Fluid-pressure and analogous brake systems – Speed-controlled – Having a valve system responsive to a wheel lock signal
Reexamination Certificate
2001-07-05
2004-02-10
Lavinder, Jack (Department: 3683)
Fluid-pressure and analogous brake systems
Speed-controlled
Having a valve system responsive to a wheel lock signal
C303S155000
Reexamination Certificate
active
06688705
ABSTRACT:
This application is based on Japanese Patent Application No. 2000-229281 filed Jul. 28, 2000,the contents of which are incorporated hereinto by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates in general to a hydraulic pressure control apparatus, and more particularly to techniques for determining a control value of a pressure control actuator provided in the pressure control apparatus.
2. Discussion of Related Art
JP-A-8-67242 discloses a hydraulic pressure control apparatus including (a) a hydraulic pressure source device provided with a pressure control actuator operable according to a control value, and (b) an actuator control device which includes a control-value determining portion operable to determine the control value of the pressure control actuator, and which controls the pressure control actuator according to the control value determined by the control-value determining portion. In this hydraulic pressure control apparatus, the control value of the pressure control actuator is determined on the basis of an operating force applied to a manually operable brake operating member. Accordingly, an output hydraulic pressure of the hydraulic pressure control apparatus changes immediately in response to a change in the operating force of the brake operating member. Although the hydraulic pressure control apparatus has a high degree of control response, it tends to suffer from control hunting.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a hydraulic pressure control apparatus which has a reduced degree of control hunting, while avoiding deterioration of the control response.
The above object may be achieved according to any one of the following modes of the present invention, each of which is numbered like the appended claims and depends from the other mode or modes, where appropriate, to indicate and clarify possible combinations of elements or technical features. It is to be understood that the present invention is not limited to the technical features or any combinations thereof which will be described for illustrative purpose only. It is to be further understood that a plurality of elements or features included in any one of the following modes of the invention are not necessarily provided all together, and that the invention may be embodied without some of the elements or features described with respect to the same mode.
(1) A hydraulic pressure control apparatus for use with a manually operable operating member, the hydraulic pressure control apparatus comprising:
a hydraulic pressure source device including a pressure control actuator operable according to a control amount, the hydraulic pressure source device being operable to generate an output pressure thereof on the basis of a fluid pressure corresponding to an operating force of the manually operable operating member, and on the basis of a control pressure controlled by the pressure control actuator; and
an actuator control device including a final-control-value determining portion operable to determine a final value of the control amount, the actuator control device controlling the pressure control actuator according to the final value determined by the final-control-value determining portion,
and wherein the final-control-value determining portion determines the final value of the control amount on the basis of at least two provisional control values selected from the group consisting of (a) at least one first provisional control value each of which is determined on the basis of at least one physical quantity including at least one of (i) an operating-state value representative of an operating state of the manually operable operating member and (ii) the output pressure of the hydraulic pressure source device, and (b) at least one second provisional control value each of which is determined on the basis of a combination of physical quantities which includes at least two of the operating-state value, the output pressure and the control pressure controlled by the pressure control actuator.
In the hydraulic pressure control apparatus constructed according to the above mode (1) of the present invention, the hydraulic pressure source device is operated to generate its output pressure on the basis of the fluid pressure corresponding to the operating force of the manually operable operating member, and the control pressure which is controlled by the pressure control actuator according to the control amount controlled by the actuator control device. The actuator control device is arranged to control the pressure control actuator, according to a predetermined rule, that is, so as to establish a predetermined relationship among the operating force or other operating-state value of the operating member, the control pressure controlled by the pressure control actuator and the output pressure of the hydraulic pressure source device. Therefore, when the two of these three physical quantities are determined, the remaining physical quantity can be determined on the basis of the determined two physical quantities and according to the predetermined relationship. Similarly, when one of the three physical quantities is determined, the remaining two physical quantities can be determined on the basis of the determined one physical quantity and according to the predetermined relationship.
In the present hydraulic pressure control apparatus, the final-control-value determining portion of the actuator control device is arranged to determine the final value of the control amount of the pressure control actuator, on the basis of at least two provisional control values selected from the group consisting of (a) at least one first provisional control value each determined on the basis of at least one physical quantity including at least one of the operating-state value of the manually operable operating member and the output pressure of the hydraulic pressure source device, and (b) at least one second provisional control amount each determined on the basis of two or three of the operating-state value, the output pressure and the control pressure controlled by the pressure control actuator. One of the three physical quantities which have the predetermined relationship as described above is the operating-state value representative of the operating state of the manually operable operating member. The operating-state value used to determine the final value of the control amount for controlling the pressure control actuator may include not only the operating force to be applied to the operating member, but also the operating stroke or amount of the operating member, and may consist of a combination of the operating force and stroke of the operating member when it is operated. Where the hydraulic pressure control device is used for a braking system for an automotive vehicle and includes a brake operating member as the manually operable operating member, at least one of the operating force and stroke of the operating member represents a braking force to be generated by the braking system, which braking force is desired by the vehicle operator.
For instance, a desired value of the control pressure can be determined on the basis of one of the operating-state value and the output pressure and according to the predetermined rule or relationship, so that the control amount for controlling the pressure control actuator to control the actual value of the control pressure can be determined on the basis of the determined desired value of the control amount.
The operating-state value of the operating member can be estimated on the basis of the output pressure of the hydraulic pressure source device and the control pressure controlled by the pressure control actuator. Therefore, the desired value of the control pressure can be determined on the estimated operating-state value, so that the control amount can be determined. Similarly, the output pressure can be estimated on the basis of the operating-state value and the control pressure, so that the control amount can be de
Isono Hiroshi
Mizutani Yasuji
Lavinder Jack
Nguyen Xuan Lan
Oliff & Berridg,e PLC
Toyota Jidosha & Kabushiki Kaisha
LandOfFree
Pressure control apparatus wherein pressure control actuator... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pressure control apparatus wherein pressure control actuator..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pressure control apparatus wherein pressure control actuator... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3352923