US3410529A

US3410529A - Tunable acoustic fluid mixer having easy access to internal working parts

Info

Publication number: US3410529A
Application number: US645285A
Authority: US
Inventors: Sergio G Simonetti
Original assignee: Sonic Engineering Corp
Current assignee: Sonic Engineering Corp
Priority date: 1967-06-12
Filing date: 1967-06-12
Publication date: 1968-11-12
Anticipated expiration: 1985-11-12
Also published as: FR1569230A; GB1173125A

Description

Nov. 12, 1968 5. cs. SIMONETTI 3,410,529

TUNABLE ACOUSTIC FLUID MIXER HAVING EASY ACCESS TO INTERNAL WORKING PARTS Filed June 12, 1967 2 Sheets-Sheet 1 INVENTOR. 5596/0 G, 57MON7TI Nov. 12, 1968 s. s. SIMONETTI 3,410,529

TUNABLE ACOUSTIC FLUID MIXER HAVING EASY ACCESS TO INTERNAL WORKING PARTS 2 Sheets-Sheet 2 Filed June 12, 1967 United States Patent Ofice 3,410,529 Patented Nov. 12, 1968 ABSTRACT OF THE DISCLOSURE A fluid mixer of the type including a fluid orifice for forming a jet which impinges upon a blade to cause oscillation of the blade and thorough mixing of the fluid and any substances carried thereby as a result of cavitation and other effects produced by the vibrating blade, and an adjustable valve downstream of the blade for varying the back pressure upstream thereof; wherein one or more of the blade assembly, the valve assembly, and the jetforming orifice assembly, may be removed from the fluid mixer through respective slots therein, which slots are exposable by the retraction of exterior sleeves so that the fluid mixer need not be removed from the line to gain such access; also wherein the valve assembly comprises a conical seat member and a conical valve member, with the valve member spring loaded for slight unseating movement under upstream overpressures; also wherein the axial positions of the blade assembly and of the valve member are individually adjustable by individual micrometer movements operable to move the aforesaid sleeves which are connected respectively to said blade assembly and said valve member but which are disconnectable therefrom for the aforesaid axial retraction to expose said individual slots for removal of said blade assembly and valve member; and wherein the two micrometer movements respectively controlling the axial position of the blade assembly and of the valve member are supplied with indicia and locking so that any axial setting of the blade assembly and/ or the valve member is precisely repeatable and one set is maintainable.

Background of the invention The principle of mixing fluids and fluid carried substances by the vibration of a blade excited by a jet of the fluid is described in the Cottell US. Reissue Patent 25,324, issued Jan. 29, 1963, and also in the Jones US. Patent 3,169,013, issued Feb. 9, 1965. In the Cottell US. Patent 3,176,964, issued Apr. 6, 1965, there is taught the adjustment of the axial position of the blade with respect to the jet-forming orifice, and also the adjustment of the back pressure by means of a downstream throttling valve.

In all of these devices, and even in the last-mentioned Cottell patent, there persist a number of disadvantages, although the basic principles of this class of mixer are very superior. Specifically, different liquids having different specific gravity and viscosity and other fluid characteristics are optimally mixed with different blade to jetforming orifice distances and difiFerent back pressures. Heretofore, changing liquids, or changing the substances carried by a given liquid, has required that the fluid mixer be shut down so that the internal parts could be adjusted, or at best, as in the last-mentioned Cottell device, previous devices have provided only a rough form of external adjustment. Even where external adjustment has been possible, it has not been reproducible, and when switching between various forms of liquid is practiced, it has not been possible to reset the previous setting without experimentation to again find the optimum settings for that liquid.

Moreover, in all of the prior art devices the internal working parts require inspection and/ or replacement from time to time, especially when abrasive or other deleterious substances are carried in the liquid. Until the present invention, this has required a complete breakdown of the mixer to remove the internal parts, necessitating removal from the fluid line in which the mixer is interposed. As will be understood, this is a processing inconvenience both in terms of the amount of labor required and in terms of the inconvenience.

Summary 0 the invention A fluid mixer including a jet-forming orifice assembly, a blade assembly, and a downstream valve assembly, all axially mounted, wherein the blade assembly and the valve portion of the tuning valve assembly are mounted through respective lateral slots in the mixer casing to respective internal sleeves carried thereon, and the respective sleeves are movable by separate micrometer movements, so that adjustment of the axial positions of the blade assembly and the valve portion are precisely and repeatably adjustable and lockable by means of the micrometer movements, and also so that disassembly of the respective external sleeves from the micrometer movements and the respective blade assembly or valve portion allows axial retraction of the sleeves to expose the slots through which the blade assembly and valve portion may be individually removed. In the illustrated embodiment a separate sleeve is provided covering slots through which the jet-forming orifice assembly is removable. With the invention, the proper setting for any previously employed fluid can be attained and maintained by adjusting and locking the micrometer movements, and at the same time the internal working parts can be removed with very little effort and even without removing the mixer from the line in which it is interposed.

