JPH0572511U - Vehicle suspension - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a vehicle suspension system capable of preventing generation of radio noise and reduction of actuator torque without increasing the size of a controller. A damping characteristic changing means c provided in the shock absorber a for changing a damping characteristic of the shock absorber a by driving an actuator b, a vehicle behavior detecting means d for detecting a vehicle behavior, and a vehicle behavior detecting means d. Of the damping characteristic control unit e which outputs a signal indicating the driving direction of the actuator b by obtaining the optimum damping characteristic corresponding to the vehicle behavior, and the actuator b receiving the signal from the damping characteristic control unit e. And a controller h having a judgment control circuit section f for judging the driving of the actuator and a driving circuit section g for controlling the current for driving the actuator b based on the judgment of the judgment control circuit section f. In the suspension device, the judgment control circuit section f and the drive circuit section g
And are provided in the vicinity of each actuator b separately from the damping characteristic control unit e.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vehicle suspension system that optimally controls the damping characteristics of a shock absorber.

[0002]

[Prior Art]

 Conventionally, as a vehicle suspension device for controlling the damping characteristic of a shock absorber, for example, one disclosed in Japanese Patent Laid-Open No. 61-215106 is known.

In this conventional vehicle suspension system, an actuator for rotationally driving a damping characteristic changing means for changing the damping characteristic is arranged at the upper end of the piston rod, and a drive circuit for driving the actuator and a controller for sending a signal to the drive circuit are respectively provided. It was placed in the passenger compartment and had a harness connected between them.

[0004]

[Problems to be solved by the device]

 However, the conventional device described above has a problem in that wiring is complicated in the vehicle body because the controller, the drive circuit, and the actuators are connected by harnesses. It should be noted that by integrating the controller and the drive circuit, the harness connecting them can be omitted, but this would make it difficult to secure the installation space for the controller because the controller would become larger. Another problem arises.

Further, since the harness portion connecting the drive circuit and each actuator becomes long, radio noise is generated at the portion and actuator torque is reduced due to voltage drop due to wiring resistance. was there.

The present invention has been made in view of the above problems, and provides a vehicle suspension device capable of preventing generation of radio noise and reduction of actuator torque without increasing the size of a controller. It is an object.

[0007]

[Means for Solving the Problems]

 Therefore, in the present invention, the judgment control circuit section and the drive circuit section are provided in the vicinity of each actuator separately from the damping characteristic control section to achieve the above object.

That is, the vehicle suspension system of the present invention is provided on the shock absorber a and a shock absorber a interposed between the vehicle body side and each wheel side, as shown in the claim correspondence diagram of FIG. , A damping characteristic changing means c for changing the damping characteristic of the shock absorber a by driving the actuator b, a vehicle behavior detecting means d for detecting the vehicle behavior, and a signal from the vehicle behavior detecting means d for receiving the vehicle behavior and responding to the vehicle behavior. A damping characteristic control unit e which outputs a signal instructing the driving direction of the actuator b by obtaining the optimum damping characteristic, and a determination control circuit which receives the signal from the damping characteristic control unit e and determines the driving of the actuator b. A controller having a section f and a drive circuit section g for controlling a current for driving the actuator b based on the judgment of the judgment control circuit section f. In the vehicle suspension system including h and h, the judgment control circuit section f and the drive circuit section g are provided in the vicinity of each actuator b as separate bodies from the damping characteristic control section e.

[0009]

[Action]

 Since the vehicle suspension system of the present invention is configured as described above, the damping characteristic control unit e receives the signal from the vehicle behavior detecting means d to obtain the optimum damping characteristic according to the vehicle behavior to determine the actuator b. A signal indicating the driving direction is output to the determination control circuit unit f. Then, the judgment control circuit section f judges whether to drive the actuator b according to the driving position of the actuator b at that time, and the driving circuit section g drives the actuator b based on the judgment of the judgment control circuit section f. The control of the electric current to be performed is performed, whereby each shock absorber a is controlled to have an optimum damping characteristic.

Further, in the present invention, since the judgment control circuit section f and the drive circuit section g are provided in the vicinity of each actuator b as a separate body from the damping characteristic control section e, the drive circuit section g It is possible to shorten the harness that connects between the actuator and each actuator b, thereby preventing generation of radio noise and reduction in actuator torque.

[0011]

【Example】

 Embodiments of the present invention will be described with reference to the drawings. First Example First, the configuration will be described.

FIG. 2 is a structural explanatory view showing a vehicle suspension system according to an embodiment of the present invention, in which four shock absorbers SA are provided between a vehicle body and four wheels, and a steering ST is provided. Is provided with a steering angle sensor 5a for detecting the steering angle. A vertical acceleration sensor (hereinafter referred to as vertical G sensor) 1 for detecting vertical acceleration is provided on the vehicle body near each shock absorber SA. Further, each shock absorber SA, which will be described in detail later, has a structure in which the damping characteristic can be changed by driving the pulse motor (actuator) 3.

