DE102015015239A1 - System and method for improving vehicle stability - Google Patents

Abstract

An object of the invention is a method of improving vehicle stability by controlling a pneumatic parking brake circuit device when using said parking brake circuit device for braking, said parking brake circuit device comprising braking means for the wheels of at least two wheel axles of the vehicle said vehicle comprising the following steps: - continuously determining (s410) an air pressure (P) of said pneumatic parking brake circuit device; Activating (s420) the braking by said braking means of said pneumatic parking brake circuit device; Determining (s430) an air pressure value (Px) at which the braking means (BM2a, BM2b) of at least one wheel axle (WA2) of said at least two wheel axles (WA1, WA2) is limited in braking action; Controlling (s440) an air pressure valve unit (260) for the braking means (BM2a, BM2b) of said at least one wheel axle (WA2) such that the braking effect is limited to a predetermined value (Fx) corresponding to said determined air pressure value (Px ) corresponds. The invention also relates to a computer program product with program code (P) for a computer (200; 210) for implementing a method according to the invention. Another object of the invention is a system for improving vehicle stability and a vehicle equipped with this system.

Description

Technical part

An object of the present invention is a method of improving vehicle stability by controlling a pneumatic parking brake circuit device when using said parking brake circuit device for braking. Another object of the invention is a computer program product with program code for a computer for carrying out a method according to the invention. The invention also relates to a system for improving vehicle stability by controlling a pneumatic parking brake circuit device when using said parking brake circuit device for braking and a motor vehicle equipped with such a system.

background

Today's motor vehicles are equipped with a parking brake circuit, which is intended for use with a vehicle at a standstill, for example when the vehicle is parked between operating times or in other situations. In this case, a braking force is exerted by means of a manually operated actuating means, for example a parking brake lever. This parking brake circuit is separate from one or more brake circuits which are employed during the travel of said vehicle and which may be conventional brake circuits for operating the vehicle either by means of a driver-actuated brake pedal or by automatic control systems brake.

It is known that said parking brake circuit is also used in emergencies or other situations where a relatively high braking force is required to reduce the speed of said vehicle. As a result, a vehicle user can use the aforementioned parking brake circuit to exercise an additional braking force in addition to one or more of the said service brake circuits in order to brake the said vehicle more effectively.

However, the use of said parking brake circuit while driving the vehicle is associated with some disadvantages. The parking brake circuit can be used as an emergency brake if the said conventional brake circuits fail or do not provide sufficient braking force to brake the vehicle. It is known that it is difficult for a vehicle user to use the parking brake circuit so that a desired braking force is achieved. Normally only very experienced drivers are able to control said parking brake circuit by means of said parking brake lever and to achieve a strong braking of the vehicle. If the parking brake circuit is not operated correctly, said vehicle may become unstable and rotate about a vertical axis. This can, of course, lead to dangerous situations, not only for the driver and passengers of the vehicle, but also for other vehicles, persons or structures / objects located in the vicinity of the unstable vehicle.

If the parking brake chambers of different wheel axles of the vehicle are not properly adjusted, the vehicle may already become unstable before it reaches an acceptable deceleration. Another disadvantage of today's parking brake circuits is that a required braking force is not provided when all the brake chambers are activated at a certain air pressure of the parking brake circuit, because the air pressure of all the brake chambers should be substantially equal.

Therefore, there is a need to provide a reliable parking brake circuit that enables safe application of braking force while the vehicle is traveling, thus avoiding or reducing instability.

The patent EP 2615003 relates to a parking brake module for a pressure-actuated brake system of a vehicle that is suitable for connecting a trailer.

Summary of the invention

An object of the present invention is to provide a novel and advantageous method for improving vehicle stability.

Another object of the invention is to provide a novel and advantageous system and a novel and advantageous computer program for improving vehicle stability.

Another object of the invention is to provide a method, system and computer program for safely braking a vehicle in an emergency, avoiding an instability condition.

Another object of the invention is to provide a method, system and computer program for improving vehicle stability when braking said vehicle.

Another object of the invention is to provide an alternative method, an alternative method To provide system and an alternative computer program for improving vehicle stability.

Some of these objects are achieved with a method for improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device providing braking means for the wheels of at least two wheel axles of said vehicle according to claim 1. Other objects are achieved by a system according to claim 6. Advantageous embodiments are mentioned in the dependent claims. Substantially the same advantages of method steps of the method according to the invention also apply to the corresponding means of the system according to the invention.

• – kontinuierliche Feststellung eines Luftdrucks der genannten pneumatischen Feststell-Bremskreis-Vorrichtung;
• – Aktivierung der Bremsung durch das genannte Bremsmittel der genannten pneumatischen Feststell-Bremskreis-Vorrichtung;
• – Feststellung eines Luftdruckwerts, bei dem das Bremsmittel mindestens einer Radachse der genannten mindestens zwei Radachsen in seiner Bremswirkung begrenzt ist;
• – Steuerung einer Luftdruck-Ventileinheit für das Bremsmittel der genannten mindestens einen Radachse derart, dass die Bremswirkung auf einen vorgegebenen Wert begrenzt ist, der dem genannten bestimmten Luftdruckwert entspricht.

According to one aspect of the invention, there is provided a method of improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device providing at least two braking means for the wheels Wheel axles of the said vehicle and the method comprises the following steps:

• - Continuously determining an air pressure of said pneumatic parking brake circuit device;
• - Activation of braking by said braking means of said pneumatic parking brake circuit device;
• - Determining an air pressure value in which the braking means of at least one wheel axle of said at least two wheel axles is limited in its braking effect;
• - Controlling an air pressure valve unit for the braking means of said at least one wheel axle such that the braking effect is limited to a predetermined value corresponding to said specific air pressure value.

