Note: Descriptions are shown in the official language in which they were submitted.
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[12604/1]
PRODUCTION SERIES OF ADAPTER DEVICES
AND AN ADAPTER DEVICE
The present invention relates to a production series of
adapter devices and an adapter device.
The German Patent 196 37 361 describes an adapter which is
able to transmit a certain torque. However, for industrial
applications, it is necessary to construct drives having ever
higher torque, accompanied by the most cost-effective design
possible.
Therefore, the object of the present invention is to further
develop an adapter device while avoiding the aforesaid
disadvantages. In particular, a higher torque should be
transmittable, accompanied at the same time by an inexpensive
design.
According to the invention, the objective is achieved with the
production series according to the features indicated in Claim
1 and with the adapter device according to the features
indicated in Claim 11.
Essential features of the invention in the case of the adapter
device for connecting an input shaft, particularly a motor
shaft of a motor, especially an electric motor, to a device to
be driven, particularly to a pinion of a gear unit, including
- an adapter shaft for the rotatably-fixed connection to
the device to be driven,
- an intermediate piece engaged with the adapter shaft, and
- a sub-component that is engaged with the intermediate
piece and is detachably connectable with form locking to
an input shaft, particularly a motor shaft,
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the sub-component including a bore hole for accommodating the
input shaft in the sub-component,
and the sub-component having at least three claws for forming
the coupling,
at its second end, thus the end facing the intermediate piece,
the adapter shaft having at least three claws for forming a
coupling,
and the intermediate piece being provided between the claws of
the sub-component and the claws of the adapter shaft.
Of advantage in this context is that the adapter shaft has
claws on itself. Therefore, the adapter shaft is usable
simultaneously for the rotatably-fixed connection to a pinion
of a device to be driven, and at its other end is usable as
part of a claw coupling which is formed by the claws of the
adapter shaft itself, the intermediate piece and the claws of
the sub-component. Since the claws are able to be manufactured
by processing the master pattern of the adapter shaft, the
spatial orientation, particularly the distance to the axis, as
well as all further specific geometric characteristics
relative to the axis of the adapter shaft may be so well
produced, that the need for adjusting the claws relative to
the axis of the adapter shaft is eliminated, and therefore it
is acceptable to produce the claws with the adapter shaft from
one piece. Surprisingly, it has turned out that the tolerances
are adhered to so well, that there are even improvements in
the service life and further characteristic data compared to
an adapter shaft having a separate claw coupling.
Another important advantage is also that the sub-component
includes a bore hole for accommodating the input shaft in the
sub-component, because motor shafts of various lengths are
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connectable to it depending on the different design or
standard.
A further advantage is that the intermediate piece is provided
between the claws of the adapter shaft and of the sub-
component, and therefore, in the event the intermediate piece
fails, the claws form a coupling directly, a correspondingly
large play developing. Thus, reliability is extremely high,
even in the case of breakdown. In particular, because of the
large play, in response to the failure described, a noise
develops during operation which is clearly transmittable to
the operator as a warning indication.
By integrating the claws into the adapter shaft and the
sub-component, many components existing in the related art may
be omitted. It is further advantageous that, with the aid of
the intermediate piece, on the sub-component side there is
created an interface which makes it possible to connect
various sub-components. These sub-components must only have
the same claws. For that reason, various sub-components are
useable for the production series. Therefore, the diversity of
functionalities which can be offered increases considerably,
while at the same time production expenditure is reduced
compared to the related art. For example, it is possible to
fulfill the request of the customer to provide only the
functionality of a claw coupling between the motor and gear
unit, or alternatively, to provide the functionality of an
overload coupling in addition to the functionality of a claw
coupling.
In this context, one important advantage of the claw coupling
is to compensate for geometrical deviations. An important
advantage of the overload coupling is to exhibit a desired
behavior in response to overloading. Therefore, both
advantages may be combined in the invention, the need for
parts or components simultaneously being eliminated compared
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to the related art; in particular, the connection to the
sub-component may be implemented especially simply and quickly
and at the same time without further parts which would be used
to compensate for the geometric position between a claw
coupling and an overload coupling in the case of the related
art.
