Delay power-off protection circuit for post-processing system of passenger car and passenger car

Abstract

The utility model relates to a passenger car post-processing system time-delay power-off protection circuit and a passenger car, and belongs to the technical field of vehicle post-processing system power supply, and the passenger car post-processing system time-delay power-off protection circuit comprises a post-processing system power supply loop used for independently supplying power to a post-processing system, and a normally open contact of a protection relay is connected in series in the post-processing system power supply loop. A coil of the protection relay is connected in series between the manual power switch and the negative electrode of the storage battery, the coil of the protection relay is also connected in series with a normally open contact of the time-delay relay to form a time-delay branch, and the time-delay branch is connected between the positive electrode and the negative electrode of the storage battery; a control coil of the time delay relay is connected with an engine starting signal line, and the engine signal line is electrified when an engine is in a starting state. When the manual power switch is switched off, the time-delay relay enables the coil of the protection relay to be still in a power-on state, and the normally open contact of the protection relay is kept closed to provide working current for the post-processing system, so that the post-processing system is prevented from having a fault due to power failure.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of passenger car aftertreatment system delay power-off protection circuit and passenger car, belong to vehicle aftertreatment system power supply technical field. BACKGROUND

[0002] Under normal circumstances, after engine flameout, the urea pump will continue to work for a period of time, the urea solution remaining in the urea nozzle, pressure pipe and liquid return pipe is pumped back to the urea tank. However, illegal power-off will cause the urea pump and related control unit to lose power, and the emptying operation cannot be completed. The unrecovered urea solution remains in the pipeline, which is easy to crystallize in high or low temperature environment. Crystallization can block the urea nozzle, pipeline and urea pump, causing system failure. For example, after the urea nozzle is blocked, the sprayed urea solution cannot be atomized, further exacerbating the crystallization problem. Crystallization not only blocks the nozzle and pipeline, but also can cause the urea pump to be damaged. In addition, the crystalline substance can enter the catalytic muffler, reducing its catalytic reduction efficiency, and even causing the catalytic muffler to be poisoned. If the urea system cannot work normally due to crystallization blockage, the engine may enter the torque limiting mode, causing the vehicle power to drop. Illegal power-off operation not only increases maintenance cost, but also may face environmental protection penalties due to non-compliance of exhaust emission.

[0003] Currently, the engine of the passenger car industry can only be disconnected from the power supply of the aftertreatment system after 3 minutes of flameout to prevent insufficient urea solution backflow and cause related failures of the aftertreatment system. The existing aftertreatment system power supply is mainly supplied by the storage battery after the handle switch, which will be disconnected at the same time as the driver manually disconnects it. Since it is impossible to ensure that all drivers operate according to the regulations, it is easy to cause failure of the vehicle aftertreatment system, thereby affecting vehicle operation. UTILITY MODEL CONTENTS

[0004] The utility model aims to provide a passenger car aftertreatment system delay power-off protection circuit and passenger car to solve the problem that the aftertreatment system cannot work after the driver manually disconnects the power supply, causing the aftertreatment system to be prone to failure.

[0005] To achieve the above-mentioned purpose, the utility model provides the following scheme:

[0006] A passenger car aftertreatment system delay power-off protection circuit, comprising: an aftertreatment system power supply circuit for independently supplying power to the aftertreatment system, the aftertreatment system power supply circuit has a normally open contact of a protection relay connected in series, the coil of the protection relay is connected in series between a manual power switch and the negative electrode of a storage battery, and the coil of the protection relay is also connected in series with a normally open contact of a delay relay to form a delay branch, the delay branch being connected between the positive and negative electrodes of the storage battery; the control coil of the delay relay is connected to an engine start signal line, and the engine signal line is electrified in the engine start state.

[0007] Further, the positive pole of the battery is connected to the first contact on the side of the positive pole of the relay coil of the protection relay through the manual power switch on the time delay branch, and a reverse prevention diode with a conduction direction from the positive pole of the battery to the first contact is further connected in series between the first contact and the positive pole of the battery on the time delay branch.

[0008] Further, a first fuse is further connected in series in the power supply circuit for the aftertreatment system.

[0009] Further, a second fuse is further connected in series in the time delay branch.

