JP3965996B2 - Vehicle control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle control apparatus, and more particularly, to a vehicle control system having a mechanism for automatically executing a shift operation of a transmission and an intermittent operation of a clutch in response to a manual operation for selecting a gear position of the transmission. Relates to the device.
[0002]
[Prior art]
Conventionally, as a mechanism for automatically executing the shift operation of the transmission and the engagement / disengagement operation of the clutch in accordance with the selection operation of the shift stage as described above, a sequential manual transmission (hereinafter referred to as “SMT”) is known. A semi-automatic transmission mechanism known as “Semiconductor” is known.
[0003]
As an example of a series of control operations by the SMT, when a shift lever is operated to change the transmission gear stage, the clutch is first disengaged and the gear is switched to a predetermined gear stage. An operation of gradually engaging the clutch is performed, and in parallel with this operation, a process of controlling the engine speed to a suitable speed by adjusting the engine output to reduce the shift shock is also executed.
[0004]
[Problems to be solved by the invention]
On the other hand, the traction control (TRC) that improves the driving stability by suppressing the tendency of the drive wheels to slip when starting or accelerating, and the vehicle's turning behavior is stabilized by suppressing the spin tendency and drift-out tendency during turning. Even a vehicle travel control system such as vehicle stability control (VSC) to be controlled is accompanied by control for adjusting engine output.
[0005]
As described above, in SMT, when the shift lever is operated, a series of shift control including adjustment control of the engine output is started. For example, the driver operates the shift lever during execution of the traction control. In such a case, adjustment control of the engine output is included in both control systems. Therefore, when the engine output is adjusted based on one control command value, the controllability of the other control system may be reduced. .
[0006]
The present invention has been made to solve such problems, and the object of the present invention is to request a change in engine output from both the vehicle travel control system such as TRC control and VSC control and the SMT control system. In such a case, it is an object of the present invention to provide a vehicle control device capable of suitably coordinating both control systems.
[0007]
[Means for Solving the Problems]
Therefore, a vehicle control apparatus according to claim 1 is provided with a mechanism that automatically executes a shift operation of the transmission and an intermittent operation of the clutch in response to a manual operation for selecting a gear position of the transmission. And a clutch mechanism having a clutch that changes the transmission state of the engine rotation output when the engagement state changes, and a first actuator that serves as a drive source that changes the engagement state of the clutch And a second actuator serving as a drive source for switching the meshing state of the gear trains that constitute each of the gears, and a plurality of gears that change the rotational output of the engine transmitted via the clutch mechanism. The operation control of the first actuator and the second actuator is performed in accordance with the manual operation for setting the speed change mechanism and the speed change stage of the transmission, and the shift of the speed change stage is performed. Given from the SMT control unit for requesting a change in engine output in accordance with the state and the intermittent change of the clutch, a travel control unit for performing a travel control of the vehicle with a request for a change in engine output, and the SMT control unit and the travel control unit An engine output control unit that receives the engine output change request and controls the engine output, and the engine output control unit receives the change request of the engine output given from the SMT control unit and the travel control unit. The change request of the SMT control unit is preferentially selected according to the combination of the increase / decrease of the duplicate change request, and the case where the priority selection is canceled. The engine output is controlled based on one of the change requests according to
[0008]
As described above, the control process by the SMT control unit is a series of control processes for shifting the shift stage of the transmission mechanism unit from the current shift stage to another shift stage until the shift stage transition process is completed. In principle, it is not preferable to change or interrupt the control. Therefore, in principle, the engine output control unit preferentially selects the change request of the SMT control unit even when the engine output change requests given from the SMT control unit and the travel control unit are duplicated.
[0009]
On the other hand, depending on the combined form of increase / decrease of the engine output change request that overlaps in this manner, it is better to cancel the priority selection for the change request of the SMT control unit in order to better coordinate the SMT control and the traveling control. A more preferable case may also occur. Therefore, when such overlapping engine output change requests are in a specific combination, the engine output control unit cancels the priority selection for the change request of the SMT control unit, and suitably coordinates SMT control and traveling control. The engine output change request that can be selected is selected.
[0010]
According to a second aspect of the present invention, there is provided a vehicle control device according to the first aspect, wherein the engine output control unit is selected preferentially when both the SMT control unit and the travel control unit request reduction of the engine output. Is selected, and a change request with a smaller engine output is selected from among the change request of the SMT control unit and the change request of the travel control unit.
