Inertial suspension for vehicles

Abstract

The invention relates to an inertial suspension (100) for a vehicle, in particular a motor vehicle, the inertial suspension comprising a hydraulic cylinder (103), the hydraulic cylinder comprising a piston separating an upper chamber and a lower chamber, the piston comprising a rod, the inertial suspension (100) being characterized in that the inertial suspension (100) further comprises a connecting piece (104), a first pipe (105) and a second pipe (106) through which hydraulic fluid can pass, the rod comprising a hollow portion, the hollow portion enabling the hydraulic fluid to pass between the upper chamber and the lower chamber via the first and second pipes (105, 106). The inertial suspension (100) is mounted in a wheel rim (120), the wheel rim comprising various parts in its vicinity, such as a brake caliper (130), a transmission shaft (131), a triangular arm (132), a steering link (133) or a brake hose (134).

Description

Technical Field

[0001] The present invention claims the priority of French application N°2000519 filed on January 20, 2020, the content (text, drawings and claims) of which is incorporated herein by reference.

[0002] The invention relates to an inertial suspension for a motor vehicle and a wheel rim comprising such an inertial suspension. The invention also relates to a motor vehicle comprising such a wheel rim on its front axle. Background Art

[0003] In vehicles, suspension systems are necessary due to the unevenness of the surface on which the vehicle travels which causes shocks and vibrations that affect the vehicle and its passengers.

[0004] The suspension system can reduce mechanical fatigue and wear of the vehicle and can improve passenger comfort. In addition, the suspension system is essential to maintain contact between the vehicle wheels and the ground in the presence of uneven ground. Contact between the vehicle wheels and the ground is necessary for the driving stability of the vehicle. Traditionally, the vehicle wheel suspension includes mechanical connections, springs and buffers between the non-suspension mass and the suspension mass. The non-suspension mass typically includes the wheel and the driving parts or brake parts for driving the wheel. The suspension mass typically includes the body of the vehicle and its powertrain and any other components of the vehicle fixed to the body.

[0005] The weight of the vehicle is a parameter that plays an important role in the optimization of the suspension system. The high weight of the vehicle results in a greater inertia, which can allow (especially in terms of passenger comfort) a better optimization of the performance of the suspension system. In fact, a high inertia makes the mass movements related to ground irregularities more difficult and promotes a greater filtering of shocks and vibrations. However, considering the very important influence of weight on other vehicle properties (for example the fuel consumption of the vehicle), it is difficult to imagine weighting the vehicle to better optimize the performance of the suspension system.

[0006] The concept of an inertial device (also called an "inerter") was introduced by Malcolm C. Smith in his article "Synthesis of mechanical networks: The inerter" (IEEE Transactions on Automatic Control, Vol. 47, n°10, 2002, pp. 1648-1662) by means of an analogy between electrical and mechanical systems. The advantages of integrating such an inerter in a passive vehicle suspension are described in an article entitled "Perfomance benefits in passive vehicle suspensions employing inerters" (Malcolm C. Smith et al., 2004, Vol. 42, n°4, pp. 235-257).

[0007] The inertial device can be implemented as a mechanical system (the mechanical system has, for example, an inertial flywheel mounted on a rack) or as a hydraulic circuit. The inertial device integrated in the suspension (also called "inertial suspension") produces an effect similar to the increase in the inertia of the suspended mass.

[0008] From document CN105276060A a hydraulic inertia device with a variable inertia coefficient for a suspension is known. The device comprises a helical double pipe for providing two fluid passage circuits. The double pipe is connected to the top chamber and the bottom chamber of a hydraulic cylinder, the piston of which is moved by the movement of the suspension. A regulating valve is provided for controlling the passage of the fluid through one or the other passage circuit in order to modify the inertia coefficient of the device.

[0009] Document FR3073174A1 describes a hydraulic buffer for a motor vehicle suspension, comprising a main piston that moves during the movement of the suspension and separates two main chambers, an inertial fluid column and two auxiliary chambers connected to the main chamber. The auxiliary chambers include a return spring and are separated by a floating piston having a balanced leakage orifice. A bypass duct is also provided in the hole for receiving the floating piston. The floating piston is connected to an inertial piston that separates two inertial chambers, which are connected to each other by the fluid column.

[0010] These inertial suspensions have several disadvantages. In fact, they comprise a greater number of parts than the hydraulic suspensions commonly used in motor vehicles. Therefore, the installation of an inertial suspension proves to be complicated or even impossible for some vehicles, since there is not enough volume in the axle environment of the motor vehicle to accommodate such a suspension. Summary of the invention

[0011] The object of the present invention is therefore to overcome the disadvantages of the prior art by providing an inertial suspension which simplifies its installation in a motor vehicle.

