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SFU [DS] Type

三木プーリのサーボフレックスSFUモデル SFU-DSタイプ金属板ばねカップリング製品画像（高精度トルク伝達・サーボ用途軸継手・産業用カップリング）

This is a leaf spring coupling constructed of steel, featuring a design where the flange—which attaches to the shaft—and the coupling unit can be separated. This not only facilitates high-precision assembly but also allows the drive and driven shafts to be disengaged without moving them during maintenance. It features a flexible double-element design.

SFU-□DS (Key) Type

[Specifications]

Model	Rated Torque [N·m]	Tolerance			Maximum Rotational Speed [min⁻¹]	Torsional spring constant [N·m/rad]	Axial spring constant [N/mm]	Moment of inertia [kg·m²]	Mass [kg]
Model	Rated Torque [N·m]	Eccentricity [mm]	Angular displacement [°]	Axial [mm]	Maximum Rotational Speed [min⁻¹]	Torsional spring constant [N·m/rad]	Axial spring constant [N/mm]	Moment of inertia [kg·m²]	Mass [kg]
SFU-070DS-100N	100	0.25	1 (per side)	±1.0	14,000	120,000	242	0.66×10⁻³	1.04
SFU-080DS-200N	200	0.31	1 (per side)	±1.0	13,000	155,000	273	1.58×10⁻³	1.86
SFU-090DS-300N	300	0.32	1 (per side)	±1.2	12,000	260,000	160.5	2.50×10⁻³	2.29
SFU-100DS-450N	450	0.38	1 (per side)	±1.3	10,000	370,000	270	4.83×10⁻³	3.63
SFU-120DS-600N	600	0.38	1 (per side)	±1.6	8000	485,000	180	10.02×10⁻³	5.09
SFU-140DS-1000N	1000	0.44	1 (per side)	±2.0	7000	700,000	180	22.57×10⁻³	8.27

The maximum rotational speed does not take dynamic balance into account.
The torsional spring constant value refers to the value for a single element.
The moment of inertia and mass are based on the maximum bore diameter.

[Dimensions]

三木プーリのサーボフレックスSFUモデル SFU-DSタイプ金属板ばねカップリング寸法図（高精度トルク伝達・サーボ用途軸継手・産業用カップリング）

Model	d1・d2 [mm]		D [mm]	N [mm]	L [mm]	LM [mm]	LS [mm]	LF[mm]	LP[mm]	S[mm]	F[mm]	d3 [mm]	K[mm]	M1 Quantity - Nominal	M1 Tightening Torque [N·m]
Model	Minimum	Max	D [mm]	N [mm]	L [mm]	LM [mm]	LS [mm]	LF[mm]	LP[mm]	S[mm]	F[mm]	d3 [mm]	K[mm]	M1 Quantity - Nominal	M1 Tightening Torque [N·m]
SFU-070DS-100N	8	25	68	40	83.8	42.6	37.8	23	8	5.9	1	36	38	6-M4	3.4
SFU-080DS-200N	11	35	78	54	100.4	54.2	48.4	26	10	7.7	5	38	42	6-M6	14
SFU-090DS-300N	11	38	88	58	108.6	55.6	48.6	30	10	8.3	2	48	50	6-M6	14
SFU-100DS-450N	16	42	98	68	128.4	65.4	58.4	35	12	10.2	0	50	56	6-M8	34
SFU-120DS-600N	19	50	118	78	134.4	65.4	58.4	38	12	10.2	1	66	68	6-M8	34
SFU-140DS-1000N	22	60	138	88	157.2	74.2	67.2	45	15	10.6	8	76	78	6-M8	34

The designation for an M1 bolt consists of the quantity followed by the thread size, where the quantity refers to the number of flanges on one side.

[Standard Hole Diameter]

Model	Nominal	Standard Hole Diameter d1・d2 [mm]
Model	Nominal	8	9	10	11	12	14	15	16	17	18	19	20	22	24	25	28	30	32	35	38	40	42	45	48	50	55	56	60
SFU-070DS-□-□-100N	d1	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-070DS-□-□-100N	d2	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-080DS-□-□-200N	d1				●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-080DS-□-□-200N	d2				●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-090DS-□-□-300N	d1				●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-090DS-□-□-300N	d2				●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-100DS-□-□-450N	d1								●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-100DS-□-□-450N	d2								●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-120DS-□-□-600N	d1											●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-120DS-□-□-600N	d2											●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-140DS-□-□-1000N	d1													●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●
SFU-140DS-□-□-1000N	d2													●	●	●	●	●	●	●	●	●	●	●	●	●	●	●	●

The hole diameters indicated by the ● symbol are standard hole diameters. For details, please refer to the standard hole machining specifications.

