Timing Pulleys - XL Type

MISUMI

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.

[Material]
· Pulley: Aluminum alloy, S45C equivalent, SUS304
· Flange: Aluminum alloy, SPCC, SUS304
[Surface treatment]
· Clear anodize, black anodize, hard clear anodize (firm hardness 300HV~), electroless nickel plating, black iron oxide coating
[Related Products]
· Timing belt Timing Belt, Long Timing Belts-Iron Rubber, Open End Belt Iron Rubber, Open End Belts/Polyurethane/Chloroprene Rubber
· Idler Idler with Teeth Center Bearing, Idler with Teeth Both Sides Bearing, Idler - Backside Tensioning Center Bearing, Idler - Backside Tensioning Both Sides Bearing

Dimensional Drawing

■XL

● Pulley Shape

Tooth Profile
(ISO Standard Rack Dimensions)

Shape A

Shape B

[ ! ]

Tooth groove dimensions slightly vary according to the number of teeth. (Pitch: 5.08 mm)

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).

[ ! ] For aluminum and stainless steel flanges, the flange thickness is 1.5.
[ ! ] The tolerance of the tap position dimension from the boss end face and pulley end face is ±0.3.
[ ! ] 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.
[ ! ] Unless otherwise specified except for teeth and F dimensions, the dimension tolerance conforms to JIS B 0405 Class m.

● 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
[ ! ] 2.0 ≤ J ≤ W-2.0

[ ! ] Applicable to Shape B only
[ ! ] Z-F(d) ≥ 2
[ ! ] 2.0 ≤ J ≤ L-2.0

[ ! ] Applicable to Shape A only
[ ! ] Q-Y(d) ≥ 2
[ ! ] R-Y(d) ≥ 2
[ ! ] S+T ≤ W-3.0
[ ! ] S (T) ≥ 3.0

[ ! ] Applicable to Shape A only
[ ! ] Q-R ≥ 2
[ ! ] R-WB(d) ≥ 2
[ ! ] S+T ≤ W-3.0
[ ! ] S (T) ≥ 3.0

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

d_H7 Shaft Bore I.D.	M (Coarse)	Accessory Set Screws	Number of Accessories Included
4	M3	M3 × 3	2
5 to 12	M4	M4 × 3
13 to 17	M5	M5 × 4
18 to 35	M6	M6 × 5

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

■Belt Nominal Width / Dimensions

mm	Nominal
mm	XL025	XL031	XL037	XL050
A	7.5	9.0	11.0	14.0
W	12.5	14.0	16.0	19.0
L	21.0	23.0	25.0	28.0

■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

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	±0.0215	3.8

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
	6.4 mm (1/4 in)	7.9 mm (5/16 in)	9.5 mm (3/8 in)	12.7 mm (1/2 in)	Pulley	Flange
	XL025	XL031	XL037	XL050	Pulley	Flange
ATP	●	●	●	●	Aluminum alloy	Aluminum alloy	Clear Anodize	SUS304
BTP	●	●	●	●			Black Anodize
KTP	●	●	●	●			Hard Clear Anodize
NTP	●	●	●	●			Electroless nickel plating
MTP	●	-	●	●	S45C Equivalent	SPCC	-	SCM435 (Black Oxide)
MTPB	●	-	●	●			Black Oxide Coating
MTPP	●	-	●	●			Electroless nickel plating
STP	●	●	●	●	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.