Relay system

Abstract

To provide a relay system capable of quickly dealing with the occurrence of freezing on a contact while suppressing a decrease in the life of the contact.SOLUTION: A relay system (100) includes a relay device (10) having a contact and a drive mechanism that switches the open / closed state of the contact, and a controller (20) that controls the relay device (10). The controller (20) starts the first energization that causes the drive mechanism to generate a driving force in a direction that does not switch the open / closed state of the contact when freezing occurs at the contact.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a relay system.

Background Art

[0002] Patent Document 1 discloses a relay control device that prevents freezing of the contacts of a relay device in advance. After switching the relay device to an open state by stopping energization of the coil, the relay control device continuously supplies a current to the coil that is not large enough to switch the relay device back to a closed state, thereby preventing dew condensation and freezing from occurring on the contacts in advance.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] In the above conventional relay control device, the contact is heated by passing a current that does not switch the open / closed state of the relay device through the coil, so a large amount of heat cannot be applied to the contact at one time. Therefore, with this method, when freezing occurs on the contact, it takes a long time to make the contact usable by thawing. Further, if a large current that switches the open / closed state of the relay device is passed through the coil to perform thawing, the open / closed state of the contact will switch when the ice is thawed. Therefore, there are restrictions on the timing of thawing, and the service life of the contact is reduced.

[0005] An object of the present invention is to provide a relay system that can promptly deal with freezing of contacts while suppressing reduction in the service life of the contacts.

Means for Solving the Problem

[0006] The relay system according to the present invention includes: A relay device having a contact and a drive mechanism for switching the open / closed state of the contact, The relay device is equipped with a controller that controls the relay device, The relay device includes a first coil that generates a driving force to switch the contact from an open state to a closed state, and a second coil that generates a driving force to switch the contact from a closed state to an open state. When freezing occurs on the contacts, the controller initiates a first current supply that generates a driving force in the drive mechanism in a direction that prevents the open or closed state of the contacts from changing. Furthermore, when the contact is in the open state, the first current is current supplied to the second coil. It is characterized by the following. [Effects of the Invention]

[0007] According to the present invention, a large amount of heat can be generated from the drive mechanism without switching the open / closed state of the contacts upon initiation of the first current supply. Therefore, it is possible to quickly address the issue of ice forming on the contacts while suppressing a decrease in the lifespan of the contacts. [Brief explanation of the drawing]

[0008] [Figure 1] This is a configuration diagram showing a relay device according to an embodiment of the present invention. [Figure 2] This figure shows a relay system and power supply device according to an embodiment of the present invention. [Figure 3] This is a diagram showing the de-freezing process performed by the controller. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described in detail below with reference to the drawings. Figure 1 is a configuration diagram showing a relay device according to an embodiment of the present invention. Figure 1 shows a longitudinal cross-sectional view of the relay device 10 cut along the fixed iron core 163.

[0010] The relay device 10 in this embodiment is a latch relay. A latch relay is a relay that requires energization both when switching contacts A11 and A12 from the open state to the closed state and when switching them from the closed state to the open state. In addition, a latch relay is a relay that maintains the open / closed state even when the power is turned off after the switch has occurred.

[0011] As shown in Figure 1, the relay device 10 includes a pair of contacts A11 and A12 that can be switched between a separated state and a contact state, a first terminal and a second terminal (not shown) to which one side of the electrical circuit to be switched on and off is connected, a first conductor 11 that electrically connects contact A11 and the first terminal, and a second conductor 12 that electrically connects contact A12 and the second terminal. Contact A11 is fixed to a part of the first conductor 11, and contact A12 is fixed to a part of the second conductor 12. A part of the second conductor 12 is supported so as to be displaceable via a spring material 165, and this displacement switches the pair of contacts A11 and A12 between a separated state and a contact state.

[0012] The relay device 10 further includes a drive mechanism 16 that brings a pair of contacts A11 and A12 closer together or further apart, a housing 19, and a first temperature sensor 18 that detects the temperature inside the housing 19.

[0013] The drive mechanism 16 includes a first coil 161, a second coil 162, a fixed core 163, a movable core 164, a spring material 165, and a latch mechanism (not shown). The first coil 161 and the second coil 162, when energized, generate a driving force (magnetic force) that displaces the movable core 164 between the fixed core 163 and the movable core 164. The first coil 161, when energized, generates a driving force in the direction that brings contacts A11 and A12 closer together. The second coil 162, when energized, generates a driving force in the direction that separates contacts A11 and A12. The direction of bringing them closer together means the direction that switches contacts A11 and A12 from an open state to a closed state. The direction of separating contacts A11 and A12 means the direction that switches contacts A11 and A12 from a closed state to an open state. The first coil 161 may also be called the closed-side excitation winding. The second coil 162 may also be called the open-side excitation winding. The latch mechanism holds the movable core 164 in two positions: one where contacts A11 and A12 are in contact and another where they are separated.

