WO2006118541A1

WO2006118541A1 - A method and a device for stabilizing of trucks

Info

Publication number: WO2006118541A1
Application number: PCT/SE2006/050093
Authority: WO
Inventors: Anders Gustavsson
Original assignee: Scania Cv Ab (Publ)
Priority date: 2005-05-04
Filing date: 2006-05-03
Publication date: 2006-11-09
Also published as: SE527224C2; DE112006001116T5; SE0501018L

Abstract

Method for stabilisation of a tractor unit for freight vehicles, comprising imposed limitation of the tractor unit's speed. The method is distinguished in particular by the fact that the limitation is applied when the tractor unit is travelling with no trailer and the fact that the tractor unit's maximum permissible speed (v) is controlled on the basis of the degree of fullness (0) of the tractor unit's fuel tank. The invention also relates to a device for stabilisation of a tractor unit.

Description

A Method and device for stabilizing of trucks

1. Background

1.1 Technical field

The present invention relates to a method according to the introductory portion of the attached claim 1.

The invention also relates to a device according to the introductory portion of the attached claim 8.

1.2 Description of the state of the art

Systems for preventing, for example, freight vehicles from becoming unstable and overturning are previously known and comprise complicated devices for measuring, for example, the angle of inclination of the vehicle and for limiting the vehicle's speed by braking on the basis of the results of such measurements. Systems of this kind are complicated and expensive and involve inter alia special sensors etc. and brake- operating means and control based on symptoms, which may prove to be unreliable. Tractor units for freight vehicles in the absence of a trailer are particularly liable to instability.

The object in this respect of the present invention is to prevent instability of tractor units by simple, inexpensive and reliable means, preferably using information and technology which already exist in tractor units.

2. Summary of the invention

The above object is achieved by a method and a device according to the attached claims 1 and 8 respectively.

RFCORD COPY - TRANSLATION J Further advantages are afforded by what is indicated in the respective dependent claims.

3. Brief description of the drawings

The invention is described in more detail below in relation to examples of embodiments and the attached drawings, in which

- Fig. 1 depicts schematically in block diagram form an embodiment of a device according to the invention for a tractor unit and

- Fig. 2 depicts schematically a pattern of relationship between vehicle speed and fuel tank fullness according to the invention.

4. Detailed description of preferred embodiments

In Fig. 1, ref. 1 denotes control devices arranged for stabilisation, tilt stabilisation, by imposed limitation of the speed of a tractor unit 2, whereby said devices are arranged and intended to be activated when the tractor unit is adapted to being driven with no trailer and is thereby particularly liable to tilting because of deficient stability as a result of its height in combination with relatively low weight and short distance between front wheels and rear wheels.

The control devices 1 are in this case adapted to controlling the tractor unit's maximum permissible speed on the basis of the degree of fullness 0 of the tractor unit's fuel tank, see Fig. 2. According to preferred embodiments, the control devices are adapted to allowing a maximum speed v_max at degrees of tank fullness ranging from full tank down to an upper fullness limit 0_\. The control devices are also adapted to allowing a speed of nil or close to nil at a degree of fullness below a lower fullness limit 0₂. In addition, the control devices according to preferred embodiments are adapted to following a predetermined prescribed relationship between fuel tank fullness and maximum permissible speed at degrees of fullness between the upper fullness limit and the lower fullness limit, which relationship need not be rectilinear, as in Fig. 2, since other relationships are conceivable depending on the tractor unit's stability characteristics.

It is also preferred that the control devices be arranged and intended to be supplied with existing internal signals of the tractor unit for vehicle speed and tank fullness and devices 5, e.g. for power output limitation in order to apply imposed limitation of the tractor unit's speed. Examples of such signals are supply signals to the fuel gauge 3 and speedometer 4, with tank fullness and vehicle speed measured in conventional known ways.

