M7 Flashcards
The path of contact in involute gears
where the force/power is actually transmitted; it is a straight
imaginary line passing through the pitch point and tangent
to the base circle.
A. Front angle C. Pitch point
B. Line of action D. Principal reference plane
B
The train value of gear train is _______
the speed ratio.
A. Double C. Half of
B. Equal to D. Reciprocal of
D
he purpose of ______ is to
prevent gears from jamming together and making contact
on both sides of their teeth simultaneously.
A. Tooth fillet C. Backlash
B. Stress relieving D. All of these
C
The use of hardened steel for the mating
metal gear appears to give the best results and longer
operational life; the usual hardness is in the range of _____.
A. 300 to 400 BHN C. Over 400 BHN
B. Below 350 BHN D. Over 600 BHN
D
The sum of their addendums and
dedendums.
A. Full depth C. Width of space
B. Whole depth D. Working depth
B
They are used to change the rotary
motion to the reciprocating motion.
A. Helical gears C. Hypoid gears
B. Herringbone gears D. Rack gears
D
To avoid the breakage gear’s teeth, in
the absence of test values, the face width b of spur gear
teeth must be designed in this range.
A. 2.5𝑃𝑐 < b < 4𝑃𝑐 C. 2.5𝑃𝑑 < b < 4𝑃𝑑
B. 2.0𝑃𝑐 < b < 4𝑃𝑐 D. 2.0𝑃𝑑 < b < 4𝑃�
A
The reciprocal of diametral pitch
equivalent to the of the pitch diameter to the number of
teeth.
A. Clearance C. Lead
B. Involute D. Module
D
In involute teeth, the _________ or the
pressure angle ϕ is the angle between the line of action and
the line of tangent to the pitch circle.
A. Angle of approach C. Angle of recess
B. Angle of obliquity D. Arc of action
B
) It is the angle of action to the pitch angle
ratio in gear operation.
A. Contact ratio C. Gear ratio
B. Direct drive ratio D. Velocity ratio
A
A type of gear used to change the rotary
motion to reciprocating motion.
A. Helical gear C. Hypoid gear
B. Herringbone gear D. Rack gear
D
Spur and rack gears have this part that
have a common definition.
A. Clearance C. Pitch circle
B. Line of action D. Tooth thickness
A
It is the angle of action to the pitch angle
ratio in gear operation.
A. Contact ratio C. Gear ratio
B. Direct drive ratio D. Velocity ratio
A
It is caused by foreign matter such as grit or
metal particles or by a failure of the oil film at low speed
A. Abrasion C. Scoring
B. Corrosion D. Spalling
a
The portion of a gear tooth that projects
above or outside the pitch circle.
A. Addendum C. Tooth Space
B. Dedendum D. Tip Relief
A
The radial distance from the ________ to the clearance
circle is called working depth.
A. Addendum circle C. Dedendum circle
B. Pitch circle D. None of these
A
The desired quality in gear is:
A. Durability C. Strength
B. Quietness D. All of these
D
The lack of backlash in a spur gear
design/operation may result to:
A. Jamming C. Overloading
B. Overheating D. All of these
D
What will be the effect in bushing gears
without backlash?
A. Jamming C. Overload
B. Overheating D. All of these
D
n involutes teeth, the pressure angle is often
defined as the angle between the line of action and the line
of tangent to pitch circle. It is also known as the _________.
A. Angle of obliquity C. Arc of action
B. Angle of recess D. Helix angle
A
The amount by which the width of a tooth
space exceeds the thickness of the engaging tooth on the
pitch circles.
A. Backlash C. Clearance
B. Chordal thickness D. Undercut
A
It is necessary to care for errors and inaccuracies in the
spacing and to provide a space between the teeth for a
lubricant, and to allow for the expansion of the teeth with
temperature rise.
A. Backlash C. Fillet Radius
B. Clearance D. Fillet Space
A
The surface along the fillet curves or between
the fillet radius of the two adjacent tooth or a gear.
A. Bottom Land C. Flank
B. Fillet D. Top Land
A
The surface between the flanks of adjacent teeth.
