2 Https en Wikipedia Org Wiki List of Gear Nomenclature

7/25/2019 2 Https en Wikipedia Org Wiki List of Gear Nomenclature

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List of gear nomenclatureFrom Wikipedia, the free encyclopedia

It has been suggested that portions of Gear#Nomenclaturebe splitfrom it

and mergedinto this article. (Discuss)

This relies largely or entirely upon a single source. Relevant

discussion may be fo und on the talk page. Please help improve this article

by introducing citationsto additional sources. (October 2012)

Contents

1 Addendum

2 Addendum angle

3 Addendum circle

4 Pressure Angle

5 Apex to back

6 Back angle

7 Back cone

8 Back cone distance

9 Backlash

10 Base circle

11 Base cylinder

12 Base diameter

13 Bevel gear

14 Bull gear

15 Center distance

16 Central plane

17 Composite action test

18 Cone distance

19 Conjugate gears

20 Crossed helical gear

21 Crossing point

22 Crown circle

23 Crowned teeth

24 Dedendum angle

25 Equivalent pitch radius

26 Face (tip) angle

27 Face cone

28 Face gear

29 Face width

30 Form diameter

31 Front angle

32 Front cone

33 Gear center

34 Gear range

35 Heel

36 Helical rack

37 Helix angle

38 Herringbone gear

39 Hobbing

40 Index deviation

41 Inside cylinder

42 Inside diameter

43 Involute gear

44 Involute polar angle

45 Involute roll angle

46 Involute teeth

47 Lands

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47.1 Bottom land

47.2 Top land

48 Lead

49 Line of centers

50 Mounting distance

51 Normal module

52 Normal plane

53 Offset

54 Outside cylinder

55 Outside diameter

56 Pinion

57 Pitch angle

58 Pitch circle

59 Pitch cone

60 Pitch cylinder

61 Pitch helix

61.1 Base helix

61.2 Base helix angle

61.3 Base lead angle

61.4 Outside helix

61.5 Outside helix angle

61.6 Outside lead angle

61.7 Normal helix

62 Pitch line

63 Pitch point

64 Pitch surfaces

65 Planes

65.1 Pitch plane

65.2 Transverse plane

66 Principal directions

67 Profile angle

68 Profile radius of curvature

69 Rack and pinion

70 Radial composite deviation71 Root angle

72 Root circle

73 Root cone

74 Root cylinder

75 Shaft angle

76 Spiral gear

77 Spiral bevel gear

78 Spur gear

79 Spur rack

80 Standard pitch circle

81 Standard pitch diameter

82 Standard reference p itch diameter83 Test radius

84 Throat diameter

85 Throat form radius

86 Tip radius

87 Tip relief

88 Tooth surface

89 Worm drive

90 See also

91 References

Addendum[edit]

The addendumis the height by which a too th o f a gear projects beyond (outs ide fo r external, or inside fo r

internal) the standard pitch circleor pitch line; also, the radial distance between the pitch diameter and the

outside diameter.[1]
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Principal dimensio ns

Internal gear diameters

Root circle

Apex to back exam ples


Addendum angle [edit]

Addendum anglein a bevel gear, is the angle between elements o f the f ace cone and pitch cone.[1]

Addendum circle [edit]

The addendum circle coincides with the to ps of the teeth of a gear and is

concentric with t he st andard (ref erence) pitch circleand radially distant f rom it by

the amount of the addendum. For external gears, the addendum circle lies on t he

outside cylinder while on internal gearsthe addendum circle lies on t he internal

cylinder.[1]

Pressure Angle [edit]

Main article:Angle of pressure

Apex to back [edit]

Apex to back, in a bevel gear or hypoid gear, is the

distance in the direction of the axis fro m the apex of t he

pitch cone to a locating surface at the back of the blank.[1]

Back angle [edit]

The back angleof a bevel gear is the angle between an element o f the back cone and a plane of ro tation, and

usually is equal to the pitch angle.[1]

Back cone [edit]

The back coneof a bevel or hypoid gear is an imaginary cone tangent to the outer

ends of the teeth, with its elements perpendicular to those of the pitch cone. The

surf ace of t he gear blank at the outer ends of the teeth is custo marily formed to

such a back cone.[1]
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Involute teeth

Base cylinder

Base diameter

Back cone distance [edit]

Back cone distance in a bevel gear is t he distance along an element of the back cone fro m its apex to t he

pitch cone.[1]

Backlash [edit]

Main article: Backlash (engineering)

In mechanical engineering, backlash is the striking back of connected wheels in a piece of mechanism when

pressure is applied. Another source def ines it as the maximum distance thro ugh which one part of something

can be moved without moving a connected part . It is also called lash or play. In the context o f gears, backlash

is clearance between mating components, or t he amount of lost motion due to clearance or slackness when

movement is reversed and contact is re- established. In a pair of gears, backlash is the amount o f clearance

between mated gear teeth.