In one preferred design, it is advantageous that the
intermediate piece may be selected to be more flexible, and
thus exhibit a torsional stiffness characteristic or
transmission function corresponding to a greater elasticity.
In addition, the claws are isolated from each other by the
radial sections of the intermediate piece. Thus, the coupling
attenuates torque fluctuations to be transmitted. As already
indicated above, the coupling produced by the adapter device
is fail-safe. Namely, if the intermediate piece wears out or
is stressed in response to too high a thermal load in such a
way that it is worn away, the claws ultimately meet. Thus, the
basic function of the adapter device is retained. In such an
emergency or accident, the metallic claws, by striking each
other, particularly in response to torque fluctuations, then
advantageously generate a noise which makes the operator or a
monitoring device aware of the wear and tear and therefore the
emergency.
Further advantages are that, due to the intermediate piece,
the motor shaft is allowed to extend into the adapter shaft,
and therefore the entire adapter device may be implemented in
a very compact fashion. In addition, the adapter shaft has
claws. Consequently, a coupling function is advantageously
integrated into a shaft, thus the adapter shaft. A
particularly compact design is thereby achieved which has
fewer junctions and/or connections and makes the use of a
separate coupling unnecessary. This is a decisive advantage
when the invention is used within a production series of gear
units and motors. Therefore, the adapter device may
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advantageously be optimized for the power to be transmitted
and for the frame sizes and bore-hole dimensions and/or shaft
dimensions used in the production series of gear units and
motors.
Since the adapter shaft and the coupling part with their
respective claws are able to be implemented in metal and the
number of claws is three or more, large torques are able to be
transmitted. In particular, the number of claws may
advantageously be optimized in such a way that to the greatest
extent possible, all material parts transmit as much force
and/or torque as possible. Moreover, there are no substantial
material areas which are unused.
With respect to the intermediate piece, in one preferred
design, radial sections are arranged in the radial direction
starting in each case from the base member. The base member of
the intermediate piece has a bore hole, and the diameter of
this bore hole is greater than the diameter of the input
shaft, particularly the motor shaft. The radial sections of
the intermediate piece are disposed between the claws of the
adapter shaft and the claws of the coupling part, and are
convex in the radial direction. Each of the radial sections
has such a thickness profile in the radial direction, and the
claws or their flanks are curved and/or formed radially in
such a way in the circumferential direction that under nominal
load, the radial sections subject the base member of the
intermediate piece to pressure in the radial direction. The
radial sections have spacers in the axial direction to the
adapter shaft and to the coupling part. The radial sections
are each arranged in the radial direction starting from the
base member. Due to the special formation of the radial
sections and due to the formation of the claws, under load,
the material of the radial sections is pushed in the direction
of the base member, so that a pressure is able to be exerted
on it in the radial direction. Therefore, advantageously no
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material is squeezed to the outside, which would cause the
intermediate piece to wear more quickly.
The torsional stiffness characteristic or transmission
function of the adapter device is likewise variable by the
specially selectable design of the radial sections.
The integration of the spacers for maintaining axial distances
into the intermediate piece is advantageously extremely
cost-effective, and results in an even more compact
construction.
In particular, the star-shaped configuration of the
intermediate piece and the compact construction described
interact in such a way that all in all, an extremely compact
coupling function is produced accompanied at the same time by
extremely high transferable torque. The adapter shaft with its
claws is manufactured from one piece, and the sub-component
with its claws is manufactured from one piece, or the
sub-component includes a driver part which has the claws and
is produced with these claws from one piece.
In one preferred implementation, after the intermediate piece
has failed, particularly due to chemically or mechanically
caused breakdown, the claws of the sub-component and the claws
of the adapter shaft form a play-encumbered, form-locking
connection. Thus, the adapter device exhibits increased
reliability.