This advantageously achieves easier parking brake control for a driver of the vehicle, particularly in emergency situations or other situations where vehicle speed must be reduced within a relatively short time.

As a result, the vehicle advantageously maintains its stability when said parking brake circuit is activated during the drive of the vehicle, so that the traffic safety increases and the risk of collisions is reduced.

As a result, a better use of the parking brake means is achieved, which are present on the various axles of the vehicle. In addition, a brake force combination of conventional brakes with brakes of the parking brake circuit is thereby facilitated.

In one aspect of the invention, the braking forces of the braking means are limited at one or more non-priority wheel axles to achieve controlled braking of said vehicle. According to one embodiment, only the braking means is controlled at the rearmost position of the vehicle so that its braking force is limited during braking of the vehicle.

The said braking can take place in an emergency braking situation.

• – Steuerung der genannten Bremswirkung des genannten Bremsmittels durch Steuerung eines Luftdrucks einer Bremskammer des genannten Bremsmittels derart, dass sich die genannte Bremswirkung erhöht, indem der genannte Luftdruck der genannten Bremskammer abgesenkt wird und umgekehrt. Dadurch wird eine genaue und robuste Steuerung der genannten Bremswirkung erzielt. Dadurch kann das genannte Fahrzeug in vorteilhafter Weise zuverlässig und sicher gebremst werden.

The method may include the following step:

• - Controlling said braking action of said braking means by controlling an air pressure of a brake chamber of said braking means such that said braking effect increases by said air pressure of said brake chamber is lowered and vice versa. As a result, an accurate and robust control of the aforementioned braking effect is achieved. Thereby, said vehicle can be braked reliably and safely in an advantageous manner.

• – Steuerung der genannten Bremswirkung des genannten Bremsmittels durch Steuerung eines Luftdrucks einer Bremskammer des genannten Bremsmittels derart, dass die genannte Bremswirkung sich erhöht, indem der genannte Luftdruck der genannten Bremskammer abgesenkt wird, und dass die genannte Bremswirkung sich verringert, indem der genannte Luftdruck der genannten Bremskammer erhöht wird.

The method may include the following step:

• Controlling said braking effect of said brake means by controlling an air pressure of a brake chamber of said brake means such that said braking effect is increased by lowering said air pressure of said brake chamber and said braking effect is reduced by said air pressure of said brake means Brake chamber is increased.

• – Bestimmung des genannten Luftdruckwerts als vorgegebener Luftdruckwert. Dadurch wird eine einfache, effiziente und vorhersehbare Bestimmung des genannten Luftdruckwerts erzielt, die mit minimalem Rechenaufwand der Steuereinheiten des Fahrzeugs verbunden ist.

The method may include the following step:

• - Determination of said air pressure value as a predetermined air pressure value. Thereby, a simple, efficient and predictable determination of said air pressure value is achieved, which is associated with minimal computational effort of the control units of the vehicle.

• – Bestimmung des genannten Luftdruckwerts auf der Basis von Informationen bezüglich mindestens eines der folgenden Kriterien: Fahrzeugkonfiguration, Fahrzeugmasse, Fahrzeuggeschwindigkeit, Querbeschleunigung und Gierrate des genannten Fahrzeugs sowie Lenkwinkel des genannten Fahrzeugs. Dadurch kann der genannte Luftdruckwert mit hoher Genauigkeit bestimmt werden. Anhand beispielsweise der aktuellen Querbeschleunigung und der aktuellen Gierrate des genannten Fahrzeugs kann der genannte Druckwert ermittelt werden, um die Instabilität des genannten Fahrzeugs beim Bremsen mit dem genannten Feststell-Bremskreis zu minimieren.

The method may include the following step:

• Determining said air pressure value based on information regarding at least one of the following criteria: vehicle configuration, vehicle mass, vehicle speed, lateral acceleration and yaw rate of said vehicle, and steering angle of said vehicle. Thereby, said air pressure value can be determined with high accuracy. Based on, for example, the current lateral acceleration and the current yaw rate of said vehicle, said pressure value may be determined to minimize the instability of said vehicle when braking with said parking brake circuit.

• – kontinuierliche Feststellung einer Entwicklung des genannten Luftdruckwerts;
• – kontinuierliche Berücksichtigung des Neigungsgrads der genannten Entwicklung des genannten Luftdruckwerts;
• – Steuerung einer Luftdruck-Ventileinheit für das Bremsmittel der genannten mindestens einen Radachse auf der Basis des genannten Neigungsgrads des genannten Luftdruckwerts zur Begrenzung der genannten Bremswirkung auf den genannten vorgegebenen Wert zum im Wesentlichen gleichen Zeitpunkt, zu dem der genannte Luftdruckwert den genannten bestimmten Luftdruckwert erreicht. Dadurch kann der genannte Luftdruckwert mit hoher Genauigkeit bestimmt werden. Falls der genannte Neigungsgrad der genannten Entwicklung des genannten Luftdruckwerts relativ steil ist, wird der genannte Luftdruckwert als relativ hoher Wert bestimmt, so dass bei der genannten Begrenzung der Bremskraft eine relativ geringe Bremskraft ausgeübt wird.

The method may include the following steps:

• - continuously determining a development of said atmospheric pressure value;
• - continuous consideration of the degree of inclination of said development of said air pressure value;
• - Controlling an air pressure valve unit for the braking means of said at least one wheel axle on the basis of said degree of inclination of said air pressure value for limiting said braking effect to said predetermined value at substantially the same time, when said air pressure value reaches said determined air pressure value. Thereby, said air pressure value can be determined with high accuracy. If said degree of inclination of said development of said air pressure value is relatively steep, said air pressure value is determined to be a relatively high value, so that a relatively low braking force is exerted in the said limitation of the braking force.

