Apparatus and methods related to coolant diverter valves

Abstract

A method and apparatus (1) for fault detection of a coolant diverter valve (4). A coolant diverter valve (4) is arranged in a coolant system to control the flow of coolant from a coolant reservoir (2) to a diesel exhaust fluid tank (3). At least a first sensor (50) is provided for measuring the pressure and / or temperature of the coolant. During operation of the coolant diverter valve (4), the coolant diverter valve (4) is commanded to open by energizing the coolant diverter valve (4), and the coolant diverter valve (4) is commanded to close by de-energizing the coolant diverter valve (4), as needed, from time to time. Based on readings from the first sensor (50), the controller (60) may determine whether the coolant diverter valve (4) fails to close when the coolant diverter valve (4) is powered off.

Description

Technical Field

[0001] The present disclosure relates to an apparatus for controlling the temperature of a diesel exhaust fluid (DEF) in a DEF tank and to a fault detection method of a coolant diverter valve (CDV). Background Art

[0002] It is known to provide a diesel internal combustion engine with a source of diesel exhaust fluid (DEF) for injection into the exhaust system during operation. Typically, the DEF comprises an aqueous solution of urea, and the exhaust system is configured to inject the DEF into the exhaust stream upstream of a selective catalytic reduction (SCR) module. Subsequently, a reaction between the catalyst of the SCR and the DEF converts the NOx component of the exhaust stream into nitrogen and water.

[0003] DEF may be stored in a DEF tank. Under cold conditions, the DEF within the DEF tank may increase in viscosity, become slurried, or even freeze. To prevent this, it is known to pass a heated coolant fluid through a conduit passing through the DEF tank so as to supply thermal energy to the DEF within the DEF tank. In order to prevent the DEF in the DEF tank from overheating, it is important to control the flow of the heated coolant through the DEF tank. To achieve this, it is known to provide a valve, known as a coolant diverter valve (CDV), to control the flow of the heated coolant along the conduit. Typically, such a coolant diverter valve requires an inexpensive and simple design.

[0004] However, the applicant has discovered that such valves may become clogged with debris circulating within the coolant system. Such debris may include, for example, particles such as metal particles, rust particles, flakes detached from engine parts such as the radiator, foundry sand, or foreign matter that enters the coolant system during occasional filling of the coolant fluid. Where the valve is, for example, a 2-way, 2-position solenoid valve, clogging of the valve may be a particular problem, as such valves include orifices and clearances of small size. In the event that the valve is clogged, heated coolant may continue to pass through the DEF tank, causing the DEF to overheat, which in turn may cause the engine to shut down to prevent damage due to the hot DEF. The hot DEF may decompose into ammonia or form deposits, which may penetrate and damage components. Summary of the invention

[0005] An embodiment of the present disclosure provides a method for detecting a fault of a coolant diverter valve, the method comprising:

[0006] A coolant diverter valve is arranged in the coolant system to control the flow of coolant from the coolant reservoir to the diesel exhaust fluid tank;

[0007] providing a first sensor for measuring the pressure and / or temperature of the coolant;

[0008] as needed, from time to time operating the coolant diverter valve by commanding the coolant diverter valve to open by energizing the coolant diverter valve and commanding the coolant diverter valve to close by de-energizing the coolant diverter valve; and

[0009] A determination is made based on a reading from the first sensor whether the coolant diverter valve failed to close when the coolant diverter valve was de-energized.

[0010] Another embodiment of the present disclosure provides a device for controlling the temperature of diesel exhaust fluid in a diesel exhaust fluid tank, the device comprising:

[0011] a coolant reservoir containing a coolant;

[0012] A diesel engine exhaust treatment fluid tank, the diesel engine exhaust treatment fluid tank is used to contain a urea aqueous solution for injection into an exhaust system;

[0013] Coolant diverter valve;

[0014] a coolant line for circulating coolant from the coolant reservoir via the coolant diverter valve and the diesel exhaust fluid tank and returning to the coolant reservoir;

[0015] a first sensor for measuring the pressure and / or temperature of the coolant; and

[0016] A controller configured to:

[0017] commanding the coolant diverter valve to open by energizing the coolant diverter valve, and commanding the coolant diverter valve to close by deenergizing the coolant diverter valve;

[0018] receiving a reading from a first sensor; and

[0019] When the coolant diverter valve is commanded to close, a determination is made based on a reading from the first sensor whether the coolant diverter valve fails to close.

