Improved damper group

Abstract

A damping assembly (F) includes a filter pulley (1); the filter pulley (1) includes a hub (2) designed to be fixed to an axle rotating about a longitudinal axis (A); a rim (3) coaxially mounted on the hub (2) and thus freely rotating on the hub (2); at least one filter assembly operatively inserted between the rim (3) and the hub (2); the rim (3) defining a first annular wall (5″) having a profile (6) configured to engage an annular transmission element of a vehicle system; the first annular wall (5″) The damping assembly (F) is supported by a connecting wall (9) operatively connected to the filter assembly; the damping assembly (F) includes a torsional damper (30) supported by the hub (2) and housed in a space (35) defined by the hub (2), the connecting wall (9), and the first annular wall (5''); the connecting wall (9) defines a plurality of openings (40) configured to allow air to pass through the connecting wall (9) and the space (35).

Description

[0001] Cross-referencing related applications This patent application claims priority to Italian Patent Application No. 102023000026472, filed on December 12, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to an improved damping assembly, preferably for use in the crankshaft pulley of an accessory drive system in an internal combustion engine. Background Technology

[0003] As is well known, the drive shaft of an internal combustion engine is subjected to torsional vibration due to the periodic stress generated by combustion in the cylinders. This vibration is particularly pronounced during engine start-up, low-speed operation, and in models with specific structures such as dual-clutch transmissions or start-stop systems.

[0004] Torsional vibration causes irregular rotation of the drive pulley of the auxiliary transmission device. The torsional vibration is transmitted to the accessory through the drive belt, so the drive belt is subjected to periodic tension changes.

[0005] Therefore, in the automotive industry, filter components equipped with dampers are commonly used in conjunction with filter pulleys to reduce the amplitude of torsional vibrations in drive shafts; these components are distinguished according to their damping principles (i.e., according to the medium used to dampen vibrations).

[0006] In the past, automotive engines have widely adopted torsional friction dampers. In a broad sense, this type of damper includes a flywheel, which is driven to rotate by the drive shaft through a clutch structure. The flywheel has a large moment of inertia and tends to maintain a constant speed, thereby attenuating the torsional vibration of the drive shaft through friction.

[0007] For high-power-density models and various automotive equipment, vibration dampers using elastic materials or viscoelastic fluids as damping media are also employed, with working principles similar to those of the aforementioned dampers. For viscoelastic fluid vibration dampers, the drive shaft and flywheel are coupled by sandwiching a viscous medium (usually silicone oil).

[0008] The fluid is contained within a cavity defined by a cup-shaped component and a disk rigidly connected to the cup-shaped component, which also houses the rotating component / flywheel.

[0009] For filter pulleys, there are many forms in the prior art, such as the structure disclosed in EP 3271616 A1.

[0010] During operation, the rotating components heat the fluid inside the cavity, which limits the operating conditions of the shock absorber or forces the design to increase its size and weight, ultimately leading to increased costs.

[0011] For example, DE1020108691A1 contains a design where heat dissipation fins are installed on the outer wall of the cup-shaped component, which facilitates heat exchange with the external environment when the component rotates. However, it is clear that this design increases the manufacturing cost of the vibration damper and also increases its noise, thereby reducing energy efficiency.

[0012] Another known structure (e.g., shown in DE102021106830B3) involves creating a bladed through-hole on the filter pulley near the damper, configured to guide airflow towards the cup-shaped portion of the damper for cooling. In this case, machining the blades would increase the manufacturing cost of the damping assembly and increase noise.

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

[0014] Specifically, the aim is to provide a damping component that allows the damper to be kept within a predetermined temperature range without increasing its size, weight, and cost as in existing systems. Summary of the Invention

[0015] The above objective is achieved by a damping assembly according to the appended claims (which are an integral part of this specification). Attached Figure Description

[0016] The invention will be best understood by reading the following detailed description of preferred embodiments, provided as non-limiting examples and in conjunction with the accompanying drawings, in which: Figure 1 This is a perspective view of the filter assembly according to the present invention; Figure 2 yes Figure 1 An exploded perspective view of the filter component; Figure 3 yes Figure 1 First cross-sectional perspective view of the filter component; Figure 4 yes Figure 1 First diameter cross-sectional view of the middle filter assembly; Figure 5 yes Figure 1 Second diameter cross-sectional view of the filter assembly; and Figure 6 yes Figure 1 A second cross-sectional perspective view of the filter component. Detailed Implementation

[0017] Figures 1 to 4A filter assembly F is shown, which includes a filter pulley 1. The filter pulley 1 includes a hub 2 with axis A, which is designed to be connected to a shaft (not shown), such as the crankshaft of an internal combustion engine, and an annular rim 3, which is coaxial with the hub 2 externally and supported by the hub 2 by a support device 4 so that it can rotate freely.

