Effective Constant Level Lubrication

Oil Sump Lubrication

I ndustrial equipment including pumps, blowers, gearboxes, drives and compressors

frequently use an oil sump to lubricate, control temperature and prevent corrosion of

bearings and gears. Although it is a simple method of lubrication by design, a lack of

understanding of the basic lubrication principles will often lead to poor application

and neglect. This often leads to premature equipment failures, frequent oil changes

and increased maintenance costs. This article outlines the critical elements of oil

sump lubrication, and how to properly select and use constant level oilers to ensure

effective oil sump lubrication.

Lubrication Principles The oil sump is frequently selected by machine designers as a low-cost, low-

maintenance, low-risk approach to maintaining component lubrication. Bearings and

gears often run in sumps designed to supply a lubricant to loaded surfaces. The

lubricant prevents wear, removes heat, removes contaminants, prevents corrosion,

etc.

The oil level in a bearing or gear sump must be maintained within a narrow range to

assure that the component receives the correct amount of lubricant coverage. For

bearings, although there is some debate regarding the most effective depth of

contact, the amount of contact between the rolling element and the oil is generally

not considered a specific measurement, as long as the bearing receives a complete

coating of oil to sustain the critical oil film. However, a good rule of thumb is that the

bearing should have half of the element covered in oil when the bearing is not

turning. The most important considerations are speed, oil viscosity and load.

Gear lubrication is generally accomplished when one gear is submersed in lubricant,

which then transfers oil to the other gears, shafts and seals. In some cases, an idler

gear turns in the lubricant, transferring the oil between gears through direct contact.

A good rule of thumb for oil level for sump-lubricated gears is that the level should

completely cover the tooth of the gear sitting at the lowest position in the drive when

the gear is idle.

Figure 1. High-Low Level

If the level of lubricant in the sump is too high or too low, excessive heat will be

generated accelerating the degradation of the oil and shortening the life of the

bearing (Figure 1). When the level of oil is too high, churning occurs, which is similar

to the result of using an eggbeater when air is whipped into the oil. This, along with

the induced heat, increases the oxidation rate, shortening the effective life of the oil.

When the oil level is too low, contact is insufficient to lubricate (provide oil film) the

bearing or gear, and to act as a heat sink to carry away the normal levels of heat

generated by the bearing.

Figure 2. Opto-matic Oiler

Maintaining the Correct Level of Oil Perhaps the most widely used method of maintaining the proper lubricant level in a

bearing housing is the constant level oiler. Simple by design, the constant level oiler

replenishes oil lost by leakage through seals, vents (mist) and various connections

and plugs in the bearing housing. Once the proper level is established, replacing the

oil in the reservoir is accomplished by periodically refilling the bottle.

One such constant level oiler is the glass Opto-Matic® made by Trico Mfg. Corp.

(Figure 2). This oiler consists of a glass reservoir mounted in a die cast collar which

slides over a die cast base, or surge chamber. A beveled cap, attached to the bottom

of the glass reservoir, ensures reliable oil delivery (Figure 3). It is at the surface of

this cap that the level of oil is maintained, referred to as the control point, in both

the oiler base and the equipment-housing sump. The cap/reservoir assembly sits on

top of a level adjuster assembly that is inserted into the base, or surge chamber.

Consistent oil sump level maintenance can be achieved by properly setting the

adjuster assembly. Tightening the setscrew on the reservoir collar eliminates

movement due to vibration and handling that can cause the oiler to feed more than

needed.

Other types of constant level oilers incorporate a tubular spout. This design differs

from the glass reservoir/cap style by moving the level control point from the base of

the reservoir to the spout opening (Figure 4). It is important to understand where

the level is established in the constant level oiler in relation to the desired level in

the housing oil sump. Depending on the oiler design, a simple mark on the base can

effectively provide consistent level control.

Figure 3. Bevel on Oiler

Figure 4. Control Point on Spout Some constant level oilers are designed to be nonadjustable which eliminates the

potential of incorrect level settings. The Watchdog® oiler combines both a viewport

and oiler in one assembly (Figure 5). Because it is mounted on a port even with the

desired oil sump level, there is no requirement for adjustment.