[0014] The terminals of the first coil 161 and the terminals of the second coil 162 are located on the outside of the housing 19. Current can be supplied to the first coil 161 and the second coil 162 via external terminals.

[0015] The first temperature sensor 18 has a detection unit located inside the housing 19 and outputs a detection signal indicating the detected temperature to the outside of the housing 19. The first temperature sensor 18 may be fixed to the housing 19, for example. The temperature detected by the first temperature sensor 18 is, for example, the temperature of the air inside the housing 19. The temperature detected by the first temperature sensor 18 may also be the temperature of the first conductor 11 to which contact A11 is fixed, or the second conductor to which contact A12 is fixed.

[0016] The housing 19 houses a pair of contacts A11 and A12, a first conductor 11, a second conductor 12, and a drive mechanism 16. The housing 19 may also be configured to be sealed inside. On the outside of the housing 19 are terminals for the first conductor 11 (first terminal), the second conductor 12 (second terminal), the first coil 161, and the second coil 162.

[0017] With the relay device 10 configured as described above, when the first coil 161 is energized while the pair of contacts A11 and A12 are separated, a driving force acts on the movable parts of the movable core 164 and the second conductor 12 in a direction that brings the pair of contacts A11 and A12 closer together. As the movable parts of the movable core 164 and the second conductor 12 are displaced, contacts A11 and A12 come into contact, and the relay device 10 switches to the closed state. At this time, the latch mechanism maintains the position of the movable parts of the movable core 164 and the second conductor 12. Subsequently, even if the energization of the first coil 161 is stopped, the relay device 10 remains in the closed state.

[0018] Furthermore, when the pair of contacts A11 and A12 are in close proximity and current is supplied to the second coil 162, a driving force acts on the movable core 164 and the movable part of the second conductor 12 in a direction that separates the pair of contacts A11 and A12. As the movable parts of the movable core 164 and the second conductor 12 are displaced and contacts A11 and A12 separate, the relay device 10 switches to the open state. At this time, the latch mechanism maintains the position of the movable parts of the movable core 164 and the second conductor 12. Subsequently, even if the current to the second coil 162 is stopped, the relay device 10 remains in the open state.

[0019] (Relay System) Figure 2 is a diagram showing a relay system and a power supply device according to an embodiment of the present invention. The relay system 100 of the present embodiment includes a relay device 10, a controller 20 that controls the relay device 10, and a second temperature sensor 30 that detects an ambient temperature.

[0020] The relay system 100 may be applied to a power supply device 220 of a vehicle 200 such as an EV (Electric Vehicle), an HEV (Hybrid Electric Vehicle), or an engine automobile. The power supply device 220 includes a power supply unit 221 such as a battery, a DC / DC converter, or a generator, a power line 222 that transmits power from the power supply unit 221 to an electrical device 224, and the relay device 10 that opens and closes the electric path of the power line 222.

[0021] The relay device 10 may be disposed in a power source room such as an engine room. In cold seasons, while the temperature of the power source room becomes high due to the driving of the power source, the temperature may drop sharply when the power source is stopped. Furthermore, the temperature may drop below freezing due to a long stoppage of the power source, resulting in a harsh temperature environment. Even if the inside of the relay device 10 placed in a harsh temperature environment is sealed by a housing 19, moisture may permeate into the interior over time. When moisture has permeated into the interior, the temperature increase of the relay device 10 vaporizes the moisture inside the relay device 10. Thereafter, heat is drawn out from the inside of the relay device 10 via the power line 222 having a large heat capacity, and the first conductor 11 and the second conductor 12 decrease in temperature earlier, which may cause dew condensation on the contacts A11 and A12. Then, when the temperature drops below freezing, freezing occurs on the contacts A11 and A12.

[0022] The second temperature sensor 30 is configured to detect the outside air temperature of the vehicle 200 as the ambient temperature. Alternatively, the second temperature sensor 30 may be configured to detect the temperature of air in a space (for example, the power source room) where the relay device 10 is disposed. The second temperature sensor 30 sends a detection signal indicating the detected temperature to the controller 20.

[0023] The controller 20 is an ECU (Electronic Control Unit) and has a memory unit 22 that stores a control program, and controls the relay device 10 according to the control program. The controller 20 may communicate with other ECUs, such as the vehicle 200's controller, and perform control to switch the open / closed state of the relay device 10 based on the requests of the other ECUs. The controller 20 may also be configured to be integrated with other ECUs, such as the vehicle 200's controller.

