DE112017007362T5 - Single-cylinder engine misfire detection device, method and vehicle - Google Patents

Abstract

An accurate misfire decision in a single-cylinder engine is made possible without measuring an inter-tooth error of a crankshaft pulse rotor.
A crankshaft angular velocity measuring unit (5b) measures an angular velocity at each crankshaft angle. A 720 degree filter processing unit (6b) removes load change and friction change components. A relative speed calculation unit (7b) calculates a relative speed at each crankshaft angle with respect to a reference angular velocity, which is detected in each of the vicinity of the compression top dead center and the vicinity of the engine top dead center. An integration angular velocity calculation unit (8b) integrates the relative angular velocity within a predetermined crank angle range to calculate an integration angular velocity for each of an expansion stroke and an intake stroke. A misfire parameter calculation unit (10b) calculates a misfire parameter from the integration angular velocity, the reference angular velocity and a pumping torque component, which is set in advance on a control unit. A misfire decision unit (11b) decides on the basis of the misfire parameter whether there is a misfire or not.

Description

Technical area

The present invention relates to a single-cylinder engine misfire detection device and method and a single-cylinder engine vehicle, and more particularly, to a single-cylinder engine misfire detection device and method and a single-cylinder engine vehicle that performs misfire detection with high accuracy without measuring an inter-tooth error of a crankshaft pulse rotor for each vehicle using a single-cylinder engine characteristic , can execute.

background

In a four-wheel vehicle, a technology is known which determines a misfire of an engine on the basis of a crankshaft angular velocity, measured from the time intervals of the crankshaft pulse generation (crankshaft pulse time intervals). Since a misfire decision flag includes an angular velocity component that results from an inter-tooth error of a crankshaft pulse rotor in order to make an accurate misfire decision, it is necessary to eliminate an inter-tooth error.

PTL 1 discloses a technology that calculates a relative angular velocity of each crankshaft angle with respect to a reference angular velocity that is detected near the top compression dead center of an engine based on a crankshaft speed, and uses an integrated value of such relative angular velocities as a misfire parameter.

PTL 2 discloses a technology that calculates a difference in the crankshaft angular velocity change value for each cylinder of the single-cylinder engine and uses the value of the difference as a misfire parameter such that an angular velocity component resulting from an inter-tooth error of a crankshaft pulse rotor is removed from the misfire parameter.

List of publications

patent literature

• [PTL 1] Japanese Patent Laid-Open No. 2008-111354
• [PTL 2] Japanese Patent Laid-Open No. 2014-199040

Summary

Technical problem

In recent years, with a view to improving the repairability and environmental protection, even in a motorcycle (motorcycle), the introduction of a misfire technology is being investigated. In a motorcycle, the requirement of diversity for a performance or characteristic of an engine, an explosion engine of uneven intervals, or a single-cylinder engine is adopted.

Since the method for eliminating inter-tooth faults for a crankshaft pulse rotor in PTL 1 is a technology utilizing a characteristic of an uneven-control type explosion engine, it can not be applied to a single-cylinder engine. The misfire detection technique of PTL 2 can not remove an angular velocity component resulting from the pumping torque, the load torque generated within a cycle, and a friction change.

The object of the present invention is to provide a single-cylinder engine misfire detection device and method and a single-cylinder motor vehicle that remove an angular velocity component resulting from an inter-tooth error of a crankshaft pulse rotor from a misfire parameter without measuring an inter-tooth error of the crankshaft pulse rotor in the single-cylinder engine, so that misfire detection can be performed with high accuracy.

Means for problem solving

To achieve the above object, the feature of the present invention in a misfire detection device for a single cylinder engine is to have the following features.

(1) A misfire detection device for a single cylinder engine of the present invention comprises means ( 4a . 4b ) for determining an angular velocity at each crankshaft angle from an inter-crankshaft pulse time period, mean ( 7b ) for computing a relative angular velocity at each crankshaft angle with respect to a reference angular velocity detected in the vicinity of an upper compression dead center and the vicinity of an upper exhaust dead center of the engine based on the angular velocity at each crankshaft angle. 8b ) to integrate the relative angular velocity within a given crankshaft angle range to calculate a Integration angular velocity for each includes an expansion stroke and an intake stroke; and misfire parameter calculation means ( 10b ), for calculating an integration angular velocity, which results from the combustion torque of the integration angular velocity, the reference angular velocity and a specially detected pumping torque component, and for determining the calculated integration angular velocity as a misfire parameter.

