Electromechanical Relay Structure

Abstract

To accurately provide information associated with a temperature in a relay on which a temperature rise of a contact is reflected at proper time or in response to such a temperature rise.SOLUTION: Electromechanical relay constructions comprise an external housing (102), a pair of switchable electrical contacts (104, 106) disposed within the housing, an element for activating the pair of electrical contacts, and a temperature sensing element (118) disposed within the housing adjacent to the electrical contacts. The temperature sensing element provides a signal for determining the temperature within the relay housing. The temperature sensing element may be attached to a member or substrate (115) disposed within the housing, may be attached to an existing internal structure of the housing, or may be attached to one of the contacts. The temperature sensing element (118) may be selected from the group consisting of resistance temperature detectors, negative temperature coefficient thermistors, thermopile sensors, thermocouples, and combinations thereof.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The electromechanical relays disclosed herein are constructed to provide information regarding the desired operating conditions of the relay, and such information can be used to monitor the performance of the relay and determine whether the relay is performing within or outside of predetermined operating parameters. [Background technology]

[0002] The use of relays, such as electromechanical relay devices, to provide electrical switching functions is well known in the art. Such relay devices are generally electrically operated switches used to control the presence or absence of electrical current flowing in a circuit between electrical components, such as from a power source to one or more electrical components receiving power from a power source. Some relays use an electromagnet to mechanically operate the switch. The electromagnet is configured to physically move a movable electrical contact relative to one or more stationary relay contacts. The movable electrical contact can make or close a circuit (allowing current to flow through the circuit) when the movable relay contact engages one or more of the stationary relay contacts. Moving the movable electrical contact away from the stationary relay contacts breaks or opens the circuit (stopping the flow of current through the circuit) and / or closes another circuit.

[0003] Such relays can be used for a variety of different switching functions, including power applications involving high levels of current. The surfaces of such contacts are often failure points in high current applications. Potential indications of impending failure of the relay include, for example, an increase in the temperature of the contacts caused by resistive heating as the contacts deteriorate with use. Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved is the desire to construct a relay to provide information regarding the temperature condition of the relay, where such information can be provided locally, for example at the relay itself, or can be transmitted to a remote location for remote relay monitoring if desired. It would be further desirable for such a relay to be constructed to accurately provide information regarding the temperature within the relay, reflecting a temperature increase at the contacts, in a timely manner, or in response to any such temperature increase. It would be further desirable for such a relay to include this functionality in a manner that does not increase the overall size of the relay to the extent possible. [Means for solving the problem]

[0005] A solution is provided by an electromechanical relay structure disclosed herein, which generally includes an outer housing, a pair of switchable electrical contacts disposed within the housing, an element for activating the pair of electrical contacts, and a temperature sensing element disposed within the housing adjacent to the electrical contacts. The temperature sensing element or sensor can be connected to one or more electrical contacts extending to a location outside the housing to receive an output signal, or can be configured with an element for providing the output signal wirelessly from the relay. The relay can include two or more temperature sensing elements disposed within the housing at a desired distance from each other. In one example, the temperature sensing element can be attached to a member mounted within the housing and positioned adjacent to the electrical contacts on the member. In one example, the temperature sensing element is connected to a portion of one of the contacts. In one example, the temperature sensing element is disposed along an existing internal structure of the relay, the internal structure being adjacent to one or both of the stationary and moving contacts. The temperature sensing element may be selected from the group consisting of a resistance temperature detector, a negative temperature coefficient thermistor, a thermopile sensor, a thermocouple, and combinations thereof. The relay structure may include two or more pairs of switchable electrical contacts disposed within the housing.

[0006] The temperature within such an example electromechanical relay structure can be determined by operating the electromechanical relay to bring the contacts into contact with each other and monitoring the output from a temperature sensing element disposed within the relay housing to determine the temperature within the relay when the contacts are in contact with each other in a steady state condition and / or when the contacts are switched on and off.

