Rotating pump

Abstract

A rotating pump includes an outer and an inner rotor disposed in a casing with a gap between the casing and the outer rotor. The rotating pump also includes a first and a second sealing member in the casing to define a low-pressure region and a high-pressure region within the gap. Each of the first and second sealing members is made up of a seal functioning portion and an elastically pressing portion. The seal functioning portion includes a resinous member and a deformation-suppressing member. The resinous member contacts the outer rotor and a low-pressure side inner surface of the casing to establish a difference in pressure between the low-pressure region and the high-pressure region. The deformation-suppressing member works to stop the resinous member from deforming undesirably. This minimizes the risk of breakage of the resinous member and enables the rotating pump to discharge the fluid at an increased pressure.

Description

[0001]The present application claims the benefit of priority of Japanese Patent Application No. 2014-22442 filed on Feb. 7, 2014, the disclosure of which is incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1.Technical Field of the Invention[0003]This disclosure relates generally to a rotating pump designed to suck and then discharge fluid, and more particularly to such a rotating pump which is useful for a brake system working to suck and discharge brake fluid to regulate the pressure thereof for controlling the braking force.[0004]2. Background Art[0005]Japanese Patent First Publication No. 2002-295376 teaches use of an internal gear pump, such as a trochoid pump, as a rotating pump for an automotive brake system. This type of rotating pump is made up of an inner rotor, an outer rotor, and a casing. The inner rotor is equipped with outer teeth formed on an outer periphery thereof. The outer rotor is equipped with inner teeth formed on an inner periphery thereof. Th...

AI Technical Summary

Benefits of technology

[0012]The resinous member is pressed by the high pressure of the fluid, but stopped by the deformation-suppressing member of the seal functioning portion from being deformed into the low-pressure region of the gap, thereby minimizing the risk of breakage of the resinous member to ensure the stability of sealing the gap. This enables the rotating pump to discharge the fluid at an increased pressure.

Problems solved by technology

The above described conventional sealing mechanisms, however, need to have a large clearance between the casing and the outer rotor for meeting a pressure requirement because of design limitations in terms of production tolerance of the pump.

It is, therefore, impossible for the pump to have the required endurance against the discharge of the brake fluid at high pressure.

For instance, the resin member may deform into the clearance between the casing and the outer rotor, thereby resulting in breakage of the resin member, which leads to a lack of sealing ability of the sealing mechanism.

It is, thus, difficult to ensure the durability of the sealing mechanisms and achieve the discharging of the brake fluid at high pressure.

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