[0012] To this end, the present invention thus relates in its broadest sense to an inertial suspension for a vehicle, in particular a motor vehicle, comprising a hydraulic cylinder comprising a piston separating an upper chamber and a lower chamber, the piston comprising a rod, the inertial suspension being characterized in that it also comprises a first duct and a second duct through which a hydraulic fluid can pass, the rod comprising a hollow portion which enables the hydraulic fluid to pass between the upper chamber and the lower chamber via the first and second ducts.

[0013] Preferably, the upper chamber is coupled to an upper accumulator, and the lower chamber is coupled to a lower accumulator.

[0014] Advantageously, the inertial suspension further comprises a connecting member, the connecting member comprising a first concave cavity and a second concave cavity, the first concave cavity coupling the first conduit with the second conduit, and the second concave cavity coupling the second conduit with the lower chamber.

[0015] Preferably, at least one load loss buffer is arranged between the upper chamber and the upper accumulator and / or between the lower chamber and the lower accumulator.

[0016] According to a preferred embodiment, the first and second conduits have a first substantially cylindrical outer shell and a second substantially cylindrical outer shell, respectively, the first outer shell having a first inner diameter and the second outer shell having a second inner diameter.

[0017] Preferably, each of the first housing and the second housing has an opening.

[0018] Preferably, a first inner diameter of the first outer shell is greater than a second inner diameter of the second outer shell.

[0019] The present invention also aims to provide a wheel rim of a vehicle, characterized in that the wheel rim comprises an inertial suspension having any one of the above-mentioned characteristics.

[0020] Preferably, the wheel rim comprises an inner hollow portion, the first duct and the second duct being arranged in the inner hollow portion.

[0021] The invention also relates to a vehicle, characterized in that it comprises a front axle comprising a wheel rim according to the invention arranged at the left front part and a wheel rim according to the invention arranged at the right front part. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention will become more apparent from a reading of the detailed description given in a non-limiting manner and of the accompanying drawings in which:

[0023] Figure 1 shows a schematic perspective view of a left front wheel rim of a motor vehicle, the left front wheel rim comprising an inertial suspension according to an embodiment of the invention;

[0024] Figure 2 Shows Figure 1 A perspective view of the inertial suspension shown above;

[0025] Figure 3 yes Figure 2 A cross-sectional view of a portion of the inertial suspension is shown above. DETAILED DESCRIPTION

