{"id":559,"date":"2026-05-27T03:34:39","date_gmt":"2026-05-27T03:34:39","guid":{"rendered":"https:\/\/planetary-gearboxes.com\/?post_type=product&p=559"},"modified":"2026-05-27T03:34:39","modified_gmt":"2026-05-27T03:34:39","slug":"ep-baf-high-rigidity-planetary-gearbox","status":"publish","type":"product","link":"https:\/\/planetary-gearboxes.com\/ar\/product\/ep-baf-high-rigidity-planetary-gearbox\/","title":{"rendered":"\u0639\u0644\u0628\u0629 \u062a\u0631\u0648\u0633 \u0643\u0648\u0643\u0628\u064a\u0629 \u0639\u0627\u0644\u064a\u0629 \u0627\u0644\u062f\u0642\u0629 \u0645\u0646 \u0633\u0644\u0633\u0644\u0629 EP-BAF - \u0639\u0645\u0648\u062f \u0625\u062e\u0631\u0627\u062c \u0639\u0627\u0644\u064a \u0627\u0644\u0635\u0644\u0627\u0628\u0629 (\u0645\u0646 EP-BAF042 \u0625\u0644\u0649 EP-BAF220)"},"content":{"rendered":"

<\/main><\/p>\n
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EP-BAF Series \u2014 High-Rigidity Output Shaft Precision Planetary Gearbox<\/h2>\n
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\"EP-BAF<\/p>\n

\n
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High-Rigidity
\nOutput Shaft<\/div>\n
Enlarged shaft diameter<\/div>\n<\/div>\n
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\u22643′<\/div>\n
\u0631\u062f \u0641\u0639\u0644 \u0639\u0646\u064a\u0641 (\u0623\u0631\u0643\u0645\u064a\u0646)<\/div>\n<\/div>\n
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2,000<\/div>\n
Max Torque (N\u00b7m)<\/div>\n<\/div>\n
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\u226595%<\/div>\n
\u0643\u0641\u0627\u0621\u0629<\/div>\n<\/div>\n<\/div>\n

\n\u2190 Browse All Planetary Gearbox Series
\n<\/a><\/div>\n<\/div>\n
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\u0627\u0644 EP-BAF series high-precision planetary gearbox<\/strong> addresses a specific structural problem that the standard EP-BAB series is not designed for: applications where a gear, timing pulley, sprocket, cam, or eccentric is mounted directly onto the output shaft end, imposing a concentrated radial force and bending moment on the shaft itself<\/strong> \u2014 not on the flange face. This high-precision planetary gearbox achieves this through an output shaft with a larger diameter than the equivalent EP-BAB frame, increasing the shaft’s second moment of area and its resistance to bending deflection under combined torsional and radial loading.<\/p>\n

Seven frame sizes from EP-BAF042 through EP-BAF220 cover rated output torque up to 2,000 N\u00b7m. The same P1 backlash of \u22643 arcmin single-stage<\/strong> and \u226595% single-stage efficiency as the EP-BAB series are maintained \u2014 the high-rigidity shaft design adds radial load capacity without sacrificing the precision or efficiency that define Korea Ever-Power’s standard precision family. Published moment of inertia data<\/strong> supports servo inertia-ratio verification at the design stage.<\/p>\n

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\ud83d\udd29 Enlarged Output Shaft<\/div>\n
Larger diameter vs EP-BAB \u2014 higher radial load and bending resistance.<\/div>\n<\/div>\n
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\ud83d\udcd0 Inertia Data Published<\/div>\n
J values for all 7 frames for servo sizing before hardware delivery.<\/div>\n<\/div>\n
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\ud83c\udfaf \u22643 Arcmin P1<\/div>\n
Full precision maintained despite the reinforced shaft geometry.<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/section>\n

<\/p>\n

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Output Shaft Rigidity \u2014 Why It Matters and When EP-BAF is the Right Choice<\/h2>\n
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<\/p>\n

