機器
big
black
circle
closeup
cog
cogwheel
connection
cutout
detail
device
element
engineering
equipment
flywheel
focus
gearing
greasy
heavy
industry
invention
iron
manufacture
mechanical
metal
motion
new
object
part
power
production
reliability
repair
rotating
round
shiny
solid
spin
steel
system
technical
teeth
torque
transmission
transmit
turn
wheel