Figure 5. Watchdog Oilers

Identifying and Correcting Problems The leading causes of incorrect oil sump levels include the following:

• Incorrect constant level oiler settings

• Pressure differentials

• Oiler location

• Shift-change syndrome

• Blocked or plugged fittings

• Improper filling methods

Incorrect Oiler Settings Review the instruction sheet provided with the oiler for a better understanding of

how to adjust and set the device for proper use. Understanding where the control

point is can greatly reduce problems associated with low or high levels of oil in the

sump. Oil temperature and viscosity can affect the feeding of oil. A meniscus forms

under the bottle, or spout of a constant level oiler before it feeds. The degree to

which this occurs depends on the oil’s surface tension (which changes as the oil

ages), and resistance to flow (viscosity) of the oil, and the oiler design. Check oil

levels in comparison to oiler settings to confirm proper adjustment under varying

viscosities and operating conditions.

Pressure Differential Airflow across equipment housings generated by fans, blowers and even the

equipment motor can be sufficient to create a pressure differential between the

bearing housing and the oiler reservoir, causing the oiler to overfill the sump -

resulting in a level that is too high. Equipment operating temperature changes can

also create pressure differentials, depending on the housing configuration including

seals, vents and oilers. In some instances, pressure can increase in the housing,

which can lower the level by pushing the sump oil back into the oiler or level sight

(when equipped). Pressure increases/decreases can be controlled by closing the

housing through the use of nonvented oilers, replacement of vents with expansion

chambers, and proper seal selections.

Oiler Location Gears and bearings create currents and flows in an oil sump housing. Depending on

viscosity and speed, the proximity of the oiler to these currents can cause unwanted

oiler feed. The most common fix for this condition is to mount the oiler either on the

opposite side of the housing, or farther away from these currents and flows.

Shift-Change Syndrome Shift-change syndrome describes how an oil sump can become overfilled by frequent

removal and replacement of the constant level oiler reservoir. Maintenance personnel

are often instructed to keep the reservoir of the oiler completely full. Tests have

shown that frequent removal and replacement of the constant level oiler reservoir

result in an increased level of oil in the equipment sump. For example, when

simulating a removal/replacement sequence once every eight hours for ten days, the

level in an ANSI style process pump was raised 1/8-inch. It is recommended that the

level of oil in the reservoir be kept half-full at a minimum, which will reduce the

number of refills. If the oiler needs to be filled frequently, locate the source of the oil

loss. This should not be considered a normal operating condition.

Blocked or Plugged Fittings It is important to check the connection fitting between the oiler and the housing to

verify that there is no blockage. When oil becomes oxidized or contaminated, it can

easily plug this fitting, which is commonly 1/4-inch NPT or smaller. If this occurs, the

oiler will not feed, and the oil level in the sump can become dangerously low. This is

easy to check by removing the oiler during oil changes and looking at the fitting

opening.

Improper Filling Methods The two most common mistakes when filling an oil sump housing are filling from the

top of the housing until the oil level is visually correct, and filling through the

constant level oiler base until it is full.

When filling from the top of the housing, it is important to know the required volume

of oil for the sump. For example, if it is known that the sump capacity is two quarts,

then it is safe to use this method for filling. If the capacity is unknown, filling from

the top until the level is verified through a sight gauge will result in a high level -

after the oil drains from the shaft, gears or other components.

Filling through the oiler base while using a sight gauge can be effective. However, if

oil is added to the oiler base until it is full, without the use of a gauge, the level in

the sump will be too high. A constant level oiler can only control the level by

replacing lost oil volume, it can’t reduce high levels.

The Watchdog-type oiler is designed for accurate filling by eliminating the adding of

oil from the housing top and combining a sight gauge for instant, accurate filling of

an oil sump.

Constant level lubricators have been used effectively to maintain the level of oil in

equipment for decades. Proper selection, installation and maintenance of these oilers

are all important aspects in achieving the desired result of reliable oil sump

lubrication. These lubricating devices help to eliminate unnecessary oil changes,

reducing equipment repairs and minimizing equipment maintenance requirements.

