阅读说明：本技术 管路诊断方法及发动机曲轴箱通风系统管路故障诊断方法 (Pipeline diagnostic method and engine crankshaft ventilation system circuit failure diagnostic method ) 是由 潘俊 孔德立 刘思 郭石磊 黄跃 于 2018-05-23 设计创作，主要内容包括：本发明公开了一种管路诊断方法,用于诊断管路的状态,包括：在待诊断管路的表面形成诊断导线；将所述诊断导线接入一检测电路中；通过所述检测电路检测所述诊断导线的电连接状态；以及根据所述诊断导线的电连接状态判定待诊断管路的状态。本发明利用电路连通性判定、诊断管路的状态,能及时发现管路的破损故障,判定过程和算法简单,同时诊断的灵敏度高。进一步地,本发明还公开了一种发动机曲轴箱通风系统管路故障诊断方法,利用发动机自带的电控单元构建检测电路,通过检测诊断导线与转接导电插头所构成导线的电连接状态,能有效诊断通风管路的破损或者断开故障,同时精简了诊断装置与结构,降低了诊断成本。(The invention discloses a kind of pipeline diagnostic methods, for diagnosing the state of pipeline, comprising: form diagnosis conducting wire on the surface of pipeline to be diagnosed；The diagnosis conducting wire is accessed in a detection circuit；The status of electrically connecting of the diagnosis conducting wire is detected by the detection circuit；And the state of pipeline to be diagnosed is determined according to the status of electrically connecting of the diagnosis conducting wire.The present invention can have found the breakage failure of pipeline using the state of circuit communication sex determination, diagnosis pipeline in time, and decision process and algorithm are simple, while the high sensitivity diagnosed.Further, the invention also discloses a kind of engine crankshaft ventilation system circuit failure diagnostic methods, detection circuit is constructed using the electronic control unit that engine carries, pass through the status of electrically connecting of checkout and diagnosis conducting wire and switching the constituted conducting wire of conductive plug, the breakage of energy efficient diagnosis air pipeline disconnects failure, diagnostic device and structure have been simplified simultaneously, has reduced diagnosis cost.)

1. a kind of pipeline diagnostic method, for diagnosing the state of pipeline characterized by comprising

Diagnosis conducting wire is formed on the surface of pipeline to be diagnosed；

The diagnosis conducting wire is accessed in a detection circuit；

The status of electrically connecting of the diagnosis conducting wire is detected by the detection circuit；And

The state of pipeline to be diagnosed is determined according to the status of electrically connecting of the diagnosis conducting wire.

2. pipeline diagnostic method as described in claim 1, which is characterized in that the diagnosis conducting wire is plated in the outer of pipeline to be diagnosed Surface.

3. pipeline diagnostic method as claimed in claim 1 or 2, which is characterized in that the diagnosis conducting wire is S-type or W type is distributed In on the surface of pipeline to be diagnosed.

4. pipeline diagnostic method as claimed in claim 2, which is characterized in that detect the diagnosis by the detection circuit and lead The status of electrically connecting of line determines whether pipeline to be diagnosed has damaging problem according to the status of electrically connecting of the diagnosis conducting wire.

5. pipeline diagnostic method as claimed in claim 1 or 2, which is characterized in that the both ends of pipeline to be diagnosed are equipped with switching Conductive plug, the diagnosis conducting wire are accessed in the detection circuit by switching conductive plug.

6. pipeline diagnostic method as claimed in claim 5, which is characterized in that detect the diagnosis by the detection circuit and lead The status of electrically connecting for the conducting wire that line and the switching conductive plug are constituted, determines that pipeline to be diagnosed is according to the testing result No breakage is disconnected with the switching conductive plug.

7. a kind of diagnostic method of engine crankshaft ventilation system circuit failure characterized by comprising

Two diagnosis conducting wires separated from each other are formed on the surface of pipeline to be diagnosed, the both ends of the diagnosis conducting wire are distributed in follow-up On the both ends of disconnected pipeline；

One diagnosis conducting wire is disconnected, interface A and B is formed in gap, accesses engine electric-controlled list from the gap Member, interface A connect the power supply and digital-to-analogue thief hatch of the engine electric-controlled unit, and interface B connection is described engine electric-controlled The ground line of unit；

Pipeline to be diagnosed is accessed in crankcase ventilation system by switching conductive plug, two diagnosis conducting wires pass through described Conductive plug of transferring constitutes electrical connection, and forms a galvanic circle with the power supply；

Pass through the voltage-to-ground value of the real-time acquisition interface A of the digital-to-analogue thief hatch；

The on off operating mode of the galvanic circle is judged according to the voltage-to-ground value of interface A, and according to the on-off of the galvanic circle State determines the state of pipeline to be diagnosed.

8. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 7, which is characterized in that using electricity Plating method forms two diagnosis conducting wires on the surface of pipeline to be diagnosed.

9. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 7 or 8, which is characterized in that two On the diagnosis S-type outer surface for being evenly distributed on pipeline to be diagnosed of conducting wire described in item.

10. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 9, which is characterized in that connecing Mouthful A and B locates a piece conducting wire of each extraction, the conducting wire of interface A extraction respectively with the power supply sum number of the engine electric-controlled unit Mould thief hatch is connected, and the conducting wire that interface B is drawn is connected with the ground line of the engine electric-controlled unit.

11. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 10, which is characterized in that described Switching conductive plug be hollow structure, the both ends of pipeline to be diagnosed respectively pass through the switching conductive plug respectively with crankcase The air inlet pipe of ventilating system is connected to gs-oil separator.

12. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 11, which is characterized in that described The inner surface of switching conductive plug is metal material, and two diagnosis conducting wires and the power supply pass through two switchings Conductive plug connection conducting, forms a galvanic circle.

13. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 12, which is characterized in that described The on off operating mode of the galvanic circle is judged according to the voltage-to-ground value of interface A, and according to the on off operating mode of the galvanic circle The step of determining the state of pipeline to be diagnosed include:

The size for comparing real-time the voltage-to-ground value and set target value of interface A, judges the on off operating mode of the galvanic circle；

The state of pipeline to be diagnosed is determined according to the on off operating mode of the galvanic circle, if the galvanic circle disconnects, follow-up There are failures for disconnected pipeline, that is, pipeline to be diagnosed generates pipeline damaged or to be diagnosed and the switching conductive plug disconnects.

14. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 13, which is characterized in that institute The voltage-to-ground value of the voltage and the galvanic circle on state lower interface A of stating power supply is averaging, if in the hope of it is flat Mean value is the set target value, then the size of relatively real-time the voltage-to-ground value and set target value of interface A, judges institute The step of stating the on off operating mode of galvanic circle include:

If the real-time voltage-to-ground value of interface A is more than or equal to the set target value, the galvanic circle is disconnected；

If the real-time voltage-to-ground value of interface A is less than the set target value, the galvanic circle conducting.

15. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 14, which is characterized in that pass through The digital-to-analogue thief hatch acquisition is calculated the voltage-to-ground for obtaining the galvanic circle on state lower interface A by relevant parameter Value.

16. engine crankshaft ventilation system circuit failure diagnostic method as claimed in claim 13, which is characterized in that if institute Galvanic circle conducting is stated, then pipeline normally to be diagnosed.

Technical field

The present invention relates to engine monitoring technical fields, more particularly, to a kind of pipeline diagnostic method and engine crankcase Ventilating system circuit failure diagnostic method.

Background technique

In the course of work of internal combustion engine, the unburned gas in cylinder can be scurried by the gap between piston and cylinder jacket In crankcase, to prevent the gas leakage for scurrying into crankcase from causing environmental pollution, Modern Internal-Combustion Engine crankcase ventilation into atmosphere System is designed as closed system.

As shown in Figure 1, the crankcase ventilation system of the engine with supercharger nowadays generallyd use includes high load capacity air pipeline 10 and underload air pipeline 12.When engine operates in high load capacity operating condition, air inlet pipeline after air filter 1 there are negative pressure, Gas blowby in crankcase 8 can be sucked in air inlet pipeline by high load capacity air pipeline 10；When engine operates in underload work When condition, there are negative pressure in the air inlet pipeline after air throttle 5, can inhale the gas blowby in crankcase 8 by underload air pipeline 12 Enter in air inlet pipeline.

Inevitably, due to high load capacity air pipeline 10 and underload air pipeline 12 be connect gs-oil separator with into Between air pipe, structural stability is not strong, when have disconnection failure so that crankcase gas blowby is leaked in atmosphere, pollute environment. Therefore, national emission regulation demands automobile factory must strictly monitor crankcase ventilation system air pipeline and disconnect failure, prevent Only crankcase gas blowby is caused to be leaked in atmosphere because air pipeline disconnects.

And existing monitoring technology scheme mainly acquires real-time pressure or air inflow by sensor, and counts with simulation Calculation value, threshold value comparison judge air pipeline with the presence or absence of leakage problem according to the deviation of actual value and threshold value.But inventor studies It was found that there are following Railway Projects for this kind of monitoring technology scheme: needing by sensor, higher cost；It needs largely to simulate It calculates, diagnostic method is more complicated；When air pipeline leaks, the actual deviation of pressure or air inflow is smaller, the differentiation of failure Degree is not high, i.e. the sensitivity of diagnostic method is lower.

