JPH02212222A - Engine suspension device - Google Patents

Abstract

PURPOSE:To improve controllability by reading an engine-torque interrelation value from a two dimensional map for engine rpm and throttle opening and, based on that value, controlling active control mounts capable of control variably spring characteristics and/or damping characteristics. CONSTITUTION:An engine 1 is suspended from a body, for example, on its both sides, through active control mounts 2 capable of control variably spring characteristics and/or damping characteristics. The mounts 2 are operated and controlled by an ECU 3 in which an engine rpm signal 4 and throttle opening signal 5 are transmitted. In this case, a value having interrelation to an engine to an engine torque is memorized in a two dimensional map for the engine rpm NE and throttle opening TA stored in the ECU. Based on the present NE and TA values, a torque to be generated in stationary operation or a value having interrelation to it is retrieved, and the mounts 2 are controlled according to that retrieved result.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an engine suspension system having an active control mount, and particularly to a device that optimizes characteristic switching control of the active control mount.

Note that the active control mount in this specification refers to an engine mount whose spring characteristics and/or damping characteristics can be variably controlled, as well as an absorber or mount provided in an engine suspension system whose spring characteristics and/or damping characteristics can be variably controlled. This is a broad concept that includes roll control stops and the like.

[Prior Art] In an engine suspension system, a mechanism is known that actively controls the spring characteristics and/or damping characteristics of the engine support means to reduce engine vibration and rolling. The purpose of changing the characteristics of the active control mount is mainly to make the damping and spring characteristics harder during high-load, high-speed driving, etc.
and ■improving drivability by regulating engine movement during sudden acceleration and deceleration. As a technology related to the above (1), Japanese Patent Laid-Open No. 62-216822 discloses a method that changes the characteristics of the active control mount according to the intake pipe pressure, making it soft in the idle region, normal in the steady region, and high. A hard control method is disclosed in the load area. In addition, as a technique related to the above (■), the Japan Institute of Invention and Innovation Publication Technical Bulletin No. 88-5644 describes the relationship between intake pipe pressure (PM) and change in intake pipe pressure (ΔPM).
A method is disclosed in which characteristics of an active control mount are controlled based on values read from a dimensional map. Furthermore, the change in throttle opening (ΔTA
) is also known in which the characteristics of the active control mount are switched by pressing a trigger.

[Problems to be Solved by the Invention] However, the control of the active control mount based on the intake pipe pressure has the following problems.

In other words, as shown in Fig. 8, the throttle is opened 1! (T
There is a time delay in the change in intake pipe pressure (PM) that actually occurs with respect to the change in A), so controlling the active control 71 by determining the intake pipe pressure and its change does not take much time to control. There will be a delay. During sudden acceleration/deceleration, etc., it is desirable to accurately predict the sudden change in engine torque, engine vibration, or movement that is about to occur, and harden the active control mount to reduce the amount of engine movement. Due to the delay, it is difficult to accurately switch characteristics before large vibrations or movements actually occur.

In this regard, if the change in throttle opening (ΔTA) is used as a trigger for sudden acceleration or deceleration, the problem of control time delay can be solved.

However, with active control mounts whose main purpose is to achieve the above-mentioned effect (■), throttle opening changes (ΔTA
), if the trigger level of Δl A is adjusted (becomes large) on the high engine speed side, the trigger will not be activated on the low engine speed side, and △ on the low engine speed side.
When the TA trigger level is adjusted (reduced), the trigger is applied too much on the high rotational speed side, and there is a problem that desired drivability and imaging noise characteristics cannot be obtained, respectively. The reason for this will be explained using FIGS. 9 and 10.

