JPH03186418A - Damping force control device - Google Patents

Abstract

PURPOSE:To contrive reduction of processing time and improvement of operation responsiveness with a control routine forced to serve as a discriminating routine and also simplification or the like of constitution to be attempted, by performing a control of damping force not by calculation but by indexing a stored data map. CONSTITUTION:Damping force of a shock absorber (a) is changed by a changing means (b). A condition of a vehicle is detected by an input means (c), while the changing means (b) is controlled by a control means (d) being based on an input signal of this means (c). In the control means (d), a data map (e) of optimum damping force, corresponding to the input signal, is stored in a memory part (f). Further in a control part (g), the optimum damping force, corresponding to the input signal, is indexed by the stored data map (e) simultaneously with a select signal output in accordance with an indexing result of this data map (e). Thus by performing a control of the damping force not by calculation but by indexing the stored data map, processing time is reduced with a control routine serving as a discriminating routine while attaining simplification or the like of constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a damping force control device for controlling the damping force characteristics of a shock absorber provided between sprung and unsprung parts of a vehicle.

(Prior Art) Conventionally, as a damping force control device, for example,
The one described in Japanese Patent No. 181908 is known.

This damping force control device includes an acceleration detection means for detecting acceleration, a damping force changing means for changing the damping force of the shock absorber, and a control means for controlling the operation of the damping force changing means according to the acceleration. Optimum damping force control is performed accordingly.

(Problem to be Solved by the Invention) However, in such a conventional damping force control device, the value required for control is determined by a mathematical formula based on the signal from the acceleration detection means, and the value and the set value are calculated. Since the structure was designed to determine the relationship between In addition, there is a problem in that the calculation routine becomes larger, resulting in an increase in program capacity and calculation processing time, resulting in a decrease in control responsiveness.

The present invention was made by focusing on such problems,
It is an object of the present invention to provide a damping force control device that can simplify the configuration, reduce the size, and reduce costs, as well as improve control responsiveness.

(Means for Solving the Problem) In order to achieve the above-mentioned object, the damping force control device of the present invention employs the means described below.
This will be explained using the complaint correspondence diagram shown in the figure.

The damping force changing means capable of switching the damping force range of the shock absorber a into a plurality of stages includes an input means C for detecting the vehicle condition, and a switching signal to the damping force changing means based on the input signal from the input means C. A control means d for outputting, a storage section f provided in the control means d and storing a data map e indicating the optimum damping force range corresponding to the value of the input signal, and a data map e of the storage section f to determine the actual input. A control section 9 is provided that indexes the optimum damping force range corresponding to the signal and outputs a switching signal based on the index result.

Further, in the apparatus according to the second aspect of the present invention, the number of data maps e stored in the storage section f is at least equal to the number of switchable stages of the damping force changing means.

Furthermore, when outputting the switching signal, the control section 9 arranges the data map e in such a way that the data map e that corresponds to the switching stage of the damping force changing means is placed at the forefront in the index order of the control section 9. Performs rearrangement control to rearrange the array.

(Function) The function of the present invention will be explained. In addition, the symbols in the explanation are
This corresponds to Figure 1.

In the present invention, the control section 9 refers to a predetermined data map e in the storage section f, indexes the optimum damping force range corresponding to the actual input signal based on this data map e, and outputs a switching signal based on the index result. Output. Based on this switching signal, the damping force changing means switches to the optimum damping force range.

When performing such control, in the invention set forth in claim 1.2, the data map e is provided at least in the same number as the number of switchable stages of the damping force changing means, and in the invention set forth in claim 3, When the section 9 outputs the switching signal, the data map e corresponding to the current switching stage of the damping force changing means
FiB controls the sorting control for sorting the distribution 11 of the data map e so that it is in the front row in the index order of the control unit 9.
I try to do it at q.

Therefore, when indexing the data map e, the index starts from the damping force stage of the current damping force changing means. The time required to reach the data map e is omitted, and the time required to index the data map e is shortened.

(Example) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, the configuration of the embodiment will be explained. In this embodiment, an M shock absorber whose damping force characteristics can be switched in eight steps will be described as an example.

