WO2007033403A1 - Noise attenuation system - Google Patents

Noise attenuation system Download PDF

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Publication number
WO2007033403A1
WO2007033403A1 PCT/AU2006/001266 AU2006001266W WO2007033403A1 WO 2007033403 A1 WO2007033403 A1 WO 2007033403A1 AU 2006001266 W AU2006001266 W AU 2006001266W WO 2007033403 A1 WO2007033403 A1 WO 2007033403A1
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WO
WIPO (PCT)
Prior art keywords
mass
track plate
additional step
energy absorbing
vibrational energy
Prior art date
Application number
PCT/AU2006/001266
Other languages
French (fr)
Inventor
Timothy James Kirkness
Original Assignee
Ghd Pty Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU2005905164A external-priority patent/AU2005905164A0/en
Application filed by Ghd Pty Ltd filed Critical Ghd Pty Ltd
Publication of WO2007033403A1 publication Critical patent/WO2007033403A1/en

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D55/00—Endless track vehicles
    • B62D55/08—Endless track units; Parts thereof
    • B62D55/18—Tracks
    • B62D55/26—Ground engaging parts or elements
    • B62D55/275—Ground engaging parts or elements with street plate, i.e. means to prevent tread from cutting into road surface
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D55/00—Endless track vehicles
    • B62D55/08—Endless track units; Parts thereof
    • B62D55/096—Endless track units; Parts thereof with noise reducing means