(2) A misfire detection method for a single cylinder engine of the present invention includes determining an angular velocity at each crankshaft angle from an inter-crankshaft pulse time period, calculating a relative angular velocity at each crankshaft angle with respect to a reference angular velocity that is in the vicinity of an upper compression dead center and the vicinity of an upper exhaust dead center of the engine based on the angular velocity at each crankshaft angle, integrating the relative angular velocity within a given crankshaft angular range to calculate an integration angular velocity for each expansion stroke and each intake stroke; and calculating an integration angular velocity resulting from the combustion torque, the integration angular velocity, the reference angular velocity and a specially detected pumping torque component, and to determine the calculated integration angular velocity as a misfire parameter.

(3) A vehicle incorporating a single-cylinder engine of the present invention includes means for detecting an angular velocity at each crank angle from an intermediate crankshaft pulse period, means for calculating a relative angular velocity at each crank angle with respect to a reference angular velocity in each vicinity of an upper one Compression deadpoint and near an engine exhaust top dead center is detected based on the angular velocity at each crankshaft angle; means for integrating the relative angular velocity within a given crankshaft angle range to calculate an integration angular velocity for each expansion stroke and each intake stroke; and the misfire parameter calculating means for calculating an integration angular velocity resulting from the combustion torque of the integration angular velocity, the reference angular velocity and a specially detected pumping torque component, and determining the calculated integration angular velocity as the misfiring parameter.

(4) The misfire parameter calculating means for removing an integration angular velocity component resulting from the pumping torque of the integration angular velocity in an expansion stroke to calculate a first integration angular velocity after removal, means for removing an integration angular velocity component resulting from the pumping torque of the integration angular velocity in an intake stroke is formed to calculate a second integration angular velocity after removal; and means for subtracting the second angular integration velocity after the distance corrected with a ratio between the reference angular velocities in the expansion stroke and the intake stroke to determine a misfire parameter from the first angular integration velocity after the removal.

(5) The misfire detection device for a single cylinder engine further comprises means ( 6b ) removing a first angular rate fluctuation component that may occur in a vehicle-carried engine from a result of detecting the angular rate, the means for calculating a relative angular rate calculating a relative angular rate aimed at an angular rate from which the first angular rate fluctuating component is removed.

(6) The first angular velocity fluctuation component is an angular velocity fluctuation component resulting from the load torque of a tire or an accessory of an engine driven vehicle and the friction of a sliding part of the engine.

Advantageous Effects of the Invention

(1) According to the misfire detection device, misfire detection method, and vehicle of the present invention, since it becomes possible to remove an inter-tooth error component from a misfire parameter without measuring the inter-tooth error of the crankshaft pulse rotor, the misfire decision can be achieved by utilizing the fact That is, in a single-cylinder engine, explosions occur only once during one cycle and the angular velocity at each crank angle in an expansion stroke in which combustion torque is generated and an intake stroke in which combustion torque is not generated are measured at a same portion of a crankshaft pulse rotor ,

(2) Since misfire parameter calculation means is the Integral angular velocity component resulting from the pumping torque of the integrational angular velocity in the expansion stroke, to determine a first post-angular integration angular velocity, remove the integration angular velocity component resulting from the pumping torque of the integration angular velocity in the inlet stroke by a second integration angular velocity after removal and to subtract the second post-removal angular integration angular velocity, which is corrected with the ratio between the reference angular velocities in the expansion stroke and the intake stroke from the first post-removal angular integration velocity, to determine a misfire parameter, it becomes possible to determine the mating flank component from the misfire parameter regardless of the angular velocity difference between the expansion stroke and the intake stroke.

(3) Since the misfire detecting apparatus for a single-cylinder engine includes means for removing a first angular velocity fluctuation component possibly occurring in a vehicle-mounted engine from the result of the angular velocity detection and relative angular velocity calculating means includes a relative angular velocity aimed at the angular velocity, From which the first angular velocity fluctuation component is removed, it is possible to eliminate the influence of the first angular velocity fluctuation components.

