US 2187224 A
Description (OCR text may contain errors)
s. l l. .A
Jan. 16, 1940. M M com 2,187,224
PLASTERING SYSTEM Original Filed Dec. 28, 1956 v o I I for. I
( Y Y' nf P n arculsujo/y.
, 4 Patented Jan.` 16,1940
UNITED STATESv PATENT OFFICE Application 8 Claims.
This invention relates generally to methods of and means for forming plaster or cement walls and ceilings, and relates especiallyto a plastering system disclosed in my prior copending application, entitledl Plastering system, Ser. No.
101,953, led September 22, 1936.
In accordance with the method for forming plaster or cement walls andceilings as disclosed in my said prior application, there is provided l0 a comparatively large smooth plane backing-up surface, which is placed in the plane of the wall to be constructed. The plaster is placed from a position to the rear of the wall being formed, either by hand or `with use of mechanical means such as a cement gun, against the surface of this form. The plaster or cement,` as the case may be,
is placed through any mesh or other wall reenforcing means that may be used. When a section of the wall hasvbeen built up to the requisite thickness by lso placing the material through the screen or other reenforcing means against the surface of the form, the form is moved `to a new position, or else a second form isplaced next to the first, and a second section of the wall is built up in the same manner.` The' operator thus works from the rearward side ofthe Wall, building up the wall to the desired thickness by `placingthe material through the reenforcing `screen against the movable form, and as he progresses along `3bthe wall, the same form is either moved to be kept abreast with this operation, or several forms may be used, the operator progressing from ferm to form, and the forms being removed from the Wall sections which have been completed and 35" placed again at positions ahead of the operator. l It is usually preferable to placeor stretch a flexible sheet, eitherof paper or cloth, as burlap, in the plane of the wall to be formed, this sheet lying over the surface of the backing-up form. This flexible sheet may be` allowed to remain on the plaster or cement until partially or thoroughly set, after which it is removed. l
Undercertain conditions, a plane of weakness develops in a wall formed by this wall forming method. Especially when the material is applied through use of an air pressure mechanical means such as a cement gun through a mesh, steelframe..
or other reenforcing, the plasteror cementitious material is deflected by the mesh or reenforcing I and subjected to the action of eddies, producing a plane of weakness just `outside the mesh `or other obstruction or reenforcing means. Usually the extent of this condition is suchtthatthe plane of weakness extends out'to the nished surface, 55 causing the material outside ofthe reenforcing December 2s, 193s, serial No. 117,788
Renewed June 10, 1939 means to be very weak and porous. The extent of this condition is usually such that the outline of wire reenforcing, studs and other bracing members of the frame can be easily traced on the finished surface when the wall has been ccmpleted. y
,'It is accordingly the primary object of the present invention to provide a method and means for solidifying plaster or cementitious material applied from the rearward side of a wall to be formed through a reenforcing means such as a mesh or around studs against a backing-up form placed in the plane of the finished surface of the wall. f
l In accordance with the present invention, the movable backing-up `form against which the plaster or cement is projected through the reenforcing meshlis subjected to mechanical vibration, which densies or solidifies the plaster or cement, removing the effect of eddies and work- 20 ing the material together to remove entirely the pattern of the reenforcing means through which the material was placed.
The invention will be more fully understood by referring now to the following detailed description, reference for this purpose being had to theaccompanying drawing, in which:
Fig. 1 shows a portion of an exterior wall of a building to be plastered in accordance with the present invention;
Fig. 2 is a cross-section taken on line 2-2 of y Fig. 1;
V`Fig. 3 is a View taken as of Fig. 1;
Fig. .4 is a detail of a vibrator motor; and Fig. 5 is a detail of a motor supporting bracket. In the drawing numeral I0 designates generally an unfinished building being formed with a plaster or cement Wall in accordance with the present invention. Foundation walls are indicated at II, vlower and upper iioor joists are indicated at I4 and I5, respectively, concrete floor slabs at I6, flooring at I'I, and ceiling at I8. Wall studding (of wood or steel) is indicated at I9, and ,hog wire (mesh) reenforcing for the plaster or cement is indicated at Ztl, being indicated as stretched over studding I9. The illustrated steel studding and hogrwire constitute a reenforcing frame for the wall, being typical of any suitable openwork reenforcing framework or reenforcing means for the placed material.
