JPH0712794B2 - Vehicle constant-speed traveling device - Google Patents

Description

Description: [Industrial field of application] The present invention relates to a vehicle constant speed traveling device for traveling a vehicle at a desired set speed.

[Prior Art] This type of vehicle constant-speed traveling device performs constant-speed traveling control by comparing a stored desired set speed with an actual speed and adjusting the throttle opening. When the brake pedal or clutch pedal is operated in this state, the constant speed traveling control is released and the engine brakes to enter the deceleration state.

Some of the above-described vehicle constant-speed traveling devices have a so-called resume function that automatically returns to the set speed before pedal operation when the above pedal operation is stopped and the resume switch is turned on (Japanese Patent Laid-Open No. Sho 61-206). 56-99518).

When the actual vehicle speed V is lower than the vicinity of the set speed (V <Vm−ΔV), for example, ΔV = 3 km / h, the device having the resume function automatically returns to the set speed Vm. The vehicle acceleration is calculated every cycle (for example, 0.3 sec), and the acceleration is constant acceleration (for example, 2 km / (h · se
While the constant acceleration control is performed so as to be c)), it is configured to switch to the normal constant speed traveling control when the speed is near the set speed (V ≧ Vm−ΔV).

[Problems to be Solved by the Invention] However, in such a conventional vehicle constant-speed traveling device, a large disturbance such as a gradient resistance is added to a normal traveling resistance such as when traveling on a road with many undulations. When added, it is difficult to maintain the acceleration constant by the constant acceleration control using the feedback as described above, and there is a problem that the throttle opening is unnecessarily changed and the riding feeling is deteriorated.

The present invention was devised in view of such circumstances, and even when a large disturbance such as a gradient resistance is added to the normal running resistance during the operation of the resume function, such as when driving on a road with a lot of ups and downs, the setting is made. An object of the present invention is to provide a constant speed traveling device for a vehicle capable of maintaining a constant acceleration for returning to near the speed.

[Means for Solving Problems] In order to achieve this object, the present invention has a speed detecting means 201 for detecting the speed of a vehicle, and a storage means 202 for storing a desired speed for constant speed traveling. The control means 204 including a function of operating the speed adjusting means 203 by comparing the speed detected by the speed detecting means with the stored speed stored by the storing means, and the constant speed traveling control are temporarily released. In the vehicle constant-speed traveling device including the resume means 205 for automatically returning from the state to the stored speed, the estimating means 206 for estimating the traveling resistance at every moment, and the traveling resistance estimated by the estimating means A calculating means 207 for calculating a desired state of the speed adjusting means capable of returning to the stored speed at a desired acceleration, and a signal for making the speed adjusting means into the desired state calculated by the calculating means. Signal generating means 208 for generating a signal.

[Operation] In the vehicle constant speed traveling device having such a configuration, the running resistance is estimated every moment before the resume function is activated, and the desired running resistance is obtained immediately after the resume function is activated. The speed adjusting means is controlled so that the vehicle can travel at a constant acceleration.

Embodiment An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a microcomputer 3 including control means for comparing a desired set speed for constant speed traveling stored in the storage means with an actual vehicle speed and outputting an opening command signal to the throttle actuator 1. It is a block diagram centering on. The throttle actuator 1 is of a pneumatic type or a motor type and is connected to a throttle 7 as a speed adjusting means in the throttle chamber 5 by a wire 9, and the throttle 7 is connected to an accelerator pedal 11 by a wire 9.

Each output signal from a set switch 13 that activates the present device, a brake switch 15 that interlocks with a brake pedal (not shown), and a clutch switch 17 that interlocks with a clutch pedal (not shown) is input to the microcomputer 3. The brake switch 15 and the clutch switch 17 are turned on by operating the respective pedals, and if either of them is turned on, the constant speed traveling control is released.

The resume switch 19 as a resume means is turned on when the pedal operation is stopped after releasing the constant speed traveling control as described above, and the microcomputer 3 which receives this ON signal has a desired set speed in the constant speed traveling state before the release. It has a so-called resume function that automatically returns to the.

The vehicle speed sensor 21 outputs a voltage proportional to the vehicle speed, and the throttle opening sensor 23 outputs a voltage proportional to the throttle opening. The A / D converter 25 receiving each output signal converts an analog quantity into a digital quantity and inputs the signal into the microcomputer 3. Further, the signal of the crank angle sensor 27 used for measuring the engine speed is input to the microcomputer 3.

The engine torque table 29 shows the throttle opening θ and the engine speed Ne from the microcomputer 3 every moment.
The engine torque database is written in the ROM (Read Only Memory) so that the engine torque Te can be read by applying the. Table 1 shows the contents of the engine torque table 29.