[0020] Another embodiment of the present disclosure provides a method for detecting a fault of a coolant diverter valve, the method comprising:

[0021] A coolant diverter valve is arranged in the coolant system to control the flow of coolant from the coolant reservoir to the diesel exhaust fluid tank;

[0022] as needed, from time to time operating the coolant diverter valve by: commanding the coolant diverter valve to open by energizing the coolant diverter valve, and commanding the coolant diverter valve to close by de-energizing the coolant diverter valve;

[0023] Whether the coolant diverter valve fails to close when the coolant diverter valve is de-energized is determined based on detecting a position of a valve element of the coolant diverter valve based on detecting a position of a solenoid armature of the coolant diverter valve.

[0024] Another embodiment of the present disclosure provides a device for controlling the temperature of diesel exhaust fluid in a diesel exhaust fluid tank, the device comprising:

[0025] a coolant reservoir containing a coolant;

[0026] A diesel engine exhaust treatment fluid tank, the diesel engine exhaust treatment fluid tank is used to contain a urea aqueous solution for injection into an exhaust system;

[0027] a coolant diverter valve including a valve element movable by a solenoid armature;

[0028] a coolant line for circulating coolant from the coolant reservoir via the coolant diverter valve and the diesel exhaust fluid tank and returning to the coolant reservoir;

[0029] A controller configured to:

[0030] commanding the coolant diverter valve to open by energizing the coolant diverter valve, and commanding the coolant diverter valve to close by de-energizing the coolant diverter valve; and

[0031] When the coolant diverter valve is commanded to close, a determination is made as to whether the coolant diverter valve fails to close based on detecting the position of the solenoid armature. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] One or more embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0033] Figure 1 is a schematic diagram of an apparatus including a coolant reservoir connected to a diesel exhaust fluid (DEF) tank via a coolant diverter valve (CDV);

[0034] Figure 2 is through Figure 1 A cross-sectional perspective view of a CDV;

[0035] Figure 3 is a schematic diagram of an embodiment according to the present disclosure, comprising a controller operably connected to a first downstream sensor and a CDV;

[0036] Figure 4 is a schematic diagram of another embodiment according to the present disclosure, comprising a controller operably connected to a first upstream sensor, a second downstream sensor, and a CDV;

[0037] Figure 5 is a schematic diagram of another embodiment according to the present disclosure, comprising a controller operably connected to a first upstream sensor and a CDV;

[0038] Figure 6a is a schematic diagram of a solenoid armature and a solenoid coil of an embodiment of a CDV in an open state; and

[0039] Figure 6b yes Figure 6a Schematic diagram of the CDV's solenoid armature and solenoid coil in the closed state. DETAILED DESCRIPTION

[0040] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by readers in the field to which the claimed subject matter belongs. It should be understood that the above overview and the following examples of the present disclosure are exemplary and illustrative only and do not limit any subject matter claimed.

[0041] The following description is directed to embodiments of the present disclosure. The description of the embodiments is not intended to include all possible embodiments of the present disclosure claimed in the appended claims. Many modifications, improvements, and equivalents not explicitly described in the following embodiments may fall within the scope of the appended claims. Features described as part of one embodiment may be combined with features of one or more other embodiments, unless the context clearly requires otherwise.

[0042] In this specification, the use of the singular includes the plural unless the context clearly dictates otherwise. In this application, the use of "and / or" means "and" as well as "or" unless otherwise stated.

[0043] The present disclosure generally relates to an apparatus 1 comprising a coolant diverter valve (CDV) 4. The apparatus 1 may be coupled to or form part of an engine, such as a diesel internal combustion engine. Figure 1 An example of such a device 1 known in the art is schematically illustrated.

[0044] The device 1 comprises a coolant reservoir 2 including a coolant line outlet port 5; a diesel exhaust fluid (DEF) tank 3 for containing an aqueous urea solution 10 for injection into an exhaust system of an engine; a coolant line 20 for conveying a coolant fluid 7 discharged from the coolant reservoir 2 via the coolant line outlet port 5 to the DEF tank 3 so as to enable heat exchange between the coolant fluid 7 and the aqueous urea solution 10 contained in the DEF tank 3 in use; and a CDV 4 located on the coolant line 20 for controlling the flow of the coolant fluid 7 along the coolant line 20 to the DEF tank 3.

[0045] Heat exchange may be achieved, for example, by passing coolant fluid 7, which has been heated by the engine in use, through the interior of the DEF tank 3, for example through a section of a coiled conduit 22 supplied by a coolant line 20. The coiled conduit 22 may be connected to a coolant return line 21 which may return the coolant fluid 7 directly or indirectly to the coolant reservoir 7.

