JPS6022042A - Apparatus for detecting engine temperature - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an engine temperature detection device suitable for electronic fuel supply/control amount for internal combustion engines, and in particular, This invention relates to a device that outputs an output that is relatively close to the actual engine temperature even after a sensor abnormality occurs in the event that a temperature change occurs.

(Background of the invention) Conventionally, patent applications filed in 1982-. Publication No. 78725, 97452
In the above publications, an electronic fuel feed rate control device for an internal combustion engine is disclosed. This electronic fuel supply control device indicates the engine rotational speed, 1' engine leap lj] rotation speed signal, and the intake air m, 1 indicates the basic fuel m to be supplied to the engine using an intake air hanger No. 18, etc. In addition, an engine temperature signal indicating the engine cooling tone or tune, and an intake air temperature signal indicating the intake air temperature.

(The above-mentioned basic fuel amount is corrected using an idle signal indicating whether or not the interlayer is in an idling state, and fuel is supplied to the engine according to this corrected fuel amount.

In addition, the conventional Japanese Patent Application Publication No. 5/1999/! -141926 Tan Publication states,
An engine humidity detection device suitable for the electronic fuel supply restriction (l'II device) is disclosed. If
After the Senna abnormality occurs, a preset constant value (
For example, it is designed to output a temperature 1 good signal (normal engine temperature sensor) after warm-up is completed, and if this is used in an electronic fuel supply amount control device, it will detect -C due to an abnormality in the engine temperature sensor.
11; It was possible to reduce the possibility of errors occurring in the correction of the fuel supply level corresponding to the old temperature.

However, in this conventional engine temperature detection device, if an abnormality occurs in the engine hot water level sensor, then the temperature will be constant at 1-3 (for example, A3 in the steady state after warm-up).
4) Since the sensor outputs a signal that is considerably higher than the normal detected temperature, as shown in Fig. 1, if a sensor abnormality occurs during warm-up when the engine temperature is rising, as shown in Fig. 2, The output of the temperature 1/good detection device suddenly becomes Δ], and as a result, a large error occurs between the output and the actual engine temperature shown by the dotted line C in the figure.

Therefore, if the configuration is such that the fuel supply amount is corrected based on the output of the temperature detection device, the warm-up has already been completed even though the temperature of the I-temperature is still low due to the warm-up process. The temperature of the ``C engine has risen sufficiently and it is mistaken for Iζ etc., and the fuel amount increase correction is not performed when the engine temperature is low, so the air-fuel ratio decreases and the exhaust purification performance decreases.

There were problems such as deterioration of tW functionality and drivability, and furthermore, engine stalling was more likely to occur.

(Purpose of the Invention) This invention was made in response to such conventional problems. If this occurs, a signal close to the actual interlayer temperature will continue to be output even after the abnormality has occurred.
Puru J: The aim is to provide a temperature sensor equipped with a sea urchin.

(Structure of the Invention) FIG. 3 is a claim correspondence diagram for explaining the structure of this IFr light.

In the same figure, Onmaro Hinri 100 detects the humidity of the engine directly or indirectly detects the temperature of the cooling medium, lubricating oil, etc.

-ll'i Storage means 101 temporarily records the latest detection output of the sensor 100. It's a must have.

The abnormality detection means 102 detects the
Based on the detection output of λ, abnormality of the sensor is determined.

(The engine rotation speed detection means 103 is a device C that detects the rotation speed of an engine (not shown).

The first interlayer state determining means 10/I detects the above-mentioned L error! At this time, it is determined whether the abnormality occurred during (during warm-up between stages or after warm-up Ijl) based on the temporarily stored value of the output immediately before the abnormality.

The output selection means 105 outputs the actual detected value of the sensor as the engine temperature when the senna 100 is determined to be normal, while it is determined that the sensor is abnormal and the engine is being warmed up after the senna abnormality occurs. After the Senna abnormality occurs, the predetermined predicted detection value J3 is determined at each point in time, which is determined by the SEN V detection value immediately before the SEN abnormality occurs and the integrated engine speed value after the SEN + J abnormality occurs. is output as the engine temperature instead of the actual detected value.

(Description of Embodiment) A preferred embodiment of the present invention will be described in detail below with reference to the drawings from FIG. 4 onwards.