FIG. 2 is an overall diagram showing a damping force control device according to an embodiment of the present invention, in which 1 is a variable damping force type shock absorber, 2 is a pulse motor, 3 is a vertical acceleration sensor, 4 is a load sensor, 6 indicates a controller.

The shock absorber 1 has a damping force changing means 7 such as an adjuster provided in the piston rod that rotates to the expansion side.

It is configured so that the overwhelming damping force range can be changed simultaneously in multiple stages from a low range to a high range, such as the one described in the specification and drawings of Japanese Patent Application No. 1-222631 filed by the applicant of the present application. (In the case of this application, the damping force can be changed steplessly). For detailed structure, please refer to the specification and drawings of the above-mentioned application.

The pulse motor 2 operates the damping force changing means 1 of the shock absorber 1, and this pulse motor 2 changes its position in 8 steps. Changes in 8 levels from non-zero to high range.

The acceleration sensor 3 outputs an electric signal corresponding to the vertical acceleration of the sprung body, and is attached to the sprung vehicle body.

The load sensor 4 is provided as a relative speed measuring means for measuring the relative speed between the sprung mass and the unsprung mass. Detects the input load and outputs an electrical signal according to the load.

The controller 6 outputs a switching signal to the pulse motor 2 based on input signals from the acceleration sensor 3 and the load sensor 4 in order to set the shock absorber 1 to optimal damping force characteristics.

That is, this controller 6 includes an interface circuit 61 that inputs signals from both sensors 3.4, an A/D conversion circuit 62 that converts input analog signals into digital signals,
A memory circuit 63 as a storage section (a CPU 64 as a control section that performs control such as index 1 judgment based on the stored data map DM (Fig. 3); 2 is provided with a drive circuit (control section) 65 that outputs a switching signal.

Here, the data map DM stored in the memory circuit 63 will be explained.

As shown in FIG. 3, eight data maps DM are stored in order to switch and control the damping force range of the damping force changing means 7 into eight levels.

As an example of this, FIG. 4 shows a data map DM5 of the fifth damping force range. As shown in this figure, the data map DM shows the stages of the damping force range of the damping force changing means 7 at the upper left corner, which is the intersection of the upper column and the left column (in the figure, the 5th level is shown). ), the upper column shows the value of the vertical velocity data A' obtained from the vertical acceleration data A input from the vertical acceleration sensor 3, and the left column shows the load data input from the load sensor 4 [Spring mass - Unsprung mass] The value of D (corresponding to the relative speed) is shown, and in each square, the optimum damping force (switching position of pulse motor 2) corresponding to the value of vertical speed data A' and load data D is shown. .

Note that the number in each square indicates the optimum range of the damping force range. That is, FIG. 5 shows the damping force characteristics of the shock absorber 1 with respect to the piston speed. As shown in this figure, by changing the damping force changing means 7, the shock absorber 1 can achieve
The damping force range can be switched in eight steps within the damping force range with the characteristics shown in (2).

Next, the control contents of this controller 6 will be explained based on the flowchart shown in FIG.

In step +0+, it is determined whether this operation flow is the first time. Then, if it is the -th time, step 10
If it is the second time or later, proceed to step 103.

In step 102, initial settings are performed. That is, the signs of the load and acceleration A are set to 10, and the data map (
)M to the first stage ■ data map DM, so that it is in the front row DM,, DM 2, DM 3
The data map DM is arranged and read in the order of . This data map DM is called from the so-called ROM part to the 8AM part in the memory circuit 63, and rearranged at this time.

Next, in step 103, the load signal, which is an analog electrical signal input from the load sensor 4, is converted into a digital signal. Then, in the following step 104, the load data D is
65.

Further, in step 105, the acceleration signal, which is an analog electrical signal inputted from the vertical acceleration sensor 3, is converted into a digital signal. Then, in the following step 106, the acceleration data A is read into the CPU 65, and the process proceeds to step 107.