In the figures:

FIG. 1 is a perspective view of a presently preferred but merely illustrative embodiment of the invention;

FIG. 2 is an enlarged end elevation view of the apparatus shown in FIG. 1;

FIG. 3 is a section view of the apparatus shown in FIG. 2 taken along plane 3-3 therein and showing internal details of construction and assembly;

FIG. 4 is an enlarged detail section view of a portion of the apparatus shown in FIG. 3 taken along plane 44 therein; and

FIG. 5 is an enlarged detail section view of a portion of the apparatus shown in FIG. 3 and taken along plane 55 therein.

Referring now to the figures, there is shown an illustrative embodiment of an improved form of fluid mixer indicated generally at 10, operating upon acoustic principles (i.e., the liquid whistle type), having adjustable controls able to tune the mixing for maximum efficiency, and being arranged so that the working internal parts thereof are readily accessible even while the mixer remains connected at upstream and downstream ends thereof.

Viewed externally, as in FIGS. 1 and 2, the mixer 10 includes a support base 11 having a pair of upright support columns 11a, 1111. An elongated housing indicated generally at 20 extends from an upstream inlet orifice indicated generally at 20:: to a downstream outlet orifice indicated generally at 20b, and includes an enlarged centrally located mounting and control portion indicated generally at 30. Mounting and control portion 30 includes a support collar 35 having connected upper and lower halves 35a, 35b mounted for slidable engagement upon support columns 11a, 11b, a micrometer adjustment means indicated generally at 40 (FIG. 2) nearer outlet orifice b, and a micrometer adjustment means indicated generally at 50 nearer inlet orifice 20a (FIG. 1).

It is a feature of the invention associated with the housing configuration, as distinct from the internal working parts, that the entire elongated housing 20 can be raised and lowered upon support columns 11a, 11b in order to make appropriate line connections at inlet and outlet orifices 20a, 20b. For that purpose, a pair of flats 11c, 11d (FIG. 2) are provided respectively on columns 11a, 1117. A pair of set screws a, 30b (FIG. 2) are provided in lower part b of support collar 35 so as to bear upon flats 11c, 11d respectively, thereby locking the elongated housing 20 in place vertically upon columns 11a, 11b. A pair of collars 11e, 111 are carried axially on columns 11a, 11b, under mounting and control portion 30, and set screws 11g, 1112 respectively are provided therein to bear upon flats 11c, 11d, thereby affording auxiliary means for locking the elongated housing 20 in place vertically on columns 11a, 11b. In addition to providing vertical adjustment for purposes of installation, the support base 11 bears the weight of the entire elongated housing 20 thereby sparing the inlet and outlet fluid lines (not shown) between which the mixer 10 is interposed, from a weight which they may not themselves be capable of supporting. A plurality of mounting apertures 11i (FIG. 1) are provided for bolting the support base 11 to its supporting surface, if desired.

As will appear hereinbelow, it is another feature of the invention associated with the housing configuration, that a complete removal of the internal working parts can be effected without disconnecting the orifices 20a, 20b, from the respective inlet and outlet lines (not shown) to which they are secured. Such removal of internal working parts is desirable periodically for the purpose of cleaning, inspecting, or replacement thereof, and obviation of the necessity for disconnection of the mixer from the fluid lines simplifies the procedure appreciably.

This last feature, and additional features arising from the details of construction, both of the housing and the internal Working parts, including their form, arrangement, and mode of operation, will be best understood by recourse to FIGS. 3-5 inclusive, during the following detailed description thereof. The aforesaid additional features will be mentioned throughout as sufficient description of their associated parts is set forth.

Referring now to FIGS. 3-5, the elongated housing indicated generally at 20 includes an upstream housing portion 21, and a downstream housing portion 22, both being generally tubular in configuration. Connected to the upstream end of housing portion 21 is an adaptor 26, generally tubular, including inlet orifice 20a, and provided with threads for connection to an inlet line (not shown). Similarly, connected to the downstream end of housing portion 22 is an adaptor 27, including outlet orifice 20b, for connection to an outlet line (not shown). Usually the

adaptors

26, 27 are identical, as illustrated, but they can be different, as the need arises.

Housing portion 21 includes a first annular flange 21a located within the mounting and control portion indicated generally at 30, and a second annular flange 21b, also located within portion 30, spaced from flange 21a, and terminating tubular member 21. Correspondingly, housing portion 22 has a single annular flange 22a, located terminally thereon within portion 30. The flanges 21b, 22a respectively of

housing portions

21, 22 are in axial contact within mounting and control portion 30, somewhat offset from the center thereof So as to be located closer to micrometer adjustment means rather than 50. A peripherally spaced plurality of screws (FIG. 3) axially connect the

housing portions

21, 22 at the mating flanges 21b, 2211.

