US3061278A

US3061278A - Vibrator tool

Info

Publication number: US3061278A
Application number: US815576A
Authority: US
Inventors: Dreyer Herbert
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-05-25
Filing date: 1959-05-25
Publication date: 1962-10-30
Anticipated expiration: 1979-10-30

Description

Oct. 30, 1962 H. DREYER 3,061,278

VIBRATOR TOOL Filed May 25, 1959 ESC 2 Sheets-Sheet 1 INVENTOR.

H. DREYER VIBRATOR TOOL Oct. 30, 1962 2 Sheets-Sheet 2 Filed May 25, 1959 IZZ/ j 171298597 QEyE-,

JNVENTOR.

frire/velg.

United States Patent Ofice 3,061,278 Patented Oct. 30, 1962 3,061,273 VIBRATOR TGL Herbert Dreyer, 2137 Paseo Del Mar, Palos Verdes Estates, Calif. Filed May 25, 1959, Ser. No. 815,576 8 Claims. (Cl. 2591) This invention relates to improved vibrator type devices for use in vibrating or agitating a mass of material, such as a body of wet cement which is to be compacted to an increased density condition by the vibration in order to increase the strength which the cement has after hardening. For packing cement solidly within a for-m, there have in the past been devised various types of vibrator devices, which are. lowered into the wet cement and act to vibrate the cement in a manner causing it to Settle down to a compacted condition. These Vibrators normally include a weight contained within a closed housing, and mounted to rotate rapidly but eccentrically Within the housing, to give the housing a rapid vibrational movement in the cement. Though such vibration of the cement has proven very effective for packing it tightly in a form, devices of this type have had certain opera.- tional disadvantages, as a result of which they have required very frequent repairs in use, particularly because of the bearing difficulties resulting from the rotation of the heavy eccentrically mounted weight within the housing of the device.

The general object of the present invention is to provide an improved vibrator type device which is capable of serving this cement packing function, as well as other vibrator functions if desired, and which is structurally much simpler than the above discussed' conventional type of Vibrator. Particularly contemplated is a device of this type which is adapted for reliable operation over very long periods of time without the necessity for the usual frequent repair and replacement of parts. A device embodying the invention desirably includes two body parts which are submersible as a unit within a body of cement or other material, and one of which parts is free forI rapid essentially vibrational movement relative to the other to agitate the material. Such relative movement of the two body sections is produced in a very unique manner by provision of a rotating unit, which is power driven to turn about a predetermined axis relative to one of the body sections, and which has a portion journalled for rotation relative to the other body section about a second and slightly different axis. In one form of the invention the two axes are disposed at a slight 4angle to one another, while in another form the two axes are parallel but slightly offset from one another. Preferably, the rotating Vunit takes the form of a shaft structure having one of its ends journalled in a first of the body sections for rotation about a first of the axes, and having its other end journalled within the second body section for rotation relative thereto about the second axis. This relationship causes the second body section to oscillate slightly with respect to the first body section as the rotating unit turns, and as a result of the slight angularity or offset of the two axes.

The entire device is desirably hermetically sealed, so that it can be completely immersed within the cement or other Work material without any of that material having access to the interior of the device. In order to provide for such sealing between the two body sections, there may be positioned between these two sections, and desirably bonded toboth of the sections, an annular fiexible seal ring or element disposed about the shaft or rotating unit. This flexible part may be lformed of rubber or other elastomeric material, and is capable of flexing freely in accordance -with the relative displacement of the two body sections, while at the same time continuously maintaining a fluid tight seal between these body parts. For optimum operating results, it is desirable that one of the body sections contain an electric motor, acting to drive the rotating unit relative to that section. The sealing of the body structure then of course is such as to very effectively seal the motor against contact of any of its moving parts with the work material.

The above and other features and objects of the present invention will be better understood from the following detailed description of the typical embodiment illustrated in the accompanying drawing in which:

FIG. l is a lfragmentary vertical Section through a cement form, showing a vibrator type tool constructed in accordance with the invention and positioned within the cement in theform;

FIG. 2 is an enlarged vertical section through the FIG. l tool;

FIGS. 3 and 4 are fragmentary vertical sections showing two variational forms of the invention;

FIG. 5 is a view similar to FIG. 2 showing another variational form;

FIG. 6 is an enlarged fragmentary section taken on line 6-6 of FIG'. 5; and

FIG. 7 is a section through stillanother form of the invention.

