Motor vehicle including engine support and chassis

Abstract

The invention relates to a motor vehicle comprising a chassis (2) and an engine support (3) which is directly fastened to a longitudinal member (22) of the chassis (2). According to the invention, the vehicle comprises a connecting part (4) which connects the support to a first structure (21) of the chassis (2), the first structure being located above the longitudinal member (22). In addition, the connecting part (4) comprises a body (40), a first fixing screw (41), a second fixing screw (42), a sliding member (43), and at least one lateral wing (44), the first fixing screw connecting the support to the connecting part (4), the second fixing screw connecting the chassis (2) to the connecting part (4), the sliding member being formed in the body (40) and receiving the first fixing screw and the second fixing screw (41, 42), the at least one lateral wing being arranged along the body (40).

Description

Technical Field

[0001] The invention relates to a motor vehicle comprising a chassis and a support for supporting an engine. Background Art

[0002] In a motor vehicle, the powertrain is located in a known manner in the engine compartment. The powertrain comprises an engine which is held by means of supports on a longitudinal member forming part of the chassis of the vehicle. For example, the engine is held on the longitudinal member by means of a first support placed on one side of the gearbox, a second support placed close to the engine and a third support which is a torque absorbing strut.

[0003] In an embodiment of a vehicle, a support placed on one side of the gearbox serves to hold the engine in place and filter out disturbing vibrations of the engine in order to prevent noise from rising into the vehicle. Disturbing vibrations are caused, for example, by the operation of the gearbox.

[0004] To this end, a support is fixed to the longitudinal members of the vehicle, on which the battery is placed so as to act as an acoustic mass. In this way, the weight of the battery allows the propagation of vibrations to be limited in the support and the chassis, making it possible to reduce the noise generated by these vibrations.

[0005] However, in some models, especially hybrid vehicles, the vehicle's battery is relocated to the trunk due to insufficient space in the engine compartment. Therefore, the battery cannot be used as an acoustic mass.

[0006] Furthermore, the acoustic requirements of hybrid vehicles are more stringent than those of vehicles provided only with a thermal engine. This is because, when the hybrid vehicle is in pure electric operation mode, the thermal engine is switched off and therefore does not generate any noise (referred to as engine noise in order to hide vibration noise). In order to reduce these noises, vibrations have to be minimized.

[0007] In order to solve this problem of disturbing vibrations, hydraulic supports are used, which are used to damp vibrations using hydraulic fluid. However, these hydraulic supports are expensive and sometimes bulky.

[0008] For hydraulic supports, an alternative solution is to increase the rigidity of the support in order to prevent it from vibrating and to place a tie rod at one end of the cantilevered support. However, the technical solution of reinforcement, in particular the addition of a tie rod, often presents problems in terms of the mechanical behavior of the component in the event of a front-end collision.

[0009] The kinematics in the event of a front-end collision must be such that the support acts as a safety device. This means that the support must break, so that the engine is released and slides backwards and downwards along the longitudinal members. In this way, the engine is prevented from entering the area of ​​the passenger compartment where the lower limbs of the passengers are placed. Thus, injuries to the lower limbs of the passengers are prevented.

[0010] The support must be arranged so as not to affect the deformation of the longitudinal members. This is because, in the event of a front-end collision, it is important that the longitudinal members can deform in order to absorb the energy of the impact.

[0011] Overly rigid supports, such as those proposed to overcome vibration problems, run the risk of not breaking during a crash. Thus, in the event of a crash, the engine carried by the support recoils parallel to the longitudinal members and is introduced directly into the area of ​​the lower limbs of the passengers in the passenger compartment.

[0012] In this case, there is a significant risk of injury to the occupant(s) in the vehicle.

[0013] It is therefore necessary to find a technical solution capable of achieving kinematics in the event of an impact that minimizes the risk of injury to the occupant(s) present in the vehicle, while reducing the vibrations in the engine compartment during normal operation of the vehicle. Summary of the invention

[0014] To this end, a first aspect of the invention relates to a motor vehicle comprising:

[0015] - a chassis comprising longitudinal members;

[0016] - A support intended to support the engine in the nacelle; this support is fixed directly to the longitudinal members.

