special cases to increase fatique resistance, corrosion resistance, and temperature resistance.

Back 29

Nickel steel

Chromium steel

Stainless steel

Brass

Phosphor bronze

Monel metal

Front 30

Increase the endurance range of steel spring

Recommended for ferous helical springs.

Back 30

Shot peening

Front 31

Increases from 75 to 85 percent of ultimate strenght as the diameter decreases.

Back 31

Yield stress

Front 32

Yeild stress in tortion is approximately 45 percent of the ultimate strength in tension for _________ and 35 percent for _________.

Back 32

Oil tempered wire

Hard drawn wire

Front 33

Should not exceed 80 percent of yield stress in torsion.

Back 33

Safe working stresses.

Front 34

The actual frequency of the spring is from ____ to____ percent.

Back 34

10 to 15 percent

Front 35

Used as cushions on flexible drives transmitting rotary motion or torque and source of power for driving such mechanisms as clocks

Back 35

Torsion spring.

Front 36

Two types of torsion spring

Back 36

Helical torsion spring

Spiral torsion spring

Front 37

The wire may be coated with _____ or _____.

Back 37

Cooper or tin

Front 38

Springs may be electroplated with ......

Back 38

Cadmium

Chromium

Nickel

Brass

Cooper

Front 39

The stress in the full length leaves was found to be ______.

Back 39

50 percent

Front 40

In general the ratio do/di should be between

Back 40

1.5 and 5...

Front 41

Types of spring leaf ends

Back 41

Square ends

V end

Rounded end

Round end

Oval end

Tapered

Front 42

The wire is subjected to flexural stresses.

Back 42

Helical torsion spring.

Front 43

A single thin plate.

Back 43

Leaf springs

Front 44

Typical semielliptic leaf spring

Back 44

Camber

Eye

Rebound clip

Center clip

U bolts