Referring first to FIGS. l and 2, i and particularly FIG. 1, I have represented at 10 a cement or concrete form, which may typically be consideredto be the lform for a wall of a reinforced concrete building. The form 10 is normally made up of a series of boards 11 suitably secured together to give the ultimate wall any desired configuration. The cement or concrete 12 is poured into the form 10 in wet uncured condition, to assume the shape of the form 10.

The vibrator device of the present invention is shown at 13 in the figures, and is adapted to be immersed completely within the body of wet cement 12, to vibrate that cement in a manner causing it to pack or settle downwardly very compactly within form 10. Vibrator 13 is suspended within the cement 'by means of a flexible sealed and insulated electrically conductive line 14 through which energizing current is vfed downwardly to unit 13. Suspending line 14 may be connected at its upper end to a control switch 15 which is held in the hand of an operator, and by which the operator opens and closes the electrical circuit to unit 13. Current may be fed to switch 1S through a line 16 having a conventional plug 17 at its end. The power utilized by the apparatus is preferably volt, either A.C. or D.C., the motor" within the unit 13 typically being (operable on either A.C. or D.C.).

Vibrator unit l13 includes an upper hollow body section ,18 and a relatively movable lower hollow-body section 19. Upper section 18 contains an electric motor 20, whose shaft 21 projects downwardly into the lower body section 19 to actuate it. The electrically conductive suspending line 14 is connected into the upper end of upper body section 18, and may include two parallel flexible insulated wires 22 contained within a flexible fluid tight hose or outer sheath 23, typically formed of rubber or the like. The outer hose 23 may have an enlargement 24 -at its lower end, which is securely anchored within a counter-bore Z6 in part 18 by means of a threaded retaining ring 25. This ring 25 is tightened to -a condition in which it forms an effective annular fluid tight seal between part ,18 and enlargement 24 of the hose, to prevent the entry of any cement into the interior of hose 23 or body part 18 at the point of interconnection of these parts.

Both of the body parts '18 and 19 are formed of a rigid material, typically a suitable steel or other metal. These two parts may be both internally and externally a universal type motor cylindrical, and of a common diameter so that the lower section forms essentially a continuation of the upper section. As previously mentioned, motor is desirably a universal type motor, operable on 110 volt A.C. or D.C. power. This motor is represented in the figures as having an outer tubular metal housing 122, to the inner surface of which there is mounted a conventional stator structure 123 within which rotor 1-2'4 is rotatably contained. At its opposite ends, motor housing 122 carries two ball bearing assemblies 125 and 126, which rotatably journal the shaft 21 and carried rotor structure 124 of the motor for rotation about a vertical axis 27. As will be understood, shaft 21 extends entirely through the rotor structure, and carries a commutator 28 coacting with spring pressed brushes 29 for conducting energizing current to the rotor windings. Housing 122 of the motor is externally cylindrical, and of a size corresponding to the internal diameter of upper body section 18 at 30, so that the entire motor may be slipped upwardly into body section 13 during assembly of the apparatus. The motor is retained in this position within body section 13 by means of a lower ring 311, which is threadedly connected into section 18 at 32, and which is annularly sealed with respect thereto by an elastomeric or other seal ring represented at 33.

:In order to produce a vibrational movement of lower body section 19 relative to upper body section 18 in response to rotation of the motor shaft 21 and rotor 124, the shaft 21 is bent at a location 34, so that the lower portion of the shaft extends at a slight angle with respect to the upper portion. More particularly, the upper portion of shaft 21 above point 34 is centered and turns about the previously mentioned main vertical axis 27 of the motor. The lower portion of shaft 21, beneath point 34, is centered and turns about a second axis 35, which is disposed at an angle a to main axis 27, and which intersects that main axis at the point 34. This lower portion of the shaft is rotatably journalled within body section 19 for relative rotation about axis 35 by means of two axially spaced

