A drive circuit for an electric motor of the type which forms part of a pump in a hydraulic braking circuit of a vehicle comprises an input node, an output node and a voltage and current regulating circuit which connects the nodes and which varies the voltage and current supplied to the output node from the input node in response to a modulation strategy, the input node in use being connected to a battery supply of a vehicle and the output node connected to one side of the electric motor. The voltage and current regulating circuit comprises a switch mode power supply circuit capable of providing at the output node a voltage that is either above or below the battery supply voltage at the input node.

An abnormality diagnostic device and an abnormality diagnostic method for a booster according to the present invention: determine that a negative pressure sensor operates normally, when an output of the negative pressure sensor changes in response to a decrease in intake pressure; determine that a negative pressure pump operates normally, when the pressure in a negative pressure chamber is decreased by operating the negative pressure pump, and the pressure decrease is determined by the negative pressure sensor determined to be normal; determine that the negative pressure pump is abnormal when the pressure decrease is not determined by the negative pressure sensor; and determine that a negative pressure leakage has occurred, when the pressure in the negative pressure chamber, which has been decreased by the negative pressure pump, is not maintained.

An abnormality diagnostic device and an abnormality diagnostic method for a booster according to the present invention: determine that a negative pressure sensor operates normally, when an output of the negative pressure sensor changes in response to a decrease in intake pressure; determine that a negative pressure pump operates normally, when the pressure in a negative pressure chamber is decreased by operating the negative pressure pump, and the pressure decrease is determined by the negative pressure sensor determined to be normal; determine that the negative pressure pump is abnormal when the pressure decrease is not determined by the negative pressure sensor; and determine that a negative pressure leakage has occurred, when the pressure in the negative pressure chamber, which has been decreased by the negative pressure pump, is not maintained.

A Venturi device for producing vacuum from fluids in an engine system has a body defining a Venturi gap separating apart an outlet end of a converging motive section and an inlet end of a diverging discharge section by a lineal distance, and a suction port in fluid communication with the Venturi gap. The converging motive section and the diverging discharge section both gradually, continuously taper toward the Venturi gap, the converging motive section defines a circular-shaped motive inlet and an elliptical- or polygonal-shaped motive outlet, the diverging discharge section defines an elliptical- or polygonal-shaped discharge inlet, and an inner passageway of the converging motive section transitions as a hyperbolic function from the motive inlet to the elliptical- or polygonal-shaped motive outlet.

A Venturi device for producing vacuum from fluids in an engine system has a body defining a Venturi gap separating apart an outlet end of a converging motive section and an inlet end of a diverging discharge section by a lineal distance, and a suction port in fluid communication with the Venturi gap. The converging motive section and the diverging discharge section both gradually, continuously taper toward the Venturi gap, the converging motive section defines a circular-shaped motive inlet and an elliptical- or polygonal-shaped motive outlet, the diverging discharge section defines an elliptical- or polygonal-shaped discharge inlet, and an inner passageway of the converging motive section transitions as a hyperbolic function from the motive inlet to the elliptical- or polygonal-shaped motive outlet.

A circuit has a fluid line matrix and brake components connected to the fluid line matrix. Changes in the brake designs or brake functions can be carried out easily in that at least one interface is provided for connecting a distributor block. The interface is designed such that a configuration of the fluid line matrix can be formed by connecting or exchanging the distributor block. There is also described a distributor block which is suitable for forming a configuration of the fluid line matrix of the circuit by connecting to the at least one interface of the circuit.

A vacuum generator/amplifier system for gas applications and a brake booster generation method uses a vacuum amplifier system including a multi-lumen defining member comprising a modified venturi geometry having a converging section leading to a throat (lumen segment of minimum ID diameter), followed by a straight section culminating in to a diverging section and a port for output vacuum which is located after the throat at the beginning of the straight section. The converging section has a sinusoidal shape leading to the point of convergence, also called the throat, with a minimum internal lumen diameter D, and generates an amplified vacuum at the output with a gain ratio of four to one, with substantially reduced parasitic losses, even at low flows.

An electric component assembly includes a housing with which an electric component is fitted together, and the electric component and the housing are fixed to one side of a base body. The electric component includes a connecting terminal configured to be press-fitted in a through-hole of the control board of the housing, and a direction in which the connecting terminal is inserted into the through-hole is same as a fitting direction relative to the housing. There are provided a rib protruding from one of the electric component and the housing, and a groove portion recessed from another one of the electric component and the housing and into which the rib is press-fitted. Movement of the electric component in a direction intersecting the fitting direction and rotation of the electric component around an axis parallel to the fitting direction are restrained by the rib press-fitted into the groove portion.

A simple, compact, and economical motor/pump unit for supplying vacuum to a pneumatic brake booster of a motor-vehicle brake system, wherein the motor/pump unit is designed as a diaphragm pump having a single elastomeric diaphragm, which is moved by an electrically operated motor unit by an eccentric drive, and has a pump housing and a working-space cover and the diaphragm is clamped between the pump housing and the working-space cover at the radial outer edge of the diaphragm in a sealing manner and the working-space cover is designed as a multi-part working-space cover having an upper cover, a lower cover, and an inlet valve and an outlet valve, which are arranged between the upper cover and the lower cover and control the air circulation through the working space.

A simple, compact, and economical motor/pump unit for supplying vacuum to a pneumatic brake booster of a motor-vehicle brake system, wherein the motor/pump unit is designed as a diaphragm pump having a single elastomeric diaphragm, which is moved by an electrically operated motor unit by an eccentric drive, and has a pump housing and a working-space cover and the diaphragm is clamped between the pump housing and the working-space cover at the radial outer edge of the diaphragm in a sealing manner and the working-space cover is designed as a multi-part working-space cover having an upper cover, a lower cover, and an inlet valve and an outlet valve, which are arranged between the upper cover and the lower cover and control the air circulation through the working space.