[0018] The wheel rim 3 includes first and second annular portions 5', 5'', each annular portion having a profile 6 designed to engage with an annular drive element of the vehicle system (e.g., a multi-ribbed belt (not shown) of an accessory drive).

[0019] In particular, the first and second annular portions 5', 5'' are arranged at different radial distances from the hub 2 and are connected to each other by a connecting wall 9, which is substantially radial relative to the axis A.

[0020] The rim 3 integrally supports the cup-shaped element 7, which includes: an outer cylindrical wall 7' configured to contact and engage with the first annular portion 5'; a radial annular wall 7'', which advantageously has a shaped form and extends from the outer cylindrical wall 7' toward the hub 2; and an inner cylindrical wall 7''' connected to the side of the radial wall 7'' opposite to the outer cylindrical wall 7'.

[0021] Advantageously, the inner cylindrical wall 7''' contacts and engages with the aforementioned support device 4.

[0022] The rim 3 integrally supports the closure element 11, which includes an outer cylindrical wall 11' having an axis A; and a radial annular wall 11'', advantageously having a shaped form and extending from the wall 11' towards the hub 2. In the embodiment described herein, the closure element 11 is inserted into the cup-shaped element 7 to form an annular chamber 12, which is radially contained between the cylindrical walls 7''' and 11' and axially defined by the radial walls 11'' and 7''.

[0023] The closure element 11 and / or the cup-shaped element 7 further define two radially opposing protrusions 13, which extend axially within the chamber 12 from their respective radial walls 7'', 11''. The protrusions 13 divide the chamber 12 into two preferably equal-sized portions.

[0024] These protrusions 13 are supported by their respective walls 7'', 11'' in a fixed manner, or alternatively, are manufactured integrally with them.

[0025] The pulley 1 also includes a filter assembly 20, which is operatively inserted between the hub 2 and the rim 3 and configured to filter vibrations transmitted between the hub 2 and the rim 3.

[0026] Specifically, in the embodiments described herein, the filter assembly includes at least one resilient component 20, such as two resilient components 20, which are arched and freely circumferentially arranged in corresponding portions of the chamber 12 defined by the protrusion 13.

[0027] Each elastic component 20 includes at least one spring, which in the case described herein is a helical arch spring 21 mounted between the aforementioned protrusions 13.

[0028] The pulley 1 also includes an actuator 22, which is integrally supported by the hub and, in the embodiments described herein, is advantageously manufactured integrally with the hub 2.

[0029] The actuator 22 has two spokes 23 that can move freely circumferentially within the chamber 12, thereby passing between the cup-shaped element 7 and the closing element 11, and is designed to interact with the elastic component 20 through contact, as described below.

[0030] Actuator 22 may contact elastic component 20, possibly with a circumferential interference value, to preload elastic component 20 in seat 12. Alternatively, it may be positioned relative to elastic component 20 within an angular range, i.e., with an angular gap before contacting them.

[0031] The pulley 1 also includes a dust lip 25, which is configured to prevent external contaminants from entering the rotational support 4 between the hub 2 and the rim 3.

[0032] Advantageously, the dust lip is located between the flange 11''' of the closure element 11 (extending relative to the end of the radial annular wall 11'') and the head element 26 integral with the hub 2.

[0033] The damping assembly F also includes a torsional damper 30 rigidly supported by the hub 2, and thus acts in parallel with the pulley 1.

[0034] Advantageously, the torsional damper 30 is a viscous damper.

[0035] Specifically, the torsional damper 30 includes a disc 31 that defines a chamber 32 on the radially outer side of the hub 2, the chamber 32 being designed to accommodate a rotating ring 33 that can slide therein.

[0036] In fact, chamber 32 is designed to contain a type of viscous fluid known in the industry, which is used to resist the movement of rotating ring 33.

[0037] It should be noted in particular that the torsional damper 30 is housed in a space 35, which is radially defined by the hub 2 and the second annular portion 5', axially defined on one side by the connecting wall 9 and the radial annular wall 7' of the cup-shaped element 7, and open on the opposite side.

[0038] In the embodiment shown herein, disc 31 is connected to hub 2 via threaded elements / pins.

[0039] Advantageously, as shown herein, the hub 2 is divided into several parts 2', 2', 2'''. The first part 2' is integrally manufactured with the actuator 22 and supports the support device 4, the second part 2'' supports the disc 31 of the torsional damper 30, and the third part 2''' supports the head element 26.

