Installation of Travel Motor

TM 10-3930-609-35

of brush springs that bear on brushes. At point where

b. Insert stud terminals through terminals on field

end of spring is raised off brush, spring balance should

coil assembly; apply flatwashers and insulating washers

read 3 to 4 pounds.

to stud terminals and insert stud terminals in holes of

motor ring. Place insulating bushing on stud terminals

Caution

and complete installation with insulating washers,

flatwashers, lockwashers and nuts.

Do not apply a voltage greater than

12 volts dc to motor unless motor

c. Press front bearing onto armature shaft and

has a load applied.

Motor will

insert armature into motor ring.

overspeed if operated at a higher

d. Press oil seal into rear yoke, install rear bearing

voltage without load.

in yoke and install retaining ring in groove of yoke.

e. Carefully slide rear yoke onto end of armature

l. With motor securely clamped to bench, apply 12

shaft and aline match marks with match marks on motor

volts dc to field terminals and 12 volts dc to brush

ring. Secure rear yoke to motor ring with studs,

terminals (brush terminal A1 positive and A2 negative).

lockwashers and nuts.

Check that motor rotation is clockwise when viewed

f. Place insulator, flatwashers, internal insulator

from commutator end of armature when field terminal

and insulating washer on threaded end of terminal stud

F2 is negative. Stop motor and reverse field polarity to

on both brush connector assemblies; assuring that

check that motor rotation reverses.

projection on internal insulator projects through slot in

m. Lightly stone commutator if excessive sparking

flat insulator.

Then insert both brush connector

is noted between brushes and commutation.

assembly stud terminals through holes in front yoke and

apply

insulating

bushings,

external

insulator,

n. Drive shouldered studs into front yoke.

flatwashers, lockwashers and nuts to both terminal

o. Attach yoke covers to shouldered studs and

studs. Tighten nuts securely.

secure opposite ends with screw, nut and lockwasher.

g. Install brushholders in front yoke with screws,

lockwashers, flatwashers and insulating bushings,

Caution

including an insulator between each brushholder and

Do not allow motor to operate at 36

yoke.

volts without torque loading. Motor

h. Assemble front yoke to motor ring, aline match

will

overspeed

and

may

marks and secure with four screws and lockwashers.

irreparably damaged.

i. Check that armature rotates freely without any

p. Install brake drum on motor shaft and clamp

evidence of binding before continuing assembly. If

motor securely to bench top. Apply a torque arm to

binding is detected, determine cause and correct trouble

brake drum. Torque arm must be capable of applying

before proceeding.

increasing load to brake drum.

Connect motor

electrically as shown in figure 3-16. Test motor first at

j. Insert brush assemblies in brushholders and

no load; then, gradually apply torque load to armature

install brush springs to retain brush assemblies. Attach

stall. Motor performance characteristics must be shown

terminals on brush shunts and terminals on brush

in the following chart.

connector assemblies to brushholders with screws and

lockwashers.

k. Using a spring balance, check force of brush

springs against brushes by slowly applying force to ends

Voltage

Loading

Applied torque

Motor speed

Current

(steady)

36 volts de Equivalent to truck speed of 7 miles per

15 foot pounds

2,940 rpm 5%

120 amps 5%

hour with 2,000 pound load on forks

36 volts de Stalled rotor

100 foot pounds minimum

500 amps 5%

3-90. Installation of Travel Motor

Refer to paragraph 2-24 for installation procedure.

3-29