三木プーリのサーボフレックスシリーズSFUモデル DSタイプ金属板ばねカップリングご注文時の型式構成説明図

[Standard Hole Machining Specifications]

Keyway Dimensions Table

Unit [mm]

Compatible with Old JIS (Type 2) Standards					Compliant with New JIS (H9) Standard					Compliant with New JIS (JS 9) Standard					Compliant with New JIS (P9) Standard
Nominal hole diameter	Hole diameter (d1, d2)	Keyway width (W1, W2)	Keyway depth (T1, T2)	Set screw hole (M)	Nominal hole diameter	Hole diameter (d1, d2)	Keyway width (W1, W2)	Keyway depth (T1, T2)	Set screw hole (M)	Nominal hole diameter	Hole diameter (d1, d2)	Keyway width (W1, W2)	Keyway depth (T1, T2)	Set screw hole (M)	Nominal hole diameter
Nominal hole diameter	H7, H8	E9	+0.3 0	－	Nominal hole diameter	H7, H8	H9	+0.3 0	－	Nominal hole diameter	H7, H8	JS9	+0.3 0	－	Nominal hole diameter
8	8 +0.0220	－	－	2–M4	8H	8 + 0.0220	3 + 0.0250	9.4	2-M4	8J	8+0.0220	3±0.0125	9.4	2-M4	8P
9	9 + 0.0220	－	－	2-M4	9H	9 + 0.0220	3 + 0.0250	10.4	2-M4	9J	9 + 0.0220	3±0.0125	10.4	2-M4	9P
10	10 + 0.0220	－	－	2-M4	10H	10 + 0.0220	3 + 0.0250	11.4	2-M4	10J	10 + 0.0220	3±0.0125	11.4	2-M4	10P
11	11 + 0.0180	－	－	2-M4	11H	11 + 0.0180	4 + 0.0300	12.8	2-M4	11J	11+0.0180	4±0.0150	12.8	2-M4	11P
12	12+0.0180	4 + 0.050 + 0.020	13.5	2–M4	12H	12 + 0.0180	4 + 0.0300	13.8	2-M4	12J	12+0.0180	4±0.0150	13.8	2-M4	12P
14	14+0.0180	5 + 0.050 + 0.020	16.0	2–M4	14H	14 + 0.0180	5 + 0.0300	16.3	2-M4	14J	14+0.0180	5±0.0150	16.3	2-M4	14P
15	15 + 0.0180	5 + 0.050 + 0.020	17.0	2-M4	15H	15 + 0.0180	5 + 0.0300	17.3	2-M4	15J	15+0.0180	5±0.0150	17.3	2-M4	15P
16	16+0.0180	5 + 0.050 + 0.020	18.0	2–M4	16H	16 + 0.0180	5 + 0.0300	18.3	2-M4	16J	16+0.0180	5±0.0150	18.3	2-M4	16P
17	17 + 0.0180	5 + 0.050 + 0.020	19.0	2–M4	17H	17+0.0180	5 + 0.0300	19.3	2-M4	17J	17+0.0180	5±0.0150	19.3	2-M4	17P
18	18 + 0.0180	5 + 0.050 + 0.020	20.0	2-M4	18H	18 + 0.0180	6 + 0.0300	20.8	2-M5	18J	18 + 0.0180	6±0.0150	20.8	2-M5	18P
19	19 + 0.0210	5 + 0.050 + 0.020	21.0	2–M4	19H	19 + 0.0210	6 + 0.0300	21.8	2-M5	19J	19 + 0.0210	6±0.0150	21.8	2-M5	19P
20	20 + 0.0210	5 + 0.050 + 0.020	22.0	2–M4	20H	20 + 0.0210	6 + 0.0300	22.8	2-M5	20J	20 + 0.0210	6±0.0150	22.8	2-M5	20P
22	22+0.0210	7 + 0.061 + 0.025	25.0	2–M6	22H	22 + 0.0210	6 + 0.0300	24.8	2-M5	22J	22 + 0.0210	6±0.0150	24.8	2-M5	22P
24	24 + 0.0210	7 + 0.061 + 0.025	27.0	2–M6	24H	24 + 0.0210	8 + 0.0360	27.3	2-M6	24J	24+0.0210	8±0.0180	27.3	2-M6	24P
25	25 + 0.0210	7 + 0.061 + 0.025	28.0	2–M6	25H	25 + 0.0210	8 + 0.0360	28.3	2-M6	25J	25+0.0210	8±0.0180	28.3	2-M6	25P
28	28.0210	7 + 0.061 + 0.025	31.0	2–M6	28H	28 + 0.0210	8 + 0.0360	31.3	2-M6	28J	28+0.0210	8±0.0180	31.3	2-M6	28P
30	30 + 0.0210	7 + 0.061 + 0.025	33.0	2–M6	30H	30 + 0.0210	8 + 0.0360	33.3	2–M6	30J	30+0.0210	8±0.0180	33.3	2-M6	30P
32	32+0.0250	10 + 0.061 + 0.025	35.5	2–M8	32H	32 + 0.0250	10 + 0.0360	35.3	2-M8	32J	32 + 0.0250	10±0.0180	35.3	2-M8	32P
35	35.00000000000000000000000000000000000000000000000000000000000000	10 + 0.061 + 0.025	38.5	2–M8	35H	35 + 0.0250	10 + 0.0360	38.3	2-M8	35J	35+0.0250	10±0.0180	38.3	2-M8	35P
38	38.00000000000000000000000000000000000000000000000000000000000000	10 + 0.061 + 0.025	41.5	2-M8	38H	38 + 0.0250	10 + 0.0360	41.3	2-M8	38J	38+0.0250	10±0.0180	41.3	2-M8	38P
40	40+0.0250	10 + 0.061 + 0.025	43.5	2–M8	40H	40 + 0.0250	12 + 0.0430	43.3	2-M8	40J	40 + 0.0250	12±0.0215	43.3	2-M8	40P
42	42 + 0.0250	12 + 0.075 + 0.032	45.5	2–M8	42H	42 + 0.0250	12 + 0.0430	45.3	2-M8	42J	42 + 0.0250	12±0.0215	45.3	2-M8	42P
45	45.0250	12 + 0.075 + 0.032	48.5	2–M8	45H	45 + 0.0250	14 + 0.0430	48.8	2-M10	45J	45+0.0250	14±0.0215	48.8	2-M10	45P
48	48 + 0.0250	12 + 0.075 + 0.032	51.5	2–M8	48H	48 + 0.0250	14 + 0.0430	51.8	2-M10	48J	48 + 0.0250	14±0.0215	51.8	2-M10	48P
50	50 + 0.0250	12 + 0.075 + 0.032	53.5	2–M8	50H	50 + 0.0250	14 + 0.0430	53.8	2–M10	50J	50 + 0.0250	14±0.0215	53.8	2-M10	50P
55	55+0.0300	15 + 0.075 + 0.032	60.0	2–M10	55H	55 + 0.0300	16 + 0.0430	59.3	2-M10	55J	55+0.0300	16±0.0215	59.3	2-M10	55P
56	56+0.0300	15 + 0.075 + 0.032	61.0	2–M10	56H	56 + 0.0300	16 + 0.0430	60.3	2-M10	56J	56+0.0300	16±0.0215	60.3	2-M10	56P
60	60 + 0.0300	15 + 0.075 + 0.032	65.0	2–M10	60H	60 + 0.0300	18 + 0.0430	64.4	2-M10	60J	60+0.0300	18±0.0215	64.4	2-M10	60P

