torsional damper

Abstract

A damper (1) comprising a hub (2) having a longitudinal axis (A), the hub defining an inner portion (2'), designed to be connected to a hub (3) hauled by a shaft rotating about said axis (A), an outer portion (2''), defining an engagement portion (5) designed to cooperate with an annular transmission element, and an intermediate portion (2'''), connecting said inner and outer portions (2'', 2'), the damper (1) comprising an inertia ring (12) operatively connected to one of said portions (2', 2'', 2''') so as to dampen torsional oscillations transmitted by said shaft to said annular transmission element, the hub (2) defining a plurality of openings (15), the damper (1) comprising a ventilation system (16) configured to force air to flow towards said inertia ring (21) via said openings (15).

Description

[0001] Cross-reference to related applications This patent application claims priority to Italian patent application No. 102024000004345, filed on February 28, 2024, the entire disclosure of which is incorporated herein by reference. Technical Field

[0002] This invention relates to a damper, particularly a torsional damper.

[0003] This invention is preferably, but not exclusively, applied in the automotive industry. Reference will be made to this application by way of example only below. Background Technology

[0004] It is well known that the drive shaft of an internal combustion engine is subjected to torsional vibration due to the periodic stresses caused by combustion in the cylinder. This vibration is particularly pronounced when the engine is started and at low speeds, and in the presence of specific constructive solutions, such as, for example, the use of a dual-clutch transmission or a start-stop system.

[0005] Torsional vibration is transformed into irregularities in the rotation of the drive pulley of the accessory transmission device, which are transmitted to the accessory through the transmission belt, thus subjecting the transmission belt to periodic tensile vibration.

[0006] Therefore, it is known in the automotive industry that the amplitude of torsional vibrations of a drive shaft is reduced by using filtering components (such as torsional dampers), which are distinguished based on their operating principles (i.e., based on the means used to dampen vibrations).

[0007] In the past, many of the friction dampers used in motor vehicle engines were for torsional vibrations. In a broad sense, this included flywheels, which were rotated by the drive shaft through a friction coupling. Due to their high moment of inertia, flywheels tend to exhibit a constant rotational speed, thus damping any torsional vibrations of the drive shaft through friction.

[0008] For applications requiring high specific power and for use in motor vehicles, dampers using elastic materials or viscoelastic fluids as damping devices are provided, operating on a principle similar to that described above. In the case of viscoelastic fluid dampers, the connection between the drive shaft and the flywheel is achieved by inserting a viscous device, typically a silicone fluid.

[0009] Optionally, the torsional damper can be coupled to a filter pulley of various types, such as those known from EP3271616 A1.

[0010] During their use, dampers tend to heat up, making it necessary to reduce the use of dampers or requiring designs that increase their size, weight, and therefore cost.

[0011] The solution is known in which the cooling fin is obtained from and carried by a portion of the damper; however, it is not configured to allow for adequate cooling.

[0012] Other blade solutions are known, however, they are particularly expensive and difficult to manufacture.

[0013] The purpose of this invention is to provide a torsional damper that can solve the above-mentioned technical problems in a simple and economical way.

[0014] In particular, the aim is to provide a damping assembly that allows the damper to remain within a predetermined temperature range without increasing its size, weight, and cost as is the case in known systems. Summary of the Invention

[0015] The aforementioned objective is achieved by a torsional damper and a filter assembly as claimed in the appended claims, which are integral parts of this specification. Attached Figure Description

[0016] The invention will be best understood by reading the following detailed description of preferred embodiments with reference to the accompanying drawings, which are provided by way of non-limiting example, wherein: Figure 1 This is a perspective view of the damper according to the present invention; Figure 2 It is based on Figure 1 A cross-sectional view of line II-II of the damper; Figure 3 yes Figure 1 Exploded perspective view of the damper; and Figure 4 yes Figure 1 An enlarged perspective view of a portion of the damper. Detailed Implementation

[0017] The attached figure shows a damper 1 used in automobiles.

[0018] The damper 1 is coaxial with the longitudinal axis A and essentially includes a hub 2. In a disc-shaped embodiment, the hub 2 includes an outer portion 2', an inner portion 2'', and a middle portion 2'''. The outer portion 2' is configured to mate with an annular connecting element such as a toothed belt. The inner portion 2'' is radially inside the outer portion 2'. The middle portion 2''' connects the outer portion 2' and the inner portion 2'' to each other.

[0019] The outer part 2' is designed for a rotating shaft (not shown), which is coaxial with axis A and forms part of the vehicle's powertrain (not shown).

[0020] Advantageously, the hub 2 described above is manufactured as a single piece, that is, it is integral.

[0021] In detail, the outer portion 2' includes an outer cylindrical wall 4, which is coaxial with axis A and defines a mating portion 5. The mating portion 5 is provided with a connecting profile configured to mate with the aforementioned annular transmission element. For example, the connecting profile 5' is a multi-V profile for relative toothed belts.

[0022] The outer portion 2' also includes an outer radial wall 6, which is configured to extend radially toward the longitudinal axis A from one of the axial ends of the outer cylindrical wall 4.

