FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
AND
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2005
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
A testing equipment for testing commutators.
APPLICANTS
Crompton Greaves Limited, CG House, Dr Annie Besant Road, WorJi, Mumbai 400 030, Maharashtra, India, an Indian Company
INVENTORS
Kulkarni Raghvendra Krishnaji of Crompton Greaves Ltd, Alternator and DC Machines, LT Motor Division, A-6/2 MIDC, Ahmednagar, Maharashtra, India; an Indian National.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the nature of this invention and the manner in which it is to be performed:

Field of the Invention:
This invention relates to the fie electrical devices and testing equipment thereof.ld of
Particularly, this invention relates to a testing equipment for testing commutators.
Background of the Invention:
Commutators are an integral part of DC motors. It periodically reverses the current direction between the rotor and an external circuit.
Typically, a commutator consists of a metal cylindrical core with segmented vertical metal (copper) strips covering its circumference. There is provided an insulating material between said segmented metal (copper) strips and the metal cylindrical core. Further, the segmented vertical metal(copper) strips are placed that adjacent strips are spaced apart with respect to each other, and said spacing is filled with an insulating material. The insulating material may be mica.
In its operating configuration, the core conducts charge, and the metal strips conducts charge, too. For appropriate working conditions, it is necessary that the insulator performs the task of insulation, and there is no flashover current between the adjacent (segments) strips while current flows. Similarly, there should be no flashover current between the core and the strips.

Each commutator may consist hundreds of such strips. Thus, it is imperative that each strip be checked with respect to its adjacent strip to confirm non-conductance or flashover voltage, in its operative configuration. According to the prior art, this task of checking was performed manually, with a testing person utilizing two probes to individually check each pair of adjacent strips throughout the circumference of the commutator.
This process, besides being lengthy, was cumbersome, involved a lot of time, and does not warrant complete authenticated checking, as it is subject to manual processes.
There is a need to obviate these concerns.
Prior Art:
In light of the prior art US5637793, it is observed that the invention claimed the "chuck for supporting an electric motor armature.
In light of the prior art US5442953, it is observed that the invention disclosed the "commutator profiling system that includes a movable probe assembly.
However, there is a need for a comprehensive testing equipment for testing commutators.

Objects of the Invention:
An object of the invention is to fasten the process of testing commutators.
Another object of the invention is to automate the process of testing commutators.
Yet another object of the invention is to provide a reliable testing equipment for testing commutators.
Summary of the Invention:
For the purposes of the specification, a commutator comprises a metal core surrounded with vertical metal strips (segments), adjacent to each other,
According to this invention, there is provided a testing equipment for testing commutators with respect to adjacent segments and further with respect to core and said segments, said equipment comprising:
a. chuck means adapted to receive said commutator, co-axially, in its
operative horizontal configuration on said testing equipment;
b. jaws fitted onto said chuck means adapted to fit said commutator on
said testing equipment;
c. angular displacement means adapted to angularly displace said chuck
and said fitted commutator;
d. a pair of probes located on a stand corresponding to the operative
height of said commutator, said pair of probes carrying current, and
adapted to be placed on a pair of adjacent segments, respectively, for a

pre-defined instant to check for conductance and flashover voltage between said adjacent pair of probes;
e. sensing means adapted taid adjacent segments; and
f. marker means adapteo sense flashover voltage while said pair of
probes are placed over sd to mark said segment(s) upon sensing
flashover voltage in order to locate faulty insulation between
segments, thereby testing health of said commutator.
Preferably, said angular displacement means includes motor adapted to angularly displace said commutator.
Preferably, said angular displacement means includes stepper motor adapted to angularly displace said commutator in pre-defined steps.
Preferably, said angular displacement means includes control means adapted to define and control range of pre-defined steps for said angular displacement.
Alternatively, said equipment includes an insulated rod fitted in said chuck means and extending out of said chuck means in order to manually rotate said commutator.
According to an alternative embodiment of this invention, there is provided a testing equipment for testing commutators with respect to adjacent segments and further with respect to core and said segments, said equipment comprising:

a. chuck means adapted to receive said commutator, co-axially, in its
operative horizontal configuration on said testing equipment;
b. jaws fitted onto said chuck means adapted to fit said commutator on
said testing equipment;
c. angular displacement means adapted to angularly displace said chuck
and said fitted commutator;
d. a pair of probes comprising a first probe adapted to be placed on said
core and a second probe adapted to be placed on said segment to
check for conductance and flashover voltage between said core and
said segment;
e. sensing means adapted to sense flashover voltage while said pair of
probes are placed over said adjacent segments; and
f. marker means adapted to mark said segment(s) upon sensing
flashover voltage in order to locate faulty insulation between
segments, thereby testing health of said commutator.
Brief Description of the Accompanying Drawings:
The invention will now be described in relation to the accompanying drawings, in which:
Figure 1 illustrates a schematic of the testing equipment; and
Figure 2 illustrates a schematic of the testing equipment along with commutator installed on it.

