DEVICE AND METHOD FOR DETERMINING THE VERTICAL POSITION OF A VEHICLE'S CENTER OF GRAVITY

Abstract

One aspect of the invention relates to a device 1 for determining the vertical position of the center of gravity C of a vehicle 2, said device 1 comprising: First weighing means 3 configured to support the wheels of a first wheel assembly 4 and determine mass values ​​measured at the level of the first wheel assembly 4; Second weighing means 5 configured to support the wheels of a second wheel assembly 6 and determine mass values ​​measured at the level of the second wheel assembly 6; Said first weighing means 3 comprising: Pulling means 7 configured to pull and lift the first wheel assembly 4 in a vertical direction Y; and Displacement means 8 configured to move the pulling means 7 in a horizontal direction X. Figure 1

Description

Title of the invention: DEVICE AND METHOD FOR DETERMINING THE VERTICAL POSITION OF A VEHICLE'S CENTER OF GRAVITY

[0001] The invention relates to a device and a method for determining the vertical position of the center of gravity of a motor vehicle. The technical field of the invention thus relates to that of determining the center of gravity of a motor vehicle.

[0002] A device for determining the position of the center of gravity of a motor vehicle is known from document CN-A-111855080. The device comprises a first platform on which the wheels of the front axle of the vehicle are placed, and a second platform supporting the wheels of the rear axle. The first platform includes first weighing means capable of determining a first mass measured at the level of the front axle. The second platform includes second weighing means capable of determining a second mass measured at the level of the rear axle.

[0003] It should be noted that the second platform is arranged on a lifting table capable of vertically lifting the rear wheel assembly of the vehicle.

[0004] To perform a measurement of the center of gravity on the vehicle, the rear wheel assembly is raised using the lifting table and a mass transfer is measured using the first and second weighing means when the rear wheel assembly is raised.

[0005] However, when the rear wheel assembly is raised, friction occurs between the rear wheels and the second platform. To counteract the forces generated by this friction, additional friction also develops between the front wheel assembly and the first platform. This friction consequently distorts the measurements, and therefore the determination of the vehicle's center of gravity position.

[0006] The object of the invention is to overcome the disadvantages of the prior art by proposing a device for determining a precise vertical position of a center of gravity of a motor vehicle.

[0007] In this context, the invention thus relates, in its broadest sense, to a device for determining the vertical position of the center of gravity of a motor vehicle, the device comprising: • Initial weighing means configured to support wheels of a first set of wheels of the vehicle and determine mass values ​​measured at the level of the first set of wheels; • Second weighing means configured to support wheels of a second set of wheels of the vehicle and determine mass values ​​measured at the level of the second set of wheels.

[0008] The device according to this aspect of the invention is remarkable in that the first weighing means comprise: • Pulling means configured to pull and lift the first set of wheels in a vertical direction, said vertical direction being parallel to a direction of gravity; and • Means of movement configured to, simultaneously with the lifting of the first set of wheels, move the pulling means in a horizontal direction perpendicular to the vertical direction.

[0009] Thanks to the combination of these pulling means and these means for moving the pulling means, a set of wheels of the vehicle is pulled vertically from the top of the vehicle. Thus, unlike prior art devices, no force is generated by the friction of the wheels on the weighing means. The measurement of the vertical position of the center of gravity is therefore more precise.

[0010] In addition to the characteristics mentioned in the preceding paragraph, the device according to the invention may have one or more additional characteristics from among the following, considered individually or according to all technically possible combinations.

[0011] According to a non-limiting aspect of the invention, the pulling means are configured to lift, in the vertical direction, the first wheel assembly over a distance between 0mm and 1000mm, typically 0mm and 570mm.

[0012] According to a non-limiting aspect of the invention, the first weighing means comprise a support surface for the wheels of the first wheel set, the support surface being formed by a flat surface or two rollers parallel to each other and free to rotate around their longitudinal axis of rotation.

