Fxn Internal Freewheels for Press Fit on The Outer Ring

• Type: Motorcycle Transmissions
• Certification: ISO9001: 2000
• Material: Gcr15
• Model: Fxn38 - 17/70
• Inner Diameter: 25mm
• Outer Diameter: 70mm
• Model NO.: FXN38 - 17/70
• Weight: 0.4kg
• Width: 24mm
• Oen: Accpet
• Precision: P6
• OEM: Accept
• Port: Shanghai;Ningbo
• Delivery: 10-15days
• Transport Package: Single Box or as Your Requirements
• Specification: P6
• Trademark: SUMA or OEM
• Origin: Changzhou, Jiangsu, China
• HS Code: 84836000
• Production Capacity: 10000PCS/Month

Product Description

Internal Freewheels FXN
for press fit on the outer ring
with sprag lift-off X
 
Features
Internal Freewheels FXN are sprag freewheels without bearing support and with sprag lift-off
X. The sprag lift-off X ensures a wear-free free - wheeling operation when the inner ring rotates
at high speed. The outer ring is pressed into the customer hous ing. This makes compact, space-saving fitting solutions possible. The freewheels FXN are used as:
 Backstops
 Overrunning Clutches
for applications with high speed freewheeling operation and when used as an overrunning
clutch with low speed driving operation. Nominal torques up to 20 500 Nm. The torque is
transmitted on the outer ring by press fit. Bores up to 130 mm. Many standard bores are
available.
 
Sprag lift-off X
Internal Freewheels FXN are equipped with sprag lift-off X. The sprag lift-off X is used for
backstops and overrunning clutches, provided that in freewheeling operation the inner ring is
rotating at high speed and providing with overrunning clutches that the driving operation
is conducted at low speed. In freewheeling operation, the centrifugal force FC causes the
sprag to lift off from the outer track. In this operating state, the freewheel works wear-free,
i.e. with unlimited service life.
 
The Figure shows a freewheel with sprag liftoff X in freewheeling operation. The sprags,
which are supported in a cage connected with the inner ring, rotate with the inner ring. The
centrifugal force FC that is applied in the center of gravity S of the sprag turns the sprag counterclockwise and rests against the support ring of the cage. This results in the gap a between the sprag and the outer track; the freewheel works with out contact. If the inner ring speed decreases to such an extent that the effect of the centrifugal force on the sprag is less than that of the spring force FF , the sprag again rests on the outer ring and the freewheel is ready to lock. If used as an overrunning clutch, the driving speed must not exceed 40% of the lift-off speed.
 

Freewheel size	mm	mm	Bore d		mm	mm	max. mm	B	D mm	F	J	K min. mm	L	Weight kg
			Standard					mm		mm	mm		mm
			mm mm
FXN31 - 17/60	20*						20*	25	60 P6	55	31	85	24	0,3
FXN31 - 17/62	20*						20*	25	62 P6	55	31	85	24	0,4
FXN38 - 17/70	25*						25*	25	70 P6	62	38	90	24	0,4
FXN46 - 25/80	25						30	35	80 P6	70	46	95	35	0,8
FXN51 - 25/85	25	30	35				36	35	85 P6	75	51	105	35	0,8
FXN56 - 25/90	35						40	35	90 P6	80	56	110	35	0,9
FXN61 - 19/95	30	35	40				45*	26	95 P6	85	61	120	25	0,8
FXN61 - 19/106	30	35	40				45*	25	106 H7	85	61	120	25	1,2
FXN66 - 25/100	35	40	45				48*	30	100 P6	90	66	132	35	1,1
FXN66 - 25/110	35	40	45				48*	40	110 P6	90	66	132	35	1,8
FXN76 - 25/115	45	55					60*	40	115 P6	100	76	140	35	1,7
FXN76 - 25/120	45	55					60*	32	120 J6	100	76	140	35	1,8
FXN86 - 25/125	40	45	50	60	65		70*	40	125 P6	110	86	150	40	2,3
FXN86 - 25/130	40	45	50	60	65		70*	40	130 P6	110	86	150	40	2,6
FXN 101 - 25/140	55	70					75	45	140 P6	125	101	175	50	3,1
FXN 101 - 25/149	70						75	62	149 H6	125	101	175	62	4,2
FXN 101 - 25/150	55	70					75	45	150 P6	125	101	175	50	3,6
FXN 85 - 40/140	45	50	60	65			65	45	140 P6	125	85	175	60	3,2
FXN 85 - 40/150	45	50	60	65			65	45	150 P6	125	85	175	60	4,2
FXN 100 - 40/160	45	50	55	60	70	75	75	50	160 P6	140	100	190	60	5,1
FXN 105 - 50/165	80						80	62	165 P6	145	105	195	62	5,8
FXN 120 - 50/198	60	65	70	75	80	95	95	70	198 H6	160	120	210	70	8,6
FXN 140 - 50/215	65	90	100	110			110	69	215 J6	180	140	245	70	14,0
FXN 170 - 63/258	70	85	100	120			130	80	258 H6	210	170	290	80	21,0

 
Application example
Internal Freewheel FXN 38 - 17/70 NX as a backstop, arranged in a housing adapter to attach to an electric motor. The thin outer ring that is pressed into the housing enables a space-efficient fitting solution. Due to the high shaft speeds in normal operation (freewheeling
operation), the sprag lift-off X ensures a contactless and hence wear-free continuous oper -ation.
 
Application example
Internal Freewheel FXN 66 - 25/100 NX as an overrunning clutch in the creep drive of a textile
machine. The freewheel installation is compactly solved by means of the thin outer ring
that is pressed into the worm wheel. During setup, the machine is driven by the worm gear and
the freewheel that is working in driving operation. In normal operation (freewheeling oper ation), the inner ring that is located on the high speed main drive shaft overruns and automatically disengages the creep drive. With the high overrunning speed of the inner ring, the type with sprag lift-off X is used; the sprags work in freewheeling operation without contact and hence are wear-free.
 
Application example
Internal Freewheel FXN 85 - 40/140 MX as a backstop fitted to the end of the first inter mediate
shaft of a spur gearbox in the drive of an inclined conveyor belt. In the case of a motor
stop the conveyor belt must be held securely so that the conveyor goods do not pull the belt
backwards and possibly cause serious damage. Due to the high shaft speeds in normal oper ation (free wheeling operation), the sprag lift-off X ensures a contactless and hence wear-free
continuous operation.
 
Mounting
Internal Freewheels FXN are without bearing support. Concentric alignment of inner and
outer ring must be provided by the customer. The permissible run out (T.I.R.) must be observed. The torque is transmitted on the outer ring by press fit. In order to transmit the torques specified in the table, the outer ring must be accommodated in a housing with an external diameter K. The housing is made of steel or grey cast iron in minimum quality GG-20. When using other housing materials or smaller external diameters, we urge you to contact us regarding the transmissible torque. The tolerance of the housing bore is specified in the table under dimension D. The tolerance of the shaft must be ISO h6 or j6.
 
Lubrication
At speeds in excess of the sprag lift-off speed, no special lubrication is required; the freewheel
functions maintenance-free. When operating below the sprag lift-off speed, an oil lubrication of the specified quality must be provided.
Example for ordering
Freewheel size FXN 61 - 19/95, type with sprag
lift-off X and 35 mm bore:
? FXN 61-19/95 NX, d = 35 mm