Other Products: Pawls & Ratchets, Involute Spline Shafts, Spline

579

Catalog Number of KHK Stock Gears

Material TypeS S45C RT Pawls and Ratchets

GC Gear Coupling V Involute Spline

Other Products

S V 20 - 200Total Length (200 mm) Major Diameter (20 mm) Type (Involute spline shafts)

Material (S45C)

Other Products

■ Feature Icons

The Catalog Number for KHK stock gears is based on the simple formula listed below. Please order KHK gears by specifying the Catalog Numbers. (Example)

RoHS Compliant Product

Stainless Product

Re-machinable Product

Resin Product

Finished ProductCopper Alloy Product

Heat Treated Product

Injection Molded Product

Ground GearBlack Oxide coated Product

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SRT・SRTB・SRT-CPawls & Ratchets

P2.09 ～ 12.56 Page 580

SV・SVIInvolute Spline Shafts,

Spline Bushings

m1.667 Page 588

GC・GC-IGear Couplings

m2, 2.5 Page 584

QSGA・QSGMaster Gears (Spur Gear)

m0.4 ～ 1 Page 592

KHK products are available from MARYLAND METRICSP.O. Box 261 Owings Mills, MD 21117 USA ph: (410)358-3130 (800)638-1830 fx: (410)358-3142 (800)872-9329 email: [email protected] http://mdmetric.com RFQ form: http://mdmetric.com/rfq.htm

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Characteristics of Pawls and Ratchets

● A simple structure used to restrict the rotational direction in one-way. ● The tips of pawls and the teeth of ratchets are induc-

tion hardened and therefore have superior durability.

SRT・SRTB・SRT-C

Ratchets・Pawls

■ Features

■ Points to observe during use

● No secondary operations can be performed on tooth areas including the bottom land (approx. 1 to 2 mm), due to gear teeth induction hardened.

● The pawls are designed to prevent reverse rotation. They are not suitable for use as driving ratchets or driving rotation.

● SRT2/ 3-C is manufactured using a lost wax casting method.● Regarding SRTB ratchets with hubs, please note the

direction of teeth, viewing from the hub side. KHK can produce ratchets which have the teeth pointed in the opposite direction as a custom order item.

Assembly example: KHK Stock Gears Sample Units

■ Bending strength of Ratchets

The allowable transmission forces Fb (N) of ratchets is the value calculated by the following formula.

Also, the SRT Ratchet's allowable torque T (N・m) for bending strength is calculated by the following formula.

T = Fb ・ rf

Where

Fb ＝ σb・b・e2

6・・

1h

1SF

＝ Bending stress (Assumed 225.55MPa)＝ Face width E (mm)＝ Root length (mm)

＝ Depth of teeth (H) (mm)＝ Safety factor (Assumed 2)＝ Tooth root radius (m)

σb

be

hSF

rf

e ＝ Depth of teeth (h) × tan 60－　　　　　360

No. of teeth (z)

→ rf ＝　　　　　　　　　　　Outside dia. D ー（2・h）2000

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Please see our web site for corrections on KHK Catalogs.

Ratchets & Pawls

Application

SRT Ratchet

SRT-C Pawls

Example: ratchets used for complete reverse prevention of worm gears *

SRT-C Pawls

SRT Ratchet

Motor

Example: SRT Ratchets used as a free-fall prevention mechanism of a lift device*

Lifti

ng D

evic

e

SRT・SRTB

* The illustration is a design example, not a design for machinery or a device in actual use.

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PawlsPitch 2.09～ 12.56SRT-C

I

E

A DH

J

T4

Specifications

Angle of teeth 60°

Material S45C

Heat treatment Induction hardened teeth

Tooth hardness 45～ 55HRC

Specifications

Angle of teeth 60°

Material S45C

Heat treatment Induction hardened teeth


Catalog No. Shape K (L) M (N) PWeight

（kg）SRT2/3-CSRT1-CSRT2-CSRT3-CSRT4-C

T5

58

101213

(8)(10)(12.5)(15)(18)

3039556580

(38)(49)(67.5)(80)(98)

612152025

0.0200.0570.130.230.38

Catalog No. Pitch No. of teeth ShapeBore Hub dia. Outside dia. Face width Hub width Total length Depth of teeth Center distance Mounting distance

