86174_12

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I L

L U

S

T

RAT E

D

S

O U

R C E

of ME

C

H A N I

C A L

C MP N E N

T

S

S E C T I O N

12

RETAINING

Comparisons of Retaining Rings Verses Typical Fasteners

12-2

12-4

12-6

12-8

Retaining Rings Aid Assembly, I

Retaining Rings Aid Assembly, II

Coupling Shafts with Retaining Rings

The Versatile Retaining Ring 12-12

The Multiple-Purpose Retaining Ring 12-16

More Work for Round Retaining Rings

12-18

12-20

12-22

12-24

Energy Absorber Squeezes Rings to Cushion Shocks

Defection of Perpendicularly Loaded Split Circular Rings

Improve Design with Retaining Rings

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12-2

Comparisons of Retaining Rings

Verses

Typical

Fasteners

A

variety

of

basic applications show how these rings simplify design and cut costs.

Howard Roberts

MACHINED SHOULDERS are replaced

with savings in material, tools and time.

Grooving for ring can be done during a

ut-off, or o ther m achining operation.

WHEN COLLAR AND SETSCREW

are sub-

stituted by ring, risk of screw vibrating loose

is

avoided. Also,

no

damage to shaft

by

screw

point occurs- frequent cause

of

trouble.

RINGS

THAT

CAN REPLACE

cotter pin

and washer are economical since only one

part

is

required and pin-spreading operation

is not needed thus cutting time and costs,

8/11/2019 86174_12


RETA IN COMPONENTSon diecastings with

a simple-to-use grip ring. Slipped over the

end of the shaft, the ring exerts a frictional

hold against axial displacement

of

the shaft.

r---i

Retaining Rings 12-3

7

SHOULDER AND NUT are replaced by two

retaining rings.

A

flat ring replaces th e shoul-

der, while a bowed ring holds the com ponent

on shaf t f or res i l ien t end-p lay take-u p ,

THREADED INTERNAL FASTENERS

are

costly because of expensive internal thread-

ing operation. Simplify by substituting a self-

locking retaining ring-see lower drawing.

COVER-PLATE ASSEMBLY

has been re-

designed (lower drawing) to avoid use of

screws and machined cover-plate. Much thin-

ner wall ca n be used-no drilling or tapping.

w

W

HEAT-FORMED STUD provides a shoulder

against retained parts but must be scrapped

if the parts must be disassembled for serv-

ice. Self-locking ring can be easily removed.

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12-4

Retaining Rings Aid Assembly,

I

By Functioning as both a shoulder and as a locking device these versatile fasteners

reduce machining and the number and complexity of parts in an assembly.

Robert0 Parmley

Slow-moving piston of hydraulic motor is assembled to the crank throw by

two

retainers. These are held in place by two retaining rings that

fit

into

grooves in the crankthrow

Internal self-locking ring supports a

locator. Elevation of the pin may be

altered in the entry direction only; the

pin won't push down into the frame

TWO ort ring

, ~ - P c housing

Two-piece interlocking retaining ring

serves to hold a two-piece assembly on

a rotating shaft, and is more simple

than a threaded cap, a couple of

capscrews or other means of assembly

Source: American Machinists, June3, 1968 by permissionof Publisher

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Free ring

Groove detai l

Roller

Roller axle

Heavy-duty

Two types of rin gs may be used on one assembly. Here permanent-shoulder r ings

provide a unifo rm axle step for each roller, without spotwelding or the like.

Heavy-duty rings keep the rollers in place

Reinforced circular

self- locking

r a p e r e d

-section

self- ocking


Reinforced

E - r ing

Bowed

locktnq-

prong ring

Snug assembly

of

side members to

a casting with cored hole is secured

with two rings: 1-spring-like ring has

high thrust capacity, eliminates springs,

bow washers, etc; 2-reinforced E-ring

acts as a retaining shoulder or head.

Each ring can be dismantled with a

screwdriver

~ ~ i l ~ ~ ~ ~ ~ ~ g

riangular retaining nu t eliminates the

need for tapping mounting holes and

using a large nu t and washer. Secure

mounting of small motors and devices

can be obtained in thi s manner

These three examples show self-locking retaining rings used as adjustable

,stops on suppor t members (pins made to commercial tolerances): A-external

riu g provides positive grip, and arched rim adds strength; B-ring is

adjustable i n both directions, but frict ional resistance is considerable,

and C-triangular ring with dished body and three prongs will resist extreme

thrust. Both A and

C

have one-direction adjustment only

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12-6

Retaining Rings

Aid

Assembly, II

Here are eight thought-provoking uses for retaining rings.

