Brake assembly

1 . A brake assembly comprising:

a caliper that has a guide bore;

a brake carrier arranged to receive a brake pad;

a guide pin comprising a guide sleeve secured to the brake carrier, the guide pin defining an axial direction and being received within the guide bore of the caliper, wherein the caliper is slidable relative to the brake carrier along the guide sleeve; and

a lock arrangement at least partially interposed between the guide bore and the guide sleeve, the lock arrangement comprising a friction element, wherein the lock arrangement is operable to selectively apply a force to the friction element to increase friction between the guide sleeve and the guide bore and inhibit relative sliding between the caliper and the brake carrier in the axial direction when a braking operation has ended and the brake pad is spaced apart from a rotor,

wherein the friction element is configured to be deformed by the force applied by the lock arrangement, wherein the friction element is configured to be compressed in the axial direction and expanded in a radial direction by the force applied by the lock arrangement.

2 . The brake assembly of claim 1 wherein the friction element has a cross-sectional area, and the cross-sectional area remains constant as the friction element is deformed.

3 . The brake assembly of claim 1 wherein the lock arrangement comprises a retaining cage that houses the friction element, wherein the retaining cage further comprises an axially fixed element and an axially movable element, wherein the friction element is located between the axially fixed element and the axially movable element, and wherein when the lock arrangement is operated, the axially movable element is moved towards the axially fixed element to apply the force to the friction element.

4 . The brake assembly of claim 3 wherein the retaining cage, the axially movable element, the axially fixed element, and the friction element are all annular.

5 . The brake assembly of claim 4 wherein the axially movable element has a radially inner thread that engages a radially outer thread of the guide sleeve, wherein rotation of the axially movable element results in movement of the axially movable element relative to the guide sleeve.

6 . The brake assembly of claim 3 wherein the axially fixed element is axially fixed relative to the guide sleeve.

7 . The brake assembly of claim 3 wherein the retaining cage has a low-friction radially outer surface.

8 . The brake assembly claim 3 wherein the retaining cage comprises one or more cut-outs to enable the friction element to expand radially outwardly through the one or more cut-outs.

9 . The brake assembly of claim 8 wherein the retaining cage comprises at least two circumferentially distributed cut-outs.

10 . The brake assembly of claim 3 wherein a gap is defined between the axially fixed element and the axially movable element, wherein the gap locates the frictional element, and the axially fixed element and the axially movable element have opposing angled end faces and the gap tapers outwardly in a radially outward direction.

11 . The brake assembly of claim 1 wherein the friction element is an annular resilient element.

12 . The brake assembly of claim 11 wherein the annular resilient element is an o-ring.

13 . The brake assembly of claim 1 wherein the friction element is configured to be moved in a radial direction by the force applied by the lock arrangement.

14 . The brake assembly of claim 13 wherein the lock arrangement comprises a retaining cage that houses the friction element, wherein the retaining cage further comprises an axially fixed element and an axially movable element, wherein the friction element is located between the axially fixed element and the axially movable element, and wherein when the lock arrangement is operated, the axially movable element is moved towards the axially fixed element to apply the force to the friction element.

15 . The brake assembly of claim 14 wherein the retaining cage comprises one or more cut-outs to retain the friction element and allow the friction element to move radially outwardly through the one or more cut-outs.

16 . The brake assembly of claim 14 wherein the lock arrangement comprises a plurality of friction elements distributed circumferentially, and the retaining cage comprises a plurality of circumferentially distributed cut-outs that correspond to the plurality of friction elements, and opposing angled end faces of the axially fixed element and the axially movable element direct the friction elements through the cut-outs and into contact with an inner surface of the guide bore when the lock arrangement is operated.

17 . The brake assembly of claim 16 wherein each friction element is a ball bearing.

18 . A brake assembly comprising:

a caliper that has a guide bore;

a brake carrier arranged to receive a brake pad;

a guide pin comprising a guide sleeve secured to the brake carrier, the guide pin defining an axial direction and being received within the guide bore of the caliper, wherein the caliper is slidable relative to the brake carrier along the guide sleeve; and

a lock arrangement at least partially interposed between the guide bore and the guide sleeve, the lock arrangement comprising a friction element, wherein the lock arrangement comprises a retaining cage disposed adjacent to the friction element, wherein the retaining cage further comprises an axially fixed element and an axially movable element, wherein the friction element is located between the axially fixed element and the axially movable element;

wherein the lock arrangement is operable to selectively apply a force to the friction element to increase friction between the guide sleeve and the guide bore and inhibit relative sliding between the caliper and the brake carrier, wherein when the lock arrangement is operated, the axially movable element is moved towards the axially fixed element to apply the force to the friction element; and

wherein the friction element is configured to be deformed by the force applied by the lock arrangement, wherein the friction element is configured to be compressed in the axial direction and expanded in a radial direction by the force applied by the lock arrangement.

19 . A brake assembly comprising:

a caliper that has a guide bore;

a brake carrier arranged to receive a brake pad;

a guide pin comprising a guide sleeve secured to the brake carrier, the guide pin defining an axial direction and being received within the guide bore of the caliper, wherein the caliper is slidable relative to the brake carrier along the guide sleeve; and

a lock arrangement at least partially interposed between the guide bore and the guide sleeve, the lock arrangement comprising a friction element;

wherein the lock arrangement is operable to selectively apply a force to the friction element to increase friction between the guide sleeve and the guide bore and inhibit relative sliding between the caliper and the brake carrier in the axial direction when a braking operation has ended and the brake pad is spaced apart from a rotor; and

wherein the friction element is configured to be moved in a radial direction by the force applied by the lock arrangement.