Definitions

  • the invention relates generally to a vehicle noise attenuation system, and in particular to a noise attenuation system for reducing noise in tracked vehicles, such as earthmoving vehicles and tanks.
  • tracked vehicles such as earthmoving vehicles and tanks.
  • Track clatter is a combination of a series of vibration frequencies leading to audible noise propagation. To reduce the clatter it is not necessary to eliminate all vibration and consequent noise, but to reduce enough of the vibration to create an acceptable level of audible noise.
  • Known techniques to reduce track clatter include reduction of the transmission of the stimulating vibration to the track plates, mass increase of the track plates, stiffening of the track plates, damping of the track plates, pre-loading of the track plates, modification of track properties by modification of the cross-section of the track, or combinations thereof. It is known to increase the stiffness of track plates by adding thickness to the track plate - either locally (such as by ribbing) or generally (by increasing the track plate thickness or by fixing additional material to the track plate by welding). A potential disadvantage of the local (ribbing) approach is that current manufacturing systems would need to be changed, requiring significant capital cost. A disadvantage of the general (welded additions) approach is fatigue, leading to failure, at the weld joint.
  • the invention provides a noise attenuation system for use in a tracked vehicle, the system comprising: an additional mass for connection to a track plate of the tracked vehicle; and at least one mechanical fastener connecting the mass to the track plate.
  • a first vibrational energy absorbing layer is provided between the mass and the track plate. More preferably, the first vibrational energy absorbing layer is formed from an elastomeric material.
  • the mass is of non-constant cross-section.
  • the mass in an at rest state, includes a concave surface, and in one preferred form, the concave surface is provided on a side of the mass facing the track plate. Alternatively, the concave surface is provided on a side of the mass facing away from the track plate.
  • the mass in another family of embodiments, in an at rest state, includes a convex surface which preferably is provided on a side of the mass facing the track plate. Alternatively, the convex surface is provided on a side of the mass facing away from the track plate.
  • concave or convex surfaces are provided on both sides of the track plate, and in some embodiments, a concave surface is provided on one side and a convex surface on the opposite side.
  • the mass applies a non-uniform stress to the track plate when connected to the track plate by the at least one mechanical fastener.
  • a second vibrational energy absorbing layer is provided between the mass and the fastener. More preferably, the second vibrational energy absorbing layer is formed from an elastomeric material.
  • a third vibrational energy absorbing layer is provided between the track plate and the fastener. More preferably, the third vibrational energy absorbing layer is formed from an elastomeric material.
  • a plurality of the mechanical fasteners are provided for connecting the mass to the track plate.
  • the mass is formed from metal, hi some embodiments, the mass is encased in a vibrational energy absorbing material.
  • the vibrational energy absorbing material is preferably an elastomeric material. In an alternative family of embodiments, the mass is formed from an elastomeric material.
  • the mechanical fastener is chosen from the group comprising: standard bolts, tapped threads using standard bolts or screws, friction grip bolts, rivets, and liuck bolts.
  • the mass is preferably connected to a non-ground engaging side of the track plate. However, in some embodiments the mass is connected to a ground engaging side of the track plate.
  • a plurality of additional masses are provided.
  • the additional masses are all located on the same side of the track plate, and in other embodiments, some of the additional masses are located on one side of the track plate and others on an opposite side of the track plate, hi some embodiments, the additional masses are spaced apart on the same side of the track plate.
  • the invention provides a noise attenuation method for reducing noise generated by tracked vehicles, the method comprising the steps of: providing an additional mass for connection to a track plate of the tracked vehicle; and attaching the mass to the track plate using a mechanical fastener.
  • the method includes the additional step of isolating the mass from the track plate with a first vibrational energy absorbing layer. More preferably, the first vibrational energy absorbing layer is formed from an elastomeric material.
  • the method includes the additional step of providing the mass with a non- constant cross-section.
  • the mass is formed so as to have a concave surface when in an at rest state.
  • the method preferably includes the additional step of connecting the mass to the track plate such that the concave surface faces toward the track plate.
  • the mass is connected to the track plate such that the concave surface faces away from the track plate, m another family of embodiments, the mass is formed so as to have a convex surface when in an at rest state.
  • the method preferably includes the additional step of connecting the mass to the track plate such that the convex surface faces toward the track plate.
  • the mass is connected to the track plate such that the convex surface faces away from the track plate.
  • concave or convex surfaces are provided on both sides of the track plate, and in some embodiments, a concave surface is provided on one side and a convex surface on the opposite side.
  • the mass applies a non-uniform stress to the track plate when connected to the track plate by the at least one mechanical fastener.
  • the method preferably includes the additional step of isolating the mass from the fastener with a second vibrational energy absorbing layer, which is preferably formed from an elastomeric material.
  • the method includes the additional step of isolating the track plate from the fastener with a third vibrational energy absorbing layer, which is preferably formed from an elastomeric material.
  • the method preferably includes the additional step of providing a second said mechanical fastener for connecting the mass to the track plate.