In one preferred embodiment, the sub-component is able to be
variably designed for forming different variants of a
production series; for the form-locking connection to an input
shaft, it being possible to provide
- either a coupling part which is engaged with the
intermediate piece and is detachably connectable with form
locking to the input shaft,
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- or an overload coupling which is engaged with the
intermediate piece and is detachably connectable with form
locking to the input shaft, particularly by a feather key
connection
as sub-component. In this context, it is advantageous that it
is possible to offer functionalities which differ greatly
depending on the application, accompanied by simultaneous
ability to rationalize production, the lowering of storage
costs and a very compact type of design.
In one preferred variant, at its end area facing away from the
intermediate piece, the adapter shaft has a feather keyway for
the connection to a pinion of a gear unit as the device to be
driven.
In one preferred construction, the intermediate piece includes
a base member and at least six radial sections arranged in the
shape of a star. Advantageous in this case is that the radial
sections are able to be mounted together, and at the same time
easily and quickly, because the base member connects them. In
addition, the number of radial sections is at least six, an
optimal value for compressive load per unit area thereby being
attainable.
In one preferred design, to accommodate the input shaft, the
sub-component has a bore hole and is connectable to the input
shaft by a feather key connection. This is a detachable
connecting technique and thus permits quick and easy assembly,
servicing or exchange of components.
In one preferred embodiment, the adapter shaft has a bore hole
such that, and the diameter of this bore hole is greater than
the diameter of the input shaft such that the end of the input
shaft on the adapter shaft side is insertable into the adapter
shaft and/or may be provided in a manner that it is able to
extend into the adapter shaft without engaging with the
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adapter shaft. Therefore, different lengths of the motor shaft
may be used depending on the standard.
Essential features of the invention with respect to the
production series of adapter~devices is that the production
series includes at least one size and each size includes at
least one variant;
and each adapter device including at least
- an adapter shaft 1 for the connection to a device to be
driven,
- an intermediate piece 2 engaged with adapter shaft 1, and
- a sub-component, engaged with intermediate piece 2, for
connection to an input shaft, particularly a motor shaft;
and each variant being characterized at least by
- a diameter A i of a bore hole for accommodating the input
shaft in the sub-component,
- an intermediate piece 2, and
- a diameter D-i at the end of adapter shaft 1 facing away
from intermediate piece 2,
i being a numbering index;
and the diameters A i of the bore holes for accommodating the
input shaft in the sub-component being included by a
standardized motor grading;
and in the case of the production series, with increasing
characteristic power, the diameters D_i at least not become
smaller;
and each intermediate piece 2 used in the production series
having radial sections 6 which are designed such that, at the
greatest power provided for the respective intermediate piece
and/or characteristic power, they are in each case subjected
to a value of compressive load per unit area lying within a
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single tolerance range determined for the entire production
series;
and at least one intermediate piece 2 being used in variants
of at least two different sizes
and/or
at least one intermediate piece 2 being used for
sub-components having a different diameter A i of the bore
hole for accommodating the input shaft, and for adapter shafts
having different diameters D_i in the area of feather keyway
11 of adapter shaft 1.
In particular, for each variant, the characteristic power is
the nominal power or the power to be transferred in each
instance or the maximum transferable power. An important
advantage is that, to achieve the objective of the invention,
a production series is formed having special features. These
features have the advantage, inter alia, of multiple usability
within the production series, thus also reduction in storage
costs, and the similar processing of parts, thus easier and
faster production.
Another advantage is that the material of the intermediate
piece is capable of being loaded up to its limit, and is
nevertheless usable repeatedly within the production series.
Consequently, the adapter device is in each case able to be
implemented with very small volume and the storage costs are
kept low, and nevertheless a great variety of alternatives is
made possible. In addition, an intermediate piece is used for
coupling parts having in each case a different diameter A i of
the bore hole for accommodating the motor shaft and for
adapter shafts having different diameters D_i in the area of
the feather keyway of the adapter shaft. This means that not
only the customary production series offered by the
manufacturer, which has no filled 2*2 sub-matrices in its
matrix, thus in the two-dimensional numerical schema formed
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from all tuples of two, but also additional special designs of
the production series are included. This is expressed in table
form in filled 2*2 sub- matrices.