FIG. 9 shows the throttle opening degree arranged according to engine speed and intake pipe pressure. As you can see from this figure,
For example, at 5000 rpm, the throttle opening must be 40 degrees in order for the intake pipe pressure to reach approximately atmospheric pressure. However, at 11,000 rpm, the pressure becomes approximately atmospheric when the opening degree is 10 degrees. This is 5000rpm and 11000rpm
This is because the amount of intake air differs by a factor of 5 between the two, so the required throttle opening (aperture) also differs when the intake pipe pressure is the same. Therefore, at low engine speeds, a large engine torque can be produced even if the throttle is slightly opened. For example, as shown in Fig.
A) and throttle opening change (△-1-A: to degree)
Even if the torque (-I R
Q ) differs greatly, and the amount of engine movement that occurs at that time, for example, the rolling m, also differs greatly. In the first place, Δ
- [The reason why the i-regulator is applied at A is that the engine torque changes after that due to the change in throttle opening (△TRQ>
In anticipation of this, when engine torque suddenly changes, the engine mount is made harder to reduce the amount of engine movement, improving drivability and preventing the engine from interfering with the engine compartment. To do this, it is necessary to accurately predict ΔTRQ, but for the reasons shown in Figures 9 and 10 above, even if ΔTA is -8TA, the change in intake pipe pressure at that time Since the magnitude of ΔTRQ varies depending on the engine speed, it is difficult to accurately predict ΔTRQ, and therefore the control objective described above cannot be achieved.

The present invention focuses on these problems in the conventional technology, accurately predicts engine torque changes that will actually occur in advance, accurately controls the active control mount to desired characteristics, and maintains the entire operation. The purpose is to control excessive engine movement and improve drivability in this area.

[Means for Solving the Problems] An engine suspension system of the present invention in accordance with this object is an engine suspension system having an active control mount that can variably control spring characteristics and/or damping characteristics.
A two-dimensional map of engine speed and throttle opening is provided in the control system of the active control mount, and a value that has a correlation with the engine torque is added to the active control mount based on the two-dimensional map. It consists of things stored in order to control.

The values that correlate with the engine torque are as follows:
It may be the intake pipe pressure, the actual torque, or a dimensionless value. In short, it is sufficient if there is a correlation with the engine torque.

[Function] In such an engine suspension system, the correlation value itself with engine torque in a steady state, which is read from a two-dimensional map of engine speed and throttle opening,
Alternatively, the characteristics of the optimal active control mount desired thereafter are determined from the change, and the control is performed according to the characteristics. Therefore, for example, by applying a trigger to the change in the above value, that is, the change in engine torque, the acceleration control mount can accurately predict the engine movement that is about to occur and set the optimum acceleration control mount for that movement. It becomes possible to control the characteristics in advance. It is a two-dimensional map of engine speed and throttle opening, and since it includes the factor of throttle opening, there is no problem of control time delay, and it is able to handle sudden engine movements that may actually occur. Therefore, it is possible to perform control in advance with sufficient time margin for switching the active control mount characteristics. Further, since the determination is made using the correlation value of the engine torque, it is possible to accurately predict the engine movement that will occur regardless of the engine speed at that time. In advance, accurately and with sufficient time, install the active control mount's special forward side a (
By performing this switching, sudden movement of the engine is suppressed and drivability is improved.

In addition, since the engine torque correlation value is read from a two-dimensional map of engine speed and throttle opening, all factors of engine speed, throttle opening, and engine torque at that time can be grasped simultaneously to determine the engine operating state. By appropriately setting the characteristics recorded in the map, the torque correlation value itself can be grasped uniquely and accurately, even in steady operating conditions or operating conditions with little change. , making it possible to control any desired active control mount characteristics.

[Embodiments] Preferred embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show an engine suspension system and its control characteristics according to an embodiment of the present invention. Figure 1 shows the overall general configuration of this engine suspension system.
indicates the engine mounted on the vehicle. The engine 1 is suspended on the body side, for example, on both sides thereof via active control mounts (engine mounts) 2 that can variably control a spring constant, a damping coefficient, or both. From the engine 1 side, an engine speed signal 4 (NE) and a throttle opening signal @5 (TA) are sent to the ECU 3 as a controller, and the ECU 3 sends a signal 6 to the active control mount 2 to control its operating state. Kudzu sent.

