High Torque Timing Pulleys S8M Type

Brand :

MISUMI

Caution

Please note that the swaged flange options, NFC, RFC, and LFC, are not reflected in the CAD data.
Please check the content on our website as the PDF does not contain the most up-to-date information.

Product Description

[Material]
· Pulley: Extra super duralumin aluminum alloy, S45C equivalent, SUS304
· Flange: Aluminum alloy, SPCC
[Surface treatment]
· Clear anodize, black anodize, hard clear anodize (firm hardness 300HV~), electroless nickel plating, black iron oxide coating

Dimensional Drawing

High Torque Timing Pulleys - S8M: Related Image

Tooth groove dimensions slightly vary according to the number of teeth. (Pitch: 8.0mm)

■S8M

● Pulley Shape

Standard Tooth Profile

Shape A

[ ! ]1

[ ! ]2

Shape B

[ ! ]1

[ ! ]2

[ ! ] For aluminum flanges, the flange thickness is 1.5.
[ ! ] 1 t = 2.0 for 72 toothed pulleys (Machined Flange)
[ ! ] 2 Shaft Bore Specs. H (Round Hole), V or F (Stepped Hole), Y (Both Sides Stepped Hole) and WB (Two-stepped Hole) do not have tapped holes.
[ ! ] The tolerance of the tap position dimension from the boss end face and pulley end face is ±0.3.
[ ! ] For S8M600, select Shape A: W ≤ d × 5 and Shape B: L ≤ d × 5.
[ ! ] Unless otherwise specified except for teeth and F dimensions, the dimension tolerance conforms to JIS B 0405 Class m.
[ ! ] Compatible with S8M type from Mitsuboshi Belting Ltd. as well as Bando Chemical Industries Ltd.

●Shaft Bore Specification Select shaft bore spec mark and each dim. from the table below.
[ ! ] Surface treatment may not be applied to shaft bores.
[ ! ] No standard value is specified for chamfering of d dim.

H Round Hole	P Round Hole + Tap	N New JIS Keyway + Tap C Old JIS Keyway + Tap

	[ ! ] For A-Shape pulley, the screw holes are set at around 120° to keep away from peaks.	[ ! ] Specify NK10 when selecting "New JIS Keywayed Bore" + "Shaft Bore Diameter 10" + "Keyway Width 4.0 mm". [ ! ] The difference between part number N10 and NK10 is the machining dimensions. See the table below, "New JIS Keyway Dimension Tolerance," for details. [ ! ] The position of the keyway and the phase of the teeth are not guaranteed.

V Stepped Hole

F Stepped Hole
(Counterbored Hole on the Hub Side)

Y Both Ends Stepped Hole

WB Two-stepped Hole

[ ! ] Z-V(d) ≥ 2

[ ! ] 3.0 ≤ J ≤ W-3.0
(S8M600 only) 5 ≤ J ≤ W-5.0

[ ! ] Applicable to Shape B only
[ ! ] Z-F(d) ≥ 2

[ ! ] 3.0 ≤ J ≥ L-3.0
(S8M600 only) 5 ≤ J ≤ L-5.0

[ ! ] Applicable to Shape A only
[ ! ] Q-Y(d) ≥ 2
[ ! ] R-Y(d) ≥ 2

[ ! ] S+T ≤ W-3.0
(S8M600 only) S+T ≤ W-5.0

[ ! ] S (T) ≥ 3.0
(S8M600 only) S (T) ≥ 5.0

[ ! ] Applicable to Shape A only
[ ! ] Q-R ≥ 2
[ ! ] R-WB(d) ≥ 2

[ ! ] S+T ≤ W-3.0
(S8M600 only) S+T ≤ W-5.0

[ ! ] S (T) ≥ 3.0
(S8M600 only) S (T) ≥ 5.0

■Belt Nominal Width / Dimensions

mm	Nominal
mm	S8M150	S8M250	S8M300	S8M400	S8M600
A	17	28	33	44	65
W	22	33	38	49	70
L (Number of Teeth: 18 to 43)	37	48	53	64	85
L (Number of Teeth: 44 to 72)	42	53	58	69	90

■Tapped Hole Dimensions (Shaft Bore Specs.: P,N,C)

d_H7 Shaft Bore I.D.	M (Coarse)	Accessory Set Screws	Number of Accessories Included
12	M4	M4 × 3	2
13 to 17	M5	M5 × 4
18 to 30	M6	M6 × 5
31 to 45	M8	M8 × 6
46 to 70	M10	M10 × 8

[ ! ] No specification is set for the tightening torque
of the set screw.

Dimensional tolerances without command

Dimension Range		Tolerance (mm)
Over	or Less	Tolerance (mm)
0.5	3	±0.1
3	6	±0.1
6	30	±0.2
30	120	±0.3

[ ! ] Compliant with JIS B 0405 Class m
(Medium Class).

■Keyway Dimension Table

d Dimensional Tolerance (H7)

Nominal(N,C)	d_H7
8 to 10(K)	＋0.015 0
11 to 18	＋0.018 0
19 to 30	＋0.021 0
31 to 50	＋0.025 0
51 to 70	＋0.030 0

New JIS Keyway Dimension Tolerance

Nominal(N)	b_JS9		t
8 to 10	3	±0.0125	1.4	＋0.1 0
10K to 12	4	±0.0150	1.8
13 to 17	5		2.3
18 to 22	6		2.8
23 to 30	8	±0.0180	3.3	＋0.2 0
31 to 38	10	±0.0180
39 to 44	12	±0.0215
45 to 50	14		3.8
55	16		4.3

Old JIS Keyway Dimension Tolerance

Nominal(C)	b_JS9		t
10 to 12	4	＋0.022 ＋0.010	1.5	＋0.1 0
15 to 20	5		2

■Pulley Shape and Shaft Bore Machining Table

Shape	Hole
Shape	H	P	N(C)	V	F	Y	WB
A	○	○	○	○	‐	○	○
B	○	○	○	○	○	‐	‐

Type	Belt Width					[ M ] Material		[ S ] Surface Treatment	[ A ] Accessory Set Screws
	15 mm	25 mm	30 mm	40 mm	60 mm	Pulley	Flange
	S8M150	S8M250	S8M300	S8M400	S8M600	Pulley	Flange
HTPA	●	●	●	●	●	Extra Super Duralumin Aluminum alloy	Aluminum alloy	Clear Anodize	SUS304
HTPB	●	●	●	●	●			Black Anodize
HTPK	●	●	●	●	●			Hard Clear Anodize
HTPN	●	●	●	●	●			Electroless nickel plating
HTPT	●	●	●	●	●	S45C Equivalent	SPCC	-	SCM435 (Black Oxide)
HTPM	●	●	●	●	●			Black Oxide Coating
HTPP	●	●	●	●	●			Electroless nickel plating
HTPS	●	●	●	-	-	SUS304	SUS304	-	SUS304

[ ! ] Flange is already swaged, and set screws are included for Shaft Bores P, N and C.
[ ! ] Due to vibrations during transportation, the set screw may become detached from the main body.
[ ! ] For orders with no flange, please specify the alteration NFC.