Constant Level Oilers - Seven Mistakes to Avoid When Installing, Applying and Refilling

Constant level oilers are designed to maintain a predetermined oil level in a sump,

which is necessary for proper lubrication. If the oil level drops below this point, the

depleted oil is automatically replenished by the lubricator, returning it to its original

level. Constant level oilers can also help increase maintenance efficiencies and

decrease maintenance costs and loss of production time. Even though constant level

oilers are simplistic and easy to install, problems can still arise. Care should be taken

when installing, applying and refilling these units.

Installation and Application Prior to installing a constant level oiler, shaft rotation direction must be determined.

If a side-mounted connection is required, the recommended placement is on the side

of the equipment, facing the direction of shaft rotation (Figure 1).

Figure 1. Side-mounted Connection

This positioning protects the oiler from oil sump surges that can occur during start-

up, which may cause the oiler to overfeed. If frequent start-ups are necessary, the

bottom-mount configuration is recommended (Figure 2). In some cases, eddy

currents and oil turbulence can form due to slinger rings, discs and high rotating

speeds. These currents can temporarily alter the level of the oil and ultimately cause

the oiler to overfeed. When these rings or discs are present, mount the lubricator

using the bottom fitting, and connect it to the bottom of the equipment’s sump

(Figure 2). Check lubricant levels periodically to ensure proper application.

Figure 2. Bottom-mounted Connection

Many oilers contain a small vertical stem. Some are fixed to the unit, and others are

part of a leveling assembly (Figure 3).

Figure 3. Level Adjustment Assembly

The purpose of this stem is to break the meniscus, allowing the oil to feed properly

through the unit. Often times, when these stems are part of a removable assembly,

they are discarded during maintenance, causing the oiler to misfeed or not feed at

all. Prior to installation, or after maintenance, verify that all parts of the lubricator

are present.

Figure 4. Cross-section of Optomatic

When using a constant level oiler that is vented to the outside atmosphere, it is

important to keep the oiler and/or the breather vent away from any air flow near the

equipment. This air flow can come from any type of fan, such as a blower or motor

fan. Fans create an air flow over the breather vent or the oiler, causing a pressure

differential between the bearing housing and the oiler, leading to misfeeding.

To prevent this, install an extension pipe nipple on either the breather vent or the

oiler connection. Replacing the vented constant level oiler with a nonvented or closed

system oiler is another solution that also eliminates contaminant ingression.

Figure 5. Pressure Differential from Air Flow

A closed system oiler’s operation and installation considerations are similar to those

of a vented oiler. However, the closed system requires a vent tube to be connected

from the lubricator to the bearing housing for pressure equalization. Also available

are additional types of closed systems oilers that mount directly on equipment that

has a port at the centerline of the oil level. This type of mounting does not allow the

fluid level to adjust, thus eliminating potential installation errors.

Figure 6. Installation of Extension Pipe

Note: When installing an extension pipe on the

vented oiler in a side-mount configuration,

do not use an elbow fitting, because this will

change the fluid level in the oil sump.

Improper Filling Methods Care should be taken when replenishing fluids to predetermined levels.

Understanding proper filling methods is important in preventing overfilling of the

sump. Although constant level oilers are simplistic in function, several mistakes are

often made, such as filling through the top or the surge body and refilling too

frequently.

When filling through the top of the equipment, knowing the required oil volume is

necessary to achieve the preset level. If the oil quantity is known, then this method

is considered to be a safe filling procedure. However, more times then not, the oil

quantity is unknown and the oil is haphazardly poured through the top, using a sight

gauge to determine the level. Unfortunately, this will result in a high fluid level due

to residual lubricant draining from the internal components such as a shaft or gear.

Figure 7. Closed System Opto-Matic

Proper oil volume can be achieved through the surge body when a sight gauge is

present. The sight gauge is a visual aid for achieving the predetermined fluid level in

the sump. Filling without a sight gauge can cause overfilling of the oil sump and

surge body. An indication of overfilling is that fluid begins flowing from the surge

body once the reservoir is replaced. To adjust for overfilling, drain the lubricant from

the sump until the constant level oiler begins feeding, and reaches the preset level.

