JPS60253943A - Torque detection device for internal combustion engine - Google Patents

Abstract

PURPOSE:To detect a momentary torque with good accuracy by performing a calculation with the corrected value of the detected value of the pressure variation of the inside of a cylinder by the reference value of the inner pressure of the cylinder and with the detected crank angle and by outputting a signal according to the net thorque generated by an engine. CONSTITUTION:A pressure detecting means 1 detecting the pressure variation of the inside of a cylinder of an internal-combusution engine is provided and the means 1 is constituted by providing a peizoelectric type pickup between an ignition plug fitted to each cylinder and the head part of engine. The pressure variation detected electrically is fed to a pressure correcting means 2 and the inner pressure of cylinder is corrected with the pressure level of a crank angle set up in advance by the inner pressure of cylinder as a reference value. On the other hand the crank angle of an engine E is detected by a crank angle detecting means 3. The output of the means 2 and the output of the means 3 are fed to a torque calculating means 4 and converted into a net torque generated by the engine E by the means 4 and the signal according to the net torque is outputted. A momentary torque can be thus detected with good accuracy.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention is used for controlling, designing, and other arbitrary applications of internal combustion engines, and corrects the Schilling internal pressure of the engine using a reference value to reduce the torque generated by the engine. The present invention relates to a torque detection device for an internal combustion engine.

"Prior Art" Controlling an internal combustion engine, for example, optimally controlling the air/fuel efficiency or ignition timing of each cylinder, makes it possible to achieve low fuel consumption without reducing the output of the vehicle. Furthermore, responsiveness (so-called response) plays an important role in internal combustion engines. Engine torque is effective information for performing these controls.

Conventionally, there are several methods as such a torque detection device for an internal combustion engine. One method is to install a pressure detection element or a force meter using a strain gauge on the support part of the engine body to detect the reaction force caused by combustion pressure and indirectly measure the engine output. be. In this case, in order to prevent engine vibrations from being transmitted to the vehicle body, the engine support section is configured to include a soft spring element, and this spring and the engine body constitute a vibration system. The natural frequency of this vibration system is usually set slightly lower than the idle rotation speed.

Therefore, during transient operations such as loading or unloading, problems such as a delay in engine torque response and difficulty in transmitting high frequency components of torque occur due to soft spring deformation or low natural frequency. In addition, near the idle rotation speed, the torque detection unit detects the load due to the vibration of the vibration system consisting of the engine mass and the spring of the engine support.
Problems arise such as the output of the detector includes signals other than the a-related torque. Furthermore, since this method involves inserting a detection element or the like into the engine and its mount joint, it is affected by the tightening force of the joint, resulting in a lack of detection accuracy and reliability.

In addition to this, there are several methods of directly detecting engine output torque. In other words, it is a method of measuring information generated by the twisting of the output shaft of an engine that occurs during torque transmission.A strain gauge is attached to the rotating shaft, and the strain caused by the twisting of the shaft is detected as a change in resistance of the dage. Alternatively, there is a method of transmitting information using a wireless telemeter or the like, or a method of measuring the torsion angle corresponding to the torque of the output shaft as a phase difference of a waveform generated by an electromagnetic pickup or the like. However, since it is necessary to obtain information from the rotating body, these devices have a complicated structure, are expensive, and are heavy, making it practically difficult to use them as a torque detection device or feedback element for engine control.

In particular, torque meters using slip rings have problems such as vibration and wear of the slip ring contacts, and it goes without saying that it is difficult to withstand long-term use.

One method of directly detecting engine torque is to use a magnetic circuit to detect changes in magnetic permeability caused by torque acting on the crankshaft. This method has advantages such as being able to directly detect crankshaft torque without contact and having a relatively compact structure. However, the torque detection position must be installed between the flywheel and the cylinder closest to the 7-line wheel to detect engine torque, and the shaft must be made longer to detect the torque. 7. Bending vibration of the crankshaft using the light wheel as a mass is likely to occur, and this bending vibration causes the gap between the sensor and the crankshaft to fluctuate, thereby impairing the accuracy of this torque detection device. Furthermore, the crankshaft must have enough strength to withstand bending or torsional loads without being damaged. This means that a hardened and tempered medium carbon mechanical structural steel or a soft magnetic material such as spheroidal graphite cast iron, which is not necessarily suitable as a sensor material, is used for the crankshaft, making it difficult to put it into practical use.

Alternatively, there is a method of determining the FlV diagram by detecting the Schilling internal pressure and crank angle, calculating the indicated horsepower from the area, and obtaining the average torque for each cylinder from this, but the signal processing required to obtain the average torque is In addition to being time-consuming and difficult to calculate, this method only obtains the average torque after one cycle is completed, and it detects the engine's moment-to-moment torque, that is, transient torque fluctuations. It's not a thing. On the other hand, there is a method of obtaining a so-called torque curve showing changes in torque over time by previously detecting Schilling internal pressure and crank angular velocity and taking into account the effect of inertia of the reciprocating part. However, this method is used for torsional vibration analysis of the crankshaft, and is not suitable for use as an engine torque detection device.

"Problems to be Solved by the Invention" The present invention solves the problems of these conventional engine torque detection devices.
An object of the present invention is to provide a reliable and simple-structured torque detection device for an internal combustion engine, which is used to eliminate IIF and is capable of detecting the momentary torque of the internal combustion engine.

"Torque measurement principle of the present invention" First, the torque measurement principle of the present invention will be explained. 1st
The figure is a diagram illustrating the principle of calculating engine-generated torque for one cylinder from Schilling internal pressure Pi and reciprocating part inertia Fo in an internal combustion engine.

1a is a shilling of an internal combustion engine, and 111 is a piston.

1c is a connecting rod, and ld is a crank arm. Assuming that the Schilling internal pressure applied to the piston 1b is Pi7 and the piston area is A, the force Fp due to the gas pressure applied to the piston 1b in the vertical direction is expressed by the following equation (1).

Fp=PiA (1) The reciprocating mass is IIJy, the radius of the crank arm 1d is r,
If the length of the connecting rod 1c is 1 and the crank angular speed is ω, then
The vertical inertia force Fi is calculated up to the second-order term and becomes the following (
2) It is expressed by the formula.

Fi=-mzrω2((3)ωt+-i, 2ωt) (
2) Therefore, the total force FO applied to the piston is expressed by the following equation (3).

Fo=Fp+Fi=PiA mrecr”2(anωt
++an2ωt) (3) In this state, the torque T (torque generated by one cylinder) acting on the crankshaft in the rotational direction is expressed by the following equation (4).

T = F, ・+r(sin ωt+ 1 sin 2 ω
t) (4) The torque of a multi-cylinder internal combustion engine can be easily and instantaneously obtained by adding the torques per cylinder obtained in this way.

However, since the influence of inertial force is small compared to the Schilling internal pressure, by detecting the Schilling internal pressure with sufficient accuracy according to the present invention, a torque detection device that can withstand practical use is provided.

