Line replaceable unit (LRU) sensor systems for motors and other machines

A motor has a housing which comprises a cavity and a socket accessible from outside the housing. The socket has an interior surface. The motor includes a LRU sensor system which comprises an LRU sensor having electrical conductors and internal sensor wiring that is electrically connected to the electrical conductors and electrical conductors on the interior surface of the socket, wherein when the LRU sensor is positioned in the socket, the electrical conductors on the LRU sensor contact the electrical conductors on the interior surface of the socket.

TECHNICAL FIELD

The present invention generally relates to sensor systems for machines, including but not limited to motors, compressors, generators, turbines and pumps.

BACKGROUND ART

Cooling towers utilize relatively large motors to rotate the cooling tower fan. The cooling tower fans are of various sizes but can have diameters as large as forty feet. The health of the motor is vital to the efficient and safe operation of the cooling tower. Motor sensors are used to provide information about motor health and the components that they drive, such as vibrations, bearing wear or heat within the motor housing or casing. Sensors are also used to provide information about the exterior motor temperature. Some sensors on the motor can measure the vibrations of the cooling tower fans. This feature is especially useful in preventing damage to the cooling tower structure cause by fan imbalance and failed fan blades. Air flow sensors can be used to measure the flow of air produced by the rotation of the cooling tower fan. Other sensors used in cooling towers include, but are not limited to, pressure sensors, displacement sensors, gas monitor sensors, infrared sensors, encoders, optical encoders, and position, speed and mechanical load sensors. Most all sensors require a communication cable in electronic signal communication with the sensor. The sensor outputs a signal, such as an electrical voltage, which may be inputted into another device, such as a signal conditioner. The signal conditioner processes and decodes the sensor signal so as to yield a signal that represents temperature, vibration or force. These signals may then be inputted into other components such as electronically commutated motors, variable frequency drives (VFD) variable speed device (VSD) or an industrial computer. Thus, the sensor signals can be used as part of a feedback scheme that controls the operation of the motor and the safety and efficiency of the driven system.

Some sensors require power, or an input voltage or some type of input communications signal. These types of sensors are typically used with communication cables that have multiple terminals at the wire-connector end in order to provide and receive these various power and communications signals to and from, respectively, the sensor. Such sensors, wires and communication cables are typically configured for relatively low voltage and current with relatively small gauge wires. These communication cables typically have internal shielding and are easily routed on the exterior of the motor. Communication cables, however, frequently break and corrode. Furthermore, a broken communication cable can spark and cause a fire or explosion in a hazardous environment such as a cooling tower. One attempt to solve these problems is to run the communication cable in a protective conduit or cable gland. However, even when the communication cables are within conduits or cable glands, the communication cables still experience corrosion and contamination when these communication cables are used in wet, harsh environments such as wet cooling towers. This corrosion and contamination make it difficult to separate electrical connectors when external motor sensors need to be replace thereby requiring cables, leads and conduit to be replaced. Such maintenance necessitates shutting down the cooling tower resulting in reduced production and increased maintenance costs. Another attempt to solve the problems associated with corrosion and contamination is to build the sensors into the frame work of the motor. This is typically done for temperature sensors such as RTD sensors and Thermocouple sensors. However, over time, these RTD and Thermocouple sensors have a less-than-desirable MTBF and cannot be replaced in the field. RTD and Thermocouple sensors are typically replaced when the motor is being re-wound and overhauled at a motor repair facility. Furthermore, if the sensor is mission critical, such as a vibration sensor, the motor may have to be replaced in order to comply with OSHA safety regulations.

What is need is a sensor system that substantially eliminates the foregoing problems and disadvantages associated with prior art motor sensor systems.

DISCLOSURE OF THE INVENTION

In one aspect, the present invention is directed to Line Replaceable Unit (LRU) sensor systems for use with motors that monitor and supervise various parameters of the motor and the safe and efficient operation of their driven systems, including but not limited to, vibrations and temperature. The LRU sensor is comprised of sensors that are installed within the protection of the motor cavity and utilize internal Wireways within the motor for power, communication and grounding. These wireways all connect at a common point or junction box within the motor cavity that allows for at least one single quick-disconnect at the motor casing for ease of connecting outside power and communication to the motor for safe and efficient operation.

Even though each sensor could be wired individually by an electrician utilizing wires internal or external to the motor, in the preferred embodiment, the LRU sensors are configured for “plug and play” installation, eliminating the need for wiring and a skilled electrician to perform the task. In this preferred embodiment, the sensors are installed similar to a light bulb where the bulb is screwed into a powered socket and connected internally within the socket to electrical power without any wires required to be connected, grounded or terminated. The installation of these LRU sensors is similar to a USB Flash Drive which is connected to a corresponding USB port and draws power from the port to operate the USB Flash Drive.

The sensors of the LRU sensor systems can easily be replaced in the field by maintenance mechanics using common hand tools. The maintenance mechanics do not need special training to replace the sensors. The sensors of the LRU sensor systems are replaced without having to move or remove the motor thereby allowing maintenance mechanics to return the motor to safe operation in a minimal amount of time.

A significant advantage of the LRU sensor systems of the present invention is that all power and communication wiring of the LRU sensor system is routed within the interior or cavity of the motor thereby protecting the power and communication wiring from impact damage, corrosion and contamination.

Significant benefits of the LRU sensor systems of the present invention are the elimination of the complex prior art communication cable and gland system and the need for an electrician to service the aforesaid communication cable and gland system.

Another benefit of the LRU sensor systems of the present invention is that, since the sensors, communication cables and other associated wiring are located within the interior or cavity of a sealed motor, the sensors, cables and wires are isolated from explosive or hazardous environments thereby eliminating the risk of fire or explosions commonly associated with defective or compromised prior art external conduit systems.

Another benefit is that commercially available current art sensors may be adapted for use in the LRU sensor systems of the present invention.

Other benefits of the LRU sensor systems of the present invention are improved reliability, production, safety, plug-and-play capability and reduced need for skilled labor.

The LRU sensor systems can also be used with other machinery, including but not limited to, pumps, compressors, turbines and other mission critical machinery.

In some embodiments, the LRU sensor system is used with a sealed motor wherein the sealed motor has in the cavity thereof a sensor power source for powering the LRU sensor, an amplifier for amplifying LRU sensor output signals and a condition monitoring device. In another embodiment, the sensor power source, amplifier and condition monitoring device are located on the sealed motor. In a further embodiment, the sensor power source, amplifier and condition monitoring device are located about the sealed motor.

BEST MODE FOR CARRYING OUT THE INVENTION

As used herein, the term “motor” shall mean any electric motor with a rotor and stator that creates flux.

As used herein, the terms “casing” and “housing” are used interchangeably and shall have the same meaning and include casings or housings for motors, pumps, compressors, turbines, turbomachinery, and generators. In the case of motors, the terms “casing” and “housing” shall include the top and bottom covers of the motor.

As used herein, terms “cavity” and “interior” shall mean the interior of the casing or housing.