[0017] According to the invention, the vehicle comprises a connecting part which connects the support to a first structure of the chassis, the first structure being located above the longitudinal member. The connecting part comprises a body, a first fixing screw connecting the support to the connecting part, a second fixing screw connecting the chassis to the connecting part, a sliding member produced in the body and receiving the first and second fixing screws, and at least one lateral wing arranged along the body.

[0018] The proposed solution is able to solve the above mentioned problems. In particular, the sliding member present in the connecting part enables at least one of the first fixing screw and the second fixing screw to be released in the event of a frontal impact of the vehicle. In other words, at least one of the fixing screws, in particular the first fixing screw, slides in the sliding member.

[0019] This is because the front end impact initially causes a deformation at the front of the longitudinal member. This deformation pushes the support member (which is directly fixed to the longitudinal member) toward the rear. This displacement of the support member causes the first fixing screw in the sliding member to slide in a direction close to the second fixing screw. In the case where the first structure is part of the chassis (usually a rigid component), the second fixing screw (connecting the connecting member to the first structure) does not move as far as the first fixing screw. At the same time, the support member continues its path toward the rear. Therefore, under the guidance of the movement of the first fixing screw, the connecting member pivots while deforming toward the rear. The fixing member pivots around the second fixing screw.

[0020] With the first structure at a higher level of the longitudinal member, the connecting part pivots rearwardly so that the first fixing screw moves downward again toward the lower region until it moves into abutment with the lower end of the sliding member, which forces the support and the engine to drop downwardly during recoil.

[0021] The deformation of the connecting part is facilitated by the presence of the sliding member. The connecting part deformed in this way acts as a safety device to interrupt the force applied by the support to the first structure of the chassis. In this way, in the event of a front-end collision, the first structure will not be carried backwards by the support and the engine, thereby preventing the first structure from being introduced into the passenger compartment and causing undesirable damage.

[0022] The pivoting and deformation of the connecting parts also enables a portion of the impact energy to be absorbed.

[0023] As a result, the space in the passenger compartment where the lower limbs of the passenger are usually placed is protected. Thus, the risk of injury caused by engine kickback in the event of a front-end impact is reduced.

[0024] Furthermore, the connecting part is provided with at least one lateral wing enabling vibrations to be reduced during normal operation of the vehicle in a direction parallel to the lateral wing.

[0025] The vehicle according to the invention may optionally include one or more of the following features:

[0026] - a first structure of the chassis is an ejection ramp intended to eject the elements contained in the engine compartment in the event of a front-end impact in a direction that moves them away from the ground; normally, when the ejection ramp is installed in the vehicle, it is located at the same level as the lower limbs of the passengers; in this way, the support is fixed under the ramp and, in the event of a front-end impact, is guided to a lower level, allowing the engine to descend so as to avoid the space of the passenger compartment to be protected;

[0027] - the clamping torque applied to the first fixing screw and the second fixing screw is between 19 Nm and 21.5 Nm; the fixing screws clamped in this way can be released in the sliding member in the event of a front end impact;

[0028] - the thickness of the portion of the first structure in contact with the connecting member is equal to or greater than the thickness of the connecting member;

[0029] - the thickness of the portion of the support in contact with the connection part is equal to or greater than the thickness of the connection part; the features of the two previous paragraphs alone or in combination ensure that the support, the connection part and the first structure all have sufficient rigidity to reduce or even eliminate the vibrations propagating in the assembly;

[0030] - the connecting part comprises two parallel lateral wings arranged symmetrically with respect to the central sliding member; the presence of the two lateral wings further reduces vibrations in a direction parallel to these wings; generally, a transverse direction perpendicular to the longitudinal direction of the vehicle;