Therefore, find it is a kind of it is at low cost, method is simple, high sensitivity air pipeline leakage fault detection method is current Urgent problem to be solved.

Summary of the invention

One of the objects of the present invention is to provide a kind of pipeline diagnostic methods, with Cultivation principle, and improve failure and examine Disconnected sensitivity.

In order to achieve the above object, the present invention provides a kind of pipeline diagnostic methods wraps for diagnosing the state of pipeline It includes:

Diagnosis conducting wire is formed on the surface of pipeline to be diagnosed；

The diagnosis conducting wire is accessed in a detection circuit；

The status of electrically connecting of the diagnosis conducting wire is detected by the detection circuit；And

The state of pipeline to be diagnosed is determined according to the status of electrically connecting of the diagnosis conducting wire.

Optionally, the diagnosis conducting wire is plated in the outer surface of pipeline to be diagnosed.

Optionally, the diagnosis conducting wire is S-type or W type is distributed on the surface of pipeline to be diagnosed.

Optionally, the status of electrically connecting that the diagnosis conducting wire is detected by the detection circuit, according to the diagnosis conducting wire Status of electrically connecting determine whether pipeline to be diagnosed has damaging problem.

Optionally, the both ends of pipeline to be diagnosed are equipped with switching conductive plug, and the diagnosis conducting wire is inserted by the way that switching is conductive Head accesses in the detection circuit.

Optionally, the conducting wire that the diagnosis conducting wire and the switching conductive plug are constituted is detected by the detection circuit Status of electrically connecting, determine whether pipeline to be diagnosed damaged or breaks with the switching conductive plug according to the testing result It opens.

Another object of the present invention is to provide a kind of diagnostic method of engine crankshaft ventilation system circuit failure, In While improving sensitivity of fault diagnosis, the diagnosis cost of failure is reduced.

In order to achieve the above object, the present invention also provides a kind of engine crankshaft ventilation system circuit failure diagnosis sides Method, comprising:

Two diagnosis conducting wires separated from each other are formed on the surface of pipeline to be diagnosed, the both ends of the diagnosis conducting wire are distributed in On the both ends of pipeline to be diagnosed；

One diagnosis conducting wire is disconnected, forms interface A and B in gap, starts electromechanics from gap access Unit is controlled, interface A connects the power supply and digital-to-analogue thief hatch of the engine electric-controlled unit, the interface B connection engine The ground line of electronic control unit；

Pipeline to be diagnosed is accessed in crankcase ventilation system by switching conductive plug, two diagnosis conducting wires pass through The switching conductive plug constitutes electrical connection, and forms a galvanic circle with the power supply；

Pass through the voltage-to-ground value of the real-time acquisition interface A of the digital-to-analogue thief hatch；

The on off operating mode of the galvanic circle is judged according to the voltage-to-ground value of interface A, and according to the galvanic circle On off operating mode determines the state of pipeline to be diagnosed.

Optionally, two diagnosis conducting wires are formed on the surface of pipeline to be diagnosed using galvanoplastic.

Optionally, on two S-type outer surfaces for being evenly distributed on pipeline to be diagnosed of the diagnosis conducting wire.

Optionally, a piece conducting wire of each extraction at interface A and B, interface A draw conducting wire respectively with it is described engine electric-controlled The power supply of unit is connected with digital-to-analogue thief hatch, the ground line phase of conducting wire and the engine electric-controlled unit that interface B is drawn Even.

Optionally, the switching conductive plug is hollow structure, and the both ends of pipeline to be diagnosed respectively pass through the switching Conductive plug is connected to the air inlet pipe of crankcase ventilation system and gs-oil separator respectively.

Optionally, the inner surface of the switching conductive plug is metal material, two diagnosis conducting wires and the power supply Power supply forms a galvanic circle by two switching conductive plug connection conductings.

Optionally, the on off operating mode that the galvanic circle is judged according to the voltage-to-ground value of interface A, and according to described The on off operating mode of galvanic circle determines that the step of state of pipeline to be diagnosed includes:

The size for comparing real-time the voltage-to-ground value and set target value of interface A, judges the on-off shape of the galvanic circle State；

The state of pipeline to be diagnosed is determined according to the on off operating mode of the galvanic circle, if the galvanic circle disconnects, There are failures for pipeline to be diagnosed, that is, pipeline to be diagnosed generates pipeline damaged or to be diagnosed and the switching conductive plug disconnects.