A B D E F G H I JSRT2/3-50SRT2/3-60SRT2/3-80SRT2/3-90SRT2/3-100

2.09

50608090

100

T4

1010121212

―

33.34053.36066.6

6 ― 6 1

33.8435.5139.4841.7344.11

15.671925.672932.33

SRT1-50SRT1-60SRT1-80SRT1-90SRT1-100

3.14

50608090

100

T4

1215151515

―

50608090

100

12 ― 12 1.6

45.4848.2454.7358.3562.16

23.428.438.443.448.4

SRT2-30SRT2-40SRT2-50SRT2-60

6.28

30405060

T4

15151515

―6080

100120

15 ― 15 3.1

61.2366.2372.2879.14

26.936.946.956.9

SRT3-30SRT3-40SRT3-50

9.42304050

T4152020

―90

120150

20 ― 20 576.3285.1595.52

405570


12.56304050

T4202020

―120160200

25 ― 25 7.495.74

108.03122.37

52.672.692.6

SRTB2/3-50SRTB2/3-60SRTB2/3-80SRTB2/3-90SRTB2/3-100

2.09

50608090

100

T9

1010121212

2530354040

33.34053.36066.6

6 10 16 1

33.8435.5139.4841.7344.11

15.671925.672932.33

SRTB1-50SRTB1-60SRTB1-80SRTB1-90SRTB1-100

3.14

50608090

100

T9

1215151515

3540505050

50608090

100

12 12 24 1.6

45.4848.2454.7358.3562.16

23.428.438.443.448.4

SRTB2-30SRTB2-40SRTB2-50SRTB2-60

6.28

30405060

T9

15151515

50606065

6080

100120

15 14 29 3.1

61.2366.2372.2879.14

26.936.946.956.9

SRTB3-30SRTB3-40SRTB3-50

9.42304050

T9152020

758085

90120150

20 16 36 576.3285.1595.52

405570


12.56304050

T9202020

9090

100

120160200

25 18 43 7.495.74

108.03122.37

52.672.692.6

(N)

M

K

P

(L)60° FD

T5＊ FD has die-forged finish.

RatchetsPitch 2.09～ 12.56SRT・SRTB

① Due to gear teeth induction hardened, no secondary operations can be performed on tooth areas including the bottom land (approx. 1 to 2 mm). 〔Caution on Product Characteristics〕[Caution on Secondary Operations]

① Regarding SRTB ratchets with hubs, please note the direction of teeth, viewed from the hub side. KHK can produce ratchets that have teeth pointed in the opposite direction as a custom order item.

① The pawls are designed to prevent reverse rotation. They are not suitable for use as driving ratchets or driving rotation.

② SRT2/3-C is manufactured using a lost wax casting method.

〔Caution on Product Characteristics〕

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Ratchets

A B DI

J

H

E FG

T9

Allowable torque (N・m) Allowable torque (kgf・m) Weight

（kg）Catalog No.

Bending strength Bending strength

3.074.10 6.00 7.118.24

0.310.420.610.730.84

0.0350.0530.0960.120.15

SRT2/3-50SRT2/3-60SRT2/3-80SRT2/3-90SRT2/3-100

14.7 19.5 29.4 34.5 39.4

1.501.993.003.524.02

0.160.240.440.560.70

SRT1-50SRT1-60SRT1-80SRT1-90SRT1-100

29.0 49.2 70.8 94.3

2.965.027.229.61

0.280.530.851.24

SRT2-30SRT2-40SRT2-50SRT2-60

92.6 158 229

9.4416.123.3

0.861.582.54


226 385 559

23.039.357.0

1.893.535.66


3.07 4.10 6.00 7.11 8.24

0.310.420.610.730.84

0.0670.100.160.210.24

SRTB2/3-50SRTB2/3-60SRTB2/3-80SRTB2/3-90SRTB2/3-100

14.7 19.5 29.4 34.5 39.4

1.501.993.003.524.02

0.240.340.610.730.87

SRTB1-50SRTB1-60SRTB1-80SRTB1-90SRTB1-100

29.0 49.2 70.8 94.3

2.965.027.229.61

0.470.821.141.59

SRTB2-30SRTB2-40SRTB2-50SRTB2-60

92.6 158 229

9.4416.123.3

1.402.173.22


226 385 559

23.039.357.0

2.754.386.72


Pawls

SRT-C

SRT・SRTB

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Gear Couplings GC・GC-I

■ Features


● If you require one set of GC2-30, you will need one GC2-I (outer ring) and two GC2-30 (inner hubs). These components may

also be purchased separately. Therefore, please specify set or each when ordering.

