Automatic oiling device

An automatic oiling device for delivering oil to a bearing comprising a sealable container defining a reservoir for oil with a opening in which a hollow tube is fitted. One end of the hollow tube communicates with the interior of the sealable container and the other end is open. Wicking material is located in the hollow tube and extends into the interior of the sealable container at one end and extends from the other open end of the hollow tube for contact with a bearing to be oiled. The hollow tube and the wicking material co-operating to function as an automatic valve to release oil from the sealable container as needed by the bearing. The wicking material is packed into the hollow tube to a density sufficient to allow for an automatic valving cycle that controls the flow of oil. The automatic valving cycle involves capillary flow of the oil from the reservoir through the wicking material to the bearing, the flow of oil lowering pressure in the sealable container which eventually results in the capillary flow being curtailed, whereupon the lowered pressure in the sealable container is sufficient to draw air through the wicking material and into the sealable container to increase the pressure in the sealable container such that capillary flow resumes and the automatic valving cycle is repeated.

FIELD OF THE INVENTION 
This invention relates to an automatic oiling device for lubricating 
bearings and the like. 
BACKGROUND OF THE INVENTION 
Proper lubrication is an important part of ensuring that bearings run 
smoothly and trouble free. Particularly in the plumbing industry, where 
sleeve bearing electric motors and water circulator pump bearings are 
common, there is a constant problem with bearing failures. The main cause 
of bearing breakdowns is usually insufficient or improper manual 
lubrication. Manual oiling is often forgotten or, because of a range of 
factors that affect oiling requirements such as temperature, continuous or 
intermittent operation and altitude, is done improperly. 
Prior art devices have been developed that allow for automatic oiling or 
greasing of bearings to alleviate the problem of insufficient lubricating. 
Generally, these devices employ wick lubricators that are mounted atop the 
bearing to be lubricated and deliver oil or grease from a reservoir to the 
bearing packing system or directly to the bearing surface. Examples of 
such prior art lubricating devices are shown in the following United 
States patents: 
U.S. Pat. No. 133,316 to Hutchinson, Jr. 
U.S. Pat. No. 518,058 to Finch 
U.S. Pat. No. 746,243 to Baggaley 
U.S. Pat. No. 817,084 to Moore et al. 
U.S. Pat. No. 955,608 to Shortt 
U.S. Pat. No. 983,025 to Chalmers 
U.S. Pat. No. 1,171,681 to Weckwerth et al. 
U.S. Pat. No. 1,328,209 to Sharp 
U.S. Pat. No. 1,409,644 to Baker 
U.S. Pat. No. 1,632,874 to Blount 
U.S. Pat. No. 2,185,622 to Bauman 
U.S. Pat. No. 2,850,336 to Dochterman 
The majority of these devices rely on simple capillary flow of lubricating 
material through the wicking material to deliver a constant flow of 
lubricant to the bearing. In fact, the oiling device of Dockterman relies 
on a spring pressurized oil reservoir to constantly feed oil through the 
wicking material. All the devices of the prior art adequately address the 
problem of insufficient lubrication of a bearing by providing a device 
that is always in place. However, a new problem arises in that the prior 
art devices tend to supply lubricant to the bearings whether it is needed 
or not leading to wastage of lubricant and making a large lubricant 
reservoir necessary for long periods of unattended operation. 
The prior art devices known to applicant date back to the early part of 
this century and are clearly intended for large scale machinery where 
large amounts of lubricating material is necessary. 
Accordingly, there is a need for a smaller scale oiling device that can be 
used to lubricate the sleeve bearings of today's smaller electric motors 
and similar bearings. The smaller scale of these motors and their often 
intermittent operation makes supplying a constant flow of lubricant to the 
bearing unnecessary and undesirable. In recent years, electric oilers have 
been developed that employ a valve to release a small quantity of oil at 
timed intervals preset by the operator, but these devices are complex and 
very expensive to purchase and install. 
SUMMARY OF THE INVENTION 
The present invention provides an inexpensive and easily installable 
automatic oiling device that has no moving parts and automatically meters 
oil to a bearing as needed to avoid the problem of over oiling. 
