Spur Gear, Pressure Angle 20°, Module 2.5

A gear is a product with teeth added around the circumference of a drive wheel. Gear transmission mechanisms are widely used for transmitting rotational motion, rotational speed, and rotational direction.

Type		Material	Surface Treatment
Round Hole	Keyway
E-GEAHB	E-GEAKB	General structural steel or carbon steel	-
E-GEAHBB	E-GEAKBB		Black Oxide Film

When selecting the shaft hole specification without threads, the fixing screws are not included.
If the gear shape is not specified, the gear shape will be B.
If there are requirements for rust prevention, give priority to products with hard chrome plating, electroless nickel plating surface treatment, or stainless steel SUS3 series materials.

  

■ Intended Use for Spur Gears

Type of Transmission	Description	Transmission Diagram (Simple)	Representative Transmission Methods	Representative Types of Transmission Pairings
Parallel Transmission	Parallel transmission of rotation/power between two axes with meshing gears			Spur Gear + Spur Gear Helical Gear + Helical Gear Herringbone Gear + Herringbone Gear Spur Gear + Internal Gear Helical Gear + Internal Helical Gear
Linear Transmission	Rotational displacement/power transmitted linearly, or linear displacement/power transmitted rotationally			Spur Gear + Spur Rack Helical Gear + Helical Rack

  

Part Number		Number of Teeth	B	Gear Shape	Shaft Hole Diameter PH8 Specified Unit: 1 mm		d Reference Circle Diameter	D Tip Circle Diameter	G Root Circle Diameter	H	L	ℓ1	ℓ2	M (Coarse Thread)	*1 Allowable Transmission Force (N⋅m) Bending Strength
Type	Module				Round Hole Round Hole+Threaded Hole	Keyway Hole Keyway Hole + Threaded Hole									General structural steel or carbon steel
	2.5	12	25	A B	8 to 13	8N	30	35	23.75	23	37	12	6	M5	38.58
		14			8 to 15	8N to 12N	35	40	28.75	25	41	16	8		49.96
		15			8 to 20	8N to 15N	37.5	42.5	31.25	30					55.96
Round E-GEAHB E-GEAHBB Round Hole+Threaded Hole (Type B) E-GEAB E-GEABB Keyway Hole E-GEAKB E-GEAKBB		16			8 to 22	8N to 17N	40	45	33.75	32					61.98
		17			8 to 24	8N to 19N	42.5	47.5	36.25	35					68.13
		18			8 to 26	8N to 22N	45	50	38.75	38					74.36
		19			8 to 27		47.5	52.5	41.25	39					80.60
		20			8 to 28	8N to 23N	50	55	43.75	40					87.09
		21			8 to 29	8N to 25N	52.5	57.5	46.25	42					93.50
		22			8 to 32	8N to 29N	55	60	48.75	44					100.13
		23			8 to 32	8N to 28N	57.5	62.5	51.25	46					106.58
		24			8 to 36	8N to 32N	60	65	53.75	48					113.19
		25			8 to 38	8N to 33N	62.5	67.5	56.25	50				M6	119.98
		26			8 to 43	8N to 37N	65	70	58.75	55					126.94
		27			8 to 48	8N to 40N	67.5	72.5	61.25	60					133.57
		28					70	75	63.75						140.86
		29			8 to 43	8N to 39N	72.5	77.5	66.25	62					147.18
		30			8 to 51	8N to 43N	75	80	68.75	65					154.16
		32			8 to 55	8N to 47N	80	85	73.75	70					167.17
		34			10 to 55	10N to 47N	85	90	78.75						182.65
		35					87.5	92.5	81.25						189.48
		36			10 to 57	10N to 49N	90	95	83.75	75					195.56
		38					95	100	88.75						210.35
		40			10 to 60	10N to 50N	100	105	93.75	80					223.66
		42					105	110	98.75						238.12
		44					110	115	103.75						252.85
		45					112.5	117.5	106.25						260.32
		46					115	120	108.75						267.86
		48			10 to 60		120	125	113.75	85					281.94
		50			12 to 60	12N to 50N	125	130	118.75						296.17
		52			15 to 60	15N to 50N	130	135	123.75						310.53
		54					135	140	128.75						325.04
		55					137.5	142.5	131.25						333.08
		56					140	145	133.75						341.19
		58					145	150	138.75						354.50
		60			25 to 60	25N to 50N	150	155	143.75						369.44
		62					155	160	148.75						382.84
		64					160	165	153.75						398.01
		65					162.5	167.5	156.25						404.75
		68					170	175	163.75						428.78
		70					175	180	168.75						442.41
		72					180	185	173.75						456.04
		75					187.5	192.5	181.25						478.65
		80					200	205	193.75						396.36

When selecting a shaft hole diameter of 10 with keyway hole + threaded hole and a keyway width of 4.0 mm (height 1.8 mm), please specify the P dimension as 10K. For details, please refer to Keyway Specifications
*1 The allowable transmission force in the table is a reference value calculated under normal conditions. For details, please refer to Gear Transmission Power Calculation
When using keyway holes + threaded holes, the shaft hole diameter 9N specification cannot be manufactured.

Type			Material	Surface Treatment
Round Hole	Round Hole+Threaded Hole	Keyway Hole Keyway Hole + Threaded Hole
E-GEAHB	E-GEAB	E-GEAKB	General structural steel or carbon steel	-
E-GEAHBB	E-GEABB	E-GEAKBB		Ferroferric Oxide Protective Film

If there are requirements for rust prevention, give priority to products with surface treatment of electroless nickel plating or those made of austenitic stainless steel.