[0024] Next, the functions of the controller 20 will be described. The controller 20 has the function of switching the open / closed state of the relay device 10 based on a request to switch the open / closed state of the relay device 10. The switching of the open / closed state is performed by energizing the first coil 161 or the second coil 162.

[0025] The controller 20 further has a function to estimate whether or not freezing has occurred at contacts A11 and A12 based on the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 30. The estimation regarding whether or not freezing has occurred includes estimating whether or not freezing has occurred, estimating whether or not there is a possibility of freezing occurring, and estimating whether or not that possibility exceeds a certain threshold. Next, the case in which the first temperature sensor 18 detects the temperature of the air inside the housing 19 and the second temperature sensor 30 detects the ambient temperature will be described. The ambient temperature detected by the second temperature sensor 30 is easily transmitted as the temperature of contacts A11 and A12 via the power line 222. Therefore, the controller 20 can estimate the possibility that condensation may occur due to vaporized moisture inside the housing 19 condensing on contacts A11 and A12, based on the difference between the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 30. This estimation can be made by creating a data table in advance, through simulation or experimentation, that associates the above-mentioned temperature difference and detected temperature values ​​with values ​​indicating the possibility of condensation occurring, and providing this table to the controller 20. Furthermore, the controller 20 can estimate that condensation has occurred, and if the detected temperatures of the first temperature sensor 18 and the second temperature sensor 30 are at temperatures that cause condensation to freeze, it can estimate that freezing may have occurred at contacts A11 and A12.

[0026] The temperatures detected by the first temperature sensor 18 and the second temperature sensor 30 are not limited to the above example. Next, we will describe the case in which the first temperature sensor 18 detects the temperature of the first conductor 11 or the second conductor 12 inside the housing 19, and the second temperature sensor 30 detects the temperature of the air in the power source room. The temperature of the air in the power source room detected by the second temperature sensor 30 is close to the temperature of the air inside the housing 19. Therefore, the controller 20 can estimate from the difference between the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 30 that condensation may occur due to vaporized moisture inside the housing 19 condensing at contacts A11 and A12. If there is a possibility of condensation occurring, and the temperatures detected by the first temperature sensor 18 and the second temperature sensor 30 are temperatures that cause condensation to freeze, the controller 20 can estimate that freezing may have occurred at contacts A11 and A12.

[0027] In addition, the controller 20 may estimate that ice has formed on contacts A11 and A12 if it has performed control to switch the open / closed state of the relay device 10 but the open / closed state has not switched. Whether or not the open / closed state has switched can be determined based on the detected values ​​of voltage, current, etc. of the power line 222. In addition to the above, the controller 20 may also estimate whether or not ice has formed on contacts A11 and A12 by taking into account information on whether or not the temperature detected by the first temperature sensor 18 or the second temperature sensor 30 is a temperature that causes ice.

[0028] The controller 20 also has a function to deal with freezing by applying a first current to the drive mechanism 16 (current to the first coil 161 and the second coil 162) when it is estimated that freezing has occurred at contacts A11 and A12. The first current is applied to the drive mechanism 16 in a direction that does not switch the open or closed state of contacts A11 and A12. By applying the first current, a relatively large current can be passed through the drive mechanism 16 without switching the open or closed state of contacts A11 and A12, generating a large amount of heat (e.g., Joule heat) in the drive mechanism 16. Therefore, the generated heat can warm contacts A11 and A12, and the freezing can be quickly melted.

[0029] Specifically, the first energization corresponds to energizing the second coil 162, which generates a driving force in the direction that separates contacts A11 and A12 when contacts A11 and A12 are in the open state. Also, when contacts A11 and A12 are in the closed state, the first energization corresponds to energizing the first coil 161, which generates a driving force in the direction that brings contacts A11 and A12 closer together. The first energization may also be performed by energizing the first coil 161 and the second coil 162 in parallel. In this case, the drive mechanism 16 generates both a driving force in the direction that separates contacts A11 and A12 and a driving force in the direction that brings them closer together. That is, when contacts A11 and A12 are open, a driving force is generated in the direction that does not switch the open / closed state (the direction that separates them), and when contacts A11 and A12 are closed, a driving force is generated in the direction that does not switch the open / closed state (the direction that brings them closer together). Therefore, even if a large current is applied, the open and closed states of contacts A11 and A12 will not change. Furthermore, if the first coil 161 or the second coil 162 has a drive circuit capable of applying current in the reverse direction, the controller 20 may perform a first energization that generates a driving force in a direction that does not change the open and closed state due to reverse energization.

