Specs/CAD

mm inch

Part Number	Max. Bore Diameter (mm)	Keyway Additional Modification Max. Bore Diameter (mm)	Rated Torque＊1 (N・m)Rated Torque＊1 (lbf in.)	Max. Rotational Frequency (min-1)	Moment of Inertia (kg・m2)＊2Moment of Inertia (oz. in.2)＊2	Static Torsional Stiffness (N･m/rad)Static Torsional Stiffness (lbf in./deg)	Max. Lateral Misalignment (mm)Max. Lateral Misalignment (in.)	Max. Angular Misalignment (°)	Max. Axial Misalignment (mm)Max. Axial Misalignment (in.)	Mass (g) ＊2Mass (oz) ＊2
XGS2-15C	6	-	0.54.43	42000	2.1×10-70.011	649.89	0.150.006	1.5	±0.2±0.008	70.25
XGS2-19C	8	6	0.87.08	33000	5.9×10-70.032	17026.26	0.150.006	1.5	±0.2±0.008	120.42
XGS2-25C	12	9	2.320.35	25000	2.4×10-60.131	29044.79	0.150.006	1.5	±0.2±0.008	240.85
XGS2-27C	14	10	2.320.35	23000	3.2×10-60.175	29044.79	0.150.006	1.5	±0.2±0.008	280.99
XGS2-30C	15	11	3.329.21	21000	5.2×10-60.284	43066.42	0.20.008	1.5	±0.3±0.012	381.34
XGS2-34C	16	12	5.548.68	18000	1.1×10-50.601	800123.57	0.20.008	1.5	±0.3±0.012	612.15
XGS2-39C	20	15	761.95	16000	2.1×10-51.148	930143.65	0.20.008	1.5	±0.3±0.012	903.17

＊1：　Correction of rated torque due to load fluctuation is not required. If ambient temperature exceeds 30°C, be sure to correct the rated torque with temperature correction factor shown in the following table.

The allowable operating temperature of XGS2 is -10℃ to 120℃.

※ The shaft's slip torque may be smaller than the coupling's rated torque depending on the shaft bore. XGT2XGL2

＊2：　These are values with max. bore diameter.

Part Number	Standard Bore Diameter D1･D2
XGS2-15C	3-5	3-6	4-4	4-5	4-6
	4.5-5	5-5	5-6	6-6
XGS2-19C	4-5	5-5	5-6	5-7	5-8
	6-6	6-6.35	6-7	6-8	6.35-8
	8-8
XGS2-25C	5-6	5-8	6-6	6-8	6-10
	6-11	6-12	6.35-8	6.35-10	8-8
	8-10	8-11	8-12	10-10	10-12
	12-12
XGS2-27C	5-6	5-8	5-14	6-6	6-8
	6-10	6-11	6-12	6-14	8-8
	8-10	8-11	8-12	8-14	10-10
	10-12	10-14	12-12	12-14	14-14
XGS2-30C	8-8	8-10	8-11	8-12	8-14
	8-15	10-10	10-11	10-12	10-14
	10-15	11-12	12-12	12-14	12-15
	14-14	14-15	15-15
XGS2-34C	8-8	8-10	8-11	8-12	8-14
	8-15	10-10	10-11	10-12	10-14
	10-15	11-11	11-12	12-12	12-14
	12-15	14-14	14-15	15-15	16-16
XGS2-39C	10-10	10-12	10-14	10-15	10-16
	12-12	12-14	12-15	12-16	12-19
	12-20	14-14	14-15	14-16	15-15
	15-16	15-19	16-16	17-17	20-20

● All products are provided with hex socket head cap screw.
● Recommended tolerance for shaft diameters is h6 and h7.
● In case of mounting on D-cut shaft, be careful about the position of the D-cut surface of the shaft. ⇒Mounting and Maintenance
● Bore and keyway modifications are available on request. Please take advantage of our modification services.

Ambient Temperature / Temperature Correction Factor

Slip torque

As in the table below, the clamping types XGT2-C, XGL2-C, and XGS2-C have different slip torque according to the bore diameter. Take care during selection.

Structure

Clamping Type

XGT2-C Standard type XGT2
XGL2-C Long type XGL2
XGS2-C Short typeXGS2

Internal Structure

Material/Finish

Characteristics

• Recommended Applicable Motor

• Property

• High-gain flexible coupling which surpasses XGT-CXGL-CXGS-C in performance. This is a single-piece construction with the two aluminum hubs molded with high-gain rubber.
• The optimal damping and rigidity design enables realization of even greater servomotor gain, leading to reduced stabilization time.
• Technical information⇒Productivity and stabilization time
• Suppressing speed unevenness control during stepping motor operation is effective.⇒Suppressing speed unevenness during stepping motor operation
• Contributes to improved productivity and quality by suppressing residual vibration during positioning.
• O.D. φ15-φ56 types use high-gain fluoro-resin rubber. Heat resistance, oil resistance, and chemical resistance are excellent.⇒Physical properties and chemical resistance of high-gain type rubber
• Standard type XGT2-C / long type XGL2-C / short type XGS2-C are now standardized.

Application

Semiconductor manufacturing equipment / Mount machines / Machine tools / Packaging machines

Selection

Selection Based on Shaft Diameter and Rated Torque

The area bounded by the shaft diameter and rated torque indicates the selection size.

Selection Example

In case of selected parameters of shaft diameter of φ16 and load torque of 7N・m, the selected size is XGT2-34C.

Selection Based on the Rated Output of the Servomotor

Eccentric Reaction Force

This is the force generated when placing XGT2-CXGL2-CXGS2-C in an eccentric condition.
As the eccentric reaction force becomes smaller, the force acting on the shaft bearing also becomes smaller.

Thrust reaction force

This is the force generated when compressing XGT2-CXGL2-CXGS2-C in the axial direction. As the thrust reaction force becomes smaller, the force acting on the motor also becomes smaller.

Productivity and Stabilization Time

In a production facility which uses servomotors, single-axis actuators and ball screws, the key to improved productivity is operating these components accurately, as directed by a program. However, occasionally the command execution may be delayed.
For example, when trying to stop the actuator at a predetermined position, sometimes it will stop later than the command, which we refer to as a delay in stabilization time. Since the operation does not shift to the next process until the actuator completely stops, it is important to shorten stabilization time and thereby improve productivity.

Gain and Stabilization Time of Servomotor

This shows how the servomotor gain movement follows the command.
Increasing the gain helps to reduce stabilization time, but increasing it too far causes hunting, making servomotor control impossible.
Increasing the gain while suppressing hunting requires fine adjustment of the servomotor parameters.
However, when a servomotor is combined with a coupling with a metal disk type in the elastic segment, raising the gain tends to cause hunting, making it difficult to resolve the problem by fine adjustments to parameters.
When hunting occurs, it is generally recommended to change to a coupling with higher rigidity to increase the rigidity of the rotating system.
However, in reality, it is not possible to increase the rigidity of the entire rotating system including the ball screw simply by changing the coupling; so changing to a highly rigid coupling such as a disk-type may not be effective.

Suppressing speed unevenness during stepping motor operation

Test Devices

Motor: α step AR66AK-1 Manufactured by Oriental Motor Co., Ltd.

Set voltage----24 VDC

Resolution----1000 p/r

Moment of inertia----1250×10-7kg・cm2

Encoder: RD5000 Manufactured by Nikon Corporation

Drive Parameters

Startup speed: 60 min-1

Drive speed: 900 min-1

Rotation angle: 1800°

Acceleration/deceleration time: 100 ms

Physical properties and chemical resistance of high-gain type rubber