Displacement pump with variable volume flow

Abstract

A displacement pump with variable volume flow having a casing; a chamber with an inlet opening on a low pressure side and an outlet opening on a high pressure side for a fluid; an internal rotor capable of rotation about a rotational axis (D_I); a ring having a central ring axis (D_A) surrounding the internal rotor and forming together with the ring, at least one delivery cell in which fluid is delivered from a low pressure side to a high pressure side of the pump; and an adjusting device which, during an adjusting movement, rolls off on the casing without slipping is provided. The internal rotor is fixed to the adjusting device and rotatble about the rotational axis (D_I), and the position of the rotational axis (D_I) relative to the central ring axis (D_A) of the ring is adjusted by the adjusting movement of the adjusting device.

Description

FIELD OF THE INVENTION [0001] The invention relates to displacement pumps, in particular internal-axle gear pumps, but also wing cell pumps or for example also pendulum slider pumps, whose volume flow can be varied according to requirement, i.e. can be adjusted. The pumps in accordance with the invention are preferably used as lubricant oil pumps for internal combustion engines, wherein the internal combustion engine itself preferably drives the lubricant oil pump in question. The internal combustion engine can in particular be a drive motor, preferably a piston motor, of a vehicle. The specific volume flow, i.e. the volume flow delivered per revolution of a delivery wheel of the pump, can preferably be adjusted continuously. The displacement pumps can also be advantageously used as supply pumps for automatic transmissions in vehicles and when used in this way are also preferably driven by the drive motor of the vehicle in question. Although the displacement pump of the invention, w...

AI Technical Summary

Benefits of technology

[0010] By omitting the variable ring around the external rotor and by increasing the speed of the internal rotor in proportion to the numbers of teeth from the external rotor to the internal rotor as compared to the drive speed, the design space of the variable pump required is reduced superproportionally, for the same specific delivery amount.

[0011] Such a variable pump in accordance with the invention is thus also suitable for small-volume internal combustion engines, in which particular value is placed on reducing the hydrostatic losses and the circulated amount of oil at high speeds.

[0012] The compactness of a variable displacement pump in accordance with the invention can h

Problems solved by technology

However, it has proven in practice that the design space available in increasingly compact reciprocating piston motors is becoming smaller and smaller.

Since these pumps are preferably arranged in the oil sump of the crankcases and since a mass-balance shaft often also has to be additionally accommodated in this region, together with other influencing factors such as conductor frame fortification of the crankcase and a highly pitched oil pan for ground clearance and the a

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