Title of Invention

DEVICE AND METHOD FOR FIXING BALANCING WEIGHTS TO ROTORS, IN PARTICULAR TO ARTICULATED SHAFTS OR CARDAN SHAFTS

Abstract Device for fastening balancing weights to rotors comprising a plurality of compensation planes, in particular to propeller shafts or cardan shafts, preferably in a balancing machine which comprises at least one gripper-like device which can be positioned along the rotor axis, with which device a balancing weight can be placed on the outer periphery of the rotor and fastened there, characterized in that the gripper-like device is constructed as to receive a plurality of balancing weights that comprises two gripper units mounted so as to float relative to each other in the gripper closing direction, the units being jointly displaceable in the longitudinal direction of the rotor until they abut with one gripper unit on the rotor and the other gripper unit can be placed on the rotor by relative displacement with respect to the first gripper unit. To, The Controller of Patents 21 FEB 2006 The Patent Office Mumbai.
Full Text FORM 2
THE PATENTS ACT, 1970 (39 of 1970)


ION
COMPLETE SPECIFICAT [See Section 10, rule

DEVICE AND METHOD FOR FIXING.BALANCING WEIGHTS TO ROTORS, IN PARTICULAR TO ARTICULATED SHAFTS OR CARDAN SHAFTS
SCHENCK ROTEC GMBH of LANDWEHRSTRASSE 55, D-64293 DARMSTADT, GERMANY, GERMAN Company
The following specification particularly describes the nature of the invention and the manner in which it is to be performed : -



GRANTED
21-2-2006

I Device and method Tor fastening balancing weights to rotors, in particular to propeller
i shafts or cardan shafts
The invention relates to a device for fastening balancing weights to rotors'comprising a plurality of compensation planes, in.particular to propeller shafts or cardan shafts, preferably in a balancing machine which comprises at least one gripper-likc device,which can be positioned along the'rotor axis, with which device a balancing weight can be placed on the outer periphery of the rotor and fastened there, and to a method for fastening balancing weights to rotors by means of the gripper-like device.
Devices and methods of the type mentioned al the outset are used in series production to economically balance relatively large unit numbers of rotors which comprise a plurality of compensation planes, for example propeller shafts or cardan shafts.
It is known from DE 44 40 812 Al to arrange a rotor, for example a cardan shaft, in a balancing machine, to ascertain the imbalance in terms of size and angular position and to then place balancing weights in the compensation planes of the cardan shaft on the periphery of the rotor by means of at least one gripper-like device associated with the balancing machine, and to fasten them. For this purpose, the balancing weight is received by a unit of the gripper-like device, which gripper-like device is brought into the compensation position and the rotor rotated into the correct angular position. The balancing weight is then fastened, for example, by means of a gluing or welding operation. A gripper-like device is provided in each compensation plane for compensating imbalances in a plurality of compensation planes. Instead of this, a gripper-like device displaceable only along the rotor axis may be provided which is displaced into the relevant compensation plane in each case. Irrespective of whether one or more gripper-likc devices arc provided, there is expensive equipping of the gripper-like device with a balancing weight which is requiiied at this balancing point for each balancing step.
The object of the [invention is to allow a simple and inexpensive application of the requisite
balancing weights in a device and a method of the type mentioned at the outset.



The object is achieved according to the invention in that, in a device of the type mentioned at the outset, the gripper-like device is constructed to receive a plurality of balancing weights. For fastening by means of.the gripper-like device, a plurality of balancing weights is moved transversely to the longitudinal direction of the motor and a selected balancing weight is placed and fastened on the periphery of the rotor.
Fully automatic compensation of imbalances is easily possible with the invention, wherein all balancing weights for complete compensation of imbalances of a rotor are fastened to the rotor by means of just one gripper-like device, without intermediate provision of balancing weights being necessary. This also includes a second supplementary imbalance compensation step which may possibly be necessary and which takes place in a compensation plane of the rotor closely adjacent in the longitudinal direction thereof. The gripper-like device can advantageously be equipped with balancing weights at just one suitable loading station. This can take place by means of an automatic equipping device or else via the operator. The frequency and/or the duration of the equipping operation is reduced, so, for example, two balancing machines for propeller shafts or cardan shafts can be serviced by just one operator in quick succession. This applies in particular when only a single loading station is provided for equipping alplurality of balancing machines and this is ergonomically advantageously located, for example, between the balancjng machines or is arranged at the ends thereof. Production costs are lower as a result of the lower complexity owing to only one gripper-like
device and the simplification of equipping with balancing weights.