In step 107, the switching stage of the pulse motor 2 is determined according to the value of the vertical speed data A' obtained from the load data D and the vertical acceleration data A, based on the data map DM of the front row (data map o M l in the -th flow). (=optimum damping force range). That is, in this case, first,
Refer to the data map DM in the front row that corresponds to the switching stage of the damping force changing means 7, and then, in that data map DM, select the switching stage (=optimum damping force range) corresponding to the values of both data D and A'. ).

In the following step 108, a switching signal is output from the drive circuit 65 to the pulse motor 2 according to the index result in step 107.

In the following step 109, the stop position of the pulse motor 2 (
The data map DM corresponding to the number of switching stages of the damping force changing means 7) is in the front row, and next to this data map DM is the adjacent data map on the high damping side, then the adjacent data map on the low damping side, and then the next data map. , the data map that is two adjacent to the high attenuation side is rearranged, and then the data map that is two adjacent to the low attenuation side is rearranged. Then, start with data map DM, then data map DM.
a, then data map DM, then data map D
M? , and then the data map DM3.

The controller 6 repeats the above process.

Therefore, in step 107 during the next operation flow, since the data map DM to be indexed is in the front row, the time required to reach the data map DM corresponding to the switching position is omitted, as in the case where no sorting is performed. can do.

As explained above, in the damping force control device of this embodiment, the memory circuit 63
Since the optimum damping force is set by indexing the data map DM stored in the controller 6, the configuration of the controller 6 can be simplified, thereby reducing costs. Since only indexing is required, control responsiveness can be increased.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment. For example, in the embodiments, damping force characteristics may be switched in multiple stages. For example, the configuration is not limited to that shown in this embodiment.

Further, in the embodiment, an example was shown in which the damping force range was switched to eight stages by the damping force changing means, but the number of switching stages may be changed to any number of stages as long as it is plural.

(Effects of the Invention) As explained above, in the damping force control device of the present invention, the damping force control is performed by indexing the data map stored in the storage unit instead of by calculation. This has the effect of simplifying the configuration and reducing costs.At the same time, since the control routine is a discrimination routine, the processing time can be shortened, which improves the operational response. This has the effect of improving sexual performance.

Further, in the apparatus according to the second aspect of the present invention, by providing at least the same number of data maps as the number of switchable stages of the damping force changing means, it is possible to suppress segmentation of the data map, and it is possible to suppress complication of control.

Furthermore, in the apparatus according to claim 3, when the control section outputs the switching signal, the data map is arranged so that the data map corresponding to the switching stage of the damping force changing means is at the forefront in the index order of the control section. Since the rearrangement control is performed to rearrange the data map, the time required for indexing the data map is shortened, and the effect of improving operational responsiveness can be obtained.

[Brief explanation of drawings]

Fig. 1 is a diagram corresponding to the claims of the present invention, Fig. 2 is an overall diagram showing an embodiment of the damping force control device of the present invention, Fig. 3 is a conceptual diagram showing a data map, and Fig. 4 is a diagram for normal use of the fifth stage. FIG. 5 is a diagram showing the damping force characteristics of the shock absorber, and FIG. 6 is a flowchart showing the operation flow of the controller. ...Buffer...Damping force changing means...Input means...Control means...-Data map...Recording section...Control section

Claims (1)

[Claims] 1) damping force changing means capable of switching the damping force range of the shock absorber into multiple stages; input means for detecting vehicle conditions; and damping force changing means based on an input signal from the input means. A control means for outputting a switching signal; a storage section provided in the control means and storing a data map indicating an optimum damping force range corresponding to the value of the input signal; A damping force control device comprising: a control unit that indexes an optimum damping force range corresponding to the index and outputs a switching signal based on the index result. 2) The damping force control device according to claim 1, wherein the number of data maps stored in the storage section is at least the same as the number of switchable stages of the damping force changing means. 3) When outputting a switching signal, the control section arranges the data maps so that the data map corresponding to the switching stage of the damping force changing means is at the forefront in the index order of the control section. 3. The damping force control device according to claim 1, wherein the damping force control device performs rearrangement control to rearrange the damping force.