● Inner hubs come with snap rings, S type products have prepared minimum bores and finished products come with set screws.

● Due to the gear teeth being induction hardened, no secondary operations can be performed on tooth areas including the bot-tom land (approx. 1 to 2 mm).

Characteristics of Gear Couplings

● There are many ways to couple shafts to transmit power. We have developed these standardized gear couplings of our own design. They are easier to connect or disconnect than chain couplings.

● The gear teeth of the inner hubs are crowned to allow for up to 5° of shaft angle offset.

● Due to induction hardened gear teeth, these couplings have ex-

cellent durability. All surfaces are plated (Unichromic plating).● The units are machined complete with keyways, set screw

holes and finished bores and are ready for immediate installa-tion. We also offer minimum bore models for users who want to perform their own secondary operations.

Inner hub

Outer ring

Inner hub

Snap Ring Groove

■ Bending Strength of Gear Couplings

Tolerance torques of the gear couplings are determined in accor-

dance with the shear strength of the keys. Allowable shear force of

keys F (N) are calculated from the following formula.

F = b・L・σ・

Additionally, allowable torques (T) of the inner hubs of the gear

coupling, versus shear force of keys, can be calculated from the

formula below.

T =

: Key Width (mm) → Keyway width of inner hubs of the GC Gear Coupling

: Key Length (mm) → Set at –2 mm from the total length of the inner hub

of the GC Gear Coupling

: Allowable Shear Force of keys → Set at 49MPa (5kgf/mm2)

: Safety Factor → Optionally set

: Bore size (mm) → Bore size A of the inner hub of the GC Gear Coupling

Caution: Safety Factor (S) must be set at a value between 1 to 3,

depending on the load types or the coupling displacement.

1s

F・d2000

b

L

σ

s

d

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Gear Couplings

Application

Turning table

CG Inner hubCG Outer ring

Motor

Specific usage for turning the work having no shafts or bores.

Assembly Example: KHK Stock Gears Sample Unit

Module 2 to 2.5

b

L

σ

s

d

GC

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Gear Couplings (Inner hub)GC

Gear Couplings (Outer ring)Module 2～ 2.5

Module 2～ 2.5

GC-I

G

BD C

FEK

AM

L

T2

E

A C D

T1

Specifications

Gear teeth Standard full depth

Pressure angle 20° (Crowing)

Material S45C

Heat treatment Tooth surface induction hardened


Catalog No. Module No. of teeth ShapeBore Hub dia. Pitch dia. Outside dia. Face width Hub width Total length Set Screw

A B H7 C D E F G Size L

GC1-12SGC1-20GC1-22GC1-25

m2 25

T2TKTKTK

12202225

45 50 54 10 25 35

―M5M6M6

―101010

GC2-20SGC2-30GC2-32GC2-35GC2-40

m2 40

T2TKTKTK

2030323540

70 80 84 15 40 55

―M6

M10M10M10

―13131313

GC3-20SGC3-45GC3-50

m2.5 42T2TKTK

204550

90 105 110 20 45 65―

M10M10

―2020

Catalog No. Module No. of teeth ShapeInternal dia. Pitch dia. Outside dia. Face width Backlash

（mm）Weight

（kg）A C D E

GC1-IGC2-IGC3-I

m2m2m2.5

254042

T14676

100

5080

105

68105145

253648

0.40~0.600.331.032.96

① “S” denotes minimum bore products. Inner hubs come with snap rings and set screw.② The allowable torques in the table are obtained from the shear strength of keyways. The shear strength of keyway is assumed to be 49MPa（5kgf/mm2）.① Due to the gear teeth being induction hardened, no secondary operations can be performed on tooth areas including the bottom land (approx. 1 to 2 mm).