i Advantageous in design is a configuration of the invention in which, in a gripper-like
fastening device with two gripper units, preferably the lower unit comprises a (receiver part,
which can be displaced with respect to the unit and transversely to the longitudinal direction
of the rotor, for receiving a plurality of balancing weights, as in this case conventional
carriage solutions can be used and only small inertia masses have to be moved. By using the

lower gripper unit dispensed wilh.

a holding device for the received balancing weights can generally be

An embodiment of the invention in which the two gripper units can be jointly displaced along the rotor axis is very simple in construction.

In an embodiment of the invention wherein the receiver part comprises receivers for
balancing weights which are arranged in the manner of a matrix transversely to the
I longitudinal direction of the rotor and in the longitudinal, direction of the rotor, it is possible
i
to keep in stock different forms of balancing weight or different balancing weight materials,
\ i
for example shed steel or strips of sheet aluminium for welding on. Rotors which are
different in terms of form or material may also be balanced in mixed operation. The
application, in other words the placing and subsequent fastening of the balancing weights, is
further simplified by a configuration in whic'h the receiver part and the other gripper unit are
displaceable relative to each other in the longitudinal direction of the rotor and both can
preferably be jointly displaced transversely 'to the longitudinal direction of (he rotor as the
receiver with the selected balancing weight and the counter element can thus be quickly
arranged opposite each other on the other gripper unit, '
A further advantageous configuration of the invention provides that preferably the lower
gripper unit comprises receivers for balancing weights arranged one behind ithe other and
transversely to the longitudinal direction of the rotor, with which receivers, in the gripper
closing direction, respective counter elements are associated in a corresponding number on
the other gripper unit. Aligned opposing counter elements are therefore associated with each
receiver and the selection and application of the selected balancing weight are possible by
simple joint displacement of the two gripper units transversely to the longitudinal axis of the
rotor without movable components being required for this.
Spot welding and projection welding can be used with a gripper-like device constructed as a welding device which comprises electrodes at both gripper units. Previously MIG and WIG welding were used for aluminium material but, in the meantime, projection welding of pre-shaped compensating sheets is also possible here.
A particularly simple method for applying the balancing weight provides that, in a gripper-like device comprising two gripper units, a plurality of balancing weights are received at preferably the lower gripper unit. These can be displaceably received via a receiver part for


the lower grippe)' unit or, instead, directly on the lower gripper unit such that they can only be
moved together therewith.

Counter elements, whose number equals thai of (he balancing weights, are provided on (he
upper gnpper unit in on the lower gripper
le application method of balancing weights non-displaceiibly arranged unit and the two gripper units are displaced jointly transversely to the longitudinal direction of the rotor and, after placement of the selected balancing weight, the weight and the associated opposing counter element is brought to rest on (he periphery of the rotor and fastened.
I In the application with displacement of the receiver part, the selected balancing weight is
placed on the upper gripper unit opposite a single counter element and fastened. With only
one row of balancing weights arranged on the receiver part transversely to the longitudinal
direction of the rotor, the receiver part is merely displaced on the lower gripper unit
transversely to the longitudinal direction of the rotor, wherein only the application process in
one compensation plane is observed.
If the balancing weights are provided in a plurality of rows, located one behind the other in the longitudinal direction of the rotor, in other words in a matrix-like manner on the receiving part at the lower gripper unit, then in an advantageous method the upper gripper unit, which does not cany any balancing weight, is not displaced on placement of the selected balancing weights, in other words is arranged opposite the balancing point. On placement of the selected balancing weight, the receiver part can be displaced transversely to the longitudinal direction of the rotor and in the longitudinal direction of the rotor. It may, however, also be provided that counter elements are arranged at the upper gripper unit in the transverse direction so as to correspond with the number of balancing weights lined up in a row of the lower gripper unit and subsequently a displacement of the receiver part in the longitudinal direction of the rotor on the lower gripper unit and a .common displacement of lower and upper gripper unit takes place in the transversa direction. Finally, an arrangement of counter
elements at the upper gripper unit in the longitudinal direction of the rotor in a number which
t
corresponds to thej number of rows of balancing weights located one behind the other at the
i
lower gripper unit is possible. In this ca|se the joint displacement takes place in the