[0007] The invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0008] The electromechanical relay or relay structure disclosed herein will now be described, by way of example, with reference to the accompanying drawings, in which: FIG. [Brief description of the drawings]

[0009] [Figure 1A] FIG. 2 is a side perspective view of an exemplary relay structure disclosed herein. [Figure 1B] FIG. 1B is a top view of the example relay structure of FIG. 1A. [Figure 1C] FIG. 1B is a front view of the exemplary relay structure of FIG. [Figure 1D] FIG. 1B is a side view of the example relay structure of FIG. [Figure 1E] FIG. 1B is a cutaway bottom view of the example relay structure of FIG. 1A. [Diagram 2] FIG. 2 is a cutaway front view of an exemplary relay structure disclosed herein. [Diagram 3] FIG. 2 is a cutaway front view of another exemplary relay structure disclosed herein. [Figure 4] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Diagram 5] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Figure 6] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Figure 7] FIG. 2 is a cutaway front view of another exemplary relay structure disclosed herein. [Figure 8] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Figure 9] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Figure 10] FIG. 2 is a cutaway front view of another exemplary relay structure disclosed herein. [Figure 11] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Figure 12] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. [Figure 13] FIG. 2 is a cutaway top view of another exemplary relay structure disclosed herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A relay structure disclosed herein generally comprises a housing and a pair of contacts disposed within the housing, the relay configured to include a temperature sensor disposed within the relay that is constructed and / or positioned to be purposefully designed to accurately provide an indication of the contact temperature in response to an increase in temperature for purposes of monitoring the operating condition of the contacts within the relay. In one example, such temperature information can be used for safety purposes, where failure of the relay may pose a safety hazard, and / or for preventative maintenance purposes, such as to remove the relay from service after a predetermined temperature condition is detected and before failure occurs. In one example, such temperature information may be useful in detecting or indicating a fault in a system or component connected to the relay, e.g., a short circuit in one or more connected components and / or circuits. Such a fault would be indicated by a sudden increase in contact current and therefore contact temperature. In an exemplary embodiment, the relay may be configured to transmit such temperature information to a remote location for such monitoring purposes. In an exemplary embodiment, such a relay structure may be used in power applications involving high current levels, although it should be understood that the relay structures disclosed herein may also be used in a variety of other relay applications in which such temperature information may be useful.

[0011] 1A-1E show different views of an example relay 10 that can be configured with the temperature sensor mechanism disclosed herein. FIGURES 1A-1D show the example relay 10 with a housing 12 having a top 14, a front 16, sides 18 and 20, a rear 22, and a bottom 24. The housing can include a latch 25 configured to releasably connect the housing 12 to the bottom 24. The rear 22 of the housing can include an electrical switching terminal 26 and a power terminal 28 projecting outwardly therefrom for connection with electrical connections required to provide the desired electrical switching of power transmission through the relay.

[0012] FIGURE 1E illustrates an internal view of an exemplary relay 10 with a pair of contacts 30 including a non-movable or stationary contact 32 and a movable contact 34. Each contact 30 and 32 has a respective contact pad 35 and 36 disposed thereon, the contact pads 35 and 36 positioned on the contacts such that they contact one another when the movable contact is moved toward the stationary contact. In FIGURE 1E, the pair of contacts is shown in an open position, with the pad 36 of the movable contact 34 not touching or making contact with the pad 35 of the stationary contact 32. As shown, the contacts 32 and 34 are each connected to a respective electrical terminal 28 extending from the relay.

[0013] As mentioned above, a feature of the relay structures disclosed herein is the inclusion of a temperature sensor disposed within the housing in close proximity to one or both of the contacts. Temperature sensors useful in such structures can be of a variety of different types for detecting the temperature within the relay indicative of the contact temperature and can provide an output signal therefrom using a processor, controller, or other device configured to receive an input signal and determine the temperature therefrom for purposes of determining the temperature. In exemplary embodiments, temperature sensors useful in forming the relay structures disclosed herein can be in the form of contact and / or infrared temperature sensors selected from the group including, but not limited to, resistance thermometers or resistance temperature detectors (RTDs), NTC thermistors or temperature sensors, transducers, silicon-based temperature sensors, thermopiles or infrared temperature sensors, and the like.