In the ECU 3, search, calculation, and determination processing are performed according to the flow shown in FIG.

The flow shown in FIG. 2 is executed, for example, every 16 TrLsec. First, in step 101, the engine speed NE and throttle opening TΔ at that time are read out. In step 102, the engine speed NE
Values having a correlation with the engine torque are stored in the two-dimensional map 7 of the engine torque and the throttle opening TA, and the table is searched for the torque produced during steady operation at the current NE and TA, or a value correlated thereto. -r Read as RQ.

For example, as shown in FIG. 3, this TRQ map 7 is a two-dimensional map of engine speed NE and throttle opening TA, with intake pipe pressure PM that substantially corresponds to engine torque as contour lines. It consists of things that have been memorized. In addition to the above-mentioned intake pipe pressure, the value having a phase relationship with the engine torque may be the actual torque itself, or may be a dimensionless value. In other words, it is sufficient if there is a correlation with the engine torque.

Next, in step 103 in Figure 2, the previous and current -
The rRQ difference Δ1-RQ is determined. This Δ1゛RQ
indicates the torque change, that is, the differential phase value of the torque. Then, in step 104, the current TRQ is stored for the next calculation. Step 105
In , a trigger is applied to the above ΔTRQ,
When the magnitude of ΔTRQ is larger than a certain value (A>), the active control mount is set to hard mode in step 106, and when it is smaller, it is set to soft mode. This mode switching from hard to soft requires an appropriate time delay. You may also have

In this embodiment, the value A is a fixed value, but it may be a variable value depending on the parameters representing the operating conditions of the vehicle and engine. Further, the value may be changed during acceleration and deceleration. Furthermore, regarding map 7 in step 102, even if you want to make the torque hard, for example, you may want to make it soft intentionally due to drivability requirements. It is also possible to change only the value of the map.

Regarding the above-mentioned embodiment, the operation and effect of the control will be explained with reference to FIGS. 4 and 5.

FIG. 4 shows an example during acceleration, and shows a state where the throttle opening degree TA has been changed twice in the opening direction. The engine speed NE gradually increases and the vehicle is accelerated. At this time, intake pipe pressure PM and torque TRQ
This will be explained by comparing the case where the active control mount is controlled with ΔTA (conventional control) and the case where it is controlled with Δ-rRQ (control of the present invention). In ΔTA control, the active control mount is made hard during the second acceleration, but in reality, during the first acceleration, ΔTA is smaller but the engine speed is lower, so the PM is lower.
(“;TRQ> has a strong rise. Δ−r RQ
In Ill III, since ΔTRQ is larger during the first acceleration, the active control mount is switched to hard during the first acceleration.

As a result, when comparing engine movement in terms of rolling amount, ∆TA control causes large fluctuations during the first acceleration, whereas ∆T RQ control suppresses engine movement by making the active control mount harder. , these fluctuations are successfully suppressed and attenuated, improving drivability. During the second acceleration,
Since ΔTRQ is originally small, ΔTA control and Δ-rR
There is no substantial difference between Q control and Q control. Overall, ΔT RQ control suppresses engine movement to a much smaller extent and improves drivability.

In the above control, it is necessary to accurately predict the rise in torque as described above with sufficient time margin before the engine movement that will occur actually occurs. Regarding this point, the forced test results shown in FIG. 5 compare the conventional △TA control and the case where the intake pipe pressure PM is read from the two-dimensional map of NE and -A according to the present invention and is controlled based on that value. Explain with reference to.

In Fig. 5, PMTA corresponds to the maximum readout from the two-dimensional map, and ΔPMTA is the change (differential value).
It shows. TA is the throttle opening, ΔTA is the change thereof, and PM is the intake pipe pressure. Characteristic C is the degree of rolling of the engine when the active control mount is not controlled, and characteristic C is the degree of engine rolling measured by the acceleration sensor when the active control mount is not controlled. It shows the amount equivalent to force. When the throttle opening degree TA is gradually increased, the intake pipe pressure PM rises after a certain time delay, and then a large rolling occurs in the engine, a large impact force is applied, and the engine moves significantly. As mentioned above, if you simply measure the change in PM, there is not much time between its detection and the actual engine operation.
Active control mount control is delayed.