Backlash is unavoidable for nearly all reversing mechanical couplings, although its ef f ects can be negated.

Depending on the application it may or may not be desirable. Reasons f or requiring backlash include allowing

for lubricationand thermal expansion, and to prevent jamming. Backlash may also result f rom manufacturing

errors and deflectionunder load.

Base circle [edit]

The base circleof an involute gearis the circle f rom which involute t oot hprofilesare derived.[1]

Base cylinder [edit]The base cylindercorresponds to the base circle, and is the cylinderf rom which

involute t oot hsurfaces are developed.[1]

Base diameter [edit]

The base diameterof an involute gearis the diameter of the base circle.[1]

Bevel gear [edit]

Main article: Bevel gear

Bull gear [edit]

The t erm bull gearis used to refer to t he larger of two spur gearsthat are in engagement in any machine. The
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Center distance

Central plane

Schematic of the composite action

test

Cone distance

smaller gear is usually referred to as a pinion.[2]

Center distance [edit]

Center distance(operating) is t he shortest distance between non-intersecting

axes. It is measured along the mutual perpendicular to t he axes, called the line of

centers. It applies to spur gears, parallel axis or crossed axis helical gears, and

worm gearing.[1]

Central plane [edit]

The central planeof a worm gear is perpendicular to the gear axis and contains

the common perpendicular of the gear and worm axes. In the usual case with axes

at right angles, it contains the worm axis.[1]

Composite action test [edit]

The composite action test (double flank) is a method o f inspection in

which the work gear is rolled in tight double f lank contact with a master

gear or a specif ied gear, in order to determine (radial) composite

variations (deviations). The compos ite action tes t must be made on a

variable center distance composite action test device.[1]

Cone distance [edit]

Cone distancein a bevel gear is the general term fo r the distance alongan element of the pitch cone f rom the apex to any given pos ition in the

teeth.[1]

Outer cone distance in bevel gears is the distance f rom the apex of the

pitch cone to the outer ends of the teeth. When not otherwise specif ied,

the short term cone distance is understood to be outer cone distance.

Mean cone distance in bevel gears is the distance f rom the apex of the

pitch cone to the middle of the face width.

Inner cone distance in bevel gears is the distance f rom the apex of the

pitch cone to the inner ends of the teeth.

Conjugate gears [edit]

Conjugate gearstransmit uniform rotary motion from one shaft to another by means of gearteeth. The

normals to the prof iles of these teeth, at all points of contact, must pass through a fixed point in the common

centerline of the two shafts.[1]Usually conjugate gear toot h is made to s uit the prof ile of other gear which is
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Crowned gear

Back cone equivalent

not made based on standard practice.

Crossed helical gear [edit]

A crossed helical gearis a gear that o perate on non- intersecting, non-parallel axes.

The term crossed helical gears has superseded the term spiral gears. There is t heoretically point contact

between the teeth at any instant. They have teeth of the same or diff erent helix angles, of the same or

opposite hand. A combination o f spur and helical or o ther types can operate on crossed axes.[1]

Crossing point [edit]

The crossing point is the point of intersection of bevel gear axes; also the apparent point of intersection of

the axes in hypoid gears, crossed helical gears, worm gears, and of f set f ace gears, when projected to a plane

parallel to bo th axes.[1]

Crown circle [edit]

The crown circlein a bevel or hypoid gear is t he circle of intersection of the back cone and face cone.[1]

Crowned teeth [edit]

Crowned teet hhave surf aces modif ied in the lengthwise direction to

produce localized contact o r to prevent contact at their ends.[1]

Dedendum angle [edit]

Dedendum anglein a bevel gear, is the angle between elements of the root cone and pitch cone.[1]

Equivalent pitch radius [edit]

Equivalent pit ch radiusis the radius o f the pitch circle in a cross

section of gear teeth in any plane other than a plane of rotation. It is

properly the radius of curvature of the pitch surface in the given cross

section. Examples o f such sections are the t ransverse section of bevel

gear teeth and the normal section o f helical teeth.

