Suspension device for wheels of motor vehicles

Abstract

A suspension device (1) for a motor vehicle wheel comprises: a support member (2) for the motor vehicle wheel, which can be connected to the motor vehicle structure by means of one or more suspension members (B1, B2); a brake disc (D) which is connected in rotation to the motor vehicle wheel; a brake caliper (3) which is associated with the brake disc (D); and a brake disc cover (4). The brake caliper (3) is formed as a single piece with the support member (2) for the motor vehicle wheel by means of additive manufacturing technology.

Description

Technical Field

[0001] The present invention relates to a suspension device for a wheel of a motor vehicle of the following type, comprising:

[0002] - a motor vehicle wheel support member which can be connected to a motor vehicle structure by means of one or more suspension members,

[0003] - brake discs, which are connected in rotation to the wheels of motor vehicles,

[0004] - a brake caliper, which is associated with the brake disc, and

[0005] - A brake disc cover rigidly connected to the support member and at least partially surrounding the brake disc. Background Art

[0006] Figure Figure 1 and Figure 2 A motor vehicle wheel suspension of the type indicated above is shown, which has already been developed in the past by the same applicant.

[0007] Special reference Figure 1 , which shows a perspective view of a device of known type, the suspension device comprising a support member 2 for a motor vehicle wheel, which support member 2 can be connected to the structure of the motor vehicle by means of a plurality of suspension elements, in particular two pairs of pivoting arms B1, B2. The support member 2 comprises a central perforated portion 26 arranged to receive therein one end of a motor vehicle axle shaft, one end of which is connected in a rotatable manner to a wheel pin, so that the assembly consisting of the wheel pin and the central body of the wheel hub is supported in a rotatable manner by the support member 2. The construction details related to the way in which the pivoting arms B1, B2 are anchored to the structure of the motor vehicle and how the motor vehicle wheel is connected to the support member 2 are not presented here, since these details can be made in any known way and their removal from the drawings makes them quicker and easier to understand.

[0008] As in Figure 1 As shown in , the present device of known type comprises a brake disc D that can be connected in rotation to the wheel of a motor vehicle. According to a reinforcement technology, the disc D (for example made of cast iron or steel) forms part of a brake system of the brake disc type, integrated with the wheel of the motor vehicle.

[0009] The support member 2 also comprises a pair of attachment points 18 arranged for connection with a brake caliper 3 configured to apply a braking action on a motor vehicle by pushing a pair of pads made of friction material against two opposing braking surfaces of a brake disc D.

[0010] exist Figure 1 , Figure 2 In a device of known type shown in , the brake caliper 3 is of fixed type and comprises a body having a pair of elongated side portions 24, each facing the braking surface of the disc D, and a pair of bridge portions connecting the ends of the elongated side portions 24 and defining ventilation openings 19. A pad carrier 17 is arranged between the elongated side portions 24 of the brake caliper 3 and is arranged to cooperate with the braking surface of the brake disc D.

[0011] The elongated side portions 24 have at least two cavities at the respective faces facing the braking surface of the disc D, which are arranged to receive actuators (e.g. hydraulic actuators) configured to exert a thrust action on the brake pads carried by the pad carrier 17 so as to stop them against the braking surface of the disc D and thus exert a braking action on the motor vehicle. The body of the brake caliper 3 may be made of metal, such as aluminium or an aluminium alloy.

[0012] The use of auxiliary systems, such as brake disc covers, to improve the functionality of disc brake systems has long been known.

[0013] Especially as in Figure 2 A perspective view of the brake disc D and the pivot arms B1 and B2 is shown without the brake disc D and the pivot arms B1 and B2. Figure 1 As shown in detail in FIG. 4 , the brake disc cover 4 is rigidly connected to the support member 2 and is configured to at least partially surround the brake disc D.

[0014] The brake disc cover 4 is rigidly connected to the support member 2 of the motor vehicle suspension by means of fastening members 25 and, as a result, is inserted in the assembled state between the support member 2 and the brake disc D. The cover 4 has a central opening 27 which is substantially concentric with the opening 26 of the support member 2, thereby allowing the passage of an axle of the motor vehicle. The main function of the cover 4 is to protect the suspension components from the heat radiated by the brake disc D and to protect the brake disc D from obstruction by foreign bodies such as stones, dirt and grime in general, in particular during driving of the motor vehicle on particularly uneven roads and / or unpaved roads. Summary of the invention

[0015] The object of the present invention is to propose a suspension device for a wheel of a motor vehicle having the characteristics indicated at the beginning of this description, which suspension device has a lighter structure and is cheaper to produce than devices of known type, without resulting in a lower efficiency in performing the function for which it is designed.

