FIELD OF THE INVENTION
The present invention relates to an apparatus for stacking laminations for
generator stator core upto a high height of the core by a programmable
manipulator.
BACKGROUND OF THE INVENTION
The laminations of a generator stator core are arranged in annular layers to form
packets. These packets of annular layers of laminations are axially spaced one
from the other by a special lamination having ventilation spacers for directing a
cooling flow radially thorough the stator.
The known method of assembly of the laminations is performed manually by
arranging the laminations in annular layers on a stationary circular table or a
rotating circular table (refer US Patent 6865797). The assembly is aided by
mandrels in the holes of laminations to align the laminations relative to each
other. The laminations are stacked at higher heights by a vertically moving
platform on which the operator is located or by carrying a partially assembled
stack using a lift plate (refer US Patent 6865797). In another method, referring
to US Patent 7946028, the laminations are stacked horizontally using keybar
extensions. In all the known method of assemblies, substantial and continuous
human effort and time is required.

OBJECTS OF THE INVENTION
It is therefore an object of the present invention to propose an apparatus for
stacking laminations for generator stator core using a vertically moving
programmable manipulator that can reach across the diameter and height of the
generator stator core with less human effort and time.
SUMMARY OF THE INVENTION
The present invention provides an apparatus for stacking laminations of a
generator stator core vertically using a programmable manipulator such as
articulated robot to form many annular layers of superimposed laminations and
particularly relates to the apparatus and method for stacking the laminations
vertically at higher heights with less human effort and time.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 is a perspective view of stacked laminations and packets showing
spacers between packets.
Figure 2 shows a programmable manipulator picking the lamination from a lower
stacking table.

Figure 3 shows the programmable manipulator of the lowest position on the
vertical slide column illustrating the placement of the lamination at a lower layer
on a circular assembly table.
Figure 4 shows the programmable manipulator at the top position on the vertical
slide column after placement of all the laminations at the pre-defined height.
DETAIL DESCRIPTION OF THE INVENTION
The present invention relates to an apparatus and a method and for stacking
laminations 1 and special laminations with ventilation spacers 2 of a generator
stator core in the form of annular layers 3, upto a high height of the core.
The embodiment of the present invention, the apparatus consists of a
programmable manipulator 4 mounted on a horizontal base plate 5 that travels
vertically on a vertical slide column 6, a gripper mounted at the end of the
programmable manipulator 7, a programmable controller for the manipulator
(not shown), a circular assembly table 8, lower lamination pickup tables 9 and
upper lamination pickup tables 10. The movement of the vertical slide 6, is
driven by one of hydraulic, pneumatic, electrical servo motor or any other
means, is linked to and causes an up and down movement of the horizontal
base plate 5 on which the programmable manipulator 4 is mounted.

In the embodiment of the present invention, the programmable manipulator 4
picks the laminations from the lower pickup table 9 or upper pickup table 10 by a
vacuum or electromagnetic gripper and disposes the picked-up lamination on the
circular assembly table 8 at a pre-defined programmed position to form an
annular layer. After completing one annular layer, the programmable manipulator
moves up on a vertical slide column 6 by a pre-defined programmed distance,
picks and places the laminations 1 for second and subsequent layers. Further,
special laminations having ventilation spacers (2) are picked from a separate
table (not shown) and disposed on the stacked lamination on the circular
assembly table 8 at pre-defined layer and position.
Depending on the relative position of the programmable manipulator and the
pickup tables, a program instructs the programmable manipulator 4 to pick up
laminations either from lower pickup table 9 or upper pickup table 10. As a
result, when the programmable manipulator reaches a certain height on a
vertical slide, it picks up the laminations from the upper pickup table 10 and
stacks the laminations on the upper annular layers of the generator stator core.

WE CLAIM:
1. An apparatus for stacking laminations to form annular layers of
superimposed laminations for use in generator stator core, comprising:
a programmable manipulator mounted on a horizontal slide plate that
travels vertically on a vertical slide column; a programmable controller for
controlling the manipulator; a gripper mounted at the end of the
manipulator; a circular assembly table; lower lamination pickup tables;
and upper lamination pickup tables, the movement of the vertical slide
provided by one of a mechanical, hydraulic, and electrical drive, the
apparatus is configured to :
(i) cause the manipulator to pick up laminations from the lower
and upper pickup tables by the gripper;
(ii) locate the pickup laminations on the circular assembly table at
predetermined position pre-set by the controller to form a
annular layer of laminations;
(iii) allow the manipulator to move vertically along the vertical slide
column upto a distance pre-set by the programmable
manipulator controller and arrange the layer of lamination upto
the maximum reachable diameter and height of the stator core;

(iv) pickup the lamination with ventilation spacers and disposing them
in between the stacked laminations; and
(v) repeat the activities at serial numbers (i) to (iv), wherein the
programmable manipulator is enabled to select one of the upper
pickup tables and the lower pickup tables for picking up the
laminations optimally, and further enabled to reach the maximum
height of the stator core for locating the laminations.
2. The apparatus as claimed in claim 1, wherein the superimposed
lamination are stacked automatically at the lower level and upper level
through a controlled program to eliminate manual errors and restrictions.