Although the ensuing description is in terms of the LRU sensor systems of the present invention being used with motors, it is to be understood that the LRU sensor systems can be used in other types of machinery, including but not limited to generators, compressors, pumps, turbines, turbomachinery and turbines.

It to be understood that the LRU sensors described herein can be configured to sense vibrations, temperature, heat, airflow, moisture, humidity, harmful or toxic gases or fumes and bacteria, including legionella.

It is also to be understood that the LRU sensors described herein may be configured as wireless sensors, photonic sensors, infrared sensors, optical sensors, fiber optic sensors, optical encoder sensors and radio-frequency (RF) sensors.

FIGS. 1A-1Jshow different embodiments of terminal pairs that maybe used in the LRU sensor systems of the present invention. In a preferred embodiment, a terminal pair discretely connects only one of the following: (a) electrical current, (b) electrical ground or (c) communication signals. However, in alternate embodiments, a terminal pair discretely connects electrical power and at least one communication signal.

Referring toFIG. 1A, there is shown a pair of raised terminals10and12that are similar to battery terminals in a common flashlight. Terminal10is part of LRU sensor20. LRU sensor20includes wiring22that is electrically connected to terminal10. Terminal12is at a particular location on motor housing or casing30such as within a socket or female receptacle formed in the motor housing or casing30. Wiring14is electrically connected to terminal12and a wiring network (not shown) that is located within the interior or cavity of the motor. When terminal10and terminal12contact each other, a closed electrical circuit is created such that the wiring network inside the motor housing30is electrically connected to the wiring of LRU sensor20. This closed electrical circuit forms an electrical path for electrical current, electrical ground or communication signals.

In one embodiment, the motor housing30has a socket or female receptacle and at least one raised terminal12located within the socket or female receptacle. When the LRU sensor20is positioned within the socket or female receptacle, terminal10contacts terminal12. In an alternate embodiment, either or both terminals10and12are spring loaded to ensure positive and firm engagement.

Referring toFIG. 1B, shows a receptacle-terminal pair comprising female receptacle50and male terminal52. Wiring54is electrically connected to female receptacle50. Wiring56is electrically connected to male terminal52. Female receptacle50is part of assembly60which can be either an LRU sensor or a motor housing. Male terminal52is part of assembly62which can be either an LRU sensor or the motor housing. In one embodiment, assembly60is a motor housing, female receptacle50is located within a socket or female receptacle formed in the motor housing and assembly62is an LRU sensor having male terminal pin52. Wiring54is electrically connected to the internal wiring network inside the motor cavity. When male terminal pin52is inserted into and contacts female receptacle50, a closed electrical circuit is created comprising the LRU sensor62, wiring56, male terminal pin52, female receptacle50, wiring54and the wiring network in the motor interior. This closed electrical circuit forms an electrical path for electrical current, electrical ground or communication signals.

In an alternate embodiment, male terminal52is spring-loaded to ensure positive and firm engagement with female receptacle50.

Referring toFIG. 1C, there is shown a terminal pair that comprises terminal pin70and raised terminal72. Terminal pin70includes wiring74. Wiring74is electrically connected to terminal pin70. Terminal pin70is part of assembly76which, in one embodiment, is an LRU sensor in accordance with the invention. Raised terminal72includes wiring78. Wiring78is electrically connected to raised terminal72. Raised terminal72is part of assembly80which, in one embodiment, is the housing or casing or a motor. The motor includes an internal wiring network in the motor interior or cavity. Wiring78is electrically connected to the aforementioned internal wiring network. When terminal pin70and raised terminal72contact each other, a closed electrical circuit is created which comprises wiring78, raised terminal72, terminal pin70and wiring74such that the internal wiring network inside the motor is now in electronic signal communication with the LRU sensor. This closed electrical circuit forms an electrical path for electrical current, electrical ground or communication signals.

In one embodiment, terminal pin70is spring-loaded to ensure firm and positive engagement with raised terminal72.

An advantage of raised terminal72is that if raised terminal72is located at the bottom of a socket or female receptacle in a motor housing and foreign particles or contaminants collected in the socket, raised terminal72would protrude above the layer of foreign particles or contaminants.

Referring toFIG. 1D, there is shown another terminal pin and female receptacle combination. Terminal pin90includes wiring94and is part of assembly98which, in one embodiment, is an LRU sensor in accordance with the invention. Terminal pin90has a rounded tip100. Female receptacle102includes wiring104and is part of assembly106which, in one embodiment, is the casing of a motor. The motor includes an internal wiring network in the cavity of the motor and wiring104is electrically connected to the internal wiring network. Rounded tip100is shaped and configured so as to fit into female receptacle102. When rounded tip100of pin terminal90is positioned within female receptacle102, a closed electrical circuit is created such that the internal wiring network inside the motor is electrically connected to wiring104, female receptacle102, terminal pin90, wiring94and the LRU sensor. This closed electrical circuit forms an electrical path for electrical current, electrical ground or communication signals.

In an alternate embodiment, terminal pin90is spring-loaded to ensure firm and positive engagement with female receptacle102.

Referring toFIG. 1E, there is shown another terminal pin and female receptacle combination in accordance with the invention. In this embodiment, the terminal pin engages the female receptacle similar to the way mating DIN connectors are engaged together. DIN connectors are well known in the art and are therefore not discussed herein. Terminal pin120has the same configuration as terminal pin70shown inFIG. 1C. Terminal pin120includes wiring122. Wiring122is electrically connected to terminal pin120. Terminal pin120is part of assembly124which, in one embodiment, is an LRU sensor in accordance with the invention. In this embodiment, female receptacle122is configured as a sleeve. Sleeve122is sized to receive terminal pin120. Wiring126is electrically conducted to sleeve122. Sleeve122is located in the casing of a motor. Sleeve122can be formed during the manufacture of the casing. The motor has an internal wiring network and wiring126is electrically connected to the internal wiring network. When terminal pin120is disposed within sleeve122, a closed electrical circuit is formed in which creates an electrical path for electrical current, electrical ground or communication signals.

In a preferred embodiment, terminal pin120and sleeve122are sized so that there is an interference fit between terminal pin120and sleeve122in order to improve the integrity of the electrical connection.

In one embodiment, wiper130positioned at the entrance of sleeve122. Wiper130creates the same effect as an interference fit. As terminal pin120is pushed through this area and into sleeve122, wiper130scrapes the exterior surface of terminal pin120so as to remove dirt, grime, oxidation and other foreign particles. Wiper130actually scratches the exterior surface of terminal pin120thereby providing a clean surface that contacts sleeve122to create a high-integrity electrical connection between terminal pin120and sleeve122. Wipers may be configured to have any shape or design, depending upon the application. Wiper structures are well known in the art and are therefore not discussed in detail herein.

In an alternate embodiment, an auxiliary seal is added to the entrance of sleeve122. In a further embodiment, a wiper gasket encloses the opening of sleeve122when the terminal pin120is withdrawn from sleeve122so as to prevent dirt, moisture and foreign particles from entering sleeve122.