i

longitudinal direction of the rotor and the displacement of the receiver part of the lower gripper unit in the transverse direction.
It is within the scope of the invention to provide the balancing weights on the upper gripper unit or on the upper and the lower gripper unit.
The invention will be described in more detail hereinafter with reference to-embodiments illustrated in the drawings, in which:
Fig. I is a side view of a device lor fastening balancing weights,
Fig. 2 is a front view of the device in Fig. 1,
Fig. 3 shows a portion of the device in Fig. 1,
Fig.4 shows a further embodiment of a portion of the device according to Fig. I.
r
Fig. 1 schematically shows a balancing machine 1 in wiich a balancing rotor 2 is mounted. The balancing machine 1 comprises bearing devices not' shown in greater detail for the rotor 2 to be balanced, at least one rotary drive, sensors for detecting the rotational behaviour of the rotor 2 and of imbalance-induced vibrations and an evaluation device for ascertaining the imbalance of the rotor 2. A device 3 for [fastening balancing weights in a plurality of
compensation planes of the rotor 2 is also arranged on the balancing machine 1.

In the x direction of a right angle coordinate system, as is symbolised in Fig. 2 by the double
arrow x, the device 3 ican be displaced on a guide rail 4 arranged on the frame of the
balancing machine !, along the axis of the rotor on which, in the illustration of Fig. 2, is
located in the plane of the page. The guide rail 4 spans the balancing machine in the
longitudinal direction of the rotor and is provided offset at the back, relative to the operator
side, from the rotor axis. The device 3 can thus be displaced on the guide rail' 4 in various
i
compensation planes and subsequently be arrested.

The device 3 can also be displaced in the y direction, transversely to the rotor axis, as indicated by the doublb arrow y in Fig. 2, in order to allow mounting of the rotor 2 in the
mounting devices of the balancing machine 1, or its removal. For mounting the rotor 2 or its
i
removal, the device 3 is displaced from the operator side toward the offset guide rail 4. To
allow fastening of balancing weights, the device 3 is returned in the direction of the rolor axis
after mounting of the rotor 2. ,
The device 3 comprises a gripper-like device 5 with which a balancing weight can be placed
in the respective compensation plane, on the external periphery of the rotor 2 and be fastened
i
there. The gripper-like device 5 incorporates, as can be seen in more detail from Fig. 3, and 4, two gripper units 6, 7, which are mounted in the gripper closing direction indicated by the double arrow z so as to float relative to each other, which, with the aid of an advancing unit 8, can be moved relative U> each oilier for increasing or reducing Iheir spacing.
For fastening the balancing weights, the gripper-like device 5 is arranged with its gripper units 6, 7 on either side of the rolor 2 so as lo partially surround il in such a way thai (In¬closing direction intersects the rotor axis. The gripper units 6, 7 arc jointly movable at the periphery of the rotor by means of an advancing unit 8, until they abut on one of the gripper units 6, 7, in the illustrated embodiment, until they abut on the upper gripper unit 6 on the rotor 2. As soon as the upper gripper unit 6 rests on the rolor 2, the lower gripper unit 7 is also brought into contact with the rotor 2 via the counterforce of the malvancing, unit 8 acting, on il. The movement of the lower gripper unit 7 is made possible here by a bearing of the gripper-like device 5, which bearing is floating in a gripper closing direction z on a carrier 12. To compensate for its weight, the gripper-like device 5 is supported here on the carrier 12 via a preferably pneumatic cylinder unit 9. The cylinder unit 9 is loaded with reduced pressure to compensate the weight. It can also be loaded at full pressure to raise the gripper-like device 3, when the rotor is not being used, to the extent that measuring bearing stands provided for
mounting the rotor can be overrun ip the x direction.
!
The lower gripper unit 7 is constructed to receive a plurality of balancing weights.
i