A. backlash C. Bottom land
B. Flank D. Top land
C
The length of arc between the two sides of a
gear tooth on the pitch circle.
A. Axial Plane C. Circle Thickness
B. Chordal Curves D. Helix Angle
C
The distance from the center of one tooth of
a gear to the center next consecutive tooth measured on the
pitch.
A. Circular Pitch C. Diametral Pitch
B. Circular Pitch D. Module
B
Tooth width measurement along the chord
at the pitch circle.
A. Chord Clearance C. Chordal Length
B. Chord Space D. Chordal Thickness
D
The arc of action to circular pitch or length of
action to base pitch.
A. Approach C. Arc of approach
B. Arc of action D. Contact ratio
D
The depth of tooth space below the pitch
circle.
A. Dedendum C. Tooth depth
B. Full Depth D. Working Depth
A
The portion of a gear tooth space that is cut
below the pitch circle and is equal to the addendum plus the
clearance
A. Addendum C. Root
B. Dedendum D. Tooth Space
B
A circle bounding the bottom of the teeth
A. Addendum Circle C. Dedendum Circle
B. Addendum Cylinder D. Pitch Circle
C
The number of teeth per inch of pitch
diameter and which gives some indications of the size of the
gear teeth.
A. Circular Pitch C. Module
B. Diametral Pitch D. Pitch Circle
B
The ratio of the number of teeth to the
number of mm of pitch diameter equals number of gear
teeth to each mm pitch diameter.
A. Circular Pitch C. English Module
B. Diametral Pitch D. Module
B
Actual torque ratio of a gear set divided by
its gear ratio.
A. Approach ratio C. Contact ratio
B. Clearance D. Efficiency
D
In gear design, the ratio of pitch diameter, in
inches to the number of teeth is called:
A. Circular Pitch C. English Module
B. Diametral Pitch D. Module
C
It is the advance of the tooth in the face width
divided by circular pitch.
A. Advance ratio C. Profile ratio
B. Face contact ratio D. Speed ratio
B
The concave portion of tooth profile where it
joints the bottom of the tooth filler curve is called:
A. Bottom depth C. Fillet curve
B. Fillet D. Fillet radius
C
For gear cutting which cutter is used?
A. End mill cutter C. Plain milling cutter
B. Form relieve cutter D. All of the above
B
It is the extra tooth in gear, which is used to
distribute the wear more evenly.
A. Added tooth C. Hunting tooth
B. Dummy tooth D. Tooth profile
C
The distance a helical gear or worm would
thread along its axis in one revolution if it free to move
axially is called:
A. Land C. Length of action
B. Lead D. Length of contact
B
The path of contact in involute gears
where the force/power is actually transmitted; it is a straight
imaginary line passing through the pitch point and tangent
to the base circle.
C. Front angle C. Pitch point
D. Line of action D. Principal reference plane
D
The distance between the teeth measured on
the pitch surface along a normal to the helix.
A. Lead C. Normal circular pitch
B. Lead angle D. Pitch
C
In case of gears the addendum is given by:
A. One module C. 2.16 × module
B. π/2 × module D. 1.25 / module
A
Which of the following is an example of
rectilinear translation?
A. Locomotive wheels C. Rack gear
B. Piston of an engine D. Jack screw
B
A circle the radius of which is equal to the
distance from the gear axis to the pitch point.
A. Base Circle C. Pitch Circle
B. Outside Circle D. Root Circle
C
An imaginary circle passing through the
points at which the teeth of the meshing gears contact each
other.
A. Addendum Circle C. Dedendum Circle
B. Base Circle D. Pitch Circle
D
The size of gear is usually specified by ______.
A. Circular pitch C. Pitch diameter
B. Diametral pitch D. Pressure angle
C
It is known as the diameter of the pitch circle.
A. Circular pitch C. Diametral pitch
B. Diametral clearance D. Pitch diameter
D
In the Lewis equation, the working stress
depends on its:
A. Load conditions C. Tooth material
B. Pitch line velocity D. All of these
D
In a pair of gears, _____ is the plane
perpendicular to the axial plane and tangent to the pitch
surface.