Referring toFIG. 1F, which is similar to a common household appliance plug and outlet, there is shown another embodiment of a scheme for electrically connecting an LRU sensor to a socket or female receptacle in a motor casing. In this embodiment, terminal150comprises a terminal spade. Terminal spade150is part of an LRU sensor. Terminal spade150is sized for an interference fit within female receptacle or socket154. Socket154includes wiring or conductor156which is electrically connected to an internal wiring network inside the motor cavity that may electrically connect power, communication or provide grounding.

In an alternate embodiment, an auxiliary seal or gasket is used at the entrance to female receptacle154. In a further embodiment, wiper158is used at the entrance to female receptacle154and is configured for an interference fit with the interior of female receptacle154. As terminal pin150is pushed into female receptacle154, wiper158cleans and scrapes terminal pin150so as to improve the integrity of the electrical connection between terminal pin150and female receptacle154.

Referring toFIG. 1G, there is shown electrically conductive strip200that is used with a plurality of terminals pins202,204and206. Each terminal pin202,204and206is part of a corresponding LRU sensor. In this embodiment, each terminal pin202,204and206is a raised terminal pin. The electrically conductive strip200is similar in construction to the power strip described in U.S. Pat. No. 8,894,296, entitled “Powered CAT 5 Plug and Socket”, the disclosure of which patent is incorporated by reference. The electrically conductive strip200may be used as a power strip or grounding strip, or may be used to deliver communication signals to the LRU sensors. For example, electrically conductive strip200may be used as a power strip to provide power or electrical ground to the plurality of terminals pins202,204and206. Although three terminal pins202,204and206are shown inFIG. 1G, it is to be understood that electrically conductive strip200may be used with fewer than three terminal pins or more than three terminal pins. In one embodiment, electrically conductive strip200may be applied to the inner surface of a female receptacle or socket and each raised terminal pin202may be part of an LRU sensor. In another embodiment, one or more electrically conductive strips200are attached, joined or formed on the exterior surface of an LRU sensor. This embodiment is illustrated inFIG. 1H. Cylindrically shaped LRU sensor210is located within socket220. Socket220is located in the casing or housing221of a motor or other machine. Electrically conductive strips211and212are attached to the exterior surface of LRU sensor210and are applied to the entire circumference or perimeter of the LRU. Electrically conductive strips211and212are identical in construction to electrically conductive strip200shown inFIG. 1G. LRU sensor210includes recess224. Recess224is sized to receive a tool for removing LRU sensor210from socket220or inserting LRU sensor210into socket220. Socket220has an inner surface222. Raised terminal pins300,302,304and306are attached or joined to inner surface222. When LRU sensor210is completely inserted into socket220, electrically conductive strip211contacts raised terminal pins300and302and electrically conductive strip212contacts raised terminal pins304and306. Raised terminal pins300,302,304and306are electrically connected to an internal wiring network that inside the motor cavity. LRU sensor210is completely accessible from outside the motor casing221and thus can be replaced without having to access the cavity of the motor.

Referring toFIG. 1I, there is shown an LRU sensor system that uses the raised terminal pin embodiment shown inFIG. 1Aherein. Motor350comprises casing352. Casing352has socket354which has an inner surface356. Raised terminal pins358,360,362and364are attached or joined to inner surface356. Wires or electrically conductive members366,368,370and372are electrically connected to raised terminal pins358,360,362and364, respectively, and to an internal wiring network inside the cavity of motor350. LRU sensor380is positioned in socket354and includes raised terminal pins382,384,386and388. The raised terminal terminals382,384,386and388contact the raised terminal pins358,360,362and364, respectively. Raised terminal terminals382,384,386and388are electrically connected to internal wiring and circuitry of LRU sensor380. LRU sensor380includes recess390that is sized to receive a tool (e.g. hex drive) which can be used to insert LRU sensor380into socket354or remove LRU sensor380from socket354. As shown inFIG. 1I, LRU sensor380does not protrude above the exterior surface of casing352. In such an embodiment, a cover can be removably attached to casing352. A gasket or seal can be disposed between the cover and casing352in order to prevent moisture and foreign particles from entering socket354. LRU sensor380is completely accessible from outside the motor casing352and thus can be replaced without having to access the cavity of the motor.

Referring toFIG. 1J, there is shown electrically conductive land300that is configured to contact a plurality of terminal pins302,304,306and308and form an electrical connection with these terminal pins. Each terminal pin302,304,306and308can be part of a separate LRU sensor. Land300can be used to provide electrical power or ground to terminal pins302,304,306and308. In other embodiments, a plurality of electrically conductive lands, identical in structure to land300, can be used with the plurality of terminal pins wherein each electrically conductive land contacts only particular terminal pins. Each electrically conductive land may have a different function. For example, a first electrically conductive land provides electrical power, a second electrically conductive land provides electrical ground and to each terminal pin, and a third electrically conductive land provides a signal path for sensor output signals. Each electrically conductive land can be electrically connected to the internal wiring network inside the motor.

In all of the embodiments and configurations disclosed herein, the LRU sensor systems of the present invention may be realized and implemented without any regard to orientation of the LRU sensor. Therefore, the LRU sensor systems will function properly no matter if the LRU sensor is right-side up, upside down, sideways or angulated.

In one embodiment, the LRU sensor systems are configured such that the LRU sensors are removably secured to a motor by a “push and twist lock” or “insert, rotate and lock” features which are described below. In another embodiment, the LRU sensors are removably secured to a motor by an “indexed screw” feature. In a further embodiment, and as discussed in the foregoing description, the LRU sensor is interference fitted into the socket or female receptacle in the motor housing or casing.

The surface area, size, geometry, insulation, location and orientation of the aforementioned male terminals and corresponding sockets or female receptacles may be varied depending upon the particular application, the type of motor and the environment in which the LRU sensor system will be operating.

Referring toFIG. 2A, there is shown LRU piezoelectric sensor400that is used in an LRU sensor system in accordance with one embodiment of the invention. In this embodiment, LRU piezoelectric sensor400is a vibration sensor. LRU piezoelectric sensor400comprises housing402and interior region or space404. Housing402has exterior surface405. LRU piezoelectric sensor400further comprises piezoelectric element406and double-ended mass-spring element408which are located within interior region or space404. LRU piezoelectric sensor400also includes an additional mass410within interior space404. Housing402has top end412, bottom end414and threaded portion416. Threaded portion416is configured to be screwed into complementary mating threads of a socket or female receptacle. The structure for the LRU piezoelectric sensor400as described so far can be realized any one of a variety of commercially available vibration sensors. In accordance with the invention, LRU piezoelectric sensor400is configured to have raised terminals420and430. Raised terminals420and430are electrically connected to the internal wiring (not shown) of LRU sensor400. Terminal420is attached or joined to exterior surface405housing402. Terminal430is attached or joined to bottom portion414of housing402. Terminals420and430can be used to form an electrical circuit to provide electrical power, grounding or a signal path for the sensor output signals from LRU piezoelectric sensor400. The use of raised terminals420and430eliminates the need for external connectors and wiring by an electrician. Threaded portion416and the complementary threads (not shown) in a socket or female receptacle (not shown) provide the proper index to facilitate a high-integrity electrical connection between terminals420,430and the corresponding electrically conductive members in a socket or female receptacle in a motor housing or casing. LRU piezoelectric sensor400can be internally powered or it can receive electrical power from the motor or device with which it is being used.

