FORM 2
The Patent Act 1970
(39 of 1970)
&
The Patent Rules  2005

COMPLETE SPECIFICATION
(SEE SECTION 10 AND RULE 13)

TITLE OF THE INVENTION

“Smart chip detector using a Reed switch”
APPLICANTS:
Name Nationality Address
Nallasani Pullaiah Naidu Indian HCL Technologies Ltd 
SEZ  TWR-
1 129  Jigani Industrial Area 
Bommasandra Jigani Link Road 
Bangalore – 562 106  Karnataka  (India)

Madhusudan R.S. Indian
HCL Technologies Ltd 
SEZ  TWR-
1 129  Jigani Industrial Area 
Bommasandra Jigani Link Road 
Bangalore – 562 106  Karnataka  (India)

The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed:-
FIELD OF INVENTION
[001] This invention relates to electronic sensors and detectors  and more particularly to a smart chip detector for sensing ferrous debris generated due to wear and tear in machines.
BACKGROUND OF INVENTION
[002] The failure mode of the bearings in aircraft gas turbine engines or the gears in helicopter gearboxes or aircraft or wind turbine  or steam turbine or earth moving heavy truck transmissions and other oil-wetted machinery is usually metal fatigue. At the onset of failure  tiny metal flakes or chips or debris are produced which are carried away by the lubricating oil. The debris in close loop oil system slowly affects the performance of machines  if ignored  catastrophic failure of components can occur. Debris is typically carried by the engine’s lubricating oil toward a sump or a filter. The debris is generally detected by using a magnet based device also called as chip detectors or electric chip detectors (ECD). The chip detectors collect debris and can provide an alerting signal mechanism if it exceeds a threshold.
[003] There are several chip detector devices available in the market. They may use inductive  magnetic or other means for wear debris detection. The performance of these chip detectors may be checked/verified only during periodic maintenance or after any incident. These chip detectors do not have means to check self-performance and do not possess a mechanism to raise an alert if there is an error in the detector device or if the detector device is unable to perform its tasks adequately. Hence  a component may fail or perform below standards due to a faulty chip detector and this would not be found until maintenance is done. Hence the ability to detect these chips and condition of sensor while the aircraft or equipment in working state i.e. the nascent state of failure  will enable the ground crew or maintenance personal to route the aircraft or the machines to a scheduled maintenance facility for repair.

OBJECT OF INVENTION
[004] The principal object of any chip detector is alerting the presence of wear related debris in machine  as in prior art.
[005] The object of this invention is to ensure that the smart chip detector can perform a self-check to detect weather its working or not. If the sensor is not working as in prior art there will be no alarm  which may be wrongly taken as safe operating condition.

STATEMENT OF INVENTION
[006] Accordingly the invention provides an apparatus comprising of reed element which is characterized such that there is a smart chip detector so as to detect the working condition of the magnet.
[007] Disclosed herein is a system for detecting deterioration in magnetic strength of at least one magnet  the smart chip detector comprising a reed switch present in vicinity of the at least one magnet  wherein the reed switch is configured to switch to state 2 when the magnetic strength is below a threshold; a detector to detect when the reed switch is in state 2; and an alerting system to indicate that the magnetic strength has reduced below a threshold  on receiving an alert from the detector.
[008] Embodiments herein also disclose a method for detecting deterioration in magnetic strength of at least one magnet using a smart chip detector  the method comprising of comparing the magnetic strength to a threshold by a reed switch; and raising an alert if the magnetic strength is below the threshold by an alerting system.
[009] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood  however  that the following descriptions  while indicating preferred embodiments and numerous specific details thereof  are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof  and the embodiments herein include all such modifications.

BRIEF DESCRIPTION OF FIGURES
[010] This invention is illustrated in the accompanying drawings  throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings  in which:
[011] FIG. 1 illustrates the block diagram of a broad smart chip detector system  according to the embodiments as disclosed herein;
[012] FIG. 2 shows the front view of a smart chip detector constructed according to the embodiments as disclosed herein;
[013] FIG. 3 is a block diagram showing various processing blocks of a smart chip detector  according to the embodiments disclosed herein;
[014] FIG. 4 is a table showing some of the various scenarios where magnet deterioration takes place  according to the embodiments disclosed herein; and
[015] FIG. 5 is a flowchart showing the method of operation of the smart chip detector  according to embodiments disclosed herein.

