Roller bearing construction

A housing for friction and antifriction bearings comprises a cavity defined in the bearing housing between roller bearing 6 which has at least one bounding wall which is elastic and exposed on one side to the internal pressure of a lubricating chamber and on its opposite side to the exterior of the housing.

BACKGROUND OF THE INVENTION 
1. Field Of The Invention 
This invention relates in general to the construction of bearing housings 
and in particular to a new and useful bearing housing which includes an 
interior cavity for receiving a lubricant and which has a resilient 
bounding wall which is exposed on one side to the lubricant and on the 
opposite side of the exterior of the housing. 
2. Description Of The Prior Art 
In a construction of bearing housings for friction and antifriction 
bearings there is usually a lubricating cavity which is filled completely 
or partly with grease oir oil. Such bearing housings in the broadest sense 
of the term include those which accommodate two bearings or running wheels 
or races which are spaced from each other at a great distance and which 
include two inner bearing portions. In bearing housings which are exposed 
to high temperatures particularly for running wheels of grate cars for 
sintering machines it is not unusual for the content of the cavity to 
expand greatly due to the strong increases of temperature and the 
resultant thermal expansion. With the known constructions, such an 
increase of volume of the contents is prevented and excess pressure is 
produced at the interior of the housing. In practice however the bearing 
seals seldom withstand this internal pressure so that either air or grease 
is expelled depending on what is present at the leak. With a decreasing 
volume an underpressure is produced due to the closed lubricating chamber 
construction by which air or grease which has become dirtied by the 
surrounding atmosphere is sucked back into the cavity. Because of the 
so-called pumping action dirt from the outside passes continuously into 
the interior of the bearing housing. 
SUMMARY OF THE INVENTION 
The present invention provides a bearing housing for antifriction or plain 
bearings in which the volume of the inner space is permitted to vary in 
accordance with the volumetric expansion or diminution. Such a 
construction is obtained in accordance with the invention by providing at 
least one wall of the cavity which is an elastic wall and exposed on at 
least one of its sides to the exterior pressure of the atmosphere. Due to 
this construction the content of the housing cavity can expand or contract 
in almost a pressureless manner without expelling or taking in air or 
grease. 
Accordingly it is an object of the invention to provide a housing for 
friction and antifriction bearings which comprises a housing with an 
interior cavity defining a lubricating chamber having a resilient wall 
bounding at least one side of the cavity and which is exposed on its 
opposite side to the outside pressure. 
A further object of the invention is to provide a bearing housing 
construction which is simple in design, rugged in construction and 
economical to manufacture. 
The various features of novelty which characterize the invention are 
pointed out with particularity in the claims annexed to and forming a part 
of the disclosure. For a better understanding of the invention, its 
operating advantages and specific objects attained by its uses, reference 
should be had to the accompanying drawing and descriptive matter in which 
there are illustrated preferred embodiments of the invention.

GENERAL DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to the drawings in particular the invention embodied therein 
comprises in FIG. 1 a housing generally designated 10 which comprises a 
cylindrical member having a closed end 10a and an opened end 10b for 
receiving an end 12 of a shaft to be supported therein. The housing 
contains first and second roller bearing race assemblies 14 and 16 which 
engage the shaft portion 12 at spaced axial locations. The interior of the 
housing 10 includes a lubricating cavity 18 which is bounded at the inner 
side by a sleeve 20 which fits over the shaft 12 and it includes at least 
one bounding wall 1 which is made of an elastic material such as a rubber 
tube. The cavity contains grease and air and the rubber tube 1 is mounted 
by spaced split snap rings 2a and 2b which expand and firmly hold the 
resilient rubber tube 1 against the interior wall of the housing 10. 
In accordance with the invention at least one side of the elastic bounding 
wall 1 is exposed to the atmosphere or the outside pressure and in the 
embodiment of FIG. 1 this is effected by communicating a cavity portion 
18a which is located on one side of the elastic member 1 through a bore 3 
which leads to the atmosphere. Preferably a filter 4 is positioned at the 
entrance to the bore 3 to insure that only clean air passes through the 
passage. 
Thus with the invention even though the cavity 18 is filled with grease and 
air any variation of temperature to increase or decrease the volume of the 
materials will be accommodated by flexing of the rubber tube 1 without 
permitting the grease or air to escape or to be taken in through packing 7 
which is arranged between the race assembly 14 and the outside end 10b of 
the housing 10. 
In the embodiment of FIG. 2 similar parts are similarly designated but with 
a prime added. In this embodiment the lubricating cavity 18' is not 
divided by a resilient member 1 but instead it carries an elastic tubular 
member 5 which has in respect to the other embodiment at least one wall 
which expands and contracts to accommodate for any changes in the volume 
of the lubricating material contained on the interior 5a thereof. Since 
the interior 5a communicates through a bore 3' and a filter 4' to the 
outside this construction also includes at least one surface of the 
resilient member namely the elastic tube 5 which is exposed to the outside 
pressure. In the event of any temperature changes the pressure within the 
lubricating chamber 5a is equalized as in the other embodiment through the 
bore 3' and the filter 4'. This makes it possible to increase or reduce 
the interior space of the bearing housing in accordance with volumetric 
variations. In the construction of FIG. 2 the elastic tube 5' has a nipple 
1' which fits into an accommodation of the housing to communicate only 
with the bore 3'. 
While specific embodiments of the invention have been shown and described 
in detail to illustrate the application of the principles of the 
invention, it will be understood that the invention may be embodied 
otherwise without departing from such principles.