GB2207958A - Airline lubricators - Google Patents

Abstract

An airline lubricator includes a housing (2) for connection to an airline, the housing (2) mounting a deformable cartridge actuatable by the air pressure within the housing to discharge lubricant into the airline 21 to lubricate equipment powered by the airline. The housing also includes an airflow passage (38) through which air flows to the equipment. The passage (38) is adjacent to the cartridge when mounted within the housing so that deformation of the cartridge under the air pressure in the housing on depletion of the lubricant at least partly blocks the air passage (38) to at least reduce the air supply to the equipment. This gives an indication to the operator that the lubricant cartridge is depleted. <IMAGE>

Description

LUBRICATOR The present invention relates to a lubricating device, and more particularly to a lubricating device for incorporation into an airline to lubricate a pneumatically operated tool driven by the airline.

There is disclosed in Australian Patent Specification No. 540,574 a lubricant cartridge for use in an airline lubricator, comprising a tube-like body of flexible material closed at one end by a cap of more rigid material. The cartridge is mounted within the housing of the lubricator, which is connected into the airline so that the ,pressurised air flows through the housing. The cap is pierced by.

the pointed end of a discharge nozzle within the housing so that the air pressure in the housing..acts to discharge the lubricant via the nozzle into the flowing air stream to thereby lubricate a tool at an end of the airline.

It has been found that, in practice, operators of such tools do not regularly check the lubricator to ensure that there is adequate lubricant remaining within the cartridge. If this is not done, the cartridge may empty during use of the tool with the result that the tool may operate for a time without adequate lubrication thereby resulting in increased wear.

According to the invention, there is provided an airline lubricator comprising a housing for connection to an airline, said housing including means for mounting within the housing, a deformable cartridge actuated by air pressure within the housing to discharge lubricant into the airline to thereby lubricate equipment powered by the airline, said housing including an airflow passage through which air flows to the equipment, said passage being adjacent to the said cartridge when mounted within the housing such that deformation of the cartridge under the housing air pressure, upon depletion of lubricant, at least partly blocks the air passage to at least reduce the air supply to the equipment.

The deformed cartridge may either completely block air flow to the equipment in order to stop the equipment or restrict the air flow to slow the equipment. In either case, the operator will be aware that the cartridge must be replaced.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which; Figure 1 is a side elevation of the airline lubricator, the body and cap of the lubricator being shown in their separated condition in which a lubricant cartridge may be mounted within the lubricator; Figure 2 is a longitudinal section corresponding to Figure 1; Figure 3 is an end elevation of an orifice plate of the lubricator; and Figure 4 is a fragmentary longitudinal section showing a lubricant cartridge fitted to a nozzle in the orifice plate and illustrating the manner in which the cap of the cartridge is deflected on depletion of lubricant to close primary airflow passages in the orifice plate.

As shown in the drawings, an airline lubricator comprises an outer housing defined by a main cylindrical body (2) adapated to house a lubricant cartridge and a detachable cap (4), each preferably being fabricated from metal. The cap (4) includes a skirt portion (6) which fits around a collar (8) at the 'end of the body (2) and is releasably locked to the collar (8) by diametrically, opposed locking cams (10) (only one of which is shown in Figure 1) pivoted to projecting lugs, (12) on the cap (4). The cams- (10) releasably engage in a groove (14) in the collar (8) through apertures (16) in the skirt portion (6). The- cams (10) each include integral fingers (18) to permit manual engagement and release, and the fingers (18) may be locked against accidental release by removable locking pins (not shown) inserted into apertures (20) in the lugs (12).

End fittings (21) are double welded (ie welded internally and externally) to the outer ends of the body (2) and cap (4) to enable the housing to be connected to an airline so that the air flows via the housing to the tool powered by the airline.

An orifice plate (22) (Figures 2 and 3) is welded within the cap (4), the plate (22) being spaced from the end wall of the cap (4) to define therewith a mixing chamber (24). An annular washer (26) is seated against the outer periphery of the exposed face of the orifice plate (22) to provide an air-tight seal against the end of the collar (8) when the cap (4) is locked by the cams (10) to the body (2). The orifice plate (22) has a central bore which receives a nozzle (28) which is spiked at-its tail or inlet end (28a) to pierce the cap (30) (Figure. 4) of a lubricant cartridge of the type disclosed in Australian Patent Specification No. 540,574. The outlet end of the nozzle (28) lies within the-chamber (24) and receives a removable screw-threaded jet (32) which determines the effective orifice size of the nozzle (28).The jet (32) may be replaced by a different jet in order to vary the orifice size, access to the jet for this purpose being obtained via the tail end (28a) of the nozzle (28). Removal and insertion of the jet is effected through t-he -tail end.

(28a), of the nozzle- (28) to prevent.. accidental loosening and ejection of the jet under the influence of the air stream.

The nozzle (28) includes a shoulder (34) against which sits an annular flange (35) projecting from the cap (30) of the cartridge and which surrounds a zone of reduced thickness which is pierced by the tail end (28a) of the nozzle (28), the cap (30) thereby being spaced from the surface of the orifice plate (22). In the annular zone immediately surrounding the nozzle (28), the plate (22) includes a series of apertures (38), which constitutes large area primary airflow passages between the body (2) and the mixing chamber (24) within the cap (4).

