GB2179637A - Cleaning/treating internal cavities - Google Patents

Abstract

A cleaning apparatus for cleaning the interior of a compressed air bottle B comprises a pair of water-jetting lances 2A and 2B which direct high velocity water jets against the inner surface of the bottle and an actuator 1 which causes the nozzles to sweep back-and-forth around the periphery of the inner of the bottle while advancing them lengthwise of the bottle so that full coverage of the bottle interior is achieved. A mechanism for translating the reciprocating motion of a pneumatic piston into the sweeping and advancing motions of the lances is provided. Beer-kegs, mixing vats and pipelines may be similarly cleaned. <IMAGE>

Description

SPECIFICATION Apparatus for cleaning/treating internal cavities The present invention relates to apparatus for directing a highvelocityjetoffluidatthewallofan interior cavity of a workpiece, particularly but not exclusively for cleaning purposes.

Cleaning and surface treatment of interior cavities ofworkpieces pose difficulties in so far as the operative part ofthe apparatus must fit inside the cavity in question and the very act of flitting it may make it difficult if not impossible for an operator to see what is going on inside the cavity and thereby correctly operate the appartus so that the cleaning/treatment takes place evenly and effectively. Atypical example is the cleaning of gas bottles, e.g. compressed air cylinders.

The present invention is broadly concerned with the above problem and proposes providing a highvelocity jet of fluid (which may be liquid or gas although liquid is preferable for higherenergytreat- ment) in a mounting arrangement which can mount it relative to the cavity and drive itto progressively cover the wall of the cavity.Thus, according to the present invention there is provided apparatus for cleaning or other treatment of an internal cavity of a structure comprising at least one cleaning/treatment head insertable in the cavity and adapted to direct a jetofhigh velocityfluid at the cavitywall, means for mounting the head(s) relative to the cavity and an actuatorto cause translational movement ofthe head(s) lengthwise ofthe cavity and turning move mentofthe head about the axis ofthe cavity, so that the jet(s) from the head(s) can be swept pro gressively over an area ofthe cavity wall.

The actuating means may be a mechanism which translates an input motion, e.g. a linear reciprocating motion provided by a pneumatic actuator into a turning motion of the head,with intermittent orcon- tinuous indexing ofthe head along the cavity so that the jet(s) progressively coverthe interiorwall of the cavity.

Conveniently, so as not to have to provide rotary couplings in the fluid supply lines, the turning motion is a back-and-forth one, through a sufficient angle in relation to the number of heads to obtain full 3600 sweeps ofthe cavity wall; with two heads, the movement may be through, say 210 , gving 60 of overlap.

One particular area of application ofthe presentinvention is to the cleaning of bottles used for high pressure gas storage, e.g. air storage bottles for diving equipment, although it will be appreciated that there are many other applications in the cleaning field, i.e. beer- and other kegs, mixing vats, pipelines and so forth as well as other areas of application where surface treatment of an internal cavity is required.

The invention will further be described by way of non-limitative example with reference to the accompanying drawings in which Figure lisa longitudinal sectional view showing an apparatus according to the present invention installed in an air bottle B; Figure 2 is a cross-sectional view of the actuator part ofthe apparatus; Figure3isaviewon Ill-Ill in Figure 2; and Figures 4A-4Dshow the components of the probe ofthe apparatus.

Figure 1 shows an apparatus 1 embodying the present invention fitted to the neck of a vessel, compressed air diver's bottle B which it is desired to clean.

The apparatus 1 comprises two cleaning lances 2A and 2B which, as shown, are curved and have at their outer end water nozzles which direct high velocity jets of water perpendicularlyto the lengthwise axis of the bottle B. They are supplied with water (or any other suitable cleaning liquid orfluid) via hoses3A and 3B connected to a high pressure source, e.g. a pump (not shown). As shown, the outlet ends ofthe lances 2A and 28 are somewhat offset longitudinally ofthe axis of the bottle Bso that they direct water at offset areas.