A. Pitch C. Pitch Plane
B. Pitch Circle D. Pitch point
C
If a set of spur gears are made, installed, and
lubricated properly, they normally may be subjected to
failures like:
A. Pitting C. Surface fatigue
B. Scouring D. Breakage
A
A type of gear used to change the rotary
motion to reciprocating motion.
A. Helical gear C. Hypoid gear
B. Herringbone gear D. Rack gear
D
A circle coinciding with a tangent to the
bottom of the tooth space.
A. Addendum circle C. Pitch circle
B. Dedendum circle D. Root circle
D
It occurs when the oil film fails but, in this
case, the load and speed are so high that the surface metal
is melted and the metal is melted and the metal is smeared
down the profile.
A. Abrasion C. Scoring
B. Corrosion D. Spalling
C
The effects in bushing gears without backlash are the
following, EXEPT:
A. Jamming C. Overloading
B. Overheating D. Sliding
D
The space between the adjacent teeth measured along the
pitch circle.
A. Clearance C. Space width
B. Flank D. Top land
C
) It is a surface fatigue of greater extent than
pitting that is the flakes are much larger. This type of failure
occurs in surface-hardened teeth.
A. Abrasion C. Scoring
B. Corrosion D. Spalling
d
Interchangeability is possible only in this type of gear.
A. Bevel gear C. Spur gear
B. Helical gear D. Worm gear
C
Which of the following is a single measure
that combines the external dynamic load of an application
with a gear drive’s reliability and operating life?
A. Life factor C. Reliability factor
B. Ratio factor D. Service factor
C
How are gears for watches generally
manufactured?
A. Die casting C. Power metallurgy process
B. Machining on hobber D. Stamping
D
) It is the average tangential force on the teeth
is then obtained from the horsepower
A. Pressure load C. Tangential load
B. Separation load D. Total load
C
The distance of the tooth, which is equal to
the sum of the addendum and dedendum is known as:
A. Dedendum C. Whole depth
B. Full depth D. Working depth
C
The space between the adjacent teeth is
called:
A. Backlash C. Tooth
B. Flank D. Width
D
The total depth of a tooth space, equal to
addendum plus dedendum.
A. Dedendum C. Whole Depth
B. Full Depth D. Working Depth
C
n case of gears, the addendum is given by:
A. 1 × module C. 1.57 x module
B. 2.157 x module D. 1.25 x module
A
The _____ full depth teeth have the
advantages of the greater capacity and less interference
trouble.
A. 14.5° C. 24°
B. 20° D. 30°
B
The service factor of a gear may be taken as
__ is an electric motor drives a centrifugal blower
A. 1 C. 3
B. 2 D. 4
A
Buckingham says that mating phenolic gears
with steel of BHN less than ____ leads to excessive abrasive
wear.
A. 200 C. 400
B. 300 D. 500
D
For moderate speed of mating gears, the
ideal ratio of contact is:
A. 1.0 – 1.3 C. 1.25 – 4.0
B. 1.25 – 1.45 D. 1.35 – 1.55
C
In designing gears of power transmission,
consider and efficiency of _____ as recommended.
A. 85% or more C. 96% or more
B. 89% or more D. 98% or more
D
In usual spur gearing, the:
A. Pitch circle and base circle are the same
B. Tooth outline are always cycloidal curves
C. Tooth outlines are usually involute curves
D. Working depth induces clearance
C
According to the law of gearing:
A. Clearance between mating teeth should be provided
B. Dedendum should be equal to 1.57 × module
C. Teeth should be involute type
D. None of these
D
For an evenly and uniform wear on each
meshing gear tooth, the ideal design practice is to consider
a:
A. Hardening of each tooth
B. Heat treatment of the gears
C. Hunting tooth addition
D. Wear resistance alloy addition to tooth gears
C
Which of the following is a single measure
that combines the external dynamic load of an application
with a gear drive’s reliability and operating life?
