JPS58141909A - Control system of shock absorber - Google Patents

Abstract

PURPOSE:To automatically control damping force of a shock absorber, by detecting a starting condition or a change of speed or the like. CONSTITUTION:Under a condition with a car speed V below a reference car speed VL, if all starting conditions are satisfied, a microcomputer 11 respeatedly executes a closed loop of a step 102 or 109, accordingly immediately after starting, damping force of shock absorbers from 12 to 15 is set higher to prevent front lifting and rear sinking at a rapid start. Then under this condition the speed V becomes at least the speed VL, even when the starting condition is released, the damping force is still set higher during a prescribed period t1. Then if t=t1, the microcomputer 11 is inverted to a decision result YES in a step 112, and the absorbers from 12 to 15 are decreased lower to ensure good comfortableness of riding in a normal running condition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stain absorber control system that reduces the damping force of a shock absorber when the speed of an automobile changes rapidly, such as when starting.

Conventionally, cars equipped with shock absorbers for automatic damping control have lowered the damping force of the shock absorber on good roads such as general paved roads to improve the ride comfort of the car, and on rough roads such as unpaved roads. In this system, the damping force of the shock absorber is increased to prevent the differential of the automobile from coming into contact with the ground, and to ensure the maneuverability of the automobile on rough roads.

However, since the damping force is generally switched manually or automatically by detecting high and low speeds of the vehicle, it is difficult to adjust the damping force to the actual driving conditions of the vehicle. Moreover, this control method cannot prevent the car from rising and falling when starting or suddenly braking, and even the shock absorber for automatic damping force control cannot fully demonstrate its function. There was a similar topic.

An object of the present invention is to provide a shock absorber control system that automatically controls the damping force of a shock absorber by detecting, for example, starting conditions of a vehicle or changes in vehicle speed, thereby solving the above-mentioned conventional problems. It's about solving.

The present invention will be described below with reference to the drawings.

As an input part of the microcomputer 11, which is an example of arithmetic control means, there are a vehicle speed sensor 1 that generates an output corresponding to the speed of the automobile, and an engine rotation speed sensor 2 such as an ignition coil that generates an output corresponding to the engine rotation speed.
It is operated by an accelerator opening sensor 3 such as a potentiometer that is linked to the accelerator pedal and generates an output corresponding to the accelerator opening, and a shift lever that generates an output corresponding to the transmission position, such as an on/off output. Transmission position sensor 4 such as a switch
and a clutch connection state sensor 5 such as a switch operated by a clutch system member that generates an output corresponding to the clutch connection state, for example, an on/off output, are connected via corresponding buffers 16 to 10, respectively.

The microcomputer 11 to which the outputs from the sensors 1 to 5 are input is configured to adjust the output V from the vehicle speed sensor 1 to a reference vehicle speed of, for example, several Kmi/H, which is the upper limit starting speed of the vehicle stored in the microcomputer 11 in advance. The corresponding output V satisfies the relationship V≦VL, and the output R from the engine rotation detection sensor 2 is stored in the microcomputer 11 in advance, for example, an output corresponding to the reference rotation speed for engine idle rotation instruction. In relation to R1, R>Ri is satisfied, and the output S from the accelerator relation sensor 3 is nI stored in advance in the microcomputer 11.
8>3ifl1 in relation to the output s1 corresponding to the standard opening of the accelerator pedal when starting the l-skewer
In addition, the output from the transmission position sensor 4 matches the on/off switch when the transmission is not in the neutral or parking position, which is stored in advance in the microcomputer 11, and the output from the clutch engagement state sensor 5 matches the switch on or off when the transmission is not in the neutral or parking position. When all these conditions are satisfied, automatic damping force control shims are provided corresponding to each of the four wheels of the automobile. Actuators such as electromagnetic solenoids and DC motors (coils 16 shown in FIG. 2 representing each stain absorber 12) of the absorbers 12 to 15 are excited via drive circuits 17 to 20.

Figure 2 shows each sensor 1 to 5 and the microcomputer 1.
Shock absorbers 12 to 15 for automatic damping force 111111 controlled by the upper movable part 21
A coil 16 electrically connected to the drive circuit 17, 18, 19 or 20, and a ring which is moved and held upward together with the connecting rod 22 by the magnetic force generated when the coil 16 is energized. A shaped core 23 is provided.