[0016] An additional object of the invention is to provide a motor vehicle wheel suspension device of the type indicated at the beginning of this description which, relative to known solutions, improves the cooling of the motor vehicle's braking system and reduces the noise and vibrations resulting from driving the motor vehicle on particularly uneven or unpaved surfaces.

[0017] To achieve the aforementioned objects, the invention relates to a device having the characteristics indicated at the beginning of the present description and further characterized in that the brake caliper is formed in one piece with the supporting member by means of additive manufacturing techniques.

[0018] In this description and the appended claims, the term "additive manufacturing" refers to a method known in the art in which an energy source such as a laser or plasma beam is used to selectively melt powder layers or wires of various sizes of metal or plastic materials to form a part of metal or plastic material layer by layer.

[0019] For example, a device for manufacturing components using additive manufacturing is known from document EP 3 148 784 A1, while European patent application EP 3 470 248 A1 by the same applicant shows an example of the application of the construction technique described above in the field of motor vehicle suspensions.

[0020] Due to the production of a one-piece brake caliper with a motor vehicle wheel support member by means of additive manufacturing techniques, the device according to the invention allows a reduction in the number of components typically used to produce the support function for the motor vehicle wheel and for exerting the braking action on the brake disc, thus producing a single element that is particularly light and economical compared to known solutions.

[0021] Preferably, the brake disc cover is also formed in one piece with the support member and the brake caliper.Thanks to this feature, the device according to the invention is even more effective from the point of view of rationalizing weight and costs, and reduces the noise and vibrations obtained by the movement of the components during the driving of the motor vehicle.

[0022] Still according to a preferred embodiment, the device of the invention comprises an air inlet arranged to uniformly convey an air flow within the device, thereby dissipating the heat generated by the brake disc. Furthermore, the brake disc cover comprises a peripheral portion at least partially surrounding the brake disc, the peripheral portion having a plurality of openings arranged radially along the aforementioned peripheral portion, and the plurality of openings being arranged to direct the air flow towards the brake disc.

[0023] Thanks to these characteristics, the device according to the invention allows effective cooling of the brake disc during driving of the motor vehicle, avoiding overheating of the disc and components connected to it during prolonged braking phases and thus avoiding losses in performance of the braking system due to overheating of the disc and brake pads.

[0024] All the above objects are achieved by a device having these and other characteristics as recited in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Further features and advantages of the present invention will become apparent from the following description, with reference to the accompanying drawings, which are provided by way of non-limiting example only, in which:

[0026] - Already described above Figure 1 , Figure 2 A suspension device for a wheel of a motor vehicle, known and considered herein, is shown.

[0027] - Figure 3 is a perspective view of a preferred embodiment of a device according to the invention which can be associated with a steering drive wheel of a motor vehicle;

[0028] - Figure 4 is Figure 3 Additional perspective views of the details shown in,

[0029] - Figures 5 and 6 Shown is the connection to the additional suspension member Figure 3 and Figure 4 Additional perspective views of the device. DETAILED DESCRIPTION

[0030] In the following description, various specific details are shown for a thorough understanding of the embodiments. The embodiments may be implemented without one or more of the specific details or with other methods, components, materials, etc. In other cases, known structures, construction details, materials, or operations are not shown and described in detail because they can be produced in any known manner and because they do not fall within the scope of the present invention.

[0031] Figures 3 to 6 A preferred embodiment of a suspension device 1 for a wheel of a motor vehicle according to the present invention is shown. Figures 3 to 6 In, using Figure 1 and Figure 2 The same reference numerals are used in connection with the present invention to indicate the various parts which are the same as those of the known type of device previously described.

[0032] In the case shown in the figures, the suspension device 1 can be associated with a front steering and driven wheel suspension; however, the invention is applicable to suspensions and wheels with different architectures, for example associated with non-driven wheels and with motor vehicle rear wheel suspensions.

[0033] As stated previously, for Figure 1 and Figure 2A suspension device of a known type as described in , the device 1 comprises a support member 2 for a wheel of a motor vehicle (the support member 2 being connectable to the structure of the motor vehicle by means of a plurality of suspension members B1, B2), a brake disc D connected in rotation to the wheel of the motor vehicle (in Figure 5 and Figure 6 ), a brake caliper 3 associated with a brake disc D, and a brake disc cover 4 at least partially surrounding the brake disc D.

