BRAKE SHOE WITH A BRAKE LINING HAVING SPATIALLY VARYING THERMAL MATERIAL PROPERTIES

Abstract

The invention relates to a brake shoe for a drum brake system, the brake shoe having a length configured to extend in a circumferential direction of a brake drum of the drum brake system, and a width configured to extend in an axial direction of the brake drum, wherein the brake shoe has spatially varying thermal properties along its length, in particular a change in heat capacity and/or a change in thermal expansion coefficient and/or a change in thermal conductivity. The invention also relates to a drum brake system having a brake shoe of the above-mentioned type.

Description

Claims

1. A brake shoe for a drum brake system, the brake shoe having a length configured to extend in a circumferential direction of a brake drum of the drum brake system, and a width configured to extend in an axial direction of the brake drum, wherein the brake shoe has spatially varying thermal properties along its length, in particular a change in heat capacity and/or a change in thermal expansion coefficient and/or a change in thermal conductivity.

2. The brake shoe according to claim 1, having a leading side and a trailing side, wherein the heat capacity and/or the thermal conductivity and/or the thermal expansion coefficient increases from the leading side of the brake shoe to the trailing side.

3. The brake shoe according to claim 1, comprising at least two segments, with different thermal properties from one another, in particular with different heat capacity and/or different thermal expansion coefficient and/or different thermal conductivity from one another.

4. The brake shoe according to claim 3, wherein the at least two segments are provided in a brake lining and/or in a lining holder of the at least one brake shoe.

5. The brake shoe according to claim 3, comprise a first segment being a leading segment, and a second segment adjacent to the first segment, wherein the heat capacity and/or the thermal expansion coefficient and/or the thermal conductivity in the first segment is at least 5 % less than the heat capacity and/or the thermal expansion coefficient and/or the thermal conductivity in the second segment.

6. The brake shoe according to claim 1, wherein the at least three segments are provided in a brake lining and/or in a lining holder of the at least one brake shoe.

7. The brake shoe according to claim 6, wherein the at least three segments are provided in a brake lining and/or in a lining holder of the at least one brake shoe.

8. The brake shoe according to claim 6, comprise a first segment being a leading segment, and a second segment adjacent to the first segment, wherein the heat capacity and/or the thermal expansion coefficient and/or the thermal conductivity in the first segment is at least 5 % less than the heat capacity and/or the thermal expansion coefficient and/or the thermal conductivity in the second segment.

9. The brake shoe according to claim 8, comprising a third segment adjacent to the second segment, wherein the heat capacity and/or the thermal expansion coefficient and/or the thermal conductivity in the third segment is at least 5 % more than the heat capacity and/or the thermal expansion coefficient and/or the thermal conductivity in the second segment.

10. The brake shoe according to claim 1, wherein the spatially varying thermal properties are provided in a brake lining of the brake shoe, the brake lining having: a heat capacity that is in a range from 5 J/(Kg*K) to 20 J/(Kg*K), the heat capacity of the brake lining varying by at least 10 % along the length of the brake shoe, and/ora volumetric thermal expansion coefficient that is in a range from 100*E-061/K to 300*E-061/K, the volumetric thermal expansion coefficient of the brake lining varying by at least 10 % along the length of the brake shoe, and/ora thermal conductivity that is in a range from 0.1 W/(m*K) to 0.8 W/(m*K), the thermal conductivity of the brake lining varying by at least 10 % along the length of the brake shoe.

11. The brake shoe according to claim 1, wherein the spatially varying thermal properties are provided in a lining holder of the brake shoe, the lining holder comprising steel and/or cast iron.

12. The brake shoe according to claim 1, wherein the spatially varying thermal properties are provided in a lining holder of the brake shoe, the lining holder having: a heat capacity that is in a range from 280 J/(Kg*K) to 420 J/(Kg*K), the heat capacity of the lining holder varying by at least 10 % along the length of the brake shoe, and/ora volumetric thermal expansion coefficient that is in a range from 24*E-061/K to 36*E-061/K, the volumetric thermal expansion coefficient of the lining holder varying by at least 10 %along the length of the brake shoe, and/ora thermal conductivity that is in a range from 8 W/(m*K) to 18 W/(m*K), the thermal conductivity of the lining holder varying by at least 10 % along the length of the brake shoe.

13. The brake shoe according to claim 1, wherein the brake shoe has a spatially varying friction coefficient along its length.

14. A drum brake system for a vehicle, having a brake drum, a leading brake shoe and a trailing brake shoe, wherein at least one of the leading brake shoe and the trailing brake shoe, is a brake shoe according to claim 1, in particular both the leading brake shoe and the trailing brake shoe are brake shoes according to any of the preceding claims .

15. The drum brake system according to claim 14, wherein the change in heat capacity and/or the change in thermal expansion coefficient and/or the change in thermal conductivity of the leading brake shoe is greater than the change in heat capacity and/or the change in thermal expansion coefficient and/or the change in thermal conductivity of the trailing brake shoe.