A. Life factor C. Reliability factor
B. Ratio factor D. Service factor
D
In spur gears, the flank of the tooth is:
A. The curve forming face and flank.
B. The part of the tooth surface lying below the pitch
surface
C. The surface of the top of the tooth
D. The width of the gear tooth measured axially along the
pitch surface
B
When the pitch line speed is above 8,000
fpm, the teeth should be _______.
A. Ground after hardening
B. Should be cooled in air
C. Should not be quenched after hardening`
D. None of these
A
The condition for interchangeability of involute gear system
that all gears:
A. Have the same addendum
B. Have the same angle of obliquity
C. Have the same pitch
D. All of these
D
This factor accounts for survival rates other than 99%.
C. Life factor C. Reliability factor
D. Ratio factor D. Service factor
C
What is the backlash of a pinion if Pd = 5?
A. 0.075 in C. 0.15 in
B. 0.125 in D. 0.175 in
D
. The contact ratio for gears is ______.
A. Zero C. Less than one
B. Greater than one D. Less than/equal to 1
B
If the center distance of the mating gears having involute
teeth is increased, then the pressure angle ________.
A. increases C. fluctuate
B. decreases D. remains unchanged
A
The portion of the common tangent to the base circles along
which contact between mating involutes occurs.
A. Line of action C. Pressure angle
B. Arc of action D. Friction angle
A
The distance between similar sides of adjacent teeth
measured on the pitch line is called:
A. Pitch diameter C. Axial pitch
B. Diametral pitch D. Circular pitch
D
Surface endurance limit of gear material is dependent on
its:
A. Modulus of elasticity C. Elastic strength
B. BHN D. Yield strength
B
n rack gear, circular pitch is called:
A. Diametral pitch C. Pitch diameter
B. Linear pitch D. Module
B
This is equal to twice the addendum.
A. Working depth C. Clearance
B. Backlash D. Whole depth
A
The meaning of module in a gearing system is:
A. Diametral pitch C. Measure
B. Circular pitch D. Backlash
C
In a pair of gears, spur, or bevel, the smaller of the gears is
often called:
A. Bull Gear C. Worm
B. Gear D. Pinion
D
A _________ is a cylinder with teeth resembling those of
acme thread.
A. Bull gear C. Gear train
B. Pinion D. Worm
D
The gears on camshaft and crankshaft are known by this
term.
A. Lining gears C. Aligning gears
B. Timing gears D. Tuning gears
B
The ________ is equal to the tooth thickness plus the space
width.
A. Diametral pitch C. Circular pitch
B. Pitch diameter D. Pitch circle
C
It is standard practice to assume that the thickness of the
tooth measured sound the pitch circle is exactly ________
the circle path.
A. One-half C. One-third
B. One-fourth D. One-fifth
A
An imaginary circle passing through the points at which the
tooth of the meshing gears contacts each other.
A. Diametral pitch C. Circular pitch
B. Pitch diameter D. Pitch circle
D
A machine that makes gear teeth by means of a
reciprocating cutter that rotates slowly with the work.
A. Lathe machine C. Gear cutter
B. Planer machine D. Gear shaper
D
The minimum recommended worm pitch diameter is ¼ in
and the maximum is:
A. 1 in C. 3 in
B. 2 in D. 4 in
B
The amount by which the width of a tooth space exceeds
the thickness of the engaging tooth on the pitch circles.
A. Backlash C. Thickness
B. Flank D. Whole depth
A
The height of tooth above pitch circle or radial distance
between pitch circles and top land of the tooth is called:
A. Addendum C. Face width
B. Dedendum D. Whole depth
A
For moderate speed of mating gears, what is the ideal
contact ratio?
A. 1.0 to 2.5 C. 2.0 to 4.5
B. 1.25 to 4.0 D. 3.0 to 5.0
B
A __________ is one thicker in proportion to its length than
the involute tooth.
A. 20° Stub tooth C. 14.5° Full depth
B. 20° Full depth D. 25° Full depth
A
The product of circular pitch and diametral pitch.
A. π C. 2π
B. π/2 D. π/3
A