[0014] The type of temperature sensor used may affect where the temperature sensor is implemented to obtain a sensitive and accurate indication of the temperature and / or temperature changes of the contacts within the relay. The following description and figures introduce, for purposes of reference and illustration, different example relay construction embodiments including different temperature placement locations that may be affected by the type of temperature sensor.

[0015] 2 illustrates a cross-sectional cutaway front view of an exemplary relay structure 100 disclosed herein, including a housing 102, a pair of contacts 104 and 106, electrical terminals 108 and 110 connected to the respective contacts 104 and 106, and the remaining elements included within the relay structure illustrated in FIG. 1E. In this example, a temperature sensor 112 is positioned adjacent to a bottom surface 113 of the housing, or the temperature sensor 112 can be mounted to or otherwise attached to the bottom surface of the housing. In one example, the contacts 104 and 106 each include a respective contact pad 114 and 116 attached to the contacts 104 and 106, the contact pads 114 and 116 positioned to contact one another when the contacts are in a closed state.

[0016] In one example, the temperature sensor 112 can include a printed circuit board 115 having a sensor element 118 mounted thereon. In one example, the printed circuit board can be configured with an integrated circuit for powering and / or receiving an output signal from the sensor element, and can also include an electrical connector (not shown) extending therefrom to the outside of the housing for electrically connecting to and receiving an output signal from the sensor element. Alternatively, the temperature sensor can be connected to components useful for wirelessly receiving and / or providing an output signal. In one example, the sensor element 118 can be an RTD / NTC type temperature sensor or a thermopile / IR sensor that monitors a contact surface or one or both contacts for faster response readings. In this example, the temperature sensor 112 is positioned adjacent to the pair of contacts 104 and 106, and more specifically, along a plane that is parallel to and lies above a longitudinal axis extending along the length of the contacts.

[0017] In an exemplary embodiment, the temperature sensor is positioned at a distance directly above the pads of the contacts. In an exemplary embodiment, the temperature sensor element is positioned at a distance of about 1 mm to 10 mm, about 2 mm to 5 mm, and about 2 mm to 4.2 mm from the contact pads 114 and 116 of the respective contacts 104 and 106. While placement distances for the temperature sensor in this example are provided, it should be understood that such distances can and do vary depending on factors such as the type of relay and the particular type of sensor device used.

[0018] 3 shows a cutaway front view of an exemplary relay structure 140 disclosed herein, comprising a housing 102, a pair of contacts 104 and 106, electrical terminals 108 and 110 connected to the respective contacts 104 and 106, and the remaining elements included in the relay structure shown in FIG. 1E. In this example, the relay structure 140 comprises the same temperature sensor 112 as described above with respect to the example shown in FIG. 2, comprising a printed circuit board 115, a sensor element 118 mounted on the printed circuit board 115, and electrical terminals (not shown) extending therefrom. Alternatively, as described above, the temperature sensor can be configured to receive and / or provide signals wirelessly. In this example, the temperature sensor element is positioned at a different location within the housing, specifically adjacent to one of the contacts. In this particular example, the temperature sensor element is positioned a distance above the movable contact, contact 106. In this example, the temperature sensor element is positioned along a plane perpendicular to a longitudinal axis extending along the length of the contact. In one example, the temperature sensor element is positioned a distance relative to the movable sensor, the distance varying depending on the particular relay and the travel distance of the movable contact 106. In one example, the temperature sensor is positioned approximately 0.5 mm or more from the contact pad 116 of the movable contact 106. In one example, the temperature sensor may be positioned approximately 0.5-5 mm from the contact pad 116 of the movable contact.

[0019] 4 illustrates a cutaway top view of an exemplary relay structure 150 disclosed herein, which includes a housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure illustrated in FIG. 1E. In this example, the relay structure 150 includes the same temperature sensor 112 described above with respect to the example illustrated in FIG. 2, which may include a printed circuit board 115, a sensor element 118 mounted on the printed circuit board 115, and electrical terminals (not shown) extending therefrom, or may be configured to receive and / or provide information wirelessly. In this example, the temperature sensor element is positioned at a different location within the housing, specifically positioned adjacent to and in front of the pair of contacts. In this particular example, the temperature sensor element is positioned in front of and at a distance from the pads 114 and 116 of both contacts 104 and 106. In this example, the temperature sensor element is positioned along a plane perpendicular to and intersecting a longitudinal axis extending along the length of the contacts. In one example, the temperature sensor element is positioned about 0.5 mm to about 8 mm from the pads 114 and 116 of the respective contacts 104 and 106.