In addition, excessive refilling of the reservoir will also have a negative effect on the

oil level. Each time the reservoir is removed and replaced, a small amount of

lubricant is added to the oil sump level. Over time, this will increase the fluid level.

To combat this, refill the reservoir only when it is half full or less. This will help

minimize unnecessary filling.

Figure 8. Watchdog Constant Level Oiler

Constant level oilers are an easy and effective method of maintaining proper oil level

in equipment. Proper installation and usage will provide optimum performance of the

lubricator as well as the equipment it supplies. By implementing the recommended

guidelines, efficient and effective lubrication management can be achieved.

Constant-level Oilers

A constant-level oiler is used to maintain the fluid level in a piece of equipment that

naturally depletes fluid through use, wear, friction, misting or evaporation.

As oil is depleted in equipment, such as bearings, gearboxes, pillow blocks or pump

housings due to its natural operation and the generation of heat from friction, the

level of fluid changes. A constant-level oiler can be used to maintain optimum

performance.

The operation is based on the liquid seal principle: as fluid is depleted in the

equipment, the liquid seal on the spout inside the constant-level oiler is broken.

When this occurs, air enters into the oil reservoir from the air vent. This releases the

fluid from the reservoir and allows it to flow into the equipment until the liquid seal

reestablishes itself.

An automatic constant-level oiler can be used for antifriction, sleeve, roller, ball,

tapered, spherical or slinger bearings involving excessive backpressure. Applications

include fans, motors, blowers, gearboxes or other equipment where a constant level

of fluid needs to be maintained. Constant-level oilers are most useful in paper mills,

cement plants, coal handling mills or industries with similarly dirty environments,

because the sumps are opened less frequently.

Basic Design and Operation In situations where pressure or a vacuum is generated in the sump, it is preferable

to provide a vent line back to the equipment housing above the oil level to equalize

the pressure. By equalizing the pressure between the oiler and the equipment

(Figure 1), the level is more accurately maintained, creating a closed-loop system. In

the event that there is no place to pipe the air vent back to the equipment, a filtered

vent plug at the reservoir can be used to prevent environmental contaminants from

entering the system. Figures 2 and 3 show the two fluid connection points, of which

either point can be used for installation or drain. One is located on the side of the

housing while the other one is on the bottom. These points will vary by design.

Figure 1. Style CS

The liquid level in the oil reservoir is visible through a clear reservoir available in

acrylic or glass and in various sizes. Maximum temperature rating is 160ºF for acrylic

and 225ºF for glass. The reservoir is mounted airtight on the base to prevent

contaminants from entering. The reservoir is easily refilled through the cap on top

port which will automatically shut off the flow while being refilled. Operation will

resume when the cap is returned and secured. It may be necessary to repeat the fill

process until the fluid reaches the optimum level and no longer drains from the

reservoir when the cap is installed.

Constant level oilers may be installed remotely or directly to the reservoir. A liquid

level line is marked on the base of the constant-level oiler for ease in aligning to the

proper oil level.

Figure 2. Style CS Adjustable

With certain equipment, high levels of oil can be carried to the upper portion of the

housing during operation. Upon shutdown, this oil surges back to the reservoir

establishing a high oil level. Should this amount of oil overtake the capacity of the

reservoir, it will flow into the vent line (Style CS) and dissipate or in the case of

those piped to the sump through the vent line, will run back to the housing.

A constant level oiler is installed with the oil level mark at the exact height at which

the fluid in the housing is to be maintained. It should be level with short, rigid

connections to avoid vibration. The air vent is sometimes equipped with a filter when

vented to the atmosphere. The air vent can also be connected back to the top of the

gearbox or housing for a closed circuit.

Constant level oilers have been known to operate for years or even decades without

maintenance. Degraded seals are the most likely cause of an operating problem. The

oiler can be tested by plugging the fluid outlets with pipe plugs, refilling the

reservoir, tightening the cap and observing for leakage. The oil should seek and stay

at the oil level mark over the course of several hours. If the seals are faulty, the oil

will fill the viewing port and seep out the vent hole. In the case of faulty seals, it is

advisable to replace the entire unit.

