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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
Principal dimensio ns
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
Principal dimensio ns
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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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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