[0011]
As described above, a situation in which both the SMT control unit and the travel control unit request a reduction in engine output is assumed, for example, a situation in which an upshift operation of a transmission is performed during acceleration. As a premise for the above, there is a case where the engine speed during acceleration is higher than the driver's feeling. It can also be assumed that the driver determines that the road surface μ has decreased. Under such circumstances, the engine output control unit determines that it is preferable to control the engine output in a direction that does not require rapid acceleration and makes the acceleration gain duller. Of the change requests from the control unit, the change request with the smaller engine output is selected.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0013]
FIG. 1 schematically shows the configuration of a vehicle control apparatus according to an embodiment. This vehicle is equipped with an SMT (sequential manual transmission) that automatically executes the shift operation of the transmission and the engagement / disengagement operation of the clutch in response to the selection operation of the shift stage.
[0014]
Reference numeral 10 indicates an operation position of the shift lever, and an N (neutral) position and an R (reverse) position are provided along the longitudinal direction of the vehicle body. To move from the N position to the S position, and operate the "+" side, which is the forward direction of the driver, to perform an upshift operation of the transmission, and operate the transmission to the "-" side, which is the opposite direction. Downshift operation.
[0015]
In addition, when the shift lever is operated to the “+” side and the “−” side, the mechanism returns to the neutral S position when the driver removes the hand from the shift lever. Further, upshifting means that the gear stage is switched so that the transmission gear ratio (reduction ratio = rotation amount of the input shaft of the transmission / rotation amount of the output shaft of the transmission) becomes a smaller value. Downshift means that the gear position is switched so that the gear ratio becomes a larger value.
[0016]
Such shift lever operation information is given to the SMT control unit 20, and the SMT control unit 20 uses the shift lever operation information, the wheel speed as the rotational speed of the drive wheel 64, etc. Operation control of the transmission mechanism unit 40 is performed.
[0017]
The clutch mechanism unit 30 constitutes a so-called automatic clutch, and includes a friction clutch and a drive motor (first actuator) that changes the engagement state of the friction clutch. It is a mechanism that changes the contact / separation state of the friction clutch by rotationally driving. The speed change mechanism unit 40 includes a reverse gear stage and a plurality of forward gear stages, and a gear shift actuator (second actuator), and a mechanism for switching the meshing state of each gear mechanism by driving the gear shift actuator. It has become.
[0018]
Accordingly, the rotational output of the engine 50 is transmitted to the propeller shaft 60 via the clutch mechanism 30 and the speed change mechanism 40, and the rotation of the propeller shaft 60 is transmitted to the left and right drive wheels 64 via the differential 62.
[0019]
Further, in such a series of gear change control, the difference in the rotational speed between the output shaft 52 of the engine 50 and the input shaft (not shown) of the speed change mechanism section 40 is preferable within the clutch mechanism 30 as a boundary. The engine output adjustment control is also performed at the same time. For this reason, the SMT control unit 20 requires an engine output request value that is suitable for engine output in terms of SMT control with respect to the engine control unit 70 that controls engine output during this shift (gear change) control. Is output.
[0020]
The engine control unit 70 is given an operation amount of an accelerator pedal 80 detected by an accelerator pedal sensor 82, an engine speed detected by an engine speed sensor (not shown), and the like. The engine output required by the driver is required.
[0021]
A traction control (TRC) system that suppresses acceleration slip is also mounted, and the TRC control unit 90 executes control processing. The TRC control unit 90 provides a hydraulic pressure instruction value to the brake actuator 100 that controls the brake pressure of the brake device 66 at each wheel based on the difference in wheel rotation speed between the drive wheel 64 and the driven wheel (not shown). Output. At the same time, a required engine output value is obtained so as to obtain a suitable engine output for traction control control, and is output to the engine control unit 70.
[0022]
Therefore, the engine control unit 70 includes a request value for the engine output from the SMT control unit 20 in addition to the request value for the engine output based on the operation of the accelerator pedal 80, and the TRC control unit. An engine output request value from 90 is also given, and the engine control unit 70 selects any one request value. Then, an opening instruction value of the throttle valve 110 corresponding to the selected required engine output value is output to the throttle drive unit 112.
[0023]
Here, the engine output request value selection process performed by the engine control unit 70 will be described with reference to the flowchart of FIG. This flowchart is activated by turning on the ignition switch.
