The invention relates to a reciprocating piston mechanism such as an air-conditioning compressor for motor vehicles, which has a housing, a rotary driven shaft, a shaft-sealing device, in particular a gliding ring seal, at least one radial shaft bearing, in particular a radial roller bearing, and at least one axial shaft bearing, in particular an axial roller bearing. Reciprocating piston mechanisms of this type, which are used for air-conditioning systems in motor vehicles, belong to the known state of the art. Inside the housing or in components of the housing there are bearings for the rotary driven shaft which drives a mechanism that is arranged within the housing and serves to compress the refrigerant. Because the swash-plate, tilting plate, or wobble-plate device in a piston-drive mechanism of this type exerts both radial and axial forces on the shaft, the rotating shaft is subjected to a revolving bending deformation that is due primarily to the radial force components. As a consequence, the radial bearing is subjected to stresses and deformations which can cause increased wear as well as power losses due to increased friction, especially if the radial bearing is designed to be rigid relative to bending deformations so that it cannot adjust to the bending of the driving shaft, which results in forced internal reactions and increased friction.
Also known in the art are compressors that contain a gliding ring seal, which must be supplied with an appropriate lubricant. Depending on the design of the compressor housing and the bearings, the lubrication of the gliding ring seal requires appropriate bore channels to serve as conduits for the lubricant inside the housing. In terms of manufacturing technology, bore channels of this type are difficult to produce in a housing.
The invention therefore has the objective to create a reciprocating piston mechanism, such as an air-conditioning compressor for motor vehicles, that is free of the aforementioned drawbacks.
The invention proposes a solution that meets this objective in a a reciprocating piston mechanism such as an air-conditioning compressor for motor vehicles, which has a housing, a rotary driven shaft, a shaft-sealing device, in particular a gliding ring seal, at least one radial shaft bearing, in particular a radial roller bearing, and at least one axial shaft bearing, in particular an axial roller bearing. According to the invention, at least the radial shaft bearing is held in a bearing sleeve that is connected to the housing and protrudes into the interior of the housing. In a preferred embodiment of the inventive reciprocating piston mechanism, the bearing sleeve can elastically bend and thereby cushion the radial shaft bearing in a radial direction. Thus, the bearing sleeve provides a combination of damping properties and bending stiffness that will favorably affect the operating lifespan of the bearing.
In a further preferred embodiment of the inventive reciprocating piston mechanism, the end of the bearing sleeve that faces away from the radial bearing has a smaller diameter and passes through a collar-shaped opening in the housing. The reduced-diameter end of the sleeve that extends out of the housing enters into a ring-shaped bearing mount for a drive pulley assembly. As an additional benefit of the invention this allows the bearing sleeve to be used as a weld pool backup for the welding of the housing and the ring-shaped bearing mount.
According to a further embodiment of the invention, the bearing sleeve can hold the axial shaft bearing. In performing this function, the bearing sleeve is distinguished by its strength and rigidity to withstand the axial forces acting on the bearing.
A further embodiment of the reciprocating piston mechanism according to the invention is characterized by lateral openings in the bearing sleeve between the sleeve section that is connected to the housing and the section that holds the radial shaft bearing. These openings serve as passages for the lubricant, and they also allow the sleeve to be designed with a specific radial stiffness through appropriate selection of the cross-sectional area of the openings of the contour shape of the sleeve. In one embodiment pursuant to the invention, the lateral openings are in the area of a shaft seal device, in particular a glide ring seal, that is arranged at least partially in the bearing sleeve.
A further embodiment is distinguished by a stepped down and/or tapered shape of the outside diameter of the bearing sleeve, in which the diameter decreases towards the end of the bearing sleeve that is nearest the housing and protrudes through the housing. As a result, lubricant that has been spun off inside the housing and has run down off the housing wall is fed to the lateral openings for cooling and lubricating the glide ring seal. The lubricant that is fed to the glide ring seal is preferably removed by way of the radial bearing.
Several embodiments of the invention will be described below with reference to the drawings, wherein
Without further analysis, the foregoing will so fully reveal the essence of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting essential generic or specific features that set the present invention apart from the prior state of the art. Therefore, such adaptations should be understood to fall within the scope and range of equivalence of the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
101 04 654 | Feb 2001 | DE | national |
This application is a continuation of International patent application Ser. No. PCT/DE01/03770, filed Sep. 26, 2001, published in German, which is hereby incorporated by reference in its entirety.
Number | Name | Date | Kind |
---|---|---|---|
2929551 | Heidorn | Mar 1960 | A |
3552886 | Olson | Jan 1971 | A |
3712759 | Olson, Jr. | Jan 1973 | A |
3945765 | Toyoda et al. | Mar 1976 | A |
4321019 | Degawa et al. | Mar 1982 | A |
4431378 | Hattori et al. | Feb 1984 | A |
4444549 | Takahashi et al. | Apr 1984 | A |
5137431 | Kiyoshi et al. | Aug 1992 | A |
5370505 | Takenaka et al. | Dec 1994 | A |
5393204 | Kawahara | Feb 1995 | A |
5483867 | Ikeda et al. | Jan 1996 | A |
5501579 | Kimura et al. | Mar 1996 | A |
5562182 | Kayukawa et al. | Oct 1996 | A |
Number | Date | Country |
---|---|---|
42 11 695 | Oct 1992 | DE |
1 065 375 | Jan 2001 | EP |
Number | Date | Country | |
---|---|---|---|
20040094031 A1 | May 2004 | US |
Number | Date | Country | |
---|---|---|---|
Parent | PCT/DE01/03770 | Sep 2001 | US |
Child | 10631500 | US |