Optionally, to the voltage-to-ground value of the voltage of the power supply and the galvanic circle on state lower interface A Be averaging, if in the hope of average value be the set target value, it is described relatively interface A real-time voltage-to-ground value and setting The size of target value, the step of judging the on off operating mode of the galvanic circle include:

If the real-time voltage-to-ground value of interface A is more than or equal to the set target value, the galvanic circle is disconnected；

If the real-time voltage-to-ground value of interface A is less than the set target value, the galvanic circle conducting.

Optionally, it acquires by the digital-to-analogue thief hatch or the acquisition galvanic circle is calculated by relevant parameter and shape is connected The voltage-to-ground value of state lower interface A.

Optionally, if the galvanic circle is connected, pipeline normally to be diagnosed.

Compared with prior art, at least there is following advantages in the present invention:

(1), pipeline diagnostic method provided by the invention is formed in the electricity wait diagnose the diagnosis conducting wire on pipeline by detection Connection status whether there is damaging problem to monitor pipeline to be diagnosed, and improves the sensitivity of fault diagnosis and algorithm is relatively simple It is single；

(2), the present invention is equipped with switching conductive plug at pipeline both ends to be diagnosed, and diagnosis conducting wire passes through switching conductive plug Detection circuit for access can effectively detect the on off operating mode for the conducting wire that diagnosis conducting wire and switching conductive plug are constituted, Jin Erneng It deduces the breakage of pipeline to be diagnosed or disconnects failure；

(3), engine crankshaft ventilation system circuit failure diagnostic method of the invention is carried automatically controlled using engine Unit come detect two diagnosis conducting wires and transfer the constituted conducting wire of conductive plug on off operating modes, the on-off of the conducting wire can be passed through Judge the breakage of pipeline to be diagnosed or disconnects failure, it is included using engine while improving sensitivity of fault diagnosis Electronic control unit as detection circuit, simplified diagnostic device and diagnosis algorithm, reduced diagnosis cost.

Detailed description of the invention

Fig. 1 is engine with supercharger crankcase ventilation system structural schematic diagram；

Fig. 2 is the step schematic diagram of the pipeline diagnostic method of one embodiment of the invention；

Fig. 3 is the schematic diagram of deagnostic structure used in the pipeline diagnostic method of one embodiment of the invention；

Fig. 4 is electrical block diagram used in the pipeline diagnostic method of one embodiment of the invention；

Fig. 5 is the equivalent circuit diagram of circuit structure used in the pipeline diagnostic method of one embodiment of the invention；

Fig. 6 is the diagnostic flow chart of the pipeline diagnostic method of one embodiment of the invention；

In figure, 1- air filter, 2- booster, 3- intercooler, 4- air inlet pipeline, 5- air throttle, 6- air inlet pressure sensor, 7- Inlet manifold, 8- crankcase, 9- gs-oil separator, 10- high load capacity air pipeline, 11- gs-oil separator, the ventilation of 12- underload Pipeline, 13-PCV valve, 14- diagnose conducting wire, and 141- first diagnoses conducting wire, and 141a- first diagnoses the first end point of conducting wire, 141b- Second endpoint of the first diagnosis conducting wire, 142- second opinion conducting wire, the first end point of 142a- second opinion conducting wire, 142b- second Diagnose the second endpoint of conducting wire, 15- first transfers conductive plug, and 16- second transfers conductive plug, 17- connecting wire, 17a- the One connecting wire, the second connecting wire of 17b-, 18- electronic control unit, the first pin of 18a- electronic control unit, 18b- electronic control unit Second pin, 19- first diagnose the series equivalent resistance R of conducting wire and second opinion conducting wire₂。

Specific embodiment

A specific embodiment of the invention is described in more detail below in conjunction with schematic diagram.According to following description and Claims, advantages and features of the invention will become apparent from.It should be noted that attached drawing is all made of very simplified form and Using non-accurate ratio, only for the purpose of facilitating and clarifying the purpose of the embodiments of the invention.

As shown in Figure 1, the crankcase ventilation system of engine with supercharger includes air filter 1, booster 2, intercooler 3, air inlet pipe Road 4, air throttle 5, air inlet pressure sensor 6, inlet manifold 7, crankcase 8, gs-oil separator 9, high load capacity air pipeline 10, oil Gas separating device 11, underload air pipeline 12 and Pcv valve 13.Wherein, enter air inlet after cleaning filtering of the air by air filter 1 Pipeline 4 flows through booster 2 and is pressurized by compression, then flows through intercooler 3 and carry out cooling processing, pass through air throttle 5, air inlet pressure Force snesor 6 and inlet manifold 7, crankcase 8, eventually enter into cylinder.

