US2274225A

US2274225A - Apparatus for handling concrete

Info

Publication number: US2274225A
Application number: US305317A
Authority: US
Inventors: Cecil J White
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-11-20
Filing date: 1939-11-20
Publication date: 1942-02-24
Anticipated expiration: 1959-02-24

Description

Feb. 24, 1942. c; J. wHlT l APPARATUS FOR HANDLING CONCRETE Filed Nov. 20, 1959 Patented Feb. 24, 1942 NED STATESk a PmTENi-lf OFFICE, y

APPARATUS FOR HANDLING' (30N CRETE cedri. White, Minneapolis, Minn. Application kNovember-20, 1939, Serial-No. 305,317

40mm. (01.94-46) I hopper isv the bucket of a paving mixer, this invention comprises a method and apparatus. for preventing the segregation of the larger particles of the concrete mixture during the deposit of the mixture upon a supporting medium from a hopper or the like.

My inventiony also comprises a method and apparatus for preventing the larger particles of the aggregate of a paving mixture from lodging against the side forms or transverse joints in a slab or other structure. The lodgment of such large particles of. the aggregate prevents the l proper deposit and entrance of suicient mortar at suchi locations-to ll all the voids existing between the larger particles, and my invention guides the larger particles into the interior of themassfof material and permits the finer par-A ticles to. lodge againstV the side forms or transverse joints.

My invention also comprises a method and apparatus for retaining a material, such as a sheet of .joint material used in roadways and` other structures,Y in properfdesired position during, the depositv of the concrete, and simulta neously preventing the larger particles of the concrete or other mixture from lodging against the form material, blocking oiT the depositl and entrance of sufficienti mortar at such location to` .ll all'voids between the `large particles but guidingthe large particles into the intermediate body of` themixture, permitting the liner particles of the mixture to lodge against the joint material.

My invention. also comprises a construction of the holder for. such joint. material in a manner thatv will hold'. the joint material in proper posi-y tion during thel deposit of the concrete but also -permitting the holding device to be easily rev moved after the concrete has been deposited. My apparatus may also be used against the side forms utilized in concreter roadway construction, for thepractice of my method, in preventinglthe formation of voids and lstony'pockets at the' sides f androrners of the slabs or other structures.

Ordinarily when concrete is disohargedfrom the4 lower restricted throat of al hopper or concrete mixer bucket, there is a tendency for some of theV larger aggregate to become segregated from the mixture and to roll dow-n andlodge` at the toeo,f the:v depositedmixture. Especially when the hopper is propelled longitudinally over the subgrade and at a predetermined elevation above the subgrade. The hopper is so manipulated that it tends to distrbutefthebatch ofA concrete'rather v'uniformly over the subgrade in an elongated,

attened pile, thereby reducing the labor of distributing the mixture between the side forms. I have found that when concrete is so deposited, the larger particles of the aggregate tend to separate from the mixture and to roll down the sides of the pile or mass and to accumulate at the toes or edge'sof the pile in rows or ribs of segregated masses. After the deposit of the rst material is completed in this manner, it is supplemented by manual distribution of the material laterally, with the result that richer portions of the concrete" are placed upon these segregated portions of the larger aggregate. The pavement slab is then completed, 4leaving these rows 01 ribs1 of segregated` material in the lower strata of the concreteslab, and the voids in this segregated material are then not completely lled with thef mortar.V This results in a pavement slab which has largeI void or honeycombed volumes of considerable length and width which weaken the slab structurally and likewise permit the ingress of: water which may later freeze, disintegrating the slab.

I have found that by the use of my invention, the segregation of the larger aggregate from thev mixture-is prevented, `since the larger aggregate isretained within:` the body of the mixture during thel deposit thereof uponl the subgrade so that upon completion, the slab is of a uniform mixture throughout, free from voids and honeycombs and of'uniform strength and density. y

