DE202012009130U1 - Piston pump for a high-pressure cleaner - Google Patents

Abstract

Piston pump for a high-pressure cleaning device with an oil-filled pump housing, in which a plurality of pistons are arranged, which are acted upon by a swash plate, which is driven by a motor shaft, characterized in that the motor shaft (2a) in the region of the swash plate (3) at least one oil passage ( 2c) to the swash plate support bearing (3a) towards.

Description

The invention relates to a piston pump for a high-pressure cleaning device with the preamble features of claim 1.

Such a piston pump is z. B. from the U.S. Patent 4,636,146 known as a precursor patent. This is aimed at a compact design of the axial piston pump, wherein a swash plate is used, which rotates in an oil-filled pump housing. Towards the electric motor while a shaft seal on the motor shaft is provided, and immediately adjacent to a swash plate support bearing.

In unfavorable operating conditions, eg. B. in inclined positions of the high-pressure cleaner, this can lead to a lack of lubrication of this swash plate support bearing, so that this can lead to bearing damage. In particular, at higher speeds of the pump and thus fast rotating swash plate can lead to a suction of the lubricant from the storage area, so that lack of lubrication may occur.

It is an object of the invention to improve such a piston pump with simple means in terms of durability and safe operation.

This object is achieved with a piston pump according to the features of claim 1. Preferred embodiments are subject of the dependent claims.

By arranging an oil passage at the end of the motor shaft (in the area of the swash plate), lubricating oil is always supplied into the narrow space between the shaft seal and the swash plate support bearing. Thus, the formation of negative pressure in the storage area and thus a lack of lubrication is avoided.

Preferably, the oil passage is formed by a central longitudinal bore (in the motor shaft end region or in the region of the swash plate) and at least one transverse bore branching off from it. In a simple design, the transverse bore extends through the median plane of the motor shaft, so that the rolling elements of the bearing are lubricated directly. In this case, a plurality of transverse bores may be provided which are relatively easy to manufacture.

In a preferred embodiment, the swash plate support bearing is designed as a tapered roller bearing, wherein the transverse bore leads exactly into the relatively narrow space between the bearing and shaft seal. This also a relatively simple installation and compact design is achieved.

The following description of a preferred embodiment of the invention serves in conjunction with the drawings for further explanation. Hereby show:

1 a sectional view of a high-pressure pump with swash plate drive; and

2 an enlarged view of the "hollow drilled" motor shaft end of 1 ,

In the 1 illustrated high-pressure pump 1 includes an electric motor (here partially illustrated) 2 , on the motor shaft 2a a swash plate 3 Is arranged rotationally fixed (via a feather key). The swash plate 3 is from a pump housing 4 surrounded, on the front side of a lid 5 is mounted. The lid 5 has several piston guides 6 on, in which (usually a total of three) pistons 7 are displaceable, each by compression springs 8th to the swash plate 3 are acted upon. The pistons 7 dive - in a conventional manner - cyclically into a pump head with the ends pointing to the right 9 one. For fast rotating swash plate 3 occurs a significant Abschleuderwirkung the filled lubricating oil, so that possibly even oil from the area of the support bearing 3a can be sucked off. It can even air through a shaft seal 2 B be nachgesogen.

According to innovation, the motor shaft 2a at its right end (in the area of the swash plate 3 ) at least one oil passage 2c to the swash plate support bearing 3a This also includes the storage of the motor shaft 2a serves. This oil passage 2c is in a simple design by a central longitudinal bore (starting from the right here, front end of the motor shaft) and at least one branching off transverse bore 2d is formed. Preferably, the transverse bore extends 2d symmetrical through the midplane of the motor shaft 2a through, also for reasons of engine balancing.

The transverse bore 2d opens in the plane between the shaft seal 2 B (to the electric motor 2 towards) and the swashplate support bearing 3a so that the lubricating oil can flow centrally and directly to the support bearing 3a arrives. The shaft seal 2 B and the swashplate support bearing 3a are each arranged on a motor shaft collar, which is fine machined, in particular ground.

This also for the storage of the motor shaft 2a serving swash plate support bearings 3a is designed here as a tapered roller bearing, which over the oil passage 2c always lubricated safely. Blistering in this area (air pulling through the shaft seal 2 B ) is thus countered in a simple, but effective way, so that the Storage is effectively protected against a lack of lubrication.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 4636146 [0002]

Claims (6)

Piston pump for a high-pressure cleaning device with an oil-filled pump housing, in which a plurality of pistons are arranged, which are acted upon by a swash plate, which is driven by a motor shaft, characterized in that the motor shaft ( 2a ) in the region of the swash plate ( 3 ) at least one oil passage ( 2c ) to the swash plate support bearing ( 3a ). Piston pump according to claim 1, characterized in that the oil passage ( 2c ) by a central longitudinal bore and at least one branching transverse bore ( 2d ) is formed. Piston pump according to claim 2, characterized in that the transverse bore ( 2d ) through the median plane of the motor shaft ( 2a ) passes through. Piston pump according to one of claims 1 to 3, characterized in that the transverse bore ( 2d ) in the plane between shaft seal ( 2 B ) and swashplate support bearings ( 3a ). Piston pump according to claim 4, characterized in that for the shaft sealing ring ( 2 B ) and the swash plate support bearing ( 3a ) each a motor shaft collar is provided, which is fine machined, in particular ground. Piston pump according to one of the preceding claims, characterized in that the swash plate support bearing ( 3a ) is designed as a tapered roller bearing or as a shoulder bearing.

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