WO2013063672A1

WO2013063672A1 - Device for noise removal in automotive shock absorbers

Info

Publication number: WO2013063672A1
Application number: PCT/BR2012/000426
Authority: WO
Inventors: Cesar PIVA
Original assignee: Tenneco Automotive Operating Company Inc.; NARCISO ICHANO, Junior
Priority date: 2011-11-01
Filing date: 2012-08-30
Publication date: 2013-05-10
Also published as: BRMU9102003U2; BRMU9102003Y1; AR088602A4

Abstract

New device model for noise removal in automotive shock absorbers which presents a simple and functional configuration, easy manufacturing and assembly. This device is internally integrated to the vehicle's damper as to progressively decelerate the relative movement of the rod relating to the shock absorbers body, in extension cycles, thus eliminating the mechanical impact of the stop end internal components, and consequently the noise such impact produces.

Description

DEVICE FOR NOISE DISPOSAL OF AUTOMOTIVE SHOCKERS.

This report is a detailed description accompanied by illustrative figures of a model of automotive shock absorber noise elimination device which has a simple and functional configuration, easy to manufacture and assemble. This device is internally integrated with the vehicle's shock absorber to progressively decelerate the relative movement of the rod relative to the shock absorber body during extension cycles, eliminating the mechanical impact of the internal limiting components, and consequently the noise caused by this impact. .

Among the different configurations and designs of existing automotive suspensions, the relative articulation between the suspended and non-suspended mass of the automotive vehicle can use as a travel limiter some components that make up the automotive suspension itself, which limiter is usually offered by the automotive shock absorber. a secondary feature offered by this type of component. The automotive shock absorber, when acting as a limiter of the travel of the automotive suspension and also depending on the damper acting speeds, understood in this specification as the characteristic speed as a function of the relative displacement between the rod and the damper body, as a consequence of the offered excitations. irregularities of the road surface can generate characteristic noises caused by mechanical or hydraulic impact through direct contact between metal or viscoelastic components used shock absorber, generally under operating conditions at maximum rod extension, such noise being undesirable to the work of the automotive suspension.

There are some documents describing various models of shock absorbers with or without noise elimination devices, but none of these models have the device configuration and operation described in this patent. These documents include:

PI 9401784-0 SUSPENSION SHOCK describes a shock absorber of the type comprising: a tubular body (20) internal to a closed tubular housing (0) provided with a central opening (23) passing through an end adjacent to a the ends of the tubular housing (10); and a reciprocating rod (30) axially disposed through the extreme central opening (23) and provided with a stroke limiting element (50, 60), the tubular body (20) having a diametrical reduction (26) to an axial extent. its inner wall adjacent to the central opening (23) which allows, during displacement of the reciprocating rod (60), the contact of the stroke-limiting elastomeric element (50, 60) with the inner wall of the tubular body (20) and at least one of the parts defined by the inner wall of the tubular body (20) and stroke limiting member (50, 60) is provided with axial flow channels (27) for viscous fluid passage during movement of the reciprocating rod (30);

PI 9504936-3, HYDRAULIC SHOCK PISTON PISTON AND PISTON GUIDE, which describes a hydraulic shock absorber piston of the type in which the guide comprises an annular part (3) provided with a center hole (5) and a ring of elastic seal (4). The piston (1) is formed from a single part (7) formed from a revolution body (8) having a convexly curved generatrix. The outer surface of the piston and the inner wall of the center hole (5) of the annular part (3) are provided, at least partially, with respective coatings (6, 9) of uniform thickness, of a material which reduces friction and improves wear resistance, such as polytetrafluoroethylene (ptfe), with a ceramic particle load and a pigment. Said ceramic and pigment particle filler preferably includes mullite and titanium oxide. Said linings (6, 9) of the center hole (5) of the annular part (3) and the outer surface of the piston (1) have a uniform thickness of between 20 and 60 microns;

MU 7603304-0, HYDRAULIC CYLINDER ARRANGEMENT, where the present utility model refers to the new constructive arrangement introduced in hydraulic cylinders with ring that simultaneously serves as a guide and limit stop. The proposed hydraulic cylinder comprises a jacket (1) and telescopic rods (2). In the cylinder the guide rings and stops (3) are mounted near the end of the rods (2) and the retaining rings (4) at the inner ends of the rods (2). Optionally, when the cylinder is single acting, the guide and stop rings (3) are provided with transverse grooves (5);