  • the additional mass is formed from metal.
  • the mass is encased in a vibrational energy absorbing material.
  • the vibrational energy absorbing material is an elastomeric material.
  • the additional mass is formed from an elastomeric material.
  • the mechanical fastener is chosen from the group comprising: standard bolts, tapped threads using standard bolts or screws, friction grip bolts, rivets, and huck bolts.
  • the additional mass is connected to a non-ground engaging side of the track plate.
  • the mass is connected to a ground engaging side of the track plate.
  • a plurality of additional masses are provided.
  • the additional masses are all located on the same side of the track plate, and in other embodiments, some of the additional masses are located on one side of the track plate and others on an opposite side of the track plate.
  • FIGS. Ia to Ic show several preferred embodiments of vehicle noise attenuation systems according to the invention.
  • Figures 2a to 2e illustrate several dual mechanical fixing embodiments, showing different plate profiles, with the fasteners omitted for clarity;
  • Figures 3a to 3d illustrate various single mechanical fixing embodiments, showing different plate profiles, with the fasteners omitted for clarity;
  • Figure 4 shows a preferred embodiment of a track cross-section for multiple fixing of additional plates to the track, with the fasteners omitted for clarity;
  • Figure 5 illustrates further embodiments for the fixing of additional plates as well as various embodiments of additional plate cross-sections, with fasteners omitted for clarity.
  • the system 1 comprises an additional mass 3 for connection to a track plate 5 of the tracked vehicle and at least one mechanical fastener 7 connecting the mass 3 to the track plate 5.
  • a plurality of mechanical fasteners 7 are used.
  • only one mechanical fastener 7 is used in the embodiments shown in Figs. 3a to 3d.
  • the additional mass 3 is preferably formed from a metal plate, and in some embodiments (not shown) the additional plate is encased in a vibrational energy absorbing material, such as an elastomeric material.
  • the metal plate is substituted with a constrained elastomeric material. It is preferred to connect the additional mass 3 to a non- ground engaging side 9 of the track plate 5. However, in some embodiments, the mass 3 is connected to a ground engaging side 11 of the track plate 5.
  • an additional mass 3 is connected to both ends 13 and 15 of the track plate 5.
  • additional masses 3 are provided on both a ground engaging 11 and a non-ground engaging 9 side of the track plate 5. The particular position, number, size and shape of the additional masses 3 vary from case to case depending on the damping sought for the track plate 5.
  • a first vibrational energy absorbing layer 17 formed from an elastomeric material is provided between the additional mass 3 and the track plate 5.
  • more than one energy absorbing layer 17 is provided between the additional mass 3 and the track plate 5.
  • the first vibrational energy absorbing layer 17 is not required in some embodiments, and in these cases, the additional mass 3 directly abuts the track plate 5, as shown in Figs. Ia, 2a, 2e, 3a and 4.
  • the additional mass 3 is of non-constant cross-section. It will be appreciated that the different embodiments of the additional mass 3 each produce a different track plate 5 damping. Accordingly, as the damping affects track clatter, one of the cross-sections may reduce the track clatter in a particular track plate 5, whereas a different cross-section may increase the track clatter in the same track plate 5.
  • the additional mass 3 in an at rest state, includes a convex surface 19 adapted for engagement with the track plate 5. Accordingly, when the additional mass 3 is fastened to the track plate 5, the additional mass 3 applies a nonuniform stress to the track plate 5. It will be appreciated that in this embodiment, the compression stress applied on side 9 at the centre of the additional mass 3 is greater than the stress applied at the ends of the additional mass 3.
  • the additional mass 3 in an at rest state, includes a concave surface 21 adapted for engagement with the track plate 5. Accordingly, when the additional mass 3 is fastened to the track plate 5, the additional mass 3 applies a non-uniform stress to the track plate 5. It will be appreciated that in this embodiment, the compression stress applied on side 9 at the ends of the additional mass 3 is greater than the stress applied at the centre of the additional mass 3.
  • a second vibrational energy absorbing layer 23 is provided between the additional mass 3 and the fastener 7.
  • the second vibrational energy absorbing layer 23 is preferably formed from an elastomeric material.
  • a third vibrational energy absorbing layer formed of an elastomeric material is provided between the track plate 5 and the fastener 7.
  • an additional vibrational energy absorbing layer (not shown) is also provided between the masses 3.
  • Various mechanical fasteners 7 can be used to connect the additional mass 3 to the track plate 5.
  • the additional mass 3 can be connected to the track plate 5 using standard bolting (as shown in Figs. Ia to Ic), tapped threads using standard bolts or screws, friction grip bolting, riveting, or huck bolting.
  • the particular fixing strategy chosen depends largely upon the shape of the additional masses 3.
  • the track plate 5, additional masses 3 and vibrational energy absorbing layers 17 are provided with apertures 25 for receiving the fasteners 7.
  • additional fasteners 7 may be required in certain applications.
  • the number of additional masses 3 provided can be varied depending on the particular application. For example, in some embodiments (not shown), more than one additional mass 3 is provided on each side of the track plate 5. Also, in some embodiments (not shown), additional masses 3 are located on both the ground engaging 11 and the non-ground engaging 9 side of the track plate 5. In still further embodiments (not shown), the additional masses 3 have convex or concave surfaces on both sides, or have a convex surface on one side and a concave surface on the opposite side.
  • the illustrated system 1 can be used to "tune" the track plate 5 so as to achieve a desired track plate damping for reducing the severity of track clatter.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Vibration Prevention Devices (AREA)