In operation, the lances 2A and 2B are rotated back and forth through an arc which provides some degree of overlap between the areas swept by the jets (i.e. greater than 1800); suitably the arc is 2100. At in- tervals, the lances 2A and 2B are moved an increment of distance lengthwise of the bottle B, in the illustrated example starting at the remote, not shown, end of the bottle and proceeding leftwa rds. The combined sweeping and translational movements of the lances are driven by means of an actuatorassembly 10 which is fitted to the end E of the bottle.

The construction and operation of the actuator is most easily appreciated from Figures 2 and 3.

It will be seen from Figure 2 that the actuator 10 comprises a housing 11 which is fixed to the end E of the bottle an an internal assembly generally designated 12 which carries outthe sweeping and advancing movements ofthe lances 2A and 2B.

A rotatable collar 13 has two bores 14through which the hoses 3Aand 3B extend, this collar 13 being rotatably mounted in the end plate 15 ofthe housing 11. It is provided with a gear 16 engaged with a straight rack 17 which is driven back and forth by means of a reciprocating air piston 18 (Figure 3) of a piston and cylinderarrangement20.The rack 17is connected to the piston 18 by means of a cross-piece 19; the piston and cylinder arrangement 20 is mounted on the housing 11.

The rotating assembly 12 further includes a base plate 33 which is connected to the collar 13 and rotates back and forth with it; on the baseplate is mounted the mechanism which serves to advance the lances as they rotate.

Referring now to Figure 3, it will be seen that each of the hoses 3A and 38 is engaged by a pair of wheels 21 A, 22A and 21 B, 22B which grip the outer surface of the hoses and cause the hoses to move as the wheels rotate. The mounting 23 on which the wheels 22A, 228 are mounted is moveable on the base plate 33 by means of a screw 38, towards and away from the opposite pair of wheels so that the grip on the hoses can be adjusted.

The wheels 21,22 are caused to rotate by rotation of a shaft 24 which has on it two worm gears 25A and 25B engaged with gears 34A, 34B on the shafts on which the pairs of wheels are mounted.

Shaft 24 is, in itsturn,driven via a one way, e.g.

sprag-wheel, clutch 26 by means of a bevel gear 27 rotatably mounted on a bearing 28 on the base plate 33. The bevel gear 27 engages with a face gear 29 fixed to the inside ofthe housing 11.

What happens, therefore, is that during the stroke ofthe piston 18 in one direction, the rack 17 causes the collar 13 to rotate in one direction. The base plate 33 and bevel gear 27 are likewise caused to rotate about the central axis of the mechanism and the bevel gear 27, being engaged with the fixed ring gear 29, is caused to rotate about its own axis.So, assum ing that the direction of rotation is the one in which drive will be transmitted by the one-way clutch 26, this rotation is transferred to the shaft 24, thereby causing the wheels 21,22 to rotate and to cause the hoses 3A and 3B to be axially advanced as they un ergo a partial turning movement around the axis of the mechanism. Atthe end of the piston stroke, the rack 17 is moved in the opposite direction thus caus ing rotation of the assembly in the opposite direction. The lances are thus swept back around the wall of the bottle but, because ofthe different sense of rotation, the one-way clutch 26 does not tra nsfer drive to the shaft 24 and so the lances are notmoved lengthwise of the bottle.

Referring backto Figure 1, itwill be seen thatthe lances 2Aand 2B are connected tothe hoses3Aand 3B by means of a coupling assembly generallydes- ignated 30; this includes a collar 39 which holds the lances 2A and 2B and is slidable along a probe 31 which locates in a bush (not shown) in the end ofthe air cylinder so as to guide the lance assembly lengthwise of the bottle Band steady the lance assembly as it rotates back and forth.