[Means and operations for solving the problem] As shown in FIG. A pressure correction means 2 that corrects the pressure using the pressure level of a preset crank angle as a reference value, a crank angle detection means 3 that detects the crank angle of the internal combustion engine, and an output of the pressure correction means 2 and the crank angle detection means 3. Torque calculation means 4 calculates the net torque generated by the engine E and outputs an output corresponding to the net torque.
It consists of

According to the present invention, a pressure detector for measuring Schilling internal pressure for supplying a signal to the pressure detection means 1 and a sensor for measuring the crank angle and supplying a signal to the crank angle detection means 3 are attached to the engine E. This eliminates the need for modifications such as installing a torque detector on the output shaft where the engine's output torque is transmitted or the support section where the engine's torque reaction force acts, as in the past; Torque that fluctuates rapidly can be detected by a simple method, and the above-mentioned object of the present invention is achieved.

As described above, one of the points of interest of the present invention is to provide the pressure correction means 2 that corrects the pressure level using a preset crank angle as a reference value. This component is used to compensate for changes in the pressure zero drift F and other reference values of the pressure detector due to changes in engine temperature conditions when the engine is operated at various speeds and load conditions. be. Figure 3 shows an inline 4-cylinder engine as an example. This is an example of measuring the finger pressure of the fourth cylinder of the engine, and shows that a large zero drift occurs in the pressure P due to differences in loads such as explosion and exhaust. If the torque is estimated based on such measurement results, it will not correspond to the engine torque, so the apparatus of the present invention is equipped with the pressure correction means 2 described above. In pressure sensors, changes in pressure sensitivity as well as zero drift are a problem. FIG. 4 shows the change in pressure sensitivity ΔP with respect to temperature Te+np.

The pressure sensor used was a foil Deno. Changes in pressure sensitivity due to temperature were verified in the range of -50'C to 250°C,
9 is filled in based on the test temperature of 100°C, and the variation is within ±3%. In addition, the change in pressure sensitivity over time was quite small. Based on the results of these studies, it has been determined that in order to adjust the engine torque based on the Schilling internal pressure, it is necessary to include a pressure correction means 2 that corrects the pressure level as in the present invention described above. reached the conclusion.

Figure 5 shows the experimental system to confirm this conclusion.
vinegar. Engine E is an inline 4-cylinder engine. This engine E
A foil strain gauge was affixed to the fifth journal of the crankshaft, which was fifth from the front of the engine, to measure the engine output torque, and this No. 4717 was taken out from the rotating body using an FM telemeter. The fifth journal torque measured by this foil strain gauge is shown as a solid line, and the engine torque calculation result (output of the torque calculating means 4 shown in FIG. 2) by the device configured as an example of the present invention is shown as a dotted line in FIG. 6. show.

Torque calculation results by conventional technology that does not use the present invention (second
A comparison is illustrated in FIG. 7 with the dotted line representing the output of the torque calculation means 4 in the situation 1 (including and excluding pressure corrector #9.2) and the solid line representing the above measurement results. f: tS Figure 6 and Figure 7 both show the measurement results of transient operation of the engine with the throttle valve changed from fully open to fully closed. The results measured using a conventional device that does not include the present invention do not correspond well when moving from a high load to a low load, but the torque measurement results obtained using the device of the present invention show good correspondence at both high and low loads. The effects of the present invention are clear.

"Description of an embodiment" First, a first embodiment will be described. As shown in FIG. 6, the engine torque calculated and detected by the device of the present invention based on the Schilling internal pressure is slightly larger than the torque measured at the fifth journal. This difference is tpJ5
Using the experimental system shown in Figure 5, it was confirmed that the engine output torque measured by the engine is the net torque determined by combustion minus the friction torque, auxiliary drive torque, etc. The inventor has clarified this through investigation.

Based on the results of this study, as shown in FIG. 8, the torque calculation means 4.1 of the present invention shown in FIG. A torque detection device for an internal combustion engine according to a first aspect of the present invention is provided with a torque correction means for correcting engine output torque excluding engine drive torque.

Due to its nature, the correction relational expression of the torque correction means provided in the first aspect of the present invention needs to be determined as an experimental equation for each developed internal combustion engine. Fig. 12 illustrates the relationship between the average flocking of engine output torque read by a dynamometer and the average value Tc of engine generated torque detected by the device of the present invention. Subtracting the relational expression of the torque corrector 995 shown in FIG. 8 from FIG. 9, the following expression is obtained.

To = 0.82 Tc-1, 1 (Kgm) Engine output detected using the device according to the first aspect of the present invention, which is equipped with a torque corrector Vi5 that corrects torque by calculating based on such a relational expression. The torque and the torque measured at the fifth journal are compared and shown in the lower and upper rows of FIG. 10, respectively. When both are superimposed on one figure, they match to the extent that they almost overlap. As a result of the various studies described above and the addition of the power factor, we have come to invent a device according to the first embodiment that detects rapid fluctuations in engine output torque corresponding to combustion etc. of each cylinder as described above.

Next, gA of the second implementation will be explained. From the engine torque detected by the torque calculation means 4 of the invention shown in FIG. 2 or the torque correction means 5 shown in FIG.
In order to calculate the driving torque that powers the engine, the engine torque can be averaged over time. However, in the case of a 4-cylinder, 4-cycle internal combustion engine, the -cycle ends with the combination of the intake → compression → drying → exhaust strokes of each cylinder as shown in the tIS11 diagram, and each stroke consists of an opening at a crank angle Ac of 180°. It will be held in Therefore, it is temporally impossible to control the ignition timing of the next explosion stroke or the suction stroke from the result of the driving torque based on the output corresponding to the torque at 180° opening of the explosion stroke. be. In order to solve this problem, the inventor conducted various studies and found that the driving torque is 7αTD at the top of the explosion stroke based on the characteristics of the Schilling internal pressure.
Time average value in the range of ATDC from about 90° to 100° after TDC, and 9 of the value in the range of TDC to 180° ATDC
It became clear that the ratio did not change significantly depending on the engine operating conditions, and ATDC90
After ~100°~A""I performed control with DC 180° open and found that it was floating.

Based on the results of this study, the present inventor has determined that the crank angle determined from the engine torque can be calculated using the torque calculating means 4 of the present invention shown in FIG. 2 or the torque correcting means 5 of the present invention shown in FIG. A second embodiment of the present invention has been developed, which is equipped with a drive torque calculation means that calculates the drive torque by integrating between the two.

FIG. 12 shows a second aspect of the device equipped with such a drive torque calculating means 6, in which pressure detecting means 1, pressure correcting means 2
, a crank angle detection means 3, a torque calculation and driving torque calculation means 6, and a CPU for determining the fuel injection amount to each cylinder based on the output corresponding to the driving torque of the calculation means 6.
It consists of a device 7, and a 7-well innoctor 8.

In the second aspect of the present invention, the drive torque calculation means:
The driving torque is detected based on the time average value in the range of approximately 90° to 100' ATDC from TDC of the explosion stroke.

Therefore, with the present second embodiment device, fuel injection amount control, air-fuel ratio control, ignition timing control, etc. can be quickly controlled in accordance with the engine output.

Furthermore, a third embodiment of the present invention will be explained. When the rotational speed of the engine increases by 1, inertial torque due to reciprocating parts such as the piston and connecting rod is superimposed on the engine output torque. This torque has a fluctuating component, as shown by the equation (2) above, but has no direct current component. Therefore, the purpose or effect of detecting inertial torque as engine output torque is not to improve engine power performance, but to eliminate damage caused by torsional vibration of the Zano drive system of the vehicle.