FIG. 3 is a system block diagram showing the above-mentioned configuration. As shown in this figure, a controller 4 for controlling the damping characteristic of each shock absorber SA is provided. It is composed of a control section 4a, a judgment control circuit section 4b, and a drive circuit section 4c.

The damping characteristic control unit 4a receives signals from vehicle behavior detecting means such as the vehicle speed sensor 5b and the brake sensor 5c in addition to the vertical G sensor 1, the steering angle sensor 5a, and responds to the vehicle behavior. This is a part that outputs a signal that indicates the driving direction of the pulse motor 3 in order to obtain the optimum damping characteristics, and is a so-called microcomputer provided near the driver's seat of the vehicle body as shown in the configuration explanatory view of FIG. An input circuit 41 configured to input signals from the sensors 1, 5a, 5b, 5c and convert the signals into control signals, and a shock absorber SA based on vehicle behavior obtained through the input circuit 41. The calculation circuit 42 calculates the optimum damping characteristic and outputs a signal indicating the driving direction of the pulse motor 3 toward this damping characteristic.

The determination control circuit unit 4b is a unit that receives a signal from the attenuation characteristic control unit 4a and determines whether to drive the pulse motor 3, and the drive circuit unit 4c is the determination control circuit unit. 4b is a portion that controls a current to drive the pulse motor 3 based on the determination of 4b. In this embodiment, both circuit portions 4b and 4c are provided integrally with each pulse motor 3. A harness 43 connects between each determination control circuit unit 4b and the arithmetic circuit 42 of the damping characteristic control unit 4a.

That is, FIG. 14 is an enlarged sectional view showing a portion of the pulse motor 3, and as shown in the figure, the pulse motor 3 includes a housing 3a, an output shaft 3b, a rotor core 3c and a rotor magnet 3d. , A stator coil 3e and a stator core 3f. In addition, 3g and 3h are bearings. The judgment control circuit portion 4b and the drive circuit portion 4c are housed in the upper end portion of the housing 3a, and the drive circuit portion 4c and the stator coil 3e are connected by the harness 3k in the housing 3a. Has been done.

Next, the configuration of the shock absorber SA will be described with reference to FIG. This shock absorber SA includes a cylinder 30, a piston 31 defining the cylinder 30 into an upper chamber A and a lower chamber B, an outer cylinder 33 having a reservoir chamber 32 formed on the outer periphery of the cylinder 30, a lower chamber B and a reservoir. A base 34 defining a chamber 32, a guide member 35 for guiding the sliding of the piston rod 7 connected to the piston 31, a suspension spring 36 interposed between the outer cylinder 33 and the vehicle body, and a bumper bar 37. It has and. The pulse motor 3 is attached to the upper end of the piston rod 32 via a bracket 38.

Next, FIG. 5 is an enlarged cross-sectional view showing a portion of the piston 31. As shown in this figure, the piston 31 has through holes 31a and 31b formed therein, and An expansion side damping valve 12 and a compression side damping valve 20 that open and close the holes 31a and 31b, respectively, are provided. In addition, in the axial center portion of the piston rod 7 penetrating the piston 31, a flow path that communicates the upper chamber A and the lower chamber B by bypassing the through holes 31a and 31b (the second expansion side flow described later) A communication hole 39 is formed for forming the passage E, the extension side third flow passage F, the bypass flow passage G, and the pressure side second flow passage J), and the flow of the flow passage is formed in the communication hole 39. An adjuster 40 for changing the road cross-sectional area is rotatably provided. Further, on the outer peripheral portion of the piston rod 7, there are provided an extension side check valve 17 and a pressure side check valve 22 which allow and block the flow of the flow passage formed by the communication hole according to the flow direction of the fluid. .. The adjuster 40 is rotated by the pulse motor 3 via the control rod 70 (see FIG. 4). The piston rod 7 is formed with a first port 21, a second port 13, a third port 18, a fourth port 14, and a fifth port 16 in order from the top.

On the other hand, in the adjuster 40, the hollow portion 19 is formed, the first lateral hole 24 and the second lateral hole 25 that communicate the inside and the outside are formed, and further, the vertical groove 23 is formed in the outer peripheral portion. There is.