Figure 3. Style C

Installation Proper installation of the oiler will assure maximum long-term operation. Key issues

that must be addressed during installation include:

1. Verify that the oil level is clearly marked on the base of the oiler. Mount the

oiler by using side or bottom outlet at the desired level.

2. The correct oil level is the lowest level at which the bearing operates properly,

which should be at the middle of the element measured at the six o’clock

position in the race.

3. Lubricator must be level in all directions to function properly.

4. All connecting pipes should be short, rigid and close to the housing to avoid

vibration.

5. Assure that the housing is filled at initial installation. Fill the housing through

the oiler. Repeated filling may be necessary.

6. Verify that the filler cap is tightly fastened. Removing the filler cap will shut

off oil supply. Loose filler cap will cause leakage.

7. The sump should be fitted with sight glass to confirm oiler operation.

Troubleshooting A variety of table-top tests may be conducted to identify and resolve issues in the

installation and maintenance of constant level oilers. A simple preventive

maintenance inspection can be conducted as follows:

1. Secure oiler so it is level in all directions.

2. Plug outlets with pipe plugs.

3. Remove fill cap and fill reservoir completely.

4. Quickly screw fill cap back on the reservoir. Note: Closing the fill cap allows

the check valve to open, thus allowing oil to fill the sight glass.

5. When the fill cap is tightened securely, the oil in the sight glass should seek a

level at or near the level mark shown in the casting.

6. Leave oiler to sit for several hours. If it continues to hold oil at the initial

level, the oiler is working properly. If oil appears to be filling the sight glass

completely, and is seeping out of the vent hole, the seals in the unit are bad

and the seals should be replaced.

A constant level oiler is disclosed which includes an adjustable nozzle assembly for

establishing the operating or working level of the oil lubricant in the oil chamber and to a

user assembly. A tool is further disclosed which is insertable into the oiler chamber for

making the desired nozzle assembly adjustments.

1. For use with a constant level oiler having a nozzle assembly and a bottom opening

providing access to the nozzle assembly, said nozzle assembly including a tubular

member supported in the oiler and being threaded exteriorly, an internally threaded spout

member engageable on the free end of said tubular member and projecting axially

downward beyond the end of the tubular member, and a hollow lock nut threadedly

engaged within the spout member and adapated to abut on the end of the tubular member

to lock the spout member relative to the tubular member; a spout member adjustment tool

insertable through the bottom opening of the oiler and including a wrench engageable

within the opening of the lock nut, a sleeve on said wrench engageable with the spout,

said wrench and sleeve being separately manipulatable to first rotate the lock nut and

thereby free the spout member for rotation, rotate the spout member to effect adjusting

movement vertically to a new position of adjustment, and thereafter rotate the lock nut to

again abut the end of the tubular member and thereby relock the spout member in its

newly adjusted position.

2. The structure as set forth in claim 1 wherein the end of the spout member that projects

downwardly beyond the end of the tubular member is provided with at least one

vertically extending notch, and the end of the tool sleeve engageable with the spout

member is provided with at least one radially projecting prong engageable within the

notch of the spout member.

3. The structure as set forth in claim 1 wherein the end of the spout member that projects

downwardly beyond the end of the tubular member is provided with a plurality of

vertically extending notches, and the end of the tool sleeve engageable with the spout

member is provided with a plurality of radially projecting prongs corresponding to and

engageable within the notches of the spout member.

BACKGROUND OF THE INVENTION

This invention relates to a constant level oiler with an adjustable nozzle assembly for

establishing the operating or working level of the oil lubricant to a user assembly, and to

a tool for making nozzle asembly adjustments.

Most constant level oilers formerly were not adjustable to establish the working level of

the oil lubricant to a user assembly. When a remote mounting for the oiler was provided,

the mounting height could be altered to attain an adjustment. When remote mounting was

not provided, ane the level of the oil lubricant was to be raised, the constant level oiler

could be disassembled and its nozzle shortened as by filling. At other times the direct

mounting tube had to be altered or replaced to make a needed adjustment. Generally,

installation of a new oiler, or an adjusting alteration of an existing installation, proved to

be a time consuming job.