Face (tip) angle [edit]

Face (tip) anglein a bevel or hypoid gear, is the angle between an element o f the f ace cone and its axis.[1]

Face cone [edit]

The face cone, also known as the tip coneis the imaginary surface that coincides with the tops of the teeth

of a bevel or hypoid gear.[1]

Face gear [edit]

A face gearset typically consist s o f a disk-shaped gear, grooved on at least one f ace, in combination with a

spur, helical, or conical pinion. A f ace gear has a planar pitch surf ace and a planar root surf ace, both of which

are perpendicular to the axis o f rotat ion.[1]It can also be referred to as a face wheel, crown gear, crown

wheel, contrate gearor contrate wheel.
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Face worm gear

Face width

Form diameter

Face width [edit]

The face widthof a gear is t he length of teeth in an axial plane. For

double helical, it does not include the gap.[1]

To tal f ace width is the actual dimension o f a gear blank including the

portion t hat exceeds the eff ective face width, o r as in double helical

gears where the total face width includes any distance or gap separating

right hand and lef t hand helices.

For a cylindrical gear, ef f ective face width is t he portion t hat contacts

the mating teeth. One member of a pair of gears may engage only a

portion of its mate.

For a bevel gear, dif f erent definitions f or ef f ective face width are

applicable.

Form diameter [edit]

Form diamet eris t he diameter o f a circle at which the trochoid (f illet curve)

produced by the to oling intersects, o r joins, the involute or specif ied prof ile.

Although these terms are not pref erred, it is also known as the t rue invo lute f ormdiameter (TIF), start of involute diameter (SOI), or when undercut exists, as the

undercut diameter. This diameter cannot be less than the base circle diameter.[1]

Front angle [edit]

The front angle, in a bevel gear, denotes the angle between an element o f the f ront cone and a plane of

rotation, and usually equals the pitch angle.[1]

Front cone [edit]

The front coneof a hypoid or bevel gearis an imaginary cone tangent to the inner ends o f the teeth, with its

elements perpendicular to those of the pitch cone. The surface of the gear blank at t he inner ends of the teeth

is customarily f ormed to s uch a fro nt cone, but so metimes may be a plane on a pinion or a cylinder in a nearly

flat gear.[1]

Gear center [edit]

A gear centeris the center of the pitch circle.[1]

Gear range [edit]The gear rangeis dif f erence between the highest and lowest gear ratios and may be expressed as a

percentage (e.g., 500%) o r as a rat io (e.g., 5:1).

Heel [edit]
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Heel and toe

The heelof a too th on a bevel gear or pinion is the portion of the toot h

surf ace near its outer end.

The toe of a too th on a bevel gear or pinion is the portion of the toot h

surf ace near its inner end.[1]

Helical rack [edit]

A helical rackhas a planar pitch surface and teeth that are oblique to the direction o f motion.[1]

Helix angle [edit]

Helix angleis t he angle between the helical too th f ace and an equivalent spur tooth f ace. For the same lead,

the helix angleis greater f or larger gear diameters. It is understo od t o be measured at t he standard pitch

diameter unless otherwise specif ied.

Main article: Helix angle

Herringbone gear [edit]

Main article: Herringbone gear

Hobbing [edit]

Hobbing is a machining process for making gears, splines, and sprockets using a cylindrical tool with helical

cutting teeth known as a hob.

Main article: Hobbing

Index deviation [edit]

The displacement of any toot h f lank f rom its theoretical position, relative to a datum tooth f lank.

Distinct ion is made as to t he direction and algebraic sign of this reading. A condit ion wherein the actual toot h

f lank pos ition was nearer to t he datum to oth f lank, in the specified measuring path direction (clockwise o r

counterclockwise), than the theoretical position would be considered a minus (-) deviation. A condition wherein

the actual tooth f lank position was f arther fro m the datum tooth f lank, in the specified measuring path

direction, t han the t heoretical position would be cons idered a plus (+) deviation.