Therefore, between the upper chamber A and the lower chamber B, the inside of the expansion side damping valve 12 is opened by passing through the through hole 31b as a flow path through which the fluid can flow in the extension stroke. The expansion-side first flow path D reaching B 2 and the expansion-side damping valve 12 opening on the outer peripheral side via the second port 13, the vertical groove 23, and the fourth port 14 to reach the lower chamber B. The second flow passage E, the second port 13, the vertical groove 23, and the fifth port 16, the expansion side check valve 17 is opened to reach the lower chamber B. There are four flow paths of the bypass flow path G reaching the lower chamber B via 18, the second lateral hole 25, and the hollow portion 19. In addition, the pressure side first flow path H that opens the pressure side damping valve 20 through the through hole 31a, the hollow portion 19, the first lateral hole 24, and the first port 21 are used as the flow path through which the fluid can flow in the pressure stroke. After passing through the pressure side check valve 22, the pressure side second flow path J reaching the upper chamber A and the bypass flow reaching the upper chamber A via the hollow portion 19, the second lateral hole 25 and the third port 18 are provided. There are three channels, G and G.

That is, the shock absorber SA is configured such that the damping characteristics can be changed in multiple stages with the characteristics shown in FIG. 5 on both the extension side and the compression side by rotating the adjuster 40. That is, as shown in FIG. 7, when the adjuster 40 is rotated in the counterclockwise direction from the state in which both the expansion side and the compression side are soft (hereinafter referred to as the soft region SS), the damping characteristics only in the expansion side have multiple stages. It can be changed and the compression side becomes a region fixed to the low damping characteristic (hereinafter referred to as the extension side hard region HS). Conversely, when the adjuster 40 is rotated in the clockwise direction, only the compression side changes the damping characteristic in multiple stages. The structure is such that it is possible and the extension side is a region fixed to the low damping characteristic (hereinafter referred to as the compression side hard region SH).

By the way, in FIG. 7, the KK cross section, the MM cross section, and the NN cross section in FIG. 10 and the damping force characteristics at each position are shown in FIGS.

Next, the attenuation characteristic control of the arithmetic circuit 42 will be described. In the present invention, this damping characteristic control is not the main point, so it will be described briefly. That is, the arithmetic circuit 42 first calculates the sprung vertical velocity by integrating the vertical acceleration obtained from the vertical G sensor 1. Then, the damping characteristic is set in proportion to the direction and speed of the sprung vertical speed. That is, if the sprung vertical velocity is positive (upward), it is defined as the extension side hard region HS, and if negative (downward), it is determined as the compression side hard characteristic SH. It is controlled to become. In this control, based on the input from the vehicle speed sensor 5b, the higher the vehicle speed, the higher the damping characteristic becomes.

Further, based on the inputs from the steering angle sensor 5a and the vehicle speed sensor 5b, when steering is performed at a predetermined vehicle speed or more and at a predetermined change rate or more, it is determined that a roll occurs in the vehicle body. The shock absorber SA on the side where the vehicle body sinks is set to the compression side hard area SH, while the shock absorber SA on the side where the vehicle body floats is controlled to the extension side hard area HS.

Further, based on the input from the vehicle speed sensor 5b, it is determined that a scut occurs in the vehicle body at the time of a sudden start, and the shock absorber SA on the rear wheel side where the vehicle body sinks is set as the pressure side hard area SH. On the other hand, the shock absorber SA on the front wheel side where the vehicle body floats is controlled to the extension side hard area HS.

Further, based on the input from the brake sensor 5c, it is determined that a dive occurs in the vehicle body during the braking operation, and the shock absorber SA on the front wheel side where the vehicle body sinks is set as the pressure side hard area SH. On the other hand, the shock absorber SA on the rear wheel side where the vehicle body floats is controlled to the extension side hard area HS.

When the optimum damping characteristic of each shock absorber SA is calculated as described above, a signal instructing the driving direction of the pulse motor 3 toward this damping characteristic is output from the arithmetic circuit 42 to each pulse via the harness 43. It is output to the judgment control circuit section 4b of the motor 3. Then, the judgment control circuit unit 4b judges whether to drive the pulse motor 3 according to the step position of the pulse motor 3 at that time, and the drive circuit unit 4c controls the current for driving the pulse motor 3 based on this judgment. Is performed.

As described above, in the vehicle suspension system of this embodiment, the judgment control circuit unit 4b and the drive circuit unit 4c are provided separately from the damping characteristic control unit 4a, so that the vehicle interior can be installed. Wiring in the vehicle body can be reduced without increasing the size of the controller part that can be eclipsed, and the judgment control circuit portion 4b and the drive circuit portion 4c are integrally provided in the housing 3a of each pulse motor 3. As a result, the harness 3k that connects the drive circuit unit 4c and the pulse motor 3 is shortened, and it is possible to prevent generation of radio noise and reduction in actuator torque. ..

Second Embodiment Next, a second embodiment of the present invention will be described. In explaining this embodiment, only the differences from the first embodiment will be described. The same reference numerals as those used in the first embodiment indicate the same objects.

In this embodiment, the judgment control circuit section 4b and the drive circuit section 4c are integrally provided on the lower end side of the pulse motor 300.