The throttle opening table 31 has a throttle opening database written in the ROM so that the target throttle opening θs can be read if the running resistance and the desired set speed are given from the microcomputer 3.
Table 2 shows the contents of the throttle opening table 31.

The above Tables 1 and 2 are both for the V-type 2 turbo engine.

The reference numeral 33 indicates a transmission, which shifts the shift position in response to a control command from the microcomputer 3.

Next, the operation of the microcomputer 3 will be described based on the flowchart shown in FIG.

First, in step 101, it is determined whether or not the set switch 13 is turned on, and if it is turned on, the process proceeds to step 102 and the MAINFLA
At the same time as writing "1" to G, the current speed V is set as a desired set speed (memory speed) Vm, and the routine proceeds to step 103. On the other hand, if it is off, the process directly proceeds to step 103.
In step 103, it is determined whether or not the brake switch 15 or the clutch switch 17 is turned on. If it is turned on, the process proceeds to step 104 to write "0" in MAINFLAG and proceeds to step 105. Steps 101 to 104 described above are parts that determine whether to start or stop the operation of the present apparatus.

If the brake switch 15 or the clutch switch 17 is off in step 103, the process directly proceeds to step 105, where it is determined whether or not the resume switch 19 is turned on. If it is on, the process proceeds to step 106 and RESFLAG is set to " Write 1 ", throttle 7 is fully closed (throttle opening θ
A throttle drive command is output so that it becomes (= 0), and it progresses to step 113.

On the other hand, if it is determined in step 105 that the resume switch 19 is off, and if RESFLAG is determined to be “1” in the next step 107, that is, the moment the resume switch 19 is turned off, the process proceeds to step 108, where RESFLAG is set. Write "0" and "1" to MAINFLAG. Next Step 10
At 9, the constant acceleration control for opening the throttle, which is normally fully closed at this time, to a target throttle opening θs, which will be described later, is started, and the routine proceeds to step 111. In step 111, RESOFFFLAG
Is set to "1" and the process proceeds to step 113.

If RESFLAG is determined to be "0" in step 107, that is, if the resume switch 19 remains off, the process proceeds to step 113. The above steps 105 to 111 indicate the processing when the resume switch 19 is turned on or off.

Here, MAINFLAG = 1 ... Constant speed traveling control MAINFLAG = 0 ... Constant speed traveling control release RESFLAG = 1 ... Resume switch ON RESFLAG = 0 ... Resume switch OFF RESOFFFLAG = 1 ... Constant acceleration control (Throttle opening θ = Target throttle opening θs) RESOFFFLAG = 0 ... Indicates completion of constant acceleration control.

From step 113 to step 119, step 11 is executed at every elapse of a predetermined period Δt (for example, Δt = 1 sec) in the acceleration α calculation unit.
Each processing from 7 to step 119 is performed. First, step 11
In 3 enter the actual speed V, and in step 114 this speed V
Is within the range of 40 km / h <V <100 km / h. If V ≦ 40 km / h and V ≧ 100 km / h, in step 115
Set MAINFLAG to “0” and proceed to step 116. On the other hand, if the speed V is within the range of 40 km / h <V <100 km / h in step 114, the process directly proceeds to step 116.

In step 116, it is determined whether or not the predetermined period Δt has passed, and if it has passed, the process proceeds to step 117. step 1
In step 17, the speed V ₁ one control cycle before is retrieved from the memory, and in step 118, the acceleration α is calculated according to the following equation (1).

α = (V ₁ −V) / Δt (1) Further, in step 119, the speed V is set to V ₁ and stored in the memory, and the flow proceeds to step 121. On the other hand, in step 116, the predetermined period Δt
If has not elapsed, the process directly proceeds to step 121.

Steps 121 to 124 represent the target throttle opening degree calculation unit. First, at step 121, the throttle opening θ
Is input, the engine speed Ne is measured from the number of pulses of the crank re-signal within a predetermined time, and the routine proceeds to step 122. In step 122, the engine torque Te is read from the engine torque table shown in Table 1 above based on the obtained throttle opening θ and engine speed Ne.

By the way, the transmission position m in this state, the engine torque Te obtained in step 122, the acceleration α obtained in step 118, and the estimated running resistance have the relationship of the following equation (2).