The oilers that were adjustable are provided with a telescoping oil chamber wherein the

reservoir along with a fixed nozzle and oil chamber bonnet are movable as a unit to adjust

the working level of the oil lubricant. In these oilers set screws fastened externally

secure the movable unit in adjusted position. Generally, the arrangement is suited only to

oilers of relatively small reservoir capacity and is not tamperproof.

It is generally an object of this invention to provide a constant level oiler which is

adjustable to establish the working level of the oil lubricant to a user assembly for most

any size of reservoir, and because the adjustment is made internally of the oiler, it will be

tamperproof.

SUMMARY OF THE INVENTION

The invention is directed to a constant level oiler having an oil lubricant chamber. A

nozzle assembly is supported at its upper end within the oiler and projects downwardly

into the chamber and serves to establish the working or operating level of the oil lubricant

in the chamber. The nozzle assembly comprises a pair of threadedly engaged tubular

members with one of the members projecting downwardly beyond the end of the other of

said members and is movable vertically relative to the other of said members to provide

for adjustment of the operating level of the oil lubricant in the chamber. Means are

further provided to lock the nozzle assembly members in any desired position of

adjustment.

The invention further resides in a tool for making an oil lubricant level adjustment in the

chamber of the constant level oiler. The tool is insertable through a bottom opening

aligned with and providing access to the spout of the nozzle assembly. The tool includes

first means engageable with the lock means and a second means engageable with the

spout. The first and second means of the tool are separately manipulatable to initially

unlock the lock means, effect and adjusting movement of the spout to a new position of

adjustment, and thereafter to relock the spout relative to the nozzle assembly.

DESCRIPTION OF THE DRAWING FIGURES

The drawings furnished herewith illustrate the best mode presently contemplated for

carrying out the invention and are described hereinafter.

In the drawings:

FIG. 1 is a side elevation partially in section of a constant level oiler provided with a

nozzle assembly having an adjustable spout;

FIG. 2 is a view taken generally on lines 2--2 of FIG. 1 and shows the adjustable spout in

factory set position and in dashed lines generally indicates the range of possible

adjustment for the spout;

FIG. 3 is a side elevation partially in section and shows a constant level oiler as generally

installed for lubricating a bearing and with pressure equalized between the oiler and

bearing;

FIG. 4 is a side elevation partially in section of a tool for adjusting the spout of the nozzle

assembly to provide for the proper oil level for lubrication;

FIG. 5 is an exploded view of the tool of FIG. 4;

FIG. 6 is an enlarged end elevation of the tool taken generally on line 6--6 of FIG. 4; and

FIG. 7 is a sectional view showing the tool of FIG. 4 in engaged position to make a

desired adjustment for the spout.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT

Referring to the drawings, the constant level oiler 10 of FIG. 1 provides for and maintains

a constant level of oil lubricant in a user assembly, now shown, such as a bearing, gear

case, pillow block, etc.

The oiler 10 includes an oil supply reservoir 11 provided with a hollow threaded base

fitting 12 for mounting engagement within the threaded opening 13 of the hollow lower

body 14. Oil from the reservoir 11 passes through a plurality of passages 15 in the base

fitting 12, the body opening 13, and the nozzle assembly 16 into the oil chamber 17 of the

body 14. The level of the oil in chamber 17 may be observed through the sightglass 18.

The reservoir 11 is provided with a tubular column 19 centrally having a bore 20 therein.

The stem 21 of a closure valve 22 is slidably disposed in the bore 20 and is normally

biased to close the valve against the annular seat 23 in the base fitting 12.

The oil in the reservoir 11 is replenished through an upper opening which is closed by the

filler cap 24. When the filler cap 24 is removed, the valve 22 is biased to the closure

position against the seat 23 so that the oil level in chamber 17 and the user assembly

remains unaffected during oil replenishment. When the filler cap 24 is replaced in closure

position, a downwardly extending projection, not shown, extends from the cap 24 into the

bore 20 and engages with the upper end of the valve stem 21 to reopen the valve 22 and

reestablish communication between the reservoir 11 and the chamber 17. The reservoir

11 and the passage to and through the nozzle assembly 16 must be airtight for the proper

operation of the oiler 10.