The apparatus of the present invention is an automatic oiling device for 
delivering oil to a bearing comprising: 
a sealable container defining a reservoir for oil, said container having an 
opening therein; 
a hollow tube having first and second ends, said first end extending from 
said opening and communicating with the interior of said sealable 
container and said second end being open; 
wicking material in said hollow tube that extends into the interior of said 
sealable container at said first end and extends from said open second end 
of said hollow tube for contact with a bearing to be oiled; 
said hollow tube and said wicking material co-operating to function as an 
automatic valving means to release oil from said sealable container as 
needed by said bearing, said wicking material being packed into said 
hollow tube to a density sufficient to allow for an automatic valving 
cycle that controls the flow of oil involving capillary flow of said oil 
from said reservoir through said wicking material to said bearing, said 
flow of oil lowering pressure in said sealable container which eventually 
results in said capillary flow being curtailed whereupon the lowered 
pressure in said sealable container is sufficient to draw air through said 
wicking material and into said sealable container to increase the pressure 
in said sealable container such that capillary flow resumes and the 
automatic valving cycle is repeated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
An automatic oiling device 2 according to the present invention is shown in 
the single FIGURE. The device comprises a sealable container 4 defining a 
reservoir for a lubricating material such as oil. The upper end 6 of the 
container is threaded and accepts a removable screw cap 8. The container 
is moulded with an upper sealing shoulder 9 that supports O ring 10 to 
ensure that the container is properly sealed when screw cap 8 is tightened 
into place atop the sealing shoulder. Preferably, container 4 is formed 
from clear, high impact nylon and O ring 10 is made from nitril rubber. 
The lower end 12 of the container is formed with a central opening 14. A 
hollow tube 16 extends from the opening and communicates the interior of 
the sealable container with the exterior. First end 18 of tube 16 is 
located in opening 14 while the second end 20 of the tube is open and 
extends outwardly from the lower end of the sealed container. It is not 
necessary that opening 14 be centered in the lower end of the container. A 
non-centered opening often allows for easier installation in restricted 
areas. 
Hollow tube 16 is packed with wicking material 22. The wicking material 
extends into the interior of the sealable container at central opening 14 
and extends from open second end 20 of the hollow tube to provide a 
passageway for the oil. The wicking material contacts the bearing to be 
oiled when in an operating position. 
As shown in the FIGURE, current sleeve bearing designs generally use a 
fibrous packing system of all felt packing or a combination of permawick 
and felt packing. Permawick is a porous ground material that is mixed with 
oil. The sleeve bearing packing 25 acts a reservoir for oil and a felt 
wick 26 protrudes from the reservoir packing through a slot and makes 
contact with the revolving shaft or journal 28 within the sleeve bearing. 
The sleeve bearing is provided with an oil hole (not shown) that allows 
access to the fibrous packing system. Hollow tube 16 is designed to be 
inserted into this oil hole to provide oil to the fibrous packing system. 
Alternatively, the wicking material protruding from end 20 of tube 16 can 
be placed directly in contact with the rotating shaft. 
Wicking material 22 is preferably strands of 100 percent wool having a 
gauge/tension designation of 14 sts.-18 rows=4 inches according to the 
standard identification method of the wool industry. This standard 
identification method refers to knitting a standard test pattern of 14 
stitches (sts.) in 18 rows to create a pattern that is 4 inches long if 
knitted at the correct tension. The wool strands are inserted within 
hollow tube 16. 
Wicking material 22 and hollow tube 16 cooperate to function as an 
automatic valve to release oil from the sealable container as needed by 
the bearing. Wicking material 22 is packed within hollow tube 16 to a 
density sufficient to lead to an automatic valving cycle being created in 
the automatic oiling device of the present invention. This automatic 
oiling cycle is best understood by following the steps necessary to set up 
the automatic oiling device and the actual operation of the device once 
set up. 
The initial step involves filling sealable container 4 to a level shown by 
an indicator line marked on the container just above seating shoulder 9. 
In the Figure, this indicator line is covered by screw cap 8. It is 
important that the sealable container be filled to the indicated level so 
that the automatic valve cycle can be properly established. 