In the course of work of internal combustion engine, the unburned gas in cylinder can be scurried by the gap between piston and cylinder jacket In crankcase 8, to prevent the gas leakage for scurrying into crankcase 8 from causing environmental pollution into atmosphere, crank case of internal combustion engine is divulged information System is designed to closed system, carries out Oil-gas Separation to unburned gas by gs-oil separator 9 (or gs-oil separator 11), then By high load capacity air pipeline 10 (or underload air pipeline 12), by treated, gas blowby is re-incorporated INTO in air inlet pipeline.

The assistance of external equipment is not needed, crankcase ventilation system is according to the spontaneous carry out high load capacity of the negative pressure condition in pipeline Switching between air pipeline 10 and underload air pipeline 12: negative after air filter 1 when engine operates in high load capacity operating condition Press larger, and without negative pressure after air throttle 5, crankcase ventilation is carried out by high load capacity pipeline 10 at this time, can will be in crankcase 8 Gas blowby is sucked in air inlet pipeline by high load capacity air pipeline 10；It is basic after air filter 1 when engine operates in running on the lower load Without negative pressure, and negative pressure is very big after air throttle 5, and crankcase ventilation is carried out by underload pipeline 12 at this time, can will be in crankcase 8 Gas blowby by underload air pipeline 12 suck air inlet pipeline in.

Wherein, the ventilation quantity when major function of Pcv valve 13 is control running on the lower load, in underload air pipeline 12.

Inventor is the study found that since high load capacity air pipeline 10 and underload air pipeline 12 are connect in gs-oil separator Between air inlet pipeline, structural stability is limited, along with the operating condition of engine influences, is easy to happen damaged or disconnects Failure pollutes environment so that crankcase gas blowby is leaked in atmosphere.

Therefore, it is necessary to strictly monitor the breakage of crankcase ventilation system air pipeline or disconnect failure, prevent because of ventilation Pipeline is damaged, disconnects and crankcase gas blowby is caused to be leaked in atmosphere.

For this purpose, inventor once attempted the diagnosis hand that the following two kinds crankcase ventilation system air pipeline disconnects, reveals failure Section:

(1), the real-time pressure of air pipeline is acquired by the pressure sensor being mounted in air pipeline, and is counted with simulation Pressure mould offset and threshold value under obtained normal condition are made comparisons, and judge that air pipeline has No leakage event according to pressure difference value Barrier；

(2), the theoretical air inflow of engine is acquired by being mounted on the intake flow sensor before air filter, and is increased with passing through The practical air inflow that the parameters such as pressure pressure, intake air temperature and engine speed are calculated is compared, according to the deviation of the two Judging air pipeline, whether there is or not leakage failures.

However, it is found by the inventors that still there are many problems in above two monitoring technology scheme: needing by pressure sensing Device or intake flow sensor diagnose higher cost；It needs largely to simulate and calculate, diagnosis algorithm and process are more complicated； Even if air pipeline leaks, the actual deviation of the pressure or air inflow that measure is smaller, so the discrimination of failure is not high, examines The sensitivity of disconnected method is lower.

Based on this, the embodiment of the present invention proposes a kind of pipeline diagnostic method, is not increasing pressure sensor or inlet air flow In the case where quantity sensor, electric lead is plated on air pipeline, realizes that air pipeline disconnects or breakage is let out using Circuit Connectivity The diagnosis for revealing failure forms one layer of electric lead that is, on air pipeline, detects being electrically connected for the electric lead using a detection circuit The general character recycles the electrical connectivity of the electric lead to judge the state of air pipeline: if the electric lead conducts, Damaging problem is not present in air pipeline region where electric lead；If what the electric lead was electrically off, where electric lead Air pipeline region occur damaged, cause corresponding electric lead to be broken.

Referring to fig. 2, the embodiment of the present invention pipeline diagnostic method comprising steps of

S1, diagnosis conducting wire is formed on the surface of pipeline to be diagnosed；

S2, the diagnosis conducting wire is accessed in a detection circuit；

S3, the status of electrically connecting that the diagnosis conducting wire is detected by the detection circuit；

S4, the state that pipeline to be diagnosed is judged according to the status of electrically connecting of the diagnosis conducting wire.

Specifically, in conjunction with Fig. 2, Fig. 3 and Fig. 4, the diagnostic method of the embodiment of the present invention is further described.

As shown in figure 3, to carry out the schematic diagram of deagnostic structure used in fault diagnosis to high load capacity air pipeline 10, to height Load air pipeline 10 first carries out step S1 before being diagnosed: forming diagnosis conducting wire on the surface of high load capacity air pipeline 10 14。

Optionally, diagnosis conducting wire 14 is formed on the surface of high load capacity air pipeline 10 using galvanoplastic.Certainly, negative in height Plating diagnosis conducting wire 14 can also be using other methods such as hot dips, only with respect to the side such as hot dip on the surface of lotus air pipeline 10 It is relatively thin to be formed by conducting wire using galvanoplastic for method, and thickness is uniform, at low cost, more agrees with of the invention " to diagnose conducting wire The anti-damaged leakage failure for pushing away air pipeline of electrical connectivity " diagnosis require.