FIG. 4 is a block diagram showing the overall system configuration of an electronic fuel supply amount control device employing the temperature detection device according to the present invention. As shown in the figure, this electronic fuel supply amount control device includes a ROM 1 that stores system programs, etc. The system is mainly composed of a micro combi coater consisting of a RAM 2 which is used as a backing, an I10 interface Jice 3, and a C1) U4 which serves as an overall control layer for these.

110 interface 3 contains the output of the engine speed sensor 5, the output of the I layer temperature sensor 6 d3J: and the basic combustion 1.
廿→ノ(
Example 1. (, 1 Aflosenri, etc.) is supplied.

Here, as the engine speed sensor 5, for example, output pulses from a well-known crank angle sensor can be calculated by a counter that increments 01 every time.

In addition, the engine warm stone sensor 6 is connected to the cold IJI of the engine, for example.
A temperature sensitive resistance element 6'1, such as a reamister or the like, disposed at a predetermined portion of the medium path, a combined resistance value of this temperature sensitive resistance element 61 and a fixed resistance 62, a fixed resistance 63, a base W, and a lightning voltage c. A voltage dividing circuit with a voltage division 'J-7, ) , J:
It is composed of a resistor 6/I, 21, 4, 5, and an integral circuit that removes the noise output component of the JJ circuit. It is composed of - (is.

Here, for example, a relationship not shown in FIG. 6 is set between the output voltage vi of the sensor 6 and the engine temperature, that is, in the example of FIG. If the range of variation is 1°L=TH, the value of the output Vi of the normal humidity a sensor 6 is set to vary linearly between the boxes of VL-V'H.

In addition, the non-volatile menu 7 is controlled by the CPU 4.
AD-WRIT'E is possible and CP
The configuration is such that the stored information is retained even after the power to U4 is cut off. Specifically, for example, FΔM
It can be configured as ΔM, etc. by using semiconductor nonvolatile memory such as O8, MΔS, and MNO3'8, or by directly backing up the power supply C from the battery without going through an ignition switch.

Further, the temperature sensor abnormality alarm device 8 employs various configurations including auditory alarm means such as a combination of a boogie or a voice synthesis LSI and a speaker, a visual alarm means such as a lamp, an 0R-r, and a tactile alarm means. In other words, if an abnormality occurs in the temperature sensor 6, an alarm is issued immediately or in response to a predetermined operation.

Further, the fuel injection valve drive circuit 9 drives the drive coil 10 for the fuel 0/1 valve in response to a predetermined signal from the 1710 interface 3.

It should be noted that various specific configurations of the fuel r3+ injection valve are well known, and therefore description thereof will be omitted.

Next, FIG. 5 shows the system block necessary for the operation of this electronic second eye z1 supply suspension control device.
? -1-, the operation of this embodiment device will be systematically explained. 'ch J3, this block] 21g is a program C1 so-called 115 that is started every predetermined time.
An inter-synchronization method is used.

j, su゛, step <1), 1,10 interf]
, the output of the inter-stage rotation speed lens 1-5 via the chair 3.

++l r! The outputs from the various sensors mentioned above are read in from the micro-minimum unit 6, and each of these read data is CP LJ,
4 to each register provided in the working area of the RAM 2.

It is assumed that the output of the inter-stage temperature sensor 6 is stored in the current temperature register r<1-+, and the output of the engine rotation speed sensor 5 is stored in the current rotation speed register RN.

Next, in steps (2>, (3)), the current thirst T1 indicated by the stored contents of the current thirst register 1 (11) is set to the lower limit temperature a - r that can be detected when the engine humidity sensor 6 is normal.
A determination is made as to whether it is lower than L or higher than J3 and upper limit eddy current 1'HJ:.

Here, if the first interlayer temperature sensor 6 is normal, the execution results of these steps (2> and (3) are both No, and then step (4) is executed and the second stage shift register FIFO (First
in J:1rsl Qut) The contents of the current Takimaro register R-1-+ are written to the stack.

On the other hand, if the engine temperature sensor 6 is abnormal,
Either step (2) or step (3) must be Y.
ES, and then step (5) is executed, and the sen+Jn normal flag F T provided in the non-volatile memory 7 is
is set to 1''.