[0040] The three parts of the hub 2 are advantageously connected to each other by threaded elements / pins, which are preferably also designed to secure the hub 2 to the crankshaft. For this purpose, the three parts 2' define through holes 36 for achieving the aforementioned fixation.

[0041] Advantageously, the connecting wall 9 defines a plurality of openings 40, which are configured to allow airflow into the space 35.

[0042] Specifically, opening 40 passes through connecting wall 9. Specifically, the opening angle of opening 40 is parallel to axis A or may be inclined relative to axis A.

[0043] In particular, the cut of the opening can change its slope along the periphery of the opening 40 to allow air to pass through it. Specifically, the circumferential edges of the opening can have opposite slopes to allow air to enter in any direction of rotation.

[0044] Specifically, the opening 40 is cut into the connecting wall 9, without defining a protrusion along its periphery on both sides of the connecting wall 9. Basically, the periphery of the opening 40 is coplanar with the surface of the connecting wall 9.

[0045] Advantageously, the openings 40 are spaced apart from each other at an angle around axis A, and in particular, are spaced apart evenly from each other. Advantageously, the openings 40 have the same shape.

[0046] Preferably, the opening 40 has a polygonal shape, advantageously a quadrilateral or a trumpet shape, such that the radially inner portion relative to axis A has a smaller angular extension than the radially outer portion. Thus, in the embodiment shown herein, the opening 40 is substantially an isosceles trapezoidal in shape, particularly with rounded vertices.

[0047] Advantageously, in the annular band of the connecting wall 9 affected by the opening 40, at least half of the surface of the annular band is occupied by the opening 40.

[0048] Preferably, the connecting wall 9 further includes a plurality of protrusions 41 extending from the connecting wall 9 and associated with the opening 40. Specifically, the protrusions 41 extend from the side of the connecting wall 9 opposite to the space 35.

[0049] Advantageously, the protrusion 41 is circumferentially inserted between the two openings 40. Preferably, the protrusion 41 is radially more inward relative to the axis A of the opening 40, i.e., the distance from the hub 2 is smaller.

[0050] Specifically, the protrusions 41 are protrusions made by deformation (i.e., by stamping) on ​​the connecting wall 9, so they are integrally manufactured with the connecting wall 9.

[0051] Furthermore, the protrusion 41 is advantageously formed at the junction of the connecting wall 9 and the first radial wall 5'.

[0052] Preferably, the protrusions 41 are truncated pyramidal in shape, i.e., they include an axial wall 41' and a pair of circumferential walls 41'', wherein the axial wall 41' is inclined relative to the plane defined by the vertical axis and the transverse axis (perpendicular to the longitudinal axis A) of the damping assembly F, and the pair of circumferential walls 41'' are also advantageously inclined relative to the plane defined by the longitudinal axis A and the aforementioned vertical axis.

[0053] like Figure 5 and Figure 6 As shown in the best embodiment, the connecting wall 9 includes an inclined portion 9' at the connection with the first annular wall.

[0054] Advantageously, the inclination of the inclined portion 9' is constant about axis A. More advantageously, a protrusion 41 is formed in the region of the inclined portion 9'.

[0055] Specifically, the axial wall 41' of the protrusion 41 is more inclined than the inclined portion 9' of the connecting wall 9, and therefore has a greater radial extension.

[0056] Therefore, in the circumferential direction, the inclined portion 9' is discontinuous due to the presence of the protrusion 41, that is, the inclination is changed due to its radial wall 41'' and axial wall 41'.

[0057] The operation of pulley 1 is as follows.

[0058] In the first operating step, referred to as the "drive mode" and constituting the normal operation of the damping assembly F, the speed of the hub 2 tends to exceed the speed of the rim 3 when the drive shaft drives the accessory. For this purpose, the spokes 23 of the actuator 22 transmit torque to the protrusion 13 via the corresponding inserted elastic components 20.

[0059] This also occurs symmetrically in the “opposite” state, when the speed of rim 3 tends to exceed the speed of hub 2.

[0060] Simultaneously, the damper 30 dampens vibrations occurring on the hub 2 by means of the inertial action of the annular element 33 housed in the chamber 32 relative to the disc 31. During this parallel action, the damper 30 tends to heat up due to friction between the annular element 33 and the fluid contained in the chamber 32.

[0061] During rotation, the opening 40 allows air to pass through the space 35, thereby enabling rapid cooling of the damper 30.

[0062] This airflow effect is enhanced by a specific cross-section of the opening 40. Furthermore, this effect is enhanced by the protrusion 41, which directs air toward the opening 40 by means of the radial wall 41''.

[0063] Therefore, the advantages of the damping component F according to the present invention are obvious.