[0031] The lateral wing or wings are integral with the body and are formed by bending; thus, a simple and low-cost embodiment of the connection part. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Other characteristics and advantages of the invention will become more clearly understood on reading the following detailed description of embodiments of the invention given by way of non-limiting example and illustrated in the accompanying drawings, in which:

[0033] Figure 1 is a perspective view showing the front of an assembly including an engine support, a connecting component, a longitudinal member, and a first structure of a chassis, the assembly being part of a vehicle produced according to an embodiment of the present invention;

[0034] Figure 2 It shows Figure 1 A perspective view of a rear portion of an assembly and a portion of an engine mounted on a support of the assembly;

[0035] Figure 3 yes Figure 1 an enlarged view of the detail designated III in;

[0036] Figure 4 is a perspective view of the connected parts;

[0037] Figure 5 The assembly is shown prior to front-end impact;

[0038] Figure 6 shows the state of the assembly during a front-end impact;

[0039] Figure 7 The assembly is shown after a front-end impact. DETAILED DESCRIPTION

[0040] Structurally and functionally identical elements present in several different figures are given the same numerical or alphanumeric reference signs.

[0041] In the remainder of the description, the axis V will be used to denote the vertical direction, the axis T to denote the horizontal transverse direction or horizontal lateral direction and the axis L to denote the horizontal longitudinal direction. Figures 1 to 7 These three axes are shown in Figure 2.

[0042] The horizontal longitudinal direction L is the direction of movement of the vehicle during forward travel. The terms "front" and "rear" are defined relative to this longitudinal direction L. The vertical direction V is the direction perpendicular to the ground on which the vehicle moves. The terms "top", "bottom", "lower" and "upper" are defined relative to this vertical direction V.

[0043] refer to Figure 1 and Figure 2 , an assembly 1 is part of a vehicle according to the invention, comprising a chassis 2, a support 3 intended to support an engine in an engine compartment, and a connecting member 4 connecting the support 3 to the chassis 2. By using the support 3, the engine 5 is partially fixed to the longitudinal members of the chassis.

[0044] More specifically, the support 3 is fixed directly to the longitudinal members 22 on the one hand and to the send-off ramp 21 on the other hand via connecting means 4. The send-off ramp 21 and the longitudinal members 22 are part of the same chassis 2.

[0045] The support 3 comprises a base 31 having a first side 311 in direct contact with the longitudinal member 22. A fixing screw 310 connects this first side 311 to the longitudinal member 22. The base 31 has a second side 312 parallel to the first side 311. A threaded hole is created at this second side 312 to cooperate with a first fixing screw 41 that attaches the support 3 to the connecting part 4.

[0046] The support 3 further comprises a shock absorber 32, which is produced from rubber, for example, and on which the engine is placed. The shock absorber 32 can absorb and / or attenuate the vibration of the engine in the vertical direction.

[0047] like Figure 1 and Figure 2 As shown, the connecting part 4 is connected to another structure of the chassis, in this case to the delivery ramp 21 located above the longitudinal member 22. A second fixing screw 42 connects the connecting part 4 to the delivery ramp 21.

[0048] The delivery ramp 21 includes a first plate 211 and a second plate 212 , wherein the first plate is slightly inclined relative to a horizontal plane and the second plate is inclined relative to a vertical direction V.

[0049] The ejection ramp 21 is located in front of the space where the legs of the passengers of the passenger compartment are placed. This space is further referred to as the space to be protected. In the event of a front-end collision, the ejection ramp 21 serves to guide the portion 51 of the engine 5 that is positioned oppositely in the upward direction so as to prevent this portion 51 from moving straight forward toward the space to be protected.

[0050] The portion 51 is a member fixed to the engine, such as a power electric box, which has a tendency to separate from the engine 5 during a collision. During a collision, the portion 51 slides on the first plate 211 and then on the second plate 212, which guides the portion towards the cover. The ejection ramp 21 is therefore a component for protecting the passenger compartment.