The configuration of the torque detection device for an internal combustion engine according to the third aspect of the present invention is shown in Fig. @13. This configuration is obtained by adding an inertia torque calculation means 9 between the crank angle detection means 3 and the torque calculation means 4 in the configuration of the present invention shown in FIG. 2 or FIG. The crank angular velocity is determined from the output of the crank angle detection means 3, and the inertia torque is calculated from the crank angular velocity, the crank radius, the piston acceleration determined by the connecting rod length, and the mass of the reciprocating part. Then, the calculated output is sent via the torque calculation means 4 to the torque correction hand ri5 for adjusting the net torque generated by the m torque.

The inventor of this book! The engine output torque detected by the device according to the @3 embodiment was confirmed by the experimental method shown in the m5 diagram. ! @ Figure 14 (a) shows the torque TvI when only finger pressure is taken into consideration, and Figure 14 (1)) shows the curve of torque Te when finger pressure and inertial force are taken into account, both together with the fifth journal torque.

As is clear from the above description, the device of the second embodiment effectively compensates for the inertia torque, so that the engine output torque can be detected extremely accurately.

"First Example" Embodiments of @i of the present invention will be described below based on the drawings.

FIG. 15 shows a circuit diagram of a first preferred embodiment of the torque detection device for an internal combustion engine according to the present invention. In this first embodiment, pressure fluctuations in the shilling are detected as electrical signals, the pressure at a preset crank angle is used as a reference value, this reference value is corrected to zero level, and the corrected pressure signal is Based on this, the torque generated by the engine is calculated.

! @15 Figure 15 The embodiment shown in Figure 15 shows an example in which the torque detection device for an internal combustion engine according to the present invention is applied to a four-cylinder ennon, and includes a pressure detection circuit 100, a pressure correction circuit 200, a crank angle detection circuit 300, and a torque calculation circuit. It is composed of a circuit 400.

The pressure detection circuit 100 consists of a piezoelectric pickup 101. which is sandwiched between the flame plug provided for each cylinder and the head of the Ennon. , 106. i, 11 and 116, and the amount of variation corresponding to the Schilling internal pressure is electrically detected by the mechanical vibrations applied to 111 and 116. pick amp 10
1 is connected to a non-inverting input terminal of an operational amplifier (hereinafter referred to as an operational amplifier) 103 together with a resistor 102, and the operational amplifier 103 forms an amplification circuit together with resistors 104 and 1.05, and the detection signal of the pickup 101 is amplified to detect the pressure. It is supplied to the input terminal T1 of the correction circuit 200. Pick-ups 106° 111 and 116 provided in other cylinders are similarly connected to non-inverting input terminals of operational amplifiers 108, 113° and 118 along with resistors 107, 142 and 117, and the operational amplifiers 108, 113, 11.8 Resistors 109, 110, 114, 115 and 119, 1
20 respectively form an amplifier circuit, and the pickup 106
．． 111, 116 are amplified and sent to input terminals T2. T3°T, respectively. FIG. 16 shows the pickup 101. ．． 10
6, 111 and 116 are attached to the ennon in a sectional view of one cylinder. Piezoelectric pickup 18
3 is inserted between the shilling head 181 and the spark plug 182 and is tightened. The sillage head 183 detects a voltage proportional to the fluctuation in the shilling internal pressure and takes it out through the lead wire 184. Pressure detection circuit 100 A voltage signal corresponding to the Schilling internal pressure fluctuation of each cylinder, which is an output signal of 200 will be explained.

A voltage signal corresponding to the Schilling pressure fluctuation in the first cylinder is supplied to the input terminal T1 as described later.
is connected to an input terminal of an analog switch 201 that connects and disconnects analog signals, and to a resistor 207. The output terminal of the analog switch 201 is connected together with a capacitor 202 to a non-inverting input terminal of an operational amplifier 203, and the analog switch 201 and the capacitor 202, together with the operational amplifier 203, constitute a sample-and-hold circuit that performs sampling and holding of the sample link value. . The sampling timing of this sample-and-hold circuit is a period in which the control terminal of the analog switch 201 is at a high level (hereinafter simply referred to as I4 level), and is controlled by a signal from the output terminal 1 of the crank angle detection circuit 300. The sample hold circuit is a circuit that detects a value for correcting the zero level of the signal according to the Schilling internal pressure fluctuation detected by the pressure detection circuit 100, that is, a reference value, and the control terminal of the analog switch 201 becomes H level. The pressure signal level of the period is detected and held while the control terminal is at low level. In the illustrated embodiment, the period of H level is 180°A.
TI) C~270° ATDC. Op-amp 204 has resistors 205, 206, 207 and 208
A differential amplifier circuit is also formed, and differential operation is performed between the output signal of the sample hold circuit and the signal from the pressure detection circuit 100. The output voltage of the operational amplifier 204 is supplied to the input terminal T of the torque calculation circuit 400. The signal obtained in the above-mentioned manner has a level of 180°A corresponding to the Schilling internal pressure fluctuation detected by the pressure detection circuit 100.
This is corrected so that the level during the period from TDC to 270°ΔTDC is zero.

Signals corresponding to Schilling internal pressure fluctuations of other cylinders are similarly corrected to zero level by the pressure correction circuit 200, and the corrected pressure signal of the fourth cylinder is sent to the input terminal T6 of the torque calculation circuit 400, The pressure signal of is input to input terminal T7,
The pressure signals of the third cylinders are respectively supplied to input terminals T8.

The torque calculation circuit 400 uses the pressure signal from the pressure correction circuit 200 and the signal from the crank angle detection circuit 300 to
Calculates and outputs the instantaneous torque of the engine. The torque calculation equation for a four-cylinder engine, which is the illustrated embodiment, is expressed by the following equation (5). The pressure in the first cylinder corrected by the pressure correction circuit 200 is P2. The pressure in the second cylinder is P2. The pressure in the third cylinder is set to P3. If the pressure of the #4 cylinder is P and the TDC of the 1st cylinder is the reference, the instantaneous torque T is T.
=(P, +P+-P2 Pl])Arsinωt+(P
++p, 10p, 10p 1) Ar2/21-5in2
ωt (5) However, A is the shilling bore area, r is the crank radius, p is the length of the connecting rod, and ω is the crank angular speed.

Pressure correction circuit 200 supplied to torque calculation circuit 400
The pressure signal of each cylinder from
02.4'03. ．． Addition/subtraction circuit composed of 404, 4.05 and 406, operational amplifier 408 and resistor 40
9. 410. /1. ], ],.

412 and 413, and (P, 10P, -, P2- in equation (5)
P, ) and (p + ten P 2 + P 3 + P 4
) is performed.