When the coil 16 is in a de-energized state, the flow rate ll11vA valve 24 at the tip of the connecting rod 22 and the piston 26 provided at the tips of the piston rods 2 and 5 are maintained in the state shown in the figure, and the first oil chamber The interaction between the oil chamber 40 and the second oil chamber 50 allows oil to flow relatively easily. Exchange 6'! If J, the damping force of the shock absorber 12, 13, 14 or 15 is maintained at a normal level, ie, at a low level.

On the other hand 1. When the F coil 16 is energized by the drive circuit 17, 18, 19 or 20, the core 23 receives an upward force due to the generated magnetic force, and together with this core 23, the connecting rod 2
2 moves upward, and the flow control valve 24 opens into the first oil chamber 40.
Since the passage 28 communicating with the valve chamber 27 is blocked, the flow resistance between the first oil chamber 40 and the second oil chamber 50 is at a high level, so that the shock absorbers 12, 13, .
14, my father's 15 has a higher damping force. and coil 1
6 is in the energized state, the flow control valve 24 continues to block the passage 28 and the damping force of the shock absorber 12.13.1, 4 or 15 is maintained at a high level.

Next, the processing operation of this embodiment configured as described above will be explained.

When the key switch 30 is turned on, the microcomputer 11 starts processing as schematically illustrated in FIG.

In FIG. 3, 101 indicates data corresponding to the reference value VLlRilSi etc. for each sensor 1 to 5 output.
Represents the step of performing an initial set such as storing to M.

Reference numeral 102 represents a step of calculating the vehicle speed V based on the speed signal inputted from the vehicle speed sensor 1 via the buffer 6.

103 represents a step of determining whether the vehicle speed V is less than or equal to a preset reference vehicle speed VL.

Reference numeral 104 represents a step of calculating the engine rotation speed R based on the rotation speed signal inputted from the engine rotation speed sensor 2 via the buffer 7.

105 represents a step of determining whether the engine rotation speed R is equal to or higher than a preset reference rotation speed R1.

106 represents a step of determining whether or not the accelerator opening degree S inputted from the accelerator WIIJ degree sensor 3 via the buffer 8 is greater than or equal to a preset reference opening degree Si.

107 represents a step of determining whether the on/off signal inputted from the transmission position sensor 4 via the buffer 9 is an on/off signal corresponding to a preset neutral position.

Reference numeral 108 represents a step for determining whether or not the on/off signal received from the clutch connection state sensor 5 via the buffer 10 is an on/off signal corresponding to a preset clutch operator. This represents the step of outputting a control signal to the drive circuits 17 to 20 to increase or maintain the damping force of the absorbers 12 to 150. Also in this step, the damping cuff flag is set to indicate that the damping force is high.

110 represents a step of checking the damping flag and determining whether or not the reduction capacity of the stain absorbers 12 to 15 is high in a state where the vehicle starting conditions determined in steps 103, 105 to 108 are not satisfied.

111 represents a step in which the timer is set to 1==1+ in order to maintain the reduced capital capacity for a certain period of time even after the start condition is canceled.

112 represents a step of determining whether the operating time of the timer has reached t-tl.

113 represents a step of outputting a control signal to the drive circuits 17 to 20 to maintain or reduce the damping force of the shock absorbers 12 to 15 to a normal level. Also, in this step, the capital reduction flag is reset to indicate that the damping force is lower.

In the shock absorber control method configured in this way, if the vehicle is in a stopped state before starting even if the ignition switch 30 is turned on, the vehicle speed V is equal to the reference vehicle speed VL.
Even if the engine rotation speed R is below the reference rotation speed R1, the accelerator opening S is also below the reference opening S1, or,
When any one of the outputs from the sensors 1 to 5 does not satisfy the starting conditions defined in each step 103, 105 to 108, such as when the transmission is in the neutral N position, the microcomputer 11 increases or maintains the damping force. No control signal is generated for
The capital reduction flag has also been reset.

Therefore, the microcomputer 11 repeatedly executes the closed loop of steps 110 and 113 from steps 103, 105 to 108 in FIG. Power is set low.

Next, in this state, shift the transmission to any position other than neutral, engage the clutch, and simultaneously press the accelerator pedal, the vehicle speed will increase to V! ! All starting conditions are set to W4 in a state where the vehicle speed is less than or equal to the semi-skew vehicle speed L.

For this reason, the microcomputer 11 repeatedly executes the closed loop of steps 102 to 109 in FIG. It is possible to prevent the front part of the vehicle from rising and the rear part to sink, thereby reliably preventing a decrease in the ride comfort of the vehicle when the vehicle starts suddenly.