[0051] As described above, the connecting member 4 connects the second edge 312 of the support 3 to the delivery ramp 21. On the other hand, the first edge 311 of the support 3 is fixed to the longitudinal member 22. In this way, the support 3 is fixed at different positions of the chassis 2, so that the support 3 can be fixed to the chassis 2 more stably. When the support 3 is cantilevered (as in the example shown), it is necessary to stably fix the support to the chassis. Therefore, the support 3 forms a stable base for the engine 5.

[0052] refer to Figure 3 and Figure 4 , the connecting part 4 comprises an elongated body 40, a sliding member 43, and two lateral wings 44 extending along the body 40. The sliding member 43 is in this case a groove formed in the body 40.

[0053] The two lateral wings 44 are perpendicular to the plane containing the body 40. Thus, the cross section of the connecting part 4 is U-shaped. In this case, the lateral wings 44 are parallel to the transverse direction T so as to reduce vibrations and therefore vibration noises in this direction. Thus, the connecting part 4 ensures good acoustic performance.

[0054] In the example shown, the connection part 4 has a symmetrical shape to prevent any risk of loss of acoustic performance in the event of an inverted assembly. The symmetry of the connection part 4 is such that the acoustic performance remains the same whatever the assembly orientation of said part relative to the chassis and the support.

[0055] According to the invention and as in this example, the body has a length L1 between 80 mm and 81 mm. The sliding member has a length L2 between 60 mm and 62 mm. The lateral wings 44 have a height h between 10 mm and 11 mm. Finally, the connecting part 4 has a thickness between 1.9 mm and 2.1 mm. A connecting part dimensioned in this way is compact, enabling it to be integrated in confined spaces.

[0056] In the embodiment of the present invention, the length L1 of the main body is 80 mm, the height h of the lateral wings 44 is 10 mm, and the thickness of the connecting part is 2 mm.

[0057] According to the invention and as in this example, in order to provide sufficient rigidity to all of the support 3, the connection part 4 and the exit ramp 3, the portion 35 of the support 3 in direct contact with the connection part has a thickness greater than the thickness e of the connection part 4. In order to further increase the rigidity of the assembly, the thickness of the portion 25 of the chassis 2 must also be greater than the thickness e of the connection part 4. This increase in rigidity makes it possible to reduce or prevent the vibrations of the components of the assembly. Thus, the vibrations are weakened or even eliminated, and the noise generated by these vibrations will therefore be reduced or eliminated.

[0058] However, the dimensioning described in the previous paragraphs is done in such a way that the additional stiffness provided to the connecting part 4 is not too great in order to facilitate the deformation of said part during a front-end impact. This means that the connecting part 4 must be rigid enough to effectively reduce vibrations, and therefore noise, while at the same time it must be breakable in the event of a front-end impact.

[0059] like Figure 3 and Figure 4 As seen in FIG. 1 , the first fixing screw 41 and the second fixing screw 43 are inserted into the sliding member 43 , and more specifically, into the lower end portion 431 and the upper end portion 432 of the sliding member 43 , respectively.

[0060] The connecting part 4 is in this case oriented such that the longitudinal axis I of the body 40 is inclined towards the rear with respect to the vertical axis V.

[0061] Figures 5 to 7 The kinematics, that is to say the mechanical behavior of each of the components of the assembly 1 in the event of a front end impact, are shown. For the sake of clarity, only the base 31 of the support is shown in these figures.

[0062] exist Figure 5 In the figure, component 1 is in an undeformed initial state before the front end impact. In this initial state, component 1 and Figures 1 to 4 The components described in remain exactly the same.

[0063] exist Figure 6 , the assembly 1 is in an intermediate state at time t during a front-end impact. In this intermediate state, it should be noted that the front portion of the longitudinal member 22 is crushed due to the collision of the vehicle with an object or another vehicle in front of it. The deformation of the longitudinal member 22 causes the support 3, which has remained fixed to the longitudinal member 22, to move rearward. The movement of the support 3 causes the first fixing screw 41 in the sliding member 43 to slide in a direction approaching the second fixing screw 42. In this example, the first fixing screw 41 slides upward.