Optionally, in conjunction with Fig. 4, diagnosing conducting wire 14 includes the first diagnosis conducting wire 141 and second opinion conducting wire 142, and first examines Disconnected conducting wire 141 and second opinion conducting wire 142 are separated from each other, are not connected directly.

Optionally, the both ends of the first diagnosis conducting wire 141 are distributed on the both ends of high load capacity air pipeline 10.As shown in figure 4, The first end point 141a of first diagnosis conducting wire is distributed in high load capacity air pipeline 10 close to one end of the second adapter cable plug 16, Second endpoint 141b of the first diagnosis conducting wire is distributed in high load capacity air pipeline 10 close to one end of the first adapter cable plug 15. Similarly, the both ends of second opinion conducting wire 142 are also just distributed on the both ends of high load capacity air pipeline 10: second opinion conducting wire First end point 142a is distributed in high load capacity air pipeline 10 close to one end of the second adapter cable plug 16, second opinion conducting wire Second endpoint 142b is distributed in high load capacity air pipeline 10 close to one end of the first adapter cable plug 15.

Optionally, as shown in figure 4, the first diagnosis conducting wire 141 and second opinion conducting wire 142 all uniformly and are jointly divided by S type It is distributed in the outer surface of entire high load capacity air pipeline 10.Certainly, the shape of the first diagnosis conducting wire 141 and second opinion conducting wire 142 It can also be the other shapes such as " W type " or " M type ", and the shape of the two can be identical, it can not also be identical.

Wherein, the first diagnosis conducting wire 141 and second opinion conducting wire 142 are distributed on the outer surface of high load capacity air pipeline 10 The closeer obtain the better, the outer surface for the full entire high load capacity air pipeline 10 that gathers as much as possible, so as to diagnose height to the maximum extent Subtle breakage failure on each region of load air pipeline 10, improves the accuracy and sensitivity of diagnosis.

In addition, the first diagnosis conducting wire 141 and second opinion conducting wire 142 can also be plated in entire high load capacity air pipeline 10 On inner surface or intermediate course, it can need to do flexible choice with electroplating technology so that visual examination is disconnected.

And then, it referring to Fig. 3 and Fig. 4, executes step S2: diagnosis conducting wire 14 is accessed in a detection circuit.The present invention is real It applies the electronic control unit (ECU) 18 that example takes engine included and makees detection circuit.

Referring to fig. 4, step S2 can be divided into following two step:

S21, second opinion conducting wire 142 is disconnected near the first end point 142a of second opinion conducting wire, in gap shape At two interfaces A and B；

S22, the electronic control unit 18 carried from gap access engine.

When executing step S22, as shown in figure 4, connecting wire 17 is drawn at interface A and B, that interface A is drawn One connecting wire 17a is connected with the pin 18a of electronic control unit 18, by interface B the second connecting wire 17b drawn and electronic control unit 18 pin 18b is connected.

Wherein, the power supply (mostly 5V power supply) and digital-to-analogue thief hatch (A/D thief hatch) of pin 18a and electronic control unit 18 It is connected, pin 18b is connected with the ground line (GND) of electronic control unit 18.

At this point, because the first diagnosis conducting wire 141 is electrically connected not yet with second opinion conducting wire 142, the first diagnosis conducting wire 141, there are no form galvanic circle between second opinion conducting wire 142 and electronic control unit 18.

As shown in Figure 1, it is contemplated that the disconnected high load capacity air pipeline 10 of follow-up be connect gs-oil separator 9 and air inlet pipeline it Between, in addition to the leakage because caused by occurring breakage for high load capacity air pipeline 10, there is also one because of high load capacity air pipeline 10 End and gs-oil separator 9 or air inlet pipeline disconnect caused by leakage.

Therefore, diagnostic method of the invention can also relate to high load capacity air pipeline 10 and gs-oil separator 9 or air inlet The pipe interface state-detection of pipeline.

Based on this, as shown in figure 4, in being provided at the pipe interface of high load capacity air pipeline 10 and gs-oil separator 9 The first empty switching conductive plug 15 is provided with hollow the at the pipe interface of high load capacity air pipeline 10 and air inlet pipeline Two switching conductive plugs 16.

To form complete galvanic circle and crankcase ventilation system, high load capacity air pipeline 10 is also passed through first turn It connects conductive plug 15 and the second switching conductive plug 16 accesses in crankcase ventilation system, as shown in figure 3, high load capacity air pipeline 10 one end is connected to by the first switching conductive plug 15 with gs-oil separator 9, and the other end of high load capacity air pipeline 10 passes through Second switching conductive plug 16 is connected to air inlet pipeline.