In the embodiment of Fig. 3 three receivers 7a, 7b and 7c are arranged one behind the other transversely to the longitudinal direction of (he rolor 2 and can be jointly displaced on the lower gripper unit 7 by means of an actuating device 11. The receivers 7a, 7b, 7c can be provided on the receiver part 10 for joint: displacement although the receivers 7a, 7b, 7c can also be displaceabie one behind the other in a guide profile. For application of the balancing weight, selected for this compensation plane, situated in the receiver 7c and which is adapted in this compensation plane in terms of form to the periphery of the rotor, the receivers 7a, 7b, 7c from the arrangement illustrated in Fig. 3, in which the receiver 7a is aligned with the rotor axis, are jointly displaced into the position illustrated in Fig. 1 in which the receiver 7c with the selected balancing weight is aligned with the rotor axis. The gripper-iike device 5 is accordingly moved in the closing direction until it abuts the upper gripper unit 6 on the rotor 2. The lower gripper unit 7 is then closed, the upper gripper unit 6 being used as a thrust bearing. The balancing weight in the receiver 7c is pressed against the periphery of the rolor and fastened to the rotor 2 by a welding process, the upper and the lower gripper units 6, 7 being used'as. electrodes. Once the gripper-iike device 5 has been opened, the device 3 is
moved into the next compensation plane and a further balancing weight is applied there,
l wherein prior to all application processes, the rotor 2 is rotated into the compensating angle
!
position for this compensation plane, ascertained during the- measuring phase. Once balancing
i weights have .been applied in all compensation planes, the device 3 is returned in the direction
of the guide rail 4, with the gripper-iike device 5, the rotor 2 is removed and a rotor not
subject to an imbalance is mounted in the balancing machine, the imbalance determined and
the compensation made as described above.
In the embodiment of the gripper-iike device 5 according to Fig. 4, three receivers 7a, 7b and 7c are arranged on the lower gripper unit 7 which cannot be displaced relative thereto. Three
counter elements 6a 6b and 6c on the upper gripper unit 6 are associated with the three
i
receivers 7a, 7b and 7c on the lower gripper unit 7 so as to be aligned in the gripper.'closing
t direction. For application of the balancing weight selected from the three balancing weights
for the respective compensation plane, for example of the balancing weight 7a for (he rotor
section with the smallest diameter illustrated in dot dash lines in Fig. 4, the entire gripper-iike
device 5 or the lower jtnd upper gripper units 6, 7 with the receivers 7a, 7b, 7c non-
displaceably arranged thereon and the counter elements 6a, 6b, 6c are displaced in such a way