[0020] 5 illustrates a cutaway top view of an exemplary relay structure 160 disclosed herein, comprising a housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure illustrated in FIG. 1E. In this example, a temperature sensor 162 is positioned within the housing adjacent to an internal housing structure, which may be pre-existing or may be formed, e.g., molded, for the purpose of mounting the temperature sensor. In this example, the temperature sensor 162 is bonded or otherwise attached to an internal housing wall 164 extending inwardly from the side 20 of the housing and positioned a distance in front of the pads 114 and 116 of the contacts 104 and 106. A feature of the temperature sensor 162 in this particular example is that the temperature sensor 162 is in the form of a sensor element selected from the types discussed above and is bonded or otherwise attached to the relay structure without the use of a substrate PC board or the like. The temperature sensor 162 may be in electrical contact with electrical terminals (not shown) extending from the housing 102 for electrically connecting to the temperature sensor and receiving an output signal therefrom, or alternatively may be configured to receive and / or provide signals wirelessly from the relay. In one example, the sensor element may be a transducer. In this example, the temperature sensor 162 is positioned in front of the pair of contacts 104 and 106, more specifically, at a distance along a plane perpendicular to and intersecting a longitudinal axis extending along the length of the contacts.

[0021] In an exemplary embodiment, the temperature sensor 162 is positioned at a distance just in front of the contacts. In an exemplary embodiment, the temperature sensor is positioned at a distance of about 0.5 mm to 5 mm, and about 0.1 mm to 1.5 mm from the contact pads 114 and 116 of the respective contacts 104 and 106. In an exemplary embodiment, the temperature sensor element is positioned at a distance of about 0.3 mm from the pads of the contacts. It should be understood that although placement distances for the temperature sensor are provided, such distances can and do vary depending on factors such as the type of relay and the particular type of sensor element used.

[0022] 6 illustrates a cutaway top view of an exemplary relay structure 170 disclosed herein, comprising a housing 102, a pair of contacts 104 and 106, electrical terminals 108 and 110 connected to the respective contacts 104 and 106, and the remaining elements included within the relay structure illustrated in FIG. 1E. As with the above example illustrated in FIG. 5, in this example, a temperature sensor 162 is configured in the same manner as described with respect to the exemplary relay structure of FIG. 5, and may be electrically connected to electrical terminals extending from the housing (not shown) or may alternatively be configured to receive and / or provide signals wirelessly from the relay. The temperature sensor is positioned within the housing adjacent to an internal housing structure, which may be pre-existing or may be formed, e.g., molded, for purposes of mounting the temperature sensor. In this particular example, the temperature sensor 162 is bonded or otherwise attached to an interior housing wall 172 that extends along the inside surface of the housing side 20 and is positioned a distance behind one of the contacts. In this example, the temperature sensor 162 is positioned behind the stationary contact 104. In one example, the temperature sensor 162 may be positioned within the same distance parameters discussed above with respect to the exemplary relay structure shown in FIG. 5 as measured from the rear face of the contact 104 to the sensor 162.

[0023] 7 illustrates a cutaway front view of an exemplary relay structure 180 disclosed herein, including a housing 102, a pair of contacts 104 and 106, electrical terminals 108 and 110 connected to the respective contacts 104 and 106, and the remaining elements included in the relay structure illustrated in FIG. 1E. Similar to the above example illustrated in FIG. 5, in this example, a temperature sensor 162 is electrically connected to electrical terminals extending from the housing (not shown) and may be configured to receive and / or provide signals wirelessly. The temperature sensor 162 is positioned within the housing adjacent to an internal housing structure, which may be pre-existing or may be formed, e.g., molded, for purposes of mounting the temperature sensor. In this particular example, the temperature sensor 162 is bonded or otherwise attached to the inner surface 182 of the housing top 14 and is positioned a distance beneath the pads 114 and 116 of the contacts 104 and 106. In one example, the temperature sensor 162 may be positioned approximately 1-10 mm, and approximately 2-5 mm, measured from the pads to the sensor.