(4) Since an angular velocity fluctuation component resulting from the load torque of a tire or an accessory of the motor vehicle and the friction of a sliding part of the engine is removed as the first angular velocity fluctuation component, a misfire decision with high accuracy becomes possible.

list of figures

• 1 FIG. 12 is a block diagram illustrating a method and an apparatus for detecting misfiring of a single-cylinder engine and a single-cylinder engine to which the present invention is applied.
• 2 represents a change in the angular velocity when the continuous operation is performed in the fuel cut state of the engine frame.
• 3 represents a function of a 720 degree filter.
• 4 represents a function of a relative angular velocity calculation unit.
• 5 represents a function of an integration angular velocity calculation unit.
• 6 is an example of the calculation result of a moment of inertia determined by the desktop calculation.
• 7 represents a function of an extraction unit for an inertial torque component.
• 8th represents an example of a pumping torque component when the throttle valve value is fully closed.
• 9 FIG. 10 illustrates a misfire detection method in which a relative angular velocity is determined from an angular velocity detected every crankshaft pulse generation and an integrated value of the relative angular velocity is determined as a misfire parameter (no misfire).
• 10 represents a misfire detection method in which a relative angular velocity is determined from an angular velocity detected each time a crankshaft pulse is generated and an integrated value of the relative angular velocity is determined as a misfire parameter (misfire).

Description of the embodiment

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. First, an outline of a misfire detection method based on a crankshaft angular velocity and the present invention will be given herein, and then an embodiment of the present invention will be described in detail.

9 and 10 FIG. 11 is views illustrating an example of a misfire detection method in which a relative angular velocity is determined in a two-cylinder engine, from an angular velocity detected every crankshaft pulse generation, and an integrated value of the relative angular velocity (integrated angular velocity) is determined as a misfire parameter. The relative angular velocity is calculated by subtracting a reference angular velocity detected near the compression top dead center of each cylinder of an engine from an angular velocity detected each time a crankshaft pulse is generated.

Reference marks # 1 and # 2 in 9 and 10 denote cylinder designations for identifying two cylinders according to a firing order. 9 represents a case in which the Combustion in all cylinders of # 1 and # 2 runs normally. 10 represents a case where misfire occurs only in # 1 cylinder.

As the relative angular velocity increases as the combustion is normally performed in a combustion stroke after the compression top dead center, the relative angular velocity decreases when a misfire occurs. The integration angular velocity obtained by integrating the relative angular velocity within a predetermined crank angle range indicates a positive value in the cylinder in which the combustion is normally performed, but indicates a negative value in the cylinder in which a misfire occurs. Accordingly, the integration angular velocity can be used as a parameter for deciding a misfire cylinder.

However, the integration angular velocity contains a fluctuating angular velocity component which, in addition to the combustion torque, results from an inter-tooth error of a crankshaft pulse rotor, noise, load torque, friction, inertia torque, pumping torque etc. caused by a dynamic change in a sensor gap. In order to be able to carry out an accurate misfire detection, it is therefore necessary to remove all fluctuation components from the integration angular velocity.

With regard to noise, load moments, frictional and inertial moments from the fluctuation components described above, a technique is known which removes them by means of statistical processing, motor control, desktop calculation or the like. However, no effective removal method has been established with regard to the pumping torque.

The pumping torque is a torque generated by the pumping motion of a piston in intake, compression, expansion and exhaust strokes of an engine. Accordingly, the pumping torque is a parameter different from a pumping loss representing an energy loss occurring in the intake stroke and the exhaust stroke of the engine.

In the present invention, for each vehicle model that performs misfire detection, an environment is prepared in which a standard vehicle Mref having an ideal crankshaft pulse rotor in which a gear error between the gears is substantially zero is prepared in advance to acquire an inter-tooth error component eliminate. Subsequently, fluctuation components other than the pumping torque are removed by the above-described suitable technique using the standard vehicle Mref to determine and extract an integration angular velocity at which the pumping torque component is dominant as the pumping torque component unique to the vehicle model, and then become the determined one pumping torque component is set as data to an electronic control unit (ECU) of each mass-produced vehicle. Thus, the pumping torque component may be removed from a misfire parameter.