[0064] exist Figure 7 , the assembly is in the final state at the end of the front-end impact. In this final deformed state, the longitudinal member 22 is further deformed, while the support 3 is located below the delivery ramp 21 and is oriented downwards. The connecting part 4 is deformed and is oriented differently from its orientation when the assembly 1 is in the undeformed initial state. In particular, despite the deformation, the connecting part 4 is inclined towards the front relative to the vertical axis V. In other words, in the final state, the lower end of the connecting part is positioned rearward relative to the upper end of the connecting part.

[0065] In this way, between the intermediate state and the final state, the connecting part 4 pivots from the front to the rear around the second fixing screw 42. This is because, in the case where the delivery ramp 21 is part of the chassis (a very rigid component), the connecting part 4 is fixed to the delivery ramp 21, that is, the second fixing screw 42 moves little or almost not. The support 3 now continues to recoil with the first fixing screw 41 sliding in the sliding member 43. Therefore, the connecting part 4 driven by the first fixing screw 41 can only pivot from the front to the rear around the second fixing screw 42. Therefore, this pivoting causes the first fixing screw 41 to move downwards towards the lower end 431 of the sliding member 43.

[0066] Thus, the support 3 is oriented downwards and carries the engine 5 through it. The engine 5 oriented in this way has less or no risk of penetrating into the passenger compartment at the position where the legs of the passengers are placed. Thus, intrusion into the passenger compartment is limited.

[0067] Furthermore, the deformation and pivoting of the connecting part 4 further absorbs energy during a vehicle collision. The deformation of the connecting part 4 can weaken or even break the connection between the support 3 and the ejection ramp 21. This is intended to prevent the ejection ramp 21 from being carried back into the passenger compartment by the support 3 and the engine 5 towards the rear, causing the risk of injury to the passengers in the vehicle.

[0068] It will be understood that various modifications and / or improvements apparent to those skilled in the art may be made to the different embodiments of the invention described in this specification without departing from the scope of the invention as defined by the appended claims.

Claims

1. A motor vehicle comprising: - a chassis (2) comprising longitudinal members (22); - a support (3) intended to support an engine (5) in the nacelle; the support (3) being fixed directly to the longitudinal member (22); The motor vehicle is characterized in that The motor vehicle comprises a connecting member (4) connecting the support to a first structure (21) of the chassis (2), the first structure being situated above the longitudinal member (22); - The connecting component (4) comprises: --main body (40); a first fixing screw (41) connecting the support member to the connecting member (4); - a second fixing screw (42) connecting the chassis (2) to the connecting member (4); a sliding member (43) produced in the body (40) and receiving the first fixing screw and the second fixing screw (41, 42); and - at least one lateral wing (44), the at least one lateral wing being arranged along the body (40).

2. A motor vehicle according to claim 1, characterized in that The first structure (21) of the chassis is a delivery ramp (21) intended to deliver the elements contained in the nacelle in a direction moving them away from the ground in the event of a front-end impact.

3. A motor vehicle according to claim 1 or 2, characterized in that The clamping torque applied to the first fixing screw (41) and the second fixing screw (42) is between 19 Nm and 21.5 Nm.

4. A motor vehicle as claimed in claim 1 or 2, characterized in that The thickness of a portion (25) of the first structure (21) in contact with the connection member (4) is equal to or greater than the thickness (e) of the connection member (4).

5. A motor vehicle as claimed in claim 1 or 2, characterized in that The thickness of a portion (35) of the support member (3) in contact with the connecting member (4) is equal to or greater than the thickness (e) of the connecting member (4).

6. A motor vehicle as claimed in claim 1 or 2, characterized in that The connecting part (4) comprises two parallel lateral wings (44) which are arranged symmetrically with respect to the central sliding member (43).

7. A motor vehicle as claimed in claim 1 or 2, characterized in that The at least one lateral wing (44) is integral with the body (40) and is formed by bending.

8. The motor vehicle according to claim 6, characterized in that The two parallel lateral wings (44) are integral with the body (40) and are formed by bending.

Images