A voltage signal corresponding to the calculated pressure (Pl+P4-P2-P3) is supplied to one input terminal of the q-multiplier 414, and the output signal of the operational amplifier 428 (sinω[) is supplied to the other input terminal. A voltage signal corresponding to (5
) of the first term of the equation (Pl+P4-P2-P3)X(sinω
t)'@ calculation is executed. Opamp 415 and resistor 4
The inverting amplifier circuit formed from 16.417 is the multiplier 4
14 output voltage is amplified. The degree of amplification determined by the resistors 416 and 417 is the same value as the constant determined by the product of Ennon's shilling bore area A and the crank radius r in equation (5). On the other hand, the output (P, +P2+P3+P4) of the adder circuit formed from the operational amplifier 408, the resistor 409°410, 411, 412, and the resistor 413
The voltage signal corresponding to
18 inverting input terminals. The resistor 419 and the operational amplifier 418 form an inverting amplifier circuit together with the resistor 420, and amplify the voltage signal corresponding to the pressure (P, +P2+P30P,). The degree of amplification determined by the resistors 419 and 420 is the constant Ar2/21 of the equation (5), which is 5L depending on the shilling bore area A, the crank radius r, and the connecting rod width I. The output voltage of the inverting amplifier circuit including the operational amplifier 418 is the output of the operational amplifier 439 (sin2ω)
The voltage signal is input to the multiplier 421 together with the voltage signal corresponding to the voltage signal, and multiplication is performed. The output terminal of an operational amplifier 415 forming an inverting amplifier circuit is connected to an inverting input terminal of an operational amplifier 442 via a resistor 443, and the output terminal of a multiplier 421 is connected to an inverting input terminal of an operational amplifier 442 via a resistor 444. The operational amplifier 442 forms an adder circuit together with resistors 443, 444 and a resistor 445. Therefore, the operational amplifier 415 forms an inverting amplifier circuit.
(Pl+P4 P2-P+)Arsinω, which is the output of
The voltage signal corresponding to t and the output of the multiplier 421 (P
1+P20'P:++P,)Ar2/21 ・5in2
The voltage signals corresponding to ωt are added by the adding circuit to output a voltage signal corresponding to the torque generated by the engine according to the equation (5). A crank angle signal is supplied to the torque calculation circuit 400 together with the above-mentioned corrected pressure signal of each cylinder.
t) and (sin2ωL) are generated. The crank angle signal is detected by a crank angle detection circuit 300. This crank angle detection circuit 300 includes a detection disk 301 fixed directly or indirectly to the crankshaft of the engine, a magnet 302 around which a pickup coil 303 is wound, and a magnet 305 around which a pink-up coil 306 is wound. including. 360 magnetic bodies 304 are fixed concentrically near the circumferential side of the detection disc 301 at each crank angle of 1 degree, and another magnetic body 304 is fixed on the disc 301 at the second dead center position of the first cylinder with a different radius. Body 307 is fixed. Therefore, a crank angle detection signal is generated from the pickup knob coil 306 at the top dead center position of the cylinder of the first cylinder, and this detection signal is transmitted via the pan 7a 309 to the logic circuits 310, 311, 312. '313,
314, 315 and 316 reset terminals.

In addition, from Pinqua Knob Coil 303, Clan 31
4.315 and 316 input terminals. Logic circuit 310, 311, 312° 313.314, 3
15 and 316 are composed of a counter circuit, a date circuit, etc., and are operated by the output pulse signals of buffers 308 and 309. The logic circuit 310 outputs a signal that becomes H level only when the first cylinder is opened from 180 degrees to 270 degrees after the top dead center, and outputs a signal that is at H level to the pressure correction circuit 200 via the output terminal T.
The analog switch 201 is supplied to the terminal of the analog switch 201. Similarly, the logic circuit 313 receives a -I level signal between 90 degrees and 180 degrees after top dead center;
is an H level signal from top dead center to 90 degrees after second dead center,
The logic circuit 312 outputs a signal at H level between 270 degrees after the top dead center and the output terminals Tlo and T1.
1 and TI2.

It is supplied to the pressure correction circuit 200 via the pressure correction circuit 200. Further, the logic circuit 314 outputs a signal in which the 180 degrees from the top dead center from the binary point of the first cylinder is at the I level, and the signal is at the L level from 180 degrees after the top dead center to the top dead center. 315 outputs a signal that becomes H level between 90 degrees after top dead center and between 180 degrees and 270 degrees after top dead center from the 1st cylinder's dual point. From degrees” 27 after second dead center
0 degrees is L level and from 270 degrees after top dead center” 9 after second dead center
The buffer 3 outputs a signal that is at H level between 0 degrees.
It is supplied to the torque calculation circuit 400 together with the output signals of 08 and 309. A timing chart of the output waveform of the above-mentioned crank angle detection circuit 300 is shown in FIG.

Based on the signal from the crank angle detection circuit 300, the torque calculation circuit 400 calculates the above-mentioned (sinωt) and (sin2
A voltage signal corresponding to ωt) is generated. That is, the up/down binary counter 42 of the torque calculation circuit 400
2,423, R-2R resistance lug 424, and operational amplifier 425, the digital analog conversion circuit outputs an analog voltage signal corresponding to the crank angle with the top dead center of the first cylinder set at 0 degrees. . The input terminal of the up/down binary counter 422 is supplied with a digital signal for each degree of crank angle from the output terminal TIG of the crank angle detection circuit 300, and the output of the counter 422 is supplied to the input terminal of the counter 423.

Further, the reset terminal of the counters 422 and 423 is supplied with the first cylinder top dead center signal from the output terminal TI3, and the output terminal TI4 of the crank angle detection circuit 300 is supplied with the crank angle 180
A signal is provided for each degree. Therefore, the up/down binary counters 422 and 423 count up the signal for every crank angle of 1 degree from the top dead center of the first cylinder to 90 degrees after the second dead center, and from 90 degrees after the top dead center to 90 degrees after the second dead center. Count down to 180 degrees. Furthermore, count up from 180 degrees after top dead center to 270 degrees after top dead center, and - to 27 degrees after dead center.
From 0 degrees to top dead center, there is a down count. The counter 4'22. /1.23 binary output is added to 4J1. Connected to R-2R resistor ladder for IM production,
Furthermore, since it is connected to a voltage follower circuit composed of an operational amplifier 425, the operational amplifier 425 linearly rises from top dead center to 90 degrees after top dead center, and from 90 degrees after top dead center to 90 degrees after top dead center. On the contrary, it outputs a triangular wave-like i(E current voltage) that decreases linearly up to 180 degrees.

The output of the operational amplifier 425 <1 is a sine wave, <4
4261; and an input terminal of a cosine wave converter 427, and are converted into a sine wave signal and a cosine wave signal, respectively. The signal obtained by the sine wave converter 426 has a full-wave rectified waveform with one cycle of 180 degrees at the crank angle, so the operational amplifier 428. Resistance 429, 43
0,431 and an analog switch 432, and inverts the polarity of the signal of the sine wave converter 426 during the period from 180 degrees after the top dead center to the top dead center. That is, the output of the sine wave converter 426 is connected to the inverting input terminal of the operational amplifier 428 via a resistor 429, and similarly connected to the inverting input terminal of the operational amplifier 428 via a resistor 430.
28 non-inverting input terminals. Furthermore, a resistor 43 is connected between the inverting input terminal and the output terminal of the operational amplifier 428.
is connected, and the input terminal of an analog switch 432 that is turned on by an L-level signal is connected to the non-inverting input terminal,
The output terminal of the analog switch 432 is grounded. The control terminal of the analog switch 432 is connected from the output terminal TI5 of the crank angle detection circuit 300 to the H level from top dead center to 180 degrees after top dead center.
Since the analog switch 432 is supplied with a signal that is at L level from 80 degrees to top dead center, the analog switch 432
It is in an off-ON state from 0 degrees to top dead center, and is in an off-off state from top dead center to 180 degrees after top dead center. Therefore, when the analog switch 432 is in the OFF ON state, the non-inverting input terminal of the operational amplifier 428 is grounded, and the operational amplifier 428 forms an inverting amplifier circuit together with the resistors 429 and 431, and the output of the sine converter 426 The signal is reversed in polarity. Conversely, when the analog switch 432 is in the OFF 0FF' state, the operational amplifier 428 becomes a non-inverting amplifier circuit and the polarity of the signal is not inverted. In this way, from the output of operational amplifier 428! A sine waveform can be obtained based on the 11-cylinder engine.