[0010] Further, the time delay power-off protection circuit for the aftertreatment system of the passenger vehicle is further connected with the engine ECU for supplying power to the engine ECU.

[0011] A passenger vehicle comprising a time delay power-off protection circuit for the aftertreatment system of the passenger vehicle, the time delay power-off protection circuit for the aftertreatment system of the passenger vehicle comprising:

[0012] a power supply circuit for independently supplying power to the aftertreatment system, wherein a normally open contact of a protection relay is connected in series in the power supply circuit for the aftertreatment system, a coil of the protection relay is connected in series between a manual power switch and a negative pole of a battery, the coil of the protection relay is further connected in series with a normally open contact of a time delay relay to form a time delay branch, the time delay branch is connected between positive and negative poles of the battery, a control coil of the time delay relay is connected with an engine starting signal line, and the engine signal line is electrified in an engine starting state.

[0013] Further, the positive pole of the battery is connected to the first contact on the side of the positive pole of the relay coil of the protection relay through the manual power switch on the time delay branch, and a reverse prevention diode with a conduction direction from the positive pole of the battery to the first contact is further connected in series between the first contact and the positive pole of the battery on the time delay branch.

[0014] Further, a first fuse is further connected in series in the power supply circuit for the aftertreatment system.

[0015] Further, a second fuse is further connected in series in the time delay branch.

[0016] Further, the time delay power-off protection circuit for the aftertreatment system of the passenger vehicle is further connected with the engine ECU for supplying power to the engine ECU.

[0017] The beneficial effects of this invention are as follows: The automotive aftertreatment system power supply circuit is independently powered, and a normally open contact of a protective relay is connected in series in the automotive aftertreatment system power supply circuit. Both the time-delay branch and the manual power supply circuit are connected to the coil of the protective relay. Utilizing the time-delay disconnection characteristic of the time-delay relay, the coil of the protective relay remains energized even when the manual power switch is turned off (i.e., the driver improperly disconnects the vehicle's power). The normally open contact of the protective relay remains closed, providing operating current to the aftertreatment system until the time-delay relay disconnects, at which point the aftertreatment system stops working. Even if the driver improperly disconnects the vehicle's power, the automotive aftertreatment system will continue to operate, preventing malfunctions due to power outages. Attached Figure Description

[0018] Figure 1 This is a circuit diagram of a delayed power-off protection circuit for passenger vehicles provided by this utility model. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be described in a clear and complete manner below with reference to the accompanying drawings and embodiments.

[0020] The concept of this utility model is as follows: the power supply circuit of the automotive after-treatment system is independently powered, and the power supply circuit of the automotive after-treatment system is connected in series with the normally open contact of the protection relay. The time delay branch and the manual power circuit are both connected to the coil of the protection relay. When the manual power circuit is de-energized (i.e. the driver illegally turns off the car power), the time delay relay branch is de-energized for a delay, while the coil of the protection relay is still energized, and the normally open contact of the protection relay remains closed to supply power to the after-treatment system.

[0021] Example of a delayed power-off protection circuit for a bus after-treatment system:

[0022] like Figure 1 The diagram shows a circuit diagram of a delayed power-off protection circuit for a passenger vehicle. Figure 1 In the circuit, number 1 is a protective relay, number 2 is a manual power switch, number 3 is a time delay relay, number 4 is a diode, number 5 is the first fuse, and number 6 is the second fuse.

[0023] The bus delayed power-off protection circuit includes the after-processing system power supply circuit, the manual power supply circuit, and the delayed branch circuit.

[0024] The after-treatment system power supply circuit includes a protective relay with an independent power supply connection. One end of the normally open contact of the protective relay is connected to the positive terminal of the battery, and the other end is connected to the after-treatment system to supply power.

[0025] The manual power circuit includes a manual power switch. One contact of the manual power switch is connected to the positive terminal of the battery, and the other contact is connected to the negative terminal of the battery through the coil of a protective relay.

[0026] A delay branch is connected between the manual power switch and the protection relay.

[0027] The delay branch includes a delay relay, one end of the coil of the delay relay is connected to the engine starting signal, the other end is connected to the negative pole of the battery, one normally open contact of the delay relay is connected to the positive pole of the battery, and the other normally open contact is connected between the manual power supply and the coil of the protection relay in the manual power supply circuit.