Abstract

A noise attenuation system (1) for use in a tracked vehicle is disclosed. The system (1) comprises an additional mass (3) for connection to a track plate (5) of the tracked vehicle and at least one mechanical fastener (7) connecting the mass (3) to the track plate (5).

Description

NOISE ATTENUATION SYSTEM
FIELD OF THE INVENTION
The invention relates generally to a vehicle noise attenuation system, and in particular to a noise attenuation system for reducing noise in tracked vehicles, such as earthmoving vehicles and tanks. The invention will be described hereinafter with reference to this application.
BACKGROUND OF THE INVENTION
A typical objective in the design of tracks for tracked dozers and tanks is to reduce track clatter during travelling. Track clatter is a combination of a series of vibration frequencies leading to audible noise propagation. To reduce the clatter it is not necessary to eliminate all vibration and consequent noise, but to reduce enough of the vibration to create an acceptable level of audible noise.
One known approach for attenuating track clatter is to use rubberised track plate surfaces. However, such surfaces experience high wear on rocky ground, which is typical in the working environments of tracked vehicles .
Extensive research has been applied to the selection of highly wear resistant materials for vehicle tracks, which are commonly formed from alloy steel. However, this material tends to clatter excessively while the vehicles are travelling. The clatter is generated from various track plate and track chain interfaces with adjacent components, including contact with drive sprockets, as well as contact with idler wheels and support rollers. Eliminating the cause of the clatter has been pursued for many years with limited success.
As an alternative to eliminating the vibration which causes track clatter, some known systems have attempted to mitigate the effects of the vibration once generated. The present invention is focused in this area.
Known techniques to reduce track clatter include reduction of the transmission of the stimulating vibration to the track plates, mass increase of the track plates, stiffening of the track plates, damping of the track plates, pre-loading of the track plates, modification of track properties by modification of the cross-section of the track, or combinations thereof. It is known to increase the stiffness of track plates by adding thickness to the track plate - either locally (such as by ribbing) or generally (by increasing the track plate thickness or by fixing additional material to the track plate by welding). A potential disadvantage of the local (ribbing) approach is that current manufacturing systems would need to be changed, requiring significant capital cost. A disadvantage of the general (welded additions) approach is fatigue, leading to failure, at the weld joint.
It is also known to cast track plates in such a manner as to preferentially stiffen parts of the track plates. However, manufacturing track plates in this manner is relatively expensive. A more cost effective known track manufacturing technique is to use specially rolled sections, which are cut to length and subsequently machined. However, using this process, it is only possible to create ribbing along a longitudinal axis of the rolled sections. A potential disadvantage of this approach is that no local stiffening is provided transverse to the longitudinal axis of the rolled sections.
OBJECT OF THE INVENTION
It is the object of the present invention to overcome or ameliorate one or more of the disadvantages of the prior art, or at least to provide a useful alternative.
SUMMARY OF THE INVENTION Accordingly, in a first aspect, the invention provides a noise attenuation system for use in a tracked vehicle, the system comprising: an additional mass for connection to a track plate of the tracked vehicle; and at least one mechanical fastener connecting the mass to the track plate.
Preferably, a first vibrational energy absorbing layer is provided between the mass and the track plate. More preferably, the first vibrational energy absorbing layer is formed from an elastomeric material.
Preferably, the mass is of non-constant cross-section. In one family of embodiments, in an at rest state, the mass includes a concave surface, and in one preferred form, the concave surface is provided on a side of the mass facing the track plate. Alternatively, the concave surface is provided on a side of the mass facing away from the track plate. In another family of embodiments, in an at rest state, the mass includes a convex surface which preferably is provided on a side of the mass facing the track plate. Alternatively, the convex surface is provided on a side of the mass facing away from the track plate. In yet further embodiments, concave or convex surfaces are provided on both sides of the track plate, and in some embodiments, a concave surface is provided on one side and a convex surface on the opposite side. Preferably, the mass applies a non-uniform stress to the track plate when connected to the track plate by the at least one mechanical fastener.
Preferably, a second vibrational energy absorbing layer is provided between the mass and the fastener. More preferably, the second vibrational energy absorbing layer is formed from an elastomeric material.
Preferably, a third vibrational energy absorbing layer is provided between the track plate and the fastener. More preferably, the third vibrational energy absorbing layer is formed from an elastomeric material.
Preferably, a plurality of the mechanical fasteners are provided for connecting the mass to the track plate.