Next, in this state, the vehicle speed V becomes equal to or higher than the reference vehicle speed VL, etc.
When the starting condition for any one of the sensors 1 to 5 is canceled, immediately after the starting condition is canceled, since the damping flag indicates a high damping force, the microcomputer 11 performs step 102 in FIG. Step 1101 Step 111, Step 112, Step 1 from any of Steps 103, 105 to 108
Even if the closed loop of 09- is repeatedly executed and the start condition is canceled, the reduction capacity of the shock absorber is still set to ^ during the predetermined period t1.

Next, when the value becomes 1-1+ in this state, the microcomputer 11 performs step 102 and step 103 because the determination result of step 112 is reversed to rYEsJ.
．． The closed loop of step 1101, step 111, step 112, and step 113 is repeatedly executed from any one of steps 105 to 108, and the jaw absorbers 12 to 15 are reduced to a normal level, that is, to a low level, to ensure good riding comfort in normal driving conditions. . By arbitrarily setting the above-mentioned 11 hours, it is possible to obtain a capital reduction control characteristic that matches the starting conditions of each vehicle.

Note that in this example. Instead of the starting condition corresponding to the engine speed R, the change i in the engine speed is compared with the reference change i stored in the microcomputer 11 in advance, and the starting condition 1 is determined as >lqi. Alternatively, instead of the starting condition corresponding to the accelerator opening degree S, the true amount of change in the accelerator opening degree may be compared with a reference change amount S1 stored in advance in the microcomputer 11,
i>Si may be used as one of the starting conditions, and in this case, the response of damping force control can be particularly improved.

Also, when starting on a hill at A71m, when the accelerator pedal is depressed while the brake is on, the damping force will be higher if the above-mentioned starting conditions are satisfied, so the driving feeling will be affected. It becomes possible to

Further, step 114 determines the condition shown in FIG. 4 as a starting condition, and step 11 determines whether the parking brake is on or off.
5 may be provided.

As explained above, the present invention is designed to reduce the damping force of the shock absorber in an automobile equipped with a shock absorber for automatic damping force of $13111 when the starting conditions of the automobile are satisfied.

Therefore, according to the present invention, it is possible to prevent a reduction in ride comfort in an automatic vehicle due to the front part of the vehicle rising up and the rear part sinking when the vehicle starts.

[Brief explanation of the drawing]

FIG. 1 is an electrical system diagram of one embodiment of the present invention, FIG. 2 is a broken cross-sectional view of shock absorbers 12 to 15, FIG. 3 is a flowchart for explaining the processing operation, and FIG.
The figure is a flowchart of another embodiment of the invention. 1... Vehicle speed sensor 2... Engine speed sensor 3... Accelerator opening sensor 4... Transmission position sensor 5... Clutch connection state sensor 11... Microphone [+ Computer 12 to 15...・Shock absorber agent Tsutomu Adachi, patent attorney Figure 1 0

Claims (1)

[Scope of Claims] 1. In an automobile equipped with an automatic damping force control shock absorber that can adjust damping force by changing flow path resistance due to actuator operation, preset automobile starting conditions are satisfied. A shock absorber control method characterized in that the actuator is operated in such a manner that the flow path resistance of the shock absorber is increased. 21-The starting condition is that the output from a vehicle speed sensor that generates an output corresponding to the speed of the vehicle is below a preset reference vehicle speed, and that the engine rotation speed sensor generates an output that corresponds to the engine rotation speed. The output from the accelerator opening sensor, which generates an output corresponding to the accelerator opening degree, becomes an output corresponding to the preset standard accelerator opening degree. and the output from a transmission position sensor that generates an output corresponding to the transmission position is an output corresponding to Iji↓-Tral. Shock absorber control method described. 3. Claim 2, characterized in that the starting condition includes generating an output corresponding to the clutch engagement state, and that the output from the clutch engagement state sensor becomes an output corresponding to the clutch operator. shock absorber I
J Ill method. 4 The above start condition' generates an output corresponding to the foot brake operating state.The output from the 16-knot brake-operating state sensor corresponds to the 7-knot brake-operating state sensor, and it also corresponds to the parking brake operating state. Shock absorber control according to claim 2 or 3, characterized in that the output from the parking brake operating state sensor that generates the output corresponds to the parking brake person. method.