JPH04154435A - Auto-cruise device with retarder - Google Patents

Abstract

PURPOSE:To approach vehicle speed to the target cruise vehicle speed without stepping a brake pedal or shifting down to improve operability by using an engine output control means together with a retarder means to restrain increase of vehicle speed if necessary. CONSTITUTION:The device main body is provided with a controller 1 composed of a cruise controller 2 to control output of an engine 10 and a retarder controller 3 to control operation of a retarder 40. In the case of performing auto-cruise control, the cruise controller 2 adjusts the fuel injection quantity of a fuel injection pump 11 through an actuator 12. Meanwhile, when a main switch 5 is operated to be ON and a second main relay switch 7 is ON, relay coils 31a-34a are excited with the retarder controller 3 to operate a first to a fourth retarder relay switches 31-34 to be ON, corresponding eddy current generating coils 51a-58a are electrified to generate eddy current, and braking force is generated in the retarder 40.

Description

Detailed Description of the Invention A11 Purpose of the Invention (Field of Industrial Application) The present invention relates to a vehicle equipped with an auto-cruise device and a retarder, and more specifically, the operation of the auto-cruise device can be assisted by the retarder. Concerning what was done.

(Prior Art) An auto-cruise device is a device that maintains the vehicle speed at a target cruise speed without the driver's accelerator operation, and has been widely used as a travel control device for automobiles. Current auto-cruise devices are configured to maintain the vehicle speed at a target cruise vehicle speed regardless of changes in the traveling load by automatically controlling the accelerator of the driving engine to control the engine output.

(Problem to be Solved by the Invention) As described above, the current auto-cruise device only controls the engine output, so there is a problem in that there are limits to that control. For example, when driving down a long downhill slope with the auto-cruise device activated, controlling the engine output alone may not be able to suppress the increase in vehicle speed, and the vehicle speed may increase beyond the target cruise vehicle speed. especially,
When a large truck etc. is traveling with a load on it,
Because of its large weight, the acceleration of gravity is large, and this situation is likely to occur.

In such a case, the driver must step on the brake or downshift to reduce the vehicle speed.

However, the auto-cruise system is deactivated when the brake pedal is pressed or the clutch pedal is pressed to downshift, so the auto-cruise system must be activated again in order to resume auto-cruise driving after the vehicle speed has decreased. The problem is that the operation is cumbersome and puts a heavy burden on the driver.

In view of these problems, the present invention focuses on the effect of a retarder as a means of suppressing vehicle speed, and utilizes the effect of this retarder in the above-mentioned cases to reduce the vehicle speed without turning off the auto cruise device. An object of the present invention is to provide an auto-cruise device capable of reducing the vehicle speed to a target cruise speed.

Configuration of the Invention (Means for Solving the Problems) In order to achieve such an object, the autocruise device according to the present invention includes a control system for the engine output control means for controlling the output of the engine and the driving force transmission system. The controller controls the operation of the retarder means for generating power. As long as the actual vehicle speed detected by the vehicle speed sensor remains lower than the retarder operating vehicle speed (>target cruise vehicle speed), this controller controls the operation of only the engine output control means to change the actual vehicle speed to the target cruise vehicle speed. Control is performed to bring the actual vehicle speed closer to the target cruise vehicle speed, but if the actual vehicle speed exceeds the retarder activation vehicle speed, control is performed to bring the actual vehicle speed closer to the target cruise vehicle speed using both engine output control means and retarder operation control. It has become.

Note that the retarder means is composed of an eddy current type retarder having a plurality of eddy current generating coils, and when the actual vehicle speed exceeds the retarder activation vehicle speed, the plurality of eddy current generating coils are selectively activated by the controller. Preferably, the actuation of the retarder means is controlled.