Output terminal T l 3 of the above crank angle detection circuit 300
, operational amplifier 425. A timing chart of the output waveforms of the sine converter 426 and the operational amplifier 42B is shown in FIG. Similarly, the output of operational amplifier 425 is provided to cosine wave converter 42'7, which outputs the cosine waveform converter 42'7. The output of the converter is input to an operational amplifier 433. Resistor 434,
435, 436 and an analog switch 437, and the signal from the output terminal T1□ of the crank angle detection circuit 300 generates a cosine wave for a period of 90 degrees after top dead center and 270 degrees after α. The polarity of the output signal from converter 437 is inverted. Therefore, the operational amplifier 433 outputs a cosine waveform based on the top dead center of the first cylinder.

The sine output signal of the operational amplifier 428 is sent to the multiplier 414.
is supplied to the input terminal of multiplier 438.

The other input terminal of the multiplier 438 is connected to the operational amplifier 4.
33 cosine waveform outputs are provided and multiplied. In other words, the output of the operational amplifier 428 is (sinωL)
Since the output of the operational amplifier 433 is (cosωt), the output of the multiplier 438 is (sinωt)・(co
sωt). Furthermore, the output signal of multiplier 438 is supplied to a non-inverting input terminal of operational amplifier 439. This operational amplifier 439 forms a non-inverting amplifier circuit together with resistors 440 and 441, and the non-inverting amplifier circuit includes the multiplier 4
In this embodiment, the amplification degree is set to double so that the output signal of 38 is amplified twice, so 2 (si
nb+ 1. )・(cosωL), that is, (sin2ω
outputs a voltage signal corresponding to Operational amplifier 435]
The output of the operational amplifier 418 is supplied to the input terminal of the multiplier 421, and the output of the operational amplifier 418 (P1+P2+P:l+
Multiplication is performed as P 4 >Δr2/21.

As described above, according to this embodiment, each cylinder internal pressure fluctuation of a four-cylinder engine is detected as a mechanical vibration by the pink amplifier, and the preset crank angle level of the detected cylinder internal pressure fluctuation signal is zeroed. By applying this correction, it is possible to calculate the instantaneous net torque generated by the ennon with high precision using a simple method by performing calculations together with the crank angle signal. That is, in the first embodiment, when the engine is operated at various operating speeds and load conditions, the zero drift of the pressure detector output and other changes in reference values are caused by changes in the engine temperature conditions. However, the present invention has the advantage that these can be corrected and the instantaneous net torque of the engine can be detected with high accuracy, and that the device is highly practical.

"Second Embodiment" FIG. 19 shows the engine output torque obtained by subtracting the auxiliary drive torque and friction torque from the net torque generated by the ennon detected by the first embodiment shown in the fIS15 diagram. A second preferred embodiment is shown. The circuit configuration of this @2 embodiment will be explained in detail below. 1st
Torque correction circuit 500 in the second embodiment shown in FIG.
The output signal of the operational amplifier 442 of the torque calculation circuit 400 in the first embodiment shown in FIG. 15 is supplied to the input terminal of the multiplier 513 via the terminal T18. The other input terminal of the multiplier 513 is an operational amplifier 512 that outputs a signal inversely proportional to the engine speed, which will be described later.
output signal is provided.

Further, a signal for each degree of crank angle from the output terminal T16 of the crank angle detection circuit 300 shown in FIG. Outputs a signal with a constant pulse width determined by The output signal from the monomulti circuit 501 with a constant pulse width is input to an integrating circuit consisting of a resistor 504, a capacitor 505, and an operational amplifier 506 and is averaged. Therefore, the sub amplifier 50
The output of No. 6 becomes a DC voltage signal proportional to the number of rotations of the Ennon. In order to obtain the engine output torque, which is obtained by subtracting the auxiliary drive torque and friction torque from the net torque generated by the engine, it can be achieved by performing the correction shown in the following equation.

In other words, if the claimed output torque is hole and the net torque is Tc, this can be done using the following formula: %=ATc-B (6).

Constants A and B are functions of the engine speed, and in this second embodiment, as shown in tIS20 diagram (a), (+)), the constant A decreases to a small value as the engine speed N increases. On the other hand, since the constant B is designed to take a larger value as the engine speed N increases, correction is possible over the entire engine speed range. Since the output of the operational amplifier 506 is a DC signal proportional to the encoder rotation speed N, the resistor 506
7,508°509.510,511 and operational amplifier 51
2 outputs a voltage signal that decreases linearly as the engine speed increases, as shown in FIG. 20(a). Since the output signal of the operational amplifier 512 is supplied to the input of the multiplier 513 described above, the output of the multiplier 513 becomes a signal corresponding to ATc in the above equation (6). The output of the multiplier 513 is supplied to a non-inverting input terminal of an operational amplifier 518 via a resistor 514. Also,
The output of operational amplifier 506 is supplied to the inverting input terminal of operational amplifier 518 via resistor 516. The operational amplifier 518 constitutes a differential amplifier together with resistors 51.4, 515, 516 and 517. Therefore, the output of the operational amplifier 518 is converted from the voltage signal corresponding to ATc, which is the output of the multiplier 513, to the output of the operational amplifier 506, as shown in FIG. 20(b). It becomes a voltage signal obtained by subtracting a voltage signal that increases linearly as the number increases.

In other words, (T, = ΔTc, B
The voltage signal corresponding to As shown in Fig. 20, by correcting the net torque generated by the ennon using information that has a linear relationship with the engine speed, the engine drives the drive system excluding auxiliary drive torque and friction torque in the entire number of times. There is an advantage that the output torque of the driving engine can be increased.

"Third Embodiment" FIG. 21 shows a preferred third embodiment in which the driving torque is calculated by specifying the crank angle from the instantaneous net torque of the engine detected by the first embodiment described above. It is shown. In this third embodiment, the above-mentioned first
5. Torque calculation circuit 4 in the first embodiment shown in FIG.
By adding a drive torque detection circuit 450 and a crank angle designation circuit 350 to 10, the aim is to detect the drive torque during the explosion stroke of each cylinder and output it as an analog voltage signal. The circuit structure of this third embodiment will be explained in detail below. The embodiment shown in the fjS21 is the first
Receiving a serial output signal corresponding to the instantaneous net torque output by the 4-cylinder ennon determined by the embodiment of ttSl shown in Fig. 5, an analog signal corresponding to the driving torque is calculated by calculating the integral value at a pre-specified crank angle. The drive torque detection circuit 450 outputs the crank angle, and the crank angle designation circuit 350 designates the crank angle.

The drive torque detection circuit 450 integrates the instantaneous net torque signal at a pre-specified crank angle in order to detect the drive torque signal during the explosion stroke from the instantaneous net torque signal of the engine, and then holds the final value. △ It is output as an analog view. The output signal of the operational amplifier 442 of the torque calculation circuit 400 in the embodiment shown in FIG.
The signal is supplied to an inverting input terminal of an operational amplifier 458 via an input terminal TlB of a drive torque detection circuit 450 and a resistor 455 shown in the figure. The operational amplifier 458 and the resistor 455 are
Together with the capacitor 456 and the analog switch 457 they form an integrating circuit, the control terminal of the analog switch 457 being connected to the output of the OR date 454.