[0013] According to a non-limiting aspect of the invention, the pulling means are formed by an electric hoist.

[0014] Another aspect of the invention relates to a method for determining the vertical position of the center of gravity of a motor vehicle by means of a device according to any one of the aforementioned aspects of the invention, the method comprising the steps of, when the wheels of the first set of wheels are positioned on the first weighing means and the wheels of the second set of wheels are positioned on the second weighing means: • Determine, using the first weighing methods, a first mass value measured at the level of the first set of wheels and, using the second weighing means, a first mass value measured at the level of the second set of wheels; • Pull and lift, using the pulling means, the first set of wheels in the vertical direction; • Simultaneously with the lifting of the first set of wheels, move, via the means of movement, the pulling means in the horizontal direction so that said pulling means pull and lift said first set of wheels in the vertical direction; • Determine, via the first weighing means, a second mass value measured at the level of the first wheel assembly and, via the second weighing means, a second mass value measured at the level of said second wheel assembly; • Determine a vertical position of a center of gravity of the vehicle as a function of the aforementioned determined mass values.

[0015] According to a non-limiting aspect of the invention, prior to the step of determining a vertical position of a center of gravity of the vehicle, the method comprises the steps of: • Release, via the pulling means, the first set of wheels in the vertical direction; • Simultaneously with the release of the first set of wheels, move, via the means of movement, the pulling means in the horizontal direction so that the pulling means release the first set of wheels in the vertical direction; • Repeat at least once all the steps prior to the step of determining a vertical position of a center of gravity of the vehicle.

[0016] According to a non-limiting aspect of the invention, when the support surface is formed by two rollers parallel to each other and free to rotate around their longitudinal axis of rotation, the vehicle's parking brake is activated.

[0017] According to a non-limiting aspect of the invention, when the support surface is formed by two rollers parallel to each other and free to rotate around their longitudinal axis of rotation, a vehicle speed is engaged.

[0018] According to a non-limiting aspect of the invention, when the support surface is formed by a flat surface, the parking brake is deactivated and all vehicle gears are disengaged.

[0019] The invention and its various applications will be better understood by reading the following description and examining the accompanying figures.

[0020] [Fig.1] illustrates, schematically, a device for determining a vertical position of a center of gravity of a motor vehicle according to a non-limiting aspect of the invention.

[0021] [Fig.2] represents, schematically, a non-limiting embodiment of a method for determining a vertical position of a center of gravity of a motor vehicle according to a non-limiting aspect of the invention.

[0022] Fig. 1 illustrates a non-limiting example of an embodiment of a device 1 for determining a vertical position of a center of gravity C of a motor vehicle 2.

[0023] The device 1 includes first weighing means 3 configured to support wheels of a first wheel set 4 and to determine mass values ​​measured at the level of the first wheel set 4. In order to measure these mass values, these first weighing means 3 may include a balance.

[0024] The device 1 also includes second weighing means 5 configured to support wheels of a second wheel set 6 of the vehicle 2 and to determine mass values ​​measured at the level of the second wheel set 6. In order to measure these mass values, these second weighing means 5 may include a balance.

[0025] The first weighing means 3 comprise pulling means 7 configured to pull and lift the first wheel set 4 in a vertical direction Y parallel to the direction of gravity.

[0026] According to one non-limiting embodiment, the pulling means 7 are formed by an electric hoist. According to other non-limiting examples, the pulling means 7 may be formed by a manual hoist or a winch.

[0027] In order for the first wheel set 4 to be pulled upwards in the vertical direction Y, the first weighing means 3 also include displacement means 8 configured to, simultaneously with the lifting of the first wheel set 4, move the pulling means 7 in a horizontal direction X perpendicular to the vertical direction Y.