〔Caution on Product Characteristics〕

① Due to the gear teeth being induction hardened, no secondary operations can be performed on tooth areas including the bottom land (approx. 1 to 2 mm).

[Caution on Secondary Operations]

[Caution on Secondary Operations]

Specifications


Pressure angle 20°

Material S45C

Heat treatment Tooth surface induction hardened


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Gear Couplings (Inner hub)

Gear Couplings (Outer ring)

G

BD C

FEK

AMJL

TK

C-Shaped Snap Ring Groove Total Width of Gear Coupling Keyway Allowable torque (N・m) Allowable torque (kgf・m) Backlash

（mm）Weight

（kg）Catalog No.

K L M N Width×Depth Bending strength Bending strength

23 1.95 42.5 73

―5 x 2.37 x 37 x 3

―68.7 98.1

137

―7.00

10.0 14.0

0.40~0.60

0.430.370.350.32

GC1-12SGC1-20GC1-22GC1-25

37 2.7 67 115

―7 x 3

10 x 3.310 x 3.310 x 3.3

―245 294 392 490

―25.0 30.040.050.0

0.40~0.60

1.661.481.421.361.23

GC2-20SGC2-30GC2-32GC2-35GC2-40

42 3.2 86.5 135―

12 x 3.312 x 3.3

―785 883

―80.090.0

0.40~0.603.432.742.56

GC3-20SGC3-45GC3-50

N

GC-I

GC

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Involute Spline Shafts & BushingsSV・SVI

■ Features


Characteristics of Gear Couplings

● SV and SVI series are made according to the automotive in-volute spline standard, JIS D 2001: 1959 (FLAT ROOT SIDE FIT, Backlash 0.06 to 0.15)

● Involute spline shafts and bushings are thermal refined to have

good abrasion-resistance.

● Spline bushings may be made in CAC (bronze) type material as a special custom order item.

■ The surface strength of SplineThe design concept of the spline surface strength is the same as that of a key. Here is the formula for the allowable transmission force (N) of spline.

　F ＝ η・z・hw・l・σ

And the formula of allowable torque T (N・m) of spline with re-spect to the surface strength.

　T ＝

In designing a spline shafts, besides considering the surface strength, we should take into account the torsional and bending stresses of the spline.

Here

：Contact ratio of surface → 0.75 (assumed)：Number of teeth → number of teeth (z) of spline from the table：Contact depth of tooth → 1.485：Contact length of spline → Total length (A) of involute spline bushing：Allowable surface stress of spline→19.61MPa (2kgf/mm2) (assumed)：Contact diameter (mm) → Tip diameter of spline shaft D - hw

ηzhw

lσdw

F・dw

2000

● Be sure not to bend shafts or break teeth when perform-ing secondary operations on SV Involute Spline shafts.

● When using SVI Spline Bushings with sliding move-ment, lubrication is necessary on the sliding surface. To prevent scuffing, it is recommended to apply lubricating grease. If used in applications where oil contamination is not desirable, solid lubrication is recommended.

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Involute Spline Shafts & Bushings

Application

SV Involute Spline Shafts are used in shift transmission mechanisms

Slide Bar

SV Involute Spline Shaft

SV Involute Spline Bushing

Assembly Example: KHK Stock Gears Sample Unit

SV

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Involute Spline ShaftsModule 1.667SV

Involute Spline BushingsModule 1.667SVI

d D

GEF’ F

d

TA

E

A D

T1

Specifications

Gear teeth Stub teeth

Pressure angle 20°

Material S45C

Heat treatment Thermal refined

Tooth hardness 225～ 260HB

Specifications

Gear teeth Stub teeth

Pressure angle 20°

Material S45C

Heat treatment Thermal refined

Tooth hardness 225～ 260HB

Catalog No. Module No. of teeth ShapeOutside dia. Shaft dia. Face width Shaft length (R) Shaft length (L) Total length Backlash

（mm）Weight

（kg）D d E F F' G

SV17-170SV20-200SV25-250SV30-300

m1.667

8101316

TA TATBTB

16.6719.6724.6729.67

13152025

135165220270

2020――

15153030

170200250300

0.06~0.150.06~0.150.06~0.150.06~0.15

0.260.430.881.55

Catalog No. Module No. of teeth ShapeInternal dia. Outside dia. Face width Allowable torque (N・m) Allowable torque (kgf・m) Backlash