[0046] It is known to use a solenoid valve as CDV 4. Figure 2 An example of such a CDV 4 is shown by way of example in . The CDV 4 shown is a 2-way, 2-position, normally closed solenoid valve with auxiliary lift. The inlet 30 of the CDV 4 is connected to the inlet section 20A of the coolant line 20. The outlet 31 of the CDV 4 is connected to the outlet section 20B of the coolant line 20. The armature 35 is located within the solenoid coil 36 and is biased downwardly away from the fixed core 40 by a spring 37. A seal 41 is provided at the lower end of the armature 35 for sealing the orifice 39 of the CDV 4. A shuttle rack 38 is captured at the lower end of the armature 35. The shuttle rack 38 also engages with the diaphragm 32 of the CDV 4. When the CDV 4 is closed, the diaphragm 32 sealingly engages against the main valve seat 42. The diaphragm 32 also defines a pilot chamber 34 above the diaphragm 32. A bleed hole 33 is provided in the diaphragm 32 to allow fluid to flow from the inlet 30 into the pilot chamber 34 above the diaphragm 32 when the CDV 4 is closed.

[0047] When the solenoid coil 36 is de-energized, the CDV 4 is closed by the engagement of the seal 41 against the orifice 39 and the engagement of the diaphragm 32 against the main valve seat 42 under the action of the spring 37. At the same time, the pilot chamber 34 is opened to the relatively high pressure of the inlet 30 via the bleed hole 33, so that the fluid pressure in the pilot chamber 34 increases the closing force.

[0048] When the solenoid coil 36 is energized, the armature 35 is lifted, compressing the spring 37, which in turn lifts the diaphragm 32 to a partially open position due to the armature 35 lifting the shuttle 38. The orifice 39 is thereby opened by the disengagement of the seal 41. Since the fluid flows out of the pilot chamber 34 via the orifice 39 faster than the fluid flows into the pilot chamber 34 via the bleed hole 33, the fluid pressure in the pilot chamber 34 is reduced. Therefore, the pressure differential across the diaphragm 32 (higher at the bottom) helps to lift and maintain the diaphragm 32 in its fully open position, in which the diaphragm 32 is unsealed from the main valve seat 42. Therefore, fluid flow from the inlet 30 to the outlet 31 is established. Subsequently, by de-energizing the solenoid coil 36 again, the CDV 4 can be commanded to close.

[0049] Such valves may become clogged, for example, due to debris circulating within the device 1. In particular, because the valve orifice size and clearances are small. For example, the diameter of the orifice 39 may be about 1.0 mm, the diameter of the bleed hole 33 may be about 0.8 mm, and the radial clearance between the armature 35 and the coil 36 may be about 0.25 mm. Clogging of the CDV 4 typically causes the valve to remain open or partially open when it should be closed.

[0050] According to the embodiments of the present disclosure, Figure 3 As illustrated, the device 1 is modified by providing at least a first sensor 50 for measuring the pressure and / or temperature of the coolant and a controller 60 .

[0051] Controller 60 is configured to command CDV 4 to open by energizing CDV 4 and to command CDV 4 to close by de-energizing CDV 4; receive readings from first sensor 50; and when commanding CDV 4 to close, determine whether CDV 4 fails to close based on readings from first sensor 50.

[0052] The first sensor 50 may be located downstream of the CDV 4. Alternatively, the first sensor 50 is located upstream of the CDV 4.

[0053] A second sensor 51 for measuring the pressure and / or temperature of the coolant may be provided. The first sensor 50 may be downstream of the CDV 4 and the second sensor 51 may be upstream of the CDV 4, or vice versa.

[0054] The first sensor 50 may be a temperature sensor, a pressure sensor, or a combined temperature and pressure sensor. The second sensor 51 may be a temperature sensor, a pressure sensor, or a combined temperature and pressure sensor. Examples of suitable temperature sensors include, but are not limited to, thermocouples, such as type K thermocouples. Examples of suitable pressure sensors include, but are not limited to, sensors based on capacitance or strain gauges, such as the 320-3062 pressure sensor from Caterpillar.

[0055] The first sensor 50 and / or the second sensor 51 may be integrated with the CDV 4, i.e., disposed within or directly coupled to the housing of the CDV 4. Alternatively, the first sensor 50 and / or the second sensor 51 may be separate from the CDV 4. In this case, the first sensor 50 and / or the second sensor 51 may be located near the CDV 4, for example, on a portion of the coolant line 20 close to the CDV 4, for example, on or near the inlet section 20A and / or the outlet section 20B of the coolant line 20. Alternatively, the first sensor 50 and / or the second sensor 51 may be located farther from the CDV 4, for example, at a farther point of the coolant line 20.