Housing portions

21, 22 each include, at their respective ends adjacent flanges 21b, 22a, an annular recess 210, 220, which cooperate when the flanges 21b, 22a are in axial contact, to define a single annular recess. Closely held within that single annular recess 21c, 220 is a tuning valve seat member 23 of generally cylindrical outline and having a pair of conical bores 23a, 23b, each diminishing in diameter toward the center of tuning valve seat 23 where they meet, so that seat member 23 is symmetrical and can be reversed within the annular recess 21c, 220. In the illustrated orientation of seat member 23, the surface of conical bore 23b, being oriented downstream, is the actual seat surface. A pair of

annular grooves

23c, 23d are provided in the outer cylindrical surface of seat member 23 respectively adjacent the annular recess portions 21c and 220. Within each of

annular grooves

23c, 23d is carried an O-ring 23a for sealing of the respective interfaces between tuning valve seat member 23 and annular recess portions 21c and 220. As will appear more fully hereinbelow, access to, and removal or replacement of, tuning valve seat member 23 is accomplished by parting the

housing portions

21, 22 at their flanges 21b, 22a after removal of screws 60.

Flange 22a of housing portion 22, and flange 21a of housing portion 21, each includes an annular stepped portion 22am, 21aa respectively, in each instance facing away from the main body portion of the associated housing portion, i.e., toward the center of mounting and control portion 30. The micrometer adjustment means indicated generally at 40 is mounted for rotation on flange 22a, and the micrometer adjustment means indicated generally at 50 is mounted for rotation on flange 21a. The parts are identical as between means 40 and 50, and detailed description will be made with respect to means 40.

Micrometer adjustment means 40 includes an annular micrometer thimble 41, an annular retaining ring 42, and an annular calibrator ring 46. Thimble 41 is located on the side of flange 22a adjacent the main body portion of housing portion 22, and includes a main body portion 41a having a surface 41b bearing axially against flange 22a, and a tab portion 410 having a surface 41d bearing radially against flange 22a. Tab portion 410 extends across the top of flange 22a into flush registration with the surface of stepped portion 22aa. Micrometer retaining ring 42 bears against the aforesaid flush surfaces of stepped portion 22aa and tab portion 410, and is of suflicient thickness so that, when in place as illustrated, the surface thereof remote from micrometer thimble 41 lies flush with the interface between flanges 21b, 22a. A plurality of screws 42a are countersunk through retaining ring 42 and into the tab portion 410 of micrometer thimble 41 in order to capture thimble 41 axially on flange 22a for rotation thereon. The surface 41b of micrometer thimble 41 is provided with an annular groove and O-ring 41], while the retaining ring 42 is provided with an annular groove and O-ring 42b, for sealing of the corresponding interfaces. Micrometer thimble 41 is provided with four micrometer handles 41g which are secured by screw threads into tapped apertures in the main portion 41a of the micrometer thimble 41. The radially inward surface 41i of the main body 41a of micrometer thimble 41 is spaced from and parallel to the housing portion 22 and is provided with screw threads therealong. The orientation of calibration ring 46 to thimble 41 will be described after description of a tuning valve sleeve 70, which is engaged with and moved axially by thimble 41.

Tuning valve sleeve 70 extends from flange 22a along a portion of tubular member 22, and has an inner diameter such as to allow close sliding contact therewith. Unlike the parts of micrometer adjustment means 40 and 50 themselves, sleeve 70 varies somewhat from the corresponding sleeve (to be described) mated with means 50, although they are very similar. The main portion of tuning valve sleeve 70 is of a thickness sufficient to provide clearance with the threaded surface 411' of micrometer thimble 41, but an L-shaped portion 70:: thereof most adjacent to flange 22a is of greater thickness, and is threaded, so as to threadedly engage with the threaded surface 411 of micrometer thimble 41.

Tuning valve calibrator ring 46 has annular stepped surfaces radially and axially mated with micrometer thimble 41, and has an inwardly extending annular portion 46a which touches the main outer surface of tuning valve sleeve 70. An inclined surface 46b thereof is provided (FIG. 2) with radial index markings 460 which cooperate with markings on tuning valve sleeve 70 to yield micrometer readings in known fashion. While the markings on sleeve 70 cannot be seen in the drawings, they are identical to those on the other sleeve, to be described below, associated with thimble 50, and visible in FIG. 1. The inwardly extending portion 46a of calibration ring 46 is provided with an annular groove and O-ring 46d at the contacting surface with sleeve 70, and the housing portion 22 is provided with a pair of annular grooves 22d along the portion thereof underlying sleeve 70 and having O-rings 22e carried therein, for sealing of the respective contacting surfaces.