In the construction of concrete roadway slabs upon a prepared subgrade, the lateral' edges of the slab are shaped by what are commonlycalled longitudinal side formsanchored tothe subgrade` and dening the direction and height of the edges of the slab. At selected intervals in the length of the slab, there are placed contraction yand expansion joints, the latter in many cases consistingof avertical sheet or strip of a compressible; and expansible `mastic material extending'from the subgrade upward almost" tothe up-` per iinishedsurface of the slab; These joints are. disposedtransversely to the axis of the roadway and extend from one side forni across the slaby to the opposite side form. I have found that when concrete isdeposited in the slab: in the` usualv manner upon thegsubgrade between the forms and against. the transverse joints, the llarger particles of the aggregate tend to become segregated from the mixture and to become deposited against the side forms and against the transverse joints, especially in the corners and at the lower edges of the slab. Although the concrete is later brought to desired finished surface elevation against the side forms and against the transverse joint, the mortar does not flow readily into the voids of these segregated volumes, with the result that honeycombs and stony pockets, having a deficiency of mortar, exist at these critical 1ocations when the slab has been completed.

The apparatus employing my invention is shown in the accompanying drawing, in which:

Figure 1 is a perspective view of a bar carrying downwardly inclined ngers, which bar is adapted to be mounted on the inside of the hopper in such a way that the ngers guide the larger pieces of aggregate toward the interior of the mixture being discharged from the hopper;

Figure 2 is a, vertical sectional View illustrating the hopper equipped with the ngers shown in Figure 1 and held above a supporting medium upon which the concrete is deposited;

Figure 3 is a vertical sectional View taken on the line 3 3 of Figure 2;

Figure 4 is a Vertical elevational view of another form of my apparatus;

Figure 5 is a top plan view of a portion of the apparatus of Figure 4;

Figure 6 is a Vertical cross sectional View taken on the line 6-6 of Figure 4, and

Figure 7 is a perspective view of another form of my apparatus.

In the drawing, Figure 1 shows a bar indicated by the numeral I supporting a plurality of downwardly .inclined lingers 2. In Figures 2 and 3 I have shown a bucket or hopper 3 such, for example, as the bucket of paving mixers. Bars I are bolted or otherwise secured to the inner faces of the walls 4 of the bucket 3 just above the lower edges of the walls surrounding the discharge orice of the bucket. The fingers 2 extend inwardly and downwardly at the orice. The fingers are so spaced that they permit the portion of the mixture consisting of the ner particles thereof to pass between theml for discharge upon the subgrade 5. The original concrete mixture is indicated at 6 of Figure 2 and the larger particles at I. The spacing of the fingers 2 is such as to prevent the larger particles 'I from passing between the fingers 2. Consequently, during the ow of the material 6 downwardly from the bucket 3, the larger particles 'I are guided toward the interior of the mass so that when the concrete 6 is deposited upon the subgrade 5 these larger particles 'I are retained within the body of the mass 6 and are not separated therefrom at the toe 8 of the deposited mixture. In Figure 3 I show the bucket 3 being propelled horizontally in the direction'of the arrow 9.

In Figures 4, 5 and 6, I show the bar II) having the downwardly inclined ngers 2, the bar I performing essentially the same function as bar I of Figure 1. In Figures 4, and 6, the bar IU is shown consisting of two parts II which together form an inverted U, having downwardly projecting legs to which are attached the fingers v2. At either end of the parts II, I attach the sustaining members and handles I2. The parts I I may be provided with the hinges I3 by means of which the downwardly extending legs of the parts II may be opened or closed. I also provide the clamp I4 operating to hold together the parts II and I2 and spacer sleeve Ma between the parts I2, the clamp I4 being arranged for removal from the members I2 so that the parts II may be opened or closed with respect to each other. I may elect to use only one-half of the bar IB, consisting of one part II with its attached ngers 2. The handles I2 are provided with the grooves or notches I5 to engage the side forms I6. I also provide the joint material I'I alongside of which, as a stiffener, I provide the vertical plate I8. I likewise provide the clamping channel I9 to hold the material I'I and the plate I8 in `desired juxtaposition. It will be seen that the bar I0, consisting of the parts II (especially as shown in Figure 6), sustain and hold the clamping channel I9 and thereby sustain the joint material I'I in the desired position. The ngers 2 may extend downwardly to make contact with the subgrade 5 to assist in bracing the joint material I'I against lateral deflection and distortion.