Therefore, if the power to the microcomputer is cut off after 11, the contents of the sensor abnormality flag FT are retained.
For example, when a mechanic lifts 111 cars and reads out the contents of this sensor 1 abnormality flag FT using a predetermined system program, it is possible to read out the contents of this sensor 1 abnormality flag FT at the time of child maintenance (even if no sensor abnormality is observed in the past). 1) If an abnormality occurs, it can be discovered during maintenance.

Next, when step (6) is executed, the immediately preceding detection data taken out from the FIFO stack is transferred to the immediately preceding eddy current register R-ra.

Next, when step (7) is executed, the memory contents of the irl pre-temperature register R'I'o are shown as the result of the sensor 1! i before 4iJI I! Based on whether J Taki degree 1-0 is lower than Nawate (engine humidity after completion - [S),
It is determined whether or not the sensor abnormal light output Il''j is being warmed up since it is 1 before the completion of warming 1j!i.

Here, C', if the sensor abnormality flag is after the completion of warm-up, the execution result of step (, 7) will be NO, then step (8) will be executed, and the current temperature register R will be returned.
'1-+ corresponds to the normal temperature Ts at the end of warm-up completion J
1'-T is transferred, and then with the execution of step (4), the contents of this current temperature register R-r+ are transferred to FI
Pushed onto the FO stack.

On the other hand, if the sensor abnormality flag is warm (warm), the result of step (7) is YES, and step (9) is then executed to perform engine temperature prediction processing.

In this engine temperature prediction process, the temperature is below the temperature immediately before the occurrence of sensor abnormality, which is stored in the immediately preceding temperature register R0. Based on the engine speed N stored in the engine speed register RN,
The current predicted temperature of the engine can be determined by the following equation.

Predicted temperature -TO+ -N...(1) Here, equation (1) for r; d above is based on the engine temperature during warm-up as shown by the solid line in Figure 7. It is determined based on the assumption that it increases linearly in proportion, and the value of the coefficient is determined experimentally based on the reading frequency of each input information performed in step (1). .

Then, the predicted temperature of 1, which is determined by equation (1), is 1 good (,1
, current (J: stored in temperature register 1 1° 1).

Next, when step (10) is executed, it is determined whether the predicted temperature of the engine indicated by the stored contents of the current hot water temperature register R-"+ is equal to or higher than the constant temperature 1-s after warm-up is completed. Based on C, a prediction is made as to whether or not warm-up of the engine has been completed.

Here, if it is predicted that the engine will have one loss (1), the execution result of step (10) will be YES, then step (8) will be executed, and the current temperature register 1 < Data corresponding to the interlayer temperature US after the completion of warming I is written in T1.

If it is predicted that it is warming up, the execution result of step (10) will be NO, and then -("Step (4) will be executed, and the predicted One i-ta corresponding to the temperature of the current machine 1'!! is sent.

This J, Uni, Ifil! Q tilt anti-unley 6
If it is normal, let, current lag) currency register R-I'
+ is always written with data corresponding to the actual detected temperature.

On the other hand, when a sensor abnormality occurs, the following two operations are performed depending on whether the sensor abnormality flag is set during warm-up or after warm-up is completed.

However, if the sensor abnormality occurs during a warm fire, as shown in Figure 7 (1), during the period C when the sensor abnormality is predicted to be completed, it will be proportional to the cumulative rotational speed. In the case of 11 where warm-up is predicted to be completed, a signal corresponding to the normal temperature Ts after warm-up is output is output. .

Further, if a sensor abnormality occurs after the completion of warm-up, a signal corresponding to the normal temperature 1-s after the completion of warm-up is output immediately after the sensor abnormality occurs.

Therefore, the error between the Ichiko 1111 engine wetness indicated by the solid line in Fig. 7 and the actual engine temperature indicated by the dotted line is sufficiently small.
is limited to q) lj even after sensor abnormality occurs.
It's close to La Seki's fever (it will output direct and continue to be output).

Next, in steps (11) to (15), the electronic fuel supply opening control process is performed at T5, but since this process is already known in the literature of 4Φ, I will give an example. It is explained during the song.

In the super-fup (11), the operation i of y; (main sentry single equivalent pulse width 11) is performed. In this play, T.
-L Anno 0- t? (intake air mQ)
512, determine the engine speed N based on the engine speed sensor, and based on these, calculate the amount of air Q / N taken into 1 intake ゛F (?), and further calculate the fuel flow rate. The basic pulse width 1p is determined in proportion to Q/N, taking into consideration the flow rate characteristics of the pulse r.