The vertical plane of the' outer surface of the wall to be constructedis indicated in Fig. 2 at W, and stretched in this plane W is a flexible sheet `22, of paper or cloth such as burlap. As here indicated by line 3--3 shown, this sheet 22 is secured to one corner of the building, as at 23, and it will be understood that the sheet is supported at its other end so as to be stretched in Wall plane W. In some instances this flexible sheet is omitted, though it is usually found useful.
A large backing-up form 30, in the present instance of substantially the vertical dimension of a story of the building, is positioned with its smooth inner vertical surface 3| in wall plane W, so as to back up a corresponding section of flexible sheet 22.
'Ihough this backing-up form may be mechanically constructed in various Ways, I here show a preferred construction in which it is made up of a series of horizontally extending sections 32 placed edge to edge and connected at the back by frame members 34 and 35.
Insofar as the present invention is concerned, any suitable means for supporting the trowel or form in wall plane W may be employed. For illustrative purposes, I show the form supported by false work 45, here indicated as temporarily secured to a bracket 40 fastened to the foundation wall, and provided with a channel 4l adapted to receive and position the lower portions of the frame members 34 and 35 of the form so that the form is supported with its inner surface 3| in plane W. As shown in Fig. 2, the form is of suicient height to overlap and engage a portion of the outer surface of the previously laid second story half of the wall, and this engagement may be relied on to hold the form against tilting inwardly. The form is indicated as held up to plane W by means of, a bracket 44 supported by false work 45. Any suitable means may of course be employed for the purpose of temporarily supporting the trowel in the position illustrated, and it will be understood that, if desired, false work 45 may be attached to the form at both top and bottom to prevent it from tilting either inwardly or outwardly.
The plastering operation is carried on as follows: One or more backing-up forms are rst placed in position, edge to edge, at one end of the surface to be plastered, for instance at the left-hand end of the Wall surface shown in Fig. 1. Thus, in Fig. 1 three forms 3D, 30a and 30b'are shown placed edge to edge. The plaster, or cement, as the case may be, is` then placed against rst form 3|] from the rear, and this is preferably, though not necessarily, done with a plaster or cement gun 50, of any known or appropriate type, in the hands of the plasterer (see Fig. 2). As is well understood, dry cement and sand mixture is supplied to the nozzle of such a cement gun, water being sprayed into the stream at' the nozzle. This water may not sufficiently wet the material during its travel from the nozzle to the wall (usually a distance of approximately two feet) and there the cement and water is mixed by the action of the air and following material of the stream. In fact, one reason for the porosity of the material beyond the screen or any obstruction in the no-rmal process is that a part of the water is caught and held by the wire and part of the material that goes beyond is pulled in behind the obstruction and thus separated from the water. To remedy this condition, I preferably wet the burlap sheet that covers the backing-up form, and the water provided by this burlap is mixed with the material by contact and the vibratory action and is conducive to a better distribution of the water,
as well as aiding in consolidating and densifyingv and water in proper proportions are thus shot in this manner from the gun through the reenforcing mesh or mat 20 against surface 3l of first form 3B, or against the liexible sheet covering lsaid form, and is built up to the wall thickness desired. The plaster thus shot against the form is indicated at P in Fig. 2.
To consolidated completely the plaster or cementitious material outside the plane of reenforcing screen 20, backing-up form 30 is mechanically vibrated. As a typical means for accomplishing mechanical vibration of the form, I indicate electric Vibrator motors 52 secured to the outer sides of forms 3E! and 30a against which the wall material has been, or is being, applied. The shaft 53 of each of said motors is provided With an eccentric weight 54. As a typical and convenient means for temporarily securing the velectric motors to the form, I show each motor as provided with a supporting hook 55 engageable with brackets 56 secured to the rear of the forms. As here shown, each form is provided with two vertically spaced brackets, on which may be hung two vibrator motors, although it will be understood that this number may be varied as may be found appropriate, and that in many instances one motor on each form will be suicient.
Motors 52 being in operation, the plaster or cementitious material projected against the backing-up forms through mesh 2E] is vibrated and consolidated, the eifect of eddies is eliminated and the pattern of the reenforcing means is obliterated, the material between the reenforcing mat or mesh and surface plane W being thoroughly worked together and densified to eliminate all such conditions of weakness. It was mentioned previously that a proportion of the water caught by the wire screen or reenforcing as the material is placed is separated from the wall material. To aid in remedying this condition, I preferably wet the burlap sheet that covers the backing-up form before the wall material is placed. The water provided by this burlap is mixed with the material by contact and the vibratory action and is conducive to a beter or more uniform wetting of and distribution of water through the wall material. E l l When the plasterer has finished building up the wall surface against first form 35, he moves over to second form 35a, building up the wall in the same manner over the area covered by the second form, and when this is finished he moves on to the third form 30h and works as before. A suitable time after the operator has passed beyond rst form 30, said form is removed and placed aheadof third form 35o, and in this manner the wall is progressively formed across the side of the building. When the wall surface is finished, the exible sheet is peeled oi.