\n
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EP-BAB (standard shaft)
\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510
\n\u2502 Gearbox \u2502\u2500\u2500\u2500\u2500\u2500\u2500 shaft \u2500\u2500\u25cf \u2190 Fr (radial)
\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518 \u2502
\n\u2193 deflection \u03b4\u2081EP-BAF (high-rigidity shaft)
\n\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510
\n\u2502 Gearbox \u2502\u2550\u2550\u2550\u2550\u2550\u2550\u2550 shaft \u2550\u2550\u25cf \u2190 Fr
\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518 \u2502
\n\u2193 deflection \u03b4\u2082 << \u03b4\u2081Shaft rigidity (EI\/L\u00b3) \u221d d\u2074
\nDoubling diameter \u2192 16\u00d7 stiffer<\/div>\n

Bending stiffness scales with the fourth power of shaft diameter<\/p>\n<\/div>\n<\/div>\n

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The Shaft Loading Problem Standard Gearboxes Don’t Solve<\/h3>\n

In a standard servo gear reducer installation, the output shaft connects to the load via a coupling or a flange-mounted rotary table \u2014 and the shaft itself carries only torsion. Radial forces from the load are supported by separate bearings in the machine structure. In this configuration, EP-BAB’s standard shaft diameter is adequate.<\/p>\n

The problem arises when a gear, timing pulley, or sprocket is mounted directly on the gearbox output shaft<\/strong> without a separate bearing support between the gear and the gearbox housing. In this case, the mesh force from the driven gear \u2014 which is purely radial \u2014 acts as a cantilever bending load on the output shaft at the distance from the gearbox face to the gear mesh point. This bending load causes shaft deflection and, at the gearbox output bearing, generates a reaction radial force that the output bearing must sustain on top of its normal operating load.<\/p>\n

EP-BAF’s larger-diameter output shaft responds to exactly this scenario. The shaft bending stiffness (EI) scales with the fourth power of shaft diameter \u2014 a modest increase in shaft diameter produces a disproportionate increase in radial load capacity and a corresponding reduction in shaft deflection. The output bearing reaction force is reduced, bearing L10 life is extended, and the radial shaft deflection that would otherwise manifest as gear mesh quality degradation or positioning drift is suppressed.<\/p>\n<\/div>\n<\/div>\n

<\/p>\n

EP-BAF vs EP-BAB \u2014 Choosing Based on Output Shaft Loading<\/h3>\n
\n\n\n\n\n\n\n\n\n\n\n
Loading Condition<\/th>\nEP-BAF \u2605<\/th>\nEP-BAB<\/th>\n<\/tr>\n<\/thead>\n
Output coupled to rotary table or encoder (torsion only)<\/td>\n\u2713 Suitable<\/td>\n\u2713 Preferred (simpler, lower cost)<\/td>\n<\/tr>\n
Gear or sprocket directly on output shaft, no separate bearing<\/td>\n\u2713 Recommended \u2014 high shaft rigidity handles radial mesh force<\/td>\n\u26a0 May exceed shaft radial load rating at high gear mesh forces<\/td>\n<\/tr>\n
Timing pulley or flat belt on shaft, belt tension radial load<\/td>\n\u2713 Recommended \u2014 handles combined torsion + radial belt tension<\/td>\n\u26a0 Check shaft radial load capacity vs belt pre-tension<\/td>\n<\/tr>\n
Cam or eccentric on shaft (inertial and contact radial force)<\/td>\n\u2713 Recommended \u2014 high rigidity resists dynamic radial loading<\/td>\n\u26a0 Dynamic radial load may exceed shaft specification<\/td>\n<\/tr>\n
Flange-mounted rotary table with cantilevered workpiece<\/td>\n\u2713 Suitable<\/td>\n\u2713 Suitable for standard workpiece loads; use EP-BAE for heavy overturning moments<\/td>\n<\/tr>\n
Backlash \/ Efficiency specification<\/td>\n\u22643 arcmin P1 \/ \u226595%<\/td>\n\u22643 arcmin P1 \/ \u226595%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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\u25b8 Important \u2014 small frame rated torque: <\/span>
\nThe enlarged output shaft of EP-BAF042 and EP-BAF060 slightly reduces the rated output torque compared to the same-body-diameter EP-BAB frames. EP-BAF042 at i=4 is rated at 9 N\u00b7m vs 19 N\u00b7m for EP-BAB042; EP-BAF060 at i=5 is rated at 22 N\u00b7m vs 55 N\u00b7m for EP-BAB060. For the larger frames (EP-BAF090 and above), the torque difference is negligible.<\/strong> If your application is in the EP-BAF042 or EP-BAF060 torque range, verify the exact rated torque at your required ratio before finalising the frame selection.<\/span><\/div>\n<\/section>\n