In one family of preferred embodiments, the mass is formed from metal, hi some embodiments, the mass is encased in a vibrational energy absorbing material. The vibrational energy absorbing material is preferably an elastomeric material. In an alternative family of embodiments, the mass is formed from an elastomeric material.
Preferably, the mechanical fastener is chosen from the group comprising: standard bolts, tapped threads using standard bolts or screws, friction grip bolts, rivets, and liuck bolts.
The mass is preferably connected to a non-ground engaging side of the track plate. However, in some embodiments the mass is connected to a ground engaging side of the track plate.
hi still further embodiments, a plurality of additional masses are provided. In some embodiments the additional masses are all located on the same side of the track plate, and in other embodiments, some of the additional masses are located on one side of the track plate and others on an opposite side of the track plate, hi some embodiments, the additional masses are spaced apart on the same side of the track plate.
hi a second aspect, the invention provides a noise attenuation method for reducing noise generated by tracked vehicles, the method comprising the steps of: providing an additional mass for connection to a track plate of the tracked vehicle; and attaching the mass to the track plate using a mechanical fastener. Preferably, the method includes the additional step of isolating the mass from the track plate with a first vibrational energy absorbing layer. More preferably, the first vibrational energy absorbing layer is formed from an elastomeric material.
Preferably, the method includes the additional step of providing the mass with a non- constant cross-section. In one family of embodiments, the mass is formed so as to have a concave surface when in an at rest state. In such embodiments, the method preferably includes the additional step of connecting the mass to the track plate such that the concave surface faces toward the track plate. Alternatively, the mass is connected to the track plate such that the concave surface faces away from the track plate, m another family of embodiments, the mass is formed so as to have a convex surface when in an at rest state. In such embodiments, the method preferably includes the additional step of connecting the mass to the track plate such that the convex surface faces toward the track plate. Alternatively, the mass is connected to the track plate such that the convex surface faces away from the track plate. In yet further embodiments, concave or convex surfaces are provided on both sides of the track plate, and in some embodiments, a concave surface is provided on one side and a convex surface on the opposite side.
Preferably, the mass applies a non-uniform stress to the track plate when connected to the track plate by the at least one mechanical fastener.
The method preferably includes the additional step of isolating the mass from the fastener with a second vibrational energy absorbing layer, which is preferably formed from an elastomeric material.
Preferably, the method includes the additional step of isolating the track plate from the fastener with a third vibrational energy absorbing layer, which is preferably formed from an elastomeric material.
The method preferably includes the additional step of providing a second said mechanical fastener for connecting the mass to the track plate.
In one family of preferred embodiments, the additional mass is formed from metal. In some such embodiments, the mass is encased in a vibrational energy absorbing material. Preferably, the vibrational energy absorbing material is an elastomeric material. In an alternative family of embodiments, the additional mass is formed from an elastomeric material. Preferably, the mechanical fastener is chosen from the group comprising: standard bolts, tapped threads using standard bolts or screws, friction grip bolts, rivets, and huck bolts.
In a preferred form, the additional mass is connected to a non-ground engaging side of the track plate. However, in alternative embodiments, the mass is connected to a ground engaging side of the track plate.
In still further embodiments, a plurality of additional masses are provided. In some embodiments the additional masses are all located on the same side of the track plate, and in other embodiments, some of the additional masses are located on one side of the track plate and others on an opposite side of the track plate. BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention will be described hereinafter, by way of examples only, with reference to the accompanying drawings, in which:
Figures Ia to Ic show several preferred embodiments of vehicle noise attenuation systems according to the invention;
Figures 2a to 2e illustrate several dual mechanical fixing embodiments, showing different plate profiles, with the fasteners omitted for clarity;
Figures 3a to 3d illustrate various single mechanical fixing embodiments, showing different plate profiles, with the fasteners omitted for clarity;
Figure 4 shows a preferred embodiment of a track cross-section for multiple fixing of additional plates to the track, with the fasteners omitted for clarity; and
Figure 5 illustrates further embodiments for the fixing of additional plates as well as various embodiments of additional plate cross-sections, with fasteners omitted for clarity.
PREFERRED EMBODIMENTS OF THE INVENTION