（mm）Weight

（kg）A D E Surface durability Surface durability

SVI17-40SVI20-45SVI25-55SVI30-65

m1.667

8101316

T1

13.716.721.726.7

40455565

25303845

33.2 59.6

125 222

3.38 6.08

12.8 22.6

0.06~0.150.06~0.150.06~0.150.06~0.15

0.210.310.570.93

① Be sure not to bend shafts or break teeth when performing secondary operations on SV Involute Spline shafts.[Caution on Secondary Operations]

+ 0 . 2 5+ 0 . 1 5

〔Caution on Product Characteristics〕 ① The allowable torques are calculated based on “The surface strength of Spline” . ② It is essential to apply lubricant on contact surface of the spline shaft and the hub. To prevent scuffing,

it is recommended to apply lubricating grease. If used in applications where oil contamination is not desir-able, solid lubrication is recommended.

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Involute Spline Bushings

GE F

Dd

TB

Catalog No. Module No. of teeth ShapeOutside dia. Shaft dia. Face width Shaft length (R) Shaft length (L) Total length Backlash

（mm）Weight

（kg）D d E F F' G

SV17-170SV20-200SV25-250SV30-300

m1.667

8101316

TA TATBTB

16.6719.6724.6729.67

13152025

135165220270

2020――

15153030

170200250300

0.06~0.150.06~0.150.06~0.150.06~0.15

0.260.430.881.55

SVI

Involute Spline Shafts

SV

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Catalog No. Module No. of teeth ShapeBore Hub dia. Pitch dia. Outside dia. Face width Hub width Total length

AH7 B C D E F GQSGA0.4QSGA0.45QSGA0.5QSGA0.55QSGA0.6

0.40.450.50.550.6

10088807266

S5 10 ―

40.039.640.039.639.6

40.840.541.040.740.8

10 ― 10QSGA0.65QSGA0.7QSGA0.75QSGA0.8QSGA0.9QSGA1.0

0.650.70.750.80.91

625854504440

40.340.640.540.039.640.0

41.642.042.041.641.442.0

Catalog No. Module No. of teeth ShapeBore Hub dia. Pitch dia. Outside dia. Face width Hub width Total length

AH7 B C D E F GQSG0.4QSG0.45QSG0.5QSG0.55QSG0.6

0.40.450.50.550.6

10088807266

S0 12.7 22.5

40.039.640.039.639.6

40.840.541.040.740.8

12.7 0.8 14.3QSG0.65QSG0.7QSG0.75QSG0.8QSG0.9QSG1.0

0.650.70.750.80.91

625854504440

40.340.640.540.039.640.0

41.642.042.041.641.442.0

Specifications

Precision grade JIS grade M00 (JIS B 1751)


Pressure angle 20°

Material SK3

Heat treatment Vacuum Hardening

S5

A B C DB

E

G

G

G

G G

G G

S0

Master Gears (Spur Gear)Module 0.4～ 1QSGA・QSG

KHK Matter Gears are high precision gears used in meshing test machines. We proudly provide master gears with technologies ac-quired through our experience in manufacturing standard gears.　＊ These gears are not for power transmission.＊ Mashing Pitch Inspection Data is included for these products.

High Precision Master Gears for meshing test machine.

Available Production

We accept orders even for gears with special specifica-tions, such us Helical Gears. Please feel free to contact us.

■ Module: 0.4 to 1■ Number or Teeth: can be designated as you request.■ Pressure Angles: Adaptable for various sizes, such

as 14.5°, 20° and 22.5°.

Master Gears are available by request

〔Caution on Product Characteristics〕 As custom order products, requires a lead-time for shipping (from the factory) 20 working-days after placing an order. Please allow additional shipping time to get to your local distributor.

〔Caution on Product Characteristics〕 As custom order products, requires a lead-time for shipping (from the factory) 20 working-days after placing an order. Please allow additional shipping time to get to your local distributor.

Other Products: Pawls & Ratchets, Involute Spline Shafts, Spline

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