[0023] The inner portion 2'' includes an inner radial wall 7 that extends radially from the hub 3 on a side axially opposite to the outer radial wall 6.

[0024] The middle portion 2''' is configured to connect the outer radial wall 6 and the inner radial wall 7, and in particular, includes an inner cylindrical portion 8 connected to the outer radial wall 6 and the inner radial wall 7 via corresponding connecting portions 8', 8''.

[0025] Therefore, hub 2 defines space 11, which is axially defined by outer radial wall 6 and opens on opposite sides and is radially defined by outer cylindrical wall 4 and inner cylindrical wall 8.

[0026] The damper 1 includes a damping module 10, which is housed in the space 11 and configured to cause torsional oscillation at the damping hub 2.

[0027] In the embodiments described herein, the damping module 10 includes an inertia ring 12, which is housed in a space 11 and has an annular shape and is made of a metallic material having a predetermined shape and weight.

[0028] The inertia ring 12 is connected to the hub 2 to allow torsional oscillation between the damping hub 2 and the annular transmission element connected via the engagement portion 5.

[0029] In particular, in the embodiments described herein, the damper 1 includes a connecting portion 13 made of an elastic material (advantageously a polymer and / or an elastomer and / or a plastic material) configured to connect the inertia ring 12 to the outer cylindrical wall 4.

[0030] Alternatively, although this solution is not shown herein, the damping module 10 may include a housing designed to support a viscous fluid, and an inertial ring 12 may be placed within the housing to operatively connect it to the hub 2 to allow for the aforementioned damping of torsional oscillations.

[0031] Advantageously, the hub 2 defines a plurality of openings 15 configured to allow air to flow through the hub 2 into the space 11.

[0032] Preferably, the openings 15 are formed in the outer radial wall 6. Advantageously, they are arranged circumferentially around the longitudinal axis A, and more specifically, they are equidistant from each other at an angle around the axis A.

[0033] Advantageously, these openings 15 are quadrilateral, and more specifically, rectangular, wherein the larger edge of the rectangle faces the circumferential direction.

[0034] The damper 1 is preferably provided with a ventilation system 16, which is provided with one or more blades 19 configured to force air through an opening in the hub 2 to flow toward or out of the damper module 10.

[0035] Advantageously, the ventilation system 16 includes a plurality of blades 19, wherein at least one blade is used for each opening 15.

[0036] Advantageously, the blade 19 is configured to have an inclination relative to the outer radial wall 6. More specifically, the blade 19 extends relative to the smaller edge of the aforementioned opening 15.

[0037] In the embodiments described herein, each opening 15 accommodates a pair of blades 19, with one blade on each smaller side of the opening 15. Specifically, the blades are angled opposite to each other, i.e., one blade faces the space 11 while the other blade faces the external space on the side opposite to the space 11.

[0038] Advantageously, the ventilation system 16 can be selectively fixed to the hub 2. In detail, in the embodiment shown herein, the blade 1 is carried by an auxiliary element 17 configured to be selectively fixed to the outer radial wall 6.

[0039] Specifically, the auxiliary element 17 and the plurality of blades 19 are manufactured as a single piece and have an annular shape such that when fixed thereto, its axial direction faces the outer radial wall 6.

[0040] In detail, the auxiliary element 17 defines a plurality of openings 18 having a shape similar to (in particular identical to) that of the openings 15 and being coaxial with them. The openings 18 are provided with the aforementioned blades 19.

[0041] Therefore, in the embodiment described herein, opening 18 has a similar shape to opening 15 and is provided with blades 19 extending circumferentially from opposite sides relative to each other. Specifically, they are thus supported by the smaller edges of the rectangular shape of each opening 18.

[0042] As described above, the auxiliary element 17 can be selectively fixed to the hub 2 by the fixing system 20 so that the blade 19 can be placed through the openings 18, 15.

[0043] In detail, the fixing system 20 includes a snap-fit ​​mechanism 21. Advantageously, the snap-fit ​​mechanism includes at least one resilient wing configured to insert into and integrate the auxiliary element 17 with the hub 2. Specifically, the at least one wing is supported by one edge of the opening 18 and is sized to snap into the opening 15, thereby providing axial preload between the auxiliary element 17 and the hub 2 (i.e., its outer radial wall 6).

[0044] More specifically, according to the embodiment described herein, the snap-fit ​​mechanism 21 includes a pair of wings supported by the larger edge of the opening 18 and particularly in its middle.

[0045] like Figure 4 As best shown, each blade 19 advantageously includes a main wall 19', which is preferably flat.

[0046] In particular, as described above, the main walls 19' are inclined in opposite directions relative to the longitudinal axis A, and in particular, they have the same degree of inclination in opposite directions.

[0047] Advantageously, for each opening 18 / 15, one blade 19 includes a main wall 19' extending directly from the auxiliary element 17, while the other blade extends from a protrusion 19'' protruding from the auxiliary element 17.