R o b e r t

0. Parrnley

Heavy duty ring

\733

Retaining ring

Axial pin for lever is secured with a heavy-

duty ring, making a neat, strong assembly

Free ring Ring af te r assembly

P i n t

Belt alignment is assured by using permanent

shoulder retain ing rings. The rings are crimped

into the sha ft grooves for a permanent, clean,

and inexpensive flange. A retainer ring of

thi s type has a high capacity for thrus t loads

Bdz

Detai l

of

groove

Adjustment:

u p only

Ho

anger

hook

is

held

at desired height by

a self-locking external ring. A multitude of

adjustments can be made without troub le

Retaining rng,

Bal l

Coi

Housing

Sleeve or

valve

ball

seat

A sleeve or ball

seat

valve is safely retained

by a ring that acts like a wedge in the outer

groove. Rigid end-play take -up is provided

Source: American Machinist, Feb. 22, 1971 by permission of publisher.

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\ .Housing

\

Ring

\ f

Vacuum

released

Interna l self-locking ring supports the plastic ball valve

when the vacuum is released, thus providing a support

during the off cycle. Air or liquid is released when ball

is at rest and exits through the areas between the gr ip

points of the ring, which i s adjustable at entry position

s+em-----.m

Weight

disc,

.Ring

-Rubber stopper

w i t h internal

threaded s l eeve

Drain hole

Triangular retainer nut positions and unifies components of

the tank drain assembly. The triangular nut eliminates the

need for a large standard nut and lockwasher or spring-

type component and simplifies the design

Tamper-proof lock for a shaft in a

housing provides location of the

shaft and a t the same time retains

the key. Heavy axial loading and

permanent retention of the key are

double values in thi s application

Ring hal f \

Observation

lid .

I*

ing half

Observation lid on tubing makes it

possible to inspect wiring at will.

The two-part balanced retainer ring

has identical semicircular halves,

which are held together by the

interlocking prongs at the free ends

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12-8

Coupling

Shafts with Retaining

Rings

These simple fasteners can provide an original way around certain design snags.

For example here are eight ways they’re used

to

solve shaft-coupling problems.

Robert 0. Parmley

S l e e v e

Pin,

Sleeve, and Ri ng 1 ,

Pre-assembly position

1

I

A

/ ’

This

inexpensive connection

i s

for light torques and moderate

loads where accurate positioning

i s

not required. A heavy-duty ring

i s used to resist high-impact and

thrust loads.

Sleeve

Key, and Ring

Retaining ring

S h a f i

Crimping the retaining ring into

the groove produces a permanent,

simple, and clean connection.

This

method i s used to avoid machining

shoulders in expensive materials,

and

to

permit use of smaller-diarn-

eter shafts. When the ring i s com-

pressed into a V-shaped groove on

the shaft, the notches permanently

deform into small triangles, caus-

ing a reduction of the inner and

Sie‘eve outer diameters of the ring. Thus,

the fastener tightly grips the

groove, and provides a

360-deg

shoulder around the shaft. Good

torsional strength and high thrust-

load capacity

i s

provided by this

connection.

I

Retaining ring

Crimped afier

assembly

Reprintedwith Permission rom Machine Design, Jan.

19,

1967. A Penton Publication

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Retaining Rings

Shaft h a l f

etaining r ing

A

balanced two-part ring provides an attractive appearance in addition to with-

The one-piece ring, b,

tanding high rotational speeds and heavy thrust loads,

a.

secures the shafts in

a

high-torque capacity design.

12-9

This

assembly for heavy-duty service requires minimum machining.

Ring thickness

should be substantial, and extra ring-section height i s desirable.

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12-10

self-locking ring

ha f t

VA ----_____I14

I I

r

For a connection tha t requires ax ia l shaft adjustment, the self-locking ring requires

An alternate solution, b, uses an inverted-lug ring seated in an internal

The ring i s uniformly

no groove, a.

groove.

concentric with housing and shaft.

Extra ring-section height provides a good shoulder.

Coupler and

Coup1;ng hal f

Retaining

r i ng

Ring groove I Couplings locked to shafts

with s ei screw and k e y s

Where attractive appearance i s desired in a dependable locking device, this

connector and ring can be used.

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/Tapered threadse t c i n i n g r in g eeve

/

S h a f t

-

f l a t washer for bet ter contad

A slotted sleeve with tapered threads connects shafts which cannot be machined.