It will be understood that micrometer thimble 41, being carried for rotation upon flange 22a as aforesaid, can be rotated thereon by manipulation of handles 41g. Rotation of micrometer thimble 41 causes, within the limits of travel determined by flange 22a and inwardly extending portion 46a of calibration ring 46, axial movement of tuning valve sleeve 70 along housing portion 22 by virtue of the threaded engagement therebetween. The sleeve 70 is prevented from rotation with the micrometer thimble 31 by means presently to be described in connection with other functions.

As previously mentioned, the parts of micrometer adjustment means 50 are identical to those already described with reference to micrometer adjustment means 40. Briefly, means 50 includes a micrometer thimble 51 mounted for rotation on flange 21a, a micrometer retaining ring 52, and a calibrator ring 56. Screws 52a connect retaining ring 52 to thimble 51, and set screws 56f connect calibrator ring 56 to thimble 51, so that ring 52 and ring 56 rotate with thimble 51. Four handles 51g are threadedly mounted in thimble 51. A blade adjustment sleeve 72 is carried upon tubular member 21 in the same manner as has already been described with reference to tuning valve sleeve 70, and is threadedly engaged with micrometer thimble 51 for the same purpose, i.e., axial movement of sleeve 72 on housing portion 21. Calibrator ring 56 also includes markings 560 (FIG. 1) and, as with means 40, these cooperate with markings on the associated sleeve to calibrate the adjustment thereof. These latter markings are shown at 56d in FIG. 1. The arrangement of O-rings between both the thimble 51 and retaining ring 52 with flange 21a, and between both the housing portion 21 and the blade calibration ring 56, is the same as has already been described with reference to the corresponding parts of micrometer adjustment means 40. The only functional difference between the various parts associated with micrometer adjustment means 50 and sleeve 72 on the other hand, resides in a shortened axial length of blade adjusting sleeve 72 as compared to tuning valve sleeve 70. The purpose and extent of this shortening will be presently described with reference to internal features of the apparatus.

Housing portion 22 includes a pair of opposed longitudinal slots 22n (FIG. 3). A valve member indicated generally at 80 (FIG. 5) is carried within slots 22m. Valve member 80 comprises a body portion 81 which extends laterally into slots 22m. A pair of shoulder screws 62 pass through tuning valve sleeve 70 and are threadedly engaged within valve body 81 so that valve body 81 is moved axially within tubular member 22 with axial movement of tuning valve sleeve 70. A valve stem 82 is carried within a bore 81a within valve body 81 and is smaller in radius thereby providing an annular gap therebetween. A head 82a is provided at the downstream end of valve stem 82,

a stepped shoulder 82b is provided at a centrally located portion, and an annular groove 82c is provided at the upstream end of stem 82. A valve piston 83 has a conical working surface 83a adapted to mate with (FIGS. 3 and 5) the conical bore 23b of tuning valve seat 23. Valve piston 83 includes a central bore 83b mated with valve stem 82, and the downstream extreme of piston 83 abuts shoulder 82b. A set screw 830 is provided in piston 83 for engagement with annular groove 820 in valve stem 82 to removably mate piston 83 and stem 82. A compression spring 84 is carried coaxial with valve stem 82 within the bore 81a of valve body 81, with one end thereof bearing against piston 83, and the other end thereof bearing against the remote portion of body 81, thereby bottoming head 82:: against body 81. The maximum height of valve member is no greater than the height of slots 22m, 22n and the maximum axial length of valve member 80 is no greater than the axial length of slots 22m, 2211.

As has already been explained, movement of tuning valve sleeve 70 by micrometer thimble 41 within the axial limits permitted by flange 22a and ring portion 46a, will move valve body 81 therewith within equal axial limits because of the positive connection therebetween at screws 62. The conical working surface 83a of piston 83 is thereby axially moved toward and away from the valve seat 23. In FIGS. 3 and 5 the sleeve 70 is shown at one axial extreme of its movement, in axial contact with flange 22a, corresponding to the closed position of the tuning valve parts 80, 23 as illustrated. When the valve is totally closed as illustrated, the entire apparatus 10 is prevented from developing internal over-pressures upstream of the valve which could damage the upstream pumping system, by the check-valve effect inherent in the ability of piston 83 to move in the unseating direction against spring 84. The spring rate of spring 84 is chosen to be sufliciently great so as to provide this check valve feature when the piston 83 is in the fully closed position, but to permit essentially no piston movement when the piston 83 is in any degree of open orientation with respect to seat 23. When the micrometer thimble 41 is turned so that sleeve 70 is moved, the valve piston 83 is moved correspondingly away from the valve seat 23, thereby proportionately reducing the back pressure developed in the chamber 120 between the upstream side of valve seat 23 and the downstream side of jet forming fixture 100. As will presently be explained, this adjustment of the position of valve piston 83 with respect to valve seat 23 acts to tune the operation of the apparatus 10 by adjusting the pressure in chamber 120.