The analog switch 457 is configured such that the 01<gate 45
When the output of 4 is at H level, it is in an OFF state, and when it is at an L level, it is in an ON state.
OR day) 4.54 output performs an integral operation during the 14 level period. The period during which the integral operation is performed is a period during which the output torque of the engine acts as a driving torque, and in the third embodiment shown in Figure @21, it is set from the top dead center to 100 degrees after the top dead center. The output of the operational amplifier 458 of the integration circuit is connected to the resistor 459 because the polarity of the signal is inverted.
460 and an operational amplifier 461, and its polarity is again inverted to make it the same as the polarity of the input signal of the integrating circuit. The output of operational amplifier 461 is supplied to the input terminal of analog switch 462. The analog switch 462 has a capacitor 463 . Together with the operational amplifier 464, a sample and hold circuit is formed. The sampling timing of this sample and hold circuit is approximately 100 degrees after the top dead center immediately before the integration circuit ends the integration operation, and sampling is performed by supplying the output signal of the mono multi circuit 451 to the control terminal of the analog switch 462. be done. capacitor 452 and resistor 4
The monomulti circuit 451 whose pulse width of the output signal is determined by 53 operates on the negative edge of the signal from the crank angle designation circuit 350, and outputs a pulse signal at the I'' level for a short period of time. Further, a signal from the crank angle designation circuit 350 is supplied to one input terminal of an OR gate 454,
The other input terminal is supplied with a short-time H level pulse signal which is the output of the monomulti circuit 451, and the OR date 454 outputs a signal obtained by ORing the two signals. The output of this OR date 454 is the analog switch 457
The output of the mono multi circuit 451 is supplied to the control terminal of the analog switch 462, respectively. Therefore, the resistor 455. Capacitor 456. Analog switch 457 and operational amplifier 45
The integration operation is performed over an interval of about 100 degrees from top dead center to after top dead center by the 81I circuit consisting of 8 parts. Analog switch 462. Capacitor 463 and operational amplifier 46
The sample and hold circuit formed from 4 samples the final value of the integration interval and holds it until the next sampling.

The crank angle designation circuit 350 is included in the crank angle detection circuit 300 in the first embodiment shown in FIG. 15 described above, and designates the integration region of the integration circuit by the crank angle.

The crank angle designation circuit 350 has a disk 351 similar to that of the first embodiment shown in FIG. Magnetic bodies 354 and 355 are attached to the. Further, other magnetic bodies 356 and 357 are attached at positions axially symmetrical to the positions of the magnetic bodies 354 and 355.

Then, the electromagnetic pickup 3 in which the magnet 352 is wound
53 is arranged at such a position that a voltage is generated at 100 degrees after the top dead center when the magnetic bodies 356, 357 pass. The electromagnetic pickup 353 is connected via a buffer 361 to an input terminal of a 7-resob 70-tub 363.

Further, another magnetic body 360 is fixed to the disk 351 at a position approximately in the center of the magnetic bodies 355 and 356 having different radii, and a signal is generated by a pink-up coil 359 wound around a magnet 358. The pickup coil 359 is connected to the pan 7.
7362 to the reset terminal of the 7-rip 70-band 363. The flip 70 knob 363 operates according to the truth table shown below, and applies a positive voltage during the period from the top dead center of each cylinder to 100 degrees after the top dead center, and otherwise applies O[:
V] and sends its output to the monomulti circuit 45.
1 and to the input of OR gate 454.

7 linop 70 knob 363. above table. Mono multi circuit 451
．． , the output waveform of the O'R date 454 and the output terminal TIB of the operational amplifier 442 of the first embodiment shown in FIG.
A timing chart of the output waveform in is shown in FIG.

Therefore, in this third embodiment, the instantaneous net torque of Ennon, which is the output of the operational amplifier 442 shown in FIG.
Since the area of the 00 degree section (the shaded area in Figure 22) is calculated and output as an analog serial signal, the fuel injection amount of the engine is determined based on the drive torque signal obtained for each cylinder's intake stroke. This has the advantage of being able to detect the Ennon output, perform quick control over the monthly response, and use it as a feedback signal for the Ennon output.

"Fourth Embodiment" FIG. 23 shows the above-mentioned tAi, and the first embodiment shown in FIG. τj
A fourth preferred embodiment is shown in which the instantaneous output torque of the Ennon is detected and outputted by adding the following.

According to the first embodiment shown in FIG. 15 described above, the cylinder pressure fluctuation is detected as an electrical signal, the pressure level at a preset crank angle is corrected to zero, and the correction is performed based on the corrected pressure signal. shows a means for conveniently detecting the instantaneous net torque of the engine. In the first embodiment, since the influence of the piston acceleration determined by the crank angular velocity, crank radius, and connecting rod length and the inertia force due to the mass of the reciprocating part is not taken into account, the torque detection accuracy is low, especially in the high engine speed range. Getting worse. That is, in the case of a four-cylinder engine, the inertia torque Ti is expressed by the following equation (7), where the mass of the reciprocating part is %, the crank angular velocity is ω, and the crank radius is r.

Ti=-2m7ecω2r2・5in2ωt (7) Since the crank angular speed ω, which is a function of the Ennon rotation speed, is introduced into the equation as a squared term, a large inertial force acts at high rotations, and the fuel torque due to Schilling internal pressure is affected. It is necessary to take inertial torque into consideration. Therefore, by adding an inertia torque calculation circuit 600 for detecting inertia torque and adding the output signal of the inertia torque calculation circuit 600 to the output signal of the embodiment shown in FIG. An advantage is that the detection device is configurable.

The circuit configuration of the fourth embodiment shown in FIG. 23 will be described in detail below. The same reference numerals as in FIG. 15 indicate the same parts. Pressure detection circuit 100. Pressure correction circuit 200. The crank angle detection circuit 300 and the torque calculation circuit 400 have the same configuration and operation as the first embodiment shown in FIG. 15. Crank angle detection circuit 300 and torque calculation circuit 40
The output of 0 is supplied to the inertia torque calculation circuit 600.

Up/down binary counters 601 , 602 . of the inertia torque calculation circuit 600 . The output of the digital to analog conversion circuit consisting of the R-2R resistor lug 603 and the operational amplifier 604 is input to the operational amplifier 607 via a sine wave converter 605 and a cosine wave converter 606, respectively.
．． Resistance 608, 609.610. analog switch 61
1, an operational amplifier 612, resistors 613, 614, 615 . The signal is supplied to a second polarity inversion circuit composed of an analog switch 616. The outputs of the operational amplifiers 607 and 612 are multiplied by a multiplier 617, and further multiplied by the operational amplifiers 618 . It is supplied to a non-inverting amplifier circuit consisting of resistors 619° and 620°. In the above, the operational amplifier 618 is used to perform the same configuration and operation as the first embodiment shown in FIG.
A non-inverting amplifier circuit including the above outputs an analog voltage signal corresponding to 5in2ωL. The output of the operational amplifier 618 is
It is supplied to one input terminal of multiplier 626. In addition, the output terminal T 1g of the crank angle detection circuit 300 is connected to the input of a frequency-voltage conversion circuit 621, and the frequency-voltage conversion circuit 621 converts the frequency of the signal for each degree of crank angle into an analog voltage. It is output as a voltage signal corresponding to the crank angular velocity ω. Further, the signal p- corresponding to the crank angular velocity ω is supplied to the two-button circuit 622, and is converted into a signal corresponding to the second crank angular velocity signal, that is, Q2. The output of the two-button circuit 622 is supplied to the inverting input terminal of an operational amplifier 623 via a resistor 624, and the resistor 624, together with the operational amplifier 623 and the resistor 625, forms an inverting amplifier circuit.