[0056] The controller 60 may be configured to determine whether the CDV 4 has failed to close based on changes in the temperature and / or pressure of the coolant when the CDV 4 is commanded to close.

[0057] Example 1

[0058] Figure 3 A portion of an example apparatus 1 is illustrated in which a first sensor 50 is located downstream of the CDV 4, in the lead-off section 20B. (However, as described above, the first sensor 50 may be located at a further point along the coolant line.) The first sensor 50 may be a temperature sensor.

[0059] The coolant flowing from the coolant reservoir 2 along the coolant line 20 to the CDV 4 may have a relatively high temperature, such as approximately 80° C. When the CDV 4 is open, the first sensor 50 downstream of the CDV 4 will be exposed to the coolant, and the temperature reading received by the controller 60 from the first sensor 50 will be high (approximately 80° C.). When the CDV 4 is properly closed, the coolant will stop flowing through the first sensor 50. Therefore, the temperature of the coolant near the first sensor 50 will begin to cool toward the ambient temperature of the surrounding environment. However, if the CDV 4 is blocked and fails to close or fails to close completely when the controller 60 issues a command, the coolant will continue to flow through the first sensor 50. Therefore, the temperature reading may not decrease significantly (if the CDV 4 fails to open substantially completely) or may decrease at a slower rate than expected (if the CDV 4 fails to open partially).

[0060] Thus, the controller 60 may be configured to determine that the CDV 4 has failed to close properly when the temperature of the coolant remains above a threshold temperature and / or when the temperature does not decay toward ambient temperature at a rate expected when the CDV 4 is de-energized (eg, the rate at which the temperature decreases is less than a threshold rate).

[0061] Example 2

[0062] Figure 4 A portion of an example apparatus 1 is illustrated in which a first sensor 50 is located downstream of the CDV 4, in the exit section 20B, and a second sensor 51 is located upstream of the CDV 4, in the entry section 20A. (However, as described above, the sensors may be located at further points along the coolant line.) Both the first sensor 50 and the second sensor 51 may be temperature sensors.

[0063] When the CDV 4 is open, the first sensor 50 downstream of the CDV 4 and the second sensor 51 upstream of the CDV 4 will be exposed to the coolant, and the temperature readings received by the controller 60 from both sensors will be high (approximately 80° C.). When the CDV 4 is properly closed, the coolant will stop flowing through the first sensor 50 and the second sensor 51. Therefore, the temperature of the coolant near the first sensor 50 and the second sensor 51 will begin to cool toward the ambient temperature of the surrounding environment. However, if the CDV 4 is blocked and fails to close or fails to close completely when the controller 60 issues a command, the coolant will continue to flow through the first sensor 50 and the second sensor 51. Therefore, the temperature readings may not decrease significantly (if the CDV 4 fails to open substantially completely) or may decrease at a slower rate than expected (if the CDV 4 fails to open partially).

[0064] Thus, the controller 60 may be configured to determine that the CDV 4 has failed to close properly when the temperature of the coolant detected by either or both of the first sensor 50 and the second sensor 51 remains above a threshold temperature and / or when the temperature detected by either or both of the first sensor 50 and the second sensor 51 does not decay toward the ambient temperature at a rate expected when the CDV 4 is powered off (e.g., the rate at which the temperature decreases is less than a threshold rate). When the CDV 4 is properly closed, the temperature reading from the upstream second sensor 51 may decay more slowly than the temperature reading from the first sensor 50. Thus, the controller 60 may also be configured to use this as a basis for determining whether the CDV 4 has failed to open or is partially open.

[0065] Using both the first sensor 50 and the second sensor 51 can increase the reliability and robustness of the determination. In addition, since it can be expected that the temperature responses of the first sensor 50 and the second sensor 51 will be the same or similar to each other, using these two sensors can reduce the time required for the controller 60 to determine a failure to open or a partially open state. Therefore, the deviation (absolute temperature value or relative change in temperature value or rate of temperature change) of the response of one sensor compared to the response of another sensor can allow for a faster determination.

[0066] Example 3

[0067] In this example, again use Figure 4 arrangement, but the first sensor 50 and the second sensor 51 are both pressure sensors.