[0024]
First, the process proceeds to step 102 (hereinafter, “step” will be referred to as “S”), and the required value of the engine output requested by the driver is calculated based on the operation amount of the accelerator pedal 80 and the engine speed. For example, the required value of the engine output corresponding to the operation amount of the accelerator pedal 80 and the engine speed is previously mapped, and the map is searched based on the operation amount of the accelerator pedal 80 and the engine speed, Sets the required engine output value requested by the driver.
[0025]
In the subsequent S104, it is determined whether the SMT control is being performed. If “No”, the process proceeds to S106 to determine whether the TRC control is being performed. If “No” is determined in S106, the process proceeds to S108, and the engine output request value requested by the driver (hereinafter abbreviated as “driver request value”) calculated in S102 is used as an engine output request. Set as a value. Thereafter, the process proceeds to S110, and the opening instruction value of the throttle valve 110 corresponding to the engine output request value is output to the throttle drive unit 112.
[0026]
Therefore, when the SMT control accompanying the gear change is not started and the TRC control as the vehicle running control is not started, the opening degree of the throttle valve 110 is controlled according to the accelerator operation of the driver. Therefore, engine output in accordance with the driver's request is generated.
[0027]
If TRC control is started under the condition “Yes” in S106, that is, SMT control associated with gear change is not started, the process proceeds to S126, and is given from the TRC control unit 90 as described above. The engine output request value (hereinafter abbreviated as “TRC request value”) is read. Then, the process proceeds to S128, where the TRC request value is set as the engine output request value. Then, the process proceeds to S110, and the opening instruction value of the throttle valve 110 corresponding to the engine output request value is output to the throttle drive unit 112.
[0028]
When the TRC control is started in a situation where the gear change is not performed as described above, the engine control unit 70 opens the throttle valve 110 based on the required engine output value given from the TRC control unit 90. Control the degree.
[0029]
On the other hand, if “Yes” in S104, that is, if the SMT control associated with the gear change is started, the process proceeds to S112, and the engine output request value (hereinafter referred to as “SMT”) given from the SMT control unit 20 as described above. Abbreviated as “required value”). In subsequent S114, it is determined whether the SMT request value is larger than the driver request value calculated in S102. In S114, if “Yes”, that is, if the SMT request value is greater than the driver request value, the process proceeds to S116. In order to suppress the shift shock, the SMT request value read in S112 is set as the engine output request value.
[0030]
Here, the shift shock will be described. Assuming that the engine 50 side is an input element and the speed change mechanism section 40 side is a reaction force element with the clutch mechanism section 30 as a boundary, a series of gear change operations includes the engagement / disconnection of the input element and the reaction force element, and the reaction force element. The torque acting on the output shaft 52 of the engine 50 due to the change in the torque shared between the elements and the influence of the inertial force of the rotating member, etc. when changing gears, because it is performed by switching the gear train constituting the gear train. May fluctuate. When this torque fluctuation occurs, when the occupant senses a change in vehicle acceleration caused by this torque fluctuation, this is called a shift shock.
[0031]
Accordingly, in S116, in order to reduce this shift shock when the clutch is engaged again after the shift stage of the transmission mechanism 40 is switched, the output shaft 52 of the engine 50 and the input shaft (see FIG. It is necessary to suppress the difference in rotational speed with a predetermined range within a predetermined range, and it is preferable that the engine 50 has a higher engine output by determining that the rotational speed of the engine 50 is low and the shift shock becomes large according to the driver request value. The SMT request value for which the correct engine output is set is selected.
[0032]
Then, in order to proceed to S110 described above, an opening degree instruction value of the throttle valve 110 corresponding to the SMT request value is output to the throttle drive unit 112.
[0033]
On the other hand, if “No” is determined in the previous S114, that is, if the driver request value is larger than the SMT request value, the process proceeds to S118 to determine whether TRC control is being performed. If “No”, the process proceeds to S120, the driver request value is set to the engine output request value, and then the process proceeds to S110. Therefore, the opening instruction value of the throttle valve 110 according to the driver request value calculated in S102. Is output to the throttle drive unit 112.
[0034]
As described above, the situation in which the process proceeds to S120 is assumed, for example, when the driver is stepping on the accelerator pedal 80 and requesting rapid acceleration, and in such a case, the driver's sudden acceleration is reduced rather than the shift shock being reduced. The engine output according to the driver's request is generated in response to the acceleration request. Therefore, in such a situation, the driver gets a driving feeling close to that of the manual transmission.