[0034] According to an essential characteristic of the invention, the brake caliper 3 is formed in one piece with the support member 2 of the wheel by means of an "additive manufacturing" technique. The term "additive manufacturing" refers to a method known in the art in which an energy source such as a laser or a plasma beam is used to selectively melt layers of powders or wires of various sizes of metallic or plastic material, thereby forming a component of metallic or plastic material layer by layer. This production technique is particularly suitable for manufacturing components of particularly complex configurations in a single molding process, wherein said components can traditionally be produced in a plurality of separate pieces and subsequently assembled.

[0035] In the case of the embodiment shown in the accompanying drawings, the brake caliper 3, made in one piece with the support member 2, comprises a body associated with the brake disc D, the body having a pair of elongated side portions 24 facing two opposite braking surfaces of the brake disc D, and a pair of bridge portions connecting the ends of the side portions 24 and defining at least one ventilation opening 19.

[0036] As Figure 1 and Figure 2 As in known arrangements of the type described herein, the pad carrier may be arranged between the elongated side portions 24 of the caliper 3 and arranged to cooperate with the braking surface of the brake disc D. In particular, as in Figure 3 and Figure 4 As shown in , the elongated side portion 24 has two pairs of seats 11 arranged to receive respective actuators configured to exert a thrust action on the pads so as to stop them against the braking surface of the disc D and to carry out a braking action on the vehicle. According to a preferred embodiment, the actuators are of the hydraulic type and the walls defining said seats 11 are made of the same material constituting the body of the caliper 3. Additional construction details related to the pad carriers and the hydraulic cylinders are not presented here, because these details can be implemented in any known manner and also because removing these details from the drawings makes them quicker and easier to understand.

[0037] In particular, refer to Figure 4, which shows a face 13 of the device 1 intended to face the motor vehicle in its assembled state, the device 1 comprises a plurality of structural reinforcement arms 12 arranged in the vicinity of the body of the brake caliper 3. The feature of providing structural reinforcement arms 12 is of particular interest in the context of the present invention due to the fact that the suspension device 1 is made in one piece. Preferably, the lower region of the brake caliper 3 is provided with a first series of structural reinforcement arms 12, in particular in the region between the lateral extensions 24. In a similar manner, the upper region of the brake caliper 3 is also provided with a second series of structural reinforcement arms 12. The structural reinforcement arms 12 comprise opposite ends respectively engaging with a corresponding lateral extension 24 of the brake caliper 2.

[0038] Preferably, the series of structural reinforcement arms is made of a plurality of thin arms having different orientations relative to each other so as to produce a trellis pattern. Some of the structural reinforcement arms 12 include opposite ends respectively engaged with one of the side extensions 24 of the brake caliper 3. In addition, in order to further strengthen the device, some of the reinforcement arms 12 have opposite ends respectively connected to a portion of the brake caliper 3 and to a peripheral area of ​​the brake disc cover 4.

[0039] Since the brake caliper 3 is produced as a single piece with the support member 2 for the wheel, according to the characteristics indicated above, the device 1 according to the invention allows reducing the number of components typically used to produce the support function for the motor vehicle wheel and to exert the braking action on the brake disc, thus producing a single element that is particularly light and at the same time sufficiently robust for the support member for the motor vehicle wheel, as required.

[0040] According to the corresponding Figures 3 to 6 In the particular embodiment of the embodiment shown in , the brake disc cover 4 is also formed in one piece with the support member 2 of the wheel and the brake caliper 3. Conventionally, the brake disc cover is configured to at least partially surround the brake disc in order to protect the brake disc from obstruction by foreign objects, such as stones, dirt and grime in general, in particular when the motor vehicle is traveling on a particularly uneven and / or unpaved road surface.

[0041] refer to Figure 3 and Figure 4 , this embodiment will now be described in more detail.

[0042] The device 1 comprises a central perforated portion 6 arranged to receive therein one end of a load-bearing wheel pin of a motor vehicle axle, so that the assembly consisting of the wheel pin and the central body of the wheel hub is rotatably supported by the device 1. Preferably, in the vicinity of said central perforated portion 6, the central body of the device 1 also has a plurality of weight-reducing and / or ventilation openings 8, as well as a plurality of threaded holes 7 for connecting said support member 2 to an additional suspension device of the motor vehicle.