DETAILED DESCRIPTION OF INVENTION
[016] The embodiments herein  the various features  and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly  the examples should not be construed as limiting the scope of the embodiments herein.
[017] Referring now to the drawings  and more particularly to FIGS. 1 through 5  where similar reference characters denote corresponding features consistently throughout the figures  there are shown preferred embodiments.
[018] FIG. 1 illustrates the block diagram of a broad smart chip detector system  according to the embodiments as disclosed herein. The block diagram shows the magnetic health alarm 101  the reed switch 104  the magnet 102 and the chip gap 103. The smart chip detector containing the reed switch 104 is placed in the magnetic field 202. The magnet 102 may be a single annular magnet or comprise of a plurality of magnets. The magnet 102 may also be a permanent magnet or an electro magnet. The magnets 102 may also comprise of a combination of permanent magnets and electro magnets. The magnet 102 is used for producing a magnetic field in any machine fluid. The machine fluid may be oil or any other fluid used in machines. A set of contacts connect the reed switch 104 to the magnetic health alarm indictor 101. As particles accumulate near the contacts and bridges the chip gap 103 of the magnet 102  the magnetic field is redistributed. This continuity of circuit gives an indication of particle accumulation. A reed switch is an electrical switch operated by an applied magnetic field. The reed switch 104 may be a Single Pole Single Throw (SPST) reed switch  a Single Pole Double Throw (SPDT) or any other suitable type of reed switch. Based on the changes in the magnetic field  the reed switch 104 changes its state. When the magnetic field produced by the magnets 102 is high  the reed switch 104 remains in its state 1. When the strength of the magnetic field reduces below a specified threshold  the reed switch 104 changes from state 1 to state 2. The reduction in the strength of the magnetic field may be caused due to redistribution of the magnetic field due to accumulation of debris. The reduction in the strength of the magnetic field may also be due to other reasons such as magnetic field weakening over time due to natural/external causes. The amount of reduction in magnetic field to make the reed switch 106 change from state 1 to state 2 can be set in the smart chip detector. The selection of reed switch is based on the size and power of the magnet  distance between the reed switch and magnet  stiffness of the reed switch and the design of the smart chip detector.
[019] FIG. 2 shows the front view of a smart chip detector constructed according to the embodiments as disclosed herein. The smart chip detector 200 contains permanent magnet 102 which produces a magnetic field 202 around the reed switch 104. The presence of debris particles in the machine liquid slowly build up near the electrical contacts 104 of the permanent magnet 102  creating a circuit like the one shown in figure 1. The magnetic field 202 changes due to the presence of the particles. The contact wires 201 of the reed switch 104 connect to a processor (not shown in the figure). The reed switch 104 measures changes in the magnetic field 202. The reed switch 104 changes states based on the changes in the magnetic field 202. When the strength of the magnetic field 202 produced by the magnet102 is high  the reed switch remains in a state1. When the strength of the magnetic field reduces below a specified threshold  the reed switch 106 changes from state 1 to state 2. The reduction in the strength of the magnetic field may be caused due to redistribution of the magnetic field due to accumulation of debris. The reduction in the strength of the magnetic field may be due to other reasons such as magnetic field weakening over time due to natural/external causes. The amount of reduction in magnetic field to make the reed switch 104 change from state 1 to state 2 can be set in the processor of the smart chip detector.
[020] FIG. 3 is a block diagram showing various processing blocks of a smart chip detector  according to the embodiments disclosed herein. This block diagram shows components of the processor 301 relevant to the present invention and do not describe all the components of a smart detector chip. The analog to digital convertor –ADC 302 convert""s analog values measured into digital values. The processor 301contains various blocks. A comparator 303 is used to compare measured values with threshold levels defined in the processor. The sensitive controller 304 defines the magnetic field 202 values at which the reed switch 104 should be in state 2. As the ferrous particle  accumulation continues and an electrical connection is formed between the magnets 102  the magnetic field 202 keeps changing. The apparent reduction in the strength of the magnetic field may be caused due to redistribution of the magnetic field due to accumulation of debris. The reduction in the strength of the magnetic field may also be due to other reasons such as magnetic field weakening over time due to natural/external causes. Based on the changes in the magnetic field 202  the processor 301 can activate the magnetic health alarm 101  which indicates the poor condition of the magnets 102. In case where the smart chip detector is a part of a controlled system an alarm inform of an audible of visual beep can be seen on the computer screen of operator controlling the system. If the smart chip detector is not connected to control system an alarm device may be connected. This alarm device may be a siren with visual blinking light and selectable alarm tones.
[021] FIG. 4 is a table showing some of the various scenarios where magnet deterioration takes place  according to the embodiments disclosed herein. The table classifies different types of condition and the related reed switch 106 activity. In type 1 condition  when a smart chip sensor encounter ferrous particles in fluid and no magnet deterioration  the reed switch 104 does not actuate and the magnet health alarm does not. There can be a situation where there might be heavy accumulation of particles around the magnet or accumulation is not symmetric around the magnet. In both of these situations chip accumulation as well magnet deterioration alarm will trigger. In this case magnet health alarm can be ignored or electronically suppressed as the particles are attracted to the magnet. The type 2 presents a condition where presence of debris particle in the fluid and magnet deterioration. Here as there is magnet deterioration there will be no alarm for article accumulation. In this condition  the reed switch 104 actuates the magnetic health alarm 101. The type 3 presents a condition when there are no debris particles in fluid but the magnetic health is poor. In this scenario  the reed switch 104 actuates and the magnetic health alarm 101 is activated. The type 4 shows a normal operating condition where there is no debris in fluid and magnetic deterioration is under normal ranges and there is no need for activating the alarm.
[022] FIG. 5 is a flowchart showing the method of operation of the smart chip detector  according to embodiments disclosed herein. The method begins with the processor checking (501) if the reed switch 104 is state 2. If the reed switch 104 is not state 2  the processor goes back to the step 501. If the reed switch 104 is state 2  an alert signal is sent (502) to the magnetic health alarm 101. The magnetic health alarm 101 produces (503) an audible or visual alarm alerting deterioration of the magnet 102. The various actions in method above may be performed in the order presented  in a different order or simultaneously. Further  in some embodiments  some actions listed in Figures 5 may be omitted.
[023] Though the above embodiments describe monitoring strength of a single magnet  it may be obvious to a person of ordinary skill in the art to use the reed switch as described above to monitor the strength of a plurality of magnets.
[024] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can  by applying current knowledge  readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept  and  therefore  such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore  while the embodiments herein have been described in terms of preferred embodiments  those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.

