Jaw Couplings High Rigidity Double Disc Carbon Steel Keyless Type

The diaphragm coupling consists of several sets of diaphragms (stainless steel thin plates) that are alternately connected to the two halves of the coupling with bolts. Each set of diaphragms is made up of multiple stacked plates.
The diaphragm coupling compensates for the relative displacement between the two connected shafts through the elastic deformation of the diaphragms. It is a high-performance flexible coupling with strong metal components.
Its features include a compact structure, zero backlash, high strength, long service life, no rotational clearance, unaffected by temperature and oil contamination, and resistance to acid, alkali, and corrosion.
Applicable motor types: Recommended for use with servo motors, stepper motors, and general-purpose motors.

The recommended tolerance for the applicable shaft is h7.
Eccentricity adjustment has been completed and assembly finished before shipment.
There are two threaded holes for removal on the keyless flange section. For hole sizes of ⌀20 and above for the locking bolts, threaded holes for removal are provided inside.
　When disassembling, screw in an M6 bolt.
　For installation and removal methods of the keyless type, please refer to the basic information for confirmation.

Please follow the selection steps to , choose the type and parameters, and then place your order. Please specify the shaft bore diameter within the range of d1 ≤ d2.

Type (Type·D)	—	d1	—	d2
E-LDBL07-D65	—	20	—	35
E-LDBL66-D65	—	18	—	22

 

Type		d1 and d2 selection (but d1 ≤ d2)														⌀D1	L	LF	LP	S	Keyless side locking screw M1	Removal screw M2
Type	D
E-LDBL07-D Keyless on both sides	65	14	15	16	17	18	19	20	22	24	25	28	30	32	35	58	90.8	25.8	15.8	5.7	M6	M6
	87			16	17	18	19	20	22	24	25	28	30	32	35	74	104	28.25	19	8.5	M6	M6

 

Type		d1 and d2 selection (but d1 ≤ d2)														⌀D1	⌀N	L	LF1	LF2	LP	S	Keyway side fixing screw M	Keyless side locking screw M1	Removal screw M2
Type	D
E-LDBL66-D	65	14	15	16	17	18	19	20	22	24	25	28	30	32	35	58	46	84	25.8	24.9	15.8	5.7	M6	M6	M6
	87			16	17	18	19	20	22	24	25	28	30	32	35	74	56	100	28.25	29	19	8.5	M8	M6	M6

■ Characteristic Values

Type		Permissible torque (N⋅m)	Permissible eccentricity (mm)	Permissible angular misalignment (°)	Permissible axial deviation (mm)	Permissible speed (RPM)	Static torsional stiffness (N.m/rad)	Moment of inertia (N.m)	Fastening screw		Weight (g)
Type	D								M	Locking torque N.m
E-LDBL07-D Keyless on both sides	65	210	0.2	0.5	±0.6	7000	38000	8.2 × 10-4	M6	7	1250
	87	390			±1	6000	50000	1.3 × 10-3	M8	15	1620

 

Type		Permissible torque (N⋅m)	Permissible eccentricity (mm)	Permissible angular misalignment (°)	Permissible axial deviation (mm)	Permissible speed (RPM)	Static torsional stiffness (N.m/rad)	Moment of inertia (N.m)	Fastening screw		Weight (g)
Type	D								M	Locking torque N.m
E-LDBL66-D Keyless on one side · Single-sided keyway hole	65	210	0.2	0.5	±0.6	7000	38000	7.9 × 10-4	M6	7	1140
	87	390			±1	6000	50000	1.0 × 10-4	M8	15	1500

The values of static torsional rigidity, moment of inertia, and weight are given for the maximum shaft diameter.