[0024] 8 illustrates a cutaway top view of an exemplary relay structure 190 disclosed herein, comprising a housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure illustrated in FIG. 1E. In this example, a temperature sensor 192 is positioned within the housing, and may be formed, bonded, or otherwise attached to the structure of one of the contacts 104 and 106, such as by a plasma vapor deposition process. While the temperature sensor in this example is attached directly to the contacts, it should be understood that the temperature sensor used in such examples may be formed as a transducer, i.e., formed into the contact itself, or may be an existing package or transducer that is attached to the contacts (after formation). In this example, the temperature sensor 192 is in the form of a sensor element selected from the types described above and is in electrical contact with electrical terminals (not shown) extending from the housing 102 for electrically connecting to and receiving an output signal from the temperature sensor, or configured to provide or receive a signal wirelessly from a relay structure. In one example, the sensor element can be a transducer (formed in or existing in and attached to the contact). In this example, the temperature sensor 182 is attached to the rear surface 184 of the stationary contact 104 opposite the pad 114. In one example, the contact pad 114 can be configured such that a portion 186 of the pad passes through the contact 104 and the temperature sensor is attached to the rear of the contact pad itself. Mounting the temperature sensor in such a manner facilitates increased response to changes in contact temperature. In one example, for some applications, it may be desirable for the sensing element to be electrically isolated from the contact surface. Such electrical isolation can be achieved by a variety of methods, including, but not limited to, deposition of an insulating layer, a coating or film on the contact, or packaging the sensing element in a dielectric enclosure or case formed from an electrically insulating material such as a polymer. In one example, such an approach should operate to maximize electrical isolation while minimizing thermal isolation.

[0025] FIG. 9 illustrates a cutaway top view of an exemplary relay structure 200 disclosed herein, comprising a housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure illustrated in FIG. 1E. Similar to the above example illustrated in FIG. 8, in this example, a temperature sensor 182 is disposed within the housing and electrically connected to an electrical terminal extending from the housing (not shown), or the temperature sensor 182 can be configured to receive or provide a signal wirelessly from the relay structure. In this example, the temperature sensor 182 is attached to the rear surface 202 of the movable contact 106 opposite the pad 116. In one example, the contact pad 116 can be configured such that a portion 204 of the pad penetrates the contact 106, and the temperature sensor is attached to the rear of the contact pad itself. Attaching the temperature sensor in this manner facilitates increased response to changes in contact temperature.

[0026] FIG. 10 shows a cutaway front view of an exemplary relay structure 210 disclosed herein, including a housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure shown in FIG. 1E. Similar to the above example shown in FIG. 8, in this example, a temperature sensor 182 is disposed within the housing and electrically connected to an electrical terminal extending from the housing (not shown), or the temperature sensor 182 can be configured to receive or provide a signal wirelessly from the relay structure. In this example, the temperature sensor 182 is mounted on a portion 212 of the stationary contact 104 at a distance from the contact pad 114 toward the electrical terminal 108. Alternatively, the temperature sensor can be mounted on a portion of the movable contact 106 at a distance from the contact pad 116. In one example, the temperature sensor 182 is positioned at a distance of about 0.2 mm to 25 mm, about 0.5 mm to 19 mm, and about 0.8 mm to 10 mm from the contact pad 114 of the contact 104. In an exemplary embodiment, the temperature sensor is positioned at a distance of about 1.3 mm from the contact pad. It should be understood that although placement distances for the temperature sensor are provided, such distances can and do vary depending on factors such as the type of relay as well as the particular type of sensor element used.