Referring toFIG. 2B, there is shown a general block diagram illustrating the operation of piezoelectric (transducer) vibration sensor400shown inFIG. 2A. LRU sensor400is removably positioned in a socket in the casing (not shown) of motor452. LRU sensor400is in electronic signal communication with amplifier (AMP)454. LRU sensor400outputs sensor signals453which are inputted into amplifier454. Amplifier454amplifies and conditions sensor output signals453and may include a transformer to convert power supplied to the motor to a lower voltage and amperage required by the sensors. The amplified and conditioned sensor output signals are then inputted into computer456. Computer456processes the sensor signals with one or more signal processing algorithms that are well known in the art, and then outputs processed signals458that are sent to other equipment and devices in the system network. Computer456also outputs Log Event data460. Computer456also outputs processed signals462for input into variable frequency drive (VFD) device464. In response to processed signals462, VFD464outputs signals466that control the operation (e.g. RPM) of motor452.

Referring toFIG. 2C, there is shown Vibration LRU sensor506in accordance with another embodiment of the present invention. Vibration LRU sensor506is configured to be removably secured or positioned within a socket or female receptacle in a casing of a motor. Such a configuration is shown inFIG. 2Dand is discussed in the ensuing description. LRU sensor506comprises sensor head section508and sensing section509. Vibration LRU sensor506includes top end510and bottom end512similar toFIG. 2A. Sensor head section508has a stepped design configuration that provides different sections, each of which having a cylindrical shape and a different diameter. Top end510has a recess514(shown in phantom) that is which is sized to receive a tool (e.g. hex drive) for installing or removing LRU sensor506from the socket in a machine casing (e.g. motor casing). LRU sensor506as described thus far can be realized by commercially available sensors. In accordance with the invention, LRU sensor506is configured to have electrically conductive members516,518and520that are joined or attached to the exterior surface of sensor head section508. Specifically, each electrically conductive member516,518and520is joined or attached to a corresponding step of the stepped configuration of sensor head section508. In one embodiment, electrically conductive members516,518and520can be configured as raised terminal pins (seeFIG. 1A). In another embodiment, each electrically conductive member516,518and520is configured as a circular, electrically conductive member that has a central opening having a predetermined diameter that allows it to be fitted over the section of sensor head section508that fits within the predetermined diameter. Electrical wires530,532and534extend from sensing section509and are electrically connected to electrically conductive members516,518and520, respectively. Electrical wires530,532and534can provide electrical power and ground, and a signal path for signals outputted sensing section509.

It is to be understood that the particular shapes and configurations of LRU sensor506and electrically conductive members516,518and520pertain to just one embodiment and that LRU sensor506and electrically conductive members516,518and520may have other shapes and configurations. Furthermore, LRU sensor506may be configured to have more or less than three electrically conductive members.

Referring toFIG. 2D, there is shown motor600which has housing602. Housing602includes top cover602A. Motor600further includes shaft603, a rotor and stator assembly. The rotor and stator assembly are not shown but are well known in the art. Motor600includes socket or female receptacle604that is in cover602A. LRU piezoelectric vibration sensor506, previously described in the foregoing description, is removably disposed in socket604. In this embodiment, socket604is configured so as to correspond to the shape and configuration of LRU sensor506. Socket604includes inner wall606which has a stepped configuration that is complementary to the stepped configuration of sensor head section508of LRU sensor506. Socket604includes electrically conductive members620,622and624, each of which being attached or joined to a corresponding step of inner wall606. Electrically conductive members620,622and624of socket604contact electrically conductive members516,518and520, respectively, of LRU sensor506. Motor600includes has cavity630and wireway640that is located in cavity630. Wireway640has a plurality of electrical wires therein. Wireway640includes sections642,644and646. The electrical wires extend through wireway sections642,644and646. Wireway section642has an opening adjacent to electrically conductive member620. The electrical wire in wireway section642is electrically connected to electrically conductive member620. Wireway section644has an opening adjacent to electrically conductive member622. The electrical wire in wireway section644is electrically connected to electrically conductive member622. Similarly, wireway section646has an opening adjacent to electrically conductive member624. The electrical wire in wireway section is electrically connected to electrically conductive member624. The electrical wires carried by wireway640may be connected to electrical power or ground, or may provide a signal path for signals outputted by sensing section509of LRU sensor506. LRU sensor506is completely accessible from outside the motor housing602and thus can be replaced without having to access cavity630of motor600.

In one embodiment, wireway640is located in the gap between the stator coil end turns and motor casing602.

In one embodiment, shown inFIG. 2E, motor600includes connector700attached to housing602. Connector700comprises external electrical interface702and internal electrical interface704. Internal electrical interface704is within motor cavity630. The wires within wireway640are electrically connected to internal electrical interface704. External cable720, only partially shown, connects the external electrical interface702to external junction box740. In the case of a wet cooling tower, junction box740may be positioned on the fan deck. External cable742is connected between junction box740and sensor signal processing equipment that amplifies, conditions and processes the sensor output signals (seeFIG. 2B). External cable744provides electrical power for LRU sensor506. In one embodiment, junction box740includes a signal amplifier that amplifies the signals outputted by LRU sensor506. The amplified sensor output signals are then fed to cable742. In one embodiment, electrical connector700is configured as a quick-disconnect electrical connector which is known in the art. Quick-disconnect electrical connectors are described in international patent application no. PCT/US2016/061244, entitled “Direct Drive Fan System With Variable Process Control” and published on Apr. 25, 2013 under International Publication No. WO 2013/059764. The entire disclosure of international patent application number PCT/US2016/061244 is hereby incorporated by reference.

In an alternate embodiment, cable720is not connected to external junction box740but instead, is electrically connected to a motor control enclosure (MCE) or a motor control center (MCC). Motor control enclosures and motor control centers are described in the aforementioned international patent application number PCT/US2016/061244.

In one embodiment, as shown inFIG. 2F, motor600includes internal junction box750that is located in motor cavity630. Internal junction box750can include electrical power conditioning devices (e.g. transformers) to provide power to the LRU sensor, batteries to power the LRU sensor, battery charging devices, generators, power transmission devices, sensor amplifiers, wireless communication devices and instrumentation termination blocks. For example, internal junction box750may contain amplifier454, computer456and VFD464shown inFIG. 2B. The wires in wireway640are fed into internal junction box750such that the electrical power wires for LRU sensor506are connected to a power conditioning device, battery or power transmission device, and the wires in wireway640that carry the sensor output signals are fed to sensor amplifiers, signal processors or wireless communication devices.

In another embodiment, a generator (not shown) is located in the motor cavity630or on or about the motor. The electrical power generated by the motor shaft and is used to power the LRU sensor and other components at a different voltage than that being supplied to power the motor thus eliminating a transformer.