Referring to the drawings, there is illustrated a noise attenuation system 1 for use in a tracked vehicle. The system 1 comprises an additional mass 3 for connection to a track plate 5 of the tracked vehicle and at least one mechanical fastener 7 connecting the mass 3 to the track plate 5. In the embodiments shown in Figs. 2a to 2e, a plurality of mechanical fasteners 7 are used. However, only one mechanical fastener 7 is used in the embodiments shown in Figs. 3a to 3d. The additional mass 3 is preferably formed from a metal plate, and in some embodiments (not shown) the additional plate is encased in a vibrational energy absorbing material, such as an elastomeric material. However, in alternative embodiments (not shown), the metal plate is substituted with a constrained elastomeric material. It is preferred to connect the additional mass 3 to a non- ground engaging side 9 of the track plate 5. However, in some embodiments, the mass 3 is connected to a ground engaging side 11 of the track plate 5.
In some embodiments, such as that shown in Fig. 5, an additional mass 3 is connected to both ends 13 and 15 of the track plate 5. In further embodiments (not shown), additional masses 3 are provided on both a ground engaging 11 and a non-ground engaging 9 side of the track plate 5. The particular position, number, size and shape of the additional masses 3 vary from case to case depending on the damping sought for the track plate 5.
In some embodiments, a first vibrational energy absorbing layer 17 formed from an elastomeric material is provided between the additional mass 3 and the track plate 5. In other embodiments (not shown) more than one energy absorbing layer 17 is provided between the additional mass 3 and the track plate 5. However, the first vibrational energy absorbing layer 17 is not required in some embodiments, and in these cases, the additional mass 3 directly abuts the track plate 5, as shown in Figs. Ia, 2a, 2e, 3a and 4.
In some embodiments, such as those shown in Figs. 2c to 2e, 3c and 3d, the additional mass 3 is of non-constant cross-section. It will be appreciated that the different embodiments of the additional mass 3 each produce a different track plate 5 damping. Accordingly, as the damping affects track clatter, one of the cross-sections may reduce the track clatter in a particular track plate 5, whereas a different cross-section may increase the track clatter in the same track plate 5.
In the embodiment shown in Fig. 2e, in an at rest state, the additional mass 3 includes a convex surface 19 adapted for engagement with the track plate 5. Accordingly, when the additional mass 3 is fastened to the track plate 5, the additional mass 3 applies a nonuniform stress to the track plate 5. It will be appreciated that in this embodiment, the compression stress applied on side 9 at the centre of the additional mass 3 is greater than the stress applied at the ends of the additional mass 3. In the embodiment shown in Fig. 3d, in an at rest state, the additional mass 3 includes a concave surface 21 adapted for engagement with the track plate 5. Accordingly, when the additional mass 3 is fastened to the track plate 5, the additional mass 3 applies a non-uniform stress to the track plate 5. It will be appreciated that in this embodiment, the compression stress applied on side 9 at the ends of the additional mass 3 is greater than the stress applied at the centre of the additional mass 3.
In some embodiments, such as that shown in Fig. Ic, a second vibrational energy absorbing layer 23 is provided between the additional mass 3 and the fastener 7. The second vibrational energy absorbing layer 23 is preferably formed from an elastomeric material. In other embodiments (not shown) a third vibrational energy absorbing layer formed of an elastomeric material is provided between the track plate 5 and the fastener 7.
Where multiple additional masses 3 are used, an additional vibrational energy absorbing layer (not shown) is also provided between the masses 3.
Various mechanical fasteners 7 can be used to connect the additional mass 3 to the track plate 5. For example, the additional mass 3 can be connected to the track plate 5 using standard bolting (as shown in Figs. Ia to Ic), tapped threads using standard bolts or screws, friction grip bolting, riveting, or huck bolting. The particular fixing strategy chosen depends largely upon the shape of the additional masses 3. In the illustrated embodiments, the track plate 5, additional masses 3 and vibrational energy absorbing layers 17 are provided with apertures 25 for receiving the fasteners 7.
In the drawings, only embodiments having one or two mechanical fasteners 7 are shown. However, it will be appreciated that additional fasteners 7 may be required in certain applications. Also, the number of additional masses 3 provided can be varied depending on the particular application. For example, in some embodiments (not shown), more than one additional mass 3 is provided on each side of the track plate 5. Also, in some embodiments (not shown), additional masses 3 are located on both the ground engaging 11 and the non-ground engaging 9 side of the track plate 5. In still further embodiments (not shown), the additional masses 3 have convex or concave surfaces on both sides, or have a convex surface on one side and a concave surface on the opposite side.
It will be appreciated that the illustrated embodiments achieve noise attenuation in tracked vehicles by a combination of section modification, mass increase, stiffening and damping.
It will also be appreciated that by varying the position, number, size and/or shape of the additional masses 3, and/or the stress applied by the mechanical fasteners 7, the illustrated system 1 can be used to "tune" the track plate 5 so as to achieve a desired track plate damping for reducing the severity of track clatter.
While the invention has been described with reference to specific embodiments, it will be appreciated that it may also be embodied in other forms.