STATEMENT OF CLAIMS
1. A system for detecting deterioration in magnetic strength of at least one magnet  said smart chip detector comprising:
a reed switch present in vicinity of said at least one magnet  wherein said reed switch is configured to switch to state 2 when said magnetic strength is below a threshold;
a detector to detect when said reed switch is in state 2; and
an alerting system to indicate that said magnetic strength has reduced below a threshold  on receiving an alert from said detector.

2. The system  as claimed in claim 1  where said reed switch is at least one of a
A Single Pole Single Throw reed switch; or
A Single Pole Double Throw reed switch.

3. The system  as claimed in claim 1  where said at least one magnet is at least one of a
At least one permanent magnet;
At least one electro magnet; or
A combination of permanent magnets and electro magnets.

4. The system  as claimed in claim 1  where said magnetic strength changes with at least one of
ferrous particle accumulation on said at least one magnet; and
deterioration of performance of said at least one magnet.

5. The system  as claimed in claim 1  wherein said detector further comprises of at least one means configured for sending an indication to said alerting system on detecting that said reed switch is in state 2.

6. The system  as claimed in claim 1  wherein said alerting system is at least one of
A visual alerting system;
An audio based alerting system; and
A combination of a visual and audio based alerting system.

7. A method for detecting deterioration in magnetic strength of at least one magnet using a smart chip detector  said method comprising of:
Comparing said magnetic strength to a threshold by a reed switch; and
Raising an alert if said magnetic strength is below said threshold by an alerting system.

8. The method  as claimed in claim 6  where said reed switch is least one of a
A Single Pole Single Throw reed switch; or
A Single Pole Double Throw reed switch.

9. The method  as claimed in claim 6  wherein said reed switch moves to state 2  if said magnetic strength is below said threshold.

10. The method  as claimed in claim 6  where said magnetic strength changes with at least one of
ferrous particle accumulation on said at least one magnet; and
deterioration of performance of said at least one magnet.

11. The method  as claimed in claim 6  wherein said alerting system is at least one of
A visual alerting system;
An audio based alerting system; and
A combination of a visual and audio based alerting system.

Dated this 16th September 2011

Dr. Kalyan Chakravarthy
Patent Agent.
ABSTRACT

The fluid monitoring sensor Electrical Chip Detector (ECD) used in fluid circuit to separate ferrous particles. Basically it constitutes two components  one is the sensor probe another is self closing valve. The detectors are intrusive type working in recirculation oil under harsh conditions. The magnets are subjected to synthetic oils and the operating temperature can go up to 185°C. The sensor can become ineffective if the magnet loses its strength. As per this new invention the health of the sensor can be monitored by either by introducing a Reed element positioned in proximity to magnet. This will ensure the operational effectiveness of the sensor and makes the ECD as smart chip detector.
FIG. 2