Detailed Description of the Accompanying Drawings:
According to this invention, there is provided a testing equipment adapted to receive a commutator for testing commutators with respect to adjacent segments and further with respect to core and said segments. These tests check the health of the commutator,
Figure 1 illustrates a schematic of the testing equipment (100) in
accordance with this invention; and Figure 2 illustrates a schematic of the testing equipment, in accordance with this invention, along with commutator installed on it.
In accordance with an embodiment of this invention, there is provided a chuck means (10) adapted to receive said commutator (14), co-axially, in its operative horizontal configuration on said testing equipment. A commutator is brought and placed on said chuck means. This provides the resting position to cany out the tests. The chuck means is typically placed on a base means (11).
In accordance with another embodiment of this invention, there is provided a plurality of jaws (12) fitted onto said chuck means adapted to fit said commutator on said testing equipment.
In accordance with another embodiment of this invention, there is provided an angular displacement means adapted to angularly displace said chuck and said fitted commutator. The commutator may thus be rotated for purposes of testing. The angular displacement may be manual or automatic.

Preferably, a motor such as stepper motor may be attached to control angular displacement of said commutator. The stepper motor is defined to angularly displace the commutator in pre-defined steps i.e. covering a pre-defined arc over a pre-defined period of time with a pre-defined time interval between consequent angular displacements.
In accordance with yet another embodiment of this invention, there is provided a pair of probes (16, 18) located on a stand (19) corresponding to the operative height of said commutator, said pair of probes carrying current, and adapted to be placed on said segments for a brief period of time. Typically, a first probe is placed on a first segment. Typically, a second probe is simultaneously placed on a second segment As charge flows, through the probes and through the respective segments, it is checked that whether there is flashover or not.
In accordance with still another embodiment of this invention, there is provided a sensing means adapted to detect flashover voltage while said pair of probes are placed over said adjacent segments.
In accordance with an additional embodiment of this invention, there is provided a marker means (20) adapted to mark said segment(s) upon sensing flashover voltage in order to locate faulty insulation between segments, thereby testing health of said commutator. A plurality of marked segments may also be indicated.

In accordance with yet an additional embodiment of this invention, there is provided an insulated rod (22) fitted in said chuck means and extending out of said chuck means in order to manually rotate said commutator.
This action of marking or testing continues till the entire commutator is angularly displaced or until manual intervention takes place.

We claim,
1. A testing equipment for testing commutators with respect to adjacent segments and further with respect to core and said segments, said equipment comprising:
a. chuck means adapted to receive said commutator, co-axially, in its
operative horizontal configuration on said testing equipment;
b. jaws fitted onto said chuck means adapted to fit said commutator on
said testing equipment;
c. angular displacement means adapted to angularly displace said chuck
and said fitted commutator;
d. a pair of probes located on a stand corresponding to the operative
height of said commutator, said pair of probes carrying current, and
adapted to be placed on a pair of adjacent segments, respectively, for a
pre-defined instant to check for conductance and flashover voltage
between said adjacent pair of probes;
e. sensing means adapted to sense flashover voltage while said pair of
probes are placed over said adjacent segments; and
f. marker means adapted to mark said segment(s) upon sensing
flashover voltage in order to locate faulty insulation between
segments, thereby testing health of said commutator.
2. An equipment as claimed in claim 1 wherein, said angular displacement means includes motor adapted to angularly displace said commutator.

3. An equipment as claimed in claim 1 wherein, said angular displacement means includes stepper motor adapted to angularly displace said commutator in pre-defined steps.
4. An equipment as claimed in claim 3 wherein, said angular displacement means includes control means adapted to define and control range of predefined steps for said angular displacement.
5. An equipment as claimed in claim 1 wherein, said equipment includes an insulated rod fitted in said chuck means and extending out of said chuck means in order to manually rotate said commutator.
6. A testing equipment for testing commutators with respect to adjacent segments and further with respect to core and said segments, said equipment comprising:
a. chuck means adapted to receive said commutator, co-axially, in its
operative horizontal configuration on said testing equipment;
b. jaws fitted onto said chuck means adapted to fit said commutator on
said testing equipment;
c. angular displacement means adapted to angularly displace said chuck
and said fitted commutator;
d. a pair of probes comprising a first probe adapted to be placed on said
core and a second probe adapted to be placed on said segment to
check for conductance and flashover voltage between said core and
said segment;
e. sensing means adapted to sense flashover voltage while said pair of
probes are placed over said adjacent segments; and

f. marker means adapted to mark said segment(s) upon sensing flashover voltage in order to locate faulty insulation between segments, thereby testing health of said commutator.