Since only one explosion occurs during a cycle in a single-cylinder engine, the angular velocity at each crankshaft angle in the expansion stroke in which the combustion torque is generated and the intake stroke in which the combustion torque is not generated can be measured on the same section of the crankshaft pulse rotor.

An inter-tooth error component and an inertia torque component are in the integrating angular velocity (first integrating angular velocity) with respect to one in the vicinity of the upper compression dead point, which is a starting point of an expansion stroke, and another integration angular velocity (second integration angular velocity) with respect to one in the vicinity of the upper exhaust dead point, which is a starting point of an intake stroke, includes detected reference angular velocity. However, the inter-tooth error components and the moment of inertia components are proportional to the angular velocity. Thus, when an angular velocity difference between the strokes is corrected, the inter-tooth error components and moment of inertia components included in the first integration angular velocity and the second integration angular velocity are set equal.

If the difference between the first integration angular velocity and the second integration angular velocity, whose angular velocity difference between the strokes is corrected, is determined as a misfire parameter, the intermediate tooth error components and the moment of inertia components after the angular velocity correction in the first and second integration angular velocity are the same, and the intermediate tooth error components and the moment of inertia components become off removed the misfire parameter. The angular rate variation component resulting from the noise, load torque, friction, and pumping torque included in the misfire parameter can be removed using the appropriate technique described above. For this reason, in a single cylinder engine a misfire decision with high accuracy is possible without an inter-tooth error measurement of a crankshaft pulse being carried out for each vehicle.

The embodiment of the present invention will now be described in detail with reference to the drawings. 1 FIG. 12 is a block diagram illustrating a method and apparatus for misfire detection on a single-cylinder engine and a single-cylinder engine vehicle to which the present invention is applied.

A standard vehicle Mref includes a single-cylinder engine E equipped with an ideal crankshaft pulse rotor 3ref mounted on a crankshaft 2 of the single-cylinder engine E and has a substantially zero inter-tooth error between the gears, and has an extraction device 100 for the component extraction of the pumping torque.

In the extraction device 100 for the pumping torque component measures a crankshaft angular velocity measuring unit 5a the angular velocity in a state where the combustion torque is not generated substantially. Therefore, the interpulse period of the ideal crankshaft pulse rotor 3ref becomes the fuel cut off state of a crankshaft pulse sensor 4a measured to calculate an angular velocity at each crankshaft angle. A known sliding averaging process or the like is applied to the angular velocity at each crank angle to remove noise components. 2 represents a change in the angular velocity when the stationary operation is performed in a fuel-cut state in the engine frame.

A 720 degree filter processing unit 6a picks up a linear change within a cycle period aimed at a result of calculating an angular velocity ω, and extracts a fluctuation component whose cycle is comparatively short. Consequently, an angular velocity fluctuation component resulting from the load torque applied by a tire or an accessory of the engine-driven vehicle or the friction of a sliding part of the engine can be removed.

3 illustrates an example in which a 720 degree filter is applied to a cycle within which the velocity is reduced by load torque, although combustion momentum is generated. Since the extraction of a pumping torque component in stationary operation takes place in the machine frame, the linear change of the angular velocity within a cycle is very small.

Since vibration components are removed by the above-described filtering process in a state where the combustion torque is substantially zero, essentially only vibration components by inertia moment and pumping torque are taken into account in the obtained angular velocity ω.

A relative speed calculation unit 7a calculated by using the angular velocity ω (crankshaft angle 0 degrees) measured near the compression top dead center as the reference angular velocity ωlref, as shown in FIG 4 1, the difference between an angular velocity ω1_i measured at each crank angle i within a crank angle range of 180 degrees from the compression top dead center and the reference angular velocity colref as a first relative angular velocity ωω1_i (= ω1_i-colref).

Likewise, using the angular velocity ω (crankshaft angle 360 degrees) measured near the top exhaust dead center as the reference angular velocity ω2ref, the difference between an angular velocity ω2_j measured in each crankshaft angle j within each crankshaft angle range of 180 degrees from the top exhaust dead center and the reference angular velocity ω2ref as a second relative Angular velocity ωω2_j (= ω2_j - ω2ref) calculated.