 

■ Main Features of the Diaphragm Coupling
1. Strong ability to compensate for misalignment between two shafts. Compared to gear couplings, it allows for twice the angular displacement, has lower reaction force during radial displacement, greater flexibility, and permits a certain amount of axial, radial, and angular displacement.
2. Provides significant shock absorption, with no noise and no wear.
3. Can operate safely under conditions of impact and vibration.
4. High transmission efficiency, up to 99.86%. Especially suitable for medium- and high-speed, high-power transmission.
5. Simple structure, lightweight, compact size, and easy to install and remove. Installation and removal can be done without moving the machine (refers to the type with an intermediate shaft), and no lubrication is required.
6. Can accurately transmit rotational speed, operates without slip, and can be used for precision machinery transmission.

● Installation
(1) Please wipe off any dirt from the surface of the shaft and apply a thin layer of lubricating oil or grease.
　　 (Do not use lubricating oil or grease containing molybdenum-based friction modifiers.)
　(2) Similarly, clean the contact surface of the inner diameter of the coupling and apply machine oil or grease. At the same time, apply lubricant to the threaded surface and the head contact surface of the locking bolts.
　(3) Mount the coupling onto the shaft.
　　 (Do not tighten the keyless flange with bolts if the shaft has not passed through.)
　(4) After positioning is complete, first use a torque wrench to gently tighten the locking bolts in a diagonal sequence (to about 1/4 of the specified tightening torque).
　(5) Then, increase the tightening torque (to about 1/2 of the specified tightening torque) and tighten again.
　(6) Tighten using the specified tightening torque.
　(7) Finally, tighten each locking bolt one by one in a circumferential order.

● Installation precautions
· Tighten the locking bolts after the coupling is mounted onto the shaft end.
　 (If the bolts are tightened before insertion, the bushing will become deformed.)
　· Please use a torque wrench to tighten the bolts.
　· Be sure to use the supplied bolts for the locking bolts.

● Removal
　· Please perform this work only when the equipment is completely stopped.
　· Loosen the locking bolts one by one in a circumferential order.
　· Insert the bolts into the removal threaded holes and tighten them evenly.
　· When reinstalling, repeat the steps in the "Installation" section.

■ Installation method
STEP 1 Insert the coupling
Make sure the clamping bolts are loosened, then remove any dust, foreign matter, or oil from the shaft and the coupling bore.
Next, when inserting the coupling onto the shaft, be careful not to subject the diaphragm to excessive stress such as compression or tension.
STEP 2 Adjustment using a jig
Please use a jig to precisely adjust and secure the concentricity of the left and right hubs of the coupling.
STEP 3 Simple eccentricity and angular misalignment check
With the bolts loosened, slide the coupling axially to confirm smooth operation.
Next, rotate the coupling and make sure it operates smoothly.
Eccentricity is not allowed for single-disc couplings, so please position them accurately.

STEP 4 Installation
Adjust the shaft insertion amount according to the ℓ dimension in the product catalog, and use a torque wrench to tighten to the specified torque.
*If the specified torque cannot be reached in one tightening, please tighten the left and right clamps in a crisscross pattern over 2 or 3 rounds.

■ Alignment Adjustment
1. Couplings allow for shaft misalignment, transmission of rotational angle, and torque, but if the shaft misalignment exceeds the allowable value, vibration may occur or the service life may be drastically reduced.
Be sure to perform alignment adjustment.
2. Shaft misalignment includes eccentricity (parallel error between two shaft centers), angular misalignment (angular error between two shaft centers), and axial displacement (axial movement of the shaft).
Please calibrate and adjust the shafts to ensure that the shaft misalignment is within the allowable values specified in the dimensions and performance tables of each product.
3. The allowable values for shaft misalignment listed in the dimensions and performance tables refer to the case where only one of eccentricity, angular misalignment, or axial displacement occurs individually. When two or more types of shaft misalignment occur simultaneously, the corresponding allowable values should each be halved.
4. Shaft misalignment does not only occur during assembly to the equipment; vibration during operation, thermal expansion, and bearing wear are also major causes. Therefore, it is recommended to set the shaft misalignment to less than one-third of the allowable value.