Next, in step (12), it is determined that (j1 relative humidity increase n1 correction coefficient 1<TW).
In order to determine the t coefficient 1<TW, the memory of the current temperature register R1 described above is used. The purpose of this correction coefficient is when the engine is cold and hot (increasing fuel for combustion stabilization, exhaust purification, warm-up performance, vehicle QV, 'l!
Things that improve I and prevent engine stalls C
be.

Next, in step (13), four calculations are performed for each type of correction coefficient. Other correction coefficients include the following.

1<AS: Increase at startup 1B correction KAt; Increase after idling K 14 R; Mixture ratio correction KFC: Fuel cut 1~ ]-8; Voltage correction Next, in step (14), Based on the basic sentry suspension equivalent pulse width 1'' p and the correction coefficient of the platform scale, the pulse width 1° out of the normal injection IJJ flll can be calculated from the following equation.

T Ost −= T 11 ・ (1+l<TW →
-K A S 1 K Δ 1+1
K F C・α-t Ts='Ie<Ij effect injection suspension)+13 Next, in step (15), the fuel nQ river control signal is used to inject the fuel based on the output pulse width 1-out obtained above. Based on the output to the valve drive circuit 9, the coil 10 of the fuel injection valve is driven, and the desired fuel level is delivered to the engine.
I'm glad that the suspension will be provided.

Next, in step (16), the non-volatile memory 7
II II II
A determination is made as to whether or not the number is t-6.

Here, if an abnormality alarm has occurred in the past, the execution result of SJ-TS 7 (16) will be Y E'S, and then Slap (17) will be executed. A predetermined alarm output is issued to the device F!r8, and based on this, the -C kidney reporting device 8 causes an alarm to occur in the -C temperature range 9. Or, it will be tactile information.

Thus, according to this embodiment, when an abnormality occurs in the engine temperature L, it is possible to continue outputting a temperature close to the actual engine temperature even after the occurrence of the direct operation. (, Applying this to the well-known electronic fuel injection suspension control device gate, and ()
What institutions are needed for the project? ! 11 If we were to use a different detection means, it would be obvious that an abnormality had occurred in the warmer temperature (-6). ,
It is possible to perform normal correction processing according to the engine temperature.

Furthermore, if an abnormality occurs in the temperature sensor, this can be immediately alerted to operation, and past abnormalities in the temperature sensor can also be confirmed during maintenance listings, etc.

The program used to explain the above embodiment is a so-called time synchronized program that starts at predetermined time intervals, but instead of this, an angle synchronized program that starts a program at predetermined (interlayer rotation angles) may be used. It's okay.

In that case, the predicted temperature can be calculated as follows instead of the above equation (1) for calculating the predicted temperature.

Predicted temperature - TO + l (d... (2) In other words, the temperature rise for each predetermined engine rotation angle is a constant Kd, that is, the predicted temperature during warm-up is proportional to the interlayer rotation speed product sieve value and is a straight line. I will continue to improve my skills.

J3, the value of the constant Kd is the program startup cycle 111,
In other words, this can be determined experimentally based on how often the program is started. In the above embodiment, the PIFO stack was used as a means for temporarily storing the latest detection horn of the engine temperature sensor, but instead of this, the 2
Even if you set up a stage shift 1 register and record the output of the interlayer thirst level 6 as 10/Y in this shift register, 1q<, and further engine memory. Hinri 6
The output side of the is branched into two systems, and one is directly connected to
10 interno 1 is input to chair 3), and the other one goes through the ab[]g Chikanobu circuit a little) 1y) and then similarly goes to 110 interno 1 - chair 3, causing a sentry abnormality. The delayed detection signal may be read at the 01 point.

In addition, in the 1jlJ+iE embodiment, [
? IQ
1- J, sea urchin lζ, which determines that H, 'l-L is out of range, replaces -1, limit 5 no, one of the lower limits () and determines ¥shi always 1 node. But it's fine, and even better (
It is also possible to determine whether 51<normally based on the fact that the rate of change of the detection horn of J- exceeds a predetermined value (10).

