JPH04321828A - Damping-force control device for hydraulic shock absorber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping force control device for a hydraulic shock absorber, which adjusts the amount of deflection around a leaf valve as a damping force generating valve and changes the main damping force generated.

0002

[Prior Art] As a damping force adjusting device for a conventional hydraulic shock absorber, the amount of deflection of the peripheral end of a leaf valve, which is a damping force generating valve, is adjusted by applying voltage to a piezoelectric element, and the main damping force generated by the leaf valve is adjusted. The one that changed the
For example, it is proposed in Japanese Patent Application Laid-open No. 13041/1983.

This proposal is based on the idea that when a voltage is applied to a piezoelectric element, which is an electrostrictive member, and the piezoelectric element expands, the expansion force directly controls the amount of deflection of the peripheral end of a leaf valve, which is a damping force generating valve. This adjusts the damping force generated by the leaf valve.

0004

[Problems to be Solved by the Invention] However, such a conventional damping force adjustment device for a hydraulic shock absorber has problems due to the input/output characteristics of the piezoelectric actuator, which is the piezoelectric element, the flow rate with respect to the piston speed, and the nonlinearity of the throttling effect. For the drive voltage actually input to the piezoelectric actuator,
The damping force generated by this drive voltage does not change linearly, and specifically, the damping force changes only slightly even if the adjustment range of the drive voltage is increased, or even if the adjustment range of the drive voltage is decreased. There were problems such as the damping force changing significantly, making it impossible to adjust the damping force with high precision.

The present invention was made in order to solve the above-mentioned conventional problems, and is to correct the nonlinearity of a hydraulic shock absorber having a piezoelectric actuator using a correction circuit having nonlinear characteristics complementary to the nonlinearity of a hydraulic shock absorber. It is an object of the present invention to provide a damping force adjustment device for a hydraulic shock absorber which performs linear correction using an input voltage from a hydraulic shock absorber and which enables linear control of the generated damping force with respect to the input.

[0006]

[Means for Solving the Problems] A damping force control device for a hydraulic shock absorber according to the present invention includes a hydraulic shock absorber having a damping force generating valve in a cylinder that generates a damping force, and a hydraulic shock absorber provided in the hydraulic shock absorber. and a piezoelectric actuator that adjusts the damping force generated by the damping force generating valve, and a nonlinear correction circuit that linearly corrects the nonlinearity of the generated damping force with respect to the input voltage of the piezoelectric actuator. This is what I did.

[0007]

[Operation] The nonlinear correction circuit according to the present invention adjusts the corresponding nonlinear input voltage for correction, which is obtained by referring to the nonlinear data that is the input voltage vs. damping force characteristic of the hydraulic shock absorber, in accordance with the driver input voltage. Output.

Since the non-linear input voltage has the characteristic of linearly compensating the non-linear data, it is possible to adjust the damping force linearly with respect to the driver input voltage.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In Fig. 1, 1 is a hydraulic shock absorber that has a damping force generating valve inside the cylinder, and 2 is a piezoelectric actuator that adjusts the damping force generated by the damping force generating valve.This is an example of a hydraulic shock absorber. Provided on the piston rod side, etc.

Reference numeral 3 denotes a nonlinear correction circuit for linearly correcting the nonlinearity of the damping force generated with respect to the input voltage of the piezoelectric actuator 2.

[0011] Also, in this non-linear correction circuit 3, 4
5 is an analog/digital converter that digitally converts the driver input input to this input section; 6 is the input voltage vs. generated damping of the hydraulic buffer 1; A memory (read-only memory) that stores non-linear data for linearly correcting non-linear characteristics of force, 7 refers to the non-linear characteristics stored in this memory 6, and performs driver input. A processor that obtains input voltage data to the piezoelectric actuator 2 corresponding to the voltage, 8 a digital/analog converter that converts the input voltage data output from the processor 7 into an analog signal, and 9 an output that amplifies the analog output and outputs it. Based on the analog output from the output unit 9, the parts and 10 output the nonlinear high voltage from the high voltage power supply part 11 to the hydraulic buffer 1.
This is the drive unit that supplies the

FIG. 2 is a characteristic diagram showing the input voltage versus damping force characteristics of the piezoelectric actuator 2 of the hydraulic shock absorber 1, and nonlinear data as shown in FIG. 3 for linearly correcting this nonlinear characteristic is stored in the memory 6. is stored in.

The processor 7 also obtains piezoelectric actuator input voltage data corresponding to the driver input voltage with reference to FIG. 3, and outputs the result.

In other words, the non-linear correction circuit 3 converts the driver input voltage input thereto into non-linear data that complements the non-linear operating characteristics of the buffer, and converts this into non-linear data that complements the non-linear operating characteristics of the hydraulic buffer 1. 2, the result is a linear control of the damping force as shown in FIG.

Next, the operation will be explained. First, in order to adjust the damping force of the hydraulic shock absorber 1, a driver input voltage (low voltage) for damping force adjustment is inputted to the non-linear correction circuit 3.

If this driver input voltage is directly input to the hydraulic shock absorber 1, it will exhibit a nonlinear damping force as shown in FIG. 2 as an output.

The input section 4 receives this driver input voltage, performs rectification, amplification, etc., and outputs it as a signal.

Furthermore, the output of this input section 4 is converted into a digital signal by an analog/digital converter 5 and inputted to a processor 7.

The processor 7 refers to the non-linear data as shown in FIG. 3 stored in the memory 6 and obtains the piezoelectric actuator input voltage corresponding to the digital signal as the driver input voltage as input voltage data.

Further, this input voltage data is inputted to the digital/analog converter 8 and converted into analog data, and further output-converted at the output section and inputted to the drive section 10.

The drive section receives a high voltage corresponding to output data from the output section from the high voltage power supply section 11 and inputs it to the piezoelectric actuator 2 of the hydraulic shock absorber 1.

Therefore, the piezoelectric actuator 2 is supplied with a nonlinear input voltage as shown in FIG. 3, which linearly corrects the nonlinearity shown in FIG. 2, and as a result, the driver input voltage vs. attenuation is This makes it possible to realize a hydraulic damping control operation having the characteristics shown in FIG. 4, in which the force is linear.

[0023]

As described above, according to the present invention, there is provided a hydraulic shock absorber having a damping force generating valve in a cylinder that generates damping force, and a hydraulic shock absorber provided in the hydraulic shock absorber that generates a damping force by the damping force generating valve. The driver input voltage is This means that the damping force can be adjusted linearly, and the damping force can be adjusted with high precision.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a damping force control device for a hydraulic shock absorber according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing the piezoelectric actuator input voltage versus damping force characteristic of the hydraulic shock absorber.

FIG. 3 is a characteristic diagram showing the input/output characteristics of nonlinear data stored in the memory in FIG. 1;

FIG. 4 is a characteristic diagram showing driver input voltage versus damping force according to the present invention.

[Explanation of symbols]

1 Hydraulic shock absorber 2 Piezoelectric actuator 3 Non-linear correction circuit

Claims (1)

[Claims] 1. A hydraulic shock absorber having a damping force generation valve in a cylinder that generates a damping force, and a piezoelectric actuator provided in the hydraulic shock absorber to adjust the damping force generated by the damping force generation valve. A damping force control device for a hydraulic shock absorber, comprising: a nonlinear correction circuit that linearly corrects nonlinearity of the generated damping force with respect to an input voltage of the piezoelectric actuator.