[0028] These means of movement 8 can be formed by an electric trolley mounted on a horizontal bar 9 of a gantry 10. Thus, by moving along the horizontal bar 9, the electric trolley 8 moves the pulling means 7 in the horizontal direction X as the first wheel assembly 4 rises in the vertical direction Y. Maintaining this verticality, ensured by the horizontal movement of the pulling means 7, eliminates friction between the wheels of the first and second wheel assemblies 4, 6, and the bearing surface of these wheels.

[0029] In the non-limiting illustrated example, the first weighing means 3 comprise a bearing surface 11 for the wheels of the first wheel set 4, said bearing surface 11 being formed by two parallel rollers free to rotate around their longitudinal axis of rotation 12.

[0030] Thus, thanks to these rollers, it is possible to activate the parking brake so as to lock the wheels of vehicle 2.

[0031] It should be noted that when one set of wheels of the vehicle is lifted, the distance between the two sets of wheels changes as the vehicle is raised. If the wheels are prevented from rotating by the parking brake, significant forces are generated at the wheel sets. Such forces risk damaging both the vehicle and the measuring device. Therefore, in prior art devices, the parking brake is never activated. However, with the advent of electric emergency brakes, it is common for the parking brake to activate during the raising of the wheel set. In this case, the measurement must be repeated. The rollers according to the invention, which can pivot, overcome this drawback.

[0032] Fig. 2 illustrates a method 100 for determining the vertical position of a center of gravity C of a vehicle 2 according to a non-limiting aspect of the invention.

[0033] The method 100 includes, when the wheels of the first wheel set 4 are positioned on the first weighing means 3 and the wheels of the second wheel set 6 are positioned on the second weighing means 5, a step of determining 101, via the first weighing means 3, a first mass value measured at the level of the first wheel set 4 and, via the second weighing means 5, a first mass value measured at the level of the second wheel set 6. In other words, mass values ​​are measured when the vehicle 2 is on the ground.

[0034] Then, the method 100 includes a step of pulling and lifting 102, via the pulling means 7, the first set of wheels 4 in the vertical direction Y.

[0035] In order for the pulling means 7 to lift the first wheel set 4 in the vertical direction Y, simultaneously with the pulling and lifting step 102, the method 100 performs a moving step 103, via the moving means 8, the pulling means 7 in the horizontal direction X. Thus, the first wheel set 4 moves in a direction parallel to the direction of gravity and in the opposite direction to the direction of gravity.

[0036] Maintaining this verticality, ensured by the horizontal movement of the pulling means 7, eliminates friction between the wheels and the bearing surface of these wheels.

[0037] When the first wheel assembly 4 is lifted, the method 100 performs a step of determining 104, via the first weighing means 3, a second mass value measured at the level of the first wheel assembly 4 and, via the second weighing means 5, a second mass value measured at the level of the second wheel assembly 6.

[0038] The process 100 then includes a step of releasing 105, via the pulling means 7, the first wheel set 4 in the vertical direction Y. Thus, during this release step, the first wheel set 4 moves vertically in the direction of gravity.

[0039] In order for the pulling means 7 to release the first wheel set 4 in the vertical direction Y, simultaneously with the release step 105, the method 100 includes a step of moving 106, via the moving means 8, the pulling means 7 in the horizontal direction X.

[0040] Maintaining this verticality, ensured by the horizontal movement of the pulling means 7, eliminates friction between the wheels and the bearing surface of these wheels.

[0041] According to a non-limiting implementation, the process 100 includes a step of repeating 107 at least once all the preceding steps 101 to 106.

[0042] Then, the method 100 includes a step of determining 108 a vertical position of the center of gravity C of the vehicle 2 as a function of the determined mass values.

[0043] According to a non-limiting implementation, when the bearing surface 11 of the first weighing means 3 is formed by two rollers parallel to each other and free to rotate around their axis of rotation, the parking brake can be activated and / or a vehicle speed can be engaged.