that the rotor 2 is located with its axis aligned between the upper counter element 6 a and the lower receiver 7a. The application or welding process then takes place as described in more detail above.
In the described embodiments, the balancing weights are constructed as balancing metal
t sheets, of which the shape is adapted to the periphery of the rcrtor in the respective
1 compensation plane. Once a rotor 2 has been compensated], the gripper-like device 5 is moved
i to a loading station for equipping of the three receivers 7a, 7b,, 7c of the lower gripper unit 7
i
with balancing metal sheets which are to be used when the rotor is re-balanced. It goes
without saying, that,iif necessary, more than or fewer than three receivers, located one behind
the other, for balancing weights can be provide.
i \ In a modification to the development illustrated in Fig. 3, it can be provided, in a manner not
shown in greater detail, that further rows of, for example, three receivers are provided one
behind the1 other in the longitudinal direction of the rotor. This results overall in a matrix-like
arrangement of receivers, these expediently being arranged on a receiver part which can be
moved on the lower gripper unit. These receivers arranged on the receiver part w(hich can be
moved in the direction transverse to the longitudinal axis of the rotor and in. the longitudinal
direction of the rotor, can thus be equipped with balancing metal sheets such that, for
example, rotors with different shapes or different materials can be balanced in mixed
operation. For this purpose, the device is initially arranged in the desired compensation plane
and then, for example, the receiver part is moved in the longitudinal direction of the rotor in
accordance with the type of rotor to be balanced, until the respective row of three receivers of
the associated balancing metal sheet is located in the plane in which the counter clement of'
j the upper gripper unit is also located. Application of the balancing metal sheets selected from
this row of three takes place as described in more detail above with respect to Fig. 3, with
displacement of the receiver part on the lower gripper unit.
However, it may also be provided that a number of individual counter elements is provided on the upper gripper unit which corresponds to the number of rows of three on the lower gripper units, so, for application, merely a displacement of the receiver part on the lower gripper unit is required in the transverse direction, irrespective obviously of the movement in

the gripper closing direction and the displacement of the device into the respective i
compensation plane. It is also very easily possible with this configuration to carry out a correcting balance by means of a second supplementary imbalance compensating step which takes place in a compensation plane closely adjacent in the longitudinal direction of the rotor as only one further pair of counter clement and row of three is to be selected.
It also goes withput saying that, instead of or in addition to the illustrated and described welding device, other known fastening devices, such as gluing devices, may also be used.
It is within the scope of the invention to physically separate the device for fastening
balancing weights from the balancing machine if this proves to be advantageous, for
I example, for a production line. The rotor is then relocated from the balancing machine into
the device, wherein information on the ascertained imbalance or compensating data resulting
therefrom is pas'sed on.i


Documents:

705-mumnp-2004-abstract(21-02-2006).pdf

705-mumnp-2004-abstract(granted)-(21-02-2006).doc

705-mumnp-2004-cancelled pages (21-02-2006).pdf

705-mumnp-2004-claims(granted)-(21-02-2006).doc

705-mumnp-2004-claims(granted)-(21-02-2006).pdf

705-mumnp-2004-correspondence (21-02-2006).pdf

705-mumnp-2004-correspondence(ipo)-(28-02-2007).pdf

705-mumnp-2004-declaration(30-11-2004).pdf

705-mumnp-2004-drawing(21-02-2006).pdf

705-mumnp-2004-form 19(06-12-2004).pdf

705-mumnp-2004-form 1a(06-12-2004).pdf

705-mumnp-2004-form 2(granted)-(21-02-2006).doc

705-mumnp-2004-form 2(granted)-(21-02-2006).pdf

705-mumnp-2004-form 3(03-12-2004).pdf

705-mumnp-2004-form 5(03-12-2004).pdf

705-mumnp-2004-form-pct-isa-210 (21-02-2006).pdf

705-mumnp-2004-power of attorney(21-02-2006).pdf

abstract1.jpg


Patent Number 207885
Indian Patent Application Number 705/MUMNP/2004
PG Journal Number 42/2008
Publication Date 17-Oct-2008
Grant Date 29-Jun-2007
Date of Filing 06-Dec-2004
Name of Patentee SCHENCK ROTEC GMBH
Applicant Address LANDWEHRSTRASSE 55, D-64293, DARMSTADT,
Inventors:
# Inventor's Name Inventor's Address
1 HILLRINGHAUS FRANK IM KIRCHWALD 5, D- 64342 SEEHEIM,
2 ROGALLA, MARTIN SEEHEIMER STRASSE 90, D-64297 DARMSTADT,
PCT International Classification Number G01M
PCT International Application Number PCT/DEO3/02l80
PCT International Filing date 2003-07-01
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10230207.3 2002-07-04 Germany