Since the amplification degree of the inverting amplifier circuit determined by the resistors 624 and 625 is set to 12 mr2 in the equation (7), the operational amplifier 623 has a value of -2 "nω2 r 2
Outputs an analog voltage signal corresponding to the The operational amplifier 6
The output of 23 is supplied to the other input terminal of the multiplier 626 and multiplied with the voltage signal corresponding to sin 2ω1, which is the output of the operational amplifier 618. Therefore, multiplier 626 is -2 which is the inertia torque of the four-cylinder engine.
An analog voltage signal corresponding to +nω2r2sin2ωt is output.

The output of the multiplier 626 is supplied to the non-inverting input terminal of an operational amplifier 627 via a resistor 629, and the torque calculation circuit 4
．． A voltage signal corresponding to the combustion torque derived from the corrected Schilling internal pressure signal, which is the output of 00, is similarly supplied to the non-inverting input terminal of operational amplifier 627 via terminal T18 and resistor 628.

Another resistor 630 is connected to the non-inverting input terminal of the operational amplifier 627.
is connected between ground. Furthermore, a resistor 631 is connected to the inverting input terminal of the operational amplifier 627, and a resistor 632 is connected to the ground.
are respectively connected between the output terminals T21, and the resistors 628
, 629 and 630 form a non-inverting adder circuit. Therefore, the voltage signal corresponding to the combustion torque output from the torque calculation circuit 400 and the voltage signal corresponding to the inertia torque output from the multiplier 626 are added, and the serial voltage corresponding to the output instantaneous torque of the four-cylinder engine is It is output from the operational amplifier 627 as a signal.

As described above, according to the fourth embodiment described above, inertial torque can be taken into account, and instantaneous engine torque can be detected using only finger pressure by attaching a simple pressure detector and a crank angle detection sensor to the engine. This method has the advantage of being able to accurately detect the entire rotation range of the engine, from the low rotation range that requires consideration to the effect of the inertial force of the reciprocating parts.

[Fifth Example, 1 The fifth example of the present invention will be described below. In this fifth embodiment, the device is constructed using a microprocessor sensor.

FIG. 24 is a block diagram of the fourth embodiment.

711a, 711. b is a pressure transducer, 712 is a crank angle detector, 713a+713b is a charge amplifier, 714
is an F/v converter for calculating the crank angular velocity from the crank angle. 715 is a Δ/D conversion device consisting of an A/D conversion section 716 and an input/output control section 717;
is the central processing unit, 7191iRAM, 720 is the RO
M, 721 is an output device.

FIG. 25 shows an example of the configuration of the A/D converter 716 shown in FIG. 24. 731a-7311+.

732 and 734 are sample and hold circuits, 733 is a multiplexer, 735 is an A/D converter, and 736 is an A/D
This is a conversion control circuit. 1st cylinder dead, α signal is A
The 1 degree crank angle signal C is used as a sampling signal for the A/D converter 716 as a signal for the A/D converter 716 .

The A/D conversion control circuit 736 outputs Schilling internal pressure A.

Signals E, , E2 . for simultaneously sampling and holding A2 and crank angular velocity B. E, multiplex] A control signal F of the multiplexer 733, a signal G for sample-holding the output of the multiplexer 733, and a signal H for A/D converting the output of the sample-and-hold circuit 734 are output.

ROM shown in Figure 24? 20 is a storage device in which the program shown as a flowchart in FIG. 26 is stored;
M719 is a storage device that temporarily stores intermediate results of arithmetic operations when performing arithmetic processing according to a program. The central processing unit 718 stores the 26th CPU stored in the ROM 720.
According to the program shown in the figure, the instantaneous torque of the entire engine is calculated from the A/D converted data and output to the output device 721.

Next, the operation of the fifth embodiment will be described. The frequency of signals A, A2 corresponding to Schilling internal pressure and signal C for every 1 degree of crank angle is the F/V converter 71 in FIG.
When the crank angular velocity B converted by 4 is input to the A/D converter 71G, and the top dead center signal of the first cylinder is input to the A/D conversion control circuit 736 as shown in FIG. Once every degree, the control signals E, , E7 . E3.
F.

After simultaneous sample and hold by G and H, A/D
converted. These A/D converted data are -
time is stored in the RAM 719 shown in FIG.
Step 1) as shown in Figure 6. Measured Schilling internal pressure P
”: From t+, a pre-specified angle is corrected as the reference pressure, and the corrected Schilling internal pressure p +++,
(Step 2 shown in FIG. 26). Pressure corrected Schilling internal pressure Plit.

is multiplied by the bore cross-sectional area A rea to obtain the force FP' + t) acting on the piston due to the internal pressure of the cylinder (step 3 shown in FIG. 26). Crank semi-arbitrary r Connecting rod length 11 and A/D From the converted crank angular velocity ω, calculate the acceleration α°'' of the piston, further multiply this by the mass Mrec of the reciprocating part, and then calculate the inertia force F of the reciprocating part.
, L (step 4 shown in FIG. 26). The force F p'''ct) acting on the piston due to the cylinder internal pressure P゛°1(t) and the inertia force F1 of the reciprocating part are added together to obtain a resultant force, which contributes to rotationally driving the drive shaft. Multiply the component by the crank radius r to obtain the instantaneous torque T'' for each cylinder (step 5 shown in Figure 26 above). Instantaneous torque T'□' for each cylinder (t) is added for each cylinder, and the instantaneous torque T(t) generated by the entire engine is calculated and outputted to the output device 21 (step 6 shown in FIG. 26).

As described above, in this fifth embodiment, the force acting on the piston due to pressure fluctuations in the cylinder and the inertial force of the reciprocating part are generated on the drive shaft of the piston-type internal combustion engine according to the piston-crank mechanism of the engine. When detecting instantaneous torque, by correcting the reference pressure of pressure fluctuations in the cylinder, the zero drift of the pressure detector due to changes in engine temperature conditions and changes in the reference value are compensated for and the engine is generated with accuracy. Instantaneous torque can be applied. In this fifth embodiment, an A/D converter and a central processing unit J! I! There is an advantage that the reliability of the system is high because it uses a device.

As the rotational speed of the engine increases, the influence of the inertial force of the reciprocating parts increases, and it may not be possible to evaluate the torque generated by the engine using only the Schilling internal pressure. Figure 27 shows the comparison results of torque T3, with the solid line representing the case where the inertial force of the reciprocating part is not considered and the dotted line representing the case where it is taken into account. The instantaneous torque generated on the drive shaft can be suitably evaluated.