ball bearing assemblies

36 and 37, which are close fits within the inner cylindrical bore 3S of body section 19, and are spaced apart axially by a spacer tube 39 interposed between the outer races of bearings B6 and 37. The

bearings

36 and 37 and spacer 39 are retained in xed positions within body part 19 by means of a retaining ring 40, screwed into part 19 at 41, and sealed with respect thereto by an annular elastomeric seal ring 43. This ring 40 tightens the lowermost bearing 37 downwardly against a transverse shoulder 44, with the lower end of body part 19 being closed beneath bearing 37 by an externally rounded nose portion of part `19. To facilitate assembly of the apparatus, and particularly to enable application of the various ball bearings to shaft 21, this shaft may decrease in diameter at the locations 46 and 47 just beneath

bearings

126 and 36 respectively, as shown. Also, the inner r-aces of the various ball bearings l125, 126, 36, and 37 may all be relatively tight pressed ts on the associated portions of shaft 21, and the outer races of bearings 125 and 126 may be tight pressed ts within motor housing 122, so that the ball bearings will all function as thrust bearings as well as radial bearings, to maintain each of the body sections l18 and 19 in a fixed -axial position relative to the shaft.

An 4annular uid tight seal is formed between

rings

31 and 40, and about shaft 21, by means of a flexible seal element 48, typically formed of a suitable resiliently deformable elastomeric material, such as rubber. This seal ring 48 is desirably annularly vulcanized or otherwise tightly bonded in fluid tight relation to both `of the

rings

31 and 40, along the upper and

lower surfaces

49 and 50 of ring 48. To enhance the bond at these points, the engaged surfaces of the rigid preferably metal rings 3.1 and 40 may be roughened or irregularized along their entire annular extent, with the rubber of ring 48 then being vulcanized to these roughened surfaces, to form a /lvery tight and strong bond between the rubber and metal. The resilience of ring 48 normally tends to return that ring to a condition in which the cross-section of the ring (as seen for example in the plane of FIG. 2) is of uniform size and shape along the entire annular extent of the ring. This normal cross-section of the ring is of a vertical thickness which is half-way between the two thicknesses shown at opposite sides of FIG. 2. When the apparatus is assembled, the angularity of the lower portion of shaft `21 to its upper portion causes the ring to be deformed to the FIG. 2 condition. As will be understood, the upper surface of ring 40 extends directly transversely of axis 35, and the lower surface of ring 31 extends directly transversely of axis 27.

To now describe the manner of use of the illustrated device 13, assume first that cement 12 has been poured into form 11 of FlG. l, and that plug 1'7 has been connected to a suitable source of volt A.C. or D.C. power. The operator may then iactuate switch 15 to energize motor 20, and then lower tool 13 into the cement or concrete 12 by manipulation of flexible conductive line 14. The energization of motor 20 causes shaft 21 to turn rapidly about axis 27 relative to upper body section 18. Since the lower portion of shaft 21 (beneath bend location 34) is disposed about an `axis 35 extending `at a slight `angle to main axis 27, this lower portion of the shaft swings bodily about :axis 27, :and causes lower body `section 19 to correspondingly swing about axis 27, to produce an essentially vibrational type of movement having an amplitude represented by the angle b in FIG. 2. This vibrational movement of lower body section 19 relative to upper body section 18 causes a rapid vibrational movement of the cement or concrete, to pack the cement or concrete down `very tightly within form 10 so that the ultimate product will be of maximum density and strength. For optimum results, the motor 20 should be a very high speed type of motor, typically turning at a speed of about 10,000 r.p.m. or greater. As the two body sections lmove relative to one another, the elastomeric ring 48 of course ilexes continuously in accordance with the relative movement of the two body parts. As seen in FIG. 2, it is desirable that the point of bend 34 of the Shaft be located directly radially inwardly of, or within, the flexible ring 48.

It is contemplated that the angle a of deviation between the two `

axes

27 and 35 will in most instances be not more than about 5 degrees.