In a preferred embodiment, each electrically conductive member620,622and624is configured to be a complementary mating connector that mates with electrically conductive members516,518and520, respectively. For example, in one embodiment, each electrically conductive member516,518and520is configured as a raised terminal pin (seeFIG. 1B) and each electrically conductive member620,622and624is configured as a female receptacle (seeFIG. 1B). In another embodiment, each electrically conductive member516,518,520,620,622and624is configured as a raised terminal pin (seeFIG. 1A). In a further embodiment, each electrically conductive member516,518and520is configured as a terminal pin shown inFIG. 1Dand each electrically conductive member620,622and624is configured as the female receptacle shown inFIG. 1D. However, it is to be understood that electrically conductive members516,518and520and electrically conductive members620,622and624, respectively, can be realized by any of the terminal pairs and electrical interfaces shown inFIGS. 1A-1Jas well as any other suitable terminal pairs and electrical interfaces.

It is to be understood that the particular shapes and designs of LRU sensor506and socket604shown inFIG. 2Dpertain to just one embodiment and such configurations and designs may be modified depending upon the particular application or motor design.

Any suitable technique can be used to lock and index LRU sensor506within socket604. For example, in one embodiment, a “push and twist” configuration is used to lock and index LRU sensor506within socket604. In another embodiment, LRU sensor506has threads thereon and inner wall606of socket604has complementary threads thereon to allow LRU sensor506to be screwed into socket604. In a further embodiment, a mechanical capture mechanism such as a bolt or screw fastener is used to lock and index LRU sensor506within socket604.

In a further embodiment, LRU sensor506includes a pair of insert tabs which are similar to the insert tabs described with respect to the embodiment ofFIG. 5, and inner wall606of socket604includes grooves that are similar to grooves2100and2102which are also discussed with respect to the embodiment ofFIG. 5. In this embodiment, LRU sensor506can be installed and indexed in one way only. The user can only rotate the LRU sensor506in one direction to install and index the LRU sensor506in the socket604and then rotate LRU sensor506in the opposite direction to unlock and remove LRU sensor506and prevent misalignment of the assembly.

Referring toFIG. 2D, in one embodiment, motor600includes primary cover660that is removably attached to housing602. Primary cover660includes a seal (not shown) attached to the underside thereof which prevents moisture, water and contaminants from entering motor socket604. The seal attached to primary cover660can be configured as an O-ring type seal. In one embodiment, inner wall606of socket604has a groove formed therein and a secondary seal670is positioned in the groove. Secondary seal670prevents moisture, fluids and other contaminants from entering socket604. Secondary seal670can be configured as an O-ring seal. Secondary seal670can include a wiper gasket to further prevent contaminants from entering socket604.

In an alternate embodiment, LRU sensor506is configured to have a groove in the exterior surface of sensor head section508and an O-ring seal positioned in the groove to prevent moisture, fluids and other contaminants from entering socket604.

In an alternate embodiment, motor600includes a secondary cover and seal that is positioned beneath primary cover660and directly over socket604to protect the entire LRU sensor system from impact, contamination and moisture. This embodiment can be implemented when LRU sensor506is completely recessed in the socket or female receptacle (seeFIG. 1I).

Referring toFIG. 3, there is shown a LRU sensor system in accordance with another embodiment of the present invention. In this embodiment, the LRU sensor system comprises a vertical temperature LRU sensor800. The LRU sensor800may be configured as any suitable temperature sensor device, including but not limited to resistance temperature detectors (RTD), thermocouple sensors and infrared or optical devices for sensing magnet temperatures on a moving rotor. In this embodiment, motor810has casing812, cavity814and socket or female receptacle816in casing812. In accordance with the invention, LRU sensor800can be easily replaced without removing motor810from service and without needing access to the cavity814.FIG. 3shows only a portion of motor810. Motor810includes coil818and laminations819. Coil818has end turns820. Socket816has the same stepped configuration as socket604(seeFIG. 2D) and therefore has a plurality of steps or shoulders to which are joined or attached electrically conductive members that are part of the electrical interface with LRU sensor800. LRU sensor800has generally the same structure as LRU sensor506except that sensing section509is replaced by elongated probe section822that has a predetermined length. In accordance with this embodiment of the invention, thermal well830is embedded into coil818and then LRU sensor800is inserted into socket816such that probe section822is inserted into thermal well830. Thermal well830provides electrical insolation between probe section822and coil818and laminations819. Sensor probe822is calibrated accordingly to compensate for thermal well830. Probe section822has end823to which a stop-end member824is attached or joined. Stop-end member824provides support and prevents movement of probe section822. In another embodiment, stop-end member824includes a spring member so as to provide a degree of tension when LRU sensor800is completely inserted into socket816.

It is to be understood that thermal well830can be formed in other motor components, such as within laminations819, when temperate sensing is required. Wireway850functions in the same manner as wireway640shown inFIG. 2D. Wireway850can located in any one of a variety of suitable locations. For example, wireway850can be located in the gap between the coil end turns820and the interior wall (not shown) of casing812.

The length of probe section822can be varied depending upon the particular motor components, their location within motor cavity814and the portion of the motor component in which temperature information is required.

In an alternate embodiment, probe section822is replaced by a probe that measures temperature at various locations on the length of the probe having a similar structure as probe section1004shown inFIG. 4and discussed in the ensuing description.

In an alternate embodiment, LRU sensor800is configured with an infrared sensor for measuring the temperature of the rotating magnets on the rotor and therefore does not require electrical isolation and thermal well830.

Any of the terminal pairs and electrical interfaces shown inFIGS. 1A-1Jas well as any other suitable terminal pairs and electrical interfaces may be used to realize the electrical interface between LRU sensor800and socket816.

It is to be understood that the particular shapes and designs of LRU sensor506and socket604shown inFIG. 2Dpertain to just one embodiment and such configurations and designs may be modified depending upon the particular application or motor design.

In another embodiment, the electrical power for LRU sensor800and the signal path for the sensor output signals may be realized by the quick-disconnect electrical connector shown inFIG. 2E.

In a further embodiment, the electrical power for LRU sensor800and the signal path for the sensor output signals may be realized by the internal junction box shown inFIG. 2F.

In an alternate embodiment, LRU sensor800is a wireless sensor and motor810includes a receiver or transceiver that receives and transmits the wireless signals from the LRU wireless sensor, conditions these wireless signals and then feeds these conditioned signals into the internal wiring network of the motor. These conditioned signals can then be sent from the motor using the configuration shown inFIG. 2Eto external processing equipment such as a cloud on the internet or a Motor Control Center (MCC).

In an alternate embodiment, LRU sensor800is an optical sensor. In another embodiment, LRU sensor800is a fiber optic sensor. In a further embodiment, LRU sensor800is an infrared sensor.

LRU sensor800includes tool recess840, shown in phantom, which provides the same function as recess514in LRU sensor506. Cover870is removably attached to casing812and has the same structure, purpose and function as cover660shown inFIG. 2D. Cover870may include a seal attached to the underside thereof. Seal880, located in socket816, has the same structure, purpose and function as seal670shown inFIG. 2D.