(Function) When using the auto-cruise device with a retarder configured as described above, when the vehicle speed increases beyond the target cruise vehicle speed, such as when driving on a long downhill slope with the auto-cruise device activated, This vehicle speed or retarder activation vehicle speed (〉
When the cruise vehicle speed exceeds the target cruise vehicle speed, the controller operates the retarder means. As a result, the engine output control means and the retarder means are used together to suppress an increase in vehicle speed, and the vehicle speed can be brought close to the target cruise vehicle speed without depressing the brake pedal or downshifting.

Although retarder means include fluid retarders and eddy current (electromagnetic) retarders, the use of an eddy current retarder with a plurality of eddy current generating coils is particularly recommended for its good controllability. Therefore, it is preferable.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the configuration of an autocruise device with a retarder according to the present invention. This device includes a controller 1 that includes a cruise controller 2 that controls the output of an engine 10 and a retarder controller 3 that controls the operation of a retarder 40. This controller 1 is connected to a battery 8 via a line 101 and a first main relay switch 6. 1st main relay switch 6
The fill 6a is connected to the line 102 and the main switch 5
When the main switch 5 is turned on, the coil 6a is excited and the first main relay switch 6 is turned on. This allows line 101
An on signal is input to the controller 1 via the controller 1, and the auto cruise control by the controller 1 is started.

The engine 10 in this example is a diesel engine, and its output is controlled by adjusting the fuel injection amount of the fuel injection pump 11. This control is normally performed by transmitting the depression of the accelerator pedal 13 to the fuel injection pump 11 via the cable 13a, but when performing auto cruise control, it receives a drive signal from the cruise controller 2. This is done by adjusting the fuel injection amount of the fuel injection pump 11 using an actuator (for example, a step motor) 12 driven by the fuel injection pump 11.

A transmission 15 is integrally connected to the output shaft of the engine 10, and a vehicle speed sensor 16 is disposed at the output portion of the transmission 15. Vehicle speed sensor 16 detects the output rotation of transmission 15 and sends this detection signal to cruise controller 2, and cruise controller 2 calculates actual vehicle speed Va from this detection signal.

A set switch 21 and a resume switch 22 are connected to the cruise controller 2, and by operating these switches 21 and 22, a target cruise vehicle speed vO during auto cruise driving is set and changed. Furthermore, this cruise controller 2 includes a brake switch 23 that is operated in conjunction with the brake pedal.
It is connected to a clutch switch 24 that is operated in conjunction with the clutch pedal, and when the brake pedal or clutch pedal is depressed, one of the corresponding switches 23 and 24 is turned on. When the brake switch 23 or the clutch switch 24 is turned on, the cruise controller 2 receives this signal and releases the automatic cruise control.

The retarder controller 3 receives the signal from the cruise controller 2 and switches the first to fourth retarder relay switches 31.
34, and the L/- coils 31a to 34a of these relay switches 31 to 34 are connected to the retarder controller 3. The first to third retarder relay switches 31 to 34 each have one end connected to the second
It is connected to the battery 8 via the main relay switch 7 and line 105, and the other end is connected to the eddy current generating coils 51a to 58a of the eddy current type retarder 40 as shown.

Therefore, when the main switch 5 is turned on and the second main relay switch 7 is turned on, a signal from the retarder controller 3 causes relay coils 31a to 3
4a is energized and the first to fourth retarder relay switches 3
When the coils 1 to 34 are turned on, the corresponding eddy current generating coils 51a to 58a are energized, eddy currents are generated, and a braking force is generated in the retarder 40.

The configuration of this eddy current type retarder 40 will be explained based on FIGS. 2 and 3.

The eddy current retarder 40 is disposed on the output shaft of the transmission 15 or on the propeller shaft connected thereto, and brakes the rotation of the output shaft or the propeller shaft. This eddy current type retarder 4o includes a fixed housing 41 that is coupled to the vehicle body 19 and held fixed, a bracket 42 coupled to this, a fixed part that includes a plurality of electromagnets 51 to 58 attached to this bracket 42, etc. Fixed housing 4
1, a shaft 45 is rotatably held via bearings 44a, 44b, and a flange coupling 46a is connected to both ends of the shaft 45.