Claims

CLAIMS:
I . A noise attenuation system for use in a tracked vehicle, the system comprising: an additional mass for connection to a track plate for a tracked vehicle; and at least one mechanical fastener connecting the mass to the track plate.
2. A system according to claim 1, further comprising a first vibrational energy absorbing layer between the mass and the track plate.
3. A system according to claim 2, wherein the first vibrational energy absorbing layer is formed from an elastomeric material.
4. A system according to any one of the preceding claims, wherein the mass is of non-constant cross-section.
5. A system according to claim 4, wherein, in an at rest state, the mass includes a concave surface.
6. A system according to claim 5, wherein the concave surface is provided on a side of the mass facing the track plate.
7. A system according to claim 6, wherein, in an at rest state, the mass includes a convex surface on a side of the mass facing away from the track plate.
8. A system according to claim 5, wherein the concave surface is provided on a side of the mass facing away from the track plate.
9. A system according to claim 8, wherein, in an at rest state, the mass also includes a concave surface on a side of the mass facing the track plate.
10. A system according to claim 8, wherein, in an at rest state, the mass includes a convex surface on a side of the mass facing the track plate.
I I. A system according to claim 4, wherein, in an at rest state, the mass includes a convex surface.
12. A system according to claim 11, wherein the convex surface is provided on a side of the mass facing the track plate.
13. A system according to claim 11, wherein the convex surface is provided on a side of the mass facing away from the track plate.
14. A system according to claim 13, wherein, in an at rest state, the mass also includes a convex surface on a side of the mass facing the track plate.
15. A system according to any one of the preceding claims, wherein the mass applies a non-uniform stress to the track plate when connected to the track plate by the at least one mechanical fastener.
16. A system according to any one of the preceding claims, further comprising a second vibrational energy absorbing layer between the mass and the fastener.
17. A system according to claim 16, wherein the second vibrational energy absorbing layer is formed from an elastomeric material.
18. A system according to any one of the preceding claims, further comprising a third vibrational energy absorbing layer between the track plate and the fastener.
5 19. A system according to claim 18, wherein the third vibrational energy absorbing layer is formed from an elastomeric material.
20. A system according to any one of the preceding claims, comprising two or more said mechanical fasteners connecting the mass to the track plate.
21. A system according to any one of the preceding claims, wherein the mass is o formed from metal.
22. A system according to claim 21, wherein the mass is encased in a vibrational energy absorbing material.
23. A system according to claim 22, wherein the vibrational energy absorbing material encasing the mass is an elastomeric material. s
24. A system according to any one of claims 1 to 20, wherein the mass is formed from an elastomeric material.
25. A system according to any one of the preceding claims, wherein the mechanical fastener is chosen from the group comprising: standard bolts, tapped threads using standard bolts or screws, friction grip bolts, rivets, and huck bolts. 0
26. A system according to any one of the preceding claims, wherein the mass is connected to a non- ground engaging side of the track plate.
27. A system according to any one of claims 1 to 25, wherein the mass is connected to a ground engaging side of the track plate.
28. A system according to any one of the preceding claims, wherein a plurality of 5 additional masses are connected to the track plate by mechanical fasteners.
29. A system according to claim 28, wherein said plurality of additional masses are all located on one side of the track plate.
30. A system according to claim 28, wherein some of said plurality of masses are located on one side of the track plate and others of said masses are located on an opposite o side of the track plate.
31. A noise attenuation method for reducing noise generated by tracked vehicles, the method comprising the steps of: providing an additional mass for connection to a track plate of the tracked vehicle; and 5 attaching the mass to the track plate using a mechanical fastener.
32. A method according to claim 31, including the additional step of isolating the mass from the track plate with a first vibrational energy absorbing layer.
33. A method according to claim 32, including the additional step of forming the first vibrational energy absorbing layer from an elastomeric material.
5 34. A method according to any one of claims 31 to 33, including the additional step of providing the mass with a non-constant cross-section.
35. A method according to claim 34, including the additional step of forming the mass such that it has a concave surface when in an at rest state.
36. A method according to claim 35, including the additional step of connecting the o mass to the track plate such that the concave surface faces toward the track plate.