• – einem Mittel zur kontinuierlichen Bestimmung eines Luftdrucks der genannten Feststell-Bremskreis-Vorrichtung;
• – einem Mittel zur Aktivierung der Bremsung mit dem genannten Bremsmittel der genannten pneumatischen Feststell-Bremskreis-Vorrichtung;
• – einem Mittel zur Bestimmung eines Luftdruckwerts, bei dem das Bremsmittel mindestens einer Radachse der genannten mindestens zwei Radachsen in Bezug auf die Bremswirkung begrenzt ist;
• – einem Mittel zur Steuerung einer Luftdruck-Ventileinheit für das Bremsmittel der genannten mindestens einen Radachse derart, dass die Bremswirkung auf einen vorgegebenen Wert begrenzt ist, der dem genannten bestimmten Luftdruckwert entspricht.

According to one aspect of the invention, there is provided a system for improving vehicle stability by controlling a pneumatic parking brake circuit device when using said parking brake circuit device for braking, said parking brake circuit device providing at least two braking means for the wheels Wheel axles of the said vehicle comprises, with:

• A means for continuously determining an air pressure of said parking brake circuit device;
• A means for activating braking with said braking means of said pneumatic parking brake circuit device;
• A means for determining an air pressure value at which the braking means of at least one wheel axle of said at least two wheel axles is limited in relation to the braking effect;
• - A means for controlling an air pressure valve unit for the braking means of said at least one wheel axle such that the braking effect is limited to a predetermined value which corresponds to said determined air pressure value.

The system according to the invention may comprise either an electrically controlled parking brake circuit or a pneumatically controlled parking brake circuit.

Said air pressure valve unit is according to one embodiment, an electrically / electronically controlled valve unit. As a result, an accurate and rapid activation of said limitation of the braking force is achieved. When said valve unit is activated, the air pressure of said brake chambers is substantially maintained, resulting in a limitation of said brake means on said at least one wheel axle. According to one embodiment, an air pressure valve unit is provided for each of a plurality of parallel parking brake circuits of the vehicle and controlled according to the invention.

• – ein Mittel zur Steuerung der genannten Bremswirkung des genannten Bremsmittels durch Steuerung eines Luftdrucks einer Bremskammer des genannten Bremsmittels derart, dass die genannte Bremswirkung sich erhöht, indem der genannte Luftdruck der genannten Bremskammer abgesenkt wird und umgekehrt.

The system may include:

• A means for controlling said braking effect of said brake means by controlling an air pressure of a brake chamber of said brake means such that said braking effect increases by lowering said air pressure of said brake chamber and vice versa.

• – ein Mittel zur Steuerung der genannten Bremswirkung des genannten Bremsmittels durch Steuerung eines Luftdrucks einer Bremskammer des genannten Bremsmittels derart, dass sich die genannte Bremswirkung erhöht, indem der genannte Luftdruck der genannten Bremskammer abgesenkt wird, und dass sich die genannte Bremswirkung verringert, indem der genannte Luftdruck der genannten Bremskammer erhöht wird.

The system may include:

• A means for controlling said braking action of said brake means by controlling an air pressure of a brake chamber of said brake means so as to increase said braking effect by lowering said air pressure of said brake chamber, and reducing said braking effect by the aforesaid Air pressure of said brake chamber is increased.

• – ein Mittel zur Bestimmung des genannten Luftdruckwerts als vorgegebener Luftdruckwert.

The system may include:

• - A means for determining said air pressure value as a predetermined air pressure value.

• – ein Mittel zur Bestimmung des genannten Luftdruckwerts auf der Basis von Informationen bezüglich mindestens eines der folgenden Kriterien: Fahrzeugkonfiguration, Fahrzeugmasse, Fahrzeuggeschwindigkeit, Querbeschleunigung und Gierrate des genannten Fahrzeugs sowie Lenkwinkel des genannten Fahrzeugs.

The system may include:

• A means for determining said air pressure value based on information regarding at least one of the following criteria: vehicle configuration, vehicle mass, vehicle speed, lateral acceleration and yaw rate of said vehicle, and steering angle of said vehicle.

• – ein Mittel zur kontinuierlichen Bestimmung einer Entwicklung des genannten Luftdruckwerts;
• – ein Mittel zur kontinuierlichen Berücksichtigung des Neigungsgrads der genannten Entwicklung des genannten Luftdruckwerts;
• – ein Mittel zur Steuerung einer Luftdruck-Ventileinheit für das Bremsmittel der genannten mindestens einen Radachse auf der Basis des genannten Neigungsgrads des genannten Luftdruckwerts zur Begrenzung der genannten Bremswirkung auf den genannten vorgegebenen Wert im Wesentlichen zum gleichen Zeitpunkt, zu dem der genannte Luftdruckwert den genannten bestimmten Luftdruckwert erreicht.

The system may include:

• A means for continuously determining a development of said air pressure value;
• A means for continuously taking into account the degree of inclination of said development of said air pressure value;
• A means for controlling an air pressure valve unit for the braking means of said at least one wheel axle on the basis of said degree of inclination of said air pressure value for limiting said braking effect to said predetermined value substantially at the same time as said air pressure value determines said one Air pressure reached.

In the system, said air pressure valve unit can be adjusted so that substantially no braking effect is available when said pressure valve unit is open, and that said braking effect is limited to a constant value when said pressure valve unit is closed.

Said air pressure valve unit can be actuated electrically and / or pneumatically. This achieves a versatile system according to one aspect of the invention.

According to one aspect of the invention, a vehicle comprising a system according to the present invention is achieved. The named vehicle may be a motor vehicle. The said vehicle may be a truck or a bus.