46b1 flange coupling 46a.

The bracket 42 constituting the fixing part has a cylindrical part, and eight electromagnets 51 to 58 are radially attached at approximately equal intervals on the outer peripheral surface of the cylindrical part by poles 51c to 58C. Each of the electromagnets 51 to 58 includes a core member 51b to 58b made of a ferromagnetic material such as iron, and an eddy current generating coil 51 wound around the core member 51b to 68b.
It is composed of a to 58a.

On the other hand, flange couplings 48a are provided at both ends of the shaft 45 constituting the rotating portion by splines.
, 4eb are connected, and the inner peripheral end of the rotating drum 47 is bolted to the flange coupling 46a. The cylindrical portion of the rotating drum 47 covers the electromagnet 10, and in this state, the outer peripheral side end surfaces of the core members 51b to 58b are
It is located close to and opposite to the inner peripheral surface of the rotating drum 47. Note that a plurality of heat radiation fins 47a are formed on the outer periphery of the cylindrical portion of the rotating drum 47, and further, a plurality of heat radiation fins 47a are formed in the center of the cylindrical portion and penetrate in the radial direction for discharging high-temperature air inside. A hole 47b is formed.

In the eddy current brake with the above configuration, the flange couplings 48a and 46b are connected to the output shaft of the transmission 15 or the propeller shaft connected thereto, and the rotating portion rotates together with the output shaft and the propeller shaft. In this state, the eddy current generating coils 51a~ of the electromagnets 51~58
When 58a is energized, a magnetic flux is generated within core members 51b-58b in the axial direction (radial direction of the eddy current retarder), and this magnetic flux flows in the direction of its extension and traverses the cylindrical portion of rotating drum 47. Therefore, an eddy current is generated in the cylindrical portion of the rotating drum 47, and due to the action of this eddy current, the rotating drum 47
A braking torque opposite to the direction of rotation is generated, and the rotating shaft is braked.

Auto-cruise control in the retarder-equipped auto-cruise device configured as described above will be explained with reference to the flowchart in FIG. 4.

Since this auto cruise control is started with the main switch 5 turned on and the first and second main relay switches 6.7 turned on, first, step S
1, it is determined whether the main switch 5 is on. When the main switch 5 is off, auto-cruise control is not performed, so the control flow ends.

On the other hand, when the main switch 5 is on, step 8
2 to S4, the target cruise vehicle speed VO set by the set switch 21 and the resume switch 22 is detected in step S2), the actual vehicle speed Va is detected from the signal from the vehicle speed sensor 16 in step S3), and both vehicle speeds Vo+Va are detected. The difference ΔV (=Va−Vo) is calculated.

Next, in step S5, it is determined whether the absolute value of this vehicle speed difference ΔV is greater than a first predetermined value V.

This first predetermined value v1 is a value indicating an allowable variation range of vehicle speed during autocruise driving, and in autocruise control, control is performed to suppress the vehicle speed within this allowable range. Therefore, when 1ΔV l :5v, the process proceeds to step S6, and a drive signal that maintains the output of the engine IO as it is is output to the actuator 12 of the fuel injection pump 11. On the other hand, when 1ΔVl>V, the process proceeds to step S7, and it is determined whether the vehicle speed difference ΔV is larger than a second predetermined value V2. When ΔV>v2, the process proceeds to step S8, and carrot output control is performed by outputting a drive signal to the actuator 12 so as to make this vehicle speed difference ΔV zero, that is, to bring the actual vehicle speed Va closer to the target cruise vehicle speed Vo. .