As in 5 shown, integrates an integration angle calculation unit 8a the first and second relative angular velocities ωω1_i and ω2_j to calculate a first integration angular velocity Σωω1_i and a second integration angular velocity Σωω2_j, respectively.

An inertial torque component removal unit 9a removes inertial torque components determined by desktop computation from the first and second integration angular velocities Σωω1_i and Σωω2_j to calculate a first integration angular velocity Σωω1'_i after removal and a second integration angular velocity Σωω2'_j after removal.

The inertia torque Tq for a single cylinder may be determined based on a connecting rod length L, a crankshaft radius R, an offset e, an angular velocity ω of the crankshaft, a total mass m of the piston and the connecting rod, for example, as indicated in PTL 2, and for example, like in 6 represented, determined.

The moment of inertia Tq can be approximated by representing the inertial mass of the piston, connecting rod, crankshaft, etc. as I by an equation of motion of the rotation of the following expression. $$\text{Tq}=\text{I}\times \left(\text{d}\mathrm{\omega }\text{/ dt}\right)$$

What is to be determined in the present embodiment is an angular velocity change dω by moment of inertia Tq and is determined by converting the above expression ( 1 ) in the following expression (2). $$\text{T}\mathrm{\omega }=\text{Tq}\times \left(\text{dt / I}\right)$$

In particular, the angular velocity change amount dω can be determined by moment of inertia using the moment of inertia Tq generated at a certain motor speed, the inertial mass I and the required time period dt required for the rotation by a unit angle at the certain motor speed, and will be, for example, as in FIG 7 shown. Accordingly, it can be seen that in the event that the reference angular velocities in the expansion stroke and in the inlet stroke are the same, the relative angular velocities with respect to the upper compression dead center and the upper outlet dead center are the same.

In the present embodiment, since a value obtained by integrating a relative angular velocity with respect to the top compression dead center is required, it is sufficient if an integrated value of a relative value dω 'with respect to a value of the top compression dead center of the angular velocity change dω by Moment of inertia is determined. With respect to the angular velocity change amount dω 'described above, it is necessary to perform a process corresponding to that of the noise suppression technique applied to the angular velocity at each crankshaft angle. The moment of inertia component at each engine speed can be determined by determining an integration value of the angular rate change amount dω 'in a unit speed and data to the extractor 100 of the pumping torque and this value is then multiplied by the reference angular velocity.

In the present embodiment, if the first and second integration angular velocities Σωω1'_i and Σωω2'_j are determined after removal as described above, they are extracted as a pumping torque component in the expansion stroke and as a pumping torque component in the intake stroke. 7 shows an example in which an initial torque component ( 2 ) from an integration value ( 1 ) the relative angular velocity is removed to create a pumping torque component ( 3 ) extract.

The pumping torque component depends on the engine speed and throttle opening, and the fully closed throttle pump torque component is, for example, as in FIG 8th shown. The extraction of the pumping torque component is determined in the form of a map, for example, by the engine speed and the intake manifold pressure using the engine speed as a parameter.

Since the specific pumping torque component as described above is common to vehicles of the same model, the pumping torque component is set as data to the ECU of large-series vehicles M whose model is the same and used to correct a misfire parameter.

With reference to 1 each large-series vehicle M includes a misfire decision device 300 and calculates an on-going misfire parameter to decide whether or not there is a misfire. In the misfire decision device 300 determines a crankshaft angular velocity measuring unit 5b an angular velocity ω.

A 720 degree filter processing unit 6b removes an angular velocity fluctuation component resulting from load torque and friction. A relative angular velocity calculation unit 7b calculates first and second relative angular velocities ωω1_i and ωω2_j. An integration angular velocity calculation unit 8b calculates the first and second integration angular velocities Σωω1_i and Σωω2_j.