\"BAF \"BAF\u00a0<\/p>\n

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EP-BAF042 to EP-BAF220 \u2014 Complete High-Rigidity Planetary Gearbox Specifications<\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Common Specifications \u2014 All EP-BAF Frames<\/th>\n<\/tr>\n<\/thead>\n
Output Shaft<\/td>\nHigh-rigidity (enlarged diameter vs EP-BAB same-size frame)<\/td>\n<\/tr>\n
Backlash P1 (Precision Grade)<\/td>\nSingle-stage \u22643 arcmin \u00b7 Two-stage \u22645 arcmin<\/td>\n<\/tr>\n
Backlash P2 (Standard Grade)<\/td>\nSingle-stage \u22648 arcmin \u00b7 Two-stage \u226412 arcmin<\/td>\n<\/tr>\n
Single-Stage Ratios<\/td>\n3, 4, 5, 6, 7, 8, 9, 10<\/td>\n<\/tr>\n
Two-Stage Ratios<\/td>\n15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100<\/td>\n<\/tr>\n
\u0643\u0641\u0627\u0621\u0629<\/td>\nSingle-stage \u226595% \u00b7 Two-stage \u226592%<\/td>\n<\/tr>\n
Noise (3,000 rpm, no-load, 1 m)<\/td>\n<65 dB(A)<\/td>\n<\/tr>\n
Peak Torque (Emergency Stop)<\/td>\n3\u00d7 Rated Output Torque (instantaneous)<\/td>\n<\/tr>\n
Max Acceleration Torque<\/td>\n60% of Rated Torque (T\u2082s = 0.6 \u00d7 T\u2082Nor)<\/td>\n<\/tr>\n
\u062f\u0631\u062c\u0629 \u062d\u0631\u0627\u0631\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/td>\n0 \u00b0C to +40 \u00b0C<\/td>\n<\/tr>\n
Output Shaft Type<\/td>\nS1: Smooth \u00b7 S2: With keyway (specify at order)<\/td>\n<\/tr>\n
Backlash Measurement<\/td>\nOutput 100 RPM, force at output shaft centre<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

<\/p>\n

Rated Output Torque (N\u00b7m) \u2014 Single-Stage<\/h3>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n
\u0646\u0633\u0628\u0629<\/th>\nEP-BAF042<\/th>\nEP-BAF060<\/th>\nEP-BAF090<\/th>\nEP-BAF115 \u2020<\/th>\nEP-BAF142<\/th>\nEP-BAF180<\/th>\nEP-BAF220<\/th>\n<\/tr>\n<\/thead>\n
i=3<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n1,140<\/td>\n<\/tr>\n
i=4<\/td>\n9 \u2193 vs BAB<\/span><\/td>\n50<\/td>\n140<\/td>\n\u2014<\/td>\n542<\/td>\n1,050<\/td>\n1,700<\/td>\n<\/tr>\n
i=5<\/td>\n8 \u2193 vs BAB<\/span><\/td>\n22 \u2193 vs BAB<\/span><\/td>\n60<\/td>\n\u2014<\/td>\n160<\/td>\n330<\/td>\n650<\/td>\n<\/tr>\n
i=6<\/td>\n\u2014<\/td>\n20<\/td>\n55<\/td>\n\u2014<\/td>\n150<\/td>\n310<\/td>\n600<\/td>\n<\/tr>\n
i=7<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n\u2014<\/td>\n140<\/td>\n300<\/td>\n550<\/td>\n<\/tr>\n
i=8<\/td>\n\u2014<\/td>\n17<\/td>\n45<\/td>\n\u2014<\/td>\n120<\/td>\n260<\/td>\n500<\/td>\n<\/tr>\n
i=9<\/td>\n\u2014<\/td>\n14<\/td>\n40<\/td>\n\u2014<\/td>\n100<\/td>\n230<\/td>\n450<\/td>\n<\/tr>\n
i=10<\/td>\n\u2014<\/td>\n14<\/td>\n40<\/td>\n\u2014<\/td>\n100<\/td>\n230<\/td>\n450<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u2193 = lower rated torque than equivalent EP-BAB frame due to enlarged shaft geometry. \u2020 EP-BAF115 available \u2014 contact Korea Ever-Power for confirmed torque data.<\/p>\n<\/div>\n