That is, FIG. 15 is an enlarged cross-sectional view showing a portion of the pulse motor 300 used in this embodiment. As shown in this drawing, a bracket is provided on the lower surface side of the housing 3 m of the pulse motor 300. A ring-shaped lower housing portion 3n is integrally formed by utilizing an annular gap which is a dead space between the output shaft 3b and the output shaft 3b, and the judgment control circuit portion 4b and the judgment control circuit portion 4b are formed in the lower housing portion 3n. The drive circuit section 4c is housed therein. The drive circuit section 4b and the stator coil 3e are connected by a harness 3k.

Therefore, in this embodiment, as compared with the pulse motor 3 of the first embodiment, since the pulse motor 300 is not raised upward, the stroke of the shock absorber SA is sacrificed even in a vehicle with a low vehicle height. It has the feature that it can be easily installed in a vehicle without doing so.

Although the embodiment has been described above, the specific configuration is not limited to this embodiment, and even if there is a design change or the like within a range not departing from the gist of the invention, the invention is included in the invention. ..

For example, in the embodiment, as the vehicle behavior detecting means, the vertical G sensor, the steering angle sensor, the vehicle speed sensor, and the brake sensor are shown, but if the one that detects the control factor related to the vehicle behavior is sprung- Other sensors such as a means for detecting the relative speed between the unsprung parts (a load sensor, a damping force sensor), a sensor for detecting the lateral acceleration of the vehicle, a sensor for detecting the longitudinal acceleration, or the like may be used.

Further, in the embodiment, the judgment control circuit unit and the drive circuit unit are integrally provided in the housing of each pulse motor. However, in the vicinity of each pulse motor, they are provided separately from the pulse motor. The two may be connected by a connector.

[0036]

[Effect of the device]

 As described above, in the vehicle suspension system of the present invention, in the controller, the judgment control circuit section and the drive circuit section are provided separately from the damping characteristic control section on each actuator side. By doing so, it is possible to reduce the wiring in the vehicle body without increasing the size of the controller part provided in the passenger compartment, and to provide the judgment control circuit part and the drive circuit part in the vicinity of each actuator. Since the harness that connects the drive circuit unit and the actuator can be shortened, it is possible to prevent the generation of radio noise and the reduction of the actuator torque.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a claim showing a vehicle suspension device of the present invention.

FIG. 2 is a structural explanatory view showing a vehicle suspension device of the first embodiment of the present invention.

FIG. 3 is a system block diagram showing the vehicle suspension system of the first embodiment.

FIG. 4 is a sectional view showing a shock absorber applied to the device of the first embodiment.

FIG. 5 is an enlarged sectional view showing a main part of the shock absorber.

FIG. 6 is a damping force characteristic diagram corresponding to the piston speed of the shock absorber.

FIG. 7 is a characteristic diagram of damping characteristics corresponding to the step position of the pulse motor of the shock absorber.

FIG. 8 is a part of the shock absorber shown in FIG.
FIG.

FIG. 9 is an M of FIG. 5 showing a main part of the shock absorber.
FIG.

FIG. 10 is a sectional view taken along line NN of FIG. 5, showing a main part of the shock absorber.

FIG. 11 is a damping force characteristic diagram of the shock absorber when the extension side is hard.

FIG. 12 is a damping force characteristic diagram of the shock absorber in a soft state on the extension side and the compression side.

FIG. 13 is a damping force characteristic diagram of the shock absorber in a pressure side hard state.

FIG. 14 is an enlarged cross-sectional view showing a portion of the pulse motor of the first embodiment device.

FIG. 15 is an enlarged sectional view showing a portion of a pulse motor in the vehicle suspension system of the second embodiment of the present invention.

[Explanation of symbols]

 a shock absorber b actuator c damping characteristic changing means d vehicle behavior detecting means e damping characteristic control section f judgment control circuit section g drive control section h controller

Claims (2)

[Scope of utility model registration request] 1. A shock absorber interposed between a vehicle body side and each wheel side, damping characteristic changing means provided on the shock absorber for changing a damping characteristic of the shock absorber by driving an actuator, and vehicle behavior detection. A vehicle behavior detecting means, a damping characteristic control section that receives a signal from the vehicle behavior detecting means, obtains an optimum damping characteristic according to the vehicle behavior, and outputs a signal indicating a driving direction of an actuator, and the damping characteristic A controller having a determination control circuit unit that receives a signal from the control unit and determines whether to drive the actuator, and a drive circuit unit that controls a current to drive the actuator based on the determination of the determination control circuit unit, In the vehicle suspension system including the above, the determination control circuit unit and the drive circuit unit are provided separately from the damping characteristic control unit. Vehicle suspension system, characterized in that Chueta provided near. 2. The vehicle suspension system according to claim 1, wherein the determination control circuit unit and the drive circuit unit are provided in a housing of each actuator.