Consequently, a new production series is used which is unknown
from the related art but which has special cost advantages and
is customer-friendly without extra cost.
The fact that toward the motor, the adapter devices have
diameters of a standardized motor grading is customer-friendly
and reduces the need for special designs for special diameters
of the motor journal.
In a further advantageous refinement, the compressive load per
unit area is determined in the middle of the cam lobes, and
the number of radial sections that are loaded in each case is
taken into account. In this context, it is advantageous that
an approximate value of the physical compressive load per unit
area is able to be calculated in a simple manner.
In another advantageous refinement, the number of radial
sections loaded in each case is 3 or 4, the total number of
radial sections being 6 or 8. The advantage here is that the
radial sections are not too thin, thus exhibit a high
stability, and under load, at least 3 radial sections are
always loaded.
In another advantageous embodiment, the tolerance range
includes values from 2 N/mm~2 to 3.2 N/mm~2. In this case, it
is advantageous that the material polyurethane is usable for
the intermediate piece.
In another advantageous development, the standardized motor
series is an IEC standardized motor grading or a NEMA
standardized motor grading. Advantageous in this instance is
that motor production series, customary in the market,
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according to international or U.S. American standard are
usable.
In a further advantageous refinement, the production series is
included by a larger production series. The advantage in this
case is that, given very large or very small powers to be
transmitted, it is also possible to use other adapter devices
having, for example, different compressive loads per unit
area, or the production series of the present invention is
included in a production series which also has intermediate
values for diameters D a and A a, and therefore offers a still
larger selection to the customer.
In another advantageous refinement, the adapter device in the
production series includes an adapter shaft which, at its
first end, is connectable in a rotatably fixed manner to a
pinion, and at its second end, has at least three claws for
forming a coupling. An important advantage in this instance is
that the adapter shaft is designed as one part, and thus it is
possible to dispense with parts and the production series may
be implemented in a particularly cost-effective manner.
Further advantageous developments are yielded from the
dependent claims.
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Reference Numeral List
1 adapter shaft
2 intermediate piece
3 coupling part
4 claws of the adapter shaft
5 base member
6 radial section
7 spacer
8 claws of the coupling part
9 feather keyway of the coupling part
10 motor shaft
11 feather keyway of the adapter shaft
12 feather keyway of the motor shaft
13 feather key
51 driver part
52 screws
53 other coupling part
58 claws
61 tapped hole
62 coupling hub
63 guide bush
64 brake disk
65 brake liners
66 slotted nut
67 disk spring
68 thrust ring
71 tapped hole
72 coupling hub
73 retaining ring
74 bearing
75 collar ring
76 ball
77 slotted nut
78 disk springs
79 thrust ring
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The invention shall now be explained in detail with reference
to the figures.
Figure 1 shows a half section, which in the upper half shows a
design having a reversal preventing device, and in the lower
half shows a simple design.
Motor shaft 10 is mounted via a feather key 13 which is
inserted in feather keyway 9 of coupling part 3 and in feather
keyway 12 of the motor shaft, and represents a connection for
transmitting torque. Intermediate piece 2 having base member 5
and radial sections 6 is positioned between coupling part 3
and adapter shaft 1.
Adapter shaft 1 has a feather keyway 11 for the connection to
a pinion of a gear unit as the device to be driven.
Figure 2 shows an exploded drawing of the adapter device
according to the present invention.
At its first end, adapter shaft 1 again has a feather keyway
11 for the connection to a pinion of a gear unit. In addition,
integrated at its second end are claws 4 which have curved
flanks in the radial direction. Intermediate piece 2 features
base member 5, radial section 6 and spacer 7. It lies with its
radial sections 6 between the claws of adapter shaft 1 and
claws 8 of coupling part 3, which includes a feather keyway 9
for receiving feather key 13.
The flanks of claws 4, 8 are curved in such a way and the
radial sections have a convex design such that, under load,
particularly rated load or overload, the flexible material of
radial sections 6 of intermediate piece 2 is not pressed
radially to the outside, but rather radially to the inside
toward the axis. Consequently, radial sections 6 then exert a
force or a pressure in the radial direction on base member 5.