[0030] <Defreezing process> Next, the de-icing process performed by the controller 20 will be described. Figure 3 is a flowchart showing the de-icing process performed by the controller 20. The de-icing process may be performed at all times while the controller 20 is operating, or it may be performed while the controller 20 is operating throughout the cold season in which freezing may occur. Alternatively, if the timing of the switching of the open / closed state of the relay device 10 can be predicted, the process may be performed immediately before that timing. For example, if the relay device 10 switches to the closed state immediately after the vehicle 200 system starts up, the controller 20 may perform the de-icing process during the period from system startup until the relay device 10 switches to the closed state. Alternatively, if there is a high probability that the relay device 10 will switch to the closed state when the engine restarts after idling stop, the controller 20 may perform the de-icing process during the period from idling stop until the engine restarts.

[0031] When the defreezing process is initiated, the controller 20 obtains the temperatures detected by the first temperature sensor 18 and the second temperature sensor 30 (step S1), and estimates whether or not ice has occurred at contacts A11 and A12 based on these detected temperatures (step S2). Then, it determines whether or not there is a possibility (step S3), and if there is no possibility, the controller 20 repeats the processes of steps S1 to S3.

[0032] On the other hand, if it determines that there is a possibility, the controller 20 determines the open / closed state of the relay device 10 (step S4), and if it is in the open state, it starts energizing the second coil (open-side excitation winding) 162 which generates a driving force in the direction of switching to the open state (step S5). After that, the controller 20 determines whether the temperature detected by the first temperature sensor 18 has exceeded the threshold (step S6), and if NO, it repeats the determination process in step S6. The threshold is set to a value that can melt the ice. Then, if the determination result in step S6 is YES, the controller 20 starts timing and determines whether the time the temperature has exceeded the threshold has been longer than the set time (step S7). Then, if the result is NO, the controller 20 returns to step S6.

[0033] Then, in step S6, if it is determined that the detected temperature is above the threshold, and in step S7, if it is determined that the time the temperature has been above the threshold has exceeded the set time, the controller 20 terminates the power supply (step S11). Through the processes in steps S6 and S7, even if ice had formed on contacts A11 and A12, it is possible to determine with high accuracy and quickly that the ice has melted due to the heat of the second coil 162.

[0034] On the other hand, if the determination process in step S4 determines that the device is in a closed state, the controller 20 starts energizing the first coil (closed-side excitation winding) 161, which generates a driving force in the direction of switching to the closed state (step S8). After that, the controller 20 determines whether the temperature detected by the first temperature sensor 18 has exceeded a threshold (step S9), and if NO, the determination process in step S9 is repeated. The threshold is set to a value that can melt the ice. If the determination result in step S9 is YES, the controller 20 starts timing and determines whether the time the temperature has exceeded the threshold has been greater than or equal to the set time (step S10). If the result is NO, the controller 20 returns to step S9.

[0035] Then, in step S9, if it is determined that the detected temperature is above the threshold, and in step S10, if it is determined that the time the temperature has been above the threshold has exceeded the set time, the controller 20 terminates the power supply (step S11). Through the processes in steps S9 and S10, even if ice had formed on contacts A11 and A12, it is possible to determine with high accuracy and quickly that the ice has melted due to the heat of the first coil 161.

[0036] When the power supply is terminated in step S11, the controller 20 terminates the defreezing process. Alternatively, if the defreezing process is to be performed continuously for a certain period, the controller 20 repeatedly performs the above defreezing process until that period has elapsed.

[0037] The program for the defrosting process described above is stored in a non-transient storage medium (non-transient computer-readable medium), such as the storage unit 22 of the controller 20. The controller 20 may be configured to read a program stored in a portable non-transient storage medium and execute the program. The portable non-transient storage medium described above may store the program for the defrosting process described above.

[0038] As described above, according to the relay system 100 of this embodiment, when the controller 20 estimates that there is a possibility of ice forming on the contacts A11 and A12 of the relay device 10, it initiates a first energization to the drive mechanism 16. The first energization is an energization that generates a driving force in the drive mechanism 16 in a direction that does not switch the open or closed state of contacts A11 and A12. Therefore, the first energization can be performed with a relatively large current, and the first energization can generate a large amount of heat from the drive mechanism 16. Consequently, the ice on contacts A11 and A12 can be quickly melted. Furthermore, even if a large current is passed, the drive mechanism 16 generates a driving force in a direction that does not switch the open or closed state, so when the ice on contacts A11 and A12 melts, the open or closed state of contacts A11 and A12 does not switch. Therefore, constraints on the timing of melting the ice are less likely to occur, and furthermore, the reduction in the lifespan of contacts A11 and A12 can be suppressed.

