Pump driven by an electromotor and method for producing a pump of this type

Abstract

The invention relates to a pump (10), having a pump head (12), which has a pump chamber (11), and having an electric motor (14), which drives the pump head (12) and has a stator (40) and a rotor (38), the rotor (38) being connected to the pump head (12) and being disposed in a rotor chamber (82) open toward the pump chamber (11). It is proposed that the stator (40) is disposed radially around the rotor chamber (82), and the rotor chamber (82) is sealed off from the pump chamber (11) by a sealing wall (51) belonging to the stator (40) and by at least one wall (64) of the pump housing (18).

Description

PRIOR ART[0001] The invention is based on a motor pump having a pump head and an electric motor that drives the pump head, as generically defined by the preamble to claim 1, and to a method for producing such a pump, as generically defined by the preamble to claim 20.[0002] Such motor pumps serve to transport or increase the pressure of a fluid and have long been used, for instance as water pumps in heating circuits.[0003] From European Patent EP-0 778 649 B1, a pump-motor unit is known, which acts as a coolant pump of a motor vehicle internal combustion engine. The pump-motor unit described in EP-0 778 649 B1 is a centrifugal pump, which is driven by an electronically commutated direct-current motor. The centrifugal pump and the direct-current motor are connected to one another via a radiator. Fastened between the pump housing and the radiator is a split pot, made of a suitable material, which separates the rotor of the electric motor from the stator. A seal placed between the pump...

AI Technical Summary

Benefits of technology

The invention is a motor pump with a simplified design that eliminates the need for a separate split tube to seal off the rotor chamber from the stator chamber. The pump includes a pump head and an electric motor driving the pump head, with an electronic switch mechanism for controlling the motor. The pump head and motor are housed in a common housing, which serves as a radiator for the electronics. The sealing wall of the split pot is directly attached to the stator, eliminating the need for a separate component. The use of a plastic casing for the stator further offers the advantage of simplified and secure fixation of the stator pole teeth. The technical effects of the invention include improved cooling of the electronics, simplified assembly, and reduced cost.

Problems solved by technology

One disadvantage of the pump-motor unit described in EP-0 778 649 B1 and of all comparable motor pumps is the existing air gap between the stator and the rotor of the electric motor, which adversely affects the efficiency of a split tube motor of this kind.

Reducing the air gap by lessening the thickness of the material of the split pot has the risk of mechanical instabilities of the split pot.

This can cause premature failure of the pump.

Cooling the power electronics of the control motor by means of an additional passive radiator, as proposed in EP-0 778 649 B1-besides requiring one additional split pot increases the complexity of such a pump.

Once again, the complex assembly and sealing of the additional split pot is a disadvantage.

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