Web tension brake anti-squeal improvement

1. A web tension brake assembly which, during operation, always operates with continuous slip so as to reduce resonant vibration of the web tension brake assembly, the web tension brake assembly comprising:

a pair of brake disks mounted on a common brake shaft and extending parallel to and being spaced apart from one another;

at least a first pair of anti-squeal friction pad assemblies being located between the pair of brake disks;

each anti-squeal friction pad assembly, of the first pair of anti-squeal friction pad assemblies, comprising a friction pad, a first back plate adhered to the friction pad, an isolation layer, consisting of silicon rubber, adhered to the first back plate and a second back plate adhered to the silicon rubber isolation layer;

at least a first pneumatically actuated piston being supported by a support plate and located between both the first pair of anti-squeal friction pad assemblies and the pair of brake disks;

the first pneumatically actuated piston being configured to force each anti-squeal friction pad assembly, of the first pair of anti-squeal friction pad assemblies, away from one another into frictional engagement with a respective one of the pair of brake disks;

both of the first and the second back plates having a pair of spaced apart openings for securing the respective anti-squeal friction pad assembly to the support plate by a respective pair of guide studs;

each respective pair of guide studs being fixed to one opposed side of the support plate and extending therefrom for engagement with a respective one of the pair of openings formed in the first and the second back plates of the respective anti-squeal friction pad assembly, and each respective guide stud extending through the respective first back plate, the respective silicon rubber isolation layer and the respective second back plate of the respective anti-squeal friction pad assembly for securing the respective anti-squeal friction pad assembly to the support late while facilitating movement of the respective anti-squeal friction pad assembly, along the respective pair of guide studs, into frictionally engage with the respective brake disk; and

the first pair of anti-squeal friction pad assemblies being configured, during continuous braking, to disrupt an overall symmetry and reduce acoustic resonant vibration and production of noise.

2. The web tension brake assembly of claim 1 , wherein the silicon rubber isolation layer is formulated so as to withstand temperatures that occur due to the continuous slip.

3. The web tension brake assembly of claim 2 , wherein the silicon rubber isolation layer comprises a rubber formulated to withstand temperatures generated by the continuous slip of the web tension brake assembly.

4. The web tension brake assembly of claim 2 , wherein the rubber isolation layer comprises one of a thermoplastic layer, leather or a soft metal layer selected from the group consisting of lead, zinc, aluminum, and alloys thereof.

5. The web tension brake assembly of claim 2 , wherein the rubber isolation layer is configured to change a natural frequency of vibration of the web tension brake assembly.

6. The web tension brake assembly of claim 1 , wherein the web tension brake assembly comprises a second pair of friction pad assemblies located between the pair of brake disks,

at least a second pneumatically actuated piston,

each friction pad assembly, of the second pair of friction pad assemblies, only comprises a friction material adhered to a back plate; and

the second pneumatically actuated piston is configured to force each friction pad assembly, of the second pair of friction pad assemblies, into frictional engagement with a respective one of the pair of brake disks.

7. The web tension brake assembly of claim 6 , wherein the rubber isolation layer acts as an isolator so as to make the first pair of anti-squeal friction pad assemblies behave differently from the second pair of friction pad assemblies.

8. An anti-squeal friction pad assembly set which, during operation, always operates with continuous slip so as to reduce resonant vibration of the anti-squeal friction pad assembly set, said pad assembly set comprising:

a pair of brake disks mounted on a common brake shaft and extending parallel to and being spaced apart from one another;

at least a first pair of anti-squeal friction pad assemblies being located between the pair of brake disks and a second pair of friction pad assemblies being located between the pair of brake disks;

a first pneumatically actuated piston being supported by a support plate and being located between the first pair of anti-squeal friction pad assemblies for biasing the first pair of anti-squeal friction pad assemblies away from one another and into engagement with a respective one of the pair of brake disks;

a second pneumatically actuated piston being located between the second pair of friction pad assemblies for biasing the second pair of friction pad assemblies away from one another and into engagement with a respective one of the pair of brake disks;

each of the first pair of anti-squeal friction pad assemblies comprising an anti-squeal friction pad assembly comprising:

a friction pad;

a front surface of a first back plate adhered to a rear surface of the friction pad; and

an isolation layer, consisting of silicone rubber, disposed between said first back plate and a second back plate, said silicone rubber isolation layer being configured to change a natural frequency of vibration of at least one rotating brake disc during engagement of the first pair of anti-squeal friction pad assemblies via the first pneumatically actuated piston;

both of the first and the second back plates having a pair of spaced apart openings for securing the anti-squeal friction pad assembly to the support plate by a pair of respective guide studs;

each respective pair of guide studs being fixed to one opposed side of the support plate and extending therefrom for engagement with a respective one of the pair of openings formed in the first and the second back plates of the respective anti-squeal friction pad assembly, and each respective guide stud extending through the respective first back plate, the respective silicon rubber isolation layer and the respective second back plate of the respective anti-squeal friction pad assembly for securing the respective anti-squeal friction pad assembly to the support plate while facilitating movement of the respective anti-squeal friction pad assembly, along the respective pair of guide studs, into frictionally engage with the respective brake disk;

each of the second pair of friction pad assemblies comprising a friction material adhered to a back plate; and

the first pair of anti-squeal friction pad assemblies being configured, during continuos braking, to disrupt an overall symmetry and reduce acoustic resonant vibration and production of noise.

9. The pad assembly set of claim 8 , wherein the silicone rubber isolation layer is formulated to withstand temperatures that occur during continuous brake application.

10. A method for reducing squeal in a web tension brake assembly comprising the steps of:

providing a pair of spaced apart brake disks;

supporting at least a first pair of anti-squeal friction pad assemblies on a support plate located between the pair of brake disks;

forming each friction pad assembly, of the first pair of anti-squeal friction pad assemblies, so as to comprise a friction pad, a first back plate adhered to a rear surface of the friction pad, a front surface of a rubber isolation layer adhered to a rear surface of the first back plate and a front surface of a second back plate adhered to a rear surface of the rubber isolation layer;

supporting at least a second pair of pad assemblies on the support plate located between the pair of brake disks;

forming each friction pad assembly, of the second pair of friction pad assemblies, so as to comprise solely a friction material adhered to a back plate;

supporting a first piston on the support plate between the first pair of anti-squeal friction pad assemblies;

both the first and the second back plates having a pair of openings, located on opposite ends of the rubber isolation layer, for securing the respective anti-squeal friction pad assembly to the support plate by a respective pair of guide studs;

supporting a second piston on the support plate between the second pair of friction pad assemblies;

fixing each respective pair of guide stud to one opposed side of the support plate so as to extend therefrom for engagement with a respective one of the pair of openings formed in the first and the second back plates of the respective anti-squeal friction pad assembly;

extending each respective guide stud through the respective first back plate, the respective silicon rubber isolation layer and the respective second back plate of the respective anti-squeal friction pad assembly to secure the respective anti-squeal friction pad assembly to the support plate and facilitate sliding movement of the respective anti-squeal friction pad assembly, along the respective pair of guide studs, into frictionally engage with the respective brake disk;

pneumatically actuating the first piston so as to force the first pair of anti-squeal friction pad assemblies away from one another and frictionally engage each of the first pair of anti-squeal friction pad assemblies with a respective one of the pair of brake disks and simultaneously pneumatically actuating the second piston so as to frictionally engage each of the second pair of friction pad assemblies assembly with a respective one of the pair of brake disks; and

reducing acoustic resonant vibration and noise production by disrupting, via the first pair of anti-squeal friction pad assemblies, an overall symmetry of the web tension brake assembly.