Any suitable technique can be used to lock and index LRU sensor800within socket816. For example, in one embodiment, a “push and twist” configuration is used to lock and index LRU sensor800within socket816. In another embodiment, LRU sensor800has threads thereon and the inner wall of socket816has complementary threads thereon to allow LRU sensor800to be screwed into socket816. In a further embodiment, a mechanical capture mechanism such as a bolt or screw fastener is used to lock and index LRU sensor800within the socket816.

In a further embodiment, LRU sensor800has insert tabs that are similar to the insert tabs described with respect to the embodiment shown inFIG. 5, and the inner wall of the socket816has the groove formations which are described in the ensuing description related to the embodiment ofFIG. 5. In this embodiment, LRU sensor800can be installed and indexed in one way only. The user can only rotate the LRU sensor800in one direction to install and index the LRU sensor800in socket816, and then rotate LRU sensor800in the opposite direction to unlock and remove LRU sensor800.

Referring toFIG. 4, there is shown an LRU sensor system in accordance with another embodiment of the invention. This drawing figure shows only a portion of motor950with which this LRU sensor system is used. Motor950includes motor cavity952and casing954. Casing954has exterior surface956and a plurality of fins958radially extending from exterior surface956. In this embodiment, the LRU sensor system comprises LRU sensor1000which comprises sensor head section1002, which is substantially the same in construction and configuration as sensor head section508of LRU sensor506(seeFIG. 2D), and probe section1004which is connected to sensor head section1002. Sensor head section1002includes section1003that has recess1030for receiving an installation tool to allow the LRU sensor1000to be installed or removed. Sensor head section1002is positioned within a socket or female receptacle in motor casing954. LRU sensor1000is in a horizontal orientation wherein probe section1004is embedded in the stacked laminations1006of motor950. Probe section1004comprises a plurality of temperature sensing devices1008A-D. Each temperature sensing device1008A-D can be configured as a thermocouple or resistance temperature detector (RTD). Each temperature sensing devices1008A-D senses the temperature at a particular location or point on the stacked laminations1006. Sensing devices1008A-D sense or measure a plurality of temperatures simultaneously at multiple points throughout the stacked laminations1006. Probe section1004includes wires (not shown) that are connected to corresponding temperature sensing devices1008A-D. Similar to LRU sensor506, LRU sensor1000includes electrically conductive members that are attached or joined to the steps or shoulders of sensor head section1002similar to electrically conductive members516,518and520of LRU sensor506(seeFIG. 2C). The wires in probe section1004are electrically connected to the electrically conductive members of sensor head section1002in the same manner that sensor wires532,534and534are electrically connected to electrically conductive members516,518and520, respectively, of LRU sensor506. The socket in motor casing954has the same structure as socket604(seeFIG. 2D) and thus has a stepped configuration that defines steps or shoulders. Each step or shoulder has an electrically conductive member attached or joined thereto which contacts corresponding electrically conductive members that are on sensor head section1002. Probe section1004includes end1010and stop end member1012that is attached to end1010. Stop-end member1012provides support and prevents movement of probe section1004. In another embodiment, stop-end member1012includes a spring member so as to provide a degree of tension when LRU sensor1000is completely inserted into the socket. Wireway1020has the same structure and function as wireway640shown inFIG. 2D. In this embodiment, wireway1020is in communication with main internal wireway1022. Wires (not shown) in main wireway1022can be fed to a quick-disconnect electrical connector as shown inFIG. 2Eor to an internal junction box as shown inFIG. 2F. Any of the electrical interface configurations shown inFIGS. 1A-1J and 2Dmay be used to realize the electrical interface between LRU sensor1000and the socket in motor casing956.

In one embodiment, section1003of sensor head section1002protrudes above exterior surface956of motor casing954. Seal1040has the same configuration and function as seal670shown inFIG. 2Dand creates a seal between sensor section1002and the inner wall of the casing. In another embodiment, an external cover, not shown but substantially the same as660shown inFIG. 2D, is removably attached to exterior surface956of motor casing954to provide further protection for LRU sensor1000and to prevent moisture and contaminants from entering the socket. In one embodiment, sensor section1000and the socket in motor950are configured to implement a “twist and lock” function whereby a user inserts LRU sensor1000into the socket so that probe section1004is inserted between the laminations1006and then the user uses a tool to twist or rotate LRU sensor1000a predetermined angular displacement (e.g. 24°) so as to lock LRU sensor1000in place.

In a further embodiment, LRU sensor1000has insert tabs that are similar to the insert tabs described with respect to the embodiment shown inFIG. 5, and the inner wall of the socket in casing954has the groove formations that are also described in the ensuing description with respect to the embodiment ofFIG. 5. In this embodiment, LRU sensor1000can be installed and indexed in one way only. The user can only rotate the LRU sensor1000in one direction to install and index LRU sensor1000in the socket, and then rotate the LRU sensor1000in the opposite direction to unlock and remove LRU sensor1000.

In an alternate embodiment, a thermal well, similar to thermal well830described in the foregoing description, is used with LRU sensor1000. In such an embodiment, the thermal well is inserted into laminations1006and probe section1004is inserted into the thermal well. The thermal well electrically isolates probed section1004from laminations1006.

In an alternate embodiment, LRU sensor1000is an optical sensor. In another embodiment, LRU sensor1000is a fiber optic sensor. In a further embodiment, LRU sensor1000is an infrared sensor and is comprised of a material that electrically isolates the probe from the motor and eliminates the need for a thermal well.

Referring toFIG. 5, there is shown a diagram which shows a plan view of an LRU sensor socket2000and corresponding printed circuit in accordance with another embodiment of the present invention. This view looks into LRU sensor socket2000. Socket2000has an inner wall2016which is described in detail in the ensuing description. Socket2000has central opening2017through which a portion of an LRU sensor extends. Socket2000is sized to receive an LRU sensor (not shown). The LRU sensor that can be used with socket2000can be a sensor to sense vibrations, gas, temperature or airflow. The printed circuit comprises three discrete electrically conductive circuits2020,2022and2024that coincide and directly interface with the terminals on a LRU sensor that is installed in socket2000and properly indexed. Circuits2020,2022and2024provide power, communication and grounding for the LRU sensor. Circuits2020,2022and2024have extending portions2030,2040and2050, respectively, that extend away from socket2000for a predetermined distance. Each extending portion2030,2040and2050may be terminated at a corresponding terminal (not shown) which may be in the motor cavity or in the top cover of the motor housing. In such an embodiment, individual wires of a multi-strand cable can be attached to the terminals. In a preferred embodiment, the printed circuit is formed on an electrically insulating substrate such as silicone. In one embodiment, circuits2020,2022and2024are formed on a printed circuit board. Circuits2020,2022and2024can be directly electrically connected to the internal motor wireway. Circuits2020,2022and2024can be located in motor housing, such as the top cover of the motor housing.

Socket2000is configured to work with an LRU sensor that has electrical conductors formed on the bottom of the sensor head. These electrical conductors are arranged so that they are the mirror image of circuits2020,2022and2024such that when the LRU sensor is completely installed and properly indexed in socket2000, the electrical conductors on the bottom of the sensor head contact circuits2020,2022and2024.