<\/p>\n

Rated Output Torque (N\u00b7m) \u2014 Two-Stage (key ratios)<\/h3>\n
\n\n\n\n\n\n\n\n\n\n\n
\u0646\u0633\u0628\u0629<\/th>\nEP-BAF042<\/th>\nEP-BAF060<\/th>\nEP-BAF090<\/th>\nEP-BAF142<\/th>\nEP-BAF180<\/th>\nEP-BAF220<\/th>\n<\/tr>\n<\/thead>\n
i=25<\/td>\n22<\/td>\n60<\/td>\n160<\/td>\n330<\/td>\n650<\/td>\n2,000<\/td>\n<\/tr>\n
i=30<\/td>\n20<\/td>\n55<\/td>\n150<\/td>\n310<\/td>\n600<\/td>\n1,900<\/td>\n<\/tr>\n
i=35<\/td>\n19<\/td>\n50<\/td>\n140<\/td>\n300<\/td>\n550<\/td>\n1,800<\/td>\n<\/tr>\n
i=50<\/td>\n22<\/td>\n60<\/td>\n160<\/td>\n330<\/td>\n650<\/td>\n2,000<\/td>\n<\/tr>\n
i=90<\/td>\n\u2014<\/td>\n14<\/td>\n40<\/td>\n230<\/td>\n450<\/td>\n1,500<\/td>\n<\/tr>\n
i=100<\/td>\n\u2014<\/td>\n14<\/td>\n40<\/td>\n230<\/td>\n450<\/td>\n1,500<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

<\/p>\n

Published Moment of Inertia \u2014 Single-Stage (kg\u00b7cm\u00b2)<\/h3>\n
\n\n\n\n\n\n
Frame<\/th>\nBAF042<\/th>\nBAF060<\/th>\nBAF090<\/th>\nBAF142<\/th>\nBAF180<\/th>\nBAF220<\/th>\n<\/tr>\n<\/thead>\n
J (kg\u00b7cm\u00b2)
\ni=3~10<\/span><\/td>\n		0.03<\/td>\n0.13\u20130.14<\/td>\n0.44\u20130.48<\/td>\n2.57\u20132.74<\/td>\n7.03\u20137.54<\/td>\n22.51\u201323.67 \/ 50.56\u201354.37<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

Note: EP-BAF220 shows a wider J range than other frames, reflecting the larger variation between low and high ratios at this body size. The upper range (50.56\u201354.37 kg\u00b7cm\u00b2) applies at higher gear ratios with proportionally more planet gear mass contribution.<\/p>\n

<\/p>\n

Maximum Rated Input Speed (RPM) by Frame<\/h3>\n
\n\n\n\n\n\n
Frame<\/th>\n042<\/th>\n060<\/th>\n090<\/th>\n115<\/th>\n142<\/th>\n180<\/th>\n220<\/th>\n<\/tr>\n<\/thead>\n
Max RPM<\/td>\n5,000<\/td>\n5,000<\/td>\n5,000<\/td>\n4,000<\/td>\n4,000<\/td>\n3,000<\/td>\n2,000<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