37. A method according to claim 35, including the additional step of connecting the mass to the track plate such that the concave surface faces away from the track plate.
38. A method according to claim 37, wherein the mass is formed so as to have concave surfaces on both sides when in an at rest state, wherein one of said surfaces faces s the track plate and the other of said surfaces faces away from the track plate.
39. A method according to claim 36, including the additional step of forming the mass such that it has a convex surface on a side of the mass opposite the concave surface.
40. A method according to claim 37, including the additional step of forming the mass such that it has a convex surface on a side of the mass opposite the concave surface. 0
41. A method according to claim 34, including the additional step of forming the mass such that it has a convex surface when in an at rest state.
42. A method according to claim 41, including the additional step of connecting the mass to the track plate such that the convex surface faces toward the track plate.
43. A method according to claim 41, including the additional step of connecting the 5 mass to the track plate such that the convex surface faces away from the track plate.
44. A method according to claim 43 wherein the mass is formed so as to have convex surfaces on both sides when in an at rest state, wherein one of said surfaces faces the track plate and the other of said surfaces faces away from the track plate.
45. A method according to any one of claims 31 to 44, wherein the mass applies a o non-uniform stress to the track plate when connected to the track plate by the at least one mechanical fastener.
46. A method according to any one of claims 31 to 45, including the additional step of isolating the mass from the fastener with a second vibrational energy absorbing layer.
47. A method according to claim 46, including the additional step of forming the 5 second vibrational energy absorbing layer from an elastomeric material.
48. A method according to any one of claims 31 to 47, including the additional step of isolating the track plate from the fastener with a third vibrational energy absorbing layer.
49. A method according to claim 48, including the additional step of forming the third vibrational energy absorbing layer from an elastomeric material.
50. A method according to any one of claims 31 to 49, including the additional step of providing a plurality of mechanical fasteners for connecting the mass to the track plate.
51. A method according to any one of claims 31 to 50, including the additional step of forming the mass from metal.
52. A method according to claim 51, including the additional step of encasing the mass in a vibrational energy absorbing material.
53. A method according to claim 52, wherein the vibrational energy absorbing material encasing the mass is an elastomeric material.
54. A method according to any one of claims 31 to 50, including the additional step of forming the mass from an elastomeric material.
55. A method according to any one of claims 31 to 54, wherein the mechanical fastener is chosen from the group comprising: standard bolts, tapped threads using standard bolts or screws, friction grip bolts, rivets, and huck bolts.
56. A method according to any one of claims 31 to 55, including the additional step of connecting the mass to a non-ground engaging side of the track plate.
57. A method according to any one of claims 31 to 55, including the additional step of connecting the mass to a ground engaging side of the track plate.
58. A method according to any one of claims 31 to 57, wherein a plurality of additional masses are connected to the track plate by mechanical fasteners.
59. A method according to claim 58, wherein said plurality of additional masses are all located on one side of the track plate.
60. A method according to claim 58, wherein some of said plurality of masses are located on one side of the track plate and others of said masses are located on an opposite side of the track plate.
PCT/AU2006/001266 2005-09-19 2006-08-31 Noise attenuation system WO2007033403A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AU2005905164A AU2005905164A0 (en) 2005-09-19 Noise attenuation system
AU2005905164 2005-09-19

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WO2007033403A1 true WO2007033403A1 (en) 2007-03-29

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4123120A (en) * 1976-09-13 1978-10-31 Caterpillar Mitsubishi Ltd. Noise reducing device in undercarriage of track-type vehicle
US4150857A (en) * 1978-01-16 1979-04-24 Caterpillar Tractor Co. Armored cushioning lug for track-type vehicles
JPH08332979A (en) * 1995-04-07 1996-12-17 Ohtsu Tire & Rubber Co Ltd :The Elastic pad for crawler shoe of metallic crawler

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4123120A (en) * 1976-09-13 1978-10-31 Caterpillar Mitsubishi Ltd. Noise reducing device in undercarriage of track-type vehicle
US4150857A (en) * 1978-01-16 1979-04-24 Caterpillar Tractor Co. Armored cushioning lug for track-type vehicles
JPH08332979A (en) * 1995-04-07 1996-12-17 Ohtsu Tire & Rubber Co Ltd :The Elastic pad for crawler shoe of metallic crawler

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
DATABASE WPI Week 199709, Derwent World Patents Index; Class Q22, AN 1997-095190, XP003009580 *

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