Referring toFIG. 5, socket2000and its corresponding LRU sensor are configured to implement a “turn and lock” or “rotate and lock” function. The LRU sensor (not shown) includes diametrically positioned insert tabs that are sized to fit into corresponding downwardly extending grooves or slots2100and2102formed in inner wall2016of socket2000. Inner wall2016also has a pair of relatively shorter grooves that extend along the circumference of the socket inner wall either in a clockwise direction or counter-clockwise direction. In a preferred embodiment, both shorter grooves extend in a clockwise direction. Each shorter groove starts at the bottom of a corresponding downwardly extending groove. In one embodiment, the length of each of the shorter grooves translates to an angle θ of 24° along the circumference of the socket inner wall. In order to install the LRU sensor, the user aligns each insert tab on the LRU sensor with a corresponding one of grooves2100and2102. Once each insert tab enters the corresponding groove2100or2102, the user then moves the LRU sensor downward until the insert tabs reach the end of grooves2100and2102. The user then rotates LRU sensor2000clockwise such that the each insert tab enters a corresponding shorter groove. The insert tabs continue to move along the shorter grooves until the insert tabs reach the end of the shorter grooves. Once this occurs, the LRU sensor is locked in place and properly indexed. In one embodiment, the length of the shorter grooves translates to about 24° in the clockwise direction. In order to remove the LRU sensor from socket2000, the user rotates the LRU sensor in the counter-clockwise direction (e.g. 24°) and then lifts the LRU sensor upward so that insert tabs move upward through grooves2100and2102. Similar to the other embodiments described in the foregoing description, the LRU sensor is configured with a recess sized to receive a tool which allows a user to rotate the LRU sensor when it is positioned in socket2000.

Referring toFIG. 6, there is shown LRU sensor system that uses a printed circuit interface in the same manner as shown inFIG. 5. Apparatus3000can be a motor, compressor, turbine, pump or similar machines. Apparatus3000comprises casing3002. Casing3002comprises exterior surface3004and cover3005. Apparatus3000includes cavity or interior3006. In this particular embodiment, apparatus3000is a motor that includes stator3008. Stator3008comprises coils3010and stator core3012. Coils3010are wrapped about stator core3012and have coil end turns3014. Casing3002includes a socket that is configured for receiving LRU temperature sensor3100. Sensor3100includes sensor head section3102and sensor probe section3104that is joined or attached to sensor head section3102. Sensor head section3102has exterior surface3103. Sensor section head3102is positioned in the socket in casing3002. LRU sensor3100is used with thermal well3120. The thermal well3120extends through the coil end turns3014and into stator core3012. The thermal well3120has the same structure as thermal well830shown inFIG. 3. Thermal well3120electrically isolates sensor probe section3104from stator coils3010and stator core3012. Sensor probe3104is disposed within thermal well3120and measures or senses the temperature in stator core3012. LRU sensor3100includes electrical conductors3200and3202that are joined or attached to the bottom of sensor head section3102. Electrical wires (not shown) electrically connect the sensor probe3104to electrical conductors3200and3202. The LRU sensor system includes electrical circuit board3300which is attached to interior motor structure3400. Electrical circuit board3300is electrically isolated from interior motor structure3400. Insulators3310allow electrical circuit board3300to be attached to interior motor structure3400while keeping electrical circuit board3300electrically isolated from the interior motor structure3400. Electrical circuit board3300comprises corresponding electrical conductors that contact the electrical conductors3200and3202attached to the bottom of LRU sensor head section3102when the LRU sensor3100is properly installed and indexed in the socket. Wires and cables (not shown) are electrically connected to electrical circuit board3300and extend through wireway3500. The wires in wireway3500may be electrically connected to an electrical connector similar to electrical connector700shown inFIG. 2Eor to an internal junction box similar to junction box750shown inFIG. 2F. In one embodiment, electrical conductors3200and3202are configured as printed circuit terminals and the corresponding electrical conductors of electrical circuit board3300are configured as complementary mating printed circuit terminals. Any of the techniques and configuration described in the foregoing description may be used to insert and lock LRU sensor3100in the socket. LRU sensor3100may be installed or removed without having to remove the motor and without needing access to the interior of the motor

In alternate embodiments, any of the electrical interface configurations shown inFIGS. 1A-1J and 2Dmay be used to realize the electrical interface between electrical conductors3200and3202and the electrical conductors on printed circuit board3300.

Sensor probe section3104includes stop end member3600which has the same structure and function as stop end member824shown inFIG. 3.

As shown inFIG. 6, cover3005covers LRU sensor3100and the socket so as to prevent moisture and contaminants from entering the socket. Cover3005has an underside and may include a seal or gasket attached or joined to the underside.

As shown inFIG. 6, seal3650is joined or attached to either the inner wall of the socket or to exterior surface3103of sensor head section3102. Seal3650performs the same function as seal670shown inFIG. 2D.

Referring toFIG. 7, there is shown another LRU sensor system that uses a printed circuit interface in the same manner as shown inFIG. 5. Apparatus4000can be a motor, compressor, turbine, pump or similar machines. In this embodiment, apparatus4000is a motor. Motor4000comprises casing4002. Casing4002comprises motor cover4003and mounting boss4004. Mounting boss4004has a socket or female receptacle, the purpose of which is discussed in the ensuing description. Motor4000includes cavity or interior4006and stator assembly4008. Stator assembly4008comprises coils4010and stator core4012. Coils4010are wrapped about stator core4012and have coil end turns4014. Motor4000includes top mounted LRU gas sensor4100. LRU gas sensor4100is a single piece unit and comprises connector head section4102and gas sensor section4104. LRU gas sensor4100has a shape that is similar to the shape of a ratchet wrench. The female receptacle or socket in mounting boss4004and connector head section4102are configured to have structures that allow connection head section4102to be inserted into the socket in mounting boss4004and then rotated for a predetermined angular displacement (e.g. 24°) until connector head4102is locked in the socket. These aforementioned structures of the socket in mounting boss4004and connector head section4102are similar to the same configuration used to lock an LRU sensor in socket2000as shown inFIG. 5. Thus, in order to mount LRU gas sensor4100to motor4000, a user maneuvers LRU gas sensor4100so that connector head4102is inserted into the socket in mounting boss4004and then rotates LRU gas sensor4100in a clockwise direction (e.g. 24°) until connector head4102is locked in place. When LRU gas sensor4100is indexed and completely mounted to motor4000, gas sensor section4104is positioned in the airflow or airstream at a predetermined radius from the center of the cooling tower fan in order to sense gases such as hydrogen which present an explosive hazard.

Seal4200is attached or joined to the portion of gas sensor section4104that confronts mounting boss4004so that when LRU gas sensor4100is mounted to motor4000, seal4200creates a seal that prevents moisture and contamination from entering the socket in mounting boss4004. In one embodiment, seal4200is configured as an O-ring.