[0064] The presence of opening 40 allows airflow to the damper 30, enabling it to be cooled during operation.

[0065] Since the openings 40 are merely openings in the connecting wall 9 of the rim 3, i.e., they do not include fins or blades, there is no increase in noise during the rotation of the damping assembly, and its manufacturing cost is reduced compared to existing technology solutions.

[0066] In addition, the specific geometry of the opening allows a large amount of air to enter space 32.

[0067] Specifically, the shapes suggested in this paper make it easier for air to flow into the spaces 35, especially if their edges are angled relative to the longitudinal axis in terms of opening cut.

[0068] The presence of protrusion 41 firstly allows for an increase in the structural strength of the connecting wall 9, a large portion of which is occupied by the opening 40.

[0069] This allows for the simultaneous creation of large airflow through the opening without the need for fins or blades to facilitate air intake, thereby reducing the weight of the rim 3 and, in particular, maintaining sufficient thickness to lower manufacturing costs.

[0070] The effect is further enhanced by the presence of the tilted portion 9', which further increases the strength of the rim 3.

[0071] In detail, the production of wheel rim 3 is particularly cost-effective because the inclined portion 9' and the protrusion 41 can be manufactured by a stamping machine.

[0072] Furthermore, the protrusion 41, due to its truncated pyramidal shape, has an inclined circumferential wall 41'', which helps to direct airflow toward the opening 40 during the rotation of the damping assembly 1.

[0073] In this way, even though no fins or blades are provided for pulley 1, it is still convenient for air to enter opening 40.

[0074] Finally, the aforementioned damping components may be modified or varied without exceeding the scope of protection specified in the appended claims.

[0075] First, pulleys do not necessarily have to be used on the crankshaft of an internal combustion engine, but can be used as one of its accessories.

[0076] Specifically, although a particular structure of filter pulley 1 is described, it is clear that any type of filter pulley can be used to provide torque filtration between hub 2 and rim 3.

[0077] Furthermore, shock absorbers can be manufactured in different types and other geometries.

[0078] Similarly, the geometries of the first and second annular walls 5', 5'' can be different, and the geometries of the opening 40 and the protrusion 41 can also be different.

Claims

1. A damping assembly (F) comprising a filter pulley (1), the filter pulley comprising: A hub (2) configured to be fixed to an axle rotating about a longitudinal axis (A); a rim (3) coaxially and rotatably mounted on the hub (2); at least one filter assembly operatively inserted between the rim (3) and the hub (2); the rim (3) defining a first annular wall (5'') having a profile (6) configured to engage an annular transmission element of a vehicle system; The first annular wall (5'') is supported by a connecting wall (9), which is operatively connected to the filter assembly; The damping assembly (F) includes a torsional damper (30) which is carried by the hub (2) and housed in a space (35) defined by the hub (2), the connecting wall (9) and the first annular wall (5''); The connecting wall (9) defines a plurality of openings (40) configured to allow air to pass through the connecting wall (9) and the space (35).

2. The damping assembly according to claim 1, wherein the peripheral edge of the opening (40) is continuous relative to the connecting wall (9).

3. The damping assembly according to claim 1 or 2, wherein the peripheral edge of the opening (40) does not protrude relative to the connecting wall (9).

4. The damping assembly according to any one of claims 1 to 3, wherein the opening is arranged circumferentially around the longitudinal axis (A).

5. The damping assembly according to any one of claims 1 to 4, wherein the openings (40) are circumferentially spaced apart around the longitudinal axis (A).

6. The damping assembly according to any one of the preceding claims, wherein the edge of the opening (40) is parallel to the longitudinal axis (A).

7. The damping assembly according to any one of claims 1 to 6, wherein the edge of the opening (40) is inclined relative to the longitudinal axis (A).

8. The damping assembly according to claim 6 or 7, wherein the circumferential edges of the opening (40) are inclined in opposite directions relative to the longitudinal axis (A).

9. The damping assembly according to any one of the preceding claims, wherein the opening (40) has a polygonal shape.

10. The damping assembly according to any one of the preceding claims, wherein the opening (40) has a quadrilateral shape.

11. The damping assembly according to any one of the preceding claims, comprising a protrusion (41) circumferentially inserted between two openings (40).

12. The damping assembly according to claim 11, wherein the protrusion (41) has a truncated pyramidal cross-sectional shape.

13. The damping assembly according to claim 11 or 12, wherein the protrusion (41) is radially inward relative to the axis (A) and relative to the opening (40).

14. The damping assembly according to any one of the preceding claims, wherein the filtering assembly includes an elastic component (20) operatively inserted between a first element (22) integral with the hub (2) and a second element (13) integral with the rim (3).

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