It is an important feature of the invention that valve member 80 can be removed for cleaning or replacement or the like without removing the apparatus 10 from upstream and downstream connections in the line in which it is interposed. This can be accomplished as follows. The bolts 62 are first removed so as to free valve body 81 within slots 22m, 2211. The set screws 46 in tuning valve calibrator ring 46 are next removed, and the ring 46 can then be moved axially completely out of the way toward the remote end of housing portion 22. This latter step removes the restraint upon sleeve 70 represented by portion 46a of ring 46, and accordingly the micrometer thimble 41 can then be turned to advance the sleeve 70 away from flange 22a axially until there is no further threaded engagement, upon which the sleeve 70 can manually be further removed axially out of the way toward the portion of housing portion 22 adjacent orifice 20b. This latter step exposes the slots 22m, 22n in housing portion 22. The valve member 80 can then be moved axially into congruence with the slots 22m and removed laterally out of either of the slots.

Housing portion 21 includes a pair of opposed longitudinal slots 21m, 2111 (FIGS. 3 and 4). A blade assembly indicated generally at (FIG. 3) is carried within slots 21m, 2112 (FIG. 4). Blade assembly 90 comprises a blade 91 having a knife-edge end 91a, a support end 911) and an intermediate shoulder 91c. A blade holder 92 extends laterally (FIG. 4) into slots 21m, 2111. Blade holder 92 includes a centrally located depressed portion in the upper surface thereof indicated at 92:: in FIG. 4, extending downwardly slightly more than half the depth of blade holder 92, and having a lateral width slightly greater than the lateral width of blade support portion 91b of blade '91. Blade support portion 91b is nested within depressed portion 92a, and a blade block 93 overlies blade support portion 91b within depressed portion 92a. Blade block 93 covers the entire blade support portion 91b and extends laterally fully within depressed portion 92a of blade holder 92.

The height of blade support portion 9112 together with the height of blade block 93 is suflicient to fill in depressed portion 92a of blade holder 92 completely, so that a uniform height of blade assembly 90 is presented. As can be seen in FIGS. 3 and 4, this height of blade assembly '90, which is the maximum height thereof, is such as to constitute a sliding fit within the height of slots 21m, 2111. Also, the length of blade assembly 90 from blade edge 91a to the remote portion of blade assembly 90 is smaller than the length of slots 21m, 2112. A pair of shoulder screws 63 pass through blade adjustment sleeve 72 and are threadedly engaged within the lateral portions of blade holder 92 so that the blade assembly 90 is moved axially within housing portion 21 with axial movement of blade adjustment sleeve 72. Screws 63 are sealed by O-rings 63a at flats under their heads.

Housing portion 21 also includes a pair of opposed slots 21p, 21q (FIG. 4) located upstream of

slots

21m, 21n, i.e., further toward orifice 20a. The downstream extreme of slots 21p, 21q is spaced slightly upstream from knife-edge 91a of blade assembly 90 when blade assembly 90 is in the extreme upstream position shown in FIGS. 3 and 4. Unlike

slots

22m and 21m, 21n, which are relatively shallow in height and relatively long axially, slots 21p, 21q are relatively short axially and relatively great in height. Thus, slots 21p, Zlq do not present a longitudinal configuration along the opposed sides of housing portion 21, but rather present a partial circumferential configuration in the opposed sides of housing portion 21. That is to say, slots 21p, 21q occupy major portions of the annulus of housing portion 21 thereat, their mutual upper portions being spaced, and their mutual lower portions being spaced, to leave stock remaining at the upper and lower extremes of housing portion 21 thereat as may be seen in FIG. 3.

As may be seen in FIG. 4, a lateral shoulder 21p is provided by the housing portion 21 at the downstream extreme of slot 21p, and a corresponding lateral shoulder 21g is provided by the housing portion 21 at the downstream extreme of slot 21q. The bore diameter within housing portion 21 immediately adjacent to slots 21p, 21q on the downstream side thereof, is slightly less than the height of slots 21p, 21q. Thus, as may be seen in FIG. 3, shoulder portions are formed between the bore 95 and the upper and lower portions 21p" of slot 21p. These shoulder portions of course continue across the upper and lower portions of housing portion 21 between slots 21p, 21: and have been designated as shoulders 2111" only for convenience, since they are the mutual continuation of both lateral shoulders 21p, 21q, across the upper and lower portions thereof. The lateral shoulders 21p, 21q thus extend, in narrowed form, across the upper and lower portions of housing portion 21 at portions 21 2", thereby providing in effect a complete annular shoulder.