[0043] According to an important feature of the invention, the device 1 has an air inlet 20 shaped so as to deliver an air flow uniformly inside the device 1 to dissipate the heat generated by the brake disc D during use of the motor vehicle. Preferably, the air inlet 20 is arranged at a side portion of the device relative to the brake caliper 3. The air inlet 20 has a tapered shape, wherein the end portion engages with the brake disc cover.

[0044] In order to effectively cool the disk D, the device 1 further comprises a plurality of openings 5 ​​which are radially and continuously arranged at a peripheral portion of the device 1 surrounding the brake disk D and arranged to direct the airflow entering the air inlet 20 toward the brake disk D.

[0045] Due to the provision of the air inlet 20 and the opening 5, the device 1 according to the invention, in addition to providing the function of supporting the wheel of the motor vehicle associated with the possibility of performing a braking action of the motor vehicle, also provides a thermal function, since the device 1 is configured to effectively cool the brake disc D during the braking phase. Of course, the air inlet 20 and the opening 5 may be oriented and shaped differently than in Figures 3 to 6 As shown in FIG. , while at the same time achieving effective cooling of the heat generated by the barrier between the brake pads carried by the body of the brake caliper 3 and the braking surface of the brake disk D.

[0046] In particular, refer to Figures 4 to 6 , at an interior face 13 intended to face the interior of a motor vehicle in its assembled state, the device 1 comprises an upper attachment point 15 for connection to a ball joint 21 of an upper pivot arm B1 and a lower attachment point 16 for connection to a ball joint 22 of a lower pivot arm B2. The upper attachment point 15 and the lower attachment point 16 each have a main axis extending in an ideal direction to obtain a suspension angle and an axis with specific values ​​in response to the performance required of the vehicle. In the example shown in the accompanying drawings, the upper pivot arm B1 and the lower pivot arm B2 each have a pair of rods shaped so as to produce a triangular pivot arm. A connecting element is arranged at the end of each rod in the form of an elastic bushing intended to be connected in a pivoting manner to the body of the motor vehicle. In the embodiment shown in the accompanying drawings, the elastic bushing has a main axis pointing in a direction substantially perpendicular to the main axis of the ball joints 21, 22.

[0047] refer to Figure 4 , the device 1 comprises an additional attachment point 14 arranged in the vicinity of said upper attachment point 15 for connection to a ball joint 23 of a steering system S associated with the motor vehicle.

[0048] Preferably, the device 1 comprises a first peripheral covering portion 9 and a second peripheral covering portion 10, which are configured to cover the ball joint 23 of the steering system S and the ball joint 21 of the upper pivot arm B1, respectively, thereby protecting the suspension components, the connecting rods of the steering system S and the corresponding joints 21, 23 and the brake disc D from being impacted by stones or dirt during use.

[0049] Thanks to all the features described above, the device 1 according to the invention allows achieving the following advantages.

[0050] Firstly, the caliper being integrated in a single piece with the aforementioned support member allows reducing the number of components typically used to manufacture the aforementioned device (typically the caliper is rigidly connected by means of fastening members at attachment points made on the body of the support member), thus resulting in a structure that is lighter and cheaper to produce.

[0051] Secondly, since additive manufacturing provides the means to also integrate the brake disc cover as a single piece, it is possible to:

[0052] - Further rationalization of weight and costs compared to conventional solutions,

[0053] - Provide a device that exhibits higher rigidity and superior NVH (Noise Vibration Harshness) performance compared to conventional solutions, and

[0054] - Provision is made to also assist in collecting friction material dirt.

[0055] Furthermore, due to its configuration providing an air inlet and a plurality of openings arranged radially and continuously on the peripheral portion of the cover, the device also operates to effectively cool the brake disc during the braking phase.

[0056] Thirdly, thanks to the features indicated above, the device is light and robust enough, which is necessary for a motor vehicle suspension device which has to support the wheel in a stable manner and connect the suspension elements thereto.

[0057] Furthermore, the invention is also directed to a motor vehicle comprising at least two devices according to the invention, for example a pair of devices for non-driven wheels and / or a pair of devices for steered driven wheels.

[0058] Of course, without prejudice to the principle of the invention, the details of construction and of the embodiments may vary widely with respect to those described and illustrated purely by way of example, without departing from the scope of the present invention.