According to one aspect of the invention, there is provided a computer program for improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device providing at least two braking means for the wheels Wheel axles of the said vehicle comprises. Said computer program comprises program code which causes an electronic control unit or a computer connected to the electronic control unit to perform the steps according to claims 1-5 when said computer program is executed by said electronic control unit or said computer.

According to one aspect of the invention, there is provided a computer program for improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device including braking means for the wheels of at least two wheel axles of said vehicle. Said computer program comprises program code stored in a computer-readable medium and causing an electronic control unit or a computer connected to the electronic control unit to perform the steps according to claims 1-5.

According to one aspect of the invention, there is provided a computer program for improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device including braking means for the wheels of at least two wheel axles of said vehicle. Said computer program comprises program code which is stored in a computer-readable medium and causes an electronic control unit or a computer connected to the electronic control unit to carry out the steps according to claims 1-5 when said computer program is executed by the computer said electronic control unit or said computer is executed.

According to one aspect of the invention, there is provided a computer program product including program code stored in a computer readable medium for carrying out the method steps of claims 1-5 when said computer program is received from an electronic control unit or from a computer, which is connected to the electronic control unit is executed.

According to one aspect of the invention, there is provided a computer program product containing program code stored in a non-transitory computer-readable medium for performing the method steps of claims 1-5 when said computer program is from an electronic control unit or computer which is connected to the electronic control unit is executed.

Other objects, advantages and novel features of the present invention will become apparent to those skilled in the art from the following detailed description and from the practice of the invention. The invention described below is not limited to the specific details described. An expert in the field of the invention who has access to the information in this specification will be expected to recognize other uses, modifications, and inclusions in other fields within the scope of the invention.

Drawing Summary

For a better understanding of the present invention and its further objects and advantages, the following detailed description should be read with the aid of the attached drawings, in which like designations in the various figures refer to the same objects.

is a schematic representation of a vehicle according to an embodiment of the invention.

is a schematic representation of a subsystem for the in shown vehicle according to an embodiment of the invention.

is a schematic representation of a diagram according to an embodiment of the invention.

is a schematic representation of a diagram according to an embodiment of the invention.

Figure 3 is a schematic flow diagram of a method according to an embodiment of the invention.

FIG. 10 is a more detailed flowchart of a method according to one embodiment of the invention. FIG.

is a schematic representation of a computer according to an embodiment of the invention.

Detailed description of the drawing

shows a side view of a vehicle 100 , The vehicle used as an example 100 includes a tractor 110 and a trailer 112 , The vehicle may be a heavy vehicle, such as a truck or bus.

Although the vehicle used as an example is a truck, it is to be understood that the present invention is applicable to various suitable vehicles, such as forest machines, mining vehicles, heavy duty vehicles, construction vehicles, emergency vehicles, etc. The vehicle may be of any suitable configuration have, for example, in the form of one or more units, including at least one trailer.

The tractor 100 According to one embodiment, it is equipped with two wheel axles, with a first, front wheel axle WA1 and with a second, rear axle WA2. However, the present invention is applicable to any vehicle having at least two wheel axles, for example, three or four wheel axles. Thereby, a suitable limitation of braking means of a suitable wheel axle can be activated with the method according to the invention. The limitation of the braking force by braking means of two or more axles can be done in different ways according to an embodiment of the invention.

The term "connection" in the present specification refers to a communication connection that is a physical connection, such as an optoelectronic communication line, or a non-physical connection, such as a wireless connection in the form of a wireless or cellular connection Microwave connection, can act. The connections mentioned here are shown as connections for bidirectional communication. However, in some cases, communication between entities may be via such a link in one direction only.

is a schematic representation of a subsystem 289 of the vehicle 100 , The subsystem 289 includes a pneumatic parking brake circuit device. The subsystem is located in the tractor 110 ,

The subsystem 289 includes a so-called EPB unit (electropneumatic brake system unit) 220 , The named EPB unit 220 serves to provide a pneumatic pressure P in a first front circle 221 , The named EPB unit 220 provides compressed air for a first front brake means BM1a and a second front brake means BM1b, which serve to brake a first front wheel W1a and a second front wheel W1b, respectively. The named first, front circle 221 may comprise at least one channel which serves to supply said compressed air to said first front brake means BM1a and said second front brake means BM1b. Said first front brake means BM1a and said second front brake means BM1b each comprise a brake chamber according to an embodiment. The named EPB unit 220 Thus, a braking force F at said first front wheel W1a and at said second front wheel W1b can be controlled by controlling said air pressure P of said first front circle 221 Taxes. Said first front wheel W1a and said second front wheel W1b are placed on a first front axle WA1.

The named EPB unit 220 may also have a pneumatic pressure P in a second, rear brake circuit 222 provide. According to this embodiment, said pneumatic pressure P in the first, front circle 221 and in the second, rear circle 222 be substantially the same when said pneumatic parking brake circuit device is in a non-braking state. The named EPB unit 220 may supply compressed air to a first rear brake means BM2a and a second rear brake means BM2b which brake a first rear wheel W2a and a second rear wheel W2b, respectively. The aforementioned second, rear circle 222 may comprise at least one channel which serves to supply said compressed air to said first rear braking means BM2a and said second rear braking means BM2b. Said first rear brake means BM1a and said second rear brake means BM2b each comprise a brake chamber according to an embodiment. The named EPB unit 220 can thereby a braking force F at said first rear wheel W2a and said second rear wheel W2b by controlling said air pressure P in said second, rear circle 222 Taxes. Said first rear wheel W2a and said second rear wheel W2b are placed on a rear wheel axle WA2.