A jet forming fixture 100 is carried partially within bore 95 and partially within slots 21p, 21q as may be best seen in FIG. 3. With reference to FIG. 4, it will be seen that a downstream portion th: has a cylindrical outer configuration which fits closely within bore 95', and a pair of laterally extending tabs 1001; (FIG. 4) which extend respectively into the downstream portions of slots 21p, 21q. The tabs 16Gb have a vertical dimension sufficient so that they fit closely within the vertical dimension of slots 21p, 21: and thereby abut upper and lower shoulder portions 21p' (FIG. 3). Jet forming fixture 100 is thereby retained axially upon lateral shoulders 21p, 21q' around the aforesaid complete annular periphery thereof, including at the upper and lower shoulder portions 21p shown in FIG. 3, against fluid pressure exerted from upstream thereof. Fixture 190 is sealed by O-ring 100x. A retaining ring 110 is carried within

slots

21p, 21g, and has a vertical dimension (FIG. 3) equal to the height of slots 21p, 21q and a horizontal diameter (FIG. 4) equal to the outer diameter of housing portion 21 so that the slots 21p, 21: are fully occupied (these lateral portions of ring 110 are partially broken away in FIG. 4 to show the slots 21p, 21(1). The longitudinal dimension of retaining ring 110 is suflicient to form a close fit longitudinally within slots 21 21q with the portions 10Gb of jet forming fixture 100.

The internal bore of retaining ring 110 is of the same diameter as the internal bore of housing member 21 immediately upstream thereof. Jet forming fixture 100 in cludes a chamber 100d having an upstream opening of the same diameter as the internal bore of retaining ring 110, and a downstream lateral slit opening 100e in a domed wall 100i. Slit 1006 is directly in line with blade edge 91a of blade assembly 90, so that when fluid is pumped through orifice 20a and into chamber 100d under pressure, a high pressure fluid jet is formed on the downstream side of slit opening 100e and impinges directly upon blade edge 91a.

As can clearly be seen in FIGS. 3 and 4, blade adjustment sleeve 72 is shortened, as aforesaid, as compared to tuning valve sleeve 70. Specifically, blade adjustment sleeve 72 is sufliciently short so that the upstream end thereof lies axially in the vicinity of jet forming fixture 100 when sleeve 72 has been axially advanced to its upstream limit by micrometer thimble 51 (i.e., until it is stopped by calibrator ring 56) as is illustrated in FIGS. 3 and 4. The exact position of the upstream end of blade adjustment sleeve 72 when at its upstream extreme is not otherwise critical, except that it should not extend to the longitudinal position occupied by the downstream extreme of

slots

21p, 21c for disassembly reasons that will appear presently. A short sleeve 28 is carried on housing portion 21 overlying slots 21p, 21q and, when blade adjustment sleeve 72 is at the limit of its upstream movement, is in abutment therewith. Sleeve 28 has the same inner and outer diameter dimensions as sleeve 72, and is axially secured in position on housing portion 21 by a pair of set screws 28a, 28b.

It will be understood that, in the manner already described with reference to the adjustment of the axial position of valve body by micrometer adjustment means 40, the axial position of blade assembly 9%) is accomplished by micrometer adjustment means 59. Briefly, movement of thmble 51 at handles 51g moves sleeve 72 in the axial directions, thereby causing blade edge 91a to move with assembly closer to or further from orifice 1002 within the same axial limits as are set upon sleeve 72 itself by ring 56 and flange 2.1a.

It is another important feature of the invention that either or both of blade assembly 90 and jet forming fixture can be removed for cleaning or replacement or the like without removing the apparatus 10 from upstream and downstream connections in the line in which it is interposed. This can be accomplished as follows. The set screws 28a are loosened, allowing sleeve 28 to be moved axially upstream over adaptor 26, thus exposing

slots

21p, 21g. If it is desired to remove jet forming fixture 180, this is accomplished by first sliding ring out of either of slots 21p, 21q, and then moving fixture 100 axially upstream into full congruence with slots 21p, 21q, and sliding it out of either of slots 21p, 21:

If it is desired to remove only blade assembly 90 and not jet forming fixture 190, the sleeve 28 will be loosened and moved axially upstream as aforesaid, but the ring 110 and fixture 100 will be left in place. If it is desired to remove both jet forming fixture 100 and blade assembly 90, the foregoing removal will be practiced first. In either of these instances, the next step involves removal of blade assembly 90. This is accomplished in the same manner as has already been described with reference to valve member 80. Briefly, set screws 56 are loosened, allowing calibrator ring 56 to be moved axially upstream out of the way, thereby removing the upstream stops on the movement of blade adjustment sleeve 72. The sleeve 72 is then unthreaded from thimble 51, and axially moved upstream cut of the way, thus exposing slots 21m, 2111. Blade assembly W is then moved downstream until fully congruent with slots 21m, 2112, and is removed laterally through either of them.