[0028] In order to prevent the current from being too large to burn out the protection relay, as an implementable way, a fuse is connected in series at one end of the protection relay connected to the positive pole of the battery.

[0029] Similarly, in order to prevent the current from being too large to burn out the delay relay, as an implementable way, a fuse is connected in series at one end of the delay relay connected to the positive pole of the battery.

[0030] In order to prevent the current of the manual power supply switch circuit from flowing into the delay branch, as an implementable way, a diode is connected in the delay branch connected to the manual power supply circuit, the direction of the diode is from the delay relay to the manual power supply circuit, which is used to prevent the current of the manual power supply circuit from flowing into the delay branch.

[0031] When the passenger car delay power-off protection circuit supplies power to the automobile aftertreatment system, in order to maximize the use of its energy, as an implementable way, the automobile ECU is also connected with the delay power-off protection circuit, and when the passenger car delay power-off protection circuit supplies power to the aftertreatment system, the automobile ECU can also work with its electric energy.

[0032] Specifically, when the driver does not operate irregularly, the automobile sequentially goes through the following steps from turning on to power-off:

[0033] 1) Insert the key, the manual power supply is closed, but the engine is not started. Specifically, after the manual power supply is closed, the manual power supply circuit is connected, the current flows from the positive pole of the battery to the negative pole of the battery through the coil, the coil is electrified to attract the protection relay, after the protection relay is attracted, the aftertreatment system power supply circuit is electrified, the current flows from the positive pole of the battery to the aftertreatment circuit through the normally open contact of the protection relay, and the aftertreatment circuit is electrified to perform aftertreatment on the automobile.

[0034] 2) Insert the key, close the manual power switch, start the engine. Specifically, after the manual power switch is closed, the manual power circuit is connected, and the current flows from the positive terminal of the battery to the negative terminal of the battery through the coil; at the same time, after the engine is started, the coil of the time delay relay is powered, and after the time delay relay is powered, the normally open contact of the time delay relay is attracted, the time delay branch is powered, and the current flows from the positive terminal of the battery to the negative terminal of the battery through the normally open contact of the time delay relay and the coil of the protection relay. That is, the coil of the protection relay is powered by the manual power circuit and the time delay branch at this time, and after the coil of the protection relay is powered, the normally open contact of the protection relay is attracted, and working current is provided for the post-processing circuit.

[0035] 3) The engine is turned off, the key is not pulled out, and the manual power switch remains closed. Specifically, after the engine is turned off, the time delay relay is powered off, that is, the normally open contact of the time delay relay remains attracted within 3 minutes after the engine signal disappears, that is, the current of the time delay branch still exists within 3 minutes after the engine signal disappears, and flows from the positive terminal of the battery to the negative terminal of the battery through the normally open contact of the time delay relay and the coil of the protection relay; at the same time, since the key is not pulled out, the manual power switch remains closed, and the manual power circuit current also still exists. That is, the coil of the protection relay is still powered by the time delay branch and the manual power circuit as in 2), so that the normally open contact of the protection relay remains attracted. The current of the post-processing system power supply circuit flows from the positive terminal of the battery to the post-processing system through the normally open contact of the protection relay to provide working current for the post-processing system.

[0036] When the driver disconnects the power of the vehicle in violation of the regulations, the above step 3) changes as follows:

[0037] The engine is turned off, the driver pulls out the key in violation of the regulations, and the manual power switch is disconnected. Specifically, since the driver closes the manual power switch in violation of the regulations, the manual power switch circuit current disappears and cannot provide current for the coil of the protection relay, but after the engine is turned off, the time delay relay is powered off, that is, the normally open contact of the time delay relay remains attracted within 3 minutes after the engine signal disappears, that is, the current of the time delay branch still exists within 3 minutes after the engine signal disappears, and flows from the positive terminal of the battery to the negative terminal of the battery through the normally open contact of the time delay relay and the coil of the protection relay; that is, within 3 minutes after the engine signal disappears and the driver closes the manual power switch in violation of the regulations, the time delay branch still provides current for the coil of the protection relay, and the normally open contact of the protection relay also remains attracted within the time that the normally open contact of the time delay relay remains attracted, so that the current of the post-processing system power supply circuit flows from the positive terminal of the battery to the post-processing system through the normally open contact of the protection relay to make it work. At the same time, the time length of the time delay relay can be adjusted artificially to adapt to different vehicle models.