A first control unit 200 serves to control the braking effect of said braking means BM1a, BM1b, BM2a, BM2b by controlling an air pressure P of a brake chamber of said brake means such that said braking effect is increased by lowering said air pressure of said brake chamber and vice versa. Each of said brake chambers is equipped, according to one embodiment, with a biased spring device which serves to increase the applied braking force of a wheel associated with it when said pressure P in said brake chamber drops. Consequently, said biased spring device serves to reduce the applied braking force of a wheel associated therewith as said pressure P in said brake chamber increases.

The said first control unit 200 can connect via a L250 with a pressure sensor 250 communicate. The named pressure sensor 250 serves to a prevailing air pressure P in said second, rear circle 222 continuously / intermittently detect / measure / determine. The named pressure sensor 250 can via the said compound L250 continuously or intermittently signals s250 with information about said prevailing air pressure P in said second, rear circle 222 to said first control unit 200 to transfer. The named pressure sensor 250 is between said EPB unit 220 and an air pressure valve unit 260 placed.

The said first control unit 200 can be connected via a link L260 with the mentioned air pressure valve unit 260 communicate. The named air pressure valve unit 260 is an electronically controlled valve unit according to this example.

The named air pressure valve unit 260 is designed so that essentially no braking action is available when said air pressure valve unit 260 is open. The named air pressure valve unit 260 is designed so that said braking effect is limited to a constant value when said air pressure valve unit 260 closed is. As a result, an applied braking force F of said second, rear circle 222 , that is to say the braking means BM2a and BM2b, are limited to a desired value during braking of the vehicle in order to avoid instability. According to this example, the braking means of said first front circle 221 when braking the vehicle 100 not limited, and thereby can exert a maximum available braking force, while a braking force of the braking means of one or more rear wheel axles (according to this example said second, rear wheel axle WA2) is limited to a desired value.

According to one example, a parking brake control means 280 that is connected via L280 to the first control unit 200 can communicate. This allows a user of the vehicle 100 said parking brake control means 280 manually operate, for example, in an emergency braking maneuver of the vehicle. This is particularly advantageous in cases where other conventional brake circuits are totally or partially impaired in their function or in which an additional Bremskraftausübung for the vehicle is required.

It should be noted that, although it is stated in the present specification that said parking brake control means 280 may include a parking brake lever, alternative solutions are also applicable. The said parking brake control means 280 As such, it may include any suitable means for manual or automatic parking brake control.

The said first control unit 200 may determine an air pressure value Px at which a braking means of at least one wheel axle (in this example the second, rear wheel axle WA2) of said at least two wheel axles is limited in relation to the braking action.

The said first control unit 200 can the mentioned air pressure valve unit 260 for the braking means of said at least one wheel axle (according to this example, the second, rear wheel axle WA2) to control so that the braking effect is limited to a predetermined value corresponding to said specific air pressure value Px. This will be explained below with reference to the and explained in more detail.

The said first control unit 200 may determine said air pressure value Px based on information regarding at least one of: vehicle configuration, vehicle mass, vehicle speed, lateral acceleration, yaw rate of said vehicle, and steering angle of said vehicle. Said vehicle configuration may relate to a plurality of wheel axles equipped with parking brake means. Said vehicle configuration may refer to a state of a transmission of the vehicle, e.g. B. which gear is engaged, and / or relate to the current state of a coupling device in the power transmission system of said vehicle. The said first control unit 200 may determine said air pressure value Px on the basis of information about the individual rotational speeds of the wheels W1a, W1b, W2a, W2b. The said first control unit 200 can determine said air pressure value Px on the basis of information about the prevailing air pressure of said braking means BM1a, BM1b, BM2a, BM2b. This allows the first control unit 200 determine a clear air pressure value Px for the said limitation of the braking effect for the braking means of each of said axles. According to one example, the farther the wheel axle is with respect to the drive direction of the vehicle, the more limited is the braking force exerted for a plurality of wheel axles 100 located. The first control unit 200 can thereby determine at least one of the parameters current vehicle mass, current vehicle speed, lateral acceleration, yaw rate of said vehicle and steering angle of said vehicle by any suitable means.

In this case, the first control unit 200 continuously a development of said air pressure value P in said second, rear circle 222 determine and continuously take into account the degree of inclination of said development of said air pressure value P. The first control unit 200 may be an air pressure valve unit according to one example 260 for the braking means of said at least one wheel axle (in this example, said second wheel axle WA2) being controlled on the basis of said degree of inclination of said air pressure value P so as to limit said braking action to said predetermined value, while at substantially the same time said air pressure value reached the said specific air pressure value Px.

According to one embodiment, a pilot control of said air pressure valve unit 260 performed. In this case, a suitable timing allows the air pressure valve unit 260 is completely closed when the specific pressure value Px is reached.

A second control unit 210 can connect via L210 with the first control unit 200 communicate. The second control unit 210 can be detachable with the first control unit 200 be connected. The second control unit 210 can be an external control unit of the vehicle 100 be. The second control unit 210 can perform the innovative process steps according to the invention. The second control unit 210 Can be used to software in the first control unit 200 in particular software for use of the method according to the invention. The second control unit 210 may alternatively via an internal network of the vehicle with the first control unit 200 communicate. The second control unit 210 can be essentially the same functions as the first control unit 200 perform, such as determining said air pressure value Px, wherein the braking means is limited at least one wheel axle of said at least two wheel axles with respect to the braking effect, and controlling said air pressure valve unit for the braking means of said at least one wheel axle such that the braking effect is limited to a predetermined value corresponding to said specific air pressure value.

According to one embodiment, at least one check valve is placed in said parking brake circuits so that, in the event of a malfunction in the control of said air pressure valve, it is possible to increase a prevailing air pressure in the engaged parking brake circuit.

shows a diagram according to an embodiment of the invention.