From what has already been said, it will be appreciated that, without removing the mixer from the line in which it is interposed, three of the four sensitive working internal parts can be removed, i.e., the valve body 80, the blade assembly 90, and the jet forming fixture 100. In order to remove the tuning valve seat member however, removal from the lines must be practiced. Thus, bolts (not shown) are countersunk into bolt holes on either side of the upper edge of upper support collar portion 35a, one of which may be seen at 35c in FIG. 1, to engage the upper and lower portions 35a, 35b. To remove seat member 23, these bolts are first removed, and then the set screws a, 30b and 11g, 1111 are loosened, to move the portion a upwardly and the portion 35b downwardly, thereby eXpOsing the bolts (FIG. 3). Bolts 60 are then removed, so that

housing portions

21, 22 can be moved apart axially to yield the seat member 23.

In general, the jet forming fixture 100 and the seat member 23 do not frequently need cleaning, and almost never need replacement because neither undergoes any significant wear. However, the blade assembly 90, and especially the valve member 80 with its internal parts, can require frequent cleaning or replacement, especially when hostile fluids are carried by mixer 14 In addition to the ease of access to the sensitive internal parts, especially without necessity for complete breakdown of all the mixer 10 parts to get at them, and even without taking the mixer 10 out of the line, the mixer 19 according to the invention has very superior mixing and control of mixing characteristics. Indeed the combination of these attributes, i.e., ease of access to working parts together with excellent control of excellent mixing characteristics, is itself .a feature of the invention.

Mixing, of course, as is taught in the prior art, occurs because of the vibration of blade tip 91a in the high pressure jet formed from orifice 100e, causing cavitation phenomena. It is desirable to vary the orifice 1002 to blade tip 910 distance to maximize this phenomena with a given fluid and upstream fluid pressure. The manipulation of micrometer adjustment means 50 accomplishes this variation of orifice to blade tip distance. Similarly, it is desirable to vary the ambient pressure at blade tip 91a to affect the'cavitation phenomena. This occurs with the present invention because of varied back-pressure supplied by valve 23, 80 downstream of tip 91a. Thus, adjustment of micrometer means 40 adjusts the distance between valve member 80 and seat member 23, thereby adjusting the ambient pressure at blade tip 91a and tuning the mixing.

In operation, the mixer 10 is placed in a line by attachment to

adaptors

26, 27, and the fluid flow is commenced. An acoustic pickup 130 (FIG. 3) monitors the acoustic energy present at a point immediately upstream of valve seat member 23. Pickup 130 is attached to an acoustic meter (not shown) which indicates acoustic intensity. The micrometer adjustment means 51 is then adjusted until the orifice 100e to blade tip 91a distance produces maximum acoustic intensity as indicated by the meter. This will of course vary with the fluid in question,

what if any load of solid particulate or liquid material it is carrying, etc. Once set, the micrometer 51 reading (on indices 56d and 560, FIG. 1) may be recorded, and a set screw 51x is tightened to lock thimble 51 in place on flange 21a so that the correct setting will be maintained.

Then the micrometer adjustment means 40 will be manipulated until the valve 80, 23 is tuned to the maximum cavitation effect as recorded on the acoustic meter (not shown) attached to pick-off 130. Again, this will vary with the liquid in question, and operating conditions. Readjustment of micrometer adjustment means 50 may then be necessary, and another, finer adjustment of micrometer adjustment means 40. In any event, when the final adjustment of means 50 is made, the micrometer reading is taken and recorded as with means 40, and a set screw 41x is engaged to lock thimble 41 in place on flange 22a thus maintaining the correct setting.

Thus, it is yet another feature of the invention that fine adjustments of the blade tip 91a to orifice little distance, and the back pressure valve can be made; that because of the micrometer aspect thereof they are fully reproducible; and that they can be locked in place by screws 51x,

1x so that the mixer can maintain its setting during operation.

Also, as has already been indicated, since the mixer 10 requires a pressure head at the upstream inlet up to 800 psi, which often is applied by a positive displacement pump, it is a safety feature of the invention that full blockage is afforded by valve 80, 23 when seated as illustrated, but that under pressure overload this is vented by the movement of piston 83 against spring 84. This feature allows complete seating of valve member on seat member 23 within the range if axial movement of valve member 84 because the corresponding high degree of back pressure may be needed in a given tuning situation, i.e., near-complete seating may be required. Thus it does not comprise operating flexibility because of safety, but rather provides both. The conical nature of the valve parts 80, 23 affords smooth application of back pressure and contributes to the fine tuning thereof possible with the invention, because the flow stream is disturbed symmetrically and smoothly.

What has been described is a mixer 10, which is capable of very fine, reproducible, micrometer adjustment of internal parts to afford maximum mixing intensity, yet which can have its working parts removed for cleaning and the like without taking down the whole assembly, or even disconnecting from the line. These and the other features disclosed hereinabove afford a significant advance in this art.

The invention has been described with reference to an illustrative embodiment thereof. Of course, variations therein are contemplated. Those skilled in the art will recognize many equivalent arrangements of parts followmg the principles of the invention set forth and illustrated above and claimed below.