[0035]
On the other hand, if “Yes” in S118, that is, if TRC control is being performed (SMT control is also being executed), the process proceeds to S122, and the above-described TRC request value is read. In step S124, the SMT request value read in step S112 is compared with the TRC request value read in step S122, and the request value having the smaller engine output is set as the engine output request value. Proceed to Note that “MIN (SMT request value, TRC request value)” shown in FIG. 2 means that a request value having a smaller engine output is selected from the SMT request value and the TRC request value.
[0036]
By executing such control processing, for example, when the driver changes gears during TRC control, both the SMT request value and the TRC request value are given to the engine control unit 70. In this case, the process proceeds to either S116 or S124 in the flowchart of FIG. 2, and the SMT request value or the TRC request value is set as the engine output request value.
[0037]
Therefore, when the SMT request value and the TRC request value overlap as the engine output request value, four combinations can be generated as shown in FIG. Then, according to the combination pattern of the output request, a combination pattern for preferentially selecting the request of the SMT control unit 20 and setting the SMT request value as the engine output request value (when proceeding to S116), and such an SMT When the priority selection is canceled as described above, it is roughly divided into a combination pattern for canceling the priority selection of the request value (when proceeding to S124). As described above, the engine output is higher among the SMT request value and the TRC request value. The smaller required value is selected as the engine output required value.
[0038]
As a TRC request value, an increase request, i.e., a request to increase the engine output, is assumed, for example, when the vehicle is decelerating, and a TRC request value is a decrease request, i.e., a request to reduce the engine output. For example, it is assumed that the vehicle is accelerating. In addition, the case where the increase request is issued as the SMT request value is assumed, for example, when the driver performs a downshift operation, and the case where the decrease request is issued as the SMT request value, for example, a case where the driver performs an upshift operation is assumed. Is done.
[0039]
Therefore, the combination of output requests indicated by (a) in FIG. 3 is a case where there is a request for increasing the engine output from both the TRC control unit 90 and the SMT control unit 20, and the combination of output requests indicated by (b) in FIG. Is a case where there is a request for increasing engine output from the TRC control unit 90 and a request for decreasing engine output from the SMT control unit 20. As described above, when there is an increase request as the TRC request value, it can be considered that the vehicle is in a decelerating state and the rotational speed difference between the driving wheel and the driven wheel exceeds a predetermined range. Assuming that the SMT control unit 20 executes a series of gear change operation control under such a situation, a control process for disconnecting the clutch is performed in the middle of the shift operation. Transmission of engine output to the wheel 64 is interrupted, and as a result, the rotational speed difference between the driving wheel and the driven wheel is reduced. This is a preferable result from the viewpoint of TRC control that suppresses the slip tendency of the wheels.
[0040]
Therefore, in the case of the combination of output requests shown in FIGS. 3A and 3B, the SMT request value is preferentially selected as the engine output request value, and thereby a series of gear change operations. The control is suitably executed, the wheel slip tendency is also suppressed, and the SMT control and the TRC control can be suitably coordinated.
[0041]
Also, the combination of output requests indicated by (c) in FIG. 3 is a case where there is a request for reducing engine output from the TRC control unit 90 and a request for increasing engine output from the SMT control unit 20. Since the TRC request value is a decrease request, the vehicle is in an accelerated state, and since the SMT request value is an increase request, it can be considered that the driver performs a downshift operation. In such a situation where a downshift operation is performed during acceleration, it is determined that the driver is requesting rapid acceleration. In such a case, the engine rotation is quickly performed to meet the driver's rapid acceleration request. The SMT control is prioritized and executed so that the number of the gears is adjusted to suppress the shift shock and the clutch is suitably connected in a short time. As a result, the shift time (idle running time) is minimized and the gear change is completed in a short time, and immediately after the completion, slip suppression control by the TRC control unit 90 is started. Thus, the driver's acceleration request is satisfied and the delay time or start timing delay of the TRC control unit 90 is minimized, so that SMT control and TRC control can be suitably coordinated.
