Control valves regulate pressure within the braking system, and there are three types - the metering valve, the proportioning valve. Floating calipers are also attached to brackets and sit sandwiching the rotor, but they only have a piston on one side. Both pistons are located on the inboard side of the brake disc. Floating calipers come with either one or two pistons. They don’t mount rigidly and instead, slide freely on lubricated pins and bushings. and there are two types used - the stoplight switch and the braking warning light switch. Floating calipers are compact, lightweight, and not as powerful. There are several types of switches and control valves used in hydraulic brake systems. As pressure is increased, the pistons force the brake pads against the rotor evenly, therefore maintaining an equal amount of pressure on both sides of the rotor. If the lining should wear unevenly on one side of the caliper, the piston would take up the excess clearance simply by moving further out of the bore.Īs the brakes are applied, fluid pressure enters the caliper on one side and is routed to the other through an internal passage or by an external tube connected to the opposite half of the caliper. It is a variation of the floating caliper, using a single piston. A set of slider pins or bolts allow the caliper to slide back and forth as the brakes are applied and released. sliding calipers), on the other hand, mount to an adapter plate, which is bolted to the steering knuckle. 7-18) is mounted in a slot in the caliper adapter. Fixed calipers mount directly to the steering knuckle and do not move back and forth. The pistons accomplish the centering action of the fixed caliper, as they move in their bores. The sliding caliper type disc brake (fig.

In this design, the caliper usually is made in two pieces and has two or more pistons in use. 7-19) is rigidly mounted to the spindle or splash shield. The machined surfaces of the caliper housing slide on the mated surfaces of the caliper adapter when the brakes are applied.įIXED CALIPER. Each has two angular machined surfaces: this is where the sliding contacts come into play. This design has two major sections - the sliding caliper and the caliper adapter (anchor plate). It is a variation of the floating caliper, using a single piston and operating on the same principle, whereby the piston applies pressure to one brake pad and the movable caliper applies pressure to the other. 7-18) is mounted in a slot in the caliper adapter. The sliding caliper type disc brake (fig. This action develops additional braking force. As pressure is built up behind the piston, it forces the brake pads to tighten against the rotor. In this paper, a new model to study the onset of the dynamic instability in a floating caliper disk brake is presented. Additional pressure then forces the caliper assembly to move in the opposite direction of the piston, thereby forcing the brake pad on the opposite side to contact the rotor.