Here is a prevailing air pressure Pf in the first, front circle 221 represented as a function of time t. In addition, a prevailing air pressure Pr in the second, rear circle 222 represented as a function of time t. The pressure P is given in bar and the time t is given in seconds s.

From the figure it can be seen that the pressure Pr in the second, rear circle 222 is lowered starting from an initial value P1 at a first time t1, to which said actuating means 280 is activated, ie when a user uses said means 280 operated to the said parking brake circuits 221 and 222 to activate. According to one aspect of the invention, said air pressure value Px is determined, and at a second time t2, when said pressures Pf and Pr reach said specific air pressure value Px, said air pressure valve unit becomes 260 activated. As a result, the pressure Pr is maintained at a value substantially corresponding to the specified value Px, while the pressure Pf further decreases and thereby a higher braking force is also exerted by the aforementioned braking means BM1a and BM1b.

shows a diagram according to an embodiment of the invention.

This is a prevailing applied parking brake force Ff in the first, front circle 221 represented as a function of time t. In addition, a prevailing applied parking brake force Fr in the second, rear circle 222 represented as a function of time t. The parking brake force F is given in Newton and the time t is given in seconds s.

From this figure it can be seen that the parking brake force Fr in the second, rear circle 222 from an initial value at said first time t1, to which said actuating means 280 is activated, ie when a user uses said means 280 operated to the said parking brake circuits 221 and 222 to activate. Taking into account these conditions, the said air pressure value Px is determined and said air pressure valve unit 260 is activated at said second time t2. At this time t2, the aforementioned parking brake forces Ff and Fr reach a parking brake force corresponding to the specified air pressure value Px. Thereby, the parking brake force Fr is maintained at a value substantially equal to the specified value Px, while the parking brake force Ff continues to increase, so that a higher braking force is applied by the aforementioned brake means BM1a and BM1b.

By the parking brake force of said second, rear brake circuit 222 is actively limited while the braking force of the first, front brake circuit 221 not at all or to a lesser extent than the braking force of said second, rear brake circuit 222 is limited, according to one aspect of the invention, the stability of said vehicle 100 during a braking of the vehicle 100 be maintained.

• – kontinuierliche Bestimmung eines Luftdrucks P der genannten pneumatischen Feststell-Bremskreis-Vorrichtung;
• – Aktivierung der Bremsung durch das genannte Bremsmittel der genannten pneumatischen Feststell-Bremskreis-Vorrichtung;
• – Bestimmung eines Luftdruckwerts Px, bei dem das Bremsmittel mindestens einer Radachse der genannten mindestens zwei Radachsen in Bezug auf die Bremswirkung begrenzt ist;
• – Steuerung einer Luftdruck-Ventileinheit 260 für das Bremsmittel der genannten mindestens einen Radachse derart, dass die Bremswirkung auf einen vorgegebenen Wert Fx begrenzt wird, der dem genannten bestimmten Luftdruckwert Px entspricht.

schematically shows a flowchart of a method for improving the vehicle stability by controlling a pneumatic parking brake circuit device 222 when using said parking brake circuit device 222 for braking, comprising braking means for the wheels of at least two wheel axles of said vehicle. The method comprises a first method step s401. The step s401 comprises the following substeps:

• - Continuous determination of an air pressure P of said pneumatic parking brake circuit device;
• - Activation of braking by said braking means of said pneumatic parking brake circuit device;
• - Determining an air pressure value Px, wherein the braking means is limited at least one wheel axle of said at least two wheel axles with respect to the braking effect;
• - Control of an air pressure valve unit 260 for the braking means of said at least one wheel axle such that the braking effect is limited to a predetermined value Fx which corresponds to said specific air pressure value Px.

After method step s401, the implementation of the method ends.

Figure 11 is a schematic representation of a flowchart of a method of improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device providing braking means for the wheels of at least two wheel axles of said vehicle. This method comprises a method step s410. The step s410 comprises a substep in which an air pressure P of said pneumatic parking brake circuit device is continuously determined. This is done by means of the mentioned air pressure sensor 250 and said first control unit 200 , The method step s410 is followed by a further method step s420.

Step s420 comprises a substep in which the braking is activated by said braking means of said pneumatic parking brake circuit device. This is done by actuating said parking brake control means 280 , This can be done by a user of the vehicle 100 be done manually. According to an alternative embodiment, said first control unit 200 automatically activate the braking by said braking means of said pneumatic parking brake circuit device. The method step s420 is followed by a further method step s430.

Step s430 comprises a sub-step in which an air pressure value Px is determined at which the braking means of at least one wheel axle of said at least two wheel axles is limited in relation to the braking effect. This is done by means of said first control unit 200 , This can be done in many different ways.

According to a first example, said air pressure value Px is determined on the basis of a current vehicle mass. In this case, a relatively low air pressure value Px is determined when said vehicle mass is relatively large. In this case, a relatively high air pressure value Px is determined when said vehicle mass is relatively small.

According to a second example, said air pressure value Px is determined based on the current vehicle speed. In this case, a relatively low air pressure value Px is determined when said vehicle speed is relatively high. In this case, a relatively high air pressure value Px is determined when said vehicle speed is relatively low.

According to a third example, said air pressure value Px is determined on the basis of a current lateral acceleration of the vehicle. In this case, a relatively low air pressure value Px is determined when said lateral acceleration of the vehicle is relatively high. In this case, a relatively high air pressure value Px is determined when said lateral acceleration of the vehicle is relatively low.

According to a fourth example, said air pressure value Px is determined on the basis of the current yaw rate of said vehicle. In this case, a relatively low air pressure value Px is determined if the said yaw rate of said vehicle is relatively low. In this case, a relatively high air pressure value Px is determined when said yaw rate of said vehicle is relatively high.

