US2960316A - Fluid driven vibrator - Google Patents

Description

Nov. 15, 1960 J. D. M KELLAR ,960,

FLUID DRIVEN VIBRATOR Filed April 25, 1958 4 Sheets-Sheet 1 Nov. 15, 1960 J. D. MOKELLAR 2,960,316

FLUID DRIVEN vIBRAToR Filed April 25, 1958 4 Sheets-Sheet 2 Jilin I E W mummiii i 50 4 I so N V- 1 1950 J. D. MOKELLAR 2,960,316

FLUID DRIVEN VIBRATOR Filed April 25, 1958 4 Sheets-Sheet 3 waw Nov. 15, 1960 J. D. M KELLAR 2,950,316

ID DRIVEN VIBRATOR Filed April 25, 1958 4 Sheets-Sheet 4 WWW? |llllll lllllfll 72 T I In, a

FLUID DRIVEN VIBRATOR John D. McKellar, Inglewood, Calif. (1767 Chetamon Court, Sunnyvale, Calif.)

Filed Apr. 25, 1958, Ser. No. 730,860

7 Claims. (Cl. 2591) The present invention relates to mechanical vibrators, and more particularly, to a vibrator of the type utilizing one or more rotating eccentric weights to produce a shaking force. This application is a continuation-in-part of my prior copending application Serial No. 533,271, filed September 9, 1955, now U.S. Patent No. 2,840,354, issued June 24, 1958.

Vibrators or shakers are used in many industrial and constructional operations for various purposes, such as on test fixtures for determining the ability of components to withstand vibration, to agitate feed hoppers or various types of cutting blades, to mix, settle, tamp, or level thick fluid compositions, and to vibrate numerous other structures. The present invention is especially well suited for shaking concrete forms, such as when pouring concrete pipe sections, for example.

Most presently known and used devices of this nature consist of an eccentric weight, or two geared eccentric weights, driven by an entirely separate electric or air motor connected thereto. The mounting shafts or other mounting means are journalled in a housing which is adapted to be rigidly attached to the concrete form or whatever device is to be vibrated. These assemblies are thus rather complicated and expensive, having relatively many actual operating elements. Other known vibrators are inefficient regarding operating power, expensive to maintain because of relatively fragile parts and easily damaged bearings and the like.

It is a general object of this invention to provide a fluid driven vibrator for the above described purposes which is extremely simple, rugged, and inexpensive especially from an operational standpoint.

Another object of the present invention is to provide such a vibrator having substantially fewer moving or operating parts than are necessary in conventional vibrators, thus making for economical and relatively silent operation.

A further object is to provide a vibrator assembly wherein the parts themselves can be made with a minimum of close fitting or critical-tolerance dimensions.

Still another object of the present invention is to provide a vibrator having the above desirable features with a maximum efiiciency of operation superior to the best presently known and more complicated vibrator units.

Other objects and features of advantage will be apparent upon reading the detailed description of a preferred embodiment of this invention to follow.

Briefly, my invention comprises a basic, rotatable vibrator wheel structure having an integral eccentric weight and integral turbine blades for being rotatably driven by air, for example. The blades are preferably curved in one direction or plane, only, and are essentially straight in the length dimension thereof, which is the thickness or width dimension of the wheel. The wheel has these various integral elements, including central hub means, provided thereon in such a manner and in such locations (as will be described later) that an extremely eflicient turbine is the result, and so that the States Patent "ice vibrator wheel comprises a single castable component. The wheels are adaptable to being used singly, paired, or stacked in tandem as desired, preferably in a protective housing which is easily mounted on and dismounted from the assembly to be vibrated. The housing preferably comprises one main fixed assembly, including mounting provisions for attachment to the job to be vibrated, and a removable lid or cover bolted to the main assembly after the turbine wheel is in place, with the cover containing one end support for the wheel axis. A nozzle in the housing permits air under pressure to blast onto the turbine blades for rotating power, which air is then exhausted to the atmosphere through novel protected exhausted means. In one embodiment of wheel, a hollow center is provided inwardly of the blades, the ends or sides of the wheel benig closed, thus establishing an exhaust air flow path out past the same blades again for additional rotative force.

In the accompanying drawings:

Figure l is a perspective external view of the vibrator assembly of my invention, as viewed from above.

Figure 2 is a perspective view of the assembly in Figure l, as viewed from beneath.

Figure 3 is a bottom view of the top cover of the vibrator assembly shown in Figures 1 and 2.

Figure 4 is a longitudinal section of the nozzle, taken as indicated by the line 44 in Figure 1, showing also a portion of the interior wheel.