[0039] In the above embodiment, the controller 20 performs an estimation regarding freezing and then performs the first energization. However, the controller 20 does not necessarily have to perform an estimation regarding freezing. For example, a configuration may be adopted in which a request for the first energization is sent to the controller 20 from an external source when freezing occurs, and the controller 20 starts the first energization based on that request.

[0040] The relay system 100 of this embodiment further includes a first temperature sensor 18 that detects the temperature inside the housing 19, and the controller 20 terminates the first energization based on the temperature detected by the first temperature sensor 18. Therefore, the reliability of the process of releasing the ice from contacts A11 and A12 can be improved by the first energization.

[0041] Furthermore, the relay system 100 of this embodiment includes a second temperature sensor 30 for detecting the ambient temperature. The controller 20 then estimates whether or not ice has formed on contacts A11 and A12 based on the temperature detected by the first temperature sensor 18 and the temperature detected by the second temperature sensor 30. Condensation usually occurs before freezing, and condensation mainly occurs due to a temperature difference between the air temperature and the temperature of the object. Therefore, by estimating based on the two detected temperatures, the controller 20 can estimate with high accuracy whether or not condensation has formed on contacts A11 and A12, and thus can estimate with high accuracy whether or not ice has formed on contacts A11 and A12. This highly accurate estimation reduces the wasteful power consumption that occurs when the first current is applied even though there is no ice, and also reduces the chance of missing the opportunity to address ice that has formed. Therefore, a relay system 100 that is less wasteful and less prone to malfunctions in cold weather can be realized.

[0042] Furthermore, according to this embodiment, the relay device 10 includes a first coil 161 that generates a driving force to switch contacts A11 and A12 from an open state to a closed state, and a second coil 162 that generates a driving force to switch contacts A11 and A12 from a closed state to an open state. When contacts A11 and A12 are in the open state, the first energization is performed by energizing the second coil 162. Therefore, there is no need to add a special drive circuit for performing the first energization, and a configuration in which the controller 20 performs the first energization can be easily realized.

[0043] Furthermore, according to this embodiment, the controller 20 can employ a method of energizing the first coil 161 and the second coil 162 in parallel as the first energization. With this method of energization, heat can be generated from the drive mechanism 16 without switching the open or closed state of contacts A11 and A12 by applying the same energization, whether contacts A11 and A12 are open or closed. Therefore, the controller 20 can omit the process of checking the open or closed state before performing the first energization. Moreover, with this method of energization, a larger overall current can be supplied than when energizing a single coil. Therefore, it becomes possible to deal with freezing more quickly.

[0044] Embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. For example, although the above embodiments show an example in which the relay system is mounted on a vehicle, the relay system according to the present invention is not limited to vehicles and may be incorporated into various devices. For example, the relay system may be incorporated into industrial machinery. Also, although the above embodiments show an example in which the relay device is a latch relay, the relay device may be configured such that the open / closed state is switched by energizing and releasing the coil. In this case, as the first energization, energization flowing in the opposite direction to the energization can be adopted. Even with such a first energization, it is possible to deal with freezing by flowing a large current through the coil without switching the open / closed state of the relay device, which is in an open or closed state by releasing the energization to the coil. Further details shown in the embodiments can be modified as appropriate without departing from the spirit of the invention. [Explanation of symbols]

[0045] 10 Relay device A11, A12 contacts 16 Drive mechanism 18. First temperature sensor 19 cabinets 20 controllers 30. Second temperature sensor 100 Relay System 161 First Coil 162 Second coil 200 vehicles 220 Power Supply 221 Power supply section 222 Power lines 224 Electrical equipment

Claims

1. A relay device having a contact and a drive mechanism for switching the open / closed state of the contact, The relay device is equipped with a controller that controls the relay device, The relay device includes a first coil that generates a driving force to switch the contact from an open state to a closed state, and a second coil that generates a driving force to switch the contact from a closed state to an open state. The relay system is characterized in that, when freezing occurs on the contact, the controller initiates a first current supply that generates a driving force in a direction that does not switch the open or closed state of the contact to the drive mechanism, and when the contact is in the open state, the first current supply is current supply to the second coil.

2. The relay device is A housing that houses the contacts and the drive mechanism, A first temperature sensor for detecting the temperature inside the housing, It further possesses, The aforementioned relay system, It is further equipped with a second temperature sensor that detects ambient temperature, The aforementioned controller, The relay system according to claim 1, characterized in that an estimation is made regarding whether or not ice has formed on the contact based on the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor.

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