According to a fifth example, said air pressure value Px is determined on the basis of a current steering angle of said vehicle. In this case, a relatively low air pressure value Px is determined when said steering angle of said vehicle is relatively large. In this case, a relatively high air pressure value Px is determined when said steering angle of said vehicle is relatively small.

According to one embodiment of the innovative method, a criterion for limiting said braking effect according to said determined air pressure value Px is that a current vehicle speed is greater than zero, i. H. that the vehicle is moving / driven.

The method step s430 is followed by a further method step s440.

Step s440 includes a substep in which said air pressure valve unit 260 is controlled for the braking means of said at least one wheel axle so that the braking effect is limited to a predetermined value corresponding to said specific air pressure value Px. This is done by means of said first control unit 200 , said second control unit 210 and / or said EPB unit 220 ,

After method step s440, the execution of the method ends.

is a diagram of an embodiment of a device 500 , The reference to described control units 200 and 210 can in one embodiment the device 500 include. The device 500 includes a non-volatile memory 520 , a data processing unit 510 and a read / write memory 550 , The non-volatile memory 520 has a first memory element 530 , in which a computer program, for example an operating system, is stored, which serves the function of the device 500 to control. The device 500 Also includes a bus controller, a serial communication port, I / O means, an A / D converter, a time and date acquisition and transmission unit, an event counter, and an interrupt controller (not shown). The non-volatile memory 520 also has a second memory element 540 ,

According to one aspect of the invention, there is provided a computer program P comprising vehicle stability improving routines by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device providing brake means for the wheels of at least two axles of said vehicle comprises.

The computer program may include routines that serve to continuously determine an air pressure P of said pneumatic parking brake circuit device. The computer program may include routines that serve to activate braking by said braking means of said pneumatic parking brake circuit device. The computer program may include routines that serve to determine an air pressure value Px at which the braking means at least one wheel axle of said at least two wheel axles with respect to Braking effect is limited. The computer program may include routines for controlling an air pressure valve unit for the braking means of said at least one wheel axle so as to limit the braking effect to a predetermined value corresponding to said determined air pressure value Px.

The computer program may comprise routines which serve to control said braking effect of said brake means by controlling an air pressure of a brake chamber of said brake means to increase said braking effect by reducing said air pressure of said brake chamber and vice versa.

The computer program may include routines which serve to determine the said air pressure value Px as the predetermined air pressure value.

The computer program may include routines for determining said air pressure value Px based on information regarding at least one of: vehicle configuration, vehicle mass, vehicle speed, lateral acceleration of said vehicle, yaw rate of said vehicle, and steering angle of said vehicle.

The computer program may comprise routines which serve to continuously determine a development of said air pressure value P. The computer program may include routines for continuously considering the degree of inclination of said development of said air pressure value P. The computer program may include routines for controlling an air pressure valve unit for the braking means of said at least one wheel axle based on said degree of inclination of said air pressure value P such that said braking effect is limited to said predetermined value while substantially simultaneously said air pressure value reached the said specific air pressure value Px.

The program P can be executed in executable or compressed form in a memory 560 and / or in a read-write memory 550 be saved.

If it is mentioned that the data processing unit 510 performs a particular function, it should be understood that it executes a specific part of the program that is in memory 560 is stored or executes a specific part of the program in the read / write memory 550 is stored.

The data processing unit 510 can via a data bus 515 with a data port 599 communicate. The non-volatile memory 520 is used for communication with the data processing unit 510 via a data bus 512 , The separate memory 560 can via a data bus 511 communicate with the data processing unit. The read / write memory 550 can via a data bus 514 with the data processing unit 510 communicate. For example, connections L210, L220, L250, and L260 may be to the data port 599 be connected (see ).

When data is at the data port 599 run in, these are temporarily in the second memory element 540 saved. If the accumulated data has been temporarily stored, is the data processing unit 510 ready to execute code as described above. According to one embodiment, these include the data port 599 incoming signals information about a current pressure P in each parking brake circuit of the vehicle 100 , According to one embodiment, these include the data port 599 incoming signals Information about the vehicle configuration, the vehicle mass, the vehicle speed, the lateral acceleration of the vehicle, the yaw rate of said vehicle and the steering angle of said vehicle, etc. The data port 299 Incoming signals may be from the device 500 be used to determine said air pressure value Px, wherein the braking means is limited at least one wheel axle of said at least two wheel axles with respect to the braking effect, and the air pressure valve unit 260 to control for the braking means of said at least one wheel axle so that the braking effect is limited to a predetermined value corresponding to said specific air pressure value Px.

Portions of the procedures described herein may be used by the facility 500 by means of the data processing unit 510 running the program that runs in memory 560 or in the read / write memory 550 is stored. If the device 500 running the program, procedures described in this document are performed.

The above description of the preferred embodiments of the present invention is provided by way of illustration. This description is not intended to be exhaustive and is not intended to limit the invention to the variants described. As expected, many variations and modifications are readily apparent to one skilled in the art. The embodiments have been chosen and described in order to explain the principles of the inventions and their practical applications in the best possible way and it thereby enabling an expert in the field of the invention to understand the invention for different embodiments and with the various modifications suitable for the intended use.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2615003 [0007]

Claims (16)