Figure 5 is a perspective view of the turbine wheel of the assembly in Figures 1 and 2, showing the lower side thereof.

Figure 6 is a plan view of the wheel in Figure 5.

Figure 7 is a perspective view of another wheel structure usable in the present vibrator.

Figure 8 is an exploded perspective view of an alternate embodiment of housing and turbine wheel.

Figure 9 is an edge view of the wheel shown in Figure 8.

Figure 10 is a plan view of the same wheel, partly cut away and showing a horizontal cross section taken as indicated by the line 10-10 in Figure 9.

Figure 11 is a vertical cross section of the same wheel, showing its entire height, viewed as indicated by the line 1111 in Figure 10.

Referring first to Figures 1 and 2 for a description of one embodiment of my invention, there is shown a housing 10 comprising a lower Welded assembly 11 and an upper cover plate 12. Lower welded assembly 11 consists of a large cylindrical mounting pipe 14 open at its lower end and secured at its upper end to a lower cover plate 15 as by inside welding 16, and a larger diameter short cylindrical barrel 17 attached solidly to the lower plate 15 as by outside welding 19. Lower plate 15 is provided with a central opening in which is pressed a bushing 20, and four exhaust holes 21 within the area of the mounting pipe 14. Four corner bolt holes 22 are also drilled in lower plate 15 beyond the barrel extent. Barrel 17 has a nozzle pipe 24 welded at an angle to its outer circumference.

Upper cover plate 12, further shown in Figure 3, has four corner bolt holes 22a and a central bushing 20a matching the corresponding elements of the lower plate 15. A circular groove 25 is further provided in the lower surface of upper cover plate 12 to fit over the top edge of the barrel 17. When assembled, the vibrator contains a turbine wheel 26 (Figures 5 and 6) enclosed within the barrel 17, and a mounting pin 27 rotatably supports the turbine wheel 26, while corner bolts 29 and nuts 30 hold the upper cover plate 12 securely in place. Cotter pins 31 and 31a, for example, through the ends of the mounting pin 27 hold the latter in place, and a small cotter pin retainer 32 is preferably fixed on the upper cover plate 12 to prevent the mounting pin 27 from rotating, even though it is press-fitted into the bushings 20 and 20a.

As shown in Figure 4, a nozzle opening 35 in the barrel 17 provides the entrance for the jet of driving air or other fluid. Nozzle pipe 24, welded concentrically with opening 35, contains a pressed-in nozzle 36. A welded collar 37 around the outer end of nozzle 36 limits the inward travel of nozzle 36 when assembling, and determines its operating position. In this way, various sizes of nozzles may be interchanged as required. A threaded end 39 on nozzle pipe 24 accommodates an air fitting (not shown) for connection of an air line to the vibrator.

The eccentric weight turbine wheel 26 of Figures and 6 contains a sealed ball bearing 40 pressed into a center opening from each side and positioned by a snap ring 41 on each side, the bearing inner race being a press fit on the mounting pin 27. When assembled, the various dimensions are preferably such that the bearing inner races will rest against an inner flanged end surface 20b of each of the bushings 20 and 20a during operation, while the upper cover plate 12 is tightened down with the barrel 17 fitting tightly against the bottom of groove 25. Thus, the bearings can be under an endwise compression load. This does not harm them in any way, but is rather an advantage since it makes certain that the wheel 26 is always properly and firmly centered. The bushing inside flanges 26b prevent them from being pressed outwardly through the cover plates. The groove 25 will prevent dirt from entering the barrel interior, but another important purpose of the groove is to maintain exact concentricity of the bushings 20 and 20a by preventing slippage of the upper cover plate 12 under the severe vibration forces set up by the eccentric weighted turbine wheel 26 during high speed operation.

The main structure of the turbine wheel 26 will now be pointed out. It is a one-piece casting having a substantially plane top surface 44. The lower side, shown facing upwardly in Figures 5 and 6, has a plurality of turbine blades 45 cast integrally with the wheel in an annular ring portion around the rim thereof and extending to the outer edge of the top surface 44. The inner or interior portion of the wheel 26 comprises a thick body 46 with a cored arcuate channel 47 around one side thereof. Thick body 46 and the wall of channel 47 form a thickened portion of the wheel 26 connecting the bases of all the blades 45 together. This channel 47 does not extend completely through the wheel, but a Web 49 remains, this web being of approximately the same thickness as the top surface 44, or thin portion of the wheel. It is thus seen that the wheel is thereby given an eccentricity, in order to produce a vibrating force when rotated.