[0044] Conversely, when the bearing surface 11 of the first weighing means 3 is formed by a flat surface (not shown), the parking brake is deactivated and all vehicle gears are disengaged. In other words, the vehicle wheels can pivot.

Claims

Demands

1. Device (1) for determining a vertical position of a center of gravity (C) of a motor vehicle (2), said device (1) comprising: - First weighing means (3) configured to support wheels of a first wheel set (4) of said vehicle (2) and to determine mass values ​​measured at said first wheel set (4); - Second weighing means (5) configured to support wheels of a second wheel set (6) of said vehicle (2) and to determine mass values ​​measured at said second wheel set (6); - Said device (1) being characterized in that said first weighing means (3) comprise: • Pulling means (7) configured to pull and lift said first wheel set (4) in a vertical direction (Y), said vertical direction (Y) being parallel to a direction of gravity;and • Displacement means (8) configured to, simultaneously with the lifting of said first set of wheels (4), move said pulling means (7) along a horizontal direction (X) perpendicular to said vertical direction (Y).;

2. Device (1) according to the preceding claim, characterized in that the pulling means (7) are configured to lift, in the vertical direction (Y), the first wheel set (4) over a distance between 0mm and 1000mm.

3. Device (1) according to any one of the preceding claims, characterized in that the first weighing means (3) comprise a bearing surface (11) for the wheels of the first wheel set (4), said bearing surface (11) being formed by a flat surface or two rollers parallel to each other and free to rotate about their longitudinal axis of rotation (12).

4. Device (1) according to any one of the preceding claims, characterized in that the pulling means (7) are formed by an electric hoist.

5. A method (100) for determining a vertical position of a center of gravity (C) of a motor vehicle (2) by means of a device (1) according to any one of the preceding claims, said method (100) comprising the steps of, when the wheels of the first wheel set (4) are positioned on the first weighing means (3) and the wheels of the second wheel set (6) are positioned on the second weighing means (5): • Determining (101), via the first weighing means (3), a first mass value measured at said first wheel set (4) and, via the second weighing means (5), a first mass value measured at said second wheel set (6); • Pulling and lifting (102), via the pulling means (7), said first wheel set (4) in the vertical direction (Y);• Simultaneously with the lifting of said first wheel assembly (4), move (103), via the movement means (8), said pulling means (7) in the horizontal direction (X) so that said pulling means (7) pull and lift said first wheel assembly (4) in said vertical direction (Y); • Determine (104), via the first weighing means (3), a second mass value measured at said first wheel assembly (4) and, via the second weighing means (5), a second mass value measured at said second wheel assembly (6); • Determine (108) a vertical position of a center of gravity (C) of said vehicle (2) as a function of said determined mass values.

6. A method (100) according to the preceding claim, characterized in that prior to the step of determining (108) a vertical position of a center of gravity (C) of the vehicle (2), the method (100) comprises the steps of: • Releasing (105), via the pulling means (7), the first set of wheels (4) in the vertical direction (X); • Simultaneously with the release of said first set of wheels (4), moving (106), via the displacement means (8), said pulling means (7) in said direction

7.

8.

9. horizontal (X) so that said pulling means (7) release said first wheel set (4) in the vertical direction (Y); • Repeat (107) at least once all the steps (101, 102, 103, 104, 105, 106) prior to the step of determining (108) a vertical position of a center of gravity (C) of the vehicle (2). Method (100) according to any one of claims 5 or 6, characterized in that when the support surface (11) is formed by two rollers parallel to each other and free to rotate about their longitudinal axis of rotation (12), the parking brake of the vehicle (2) is activated. Method (100) according to any one of claims 5 to 7, characterized in that when the support surface (11) is formed by two rollers parallel to each other and free to rotate about their longitudinal axis of rotation (12), a vehicle speed (2) is engaged. Method (100) according to any one of claims 5 or 6, characterized in that when the support surface (11) is formed by a flat surface, the parking brake is deactivated and all vehicle (2) speeds are disengaged.

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