PI 0212559-5, FRICTION DAMPING SUPPORT, where the invention comprises a friction damping support. The support comprises an inner cylinder (208) which slides into an outer housing (201). A spring 202 propels the inner cylinder away from the outer housing in an axial direction. A first element of wedge (209) cooperatively engages a second wedge member (204). The first wedge member having a frictional engagement with the inner cylinder such that when the inner cylinder is pressed into the outer shell, the first wedge member approaches the second wedge member, causing the first wedge member expand radially thereby increasing the frictional force between the first wedge member and the inner cylinder. A second spring (207) preloads the first wedge member against the second wedge member. A belt tensioner may incorporate the cushioning support for preloading a belt, and may dampen belt swings; and the

PI 0316345-8, TRAFFIC DAMPING SUPPORT, which describes an internal damping component (20) is axially seated in a sternum housing. The outer housing (10) is connectable to a tension arm (11). A wedge-like component (30) connected to an immovable mounting member (40) is axially engaged with an inner portion of the internal damping member. The outer housing is axially movable with respect to the wedge type component. A spring (50) rests on the outer housing and pushes it out of an end cap (60). The end cap comprises a rod 70 which extends axially within the wedge-like member and has an end connected to the internal damping member. The rod transmits a spring loading force from the end cap to the internal damping member such that the internal damping member expands radially against the outer housing in response to the spring loading force, thereby creating a frictional force between the inner damping member and the outer housing that dampens the movement of the outer housing in proportion to the spring force.

In the following reference is made to the Figures accompanying this descriptive report, for a better understanding and illustration of the same where it is seen;

Figure 1 shows a longitudinal section of the automotive shock absorber containing the automotive shock absorber noise suppression device, object of the present patent, with all its configuration and assembly details.

Figure 2 shows a cross-sectional and longitudinal section of one of the component parts of the automotive shock absorber noise suppression device object of the present invention, highlighting its configuration details.

Figure 3 shows a cross-sectional and longitudinal section of the other component parts of the automotive shock absorber noise suppression device object of the present invention, highlighting its configuration details and its kennels.

Figure 4 shows another cross-sectional and longitudinal section of the other component parts of the automotive shock absorber noise suppression device object of the present invention, highlighting its configuration details and its channels.

Figure 5 shows another ejongitu.dinal cross-section of the other part damper noise suppression device components automotive, object of this patent, highlighting its configuration details.

Automotive shock absorbers, regardless of existing configuration, whether hydraulic or not, monotubular, bitubular or even tritubular, have the purpose of generating damping force when subjected to dynamic excitation conditions, characteristics of the suspension articulation given a certain excitation caused by irregularities. on the roadway. These damping forces applied to the suspension aim to bring dynamic stability to the vehicle by controlling the energy dissipation and hence the freedom of articulation of the suspension. Under certain floor excitation conditions, the maximum suspension articulation may be limited by the maximum length of the damper, the limiter of which is provided by internal mechanical components present in this device. The actuation of these internal limiters is given by the mechanical impact between components disposed on the damper rod (usually attached to the vehicle's suspension mass or chassis) and the damper body itself (usually attached to the unsprung mass, or simply wheel suspension assembly). vehicle). Given the constant optimization of motor vehicles and the constant reduction of noise emitted by them, the noise characteristic of the maximum suspension opening becomes undesirable, requiring the reduction or elimination of this type of disturbance.

PI 94017840 discloses a damper having a diametrical reduction in its inner tubular body provided with axial flow channels for viscous fluid passage during rod movement so that this rod has a speed reduction until it reaches course limiter. Promoting a slower deceleration of this rod than conventional to avoid sudden movements in the suspension of vehicles that can be transmitted to passengers or the cargo carried.

This configuration is very difficult and costly to perform as it requires various manufacturing and assembly steps as well as skilled labor and machinery. And due to road conditions, it does not always meet its goals of providing more comfort to passengers or cargo by smoothing suspension movements.

The main purpose of the automotive shock absorber noise elimination device disclosed in this patent report is to provide damping on the shock absorber rod by reducing the damper speed to reach the stroke limiter, and primarily to reduce the noise caused by this movement. of course, performing this task simply and inexpensively, easily manufactured and assembled, in order to make its production feasible.

To achieve this technical effect, the alternative presented in this specification consists of a mechanical-hydraulic device added to the damper, more specifically in the extension chamber, causing the damper to have a progressive increase of damping force in a given region at the end of stroke. damper, with the intent of progressively slowing the relative movement of the rod relative to the damper body during extension cycles, eliminating the mechanical impact of the internal limiting stroke components.

Thus, a non-restrictive preferred embodiment of the present device, object of this patent, is described below. configuration and application may vary as appropriate for each desired model; describing one of the constructive possibilities that lead to the concretization of the object described and the way in which it works.