[0068] When the CDV 4 is open, the first sensor 50 downstream of the CDV 4 and the second sensor 51 upstream of the CDV 4 will be exposed to the flowing coolant. Due to the pressure drop across the CDV 4, the pressure at the location of the upstream second sensor 51 is generally higher than the pressure at the location of the downstream first sensor 50. In addition, there are generally discernible pressure fluctuations due to the flow of coolant.

[0069] When the CDV 4 is properly closed, the coolant will stop flowing through both the first sensor 50 and the second sensor 51. The pressure at the upstream second sensor 51 will experience a pressure rise, while the pressure at the downstream first sensor 50 will experience a pressure drop. In addition, the pressure fluctuations mentioned above will be eliminated or reduced. However, if the CDV 4 is blocked and fails to close or fails to close completely when the controller 60 issues a command, the coolant will continue to flow through the first sensor 50 and the second sensor 51. Therefore, the pressure readings may not increase or decrease as expected.

[0070] Thus, the controller 60 may be configured to determine that the CDV 4 has failed to close properly when one or more of the following conditions occur:

[0071] The pressure at the upstream second sensor 51 fails to rise by a threshold amount;

[0072] The pressure at the downstream first sensor 50 fails to drop by a threshold amount;

[0073] Continue to monitor pressure fluctuations.

[0074] Example 4

[0075] Figure 5 A portion of an example arrangement 1 is illustrated in which a first sensor 50 is located upstream of the CDV 4, in the entry section 20A. (However, as described above, the first sensor 50 may be located at a further point along the coolant line.) The first sensor 50 may be a temperature sensor.

[0076] The coolant flowing from the coolant reservoir 2 along the coolant line 20 to the CDV 4 may have a relatively high temperature, such as approximately 80° C. When the CDV 4 is open, the first sensor 50 upstream of the CDV 4 will be exposed to the coolant, and the temperature reading received by the controller 60 from the first sensor 50 will be high (approximately 80° C.). When the CDV 4 is properly closed, the coolant will stop flowing through the first sensor 50. Therefore, the temperature of the coolant near the first sensor 50 will begin to cool toward the ambient temperature of the surrounding environment. However, if the CDV 4 is blocked and fails to close or fails to close completely when the controller 60 issues a command, the coolant will continue to flow through the first sensor 50. Therefore, the temperature reading may not decrease significantly (if the CDV 4 fails to open substantially completely) or may decrease at a slower rate than expected (if the CDV 4 fails to open partially).

[0077] Thus, the controller 60 may be configured to determine that the CDV 4 has failed to close properly when the temperature of the coolant remains above a threshold temperature and / or when the temperature does not decay toward ambient temperature at a rate expected when the CDV 4 is de-energized (eg, the rate at which the temperature decreases is less than a threshold rate).

[0078] Example 5

[0079] In this example, again use Figure 5 arrangement, but the first sensor 50 is a pressure sensor.

[0080] When the CDV 4 is open, the first sensor 50 upstream of the CDV 4 will be exposed to the flowing coolant. Due to the flow of coolant, there will usually be discernible pressure fluctuations.

[0081] When the CDV 4 is properly closed, coolant will stop flowing through the first sensor 50. The pressure at the upstream first sensor 50 will experience a pressure rise. In addition, the pressure fluctuations mentioned above will be eliminated or reduced. However, if the CDV 4 is blocked and fails to close or fails to close completely when the controller 60 issues a command, coolant will continue to flow through the first sensor 50. Therefore, the pressure reading may not increase as expected.

[0082] Thus, the controller 60 may be configured to determine that the CDV 4 has failed to close properly when one or more of the following conditions occur:

[0083] The pressure at the upstream first sensor 50 fails to rise by a threshold amount;

[0084] Continue to monitor pressure fluctuations.

[0085] In any of the above embodiments, the device 1 may further include a positioner element 70 located on the solenoid armature 35 of the CDV 4. The positioner element 70 may be a magnetic element or a bimetallic element. The positioner element 70 may be fixedly mounted to the surface of the solenoid armature 35, or may be integrated with and / or form a part of the solenoid armature 35. The positioner element 70 may be constrained to move synchronously with the solenoid armature 35.

[0086] The controller 60 may be configured to detect current and / or voltage fluctuations in the solenoid coil 36 of the CDV 4 caused by relative movement of the positioner element 70 and the solenoid coil 36. For example, when the CDV 4 is commanded to close, the controller 60 may determine how far the positioner element 70 (and therefore the solenoid armature 35) has moved downward. This may be used to determine or confirm whether the CDV 4 has been fully closed.