Method for improving vehicle stability by controlling a pneumatic parking brake circuit device ( 289 ; 221 ; 222 ) when using said parking brake circuit device ( 289 ; 221 ; 222 ) for braking, wherein said parking brake circuit device ( 289 ; 221 ; 222 ) a braking means (BM1a, BM1b, BM2a, BM2b) for the wheels (W1a, W1b, W2a, W2b) of at least two wheel axles (WA1, WA2) of said vehicle ( 100 ) comprising the following steps: - continuous determination (s410) of an air pressure (P) of said pneumatic parking brake circuit device ( 289 ; 221 ; 222 ); Activation (s420) of braking with said brake means (BM1a, BM1b, BM2a, BM2b) of said pneumatic parking brake circuit device ( 289 ; 221 ; 222 ); characterized by the following steps: - determining (s430) an air pressure value (Px) at which the braking means (BM2a, BM2b) of at least one wheel axle (WA2) of said at least two wheel axles is limited in relation to the braking effect; Control (s440) of an air pressure valve unit ( 260 ) for the braking means (BM2a, BM2b) of said at least one wheel axle (WA2) such that the braking effect is limited to a predetermined value (Fx) corresponding to said determined air pressure value (Px). Method according to claim 1 with the following step: Controlling said braking effect of said brake means (BM2a, BM2b) by controlling an air pressure of a brake chamber of said brake means (BM2a, BM2b) such that said braking effect increases by lowering said air pressure of said brake chamber and vice versa. Method according to claim 1 or 2, comprising the following step: - Determination of said air pressure value (Px) as a predetermined air pressure value. Method according to claim 1 or 2, comprising the following step: Determining said air pressure value (Px) based on information regarding at least one of the following criteria: vehicle configuration, vehicle mass, vehicle speed, lateral acceleration of the vehicle, yaw rate of said vehicle, and steering angle of said vehicle. Method according to one of the claims 1-4, comprising the following steps: - continuously determining a development of said air pressure value (P); - continuous consideration of the degree of inclination of said development of said air pressure value (P); Control of said air pressure valve unit ( 260 for the brake means (BM2a, BM2b) of said at least one wheel axle on the basis of said degree of inclination of said air pressure value (P) for limiting said braking effect to said predetermined value (Fx), while substantially simultaneously (t2) said air pressure value (P) reaches said specific air pressure value (Px). System for improving vehicle stability by controlling a pneumatic parking brake circuit device ( 289 ; 221 ; 222 ) when using said parking brake circuit device ( 289 ; 221 ; 222 ) for braking, wherein said parking brake circuit device ( 289 ; 221 ; 222 ) Braking means (BM1a; BM1b; BM2a; BM2b) for the wheels (W1a; W1b; W2a; W2b) of at least two wheel axles (WA1; WA2) of said vehicle, comprising 200 ; 210 ; 500 ; 250 ) for continuously determining an air pressure (P) of said pneumatic parking brake circuit device ( 289 ; 221 ; 222 ); - a means ( 200 ; 210 ; 500 ; 280 ) for activating braking with said brake means (BM1a, BM1b, BM2a, BM2b) of said pneumatic parking brake circuit device ( 289 ; 221 ; 222 ), characterized by: - a means ( 200 ; 210 ; 500 ) for determining an air pressure value (Px) at which the braking means (BM2a, BM2b) of at least one wheel axle (WA2) of said at least two wheel axles (WA1; WA2) is limited in relation to the braking effect; - a means ( 200 ; 210 ; 500 ) for controlling an air pressure valve unit ( 260 ) for the braking means (BM2a, BM2b) of said at least one wheel axle (WA2) such that the braking effect is limited to a predetermined value (Fx) corresponding to said determined air pressure value (Px). System according to claim 6, comprising: - a means ( 200 ; 210 ; 500 ) for controlling said braking effect of said brake means by controlling an air pressure of a brake chamber of said brake means, so that said braking effect is increased by lowering said air pressure of said brake chamber and vice versa. System according to claim 6 or 7, comprising: - a means ( 200 ; 210 ; 500 ) for determining said air pressure value (Px) as a predetermined air pressure value. System according to claim 6 or 7, comprising: - a means ( 200 ; 210 ; 500 ) for determining said air pressure value (Px) based on information regarding at least one of the following criteria: vehicle configuration, vehicle mass, vehicle speed, lateral acceleration and yaw rate of said vehicle, and steering angle of said vehicle. A system according to any one of claims 6-9, comprising: - means ( 200 ; 210 ; 500 ; 250 ) for continuously determining a development of said air pressure value (P); - a means ( 200 ; 210 ; 500 ) for continuously taking into account the degree of inclination of said development of said air pressure value (P); - a means ( 200 ; 210 ; 500 ) for controlling said air pressure valve unit ( 260 ) for the braking means of said at least one wheel axle on the basis of said degree of inclination of said air pressure value (P) such that said braking effect is limited to said predetermined value, while substantially simultaneously said air pressure value reaches said determined air pressure value (Px) , System according to one of the claims 6-10, wherein said air pressure valve unit ( 260 ) is designed so that substantially no braking effect is available when said air pressure valve unit ( 260 ), and that said braking effect is limited to a constant value when said compressed air valve unit is closed. A system according to any one of claims 6-11, wherein said air pressure valve unit ( 260 ) can be operated electrically and / or pneumatically. Vehicle ( 100 ; 110 ) with a system according to one of the claims 6-12. Vehicle ( 100 ; 110 ) according to claim 13, which may be a truck or a bus. A computer program (P) for improving vehicle stability by controlling a pneumatic parking brake circuit device using said parking brake circuit device for braking, said parking brake circuit device comprising braking means for the wheels of at least two wheel axles of said vehicle and said computer program (P) comprises program code which causes an electronic control unit ( 200 ; 500 ) or another computer ( 210 ; 500 ) connected to the electronic control unit ( 200 ; 500 ) is performed, the steps according to one of the claims 1-5 performs. Computer program product with program code stored in a computer-readable medium for carrying out the method steps according to one of the claims 1-5, when said computer program is stored by an electronic control unit ( 200 ; 500 ) or from a computer ( 210 ; 500 ) connected to the electronic control unit ( 200 ; 500 ) is connected.

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