US3281125A

US3281125A - Vibrator mechanism

Info

Publication number: US3281125A
Application number: US500012A
Authority: US
Inventors: Theodore W Shoe; Mark J Wise
Original assignee: Flexicore Co Inc
Current assignee: Flexicore Co Inc
Priority date: 1965-10-21
Filing date: 1965-10-21
Publication date: 1966-10-25
Anticipated expiration: 1983-10-25

Description

Oct. 25, 1966 w, E ET AL 3,281,125

VIBRATOR MECHANISM Filed Oct. 21, 1965 United States Patent M 3,281,125 VIBRATOR MECHANISM Theodore W. Shoe, Troy, and Mark .1. Wise, Dayton, Ohio, assignors to The Flexicore Co., Inc., Dayton, Ohio, a corporation of New York Filed Oct. 21, 1965, Ser. No. 500,012 4 Claims. (Cl. 259-72) This invention relates to a vibrator mechanism and particularly to a mechanism which is normally disposed beneath a form in which concrete products are being cast. The vibrator mechanism is particularly useful for casting forms of the type in which long concrete slabs are cast.

Vibrators in connection with concrete casting means are wide-1y used. Such vibrators perform a number of functions among which are distributing and compacting a concrete mix throughout a casting form, expelling air bubbles and the like. Vibrators used for such purposes function to convert substantial power into vibrations ranging from about 1,000 cycles per minute up to as much as 8,000 cycles per minute and, in some cases, even more. As a rule, the amplitude of vibration is of the order of about of an inch.

The power level at which such devices generally operate, together with the amplitude, results in creation of such high stresses in the vibrator mechanism as to reduce substantially the normal operating life of such vibrators or important components thereof. A further and serious problem is created by the transmission of vibratory energy from the vibrator mechanism to supporting and foundation structures and adjacent structures. Such undesired vibration not only represents a waste of vibratory energy, since such energy is only desired for the casting form and its contents, but also induces and creates undesired stresses and strains in such adjacent and supporting struc tures and thus tends to reduce the life of such structures.

Because of the above characteristics of such vibrator mechanism, it has been necessary to weld or integrate metal (or steel) parts which are normally made or manufactured separately. In general, it is desirable to use steel in the form of cold, rolled strip or bars as against cast iron or cast steel. develops cracks in the metal. The use of cold rolled steel thus entails welding various parts together. It is important in connection with such welds that the welds are strong and withstand the vibration present in such mechanisms.

In addition to the above, vibrators of this general character frequency include as parts thereof heavy springs. To accommodate the latter, the vibrator mechanism requires metal clamps and other metal parts for anchoring such springs. Such various metal parts must be welded. A conventional vibrator mechanism thus involves a relatively large number of welds and provides a fertile field for fractures to develop.

An additional disadvantage of such conventional mechanisms resides in the fact that the head room for the mechanism between the floor or other support and the bottom of the casing from or load is quite substantial. The greater the head room required, the more difiicult becomes the problem of insuring that the various component parts of the mechanism are not overstressed.

The present invention makes possible a vibrator mechanism wherein the number of separate parts required is reduced to a minimum and wherein the necessity for welds is reduced even further than would normally be warranted by the reduction in the number of parts. In addition to the above, the invention makes possible a vibrator mechanism wherein efiective and efiicient vibra- The latter material generally 3,281,125 Patented Oct. 25 1966 tory isolation is provided to prevent undesired transmission of vibratory energy to foundations and adjacent structures. A further advantage of the new structure embodied in the present invention resides in the compact and comparatively short overall structure which is rendered possible and thus permits of a comparatively low support plane for the vibrator load.

The invention involves a heavy steel vibrator plate which is supported at a number of places on heavy rubber or other resilient elastic material which functions not only to support the vibrator plate but also to shield or isolate the support plate from the basic vibrator frame upon which the entire vibrator frame is carried. Directly supported below such vibrator plate is a shaft carrying unbalanced weights which creates the desired vibratory energy. The last named shaft is connected through a pulley and belt to an electric motor or other source of power.

By virtue of the structure generally set forth above, very short paths for transmitting vibratory energy to the vibrator plate are provided. As many vibration absorbing support means as desired for the vibrator plate can be provided to effectively suppress the leakage of vibratory energy away from the vibrator plate and downwardly to the general vibrator support structure. The vibrator plate itself is adapted to carry the load to be vibrated.

An additional substantial advantage of the new structure resides in the ready accessibility of bearings for supporting the shaft. This feature is highly desirable since bearings in such vibrator mechanism must frequently be renewed.