[0087] In some embodiments, the first sensor 50 and / or the second sensor 51 may be omitted and the controller 60 may determine whether the CDV 4 fails to close when the CDV 4 is de-energized based solely on detecting the position of the valve element of the CDV 4 based on detecting the position of the solenoid armature 35 of the CDV using the positioner element 70 .

[0088] In any of the above embodiments of the present disclosure, the CDV may be, for example, a 2-way, 2-position normally closed valve.

[0089] In any embodiments of the present disclosure, the coolant may be, for example, water, ethylene glycol, or a mixture thereof.

[0090] In any embodiments of the present disclosure, the coolant reservoir may be, for example, an engine head coolant tank, or the entirety or a portion of a cylinder block or cylinder head of an engine.

[0091] In any embodiment of the present disclosure, the controller 60 may be operably connected to the CDV 4 and / or the first sensor 50 and / or the second sensor 51 via a wired or wireless connection. The controller 60 may include hardware and / or software. The controller 60 may include a control unit, or may be a computer program running on a dedicated or shared computing resource. The controller 60 may include a single unit, or may be composed of a plurality of subunits that are operably connected. The controller 60 may be located on one processing resource, or may be distributed on spatially separated computing resources. The controller 60 may include one or more programmable and / or non-programmable storage units or subunits. The controller 60 may include a data storage and processing unit or subunit. The controller 60 may include an engine electronic control module (ECM) that is operably connected to the engine or form a part thereof.

[0092] Industrial Applicability

[0093] The present disclosure provides a coolant diverter valve (CDV) fault detection method, the method comprising:

[0094] The CDV is arranged in the coolant system to control the flow of coolant from the coolant reservoir to the diesel exhaust fluid (DEF) tank;

[0095] providing a first sensor for measuring the pressure and / or temperature of the coolant;

[0096] as needed, from time to time operating the CDV by commanding the CDV to open by energizing the CDV and commanding the CDV to close by de-energizing the CDV; and

[0097] A determination is made based on the reading from the first sensor whether the CDV failed to close when power was removed from the CDV.

[0098] Determining that the CDV failed to close properly can result in a fault flag being generated and making the operator (local or remote to the system) aware that the DEF fluid temperature is higher than expected. DEF fluid can be corrosive at higher temperatures and can also decompose more quickly into ammonia, which can permeate through components and damage circuits. They can also result in deposits that can damage components. Therefore, it is desirable to diagnose a faulty CDV valve as quickly as possible.

[0099] The first sensor may measure the pressure and / or temperature of the coolant upstream of the CDV. Alternatively, the first sensor may measure the pressure and / or temperature of the coolant downstream of the CDV.

[0100] The first sensor may measure the temperature of the coolant, and the controller may determine that the CDV has failed to close based on determining that the temperature of the coolant remains above a threshold temperature and / or is not decaying toward ambient temperature at a rate expected when the CDV is powered off.

[0101] The first sensor may measure the pressure of the coolant, and the controller may determine whether the CDV failed to close based on whether an expected pressure change occurs when the CDV is de-energized.

[0102] A second sensor for measuring the pressure and / or temperature of the coolant may be provided, one of the first sensor and the second sensor being upstream of the CDV, and the other of the first sensor and the second sensor being downstream of the CDV.

[0103] A controller may be provided to control the operation of the CDV.

[0104] The CDV may comprise a 2-way, 2-position normally closed valve.

[0105] A position of a valve element of the CDV may be detected, wherein the controller may determine or confirm that the CDV failed to close when the CDV was de-energized based on the detected position of the valve element.

[0106] The position of the valve element can be detected by sensing the position of the solenoid armature of the CDV.

[0107] The positioner element may be disposed on the solenoid armature for detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the CDV.

[0108] The present disclosure further provides an apparatus for controlling the temperature of a diesel exhaust fluid (DEF) in a DEF tank, the apparatus comprising:

[0109] a coolant reservoir containing a coolant;

[0110] a DEF tank for containing an aqueous urea solution for injection into the exhaust system;

[0111] Coolant diverter valve (CDV);

[0112] a coolant line for circulating coolant from the coolant reservoir, through the CDV and the DEF tank, and back to the coolant reservoir;

[0113] a first sensor for measuring the pressure and / or temperature of the coolant; and

[0114] A controller configured to:

[0115] commanding the CDV to open by energizing the CDV, and commanding the CDV to close by de-energizing the CDV;

[0116] receiving a reading from a first sensor; and

[0117] When the CDV is commanded to close, a determination is made based on a reading from the first sensor whether the CDV fails to close.

[0118] The first sensor may be located upstream of the CDV. Alternatively, the first sensor may be located downstream of the CDV.