Te = (R / γm ・ ηm ・ γn ・ ηn) {+ (W ・ α / g) + (J ・ α / R ² )} …… (2) J = J _W ； γn ²・ ηn ・ Jp + ( J _T + J _E ) / γm ² · γn ² · ηm · ηn (3) [where γm: transmission gear ratio of each gear, ηm: transmission efficiency of each gear, γn: final reduction ratio, ηn: Final transmission efficiency, R: tire radius, W: vehicle weight, g: gravitational acceleration, J _W: wheel inertia, Jp: Pera inertia, J _T: turbine inertia, J _E: engine inertia] (2) an estimated running resistance Solving for, ＝ (γm ・ ηm ・ γn ・ ηn / R) Te − (W ・ α / g) − (J ・ α / R ² ) …… (4) Calculation of this equation (4) is done in step 123. Done.

In the next step 124, the target throttle opening θs is read from the throttle opening table shown in Table 2 above.
This reading procedure is performed as follows.

(I) Estimated engine torque e for traveling at a constant acceleration with acceleration a with respect to the estimated traveling resistance obtained in step 123
Can be obtained by the following equation (5) with α = a in the above equation (2).

e = (R / γm ・ ηm ・ γn ・ ηn) {+ (W ・ a /
g) + (J · a / R ² ) ... (5) (ii) The throttle opening corresponding to the engine torque e obtained by the above equation (5) and the engine speed Ne obtained in step 121 is set to the above-mentioned The target throttle opening θs is read from the throttle opening table shown in Table 2.

As described above, according to the steps (i) and (ii), constant acceleration traveling can be performed at a desired acceleration in accordance with the traveling resistance that changes from moment to moment depending on the road gradient, wind direction, etc., and the target throttle opening can also be accurately estimated.

When the target throttle opening degree θs has been calculated by the target throttle opening degree calculation section in steps 121 to 124, the process proceeds to the flag check section shown in steps 125 to 128. In the flag check section, first, in step 125, M
It is determined whether or not AINFLAG is "0", and if MAINFLAG = 0 (during constant speed travel control cancellation), the routine proceeds to step 126, the throttle 7 is fully closed (θ = 0), and the routine returns to step 101. On the other hand, when MAINFLAG = 1 (during constant speed running control), the routine proceeds to step 127, where it is determined whether RESOFFFLAG is "0" and RESOF
When FFLAG = 0 (constant acceleration control is completed), the routine proceeds to step 128, where constant speed traveling control is performed to match the speed V with the set speed Vs, and then the routine returns to step 101. RESOFFFLAG = in step 127
If it is 1 (during constant acceleration control), the process proceeds to step 129.

Steps 129 to 131 are the constant acceleration control completion determining unit. First, step 129 continues constant acceleration control with the actual throttle opening θ as the target throttle opening θs, and proceeds to step 130. In step 130, it is determined whether or not the speed V has reached the vicinity of the stored (set) speed Vm.
After proceeding to 1, RESOFFFLAG = 0 (constant acceleration control completion) and returning to step 101, while less than the memory speed (V <Vm- △
If it is determined to be V), the process directly returns to step 101.

The above flow chart can be easily realized by an ordinary microcomputer, and can be applied to various vehicles as long as the vehicle specification data of equation (2) and the engine performance data of Tables 1 and 2 are known. .

[Advantages of the Invention] As described above, according to the present invention, the running resistance is estimated every moment before the resume function is activated, and immediately after the resume function is actuated, the speed adjusting means is based on the latest estimated running resistance. Since the state of is controlled by feedforward, even when a large disturbance such as a gradient resistance is added to the normal running resistance such as when running on a road with a lot of undulations, constant acceleration running at a desired acceleration can be realized, Moreover, as a result of keeping the speed adjusting mechanism stable, a good ride feeling can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of a vehicle constant-speed traveling device according to an embodiment of the present invention, FIG. 2 is a flow chart of a microcomputer showing its operation, and FIG. 3 ... Microcomputer 7 ... Throttle (speed adjusting means) 19 ... Resume switch (resume means) 21 ... Vehicle speed sensor (speed detecting means)

Claims (1)

[Claims] 1. A speed detecting means for detecting a speed of a vehicle, a storing means for storing a desired speed for performing constant speed traveling, a speed detected by the speed detecting means and a memory stored by the storing means. Constant speed running for a vehicle provided with a control means including a function of operating a speed adjusting means by comparing the speed with a speed, and a resume means for automatically returning to the stored speed from a state where the constant speed running control is temporarily released. In the device, an estimating means for estimating the running resistance every moment, and a computation for computing a desired state of the speed adjusting means capable of returning to the storage speed at a desired acceleration under the running resistance estimated by the estimating means. A constant-speed traveling device for a vehicle, comprising: a means and a signal generating means for generating a signal for causing the speed adjusting means to be in a desired state calculated by the calculating means.