The direction of to lerancing f or index deviation along the arc of the t olerance diameter circle within the

transverse plane.[1]

Inside cylinder [edit]

The inside cylinderis the surf ace that coincides with the tops of the teeth o f an internal cylindrical gear.[1]
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Diameters, Internal Gear

Internal gear diameters

Involute polar angle

Involute roll angle

Inside diameter [edit]

Inside diameteris the diameter of the addendum circle of an internal

gear, this is also known as minor diamet er.[1]

Involute gear [edit]

Main article: Involute gear

Involute polar angle [edit]

Expressed as , t he involute polar angleis t he angle between a radius vecto r to a

point, P, on an involute curve and a radial line to the intersection,A, of the curve

with the base circle.[1]

Involute roll angle [edit]

Expressed as , the involute roll angle is the angle whose arc on the base circle

of radius unity equals the tangent of the pressure angle at a selected point on the

involute.[1]

Involute teeth [edit]

Involute teethof spur gears, helical gears, and worms are those in which the profile in a transverse plane

(exclusive of the f illet curve) is t he involute o f a circle.[1]
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Involute teeth

Top and bottom lands

Mounting distance

Lands [edit]

Bottom land [edit]

"Bottom land" redirects here. For information on the similar term "bottomland", see

Upland and lowland (freshwater ecology).

The bott om landis the surf ace at the botto m of a gear too th space adjoining the

fillet.[1]

Top land [edit]

Top landis the (sometimes f lat) surf ace of the top of a gear too th.[1]

Lead [edit]

Leadis the axial advance of a helix gear tooth during one complete turn (360), that is, t he Leadis the axial

travel (length along the axle) for one single complete helical revolut ion about t he pitch diameter of the gear.

Lead angleis 90 to the helix anglebetween the helical too th f ace and an equivalent spur t oo th f ace. For the

same lead, the lead angleis larger f or smaller gear diameters. It is understood t o be measured at t he standard

pitch diameter unless ot herwise specified.

A spur gear t oo th has a lead angleof 90, and a helix angleof 0.

See: Helix angle

Main article: Lead (engineering)

Line of centers [edit]

The line of centersconnects the centers o f the pitch circles o f two engaging gears; it is also the common

perpendicular of the axes in crossed helical gears and wormgears. When one of the gears is a rack, the line of

centers is perpendicular to its pitch line.[1]

Mounting distance [edit]

Mounting distance, for assembling bevel gears or hypoid gears, is the

distance from the crossing point of the axes to a locating surface of a

gear, which may be at either back or f ront .[1]

Normal module [edit]

Normal moduleis the value of the module in a normal plane of a helical gear or worm.[1]

Normal plane [edit]

A normal planeis normal to a tooth surf ace at a pitch point, and perpendicular to t he pitch plane. In a helical

rack, a normal plane is no rmal to all the t eeth it intersect s. In a helical gear, however, a plane can be normal to
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Planes at a pitch point

on a helical tooth

Offset

Cylindrical surfaces

Wormgear diameters

only one to oth at a po int lying in the plane surf ace. At such a point, the normal

plane contains the line normal to t he too th surf ace.

Important pos itions o f a normal plane in too th measurement and tool design of

helical teeth and worm threads are:

1. the plane normal to the pitch helix at s ide of to oth;

2. the plane normal to the pitch helix at center of tooth;

3. the plane normal to the pitch helix at center of space between two teeth

In a spiral bevel gear, one of the pos itions o f a normal plane is at a mean point and the plane is normal to t he

too th trace.[1]

Offset [edit]

Offset is t he perpendicular distance between the axes of hypoid gears

or offset face gears.[1]

In the diagram to the right, (a) and (b) are referred to as having an

offset below center, while those in (c) and (d) have an of f set above

center. In determining the direction of of f set, it is customary to look at

the gear with the pinionat the right. For below center of f set t he pinion

has a left hand spiral, and for above center of f set t he pinion has a right

hand spiral.

Outside cylinder [edit]

The outside (tip or addendum) cylinderis the surf ace that coincides with

the to ps of the teeth o f an external cylindrical gear.[1]

Outside diameter [edit]

The outside diamete rof a gear is t he diameter o f the addendum (tip)circle. In a bevel gearit is the diameter of the crown circle. In a throated

wormgearit is t he maximum diameter of the blank. The term applies t o

external gears, this is can also be known from major diameter.[1]

Pinion [edit]
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Angle relationshipsAngles

Pitch Angle examples

Pitch cones

Pitch cylinder

Tooth helix

Main article: Pinion

Pitch angle [edit]

Pitch anglein bevel gears is the angle

between an element of a pitch cone and its

axis. In external and internal bevel gears, the

pitch angles are respectively less than and

greater than 90 degrees.[1]

Pitch circle [edit]

A pitch circle(operating) is the curve of intersection of a pitch surf ace of revolution and a plane of rotation.