Screw cap 8 is then tightened down against O ring 10 and seating shoulder 
9. Preferably, screw cap 8 is formed within a raised internal surface 30 
that fits within the sealable container when the cap is tightened in 
place. Internal surface 30 acts to displace oil in the sealable container 
thereby applying a slight pressure to the contents of the container. 
Hollow tube 16 of the automatic oiling device is then inserted into the oil 
lubrication hole of a sleeve bearing bracket to be lubricated. The wicking 
material 22 protruding from the hollow tube must contact the bearing to be 
lubricated or the sleeve bearing packing. If a screw cap 8 having an 
raised internal surface 30 is tightened onto the sealable container, the 
resulting pressurization of the oil will tend to force oil down through 
the wicking material within the hollow tube so that oil actually drips 
from the wicking material initially. This allows for immediate delivery of 
oil to a bearing and ensures that a dry bearing will receive immediate 
lubrication. It has been found with prototype oiling devices according to 
the present invention that oil will start to drip within 10 minutes of the 
screw cap being tightened and continue dripping for approximately fours 
hours supplying 18-20 drops of oil in total. 
Eventually, the oil level in the sealable container will drop so that the 
oil is no longer under pressure. Alternatively, the oil may not have been 
pressurized using a cap having a raised internal surface. At this stage, 
the automatic valving cycle of the present apparatus comes into play. Oil 
travels through the wicking material by capillary action to be delivered 
directly to the bearing or to the bearing packing. O ring 10 prevents air 
from entering sealable container 4 about screw cap 8. Therefore, as oil is 
delivered to the bearing and the level in the sealable container drops, a 
low pressure area develops in the upper region of the sealable container 
just below the screw cap. This low pressure area tends to slow the advance 
of oil through the wicking material. Oil is only fed through the wicking 
material when the bearing packing or the actual bearing is dry enough that 
the resulting capillary attraction of the bearing packing or actual 
bearing is sufficiently strong to overcome the low pressure region tending 
to hold the oil in the sealable container. Eventually, as oil is used up, 
the low pressure region at the upper end of the container will prevent any 
oil from leaving the sealable container through the wicking material. The 
wicking material is packed into the hollow tube to a density such that 
when this point of no oil flow is reached, the low pressure region will 
actually draw small quantities of air up through the wicking to partially 
equalize the pressure in the low pressure region, thereby starting the 
automatic valving cycle over again. 
An automatic oiling device having the following dimensions functions in the 
desired manner. The sealable container is a cylindrical body that has an 
internal diameter of about 1.3 inches and is about 2 inches deep. The fill 
level for the sealable container is about 1.4 inches deep. When using a 
cap having a raised internal surface, the surface is dimensioned to extend 
about 0.1 inches below the level indicator when screw cap 8 is tightened 
into place in order that the oil is sufficiently pressurized. Hollow tube 
16 is about 2.7 inches long and has an outside diameter of about 0.2 
inches and an inside diameter of about 0.1 inches. The wicking material 
comprises two 8 inch lengths of wool having the previously indicated 
gauge. The lengths are folded in half to create four 4 inch long strands 
that are pulled into the hollow tube with the folded ends protruding 
approximately 3/32 of an inch. This arrangement ensures that the wicking 
material is packed to the appropriate density to establish the automatic 
valving cycle. 
With the above described arrangement, an appropriate lubricating oil for 
oiling the bearing to be treated is used. Generally, the lubricating oil 
will range from a 10 to 40 weight detergent or non-detergent oil. A 20 
weight non-detergent oil has been found to work particularly well. 
The automatic oiling device of the present invention provides a very simple 
and inexpensive apparatus for automatically oiling bearings. The device 
has no moving parts so there is very little wear. Using a transparent or 
translucent sealable container allows for easy inspection as to when the 
device requires refilling with oil. A further advantage is the great ease 
with which the apparatus of the present invention can be installed and 
maintained. 
Although the present invention has been described in some detail by way of 
example for purposes of clarity and understanding, it will be apparent 
that certain changes and modifications may be practised within the scope 
of the appended claims.