Claims

1. A suspension device (1) for a wheel of a motor vehicle, comprising: - a motor vehicle wheel support member (2) which can be connected to the motor vehicle structure by means of one or more suspension members (B1, B2), - a brake disc (D) connected in rotation to a wheel of the motor vehicle, - a brake caliper (3) associated with said brake disc (D), and - a brake disc cover (4) rigidly connected to the support member (2) and at least partially surrounding the brake disc (D), The brake caliper (3) is formed as a single piece with the support member (2), The suspension device (1) is characterized in that: The brake caliper (3) is formed as a single piece with the support member (2) by means of additive manufacturing technology. The brake disc cover (4) is formed as a single piece together with the support member (2) and the brake caliper (3). The device (1) comprises an air inlet (20) arranged to convey an air flow uniformly within the device (1) so as to dissipate the heat generated by the brake disc (D) during a braking phase performed on the motor vehicle.

2. The suspension device (1) according to claim 1, characterized in that The air inlet (20) is positioned at a lateral portion of the device (1) relative to the brake caliper (3), the air inlet (20) having a tapered shape, wherein an end portion engages with the brake disc cover (4).

3. The suspension device (1) according to claim 1, characterized in that The cover (4) comprises a peripheral portion at least partially surrounding the brake disc (D), the peripheral portion having a plurality of openings (5) extending radially and arranged along the peripheral portion and arranged to direct the air flow towards the brake disc (D).

4. The suspension device (1) according to claim 1, characterized in that The device (1) has a body including a plurality of lightening openings (8) and a central perforated portion (6) arranged to receive the end of a motor vehicle axle therein.

5. Suspension device (1) according to any one of the preceding claims, characterized in that On an inner face (13) facing the interior of the motor vehicle in its assembled state, the device (1) comprises an upper attachment point (15) for connection to a ball joint (21) of an upper pivot arm (B1) and a lower attachment point (16) for connection to a ball joint (22) of a lower pivot arm (B2), the upper attachment point (15) and the lower attachment point (16) each having a main axis extending in a substantially vertical direction.

6. The suspension device (1) according to claim 5, characterized in that The device (1) comprises an additional attachment point (14) arranged in the vicinity of the upper attachment point (15) for connection to a ball joint (23) of a steering system (S).

7. The suspension device (1) according to claim 6, characterized in that The device (1) comprises a first peripheral covering part (9) and a second peripheral covering part (10), which are arranged to cover the ball joint (23) of the steering system (S) and the ball joint (21) of the upper pivot arm (B1), respectively.

8. The suspension device (1) according to claim 4, characterized in that The support member (2) comprises a plurality of holes (7) near the central perforated portion (6) for connecting the support member (2) to an additional suspension member of the motor vehicle.

9. The suspension device (1) according to any one of claims 1 to 4 and 6 to 8, characterized in that: The brake caliper (3) comprises a body mounted in a fixed manner relative to the brake disc (D), wherein the body comprises two elongated side parts (24) each facing a respective braking surface of the brake disc (D).

10. The suspension device (1) according to claim 9, characterized in that The brake caliper (3) comprises at least one pair of seats (11) formed on the body, the at least one pair of seats (11) being arranged to receive corresponding hydraulic cylinders, the hydraulic cylinders being configured to guide the movement of a brake pad carrier arranged in the body and exerting a braking action on the brake disc (D).

11. The suspension device (1) according to claim 9, characterized in that The brake caliper (3) comprises a plurality of structural reinforcement arms (12).

12. The suspension device (1) according to claim 11, characterized in that The plurality of structural reinforcement arms (12) are a plurality of thin arms having different orientations relative to each other so as to produce a lattice-like pattern.

13. The suspension device (1) according to claim 12, characterized in that The plurality of structural reinforcement arms (12) include: - a first series of structural reinforcement arms (12) positioned at the lower region of the brake caliper (3), - A second series of structural reinforcement arms (12) positioned in the upper region of the brake caliper (3).

14. The suspension device (1) according to claim 13, characterized in that The first series of structural reinforcement arms (12) are positioned at the lower region between the two lateral extensions (24) of the brake caliper (3).

15. The suspension device (1) according to claim 13, characterized in that The second series of structural reinforcement arms (12) are positioned at an upper region between the side extensions (24).

16. The suspension device (1) according to claim 12, characterized in that In order to further strengthen the device (1), some reinforcement arms (12) have opposite ends connected to a portion of the brake caliper (3) and to a peripheral area of ​​the brake disc cover (4), respectively.

17. A motor vehicle having at least one pair of suspension devices (1) according to any one of the preceding claims.

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