The turbine blades 45 are straight sided in the vertical dimension, except for the usual amount of draft angle for casting purposes, but are curved in the radial direction to form an approximately semicircular blade contour on the concave sides 50. The blades 45 are thickened on the rear side at the base end where they are integral, of course, with the body 46.

It will be noted that the blades 45 also extend deeper in the width direction of the wheel 26 than does the body 46. This is to provide sufiicient air exhaust space to the center of the wheel, since the bottom edges 51 of the blades 45 operate very close to the lower plate 15 of the housing 10. From the center of the bottom of the wheel 26, the air passes through the four exhaust holes 21 in the lower plate 15 and out to the atmosphere through the large mounting pipe 14.

Besides operating closely to the upper and lower plates 12 and 15, the outer rim of the wheel 26 is spaced by only a small clearance from the interior of the barrel 17, as shown in Figure 4. The wheel top surface 44 performs the double purpose of strengthening the integral blades 45 and also confining air at the top side to absorb more air velocity and thus increase the efliciency'. It

thus directs the air downwardly, as the top is completely closed and there is no air flow in this direction. The eccentricity may be modified, if necessary, by machining down the body 46 between the blades and a central hub portion 54.

The vibrator of Figure 1 is installed or attached to the component to be vibrated by means of a circular clamp (not shown) having two semi-circular halves bolted to one another, to receive the mounting pipe 14. In this manner, the lower plate 15 can rest on the clamp parts while being attached. A further distinct advantage of the invention as just described is the protection afforded from foreign matter which might fall or drop on the assembly while in operation, or from dust or other particles in the air while the unit is not operating, or dirt which might enter the working chamber if the unit itself is dropped. It will be obvious that the entire top is closed, assuming an air line connected to the nozzle pipe 24, and that the exhaust holes 21 are nearly fully protected and shielded by being enclosed and recessed at the upper end of the rather long mounting pipe 14.

Figure 7 shows an alternate type of design for the eccentric turbine wheel. Here, a wheel 26a is also producible by a simple single casting process, except for having circumferential teeth 56 which may be machined after casting. Turbine blades 45a are formed integrally with the wheel and are located just inwardly of the root diameter of teeth 56.

The teeth 56 are provided for vibrators which require a pair or more of eccentrically weighted wheels to produce a straight-line shaking force when geared together. In the latter instance, the housing would naturally be larger in the lateral direction, and may be built as described and claimed in my prior copending application Serial No. 533,271, which was referred to hereinbefore.

This wheel 26a is shown with a central bore 57 for receiving a bearing or shaft, and has through-apertures 59 separated by spoke-like elements 60 extending for substantially degrees around the bore 57. The opposite continuous portion 61 therefore forms an eccentric weight to provide the desired vibrating result. Wheel 26a may be preferred over the previously described wheel for lighter duty applications. As stated in the aboveidentified application, several identical wheels can be combined in various manners to act in various ways and have an overall eccentricity which is easily variable.

Figure 8 shows a vibrator housing and wheel of the same kind as heretofore disclosed, but having several improved features. A barrel 17a is welded to a lower plate 15a which is in turn secured in a similar manner to a mounting angle 62. Attachment holes 63 in the angle 62 furnish means for using various installation devices which are simpler than the aforementioned circular clamps. Exhaust holes 21a are provided in the barrel 17a, while the lower plate 15a within barrel 17a is imperforate. Corner bolt holes 22b are located in the corners of lower plate 15a. At the center, lower plate 15a has a recessed cup 64 therein, provided with an end plate 65. Nozzle pipe 24a enters the barrel 17a at an angle and is similar in construction to that shown in Figure 4.

Wheel 26b in Figure 8 represents a one-piece casting and incorporates several novel structural features differing from the ones previously described. Details of this wheel 26b will now be described, reference being bad to Figures 8, 9, 10, and 11. All elements of this wheel 26b are integral, as illustrated, but for purposes of description the several elements Will be mentioned and referenced individually. Thus, a spindle 69 projects from each side of the wheel 2612 at the center thereof, and the wheel is solid throughout this central section 70, as shown in Figure 11. A circular top side '71 and a circular bottom side 72 of thickness T extend from the spindle 69 to the periphery or outer rim.

As shown in Figure 10 specifically, a plurality of turbine blades 45b surround the wheel between the top and bottom sides 71 and 72, the other edges of the blades 45b being flush with the circumference of these sides. Blades 45b are formed with concave air-facing front surfaces 74 which are essentially semicircular in cross section with the imaginary diameters there-of aligned substantially on radii of the wheel. Rear surfaces 75 of blades 45b are nearly V-shaped in cross section, with a relatively thick apex.