During normal driving, such actuator 12
The fuel injection amount is controlled by the drive control of the engine 1.
It is possible to make the actual vehicle speed Va almost match the target cruise vehicle speed VO by simply performing zero output control, but engine output control alone is not sufficient when driving down a long downhill slope with a loaded vehicle. There are times when the vehicle speed increases rapidly. In this case, the present device uses an eddy current retarder 40 in combination to suppress the increase in vehicle speed. In this case, the eddy current retarder 40 is activated when the actual vehicle speed Va becomes larger than the target cruise vehicle speed VO by a second predetermined value v, that is, when ΔV>V2. That is, the vehicle speed is greater than the target cruise vehicle speed vO by the second predetermined value v2, or the vehicle speed at which it is determined whether or not to operate the retarder 40 (
retarder operating vehicle speed).

Therefore, in step S7, it is determined whether the vehicle speed difference ΔV is larger than the second predetermined value v2, and Δv
>v2, the process proceeds to steps 89 to S10, and the target actual vehicle speed Va is achieved by using both the engine output control by the drive control of the actuator 12 and the retarder control by the operation control of the first to fourth retarder relay switches 31 to 34. Control is performed to bring the cruise vehicle speed closer to Vo.

As a result, the actual vehicle speed Va, which has increased until ΔV > V 2, is decelerated and approaches the target cruise vehicle speed Vo. Here, in step Sll, it is determined whether the actual vehicle speed Va has been decelerated until it almost matches the target cruise vehicle speed Vo.

The control in step S9, step SIO, and step SIO are used in combination until Va becomes VO, and the current control flow ends.

Thereafter, auto cruise control is performed by repeating the above control flow at predetermined intervals.

In addition, the operation control of the first to fourth retarder relay switches 31 to 34 in the retarder control of step SIO is performed based on Δ
All relay switches 31 to 34 may be turned on at the same time when v>v2, but relay switches 31 to 34
It is preferable to carry out control such that these are operated in sequence, since smooth deceleration can be performed. Specifically, Δ
When V>v2, first, only the first retarder relay switch 31 is turned on to energize only the electromagnets 51 and 55, and if sufficient deceleration cannot be achieved with this, the cylinder 2 It is desirable to perform control such that the fourth retarder relay switches 32 to 34 are turned on from then on.

An example of a change in vehicle speed when driving on a road as shown in FIG. 5A with the auto cruise control described above is shown in FIG.
This is shown in Figure B. This road is flat from point A to point B, downhill from point B to point C, and flat again from point C to D.

Here, a case is shown where auto-cruise control is performed by setting 80 kII/H as the target cruise vehicle speed. A
Since the road from point B to point B is flat, the vehicle speed can be adjusted to approximately the target cruise vehicle speed (=80 km/h) by simply controlling the engine output.
H) can be maintained. In this case, the actual vehicle speed Va
is controlled so that it falls within the allowable variation range shown by lines L1 (lower limit) and L2 (upper limit) in the figure. The vehicle speed indicated by line L1 is a first predetermined value v1 lower than the target cruise vehicle speed Vo, and the vehicle speed indicated by line L2 is a first predetermined value V higher than the target cruise vehicle speed Vo. For example, the first predetermined value V1 is 2+i/H
In this case, the vehicle speed indicated by line L1 is 88 km/H, and the vehicle speed indicated by line L2 is 92 km/H.

Next, when the vehicle passes point B and starts going downhill, the actual vehicle speed Va cannot be maintained at the target cruise vehicle speed Vo by engine output control alone, and the actual vehicle speed Va gradually increases. Here, in this example, the second predetermined value v2 is 10
■/H is set, and the retarder operating vehicle speed in this case is 90++/H. Therefore, when the vehicle speed gradually increases on a downhill slope and reaches the retarder activation vehicle speed shown by line L3 (time t+), in addition to engine output control by the cruise controller 2, the retarder controller 3 activates the eddy current retarder 40. Control begins. As a result, the actual vehicle speed Va is decelerated, and at the time (t2) when the actual vehicle speed Va is decelerated to the target cruise vehicle speed V o C = 80 km/H), the operation of the tarp 40 is canceled and the engine output control is resumed. Only.