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The wear and tear of the intermediate piece is reduced in this
manner. Spacers 7 keep adapter shaft 1 and coupling part 3
apart.
Radial sections 6 have a convex shape in the axial, radial and
circumferential direction in order, in interaction with the
convex shape of the flanks of claws 4, 8 in the radial
direction and in the circumferential direction, to exert the
indicated radially directed force on the base member.
After intermediate piece 2 has worn, for example, in an
emergency case, the coupling is not allowed to spin, since
claws 4, 8 guarantee safety against breakdown.
Figure 3 shows an exemplary embodiment according to the
invention for an IEC grading. Motor power P of the production
series is entered in the first line; below it are the
appertaining diameters A_i of the bore holes of coupling part
3 from the IEC-Standard grading, which are assigned to the
outside diameters of the motor journals. In this context,
index i runs from 1 to 10.
Entered in the left column are the diameters D,i of the pinion
journals, thus the diameters D-i of adapter shaft 1 for
connection to a pinion in the region of feather keyway 11 of
adapter shaft 1. They belong to the manufacturer s own grading
of the gear unit manufacturer. In this context, index i runs
from 1 to 9. With rising index, the value of diameter D i
increases. Each value D-i is less than the corresponding value
3 0 A i having the same index i ; thus , Dl < A1, Dz < Az , and so
forth, is always applicable. Diameters D_i and the power to be
transmitted in each case are therefore adjusted in such a way
that a possibly slightly oversized standardized motor grading
of diameters A i is usable, and at the same time, the adapter
device is designed as optimally, particularly as small, as
possible.
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Intermediate pieces K1, K2, K3, K4, K5, K6 for the respective
motor journals and pinion journals are entered in the-matrix.
They are rated in such a way that under load, radial sections
6 axe subjected to an approximately equal compressive load per
unit area, at the greatest power to be transmitted. The value
of the compressive load per unit area lies in a tolerance
range around 2.7 N/mm~2, and includes essentially values from
2.6 to 2.8 N/mm~2. At small or large powers, values such as
3.2 or 2.3 N/mm~2 may also occur. Therefore, essentially a
special polyurethane is usable, which may be utilized very
well or to the maximum.
Intermediate pieces K2 and K5 fill in 2*2 sub-matrices. This
means that in the production series, these intermediate pieces
are usable for various diameters A i and D i, and therefore
not only the standard production series of the manufacturer
can be offered, but also special constructions within the
production series according to the present invention are
feasible, without additional expenditure of time and energy or
additional costs. Thus, the intermediate pieces are usable
repeatedly within the production series.
Figure 4 shows an exemplary embodiment of the present
invention for a NEMA grading of diameters A-i which are again
indicated in mm. The production series according to Figure 4
likewise shows multiple usage, with the advantages indicated.
An important further advantage of the invention is that the
same intermediate pieces K1 through K6 are usable for the
production series according to Figure 4 with NEMA grading and
for the production series according to Figure 3 with IEC
grading of diameters A i.
Figure 5 again shows the exemplary embodiment of the present
invention according to Figure 2, including the components
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adapter shaft 1, intermediate piece 2 and coupling part 3.
However, coupling part 3 is pushed to one side. In addition, a
driver part 51 and another coupling part 53 are shown. Driver
part 51 has claws 58 which are equal to claws 8 of coupling
part 3, and it may be joined to the other coupling part 53 by
screws 52. Driver part 51 and the other coupling part 53
together form a coupling.
In different exemplary embodiments of the present invention,
the coupling is designed according to various acting
principles. It is extremely advantageous to design the
coupling according to the type of so-called overload coupling.
In this manner, intermediate piece 2 is just as protected as
claws 4 of the adapter shaft and claws 8 of coupling part 3.
Naturally, the input and output devices are also protected.
The transmission characteristic of an overload coupling is
always such that, when the load is unacceptably high, the
transmission characteristic no longer corresponds to the
transmission characteristic at rated load, and therefore the
input and output devices are protected. Such overload
couplings are generally known and have widely varying designs.