In addition, 1) Embodiment-r IJ: As a means of detecting the engine rotational speed, an IR was constructed using a crank angle sensor V and a counter that counts the child's output. Step t) Based on the signal from the rotary optical rotary encoder (the number of rotations between the pawls may be detected).

In addition, in the above-mentioned embodiment, the sensor detection value immediately before the sensor abnormality occurs and the integrated value of the engine rotation speed after the sensor abnormality occurs are used to predict and overturn the predetermined detection value at each point in time. We used a method of substituting the number of revolutions into a mathematical formula representing a straight line, but instead of this, each integrated value of number of revolutions corresponds to the product n value. It is of course possible to predict the engine temperature using the above method, and furthermore, in this example, it is assumed that the engine temperature rises linearly during warm-up. Of course, it is possible to create a curve near the detection curve 11] and perform more accurate approximate predictions.

In addition, 1) In the IC example, the temperature detection device according to the present invention was applied to an electric lighting type fuel 1 supply suspension control device, but the present invention 1
The application of 4 necks is not limited to this and there is no C. For example, depending on the temperature of the machine 1n, when starting the cold JJ 77n 1+11
A cold N1 water temperature control system that controls the water temperature, and a warm water temperature control system that controls some kind of output depending on the humidity level of the water temperature control system. It is.

(Effects of the Invention) As is clear from the explanation of Example 1 below, if this invention is used, an abnormality will occur in the engine temperature during warm-up! In the 9th stage, it is possible to continue to generate an output relatively close to that of the CBL Bozeki for each directly operated generator, and this can be applied to a well-known electronic fuel supply suspension control system, for example, on the A31J.
(In order to correct the interstitial temperature increase, please use the interstitial humidity detection means properly.) !Supplementary '+I' t
ui fy > to reduce the number of shaped tubes as much as possible, and eliminate problems with conventional) 11A detection devices.1. : 111 air purification properties due to the dilution of the air-fuel ratio, making it warmer! This has the effect of preventing poor drivability] and also preventing the occurrence of engine stall.

[Brief explanation of the drawings] Figure 1 is a graph showing the relationship between the integrated rotational speed value (1) and the interlayer detection value when the engine temperature sensor is normal.
Fig. 52 is a J graph showing the relationship between the integrated rotational speed value and the corrected output value applied to a conventional engine temperature detection device, Fig. 3 is a diagram corresponding to claims that do not cover the present invention, and Fig. 4 is a graph showing the relationship between the integrated rotational speed value and the corrected output value applied to a conventional engine temperature detection device. The system configuration of the applied electronic fuel supply and clearing control system is shown below.
-Block diagram, Fig. 5 shows the configuration of the system program executed by the control microcomputer of the electronic fuel supply amount control device Tf to which the present invention is applied. FIG. 7 is a J graph showing the relationship between the rotational speed integrated value and temperature output of the temperature detecting device N according to the present invention. 1...RO, M 2...RAM 3...I10 interface 4...CPLI 5...1; 31 function rotation speed sensor υ 6......(interlayer temperature Senza 7...
...Non-volatile meter 8...Temperature sensor abnormality alarm device 9...
...Fuel injection valve drive circuit 10 ... Fuel 1'8I injection valve coil 100 ... Warm stone sensor 101 ... Temporary storage means 102 ... Temperature abnormality detection means 103 ... 1-layer rotational speed detection means 104 ... Engine state determination means 105 ... Output selection means Special v1 Applicant 1] San Jidosha Co., Ltd. Figure 5

Claims (1)

[Claims] (1) A sensor that detects the hot stone of the engine directly or indirectly through the temperature of the cooling medium, lubricating oil, etc.; Temporary opening means that temporarily stores the latest detection output of the sensor; Sensor abnormality determination means for determining abnormality of the sensor based on the detection output of the sensor; and: l! ,l! an engine rotational speed detection means for detecting the rotational speed of the gate; an engine state determining means for determining whether the engine is being warmed up or after warming up; If it is determined that the engine is warming up when the sensor abnormality occurs, the sensor detection value immediately before the sensor abnormality occurs and the integral value of the engine rotation speed after the sensor abnormality occur. 1. A temperature detection device for an engine, comprising an output selection means for outputting a predetermined predicted detected value at each determined time point as an interlayer temperature instead of an actual detected value.