Figures4A-4D show the component parts ofthe probe 31 in more detail. It comprises a high tensile, springy steel rod 32 of 1/4 inch (6.35mm) diameter, to the end 32A of which is screwed the probetip 33 which engages the inner end of the bottle to be cleaned. Once the probe rod 32 is inserted in the bottle, one or more loosely fitting, 1/2 inch (12.7mm) stainless steel spacer sleeves end of the bottle. The clamping screw 38 is used to tighten the pulleys onto the two lance hoses.

h) The cleaning cycle for the straight, cylindrical part of the bottle B isthen carried out with the actuator operating as described above.

i) The lances are replaced by a nozzle adapted for cleaning the part-spherical bottom end ofthe bottle and the lance clamp is loosened, by undoing screw 38, so there is no pulling action.

j) Finally, nozzles adapted for cleaning the partspherical top end ofthe bottle are inserted and used to clean that end.

In steps i) and j), the nozzles are onlyturned but not advanced in either direction, lengthwise in the cylinder.

Claims (16)

1. Apparatus for cleaning or othertreatment of an internal cavity of a structure comprising at least one cleaning/treatment head insertable in the cavity and adapted to direct a jet of high velocity fluid at the cavitywall, means for mounting the head(s) relative to the cavity and an actuator to cause translational movement ofthe head(s) lengthwise of the cavity and turning movement of the head aboutthe axis of the cavity, so that the jet(s) from the head(s) can be swept progressively over an area ofthe cavity wall.

2. Apparatus according to claim 1 and including a probe which, in use, extends into the cavity and serves as a guide for the cleaning/treatment head or heads.

3. Apparatus according to claim 2 and wherein the probe comprises a central rod, over which in use one or more spacer sleeves are fitted, and means are provided to place the rod in tension and the sleeve correspondingly into compression so asto rigidify the probe.

4. Apparatus according to claim 1,2,or3, wherein the actuator is adapted to turn the head(s) backandforth.

5. Apparatus according to claim 4, wherein the actuator is arranged to cause the head(s) to turn back and forth through a sufficient angle in relation to the numberand to the position(s) of thejet(s),to cause a 360" sweep of the jets around the axis of rotation.

6. Apparatus according to any one of the proceding claims wherein the actuator includes a mechanism for converting that rotational movement into an incremental movement of the head(s) lengthwise of the axis of rotation.

7. Apparatus according to claim 6, wherein the converting mechanism includes a one-way driving means.

8. Apparatus according to any one of the preceding claims, wherein the mounting means include a collar rotatable with the head(s) and having gear teeth inter-engaged with a toothed drive member.

9. Apparatus according to claim 6, wherein the toothed drive member is a straight rack connected to a piston and cylinder arrangementforcausing itto reciprocate in a manner such asto rotate the collar back and forth.

10. Apparatus according to any one of claims 1 to 9, wherein the actuator includes means for gripping the outer surface of one or more conduitsforcarry- ingfluidtothehead(s),thegripping means being rotatable and adapted such that its rotation causes movement ofthe conduit(s) lengthwise ofthe axis of rotation.

11. Apparatus according to claim 10, wherein the gripping means comprises a pair of wheels mounted for rotation about parallel axes and having peripheral surfaces contoured to grip the surface ofthe con- duit(s).

12. Apparatus according to claim 11,wherein one ofthe wheels is moveable towards and away from the other adjustably so as to accommodate variations in conduit diameter.

13. Apparatus according to claim 11 or12, wherein the pairs of wheels are caused to rotate by a shaftwhich is inter-engaged with the shafts on which they are mounted by means of corresponding gears.

14. Apparatus according to claim 6and anyone of claims 11 to 13, wherein the wheels, the one-way driving means and a bevel gear are mounted coaxi ally with one another.

15. Apparatus according to claim 14,wherein the bevel gear is engaged with a ring gear which is fixed relative to a housing of the actuatorwhereby rotation ofthe housing about its axis causes rotation ofthe bevel gear about its own axis which is perpendicular to that ofthe housing.

16. Apparatusfor cleaning/treating the innersur- face of a cavity, such apparatus being constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.