[0119] The first sensor may be a temperature sensor, and the controller may be configured to determine that the CDV has failed to close based on determining that the temperature of the coolant remains above a threshold temperature and / or does not decay toward ambient temperature at a rate expected when the CDV is powered off.

[0120] The first sensor may be a pressure sensor, and the controller may be configured to determine whether the CDV failed to close based on whether an expected pressure change occurs when the CDV is de-energized.

[0121] The apparatus may further include a second sensor for measuring the pressure and / or temperature of the coolant, one of the first sensor and the second sensor being upstream of the CDV, and the other of the first sensor and the second sensor being downstream of the CDV.

[0122] The coolant reservoir may be an engine head coolant tank, or the entirety or a portion of the engine's cylinder block or cylinder head.

[0123] The CDV may comprise a 2-way, 2-position normally closed valve.

[0124] The apparatus may further include providing a positioner element on a solenoid armature of the CDV, and detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the CDV.

[0125] The present disclosure also provides a coolant diverter valve (CDV) fault detection method, the method comprising:

[0126] The CDV is arranged in the coolant system to control the flow of coolant from the coolant reservoir to the diesel exhaust fluid (DEF) tank;

[0127] As needed, from time to time, operating the CDV by: commanding the CDV to open by energizing the CDV, and commanding the CDV to close by de-energizing the CDV;

[0128] Whether the CDV fails to close when the CDV is de-energized is determined based on detecting a position of a valve element of the CDV based on detecting a position of a solenoid armature of the CDV.

[0129] The method may further include providing a positioner element on the solenoid armature and detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the CDV.

[0130] The locator element can be a magnetic element or a bimetallic element.

[0131] The CDV may comprise a 2-way, 2-position normally closed valve.

[0132] The present disclosure further provides an apparatus for controlling the temperature of a diesel exhaust fluid (DEF) in a DEF tank, the apparatus comprising:

[0133] a coolant reservoir containing a coolant;

[0134] a DEF tank for containing an aqueous urea solution for injection into the exhaust system;

[0135] a coolant diverter valve (CDV) including a valve element movable by a solenoid armature;

[0136] a coolant line for circulating coolant from the coolant reservoir, through the CDV and the DEF tank, and back to the coolant reservoir;

[0137] A controller configured to:

[0138] commanding the CDV to open by energizing the CDV, and commanding the CDV to close by de-energizing the CDV; and

[0139] When the CDV is commanded to close, a determination is made as to whether the CDV has failed to close based on detecting the position of the solenoid armature.

[0140] The apparatus may further include providing a positioner element on the solenoid armature and detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the CDV.

[0141] The locator element can be a magnetic element or a bimetallic element.

[0142] The CDV may comprise a 2-way, 2-position normally closed valve.

[0143] The device is applied to an engine, preferably a diesel internal combustion engine, and in particular a diesel internal combustion engine storing DEF in a DEF tank.

[0144] It should be understood that at least some of the drawings and descriptions of the present disclosure have been simplified to focus on elements relevant to a clear understanding of the present disclosure, while other elements that may also be needed as will be understood by those skilled in the art have been eliminated for the purpose of clarity. Because these elements are well known to those skilled in the art and because they do not necessarily contribute to a better understanding of the present disclosure, descriptions of these elements are not provided herein.

Claims

1. A method for detecting a fault of a coolant diverter valve, the method comprising: The coolant diverter valve is arranged in a coolant system to control the flow of coolant from a coolant reservoir to a diesel exhaust fluid tank; providing a first sensor for measuring the pressure and / or temperature of the coolant; as needed, from time to time operating the coolant diverter valve by: commanding the coolant diverter valve to open by energizing the coolant diverter valve, and commanding the coolant diverter valve to close by de-energizing the coolant diverter valve; as well as A determination is made based on a reading from the first sensor whether the coolant diverter valve fails to close when the coolant diverter valve is de-energized.

2. The method according to claim 1, wherein the first sensor measures the pressure and / or temperature of the coolant upstream of the coolant diverter valve; or wherein the first sensor measures the pressure and / or temperature of the coolant downstream of the coolant diverter valve.

3. The method of claim 1 , wherein the first sensor measures the temperature of the coolant, and the controller determines that the coolant diverter valve has failed to close based on determining that the temperature of the coolant remains above a threshold temperature and / or does not decay toward an ambient temperature at a rate expected when the coolant diverter valve is de-energized. 4 . The method of claim 1 , wherein the first sensor measures the pressure of the coolant, and the controller determines whether the coolant diverter valve fails to close based on whether an expected pressure change occurs when the coolant diverter valve is de-energized.