The described electric vibrators are placed in turn on the backing-up forms to consolidate the material as it is placed, or even after it has been placed but before the form is removed and placed in a new position ahead. Preferably, the vibrators are placed and operated on each form during placement of the plaster or cement on that form, either throughout the entire time that particular correspnding wall section is being built up, or only during a portion or portions of that period, though it is possible to consolidate the material by vibration after the plastering operator has progressed to the next section if `enough moisture is present.
l The general plastering `method to which the present invention relates when practiced together with the speciiic improvements herein disclosed permits solid plaster and cement walls to be formed in a fraction of the time ordinarily required.
l. The method of forming a Wall of plaster or cementitious material about an openwork reenforcing frame, that `comprises placing a comparatively large plane surfaced backing-up form in the plane of the outer surface of the wall to be constructed, projecting the wall materials and Water from the rearward sideof the Wall to be constructed 'through said openwork reenforcing frame and against said form, and vibrating said form to mix, `consolidate and densify the material which has been deflected in passing the reenforcing frame.
2. The lmethod of forming a Wallof plaster or cementitious material about an openwork reenforcing` frame, that comprises placing a comparatively large plane surfaced backing-up form inthe plane of the outer surface of the wall to be constructed, projecting the wall material and Water from the rearward side of the Wall to be constructed through said openwork reenforcing frame and against said form, and vibrating said form while the material is being placed to mix,`
consolidate and densify the material `which has been deflected in passing the reenforcing frame.
3. The method of forming a Wall of plaster or cementitious material about an openwork reenforcing frame, that comprises placing a comparatively large plane `surfaced. backing-up form in the plane of the outer surface of the Wall to be constructed, stretching a flexible sheet along said plane in contact with said form, wetting said sheet, placing the Wall material and water from the rearward side of the wall to be constructed through said reenforcing frame and against said sheet backed up by said form, and vibrating `said form to mix and consolidate the materials so placed against said flexible sheet.
4. The method of forming a Wall of plaster or cementitious material about an openwork reen- `forcing frame, that comprises placing a comparatively large plane surfaced backing-up form in the plane of the outer surface of the wall to be backed up by said form, and vibrating said form to mix and consolidate the material so placed against said flexible sheet. l y
5. The method of forming a wall of plaster or cementitious material about an cpenwork reenforcing frame, that comprises placing a comparatively large plane surfaced backing-up formy in the plane of the outer surface of the Wall to be constructed, stretching a iiexible sheet along said` plane in contact with said form, projecting the Wall material and water from the rearward side of the Wall to be constructed through said open- Work reenforcing frame and against said sheet backed up by said form, and vibrating said form while said material is being placed to mix, consolidate and densify the material which has been divided in passing throughthe reenforcing frame.
6. Means for forming a Wall of plaster or cementitious material about a previously erected openwork reenforcing member, comprising a comparatively large plane surfaced backing-up form placed in the plane of the -outer surface of the Wall to be constructed, means for projecting plaster or cementitious material from a position at the rear of the Wall to be constructed past and about said openwork reenforcing member against said form, and means for Vibrating said form so as to mix, consolidate and density the material `which hasbeen divided in passing through the `reenforcing frame in travelling from the projecting means toward said form.
'7. Means for forming a wall of plaster or cementitious material about a previously erected openwork renforcing member, comprising a comparatively large plane surfaced backing-up form placed in the plane of the outer surface of the Wall to be constructed, a flexible sheet stretched in the plane of the outer surface ofthe Wall to be constructed and lying in contact With said form,v means for projecting plaster or Vcementitious material from a position at the rear of the wall to be constructed past and about said open- Work'reenforcing member against said flexible sheet backed up by said form, and means` for vibrating said form so as tol mix, consolidate and densify the material which has been divided in passing through the reenforcing frame in travelling from the projecting means toward said form.
8. The method of forming a structure of plaster or cementitious'material about a reenforcing meanathat comprises placing a backing-up form in the plane of one surface of the structure to be` formed, forcibly discharging the material past said reenforcing means and against said form from a position to the rear of said surface, and vibrating said form to mix and consolidate the `material so placed against said form.
MARCUS M. CORY.