Suspension system for automotive vehicle

Claim 2

A suspension system as claimed in claim 1, wherein the correcting condition to be corrected by the correction means is so set as to lower a vehicle height of the automotive vehicle body by forcibly discharging the operating fluid from the cylinder unit.

Claim 3

A suspension system as claimed in claim 1, wherein the cornering of the automotive vehicle body is detected by a steered angle of a steering wheel.

Claim 4

A suspension system as claimed in claim 1, wherein the cornering of the automotive vehicle body is detected by a difference in inner pressure between a left-hand cylinder unit and a right-hand cylinder unit.

Claim 5

A suspension system as claimed in claim 1, wherein the cornering of the automotive vehicle body is detected by a magnitude of transverse acceleration acting upon the automotive vehicle body.

Claim 6

A suspension system as claimed in claim 1, wherein the cornering of the automotive vehicle body is detected by a difference in stroke amount between a left-hand cylinder unit and a right-hand cylinder unit.

Claim 7

A suspension system as claimed in claim 1, wherein: plural cornering detecting means are provided; and the automotive vehicle body is determined as cornering when either one of the plural cornering detecting means detects the cornering of the automotive vehicle body.

Claim 8

A suspension system as claimed in claim 1, wherein correction by the correction means is executed when a steered angle of a steering wheel is nearly zero.

Claim 9

A suspension system as claimed in claim 8, wherein the correction by the correction means is executed at the time when the steered angle thereof reaches approximately zero after the control has been suspended by the suspension means.

Claim 10

A suspension system as claimed in claim 1, wherein the correction by the correction means is executed when a transverse acceleration acting upon the automotive vehicle body is approximately zero.

Claim 11

A suspension system as claimed in claim 10, wherein the correction by the correction means is executed at the time when the transverse acceleration reaches approximately zero after the control has been suspended by the suspension means.

Claim 12

A suspension system as claimed in claim 2, wherein: the supply-discharge means comprises a supply control valve and a discharge control valve, which are controllable separately and independently from each other; and the discharge of the operating fluid for lowering the vehicle height thereof is performed by closing the supply control valve and opening the discharge control valve.

Claim 13

A suspension system as claimed in claim 12, wherein the discharge control valve assumes its maximum opening angle when the vehicle height thereof is lowered.

Claim 14

A suspension system as claimed in claim 2, further comprising inner pressure retaining means for regulating an inner pressure within the cylinder unit so as to reach a value equal to or greater than a predetermined value when the vehicle height thereof is lowered.

Claim 15

A suspension system as claimed in claim 2, wherein the automotive vehicle body is determined as cornering when a difference in inner pressure between a left-hand cylinder unit and a right-hand cylinder unit is equal to or greater than a predetermined value.

Claim 16

A suspension system as claimed in claim 15, wherein the automotive vehicle body is determined as cornering when at least one of two conditions is met, the two conditions comprising: a first condition being a difference in inner pressure between the left-hand cylinder unit and the right-hand cylinder unit on the front side of the automotive vehicle body; and a second condition being a difference in inner pressure between the left-hand cylinder unit and the right-hand cylinder unit on the rear side thereof.

Claim 17

A suspension system as claimed in claim 2, wherein the correction by the correction means is executed at the time when the steered angle thereof reaches approximately zero after the control has been suspended by the suspension means.

Claim 18

A suspension system as claimed in claim 2, wherein the correction by the correction means is executed at the time when the transverse acceleration acting upon the automotive vehicle body reaches approximately zero after the control has been suspended by the suspension means.

Claim 19

A suspension system for an automotive vehicle, comprising: a cylinder unit interposed between a sprang weight and an unsprung weight for each wheel; a supply control valve for supplying the operating fluid to the cylinder unit; a discharge control valve for discharging the operating fluid from the cylinder unit; supply-discharge control means for controlling the supply control valve and the discharge control valve under a predetermined condition; incident detecting means for detecting occurrence of an incident which impedes normal implementation of control by the supply-discharge control means; decision means for deciding to determine if the incident is in a first incident mode or in a second incident mode in response to output from the incident detecting means, the first incident mode being to suspend control by the supply-discharge control means in a state in which a vehicle height of an automotive vehicle body is lowered by discharging the operating fluid within the cylinder unit, and the second incident mode being to suspend the control by the supply-discharge control means by maintaining a current vehicle height thereof; execution means for executing the incident mode decided by the decision means; differential pressure detecting means for detecting a difference in inner pressure between a left-hand cylinder unit and a right-hand cylinder unit; and correction means for allowing the execution means to execute the first incident mode prior to a decision by the decision means, when the difference in inner pressure equal to or greater than a predetermined value is detected by the differential pressure detecting means.