Prongs on the retaining ring provide positive shaft gripping to stop collar movement.

The arched rim add s extra strength.

Seam

Coup l i ng

half

An alte rnat e solution for coupling unmachined shafts uses bossed coup ling halves

with locking retaining rings.

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12- 12

The Versatile Retaining Ring

A

design roundup of some unusual applications

of

retaining rings.

Robert

0

Parrnley

\

RETAINING RING

I

Fig 1

The assembly

of

a hubless gear and

threaded shaft may be accomplished by

using a triangular nut retaining component

which eliminates the need for a large stan-

dard nut and

lock

washer

or

other spring

type part. The dished body of the triangular

nut flattens under torque to lock the gear

to t h e shaft.

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E v c r y enginecr is famil iar wi th the

uye of ietai ning rings in produ ct as-

scmbly. Applications for this type of

fastening device range from minia-

ture clectronic asscmblics to heavy

cluty eq uipm ent.

In

spite

of

this wide-

spread use, many opportunities for

taking advantage of these versatile

fastening components oftcn arc ovcr-

looked. However, when

a

value en-

ginecring approach is talccn and thc

basic function of retaining rings as

easily assemblccl locating and locking

devices is lccpt clearly in mind it

will

be found tha t

these

simple fasteners

can provide

a

unique solution to dif-

f icult assembly problems.

This roundup of 8 unusual appli-

cations il lustrates how different types

of retaining rings

have

been used to

simplify assembly and reduce manu-

facturing costs . Thc captions under

thc drawings givc the details involved

in each case.

The author wishes to acknowledge

with appreciation the cooperation he

received froin the Tivarc Retaining

Ring5

Division of Waldes Kohinoor,

Inc. in developing these assembly

designs.

Fig 2 This heavy duty hubless gear and

shaft is designed for high torque and end

thrusts. The reta ining ring seated

in

a square

groove and the key In slot provide a tamper-

proof lock. This design is recommended for

permanent assemblies in which th e ri ng may

be subjected to heavy loads from either or

both axial directions An angled groove can

be provided which has one wall cut: at a

40

angle to the sh aft axis. This wil l p ermit

the ring to be removed without damage.

@

S H A F T

IN iAT

URE YIGH-STRENCTH

RETAINING RING

/

/

Fig 3 Two different types of retaining rings

are used in this application involving a leaf

sprin g and shackle assembly. A locking -pro ng

retaining ring is bowed for tension while the

prongs act as fastening elements to secure

the pivot bolt. A fiat or standard external

ring is used as a flange or bolt head.

LEAF

RING

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12-14

Fig 4 The self-locking retaining r ings used

in this application provide stops for a float.

The rings are adjustable on he guide rod and

yet the friction force produced by the heavy

spring pressure makes axial displacement

from the light weight hollow float impossible.

FREE

RING

I

Fig

5

Retaining rings provide a uniform ciT-

cular shoulder for small diameter parts such

as the pipe nipple shown

here. In thi s case

the retaining r ing shoulder

s

used as a

stop fo r the plastic tube. The wall thickness

of the n ipple should be at least three times

as thick as the depth of the groove. When

assembling the ring in the groove, the nipple

should be supported by inserting a mandrel

or rod.

SEC. A-A -

R ING

RING

AFTER

ASS'M.

I

\

PERMANENT-SHOULDER RETAIN ING RING

MOISTURE

JAR

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CONNECTING ROD

\

/

i

PISTON

PISTON AS5 M.

/

'CONNECTING. ROD

I

F R R;NG -

Retaining Rings

Fig 6 This internal retaining ring is a key part

in

the

assembly of a connecting rod and piston for a hy-

draulic motor. The ring's lu g holes make rapid assembly

and disassembly possible when the proper pliers are

used. The piston assembly in this case is slow moving

and is not subject to heavy cycle loading.

Fig 7 Internal self-locking rings can act as a su pport

carrier when the

I.D.

of a sleeve or housing cylinder

is too larg e to center and stabilize small rods or con-

duit. The rings are adjustable in the entry direction

only, however, and a sufficie nt nu mber should be used

to secure the rod.

l

I

I

ADJUSTMENT'

DIRECT I 0 N

CYCLINDER

12-15

A

INTERNAL

SELF-LOCKING

RETAINING RING

Fig

8

The heavy duty external reta ining rin g shown

here controls the elevation or position of a support

post in a holding clamp. This type of ring

is

ideal for

heavy duty applications where extreme loading condi-

tions are encountered. By adding washers under the

ring the elevation of th e support post can be adjusted

as required.