A misfire parameter calculation unit 10b calculates a misfire parameter using the first and second integration angular velocities, the pumping torque component data set to the ECU using the standard vehicle Mref, and the first and second reference angular velocities ω1ref and ω2ref.

$${\displaystyle \sum \mathrm{\omega \omega }2\_\text{j}}=\text{P2}+\text{I2}+\text{H2}$$

The integration angular velocity Σωω1_i in the expansion stroke (first integration angular velocity) and the integration angular velocity Σωω2_j in the inlet stroke (second integration angular velocity) can be determined by the expressions given below ( 3 ) and (4) if the Combustion torque component is represented by N; the pumping torque components in the expansion stroke and the suction stroke are represented by P1 (first pumping torque component) and P2 (second pumping torque component); the moment of inertia components in the expansion stroke and the suction stroke are represented by 11 and 12; and the components are represented by the tooth errors in the expansion stroke and in the suction stroke by H1 and H2.
$${\displaystyle <figure-callout\; id="1"\; label="\Sigma \; \omega \omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\Sigma \; </figure-callout>\mathrm{\omega \omega }\mathrm{}1\_\text{i}}=\text{N}+\text{P1}+\text{I1}+\text{I1}+\text{H1}$$

$${\displaystyle <figure-callout\; id="2"\; label="\Sigma \; \omega \omega "\; filenames="DE112017007362T5\_0012.png,DE112017007362T5\_0017.png"\; state="\{\{state\}\}">\Sigma \; </figure-callout>\mathrm{\omega \omega }\mathrm{}2\_\text{j}}=\text{P2}+\text{I2}+\text{H2}$$

$$\text{I2}=\mathrm{\omega 2}\text{ref}\times \text{I}\mathrm{0,}\text{ H2}=\mathrm{\omega 2}\text{ref}\times \text{H}0$$

Since the moment of inertia component I and the inter-tooth error H are related to the engine speed, when the moment of inertia component and the inter-tooth component at a unit speed are represented by 10 and H0, respectively, the moment of inertia components 11 and 12 are represented by the following expressions (5) and (6), respectively.
$$\text{I2}=\mathrm{<figure-callout\; id="1"\; label="\omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\omega </figure-callout>}1\text{ref}\times \text{I}0\text{H1}=\mathrm{<figure-callout\; id="1"\; label="\omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\omega </figure-callout>}1\text{ref}\times \text{<figure-callout id="0" label="H" filenames="DE112017007362T5\_0013.png,DE112017007362T5\_0014.png" state="{{state}}">H</figure-callout>}0$$

$$\text{I2}=\mathrm{\omega 2}\text{ref}\times \text{I}0\text{H2}=\mathrm{\omega 2}\text{ref}\times \text{<figure-callout id="0" label="H" filenames="DE112017007362T5\_0013.png,DE112017007362T5\_0014.png" state="{{state}}">H</figure-callout>}0$$

$$\text{N}=\left({\displaystyle \sum \mathrm{\omega \omega }1\_\text{i}}-\text{P}1\right)\mathrm{-\omega }1\text{ref}\times \left(\text{I0}+\text{H0}\right)$$

$${\displaystyle \sum \mathrm{\omega \omega }2\_\text{j}}=\text{P2}+\text{I2}+\text{H2}=\text{P2}+\mathrm{\omega }2\text{ref}\times \left(\text{I0}+\text{H0}\right)$$

$$\text{I}0+\text{H}0=1\text{/}\times \left({\displaystyle \sum \mathrm{\omega \omega }2\text{\_j}-\text{P}2}\right)$$

The following expression (7) is derived from the above expressions (3) and (5), and the following expression (8) is derived from the expressions (4) and (6).
$${\displaystyle <figure-callout\; id="1"\; label="\Sigma \; \omega \omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\Sigma \; </figure-callout>\mathrm{\omega \omega }\mathrm{}1\_\text{i}}=\text{N}+\text{P1}+\text{I1}+\text{H1}=\text{N}+\text{P1}+\mathrm{<figure-callout\; id="1"\; label="\omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\omega </figure-callout>}1\text{ref}\times \left(\text{I0}+\text{H0}\right)$$

$$\text{N}=\left({\displaystyle \Sigma \mathrm{\omega \omega }1\_\text{i}}-\text{P}1\right)\mathrm{-<figure-callout\; id="1"\; label="\omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\omega </figure-callout>}1\text{ref}\times \left(\text{I0}+\text{H0}\right)$$