△TA control can solve this time delay problem to some extent, but as the peak does not appear as shown in the figure, it is difficult to apply an effective trigger, which means that sudden changes in engine torque (engine movement) may occur. It is difficult to predict accurately.

In the ΔP MTA control, since the component of Δ-1-A is included, the problem of control time delay is solved, and a peak sufficient for triggering can be obtained. The time between this peak and the engine movement that would occur is, in this example, −[A
There was almost no change in the rate of change in engine speed NE, which was approximately 130 to 170 m5ec. This time is usually sufficient to effect the desired switching of the active control mount. Therefore, △P M T
A 1Ill l ensures that the desired active controller 1-Lj-le mount control is performed 1q.

Next, another control example of the present invention is shown in FIG.

The flow shown in FIG. 6 removes steps 103 and 104 from the flow shown in FIG. The mounting is switched to hard or soft (step 206).

In this way, it is possible to read out the TRQ itself according to the engine or vehicle operating condition, not only during acceleration/deceleration, etc., but also in steady or near steady engine operating conditions, and based on that, active control mount control can be performed to any characteristic. It is. Further, the controls shown in FIGS. 2 and 6 can also be combined.

Furthermore, depending on the active control mount, it is possible to switch not only to two stages (soft and hard), but also to several more stages. .206, it is possible to compare ΔT RQ or TRQ with values in several stages and control the active control mount in several stages based on the comparison.

Further, in the above embodiment, the active control mount is applied to the engine mount, but the active control mount in the present invention includes all means that can variably control the support characteristics provided in the engine suspension system. For example, as shown in FIG. 7, an engine suspension system in which a variable absorber 13 is provided on the side of the engine 11 and can variably control the spring constant and/or damping coefficient in the rolling direction of the engine 11 with respect to the body side 12 may also be used. The present invention is applicable.

[Effects of the Invention] As explained above, when using the engine suspension system of the present invention, the engine torque correlation value is read from the two-dimensional map of the engine speed and the throttle opening, and the acceleration control mount is controlled based on the correlation value. As a result, it is possible to predict the engine movement that will occur with sufficient time for control, and by this prediction,
Regardless of the engine speed, the active control mount can be accurately and reliably controlled to desired characteristics, reducing engine movement and vibration, and improving drivability.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an engine suspension system according to an embodiment of the present invention, FIG. 2 is a control flow diagram of the device in FIG. 1, and FIG. 3
Figure 4 shows the characteristics of each factor when controlling according to the flow shown in Figure 2. Figure 5 shows the case when the throttle opening is changed. Fig. 6 is a control flow diagram showing a control example different from Fig. 2 according to the present invention; Fig. 7 is a schematic configuration diagram of an engine suspension system according to another embodiment of the present invention. , Figure 8 is a characteristic diagram of throttle opening and intake pipe pressure on the same time axis, Figure 9 is a diagram of the relationship between engine speed, intake pipe pressure, and throttle opening, and Figure 10 is a diagram of throttle opening and engine This is a diagram showing the relationship between torque and engine rolling. 1.11... Engine 2... Active control mount 3... ECU 7... ...2D map 13...
......Variable absorber as active control mount Fig. 2 Fig. 5 Fig. 6 Fig. 8 A l06 Time

Claims (1)

[Claims] (1) In an engine suspension system having an active control mount that can variably control spring characteristics and/or damping characteristics, a two-dimensional map of engine rotation speed and throttle opening is provided in the control system of the active control mount. An engine suspension system characterized in that a value having a correlation with engine torque is stored in a two-dimensional map in order to control an active control mount based on the value.