Claim 20

A suspension system as claimed in claim 19, wherein the first incident mode is executed by closing the supply control valve and opening the discharge control valve.

Claim 21

A suspension system as claimed in claim 19, wherein the second incident mode is executed by closing both of the supply control valve and the discharge control valve.

Claim 22

A suspension system as claimed in claim 19, wherein: each of the supply control valve and the discharge control valve is of electromagnetic type; the supply control valve is of such a type as being constantly closed yet opened when excited; and supply of a power source to the supply control valve is forcibly shut off when an incident is detected by the incident detecting means.

Claim 23

A suspension system as claimed in claim 22, wherein the power source is so disposed as to be constantly supplied to the discharge control valve from a battery power source.

Claim 24

A suspension system as claimed in claim 23, wherein: the supply-discharge control means comprises a first control section and a second control section, the first control section being for implementing control to open or close the supply control valve and the discharge control valve, and the second control section being for implementing control to open or close the discharge control valve; the power source is constantly supplied to the second control section from the battery power source; and the second control section is so disposed as to open the discharge control valve when an incident is decided as the first incident mode by the decision means due to occurrence of the incident in the first control section.

Claim 25

A suspension system for an automotive vehicle, comprising; a cylinder unit interposed between a sprang weight and a support for each wheel; a pump for converting a low pressure operating fluid within a reservoir tank into a high pressure operating fluid; a high pressure line for supplying the high pressure operating fluid to each of cylinder units by the pump; a low pressure line for returning the operating fluid within each of the cylinder units to the reservoir tank; a supply control valve connected to the high pressure line, which is of an electromagnetic type capable of separately and independently supplying the operating fluid to each of the cylinder units; a discharge control valve connected to the low pressure line, which is of an electromagnetic type capable of separately and independently discharging the operating fluid from each of the cylinder units; supply-discharge control means for controlling opening and closing of the supply control valve and the discharge control valve under a predetermined condition; incident detecting means for detecting occurrence of an incident which impedes normal implementation of control by the supply-discharge control means; decision means for deciding to determine if the incident detected by the incident detecting means is in a first incident mode or in a second incident mode, the first incident mode being to suspend control by the supply-discharge control means in a state in which a vehicle height of an automotive vehicle body is lowered by discharging the operating fluid within the cylinder unit, and the second incident mode being to suspend the control by the supply-discharge control means by maintaining a current vehicle height thereof; execution means for executing the incident mode decided by the decision means; differential pressure detecting means for detecting a difference in inner pressure between a left-hand cylinder unit and a right-hand cylinder unit; correction means for allowing the execution means to execute the first incident mode prior to a decision by the decision means, when the difference in inner pressure equal to or greater than a predetermined value is detected by the differential pressure detecting means; and a fail valve for forcibly releasing the high pressure line to the reservoir tank when the incident is detected by the incident detecting means.

Claim 26

A suspension system as claimed in claim 25, further comprising a valve unit for preventing the inner pressure within the cylinder unit from lowering below a predetermined value by regulating the discharge of the operating fluid from the cylinder unit.

Claim 27

A suspension system as claimed in claim 25, wherein a gas spring is separately and independently connected to each of the cylinder units.

Claim 28

A suspension system as claimed in claim 27, wherein an orifice is interposed between each of the cylinder units and the respective gas spring.

Claim 29

A suspension system as claimed in claim 25, wherein the differential pressure detecting means comprises pressure detecting means for detecting an inner pressure within each of the cylinder units separately and independently from each other, which is so arranged as to generate output to the correction means when the difference between the inner pressures detected by the pressure detecting means for the left-hand cylinder unit and the right-hand cylinder unit on the front side is equal to or greater than a predetermined value or when the difference between the inner pressure detected by the pressure detecting means for the left-hand cylinder unit and the right-hand cylinder unit on the rear side is equal to or greater than a predetermined value.

Claim 30

A suspension system as claimed in claim 26, wherein a valve unit for retaining the inner pressure is closed when pressure within the high pressure line works as a pilot pressure and when the pressure within the high pressure line is equal to or smaller than a predetermined value.