US3502178A - Air line lubricator - Google Patents

Description

March 24, 1970 c. A. HANSSON 3,502,178

AIR LINE LUBRICATOR Filed June 6. 1967 INVENTOR.

CARI Audens Hmssw United States Patent US. Cl. 184-55 4 Claims ABSTRACT OF THE DISCLOSURE An air line lubricator comprising a casing incorporating two bowl-shaped halves joined to one another along their rim portions, a tube for the passage of compressed air therethrough and traversing said casing across said rim portions, a portion of reduced cross section in said tube, a pressure conduit for feeding air under pressure into said casing, said pressure conduit being in fixed communication with said tube at a point spaced from said reduced portion thereof and extending in coiled relation to said tube along the inner surface portions of both casing halves, and a suction conduit for sucking oil into said tube, said suction conduit being in fixed communication with said reduced portion of said tube and extending in coiled relation to an axis transverse to said tube between opposed inner surface portions of said casing halves along the inner surface thereof, said suction conduit being perforated by a plurality of fine bores spaced there along and said pressure conduit being perforated by a plurality of fine bores spaced there along, said fine bores having a diameter of between about 0.75 and 2 millimeters.

An outwardly bulging hollow air line lubricator casing containing oil is traversed by a tube for compressed air connected to said air line. Within said casing the tube is connected to an air pressure transmitting conduit coiled about the tube and extending along the inner surface of said casing and an oil suction conduit coiled about an axis transverse to said tube and extending between 0pposed inner surface portions of said casing along the inner surface thereof.

This invention relates to air line lubricators and more particularly to an air line lubricator having a casing forming an oil chamber, a tube traversing said casing for the passage of compressed air therethrough and communicating with the said casing on the one hand through a pressure conduit for feeding air under pressure to said casing and on the other through a suction conduit for sucking oil into said tube.

It is an object of the present invention to provide a rigid and lightweight lubricator which will stay tight and operate without failure during rough working conditions for example while being dragged in broken stone and squeezed by large forces.

Another object of the invention is to provide a lubricator having a large flow capacity and a more nearly linear relation between the oil delivery or dosage and the air flow volume per unit of time as compared to the usually quadratic relation between the differential pressure causing the oil delivery and the air flow volume per unit of time.

A further object of the invention is to provide a lubricator the casing of which may be easily and cheaply manufactured of sheet metal parts by welding.

With the above in view the invention consists in an air line lubricator having a casing forming an oil chamber, a tube traversing said casing for the passage of compressed air therethrough and communicating with the said casing on the one hand through a pressure conduit for feeding air under pressure to said casing and on the other through a suction conduit for sucking oil into said tube, characterized in that said casing is an outwardly bulging hollow body in which said pressure conduit is coiled about the tube and extends along the inner surface of said casing while the suction conduit is coiled about an axis transverse to said tube and extends between opposed inner surface portion of said casing along the inner surface thereof.

The invention will be described more in detail by the aid of the accompanying drawing in which FIG. 1 shows a longitudinal sectional view through a lubricator according to the invention. FIG. 2 is a perspective fragmentary view shown partly in section and partly exploded of the lubricator in FIG. 1. FIG. 3 shows a sectional view on line 33 in FIG. 1.

The lubricator in the figures consists of an outwardly bulging flattened bi-convex casing or hollow body 10 forming the oil chamber of the lubricator. The hollow body 10 is traversed by a venturi tube 11. At the opposite ends of the venturi tube 11 are welded inwardly threaded sleeves 12 into which are threaded coupling halves 13 and 14. The half 13 is intended for being sealingly connected to a compressed air hose for the delivery of compressed air, while the half 14 is connected to a hose leading to the compressed air consuming tool which shall be supplied with compressed air containing a suitable dosage of lubricating oil.

The venturi tube 11 has its smallest section at the middle portion thereof and is connected at this point to an oil control valve housing 15 including a needle valve 16. The needle valve 16 is threaded into the inner portion of the valve housing 15 and is adjustable axially therein by screwing whereby an oil delivery bore 17 may be controlled which communicates with the venturi tube 11. The outer end of the valve housing 15 projects out of the hollow body 10 and is closed by a threaded plug 18.

The hollow body 10 consists of two bowl shaped halves 20, 21 joined to one another along the rim portion thereof by welding. The halves 20, 21 preferably are rotationally symmetric with respect to a central axis perpendicular to the plane of division of the halves 20, 21. The halves 20, 21 are furthermore provided with semi-cylindrical diametrically arranged openings 22, FIG. 2, into which the sleeves 12 of the venturi tube 11 fit and are received when the halves 20, 21 are welded to. one another along their rim portions and to the sleeves 12. The upper half 21 is provided with a central opening 23 through which is passed the oil control valve housing 15 and said upper half 21 is welded thereto whereby the lubricator becomes more rigid. The upper half 21 is also provided with a threaded collar 24 for oil replenishment into which a plug 25 is threaded.

A pressure conduit 26 is fixed to and communicates with the venturi tube 11 adjacent to the sleeve 12 intended for the coupling half 13. The pressure conduit 26 is coiled about the axis of the venturi tube 11 extending in upward direction from the venturi tube transverse or perpendicular thereto and being coiled along but spaced from the inner surface of the hollow body 10 for almost a full turn around the venturi tube 11. The coil portion of conduit 26 is terminated by an upward open end 27. As illustrated in FIG. 3 the coiled portion of conduit 26 is preferably disposed in a cross plane perpendicular to the tube 11 and coincident with the center axis of the oil control valve housing 15.