$${\displaystyle <figure-callout\; id="2"\; label="\Sigma \; \omega \omega "\; filenames="DE112017007362T5\_0012.png,DE112017007362T5\_0017.png"\; state="\{\{state\}\}">\Sigma \; </figure-callout>\mathrm{\omega \omega }\mathrm{}2\_\text{j}}=\text{P2}+\text{I2}+\text{H2}=\text{P2}+\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="DE112017007362T5\_0012.png,DE112017007362T5\_0017.png"\; state="\{\{state\}\}">\omega </figure-callout>}2\text{ref}\times \left(\text{I0}+\text{H0}\right)$$

$$\text{I}0+\text{<figure-callout id="0" label="H" filenames="DE112017007362T5\_0013.png,DE112017007362T5\_0014.png" state="{{state}}">H</figure-callout>}0=1\text{/}\times \left({\displaystyle \Sigma \mathrm{\omega \omega }2\text{\_j}-\text{P}2}\right)$$

From the expressions (7) and (8), the integration angular velocity component is determined by the combustion torque in the manner given by the following expression (9).

$$\begin{array}{l}\text{N}={\displaystyle <figure-callout\; id="1"\; label="\Sigma \; \omega \omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\Sigma \; </figure-callout>\mathrm{\omega \omega }\mathrm{}1\_\text{i}-\text{P}1-\left(\text{I}1+\text{H}1\right)}\\ =\left({\displaystyle \Sigma \mathrm{<figure-callout\; id="1"\; label="\omega \omega "\; filenames="DE112017007362T5\_0017.png,DE112017007362T5\_0019.png"\; state="\{\{state\}\}">\omega \omega </figure-callout>}1\_\text{i}-\text{P}1}\right)-\mathrm{\omega }\text{1ref /}\mathrm{\omega 2}\text{ref}\times \left({\displaystyle \Sigma \mathrm{\omega \omega }\text{2}\_\text{i}-\text{P2}}\right)\end{array}$$

In particular, the first pumping torque component becomes P1 removed from the first integration angular velocity to determine a first integration angular velocity after removal and the second pumping torque component P2 is removed from the second integration angular velocity to determine a second integration angular velocity after removal. In order to correct the angular velocity difference between the strokes, the second integration angular velocity after removal is multiplied, the ratio ω1ref / ω2ref between the reference angular velocities, and the value N of the above expression (Fig. 9 ) obtained by subtracting the product from the first integration angular velocity is used as the misfire parameter. A misfire decision section 11b decides whether or not there is a misfire due to the misfire parameter.

According to the present embodiment, in the single-cylinder engine, an inter-tooth error can be removed from a misfire parameter without measuring an inter-tooth error of the crankshaft pulse rotor in the standard vehicle, so that a misfire decision can be achieved with high accuracy.

LIST OF REFERENCE NUMBERS

2 ... crankshaft, 3 ... crankshaft pulse rotor, 3ref ... ideal crankshaft pulse rotor, 4a, 4b ... crankshaft pulse sensor, 5a, 5b ... crankshaft angular velocity measuring unit, 6a, 6b ... 720-degree filter processing unit, 7a, 7b ... relative angular velocity calculation unit, 8a, 8b ... integration angular velocity calculation unit, 9a ... inertia component extraction unit, 10b ... misfire parameter calculation unit, 11b ... misfire decision section, 100 ... pumping torque component extraction device, 300 ... misfire decision device

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2008111354 [0004]
• JP 2014199040 [0004]

Claims (10)