In this example, at this time (t2), the vehicle is still traveling downhill, so the actual vehicle speed Va increases again, and at the time when the actual vehicle speed Va reaches the retarder activation vehicle speed (=90 km/H) ( At t3), the retarder 40 is activated again. Therefore, the actual vehicle speed Va changes as shown in FIG. 5B.

After this, when the vehicle passes point C and reaches a flat road,
The actual vehicle speed Va is controlled to substantially match the target cruise vehicle speed Vo only by controlling the output of the engine.

In the example explained above, eight electromagnets are arranged in the eddy current type retarder 40;
Of course, the number of relay switches that control the energization of this electromagnet is not limited to four.
It is not limited to individuals. Further, in the above example, an eddy current type retarder is used as the retarder, but a fluid type retarder may be used instead.

Furthermore, in the above embodiment, an example using a diesel engine was shown, but the same applies to a gasoline engine.
In the case of a gasoline engine, the engine output is controlled by controlling the throttle opening, for example.

C.1 As described in detail, according to the present invention, as long as the actual vehicle speed detected by the vehicle speed sensor remains lower than the retarder activation vehicle speed (> target cruise vehicle speed), only the engine output control means is activated. Operation control is performed to maintain the actual vehicle speed approximately at the target cruise vehicle speed, and when the actual vehicle speed exceeds the retarder activation vehicle speed, the operation control of the engine output control means and the retarder means are used together to reduce the actual vehicle speed. Since the vehicle speed is controlled to approach the target cruise vehicle speed, for example, when the vehicle speed increases beyond the target cruise vehicle speed, such as when driving on a long downhill slope with the auto cruise device activated, This vehicle speed or retarder activation vehicle speed (〉
When the target cruise vehicle speed is exceeded, the retarder means is activated. As a result, the engine output control means and the retarder means are used together to suppress the increase in vehicle speed, and the vehicle speed can be brought closer to the target cruise vehicle speed without depressing the brake pedal or downshifting, even when driving downhill. Stable auto-cruise control can be performed, reducing driver fatigue and driving more safely.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit diagram showing an auto cruise device with a retarder according to the present invention, Fig. 2 is a front view of an eddy current retarder, Fig. 3 is a sectional view of the eddy current retarder, and Fig. 4 is the above auto cruise device. FIG. 5A is a schematic diagram showing an example of a road on which auto-cruise driving is performed, and FIG. 5B is a graph showing changes in vehicle speed when auto-cruising on this road. 1... Controller 5... Main switch 8
... Batch IJ -10 ... Engine 11 ... Fuel injection pump 15 ... Transmission 16 ... Vehicle speed sensor 21 ... Set switch 22 ... Resume switch 31 to 34 ... Retarder relay Switch 40... Eddy current retarder 45... Shaft 47... Rotating drum 51
~58...Electromagnet

Claims (1)

[Scope of Claims] 1) Target vehicle speed setting means for setting a target cruise vehicle speed; a vehicle speed sensor for detecting the actual vehicle speed of the vehicle; and engine output control means for controlling the output of an engine for driving the vehicle; The retarder means is disposed in the driving force transmission system of the vehicle and generates a braking force in the driving force transmission system, and the controller controls the operation of the engine output control means and the retarder means. The controller controls the operation of only the engine output control means when the actual vehicle speed detected by the vehicle speed sensor remains lower than the retarder activation vehicle speed, which is set higher than the target cruise vehicle speed by a predetermined vehicle speed. to control the actual vehicle speed to approach the target cruise vehicle speed, and when the actual vehicle speed exceeds the retarder activation vehicle speed,
An auto cruise device with a retarder, characterized in that the engine output control means and the operation control of the retarder means are used together to control the actual vehicle speed to approach the target cruise vehicle speed. 2) The retarder means is an eddy current type retarder having a plurality of eddy current generating coils, and when the actual vehicle speed exceeds the retarder operating vehicle speed, the controller selectively controls the plurality of eddy current generating coils. 2. The auto cruise device with a retarder according to claim 1, wherein the retarder means is actuated to control the operation of the retarder means.