Abstract: A vehicle switch means includes an electric switch operatively closed or opened as driven by a central spindle controlled by a vacuum controller communicated with an inlet manifold of a car engine, whereby when the car is subject to a heavy load, the weak vacuum suction force in the inlet manifold will not suck a diaphragm in the vacuum controller and the spindle will be resiliently restored outwardly to switch off the electric switch to stop the running of compressor of a car air conditioner, thereby reducing the car engine load and being helpful for climbing a steep surface.

Abstract: A vehicle brake system includes: a brake master cylinder having a cylinder body and a master cylinder piston slidably received in the cylinder body, a plurality of wheel cylinders connected to the cylinder body of the master cylinder, an oil reservoir filled with brake hydraulic oil formed on a rear portion of the cylinder body and a pressure-reducing cylinder mounted on the brake master cylinder. Whenever braking a car provided with such a brake system, a brake pedal may be trodden to actuate the master cylinder piston to compress the brake hydraulic oil to brake the car wheels. However, an oil flow will be by-passed from an outlet pipe of the master cylinder to move a depressing piston restored in the pressure-reducing cylinder to by-pass an oil flow to return into the oil reservoir of the master cylinder for reducing the hydraulic oil pressure in the brake system for preventing a sudden locking a sudden locking of the car wheels in order for a safer emergency brake operation.

Abstract: A vacuum controller serving as a fuel saver includes a suction chamber communicated with a vacuum port of an engine carburetor and a plunger valve reciprocatively moved as actuated by the suction pressure in the suction chamber to control the air flow through a by-pass secondary air tube from an air filter towards a fuel inlet manifold for the complete combustion of fuel and for saving energy purpose.