NL

ARG

EME

T

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12-16

The

Multiple-Purpose

Retaining Ring

A

roundup

of

ten unusual ways for putting retaining rings to work in assembly jobs.

Robert

0

Parmley

7

Standard e x t e r na I. y p e

ring

serves as adjustable stop or

shoulder for positioning sleeve

members on post or shaft.

T h e

post i tsel f is locked to t he base

by a retaining ring.

Adjustment

Platform

Radius Arm

Hub

Retaining

Ring

1

Special iugless

ring

of external

type is used

to

offset center.

l ine of shaft which i s station-

ary or roteting slowly in hub or

journal.

Shaft Centerline

4

Retaining Rine

-

F l a t Washer

Tape

Coil S

Movable Head

Sel f- lock ing e x t e r na l ring i 5

used with flat washer to pro.

vide adjustable shoulder for

control of spring action.

Supported Plate Load

\ L

etaining Ring

Retair

Heavy duty self-locking ring

acts as adjustable stop on pin

used as support me mber for

plate section.

Excerpted from Assembly Engineering, July, 1966 by permission of Publisher 0 1966. Hitchcock Publishing

Co.

All rights reserved

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Retaining Rings

12-17

Retaining Ring

Panel Section

Contact

h n t

Retaining R I ~ E

Bowed ring with locking prcngs

act: as fast ening element and

sprin g fcr clectrical pu;h but -

tcn.

Retaining Ring

5

Self-locking external rin g con.

trols position

of

eye rod

in

an

adjustab le ca b l e h an ge r ar.

rangement.

Retaining Ring

Clamp

t

S t a n d a r d externabtype ring;

with holes in

lugs

for plier as-

sembly prov ide a pr ac t i c a l

hanger or supp ort. for hose,

rods,

and

wires.

Ring

Work Piece

Retaining Ring

Retaining Ring

Retaining Ring Retaining Ring Retaining Ring

(seat

in

housing groove)

G

‘_ _otating ShaH

9 10

In ter lock ing extern a

I r i n g

serves as a loc king element for

a coupling that joins glass tub-

in g sections.

Interlocking external

ring

locks

two.piece h o u s i n g t h a t f i t s

around a rota ting shaft.

8/11/2019 86174_12


12- 18

More

Work for Round

Retaining Rings

Try

this

low-cost fastener for locking shafts and other parts. It will also

work as a shaft step for bearings and an actuating ring for switches.

Dominic J. Lalera

Conical wedge

Spring- fingered cage,

\

Unfocked

position

\Locked position

Piston

Rod\ r

ing

PISTON tS LOCKED in place on the rod

when drawn into place by means of

B

setscrew.

To

remove, slide the piston

aw ay f ro m the ring, then remove the ring,

LOCK A SHAFT by forcing

a

retaining

ring ov er the groove in the shaft. In

luck-

ing position, the springfingered cage

is

actuated by the conical wedge.

THIS SHAFT

STEP

for

a

rotating

bear-

ing i s quickly and simpla made hp groov-

ing the shaft t o acccpt

B

spring ring.

Countcrbore the shaft step to mare.

FLANGE ASSEMBLY

is

permanentlj

fastened by threading the n i r e into the

mating grooves through the Hangc. 1 h 1 g c

can rotate if wire doesn't protrude.

8/11/2019 86174_12



ASSEMBLE CYLINDER HEADS

and

siniilar parts to thin walls by means of

a

retaining ring and a locking block. 'i'ight-

ening the screws expands the ring.

THIS

SPRING-HELD shaft lock is a

basic application for retaining rings. Th e

best groove dimensions for round spring

rings are readily available from suppliers.

wifch

mounfing-bar

Male fhreaded

wedqe

\fnlemal

wedge\

THREE-P1ECE WEDGE lets the

shaft

i n n ~ e reelj unt i l the wedge i c lighfen d

by wrewing it

in.

I he round

rclnirring

ridg is

then forced into the groove.

SWITCH ACTUATORS of rnund refain-

ing rings offer

a simple solution

when

lmnianent sliaft steps

would

pr e m i t

assenibly problenls. Close the ring

gap.