In Figure 6, I show the concrete 6 containing the large particles 1 and the finer materials 20. I also indicate the space 2| between the fingers 2 and the joint material I'I, into which spaces 2| the ner materials 20 have been permitted to pass while the larger particles 'I have been restrained by the lingers 2 to a position within the body of the materials 6. In the manipulation of the apparatus shown in Figures 4, 5 and 6, the joint material I'I with its plate I8 and clamping channel I9 is placed in position upon the subgrade 5 extending between the side forms I6 and the parts Il, I8 and I9 are held in rigid position by means of the downwardly extending parts II of bar I0, which is sustained and xed upon the side forms I6 by means of the notch I5. Concrete 6 is then deposited upon the subgrade 5 in the manner hereinbefore described, and when the surface 22 of the concrete 6 has been properly obtained, the clamp I4 is removed and then by means of the handles I2 the bar IIJ with its attached parts are extracted from the concrete 6, after which normal finishing and tooling operations are continued.

In Figure 7, I show a different form of my apparatus arranged to be used in conjunction with the side form I6. I provide the bar 23 having an inverted U-shaped cross section which is placed upon the upper rail 24 of the form I6, the bar 23 having the downwardly projecting legs 25 attached to which-are the downwardly inclined lingers 2. This bar 23 with its ngers 2 would serve the same function with respect to the side forms I5 that bar I0 with its fingers 2 performs with respect to the joint material I'I of Figures 4, 5 and 6.

While I have used a paving mixer bucket for the purpose of illustrating the manner in which my invention may be used, as shown in Figures 1, 2 and 3, it will be understood that the invention may be employed in a great variety of other commercial equipment. Likewise, while in Figures 4, 5, 6 and 7 I have utilized the forms and joints normally utilized in the construction of concrete roadway slabs, it will be understood that my invention may be used in a great variety of other forms of construction. My invention may also be employed in conjunction with spouts,l chutes or elephant trunks, for the deposit of cone crete or other mixtures into forms or other positions where the conc-rete is to be utilized.

Having thus described my invention, I nowV claim and desire to secure by Letters Patent of the United States:

1. In apparatus for treating material, such, for instance, as jconcrete which contains particles of varying sizes, for the purpose of preventing movement of the larger particles to the outside of the mass and segregation of such larger particles from the mass during deposit of the material, a container -for holding the material and for dropping it upon a lower place of deposit, a series of suitably supported members projected from the outside into the outer part of the downwardly moving mass, saidmembers being inclined downwardly from the outer limits of the container toward the inner part thereof and being spaced apart to guide the larger particles downwardly and inwardly and to permit passage between them of the remainder of the moving mass and being of such lengthfas to Apermit the free passage of the larger particles over their inner ends.

2. In apparatus for treating material such, for instance, as concrete which contains particles of varying sizes, for the purpose of preventing movement of the larger particles to the outside of the mass Iand segregation thereof from the mass during deposit of the material, a container having walls and having a discharge orice at its lower part and a series of guide members suitably mounted and projecting into the path of the material discharged from the orice, said members being inclined downwardly from the outer part of said orifices toward the inner part thereof and being successively spaced apart to guide the larger particles downwardly and inwardly in said path and to permit passage between them of the remainder of the moving mass, and being of such length as to permit the free passage of the larger particles over their inner ends.

3. In a device of the class described, a supporting means designed to be placed adjacent the path of a mass of material containing particles of various sizes and moving by gravity from one place to another, a series of opposed lingers suitably mounted on a support and inclined inwardly and downwardly, a hopper having a low orifice and supported above said ngers, whereby materials deposited from said oriiice pass said lingers, said lingers spaced apart to prevent passage of the larger particles between the successive fingers and to guide such particles toward and over the lower ends of said iingers, and to permit the passage of sm-aller particles between the successive fingers. f

4. In a device of the class described, a supporting means designed to be placed adjacent the path of a mass of material containing particles of various s-izes and moving by gravity from one place to another, aframe having opposed sides, a series of fingers mounted on said sides and incline'd inwardly and downwardly, a hopper having a low orifice supported above said frame, whereby materials deposited from said orifice pass said fingers, said ngers spaced apart to prevent passage of the larger particles between the successive iingers and to guide such particles toward and over the lower ends of said fingers, and to permit the passage of smaller particles between the successive ngers.

' CECIL J. WHITE.