Unit [mm]

Compatible with new standard motors
Nominal Bore Diameter	Bore Diameter (d1, d2)	Keyway width (W1, W2)	Keyway depth (T1, T2)	Set screw hole (M)
Nominal Bore Diameter	G7, F7	H9	+0.3 0	－
14N	14+0.024+0.006	5 + 0.0300	16.3	2–M4
19N	19 + 0.028 + 0.007	6 + 0.0300	21.8	2-M5
24N	24 + 0.028 + 0.007	8 + 0.0360	27.3	2-M6
28N	28 + 0.028 + 0.007	8 + 0.0360	31.3	2-M6
38N	38 + 0.050 + 0.025	10 + 0.0360	41.3	2-M8
42N	42 + 0.050 + 0.025	12 + 0.0430	45.3	2-M8
48N	48 + 0.050 + 0.025	14 + 0.0430	51.8	2-M10
55N	55 + 0.060 + 0.030	16 + 0.0430	59.3	2–M10
60N	60 + 0.060 + 0.030	18 + 0.0430	64.4	2-M10

[Location of the set screw]

Model	Distance from the end face of the set screw [mm]
SFU-070	7
SFU-080	8
SFU-090	9
SFU-100	12
SFU-120	12
SFU-140	15

The set screw and keyway are not located on the same plane. *The set screw is included with the product.
The positional accuracy of keyway machining is determined by visual inspection. *Please contact us if you require specific positional accuracy for each keyway relative to the hub.