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UK: Bosch readies automatic parking brake for 2005 production

By just-auto.com editorial team | 10 September 2003

Bosch is preparing a new design of handbrake, the Automated Parking Brake (APB), for volume production. APB will make it possible for the first time for vehicle manufacturers to dispense entirely with either cables or electric motors that make up existing systems. Instead the driver will operate the parking brake simply by pressing a button or switch.

Various designs of automated parking brake have been on the market for some time already. These work either by having an electric motor do the work of pulling the brake cable, or by having electric motors on the callipers to push the brake pads against the brake disc.

Bosch's APB design is much simpler by comparison, and hence more durable and more cost efficient. It uses the same electronic architecture as ESP so, aside from fitting ESP, all the manufacturer will have to do is fit a couple of modified Bosch brake callipers.

When the driver presses the switch to operate the parking brake, the ESP unit automatically generates pressure and pushes the brake pads against the brake disc. An electro-magnetic valve built into the calliper controls a secondary hydraulic circuit, which locks the disc brake. When the driver presses the switch a second time, the ESP generates pressure again briefly - and the same mechanism releases the brake.

Dispensing with the handbrake lever has another great advantage. It frees up extra space for the car interior designers to make use of. Bosch expects volume production of its APB to begin in 2005.