8/11/2019 86174_12


12-20

Energy Absorber Squeezes Rings

to Cushion Shocks

A

novel shock absorber based on an easily demonstrated but li ttle-known

principle handles strains up to

1,000,OO Ib.

and performs through

100

cycles.

ake a metal clothes hanger and

T ull it apart until it breaks (as-

suming you have the super strength

needed for this feat). The hanger

elongates slightly until it fractures

and thus absorbs energy; the amo unt

of energy absorbed is a function of

the Eorce exerted and the amount of

stretch.

Now, take another hanger and

flex it back and forth. During each

flex, the metal deforms slightly; it

fatigues and eventually breaks.

Although the am ount of force ap-

plied at any one time during flexing

is not much, the total amount of en-

ergy absorbed far exceeds that ab-

sorbed when the hanger is ruptured

by a pure tensile force.

Principle rediscovered. This lit-

tle-known principle in energy ab-

sorption has been applied success-

fully and with dram atic results to the

development of a new shock ab-

sorber by Mechanics Research, Inc.

(MRI), El Segundo, Calif.

In a recent demonstration (left),

MRI sandwiched two soda crackers

between weights, each in its own

test fixture, and dropped them si-

multaneously. Baseballs on top of

each carriage provided added crack-

er load.

The left carriage struck a plain

rigid rod. The cracker, smashed un-

der im pact, was sprayed in all direc-

tions. The baseball rebounded,

springing into th e air.

The right carriage, however,

struck a novel shock absorber that

s effectively absorbs the impact en-

ergy that the carriage comes to a

smooth stop. The cracker remained

intact with narv a crumble. and the

baseball did

io t

rebound.’

Trapped

rings. The new absorb-

ers trap rolling rings (or sometimes

tube segments) between concentric

tubes under enough interference to

strain the metal in the rings beyond

its yield point. The interference

fit

may be

only

a few thousandths of a n

An internal wire ring aligns the

small rolling rings at each station.

Increasing either the ring wall thick-

ness or the interference increases

the energy absorber force. The unit

can be designed as either a otary

or

linear absorber.

The absorber cannot reset by it-

self. It needs springs to do

so.

But

it

Working ring

elements

Retainer

r ing

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1

Unidirectional Cyclic straining

to

failure to failure

strain range

-

c straining with

5

cycles

Plastic

Cyclic straining

Cyclic plastic straining absorbs more energy than unidirectional straining.

1

OFHC

Copper annealed

.- Nickel

A

annealed

0.1 1

10

100

1000 10,00

Cycles

t o failure

The

amount of plastic strain determines the number of cycles to failure.

24

ST

Aluminum,

347

Stainless steel

1

Cycles

to

failure

The number of cycles to failure influences total amount of energy absorption.

can be recycled if required and thu s

fills a need between one-shot sys-

tems, such as crushable honeycombs

and frangible tubes, an d the infinitely

reusable devices, such as hydraulic

shock absorbers.

Heavyweight capacity.

The ab-

sorbers can handle forces ranging

from 0.01 Ib. to

1,000,000

Ib., with

possible application in automotive

safety, spacecraft landers, aircraft

seats, and protection from blasts an d

earthquakes.

All-metal construction avoids the

undesirable features of fluids, seals,

and elastomers and permits long use

in difficult temperature and corro-

sion environments. Moreover, the

load-stroke behavior is relatively in-

sensitive to the effects of temp eratur e

and rate.

Cyclic strains. The underlying

principle is the cyclic straining

of

metal in the plastic range. This pro-

duces a hysteresis loop (left, top

drawing) that stabilizes after a

few

cycles. Repeated cycling results in

almost constant energy absorption

per cycle there is eventually fatigue

failure.

The specific energy absorption

(SEA) for

N

cycles to failure is

about N times the SE A for the o ne-

shot unidirectional straining to fail-

ure (middle, top drawing). Thus, a n

absorber designed to last, say, five

cycles to failure (right, top draw ing)

will be able to absorb

5

times

(roughly 2.24) the SEA for a uni-

directional straining.

Fo r example: Suppose the device

must handle 1000 cycles (strain cy-

cles) before failure. To do

so the

interference fit should cause a plas-

tic strain range

of

1.3

(0.013

in./

in., left middle chart) to obtain

maximum energy absorption of the

device.

The amount of SEA for

1000

cy-

cles is abou t

800,000

ft.-lb./lb. (bot-

tom ch art) . With a factor

of

one-half

to account for the n onuniform strain-

ing in the rings (th.e curv e is for

uniform straining), the average SEA

would be 4 00,00 0 ft.-lb./lb.

Thus, if the rolling rings in the

absorber add up t o 1 lb., they will ab-

sorb the energy

of

a 4000-lb. force

traveling through a foot of stroke

100

times.