5. The method of claim 1 , further comprising providing a second sensor for measuring the pressure and / or temperature of the coolant, one of the first sensor and the second sensor being upstream of the coolant diverter valve, and the other of the first sensor and the second sensor being downstream of the coolant diverter valve.

6. The method of claim 1 further comprising providing a controller to control operation of the coolant diverter valve.

7. The method of claim 1, wherein the coolant diverter valve comprises a 2-way, 2-position normally closed valve.

8. The method of claim 1, further comprising detecting a position of a valve element of the coolant diverter valve, wherein the controller determines or confirms that the coolant diverter valve fails to close when the coolant diverter valve is de-energized based on the detected position of the valve element. 9 . The method of claim 8 , wherein the position of the valve element is detected by detecting a position of a solenoid armature of the coolant diverter valve.

10. The method of claim 9, further comprising providing a positioner element on the solenoid armature and detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the coolant diverter valve.

11. A device for controlling the temperature of diesel exhaust fluid in a diesel exhaust fluid tank, the device comprising: a coolant reservoir containing a coolant; A diesel engine exhaust treatment fluid tank, the diesel engine exhaust treatment fluid tank is used to contain a urea aqueous solution for injection into an exhaust system; Coolant diverter valve; a coolant line for circulating the coolant from the coolant reservoir via the coolant diverter valve and the diesel exhaust fluid tank and returning to the coolant reservoir; a first sensor, the first sensor being used to measure the pressure and / or temperature of the coolant; as well as A controller, the controller being configured to: commanding the coolant diverter valve to open by energizing the coolant diverter valve, and commanding the coolant diverter valve to close by de-energizing the coolant diverter valve; receiving a reading from said first sensor; as well as When the coolant diverter valve is commanded to close, a determination is made based on the reading from the first sensor whether the coolant diverter valve fails to close. 12 . The apparatus of claim 11 , wherein the first sensor is located upstream of the coolant diverter valve; or wherein the first sensor is located downstream of the coolant diverter valve.

13. The apparatus of claim 11, wherein the first sensor is a temperature sensor, and the controller is configured to determine that the coolant diverter valve has failed to close based on determining that the temperature of the coolant remains above a threshold temperature and / or does not decay toward an ambient temperature at a rate expected when the coolant diverter valve is de-energized.

14. The apparatus of claim 11, wherein the first sensor is a pressure sensor, and the controller is configured to determine whether the coolant diverter valve fails to close based on whether an expected pressure change occurs when the coolant diverter valve is de-energized.

15. The device according to claim 11, further comprising a second sensor for measuring the pressure and / or temperature of the coolant, one of the first sensor and the second sensor being upstream of the coolant diverter valve, and the other of the first sensor and the second sensor being downstream of the coolant diverter valve.

16. The apparatus of claim 11, wherein the coolant reservoir is an engine head coolant tank, or the entirety or a portion of a cylinder block or cylinder head of an engine.

17. The apparatus of claim 11, wherein the coolant diverter valve comprises a 2-way, 2-position normally closed valve.

18. The apparatus of claim 11, further comprising providing a positioner element on a solenoid armature of the coolant diverter valve, and detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the coolant diverter valve.

19. A device for controlling the temperature of diesel exhaust fluid in a diesel exhaust fluid tank, the device comprising: a coolant reservoir containing a coolant; A diesel engine exhaust treatment fluid tank, the diesel engine exhaust treatment fluid tank is used to contain a urea aqueous solution for injection into an exhaust system; a coolant diverter valve including a valve element movable by a solenoid armature; a coolant line for circulating the coolant from the coolant reservoir via the coolant diverter valve and the diesel exhaust fluid tank and returning to the coolant reservoir; A controller, the controller being configured to: commanding the coolant diverter valve to open by energizing the coolant diverter valve, and commanding the coolant diverter valve to close by de-energizing the coolant diverter valve; and When the coolant diverter valve is commanded to close, a determination is made as to whether the coolant diverter valve fails to close based on detecting a position of the solenoid armature.

20. The apparatus of claim 19, further comprising providing a positioner element on the solenoid armature, and detecting current and / or voltage fluctuations in the solenoid coil caused by relative movement of the positioner element and the solenoid coil of the coolant diverter valve; and optionally wherein the locator element is a magnetic element or a bimetallic element; And / or optionally wherein the coolant diverter valve comprises a 2-way, 2-position normally closed valve.

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