It is also preferred that the control applied by the control devices be intended to be adapted to the tractor unit's configuration and stability characteristics, which comprises adjustment of the relationship between maximum permissible speed and tank fullness as previously mentioned, an example of which appears in Fig. 2.

According to a version which in certain situations is preferred, the upper fullness limit 0_\ is about 75% of full tank and the lower fullness limit 0₂ is about 25% of full tank.

The method and the function of the device according to the invention are probably substantially indicated above.

The stability conditions for a tractor unit are altered substantially by the degree of fullness of the fuel tank, whereby the tank fullness according to the invention is used for controlling the maximum permissible speed, possibly using existing internal signals and control and monitoring functions of the tractor unit.

The invention is described above in relation to embodiment examples and preferred embodiments.

Further embodiments and also minor modifications and additions are of course conceivable without thereby departing from the basic concept of the invention. Thus other fullness limits than 75 and 25% are of course conceivable.

The invention is therefore not to be regarded as limited to the embodiments indicated above but may be varied within its scope indicated by the attached claims.

Claims

1. A method for stabilisation of a tractor unit for freight vehicles comprising imposed limitation of the tractor unit's speed, characterised in that

- the limitation is applied when the tractor unit (2) is travelling with no trailer, and in that

- the tractor unit's maximum permissible speed (v) is controlled on the basis of the degree of fullness (0) of the tractor unit's fuel tank.

2. A method according to claim 1, characterised in that the control applied allows full vehicle speed (v_max) at degrees of tank fullness ranging from full tank down to an upper fullness limit (øj).

3. A method according to claim 1 or 2, characterised in that at a degree of fullness below a lower fullness limit (0₂) the control applied allows only a vehicle speed of nil or close to nil.

4. A method according to claim 1, 2 or 3, characterised in that the control applied follows a specified prescribed relationship between tank fullness and maximum permissible speed at degrees of fullness ranging between an upper fullness limit and a lower fullness limit.

5. A method according to claim 1, 2, 3, or 4, characterised in that the control applied is supplied with existing internal signals of the vehicle for speed and tank fullness as a basis for the control applied and for limiting, for example, power output in order to apply imposed limitation of the tractor unit's speed.

6. A method according to any one of the foregoing claims, characterised in that the control applied is adapted to the tractor unit's configuration and stability characteristics.

7. A method according to claim 4, characterised in that the upper fullness limit is about 75% of Ml tank and the lower fullness limit is about 25% of full tank.

8. A device for stabilisation of a tractor unit for freight vehicles comprising devices for imposed limitation of the tractor unit's speed, characterised in that said devices (1) are arranged and intended to be activated when the tractor unit (2) is adapted to travelling with no trailer and in that control devices (1) are provided for controlling the tractor unit's maximum permissible speed (v) on the basis of the degree of fullness (0) of the tractor unit' s fuel tank.

9. A device according to claim 8, characterised in that the control devices are adapted to allowing maximum vehicle speed (v_max) at degrees of fullness ranging from full tank down to an upper fullness limit (O₁).

10. A device according to claim 8 or 9, characterised in that the control devices (1) are adapted to allowing a vehicle speed of nil or close to nil at a degree of tank fullness below a lower fullness limit (0₂).

11. A device according to claim 8, 9 or 10, characterised in that the control devices (1) are adapted to following a predetermined prescribed relationship between tank fullness and maximum permissible speed at degrees of tank fullness ranging between an upper fullness limit (0_\) and a lower fullness limit (0₂).

12. A device according to any one of claims 8-11, characterised in that the control devices are arranged and intended to be supplied with existing internal signals of the vehicle for speed and tank fullness as a basis for control and for limitation of, for example, power output in order to limit the tractor unit's maximum permissible speed

(V).

13. A device according to any one of claims 8-12, characterised in that the control devices are arranged for adjustment of the control applied to the tractor unit's configuration and stability characteristics.

14. A device according to claim 11 , characterised in that the upper fullness limit is