[0042]
Also, the combination of output requests indicated by (d) in FIG. 3 is a case where both the TRC control unit 90 and the SMT control unit 20 have a request to reduce engine output. Since the TRC request value is a reduction request, for example, an acceleration state of the vehicle is assumed, and since the SMT request value is a reduction request, it can be considered that the driver has performed an upshift operation. By performing an upshift operation during acceleration, an increase in engine speed can be suppressed, so that it can be determined that the driver does not require rapid acceleration. For example, it is assumed that the upshift operation is performed when the driver's judgment is applied such as when the road surface μ feels lowered during acceleration or the engine speed is high and an acceleration slip occurs after shifting. it can. In such a situation, the priority selection of the SMT request value is canceled according to the control idea that the slip suppression control of the wheel can be achieved more reliably, and the engine output is reduced between the SMT request value and the TRC request value. The smaller required value is selected as the engine output required value.
[0043]
In the embodiment described above, the TRC control is shown as the traveling control of the vehicle accompanied by the change request of the engine output. However, the present invention is not limited to this example. For example, the vehicle suppresses the spin tendency and the drift-out tendency when turning. Even vehicle stability control (VSC), which stabilizes the turning behavior of the vehicle, is accompanied by a demand for changes in engine output. Therefore, by replacing “TRC” with “VSC” in the flowchart of FIG. 2 and the like, it can be applied to VSC control as it is.
[0044]
In the embodiment described above, for example, FIG. 3 and the like have been described as requests for increasing / decreasing the request values of SMT and TRC, but requests for increasing / decreasing the engine output are requests for opening / closing the throttle valve 110. In order to respond to the request, it can be handled as a request for opening / closing the throttle valve instead of a request for increasing / decreasing the engine output.
[0045]
【The invention's effect】
As described above, when the engine output change requests given from the SMT control unit and the travel control unit are duplicated, the vehicle control device according to each claim determines whether the SMT is in accordance with the combination of increase / decrease of the change request. A configuration including an engine output control unit having a case where a change request of the control unit is preferentially selected and a case where the priority selection is canceled is adopted.
[0046]
Thus, in principle, priority is given to the engine output change request given from the SMT control unit in order to cope with the SMT control in which a series of shift operations need to be performed in response to an instruction from the driver. Can do. Moreover, in the case of a specific combination in which cooperation between SMT control and travel control is further improved by temporarily canceling the priority selection for the change request of the SMT control unit, priority regarding the change request of the SMT control unit By canceling the selection and adopting a method of selecting one change request from another point of view, it is possible to better coordinate SMT control and travel control.
[Brief description of the drawings]
FIG. 1 is a block diagram schematically showing a power transmission system and a control system of a vehicle according to an embodiment.
FIG. 2 is a flowchart showing a control process performed by an engine control unit.
FIG. 3 is a chart showing combinations of increase / decrease requests when the SMT request value and the TRC request value overlap.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Each operation position of a shift lever, 20 ... SMT control part 30 ... Clutch mechanism part, 40 ... Transmission mechanism part, 50 ... Engine 70 ... Engine control part, 80 ... Accelerator pedal, 90 ... TRC control part 100 ... Brake actuator, 110 ... Throttle valve

Claims (2)

A vehicle control device including a mechanism for automatically executing a shift operation of the transmission and an intermittent operation of a clutch in response to a manual operation for selecting a gear position of the transmission,
A clutch mechanism having a clutch that changes the transmission state of the rotational output of the engine by changing the engagement state, and a first actuator that serves as a drive source that changes the engagement state of the clutch;
A speed change mechanism having a plurality of shift speeds for shifting the rotational output of the engine transmitted through the clutch mechanism, and a second actuator serving as a drive source for switching the meshing state of the gear trains constituting the respective speed speeds And
The operation control of the first actuator and the second actuator is performed in accordance with a manual operation for setting the shift stage of the transmission, and the engine output change request is made in accordance with the shift state of the shift stage and the intermittent change of the clutch. An SMT controller;
A traveling control unit that performs traveling control of the vehicle with a request for change in engine output;
Receiving an engine output change request given from the SMT controller and the travel controller, and an engine output controller for controlling the engine output,
When the engine output change request given from the SMT control unit and the travel control unit is duplicated, the engine output control unit changes the SMT control unit according to the combination of increase / decrease of the duplicate change request. Control of a vehicle which has a case where a request is preferentially selected and a case where this priority selection is canceled, and which controls the engine output based on one of the change requests according to a combination of each change request apparatus. The engine output control unit
When both the SMT control unit and the travel control unit request reduction of engine output, the priority selection is canceled, and the engine change request among the change request of the SMT control unit and the change request of the travel control unit is 2. The vehicle control device according to claim 1, wherein a change request with a smaller output is selected.

Images