The body 14 is provided with a threaded opening 25 in the base thereof somewhat larger

and in alignment with the free end of the nozzle assembly 16. The opening 25 is normally

closed by a threaded plug 26. The chamber 17 communicates with the user assembly

through the tubular member 27 which is secured to the body 14 by the threaded fitting 28

engaged in the side opening 29. The side opening 29 is provided relatively low in relation

to the chamber 17. The chamber 17 is also vented to the atmosphere through the threaded

opening 30 in the body 14 into which a filter fitting 31 is normally engaged to preclude

the entry of any deleterious matter. The vent opening 30 is generally placed as high as

possible relative to chamber 17 to provide an adequate capacity for oil that surges back

into the chamber upon shut-down at the user assembly.

The nozzle assembly 16 of the oiler 10 includes a funnel-shaped nozzle member 32. The

member 32 is provided with an annular radial flange 33 exteriorly and adjacent to the

relatively wide mouth thereof for seating on the annular shoulder 34 provided in the

stepped opening 13 of the body member 14. The member 32 is held in place by the lower

end of the base fitting 12 with an O-ring seal 35 wedged therebetween.

The lower cylindrical portion of the funnel-shaped member 32 is threaded externally to

receive the internally threaded spout member 36 on the end thereof. The free open end of

the spout member 36 is provided with a pair of diametrically opposed, generally

rectangular recesses or notches 37 the upper ends of which establish the desired operating

level of the oil lubricant in the chamber 17 and the user assembly. The width of the

notches 37 is also believed to determine the size of the air bubbles vented into the

reservoir 11 when the liquid seal along the upper edge of the notches is broken as the oil

level in chamber 17 drops because of oil consumption in the user assembly. When the

liquid seal at the notches 37 is broken, the air vented into the otherwise airtight reservoir

11 releases adequate oil lubricant to reestablish the liquid seal and thereby maintain the

oil level in the chamber 17 generally constant.

The spout 36 is adjustable relative to the funnel-shaped member 32 as indicated by the

dashed lines in FIG. 2 which generally show the range of possible adjustment. The solid

line position of FIG. 2 generally indicates the factory set position which is about midway

relative to the range of possible adjustment. An annular exteriorly threaded lock nut 38 is

threaded inside the spout member 36 to engage the lower end of the member 32 with a

sealing ring 39 wedged therebetween to lock the spout member relative to the member 32

in any position of adjustment.

The constant level oiler 40 of FIG. 3 is similar in many respects to the oiler 10 of FIG. 1

and like reference numerals are used to designate parts that are generally the same.

In the oiler 40 the reservoir 11 is mounted on a lower body 41 having no sightglass for

viewing the interior of the chamber 42. The threaded bottom opening 25 of body member

41 is closed by a longer threaded plug 43 adapted to receive the nuts 44 and 45 for

securing a mounting member, shown in part, therebetween to mount the oiler 40 remote

but generally adjacent to the user assembly.

The oiler 40 is shown installed to provide oil lubricant for an anti-friction bearing 46, the

lower end of which communicates with the chamber 42 through the tube 27. As was

described relative to the oiler 10, the oil lubricant level in the bearing 46 is established by

the height or level of the upper edges of the notches 37 of the spout member 36 in

chamber 42 of the oiler 40. In the installation of FIG. 3 the pressure in the bearing 46 and

the chamber 42 are equalized through the tube 47 which extends from the upper portion

of the bearing housing for connection to the vent opening 30 in the bodh 41 by the

threaded fitting 48.

The factory set position of the spout member 36 in the oilers 10 and 40 may not accord

with the needs of the customer, making some adjustment of the spout member relative to

the nozzle member 32 necessary. While a customer can disassemble the oiler to make the

needed spout member adjustment, such a course is not only time consuming, but is also

done at some risk of improper reassembly, particularly at the several sealed connections.

To avoid such a course, the tool 49 may be utilized to make any needed spout member

adjustment.