An eccentrically located mass 76 fills the entire width of the wheel 26b at a predetermined position from the central section 70 to an outer edge 77 which is spaced inwardly from the inner edges of the blades 45b. The circumferential extent and planiform shape of this mass 76 is chosen to provide the desired eccentricity of the wheel, considering the speed and vibratory force which a particular application requires. The remainder of the wheel 26b thus comprises a hollow interior 79, and it will be further noted that the top and bottom sides 71 and 72 are imperforate.

The method of casting the wheel 26b is conventional in the art and includes using a sand core which provides all the voids making up the hollow interior 79. The core is in a pulverized condition after casting, and is easily removed through the openings between the blades 45b.

One spindle bearing 80 is shown in Figure 9. When the wheel 26b is assembled inside the barrel 1712 as indicated in Figure 8, this bearing 80 mates with the wall of the cup 64. Another end bearing (not shown) rotatably mounts the other end of spindle 69 in a cup of a removable upper cover plate (not shown) which is similar to the corresponding upper plate 12 in Figure l.

The manner of operation of the latter assembly in Figure 8 is as follows. Air under pressure entering through the nozzle in nozzle pipe 24a impinges against the blade front surfaces 74 to produce a first driving force on the wheel 26b, the air then entering the hollow interior 79. Since the wheel 26b fits closely adjacent the upper and lower plates (15a for example), and since the top and bottom sides 71 and 72 have no openings therein, the air present in the hollow interior 79 builds up to a measurable pressure greater than atmospheric. It then escapes radially between the blades 45b at positions other than at the nozzle location. Due to the blade shape as described herein, the escaping air thus produces a second driving force upon the wheel 26b in the same direction as the first of course. The reason for leaving a space between the blades 45b and the outer edge 77 of the mass 76 is now evident.

Finally, the air exists through the exhaust holes 21a to the atmosphere. It will be noted that the exhaust holes 21a are efiectively protected against entrance of damaging foreign matter by being located behind the attachment bolts which will be installed through the corner bolt holes 22b.

The structure of Figure 8, having the bearings in the cover plates, is preferable to that in Figures 1 through 6, where the bearings are in the Wheel, since improved support and higher speeds are obtainable. Also, the turbine construction itself is more efiicient. The end plates 65 of the cups 64 (one on each side) enclose and protect the sealed ball bearings 80.

Since the weight location cannot be seen from the outside of the wheel 26b as described above, some indicating means, such as two relatively small holes for example, can be cast in one of the sides 71 or 72 at locations which will index the invisible Weight. Such holes do not interfere with the air flow path explained before, since there is not sufficient passage space between the wheel sides and the enclosing covers to permit more than a negligible amount of exhaust air therethrough. If no index means is provided on the wheel 26b as cast, the weight position can be determined if required by rotatably mounting the wheel in a vertical plane and marking the position where it comes to rest.

Vibrators containing the wheel 26 shown in Figures 5 and 6 normally operate at 8,000 rpm. and produce a vibrating force of 2,660 pounds. At this performance, only 60 cubic feet of air per minute are required at a pressure of" psi, and the useful bearing life is more than 330 hours. If rotated slower, say at 3,300 r.p.m., a 450 pound force is produced, bearing life increases to over 4,000 hours, and the air requirements are naturally less. The wheel 26b in the assembly of Figure 8 is rated at 12,000 rpm.

It is thus seen that a simple, efficient, and rugged shaker is provided, which requires only the attachment of a hose or line carrying pressurized air to operate it. Of course, it also operates on gas or steam, and the same design is suitable to be hydraulically driven. The inexpensive parts can be quickly and easily made and assembled, and there are no adjustments necessary on the single-wheel vibrator. The entire assembly comprises only eight parts, including an adaptor clamp plate and excluding bolts and nuts. The present invention has only two wearing parts, the sealed ball bearings. Its maintenance cost is therefore extremely low, differing radically from other presently made air-driven external shakers having many more parts and periodically requiring expensive service kits.

While the invention has been described and shown herein in certain specific detail, it is to be distinctly understood that the invention is not limited to the specific embodments disclosed, since many modifications may be made without departing from the principles involved, and the invention is therefore claimed in any of its equivalent forms within the scope of the appended claims.

