Integrated Freewheels FXRV and FXRT
for bolting to the face
with sprag lift-off X and torque limiting
Features
Integrated Freewheels FXRV and FXRT are sprag freewheels without bearing support and with sprag lift-off X. They consist of the Integrated Freewheels FXM with additional torque limiter. The sprag lift-off X ensures a wear-free freewheeling operation when the inner ring rotates at high speed. The freewheels FXRV and FXRT are used as:
Backstops
for continuous conveyor installations with multiple drives in which each drive is equipped with
its own backstop. In such continuous conveyor installations with multiple drives it is important
to consider the problem of the unequal distribution of backdriving torque to the individual
drives and backstops. As soon as the installation comes to a standstill, the entire backdriving torque is applied primarily to a single backstop, due to differences in the play and elasticity of
the drives involved. In installations equipped with backstops without torque limiters, the individual gearboxes and the corresponding backstops must be designed to accommodate
the entire backdriving torque of the conveyor installation in order to ensure safety.
The problem of the unequal distribution of backdriving torque is solved by using backstops
FXRV and FXRT with torque limiting. The torque limiter which is built into the backstop slips
temporarily when the specified torque is exceeded until the other backstops engage in succession. In this way, the entire backdriving torque of the conveyor installation is distributed
to the individual gearboxes and backstops. Furthermore, dynamic peak torques which occur during the locking process are reduced, thereby protecting the gearboxes against damaging
peak torques. For this reason the use of backstops FXRV and FXRT with torque limiting
in continuous conveyor installations with multiple drives enables the application of gearboxes
with smaller dimensions.
Advantages
1. Protection of gearboxes from overload by unequal load distribution in multiple drives
2.Protection of gearboxes from dynamic peak torques during the locking process
3. Smaller gearboxes can be used without negatively effecting the safety
4.Protection of the backstops, as dynamic peak torques are reduced by temporarly slipping
| Freewheel Size |
Type |
Slipping torque
MR
Nm |
Sprag lift-off at inner
ring speed min-1 |
Max. speed
Inner ring freewheels min-1 |
mm |
mm |
Bore d
Standard
mm mm |
mm |
mm |
max. mm |
A
mm |
B
mm |
C
mm |
D
mm |
G** |
H
mm |
K
mm |
L
mm |
O
mm |
R
mm |
S
mm |
T
mm |
min. mm |
U***
max. mm |
V
mm |
Z** |
kg |
| FXRT 85 - 40 |
MX |
1 400 |
430 |
6 000 |
45 |
50 |
60 |
65 |
|
|
65 |
330 |
148 |
6 |
295 |
M 12 |
37 |
29 |
60 |
127 |
280 |
110 |
308 |
165 |
215 |
43 |
6 |
60 |
| FXRT 100 - 50 |
MX |
2 300 |
400 |
4 500 |
45 |
50 |
55 |
60 |
70 |
75 |
80* |
350 |
159 |
6 |
311 |
M 12 |
39 |
31 |
70 |
134 |
300 |
125 |
328 |
180 |
240 |
38 |
6 |
66 |
| FXRT 120 - 50 |
MX |
3 400 |
320 |
4 000 |
60 |
65 |
70 |
75 |
80 |
95 |
95 |
400 |
159 |
6 |
360 |
M 16 |
36 |
31 |
70 |
134 |
340 |
145 |
373 |
200 |
260 |
38 |
6 |
87 |
| FXRT 140 - 50 |
MX |
4 500 |
320 |
3 000 |
65 |
90 |
100 |
110 |
|
|
110 |
430 |
163 |
6 |
386 |
M 16 |
36 |
31 |
70 |
134 |
375 |
165 |
403 |
220 |
280 |
50 |
6 |
104 |
| FXRT 170 - 63 |
MX |
9 000 |
250 |
2 700 |
70 |
85 |
90 |
100 |
120 |
|
130 |
500 |
188 |
6 |
460 |
M 16 |
43 |
40 |
80 |
156 |
425 |
196 |
473 |
250 |
340 |
38 |
6 |
166 |
| FXRT 200 - 63 |
MX |
12 500 |
240 |
2 100 |
130 |
|
|
|
|
|
155 |
555 |
188 |
6 |
516 |
M 16 |
49 |
40 |
80 |
156 |
495 |
226 |
528 |
275 |
390 |
38 |
6 |
209 |
| FXRT 240 - 63 |
LX |
21 200 |
220 |
3 000 |
|
|
|
|
|
|
185 |
710 |
210 |
8 |
630 |
M 20 |
50 |
50 |
90 |
170 |
630 |
290 |
670 |
355 |
455 |
45 |
12 |
355 |
| FXRT 260 - 63 |
LX |
30 000 |
210 |
2 500 |
|
|
|
|
|
|
205 |
750 |
223 |
8 |
670 |
M 20 |
50 |
50 |
105 |
183 |
670 |
310 |
710 |
375 |
500 |
40 |
12 |
418 |
| FXRT 290 - 70 |
LX |
42 500 |
200 |
2 500 |
|
|
|
|
|
|
230 |
850 |
243 |
8 |
755 |
M 24 |
52 |
50 |
105 |
190 |
730 |
335 |
800 |
405 |
560 |
48 |
12 |
574 |
| FXRT 310 - 96 |
LX |
53 000 |
195 |
2 100 |
|
|
|
|
|
|
240 |
900 |
293 |
10 |
800 |
M 24 |
63 |
63 |
120 |
240 |
775 |
355 |
850 |
435 |
600 |
69 |
12 |
805 |
Torques
The Integrated Freewheels FXRT are supplied with a set slipping torque MR of the torque
limiter. The static backdriving torque ML of the installation (also in the case of an overload)
must under no circumstances achieve the sum of the slipping torques MR of the provided
Integrated Freewheels. The slipping torques MR specified in the table are maximum values;
lower values can be set.
Mounting
The Integrated Freewheels FXRT are without bearing support, therefore it must be ensured
that the run out (T.I.R.) between the pilot diameter R and the shaft diameter d does not
exceed the value 0,25 mm. Dimension C applies for the Integrated Freewheel. The centering depth of the customer attachment part must be at least C + 0,2 mm. The tolerance of the pilot diameter R of the attachment part must be ISO H7. The tolerance of the shaft must be ISO h6 or j6.
Release function
The finely controllable release function consists basically of three special screws (2) that are located in the spring pocket (1) and the safety tabs (3). To release the backstop, first of all the
special screws have to be unscrewed slightly. Then the cylinder screws (4) and the safety tabs
have to be removed. The special screws can then be tightened, whereupon, with the aid of
the belleville spring set (5) the release procedure is finely initiated.
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