What is claimed is:

1. A tunable acoustic fluid mixer comprising:

(a) a housing providing a fluid passageway from an inlet to an outlet end thereof, and including a first pan of opposed lateral slots at a first axial position, and a second pair of opposed lateral slots at a second axial position, along said housing;

(b) a jet-forming orifice structure within said housing situated upstream of said first pair of slots;

(c) a blade assembly carried within said housing with the blade edge thereof facing said jet-forming orifice;

(d) a first elongated axially slidable member carried on the outside of said housing, normally covering said first pair of slots and including removable means connecting said blade assembly thereto through said slots for axial movement therewith;

(e) a first micrometer movement removably engaged with said first slidable member for precise and repeatable setting of the axial position of said first slidable member and thereby said blade assembly;

(f) a valve assembly carried within said housing downstream of said blade assembly, including a fixed portion and a movable portion;

(g) a second elongated axially slidable member carried 0n the outside of said housing, normally covering said second pair of slots, and including removable means connecting said valve assembly movable portion thereto through said slots for axial movement therewith; and

(h) a second micrometer movement removably engaged with said second slidable member for precise and repeatable setting of the axial position of said second slidable member and thereby of said valve assembly movable portion.

2. A tunable acoustic fluid mixer comprising:

(a) a housing providing a fluid passageway from an inlet to an outlet end thereof and including a pair of opposed lateral slots at an axial position along said housing;

(b) a jet-forming orifice structure within said housing upstream of said pair of slots;

(0) a blade assembly carried within said housing with the blade edge thereof facing said jet-forming orifice;

(d) a valve assembly carried within said housing downstream of said blade assembly, including a fixed portion and a movable portion;

(e) an elongated axially slidable member carried on the outside of said housing, normally covering said pair of slots, and including removable means connecting said valve assembly movable portion thereto through said slots for axial movement therewith; and

(f) a micrometer movement removably engaged with said slidable member for precise and repeatable setting of the axial position of said slidable member and thereby of said valve assembly movable portion.

3. A tunable acoustic fluid mixer comprising:

(a) a housing providing a fluid passageway from an inlet to an outlet end thereof, and including a pair of opposed lateral slots at an axial position along said housing;

(b) a jet-forming orifice structure within said housing upstream of said part of slots;

(d) an elongated axially slidable member carried on the outside of said housing, normally covering said pair of slots, and including removable means connecting said blade assembly thereto through said slots for axial movement therewith; and

(e) a micrometer movement removably engaged with said slidable member for precise and repeatable setting of the axial position of said slidable member and thereby of said blade assembly.

4. A mixer according to claim 3, wherein is further included, an adjustable valve assembly carried within said housing downstream of said blade assembly.

5. A mixer according to claim 2 wherein said valve assembly fixed portion comprises a valve seat, and said movable portion comprises a valve member.

6. A mixer according to claim 2 wherein said valve assembly fixed portion comprises a valve seat, said movable portion comprises a valve member located downstream of said valve seat, and said valve member is spring loaded in the upstream direction so that limited relief movement is afforded in the downstream direction under fluid pressure overloads upstream thereof.

7. A mixer according to claim 1 wherein a third pair of opposed slots are provided adjacent said jet-forming orifice structure, and a third slidable member is carried on the outside of said housing overlying said third pair of slots, to allow access to said orifice structure for removal thereof.

8. A mixer according to claim 1 wherein said valve assembly fixed portion comprises a valve seat, said movable portion comprises a valve member located downstream of said valve seat, and said valve member is spring loaded in the upstream direction so that limited relief movement is afforded in the downstream direction under fluid pressure overloads upstream thereof.

9. A mixer according to claim 1 wherein each of said micrometer movements comprises a thimble having a threaded portion engaged with a threaded portion of the respective slidable member associated therewith, so that rotation of said thimble moves said associated slidable member axially.

10. A mixer according to claim 9 wherein each said thimble includes a disengageable retaining ring which limits the axial movement of the associated slidable member, so that when said ring is disengaged the slidable member can be retracted axially away from the associated thimble suflicient to expose the associated pair of slots in said underlying housing.

11. A mixer according to claim 9 wherein the thimble of each micrometer movement, and the associated slidable member, each bears indicia allowing precise resetting of any relationship therebetween.

12. A mixer according to claim 1 wherein each micrometer movement is lockable at any setting, so that any setting can be maintained during operation.

13. A mixer according to claim 2 wherein said valve assembly fixed portion comprises a conical valve seat, wherein said movable portion comprises a conical valve member located downstream of said valve seat and Wherein said valve member is spring loaded in the upstream direction so that limited relief movement is afforded in the downstream direction under fluid pressure overloads upstream thereof.

References Cited UNITED STATES PATENTS 3,169,013 2/1965 Jones 259-4 3,176,964 4/1965 Cottel et a1 2591 3,278,165 10/1966 Gaffney 259-1 ROBERT W. JENKINS, Primary Examiner.

J. M. BELL, Assistant Examiner.