They may be classified according to their acting principles.
They are of the automatic switching type, or the non-automatic
switching type. Moreover, the overload couplings may be
classified according to load-disconnecting or load-retaining
transmission characteristic. Further classification features
are fractionally-engaged, form-locking or continuous-material
characteristics.
According to Figures 6 and 7, a release coupling and a
friction coupling are sketched schematically as specific
exemplary embodiments of the present invention. However, in
furtherance of the inventive principle for one skilled in the
art, particularly of the integration of claws into the driver
part of a coupling, which, except for the reguirement of the
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inclusion of at least one driver part, is as desired, various
further couplings may advantageously be used.
A friction coupling is sketched schematically in Figure 6. The
shaft on the input side, particularly one driven by an
electric motor, is connected to coupling hub 62 by a feather
key connection. Disposed about guide bush 63 is brake disk 64
which has tapped holes 61 and, with the aid of screws 52 that
may be detachably connected to these tapped holes 61, is
connectible to driver part 51 including claws 58.
With the assistance of claws 58, the friction coupling is
engaged with intermediate piece 2 in a corresponding manner as
coupling part 3 with its claws.
Slotted nut 66 is screwed onto coupling hub 62 and exerts
force on thrust ring 68 via disk springs 67. Therefore, thrust
ring 68 causes brake liners 65 to press against brake disk 64.
Brake disk 64 slips only when a critical value for the
transmitted torque is exceeded. Consequently, the input and
output devices and the adapter device itself are protected.
Figure 6 only shows the acting principle of the friction
coupling schematically. Therefore, using his/her specialized
knowledge, one skilled in the art is in the position to add
further components to refine the friction coupling.
A release coupling is sketched schematically in Figure 7. The
shaft on the input side, particularly one driven by an
electric motor, is connected to coupling hub 72 by a feather
key connection. Disposed about coupling hub 72 by way of a
bearing 74 is collar ring 75, in which balls 76 are located as
long as no critical value of torque is yet transmitted. In
this context, thrust ring 79 is pressed onto balls 76 by disk
springs 78 which are braced against slotted nut 77. Retaining
ring 73 represents an axial limitation for bearing 74.
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Driver part 51 including claws 58 is connectable by screws 52
which may be detachably connected to tapped holes 71 of collar
ring 75.
With the assistance of claws 58, the release coupling is
engaged with intermediate piece 2 in a corresponding manner as
coupling part 3 with its claws.
Figure 7 only shows the acting principle of the release
coupling schematically. Therefore, using his/her specialized
knowledge, one skilled in the art is in the position to add
further components to refine the release coupling.
Thus, in Figure 5, the production series of adapter devices
already described is expanded in its variety in such a way
that, on the input side, it is possible to build onto coupling
part 3 by various driver parts 51 together with other coupling
parts 53, depending on the request of the customer or other
requirement. The claws which are engaged with intermediate
piece 2 are equal to the claws of coupling part 3 and in the
case of driver part 51 are integrated, in particular are
worked out from one work piece in one processing operation.
Thus, when no feather key is desired on the input side, an
overload coupling of a selectable acting principle may be
provided.
In further exemplary embodiments of the present invention,
with respect to the overload coupling, a sensor is mounted
which detects an event in the case of an overload. With
respect to the release coupling, for example, an inductive
sensor is advantageous for this purpose which detects the
relative distance of spherical calotte 75 and thrust ring 79.
Instead of inductive sensors, other sensors may also be used
which are able to detect correspondingly linear distances.
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Analogously, with respect to the friction coupling, sensors
are advantageous which detect the relative movement of the
brake disk against brake liners 65, coupling hub 62 or slotted
nut 66.
For the release coupling, it is also possible to monitor an
electrical contact between thrust ring 79 and collar ring 75.
In the instances indicated, the sensor or the monitoring of
the electrical contact supplies information about the overload
case. This information is passed on, made audible acoustically
or indicated visually.
In particular, in the event of overload, it is even possible
to switch off the entire drive or to reduce the torque
produced by the electric motor torque.
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