The variational form of the invention shown in FIG. 3 may be considered to be identical with that of FIGS. l and 2 except for the addition of a plurality of circularly spaced rigid bolts 60 for transmitting rotation from upper body section 18a to lower body section 19a (corresponding to

sections

18 and 19 of FIGS. 1 and 2). Each of the bolts is rigid and extends through openings 611 `and 62 in inner `flange portions 162 of

rings

31a and 40a, which openings are sufficiently wider than the bolt in a direction extending radially of

axes

27a and 35a to avoid interference by the bolts with the vibrational movement of part 19a relative to part 18a. Beneath the bolt heads 63 land nuts 64 there rare confined four rubber rings 65, which `are capable of sufficient resilient deformation, as the motor turns, to allow for the relative movement of the body parts. As will be understood, the bolts are tight enough fits within apertures 62 to effectively transmit rotary movement lbetween

parts

18a and 19a, to thereby avoid the imposition of excessive rotary forces on ring 48a.

The form of the invention shown in FIG. 4 is the same 'as that shown in FIG. 2, except for the addition of a counterweight 121b which is rigidly carried by shaft 2lb yat a location just above the point of intersection 34b of the two faxes 27b and 35h. This weight 121b is offset eccentrically with respect to main axis 27b, and in a direction which is exactly the opposite of the direction in which 35b is offset with respect to main axis 27b. That is, if the :axis 35b is offset directly to the left of main axis 27h, as viewed in PIG. 4, thenfthe center of gravity of counterweight projection or lug 121b should be olfset directly to the right of main iaxis 2.7b. The purpose of counterweight 1Z1b is to counter balance the eccentric weight of the lower portion of shaft 2lb (beneath point 34b), as well as the eccentric weight of lower body section 19b and the associated part, to thereby minimize or eliminate Iany tendency -for upper body section 18b to vibrate when the device is -in operation. In order to attain this purpose, the weight 121i), in the optimum arrangement, is sized to substantially exactly counter balance the eccentricity'of the lower portion of the shaft, body section 19b, and other Iassociated eccentrically mounted parts.

FIGS. 5 and 6 show another form of the invention, which may be considered to be the same as that of FIGS. l and 2 except in the following respects. In the rst place, the two axes 27` and 35C of the upper and lower portions of shaft 21C, instead of being disposed Iat an angle to one another, are disposed parallel to one another but a-re `offset slightly as represented at d. The upper portion of shaft 21C, above point 34C, is journalled for powered rotation relative to the upper body section 18C Iabout the upper axis 27C. The lower externally cylindrical portion of shaft 21C` (beneath point 34e) is journalled for rotation within and relative to lower body section 19e about the axis 35e. These two upper and lower portions of shaft 21C are integral with one another and therefore rigidly interconnected for rotation together. Consequently, as the upper motor structure 20c drives the shaft about axis 27e relative to body section 18C, the eccentricity of the lower portion of the shaft Will cause that portion to swing about axis 27e, and thereby cause bodily rotary movement of lower body section 19C, this rotary movement having the effect of a limited range vibrational type of movement, which will compact and settle cement or other material into which the device is lowered. As in the other forms of the invention, the upper and lower body sections are resiliently interconnected by an elastomeric seal ring 48e, which allows only very limited vibratory type movement of lower body section 19C relative to upper body section 18e. It is noted also that, in FIG. 5, the upper body section 18C may be of an external diameter which is suciently greater than the external diameter of lower body section 19C to prevent the periphery of lower body section 19c from ever projecting laterally beyond the periphery of upper body section 18C. That is, if the cylinder dened by the outer surface of upper body section 18e` were continued downwardly, as represented at 118C, -then the outer surface of lower tbody section 19C should in all positions be contained entirely within that extended cylinder 118e. The purpose of this is to avoid any possibility of lower section 19t,` ever projecting to a position in which it might catch ion any reinforcing metal element or other part or shoulder formed in the body of cement, in a manner such that this engagement might interfere with effective upward withdrawal of the device 13e from within the body of cement.