It is the imaginary circle that ro lls without slipping with a pitch circle of a mating gear.[1]These are the outlines

of f the imaginary smooth roller or f riction discs in every pair of mating gears. Many important measurements

are taken on and from this circle.[1]

Pitch cone [edit]

A pitch coneis the imaginary cone in a bevel gear that rolls without slipping on a

pitch surface of another gear.[1]

Pitch cylinder [edit]

A pitch cylinderis the imaginary cylinder in a spur or helical gear that rolls without

slipping on a pitch plane or pitch cylinder of another gear.[1]

Pitch helix [edit]

The pitch helixis the intersection of the tooth surface and the pitch

cylinder of a helical gear or cylindrical worm.[1]

Base helix [edit]

The base helixof a helical, involute gear or involute worm lies on its base cylinder.

Base helix angle [edit]

Base helix angleis the helix angle on the base cylinder of involute helical teeth or threads .
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Normal helix

Pitch surfaces

Base lead angle [edit]

Base lead angle is the lead angle on the base cylinder. It is the complement of the base helix angle.

Outside helix [edit]

The outside (tip or addendum) helixis the intersection of the tooth surface and the outside cylinder of a

helical gear or cylindrical worm.

Outside helix angle [edit]

Outside helix angleis the helix angle on the outside cylinder.

Outside lead angle [edit]

Outside lead angleis the lead angle on the outs ide cylinder. It is the complement o f the outs ide helix angle.

Normal helix [edit]

A normal helixis a helix on the pitch cylinder, normal to the pitch helix.

Pitch line [edit]

The pitch linecorresponds, in the cross section of a rack, to the pitch circle (operating) in the cross section

of a gear.[1]

Pitch point [edit]

The pitch point is the point o f tangency of two pitch circles(or o f a pitch circle and pitch line) and is o n the

line of centers.[1]

Pitch surfaces [edit]

Pitch surf aces are the imaginary planes, cylinders, or cones that roll

together without slipping. For a const ant velocity ratio, the pitch

cylinders and pitch cones are circular.[1]
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Pitch cones

Pitch planes

Principal directions

Fillet radius

Total composite variation trace

Planes [edit]

Pitch plane [edit]

The pitch planeof a pair of gears is the plane perpendicular to the axial plane and

tangent to the pitch surf aces. A pitch plane in an individual gear may be any plane

tangent to its pitch surface.

The pitch plane of a rack or in a crown gear is the imaginary planar surf ace that

rolls without slipping with a pitch cylinder or pitch cone of another gear. The pitch

plane of a rack or crown gear is also the pitch surf ace.[1]

Transverse plane [edit]

The transverse planeis perpendicular to the axial plane and to the pitch plane. In gears with parallel axes, t he

transverse and the plane of rotat ion coincide.[1]

Principal directions [edit]

Principal directions are directions in the pitch plane, and correspond to

the principal cross sections of a tooth.

The axial direction is a direction parallel to an axis.

The transverse direction is a direction within a transverse plane.

The normal direction is a direction within a normal plane.[1]

Profile angle [edit]

Main article: Profile angle

Profile radius of curvature [edit]

Profile radius of curvatureis the radius of curvature of a toot h

prof ile, usually at t he pitch point o r a point o f contact. It varies

continuously along the involute prof ile.[1]

Rack and pinion [edit]

Main article: Rack and pinion

Radial composite deviation [edit]

Tooth-to-tooth radial composite deviation(double f lank) is the

greatest change in center distance while the gear being tested is rotated

through any angle of 360 degree/z during double f lank composite action

test.

Tooth-to-tooth radial composite tolerance (double flank) is the

permissible amount of tooth-to-tooth radial composite deviation.

To tal radial composite deviation (double flank) is the t otal change in
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External gear

Internal gear

Roo t Circles for internal & external gears


Shaft angle

center distance while the gear being tes ted is ro tated one complete revolut ion during a double f lank compos ite

action test .

To tal radial composite tolerance (double flank) is the permissible amount of to tal radial composite deviation.[1]

Root angle [edit]

Root anglein a bevel or hypoid gear, is the angle between an element o f the root cone and its axis.[1]

Root circle [edit]

The root circlecoincides with the bot to ms

of the tooth spaces.[1]

Root cone [edit]

The root coneis t he imaginary surface that coincides with the bot to ms

of the to oth spaces in a bevel or hypoid gear.[1]

Root cylinder [edit]

The root cylinderis t he imaginary surface that coincides with the bot toms of the too th spaces in a cylindrical

gear.[1]

Shaft angle [edit]

A shaft angleis t he angle between the axes o f two non-parallel gear

shafts. In a pair of crossed helical gears, the shaf t angle lies between

the oppositely rotating portions of two shafts. This applies also in the

case of worm gearing. In bevel gears, the shaft angle is the sum of the

two pitch angles. In hypoid gears, the shaf t angle is given when starting

a design, and it does no t have a f ixed relation t o t he pitch angles and

spiral angles.[1]

Spiral gear [edit]

See: Crossed helical gear.