A misfire detection device for a single cylinder engine comprising: Means (4a, 4b) for detecting an angular velocity at each crankshaft angle from an intermediate course wave pulse period; Means (7b) for calculating a relative angular velocity at each crankshaft angle with respect to a reference angular velocity detected in the vicinity of an upper compression dead center and near an upper exhaust dead center of the engine based on the angular velocity at each crankshaft angle; Means (8b) for integrating the relative angular velocity within a given crank angle range to calculate an integration angular velocity for each of an expansion stroke and an intake stroke; and Misfire parameter calculation means (10b) for calculating an integration angular velocity resulting from the combustion torque, the integration angular velocity, the reference angular velocity and a specially detected pumping torque component and for determining the calculated integration angular velocity as misfire parameters. Misfire detecting device for a single-cylinder engine according to Claim 1 wherein the misfire parameter calculating means includes: means for removing an integration angular velocity component resulting from the pumping torque from the integration angular velocity in an expansion stroke to calculate a first integration angular velocity after removal; Means for removing an integration angular velocity component resulting from the pumping torque from the integration angular velocity in an intake stroke to calculate a second integration angular velocity after removal; and means for subtracting the second integration angular velocity after the distance corrected with a ratio between the reference angular velocities in the expansion stroke and the intake stroke from the first integration angular velocity after the distance to determine a misfire parameter. Misfire detection device for a single cylinder engine according to Claim 1 or 2 further comprising means (6b) for removing a first angular rate fluctuation component that may occur in a vehicle-carried engine from the result of the detection of the angular rate, the means that calculating a relative angular rate calculating a relative angular rate aimed at an angular rate, from which the first angular velocity fluctuation component is removed. Misfire detection device for a single-cylinder engine according to one of the Claims 1 to 3 , wherein the first angular velocity fluctuation component is an angular velocity fluctuation component resulting from the load torque applied by a tire or an accessory of an engine-driven vehicle and the friction of a sliding part of the engine. A misfire detection method for a single cylinder engine comprising: Detecting an angular velocity at each crankshaft angle from an inter-crankshaft pulse period; Calculating a relative angular velocity at each crankshaft angle with respect to a reference angular velocity detected in the vicinity of an upper compression dead center and in the vicinity of an upper exhaust dead center of the engine based on the angular velocity at each crankshaft angle; Integrating the relative angular velocity within a given crankshaft angular range to calculate an integration angular velocity for each of an expansion stroke and an intake stroke; and Calculating an integration angular velocity, which results from the combustion torque, from the integration angular velocity, the reference angular velocity and a specially detected pumping torque component and determining the calculated integration angular velocity as a misfire parameter. Misfire detection method for a single-cylinder engine according to Claim 5 , further comprising: removing an integration angular velocity component resulting from the pumping torque from the integration angular velocity in an expansion stroke to calculate a first integration angular velocity after removal; Removing an integration angular velocity component resulting from the pumping torque from the integration angular velocity in an intake stroke to calculate a second integration angular velocity after removal; and subtracting the second integration angular velocity corrected with a ratio between the reference angular velocities in the expansion stroke and the intake stroke after the distance from the first of the integration angular velocity after removal to determine a misfire parameter. Misfire detection method for a single cylinder engine Claim 5 or 6 , further removing a first angular velocity fluctuation component that may occur in a vehicle-mounted engine from a result of the angular velocity detection, calculating a relative angular velocity aimed at an angular velocity from which the first angular velocity fluctuation component is removed. Misfire detection method for a single-cylinder engine according to any one of Claims 5 to 7 wherein the first angular velocity fluctuation component is an angular velocity fluctuation component resulting from the load torque applied by a tire or an accessory of an engine-driven vehicle and the friction of a sliding part of the engine. Vehicle in which a single-cylinder engine is installed, comprising: Means for detecting an angular velocity at each crankshaft angle from an inter-crankshaft pulse period; Means for calculating a relative angular velocity at each crankshaft angle with respect to a reference angular velocity detected in the vicinity of an upper compression dead center and in the vicinity of an upper exhaust dead center of the engine based on the angular velocity at each crankshaft angle; Means for integrating the relative angular velocity within a given crankshaft angular range to calculate an integration angular velocity for each of an expansion stroke and an intake stroke; and Misfire parameter calculating means for calculating an integration angular velocity resulting from the combustion torque, the integration angular velocity, the reference angular velocity and a specially detected pumping torque component and for determining the calculated integration angular velocity as a misfire parameter. Vehicle into which a single-cylinder engine is based Claim 9 is installed, the misfire parameter calculating means including: means for removing an integration angular velocity component resulting from the pumping torque from the integration angular velocity in an expansion stroke to calculate a first integration angular velocity after removal; Means for removing an integration angular velocity component resulting from the pumping torque from the integration angular velocity in an intake stroke to calculate a second integration angular velocity after removal; and means for subtracting the second integration angular velocity after the distance corrected with a relationship between the reference angular velocities in the expansion stroke and the intake stroke from the first integration angular velocity after the distance to determine a misfire parameter.

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