FIG. 7 represents fragmentarily another variational form of the invention, which may be considered to be the same as that of FIGS. 5 and 6, except that a counter balancing weight 121d is formed on and rigid-ly carried by shaft 21d at a location just above the point of juncture 34d of the two upper and lower relatively offset portions of the shaft. This counterweight 121d is offset laterally from main axis 27d of the device in a direction which is just the opposite of the direction in which lower axis 35d is offset, and the counterweight has a mass which is just sulicient to properly counter balance the eccentricity of the lower portion of the shaft, as well as lower body section 19d and the carried bearings and other parts. The counterweight 121d then functions to prevent or minimize vibrational or rotational movement of upper body section 18d when the device is in operation.

I claim:

1. A tool adapted to be lowered into and vibrate a body of material, comprising a lirst and upper hollow body section and a second body section therebeneath and free for limited movement relative thereto, an electric motor in said iirst section having a driven shaft journalled for rotation about a predetermined first essentially vertical axis relative to said irst body section, means forming an extension of said shaft rigidly carried by the shaft for bodily rotation therewith about said lirst axis and projecting downwardly into said second body section but disposed at a slight angle relative to said first axis, means journalling said shaft extension in said second body section for rotation relative thereto about a second axis disposed at said slight angle relative to said first axis so that said bodily rotation of said second portion about the rst axis causes the second axis and thereby said second body section to swing about the iirst axis to thereby vibrate said material, and a flexible connection between said two body sections retaining the second section against rotation with the shaft relative to the rst section.

2. A tool as recited in claim l, in which said flexible connection includes an annular elastomeric member interposed axially between and bonded to and forming a fluid seal between said two body sections at a location about the location at which the shaft extends between said two body sections.

3. A tool as recited in claim 2, including a flexible eleci trically conductive line connected to said iirst body section for suspending the sections in said material, said body sections and said line being hermetically sealed against the entrance of any of said material thereinto when the body sections are completely immersed in said material.

4. A tool as recited in claim 1, including a weight carried by said shaft eccentrically with respect to said iirst axis and at a location to at least partially counterbalance the weight of said shaft extension.

5. A tool adapted to be lowered into and vibrate a body of material, comprising a first and upper hollow body section and a second body section therebeneath and free for limited movement relative thereto, an electric motor in said first section having a driven shaft journalled for rotation relative to said first body section about a predetermined lirst essentially vertical axis, means forming an extension of said shaft rigidly carried by the shaft for bodily rotation therewith about said first axis and projecting downwardly into saidsecond body section and centered about a second axis which is parallel to but offset slightly from said first axis, means journalling said shaft extension in said second body section for rotation relative thereto about said second axis so that said bodily rotation of said extension about the first axis causes the second axis and thereby said second body section to swing about the rst axis to thereby vibrate said material, and a flexible connection between said two body sections retaining the second section against rotation with the shaft relative to the irst section.

6. A tool adapted to be lowered into and vibrate a body of material, comprising a first body section and a second body section free for limited movement relative to the first section, a power driven rotating structure having a first portion rotatably carried by said iirst body section for rotation relative thereto about aA predetermined first axis, said rotating structure having a second portion connected to said rst portion for bodily rotation therewith about said irst axis, and means rotatably mounting said second portion of the rotating structure to said second body section for rotation relative thereto about a predetermined second axis, said second axis being slightly different than said rst axis so that by reason of said difference in the two axes said bodily rotation of said second portion about the first axis causes said second axis and thereby said second body section to swing about the iirst axis to vibrate said material, said rotating structure including a connection attaching said two portions thereof together in a relation maintaining said two axes slightly diierent and retaining said two portions, both when said structure is stationary and when it is turning, against relative shifting movement to positions bringing the two axes into coincidence, said rotating structure being a shaft structure in which -said two portions form essentially two shafts rigidly connected together and journalled in said two body sections respectively for rotation about said two axes respectively.

7. A tool as in claim 6 wherein said second axis is disposed at a slight angle to said rst axis and wherein said connection maintains said axes at said slight angle,

both when said structure is Stationary and when it is turning.

8. A tool as in claim 6 wherein said second axis is parallel to but slightly offset from said rst axis and wherein said connection maintains said axes in said parallel and offset relationship, both when said structure is stationary and when it is turning.

References Cited in the le of this patent UNITED STATES PATENTS