[0026] refer to Figure 1 , schematically shows a left front wheel rim 120 of a motor vehicle, which includes an inertial suspension 100 according to an embodiment of the present invention. The rim 120 includes various parts commonly found in the vicinity of a wheel rim of a motor vehicle (such as a brake caliper 130, a transmission shaft 131, a triangle 132, a steering link 133 or a brake hose 134). The inertial suspension 100 includes an upper accumulator 101, a lower accumulator 102, a hydraulic cylinder 103, a connecting housing 104, a first pipe 105 and a second pipe 106. The first and second pipes 105, 106 are arranged in a manner similar to the embodiment of the present invention. Figure 2 The cup for the suspension spring 140 is integral with the hydraulic cylinder 103. The suspension spring is not shown in any of the accompanying drawings. Figure 3, it is seen that the hydraulic cylinder 103 comprises in particular an upper chamber 107, a lower chamber 108 and a piston 112. A hydraulic fluid (not shown) passes in the inertial suspension 100 between the upper chamber 107 and the lower chamber 108. The hydraulic cylinder 103 also comprises a rod 109 which comprises a hollow portion and which can move in translation in the body 110 of the hydraulic cylinder 103. When the rod 109 moves towards the upper chamber 107, the hydraulic fluid can pass in the inertial suspension 100 along a circuit starting from the upper chamber 107, this starting point being arbitrarily chosen in order to describe the path of the hydraulic fluid in the inertial suspension 100, the hydraulic fluid then passing on the one hand towards the upper accumulator 101 and on the other hand towards the first duct 105 by means of a first hose (not shown). The hydraulic fluid then passes through a first recess (not shown) of the coupling housing 104 which couples the first duct 105 with the second duct 106. A first damper (not shown) forming a load loss is arranged in the first cavity and between the first pipe 105 and the second pipe 106. Thus, the hydraulic fluid passes in the first pipe 105, then passes through the first damper forming a load loss, and then travels in the second pipe 106. The hydraulic fluid leaves the second pipe 106 and then passes again in the connecting housing 104 in the second cavity 111. The second cavity 111 connects the lower accumulator 102 to the second pipe 106 on the one hand and to the lower chamber 108 on the other hand. A second damper (not shown) forming a load loss is arranged in the second cavity 111 between the lower accumulator 102 and the second pipe 106 and between the lower accumulator 102 and the lower chamber 108. The hydraulic fluid ends its travel in the lower chamber 108. When the rod 109 moves toward the lower chamber 108, the hydraulic fluid travels a path opposite to the path described when the rod 109 moves in the direction of the upper chamber 107. The first and second ducts 105, 106 are configured for integration in the inner volume of the wheel rim 120. The first and second ducts 105, 106 respectively have, on the one hand, a substantially cylindrical first outer shell and a substantially cylindrical second outer shell and, on the other hand, a first serpentine bend and a second serpentine bend. The cylindrical first outer shell of the first duct 105 thus has a first inner diameter D1, the axis of which substantially coincides with the axis of the wheel rim 120. In a preferred embodiment, the cylindrical first outer shell of the first duct 105 has an opening, that is to say, the first duct 105 passes through the cylindrical first outer shell over a first angle A1 of less than 360°. In a particular embodiment, the first angle A1 has a value between 180° and 220°.In this preferred embodiment, the cylindrical second shell of the second duct 106 has a second inner diameter D2, the axis of which also substantially coincides with the axis of the wheel rim 120, and the cylindrical second shell of the second duct 105 also has an opening, that is, the second duct 105 passes through the cylindrical second shell at a second angle A2 less than 360°. In a particular embodiment, the second angle A2 has a value between 180° and 200°. In another particular embodiment, the first angle A1 and the second angle A2 are substantially equal. The first duct 105 is formed by a tube having a diameter d1, which is relatively small relative to the first inner diameter D1, for example 1 / 10 to 1 / 20 of the first inner diameter. The second duct 106 is likewise formed by a tube having a diameter d2, which is relatively small relative to the second inner diameter D2, for example 1 / 10 to 1 / 20 of the second inner diameter. The first inner diameter D1 of the first duct 105 is greater than the second inner diameter D2 of the second duct 106. The particular configuration of the first and second ducts 105, 106 is advantageous in that it enables a compact inertial suspension 100 to be obtained, which can thus be easily mounted in the internal volume of a wheel rim 120 of a motor vehicle. In addition, the configuration of the rod 109 enables the hydraulic cylinder 103 of the inertial suspension 100 to be housed in the internal volume of a suspension spring supported by the cup of the suspension spring 140. In this way, the inertial suspension 100 according to the invention has an increased compactness.

Claims

1. An inertial suspension (100) for a vehicle, the inertial suspension comprising a hydraulic cylinder (103), the hydraulic cylinder comprising a piston (112) separating an upper chamber (107) and a lower chamber (108), the piston (112) comprising a rod (109), characterized in that: The inertial suspension (100) further comprises a first pipe (105) and a second pipe (106) through which hydraulic fluid can pass, the rod (109) comprises a hollow portion, the hollow portion enables the hydraulic fluid to pass between the upper chamber (107) and the lower chamber (108) via the first pipe (105) and the second pipe (106), the inertial suspension (100) further comprises a connecting member (104), the connecting member comprises a first concave cavity and a second concave cavity (111), the first concave cavity connects the first pipe (105) with the second pipe (106), and the second concave cavity (111) connects the second pipe (106) with the lower chamber (108).

2. The inertial suspension (100) according to claim 1, characterized in that: The upper chamber (107) is connected to the upper accumulator (101), and the lower chamber (108) is connected to the lower accumulator (102).

3. The inertial suspension (100) according to claim 2, characterized in that: At least one load-loss buffer is arranged between the upper chamber (107) and the upper accumulator (101) and / or between the lower chamber (108) and the lower accumulator (102).

4. The inertial suspension (100) according to any one of the preceding claims, characterized in that: The first conduit (105) and the second conduit (106) respectively have a first substantially cylindrical outer shell and a second substantially cylindrical outer shell, the first outer shell having a first inner diameter (D1), and the second outer shell having a second inner diameter (D2).

5. The inertial suspension (100) according to claim 4, characterized in that: Each of the first housing and the second housing has an opening.

6. The inertial suspension (100) according to claim 4, characterized in that: The first inner diameter (D1) of the first housing is greater than the second inner diameter (D2) of the second housing.

7. A wheel rim (120) of a vehicle, characterized in that: The wheel rim (120) comprises an inertial suspension (100) according to any one of claims 1 to 6.

8. The wheel rim (120) according to claim 7, characterized in that The wheel rim (120) comprises an inner hollow portion, and the first duct (105) and the second duct (106) are arranged in the inner hollow portion.

9. A vehicle, characterized in that: The vehicle comprises a front axle comprising a wheel rim (120) according to claim 7 or 8 arranged at the left front part and a wheel rim (120) according to claim 7 or 8 arranged at the right front part.

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