What is claimed is:

1. In a vibrator, a single-piece turbine wheel comprising means for rotatably mounting said wheel at a central axis thereof, one side surface of said wheel being substantially fiat, a plurality of curved turbine blades aligned normal to the width of said wheel and located just inwardly of the periphery of said one surface, said one surface being relatively thin at an outer annular ring portion occupied by said blades, with said thin portion joining the adjacent side edge of all said blades, and a fixed eccentrically located thickened portion of said wheel between the center thereof and said blades, said thickened portion extending outwardly to join the inner base ends of said blades and continuing completely around said wheel at said ends of all said blades as a reenforcement thereto, but being substantially narrower than the width of said blades to permit air flow past said blades to the center portion of said wheel.

2. In a vibrator, a single-piece turbine wheel comprising means for rotatably mounting said wheel at a central axis thereof, said wheel having two relatively thin opposite outside surfaces which are substantially flat and imperforate from the outer rim to said mounting means, said surfaces being spaced by a plurality of curved turbine blades aligned normal to the width of said wheel and located just inwardly of the periphery of said surfaces, the interior portion of said wheel between said blades and said mounting means having an eccentrically fixed weight therein and being otherwise hollow, and means defining passage for air flow from said blades inwardly to the center portion of said wheel past said weight.

3. In a vibrator, a wheel comprising central means for rotatably mounting said wheel, two spaced fiat, circular, and substantially imperforate side portions extending outwardly from said mounting means to the rim of said wheel, a plurality of curved turbine blades flush at their outer edges with said rim and joining said side portions at the respective ends of said blades, and an eccentrically positioned fixed mass filling a predetermined space between said side portions, the outer extreme of said mass being separated from the inner edges of said blades to define air passage between all said blades and the hollow interior portion of said wheel.

4. A fluid-driven vibrator comprising a housing hav ing a cylindrical barrel and two covers secured at the ends of said barrel, said covers containing central coaxial Wheel mounting means, an eccentrically Weighted turbine wheel within said barrel, said wheel being rotatably mounted in said mounting means, said Wheel having fixed curved turbine .bldaes with concave sides positioned perpendicularly to the width of said wheel around the circumference thereof, a nozzle extending at an angle through said barrel and directed at the concave sides of said blades, means defining exhaust openings in only one of said covers and being in communication with the inner sides of said blades, and a relatively large open-ended pipe fixed at one end to said one cover with said exhaust openings within said pipe, whereby said pipe provides both external mounting means for said vibrator and protection for said exhaust openings.

5. A vibrator comprising an eccentrically weighted turbine wheel having two imperforate side portions spaced at the rim by a plurality of fixed curved turbine blades with concave sides thereon, said wheel having a hollow interior inwardly of said blades, said turbine wheel eccentrically weighted by a mass fixed to said side portions within a portion of said hollow interior, said mass having an outer edge spaced inwardly from the inner edges of said blades to permit air fiow between all said blades to saFd wheel interior around said mass, a housing surrounding said wheel and rotatably mounting the latter, a

8 nozzle extending through said housing at an angle and directed at the concave sides of said blades, and exhaust openings through said housing spaced around the periphery thereof in the same plane with said nozzle.

6. Apparatus in accordance with claim 5 wherein said wheel is rotatably mounted on an integral spindle in bearings placed in said housing, said housing being closed around the exterior of said bearings.

7. Apparatus in accordance with claim 5 wherein said 0 Jnousing includes a main fixed assembly and a removable cover providing access for replacement of said wheel, and cover attachment bolt means positioned to overlie said exhaust openings, whereby the latter are substantially protected from entrance of foreign matter to said wheel.v

References Cited in the file of this patent UNITED STATES PATENTS V 1905 780,971 Boekel Ian. 31,

794,606 Goldsborough July 11, 1905 1,294,050 Chute Feb. 11, 1919 1,346,221 Liedtke July 13, 1920 1,352,588 Egedi Sept. 14, 1920 1,584,944 Johnson May 18, 1926 1,675,560 Jubien July 3, 1928 1,858,043 Glass May 10, 1932 2,000,930 Nagy May 14, 1935 2,142,237 Canady Ian. 3, 1939 2,172,195 Elson Sept. 5, 1939 2,436,251 Dobie et a1. Feb. 17, 1948 2,807,509 Anderson Sept. 24, 1957 2,840,354 McKellar June 24, 1958 UNl'lED STATES PATENT oTTTcE QEMWTQATWN 0F QQRRECTTQN Patent No. 2,960 8l6 November 15 1960 John D, McKellar It is h'ereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below. 1

Column 2 lines 13 and 14,, for "exhausted" read exhaust line 16 for "benig'l' read being column 5, llne 2 for "other" read outer line 51 for "exists read exits column 7 line 11 for bldaes read my blades Signed and sealed this 23rd day of May 19618 (SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Attesting @fiicer Commissioner of Patents

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