The automotive damper noise suppression device of the present invention may be used additionally or optionally in any existing automotive shock absorber model, since the increase in damping force at the automotive damper extension stroke is given by the interaction between two cylindrical tubular and concentric components, arranged in the damper pressure chamber, which may be of monotubular, bitubular or even tritubular technology, regardless of the type of fluid used internally, and may be liquid or gaseous. In one of the parts of these shock absorbers, called restrictor tube [1], which may consist of metallic or viscoelastic material, it is concentrically positioned between the damper pressure tube [2] and the upper rod guide [12] by pressing process. or welding, not being restricted to the way this positioning is performed, whose length [3], also not restricted, can be adjusted according to the need of the vehicle, whose part will delimit the region of impact damping for maximum cycles suspension opening. In cases of internal damper space optimization, the restrictor tube may be arranged in the same body as the rod guide as one piece [13]. Similarly, the pressurizing bushing [4] is positioned concentrically to the damper rod [5], supported by a mechanical limiter [6]. In some cases the presence of spring [11] of metallic or viscoelastic composition between the mechanical limiter [6] and the Pressurizing bushing [4] may be required and is not restricted to the technology mentioned herein. The pressurizing bushing may have different geometrical shapes and may vary according to the need of the vehicle suspension, containing axial flow channels [7], of decreasing area or axially constant along the external face of the pressurizing bushing, or even in version. with external linear diameter increase of the pressurizing bushing [8] and, having in the internal area, axial flow channels for fluid return [9], these internal channels can be equidistant or not, with format that may vary according to the need of suspension of the vehicle. The pressurizing bushing is statically and concentrically positioned on the damper rod by means of a locking ring, weld or any mechanical crimping, causing the pressurizing bushing to move equally with the rod's linear displacement in compression and damping extension directions. . Tending to the fullest extent of the damper's extension stroke, the pressurizing bushing is positioned concentric and internally to the restrictor tube, providing increased pressure on the fluid located in the upper chamber [10] of the pressurizing bushing, forcing such fluid to pass through. through the flow channels located in the external area of the pressurizing bushing and, as a consequence, increasing the damping force, causing the damper rod to gradually decelerate the speed relative to the damper body. In the opposite direction of the rod, or simply in the direction of compression, considering that the restrictor bushing is still positioned in the region limited by the restrictor tube, the effect of the spring [11] or simply the inertia makes the pressurizing bushing have a controlled spacing in relation to the mechanical limiter [6], allowing the fluid to flow in the opposite direction through the flow channels in the internal face of the pressurizing bushing, avoiding negative pressures in the chamber between the restrictor tube and the pressurizing bushing, until both stabilize the internal pressure.

Thus, as described above, the automotive shock absorber noise elimination device, object of the present invention, results in a new alternative for noise elimination in these suspension components of a vehicle having a new and unique configuration which gives it great advantages over ratio shock absorbers currently used and currently found in the market. These advantages include the ease of production, assembly and maintenance, as well as the comfort offered by the vehicle to passengers for noise elimination and suspension damping comfort.

Thus, due to the configuration and operating characteristics described above, it can be clearly noted that the Automotive Shock Absorber Noise Elimination Device is a new state-of-the-art device with innovative conditions, unprecedented inventive activity and industrialization, which make it deserve the Utility Model Patent Privilege.

Claims

CLAIM

1 - DEVICE FOR AUTOMOTIVE BUMPER NOISE DEVICE, device for use additionally or optionally in any existing model of automotive monotubular, bitubular or even tritubular automotive shock absorber, regardless of the type of fluid used internally, which may be liquid or gaseous, characterized by: it is essentially a restraining tube [1], which delimits an impact damping region for maximum suspension opening cycles, and may consist of metallic or viscoelastic material and is concentrically positioned between the damper pressure tube [ 2] and the upper rod guide [12] preferably by pressing or welding process, with its length [3], which can be adjusted according to the need of the vehicle; It can be formed from a single piece [13] and arranged in the same body as the rod guide, where the pressurizing bushing [4] is concentrically positioned to the damper rod [5], supported by a mechanical limiter [6]. ] may or may not have a spring [1] of metallic or viscoelastic composition between the mechanical limiter [6] and the pressurizing bushing [4]; where the pressurizing bushing may have different geometrical shapes and may vary according to the need of the vehicle suspension, containing axial flow channels [7], of decreasing or axially constant area along the external face of the pressurizing bushing, or even presenting an external linear diametric increase of the pressurizing bushing [8] and, tending to the internal area, axial flow channels for fluid return [9], these internal channels being equidistant or not, with a format that may vary from according to the need for vehicle suspension; where the pressurizing bushing is statically and concentrically positioned on the damper rod through a locking ring, weld or any type of mechanical crimping, following the linear displacement of the rod in compression and extension damper directions; with the pressurizing bushing positioned concentric and internally to the restrictor tube, allowing fluid to flow through the channels in the positive and negative direction of stem movement.