A suction conduit 30 is connected as by welding to the bottom of the bowl half 20 and is coiled about the center axis of the oil control valve housing 15 following in slightly spaced relation the inner surface of the hollow body 10 by a coil which extends from the bowl half 20 upward towards the bowl half 21. The upper end of suction conduit 30 is bent inwardly-downwardly and connected to the oil control valve housing 15 for communication therewith upstream of the needle valve 16. The suction conduit 30 is provided with a plurality of fine radial bores 32 spaced along the conduit and with a diameter between 0.75 and 2 millimeters, for example 1.5 mm. in case of a suction tube having a diameter of 6 mm. The pressure conduit 26 may in similar manner be provided with fine radial bores 33 of the same magnitude.

The flattened bi-convex shape of the welded hollow body 10 is reinforced by the venturi tube 11 and the valve housing 15 and forms a lightweight rigid construction permanently enclosing and protecting the working parts of the lubricator. Compressed air is supplied to the coupling half 13 and the pressure thereof is transmitted to the interior of the hollow body 10 via the pressure conduit 26 through the end 27 and the fine radial bores 33 thereof. In the narrow middle portion of the venturi tube 11 adjacent the oil delivery bore 17 the compressed air flows with increased velocity and at a correspondingly reduced pressure. The oil in the hollow body 10 thus will be actuated by a differential pressure which, when the needle valve 16 is adjusted to the desired position in the valve housing 15, via the suction conduit 30 draws oil at the desired quantity through the bore 17 into the compressed air fiow in the venturi tube 11. In lubricators the oil quantity delivered per unit of volume of the compressed air flow should not follow the quadratic relation which is in force between the pressure differential generated in the venturi tube and the air flow volume per unit of time. The reason for this is that the oil delivery per unit of air volume in such cases would become too large causing unnecessary oil losses. However, thanks to the fine radial bores 32 of the suction conduit 30 as proved by practical trials, this quadratic relation is changed and one receives instead thereof an advantageous more linear relation between the oil dosage and the air flow volume. This follows since during operation, oil rising in the suction conduit 30 will become mixed with air which penetrates into suction conduit 30 through the uppermost radial bore holes 32, said uppermost radial bore holes 32 being those disposed in the air-filled dome portion of hollow body .10, and influence the oil flow relationship in the desired direction. The bores 32, 33 also efiectively eliminate generation of siphon action in the respective conduits 30 and 26. Unintentional emptying of the lubricator and its conduits is hereby avoided when the lubricator happens to take an abnormal position. Thus when the line pressure is relieved while the hollow body 10 is positioned upside down, the air pressure within body 10 will be immediately relieved through the then uppermost bore holes 33 in pressure line 26. This prevents the air cushion trapped in hollow body 10 from forcing large oil additions into the line conduits.

What I claim is:

1. An air line lubricator comprising a casing incorporating two bowl-shaped halves joined to one another along their rim portions, a tube for the passage of compressed air therethrough an dtraversing said casing across said rim portions, a portion of reduced cross section in said tube, a pressure conduit for feeding air under pressure into said casing, said pressure conduit being in fixed communication with said tube at a point spaced from said reduced portion thereof and extending in coiled relation to said tube along the inner surface portions of both casing halves, and a suction conduit for sucking oil into said tube, said suction conduit being in fixed communication with said reduced portion of said tube and extending in coiled relation to an axis transverse to said tube between opposed inner surface portions of said casing halves along the inner surface thereof, said suction conduit being perforated by a plurality of fine bores spaced therealong and said pressure conduit being perforated by a plurality of fine bores spaced therealong, said fine bores having a diameter of between 0.75 and 2 millimeters.

2. A lubricator according to claim 1 characterized in that said casing is of flattened bi-convex shape with said bowl-shaped halves thereof being rotationally sym metrical.

3. A lubricator according to claim 1 characterized in that along said transverse axis there is affixed a valve housing to said tube projecting through and fixed to said casing, said valve housing including an adjustable oil control valve to which said suction conduit is coupled.

4. An air line lubricator comprising a casing incorporating two bowl-shaped halves joined to one another along their rim portions, a venturi tube for the passage of compressed air therethrough and traversing said casing across said rim portions, a pressure conduit for feeding air under pressure to said casing, said pressure conduit being in fixed communication with said tube at a point spaced from the venturi throat thereof and extending in coiled relation to said tube along the inner surface portions of both casing halves, and a suction conduit for sucking oil into said tube, said suction conduit being in fixed communication with said venturi throat of said tube and extending in coiled relation to an axis transverse to said tube between opposed inner surface portions of said casing halves along the inner surface thereof, said suction conduit being perforated by a plurality of fine bores spaced therealong and said pressure conduit being perforated by a plurality of fine bores spaced therealong, said fine bores having a diameter of between 0.75 and 2 millimeters.

References Cited UNITED STATES PATENTS 1,657,597 1/1928 Terry 18455 1,688,946 10/1928 Terry 1845S 1,909,021 5/1933 Slater 18455 1,925,826 9/1933 Terry et al. 184'55 2,073,009 3/1937 Hersey et al. 18455 2,204,950 6/ 1940 Rouse 184-55 2,585,457 2/1952 Gillerstrom 18455 2,607,441 8/1952 Gillerstrom 184-55 2,646,134 7/1953 Nickens 26178 XR MARK M. NEWMAN, Primary Examiner MANUEL A. ANTONAKAS, Assistant Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,502,178 Dated March 2 1970 Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

' Column 1, lines 6 and 7 should read --C1aims priority,

application Great Britain, June 20, 1966, 27,508/66--.

SIGNED RND SEALED JUL 2 8 1970 am) mm 1:. sum. JR. Edwud H. mm. It Gomialioner or amt: Awaiting Officer

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