<\/p>\n

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Model Designation Guide \u2014 EP-BAF Part Number<\/h2>\n
\n
EP-BAF 090 \/ 25 \/ S2 \/ P1 \/ T1<\/div>\n
\n
\n
EP-BAF<\/div>\n
Korea Ever-Power
\nHigh-Rigidity Shaft<\/div>\n<\/div>\n
\n
090<\/div>\n
Housing diameter
\n90 mm<\/div>\n<\/div>\n
\n
25<\/div>\n
Gear ratio
\ni = 25:1<\/div>\n<\/div>\n
\n
S2<\/div>\n
Output shaft
\nwith keyway<\/div>\n<\/div>\n
\n
P1<\/div>\n
Precision grade
\n\u22643 \u062f\u0642\u0627\u0626\u0642 \u0642\u0648\u0633\u064a\u0629<\/div>\n<\/div>\n
\n
T1<\/div>\n
Input flange type
\n(motor-matched)<\/div>\n<\/div>\n<\/div>\n<\/div>\n
\n\n\n\n\n\n\n\n\n\n\n
Position<\/th>\nCode<\/th>\nMeaning<\/th>\n<\/tr>\n<\/thead>\n
\u0645\u0633\u0644\u0633\u0644<\/td>\nEP-BAF<\/td>\nKorea Ever-Power, Korea Ever-Power high-precision planetary gearbox \u2014 standard precision, high-rigidity shaft<\/td>\n<\/tr>\n
Frame Size<\/td>\n042\/060\/090\/115\/142\/180\/220<\/td>\nHousing diameter in mm. Same scale as EP-BAB but different shaft geometry<\/td>\n<\/tr>\n
Gear Ratio<\/td>\n3\u201310 \/ 15\u2013100<\/td>\nSingle-stage: 3,4,5,6,7,8,9,10 \u00b7 Two-stage: 15,20,25,30,35,40,45,50,60,70,80,90,100<\/td>\n<\/tr>\n
Output Shaft<\/td>\nS1 \/ S2<\/td>\nS1: Smooth \u00b7 S2: With keyway \u2014 keyway shaft (S2) is standard for direct gear mounting<\/td>\n<\/tr>\n
Backlash Grade<\/td>\nP1 \/ P2<\/td>\nP1: \u22643’\/\u22645′ (single\/two-stage) \u00b7 P2: \u22648’\/\u226412′<\/td>\n<\/tr>\n
Input Flange<\/td>\nT1 \/ T2<\/td>\nSpecify servo motor model for matched input adapter plate<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>\n

<\/p>\n

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Applications \u2014 Where Direct Shaft Loading Requires High-Rigidity Output<\/h2>\n

\"pls-high-precision-planetary-gearbox-application\"<\/p>\n

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Direct Spur \/ Helical Gear Drive (No Intermediate Bearing)<\/h3>\n

When a spur or helical gear is shrunk-fit or keyed directly onto the gearbox output shaft to drive a mating gear on a parallel shaft, the normal mesh force \u2014 a radial load perpendicular to the pitch line \u2014 acts entirely on the output shaft as a cantilever bending moment. There is no separate bearing between the driven gear and the gearbox housing to relieve this load. EP-BAF’s enlarged shaft diameter resists this bending deflection, maintaining gear mesh alignment and preventing the progressive bearing wear that would result from operating a standard precision planetary gearbox above its shaft radial load limit. Pairs naturally with precision CV drive shafts<\/a> where an intermediate shaft floats between the gearbox gear and the driven load to absorb misalignment.<\/p>\n<\/div>\n

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Timing Belt and Toothed Belt Drives (Pre-Tension Radial Load)<\/h3>\n

Timing belt drives apply a constant radial pre-tension load to the output shaft from the belt span \u2014 in addition to the torque transmission load that changes direction with drive\/coast cycles. The pre-tension is necessary for belt tooth engagement and cannot be reduced without risking belt skip under load reversal. For high-torque timing belt drives \u2014 press feed rolls, shuttle conveyors, screen printing machine axes \u2014 the combined pre-tension and dynamic radial load exceeds the shaft capacity of a standard precision gear reducer. EP-BAF’s reinforced shaft handles this combined loading within its rated radial capacity, extending bearing and shaft fatigue life to match the machine’s service schedule.<\/p>\n<\/div>\n

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Cam and Eccentric Mechanisms (Dynamic Radial Loading)<\/h3>\n

Rotary cam mechanisms for automatic assembly machines, stamping press cam drives, and indexing unit cam followers impose dynamic radial loads on the gearbox output shaft that vary with cam lift profile \u2014 typically pulsing once or twice per revolution. At higher cam speeds, the dynamic radial load amplitude grows with the square of rotational speed. EP-BAF’s high-rigidity shaft and the associated higher-rated output bearing geometry are designed to sustain these pulsating radial loads over the long service life of automated production equipment, where unexpected bearing failure from exceeded shaft radial ratings causes unplanned production downtime.<\/p>\n<\/div>\n<\/div>\n

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Application Reference<\/h3>\n