Spiral bevel gear [edit]

Main article: Spiral bevel gear
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Spur gear

Spur gear [edit]

A spur gearhas a cylindrical pitch surf ace and teeth that are parallel to t he

axis.[1]

Spur rack [edit]

A spur rackhas a planar pitch surf ace and straight teeth t hat are at right angles to t he direction of motion.[1]

Standard pitch circle [edit]

The standard pitch circle is the circle which intersects the involute at the point where the pressure angle is

equal to the prof ile angle of the basic rack.[1]

Standard pitch diameter [edit]

The standard ref erence pitch diamete ris the diameter o f the s tandard pitch circle. In spur and helical gears,

unless otherwise specified, the standard pitch diameter is related to the number of teeth and the s tandard

transverse pitch. The diameter can be roughly estimated by taking the average of the diameter measuring the

tips of the gear teeth and the base of the gear teeth.[1]

The pitch diameter is usef ul in determining the spacing between gear centers because proper spacing of gears

implies tangent pitch circles. The pitch diameters of two gears may be used to calculate the gear ratio in the

same way the number of teeth is used.

Where is the to tal number of teeth, is the circular pitch, is the diametrical pitch, and is the helix

angle fo r helical gears.

Standard reference pitch diameter [edit]

The standard ref erence pitch diamete ris the diameter o f the s tandard pitch circle. In spur and helical gears,

unless otherwise specified, the standard pitch diameter is related to the number of teeth and the s tandard

transverse pitch. It is obtained as:[1]

Test radius [edit]

The test radius(Rr) is a number used as an arithmetic convention established to s implify the determination ofthe proper test distance between a master and a work gear f or a composite action test . It is used as a

measure of the ef f ective size of a gear. The tes t radius of the master, plus the tes t radius of the work gear is

the set up center distance on a composite action test device. Tes t radius is not the same as the operating

pitch radii of two t ightly meshing gears unless bo th are perfect and to basic or standard too th thickness.[1]
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Wormgear diameters

Tip radius

Tip relief

Profile of a spur gear

Notation and numbering for an

external gear

Throat diameter [edit]

The throat diamete ris the diameter of the addendum circle at the central plane of

a wormgear or of a double-enveloping wormgear.[1]

Throat form radius [edit]

Throat form radiusis t he radius o f the throat o f an enveloping wormgear or of a double-enveloping worm, in

an axial plane.[1]

Tip radius [edit]

Tip radiusis t he radius o f the circular arc used to join a side-cutting edge and an

end-cutting edge in gear cutting tools. Edge radius is an alternate term.[1]

Tip relief [edit]

Tip reliefis a modification of a too th prof ile whereby a small amount o f material is

removed near the tip of the gear toot h.[1]

Tooth surface [edit]

Notation and numbering for an

internal gear

The tooth surface (f lank) forms the side of a gear toot h.

[1]

It is convenient t o choose one f ace of the gear as the reference face and to mark it with the letter I. The

other non-ref erence f ace might be termed face II.

For an observer looking at the reference face, so that t he too th is seen with its t ip uppermost, the right f lank

is on the right and the left f lank is on the lef t. Right and lef t f lanks are denoted by the letters R and L
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respectively.

Worm drive [edit]

Main article: Worm drive

See also [edit]

Gear ratio

Sprocket

References [edit]

1. ^ abcdefghijklmnopqrstuvwxyzaaabacadaeafagahaiajakalamanaoapaqarasatauavawaxayazba

bbbcbdbebfbgbhbibjbkblbmbnbobpbqbrbsbtbubvbwGear Nomenclature, Definition of Terms with Symbols.

American Gear Manufacturers Assoc iation. p. 72. ISBN1-55589-846-7 . OCLC65562739 . ANSI/AGMA 1012-

G05.

2. ^To ny Casey, President Bull Gea r, Inc. "Bull Gear, Inc. - What is a Bull Gear!?" . Retrieved 4 January 2012.

Categories : Gears Mechanical engineering Technology-related lists
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