Electrically conductors4202and4204are joined or attached to the bottom of connector head section4102. Electrical wires (not shown) internal to connector head section4102electrically connect gas sensor section4104to electrical conductors4202and4204. In one embodiment, electrical conductors4202and4204may provide electrical power to LRU gas sensor4100or create a signal path for sensor output signals. If gas fumes enter gas sensor section4104, the circuitry in gas sensor section4104detects the presence of gas and generates electrical signals that represents the measured amount of gas fumes. These electrical signals are fed to electrical conductors4202and4204. The LRU sensor system includes electrical circuit board4300that is attached to but electrically isolated from interior motor structure4400. Insulator members4310are used to attach electrical circuit board4300to interior motor structure4400but also electrically isolate electrical circuit board4300from interior motor structure4400. Electrical circuit board4300includes corresponding electrical conductors that contact electrical conductors4202and4204. Wires and cables (not shown) are electrically connected to electrical circuit board4300and extend through wireway4500. The wires in wireway4500may be electrically connected to an electrical connector similar to electrical connector700shown inFIG. 2Eor to an internal junction box similar to junction box750shown inFIG. 2F. In one embodiment, electrical conductors4202and4204are configured as printed circuit terminals and the corresponding electrical conductors of electrical circuit board4300are configured as printed circuits that will electrically interface with electrical conductors4202and4204.

In an alternate embodiment, LRU gas sensor4100is screwed onto motor casing4002similar to mounting or screwing an oil filter onto an automobile engine. In such an embodiment, the screw and mounting arrangement determines the proper index for circuit continuity and airflow orientation. In other embodiments, other mounting arrangements include seals, index pins, screws, bolts and push/twist/lock configuration. In other embodiments, the LRU gas sensor is mounted on other locations on motor casing4002.

In another embodiment, the LRU gas sensor is a wireless sensor which emits wireless signals that are received and coupled into the wiring network of the cooling tower and/or motor. In such an embodiment, the LRU gas sensor is mounted to the motor as described in the foregoing description and a receiver device is positioned within the motor cavity. The wireless signals from the LRU gas sensor are converted into digital signals which are then fed to other devices such as signal conditioners, digital acquisition devices, industrial computers and display devices such as monitors.

Other Embodiments of the LRU Sensor System of the Present Invention

It is to be understood that the terminal pairs and electrical interfaces shown inFIGS. 1A-1Jare just examples and that any other suitable terminal pairs and electrical interfaces may be used to realize the electrical interface between LRU sensors and the internal wiring of a motor or other machine. Furthermore, it is to be understood that the shapes and sizes of the terminal pairs and electrical interfaces shown inFIGS. 1A-1Jare just examples and that the terminal pairs and electrical interfaces may have other shapes and sizes.

In alternate embodiments, any of the foregoing LRU sensors may be hardwired to to either a wireway that is internal to the motor or a wireway that is external to the motor. An electrician may perform this task.

In an alternate embodiment, the LRU gas sensor is a wireless gas sensor but is not mounted on the motor but instead, is positioned at another location in the cooling tower and in contact with the airstream. The LRU gas sensor may be battery powered or receive electrical power via a hardwire connection with the cooling tower wiring network or powered wirelessly. In such an embodiment, a wireless receiver is positioned in an external junction box on the fan deck or in a MCE (motor center enclosure) or MCC (motor control center). The wireless receiver device is hardwired to the wiring in the aforementioned junction box, MCE or MCC and converts the received wireless signals from the wireless LRU gas sensor into digital signals which are then fed into the wiring network of the cooling tower and motor. These digital signals are also inputted into signal processing equipment such as signal conditioners, analyzers, data acquisition devices, computers and display screens.

In another embodiment, LRU gas sensors are mounted at other locations in the cooling tower but are hardwired into the cooling tower wiring network so that the LRU gas sensors are in electrical signal communication with the motor and external signal conditioning and analysis equipment.

In an alternate embodiment, an integrated printed circuit and wireway can be formed on either side of the motor housing for the LRU sensor.

In another embodiment, the external surface of a motor or other machine is configured to have integrated printed circuits (seeFIG. 5) and wireways wherein the integrated printed circuits are in electrical signal communication with the LRU sensors, the internal wiring network of the motor or machine, or other components of the motor or machine.

In another embodiment, the motor or machine includes a cover that covers the LRU sensor when the LRU sensor is in the socket in the casing of the motor or machine, wherein the cover includes a printed circuit. The printed circuit can be integral with the cover or a separate assembly that is joined or attached to the cover. The printed circuit is electrically connected to the terminal block. This configuration is applicable to LRU sensor2000shown inFIG. 5.

In other embodiments, the motor casing and cover are configured to have internal wiring and wireways. In one embodiment, the cover is a multi-piece cover and comprises a separate printed circuit that is joined or attached to the cover but remains electrically isolated from the cover. In this embodiment, the printed circuit becomes the terminal block wherein all terminal points are electrically connected to an electrical interface connector on the motor or machine.

In another embodiment, the LRU sensor system of the present invention comprises a LRU sensor that is configured as a rotating-component temperature sensor. In such an embodiment, the LRU sensor is an infrared temperature sensor (e.g. infrared laser or other optical sensor) or other heat-sensor device that is directed toward permanent magnets that are attached to and rotate with the motor rotor. In this embodiment, the LRU sensor measures or senses the temperature of the permanent magnets during rotation of the rotor. Thus, in this embodiment, the LRU sensor measures the temperature of moving components. In another embodiment, the LRU sensor is used in an inside-out motor wherein the stator rotates. In such an embodiment, the LRU sensor measures the temperature of the rotating stator.

In another embodiment, the LRU sensor of the LRU sensor system of the present invention is a wireless airflow sensor that is mounted at different locations in the cooling tower. A receiving device is positioned in the external junction box, MCC or MCE and receives the wireless signals and converts these wireless signals into digital signals which are then fed into the cooling tower wiring network so that so that such signals can be processed and monitored by external signal conditioning devices, computers, digital acquisition devices, and display screens. In one embodiment, the wireless airflow sensor is configured as a wireless pressure sensor.

In another embodiment, the LRU sensor of the LRU sensor system of the present invention is a wireless temperature sensor that is external to the motor and mounted at a particular location in the cooling tower to measure the temperature of the cooling tower air or water such as in the collection basin. A receiving device is positioned in the external junction box, MCC or MCE and receives the wireless signals and converts these wireless signals into digital signals which are then fed into the cooling tower wiring network so that so that such signals can be processed and monitored by external signal conditioning devices, computers, digital acquisition devices, and display screens.

In other embodiments, the foregoing LRU sensors may be configured as optical sensors, RF sensors, optical encoders or photonic sensors. In such embodiments, the appropriate circuits and wiring networks are used with such sensors. Photonic sensors can be realized by photonic integrated circuits.

In other embodiments, the foregoing LRU sensors are integrated wireless sensors and configured for “plug and play” operation and comprise built-in amplifiers, transformers and cell phone wireless or optical wireless communication transmitters and receivers that can be used for system feedback and sensor calibration while installed and operating.

In other embodiments, the foregoing LRU sensors are configured for “plug and play” operation and connected internally to electrical and communication systems within the motor cavity. In this embodiment, the LRU sensor signals are transmitted via a wireless network in, on or about the motor.