In addition, the inner surface of the inner surface of the first switching conductive plug 15 and the second switching conductive plug 16 is conductivity meter Face has conducting function, such as can be and formed by the metal material to conduct electricity very well.

When one end of high load capacity air pipeline 10 is connected with the first switching conductive plug 15, the second of the first diagnosis conducting wire Second endpoint 142b of endpoint 141b and second opinion conducting wire is contacted with the metallic interior surface of the first switching conductive plug 15 respectively, To realize the conducting between the first diagnosis conducting wire 141 and second opinion conducting wire 142.Likewise, in high load capacity air pipeline 10 The other end on, first diagnosis conducting wire 141 and second opinion conducting wire 142 between be connected.

At this point, the first diagnosis conducting wire 141 and second opinion conducting wire 142 pass through the first switching conductive plug 15 and the second switching Conductive plug 16 constitutes electrical connection, and forms a complete galvanic circle, the circuit with the power supply in electronic control unit 18 Equivalent circuit diagram it is as shown in Figure 5.In figure, R₁Indicate the internal resistance of power supply, R₂Indicate that the first diagnosis conducting wire 141 and second is examined The series equivalent resistance of disconnected conducting wire 142, the first switching conductive plug 15, second switching conductive plug 16, the first connecting wire 17a And second the connecting wires such as connecting wire 17b resistance very little, can be neglected.

As shown in figure 5, the 5V in entire galvanic circle, inside the pin 18a access electronic control unit 18 of electronic control unit 18 Power supply and A/D thief hatch；Pin 18b is grounded by electronic control unit 18.After being powered by storage battery to electronic control unit 18, A/D thief hatch can at real-time collection and continual collection 18a, i.e. the voltage-to-ground value of interface A.

For circuit as shown in Figure 5, there are following several situations:

(1), when high load capacity air pipeline 10 connects intact, entire circuit loop conducting, the collected electricity of A/D thief hatch Pressure value are as follows:

(2), it is sent out when between high load capacity air pipeline 10 and the first switching conductive plug 15 or the second switching conductive plug 16 When raw disconnection failure, resistance R₂Inside disconnects, between the first diagnosis conducting wire 141, second opinion conducting wire 142 and electronic control unit 18 Galvanic circle is destroyed, and the voltage value of the collected interface A of A/D thief hatch is 5V；

(3), when breakage occurs for high load capacity air pipeline 10, as long as the diameter of damaged crackle is greater than the first diagnosis conducting wire Spacing between the internal each adjacent lead segments of 141 (or 142 conducting wires of second opinion conducting wire) is (between adjacent lead segments Away from can require determine according to diagnosis), then will lead to certain diagnosis conducting wire on 10 surface of high load capacity air pipeline, (first diagnoses and leads Line 141 or second opinion conducting wire 142) it disconnects, so as to cause resistance R₂Inside disconnects, the interface A that A/D thief hatch is read at this time Voltage value be also 5V.

Therefore, high load capacity air pipeline 10 can be determined according to (over the ground) voltage value for the interface A that A/D thief hatch is read Whether break down: if the voltage value of interface A is equal to the voltage 5V of power supply, galvanic circle is disconnected, high load capacity ventilation duct Road 10 occurs damaged or disconnects failure；If the voltage value of interface A is less than the voltage 5V of power supply, galvanic circle conducting is high 10 normally of load air pipeline.

Wherein, because the internal resistance effect of the sudden strain of a muscle difference and power supply of power supply, other conducting wires, high load capacity air pipeline 10 are sent out When raw damaged or disconnection failure, the voltage value of the collected interface A of A/D thief hatch is not that just should be slightly less than power supply electricity for 5V The voltage in source, depending on specific circuit structure.

Optionally, circuit structure is designed, when damaged or disconnection failure occurs for high load capacity air pipeline 10, so that A/D is adopted The voltage value of the collected interface A of sample mouth is stablized near 5V, and the voltage value that selection supply voltage floats downward 0%-10%, which is used as, to be sentenced Definite value such as chooses the section 4.5V-5V voltage value as judgment basis, and judges whether to break down accordingly: if interface A's is real-time Voltage-to-ground value is located in the range of 4.5V-5V, then the galvanic circle disconnects；If the real-time voltage-to-ground value of interface A is less than 4.5V, then the galvanic circle conducting.

In addition it is also possible to the voltage value by comparing the interface A acquired in real time and interface A when the normally of galvanic circle Voltage valueSize judge the on-off of galvanic circle, and then determine whether leakage failure.