For a more complete description of the invention reference is now made to the drawing wherein:

FIG. 1 is a perspective view of one of the vibrators employing the present invention, this view illustrating in dotted line a part of a casting form disposed thereon.

FIG. 2 is a plan view of the vibrator mechanism of FIG. 1 wherein the vibrator plate is broken away to illustrate the vibrator mechanism structure.

FIG. 3 is a section on line 33 of FIG. 2.

FIG. 4 is a section on line 4r-4 of FIG. 2.

FIG. 5 is an enlarged sectional detail on line 5-5 of FIG. 2.

The new vibrator mechanism has base supporting plate 10 of any desired shape and size. Base plate 10 is of steel and should be suificiently thick for the required purpose. As an example, forms for casting concrete slabs having a width of the order of 2 or 3 feet and a length ranging up to as much as 50 or 60 feet and having a depth or thickness of the order of about 10 or 12 inches are very heavy so that base plate 10 in such a case may be as much as A" or 1 in thickness. The remaining dimensions of such a base plate would be about 3 feet by about 2 feet or 2 /2 feet. These dimensions are exemplary and the invention is not limited thereto. As a rule, vibrators are disposed at about 10 foot intervals along a casting form.

Rigidly secured to the top of base plate 10 are

end plates

12 and 13 extending parallel to

ends

14 and 15 of base plate 10 and set inwardly therefrom a short distance. Supported on base plate 10 and rigidly secured thereto are additional plates 16 and 17. Additional plates 16 and 17 extend outwardly from the outer face of said plate 12 and cooperate therewith to provide a firm support structure.

End plate 13 is similarly provided with

additional plates

18 and 19. Rigidly secured to the top edges of side plate 12 and additional plates 16 and 17 is one connecting plate 23. A second connecting plate 24 is provided for the top edges of

plates

13, 18 and 19. It is understood that these various plates are of steel and of suitable thickness.

The thickness of the various plates may be of the order of about /2" or These plates are preferably welded together to form a rigid strong support structure. For a vibrator mechanism to be used with a casting form having the dimensions as described above, the height of the framework thus formed may be of the order of about one foot. This support frame is bolted to a floor by bolts passing through apertures at the four corners of base plate 10. The support structure so far described is reinforced by support plate 28 extending between

side plates

12 and 13 rigidly secured thereto as by welding. Support plate 28 is disposed substantially midway between

side plates

12 and 13 and has a substantial portion of the plate between the edges undercut at 29 to clear the vibration generating means.

Top plates

23 and 24 are each provided with apertures at each end thereof. The location of these apertures is illustrated in FIG. 2 together with the support structure. The construction for supporting the remainder of the mechanism is similar insofar as the corners are concerned and accordingly the structure illustrated in FIG. will be described in detail as representative. Thus, support plate 24 is apertured at 30 adjacent an end thereof for accommodating reduced end 31 of pin 32. Reduced end 31 of pin 32 provides an annular shoulder 33 which rests upon the top surface of cross-plate 24. Resting on top of cross-plate 24 and surrounding a part of enlarged portion 32 of the pin is thick washer 34.

Washer 34 has a diameter which is about equal to the width of cross-plate 24- and fits snugly about the enlarged portion of pin 32. Washer 34 is rigidly secured by welding to cross-plate 24. The thickness of washer 34 may, as an example, be of the order of about /2 or even somewhat greater. Inasmuch as no great precision is required in the manufacture of the vibrator mechanism, the diameter given here is on the generous side. Pin 32 extends upwardly above the top of washer 34 and functions as a guide to hold in position heavy rubber washer 36. The diameter of washer 36 is somewhat greater than the diameter of washer 34 and the thickness of rubber washer 36 is substantially greater than washer 34. As an example, the rubber washer 36 may have a thickness of the order of about 1 /2" to about 2" and, in any event, the thickness of washer 36 is sulfliciently great so that the top of pin 32 will be substantially below the level of top surface 38 of the rubber washer.

.The difference in elevation between the top surface of rubber member 36 and the top of pin 32 should be well beyond the amplitude of vibration to be generated and may, for example, be about A in the specific structure described as an example of the embodiment of the invention. Rubber washer 36 is of solid rubber of the type used for mounting presses and may have a hardness of between about 55 and about 60 on the durometer scale. Such rubber is used widely in absorbing the shock of punch presses and similar mechanisms and this grade of rubber is generally known in the trade as press rubber.

