GC Coupling

	Features
	1．Torque is fully transmitted even if misalignment of shaft center or vibration occurs. 2．When misalignment or tilt of connected shafts occurs in operation, it will be automatically adjusted. As no extra load is applied to shaft and bearings, machine is well protected. 3．It is a flexible coupling using crowning gear and has high wear resistance and toughness. 4．As it is separated from center case, its assembly and removal are easy. Moreover, as it is compact and light, the mounting space can be minimized. 5．Unlike other types of flexible coupling, misalignment of rotation angle between two shafts caused by deflection of coupling cannot happen. It is suitable for the joint of line-shaft, high-speed usage and heavy-load usage.

	Features of M Series
	1．The shapes are the same as SS/SE/CC/CE types of gear coupling in JIS B1453. In catalog, there are 4 types, which are added “GC” before and“M” after JIS code such as GC-SSM, GC-SEM, GC-CCM and GC-CEM, as well as these other types;GC-SMM, GC-SAM, GC-CAM, GC-MV, GC-SV and GC-EEM. 2．The size number indicates the diameter of coupling case. Bore diameter of shaft is in compliance with JIS, while coupling overall diameter is made more compact. When compared with JIS coupling, therefore, the product is more compact in size and lighter in weight, contributing to your cost savings. 3．As coupling center is longer compared to coupling case width, shafts can be easily aligned by moving the coupling case within the range of boss length. This size also makes the teeth inspection easier. 4．The type GC-SMM for mill motor is in compliance with JEM-1109 standard. 5．Upright types (GC-MV, GC-SV) and spacer types (GC-SAM, GC-CAM) are standardized with the oil seal cover to prevent oil leakage from key way. 6．The type MH, whose transmission capacity is increased by heat treatment, is standardized. 7．The sleeve type GL, which is made more compact, is also available. 8．GC coupling and its parts are in good stock to be supplied immediately through our sales network. The sleeve type GL, which is made more compact, is also available.

Types of GC Coupling M Series


GC-SSM type GC-SSMH type	GC-SEM type GC-SEMH type	GC-CCM type GC-CCMH type	GC-CEM type GC-CEMH type


GC-SMM type	Equipped with oil seal cover	GC-CMV type GC-CMVH type	GC-SMV type GC-SMVH type


GC-SV type	GC-SAM type GC-CAM type	GC-EEM type	GC-GL type

Construction of GC Coupling

1．Construction
    GC coupling is constructed by the mesh between internal spur gear of the Coupling Case and crowned external
    spur gear of the Coupling Center. Having involute tooth profile and special design for top and bottom of the teeth
    considering tilt and lubrication, it will ensure uniform speed and smooth power transmission even if a slight tilt
    occurs between Case and Center.
    Having two gear meshes, GC-SSM and GC-CCM can always keep the Case in the neutral position and transmit
    power smoothly despite offset alignment, angular misalignment and axial gap.
    Having single gear mesh, GC-SEM and GC-CEM can accommodate angular misalignment and axial gap. As shown
    in Figure 5 on page 8 of its catalog, normally two units should be applied in combination using a floating shaft.

2．Major parts and their materials

GC-SSM type

GC-CEM type

GC-SSM type GC-SEM type	Part name	GC-CCM type GC-CEM type
①Carbon steel	Coupling Case	Carbon steel
②Carbon steel	Coupling Center	Carbon steel
③Alloy steel	Reamer bolt	Alloy steel
④Nitrile rubber	○-ring	Nitrile rubber
⑤Alloy steel	Oil plug	Alloy steel
⑥Carbon steel	Rigid	Carbon steel
⑦-	Side cover	General-use steel

GC Coupling Flexibility


Figure 1 Parallel offset	Figure 2 A section shows a gear mesh under offset and angular condition	Figure 3 Contact between internal gear and external gear teeth in meshing

    When offset misalignment exists, the coupling gear tooth tilts by tanφ=δ／L as shown in Figure 1.
    When the shafts are concentric, the gear tooth is in contact at the crowned tooth center (Ro) as shown in Figure
    3(a). However, when the shafts have offset or angular misalignment after installation,the gear tooth comes into
    contact at the point (R) away from the tooth center as shown in Figure 3(b).
    The larger the tilting angle is, the remoter point goes away from the center. Thus, the contact on arced surface
    ensures free and smooth meshing between internal gear and external gear under offset and angular misalignment.
    Our GC Couplings are designed and manufactured to have adequate crowning and backlash so that they can work
    freely and smoothly within allowable range.

Examples of misalignment


a. Parallel offset	b. Angular	c. Offset + angular	d. Axial gap

Application Examples

Roller table	Pump	Paper mill

Rolling mill	Heavy-duty crane