[0027] While the relay structures disclosed herein shown in Figures 2-10 provide examples of different embodiments involving the use of different types of temperature sensors and placement locations of the temperature sensors within the relay, it may be desirable to include more than one temperature sensor within the relay for purposes of providing differential / gradient temperature measurements. Such differential / gradient temperature measurements that can be obtained from the use of multiple temperature sensors are desirable for providing near instantaneous calculation of contact temperatures. Accordingly, the following exemplary relay structures are provided for purposes of reference of such embodiments with multiple temperature sensors disposed within the relay structure.

[0028] 11 illustrates a cutaway top view of an exemplary relay structure 220 somewhat similar to the example illustrated in FIG. 8, the relay structure 220 comprising the housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure illustrated in FIG. 1E. In this example, the relay structure comprises two temperature sensors 222 and 224 positioned within the housing, which may be formed, bonded, or otherwise attached to the structure of one of the contacts 104 and 106, such as by a plasma vapor deposition process. In this example, the temperature sensors 222 and 224 are in the form of sensor elements selected from the types discussed above, and are in electrical contact with one or more electrical terminals (not shown) extending from the housing 102 for purposes of electrically connecting to and receiving an output signal from the temperature sensors. Alternatively, the temperature sensors 222 and 224 can be configured to receive and / or provide signals wirelessly from the relay structure. In one example, the sensors can be transducers. In this example, the first temperature sensor 222 is attached to a rear surface 226 of the stationary contact 104 opposite the pad 114. In one example, the contact pad 114 can be configured such that a portion 228 of the pad passes through the contact 104 and the temperature sensor is attached to the rear of the contact pad itself. The second temperature sensor 224 is attached to a portion 230 of the contact at a distance from the pad 114. In one example, the location of the second temperature sensor relative to the first temperature sensor can vary depending on the type of sensor used, the particular mounting point of the first sensor, and the type of relay being used. In one example, when both sensors are attached to the contacts, the distance between the two sensors can be about 1.5 mm to 20 mm, about 2 mm to 18 mm, and about 5 mm to 15 mm measured between the two sensors. In an exemplary embodiment, the second temperature sensor is positioned about 10 mm away from the first temperature sensor.

[0029] 12 illustrates a cutaway top view of an exemplary relay structure 250 somewhat similar to the example shown in FIG. 9, including a housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure shown in FIG. 1E. In this example, the relay structure includes two temperature sensors 222 and 224 positioned within the housing, which may be formed, bonded, or otherwise attached to the structure of one of the contacts 104 and 106, such as by a plasma vapor deposition process. In this example, the temperature sensors 222 and 224 are of a similar form to those described above with respect to the example shown in FIG. 11. In this example, a first temperature sensor 222 is attached to a rear surface 226 of the movable contact 106 opposite the pad 116. In one example, the contact pad 116 can be configured such that a portion 252 of the pad passes through the contact 106 and the temperature sensor is mounted to the rear of the contact pad itself. A second temperature sensor 224 is mounted to a portion 254 of the contact a distance away from the pad 116. In one example, the distance between the first sensor placement location and the second sensor placement location can be within the distance parameters described above with respect to the example shown in FIG.

[0030] FIG. 13 shows a cutaway top view of an exemplary relay structure 260 somewhat similar to the example shown in FIG. 11, including the housing 102, a pair of contacts 104 and 106, and the remaining elements included in the relay structure shown in FIG. 1E. In this example, the relay structure includes three or more temperature sensors. These temperature sensors may be formed, bonded, or otherwise attached to the structure of one of the contacts 104 and 106, such as by a plasma vapor deposition process. In this example, the relay structure includes four temperature sensors 262, 264, 266, and 268 in a similar configuration to those described above with respect to the example shown in FIG. 11. In this example, the first temperature sensor 262 is attached to the rear surface 270 of the stationary contact 104 opposite the pad 114. In one example, the contact pad 114 can be configured such that a portion 272 of the pad penetrates the contact 104, with the first temperature sensor attached to the rear of the contact pad itself. The second temperature sensor 264, the third temperature sensor 266, and the fourth temperature sensor 268 are sequentially positioned at increasing distances from the first sensor 262 on respective portions 274, 276, and 278 of the contact 104, with each of these sensors spaced apart from one another. In one example, the distances between the first and second sensors, the second and third sensors, and the third and fourth sensors can be equal. However, it should be understood that such equal sensor spacing may not be the case depending on factors such as the type of sensors used, e.g., whether the sensors are all the same or different, and the type of relay. Also, while the exemplary relay structure of FIG. 13 shows multiple temperature sensors disposed on stationary contacts, it should be understood that such multiple temperature sensors can also be disposed on movable contacts. In one example, when the multiple sensors are of the same type and equally spaced from one another, the distance between adjacent sensors can be about 0.5 mm to 15 mm, about 1 mm to 10 mm, and about 2 mm to 5 mm. In an exemplary embodiment, the distance between adjacent sensors is about 3 mm, as shown in FIG. 13.