[0038] Passenger car embodiment:

[0039] At present, the engine in the passenger car industry can be disconnected from the power supply of the aftertreatment system after 3 minutes of engine shutdown to prevent insufficient backflow of urea solution and cause related failures of the aftertreatment system. The existing power supply of the aftertreatment system is mostly supplied by a handle switch and a storage battery, and is disconnected at the same time after manual disconnection by the driver, which cannot guarantee that all drivers operate according to the regulations and is prone to cause failures of the vehicle aftertreatment system and further affect the operation of the vehicle.

[0040] In order to overcome the problem that the low-voltage power supply system of the existing passenger car cannot avoid the violation of the regulations by the driver to operate the power handle switch of the vehicle and cause failures of the vehicle aftertreatment system, the utility model provides a passenger car provided with a passenger car delay power-off protection circuit, which does not affect the normal power supply of the vehicle and can prevent the influence of the vehicle aftertreatment system when the driver does not close the power handle switch according to the relevant requirements. The passenger car delay power-off protection circuit has been sufficiently clear in the circuit embodiment, and will not be described here.

[0041] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these examples without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A transit vehicle aftertreatment system delay power-off protection circuit, comprising: The application relates to a passenger car aftertreatment system delay power-off protection circuit, which comprises: An aftertreatment system power supply circuit for independently supplying power to an aftertreatment system, wherein the aftertreatment system power supply circuit is connected in series with the normally open contact of a protection relay, the coil of the protection relay is connected in series between a manual power switch and the negative pole of a storage battery, the coil of the protection relay is also connected in series with the normally open contact of a delay relay to form a delay branch, and the delay branch is connected between the positive pole and the negative pole of the storage battery; the control coil of the delay relay is connected with an engine starting signal line, and the engine signal line is electrified in the engine starting state.

2. The transit vehicle aftertreatment system brownout protection circuit of claim 1, wherein, The positive pole of the storage battery is connected to a first contact on the positive pole side of the protection relay coil in the delay branch through the manual power switch, and a reverse prevention diode with the conduction direction from the positive pole of the storage battery to the first contact is further connected in series between the first contact and the positive pole of the storage battery in the delay branch.

3. The transit vehicle aftertreatment system brownout protection circuit of claim 1, wherein, A first fuse is further connected in series in the aftertreatment system power supply circuit.

4. The transit vehicle aftertreatment system brownout protection circuit of claim 1, wherein, A second fuse is further connected in series in the delay branch.

5. The transit vehicle aftertreatment system brownout protection circuit of claim 1, wherein, The passenger car aftertreatment system delay power-off protection circuit is further connected with an engine ECU for supplying power to the engine ECU.

6. A passenger vehicle characterized by The application relates to a passenger car aftertreatment system delay power-off protection circuit, which comprises: An aftertreatment system power supply circuit for independently supplying power to an aftertreatment system, wherein the aftertreatment system power supply circuit is connected in series with the normally open contact of a protection relay, the coil of the protection relay is connected in series between a manual power switch and the negative pole of a storage battery, the coil of the protection relay is also connected in series with the normally open contact of a delay relay to form a delay branch, and the delay branch is connected between the positive pole and the negative pole of the storage battery; the control coil of the delay relay is connected with an engine starting signal line, and the engine signal line is electrified in the engine starting state.

7. The passenger car of claim 6, wherein, The positive pole of the storage battery is connected to a first contact on the positive pole side of the protection relay coil in the delay branch through the manual power switch, and a reverse prevention diode with the conduction direction from the positive pole of the storage battery to the first contact is further connected in series between the first contact and the positive pole of the storage battery in the delay branch.

8. The passenger car of claim 6, wherein, A first fuse is further connected in series in the aftertreatment system power supply circuit.

9. The passenger car of claim 6, wherein, A second fuse is further connected in series in the delay branch.

10. The passenger car of claim 6, wherein, The passenger car aftertreatment system delay power-off protection circuit is further connected with an engine ECU for supplying power to the engine ECU.

Images