As shown in FIGS. 4-6, the tool 49 generally consists of two principal elements; namely,

a hex wrench 50 and a cylindrical sleeve 51. The hex wrench 50 includes a T-handle 52

providing for finger manipulation. Intermediate its length, the hex wrench 50 is also

provided with a radially reduced cylindrical section 53. The sleeve 51 is slidable over the

hex wrench 50 as generally shown in FIG. 4 and is provided with a hole 54 intermediate

its length. With the sleeve 51 disposed on the hex wrench 50, a press fit pin 55 projecting

radially through the hole 54 at the reduced section 53 of the wrench makes the sleeve

captive on the wrench but movable longitudinally thereon within limits set by the T-

handle 52 at the one end and the interference between the pin 55 and the enlarged hex

portion of the wrench at the free or working end of the tool 49. The assembled hex

wrench 50 and sleeve 51 are separately rotatable either clockwise or counterclockwise.

The end portion of the sleeve 51 adjacent to the T-handle 52 is provided with a knurled

portion 56 to provide for easy finger manipulation. Adjacent to the opposite or working

end of the sleeve 51, a pair of diametrically opposed prongs 57 project angularly

outwardly.

If needed, adjustment of the spout member 36 relative to the nozzle member 32 is

ordinarily effected prior to installation of the oiler. In any event, such an adjustment must

be made when the oiler is empty of oil lubricant content.

To make an adjustment of the spout member 36 relative to the nozzle member 32, it is

necessary to open the bottom outlet 25 to permit the insertion of the working end of the

tool 49 through the opening. Initially the working end of the hex wrench 50 is engaged

within the hex opening 58 of the internal lock nut 38 and the working end of the sleeve

51 is engaged within the open end of the spout member 36 with the diametrically

opposed prongs 57 engaged with the corresponding notches 37 at the end of the spout

member as generally shown in FIG. 7.

The relative position of the end of the spout member 36 prior to adjustment can be

ascertained initially relative to a pair of axially spaced lines or marks 59 and 60

impressed on the outer surface of the sleeve 51. The space between the lines 59 and 60

corresponds to the full range of adjustment possible for the spout member 36. When the

spout member 36 is to be adjusted from the factory set position which is generally at the

midpoint of the range of adjustment, that position will be ascertainable relative to the

sleeve 51 at the exit plane 61 of the bottom outlet 25 where the exit plane extends

generally midway between the lines 59 and 60 as generally shown in FIG. 7. From the

position illustrated in FIG. 7, adjustment of the spout member 36 either up or down is

possible with the limit of adjustment being indicated when the respective lines 59 and 60

coincide with the exit plane 61.

To make an adjustment of the spout member 36 upward to raise the level of the oil

lubricant in the user assembly from the position shown in FIG. 7, the hex wrench 50 is

turned in a counterclockwise direction to loosen and adequately back off the lock nut 38

and the sleeve 51 is rotated to provide the amount of upward adjustment desired for the

spout member. After the spout member 36 has reached its adjusted position, the hex

wrench 50 is rotated in a clockwise direction to relock the spout member in the newly

adjusted position.

For an adjustment of the spout member 36 downwardly to lower the level of the oil

lubricant in the user assembly from the position of FIG. 7, the hex wrench 50 is first

again manipulated to loosen the lock nut 38 and thereafter the sleeve 51 is rotated to

provide for downward adjustment of the spout member to the level desired. When the

adjustment for the spout member 36 is completed, the lock nut 38 is again driven by the

hex wrench 50 to relock the spout member.

The invention thus provides a constant level oiler having an adjustable nozzle assembly

for establishing the operating level of the oil lubricant to the user assembly. The

invention further provides a tool that provides for easy, rapid and accurate adjustment of

the operating level for the oil lubricant fed to the user assembly by the constant level

oiler. Since only the spout of the nozzle assembly is affected in the adjustment process,

the balance of the oiler can remain standard even over a relatively wide range of reservoir

sizes. Since the adjustments are made interiorly of the oiler, the settings are generally

tamperproof.

Various modes of carrying out the invention are contemplated as being within the scope

of the following claims particularly pointing out and distinctly claiming the subject

matter which is regarded as the invention.