[0031] Although an exemplary relay structure with multiple temperature sensors has been disclosed and illustrated in Figures 11-13, it should be understood that other exemplary relay structure embodiments disclosed herein may include multiple temperature sensors positioned or attached or formed differently than the examples illustrated in Figures 11-13. For example, a relay structure may include multiple temperature sensors positioned along an existing internal structure of the relay structure and / or may be located on a member or substrate, such as a printed circuit board, positioned at a location within the relay structure. All such exemplary embodiments with multiple temperature sensors are intended to fall within the scope of the relay structures disclosed herein.

Claims

1. An outer housing (102); a pair of switchable electrical contacts (104 and 106) disposed within said housing; an element for activating said pair of electrical contacts; a temperature sensing element (182, 192, 222, 262) disposed within said housing adjacent said electrical contacts; Equipped with The electrical contacts include contact pads (114, 116) attached to the electrical contacts, respectively; the contact pads are positioned to contact one another when the electrical contacts are in a closed state; the temperature sensing element is attached to at least one of the contact pads itself; An electromechanical relay (100) comprising a further temperature sensing element (224, 264, 266, 268) disposed within the housing and attached to the electrical contacts at a distance from the temperature sensing element (182, 192, 222, 262).

2. 2. The relay of claim 1, wherein the at least one contact pad is configured such that a portion thereof extends through the electrical contact and the temperature sensing element is attached to the portion of the at least one contact pad itself.

3. 3. The relay of claim 1 or 2, wherein the temperature sensitive element is in electrical contact with an electrical terminal extending from the housing.

4. The relay of claim 1 , wherein the further temperature sensing element (224) is mounted at a distance from the contact pad.

5. The relay of claim 1 , wherein the additional temperature sensitive elements (264, 266, 268) are positioned sequentially on respective portions (274, 276, 278) of the electrical contacts.

6. An outer housing (102); a pair of switchable electrical contacts (104 and 106) disposed within said housing; an element for activating said pair of electrical contacts; a temperature sensing element (118) disposed within the housing adjacent to the electrical contacts; Equipped with The electrical contacts include a first contact (104) having a first contact pad (114) attached thereto and a second contact (106) having a second contact pad (116) attached thereto; the first contact pad and the second contact pad are positioned to contact each other when the electrical contact is in a closed state; the temperature sensing element is positioned along a plane that intersects a longitudinal axis extending along a length of the electrical contact; An electromechanical relay (100), wherein the temperature sensing element is positioned facing both the first contact pad and the second contact pad.

7. The relay of claim 6, wherein the temperature sensitive element (118) is attached to a member (115) mounted within the housing.

8. The relay of claim 6, wherein the temperature sensitive element (118) is disposed along an internal structure (164) of the relay.

9. The relay of claim 8 , wherein the internal structure (164) is adjacent to one or both of the first contact (104) and the second contact (106).

10. A method for determining a temperature in an electromechanical relay (100), comprising:

7. An electromechanical relay according to claim 1 or 6, wherein the temperature sensing element provides an output signal; and and a monitoring step during said operating step, monitoring said output signal to determine said temperature within said housing.

11. 11. The method of claim 10 comprising two or more temperature sensing elements positioned at different locations within the relay, and wherein the monitoring step includes monitoring output signals from the two or more temperature sensing elements.

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