"Sixth Example" Next, a sixth example will be described. The sixth example is f
Like the jS5 example, it has a configuration that includes a microprocessor, but does not include the torque generated by the inertial force of the reciprocating part that was handled in the fIS5 example, and is an engine that is generated only by Schilling internal pressure. This is to increase the instantaneous torque of .

FIG. 28 is a block diagram of the sixth embodiment.
\l Excludes Humbertough 14. tlS2
The numbers in Figure 8 are the same as the numbers in Figure 24.

The following is executed by the sixth embodiment. * The operation will be explained according to the flowchart shown in FIG.

When the top dead center signal of the first cylinder is inputted to the A/D conversion unit 716, that is, the A/D conversion control circuit 736 shown in FIG. After each simultaneous sample and hold, A/D
converted. These A/D converted data are temporarily R
The data is stored in the AM 719 (step 1 shown in FIG. 29). From the measured Schilling internal pressure p (-i'J, make a correction using the specified angle as the reference pressure,
Add the corrected Schilling internal pressure P (t) (the above is the second
Step 2) shown in Figure 9). Multiply 2 by the bore cross-sectional area A rea by the pressure-corrected Schilling internal pressure P"1) to find the force F(t) that acts on the re-piston due to the Schilling internal pressure (step 3 shown in Figure 29). Schilling The force Flil that acts on the piston due to internal pressure, the component that contributes to the rotary drive of the drive shaft, and the instantaneous torque for each cylinder is calculated by multiplying by the crank radius r. 2
Step 4) shown in Figure 9). Instantaneous torque T'I for each cylinder
I+t) for each cylinder, and the instantaneous torque T(t) generated by the entire engine is calculated and outputted to the output device 721 (hereinafter referred to as step 5 in FIG. 29).

As described above, in the case of calculating the instantaneous torque acting on the drive shaft only due to fluctuations in the Schilling internal pressure, this sixth embodiment is designed to calculate the instantaneous torque by correcting the Schilling internal pressure. It has the advantage of being simple.

"Seventh Example" Next, a seventh example will be described. The seventh embodiment is also the fifth embodiment.
As in the fifth embodiment, the configuration includes a microprocessor, and in addition to step 6 of the program shown in FIG. 26 of the fifth embodiment, in step 6 shown in FIG. It compensates for torque and torque lost due to friction. A flowchart of the program of this seventh embodiment is shown in FIG. According to the seventh embodiment, the instantaneous torque of the engine calculated from the Schilling internal pressure corrected by the stem 6 and the inertia of the reciprocating part is corrected by the torque consumed by the rocks and friction. It is clear that the instantaneous torque output can be increased. Note that since the correction of auxiliary machinery and friction torque varies depending on the engine and the rotational speed of the engine, the correction constant can be determined using the rotational speed once the engine is determined.

FIG. 31 shows the results of correcting the auxiliary equipment and friction torque according to the seventh embodiment, and the broken lines indicate the torque before correction,
The solid line is the torque after correction, and the dotted line is the wJ5 torque, which is the engine output torque measured using the experimental system shown in the m5 diagram, and the torque after correction and the engine output torque are in good agreement. .

"Effects" As stated above, since the device of the present invention has the above configuration, it has the excellent effect of being able to detect instantaneous torque generated by the internal combustion engine from moment to moment, and is highly reliable. There are many excellent effects such as the structure is jij lj.

[Brief explanation of drawings]

Fig. 1 is a schematic sectional view of an engine for explaining the torque measurement principle of the present invention, Fig. 2 is a block diagram showing the configuration of the device of the present invention, and Fig. 3 is a line showing the zero drift F of the pressure of the pressure detector. Fig. ptS4 is a characteristic diagram showing changes in pressure sensitivity due to temperature, Fig. 5 is a block diagram showing the 6 experimental system for confirming the configuration of the present invention, Fig. 6 is a measurement using the experimental system shown in Fig. 5. A characteristic diagram showing a comparison between the calculated torque and the torque calculated and detected by the device of the present invention! Fig. R7 is a characteristic diagram showing a comparison between the above-mentioned measured torque and the torque detected by the conventional device, and Fig. 8 is a block diagram showing the first embodiment of the present invention. ] I is a graph showing the relationship between the measurement results for establishing the correction relational expression and the torque detected by the device of the present invention, and FIG. The graph shown! Figure 11 is a stroke diagram of a 4-cylinder, 4-cycle engine, and Figure 12 is a block diagram showing the second embodiment of the present invention.
Fig. R13 is a block diagram showing the configuration of the third embodiment, Fig. 14 is a graph showing detection results according to the third embodiment, Fig. 15 is a circuit diagram showing the first embodiment of the present invention, and Fig. 16 is a piezoelectric type. Cross-sectional view showing the state of the pickup being attached to the engine, $
Figure 17 is a timing chart of the output waveform of the crank angle detection circuit, Figure 18 is a timing chart of each output waveform in the torque calculation circuit, Figure 19 is a circuit diagram showing the @2 embodiment, and Figure 20 is the torque correction constant. FIG. 21 is a circuit diagram showing the third embodiment, FIG. 22 is a timing chart of output waveforms of each part, and FIG. 23 is a circuit diagram showing the fourth embodiment. Figure ill'524 is a block diagram showing the fifth embodiment, Figure fIrJ25 is a block diagram showing its main parts, Figure @26 is a flowchart showing the ROM program, and Figure 27 does not take into account the inertia of the reciprocating part. Figure 28 is a block diagram showing the sixth embodiment, Figure 29 is a flowchart showing the program, and Figure 1530 is a flowchart showing the program of the seventh embodiment. FIG. 31 is a graph showing the torque correction results. 1... Pressure detection means, 2... Pressure correction means, 3...
Crank angle detection means, 5... Torque correction means, 6...
- Drive torque calculation means, 9... Inertia torque calculation means. Figure 1? , 2 Figure 10 Figure 11 Figure 11-A ((' ) (deg) (a) Figure 14 (b) Figure 29 Figure 30

Claims (4)

[Claims] (1) In an internal combustion engine, a pressure detection means for detecting pressure fluctuations in the shilling and a reference value for the shilling internal pressure are set,
A pressure correction means corrects the output of the pressure detection means based on the reference value, a crank angle detection means detects the crank angle of the engine, and calculation is performed using the output of the pressure correction means and the output from the crank angle detection means. 1. A torque detection device for an internal engine, comprising: a torque calculating means for converting the torque into torque generated by the engine and outputting a signal corresponding to the torque of the engine. (2) Torque correction means is provided which is connected to the torque calculation means and outputs a signal corresponding to the engine output torque obtained by subtracting auxiliary drive torque and friction torque from the output corresponding to the torque generated by the engine. A torque detection device for an internal combustion engine according to claim (1). (3) The above-mentioned torque calculation means includes a drive torque detection means that calculates and outputs a component corresponding to the drive torque from the torque generated by the engine by specifying a crank angle. The torque detection device for an internal combustion engine according to item (1). (4) Determine the crank angular velocity from the output of the crank angle detection means, calculate and output the inertia force due to the mass of the reciprocating part from the piston acceleration determined by the crank angular velocity, crank radius, and connecting rod length, and the mass of the reciprocating part. Claim 1, further comprising an inertial force calculating means for calculating the inertial force, and adding the output of the inertial force calculating means and the output of the pressure correcting means and converting the result into torque generated by the engine. Torque detection device for internal combustion engines.