Resting on top of rubber member 36 and forming an inverted cup shaped shield is member 40 having depending skirt portion 41 surrounding the outer face of rubber member 36 and extending downwardly below the bottom face of rubber member 36. Skirt portion 41 is sufiiciently larger in diameter so that it clears the outer face if washer 34. The space below skirt 41 should be clear for a sufiicient distance to accommodate easily the amplitude of vibration to be encountered. Member 40 has pin portion 43 extending above the body thereof and this pin portion is adapted to lie within aperture 45 of one corner of vibration plate 50. Vibration plate 50 has apertures adjacent the four corners thereof which are adapted to register with the support assembly illustrated and described in connection with FIG. 5.

Pin portion 43 has a diameter which is substantially greater than that of shouldered pin portion 32 and fits loosely in apertures 45.

Vibration plate 50 is of steel and has substantial thickness of the order of about 1" for the particular size mechanism that has been set forth. Vibration plate 50 has

steel strips

51 and 52 rigidly secured there to as by welding.

Strips

51 and 52 are disposed along opposite sides of plate 50 and preferably along the long dimension of the plate. The ends of each of

strips

51 and 52 have blocks 54 to 57 inclusive rigidly anchored thereto. The distance between the blocks on strip 51 is substantially the width of a casting form shown in dotted line in FIG. 1. The same is true of the distance between block 56 and 57 along strip 52. Thus, the bottom of a castings form will rest upon

strips

51 and 52 and be firmly wedged between the blocks at the ends of these strips.

Means for creating vibration in plate 50 are suspended from this plate below the lower face. Thus, bolted to and suspended from plate 50 substantially midway between

end plates

12 and 13 is shaft 60 journalled in

bearings

61 and 62. Shaft 60 has an end portion projecting beyond bearing 62 carrying pulley 64. Pulley 64 is belt driven from an independently mounted motor not shown. Shaft 60 has rigidly secured thereto

eccentric Weights

66 and 67. As illustrated in FIG. 3,

weights

66 and 67 are oriented so that the eccentric portions thereof are aligned insofar as rotary position is concerned.

What is claimed is:

1. A vibrator mechanism for use on forms for casting concrete slabs, said mechanism comprising a rigid steel base plate, a plurality of upstanding steel supports rigidly secured to said base plate and forming a rigid support structure, said support structure having at the top thereof a plurality of apertured steel plate portions, a vertical steel pin for each aperture, each pin having a guide portion extending above the top of said support structure, a heavy washer of non-metallic elastic vibration absorbing material disposed about the guide portion of each pin and resting on top of the support structure, an inverted cup shaped steel member disposed over the top of said heavy washer, said inverted cup shaped member having an upwardly extending pin portion, a steel vibrator plate disposed over the support structure, said vibrator plate having apertures each of which registers with the upwardly extending last named pin portion, means on the top face of said vibrator plate for retaining a casting form against lateral movement in normal vibrating position and means supported from the bottom of said vibrator plate for creating vibrations in said plate, said heavy washers serving to substantially suppress the transmission of vibratory energy to the support structure.

2. The construction according to claim 1 wherein said vibration creating means includes a shaft journalled in bearings below said vibrator plate and eccentric Weights carried by said shaft.

3. A vibrator mechanism comprising steel support means including steel plate members extending horizontally in the normal operating position of the mechanism, said plate means having apertures, a steel pin for each aperture, said pin having a shoulder resting on top of said apertured plate and having an upwardly extending pin portion, a Washer of press rubber disposed about the top portion of said pin, said rubber washer having a substantial thickness, a steel inverted cup-shaped member disposed about said rubber washer and resting on top thereof, said inverted cup-shaped member and the free top end of said pin being separated by a distance which is substantially larger than any amplitude of vibration, said inverted cup-shaped member having an upwardly extending pin portion substantially larger in diameter than said shouldered pin, a vibration plate having a plurality of ap rtures, each aperture adapted to register with the 3,281,125 5 6 upwardly extending pin portion of each inverted cup References Cited by the Examiner member, means for supporting the vibratory load on said UNITED STATES PATENTS vibration plate, and means including a shaft and eccentric weights supported from the bottom of said vibration plate 2555688 6/1951 Flam 259 72 for creating vibration, said rubber washer functioning to 5 2,990,720 7/1961 Scholtes 259 72 suppress vibratory energy from going downwardly of said 2,996288 8/1961 Kavaflau et a1 259-72 rubber Washen 3,146,997 9/1964 McKinney 259-72 4. The construction according to claim 3 wherein said vibration plate has a plurality of support strips and sup- WALTER SCHEEL Primary Exammer' port blocks for accommodating the load to be vibrated. 10 R. W. JENKINS, Assistant Examiner.