Surrounding the apertures (38), the plate (22) includes a continuous annular land (40), the outer diameter of which is slightly larger than the outer diameter of the cap (30) of the cartridge. Externally of the land (40), the plate (22) includes a number (for example two) of small area secondary airflow passages (42). All or some of these passages (42) may be optionally closed by removable plugs (44) for reasons which will be described shortly. The plugs (44) are inserted into the passages (42) from the inlet side so as to prevent accidental ejection into the mixing chamber (24) and thence into the pipeline.

The lubricator is connected within the airline by suitable couplings which engage the end fittings (21) so that compressed air enters the housing at the end of the body (2) and is-discharged at the end of the cap (4). The air pressure within the body (2) and which may be 70 p.s-i. or more, causes lubricant to be expelled from - the flexible body of the cartridge via the nozzle .(28) into the mixing chamber (24) where it mixes with the air stream passing into the chamber (24) from the body (2) via the primary airflow passages (38), the air entering these passages by flowing between the cap (30) of the cartridge and the orifice plate (22).

The body of the cartridge is of a flexible material which progressively collapses under the surrounding pressure as the lubricant is expelled.

When the lubricant is filly depleted, the cartridge body will have collapsed completely against the inside of the cap (30). The air pressure then acting substantially directly against the inside face of the cap (30), causes the cap to deflect towards the orifice plate (22) whereby the outer peripheral portion of the cap (30) engages the annular land (40) (as shown in dotted lines in Figure 4) and thereby prevents passage of the primary air into the passages (38). The primary air flow to the tool is thereby blocked and the tool will stop thus indicating to the operator that the lubricant cartridge is depleted and must be changed to resume operation.

Complete stoppage as discussed above, occurs if all of the secondary passages (42) sure closed by the plugs (44). Some operators of pneumatic equipment merely require that a signal is given on depletion of the lubricant, rather than complete stoppage. To suit the needs of such operators, one or more-of-the plugs (44) are removed to open the corresponding secondary passage (42). With one or more of the secondary passages open, blockage of the primary passages (38) upon depletion of the lubricant will not result in complete blockage of the air flow to--the tool.

Instead, a restricted air flow will occur via the secondary passage(s) thereby slowing the tool to indicate lubricant depletion to the operator. The reduced speed of operation will also reduce damage and/or wear of the tool from inadequate lubrication.

To provide for greater flexibility of adjustment, the plug (44) may be solid so as to completely block the passage (42) or may be bored as shown at (45) to provide for restricted airflow. An operator thus has a choice of operating with both passages (42) unblocked or with one or both passages blocked and/or partially blocked depending on the type of plug (44) used.

Upon blockage of the primary airflow passages, the housing of the lubricator will need to withstand the substantial airline pressure which will build up within the housing. The fabrication of the housing from metal, the positive locking of the cap to the body and the double welded mounting of the end fittings ensures that the coupling has inherent strength and safety features for this purpose.

The embodiment has been described by way-of example and modifications are possible within the scope of the invention.

Claims (10)

Claims

1 An airline lubricator comprising a housing for connection to an airline, said housing including means for mounting within the housing, a deformable cartridge actuated by air pressure within the housing to discharge lubricant into the airline to thereby, lubricate equipment powered by the airline, said housing including an airflow passage through which air flows to the equipment, said passage being adjacent to the said cartridge when mounted within the housing such that deformation of the cartridge under the housing air pressure, upon depletion of lubricant, at least partly blocks the air passage to at least reduce the air supply to the equipment.

2. An airline lubricator according to claim I wherein the mounting means comprises a lubricant discharge assembly operative to engage a cap at an end of the cartridge whereby lubricant passes into said discharge assembly via the cap, and the airflow passage lies adjacent the discharge assembly so as to be at least partly blocked by deformation of the cap upon depletion of lubricant.

3. An airline lubricator according to claim 2, wherein the mounting means is adapted to engage a central portion of the cap with an outer peripheral portion of the cap being normally unsupported, the housing further comprising a zone adapted to face towards the outer peripheral portion of the cap, the zone being in close proximity to the outer peripheral portion of the cap, but normally being spaced therefrom, and at least a substantial part of the airflow passage being bounded externally by the zone such that air can norm, ally flow between the outer peripheral portion of the cap and the zone to the passage, the cap deforming upon depletion of the lubricant'by movement of the outer peripheral portion of the cap towards the zone whereby to at least substantially block the airflow to the passage.

4. An airline lubricator according to claim 3, wherein the zone is annular and surrounds the mounting . means and the passage comprises an array of openings between the mounting means and the zone.

5. An airline lubricator according to claim 3 or claim 4, wherein a minor part of the passage is externally of the zone whereby said minor part of the passage can remain open to provide restricted airflow after deformation of the cap to close the substantial part of the passage.

6. An airline lubricator according to claim 5, further comprising means for selectively blocking the minor part of the passage.

7. An airline lubricator according to claim 6, wherein the minor part of the passage is defined by a plurality of openings externally of the zone, and the blocking means comprises a respective plug for separately blocking each of the openings.

8. An airline lubricator according to claim 7, wherein the plugs include plugs for completely blocking the openings and plugs for partly blocking the openings.

9. An airline lubricator according to claim 5, wherein the lubricant discharge assembly comprises a spike adapted to pierce the central portion of the cap, the spike being carried by means of plate mounted in the housing, the said zone being defined on the plate, and the substantial and minor parts af the airflow opening being formed through the plate.

10. An airline lubricator substantially as hereinbefore described with reference to the accompanying drawings.