Step S3 is executed referring to Fig. 6 based on this, that is, passes through the first diagnosis conducting wire 141 of detection circuit detection and second opinion The electrical communication state of conducting wire 142:

S31, determine whether electronic control unit 18 works normally by the voltage for storage battery of powering, if so then execute step S32；

The voltage value of S32, real-time acquisition interface A, and compare collection value withSize, if in real time collection value it is big InThe then separated electrical connection of the first diagnosis conducting wire 141 and second opinion conducting wire 142.

In step S31, if the voltage of power supply storage battery is unsatisfactory for requiring, i.e. 18 cisco unity malfunction of electronic control unit is then weighed Multiple step S31 is until the voltage of power supply storage battery meets diagnostic work requirement, enters step S32.

Theory when in step s 32, by comparing the real-time collection voltages value and galvanic circle normally at interface A Voltage valueSize judge the on off operating mode of galvanic circle: if collection voltages value is greater than theoretical voltage value and (connects in real time The voltage 5V of nearly power supply), then galvanic circle disconnects, i.e., the inside of the first diagnosis conducting wire 141 or second opinion conducting wire 142 is disconnected It opens, also or high load capacity air pipeline 10 is between interface and the first switching conductive plug 15 or the second switching conductive plug 16 It disconnects；If if collection voltages value is equal to theoretical voltage value, galvanic circle conducting in real time.

Wherein, the size of theoretical voltage value can be by R₁And R₂Measured value derivation calculate, can also be directly by normally leading It measures logical galvanic circle.

Similarly, it is contemplated that the internal resistance effect of the sudden strain of a muscle difference and power supply, other conducting wires of power supply, high load capacity air pipeline 10 When normally, the voltage value of the collected interface A of A/D thief hatch is not just to beThe theoretical value should be slightly less than, depending on Depending on specific circuit structure.

Optionally, circuit structure is designed, when high load capacity 10 normally of air pipeline, so that A/D thief hatch collects Interface A voltage value stablize existNear, using the value of theoretical value floating 5%-10% as decision content, and accordingly Judge whether to break down: if the real-time voltage-to-ground value of interface A is greater than the decision content, the galvanic circle is disconnected；If The real-time voltage-to-ground value of interface A is less than or equal to the decision content, then the galvanic circle conducting.

In addition, can also be advanced optimized to step S32, voltage (5V) and the galvanic circle to the power supply The voltage-to-ground value of on state lower interface ABe averaging, in the hope of average value be the galvanic circle on-off Judgment basis, and judge the on off operating mode of the galvanic circle accordingly:

If the real-time voltage-to-ground value of interface A is more than or equal to the average value, the galvanic circle is disconnected；

If the real-time voltage-to-ground value of interface A is less than the average value, the galvanic circle conducting.

And then, referring to Fig. 6, step S4 is executed, high load capacity ventilation duct is judged according to the on off operating mode of the galvanic circle The state on road 10: if galvanic circle disconnects, high load capacity air pipeline 10 occurs damaged or disconnects failure；If galvanic circle is led Logical, then leakage failure, normally is not present in high load capacity air pipeline 10.

Similarly, above-mentioned diagnostic method can also be used for the malfunction monitoring of underload air pipeline 12, diagnosis.

In addition, above-described embodiment is only for using engine electric-controlled unit (ECU) as an implementation of detection circuit Example, in addition to this it is possible to utilize the detection circuit of other forms；And diagnosis conducting wire wait diagnose the distributing position on pipeline, Distribution shape, the distribution parameters such as spacing and item number can do corresponding adjustment, and this will not be repeated here.

In conclusion being utilized in engine crankshaft ventilation system pipeline diagnostic method provided in an embodiment of the present invention Circuit communication sex determination, the breakage for diagnosing air pipeline disconnect failure, and decision process and algorithm are simple, while the spirit diagnosed Sensitivity is high, it is easy to can find damaged or disconnect failure；In addition, the electronic control unit building detection electricity carried using engine Road does not need additional device or device, has simplified deagnostic structure, reduces fault diagnosis, the monitoring cost of air pipeline.

It should be noted that, in this document, the relational terms of such as " first " and " second " or the like are used merely to one A entity is distinguished with another entity, and without necessarily requiring or implying between these entities, there are any this actual Relationship or sequence.

The above is only a preferred embodiment of the present invention, does not play the role of any restrictions to the present invention.Belonging to any Those skilled in the art, in the range of not departing from technical solution of the present invention, to the invention discloses technical solution and Technology contents make the variation such as any type of equivalent replacement or modification, belong to the content without departing from technical solution of the present invention, still Within belonging to the scope of protection of the present invention.