[0048] The protrusion 19'' extends axially along axis A to allow the blade 19 to extend within the opening 15 / 18. Specifically, the extension of the protrusion 19'' engages with one edge of the opening 15, thus contacting the outer radial wall 6 to function as a circumferentially limiting stop.

[0049] Depending on the required design needs, the auxiliary element 17 can be made of metal or plastic / polymer materials.

[0050] In detail, although this is not shown in the figure, the damper 1 can be part of the filter assembly, that is, it can be connected to the filter pulley (not shown), which is connected, for example, on the same side as the hub 2 or on the opposite side thereto.

[0051] The operation of the damper embodiment according to the present invention will be disclosed below.

[0052] During the operation of damper 1, the torque supplied to hub 2 by the rotating shaft is typically transmitted to engagement portion 5. Any torsional oscillations transmitted to hub 2 are absorbed by damping module 10.

[0053] During operation, i.e., during the rotation of the damper 1 about axis A, the blade 19 is configured to draw air into the damping module 10 through the opening 15.

[0054] For the reasons stated above, the advantages of the damper according to the present invention are obvious.

[0055] Because the damper 1 disclosed herein can effectively cool the inertia ring to reduce its design size, thereby reducing weight and size to allow it to be used for as long as possible.

[0056] By reducing weight and size, manufacturing costs and time are significantly reduced. Furthermore, it is clear that keeping the damper at a lower temperature prevents wear during prolonged use.

[0057] Furthermore, the special arrangement of the blades and openings allows a large amount of air to be drawn into the inertial ring. The shape of the blades is also optimized to maximize this airflow and allow it to be drawn in both directions.

[0058] The fact that the blades are placed on separable elements that can be fixed to the hub facilitates the production of dampers, as they can be produced using different manufacturing methods, thus saving and optimizing production time.

[0059] Furthermore, it facilitates the assembly and possible replacement of one of the two components of the damper.

[0060] Furthermore, the mechanical snap-fit ​​connection is easy to use and safe, and can be easily removed for replacement or inspection.

[0061] Furthermore, the fact that one of the blades extends from the protrusion that serves as a circumferential limiting stop facilitates the installation of auxiliary elements so as to match the opening and blades at the correct angular position.

[0062] Finally, the damper according to the invention can be obviously modified and modified, but this does not exceed the scope of protection set forth in the appended claims.

[0063] Obviously, as mentioned above, the damper can be isolated on the rotating shaft or connected to the filter pulley or other separating element.

[0064] Furthermore, as mentioned above, the damper can be an elastic ring damper or a viscous damper.

[0065] Furthermore, the openings or blades disclosed herein may have different shapes or be different in number from those described above.

[0066] Furthermore, auxiliary components may be absent, and the blades may be integrated into the hub itself, or they may be fixed to the hub 2 in different ways, such as by threaded elements, by welding, or by interference.

Claims

1. A damper (1) comprising a hub (2) of a longitudinal axis (A), the hub (2) defining an inner portion (2') rotatable by a bearing about the axis (A), an outer portion (2'') defining a mating portion (5) capable of engaging with an annular transmission element, and an intermediate portion (2''') connecting the inner and outer portions (2'', 2'), the damper (1) comprising a damping module (10) operably connected to one of the portions (2', 2'', 2''') to dampen torsional oscillations transmitted from the axis toward the annular transmission element, the hub (2) defining a plurality of openings (15), the damper (1) comprising a ventilation system (16) having one or more blades (19) associated with each of the openings (15), the blades (19) being configured to force airflow through the openings (15) toward or from the damping module (10).

2. The damper according to claim 1, wherein, The outer portion (2') includes an outer radial wall (6), and the opening (15) is formed through the outer radial wall (6).

3. The damper according to claim 1 or 2, wherein the opening (15) is circumferentially positioned around the longitudinal axis (A).

4. The damper according to claim 3, wherein, The openings (15) are equidistant from each other at an angle.

5. The damper according to any one of the preceding claims, wherein, Each of the openings (15) is associated with two blades (19), one of which is inclined relative to the longitudinal axis (A) in the opposite direction to the other.

6. The damper according to claim 5, wherein, The blades (19) have the same inclination relative to the longitudinal axis (A) in the opposite direction relative to the other.

7. The damper according to claim 5 or 6, wherein, The opening (15) has a rectangular shape, and the blades (19) are associated with the edges of the smaller extensions of the opening (15).

8. The damper according to claim 7, wherein the longest edge of the opening (15) faces circumferentially along the axis (A).

9. The damper according to any one of the preceding claims, wherein, The blade (19) passes through the opening (15).

10. The damper according to any one of the preceding claims, wherein, The blade (19) is carried by an auxiliary element (17) that can be selectively connected to the hub (2).

11. The damper according to any one of the preceding claims, wherein, The damping module (10) includes an inertial ring (12) connected to the hub (2) via a viscous fluid system or via an elastic connector (13).

12. A damping assembly comprising a filter pulley operably connected to the damper (1) according to any one of the preceding claims.

13. A vehicle system comprising a damper (1) according to any one of claims 1 to 11 and / or a damping assembly according to claim 12.

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