8/11/2019 86174_12


12-22

Deflections of Perpendicularly

Loaded Split Circular Rings

M. M.

Lerncoe

FORMULAS FOR THE D E F L E C T I O N Of a Split uniform CirCu-

lar ring perpendicular to the plane of the r ing are given

for various positions of the load. Meth ods

of

developing

those formulas are demonstrated.

In Fig. 1

is

shown a split uniform circular ring of radius

R, loaded with a force P applied perpendicular to the plane

of the ring at the point B. At the po in t Q, the bending

moment

M

and the twisting moment T due to the load

P are respectively:

111

=

P

R

sin

p

-

0 )

(1)

T = P R [ l OS p

e) j (2)

Also, if there were a unit load at the point A, there

would be at point Q a bending moment m and a twisting

moment t du e to that unit load. These are given by the

following formula

nz =

R

sin a - )

t =

R

11- os

a-

e)]

3 )

(4)

From strain energy considerations, the deflection A

of

the point

A

can be formulated. If E is the modulus

of

elasticity and G is the shear modulus and if I is the moment

of inertia about the neutral axis of a cross-section, and

Fig. 1-Split circular ring loaded

by

a force

perpendicular to the

ring

at point B. The

deflection A at point A is

to

be catculated.

is the polar moment of inertia of a cross-section, the

formula is

A=j;:de j@

______

t R d 0

5)

Sub-

0 C J

Th e an g le

4

equals the smaller of angles a

or 8.

stituting

Eqs

I), 2 ) ,

( 3 )

and 4 ) in to

Eq

5 ) gives:

[I

-

OS a

-

]

[ l

-

OS

I

G

J p

-

]

From the trigonometric identities

sin a

-

e) sin

p

-

e =

4 cos a - B )

-

os

a

+ p

-

e)l

cos a e)

cos

p - = [COS a 8 ) + cos a+ 8 - e)l

The formula for A becomes:

1

s:

cos

a+

6

-

8 ) d

0

+

[1' os

a

- e)

d

B

2 G . I

0

-

/:

os a+ e) d 0

-

Integrating

Eq

6 ) gives

P

R3

E l

+ c o s a- 8 )

2

= -

[

1

in a

+ 8 -

4)

-

in a-

8)

4

I

P

R3

6 os a- )

-[ I

2

sin a+ 8 - 4) - in a

+

8)

4

-

+

4

+

in

( K

- 4) - in a

+ in 8 -

)

- in

8

(7)

From Eq

( 7 ) formulas can be developed for h for

Formulas for various positions

of

points A and B are

1

various positions of points A and B.

given below.

8/11/2019 86174_12



A

= Deflection at Point

A

P

=

Load at Point B

R

= Radius of Ring

= Modulus of Elasticity

G

= Shear Modulus

J = Cross-Section Polar Moment

of

Inertia

I = Cross-Section Polar Moment of Inertia About Neutral Axis

A

A-- R3 ( +g)

2

A 0

8/11/2019 86174_12


12-24

Improve Design

with

Retaining Rings

Waldes

Kohinoor

supplied the retaining

ri n s

for the assembly illustrated here.

Look

at the old

design,

look at the new design. What did retaining

rings

do? Well, by changing

the design to ret*

rings

these advantages are achieved:

1)

Six beveled r i n g w n e at each end of the three shaft bores-replace

24

hex-head bolts and eliminate drilling and tapping

24

holes in the cast housing.

2

Special gaskets’ needed to provide a proper seal between the end cap and

housing have been replaced by less expensive standard O-rings. Six facing o pera-

tions

on

the outside

of

the casting, required for the gasket seals, have been elimi-

nated. (O-ring grooves are an integral part of the redesigned cover plates.)

3) Twelve external ring s-& bowed, six flat-secure the h e r races of the

bearings

The rings are assembled

in

grooves machined simultaneously with the

sha ft cut-off and chamfering operations. They replace six threaded ring

nuts

and

six

lock washers and eliminate

12

ground diameters, six threading operations and

six

keyways

on

the

shaft.

4) Six basic internal rings, installed in grooves machined

in

the housing, elimi-

nate

six

machined shoulders and the need f or holding close axial tolerances

on

the

bearing bore and end cap.

Reusable following disassembly, the rings are assembled with special pliers,

and can be removed for field service.

0 LO

DESIGN

Lack

washer

i n

keywoy

NEW

DESIGN

Documents

86174_12